//! This file contains thin wrappers around OS-specific APIs, with these //! specific goals in mind: //! * Convert "errno"-style error codes into Zig errors. //! * When null-terminated byte buffers are required, provide APIs which accept //! slices as well as APIs which accept null-terminated byte buffers. Same goes //! for UTF-16LE encoding. //! * Where operating systems share APIs, e.g. POSIX, these thin wrappers provide //! cross platform abstracting. //! * When there exists a corresponding libc function and linking libc, the libc //! implementation is used. Exceptions are made for known buggy areas of libc. //! On Linux libc can be side-stepped by using `std.os.linux` directly. //! * For Windows, this file represents the API that libc would provide for //! Windows. For thin wrappers around Windows-specific APIs, see `std.os.windows`. //! Note: The Zig standard library does not support POSIX thread cancellation, and //! in general EINTR is handled by trying again. const root = @import("root"); const std = @import("std.zig"); const builtin = @import("builtin"); const assert = std.debug.assert; const math = std.math; const mem = std.mem; const elf = std.elf; const fs = std.fs; const dl = @import("dynamic_library.zig"); const MAX_PATH_BYTES = std.fs.MAX_PATH_BYTES; const is_windows = builtin.os.tag == .windows; const Allocator = std.mem.Allocator; const Preopen = std.fs.wasi.Preopen; const PreopenList = std.fs.wasi.PreopenList; pub const darwin = @import("os/darwin.zig"); pub const dragonfly = std.c; pub const freebsd = std.c; pub const haiku = std.c; pub const netbsd = std.c; pub const openbsd = std.c; pub const solaris = std.c; pub const linux = @import("os/linux.zig"); pub const plan9 = @import("os/plan9.zig"); pub const uefi = @import("os/uefi.zig"); pub const wasi = @import("os/wasi.zig"); pub const windows = @import("os/windows.zig"); pub const posix_spawn = @import("os/posix_spawn.zig"); comptime { assert(@import("std") == std); // std lib tests require --zig-lib-dir } test { _ = darwin; _ = linux; if (builtin.os.tag == .uefi) { _ = uefi; } _ = wasi; _ = windows; _ = posix_spawn; _ = @import("os/test.zig"); } /// Applications can override the `system` API layer in their root source file. /// Otherwise, when linking libc, this is the C API. /// When not linking libc, it is the OS-specific system interface. pub const system = if (@hasDecl(root, "os") and root.os != @This()) root.os.system else if (builtin.link_libc or is_windows) std.c else switch (builtin.os.tag) { .linux => linux, .wasi => wasi, .uefi => uefi, else => struct {}, }; pub const AF = system.AF; pub const AF_SUN = system.AF_SUN; pub const ARCH = system.ARCH; pub const AT = system.AT; pub const AT_SUN = system.AT_SUN; pub const CLOCK = system.CLOCK; pub const CPU_COUNT = system.CPU_COUNT; pub const CTL = system.CTL; pub const DT = system.DT; pub const E = system.E; pub const Elf_Symndx = system.Elf_Symndx; pub const F = system.F; pub const FD_CLOEXEC = system.FD_CLOEXEC; pub const Flock = system.Flock; pub const HOST_NAME_MAX = system.HOST_NAME_MAX; pub const IFNAMESIZE = system.IFNAMESIZE; pub const IOV_MAX = system.IOV_MAX; pub const IPPROTO = system.IPPROTO; pub const KERN = system.KERN; pub const Kevent = system.Kevent; pub const LOCK = system.LOCK; pub const MADV = system.MADV; pub const MAP = system.MAP; pub const MSF = system.MSF; pub const MAX_ADDR_LEN = system.MAX_ADDR_LEN; pub const MFD = system.MFD; pub const MMAP2_UNIT = system.MMAP2_UNIT; pub const MSG = system.MSG; pub const NAME_MAX = system.NAME_MAX; pub const O = switch (builtin.os.tag) { // We want to expose the POSIX-like OFLAGS, so we use std.c.wasi.O instead // of std.os.wasi.O, which is for non-POSIX-like `wasi.path_open`, etc. .wasi => std.c.O, else => system.O, }; pub const PATH_MAX = system.PATH_MAX; pub const POLL = system.POLL; pub const POSIX_FADV = system.POSIX_FADV; pub const PR = system.PR; pub const PROT = system.PROT; pub const REG = system.REG; pub const RIGHT = system.RIGHT; pub const RLIM = system.RLIM; pub const RR = system.RR; pub const S = system.S; pub const SA = system.SA; pub const SC = system.SC; pub const _SC = system._SC; pub const SEEK = system.SEEK; pub const SHUT = system.SHUT; pub const SIG = system.SIG; pub const SIOCGIFINDEX = system.SIOCGIFINDEX; pub const SO = system.SO; pub const SOCK = system.SOCK; pub const SOL = system.SOL; pub const STDERR_FILENO = system.STDERR_FILENO; pub const STDIN_FILENO = system.STDIN_FILENO; pub const STDOUT_FILENO = system.STDOUT_FILENO; pub const SYS = system.SYS; pub const Sigaction = system.Sigaction; pub const Stat = system.Stat; pub const TCSA = system.TCSA; pub const TCP = system.TCP; pub const VDSO = system.VDSO; pub const W = system.W; pub const addrinfo = system.addrinfo; pub const blkcnt_t = system.blkcnt_t; pub const blksize_t = system.blksize_t; pub const clock_t = system.clock_t; pub const cpu_set_t = system.cpu_set_t; pub const dev_t = system.dev_t; pub const dl_phdr_info = system.dl_phdr_info; pub const empty_sigset = system.empty_sigset; pub const fd_t = system.fd_t; pub const fdflags_t = system.fdflags_t; pub const fdstat_t = system.fdstat_t; pub const gid_t = system.gid_t; pub const ifreq = system.ifreq; pub const ino_t = system.ino_t; pub const lookupflags_t = system.lookupflags_t; pub const mcontext_t = system.mcontext_t; pub const mode_t = system.mode_t; pub const msghdr = system.msghdr; pub const msghdr_const = system.msghdr_const; pub const nfds_t = system.nfds_t; pub const nlink_t = system.nlink_t; pub const off_t = system.off_t; pub const oflags_t = system.oflags_t; pub const pid_t = system.pid_t; pub const pollfd = system.pollfd; pub const port_t = system.port_t; pub const port_event = system.port_event; pub const port_notify = system.port_notify; pub const file_obj = system.file_obj; pub const rights_t = system.rights_t; pub const rlim_t = system.rlim_t; pub const rlimit = system.rlimit; pub const rlimit_resource = system.rlimit_resource; pub const rusage = system.rusage; pub const sa_family_t = system.sa_family_t; pub const siginfo_t = system.siginfo_t; pub const sigset_t = system.sigset_t; pub const sockaddr = system.sockaddr; pub const socklen_t = system.socklen_t; pub const stack_t = system.stack_t; pub const tcflag_t = system.tcflag_t; pub const termios = system.termios; pub const time_t = system.time_t; pub const timespec = system.timespec; pub const timestamp_t = system.timestamp_t; pub const timeval = system.timeval; pub const timezone = system.timezone; pub const ucontext_t = system.ucontext_t; pub const uid_t = system.uid_t; pub const user_desc = system.user_desc; pub const utsname = system.utsname; pub const F_OK = system.F_OK; pub const R_OK = system.R_OK; pub const W_OK = system.W_OK; pub const X_OK = system.X_OK; pub const iovec = extern struct { iov_base: [*]u8, iov_len: usize, }; pub const iovec_const = extern struct { iov_base: [*]const u8, iov_len: usize, }; pub const LOG = struct { /// system is unusable pub const EMERG = 0; /// action must be taken immediately pub const ALERT = 1; /// critical conditions pub const CRIT = 2; /// error conditions pub const ERR = 3; /// warning conditions pub const WARNING = 4; /// normal but significant condition pub const NOTICE = 5; /// informational pub const INFO = 6; /// debug-level messages pub const DEBUG = 7; }; /// An fd-relative file path /// /// This is currently only used for WASI-specific functionality, but the concept /// is the same as the dirfd/pathname pairs in the `*at(...)` POSIX functions. pub const RelativePathWasi = struct { /// Handle to directory dir_fd: fd_t, /// Path to resource within `dir_fd`. relative_path: []const u8, }; pub const socket_t = if (builtin.os.tag == .windows) windows.ws2_32.SOCKET else fd_t; /// See also `getenv`. Populated by startup code before main(). /// TODO this is a footgun because the value will be undefined when using `zig build-lib`. /// https://github.com/ziglang/zig/issues/4524 pub var environ: [][*:0]u8 = undefined; /// Populated by startup code before main(). /// Not available on WASI or Windows without libc. See `std.process.argsAlloc` /// or `std.process.argsWithAllocator` for a cross-platform alternative. pub var argv: [][*:0]u8 = if (builtin.link_libc) undefined else switch (builtin.os.tag) { .windows => @compileError("argv isn't supported on Windows: use std.process.argsAlloc instead"), .wasi => @compileError("argv isn't supported on WASI: use std.process.argsAlloc instead"), else => undefined, }; /// To obtain errno, call this function with the return value of the /// system function call. For some systems this will obtain the value directly /// from the return code; for others it will use a thread-local errno variable. /// Therefore, this function only returns a well-defined value when it is called /// directly after the system function call which one wants to learn the errno /// value of. pub const errno = system.getErrno; /// Closes the file descriptor. /// This function is not capable of returning any indication of failure. An /// application which wants to ensure writes have succeeded before closing /// must call `fsync` before `close`. /// Note: The Zig standard library does not support POSIX thread cancellation. pub fn close(fd: fd_t) void { if (builtin.os.tag == .windows) { return windows.CloseHandle(fd); } if (builtin.os.tag == .wasi and !builtin.link_libc) { _ = wasi.fd_close(fd); return; } if (comptime builtin.target.isDarwin()) { // This avoids the EINTR problem. switch (darwin.getErrno(darwin.@"close$NOCANCEL"(fd))) { .BADF => unreachable, // Always a race condition. else => return, } } switch (errno(system.close(fd))) { .BADF => unreachable, // Always a race condition. .INTR => return, // This is still a success. See https://github.com/ziglang/zig/issues/2425 else => return, } } pub const FChmodError = error{ AccessDenied, InputOutput, SymLinkLoop, FileNotFound, SystemResources, ReadOnlyFileSystem, } || UnexpectedError; /// Changes the mode of the file referred to by the file descriptor. /// The process must have the correct privileges in order to do this /// successfully, or must have the effective user ID matching the owner /// of the file. pub fn fchmod(fd: fd_t, mode: mode_t) FChmodError!void { if (builtin.os.tag == .windows or builtin.os.tag == .wasi) @compileError("Unsupported OS"); while (true) { const res = system.fchmod(fd, mode); switch (system.getErrno(res)) { .SUCCESS => return, .INTR => continue, .BADF => unreachable, // Can be reached if the fd refers to a non-iterable directory. .FAULT => unreachable, .INVAL => unreachable, .ACCES => return error.AccessDenied, .IO => return error.InputOutput, .LOOP => return error.SymLinkLoop, .NOENT => return error.FileNotFound, .NOMEM => return error.SystemResources, .NOTDIR => return error.FileNotFound, .PERM => return error.AccessDenied, .ROFS => return error.ReadOnlyFileSystem, else => |err| return unexpectedErrno(err), } } } pub const FChownError = error{ AccessDenied, InputOutput, SymLinkLoop, FileNotFound, SystemResources, ReadOnlyFileSystem, } || UnexpectedError; /// Changes the owner and group of the file referred to by the file descriptor. /// The process must have the correct privileges in order to do this /// successfully. The group may be changed by the owner of the directory to /// any group of which the owner is a member. If the owner or group is /// specified as `null`, the ID is not changed. pub fn fchown(fd: fd_t, owner: ?uid_t, group: ?gid_t) FChownError!void { if (builtin.os.tag == .windows or builtin.os.tag == .wasi) @compileError("Unsupported OS"); while (true) { const res = system.fchown(fd, owner orelse @as(u32, 0) -% 1, group orelse @as(u32, 0) -% 1); switch (system.getErrno(res)) { .SUCCESS => return, .INTR => continue, .BADF => unreachable, // Can be reached if the fd refers to a non-iterable directory. .FAULT => unreachable, .INVAL => unreachable, .ACCES => return error.AccessDenied, .IO => return error.InputOutput, .LOOP => return error.SymLinkLoop, .NOENT => return error.FileNotFound, .NOMEM => return error.SystemResources, .NOTDIR => return error.FileNotFound, .PERM => return error.AccessDenied, .ROFS => return error.ReadOnlyFileSystem, else => |err| return unexpectedErrno(err), } } } pub const RebootError = error{ PermissionDenied, } || UnexpectedError; pub const RebootCommand = switch (builtin.os.tag) { .linux => union(linux.LINUX_REBOOT.CMD) { RESTART: void, HALT: void, CAD_ON: void, CAD_OFF: void, POWER_OFF: void, RESTART2: [*:0]const u8, SW_SUSPEND: void, KEXEC: void, }, else => @compileError("Unsupported OS"), }; pub fn reboot(cmd: RebootCommand) RebootError!void { switch (builtin.os.tag) { .linux => { switch (system.getErrno(linux.reboot( .MAGIC1, .MAGIC2, @as(linux.LINUX_REBOOT.CMD, cmd), switch (cmd) { .RESTART2 => |s| s, else => null, }, ))) { .SUCCESS => {}, .PERM => return error.PermissionDenied, else => |err| return std.os.unexpectedErrno(err), } switch (cmd) { .CAD_OFF => {}, .CAD_ON => {}, .SW_SUSPEND => {}, .HALT => unreachable, .KEXEC => unreachable, .POWER_OFF => unreachable, .RESTART => unreachable, .RESTART2 => unreachable, } }, else => @compileError("Unsupported OS"), } } pub const GetRandomError = OpenError; /// Obtain a series of random bytes. These bytes can be used to seed user-space /// random number generators or for cryptographic purposes. /// When linking against libc, this calls the /// appropriate OS-specific library call. Otherwise it uses the zig standard /// library implementation. pub fn getrandom(buffer: []u8) GetRandomError!void { if (builtin.os.tag == .windows) { return windows.RtlGenRandom(buffer); } if (builtin.os.tag == .linux or builtin.os.tag == .freebsd) { var buf = buffer; const use_c = builtin.os.tag != .linux or std.c.versionCheck(std.builtin.Version{ .major = 2, .minor = 25, .patch = 0 }).ok; while (buf.len != 0) { const res = if (use_c) blk: { const rc = std.c.getrandom(buf.ptr, buf.len, 0); break :blk .{ .num_read = @bitCast(usize, rc), .err = std.c.getErrno(rc), }; } else blk: { const rc = linux.getrandom(buf.ptr, buf.len, 0); break :blk .{ .num_read = rc, .err = linux.getErrno(rc), }; }; switch (res.err) { .SUCCESS => buf = buf[res.num_read..], .INVAL => unreachable, .FAULT => unreachable, .INTR => continue, .NOSYS => return getRandomBytesDevURandom(buf), else => return unexpectedErrno(res.err), } } return; } switch (builtin.os.tag) { .netbsd, .openbsd, .macos, .ios, .tvos, .watchos => { system.arc4random_buf(buffer.ptr, buffer.len); return; }, .wasi => switch (wasi.random_get(buffer.ptr, buffer.len)) { .SUCCESS => return, else => |err| return unexpectedErrno(err), }, else => return getRandomBytesDevURandom(buffer), } } fn getRandomBytesDevURandom(buf: []u8) !void { const fd = try openZ("/dev/urandom", O.RDONLY | O.CLOEXEC, 0); defer close(fd); const st = try fstat(fd); if (!S.ISCHR(st.mode)) { return error.NoDevice; } const file = std.fs.File{ .handle = fd, .capable_io_mode = .blocking, .intended_io_mode = .blocking, }; const stream = file.reader(); stream.readNoEof(buf) catch return error.Unexpected; } /// Causes abnormal process termination. /// If linking against libc, this calls the abort() libc function. Otherwise /// it raises SIGABRT followed by SIGKILL and finally lo /// Invokes the current signal handler for SIGABRT, if any. pub fn abort() noreturn { @setCold(true); // MSVCRT abort() sometimes opens a popup window which is undesirable, so // even when linking libc on Windows we use our own abort implementation. // See https://github.com/ziglang/zig/issues/2071 for more details. if (builtin.os.tag == .windows) { if (builtin.mode == .Debug) { @breakpoint(); } windows.kernel32.ExitProcess(3); } if (!builtin.link_libc and builtin.os.tag == .linux) { // The Linux man page says that the libc abort() function // "first unblocks the SIGABRT signal", but this is a footgun // for user-defined signal handlers that want to restore some state in // some program sections and crash in others. // So, the user-installed SIGABRT handler is run, if present. raise(SIG.ABRT) catch {}; // Disable all signal handlers. sigprocmask(SIG.BLOCK, &linux.all_mask, null); // Only one thread may proceed to the rest of abort(). if (!builtin.single_threaded) { const global = struct { var abort_entered: bool = false; }; while (@cmpxchgWeak(bool, &global.abort_entered, false, true, .SeqCst, .SeqCst)) |_| {} } // Install default handler so that the tkill below will terminate. const sigact = Sigaction{ .handler = .{ .handler = SIG.DFL }, .mask = empty_sigset, .flags = 0, }; sigaction(SIG.ABRT, &sigact, null) catch |err| switch (err) { error.OperationNotSupported => unreachable, }; _ = linux.tkill(linux.gettid(), SIG.ABRT); const sigabrtmask: linux.sigset_t = [_]u32{0} ** 31 ++ [_]u32{1 << (SIG.ABRT - 1)}; sigprocmask(SIG.UNBLOCK, &sigabrtmask, null); // Beyond this point should be unreachable. @intToPtr(*allowzero volatile u8, 0).* = 0; raise(SIG.KILL) catch {}; exit(127); // Pid 1 might not be signalled in some containers. } if (builtin.os.tag == .uefi) { exit(0); // TODO choose appropriate exit code } if (builtin.os.tag == .wasi) { @breakpoint(); exit(1); } if (builtin.os.tag == .cuda) { // TODO: introduce `@trap` instead of abusing https://github.com/ziglang/zig/issues/2291 @"llvm.trap"(); } system.abort(); } extern fn @"llvm.trap"() noreturn; pub const RaiseError = UnexpectedError; pub fn raise(sig: u8) RaiseError!void { if (builtin.link_libc) { switch (errno(system.raise(sig))) { .SUCCESS => return, else => |err| return unexpectedErrno(err), } } if (builtin.os.tag == .linux) { var set: sigset_t = undefined; // block application signals sigprocmask(SIG.BLOCK, &linux.app_mask, &set); const tid = linux.gettid(); const rc = linux.tkill(tid, sig); // restore signal mask sigprocmask(SIG.SETMASK, &set, null); switch (errno(rc)) { .SUCCESS => return, else => |err| return unexpectedErrno(err), } } @compileError("std.os.raise unimplemented for this target"); } pub const KillError = error{PermissionDenied} || UnexpectedError; pub fn kill(pid: pid_t, sig: u8) KillError!void { switch (errno(system.kill(pid, sig))) { .SUCCESS => return, .INVAL => unreachable, // invalid signal .PERM => return error.PermissionDenied, .SRCH => unreachable, // always a race condition else => |err| return unexpectedErrno(err), } } /// Exits the program cleanly with the specified status code. pub fn exit(status: u8) noreturn { if (builtin.link_libc) { system.exit(status); } if (builtin.os.tag == .windows) { windows.kernel32.ExitProcess(status); } if (builtin.os.tag == .wasi) { wasi.proc_exit(status); } if (builtin.os.tag == .linux and !builtin.single_threaded) { linux.exit_group(status); } if (builtin.os.tag == .uefi) { // exit() is only avaliable if exitBootServices() has not been called yet. // This call to exit should not fail, so we don't care about its return value. if (uefi.system_table.boot_services) |bs| { _ = bs.exit(uefi.handle, @intToEnum(uefi.Status, status), 0, null); } // If we can't exit, reboot the system instead. uefi.system_table.runtime_services.resetSystem(uefi.tables.ResetType.ResetCold, @intToEnum(uefi.Status, status), 0, null); } system.exit(status); } pub const ReadError = error{ InputOutput, SystemResources, IsDir, OperationAborted, BrokenPipe, ConnectionResetByPeer, ConnectionTimedOut, NotOpenForReading, /// This error occurs when no global event loop is configured, /// and reading from the file descriptor would block. WouldBlock, /// In WASI, this error occurs when the file descriptor does /// not hold the required rights to read from it. AccessDenied, } || UnexpectedError; /// Returns the number of bytes that were read, which can be less than /// buf.len. If 0 bytes were read, that means EOF. /// If `fd` is opened in non blocking mode, the function will return error.WouldBlock /// when EAGAIN is received. /// /// Linux has a limit on how many bytes may be transferred in one `read` call, which is `0x7ffff000` /// on both 64-bit and 32-bit systems. This is due to using a signed C int as the return value, as /// well as stuffing the errno codes into the last `4096` values. This is noted on the `read` man page. /// The limit on Darwin is `0x7fffffff`, trying to read more than that returns EINVAL. /// The corresponding POSIX limit is `math.maxInt(isize)`. pub fn read(fd: fd_t, buf: []u8) ReadError!usize { if (builtin.os.tag == .windows) { return windows.ReadFile(fd, buf, null, std.io.default_mode); } if (builtin.os.tag == .wasi and !builtin.link_libc) { const iovs = [1]iovec{iovec{ .iov_base = buf.ptr, .iov_len = buf.len, }}; var nread: usize = undefined; switch (wasi.fd_read(fd, &iovs, iovs.len, &nread)) { .SUCCESS => return nread, .INTR => unreachable, .INVAL => unreachable, .FAULT => unreachable, .AGAIN => unreachable, .BADF => return error.NotOpenForReading, // Can be a race condition. .IO => return error.InputOutput, .ISDIR => return error.IsDir, .NOBUFS => return error.SystemResources, .NOMEM => return error.SystemResources, .CONNRESET => return error.ConnectionResetByPeer, .TIMEDOUT => return error.ConnectionTimedOut, .NOTCAPABLE => return error.AccessDenied, else => |err| return unexpectedErrno(err), } } // Prevents EINVAL. const max_count = switch (builtin.os.tag) { .linux => 0x7ffff000, .macos, .ios, .watchos, .tvos => math.maxInt(i32), else => math.maxInt(isize), }; const adjusted_len = @min(max_count, buf.len); while (true) { const rc = system.read(fd, buf.ptr, adjusted_len); switch (errno(rc)) { .SUCCESS => return @intCast(usize, rc), .INTR => continue, .INVAL => unreachable, .FAULT => unreachable, .AGAIN => return error.WouldBlock, .BADF => return error.NotOpenForReading, // Can be a race condition. .IO => return error.InputOutput, .ISDIR => return error.IsDir, .NOBUFS => return error.SystemResources, .NOMEM => return error.SystemResources, .CONNRESET => return error.ConnectionResetByPeer, .TIMEDOUT => return error.ConnectionTimedOut, else => |err| return unexpectedErrno(err), } } } /// Number of bytes read is returned. Upon reading end-of-file, zero is returned. /// /// For POSIX systems, if `fd` is opened in non blocking mode, the function will /// return error.WouldBlock when EAGAIN is received. /// On Windows, if the application has a global event loop enabled, I/O Completion Ports are /// used to perform the I/O. `error.WouldBlock` is not possible on Windows. /// /// This operation is non-atomic on the following systems: /// * Windows /// On these systems, the read races with concurrent writes to the same file descriptor. pub fn readv(fd: fd_t, iov: []const iovec) ReadError!usize { if (builtin.os.tag == .windows) { // TODO improve this to use ReadFileScatter if (iov.len == 0) return @as(usize, 0); const first = iov[0]; return read(fd, first.iov_base[0..first.iov_len]); } if (builtin.os.tag == .wasi and !builtin.link_libc) { var nread: usize = undefined; switch (wasi.fd_read(fd, iov.ptr, iov.len, &nread)) { .SUCCESS => return nread, .INTR => unreachable, .INVAL => unreachable, .FAULT => unreachable, .AGAIN => unreachable, // currently not support in WASI .BADF => return error.NotOpenForReading, // can be a race condition .IO => return error.InputOutput, .ISDIR => return error.IsDir, .NOBUFS => return error.SystemResources, .NOMEM => return error.SystemResources, .NOTCAPABLE => return error.AccessDenied, else => |err| return unexpectedErrno(err), } } const iov_count = math.cast(u31, iov.len) orelse math.maxInt(u31); while (true) { // TODO handle the case when iov_len is too large and get rid of this @intCast const rc = system.readv(fd, iov.ptr, iov_count); switch (errno(rc)) { .SUCCESS => return @intCast(usize, rc), .INTR => continue, .INVAL => unreachable, .FAULT => unreachable, .AGAIN => return error.WouldBlock, .BADF => return error.NotOpenForReading, // can be a race condition .IO => return error.InputOutput, .ISDIR => return error.IsDir, .NOBUFS => return error.SystemResources, .NOMEM => return error.SystemResources, else => |err| return unexpectedErrno(err), } } } pub const PReadError = ReadError || error{Unseekable}; /// Number of bytes read is returned. Upon reading end-of-file, zero is returned. /// /// Retries when interrupted by a signal. /// /// For POSIX systems, if `fd` is opened in non blocking mode, the function will /// return error.WouldBlock when EAGAIN is received. /// On Windows, if the application has a global event loop enabled, I/O Completion Ports are /// used to perform the I/O. `error.WouldBlock` is not possible on Windows. /// /// Linux has a limit on how many bytes may be transferred in one `pread` call, which is `0x7ffff000` /// on both 64-bit and 32-bit systems. This is due to using a signed C int as the return value, as /// well as stuffing the errno codes into the last `4096` values. This is noted on the `read` man page. /// The limit on Darwin is `0x7fffffff`, trying to read more than that returns EINVAL. /// The corresponding POSIX limit is `math.maxInt(isize)`. pub fn pread(fd: fd_t, buf: []u8, offset: u64) PReadError!usize { if (builtin.os.tag == .windows) { return windows.ReadFile(fd, buf, offset, std.io.default_mode); } if (builtin.os.tag == .wasi and !builtin.link_libc) { const iovs = [1]iovec{iovec{ .iov_base = buf.ptr, .iov_len = buf.len, }}; var nread: usize = undefined; switch (wasi.fd_pread(fd, &iovs, iovs.len, offset, &nread)) { .SUCCESS => return nread, .INTR => unreachable, .INVAL => unreachable, .FAULT => unreachable, .AGAIN => unreachable, .BADF => return error.NotOpenForReading, // Can be a race condition. .IO => return error.InputOutput, .ISDIR => return error.IsDir, .NOBUFS => return error.SystemResources, .NOMEM => return error.SystemResources, .CONNRESET => return error.ConnectionResetByPeer, .NXIO => return error.Unseekable, .SPIPE => return error.Unseekable, .OVERFLOW => return error.Unseekable, .NOTCAPABLE => return error.AccessDenied, else => |err| return unexpectedErrno(err), } } // Prevent EINVAL. const max_count = switch (builtin.os.tag) { .linux => 0x7ffff000, .macos, .ios, .watchos, .tvos => math.maxInt(i32), else => math.maxInt(isize), }; const adjusted_len = @min(max_count, buf.len); const pread_sym = if (builtin.os.tag == .linux and builtin.link_libc) system.pread64 else system.pread; const ioffset = @bitCast(i64, offset); // the OS treats this as unsigned while (true) { const rc = pread_sym(fd, buf.ptr, adjusted_len, ioffset); switch (errno(rc)) { .SUCCESS => return @intCast(usize, rc), .INTR => continue, .INVAL => unreachable, .FAULT => unreachable, .AGAIN => return error.WouldBlock, .BADF => return error.NotOpenForReading, // Can be a race condition. .IO => return error.InputOutput, .ISDIR => return error.IsDir, .NOBUFS => return error.SystemResources, .NOMEM => return error.SystemResources, .CONNRESET => return error.ConnectionResetByPeer, .NXIO => return error.Unseekable, .SPIPE => return error.Unseekable, .OVERFLOW => return error.Unseekable, else => |err| return unexpectedErrno(err), } } } pub const TruncateError = error{ FileTooBig, InputOutput, FileBusy, /// In WASI, this error occurs when the file descriptor does /// not hold the required rights to call `ftruncate` on it. AccessDenied, } || UnexpectedError; pub fn ftruncate(fd: fd_t, length: u64) TruncateError!void { if (builtin.os.tag == .windows) { var io_status_block: windows.IO_STATUS_BLOCK = undefined; var eof_info = windows.FILE_END_OF_FILE_INFORMATION{ .EndOfFile = @bitCast(windows.LARGE_INTEGER, length), }; const rc = windows.ntdll.NtSetInformationFile( fd, &io_status_block, &eof_info, @sizeOf(windows.FILE_END_OF_FILE_INFORMATION), .FileEndOfFileInformation, ); switch (rc) { .SUCCESS => return, .INVALID_HANDLE => unreachable, // Handle not open for writing .ACCESS_DENIED => return error.AccessDenied, else => return windows.unexpectedStatus(rc), } } if (builtin.os.tag == .wasi and !builtin.link_libc) { switch (wasi.fd_filestat_set_size(fd, length)) { .SUCCESS => return, .INTR => unreachable, .FBIG => return error.FileTooBig, .IO => return error.InputOutput, .PERM => return error.AccessDenied, .TXTBSY => return error.FileBusy, .BADF => unreachable, // Handle not open for writing .INVAL => unreachable, // Handle not open for writing .NOTCAPABLE => return error.AccessDenied, else => |err| return unexpectedErrno(err), } } while (true) { const ftruncate_sym = if (builtin.os.tag == .linux and builtin.link_libc) system.ftruncate64 else system.ftruncate; const ilen = @bitCast(i64, length); // the OS treats this as unsigned switch (errno(ftruncate_sym(fd, ilen))) { .SUCCESS => return, .INTR => continue, .FBIG => return error.FileTooBig, .IO => return error.InputOutput, .PERM => return error.AccessDenied, .TXTBSY => return error.FileBusy, .BADF => unreachable, // Handle not open for writing .INVAL => unreachable, // Handle not open for writing else => |err| return unexpectedErrno(err), } } } /// Number of bytes read is returned. Upon reading end-of-file, zero is returned. /// /// Retries when interrupted by a signal. /// /// For POSIX systems, if `fd` is opened in non blocking mode, the function will /// return error.WouldBlock when EAGAIN is received. /// On Windows, if the application has a global event loop enabled, I/O Completion Ports are /// used to perform the I/O. `error.WouldBlock` is not possible on Windows. /// /// This operation is non-atomic on the following systems: /// * Darwin /// * Windows /// On these systems, the read races with concurrent writes to the same file descriptor. pub fn preadv(fd: fd_t, iov: []const iovec, offset: u64) PReadError!usize { const have_pread_but_not_preadv = switch (builtin.os.tag) { .windows, .macos, .ios, .watchos, .tvos, .haiku => true, else => false, }; if (have_pread_but_not_preadv) { // We could loop here; but proper usage of `preadv` must handle partial reads anyway. // So we simply read into the first vector only. if (iov.len == 0) return @as(usize, 0); const first = iov[0]; return pread(fd, first.iov_base[0..first.iov_len], offset); } if (builtin.os.tag == .wasi and !builtin.link_libc) { var nread: usize = undefined; switch (wasi.fd_pread(fd, iov.ptr, iov.len, offset, &nread)) { .SUCCESS => return nread, .INTR => unreachable, .INVAL => unreachable, .FAULT => unreachable, .AGAIN => unreachable, .BADF => return error.NotOpenForReading, // can be a race condition .IO => return error.InputOutput, .ISDIR => return error.IsDir, .NOBUFS => return error.SystemResources, .NOMEM => return error.SystemResources, .NXIO => return error.Unseekable, .SPIPE => return error.Unseekable, .OVERFLOW => return error.Unseekable, .NOTCAPABLE => return error.AccessDenied, else => |err| return unexpectedErrno(err), } } const iov_count = math.cast(u31, iov.len) orelse math.maxInt(u31); const preadv_sym = if (builtin.os.tag == .linux and builtin.link_libc) system.preadv64 else system.preadv; const ioffset = @bitCast(i64, offset); // the OS treats this as unsigned while (true) { const rc = preadv_sym(fd, iov.ptr, iov_count, ioffset); switch (errno(rc)) { .SUCCESS => return @bitCast(usize, rc), .INTR => continue, .INVAL => unreachable, .FAULT => unreachable, .AGAIN => return error.WouldBlock, .BADF => return error.NotOpenForReading, // can be a race condition .IO => return error.InputOutput, .ISDIR => return error.IsDir, .NOBUFS => return error.SystemResources, .NOMEM => return error.SystemResources, .NXIO => return error.Unseekable, .SPIPE => return error.Unseekable, .OVERFLOW => return error.Unseekable, else => |err| return unexpectedErrno(err), } } } pub const WriteError = error{ DiskQuota, FileTooBig, InputOutput, NoSpaceLeft, /// In WASI, this error may occur when the file descriptor does /// not hold the required rights to write to it. AccessDenied, BrokenPipe, SystemResources, OperationAborted, NotOpenForWriting, /// The process cannot access the file because another process has locked /// a portion of the file. Windows-only. LockViolation, /// This error occurs when no global event loop is configured, /// and reading from the file descriptor would block. WouldBlock, /// Connection reset by peer. ConnectionResetByPeer, } || UnexpectedError; /// Write to a file descriptor. /// Retries when interrupted by a signal. /// Returns the number of bytes written. If nonzero bytes were supplied, this will be nonzero. /// /// Note that a successful write() may transfer fewer than count bytes. Such partial writes can /// occur for various reasons; for example, because there was insufficient space on the disk /// device to write all of the requested bytes, or because a blocked write() to a socket, pipe, or /// similar was interrupted by a signal handler after it had transferred some, but before it had /// transferred all of the requested bytes. In the event of a partial write, the caller can make /// another write() call to transfer the remaining bytes. The subsequent call will either /// transfer further bytes or may result in an error (e.g., if the disk is now full). /// /// For POSIX systems, if `fd` is opened in non blocking mode, the function will /// return error.WouldBlock when EAGAIN is received. /// On Windows, if the application has a global event loop enabled, I/O Completion Ports are /// used to perform the I/O. `error.WouldBlock` is not possible on Windows. /// /// Linux has a limit on how many bytes may be transferred in one `write` call, which is `0x7ffff000` /// on both 64-bit and 32-bit systems. This is due to using a signed C int as the return value, as /// well as stuffing the errno codes into the last `4096` values. This is noted on the `write` man page. /// The limit on Darwin is `0x7fffffff`, trying to read more than that returns EINVAL. /// The corresponding POSIX limit is `math.maxInt(isize)`. pub fn write(fd: fd_t, bytes: []const u8) WriteError!usize { if (builtin.os.tag == .windows) { return windows.WriteFile(fd, bytes, null, std.io.default_mode); } if (builtin.os.tag == .wasi and !builtin.link_libc) { const ciovs = [_]iovec_const{iovec_const{ .iov_base = bytes.ptr, .iov_len = bytes.len, }}; var nwritten: usize = undefined; switch (wasi.fd_write(fd, &ciovs, ciovs.len, &nwritten)) { .SUCCESS => return nwritten, .INTR => unreachable, .INVAL => unreachable, .FAULT => unreachable, .AGAIN => unreachable, .BADF => return error.NotOpenForWriting, // can be a race condition. .DESTADDRREQ => unreachable, // `connect` was never called. .DQUOT => return error.DiskQuota, .FBIG => return error.FileTooBig, .IO => return error.InputOutput, .NOSPC => return error.NoSpaceLeft, .PERM => return error.AccessDenied, .PIPE => return error.BrokenPipe, .NOTCAPABLE => return error.AccessDenied, else => |err| return unexpectedErrno(err), } } const max_count = switch (builtin.os.tag) { .linux => 0x7ffff000, .macos, .ios, .watchos, .tvos => math.maxInt(i32), else => math.maxInt(isize), }; const adjusted_len = @min(max_count, bytes.len); while (true) { const rc = system.write(fd, bytes.ptr, adjusted_len); switch (errno(rc)) { .SUCCESS => return @intCast(usize, rc), .INTR => continue, .INVAL => unreachable, .FAULT => unreachable, .AGAIN => return error.WouldBlock, .BADF => return error.NotOpenForWriting, // can be a race condition. .DESTADDRREQ => unreachable, // `connect` was never called. .DQUOT => return error.DiskQuota, .FBIG => return error.FileTooBig, .IO => return error.InputOutput, .NOSPC => return error.NoSpaceLeft, .PERM => return error.AccessDenied, .PIPE => return error.BrokenPipe, .CONNRESET => return error.ConnectionResetByPeer, else => |err| return unexpectedErrno(err), } } } /// Write multiple buffers to a file descriptor. /// Retries when interrupted by a signal. /// Returns the number of bytes written. If nonzero bytes were supplied, this will be nonzero. /// /// Note that a successful write() may transfer fewer bytes than supplied. Such partial writes can /// occur for various reasons; for example, because there was insufficient space on the disk /// device to write all of the requested bytes, or because a blocked write() to a socket, pipe, or /// similar was interrupted by a signal handler after it had transferred some, but before it had /// transferred all of the requested bytes. In the event of a partial write, the caller can make /// another write() call to transfer the remaining bytes. The subsequent call will either /// transfer further bytes or may result in an error (e.g., if the disk is now full). /// /// For POSIX systems, if `fd` is opened in non blocking mode, the function will /// return error.WouldBlock when EAGAIN is received. /// On Windows, if the application has a global event loop enabled, I/O Completion Ports are /// used to perform the I/O. `error.WouldBlock` is not possible on Windows. /// /// If `iov.len` is larger than `IOV_MAX`, a partial write will occur. pub fn writev(fd: fd_t, iov: []const iovec_const) WriteError!usize { if (builtin.os.tag == .windows) { // TODO improve this to use WriteFileScatter if (iov.len == 0) return @as(usize, 0); const first = iov[0]; return write(fd, first.iov_base[0..first.iov_len]); } if (builtin.os.tag == .wasi and !builtin.link_libc) { var nwritten: usize = undefined; switch (wasi.fd_write(fd, iov.ptr, iov.len, &nwritten)) { .SUCCESS => return nwritten, .INTR => unreachable, .INVAL => unreachable, .FAULT => unreachable, .AGAIN => unreachable, .BADF => return error.NotOpenForWriting, // can be a race condition. .DESTADDRREQ => unreachable, // `connect` was never called. .DQUOT => return error.DiskQuota, .FBIG => return error.FileTooBig, .IO => return error.InputOutput, .NOSPC => return error.NoSpaceLeft, .PERM => return error.AccessDenied, .PIPE => return error.BrokenPipe, .NOTCAPABLE => return error.AccessDenied, else => |err| return unexpectedErrno(err), } } const iov_count = if (iov.len > IOV_MAX) IOV_MAX else @intCast(u31, iov.len); while (true) { const rc = system.writev(fd, iov.ptr, iov_count); switch (errno(rc)) { .SUCCESS => return @intCast(usize, rc), .INTR => continue, .INVAL => unreachable, .FAULT => unreachable, .AGAIN => return error.WouldBlock, .BADF => return error.NotOpenForWriting, // Can be a race condition. .DESTADDRREQ => unreachable, // `connect` was never called. .DQUOT => return error.DiskQuota, .FBIG => return error.FileTooBig, .IO => return error.InputOutput, .NOSPC => return error.NoSpaceLeft, .PERM => return error.AccessDenied, .PIPE => return error.BrokenPipe, .CONNRESET => return error.ConnectionResetByPeer, else => |err| return unexpectedErrno(err), } } } pub const PWriteError = WriteError || error{Unseekable}; /// Write to a file descriptor, with a position offset. /// Retries when interrupted by a signal. /// Returns the number of bytes written. If nonzero bytes were supplied, this will be nonzero. /// /// Note that a successful write() may transfer fewer bytes than supplied. Such partial writes can /// occur for various reasons; for example, because there was insufficient space on the disk /// device to write all of the requested bytes, or because a blocked write() to a socket, pipe, or /// similar was interrupted by a signal handler after it had transferred some, but before it had /// transferred all of the requested bytes. In the event of a partial write, the caller can make /// another write() call to transfer the remaining bytes. The subsequent call will either /// transfer further bytes or may result in an error (e.g., if the disk is now full). /// /// For POSIX systems, if `fd` is opened in non blocking mode, the function will /// return error.WouldBlock when EAGAIN is received. /// On Windows, if the application has a global event loop enabled, I/O Completion Ports are /// used to perform the I/O. `error.WouldBlock` is not possible on Windows. /// /// Linux has a limit on how many bytes may be transferred in one `pwrite` call, which is `0x7ffff000` /// on both 64-bit and 32-bit systems. This is due to using a signed C int as the return value, as /// well as stuffing the errno codes into the last `4096` values. This is noted on the `write` man page. /// The limit on Darwin is `0x7fffffff`, trying to write more than that returns EINVAL. /// The corresponding POSIX limit is `math.maxInt(isize)`. pub fn pwrite(fd: fd_t, bytes: []const u8, offset: u64) PWriteError!usize { if (builtin.os.tag == .windows) { return windows.WriteFile(fd, bytes, offset, std.io.default_mode); } if (builtin.os.tag == .wasi and !builtin.link_libc) { const ciovs = [1]iovec_const{iovec_const{ .iov_base = bytes.ptr, .iov_len = bytes.len, }}; var nwritten: usize = undefined; switch (wasi.fd_pwrite(fd, &ciovs, ciovs.len, offset, &nwritten)) { .SUCCESS => return nwritten, .INTR => unreachable, .INVAL => unreachable, .FAULT => unreachable, .AGAIN => unreachable, .BADF => return error.NotOpenForWriting, // can be a race condition. .DESTADDRREQ => unreachable, // `connect` was never called. .DQUOT => return error.DiskQuota, .FBIG => return error.FileTooBig, .IO => return error.InputOutput, .NOSPC => return error.NoSpaceLeft, .PERM => return error.AccessDenied, .PIPE => return error.BrokenPipe, .NXIO => return error.Unseekable, .SPIPE => return error.Unseekable, .OVERFLOW => return error.Unseekable, .NOTCAPABLE => return error.AccessDenied, else => |err| return unexpectedErrno(err), } } // Prevent EINVAL. const max_count = switch (builtin.os.tag) { .linux => 0x7ffff000, .macos, .ios, .watchos, .tvos => math.maxInt(i32), else => math.maxInt(isize), }; const adjusted_len = @min(max_count, bytes.len); const pwrite_sym = if (builtin.os.tag == .linux and builtin.link_libc) system.pwrite64 else system.pwrite; const ioffset = @bitCast(i64, offset); // the OS treats this as unsigned while (true) { const rc = pwrite_sym(fd, bytes.ptr, adjusted_len, ioffset); switch (errno(rc)) { .SUCCESS => return @intCast(usize, rc), .INTR => continue, .INVAL => unreachable, .FAULT => unreachable, .AGAIN => return error.WouldBlock, .BADF => return error.NotOpenForWriting, // Can be a race condition. .DESTADDRREQ => unreachable, // `connect` was never called. .DQUOT => return error.DiskQuota, .FBIG => return error.FileTooBig, .IO => return error.InputOutput, .NOSPC => return error.NoSpaceLeft, .PERM => return error.AccessDenied, .PIPE => return error.BrokenPipe, .NXIO => return error.Unseekable, .SPIPE => return error.Unseekable, .OVERFLOW => return error.Unseekable, else => |err| return unexpectedErrno(err), } } } /// Write multiple buffers to a file descriptor, with a position offset. /// Retries when interrupted by a signal. /// Returns the number of bytes written. If nonzero bytes were supplied, this will be nonzero. /// /// Note that a successful write() may transfer fewer than count bytes. Such partial writes can /// occur for various reasons; for example, because there was insufficient space on the disk /// device to write all of the requested bytes, or because a blocked write() to a socket, pipe, or /// similar was interrupted by a signal handler after it had transferred some, but before it had /// transferred all of the requested bytes. In the event of a partial write, the caller can make /// another write() call to transfer the remaining bytes. The subsequent call will either /// transfer further bytes or may result in an error (e.g., if the disk is now full). /// /// If `fd` is opened in non blocking mode, the function will /// return error.WouldBlock when EAGAIN is received. /// /// The following systems do not have this syscall, and will return partial writes if more than one /// vector is provided: /// * Darwin /// * Windows /// /// If `iov.len` is larger than `IOV_MAX`, a partial write will occur. pub fn pwritev(fd: fd_t, iov: []const iovec_const, offset: u64) PWriteError!usize { const have_pwrite_but_not_pwritev = switch (builtin.os.tag) { .windows, .macos, .ios, .watchos, .tvos, .haiku => true, else => false, }; if (have_pwrite_but_not_pwritev) { // We could loop here; but proper usage of `pwritev` must handle partial writes anyway. // So we simply write the first vector only. if (iov.len == 0) return @as(usize, 0); const first = iov[0]; return pwrite(fd, first.iov_base[0..first.iov_len], offset); } if (builtin.os.tag == .wasi and !builtin.link_libc) { var nwritten: usize = undefined; switch (wasi.fd_pwrite(fd, iov.ptr, iov.len, offset, &nwritten)) { .SUCCESS => return nwritten, .INTR => unreachable, .INVAL => unreachable, .FAULT => unreachable, .AGAIN => unreachable, .BADF => return error.NotOpenForWriting, // Can be a race condition. .DESTADDRREQ => unreachable, // `connect` was never called. .DQUOT => return error.DiskQuota, .FBIG => return error.FileTooBig, .IO => return error.InputOutput, .NOSPC => return error.NoSpaceLeft, .PERM => return error.AccessDenied, .PIPE => return error.BrokenPipe, .NXIO => return error.Unseekable, .SPIPE => return error.Unseekable, .OVERFLOW => return error.Unseekable, .NOTCAPABLE => return error.AccessDenied, else => |err| return unexpectedErrno(err), } } const pwritev_sym = if (builtin.os.tag == .linux and builtin.link_libc) system.pwritev64 else system.pwritev; const iov_count = if (iov.len > IOV_MAX) IOV_MAX else @intCast(u31, iov.len); const ioffset = @bitCast(i64, offset); // the OS treats this as unsigned while (true) { const rc = pwritev_sym(fd, iov.ptr, iov_count, ioffset); switch (errno(rc)) { .SUCCESS => return @intCast(usize, rc), .INTR => continue, .INVAL => unreachable, .FAULT => unreachable, .AGAIN => return error.WouldBlock, .BADF => return error.NotOpenForWriting, // Can be a race condition. .DESTADDRREQ => unreachable, // `connect` was never called. .DQUOT => return error.DiskQuota, .FBIG => return error.FileTooBig, .IO => return error.InputOutput, .NOSPC => return error.NoSpaceLeft, .PERM => return error.AccessDenied, .PIPE => return error.BrokenPipe, .NXIO => return error.Unseekable, .SPIPE => return error.Unseekable, .OVERFLOW => return error.Unseekable, else => |err| return unexpectedErrno(err), } } } pub const OpenError = error{ /// In WASI, this error may occur when the provided file handle is invalid. InvalidHandle, /// In WASI, this error may occur when the file descriptor does /// not hold the required rights to open a new resource relative to it. AccessDenied, SymLinkLoop, ProcessFdQuotaExceeded, SystemFdQuotaExceeded, NoDevice, FileNotFound, /// The path exceeded `MAX_PATH_BYTES` bytes. NameTooLong, /// Insufficient kernel memory was available, or /// the named file is a FIFO and per-user hard limit on /// memory allocation for pipes has been reached. SystemResources, /// The file is too large to be opened. This error is unreachable /// for 64-bit targets, as well as when opening directories. FileTooBig, /// The path refers to directory but the `O.DIRECTORY` flag was not provided. IsDir, /// A new path cannot be created because the device has no room for the new file. /// This error is only reachable when the `O.CREAT` flag is provided. NoSpaceLeft, /// A component used as a directory in the path was not, in fact, a directory, or /// `O.DIRECTORY` was specified and the path was not a directory. NotDir, /// The path already exists and the `O.CREAT` and `O.EXCL` flags were provided. PathAlreadyExists, DeviceBusy, /// The underlying filesystem does not support file locks FileLocksNotSupported, BadPathName, InvalidUtf8, /// One of these three things: /// * pathname refers to an executable image which is currently being /// executed and write access was requested. /// * pathname refers to a file that is currently in use as a swap /// file, and the O_TRUNC flag was specified. /// * pathname refers to a file that is currently being read by the /// kernel (e.g., for module/firmware loading), and write access was /// requested. FileBusy, WouldBlock, } || UnexpectedError; /// Open and possibly create a file. Keeps trying if it gets interrupted. /// See also `openZ`. pub fn open(file_path: []const u8, flags: u32, perm: mode_t) OpenError!fd_t { if (builtin.os.tag == .windows) { const file_path_w = try windows.sliceToPrefixedFileW(file_path); return openW(file_path_w.span(), flags, perm); } else if (builtin.os.tag == .wasi and !builtin.link_libc) { return openat(wasi.AT.FDCWD, file_path, flags, perm); } const file_path_c = try toPosixPath(file_path); return openZ(&file_path_c, flags, perm); } /// Open and possibly create a file. Keeps trying if it gets interrupted. /// See also `open`. pub fn openZ(file_path: [*:0]const u8, flags: u32, perm: mode_t) OpenError!fd_t { if (builtin.os.tag == .windows) { const file_path_w = try windows.cStrToPrefixedFileW(file_path); return openW(file_path_w.span(), flags, perm); } else if (builtin.os.tag == .wasi and !builtin.link_libc) { return open(mem.sliceTo(file_path, 0), flags, perm); } const open_sym = if (builtin.os.tag == .linux and builtin.link_libc) system.open64 else system.open; while (true) { const rc = open_sym(file_path, flags, perm); switch (errno(rc)) { .SUCCESS => return @intCast(fd_t, rc), .INTR => continue, .FAULT => unreachable, .INVAL => unreachable, .ACCES => return error.AccessDenied, .FBIG => return error.FileTooBig, .OVERFLOW => return error.FileTooBig, .ISDIR => return error.IsDir, .LOOP => return error.SymLinkLoop, .MFILE => return error.ProcessFdQuotaExceeded, .NAMETOOLONG => return error.NameTooLong, .NFILE => return error.SystemFdQuotaExceeded, .NODEV => return error.NoDevice, .NOENT => return error.FileNotFound, .NOMEM => return error.SystemResources, .NOSPC => return error.NoSpaceLeft, .NOTDIR => return error.NotDir, .PERM => return error.AccessDenied, .EXIST => return error.PathAlreadyExists, .BUSY => return error.DeviceBusy, else => |err| return unexpectedErrno(err), } } } fn openOptionsFromFlagsWindows(flags: u32) windows.OpenFileOptions { const w = windows; var access_mask: w.ULONG = w.READ_CONTROL | w.FILE_WRITE_ATTRIBUTES | w.SYNCHRONIZE; if (flags & O.RDWR != 0) { access_mask |= w.GENERIC_READ | w.GENERIC_WRITE; } else if (flags & O.WRONLY != 0) { access_mask |= w.GENERIC_WRITE; } else { access_mask |= w.GENERIC_READ | w.GENERIC_WRITE; } const filter: windows.OpenFileOptions.Filter = if (flags & O.DIRECTORY != 0) .dir_only else .file_only; const follow_symlinks: bool = flags & O.NOFOLLOW == 0; const creation: w.ULONG = blk: { if (flags & O.CREAT != 0) { if (flags & O.EXCL != 0) { break :blk w.FILE_CREATE; } } break :blk w.FILE_OPEN; }; return .{ .access_mask = access_mask, .io_mode = .blocking, .creation = creation, .filter = filter, .follow_symlinks = follow_symlinks, }; } /// Windows-only. The path parameter is /// [WTF-16](https://simonsapin.github.io/wtf-8/#potentially-ill-formed-utf-16) encoded. /// Translates the POSIX open API call to a Windows API call. /// TODO currently, this function does not handle all flag combinations /// or makes use of perm argument. pub fn openW(file_path_w: []const u16, flags: u32, perm: mode_t) OpenError!fd_t { _ = perm; var options = openOptionsFromFlagsWindows(flags); options.dir = std.fs.cwd().fd; return windows.OpenFile(file_path_w, options) catch |err| switch (err) { error.WouldBlock => unreachable, error.PipeBusy => unreachable, else => |e| return e, }; } var wasi_cwd = if (builtin.os.tag == .wasi and !builtin.link_libc) struct { // List of available Preopens preopens: ?PreopenList = null, // Memory buffer for storing the relative portion of the CWD path_buffer: [MAX_PATH_BYTES]u8 = undefined, // The absolute path associated with the current working directory cwd: []const u8 = "/", }{} else undefined; /// Initialize the available Preopen list on WASI and set the CWD to `cwd_init`. /// Note that `cwd_init` corresponds to a Preopen directory, not necessarily /// a POSIX path. For example, "." matches a Preopen provided with `--dir=.` /// /// This must be called before using any relative or absolute paths with `std.os` /// functions, if you are on WASI without linking libc. /// /// The current working directory is initialized to `cwd_root`, and `cwd_root` /// is inserted as a prefix for any Preopens whose dir begins with "." /// For example: /// "./foo/bar" - canonicalizes to -> "{cwd_root}/foo/bar" /// "foo/bar" - canonicalizes to -> "/foo/bar" /// "/foo/bar" - canonicalizes to -> "/foo/bar" /// /// `cwd_root` must be an absolute path. For initialization behavior similar to /// wasi-libc, use "/" as the `cwd_root` /// /// `alloc` must not be a temporary or leak-detecting allocator, since `std.os` /// retains ownership of allocations internally and may never call free(). pub fn initPreopensWasi(alloc: Allocator, cwd_root: []const u8) !void { if (builtin.os.tag == .wasi) { if (!builtin.link_libc) { var preopen_list = PreopenList.init(alloc); errdefer preopen_list.deinit(); try preopen_list.populate(cwd_root); var path_alloc = std.heap.FixedBufferAllocator.init(&wasi_cwd.path_buffer); wasi_cwd.cwd = try path_alloc.allocator().dupe(u8, cwd_root); if (wasi_cwd.preopens) |preopens| preopens.deinit(); wasi_cwd.preopens = preopen_list; } else { // wasi-libc defaults to an effective CWD root of "/" if (!mem.eql(u8, cwd_root, "/")) return error.UnsupportedDirectory; } } } /// Resolve a relative or absolute path to an handle (`fd_t`) and a relative subpath. /// /// For absolute paths, this automatically searches among available Preopens to find /// a match. For relative paths, it uses the "emulated" CWD. /// Automatically looks up the correct Preopen corresponding to the provided path. pub fn resolvePathWasi(path: []const u8, out_buffer: *[MAX_PATH_BYTES]u8) !RelativePathWasi { var allocator = std.heap.FixedBufferAllocator.init(out_buffer); var alloc = allocator.allocator(); const abs_path = fs.path.resolve(alloc, &.{ wasi_cwd.cwd, path }) catch return error.NameTooLong; const preopen_uri = wasi_cwd.preopens.?.findContaining(.{ .Dir = abs_path }); if (preopen_uri) |po| { return RelativePathWasi{ .dir_fd = po.base.fd, .relative_path = po.relative_path, }; } else { // No matching preopen found return error.AccessDenied; } } /// Open and possibly create a file. Keeps trying if it gets interrupted. /// `file_path` is relative to the open directory handle `dir_fd`. /// See also `openatZ`. pub fn openat(dir_fd: fd_t, file_path: []const u8, flags: u32, mode: mode_t) OpenError!fd_t { if (builtin.os.tag == .windows) { const file_path_w = try windows.sliceToPrefixedFileW(file_path); return openatW(dir_fd, file_path_w.span(), flags, mode); } else if (builtin.os.tag == .wasi and !builtin.link_libc) { // `mode` is ignored on WASI, which does not support unix-style file permissions const fd = if (dir_fd == wasi.AT.FDCWD or fs.path.isAbsolute(file_path)) blk: { // Resolve absolute or CWD-relative paths to a path within a Preopen var path_buf: [MAX_PATH_BYTES]u8 = undefined; const path = try resolvePathWasi(file_path, &path_buf); const opts = try openOptionsFromFlagsWasi(path.dir_fd, flags); break :blk try openatWasi(path.dir_fd, path.relative_path, opts.lookup_flags, opts.oflags, opts.fs_flags, opts.fs_rights_base, opts.fs_rights_inheriting); } else blk: { const opts = try openOptionsFromFlagsWasi(dir_fd, flags); break :blk try openatWasi(dir_fd, file_path, opts.lookup_flags, opts.oflags, opts.fs_flags, opts.fs_rights_base, opts.fs_rights_inheriting); }; errdefer close(fd); const info = try fstat(fd); if (flags & O.WRONLY != 0 and info.filetype == .DIRECTORY) return error.IsDir; return fd; } const file_path_c = try toPosixPath(file_path); return openatZ(dir_fd, &file_path_c, flags, mode); } /// A struct to contain all lookup/rights flags accepted by `wasi.path_open` const WasiOpenOptions = struct { oflags: wasi.oflags_t, lookup_flags: wasi.lookupflags_t, fs_rights_base: wasi.rights_t, fs_rights_inheriting: wasi.rights_t, fs_flags: wasi.fdflags_t, }; /// Compute rights + flags corresponding to the provided POSIX access mode. fn openOptionsFromFlagsWasi(fd: fd_t, oflag: u32) OpenError!WasiOpenOptions { const w = std.os.wasi; // First, discover the rights that we can derive from `fd` var fsb_cur: wasi.fdstat_t = undefined; _ = switch (w.fd_fdstat_get(fd, &fsb_cur)) { .SUCCESS => .{}, .BADF => return error.InvalidHandle, else => |err| return unexpectedErrno(err), }; // Next, calculate the read/write rights to request, depending on the // provided POSIX access mode var rights: w.rights_t = 0; if (oflag & O.RDONLY != 0) { rights |= w.RIGHT.FD_READ | w.RIGHT.FD_READDIR; } if (oflag & O.WRONLY != 0) { rights |= w.RIGHT.FD_DATASYNC | w.RIGHT.FD_WRITE | w.RIGHT.FD_ALLOCATE | w.RIGHT.FD_FILESTAT_SET_SIZE; } // Request all other rights unconditionally rights |= ~(w.RIGHT.FD_DATASYNC | w.RIGHT.FD_READ | w.RIGHT.FD_WRITE | w.RIGHT.FD_ALLOCATE | w.RIGHT.FD_READDIR | w.RIGHT.FD_FILESTAT_SET_SIZE); // But only take rights that we can actually inherit rights &= fsb_cur.fs_rights_inheriting; return WasiOpenOptions{ .oflags = @truncate(w.oflags_t, (oflag >> 12)) & 0xfff, .lookup_flags = if (oflag & O.NOFOLLOW == 0) w.LOOKUP_SYMLINK_FOLLOW else 0, .fs_rights_base = rights, .fs_rights_inheriting = fsb_cur.fs_rights_inheriting, .fs_flags = @truncate(w.fdflags_t, oflag & 0xfff), }; } /// Open and possibly create a file in WASI. pub fn openatWasi(dir_fd: fd_t, file_path: []const u8, lookup_flags: lookupflags_t, oflags: oflags_t, fdflags: fdflags_t, base: rights_t, inheriting: rights_t) OpenError!fd_t { while (true) { var fd: fd_t = undefined; switch (wasi.path_open(dir_fd, lookup_flags, file_path.ptr, file_path.len, oflags, base, inheriting, fdflags, &fd)) { .SUCCESS => return fd, .INTR => continue, .FAULT => unreachable, .INVAL => unreachable, .ACCES => return error.AccessDenied, .FBIG => return error.FileTooBig, .OVERFLOW => return error.FileTooBig, .ISDIR => return error.IsDir, .LOOP => return error.SymLinkLoop, .MFILE => return error.ProcessFdQuotaExceeded, .NAMETOOLONG => return error.NameTooLong, .NFILE => return error.SystemFdQuotaExceeded, .NODEV => return error.NoDevice, .NOENT => return error.FileNotFound, .NOMEM => return error.SystemResources, .NOSPC => return error.NoSpaceLeft, .NOTDIR => return error.NotDir, .PERM => return error.AccessDenied, .EXIST => return error.PathAlreadyExists, .BUSY => return error.DeviceBusy, .NOTCAPABLE => return error.AccessDenied, else => |err| return unexpectedErrno(err), } } } /// Open and possibly create a file. Keeps trying if it gets interrupted. /// `file_path` is relative to the open directory handle `dir_fd`. /// See also `openat`. pub fn openatZ(dir_fd: fd_t, file_path: [*:0]const u8, flags: u32, mode: mode_t) OpenError!fd_t { if (builtin.os.tag == .windows) { const file_path_w = try windows.cStrToPrefixedFileW(file_path); return openatW(dir_fd, file_path_w.span(), flags, mode); } else if (builtin.os.tag == .wasi and !builtin.link_libc) { return openat(dir_fd, mem.sliceTo(file_path, 0), flags, mode); } const openat_sym = if (builtin.os.tag == .linux and builtin.link_libc) system.openat64 else system.openat; while (true) { const rc = openat_sym(dir_fd, file_path, flags, mode); switch (errno(rc)) { .SUCCESS => return @intCast(fd_t, rc), .INTR => continue, .FAULT => unreachable, .INVAL => unreachable, .BADF => unreachable, .ACCES => return error.AccessDenied, .FBIG => return error.FileTooBig, .OVERFLOW => return error.FileTooBig, .ISDIR => return error.IsDir, .LOOP => return error.SymLinkLoop, .MFILE => return error.ProcessFdQuotaExceeded, .NAMETOOLONG => return error.NameTooLong, .NFILE => return error.SystemFdQuotaExceeded, .NODEV => return error.NoDevice, .NOENT => return error.FileNotFound, .NOMEM => return error.SystemResources, .NOSPC => return error.NoSpaceLeft, .NOTDIR => return error.NotDir, .PERM => return error.AccessDenied, .EXIST => return error.PathAlreadyExists, .BUSY => return error.DeviceBusy, .OPNOTSUPP => return error.FileLocksNotSupported, .AGAIN => return error.WouldBlock, .TXTBSY => return error.FileBusy, else => |err| return unexpectedErrno(err), } } } /// Windows-only. Similar to `openat` but with pathname argument null-terminated /// WTF16 encoded. /// TODO currently, this function does not handle all flag combinations /// or makes use of perm argument. pub fn openatW(dir_fd: fd_t, file_path_w: []const u16, flags: u32, mode: mode_t) OpenError!fd_t { _ = mode; var options = openOptionsFromFlagsWindows(flags); options.dir = dir_fd; return windows.OpenFile(file_path_w, options) catch |err| switch (err) { error.WouldBlock => unreachable, error.PipeBusy => unreachable, else => |e| return e, }; } pub fn dup(old_fd: fd_t) !fd_t { const rc = system.dup(old_fd); return switch (errno(rc)) { .SUCCESS => return @intCast(fd_t, rc), .MFILE => error.ProcessFdQuotaExceeded, .BADF => unreachable, // invalid file descriptor else => |err| return unexpectedErrno(err), }; } pub fn dup2(old_fd: fd_t, new_fd: fd_t) !void { while (true) { switch (errno(system.dup2(old_fd, new_fd))) { .SUCCESS => return, .BUSY, .INTR => continue, .MFILE => return error.ProcessFdQuotaExceeded, .INVAL => unreachable, // invalid parameters passed to dup2 .BADF => unreachable, // invalid file descriptor else => |err| return unexpectedErrno(err), } } } pub const ExecveError = error{ SystemResources, AccessDenied, InvalidExe, FileSystem, IsDir, FileNotFound, NotDir, FileBusy, ProcessFdQuotaExceeded, SystemFdQuotaExceeded, NameTooLong, } || UnexpectedError; /// This function ignores PATH environment variable. See `execvpeZ` for that. pub fn execveZ( path: [*:0]const u8, child_argv: [*:null]const ?[*:0]const u8, envp: [*:null]const ?[*:0]const u8, ) ExecveError { switch (errno(system.execve(path, child_argv, envp))) { .SUCCESS => unreachable, .FAULT => unreachable, .@"2BIG" => return error.SystemResources, .MFILE => return error.ProcessFdQuotaExceeded, .NAMETOOLONG => return error.NameTooLong, .NFILE => return error.SystemFdQuotaExceeded, .NOMEM => return error.SystemResources, .ACCES => return error.AccessDenied, .PERM => return error.AccessDenied, .INVAL => return error.InvalidExe, .NOEXEC => return error.InvalidExe, .IO => return error.FileSystem, .LOOP => return error.FileSystem, .ISDIR => return error.IsDir, .NOENT => return error.FileNotFound, .NOTDIR => return error.NotDir, .TXTBSY => return error.FileBusy, else => |err| switch (builtin.os.tag) { .macos, .ios, .tvos, .watchos => switch (err) { .BADEXEC => return error.InvalidExe, .BADARCH => return error.InvalidExe, else => return unexpectedErrno(err), }, .linux, .solaris => switch (err) { .LIBBAD => return error.InvalidExe, else => return unexpectedErrno(err), }, else => return unexpectedErrno(err), }, } } pub const Arg0Expand = enum { expand, no_expand, }; /// Like `execvpeZ` except if `arg0_expand` is `.expand`, then `argv` is mutable, /// and `argv[0]` is expanded to be the same absolute path that is passed to the execve syscall. /// If this function returns with an error, `argv[0]` will be restored to the value it was when it was passed in. pub fn execvpeZ_expandArg0( comptime arg0_expand: Arg0Expand, file: [*:0]const u8, child_argv: switch (arg0_expand) { .expand => [*:null]?[*:0]const u8, .no_expand => [*:null]const ?[*:0]const u8, }, envp: [*:null]const ?[*:0]const u8, ) ExecveError { const file_slice = mem.sliceTo(file, 0); if (mem.indexOfScalar(u8, file_slice, '/') != null) return execveZ(file, child_argv, envp); const PATH = getenvZ("PATH") orelse "/usr/local/bin:/bin/:/usr/bin"; // Use of MAX_PATH_BYTES here is valid as the path_buf will be passed // directly to the operating system in execveZ. var path_buf: [MAX_PATH_BYTES]u8 = undefined; var it = mem.tokenize(u8, PATH, ":"); var seen_eacces = false; var err: ExecveError = error.FileNotFound; // In case of expanding arg0 we must put it back if we return with an error. const prev_arg0 = child_argv[0]; defer switch (arg0_expand) { .expand => child_argv[0] = prev_arg0, .no_expand => {}, }; while (it.next()) |search_path| { const path_len = search_path.len + file_slice.len + 1; if (path_buf.len < path_len + 1) return error.NameTooLong; mem.copy(u8, &path_buf, search_path); path_buf[search_path.len] = '/'; mem.copy(u8, path_buf[search_path.len + 1 ..], file_slice); path_buf[path_len] = 0; const full_path = path_buf[0..path_len :0].ptr; switch (arg0_expand) { .expand => child_argv[0] = full_path, .no_expand => {}, } err = execveZ(full_path, child_argv, envp); switch (err) { error.AccessDenied => seen_eacces = true, error.FileNotFound, error.NotDir => {}, else => |e| return e, } } if (seen_eacces) return error.AccessDenied; return err; } /// This function also uses the PATH environment variable to get the full path to the executable. /// If `file` is an absolute path, this is the same as `execveZ`. pub fn execvpeZ( file: [*:0]const u8, argv_ptr: [*:null]const ?[*:0]const u8, envp: [*:null]const ?[*:0]const u8, ) ExecveError { return execvpeZ_expandArg0(.no_expand, file, argv_ptr, envp); } /// Get an environment variable. /// See also `getenvZ`. pub fn getenv(key: []const u8) ?[]const u8 { if (builtin.link_libc) { var small_key_buf: [64]u8 = undefined; if (key.len < small_key_buf.len) { mem.copy(u8, &small_key_buf, key); small_key_buf[key.len] = 0; const key0 = small_key_buf[0..key.len :0]; return getenvZ(key0); } // Search the entire `environ` because we don't have a null terminated pointer. var ptr = std.c.environ; while (ptr[0]) |line| : (ptr += 1) { var line_i: usize = 0; while (line[line_i] != 0 and line[line_i] != '=') : (line_i += 1) {} const this_key = line[0..line_i]; if (!mem.eql(u8, this_key, key)) continue; var end_i: usize = line_i; while (line[end_i] != 0) : (end_i += 1) {} const value = line[line_i + 1 .. end_i]; return value; } return null; } if (builtin.os.tag == .windows) { @compileError("std.os.getenv is unavailable for Windows because environment string is in WTF-16 format. See std.process.getEnvVarOwned for cross-platform API or std.os.getenvW for Windows-specific API."); } // TODO see https://github.com/ziglang/zig/issues/4524 for (environ) |ptr| { var line_i: usize = 0; while (ptr[line_i] != 0 and ptr[line_i] != '=') : (line_i += 1) {} const this_key = ptr[0..line_i]; if (!mem.eql(u8, key, this_key)) continue; var end_i: usize = line_i; while (ptr[end_i] != 0) : (end_i += 1) {} const this_value = ptr[line_i + 1 .. end_i]; return this_value; } return null; } /// Get an environment variable with a null-terminated name. /// See also `getenv`. pub fn getenvZ(key: [*:0]const u8) ?[]const u8 { if (builtin.link_libc) { const value = system.getenv(key) orelse return null; return mem.sliceTo(value, 0); } if (builtin.os.tag == .windows) { @compileError("std.os.getenvZ is unavailable for Windows because environment string is in WTF-16 format. See std.process.getEnvVarOwned for cross-platform API or std.os.getenvW for Windows-specific API."); } return getenv(mem.sliceTo(key, 0)); } /// Windows-only. Get an environment variable with a null-terminated, WTF-16 encoded name. /// See also `getenv`. /// This function performs a Unicode-aware case-insensitive lookup using RtlEqualUnicodeString. pub fn getenvW(key: [*:0]const u16) ?[:0]const u16 { if (builtin.os.tag != .windows) { @compileError("std.os.getenvW is a Windows-only API"); } const key_slice = mem.sliceTo(key, 0); const ptr = windows.peb().ProcessParameters.Environment; var i: usize = 0; while (ptr[i] != 0) { const key_start = i; // There are some special environment variables that start with =, // so we need a special case to not treat = as a key/value separator // if it's the first character. // https://devblogs.microsoft.com/oldnewthing/20100506-00/?p=14133 if (ptr[key_start] == '=') i += 1; while (ptr[i] != 0 and ptr[i] != '=') : (i += 1) {} const this_key = ptr[key_start..i]; if (ptr[i] == '=') i += 1; const value_start = i; while (ptr[i] != 0) : (i += 1) {} const this_value = ptr[value_start..i :0]; const key_string_bytes = @intCast(u16, key_slice.len * 2); const key_string = windows.UNICODE_STRING{ .Length = key_string_bytes, .MaximumLength = key_string_bytes, .Buffer = @intToPtr([*]u16, @ptrToInt(key)), }; const this_key_string_bytes = @intCast(u16, this_key.len * 2); const this_key_string = windows.UNICODE_STRING{ .Length = this_key_string_bytes, .MaximumLength = this_key_string_bytes, .Buffer = this_key.ptr, }; if (windows.ntdll.RtlEqualUnicodeString(&key_string, &this_key_string, windows.TRUE) == windows.TRUE) { return this_value; } i += 1; // skip over null byte } return null; } pub const GetCwdError = error{ NameTooLong, CurrentWorkingDirectoryUnlinked, } || UnexpectedError; /// The result is a slice of out_buffer, indexed from 0. pub fn getcwd(out_buffer: []u8) GetCwdError![]u8 { if (builtin.os.tag == .windows) { return windows.GetCurrentDirectory(out_buffer); } else if (builtin.os.tag == .wasi and !builtin.link_libc) { const path = wasi_cwd.cwd; if (out_buffer.len < path.len) return error.NameTooLong; std.mem.copy(u8, out_buffer, path); return out_buffer[0..path.len]; } const err = if (builtin.link_libc) blk: { const c_err = if (std.c.getcwd(out_buffer.ptr, out_buffer.len)) |_| 0 else std.c._errno().*; break :blk @intToEnum(E, c_err); } else blk: { break :blk errno(system.getcwd(out_buffer.ptr, out_buffer.len)); }; switch (err) { .SUCCESS => return mem.sliceTo(std.meta.assumeSentinel(out_buffer.ptr, 0), 0), .FAULT => unreachable, .INVAL => unreachable, .NOENT => return error.CurrentWorkingDirectoryUnlinked, .RANGE => return error.NameTooLong, else => return unexpectedErrno(err), } } pub const SymLinkError = error{ /// In WASI, this error may occur when the file descriptor does /// not hold the required rights to create a new symbolic link relative to it. AccessDenied, DiskQuota, PathAlreadyExists, FileSystem, SymLinkLoop, FileNotFound, SystemResources, NoSpaceLeft, ReadOnlyFileSystem, NotDir, NameTooLong, InvalidUtf8, BadPathName, } || UnexpectedError; /// Creates a symbolic link named `sym_link_path` which contains the string `target_path`. /// A symbolic link (also known as a soft link) may point to an existing file or to a nonexistent /// one; the latter case is known as a dangling link. /// If `sym_link_path` exists, it will not be overwritten. /// See also `symlinkZ. pub fn symlink(target_path: []const u8, sym_link_path: []const u8) SymLinkError!void { if (builtin.os.tag == .windows) { @compileError("symlink is not supported on Windows; use std.os.windows.CreateSymbolicLink instead"); } else if (builtin.os.tag == .wasi and !builtin.link_libc) { return symlinkat(target_path, wasi.AT.FDCWD, sym_link_path); } const target_path_c = try toPosixPath(target_path); const sym_link_path_c = try toPosixPath(sym_link_path); return symlinkZ(&target_path_c, &sym_link_path_c); } /// This is the same as `symlink` except the parameters are null-terminated pointers. /// See also `symlink`. pub fn symlinkZ(target_path: [*:0]const u8, sym_link_path: [*:0]const u8) SymLinkError!void { if (builtin.os.tag == .windows) { @compileError("symlink is not supported on Windows; use std.os.windows.CreateSymbolicLink instead"); } else if (builtin.os.tag == .wasi and !builtin.link_libc) { return symlink(mem.sliceTo(target_path, 0), mem.sliceTo(sym_link_path, 0)); } switch (errno(system.symlink(target_path, sym_link_path))) { .SUCCESS => return, .FAULT => unreachable, .INVAL => unreachable, .ACCES => return error.AccessDenied, .PERM => return error.AccessDenied, .DQUOT => return error.DiskQuota, .EXIST => return error.PathAlreadyExists, .IO => return error.FileSystem, .LOOP => return error.SymLinkLoop, .NAMETOOLONG => return error.NameTooLong, .NOENT => return error.FileNotFound, .NOTDIR => return error.NotDir, .NOMEM => return error.SystemResources, .NOSPC => return error.NoSpaceLeft, .ROFS => return error.ReadOnlyFileSystem, else => |err| return unexpectedErrno(err), } } /// Similar to `symlink`, however, creates a symbolic link named `sym_link_path` which contains the string /// `target_path` **relative** to `newdirfd` directory handle. /// A symbolic link (also known as a soft link) may point to an existing file or to a nonexistent /// one; the latter case is known as a dangling link. /// If `sym_link_path` exists, it will not be overwritten. /// See also `symlinkatWasi`, `symlinkatZ` and `symlinkatW`. pub fn symlinkat(target_path: []const u8, newdirfd: fd_t, sym_link_path: []const u8) SymLinkError!void { if (builtin.os.tag == .windows) { @compileError("symlinkat is not supported on Windows; use std.os.windows.CreateSymbolicLink instead"); } else if (builtin.os.tag == .wasi and !builtin.link_libc) { if (newdirfd == wasi.AT.FDCWD or fs.path.isAbsolute(target_path)) { // Resolve absolute or CWD-relative paths to a path within a Preopen var path_buf: [MAX_PATH_BYTES]u8 = undefined; const path = try resolvePathWasi(sym_link_path, &path_buf); return symlinkatWasi(target_path, path.dir_fd, path.relative_path); } return symlinkatWasi(target_path, newdirfd, sym_link_path); } const target_path_c = try toPosixPath(target_path); const sym_link_path_c = try toPosixPath(sym_link_path); return symlinkatZ(&target_path_c, newdirfd, &sym_link_path_c); } /// WASI-only. The same as `symlinkat` but targeting WASI. /// See also `symlinkat`. pub fn symlinkatWasi(target_path: []const u8, newdirfd: fd_t, sym_link_path: []const u8) SymLinkError!void { switch (wasi.path_symlink(target_path.ptr, target_path.len, newdirfd, sym_link_path.ptr, sym_link_path.len)) { .SUCCESS => {}, .FAULT => unreachable, .INVAL => unreachable, .ACCES => return error.AccessDenied, .PERM => return error.AccessDenied, .DQUOT => return error.DiskQuota, .EXIST => return error.PathAlreadyExists, .IO => return error.FileSystem, .LOOP => return error.SymLinkLoop, .NAMETOOLONG => return error.NameTooLong, .NOENT => return error.FileNotFound, .NOTDIR => return error.NotDir, .NOMEM => return error.SystemResources, .NOSPC => return error.NoSpaceLeft, .ROFS => return error.ReadOnlyFileSystem, .NOTCAPABLE => return error.AccessDenied, else => |err| return unexpectedErrno(err), } } /// The same as `symlinkat` except the parameters are null-terminated pointers. /// See also `symlinkat`. pub fn symlinkatZ(target_path: [*:0]const u8, newdirfd: fd_t, sym_link_path: [*:0]const u8) SymLinkError!void { if (builtin.os.tag == .windows) { @compileError("symlinkat is not supported on Windows; use std.os.windows.CreateSymbolicLink instead"); } else if (builtin.os.tag == .wasi and !builtin.link_libc) { return symlinkat(mem.sliceTo(target_path, 0), newdirfd, mem.sliceTo(sym_link_path, 0)); } switch (errno(system.symlinkat(target_path, newdirfd, sym_link_path))) { .SUCCESS => return, .FAULT => unreachable, .INVAL => unreachable, .ACCES => return error.AccessDenied, .PERM => return error.AccessDenied, .DQUOT => return error.DiskQuota, .EXIST => return error.PathAlreadyExists, .IO => return error.FileSystem, .LOOP => return error.SymLinkLoop, .NAMETOOLONG => return error.NameTooLong, .NOENT => return error.FileNotFound, .NOTDIR => return error.NotDir, .NOMEM => return error.SystemResources, .NOSPC => return error.NoSpaceLeft, .ROFS => return error.ReadOnlyFileSystem, else => |err| return unexpectedErrno(err), } } pub const LinkError = UnexpectedError || error{ AccessDenied, DiskQuota, PathAlreadyExists, FileSystem, SymLinkLoop, LinkQuotaExceeded, NameTooLong, FileNotFound, SystemResources, NoSpaceLeft, ReadOnlyFileSystem, NotSameFileSystem, }; pub fn linkZ(oldpath: [*:0]const u8, newpath: [*:0]const u8, flags: i32) LinkError!void { if (builtin.os.tag == .wasi and !builtin.link_libc) { return link(mem.sliceTo(oldpath, 0), mem.sliceTo(newpath, 0), flags); } switch (errno(system.link(oldpath, newpath, flags))) { .SUCCESS => return, .ACCES => return error.AccessDenied, .DQUOT => return error.DiskQuota, .EXIST => return error.PathAlreadyExists, .FAULT => unreachable, .IO => return error.FileSystem, .LOOP => return error.SymLinkLoop, .MLINK => return error.LinkQuotaExceeded, .NAMETOOLONG => return error.NameTooLong, .NOENT => return error.FileNotFound, .NOMEM => return error.SystemResources, .NOSPC => return error.NoSpaceLeft, .PERM => return error.AccessDenied, .ROFS => return error.ReadOnlyFileSystem, .XDEV => return error.NotSameFileSystem, .INVAL => unreachable, else => |err| return unexpectedErrno(err), } } pub fn link(oldpath: []const u8, newpath: []const u8, flags: i32) LinkError!void { if (builtin.os.tag == .wasi and !builtin.link_libc) { return linkat(wasi.AT.FDCWD, oldpath, wasi.AT.FDCWD, newpath, flags) catch |err| switch (err) { error.NotDir => unreachable, // link() does not support directories else => |e| return e, }; } const old = try toPosixPath(oldpath); const new = try toPosixPath(newpath); return try linkZ(&old, &new, flags); } pub const LinkatError = LinkError || error{NotDir}; pub fn linkatZ( olddir: fd_t, oldpath: [*:0]const u8, newdir: fd_t, newpath: [*:0]const u8, flags: i32, ) LinkatError!void { if (builtin.os.tag == .wasi and !builtin.link_libc) { return linkat(olddir, mem.sliceTo(oldpath, 0), newdir, mem.sliceTo(newpath, 0), flags); } switch (errno(system.linkat(olddir, oldpath, newdir, newpath, flags))) { .SUCCESS => return, .ACCES => return error.AccessDenied, .DQUOT => return error.DiskQuota, .EXIST => return error.PathAlreadyExists, .FAULT => unreachable, .IO => return error.FileSystem, .LOOP => return error.SymLinkLoop, .MLINK => return error.LinkQuotaExceeded, .NAMETOOLONG => return error.NameTooLong, .NOENT => return error.FileNotFound, .NOMEM => return error.SystemResources, .NOSPC => return error.NoSpaceLeft, .NOTDIR => return error.NotDir, .PERM => return error.AccessDenied, .ROFS => return error.ReadOnlyFileSystem, .XDEV => return error.NotSameFileSystem, .INVAL => unreachable, else => |err| return unexpectedErrno(err), } } pub fn linkat( olddir: fd_t, oldpath: []const u8, newdir: fd_t, newpath: []const u8, flags: i32, ) LinkatError!void { if (builtin.os.tag == .wasi and !builtin.link_libc) { var resolve_olddir: bool = (olddir == wasi.AT.FDCWD or fs.path.isAbsolute(oldpath)); var resolve_newdir: bool = (newdir == wasi.AT.FDCWD or fs.path.isAbsolute(newpath)); var old: RelativePathWasi = .{ .dir_fd = olddir, .relative_path = oldpath }; var new: RelativePathWasi = .{ .dir_fd = newdir, .relative_path = newpath }; // Resolve absolute or CWD-relative paths to a path within a Preopen if (resolve_olddir or resolve_newdir) { var buf_old: [MAX_PATH_BYTES]u8 = undefined; var buf_new: [MAX_PATH_BYTES]u8 = undefined; if (resolve_olddir) old = try resolvePathWasi(oldpath, &buf_old); if (resolve_newdir) new = try resolvePathWasi(newpath, &buf_new); return linkatWasi(old, new, flags); } return linkatWasi(old, new, flags); } const old = try toPosixPath(oldpath); const new = try toPosixPath(newpath); return try linkatZ(olddir, &old, newdir, &new, flags); } /// WASI-only. The same as `linkat` but targeting WASI. /// See also `linkat`. pub fn linkatWasi(old: RelativePathWasi, new: RelativePathWasi, flags: i32) LinkatError!void { var old_flags: wasi.lookupflags_t = 0; // TODO: Why is this not defined in wasi-libc? if (flags & linux.AT.SYMLINK_FOLLOW != 0) old_flags |= wasi.LOOKUP_SYMLINK_FOLLOW; switch (wasi.path_link(old.dir_fd, old_flags, old.relative_path.ptr, old.relative_path.len, new.dir_fd, new.relative_path.ptr, new.relative_path.len)) { .SUCCESS => return, .ACCES => return error.AccessDenied, .DQUOT => return error.DiskQuota, .EXIST => return error.PathAlreadyExists, .FAULT => unreachable, .IO => return error.FileSystem, .LOOP => return error.SymLinkLoop, .MLINK => return error.LinkQuotaExceeded, .NAMETOOLONG => return error.NameTooLong, .NOENT => return error.FileNotFound, .NOMEM => return error.SystemResources, .NOSPC => return error.NoSpaceLeft, .NOTDIR => return error.NotDir, .PERM => return error.AccessDenied, .ROFS => return error.ReadOnlyFileSystem, .XDEV => return error.NotSameFileSystem, .INVAL => unreachable, else => |err| return unexpectedErrno(err), } } pub const UnlinkError = error{ FileNotFound, /// In WASI, this error may occur when the file descriptor does /// not hold the required rights to unlink a resource by path relative to it. AccessDenied, FileBusy, FileSystem, IsDir, SymLinkLoop, NameTooLong, NotDir, SystemResources, ReadOnlyFileSystem, /// On Windows, file paths must be valid Unicode. InvalidUtf8, /// On Windows, file paths cannot contain these characters: /// '/', '*', '?', '"', '<', '>', '|' BadPathName, } || UnexpectedError; /// Delete a name and possibly the file it refers to. /// See also `unlinkZ`. pub fn unlink(file_path: []const u8) UnlinkError!void { if (builtin.os.tag == .wasi and !builtin.link_libc) { return unlinkat(wasi.AT.FDCWD, file_path, 0) catch |err| switch (err) { error.DirNotEmpty => unreachable, // only occurs when targeting directories else => |e| return e, }; } else if (builtin.os.tag == .windows) { const file_path_w = try windows.sliceToPrefixedFileW(file_path); return unlinkW(file_path_w.span()); } else { const file_path_c = try toPosixPath(file_path); return unlinkZ(&file_path_c); } } /// Same as `unlink` except the parameter is a null terminated UTF8-encoded string. pub fn unlinkZ(file_path: [*:0]const u8) UnlinkError!void { if (builtin.os.tag == .windows) { const file_path_w = try windows.cStrToPrefixedFileW(file_path); return unlinkW(file_path_w.span()); } else if (builtin.os.tag == .wasi and !builtin.link_libc) { return unlink(mem.sliceTo(file_path, 0)); } switch (errno(system.unlink(file_path))) { .SUCCESS => return, .ACCES => return error.AccessDenied, .PERM => return error.AccessDenied, .BUSY => return error.FileBusy, .FAULT => unreachable, .INVAL => unreachable, .IO => return error.FileSystem, .ISDIR => return error.IsDir, .LOOP => return error.SymLinkLoop, .NAMETOOLONG => return error.NameTooLong, .NOENT => return error.FileNotFound, .NOTDIR => return error.NotDir, .NOMEM => return error.SystemResources, .ROFS => return error.ReadOnlyFileSystem, else => |err| return unexpectedErrno(err), } } /// Windows-only. Same as `unlink` except the parameter is null-terminated, WTF16 encoded. pub fn unlinkW(file_path_w: []const u16) UnlinkError!void { return windows.DeleteFile(file_path_w, .{ .dir = std.fs.cwd().fd }); } pub const UnlinkatError = UnlinkError || error{ /// When passing `AT.REMOVEDIR`, this error occurs when the named directory is not empty. DirNotEmpty, }; /// Delete a file name and possibly the file it refers to, based on an open directory handle. /// Asserts that the path parameter has no null bytes. pub fn unlinkat(dirfd: fd_t, file_path: []const u8, flags: u32) UnlinkatError!void { if (builtin.os.tag == .windows) { const file_path_w = try windows.sliceToPrefixedFileW(file_path); return unlinkatW(dirfd, file_path_w.span(), flags); } else if (builtin.os.tag == .wasi and !builtin.link_libc) { if (dirfd == wasi.AT.FDCWD or fs.path.isAbsolute(file_path)) { // Resolve absolute or CWD-relative paths to a path within a Preopen var path_buf: [MAX_PATH_BYTES]u8 = undefined; const path = try resolvePathWasi(file_path, &path_buf); return unlinkatWasi(path.dir_fd, path.relative_path, flags); } return unlinkatWasi(dirfd, file_path, flags); } else { const file_path_c = try toPosixPath(file_path); return unlinkatZ(dirfd, &file_path_c, flags); } } /// WASI-only. Same as `unlinkat` but targeting WASI. /// See also `unlinkat`. pub fn unlinkatWasi(dirfd: fd_t, file_path: []const u8, flags: u32) UnlinkatError!void { const remove_dir = (flags & AT.REMOVEDIR) != 0; const res = if (remove_dir) wasi.path_remove_directory(dirfd, file_path.ptr, file_path.len) else wasi.path_unlink_file(dirfd, file_path.ptr, file_path.len); switch (res) { .SUCCESS => return, .ACCES => return error.AccessDenied, .PERM => return error.AccessDenied, .BUSY => return error.FileBusy, .FAULT => unreachable, .IO => return error.FileSystem, .ISDIR => return error.IsDir, .LOOP => return error.SymLinkLoop, .NAMETOOLONG => return error.NameTooLong, .NOENT => return error.FileNotFound, .NOTDIR => return error.NotDir, .NOMEM => return error.SystemResources, .ROFS => return error.ReadOnlyFileSystem, .NOTEMPTY => return error.DirNotEmpty, .NOTCAPABLE => return error.AccessDenied, .INVAL => unreachable, // invalid flags, or pathname has . as last component .BADF => unreachable, // always a race condition else => |err| return unexpectedErrno(err), } } /// Same as `unlinkat` but `file_path` is a null-terminated string. pub fn unlinkatZ(dirfd: fd_t, file_path_c: [*:0]const u8, flags: u32) UnlinkatError!void { if (builtin.os.tag == .windows) { const file_path_w = try windows.cStrToPrefixedFileW(file_path_c); return unlinkatW(dirfd, file_path_w.span(), flags); } else if (builtin.os.tag == .wasi and !builtin.link_libc) { return unlinkat(dirfd, mem.sliceTo(file_path_c, 0), flags); } switch (errno(system.unlinkat(dirfd, file_path_c, flags))) { .SUCCESS => return, .ACCES => return error.AccessDenied, .PERM => return error.AccessDenied, .BUSY => return error.FileBusy, .FAULT => unreachable, .IO => return error.FileSystem, .ISDIR => return error.IsDir, .LOOP => return error.SymLinkLoop, .NAMETOOLONG => return error.NameTooLong, .NOENT => return error.FileNotFound, .NOTDIR => return error.NotDir, .NOMEM => return error.SystemResources, .ROFS => return error.ReadOnlyFileSystem, .EXIST => return error.DirNotEmpty, .NOTEMPTY => return error.DirNotEmpty, .INVAL => unreachable, // invalid flags, or pathname has . as last component .BADF => unreachable, // always a race condition else => |err| return unexpectedErrno(err), } } /// Same as `unlinkat` but `sub_path_w` is UTF16LE, NT prefixed. Windows only. pub fn unlinkatW(dirfd: fd_t, sub_path_w: []const u16, flags: u32) UnlinkatError!void { const remove_dir = (flags & AT.REMOVEDIR) != 0; return windows.DeleteFile(sub_path_w, .{ .dir = dirfd, .remove_dir = remove_dir }); } pub const RenameError = error{ /// In WASI, this error may occur when the file descriptor does /// not hold the required rights to rename a resource by path relative to it. AccessDenied, FileBusy, DiskQuota, IsDir, SymLinkLoop, LinkQuotaExceeded, NameTooLong, FileNotFound, NotDir, SystemResources, NoSpaceLeft, PathAlreadyExists, ReadOnlyFileSystem, RenameAcrossMountPoints, InvalidUtf8, BadPathName, NoDevice, SharingViolation, PipeBusy, } || UnexpectedError; /// Change the name or location of a file. pub fn rename(old_path: []const u8, new_path: []const u8) RenameError!void { if (builtin.os.tag == .wasi and !builtin.link_libc) { return renameat(wasi.AT.FDCWD, old_path, wasi.AT.FDCWD, new_path); } else if (builtin.os.tag == .windows) { const old_path_w = try windows.sliceToPrefixedFileW(old_path); const new_path_w = try windows.sliceToPrefixedFileW(new_path); return renameW(old_path_w.span().ptr, new_path_w.span().ptr); } else { const old_path_c = try toPosixPath(old_path); const new_path_c = try toPosixPath(new_path); return renameZ(&old_path_c, &new_path_c); } } /// Same as `rename` except the parameters are null-terminated byte arrays. pub fn renameZ(old_path: [*:0]const u8, new_path: [*:0]const u8) RenameError!void { if (builtin.os.tag == .windows) { const old_path_w = try windows.cStrToPrefixedFileW(old_path); const new_path_w = try windows.cStrToPrefixedFileW(new_path); return renameW(old_path_w.span().ptr, new_path_w.span().ptr); } else if (builtin.os.tag == .wasi and !builtin.link_libc) { return rename(mem.sliceTo(old_path, 0), mem.sliceTo(new_path, 0)); } switch (errno(system.rename(old_path, new_path))) { .SUCCESS => return, .ACCES => return error.AccessDenied, .PERM => return error.AccessDenied, .BUSY => return error.FileBusy, .DQUOT => return error.DiskQuota, .FAULT => unreachable, .INVAL => unreachable, .ISDIR => return error.IsDir, .LOOP => return error.SymLinkLoop, .MLINK => return error.LinkQuotaExceeded, .NAMETOOLONG => return error.NameTooLong, .NOENT => return error.FileNotFound, .NOTDIR => return error.NotDir, .NOMEM => return error.SystemResources, .NOSPC => return error.NoSpaceLeft, .EXIST => return error.PathAlreadyExists, .NOTEMPTY => return error.PathAlreadyExists, .ROFS => return error.ReadOnlyFileSystem, .XDEV => return error.RenameAcrossMountPoints, else => |err| return unexpectedErrno(err), } } /// Same as `rename` except the parameters are null-terminated UTF16LE encoded byte arrays. /// Assumes target is Windows. pub fn renameW(old_path: [*:0]const u16, new_path: [*:0]const u16) RenameError!void { const flags = windows.MOVEFILE_REPLACE_EXISTING | windows.MOVEFILE_WRITE_THROUGH; return windows.MoveFileExW(old_path, new_path, flags); } /// Change the name or location of a file based on an open directory handle. pub fn renameat( old_dir_fd: fd_t, old_path: []const u8, new_dir_fd: fd_t, new_path: []const u8, ) RenameError!void { if (builtin.os.tag == .windows) { const old_path_w = try windows.sliceToPrefixedFileW(old_path); const new_path_w = try windows.sliceToPrefixedFileW(new_path); return renameatW(old_dir_fd, old_path_w.span(), new_dir_fd, new_path_w.span(), windows.TRUE); } else if (builtin.os.tag == .wasi and !builtin.link_libc) { var resolve_old: bool = (old_dir_fd == wasi.AT.FDCWD or fs.path.isAbsolute(old_path)); var resolve_new: bool = (new_dir_fd == wasi.AT.FDCWD or fs.path.isAbsolute(new_path)); var old: RelativePathWasi = .{ .dir_fd = old_dir_fd, .relative_path = old_path }; var new: RelativePathWasi = .{ .dir_fd = new_dir_fd, .relative_path = new_path }; // Resolve absolute or CWD-relative paths to a path within a Preopen if (resolve_old or resolve_new) { var buf_old: [MAX_PATH_BYTES]u8 = undefined; var buf_new: [MAX_PATH_BYTES]u8 = undefined; if (resolve_old) old = try resolvePathWasi(old_path, &buf_old); if (resolve_new) new = try resolvePathWasi(new_path, &buf_new); return renameatWasi(old, new); } return renameatWasi(old, new); } else { const old_path_c = try toPosixPath(old_path); const new_path_c = try toPosixPath(new_path); return renameatZ(old_dir_fd, &old_path_c, new_dir_fd, &new_path_c); } } /// WASI-only. Same as `renameat` expect targeting WASI. /// See also `renameat`. pub fn renameatWasi(old: RelativePathWasi, new: RelativePathWasi) RenameError!void { switch (wasi.path_rename(old.dir_fd, old.relative_path.ptr, old.relative_path.len, new.dir_fd, new.relative_path.ptr, new.relative_path.len)) { .SUCCESS => return, .ACCES => return error.AccessDenied, .PERM => return error.AccessDenied, .BUSY => return error.FileBusy, .DQUOT => return error.DiskQuota, .FAULT => unreachable, .INVAL => unreachable, .ISDIR => return error.IsDir, .LOOP => return error.SymLinkLoop, .MLINK => return error.LinkQuotaExceeded, .NAMETOOLONG => return error.NameTooLong, .NOENT => return error.FileNotFound, .NOTDIR => return error.NotDir, .NOMEM => return error.SystemResources, .NOSPC => return error.NoSpaceLeft, .EXIST => return error.PathAlreadyExists, .NOTEMPTY => return error.PathAlreadyExists, .ROFS => return error.ReadOnlyFileSystem, .XDEV => return error.RenameAcrossMountPoints, .NOTCAPABLE => return error.AccessDenied, else => |err| return unexpectedErrno(err), } } /// Same as `renameat` except the parameters are null-terminated byte arrays. pub fn renameatZ( old_dir_fd: fd_t, old_path: [*:0]const u8, new_dir_fd: fd_t, new_path: [*:0]const u8, ) RenameError!void { if (builtin.os.tag == .windows) { const old_path_w = try windows.cStrToPrefixedFileW(old_path); const new_path_w = try windows.cStrToPrefixedFileW(new_path); return renameatW(old_dir_fd, old_path_w.span(), new_dir_fd, new_path_w.span(), windows.TRUE); } else if (builtin.os.tag == .wasi and !builtin.link_libc) { return renameat(old_dir_fd, mem.sliceTo(old_path, 0), new_dir_fd, mem.sliceTo(new_path, 0)); } switch (errno(system.renameat(old_dir_fd, old_path, new_dir_fd, new_path))) { .SUCCESS => return, .ACCES => return error.AccessDenied, .PERM => return error.AccessDenied, .BUSY => return error.FileBusy, .DQUOT => return error.DiskQuota, .FAULT => unreachable, .INVAL => unreachable, .ISDIR => return error.IsDir, .LOOP => return error.SymLinkLoop, .MLINK => return error.LinkQuotaExceeded, .NAMETOOLONG => return error.NameTooLong, .NOENT => return error.FileNotFound, .NOTDIR => return error.NotDir, .NOMEM => return error.SystemResources, .NOSPC => return error.NoSpaceLeft, .EXIST => return error.PathAlreadyExists, .NOTEMPTY => return error.PathAlreadyExists, .ROFS => return error.ReadOnlyFileSystem, .XDEV => return error.RenameAcrossMountPoints, else => |err| return unexpectedErrno(err), } } /// Same as `renameat` but Windows-only and the path parameters are /// [WTF-16](https://simonsapin.github.io/wtf-8/#potentially-ill-formed-utf-16) encoded. pub fn renameatW( old_dir_fd: fd_t, old_path_w: []const u16, new_dir_fd: fd_t, new_path_w: []const u16, ReplaceIfExists: windows.BOOLEAN, ) RenameError!void { const src_fd = windows.OpenFile(old_path_w, .{ .dir = old_dir_fd, .access_mask = windows.SYNCHRONIZE | windows.GENERIC_WRITE | windows.DELETE, .creation = windows.FILE_OPEN, .io_mode = .blocking, .filter = .any, // This function is supposed to rename both files and directories. .follow_symlinks = false, }) catch |err| switch (err) { error.WouldBlock => unreachable, // Not possible without `.share_access_nonblocking = true`. else => |e| return e, }; defer windows.CloseHandle(src_fd); const struct_buf_len = @sizeOf(windows.FILE_RENAME_INFORMATION) + (MAX_PATH_BYTES - 1); var rename_info_buf: [struct_buf_len]u8 align(@alignOf(windows.FILE_RENAME_INFORMATION)) = undefined; const struct_len = @sizeOf(windows.FILE_RENAME_INFORMATION) - 1 + new_path_w.len * 2; if (struct_len > struct_buf_len) return error.NameTooLong; const rename_info = @ptrCast(*windows.FILE_RENAME_INFORMATION, &rename_info_buf); rename_info.* = .{ .ReplaceIfExists = ReplaceIfExists, .RootDirectory = if (std.fs.path.isAbsoluteWindowsWTF16(new_path_w)) null else new_dir_fd, .FileNameLength = @intCast(u32, new_path_w.len * 2), // already checked error.NameTooLong .FileName = undefined, }; std.mem.copy(u16, @as([*]u16, &rename_info.FileName)[0..new_path_w.len], new_path_w); var io_status_block: windows.IO_STATUS_BLOCK = undefined; const rc = windows.ntdll.NtSetInformationFile( src_fd, &io_status_block, rename_info, @intCast(u32, struct_len), // already checked for error.NameTooLong .FileRenameInformation, ); switch (rc) { .SUCCESS => return, .INVALID_HANDLE => unreachable, .INVALID_PARAMETER => unreachable, .OBJECT_PATH_SYNTAX_BAD => unreachable, .ACCESS_DENIED => return error.AccessDenied, .OBJECT_NAME_NOT_FOUND => return error.FileNotFound, .OBJECT_PATH_NOT_FOUND => return error.FileNotFound, .NOT_SAME_DEVICE => return error.RenameAcrossMountPoints, else => return windows.unexpectedStatus(rc), } } pub fn mkdirat(dir_fd: fd_t, sub_dir_path: []const u8, mode: u32) MakeDirError!void { if (builtin.os.tag == .windows) { const sub_dir_path_w = try windows.sliceToPrefixedFileW(sub_dir_path); return mkdiratW(dir_fd, sub_dir_path_w.span(), mode); } else if (builtin.os.tag == .wasi and !builtin.link_libc) { if (dir_fd == wasi.AT.FDCWD or fs.path.isAbsolute(sub_dir_path)) { // Resolve absolute or CWD-relative paths to a path within a Preopen var path_buf: [MAX_PATH_BYTES]u8 = undefined; const path = try resolvePathWasi(sub_dir_path, &path_buf); return mkdiratWasi(path.dir_fd, path.relative_path, mode); } return mkdiratWasi(dir_fd, sub_dir_path, mode); } else { const sub_dir_path_c = try toPosixPath(sub_dir_path); return mkdiratZ(dir_fd, &sub_dir_path_c, mode); } } pub fn mkdiratWasi(dir_fd: fd_t, sub_dir_path: []const u8, mode: u32) MakeDirError!void { _ = mode; switch (wasi.path_create_directory(dir_fd, sub_dir_path.ptr, sub_dir_path.len)) { .SUCCESS => return, .ACCES => return error.AccessDenied, .BADF => unreachable, .PERM => return error.AccessDenied, .DQUOT => return error.DiskQuota, .EXIST => return error.PathAlreadyExists, .FAULT => unreachable, .LOOP => return error.SymLinkLoop, .MLINK => return error.LinkQuotaExceeded, .NAMETOOLONG => return error.NameTooLong, .NOENT => return error.FileNotFound, .NOMEM => return error.SystemResources, .NOSPC => return error.NoSpaceLeft, .NOTDIR => return error.NotDir, .ROFS => return error.ReadOnlyFileSystem, .NOTCAPABLE => return error.AccessDenied, else => |err| return unexpectedErrno(err), } } pub fn mkdiratZ(dir_fd: fd_t, sub_dir_path: [*:0]const u8, mode: u32) MakeDirError!void { if (builtin.os.tag == .windows) { const sub_dir_path_w = try windows.cStrToPrefixedFileW(sub_dir_path); return mkdiratW(dir_fd, sub_dir_path_w.span().ptr, mode); } else if (builtin.os.tag == .wasi and !builtin.link_libc) { return mkdirat(dir_fd, mem.sliceTo(sub_dir_path, 0), mode); } switch (errno(system.mkdirat(dir_fd, sub_dir_path, mode))) { .SUCCESS => return, .ACCES => return error.AccessDenied, .BADF => unreachable, .PERM => return error.AccessDenied, .DQUOT => return error.DiskQuota, .EXIST => return error.PathAlreadyExists, .FAULT => unreachable, .LOOP => return error.SymLinkLoop, .MLINK => return error.LinkQuotaExceeded, .NAMETOOLONG => return error.NameTooLong, .NOENT => return error.FileNotFound, .NOMEM => return error.SystemResources, .NOSPC => return error.NoSpaceLeft, .NOTDIR => return error.NotDir, .ROFS => return error.ReadOnlyFileSystem, else => |err| return unexpectedErrno(err), } } pub fn mkdiratW(dir_fd: fd_t, sub_path_w: []const u16, mode: u32) MakeDirError!void { _ = mode; const sub_dir_handle = windows.OpenFile(sub_path_w, .{ .dir = dir_fd, .access_mask = windows.GENERIC_READ | windows.SYNCHRONIZE, .creation = windows.FILE_CREATE, .io_mode = .blocking, .filter = .dir_only, }) catch |err| switch (err) { error.IsDir => unreachable, error.PipeBusy => unreachable, error.WouldBlock => unreachable, else => |e| return e, }; windows.CloseHandle(sub_dir_handle); } pub const MakeDirError = error{ /// In WASI, this error may occur when the file descriptor does /// not hold the required rights to create a new directory relative to it. AccessDenied, DiskQuota, PathAlreadyExists, SymLinkLoop, LinkQuotaExceeded, NameTooLong, FileNotFound, SystemResources, NoSpaceLeft, NotDir, ReadOnlyFileSystem, InvalidUtf8, BadPathName, NoDevice, } || UnexpectedError; /// Create a directory. /// `mode` is ignored on Windows and WASI. pub fn mkdir(dir_path: []const u8, mode: u32) MakeDirError!void { if (builtin.os.tag == .wasi and !builtin.link_libc) { return mkdirat(wasi.AT.FDCWD, dir_path, mode); } else if (builtin.os.tag == .windows) { const dir_path_w = try windows.sliceToPrefixedFileW(dir_path); return mkdirW(dir_path_w.span(), mode); } else { const dir_path_c = try toPosixPath(dir_path); return mkdirZ(&dir_path_c, mode); } } /// Same as `mkdir` but the parameter is a null-terminated UTF8-encoded string. pub fn mkdirZ(dir_path: [*:0]const u8, mode: u32) MakeDirError!void { if (builtin.os.tag == .windows) { const dir_path_w = try windows.cStrToPrefixedFileW(dir_path); return mkdirW(dir_path_w.span(), mode); } else if (builtin.os.tag == .wasi and !builtin.link_libc) { return mkdir(mem.sliceTo(dir_path, 0), mode); } switch (errno(system.mkdir(dir_path, mode))) { .SUCCESS => return, .ACCES => return error.AccessDenied, .PERM => return error.AccessDenied, .DQUOT => return error.DiskQuota, .EXIST => return error.PathAlreadyExists, .FAULT => unreachable, .LOOP => return error.SymLinkLoop, .MLINK => return error.LinkQuotaExceeded, .NAMETOOLONG => return error.NameTooLong, .NOENT => return error.FileNotFound, .NOMEM => return error.SystemResources, .NOSPC => return error.NoSpaceLeft, .NOTDIR => return error.NotDir, .ROFS => return error.ReadOnlyFileSystem, else => |err| return unexpectedErrno(err), } } /// Windows-only. Same as `mkdir` but the parameters is WTF16 encoded. pub fn mkdirW(dir_path_w: []const u16, mode: u32) MakeDirError!void { _ = mode; const sub_dir_handle = windows.OpenFile(dir_path_w, .{ .dir = std.fs.cwd().fd, .access_mask = windows.GENERIC_READ | windows.SYNCHRONIZE, .creation = windows.FILE_CREATE, .io_mode = .blocking, .filter = .dir_only, }) catch |err| switch (err) { error.IsDir => unreachable, error.PipeBusy => unreachable, error.WouldBlock => unreachable, else => |e| return e, }; windows.CloseHandle(sub_dir_handle); } pub const DeleteDirError = error{ AccessDenied, FileBusy, SymLinkLoop, NameTooLong, FileNotFound, SystemResources, NotDir, DirNotEmpty, ReadOnlyFileSystem, InvalidUtf8, BadPathName, } || UnexpectedError; /// Deletes an empty directory. pub fn rmdir(dir_path: []const u8) DeleteDirError!void { if (builtin.os.tag == .wasi and !builtin.link_libc) { return unlinkat(wasi.AT.FDCWD, dir_path, AT.REMOVEDIR) catch |err| switch (err) { error.FileSystem => unreachable, // only occurs when targeting files error.IsDir => unreachable, // only occurs when targeting files else => |e| return e, }; } else if (builtin.os.tag == .windows) { const dir_path_w = try windows.sliceToPrefixedFileW(dir_path); return rmdirW(dir_path_w.span()); } else { const dir_path_c = try toPosixPath(dir_path); return rmdirZ(&dir_path_c); } } /// Same as `rmdir` except the parameter is null-terminated. pub fn rmdirZ(dir_path: [*:0]const u8) DeleteDirError!void { if (builtin.os.tag == .windows) { const dir_path_w = try windows.cStrToPrefixedFileW(dir_path); return rmdirW(dir_path_w.span()); } else if (builtin.os.tag == .wasi and !builtin.link_libc) { return rmdir(mem.sliceTo(dir_path, 0)); } switch (errno(system.rmdir(dir_path))) { .SUCCESS => return, .ACCES => return error.AccessDenied, .PERM => return error.AccessDenied, .BUSY => return error.FileBusy, .FAULT => unreachable, .INVAL => return error.BadPathName, .LOOP => return error.SymLinkLoop, .NAMETOOLONG => return error.NameTooLong, .NOENT => return error.FileNotFound, .NOMEM => return error.SystemResources, .NOTDIR => return error.NotDir, .EXIST => return error.DirNotEmpty, .NOTEMPTY => return error.DirNotEmpty, .ROFS => return error.ReadOnlyFileSystem, else => |err| return unexpectedErrno(err), } } /// Windows-only. Same as `rmdir` except the parameter is WTF16 encoded. pub fn rmdirW(dir_path_w: []const u16) DeleteDirError!void { return windows.DeleteFile(dir_path_w, .{ .dir = std.fs.cwd().fd, .remove_dir = true }) catch |err| switch (err) { error.IsDir => unreachable, else => |e| return e, }; } pub const ChangeCurDirError = error{ AccessDenied, FileSystem, SymLinkLoop, NameTooLong, FileNotFound, SystemResources, NotDir, BadPathName, /// On Windows, file paths must be valid Unicode. InvalidUtf8, } || UnexpectedError; /// Changes the current working directory of the calling process. /// `dir_path` is recommended to be a UTF-8 encoded string. pub fn chdir(dir_path: []const u8) ChangeCurDirError!void { if (builtin.os.tag == .wasi and !builtin.link_libc) { var buf: [MAX_PATH_BYTES]u8 = undefined; var alloc = std.heap.FixedBufferAllocator.init(&buf); const path = try fs.resolve(alloc.allocator(), &.{ wasi_cwd.cwd, dir_path }); const dirinfo = try fstatat(AT.FDCWD, path, 0); if (dirinfo.filetype != .DIRECTORY) { return error.NotDir; } var cwd_alloc = std.heap.FixedBufferAllocator.init(&wasi_cwd.path_buffer); wasi_cwd.cwd = try cwd_alloc.allocator().dupe(u8, path); return; } else if (builtin.os.tag == .windows) { var utf16_dir_path: [windows.PATH_MAX_WIDE]u16 = undefined; const len = try std.unicode.utf8ToUtf16Le(utf16_dir_path[0..], dir_path); if (len > utf16_dir_path.len) return error.NameTooLong; return chdirW(utf16_dir_path[0..len]); } else { const dir_path_c = try toPosixPath(dir_path); return chdirZ(&dir_path_c); } } /// Same as `chdir` except the parameter is null-terminated. pub fn chdirZ(dir_path: [*:0]const u8) ChangeCurDirError!void { if (builtin.os.tag == .windows) { var utf16_dir_path: [windows.PATH_MAX_WIDE]u16 = undefined; const len = try std.unicode.utf8ToUtf16Le(utf16_dir_path[0..], dir_path); if (len > utf16_dir_path.len) return error.NameTooLong; return chdirW(utf16_dir_path[0..len]); } else if (builtin.os.tag == .wasi and !builtin.link_libc) { return chdir(mem.sliceTo(dir_path, 0)); } switch (errno(system.chdir(dir_path))) { .SUCCESS => return, .ACCES => return error.AccessDenied, .FAULT => unreachable, .IO => return error.FileSystem, .LOOP => return error.SymLinkLoop, .NAMETOOLONG => return error.NameTooLong, .NOENT => return error.FileNotFound, .NOMEM => return error.SystemResources, .NOTDIR => return error.NotDir, else => |err| return unexpectedErrno(err), } } /// Windows-only. Same as `chdir` except the paramter is WTF16 encoded. pub fn chdirW(dir_path: []const u16) ChangeCurDirError!void { windows.SetCurrentDirectory(dir_path) catch |err| switch (err) { error.NoDevice => return error.FileSystem, else => |e| return e, }; } pub const FchdirError = error{ AccessDenied, NotDir, FileSystem, } || UnexpectedError; pub fn fchdir(dirfd: fd_t) FchdirError!void { while (true) { switch (errno(system.fchdir(dirfd))) { .SUCCESS => return, .ACCES => return error.AccessDenied, .BADF => unreachable, .NOTDIR => return error.NotDir, .INTR => continue, .IO => return error.FileSystem, else => |err| return unexpectedErrno(err), } } } pub const ReadLinkError = error{ /// In WASI, this error may occur when the file descriptor does /// not hold the required rights to read value of a symbolic link relative to it. AccessDenied, FileSystem, SymLinkLoop, NameTooLong, FileNotFound, SystemResources, NotLink, NotDir, InvalidUtf8, BadPathName, /// Windows-only. This error may occur if the opened reparse point is /// of unsupported type. UnsupportedReparsePointType, } || UnexpectedError; /// Read value of a symbolic link. /// The return value is a slice of `out_buffer` from index 0. pub fn readlink(file_path: []const u8, out_buffer: []u8) ReadLinkError![]u8 { if (builtin.os.tag == .wasi and !builtin.link_libc) { return readlinkat(wasi.AT.FDCWD, file_path, out_buffer); } else if (builtin.os.tag == .windows) { const file_path_w = try windows.sliceToPrefixedFileW(file_path); return readlinkW(file_path_w.span(), out_buffer); } else { const file_path_c = try toPosixPath(file_path); return readlinkZ(&file_path_c, out_buffer); } } /// Windows-only. Same as `readlink` except `file_path` is WTF16 encoded. /// See also `readlinkZ`. pub fn readlinkW(file_path: []const u16, out_buffer: []u8) ReadLinkError![]u8 { return windows.ReadLink(std.fs.cwd().fd, file_path, out_buffer); } /// Same as `readlink` except `file_path` is null-terminated. pub fn readlinkZ(file_path: [*:0]const u8, out_buffer: []u8) ReadLinkError![]u8 { if (builtin.os.tag == .windows) { const file_path_w = try windows.cStrToWin32PrefixedFileW(file_path); return readlinkW(file_path_w.span(), out_buffer); } else if (builtin.os.tag == .wasi and !builtin.link_libc) { return readlink(mem.sliceTo(file_path, 0), out_buffer); } const rc = system.readlink(file_path, out_buffer.ptr, out_buffer.len); switch (errno(rc)) { .SUCCESS => return out_buffer[0..@bitCast(usize, rc)], .ACCES => return error.AccessDenied, .FAULT => unreachable, .INVAL => return error.NotLink, .IO => return error.FileSystem, .LOOP => return error.SymLinkLoop, .NAMETOOLONG => return error.NameTooLong, .NOENT => return error.FileNotFound, .NOMEM => return error.SystemResources, .NOTDIR => return error.NotDir, else => |err| return unexpectedErrno(err), } } /// Similar to `readlink` except reads value of a symbolink link **relative** to `dirfd` directory handle. /// The return value is a slice of `out_buffer` from index 0. /// See also `readlinkatWasi`, `realinkatZ` and `realinkatW`. pub fn readlinkat(dirfd: fd_t, file_path: []const u8, out_buffer: []u8) ReadLinkError![]u8 { if (builtin.os.tag == .wasi and !builtin.link_libc) { if (dirfd == wasi.AT.FDCWD or fs.path.isAbsolute(file_path)) { // Resolve absolute or CWD-relative paths to a path within a Preopen var path_buf: [MAX_PATH_BYTES]u8 = undefined; var path = try resolvePathWasi(file_path, &path_buf); return readlinkatWasi(path.dir_fd, path.relative_path, out_buffer); } return readlinkatWasi(dirfd, file_path, out_buffer); } if (builtin.os.tag == .windows) { const file_path_w = try windows.sliceToPrefixedFileW(file_path); return readlinkatW(dirfd, file_path_w.span(), out_buffer); } const file_path_c = try toPosixPath(file_path); return readlinkatZ(dirfd, &file_path_c, out_buffer); } /// WASI-only. Same as `readlinkat` but targets WASI. /// See also `readlinkat`. pub fn readlinkatWasi(dirfd: fd_t, file_path: []const u8, out_buffer: []u8) ReadLinkError![]u8 { var bufused: usize = undefined; switch (wasi.path_readlink(dirfd, file_path.ptr, file_path.len, out_buffer.ptr, out_buffer.len, &bufused)) { .SUCCESS => return out_buffer[0..bufused], .ACCES => return error.AccessDenied, .FAULT => unreachable, .INVAL => return error.NotLink, .IO => return error.FileSystem, .LOOP => return error.SymLinkLoop, .NAMETOOLONG => return error.NameTooLong, .NOENT => return error.FileNotFound, .NOMEM => return error.SystemResources, .NOTDIR => return error.NotDir, .NOTCAPABLE => return error.AccessDenied, else => |err| return unexpectedErrno(err), } } /// Windows-only. Same as `readlinkat` except `file_path` is null-terminated, WTF16 encoded. /// See also `readlinkat`. pub fn readlinkatW(dirfd: fd_t, file_path: []const u16, out_buffer: []u8) ReadLinkError![]u8 { return windows.ReadLink(dirfd, file_path, out_buffer); } /// Same as `readlinkat` except `file_path` is null-terminated. /// See also `readlinkat`. pub fn readlinkatZ(dirfd: fd_t, file_path: [*:0]const u8, out_buffer: []u8) ReadLinkError![]u8 { if (builtin.os.tag == .windows) { const file_path_w = try windows.cStrToPrefixedFileW(file_path); return readlinkatW(dirfd, file_path_w.span(), out_buffer); } else if (builtin.os.tag == .wasi and !builtin.link_libc) { return readlinkat(dirfd, mem.sliceTo(file_path, 0), out_buffer); } const rc = system.readlinkat(dirfd, file_path, out_buffer.ptr, out_buffer.len); switch (errno(rc)) { .SUCCESS => return out_buffer[0..@bitCast(usize, rc)], .ACCES => return error.AccessDenied, .FAULT => unreachable, .INVAL => return error.NotLink, .IO => return error.FileSystem, .LOOP => return error.SymLinkLoop, .NAMETOOLONG => return error.NameTooLong, .NOENT => return error.FileNotFound, .NOMEM => return error.SystemResources, .NOTDIR => return error.NotDir, else => |err| return unexpectedErrno(err), } } pub const SetEidError = error{ InvalidUserId, PermissionDenied, } || UnexpectedError; pub const SetIdError = error{ResourceLimitReached} || SetEidError; pub fn setuid(uid: uid_t) SetIdError!void { switch (errno(system.setuid(uid))) { .SUCCESS => return, .AGAIN => return error.ResourceLimitReached, .INVAL => return error.InvalidUserId, .PERM => return error.PermissionDenied, else => |err| return unexpectedErrno(err), } } pub fn seteuid(uid: uid_t) SetEidError!void { switch (errno(system.seteuid(uid))) { .SUCCESS => return, .INVAL => return error.InvalidUserId, .PERM => return error.PermissionDenied, else => |err| return unexpectedErrno(err), } } pub fn setreuid(ruid: uid_t, euid: uid_t) SetIdError!void { switch (errno(system.setreuid(ruid, euid))) { .SUCCESS => return, .AGAIN => return error.ResourceLimitReached, .INVAL => return error.InvalidUserId, .PERM => return error.PermissionDenied, else => |err| return unexpectedErrno(err), } } pub fn setgid(gid: gid_t) SetIdError!void { switch (errno(system.setgid(gid))) { .SUCCESS => return, .AGAIN => return error.ResourceLimitReached, .INVAL => return error.InvalidUserId, .PERM => return error.PermissionDenied, else => |err| return unexpectedErrno(err), } } pub fn setegid(uid: uid_t) SetEidError!void { switch (errno(system.setegid(uid))) { .SUCCESS => return, .INVAL => return error.InvalidUserId, .PERM => return error.PermissionDenied, else => |err| return unexpectedErrno(err), } } pub fn setregid(rgid: gid_t, egid: gid_t) SetIdError!void { switch (errno(system.setregid(rgid, egid))) { .SUCCESS => return, .AGAIN => return error.ResourceLimitReached, .INVAL => return error.InvalidUserId, .PERM => return error.PermissionDenied, else => |err| return unexpectedErrno(err), } } /// Test whether a file descriptor refers to a terminal. pub fn isatty(handle: fd_t) bool { if (builtin.os.tag == .windows) { if (isCygwinPty(handle)) return true; var out: windows.DWORD = undefined; return windows.kernel32.GetConsoleMode(handle, &out) != 0; } if (builtin.link_libc) { return system.isatty(handle) != 0; } if (builtin.os.tag == .wasi) { var statbuf: fdstat_t = undefined; const err = system.fd_fdstat_get(handle, &statbuf); if (err != 0) { // errno = err; return false; } // A tty is a character device that we can't seek or tell on. if (statbuf.fs_filetype != .CHARACTER_DEVICE or (statbuf.fs_rights_base & (RIGHT.FD_SEEK | RIGHT.FD_TELL)) != 0) { // errno = ENOTTY; return false; } return true; } if (builtin.os.tag == .linux) { while (true) { var wsz: linux.winsize = undefined; const fd = @bitCast(usize, @as(isize, handle)); const rc = linux.syscall3(.ioctl, fd, linux.T.IOCGWINSZ, @ptrToInt(&wsz)); switch (linux.getErrno(rc)) { .SUCCESS => return true, .INTR => continue, else => return false, } } } return system.isatty(handle) != 0; } pub fn isCygwinPty(handle: fd_t) bool { if (builtin.os.tag != .windows) return false; const size = @sizeOf(windows.FILE_NAME_INFO); var name_info_bytes align(@alignOf(windows.FILE_NAME_INFO)) = [_]u8{0} ** (size + windows.MAX_PATH); if (windows.kernel32.GetFileInformationByHandleEx( handle, windows.FileNameInfo, @ptrCast(*anyopaque, &name_info_bytes), name_info_bytes.len, ) == 0) { return false; } const name_info = @ptrCast(*const windows.FILE_NAME_INFO, &name_info_bytes[0]); const name_bytes = name_info_bytes[size .. size + @as(usize, name_info.FileNameLength)]; const name_wide = mem.bytesAsSlice(u16, name_bytes); return mem.indexOf(u16, name_wide, &[_]u16{ 'm', 's', 'y', 's', '-' }) != null or mem.indexOf(u16, name_wide, &[_]u16{ '-', 'p', 't', 'y' }) != null; } pub const SocketError = error{ /// Permission to create a socket of the specified type and/or /// pro‐tocol is denied. PermissionDenied, /// The implementation does not support the specified address family. AddressFamilyNotSupported, /// Unknown protocol, or protocol family not available. ProtocolFamilyNotAvailable, /// The per-process limit on the number of open file descriptors has been reached. ProcessFdQuotaExceeded, /// The system-wide limit on the total number of open files has been reached. SystemFdQuotaExceeded, /// Insufficient memory is available. The socket cannot be created until sufficient /// resources are freed. SystemResources, /// The protocol type or the specified protocol is not supported within this domain. ProtocolNotSupported, /// The socket type is not supported by the protocol. SocketTypeNotSupported, } || UnexpectedError; pub fn socket(domain: u32, socket_type: u32, protocol: u32) SocketError!socket_t { if (builtin.os.tag == .windows) { // NOTE: windows translates the SOCK.NONBLOCK/SOCK.CLOEXEC flags into // windows-analagous operations const filtered_sock_type = socket_type & ~@as(u32, SOCK.NONBLOCK | SOCK.CLOEXEC); const flags: u32 = if ((socket_type & SOCK.CLOEXEC) != 0) windows.ws2_32.WSA_FLAG_NO_HANDLE_INHERIT else 0; const rc = try windows.WSASocketW( @bitCast(i32, domain), @bitCast(i32, filtered_sock_type), @bitCast(i32, protocol), null, 0, flags, ); errdefer windows.closesocket(rc) catch unreachable; if ((socket_type & SOCK.NONBLOCK) != 0) { var mode: c_ulong = 1; // nonblocking if (windows.ws2_32.SOCKET_ERROR == windows.ws2_32.ioctlsocket(rc, windows.ws2_32.FIONBIO, &mode)) { switch (windows.ws2_32.WSAGetLastError()) { // have not identified any error codes that should be handled yet else => unreachable, } } } return rc; } const have_sock_flags = comptime !builtin.target.isDarwin(); const filtered_sock_type = if (!have_sock_flags) socket_type & ~@as(u32, SOCK.NONBLOCK | SOCK.CLOEXEC) else socket_type; const rc = system.socket(domain, filtered_sock_type, protocol); switch (errno(rc)) { .SUCCESS => { const fd = @intCast(fd_t, rc); if (!have_sock_flags) { try setSockFlags(fd, socket_type); } return fd; }, .ACCES => return error.PermissionDenied, .AFNOSUPPORT => return error.AddressFamilyNotSupported, .INVAL => return error.ProtocolFamilyNotAvailable, .MFILE => return error.ProcessFdQuotaExceeded, .NFILE => return error.SystemFdQuotaExceeded, .NOBUFS => return error.SystemResources, .NOMEM => return error.SystemResources, .PROTONOSUPPORT => return error.ProtocolNotSupported, .PROTOTYPE => return error.SocketTypeNotSupported, else => |err| return unexpectedErrno(err), } } pub const ShutdownError = error{ ConnectionAborted, /// Connection was reset by peer, application should close socket as it is no longer usable. ConnectionResetByPeer, BlockingOperationInProgress, /// The network subsystem has failed. NetworkSubsystemFailed, /// The socket is not connected (connection-oriented sockets only). SocketNotConnected, SystemResources, } || UnexpectedError; pub const ShutdownHow = enum { recv, send, both }; /// Shutdown socket send/receive operations pub fn shutdown(sock: socket_t, how: ShutdownHow) ShutdownError!void { if (builtin.os.tag == .windows) { const result = windows.ws2_32.shutdown(sock, switch (how) { .recv => windows.ws2_32.SD_RECEIVE, .send => windows.ws2_32.SD_SEND, .both => windows.ws2_32.SD_BOTH, }); if (0 != result) switch (windows.ws2_32.WSAGetLastError()) { .WSAECONNABORTED => return error.ConnectionAborted, .WSAECONNRESET => return error.ConnectionResetByPeer, .WSAEINPROGRESS => return error.BlockingOperationInProgress, .WSAEINVAL => unreachable, .WSAENETDOWN => return error.NetworkSubsystemFailed, .WSAENOTCONN => return error.SocketNotConnected, .WSAENOTSOCK => unreachable, .WSANOTINITIALISED => unreachable, else => |err| return windows.unexpectedWSAError(err), }; } else { const rc = system.shutdown(sock, switch (how) { .recv => SHUT.RD, .send => SHUT.WR, .both => SHUT.RDWR, }); switch (errno(rc)) { .SUCCESS => return, .BADF => unreachable, .INVAL => unreachable, .NOTCONN => return error.SocketNotConnected, .NOTSOCK => unreachable, .NOBUFS => return error.SystemResources, else => |err| return unexpectedErrno(err), } } } pub fn closeSocket(sock: socket_t) void { if (builtin.os.tag == .windows) { windows.closesocket(sock) catch unreachable; } else { close(sock); } } pub const BindError = error{ /// The address is protected, and the user is not the superuser. /// For UNIX domain sockets: Search permission is denied on a component /// of the path prefix. AccessDenied, /// The given address is already in use, or in the case of Internet domain sockets, /// The port number was specified as zero in the socket /// address structure, but, upon attempting to bind to an ephemeral port, it was /// determined that all port numbers in the ephemeral port range are currently in /// use. See the discussion of /proc/sys/net/ipv4/ip_local_port_range ip(7). AddressInUse, /// A nonexistent interface was requested or the requested address was not local. AddressNotAvailable, /// The address is not valid for the address family of socket. AddressFamilyNotSupported, /// Too many symbolic links were encountered in resolving addr. SymLinkLoop, /// addr is too long. NameTooLong, /// A component in the directory prefix of the socket pathname does not exist. FileNotFound, /// Insufficient kernel memory was available. SystemResources, /// A component of the path prefix is not a directory. NotDir, /// The socket inode would reside on a read-only filesystem. ReadOnlyFileSystem, /// The network subsystem has failed. NetworkSubsystemFailed, FileDescriptorNotASocket, AlreadyBound, } || UnexpectedError; /// addr is `*const T` where T is one of the sockaddr pub fn bind(sock: socket_t, addr: *const sockaddr, len: socklen_t) BindError!void { if (builtin.os.tag == .windows) { const rc = windows.bind(sock, addr, len); if (rc == windows.ws2_32.SOCKET_ERROR) { switch (windows.ws2_32.WSAGetLastError()) { .WSANOTINITIALISED => unreachable, // not initialized WSA .WSAEACCES => return error.AccessDenied, .WSAEADDRINUSE => return error.AddressInUse, .WSAEADDRNOTAVAIL => return error.AddressNotAvailable, .WSAENOTSOCK => return error.FileDescriptorNotASocket, .WSAEFAULT => unreachable, // invalid pointers .WSAEINVAL => return error.AlreadyBound, .WSAENOBUFS => return error.SystemResources, .WSAENETDOWN => return error.NetworkSubsystemFailed, else => |err| return windows.unexpectedWSAError(err), } unreachable; } return; } else { const rc = system.bind(sock, addr, len); switch (errno(rc)) { .SUCCESS => return, .ACCES => return error.AccessDenied, .ADDRINUSE => return error.AddressInUse, .BADF => unreachable, // always a race condition if this error is returned .INVAL => unreachable, // invalid parameters .NOTSOCK => unreachable, // invalid `sockfd` .AFNOSUPPORT => return error.AddressFamilyNotSupported, .ADDRNOTAVAIL => return error.AddressNotAvailable, .FAULT => unreachable, // invalid `addr` pointer .LOOP => return error.SymLinkLoop, .NAMETOOLONG => return error.NameTooLong, .NOENT => return error.FileNotFound, .NOMEM => return error.SystemResources, .NOTDIR => return error.NotDir, .ROFS => return error.ReadOnlyFileSystem, else => |err| return unexpectedErrno(err), } } unreachable; } pub const ListenError = error{ /// Another socket is already listening on the same port. /// For Internet domain sockets, the socket referred to by sockfd had not previously /// been bound to an address and, upon attempting to bind it to an ephemeral port, it /// was determined that all port numbers in the ephemeral port range are currently in /// use. See the discussion of /proc/sys/net/ipv4/ip_local_port_range in ip(7). AddressInUse, /// The file descriptor sockfd does not refer to a socket. FileDescriptorNotASocket, /// The socket is not of a type that supports the listen() operation. OperationNotSupported, /// The network subsystem has failed. NetworkSubsystemFailed, /// Ran out of system resources /// On Windows it can either run out of socket descriptors or buffer space SystemResources, /// Already connected AlreadyConnected, /// Socket has not been bound yet SocketNotBound, } || UnexpectedError; pub fn listen(sock: socket_t, backlog: u31) ListenError!void { if (builtin.os.tag == .windows) { const rc = windows.listen(sock, backlog); if (rc == windows.ws2_32.SOCKET_ERROR) { switch (windows.ws2_32.WSAGetLastError()) { .WSANOTINITIALISED => unreachable, // not initialized WSA .WSAENETDOWN => return error.NetworkSubsystemFailed, .WSAEADDRINUSE => return error.AddressInUse, .WSAEISCONN => return error.AlreadyConnected, .WSAEINVAL => return error.SocketNotBound, .WSAEMFILE, .WSAENOBUFS => return error.SystemResources, .WSAENOTSOCK => return error.FileDescriptorNotASocket, .WSAEOPNOTSUPP => return error.OperationNotSupported, .WSAEINPROGRESS => unreachable, else => |err| return windows.unexpectedWSAError(err), } } return; } else { const rc = system.listen(sock, backlog); switch (errno(rc)) { .SUCCESS => return, .ADDRINUSE => return error.AddressInUse, .BADF => unreachable, .NOTSOCK => return error.FileDescriptorNotASocket, .OPNOTSUPP => return error.OperationNotSupported, else => |err| return unexpectedErrno(err), } } } pub const AcceptError = error{ ConnectionAborted, /// The file descriptor sockfd does not refer to a socket. FileDescriptorNotASocket, /// The per-process limit on the number of open file descriptors has been reached. ProcessFdQuotaExceeded, /// The system-wide limit on the total number of open files has been reached. SystemFdQuotaExceeded, /// Not enough free memory. This often means that the memory allocation is limited /// by the socket buffer limits, not by the system memory. SystemResources, /// Socket is not listening for new connections. SocketNotListening, ProtocolFailure, /// Firewall rules forbid connection. BlockedByFirewall, /// This error occurs when no global event loop is configured, /// and accepting from the socket would block. WouldBlock, /// An incoming connection was indicated, but was subsequently terminated by the /// remote peer prior to accepting the call. ConnectionResetByPeer, /// The network subsystem has failed. NetworkSubsystemFailed, /// The referenced socket is not a type that supports connection-oriented service. OperationNotSupported, } || UnexpectedError; /// Accept a connection on a socket. /// If `sockfd` is opened in non blocking mode, the function will /// return error.WouldBlock when EAGAIN is received. pub fn accept( /// This argument is a socket that has been created with `socket`, bound to a local address /// with `bind`, and is listening for connections after a `listen`. sock: socket_t, /// This argument is a pointer to a sockaddr structure. This structure is filled in with the /// address of the peer socket, as known to the communications layer. The exact format of the /// address returned addr is determined by the socket's address family (see `socket` and the /// respective protocol man pages). addr: ?*sockaddr, /// This argument is a value-result argument: the caller must initialize it to contain the /// size (in bytes) of the structure pointed to by addr; on return it will contain the actual size /// of the peer address. /// /// The returned address is truncated if the buffer provided is too small; in this case, `addr_size` /// will return a value greater than was supplied to the call. addr_size: ?*socklen_t, /// The following values can be bitwise ORed in flags to obtain different behavior: /// * `SOCK.NONBLOCK` - Set the `O.NONBLOCK` file status flag on the open file description (see `open`) /// referred to by the new file descriptor. Using this flag saves extra calls to `fcntl` to achieve /// the same result. /// * `SOCK.CLOEXEC` - Set the close-on-exec (`FD_CLOEXEC`) flag on the new file descriptor. See the /// description of the `O.CLOEXEC` flag in `open` for reasons why this may be useful. flags: u32, ) AcceptError!socket_t { const have_accept4 = comptime !(builtin.target.isDarwin() or builtin.os.tag == .windows); assert(0 == (flags & ~@as(u32, SOCK.NONBLOCK | SOCK.CLOEXEC))); // Unsupported flag(s) const accepted_sock = while (true) { const rc = if (have_accept4) system.accept4(sock, addr, addr_size, flags) else if (builtin.os.tag == .windows) windows.accept(sock, addr, addr_size) else system.accept(sock, addr, addr_size); if (builtin.os.tag == .windows) { if (rc == windows.ws2_32.INVALID_SOCKET) { switch (windows.ws2_32.WSAGetLastError()) { .WSANOTINITIALISED => unreachable, // not initialized WSA .WSAECONNRESET => return error.ConnectionResetByPeer, .WSAEFAULT => unreachable, .WSAEINVAL => return error.SocketNotListening, .WSAEMFILE => return error.ProcessFdQuotaExceeded, .WSAENETDOWN => return error.NetworkSubsystemFailed, .WSAENOBUFS => return error.FileDescriptorNotASocket, .WSAEOPNOTSUPP => return error.OperationNotSupported, .WSAEWOULDBLOCK => return error.WouldBlock, else => |err| return windows.unexpectedWSAError(err), } } else { break rc; } } else { switch (errno(rc)) { .SUCCESS => { break @intCast(socket_t, rc); }, .INTR => continue, .AGAIN => return error.WouldBlock, .BADF => unreachable, // always a race condition .CONNABORTED => return error.ConnectionAborted, .FAULT => unreachable, .INVAL => return error.SocketNotListening, .NOTSOCK => unreachable, .MFILE => return error.ProcessFdQuotaExceeded, .NFILE => return error.SystemFdQuotaExceeded, .NOBUFS => return error.SystemResources, .NOMEM => return error.SystemResources, .OPNOTSUPP => unreachable, .PROTO => return error.ProtocolFailure, .PERM => return error.BlockedByFirewall, else => |err| return unexpectedErrno(err), } } } else unreachable; if (!have_accept4) { try setSockFlags(accepted_sock, flags); } return accepted_sock; } pub const EpollCreateError = error{ /// The per-user limit on the number of epoll instances imposed by /// /proc/sys/fs/epoll/max_user_instances was encountered. See epoll(7) for further /// details. /// Or, The per-process limit on the number of open file descriptors has been reached. ProcessFdQuotaExceeded, /// The system-wide limit on the total number of open files has been reached. SystemFdQuotaExceeded, /// There was insufficient memory to create the kernel object. SystemResources, } || UnexpectedError; pub fn epoll_create1(flags: u32) EpollCreateError!i32 { const rc = system.epoll_create1(flags); switch (errno(rc)) { .SUCCESS => return @intCast(i32, rc), else => |err| return unexpectedErrno(err), .INVAL => unreachable, .MFILE => return error.ProcessFdQuotaExceeded, .NFILE => return error.SystemFdQuotaExceeded, .NOMEM => return error.SystemResources, } } pub const EpollCtlError = error{ /// op was EPOLL_CTL_ADD, and the supplied file descriptor fd is already registered /// with this epoll instance. FileDescriptorAlreadyPresentInSet, /// fd refers to an epoll instance and this EPOLL_CTL_ADD operation would result in a /// circular loop of epoll instances monitoring one another. OperationCausesCircularLoop, /// op was EPOLL_CTL_MOD or EPOLL_CTL_DEL, and fd is not registered with this epoll /// instance. FileDescriptorNotRegistered, /// There was insufficient memory to handle the requested op control operation. SystemResources, /// The limit imposed by /proc/sys/fs/epoll/max_user_watches was encountered while /// trying to register (EPOLL_CTL_ADD) a new file descriptor on an epoll instance. /// See epoll(7) for further details. UserResourceLimitReached, /// The target file fd does not support epoll. This error can occur if fd refers to, /// for example, a regular file or a directory. FileDescriptorIncompatibleWithEpoll, } || UnexpectedError; pub fn epoll_ctl(epfd: i32, op: u32, fd: i32, event: ?*linux.epoll_event) EpollCtlError!void { const rc = system.epoll_ctl(epfd, op, fd, event); switch (errno(rc)) { .SUCCESS => return, else => |err| return unexpectedErrno(err), .BADF => unreachable, // always a race condition if this happens .EXIST => return error.FileDescriptorAlreadyPresentInSet, .INVAL => unreachable, .LOOP => return error.OperationCausesCircularLoop, .NOENT => return error.FileDescriptorNotRegistered, .NOMEM => return error.SystemResources, .NOSPC => return error.UserResourceLimitReached, .PERM => return error.FileDescriptorIncompatibleWithEpoll, } } /// Waits for an I/O event on an epoll file descriptor. /// Returns the number of file descriptors ready for the requested I/O, /// or zero if no file descriptor became ready during the requested timeout milliseconds. pub fn epoll_wait(epfd: i32, events: []linux.epoll_event, timeout: i32) usize { while (true) { // TODO get rid of the @intCast const rc = system.epoll_wait(epfd, events.ptr, @intCast(u32, events.len), timeout); switch (errno(rc)) { .SUCCESS => return @intCast(usize, rc), .INTR => continue, .BADF => unreachable, .FAULT => unreachable, .INVAL => unreachable, else => unreachable, } } } pub const EventFdError = error{ SystemResources, ProcessFdQuotaExceeded, SystemFdQuotaExceeded, } || UnexpectedError; pub fn eventfd(initval: u32, flags: u32) EventFdError!i32 { const rc = system.eventfd(initval, flags); switch (errno(rc)) { .SUCCESS => return @intCast(i32, rc), else => |err| return unexpectedErrno(err), .INVAL => unreachable, // invalid parameters .MFILE => return error.ProcessFdQuotaExceeded, .NFILE => return error.SystemFdQuotaExceeded, .NODEV => return error.SystemResources, .NOMEM => return error.SystemResources, } } pub const GetSockNameError = error{ /// Insufficient resources were available in the system to perform the operation. SystemResources, /// The network subsystem has failed. NetworkSubsystemFailed, /// Socket hasn't been bound yet SocketNotBound, FileDescriptorNotASocket, } || UnexpectedError; pub fn getsockname(sock: socket_t, addr: *sockaddr, addrlen: *socklen_t) GetSockNameError!void { if (builtin.os.tag == .windows) { const rc = windows.getsockname(sock, addr, addrlen); if (rc == windows.ws2_32.SOCKET_ERROR) { switch (windows.ws2_32.WSAGetLastError()) { .WSANOTINITIALISED => unreachable, .WSAENETDOWN => return error.NetworkSubsystemFailed, .WSAEFAULT => unreachable, // addr or addrlen have invalid pointers or addrlen points to an incorrect value .WSAENOTSOCK => return error.FileDescriptorNotASocket, .WSAEINVAL => return error.SocketNotBound, else => |err| return windows.unexpectedWSAError(err), } } return; } else { const rc = system.getsockname(sock, addr, addrlen); switch (errno(rc)) { .SUCCESS => return, else => |err| return unexpectedErrno(err), .BADF => unreachable, // always a race condition .FAULT => unreachable, .INVAL => unreachable, // invalid parameters .NOTSOCK => return error.FileDescriptorNotASocket, .NOBUFS => return error.SystemResources, } } } pub fn getpeername(sock: socket_t, addr: *sockaddr, addrlen: *socklen_t) GetSockNameError!void { if (builtin.os.tag == .windows) { const rc = windows.getpeername(sock, addr, addrlen); if (rc == windows.ws2_32.SOCKET_ERROR) { switch (windows.ws2_32.WSAGetLastError()) { .WSANOTINITIALISED => unreachable, .WSAENETDOWN => return error.NetworkSubsystemFailed, .WSAEFAULT => unreachable, // addr or addrlen have invalid pointers or addrlen points to an incorrect value .WSAENOTSOCK => return error.FileDescriptorNotASocket, .WSAEINVAL => return error.SocketNotBound, else => |err| return windows.unexpectedWSAError(err), } } return; } else { const rc = system.getpeername(sock, addr, addrlen); switch (errno(rc)) { .SUCCESS => return, else => |err| return unexpectedErrno(err), .BADF => unreachable, // always a race condition .FAULT => unreachable, .INVAL => unreachable, // invalid parameters .NOTSOCK => return error.FileDescriptorNotASocket, .NOBUFS => return error.SystemResources, } } } pub const ConnectError = error{ /// For UNIX domain sockets, which are identified by pathname: Write permission is denied on the socket /// file, or search permission is denied for one of the directories in the path prefix. /// or /// The user tried to connect to a broadcast address without having the socket broadcast flag enabled or /// the connection request failed because of a local firewall rule. PermissionDenied, /// Local address is already in use. AddressInUse, /// (Internet domain sockets) The socket referred to by sockfd had not previously been bound to an /// address and, upon attempting to bind it to an ephemeral port, it was determined that all port numbers /// in the ephemeral port range are currently in use. See the discussion of /// /proc/sys/net/ipv4/ip_local_port_range in ip(7). AddressNotAvailable, /// The passed address didn't have the correct address family in its sa_family field. AddressFamilyNotSupported, /// Insufficient entries in the routing cache. SystemResources, /// A connect() on a stream socket found no one listening on the remote address. ConnectionRefused, /// Network is unreachable. NetworkUnreachable, /// Timeout while attempting connection. The server may be too busy to accept new connections. Note /// that for IP sockets the timeout may be very long when syncookies are enabled on the server. ConnectionTimedOut, /// This error occurs when no global event loop is configured, /// and connecting to the socket would block. WouldBlock, /// The given path for the unix socket does not exist. FileNotFound, /// Connection was reset by peer before connect could complete. ConnectionResetByPeer, /// Socket is non-blocking and already has a pending connection in progress. ConnectionPending, } || UnexpectedError; /// Initiate a connection on a socket. /// If `sockfd` is opened in non blocking mode, the function will /// return error.WouldBlock when EAGAIN or EINPROGRESS is received. pub fn connect(sock: socket_t, sock_addr: *const sockaddr, len: socklen_t) ConnectError!void { if (builtin.os.tag == .windows) { const rc = windows.ws2_32.connect(sock, sock_addr, @intCast(i32, len)); if (rc == 0) return; switch (windows.ws2_32.WSAGetLastError()) { .WSAEADDRINUSE => return error.AddressInUse, .WSAEADDRNOTAVAIL => return error.AddressNotAvailable, .WSAECONNREFUSED => return error.ConnectionRefused, .WSAECONNRESET => return error.ConnectionResetByPeer, .WSAETIMEDOUT => return error.ConnectionTimedOut, .WSAEHOSTUNREACH, // TODO: should we return NetworkUnreachable in this case as well? .WSAENETUNREACH, => return error.NetworkUnreachable, .WSAEFAULT => unreachable, .WSAEINVAL => unreachable, .WSAEISCONN => unreachable, .WSAENOTSOCK => unreachable, .WSAEWOULDBLOCK => unreachable, .WSAEACCES => unreachable, .WSAENOBUFS => return error.SystemResources, .WSAEAFNOSUPPORT => return error.AddressFamilyNotSupported, else => |err| return windows.unexpectedWSAError(err), } return; } while (true) { switch (errno(system.connect(sock, sock_addr, len))) { .SUCCESS => return, .ACCES => return error.PermissionDenied, .PERM => return error.PermissionDenied, .ADDRINUSE => return error.AddressInUse, .ADDRNOTAVAIL => return error.AddressNotAvailable, .AFNOSUPPORT => return error.AddressFamilyNotSupported, .AGAIN, .INPROGRESS => return error.WouldBlock, .ALREADY => return error.ConnectionPending, .BADF => unreachable, // sockfd is not a valid open file descriptor. .CONNREFUSED => return error.ConnectionRefused, .CONNRESET => return error.ConnectionResetByPeer, .FAULT => unreachable, // The socket structure address is outside the user's address space. .INTR => continue, .ISCONN => unreachable, // The socket is already connected. .HOSTUNREACH => return error.NetworkUnreachable, .NETUNREACH => return error.NetworkUnreachable, .NOTSOCK => unreachable, // The file descriptor sockfd does not refer to a socket. .PROTOTYPE => unreachable, // The socket type does not support the requested communications protocol. .TIMEDOUT => return error.ConnectionTimedOut, .NOENT => return error.FileNotFound, // Returned when socket is AF.UNIX and the given path does not exist. else => |err| return unexpectedErrno(err), } } } pub fn getsockoptError(sockfd: fd_t) ConnectError!void { var err_code: i32 = undefined; var size: u32 = @sizeOf(u32); const rc = system.getsockopt(sockfd, SOL.SOCKET, SO.ERROR, @ptrCast([*]u8, &err_code), &size); assert(size == 4); switch (errno(rc)) { .SUCCESS => switch (@intToEnum(E, err_code)) { .SUCCESS => return, .ACCES => return error.PermissionDenied, .PERM => return error.PermissionDenied, .ADDRINUSE => return error.AddressInUse, .ADDRNOTAVAIL => return error.AddressNotAvailable, .AFNOSUPPORT => return error.AddressFamilyNotSupported, .AGAIN => return error.SystemResources, .ALREADY => return error.ConnectionPending, .BADF => unreachable, // sockfd is not a valid open file descriptor. .CONNREFUSED => return error.ConnectionRefused, .FAULT => unreachable, // The socket structure address is outside the user's address space. .ISCONN => unreachable, // The socket is already connected. .HOSTUNREACH => return error.NetworkUnreachable, .NETUNREACH => return error.NetworkUnreachable, .NOTSOCK => unreachable, // The file descriptor sockfd does not refer to a socket. .PROTOTYPE => unreachable, // The socket type does not support the requested communications protocol. .TIMEDOUT => return error.ConnectionTimedOut, .CONNRESET => return error.ConnectionResetByPeer, else => |err| return unexpectedErrno(err), }, .BADF => unreachable, // The argument sockfd is not a valid file descriptor. .FAULT => unreachable, // The address pointed to by optval or optlen is not in a valid part of the process address space. .INVAL => unreachable, .NOPROTOOPT => unreachable, // The option is unknown at the level indicated. .NOTSOCK => unreachable, // The file descriptor sockfd does not refer to a socket. else => |err| return unexpectedErrno(err), } } pub const WaitPidResult = struct { pid: pid_t, status: u32, }; /// Use this version of the `waitpid` wrapper if you spawned your child process using explicit /// `fork` and `execve` method. If you spawned your child process using `posix_spawn` method, /// use `std.os.posix_spawn.waitpid` instead. pub fn waitpid(pid: pid_t, flags: u32) WaitPidResult { const Status = if (builtin.link_libc) c_int else u32; var status: Status = undefined; while (true) { const rc = system.waitpid(pid, &status, if (builtin.link_libc) @intCast(c_int, flags) else flags); switch (errno(rc)) { .SUCCESS => return .{ .pid = @intCast(pid_t, rc), .status = @bitCast(u32, status), }, .INTR => continue, .CHILD => unreachable, // The process specified does not exist. It would be a race condition to handle this error. .INVAL => unreachable, // Invalid flags. else => unreachable, } } } pub const FStatError = error{ SystemResources, /// In WASI, this error may occur when the file descriptor does /// not hold the required rights to get its filestat information. AccessDenied, } || UnexpectedError; /// Return information about a file descriptor. pub fn fstat(fd: fd_t) FStatError!Stat { if (builtin.os.tag == .wasi and !builtin.link_libc) { var stat: wasi.filestat_t = undefined; switch (wasi.fd_filestat_get(fd, &stat)) { .SUCCESS => return Stat.fromFilestat(stat), .INVAL => unreachable, .BADF => unreachable, // Always a race condition. .NOMEM => return error.SystemResources, .ACCES => return error.AccessDenied, .NOTCAPABLE => return error.AccessDenied, else => |err| return unexpectedErrno(err), } } if (builtin.os.tag == .windows) { @compileError("fstat is not yet implemented on Windows"); } const fstat_sym = if (builtin.os.tag == .linux and builtin.link_libc) system.fstat64 else system.fstat; var stat = mem.zeroes(Stat); switch (errno(fstat_sym(fd, &stat))) { .SUCCESS => return stat, .INVAL => unreachable, .BADF => unreachable, // Always a race condition. .NOMEM => return error.SystemResources, .ACCES => return error.AccessDenied, else => |err| return unexpectedErrno(err), } } pub const FStatAtError = FStatError || error{ NameTooLong, FileNotFound, SymLinkLoop }; /// Similar to `fstat`, but returns stat of a resource pointed to by `pathname` /// which is relative to `dirfd` handle. /// See also `fstatatZ` and `fstatatWasi`. pub fn fstatat(dirfd: fd_t, pathname: []const u8, flags: u32) FStatAtError!Stat { if (builtin.os.tag == .wasi and !builtin.link_libc) { const wasi_flags = if (flags & linux.AT.SYMLINK_NOFOLLOW == 0) wasi.LOOKUP_SYMLINK_FOLLOW else 0; if (dirfd == wasi.AT.FDCWD or fs.path.isAbsolute(pathname)) { // Resolve absolute or CWD-relative paths to a path within a Preopen var path_buf: [MAX_PATH_BYTES]u8 = undefined; const path = try resolvePathWasi(pathname, &path_buf); return fstatatWasi(path.dir_fd, path.relative_path, wasi_flags); } return fstatatWasi(dirfd, pathname, wasi_flags); } else if (builtin.os.tag == .windows) { @compileError("fstatat is not yet implemented on Windows"); } else { const pathname_c = try toPosixPath(pathname); return fstatatZ(dirfd, &pathname_c, flags); } } /// WASI-only. Same as `fstatat` but targeting WASI. /// See also `fstatat`. pub fn fstatatWasi(dirfd: fd_t, pathname: []const u8, flags: u32) FStatAtError!Stat { var stat: wasi.filestat_t = undefined; switch (wasi.path_filestat_get(dirfd, flags, pathname.ptr, pathname.len, &stat)) { .SUCCESS => return Stat.fromFilestat(stat), .INVAL => unreachable, .BADF => unreachable, // Always a race condition. .NOMEM => return error.SystemResources, .ACCES => return error.AccessDenied, .FAULT => unreachable, .NAMETOOLONG => return error.NameTooLong, .NOENT => return error.FileNotFound, .NOTDIR => return error.FileNotFound, .NOTCAPABLE => return error.AccessDenied, else => |err| return unexpectedErrno(err), } } /// Same as `fstatat` but `pathname` is null-terminated. /// See also `fstatat`. pub fn fstatatZ(dirfd: fd_t, pathname: [*:0]const u8, flags: u32) FStatAtError!Stat { if (builtin.os.tag == .wasi and !builtin.link_libc) { return fstatatWasi(dirfd, mem.sliceTo(pathname), flags); } const fstatat_sym = if (builtin.os.tag == .linux and builtin.link_libc) system.fstatat64 else system.fstatat; var stat = mem.zeroes(Stat); switch (errno(fstatat_sym(dirfd, pathname, &stat, flags))) { .SUCCESS => return stat, .INVAL => unreachable, .BADF => unreachable, // Always a race condition. .NOMEM => return error.SystemResources, .ACCES => return error.AccessDenied, .PERM => return error.AccessDenied, .FAULT => unreachable, .NAMETOOLONG => return error.NameTooLong, .LOOP => return error.SymLinkLoop, .NOENT => return error.FileNotFound, .NOTDIR => return error.FileNotFound, else => |err| return unexpectedErrno(err), } } pub const KQueueError = error{ /// The per-process limit on the number of open file descriptors has been reached. ProcessFdQuotaExceeded, /// The system-wide limit on the total number of open files has been reached. SystemFdQuotaExceeded, } || UnexpectedError; pub fn kqueue() KQueueError!i32 { const rc = system.kqueue(); switch (errno(rc)) { .SUCCESS => return @intCast(i32, rc), .MFILE => return error.ProcessFdQuotaExceeded, .NFILE => return error.SystemFdQuotaExceeded, else => |err| return unexpectedErrno(err), } } pub const KEventError = error{ /// The process does not have permission to register a filter. AccessDenied, /// The event could not be found to be modified or deleted. EventNotFound, /// No memory was available to register the event. SystemResources, /// The specified process to attach to does not exist. ProcessNotFound, /// changelist or eventlist had too many items on it. /// TODO remove this possibility Overflow, }; pub fn kevent( kq: i32, changelist: []const Kevent, eventlist: []Kevent, timeout: ?*const timespec, ) KEventError!usize { while (true) { const rc = system.kevent( kq, changelist.ptr, math.cast(c_int, changelist.len) orelse return error.Overflow, eventlist.ptr, math.cast(c_int, eventlist.len) orelse return error.Overflow, timeout, ); switch (errno(rc)) { .SUCCESS => return @intCast(usize, rc), .ACCES => return error.AccessDenied, .FAULT => unreachable, .BADF => unreachable, // Always a race condition. .INTR => continue, .INVAL => unreachable, .NOENT => return error.EventNotFound, .NOMEM => return error.SystemResources, .SRCH => return error.ProcessNotFound, else => unreachable, } } } pub const INotifyInitError = error{ ProcessFdQuotaExceeded, SystemFdQuotaExceeded, SystemResources, } || UnexpectedError; /// initialize an inotify instance pub fn inotify_init1(flags: u32) INotifyInitError!i32 { const rc = system.inotify_init1(flags); switch (errno(rc)) { .SUCCESS => return @intCast(i32, rc), .INVAL => unreachable, .MFILE => return error.ProcessFdQuotaExceeded, .NFILE => return error.SystemFdQuotaExceeded, .NOMEM => return error.SystemResources, else => |err| return unexpectedErrno(err), } } pub const INotifyAddWatchError = error{ AccessDenied, NameTooLong, FileNotFound, SystemResources, UserResourceLimitReached, NotDir, WatchAlreadyExists, } || UnexpectedError; /// add a watch to an initialized inotify instance pub fn inotify_add_watch(inotify_fd: i32, pathname: []const u8, mask: u32) INotifyAddWatchError!i32 { const pathname_c = try toPosixPath(pathname); return inotify_add_watchZ(inotify_fd, &pathname_c, mask); } /// Same as `inotify_add_watch` except pathname is null-terminated. pub fn inotify_add_watchZ(inotify_fd: i32, pathname: [*:0]const u8, mask: u32) INotifyAddWatchError!i32 { const rc = system.inotify_add_watch(inotify_fd, pathname, mask); switch (errno(rc)) { .SUCCESS => return @intCast(i32, rc), .ACCES => return error.AccessDenied, .BADF => unreachable, .FAULT => unreachable, .INVAL => unreachable, .NAMETOOLONG => return error.NameTooLong, .NOENT => return error.FileNotFound, .NOMEM => return error.SystemResources, .NOSPC => return error.UserResourceLimitReached, .NOTDIR => return error.NotDir, .EXIST => return error.WatchAlreadyExists, else => |err| return unexpectedErrno(err), } } /// remove an existing watch from an inotify instance pub fn inotify_rm_watch(inotify_fd: i32, wd: i32) void { switch (errno(system.inotify_rm_watch(inotify_fd, wd))) { .SUCCESS => return, .BADF => unreachable, .INVAL => unreachable, else => unreachable, } } pub const MProtectError = error{ /// The memory cannot be given the specified access. This can happen, for example, if you /// mmap(2) a file to which you have read-only access, then ask mprotect() to mark it /// PROT_WRITE. AccessDenied, /// Changing the protection of a memory region would result in the total number of map‐ /// pings with distinct attributes (e.g., read versus read/write protection) exceeding the /// allowed maximum. (For example, making the protection of a range PROT_READ in the mid‐ /// dle of a region currently protected as PROT_READ|PROT_WRITE would result in three map‐ /// pings: two read/write mappings at each end and a read-only mapping in the middle.) OutOfMemory, } || UnexpectedError; /// `memory.len` must be page-aligned. pub fn mprotect(memory: []align(mem.page_size) u8, protection: u32) MProtectError!void { assert(mem.isAligned(memory.len, mem.page_size)); switch (errno(system.mprotect(memory.ptr, memory.len, protection))) { .SUCCESS => return, .INVAL => unreachable, .ACCES => return error.AccessDenied, .NOMEM => return error.OutOfMemory, else => |err| return unexpectedErrno(err), } } pub const ForkError = error{SystemResources} || UnexpectedError; pub fn fork() ForkError!pid_t { const rc = system.fork(); switch (errno(rc)) { .SUCCESS => return @intCast(pid_t, rc), .AGAIN => return error.SystemResources, .NOMEM => return error.SystemResources, else => |err| return unexpectedErrno(err), } } pub const MMapError = error{ /// The underlying filesystem of the specified file does not support memory mapping. MemoryMappingNotSupported, /// A file descriptor refers to a non-regular file. Or a file mapping was requested, /// but the file descriptor is not open for reading. Or `MAP.SHARED` was requested /// and `PROT_WRITE` is set, but the file descriptor is not open in `O.RDWR` mode. /// Or `PROT_WRITE` is set, but the file is append-only. AccessDenied, /// The `prot` argument asks for `PROT_EXEC` but the mapped area belongs to a file on /// a filesystem that was mounted no-exec. PermissionDenied, LockedMemoryLimitExceeded, OutOfMemory, } || UnexpectedError; /// Map files or devices into memory. /// `length` does not need to be aligned. /// Use of a mapped region can result in these signals: /// * SIGSEGV - Attempted write into a region mapped as read-only. /// * SIGBUS - Attempted access to a portion of the buffer that does not correspond to the file pub fn mmap( ptr: ?[*]align(mem.page_size) u8, length: usize, prot: u32, flags: u32, fd: fd_t, offset: u64, ) MMapError![]align(mem.page_size) u8 { const mmap_sym = if (builtin.os.tag == .linux and builtin.link_libc) system.mmap64 else system.mmap; const ioffset = @bitCast(i64, offset); // the OS treats this as unsigned const rc = mmap_sym(ptr, length, prot, flags, fd, ioffset); const err = if (builtin.link_libc) blk: { if (rc != std.c.MAP.FAILED) return @ptrCast([*]align(mem.page_size) u8, @alignCast(mem.page_size, rc))[0..length]; break :blk @intToEnum(E, system._errno().*); } else blk: { const err = errno(rc); if (err == .SUCCESS) return @intToPtr([*]align(mem.page_size) u8, rc)[0..length]; break :blk err; }; switch (err) { .SUCCESS => unreachable, .TXTBSY => return error.AccessDenied, .ACCES => return error.AccessDenied, .PERM => return error.PermissionDenied, .AGAIN => return error.LockedMemoryLimitExceeded, .BADF => unreachable, // Always a race condition. .OVERFLOW => unreachable, // The number of pages used for length + offset would overflow. .NODEV => return error.MemoryMappingNotSupported, .INVAL => unreachable, // Invalid parameters to mmap() .NOMEM => return error.OutOfMemory, else => return unexpectedErrno(err), } } /// Deletes the mappings for the specified address range, causing /// further references to addresses within the range to generate invalid memory references. /// Note that while POSIX allows unmapping a region in the middle of an existing mapping, /// Zig's munmap function does not, for two reasons: /// * It violates the Zig principle that resource deallocation must succeed. /// * The Windows function, VirtualFree, has this restriction. pub fn munmap(memory: []align(mem.page_size) const u8) void { switch (errno(system.munmap(memory.ptr, memory.len))) { .SUCCESS => return, .INVAL => unreachable, // Invalid parameters. .NOMEM => unreachable, // Attempted to unmap a region in the middle of an existing mapping. else => unreachable, } } pub const MSyncError = error{ UnmappedMemory, } || UnexpectedError; pub fn msync(memory: []align(mem.page_size) u8, flags: i32) MSyncError!void { switch (errno(system.msync(memory.ptr, memory.len, flags))) { .SUCCESS => return, .NOMEM => return error.UnmappedMemory, // Unsuccessful, provided pointer does not point mapped memory .INVAL => unreachable, // Invalid parameters. else => unreachable, } } pub const AccessError = error{ PermissionDenied, FileNotFound, NameTooLong, InputOutput, SystemResources, BadPathName, FileBusy, SymLinkLoop, ReadOnlyFileSystem, /// On Windows, file paths must be valid Unicode. InvalidUtf8, } || UnexpectedError; /// check user's permissions for a file /// TODO currently this assumes `mode` is `F.OK` on Windows. pub fn access(path: []const u8, mode: u32) AccessError!void { if (builtin.os.tag == .windows) { const path_w = try windows.sliceToPrefixedFileW(path); _ = try windows.GetFileAttributesW(path_w.span().ptr); return; } else if (builtin.os.tag == .wasi and !builtin.link_libc) { return faccessat(wasi.AT.FDCWD, path, mode, 0); } const path_c = try toPosixPath(path); return accessZ(&path_c, mode); } /// Same as `access` except `path` is null-terminated. pub fn accessZ(path: [*:0]const u8, mode: u32) AccessError!void { if (builtin.os.tag == .windows) { const path_w = try windows.cStrToPrefixedFileW(path); _ = try windows.GetFileAttributesW(path_w.span().ptr); return; } else if (builtin.os.tag == .wasi and !builtin.link_libc) { return access(mem.sliceTo(path, 0), mode); } switch (errno(system.access(path, mode))) { .SUCCESS => return, .ACCES => return error.PermissionDenied, .ROFS => return error.ReadOnlyFileSystem, .LOOP => return error.SymLinkLoop, .TXTBSY => return error.FileBusy, .NOTDIR => return error.FileNotFound, .NOENT => return error.FileNotFound, .NAMETOOLONG => return error.NameTooLong, .INVAL => unreachable, .FAULT => unreachable, .IO => return error.InputOutput, .NOMEM => return error.SystemResources, else => |err| return unexpectedErrno(err), } } /// Call from Windows-specific code if you already have a UTF-16LE encoded, null terminated string. /// Otherwise use `access` or `accessC`. /// TODO currently this ignores `mode`. pub fn accessW(path: [*:0]const u16, mode: u32) windows.GetFileAttributesError!void { _ = mode; const ret = try windows.GetFileAttributesW(path); if (ret != windows.INVALID_FILE_ATTRIBUTES) { return; } switch (windows.kernel32.GetLastError()) { .FILE_NOT_FOUND => return error.FileNotFound, .PATH_NOT_FOUND => return error.FileNotFound, .ACCESS_DENIED => return error.PermissionDenied, else => |err| return windows.unexpectedError(err), } } /// Check user's permissions for a file, based on an open directory handle. /// TODO currently this ignores `mode` and `flags` on Windows. pub fn faccessat(dirfd: fd_t, path: []const u8, mode: u32, flags: u32) AccessError!void { if (builtin.os.tag == .windows) { const path_w = try windows.sliceToPrefixedFileW(path); return faccessatW(dirfd, path_w.span().ptr, mode, flags); } else if (builtin.os.tag == .wasi and !builtin.link_libc) { var resolved = RelativePathWasi{ .dir_fd = dirfd, .relative_path = path }; const file = blk: { if (dirfd == wasi.AT.FDCWD or fs.path.isAbsolute(path)) { // Resolve absolute or CWD-relative paths to a path within a Preopen var path_buf: [MAX_PATH_BYTES]u8 = undefined; resolved = resolvePathWasi(path, &path_buf) catch |err| break :blk @as(FStatAtError!Stat, err); break :blk fstatat(resolved.dir_fd, resolved.relative_path, flags); } break :blk fstatat(dirfd, path, flags); } catch |err| switch (err) { error.AccessDenied => return error.PermissionDenied, else => |e| return e, }; if (mode != F_OK) { var directory: wasi.fdstat_t = undefined; if (wasi.fd_fdstat_get(resolved.dir_fd, &directory) != .SUCCESS) { return error.PermissionDenied; } var rights: wasi.rights_t = 0; if (mode & R_OK != 0) { rights |= if (file.filetype == .DIRECTORY) wasi.RIGHT.FD_READDIR else wasi.RIGHT.FD_READ; } if (mode & W_OK != 0) { rights |= wasi.RIGHT.FD_WRITE; } // No validation for X_OK if ((rights & directory.fs_rights_inheriting) != rights) { return error.PermissionDenied; } } return; } const path_c = try toPosixPath(path); return faccessatZ(dirfd, &path_c, mode, flags); } /// Same as `faccessat` except the path parameter is null-terminated. pub fn faccessatZ(dirfd: fd_t, path: [*:0]const u8, mode: u32, flags: u32) AccessError!void { if (builtin.os.tag == .windows) { const path_w = try windows.cStrToPrefixedFileW(path); return faccessatW(dirfd, path_w.span().ptr, mode, flags); } else if (builtin.os.tag == .wasi and !builtin.link_libc) { return faccessat(dirfd, mem.sliceTo(path, 0), mode, flags); } switch (errno(system.faccessat(dirfd, path, mode, flags))) { .SUCCESS => return, .ACCES => return error.PermissionDenied, .ROFS => return error.ReadOnlyFileSystem, .LOOP => return error.SymLinkLoop, .TXTBSY => return error.FileBusy, .NOTDIR => return error.FileNotFound, .NOENT => return error.FileNotFound, .NAMETOOLONG => return error.NameTooLong, .INVAL => unreachable, .FAULT => unreachable, .IO => return error.InputOutput, .NOMEM => return error.SystemResources, else => |err| return unexpectedErrno(err), } } /// Same as `faccessat` except asserts the target is Windows and the path parameter /// is NtDll-prefixed, null-terminated, WTF-16 encoded. /// TODO currently this ignores `mode` and `flags` pub fn faccessatW(dirfd: fd_t, sub_path_w: [*:0]const u16, mode: u32, flags: u32) AccessError!void { _ = mode; _ = flags; if (sub_path_w[0] == '.' and sub_path_w[1] == 0) { return; } if (sub_path_w[0] == '.' and sub_path_w[1] == '.' and sub_path_w[2] == 0) { return; } const path_len_bytes = math.cast(u16, mem.sliceTo(sub_path_w, 0).len * 2) orelse return error.NameTooLong; var nt_name = windows.UNICODE_STRING{ .Length = path_len_bytes, .MaximumLength = path_len_bytes, .Buffer = @intToPtr([*]u16, @ptrToInt(sub_path_w)), }; var attr = windows.OBJECT_ATTRIBUTES{ .Length = @sizeOf(windows.OBJECT_ATTRIBUTES), .RootDirectory = if (std.fs.path.isAbsoluteWindowsW(sub_path_w)) null else dirfd, .Attributes = 0, // Note we do not use OBJ_CASE_INSENSITIVE here. .ObjectName = &nt_name, .SecurityDescriptor = null, .SecurityQualityOfService = null, }; var basic_info: windows.FILE_BASIC_INFORMATION = undefined; switch (windows.ntdll.NtQueryAttributesFile(&attr, &basic_info)) { .SUCCESS => return, .OBJECT_NAME_NOT_FOUND => return error.FileNotFound, .OBJECT_PATH_NOT_FOUND => return error.FileNotFound, .OBJECT_NAME_INVALID => unreachable, .INVALID_PARAMETER => unreachable, .ACCESS_DENIED => return error.PermissionDenied, .OBJECT_PATH_SYNTAX_BAD => unreachable, else => |rc| return windows.unexpectedStatus(rc), } } pub const PipeError = error{ SystemFdQuotaExceeded, ProcessFdQuotaExceeded, } || UnexpectedError; /// Creates a unidirectional data channel that can be used for interprocess communication. pub fn pipe() PipeError![2]fd_t { var fds: [2]fd_t = undefined; switch (errno(system.pipe(&fds))) { .SUCCESS => return fds, .INVAL => unreachable, // Invalid parameters to pipe() .FAULT => unreachable, // Invalid fds pointer .NFILE => return error.SystemFdQuotaExceeded, .MFILE => return error.ProcessFdQuotaExceeded, else => |err| return unexpectedErrno(err), } } pub fn pipe2(flags: u32) PipeError![2]fd_t { if (@hasDecl(system, "pipe2")) { var fds: [2]fd_t = undefined; switch (errno(system.pipe2(&fds, flags))) { .SUCCESS => return fds, .INVAL => unreachable, // Invalid flags .FAULT => unreachable, // Invalid fds pointer .NFILE => return error.SystemFdQuotaExceeded, .MFILE => return error.ProcessFdQuotaExceeded, else => |err| return unexpectedErrno(err), } } var fds: [2]fd_t = try pipe(); errdefer { close(fds[0]); close(fds[1]); } if (flags == 0) return fds; // O.CLOEXEC is special, it's a file descriptor flag and must be set using // F.SETFD. if (flags & O.CLOEXEC != 0) { for (fds) |fd| { switch (errno(system.fcntl(fd, F.SETFD, @as(u32, FD_CLOEXEC)))) { .SUCCESS => {}, .INVAL => unreachable, // Invalid flags .BADF => unreachable, // Always a race condition else => |err| return unexpectedErrno(err), } } } const new_flags = flags & ~@as(u32, O.CLOEXEC); // Set every other flag affecting the file status using F.SETFL. if (new_flags != 0) { for (fds) |fd| { switch (errno(system.fcntl(fd, F.SETFL, new_flags))) { .SUCCESS => {}, .INVAL => unreachable, // Invalid flags .BADF => unreachable, // Always a race condition else => |err| return unexpectedErrno(err), } } } return fds; } pub const SysCtlError = error{ PermissionDenied, SystemResources, NameTooLong, UnknownName, } || UnexpectedError; pub fn sysctl( name: []const c_int, oldp: ?*anyopaque, oldlenp: ?*usize, newp: ?*anyopaque, newlen: usize, ) SysCtlError!void { if (builtin.os.tag == .wasi) { @panic("unsupported"); // TODO should be compile error, not panic } if (builtin.os.tag == .haiku) { @panic("unsupported"); // TODO should be compile error, not panic } const name_len = math.cast(c_uint, name.len) orelse return error.NameTooLong; switch (errno(system.sysctl(name.ptr, name_len, oldp, oldlenp, newp, newlen))) { .SUCCESS => return, .FAULT => unreachable, .PERM => return error.PermissionDenied, .NOMEM => return error.SystemResources, .NOENT => return error.UnknownName, else => |err| return unexpectedErrno(err), } } pub fn sysctlbynameZ( name: [*:0]const u8, oldp: ?*anyopaque, oldlenp: ?*usize, newp: ?*anyopaque, newlen: usize, ) SysCtlError!void { if (builtin.os.tag == .wasi) { @panic("unsupported"); // TODO should be compile error, not panic } if (builtin.os.tag == .haiku) { @panic("unsupported"); // TODO should be compile error, not panic } switch (errno(system.sysctlbyname(name, oldp, oldlenp, newp, newlen))) { .SUCCESS => return, .FAULT => unreachable, .PERM => return error.PermissionDenied, .NOMEM => return error.SystemResources, .NOENT => return error.UnknownName, else => |err| return unexpectedErrno(err), } } pub fn gettimeofday(tv: ?*timeval, tz: ?*timezone) void { switch (errno(system.gettimeofday(tv, tz))) { .SUCCESS => return, .INVAL => unreachable, else => unreachable, } } pub const SeekError = error{ Unseekable, /// In WASI, this error may occur when the file descriptor does /// not hold the required rights to seek on it. AccessDenied, } || UnexpectedError; /// Repositions read/write file offset relative to the beginning. pub fn lseek_SET(fd: fd_t, offset: u64) SeekError!void { if (builtin.os.tag == .linux and !builtin.link_libc and @sizeOf(usize) == 4) { var result: u64 = undefined; switch (errno(system.llseek(fd, offset, &result, SEEK.SET))) { .SUCCESS => return, .BADF => unreachable, // always a race condition .INVAL => return error.Unseekable, .OVERFLOW => return error.Unseekable, .SPIPE => return error.Unseekable, .NXIO => return error.Unseekable, else => |err| return unexpectedErrno(err), } } if (builtin.os.tag == .windows) { return windows.SetFilePointerEx_BEGIN(fd, offset); } if (builtin.os.tag == .wasi and !builtin.link_libc) { var new_offset: wasi.filesize_t = undefined; switch (wasi.fd_seek(fd, @bitCast(wasi.filedelta_t, offset), .SET, &new_offset)) { .SUCCESS => return, .BADF => unreachable, // always a race condition .INVAL => return error.Unseekable, .OVERFLOW => return error.Unseekable, .SPIPE => return error.Unseekable, .NXIO => return error.Unseekable, .NOTCAPABLE => return error.AccessDenied, else => |err| return unexpectedErrno(err), } } const lseek_sym = if (builtin.os.tag == .linux and builtin.link_libc) system.lseek64 else system.lseek; const ioffset = @bitCast(i64, offset); // the OS treats this as unsigned switch (errno(lseek_sym(fd, ioffset, SEEK.SET))) { .SUCCESS => return, .BADF => unreachable, // always a race condition .INVAL => return error.Unseekable, .OVERFLOW => return error.Unseekable, .SPIPE => return error.Unseekable, .NXIO => return error.Unseekable, else => |err| return unexpectedErrno(err), } } /// Repositions read/write file offset relative to the current offset. pub fn lseek_CUR(fd: fd_t, offset: i64) SeekError!void { if (builtin.os.tag == .linux and !builtin.link_libc and @sizeOf(usize) == 4) { var result: u64 = undefined; switch (errno(system.llseek(fd, @bitCast(u64, offset), &result, SEEK.CUR))) { .SUCCESS => return, .BADF => unreachable, // always a race condition .INVAL => return error.Unseekable, .OVERFLOW => return error.Unseekable, .SPIPE => return error.Unseekable, .NXIO => return error.Unseekable, else => |err| return unexpectedErrno(err), } } if (builtin.os.tag == .windows) { return windows.SetFilePointerEx_CURRENT(fd, offset); } if (builtin.os.tag == .wasi and !builtin.link_libc) { var new_offset: wasi.filesize_t = undefined; switch (wasi.fd_seek(fd, offset, .CUR, &new_offset)) { .SUCCESS => return, .BADF => unreachable, // always a race condition .INVAL => return error.Unseekable, .OVERFLOW => return error.Unseekable, .SPIPE => return error.Unseekable, .NXIO => return error.Unseekable, .NOTCAPABLE => return error.AccessDenied, else => |err| return unexpectedErrno(err), } } const lseek_sym = if (builtin.os.tag == .linux and builtin.link_libc) system.lseek64 else system.lseek; const ioffset = @bitCast(i64, offset); // the OS treats this as unsigned switch (errno(lseek_sym(fd, ioffset, SEEK.CUR))) { .SUCCESS => return, .BADF => unreachable, // always a race condition .INVAL => return error.Unseekable, .OVERFLOW => return error.Unseekable, .SPIPE => return error.Unseekable, .NXIO => return error.Unseekable, else => |err| return unexpectedErrno(err), } } /// Repositions read/write file offset relative to the end. pub fn lseek_END(fd: fd_t, offset: i64) SeekError!void { if (builtin.os.tag == .linux and !builtin.link_libc and @sizeOf(usize) == 4) { var result: u64 = undefined; switch (errno(system.llseek(fd, @bitCast(u64, offset), &result, SEEK.END))) { .SUCCESS => return, .BADF => unreachable, // always a race condition .INVAL => return error.Unseekable, .OVERFLOW => return error.Unseekable, .SPIPE => return error.Unseekable, .NXIO => return error.Unseekable, else => |err| return unexpectedErrno(err), } } if (builtin.os.tag == .windows) { return windows.SetFilePointerEx_END(fd, offset); } if (builtin.os.tag == .wasi and !builtin.link_libc) { var new_offset: wasi.filesize_t = undefined; switch (wasi.fd_seek(fd, offset, .END, &new_offset)) { .SUCCESS => return, .BADF => unreachable, // always a race condition .INVAL => return error.Unseekable, .OVERFLOW => return error.Unseekable, .SPIPE => return error.Unseekable, .NXIO => return error.Unseekable, .NOTCAPABLE => return error.AccessDenied, else => |err| return unexpectedErrno(err), } } const lseek_sym = if (builtin.os.tag == .linux and builtin.link_libc) system.lseek64 else system.lseek; const ioffset = @bitCast(i64, offset); // the OS treats this as unsigned switch (errno(lseek_sym(fd, ioffset, SEEK.END))) { .SUCCESS => return, .BADF => unreachable, // always a race condition .INVAL => return error.Unseekable, .OVERFLOW => return error.Unseekable, .SPIPE => return error.Unseekable, .NXIO => return error.Unseekable, else => |err| return unexpectedErrno(err), } } /// Returns the read/write file offset relative to the beginning. pub fn lseek_CUR_get(fd: fd_t) SeekError!u64 { if (builtin.os.tag == .linux and !builtin.link_libc and @sizeOf(usize) == 4) { var result: u64 = undefined; switch (errno(system.llseek(fd, 0, &result, SEEK.CUR))) { .SUCCESS => return result, .BADF => unreachable, // always a race condition .INVAL => return error.Unseekable, .OVERFLOW => return error.Unseekable, .SPIPE => return error.Unseekable, .NXIO => return error.Unseekable, else => |err| return unexpectedErrno(err), } } if (builtin.os.tag == .windows) { return windows.SetFilePointerEx_CURRENT_get(fd); } if (builtin.os.tag == .wasi and !builtin.link_libc) { var new_offset: wasi.filesize_t = undefined; switch (wasi.fd_seek(fd, 0, .CUR, &new_offset)) { .SUCCESS => return new_offset, .BADF => unreachable, // always a race condition .INVAL => return error.Unseekable, .OVERFLOW => return error.Unseekable, .SPIPE => return error.Unseekable, .NXIO => return error.Unseekable, .NOTCAPABLE => return error.AccessDenied, else => |err| return unexpectedErrno(err), } } const lseek_sym = if (builtin.os.tag == .linux and builtin.link_libc) system.lseek64 else system.lseek; const rc = lseek_sym(fd, 0, SEEK.CUR); switch (errno(rc)) { .SUCCESS => return @bitCast(u64, rc), .BADF => unreachable, // always a race condition .INVAL => return error.Unseekable, .OVERFLOW => return error.Unseekable, .SPIPE => return error.Unseekable, .NXIO => return error.Unseekable, else => |err| return unexpectedErrno(err), } } pub const FcntlError = error{ PermissionDenied, FileBusy, ProcessFdQuotaExceeded, Locked, DeadLock, LockedRegionLimitExceeded, } || UnexpectedError; pub fn fcntl(fd: fd_t, cmd: i32, arg: usize) FcntlError!usize { while (true) { const rc = system.fcntl(fd, cmd, arg); switch (errno(rc)) { .SUCCESS => return @intCast(usize, rc), .INTR => continue, .AGAIN, .ACCES => return error.Locked, .BADF => unreachable, .BUSY => return error.FileBusy, .INVAL => unreachable, // invalid parameters .PERM => return error.PermissionDenied, .MFILE => return error.ProcessFdQuotaExceeded, .NOTDIR => unreachable, // invalid parameter .DEADLK => return error.DeadLock, .NOLCK => return error.LockedRegionLimitExceeded, else => |err| return unexpectedErrno(err), } } } fn setSockFlags(sock: socket_t, flags: u32) !void { if ((flags & SOCK.CLOEXEC) != 0) { if (builtin.os.tag == .windows) { // TODO: Find out if this is supported for sockets } else { var fd_flags = fcntl(sock, F.GETFD, 0) catch |err| switch (err) { error.FileBusy => unreachable, error.Locked => unreachable, error.PermissionDenied => unreachable, error.DeadLock => unreachable, error.LockedRegionLimitExceeded => unreachable, else => |e| return e, }; fd_flags |= FD_CLOEXEC; _ = fcntl(sock, F.SETFD, fd_flags) catch |err| switch (err) { error.FileBusy => unreachable, error.Locked => unreachable, error.PermissionDenied => unreachable, error.DeadLock => unreachable, error.LockedRegionLimitExceeded => unreachable, else => |e| return e, }; } } if ((flags & SOCK.NONBLOCK) != 0) { if (builtin.os.tag == .windows) { var mode: c_ulong = 1; if (windows.ws2_32.ioctlsocket(sock, windows.ws2_32.FIONBIO, &mode) == windows.ws2_32.SOCKET_ERROR) { switch (windows.ws2_32.WSAGetLastError()) { .WSANOTINITIALISED => unreachable, .WSAENETDOWN => return error.NetworkSubsystemFailed, .WSAENOTSOCK => return error.FileDescriptorNotASocket, // TODO: handle more errors else => |err| return windows.unexpectedWSAError(err), } } } else { var fl_flags = fcntl(sock, F.GETFL, 0) catch |err| switch (err) { error.FileBusy => unreachable, error.Locked => unreachable, error.PermissionDenied => unreachable, error.DeadLock => unreachable, error.LockedRegionLimitExceeded => unreachable, else => |e| return e, }; fl_flags |= O.NONBLOCK; _ = fcntl(sock, F.SETFL, fl_flags) catch |err| switch (err) { error.FileBusy => unreachable, error.Locked => unreachable, error.PermissionDenied => unreachable, error.DeadLock => unreachable, error.LockedRegionLimitExceeded => unreachable, else => |e| return e, }; } } } pub const FlockError = error{ WouldBlock, /// The kernel ran out of memory for allocating file locks SystemResources, /// The underlying filesystem does not support file locks FileLocksNotSupported, } || UnexpectedError; /// Depending on the operating system `flock` may or may not interact with /// `fcntl` locks made by other processes. pub fn flock(fd: fd_t, operation: i32) FlockError!void { while (true) { const rc = system.flock(fd, operation); switch (errno(rc)) { .SUCCESS => return, .BADF => unreachable, .INTR => continue, .INVAL => unreachable, // invalid parameters .NOLCK => return error.SystemResources, .AGAIN => return error.WouldBlock, // TODO: integrate with async instead of just returning an error .OPNOTSUPP => return error.FileLocksNotSupported, else => |err| return unexpectedErrno(err), } } } pub const RealPathError = error{ FileNotFound, AccessDenied, NameTooLong, NotSupported, NotDir, SymLinkLoop, InputOutput, FileTooBig, IsDir, ProcessFdQuotaExceeded, SystemFdQuotaExceeded, NoDevice, SystemResources, NoSpaceLeft, FileSystem, BadPathName, DeviceBusy, SharingViolation, PipeBusy, /// On WASI, the current CWD may not be associated with an absolute path. InvalidHandle, /// On Windows, file paths must be valid Unicode. InvalidUtf8, PathAlreadyExists, } || UnexpectedError; /// Return the canonicalized absolute pathname. /// Expands all symbolic links and resolves references to `.`, `..`, and /// extra `/` characters in `pathname`. /// The return value is a slice of `out_buffer`, but not necessarily from the beginning. /// See also `realpathZ` and `realpathW`. pub fn realpath(pathname: []const u8, out_buffer: *[MAX_PATH_BYTES]u8) RealPathError![]u8 { if (builtin.os.tag == .windows) { const pathname_w = try windows.sliceToPrefixedFileW(pathname); return realpathW(pathname_w.span(), out_buffer); } else if (builtin.os.tag == .wasi and !builtin.link_libc) { var alloc = std.heap.FixedBufferAllocator.init(out_buffer); // NOTE: This emulation is incomplete. Symbolic links are not // currently expanded during path canonicalization. const paths = &.{ wasi_cwd.cwd, pathname }; return fs.path.resolve(alloc.allocator(), paths) catch error.NameTooLong; } const pathname_c = try toPosixPath(pathname); return realpathZ(&pathname_c, out_buffer); } /// Same as `realpath` except `pathname` is null-terminated. pub fn realpathZ(pathname: [*:0]const u8, out_buffer: *[MAX_PATH_BYTES]u8) RealPathError![]u8 { if (builtin.os.tag == .windows) { const pathname_w = try windows.cStrToPrefixedFileW(pathname); return realpathW(pathname_w.span(), out_buffer); } else if (builtin.os.tag == .wasi and !builtin.link_libc) { return realpath(mem.sliceTo(pathname, 0), out_buffer); } if (!builtin.link_libc) { const flags = if (builtin.os.tag == .linux) O.PATH | O.NONBLOCK | O.CLOEXEC else O.NONBLOCK | O.CLOEXEC; const fd = openZ(pathname, flags, 0) catch |err| switch (err) { error.FileLocksNotSupported => unreachable, error.WouldBlock => unreachable, error.FileBusy => unreachable, // not asking for write permissions error.InvalidHandle => unreachable, // WASI-only else => |e| return e, }; defer close(fd); return getFdPath(fd, out_buffer); } const result_path = std.c.realpath(pathname, out_buffer) orelse switch (@intToEnum(E, std.c._errno().*)) { .SUCCESS => unreachable, .INVAL => unreachable, .BADF => unreachable, .FAULT => unreachable, .ACCES => return error.AccessDenied, .NOENT => return error.FileNotFound, .OPNOTSUPP => return error.NotSupported, .NOTDIR => return error.NotDir, .NAMETOOLONG => return error.NameTooLong, .LOOP => return error.SymLinkLoop, .IO => return error.InputOutput, else => |err| return unexpectedErrno(err), }; return mem.sliceTo(result_path, 0); } /// Same as `realpath` except `pathname` is UTF16LE-encoded. pub fn realpathW(pathname: []const u16, out_buffer: *[MAX_PATH_BYTES]u8) RealPathError![]u8 { const w = windows; const dir = std.fs.cwd().fd; const access_mask = w.GENERIC_READ | w.SYNCHRONIZE; const share_access = w.FILE_SHARE_READ; const creation = w.FILE_OPEN; const h_file = blk: { const res = w.OpenFile(pathname, .{ .dir = dir, .access_mask = access_mask, .share_access = share_access, .creation = creation, .io_mode = .blocking, }) catch |err| switch (err) { error.IsDir => break :blk w.OpenFile(pathname, .{ .dir = dir, .access_mask = access_mask, .share_access = share_access, .creation = creation, .io_mode = .blocking, .filter = .dir_only, }) catch |er| switch (er) { error.WouldBlock => unreachable, else => |e2| return e2, }, error.WouldBlock => unreachable, else => |e| return e, }; break :blk res; }; defer w.CloseHandle(h_file); return getFdPath(h_file, out_buffer); } /// Return canonical path of handle `fd`. /// This function is very host-specific and is not universally supported by all hosts. /// For example, while it generally works on Linux, macOS, FreeBSD or Windows, it is /// unsupported on WASI. pub fn getFdPath(fd: fd_t, out_buffer: *[MAX_PATH_BYTES]u8) RealPathError![]u8 { switch (builtin.os.tag) { .windows => { var wide_buf: [windows.PATH_MAX_WIDE]u16 = undefined; const wide_slice = try windows.GetFinalPathNameByHandle(fd, .{}, wide_buf[0..]); // Trust that Windows gives us valid UTF-16LE. const end_index = std.unicode.utf16leToUtf8(out_buffer, wide_slice) catch unreachable; return out_buffer[0..end_index]; }, .macos, .ios, .watchos, .tvos => { // On macOS, we can use F.GETPATH fcntl command to query the OS for // the path to the file descriptor. @memset(out_buffer, 0, MAX_PATH_BYTES); switch (errno(system.fcntl(fd, F.GETPATH, out_buffer))) { .SUCCESS => {}, .BADF => return error.FileNotFound, // TODO man pages for fcntl on macOS don't really tell you what // errno values to expect when command is F.GETPATH... else => |err| return unexpectedErrno(err), } const len = mem.indexOfScalar(u8, out_buffer[0..], @as(u8, 0)) orelse MAX_PATH_BYTES; return out_buffer[0..len]; }, .linux => { var procfs_buf: ["/proc/self/fd/-2147483648".len:0]u8 = undefined; const proc_path = std.fmt.bufPrint(procfs_buf[0..], "/proc/self/fd/{d}\x00", .{fd}) catch unreachable; const target = readlinkZ(std.meta.assumeSentinel(proc_path.ptr, 0), out_buffer) catch |err| { switch (err) { error.UnsupportedReparsePointType => unreachable, // Windows only, error.NotLink => unreachable, else => |e| return e, } }; return target; }, .solaris => { var procfs_buf: ["/proc/self/path/-2147483648".len:0]u8 = undefined; const proc_path = std.fmt.bufPrintZ(procfs_buf[0..], "/proc/self/path/{d}", .{fd}) catch unreachable; const target = readlinkZ(proc_path, out_buffer) catch |err| switch (err) { error.UnsupportedReparsePointType => unreachable, error.NotLink => unreachable, else => |e| return e, }; return target; }, .freebsd => { comptime if (builtin.os.version_range.semver.max.order(.{ .major = 13, .minor = 0 }) == .lt) @compileError("querying for canonical path of a handle is unsupported on FreeBSD 12 and below"); var kfile: system.kinfo_file = undefined; kfile.structsize = system.KINFO_FILE_SIZE; switch (errno(system.fcntl(fd, system.F.KINFO, @ptrToInt(&kfile)))) { .SUCCESS => {}, .BADF => return error.FileNotFound, else => |err| return unexpectedErrno(err), } const len = mem.indexOfScalar(u8, &kfile.path, 0) orelse MAX_PATH_BYTES; mem.copy(u8, out_buffer, kfile.path[0..len]); return out_buffer[0..len]; }, else => @compileError("querying for canonical path of a handle is unsupported on this host"), } } /// Spurious wakeups are possible and no precision of timing is guaranteed. pub fn nanosleep(seconds: u64, nanoseconds: u64) void { var req = timespec{ .tv_sec = math.cast(isize, seconds) orelse math.maxInt(isize), .tv_nsec = math.cast(isize, nanoseconds) orelse math.maxInt(isize), }; var rem: timespec = undefined; while (true) { switch (errno(system.nanosleep(&req, &rem))) { .FAULT => unreachable, .INVAL => { // Sometimes Darwin returns EINVAL for no reason. // We treat it as a spurious wakeup. return; }, .INTR => { req = rem; continue; }, // This prong handles success as well as unexpected errors. else => return, } } } pub fn dl_iterate_phdr( context: anytype, comptime Error: type, comptime callback: fn (info: *dl_phdr_info, size: usize, context: @TypeOf(context)) Error!void, ) Error!void { const Context = @TypeOf(context); if (builtin.object_format != .elf) @compileError("dl_iterate_phdr is not available for this target"); if (builtin.link_libc) { switch (system.dl_iterate_phdr(struct { fn callbackC(info: *dl_phdr_info, size: usize, data: ?*anyopaque) callconv(.C) c_int { const context_ptr = @ptrCast(*const Context, @alignCast(@alignOf(*const Context), data)); callback(info, size, context_ptr.*) catch |err| return @errorToInt(err); return 0; } }.callbackC, @intToPtr(?*anyopaque, @ptrToInt(&context)))) { 0 => return, else => |err| return @errSetCast(Error, @intToError(@intCast(u16, err))), // TODO don't hardcode u16 } } const elf_base = std.process.getBaseAddress(); const ehdr = @intToPtr(*elf.Ehdr, elf_base); // Make sure the base address points to an ELF image. assert(mem.eql(u8, ehdr.e_ident[0..4], elf.MAGIC)); const n_phdr = ehdr.e_phnum; const phdrs = (@intToPtr([*]elf.Phdr, elf_base + ehdr.e_phoff))[0..n_phdr]; var it = dl.linkmap_iterator(phdrs) catch unreachable; // The executable has no dynamic link segment, create a single entry for // the whole ELF image. if (it.end()) { // Find the base address for the ELF image, if this is a PIE the value // is non-zero. const base_address = for (phdrs) |*phdr| { if (phdr.p_type == elf.PT_PHDR) { break @ptrToInt(phdrs.ptr) - phdr.p_vaddr; // We could try computing the difference between _DYNAMIC and // the p_vaddr of the PT_DYNAMIC section, but using the phdr is // good enough (Is it?). } } else unreachable; var info = dl_phdr_info{ .dlpi_addr = base_address, .dlpi_name = "/proc/self/exe", .dlpi_phdr = phdrs.ptr, .dlpi_phnum = ehdr.e_phnum, }; return callback(&info, @sizeOf(dl_phdr_info), context); } // Last return value from the callback function. while (it.next()) |entry| { var dlpi_phdr: [*]elf.Phdr = undefined; var dlpi_phnum: u16 = undefined; if (entry.l_addr != 0) { const elf_header = @intToPtr(*elf.Ehdr, entry.l_addr); dlpi_phdr = @intToPtr([*]elf.Phdr, entry.l_addr + elf_header.e_phoff); dlpi_phnum = elf_header.e_phnum; } else { // This is the running ELF image dlpi_phdr = @intToPtr([*]elf.Phdr, elf_base + ehdr.e_phoff); dlpi_phnum = ehdr.e_phnum; } var info = dl_phdr_info{ .dlpi_addr = entry.l_addr, .dlpi_name = entry.l_name, .dlpi_phdr = dlpi_phdr, .dlpi_phnum = dlpi_phnum, }; try callback(&info, @sizeOf(dl_phdr_info), context); } } pub const ClockGetTimeError = error{UnsupportedClock} || UnexpectedError; /// TODO: change this to return the timespec as a return value /// TODO: look into making clk_id an enum pub fn clock_gettime(clk_id: i32, tp: *timespec) ClockGetTimeError!void { if (builtin.os.tag == .wasi and !builtin.link_libc) { var ts: timestamp_t = undefined; switch (system.clock_time_get(@bitCast(u32, clk_id), 1, &ts)) { .SUCCESS => { tp.* = .{ .tv_sec = @intCast(i64, ts / std.time.ns_per_s), .tv_nsec = @intCast(isize, ts % std.time.ns_per_s), }; }, .INVAL => return error.UnsupportedClock, else => |err| return unexpectedErrno(err), } return; } if (builtin.os.tag == .windows) { if (clk_id == CLOCK.REALTIME) { var ft: windows.FILETIME = undefined; windows.kernel32.GetSystemTimeAsFileTime(&ft); // FileTime has a granularity of 100 nanoseconds and uses the NTFS/Windows epoch. const ft64 = (@as(u64, ft.dwHighDateTime) << 32) | ft.dwLowDateTime; const ft_per_s = std.time.ns_per_s / 100; tp.* = .{ .tv_sec = @intCast(i64, ft64 / ft_per_s) + std.time.epoch.windows, .tv_nsec = @intCast(c_long, ft64 % ft_per_s) * 100, }; return; } else { // TODO POSIX implementation of CLOCK.MONOTONIC on Windows. return error.UnsupportedClock; } } switch (errno(system.clock_gettime(clk_id, tp))) { .SUCCESS => return, .FAULT => unreachable, .INVAL => return error.UnsupportedClock, else => |err| return unexpectedErrno(err), } } pub fn clock_getres(clk_id: i32, res: *timespec) ClockGetTimeError!void { if (builtin.os.tag == .wasi and !builtin.link_libc) { var ts: timestamp_t = undefined; switch (system.clock_res_get(@bitCast(u32, clk_id), &ts)) { .SUCCESS => res.* = .{ .tv_sec = @intCast(i64, ts / std.time.ns_per_s), .tv_nsec = @intCast(isize, ts % std.time.ns_per_s), }, .INVAL => return error.UnsupportedClock, else => |err| return unexpectedErrno(err), } return; } switch (errno(system.clock_getres(clk_id, res))) { .SUCCESS => return, .FAULT => unreachable, .INVAL => return error.UnsupportedClock, else => |err| return unexpectedErrno(err), } } pub const SchedGetAffinityError = error{PermissionDenied} || UnexpectedError; pub fn sched_getaffinity(pid: pid_t) SchedGetAffinityError!cpu_set_t { var set: cpu_set_t = undefined; switch (errno(system.sched_getaffinity(pid, @sizeOf(cpu_set_t), &set))) { .SUCCESS => return set, .FAULT => unreachable, .INVAL => unreachable, .SRCH => unreachable, .PERM => return error.PermissionDenied, else => |err| return unexpectedErrno(err), } } /// Used to convert a slice to a null terminated slice on the stack. /// TODO https://github.com/ziglang/zig/issues/287 pub fn toPosixPath(file_path: []const u8) ![MAX_PATH_BYTES - 1:0]u8 { if (std.debug.runtime_safety) assert(std.mem.indexOfScalar(u8, file_path, 0) == null); var path_with_null: [MAX_PATH_BYTES - 1:0]u8 = undefined; // >= rather than > to make room for the null byte if (file_path.len >= MAX_PATH_BYTES) return error.NameTooLong; mem.copy(u8, &path_with_null, file_path); path_with_null[file_path.len] = 0; return path_with_null; } /// Whether or not error.Unexpected will print its value and a stack trace. /// if this happens the fix is to add the error code to the corresponding /// switch expression, possibly introduce a new error in the error set, and /// send a patch to Zig. pub const unexpected_error_tracing = (builtin.zig_backend == .stage1 or builtin.zig_backend == .stage2_llvm) and builtin.mode == .Debug; pub const UnexpectedError = error{ /// The Operating System returned an undocumented error code. /// This error is in theory not possible, but it would be better /// to handle this error than to invoke undefined behavior. Unexpected, }; /// Call this when you made a syscall or something that sets errno /// and you get an unexpected error. pub fn unexpectedErrno(err: E) UnexpectedError { if (unexpected_error_tracing) { std.debug.print("unexpected errno: {d}\n", .{@enumToInt(err)}); std.debug.dumpCurrentStackTrace(null); } return error.Unexpected; } pub const SigaltstackError = error{ /// The supplied stack size was less than MINSIGSTKSZ. SizeTooSmall, /// Attempted to change the signal stack while it was active. PermissionDenied, } || UnexpectedError; pub fn sigaltstack(ss: ?*stack_t, old_ss: ?*stack_t) SigaltstackError!void { switch (errno(system.sigaltstack(ss, old_ss))) { .SUCCESS => return, .FAULT => unreachable, .INVAL => unreachable, .NOMEM => return error.SizeTooSmall, .PERM => return error.PermissionDenied, else => |err| return unexpectedErrno(err), } } /// Examine and change a signal action. pub fn sigaction(sig: u6, noalias act: ?*const Sigaction, noalias oact: ?*Sigaction) error{OperationNotSupported}!void { switch (errno(system.sigaction(sig, act, oact))) { .SUCCESS => return, .INVAL, .NOSYS => return error.OperationNotSupported, else => unreachable, } } /// Sets the thread signal mask. pub fn sigprocmask(flags: u32, noalias set: ?*const sigset_t, noalias oldset: ?*sigset_t) void { switch (errno(system.sigprocmask(flags, set, oldset))) { .SUCCESS => return, .FAULT => unreachable, .INVAL => unreachable, else => unreachable, } } pub const FutimensError = error{ /// times is NULL, or both tv_nsec values are UTIME_NOW, and either: /// * the effective user ID of the caller does not match the owner /// of the file, the caller does not have write access to the /// file, and the caller is not privileged (Linux: does not have /// either the CAP_FOWNER or the CAP_DAC_OVERRIDE capability); /// or, /// * the file is marked immutable (see chattr(1)). AccessDenied, /// The caller attempted to change one or both timestamps to a value /// other than the current time, or to change one of the timestamps /// to the current time while leaving the other timestamp unchanged, /// (i.e., times is not NULL, neither tv_nsec field is UTIME_NOW, /// and neither tv_nsec field is UTIME_OMIT) and either: /// * the caller's effective user ID does not match the owner of /// file, and the caller is not privileged (Linux: does not have /// the CAP_FOWNER capability); or, /// * the file is marked append-only or immutable (see chattr(1)). PermissionDenied, ReadOnlyFileSystem, } || UnexpectedError; pub fn futimens(fd: fd_t, times: *const [2]timespec) FutimensError!void { if (builtin.os.tag == .wasi and !builtin.link_libc) { // TODO WASI encodes `wasi.fstflags` to signify magic values // similar to UTIME_NOW and UTIME_OMIT. Currently, we ignore // this here, but we should really handle it somehow. const atim = times[0].toTimestamp(); const mtim = times[1].toTimestamp(); switch (wasi.fd_filestat_set_times(fd, atim, mtim, wasi.FILESTAT_SET_ATIM | wasi.FILESTAT_SET_MTIM)) { .SUCCESS => return, .ACCES => return error.AccessDenied, .PERM => return error.PermissionDenied, .BADF => unreachable, // always a race condition .FAULT => unreachable, .INVAL => unreachable, .ROFS => return error.ReadOnlyFileSystem, else => |err| return unexpectedErrno(err), } } switch (errno(system.futimens(fd, times))) { .SUCCESS => return, .ACCES => return error.AccessDenied, .PERM => return error.PermissionDenied, .BADF => unreachable, // always a race condition .FAULT => unreachable, .INVAL => unreachable, .ROFS => return error.ReadOnlyFileSystem, else => |err| return unexpectedErrno(err), } } pub const GetHostNameError = error{PermissionDenied} || UnexpectedError; pub fn gethostname(name_buffer: *[HOST_NAME_MAX]u8) GetHostNameError![]u8 { if (builtin.link_libc) { switch (errno(system.gethostname(name_buffer, name_buffer.len))) { .SUCCESS => return mem.sliceTo(std.meta.assumeSentinel(name_buffer, 0), 0), .FAULT => unreachable, .NAMETOOLONG => unreachable, // HOST_NAME_MAX prevents this .PERM => return error.PermissionDenied, else => |err| return unexpectedErrno(err), } } if (builtin.os.tag == .linux) { const uts = uname(); const hostname = mem.sliceTo(std.meta.assumeSentinel(&uts.nodename, 0), 0); mem.copy(u8, name_buffer, hostname); return name_buffer[0..hostname.len]; } @compileError("TODO implement gethostname for this OS"); } pub fn uname() utsname { var uts: utsname = undefined; switch (errno(system.uname(&uts))) { .SUCCESS => return uts, .FAULT => unreachable, else => unreachable, } } pub fn res_mkquery( op: u4, dname: []const u8, class: u8, ty: u8, data: []const u8, newrr: ?[*]const u8, buf: []u8, ) usize { _ = data; _ = newrr; // This implementation is ported from musl libc. // A more idiomatic "ziggy" implementation would be welcome. var name = dname; if (mem.endsWith(u8, name, ".")) name.len -= 1; assert(name.len <= 253); const n = 17 + name.len + @boolToInt(name.len != 0); // Construct query template - ID will be filled later var q: [280]u8 = undefined; @memset(&q, 0, n); q[2] = @as(u8, op) * 8 + 1; q[5] = 1; mem.copy(u8, q[13..], name); var i: usize = 13; var j: usize = undefined; while (q[i] != 0) : (i = j + 1) { j = i; while (q[j] != 0 and q[j] != '.') : (j += 1) {} // TODO determine the circumstances for this and whether or // not this should be an error. if (j - i - 1 > 62) unreachable; q[i - 1] = @intCast(u8, j - i); } q[i + 1] = ty; q[i + 3] = class; // Make a reasonably unpredictable id var ts: timespec = undefined; clock_gettime(CLOCK.REALTIME, &ts) catch {}; const UInt = std.meta.Int(.unsigned, @bitSizeOf(@TypeOf(ts.tv_nsec))); const unsec = @bitCast(UInt, ts.tv_nsec); const id = @truncate(u32, unsec + unsec / 65536); q[0] = @truncate(u8, id / 256); q[1] = @truncate(u8, id); mem.copy(u8, buf, q[0..n]); return n; } pub const SendError = error{ /// (For UNIX domain sockets, which are identified by pathname) Write permission is denied /// on the destination socket file, or search permission is denied for one of the /// directories the path prefix. (See path_resolution(7).) /// (For UDP sockets) An attempt was made to send to a network/broadcast address as though /// it was a unicast address. AccessDenied, /// The socket is marked nonblocking and the requested operation would block, and /// there is no global event loop configured. /// It's also possible to get this error under the following condition: /// (Internet domain datagram sockets) The socket referred to by sockfd had not previously /// been bound to an address and, upon attempting to bind it to an ephemeral port, it was /// determined that all port numbers in the ephemeral port range are currently in use. See /// the discussion of /proc/sys/net/ipv4/ip_local_port_range in ip(7). WouldBlock, /// Another Fast Open is already in progress. FastOpenAlreadyInProgress, /// Connection reset by peer. ConnectionResetByPeer, /// The socket type requires that message be sent atomically, and the size of the message /// to be sent made this impossible. The message is not transmitted. MessageTooBig, /// The output queue for a network interface was full. This generally indicates that the /// interface has stopped sending, but may be caused by transient congestion. (Normally, /// this does not occur in Linux. Packets are just silently dropped when a device queue /// overflows.) /// This is also caused when there is not enough kernel memory available. SystemResources, /// The local end has been shut down on a connection oriented socket. In this case, the /// process will also receive a SIGPIPE unless MSG.NOSIGNAL is set. BrokenPipe, FileDescriptorNotASocket, /// Network is unreachable. NetworkUnreachable, /// The local network interface used to reach the destination is down. NetworkSubsystemFailed, } || UnexpectedError; pub const SendMsgError = SendError || error{ /// The passed address didn't have the correct address family in its sa_family field. AddressFamilyNotSupported, /// Returned when socket is AF.UNIX and the given path has a symlink loop. SymLinkLoop, /// Returned when socket is AF.UNIX and the given path length exceeds `MAX_PATH_BYTES` bytes. NameTooLong, /// Returned when socket is AF.UNIX and the given path does not point to an existing file. FileNotFound, NotDir, /// The socket is not connected (connection-oriented sockets only). SocketNotConnected, AddressNotAvailable, }; pub fn sendmsg( /// The file descriptor of the sending socket. sockfd: socket_t, /// Message header and iovecs msg: msghdr_const, flags: u32, ) SendMsgError!usize { while (true) { const rc = system.sendmsg(sockfd, @ptrCast(*const std.x.os.Socket.Message, &msg), @intCast(c_int, flags)); if (builtin.os.tag == .windows) { if (rc == windows.ws2_32.SOCKET_ERROR) { switch (windows.ws2_32.WSAGetLastError()) { .WSAEACCES => return error.AccessDenied, .WSAEADDRNOTAVAIL => return error.AddressNotAvailable, .WSAECONNRESET => return error.ConnectionResetByPeer, .WSAEMSGSIZE => return error.MessageTooBig, .WSAENOBUFS => return error.SystemResources, .WSAENOTSOCK => return error.FileDescriptorNotASocket, .WSAEAFNOSUPPORT => return error.AddressFamilyNotSupported, .WSAEDESTADDRREQ => unreachable, // A destination address is required. .WSAEFAULT => unreachable, // The lpBuffers, lpTo, lpOverlapped, lpNumberOfBytesSent, or lpCompletionRoutine parameters are not part of the user address space, or the lpTo parameter is too small. .WSAEHOSTUNREACH => return error.NetworkUnreachable, // TODO: WSAEINPROGRESS, WSAEINTR .WSAEINVAL => unreachable, .WSAENETDOWN => return error.NetworkSubsystemFailed, .WSAENETRESET => return error.ConnectionResetByPeer, .WSAENETUNREACH => return error.NetworkUnreachable, .WSAENOTCONN => return error.SocketNotConnected, .WSAESHUTDOWN => unreachable, // The socket has been shut down; it is not possible to WSASendTo on a socket after shutdown has been invoked with how set to SD_SEND or SD_BOTH. .WSAEWOULDBLOCK => return error.WouldBlock, .WSANOTINITIALISED => unreachable, // A successful WSAStartup call must occur before using this function. else => |err| return windows.unexpectedWSAError(err), } } else { return @intCast(usize, rc); } } else { switch (errno(rc)) { .SUCCESS => return @intCast(usize, rc), .ACCES => return error.AccessDenied, .AGAIN => return error.WouldBlock, .ALREADY => return error.FastOpenAlreadyInProgress, .BADF => unreachable, // always a race condition .CONNRESET => return error.ConnectionResetByPeer, .DESTADDRREQ => unreachable, // The socket is not connection-mode, and no peer address is set. .FAULT => unreachable, // An invalid user space address was specified for an argument. .INTR => continue, .INVAL => unreachable, // Invalid argument passed. .ISCONN => unreachable, // connection-mode socket was connected already but a recipient was specified .MSGSIZE => return error.MessageTooBig, .NOBUFS => return error.SystemResources, .NOMEM => return error.SystemResources, .NOTSOCK => unreachable, // The file descriptor sockfd does not refer to a socket. .OPNOTSUPP => unreachable, // Some bit in the flags argument is inappropriate for the socket type. .PIPE => return error.BrokenPipe, .AFNOSUPPORT => return error.AddressFamilyNotSupported, .LOOP => return error.SymLinkLoop, .NAMETOOLONG => return error.NameTooLong, .NOENT => return error.FileNotFound, .NOTDIR => return error.NotDir, .HOSTUNREACH => return error.NetworkUnreachable, .NETUNREACH => return error.NetworkUnreachable, .NOTCONN => return error.SocketNotConnected, .NETDOWN => return error.NetworkSubsystemFailed, else => |err| return unexpectedErrno(err), } } } } pub const SendToError = SendMsgError || error{ /// The destination address is not reachable by the bound address. UnreachableAddress, }; /// Transmit a message to another socket. /// /// The `sendto` call may be used only when the socket is in a connected state (so that the intended /// recipient is known). The following call /// /// send(sockfd, buf, len, flags); /// /// is equivalent to /// /// sendto(sockfd, buf, len, flags, NULL, 0); /// /// If sendto() is used on a connection-mode (`SOCK.STREAM`, `SOCK.SEQPACKET`) socket, the arguments /// `dest_addr` and `addrlen` are asserted to be `null` and `0` respectively, and asserted /// that the socket was actually connected. /// Otherwise, the address of the target is given by `dest_addr` with `addrlen` specifying its size. /// /// If the message is too long to pass atomically through the underlying protocol, /// `SendError.MessageTooBig` is returned, and the message is not transmitted. /// /// There is no indication of failure to deliver. /// /// When the message does not fit into the send buffer of the socket, `sendto` normally blocks, /// unless the socket has been placed in nonblocking I/O mode. In nonblocking mode it would fail /// with `SendError.WouldBlock`. The `select` call may be used to determine when it is /// possible to send more data. pub fn sendto( /// The file descriptor of the sending socket. sockfd: socket_t, /// Message to send. buf: []const u8, flags: u32, dest_addr: ?*const sockaddr, addrlen: socklen_t, ) SendToError!usize { while (true) { const rc = system.sendto(sockfd, buf.ptr, buf.len, flags, dest_addr, addrlen); if (builtin.os.tag == .windows) { if (rc == windows.ws2_32.SOCKET_ERROR) { switch (windows.ws2_32.WSAGetLastError()) { .WSAEACCES => return error.AccessDenied, .WSAEADDRNOTAVAIL => return error.AddressNotAvailable, .WSAECONNRESET => return error.ConnectionResetByPeer, .WSAEMSGSIZE => return error.MessageTooBig, .WSAENOBUFS => return error.SystemResources, .WSAENOTSOCK => return error.FileDescriptorNotASocket, .WSAEAFNOSUPPORT => return error.AddressFamilyNotSupported, .WSAEDESTADDRREQ => unreachable, // A destination address is required. .WSAEFAULT => unreachable, // The lpBuffers, lpTo, lpOverlapped, lpNumberOfBytesSent, or lpCompletionRoutine parameters are not part of the user address space, or the lpTo parameter is too small. .WSAEHOSTUNREACH => return error.NetworkUnreachable, // TODO: WSAEINPROGRESS, WSAEINTR .WSAEINVAL => unreachable, .WSAENETDOWN => return error.NetworkSubsystemFailed, .WSAENETRESET => return error.ConnectionResetByPeer, .WSAENETUNREACH => return error.NetworkUnreachable, .WSAENOTCONN => return error.SocketNotConnected, .WSAESHUTDOWN => unreachable, // The socket has been shut down; it is not possible to WSASendTo on a socket after shutdown has been invoked with how set to SD_SEND or SD_BOTH. .WSAEWOULDBLOCK => return error.WouldBlock, .WSANOTINITIALISED => unreachable, // A successful WSAStartup call must occur before using this function. else => |err| return windows.unexpectedWSAError(err), } } else { return @intCast(usize, rc); } } else { switch (errno(rc)) { .SUCCESS => return @intCast(usize, rc), .ACCES => return error.AccessDenied, .AGAIN => return error.WouldBlock, .ALREADY => return error.FastOpenAlreadyInProgress, .BADF => unreachable, // always a race condition .CONNRESET => return error.ConnectionResetByPeer, .DESTADDRREQ => unreachable, // The socket is not connection-mode, and no peer address is set. .FAULT => unreachable, // An invalid user space address was specified for an argument. .INTR => continue, .INVAL => return error.UnreachableAddress, .ISCONN => unreachable, // connection-mode socket was connected already but a recipient was specified .MSGSIZE => return error.MessageTooBig, .NOBUFS => return error.SystemResources, .NOMEM => return error.SystemResources, .NOTSOCK => unreachable, // The file descriptor sockfd does not refer to a socket. .OPNOTSUPP => unreachable, // Some bit in the flags argument is inappropriate for the socket type. .PIPE => return error.BrokenPipe, .AFNOSUPPORT => return error.AddressFamilyNotSupported, .LOOP => return error.SymLinkLoop, .NAMETOOLONG => return error.NameTooLong, .NOENT => return error.FileNotFound, .NOTDIR => return error.NotDir, .HOSTUNREACH => return error.NetworkUnreachable, .NETUNREACH => return error.NetworkUnreachable, .NOTCONN => return error.SocketNotConnected, .NETDOWN => return error.NetworkSubsystemFailed, else => |err| return unexpectedErrno(err), } } } } /// Transmit a message to another socket. /// /// The `send` call may be used only when the socket is in a connected state (so that the intended /// recipient is known). The only difference between `send` and `write` is the presence of /// flags. With a zero flags argument, `send` is equivalent to `write`. Also, the following /// call /// /// send(sockfd, buf, len, flags); /// /// is equivalent to /// /// sendto(sockfd, buf, len, flags, NULL, 0); /// /// There is no indication of failure to deliver. /// /// When the message does not fit into the send buffer of the socket, `send` normally blocks, /// unless the socket has been placed in nonblocking I/O mode. In nonblocking mode it would fail /// with `SendError.WouldBlock`. The `select` call may be used to determine when it is /// possible to send more data. pub fn send( /// The file descriptor of the sending socket. sockfd: socket_t, buf: []const u8, flags: u32, ) SendError!usize { return sendto(sockfd, buf, flags, null, 0) catch |err| switch (err) { error.AddressFamilyNotSupported => unreachable, error.SymLinkLoop => unreachable, error.NameTooLong => unreachable, error.FileNotFound => unreachable, error.NotDir => unreachable, error.NetworkUnreachable => unreachable, error.AddressNotAvailable => unreachable, error.SocketNotConnected => unreachable, error.UnreachableAddress => unreachable, else => |e| return e, }; } pub const SendFileError = PReadError || WriteError || SendError; fn count_iovec_bytes(iovs: []const iovec_const) usize { var count: usize = 0; for (iovs) |iov| { count += iov.iov_len; } return count; } /// Transfer data between file descriptors, with optional headers and trailers. /// Returns the number of bytes written, which can be zero. /// /// The `sendfile` call copies `in_len` bytes from one file descriptor to another. When possible, /// this is done within the operating system kernel, which can provide better performance /// characteristics than transferring data from kernel to user space and back, such as with /// `read` and `write` calls. When `in_len` is `0`, it means to copy until the end of the input file has been /// reached. Note, however, that partial writes are still possible in this case. /// /// `in_fd` must be a file descriptor opened for reading, and `out_fd` must be a file descriptor /// opened for writing. They may be any kind of file descriptor; however, if `in_fd` is not a regular /// file system file, it may cause this function to fall back to calling `read` and `write`, in which case /// atomicity guarantees no longer apply. /// /// Copying begins reading at `in_offset`. The input file descriptor seek position is ignored and not updated. /// If the output file descriptor has a seek position, it is updated as bytes are written. When /// `in_offset` is past the end of the input file, it successfully reads 0 bytes. /// /// `flags` has different meanings per operating system; refer to the respective man pages. /// /// These systems support atomically sending everything, including headers and trailers: /// * macOS /// * FreeBSD /// /// These systems support in-kernel data copying, but headers and trailers are not sent atomically: /// * Linux /// /// Other systems fall back to calling `read` / `write`. /// /// Linux has a limit on how many bytes may be transferred in one `sendfile` call, which is `0x7ffff000` /// on both 64-bit and 32-bit systems. This is due to using a signed C int as the return value, as /// well as stuffing the errno codes into the last `4096` values. This is noted on the `sendfile` man page. /// The limit on Darwin is `0x7fffffff`, trying to write more than that returns EINVAL. /// The corresponding POSIX limit on this is `math.maxInt(isize)`. pub fn sendfile( out_fd: fd_t, in_fd: fd_t, in_offset: u64, in_len: u64, headers: []const iovec_const, trailers: []const iovec_const, flags: u32, ) SendFileError!usize { var header_done = false; var total_written: usize = 0; // Prevents EOVERFLOW. const size_t = std.meta.Int(.unsigned, @typeInfo(usize).Int.bits - 1); const max_count = switch (builtin.os.tag) { .linux => 0x7ffff000, .macos, .ios, .watchos, .tvos => math.maxInt(i32), else => math.maxInt(size_t), }; switch (builtin.os.tag) { .linux => sf: { // sendfile() first appeared in Linux 2.2, glibc 2.1. const call_sf = comptime if (builtin.link_libc) std.c.versionCheck(.{ .major = 2, .minor = 1 }).ok else builtin.os.version_range.linux.range.max.order(.{ .major = 2, .minor = 2 }) != .lt; if (!call_sf) break :sf; if (headers.len != 0) { const amt = try writev(out_fd, headers); total_written += amt; if (amt < count_iovec_bytes(headers)) return total_written; header_done = true; } // Here we match BSD behavior, making a zero count value send as many bytes as possible. const adjusted_count_tmp = if (in_len == 0) max_count else @min(in_len, @as(size_t, max_count)); // TODO we should not need this cast; improve return type of @min const adjusted_count = @intCast(usize, adjusted_count_tmp); const sendfile_sym = if (builtin.link_libc) system.sendfile64 else system.sendfile; while (true) { var offset: off_t = @bitCast(off_t, in_offset); const rc = sendfile_sym(out_fd, in_fd, &offset, adjusted_count); switch (errno(rc)) { .SUCCESS => { const amt = @bitCast(usize, rc); total_written += amt; if (in_len == 0 and amt == 0) { // We have detected EOF from `in_fd`. break; } else if (amt < in_len) { return total_written; } else { break; } }, .BADF => unreachable, // Always a race condition. .FAULT => unreachable, // Segmentation fault. .OVERFLOW => unreachable, // We avoid passing too large of a `count`. .NOTCONN => unreachable, // `out_fd` is an unconnected socket. .INVAL, .NOSYS => { // EINVAL could be any of the following situations: // * Descriptor is not valid or locked // * an mmap(2)-like operation is not available for in_fd // * count is negative // * out_fd has the O.APPEND flag set // Because of the "mmap(2)-like operation" possibility, we fall back to doing read/write // manually, the same as ENOSYS. break :sf; }, .AGAIN => if (std.event.Loop.instance) |loop| { loop.waitUntilFdWritable(out_fd); continue; } else { return error.WouldBlock; }, .IO => return error.InputOutput, .PIPE => return error.BrokenPipe, .NOMEM => return error.SystemResources, .NXIO => return error.Unseekable, .SPIPE => return error.Unseekable, else => |err| { unexpectedErrno(err) catch {}; break :sf; }, } } if (trailers.len != 0) { total_written += try writev(out_fd, trailers); } return total_written; }, .freebsd => sf: { var hdtr_data: std.c.sf_hdtr = undefined; var hdtr: ?*std.c.sf_hdtr = null; if (headers.len != 0 or trailers.len != 0) { // Here we carefully avoid `@intCast` by returning partial writes when // too many io vectors are provided. const hdr_cnt = math.cast(u31, headers.len) orelse math.maxInt(u31); if (headers.len > hdr_cnt) return writev(out_fd, headers); const trl_cnt = math.cast(u31, trailers.len) orelse math.maxInt(u31); hdtr_data = std.c.sf_hdtr{ .headers = headers.ptr, .hdr_cnt = hdr_cnt, .trailers = trailers.ptr, .trl_cnt = trl_cnt, }; hdtr = &hdtr_data; } const adjusted_count = @min(in_len, max_count); while (true) { var sbytes: off_t = undefined; const offset = @bitCast(off_t, in_offset); const err = errno(system.sendfile(in_fd, out_fd, offset, adjusted_count, hdtr, &sbytes, flags)); const amt = @bitCast(usize, sbytes); switch (err) { .SUCCESS => return amt, .BADF => unreachable, // Always a race condition. .FAULT => unreachable, // Segmentation fault. .NOTCONN => unreachable, // `out_fd` is an unconnected socket. .INVAL, .OPNOTSUPP, .NOTSOCK, .NOSYS => { // EINVAL could be any of the following situations: // * The fd argument is not a regular file. // * The s argument is not a SOCK.STREAM type socket. // * The offset argument is negative. // Because of some of these possibilities, we fall back to doing read/write // manually, the same as ENOSYS. break :sf; }, .INTR => if (amt != 0) return amt else continue, .AGAIN => if (amt != 0) { return amt; } else if (std.event.Loop.instance) |loop| { loop.waitUntilFdWritable(out_fd); continue; } else { return error.WouldBlock; }, .BUSY => if (amt != 0) { return amt; } else if (std.event.Loop.instance) |loop| { loop.waitUntilFdReadable(in_fd); continue; } else { return error.WouldBlock; }, .IO => return error.InputOutput, .NOBUFS => return error.SystemResources, .PIPE => return error.BrokenPipe, else => { unexpectedErrno(err) catch {}; if (amt != 0) { return amt; } else { break :sf; } }, } } }, .macos, .ios, .tvos, .watchos => sf: { var hdtr_data: std.c.sf_hdtr = undefined; var hdtr: ?*std.c.sf_hdtr = null; if (headers.len != 0 or trailers.len != 0) { // Here we carefully avoid `@intCast` by returning partial writes when // too many io vectors are provided. const hdr_cnt = math.cast(u31, headers.len) orelse math.maxInt(u31); if (headers.len > hdr_cnt) return writev(out_fd, headers); const trl_cnt = math.cast(u31, trailers.len) orelse math.maxInt(u31); hdtr_data = std.c.sf_hdtr{ .headers = headers.ptr, .hdr_cnt = hdr_cnt, .trailers = trailers.ptr, .trl_cnt = trl_cnt, }; hdtr = &hdtr_data; } const adjusted_count_temporary = @min(in_len, @as(u63, max_count)); // TODO we should not need this int cast; improve the return type of `@min` const adjusted_count = @intCast(u63, adjusted_count_temporary); while (true) { var sbytes: off_t = adjusted_count; const signed_offset = @bitCast(i64, in_offset); const err = errno(system.sendfile(in_fd, out_fd, signed_offset, &sbytes, hdtr, flags)); const amt = @bitCast(usize, sbytes); switch (err) { .SUCCESS => return amt, .BADF => unreachable, // Always a race condition. .FAULT => unreachable, // Segmentation fault. .INVAL => unreachable, .NOTCONN => unreachable, // `out_fd` is an unconnected socket. .OPNOTSUPP, .NOTSOCK, .NOSYS => break :sf, .INTR => if (amt != 0) return amt else continue, .AGAIN => if (amt != 0) { return amt; } else if (std.event.Loop.instance) |loop| { loop.waitUntilFdWritable(out_fd); continue; } else { return error.WouldBlock; }, .IO => return error.InputOutput, .PIPE => return error.BrokenPipe, else => { unexpectedErrno(err) catch {}; if (amt != 0) { return amt; } else { break :sf; } }, } } }, else => {}, // fall back to read/write } if (headers.len != 0 and !header_done) { const amt = try writev(out_fd, headers); total_written += amt; if (amt < count_iovec_bytes(headers)) return total_written; } rw: { var buf: [8 * 4096]u8 = undefined; // Here we match BSD behavior, making a zero count value send as many bytes as possible. const adjusted_count_tmp = if (in_len == 0) buf.len else @min(buf.len, in_len); // TODO we should not need this cast; improve return type of @min const adjusted_count = @intCast(usize, adjusted_count_tmp); const amt_read = try pread(in_fd, buf[0..adjusted_count], in_offset); if (amt_read == 0) { if (in_len == 0) { // We have detected EOF from `in_fd`. break :rw; } else { return total_written; } } const amt_written = try write(out_fd, buf[0..amt_read]); total_written += amt_written; if (amt_written < in_len or in_len == 0) return total_written; } if (trailers.len != 0) { total_written += try writev(out_fd, trailers); } return total_written; } pub const CopyFileRangeError = error{ FileTooBig, InputOutput, /// `fd_in` is not open for reading; or `fd_out` is not open for writing; /// or the `O.APPEND` flag is set for `fd_out`. FilesOpenedWithWrongFlags, IsDir, OutOfMemory, NoSpaceLeft, Unseekable, PermissionDenied, SwapFile, CorruptedData, } || PReadError || PWriteError || UnexpectedError; var has_copy_file_range_syscall = std.atomic.Atomic(bool).init(true); /// Transfer data between file descriptors at specified offsets. /// Returns the number of bytes written, which can less than requested. /// /// The `copy_file_range` call copies `len` bytes from one file descriptor to another. When possible, /// this is done within the operating system kernel, which can provide better performance /// characteristics than transferring data from kernel to user space and back, such as with /// `pread` and `pwrite` calls. /// /// `fd_in` must be a file descriptor opened for reading, and `fd_out` must be a file descriptor /// opened for writing. They may be any kind of file descriptor; however, if `fd_in` is not a regular /// file system file, it may cause this function to fall back to calling `pread` and `pwrite`, in which case /// atomicity guarantees no longer apply. /// /// If `fd_in` and `fd_out` are the same, source and target ranges must not overlap. /// The file descriptor seek positions are ignored and not updated. /// When `off_in` is past the end of the input file, it successfully reads 0 bytes. /// /// `flags` has different meanings per operating system; refer to the respective man pages. /// /// These systems support in-kernel data copying: /// * Linux 4.5 (cross-filesystem 5.3) /// * FreeBSD 13.0 /// /// Other systems fall back to calling `pread` / `pwrite`. /// /// Maximum offsets on Linux and FreeBSD are `math.maxInt(i64)`. pub fn copy_file_range(fd_in: fd_t, off_in: u64, fd_out: fd_t, off_out: u64, len: usize, flags: u32) CopyFileRangeError!usize { if ((comptime builtin.os.isAtLeast(.freebsd, .{ .major = 13, .minor = 0 }) orelse false) or ((comptime builtin.os.isAtLeast(.linux, .{ .major = 4, .minor = 5 }) orelse false and std.c.versionCheck(.{ .major = 2, .minor = 27, .patch = 0 }).ok) and has_copy_file_range_syscall.load(.Monotonic))) { var off_in_copy = @bitCast(i64, off_in); var off_out_copy = @bitCast(i64, off_out); while (true) { const rc = system.copy_file_range(fd_in, &off_in_copy, fd_out, &off_out_copy, len, flags); if (builtin.os.tag == .freebsd) { switch (system.getErrno(rc)) { .SUCCESS => return @intCast(usize, rc), .BADF => return error.FilesOpenedWithWrongFlags, .FBIG => return error.FileTooBig, .IO => return error.InputOutput, .ISDIR => return error.IsDir, .NOSPC => return error.NoSpaceLeft, .INVAL => break, // these may not be regular files, try fallback .INTEGRITY => return error.CorruptedData, .INTR => continue, else => |err| return unexpectedErrno(err), } } else { // assume linux switch (system.getErrno(rc)) { .SUCCESS => return @intCast(usize, rc), .BADF => return error.FilesOpenedWithWrongFlags, .FBIG => return error.FileTooBig, .IO => return error.InputOutput, .ISDIR => return error.IsDir, .NOSPC => return error.NoSpaceLeft, .INVAL => break, // these may not be regular files, try fallback .NOMEM => return error.OutOfMemory, .OVERFLOW => return error.Unseekable, .PERM => return error.PermissionDenied, .TXTBSY => return error.SwapFile, .XDEV => break, // support for cross-filesystem copy added in Linux 5.3, use fallback .NOSYS => { // syscall added in Linux 4.5, use fallback has_copy_file_range_syscall.store(false, .Monotonic); break; }, else => |err| return unexpectedErrno(err), } } } } var buf: [8 * 4096]u8 = undefined; const adjusted_count = @min(buf.len, len); const amt_read = try pread(fd_in, buf[0..adjusted_count], off_in); // TODO without @as the line below fails to compile for wasm32-wasi: // error: integer value 0 cannot be coerced to type 'os.PWriteError!usize' if (amt_read == 0) return @as(usize, 0); return pwrite(fd_out, buf[0..amt_read], off_out); } pub const PollError = error{ /// The network subsystem has failed. NetworkSubsystemFailed, /// The kernel had no space to allocate file descriptor tables. SystemResources, } || UnexpectedError; pub fn poll(fds: []pollfd, timeout: i32) PollError!usize { while (true) { const fds_count = math.cast(nfds_t, fds.len) orelse return error.SystemResources; const rc = system.poll(fds.ptr, fds_count, timeout); if (builtin.os.tag == .windows) { if (rc == windows.ws2_32.SOCKET_ERROR) { switch (windows.ws2_32.WSAGetLastError()) { .WSANOTINITIALISED => unreachable, .WSAENETDOWN => return error.NetworkSubsystemFailed, .WSAENOBUFS => return error.SystemResources, // TODO: handle more errors else => |err| return windows.unexpectedWSAError(err), } } else { return @intCast(usize, rc); } } else { switch (errno(rc)) { .SUCCESS => return @intCast(usize, rc), .FAULT => unreachable, .INTR => continue, .INVAL => unreachable, .NOMEM => return error.SystemResources, else => |err| return unexpectedErrno(err), } } unreachable; } } pub const PPollError = error{ /// The operation was interrupted by a delivery of a signal before it could complete. SignalInterrupt, /// The kernel had no space to allocate file descriptor tables. SystemResources, } || UnexpectedError; pub fn ppoll(fds: []pollfd, timeout: ?*const timespec, mask: ?*const sigset_t) PPollError!usize { var ts: timespec = undefined; var ts_ptr: ?*timespec = null; if (timeout) |timeout_ns| { ts_ptr = &ts; ts = timeout_ns.*; } const fds_count = math.cast(nfds_t, fds.len) orelse return error.SystemResources; const rc = system.ppoll(fds.ptr, fds_count, ts_ptr, mask); switch (errno(rc)) { .SUCCESS => return @intCast(usize, rc), .FAULT => unreachable, .INTR => return error.SignalInterrupt, .INVAL => unreachable, .NOMEM => return error.SystemResources, else => |err| return unexpectedErrno(err), } } pub const RecvFromError = error{ /// The socket is marked nonblocking and the requested operation would block, and /// there is no global event loop configured. WouldBlock, /// A remote host refused to allow the network connection, typically because it is not /// running the requested service. ConnectionRefused, /// Could not allocate kernel memory. SystemResources, ConnectionResetByPeer, /// The socket has not been bound. SocketNotBound, /// The UDP message was too big for the buffer and part of it has been discarded MessageTooBig, /// The network subsystem has failed. NetworkSubsystemFailed, /// The socket is not connected (connection-oriented sockets only). SocketNotConnected, } || UnexpectedError; pub fn recv(sock: socket_t, buf: []u8, flags: u32) RecvFromError!usize { return recvfrom(sock, buf, flags, null, null); } /// If `sockfd` is opened in non blocking mode, the function will /// return error.WouldBlock when EAGAIN is received. pub fn recvfrom( sockfd: socket_t, buf: []u8, flags: u32, src_addr: ?*sockaddr, addrlen: ?*socklen_t, ) RecvFromError!usize { while (true) { const rc = system.recvfrom(sockfd, buf.ptr, buf.len, flags, src_addr, addrlen); if (builtin.os.tag == .windows) { if (rc == windows.ws2_32.SOCKET_ERROR) { switch (windows.ws2_32.WSAGetLastError()) { .WSANOTINITIALISED => unreachable, .WSAECONNRESET => return error.ConnectionResetByPeer, .WSAEINVAL => return error.SocketNotBound, .WSAEMSGSIZE => return error.MessageTooBig, .WSAENETDOWN => return error.NetworkSubsystemFailed, .WSAENOTCONN => return error.SocketNotConnected, .WSAEWOULDBLOCK => return error.WouldBlock, // TODO: handle more errors else => |err| return windows.unexpectedWSAError(err), } } else { return @intCast(usize, rc); } } else { switch (errno(rc)) { .SUCCESS => return @intCast(usize, rc), .BADF => unreachable, // always a race condition .FAULT => unreachable, .INVAL => unreachable, .NOTCONN => unreachable, .NOTSOCK => unreachable, .INTR => continue, .AGAIN => return error.WouldBlock, .NOMEM => return error.SystemResources, .CONNREFUSED => return error.ConnectionRefused, .CONNRESET => return error.ConnectionResetByPeer, else => |err| return unexpectedErrno(err), } } } } pub const DnExpandError = error{InvalidDnsPacket}; pub fn dn_expand( msg: []const u8, comp_dn: []const u8, exp_dn: []u8, ) DnExpandError!usize { // This implementation is ported from musl libc. // A more idiomatic "ziggy" implementation would be welcome. var p = comp_dn.ptr; var len: usize = std.math.maxInt(usize); const end = msg.ptr + msg.len; if (p == end or exp_dn.len == 0) return error.InvalidDnsPacket; var dest = exp_dn.ptr; const dend = dest + @min(exp_dn.len, 254); // detect reference loop using an iteration counter var i: usize = 0; while (i < msg.len) : (i += 2) { // loop invariants: p= msg.len) return error.InvalidDnsPacket; p = msg.ptr + j; } else if (p[0] != 0) { if (dest != exp_dn.ptr) { dest[0] = '.'; dest += 1; } var j = p[0]; p += 1; if (j >= @ptrToInt(end) - @ptrToInt(p) or j >= @ptrToInt(dend) - @ptrToInt(dest)) { return error.InvalidDnsPacket; } while (j != 0) { j -= 1; dest[0] = p[0]; dest += 1; p += 1; } } else { dest[0] = 0; if (len == std.math.maxInt(usize)) len = @ptrToInt(p) + 1 - @ptrToInt(comp_dn.ptr); return len; } } return error.InvalidDnsPacket; } pub const SetSockOptError = error{ /// The socket is already connected, and a specified option cannot be set while the socket is connected. AlreadyConnected, /// The option is not supported by the protocol. InvalidProtocolOption, /// The send and receive timeout values are too big to fit into the timeout fields in the socket structure. TimeoutTooBig, /// Insufficient resources are available in the system to complete the call. SystemResources, // Setting the socket option requires more elevated permissions. PermissionDenied, NetworkSubsystemFailed, FileDescriptorNotASocket, SocketNotBound, NoDevice, } || UnexpectedError; /// Set a socket's options. pub fn setsockopt(fd: socket_t, level: u32, optname: u32, opt: []const u8) SetSockOptError!void { if (builtin.os.tag == .windows) { const rc = windows.ws2_32.setsockopt(fd, @intCast(i32, level), @intCast(i32, optname), opt.ptr, @intCast(i32, opt.len)); if (rc == windows.ws2_32.SOCKET_ERROR) { switch (windows.ws2_32.WSAGetLastError()) { .WSANOTINITIALISED => unreachable, .WSAENETDOWN => return error.NetworkSubsystemFailed, .WSAEFAULT => unreachable, .WSAENOTSOCK => return error.FileDescriptorNotASocket, .WSAEINVAL => return error.SocketNotBound, else => |err| return windows.unexpectedWSAError(err), } } return; } else { switch (errno(system.setsockopt(fd, level, optname, opt.ptr, @intCast(socklen_t, opt.len)))) { .SUCCESS => {}, .BADF => unreachable, // always a race condition .NOTSOCK => unreachable, // always a race condition .INVAL => unreachable, .FAULT => unreachable, .DOM => return error.TimeoutTooBig, .ISCONN => return error.AlreadyConnected, .NOPROTOOPT => return error.InvalidProtocolOption, .NOMEM => return error.SystemResources, .NOBUFS => return error.SystemResources, .PERM => return error.PermissionDenied, .NODEV => return error.NoDevice, else => |err| return unexpectedErrno(err), } } } pub const MemFdCreateError = error{ SystemFdQuotaExceeded, ProcessFdQuotaExceeded, OutOfMemory, /// memfd_create is available in Linux 3.17 and later. This error is returned /// for older kernel versions. SystemOutdated, } || UnexpectedError; pub fn memfd_createZ(name: [*:0]const u8, flags: u32) MemFdCreateError!fd_t { switch (builtin.os.tag) { .linux => { // memfd_create is available only in glibc versions starting with 2.27. const use_c = std.c.versionCheck(.{ .major = 2, .minor = 27, .patch = 0 }).ok; const sys = if (use_c) std.c else linux; const getErrno = if (use_c) std.c.getErrno else linux.getErrno; const rc = sys.memfd_create(name, flags); switch (getErrno(rc)) { .SUCCESS => return @intCast(fd_t, rc), .FAULT => unreachable, // name has invalid memory .INVAL => unreachable, // name/flags are faulty .NFILE => return error.SystemFdQuotaExceeded, .MFILE => return error.ProcessFdQuotaExceeded, .NOMEM => return error.OutOfMemory, .NOSYS => return error.SystemOutdated, else => |err| return unexpectedErrno(err), } }, .freebsd => { const rc = system.memfd_create(name, flags); switch (errno(rc)) { .SUCCESS => return rc, .BADF => unreachable, // name argument NULL .INVAL => unreachable, // name too long or invalid/unsupported flags. .MFILE => return error.ProcessFdQuotaExceeded, .NFILE => return error.SystemFdQuotaExceeded, .NOSYS => return error.SystemOutdated, else => |err| return unexpectedErrno(err), } }, else => @compileError("target OS does not support memfd_create()"), } } pub const MFD_NAME_PREFIX = "memfd:"; pub const MFD_MAX_NAME_LEN = NAME_MAX - MFD_NAME_PREFIX.len; fn toMemFdPath(name: []const u8) ![MFD_MAX_NAME_LEN:0]u8 { var path_with_null: [MFD_MAX_NAME_LEN:0]u8 = undefined; // >= rather than > to make room for the null byte if (name.len >= MFD_MAX_NAME_LEN) return error.NameTooLong; mem.copy(u8, &path_with_null, name); path_with_null[name.len] = 0; return path_with_null; } pub fn memfd_create(name: []const u8, flags: u32) !fd_t { const name_t = try toMemFdPath(name); return memfd_createZ(&name_t, flags); } pub fn getrusage(who: i32) rusage { var result: rusage = undefined; const rc = system.getrusage(who, &result); switch (errno(rc)) { .SUCCESS => return result, .INVAL => unreachable, .FAULT => unreachable, else => unreachable, } } pub const TermiosGetError = error{NotATerminal} || UnexpectedError; pub fn tcgetattr(handle: fd_t) TermiosGetError!termios { while (true) { var term: termios = undefined; switch (errno(system.tcgetattr(handle, &term))) { .SUCCESS => return term, .INTR => continue, .BADF => unreachable, .NOTTY => return error.NotATerminal, else => |err| return unexpectedErrno(err), } } } pub const TermiosSetError = TermiosGetError || error{ProcessOrphaned}; pub fn tcsetattr(handle: fd_t, optional_action: TCSA, termios_p: termios) TermiosSetError!void { while (true) { switch (errno(system.tcsetattr(handle, optional_action, &termios_p))) { .SUCCESS => return, .BADF => unreachable, .INTR => continue, .INVAL => unreachable, .NOTTY => return error.NotATerminal, .IO => return error.ProcessOrphaned, else => |err| return unexpectedErrno(err), } } } pub const IoCtl_SIOCGIFINDEX_Error = error{ FileSystem, InterfaceNotFound, } || UnexpectedError; pub fn ioctl_SIOCGIFINDEX(fd: fd_t, ifr: *ifreq) IoCtl_SIOCGIFINDEX_Error!void { while (true) { switch (errno(system.ioctl(fd, SIOCGIFINDEX, @ptrToInt(ifr)))) { .SUCCESS => return, .INVAL => unreachable, // Bad parameters. .NOTTY => unreachable, .NXIO => unreachable, .BADF => unreachable, // Always a race condition. .FAULT => unreachable, // Bad pointer parameter. .INTR => continue, .IO => return error.FileSystem, .NODEV => return error.InterfaceNotFound, else => |err| return unexpectedErrno(err), } } } pub fn signalfd(fd: fd_t, mask: *const sigset_t, flags: u32) !fd_t { const rc = system.signalfd(fd, mask, flags); switch (errno(rc)) { .SUCCESS => return @intCast(fd_t, rc), .BADF, .INVAL => unreachable, .NFILE => return error.SystemFdQuotaExceeded, .NOMEM => return error.SystemResources, .MFILE => return error.ProcessResources, .NODEV => return error.InodeMountFail, .NOSYS => return error.SystemOutdated, else => |err| return unexpectedErrno(err), } } pub const SyncError = error{ InputOutput, NoSpaceLeft, DiskQuota, AccessDenied, } || UnexpectedError; /// Write all pending file contents and metadata modifications to all filesystems. pub fn sync() void { system.sync(); } /// Write all pending file contents and metadata modifications to the filesystem which contains the specified file. pub fn syncfs(fd: fd_t) SyncError!void { const rc = system.syncfs(fd); switch (errno(rc)) { .SUCCESS => return, .BADF, .INVAL, .ROFS => unreachable, .IO => return error.InputOutput, .NOSPC => return error.NoSpaceLeft, .DQUOT => return error.DiskQuota, else => |err| return unexpectedErrno(err), } } /// Write all pending file contents and metadata modifications for the specified file descriptor to the underlying filesystem. pub fn fsync(fd: fd_t) SyncError!void { if (builtin.os.tag == .windows) { if (windows.kernel32.FlushFileBuffers(fd) != 0) return; switch (windows.kernel32.GetLastError()) { .SUCCESS => return, .INVALID_HANDLE => unreachable, .ACCESS_DENIED => return error.AccessDenied, // a sync was performed but the system couldn't update the access time .UNEXP_NET_ERR => return error.InputOutput, else => return error.InputOutput, } } const rc = system.fsync(fd); switch (errno(rc)) { .SUCCESS => return, .BADF, .INVAL, .ROFS => unreachable, .IO => return error.InputOutput, .NOSPC => return error.NoSpaceLeft, .DQUOT => return error.DiskQuota, else => |err| return unexpectedErrno(err), } } /// Write all pending file contents for the specified file descriptor to the underlying filesystem, but not necessarily the metadata. pub fn fdatasync(fd: fd_t) SyncError!void { if (builtin.os.tag == .windows) { return fsync(fd) catch |err| switch (err) { SyncError.AccessDenied => return, // fdatasync doesn't promise that the access time was synced else => return err, }; } const rc = system.fdatasync(fd); switch (errno(rc)) { .SUCCESS => return, .BADF, .INVAL, .ROFS => unreachable, .IO => return error.InputOutput, .NOSPC => return error.NoSpaceLeft, .DQUOT => return error.DiskQuota, else => |err| return unexpectedErrno(err), } } pub const PrctlError = error{ /// Can only occur with PR_SET_SECCOMP/SECCOMP_MODE_FILTER or /// PR_SET_MM/PR_SET_MM_EXE_FILE AccessDenied, /// Can only occur with PR_SET_MM/PR_SET_MM_EXE_FILE InvalidFileDescriptor, InvalidAddress, /// Can only occur with PR_SET_SPECULATION_CTRL, PR_MPX_ENABLE_MANAGEMENT, /// or PR_MPX_DISABLE_MANAGEMENT UnsupportedFeature, /// Can only occur wih PR_SET_FP_MODE OperationNotSupported, PermissionDenied, } || UnexpectedError; pub fn prctl(option: PR, args: anytype) PrctlError!u31 { if (@typeInfo(@TypeOf(args)) != .Struct) @compileError("Expected tuple or struct argument, found " ++ @typeName(@TypeOf(args))); if (args.len > 4) @compileError("prctl takes a maximum of 4 optional arguments"); var buf: [4]usize = undefined; { comptime var i = 0; inline while (i < args.len) : (i += 1) buf[i] = args[i]; } const rc = system.prctl(@enumToInt(option), buf[0], buf[1], buf[2], buf[3]); switch (errno(rc)) { .SUCCESS => return @intCast(u31, rc), .ACCES => return error.AccessDenied, .BADF => return error.InvalidFileDescriptor, .FAULT => return error.InvalidAddress, .INVAL => unreachable, .NODEV, .NXIO => return error.UnsupportedFeature, .OPNOTSUPP => return error.OperationNotSupported, .PERM, .BUSY => return error.PermissionDenied, .RANGE => unreachable, else => |err| return unexpectedErrno(err), } } pub const GetrlimitError = UnexpectedError; pub fn getrlimit(resource: rlimit_resource) GetrlimitError!rlimit { const getrlimit_sym = if (builtin.os.tag == .linux and builtin.link_libc) system.getrlimit64 else system.getrlimit; var limits: rlimit = undefined; switch (errno(getrlimit_sym(resource, &limits))) { .SUCCESS => return limits, .FAULT => unreachable, // bogus pointer .INVAL => unreachable, else => |err| return unexpectedErrno(err), } } pub const SetrlimitError = error{ PermissionDenied, LimitTooBig } || UnexpectedError; pub fn setrlimit(resource: rlimit_resource, limits: rlimit) SetrlimitError!void { const setrlimit_sym = if (builtin.os.tag == .linux and builtin.link_libc) system.setrlimit64 else system.setrlimit; switch (errno(setrlimit_sym(resource, &limits))) { .SUCCESS => return, .FAULT => unreachable, // bogus pointer .INVAL => return error.LimitTooBig, // this could also mean "invalid resource", but that would be unreachable .PERM => return error.PermissionDenied, else => |err| return unexpectedErrno(err), } } pub const MadviseError = error{ /// advice is MADV.REMOVE, but the specified address range is not a shared writable mapping. AccessDenied, /// advice is MADV.HWPOISON, but the caller does not have the CAP_SYS_ADMIN capability. PermissionDenied, /// A kernel resource was temporarily unavailable. SystemResources, /// One of the following: /// * addr is not page-aligned or length is negative /// * advice is not valid /// * advice is MADV.DONTNEED or MADV.REMOVE and the specified address range /// includes locked, Huge TLB pages, or VM_PFNMAP pages. /// * advice is MADV.MERGEABLE or MADV.UNMERGEABLE, but the kernel was not /// configured with CONFIG_KSM. /// * advice is MADV.FREE or MADV.WIPEONFORK but the specified address range /// includes file, Huge TLB, MAP.SHARED, or VM_PFNMAP ranges. InvalidSyscall, /// (for MADV.WILLNEED) Paging in this area would exceed the process's /// maximum resident set size. WouldExceedMaximumResidentSetSize, /// One of the following: /// * (for MADV.WILLNEED) Not enough memory: paging in failed. /// * Addresses in the specified range are not currently mapped, or /// are outside the address space of the process. OutOfMemory, /// The madvise syscall is not available on this version and configuration /// of the Linux kernel. MadviseUnavailable, /// The operating system returned an undocumented error code. Unexpected, }; /// Give advice about use of memory. /// This syscall is optional and is sometimes configured to be disabled. pub fn madvise(ptr: [*]align(mem.page_size) u8, length: usize, advice: u32) MadviseError!void { switch (errno(system.madvise(ptr, length, advice))) { .SUCCESS => return, .ACCES => return error.AccessDenied, .AGAIN => return error.SystemResources, .BADF => unreachable, // The map exists, but the area maps something that isn't a file. .INVAL => return error.InvalidSyscall, .IO => return error.WouldExceedMaximumResidentSetSize, .NOMEM => return error.OutOfMemory, .NOSYS => return error.MadviseUnavailable, else => |err| return unexpectedErrno(err), } } pub const PerfEventOpenError = error{ /// Returned if the perf_event_attr size value is too small (smaller /// than PERF_ATTR_SIZE_VER0), too big (larger than the page size), /// or larger than the kernel supports and the extra bytes are not /// zero. When E2BIG is returned, the perf_event_attr size field is /// overwritten by the kernel to be the size of the structure it was /// expecting. TooBig, /// Returned when the requested event requires CAP_SYS_ADMIN permis‐ /// sions (or a more permissive perf_event paranoid setting). Some /// common cases where an unprivileged process may encounter this /// error: attaching to a process owned by a different user; moni‐ /// toring all processes on a given CPU (i.e., specifying the pid /// argument as -1); and not setting exclude_kernel when the para‐ /// noid setting requires it. /// Also: /// Returned on many (but not all) architectures when an unsupported /// exclude_hv, exclude_idle, exclude_user, or exclude_kernel set‐ /// ting is specified. /// It can also happen, as with EACCES, when the requested event re‐ /// quires CAP_SYS_ADMIN permissions (or a more permissive /// perf_event paranoid setting). This includes setting a break‐ /// point on a kernel address, and (since Linux 3.13) setting a ker‐ /// nel function-trace tracepoint. PermissionDenied, /// Returned if another event already has exclusive access to the /// PMU. DeviceBusy, /// Each opened event uses one file descriptor. If a large number /// of events are opened, the per-process limit on the number of /// open file descriptors will be reached, and no more events can be /// created. ProcessResources, EventRequiresUnsupportedCpuFeature, /// Returned if you try to add more breakpoint /// events than supported by the hardware. TooManyBreakpoints, /// Returned if PERF_SAMPLE_STACK_USER is set in sample_type and it /// is not supported by hardware. SampleStackNotSupported, /// Returned if an event requiring a specific hardware feature is /// requested but there is no hardware support. This includes re‐ /// questing low-skid events if not supported, branch tracing if it /// is not available, sampling if no PMU interrupt is available, and /// branch stacks for software events. EventNotSupported, /// Returned if PERF_SAMPLE_CALLCHAIN is requested and sam‐ /// ple_max_stack is larger than the maximum specified in /// /proc/sys/kernel/perf_event_max_stack. SampleMaxStackOverflow, /// Returned if attempting to attach to a process that does not exist. ProcessNotFound, } || UnexpectedError; pub fn perf_event_open( attr: *linux.perf_event_attr, pid: pid_t, cpu: i32, group_fd: fd_t, flags: usize, ) PerfEventOpenError!fd_t { const rc = system.perf_event_open(attr, pid, cpu, group_fd, flags); switch (errno(rc)) { .SUCCESS => return @intCast(fd_t, rc), .@"2BIG" => return error.TooBig, .ACCES => return error.PermissionDenied, .BADF => unreachable, // group_fd file descriptor is not valid. .BUSY => return error.DeviceBusy, .FAULT => unreachable, // Segmentation fault. .INVAL => unreachable, // Bad attr settings. .INTR => unreachable, // Mixed perf and ftrace handling for a uprobe. .MFILE => return error.ProcessResources, .NODEV => return error.EventRequiresUnsupportedCpuFeature, .NOENT => unreachable, // Invalid type setting. .NOSPC => return error.TooManyBreakpoints, .NOSYS => return error.SampleStackNotSupported, .OPNOTSUPP => return error.EventNotSupported, .OVERFLOW => return error.SampleMaxStackOverflow, .PERM => return error.PermissionDenied, .SRCH => return error.ProcessNotFound, else => |err| return unexpectedErrno(err), } } pub const TimerFdCreateError = error{ AccessDenied, ProcessFdQuotaExceeded, SystemFdQuotaExceeded, NoDevice, SystemResources, } || UnexpectedError; pub const TimerFdGetError = error{InvalidHandle} || UnexpectedError; pub const TimerFdSetError = TimerFdGetError || error{Canceled}; pub fn timerfd_create(clokid: i32, flags: u32) TimerFdCreateError!fd_t { var rc = linux.timerfd_create(clokid, flags); return switch (errno(rc)) { .SUCCESS => @intCast(fd_t, rc), .INVAL => unreachable, .MFILE => return error.ProcessFdQuotaExceeded, .NFILE => return error.SystemFdQuotaExceeded, .NODEV => return error.NoDevice, .NOMEM => return error.SystemResources, .PERM => return error.AccessDenied, else => |err| return unexpectedErrno(err), }; } pub fn timerfd_settime(fd: i32, flags: u32, new_value: *const linux.itimerspec, old_value: ?*linux.itimerspec) TimerFdSetError!void { var rc = linux.timerfd_settime(fd, flags, new_value, old_value); return switch (errno(rc)) { .SUCCESS => {}, .BADF => error.InvalidHandle, .FAULT => unreachable, .INVAL => unreachable, .CANCELED => error.Canceled, else => |err| return unexpectedErrno(err), }; } pub fn timerfd_gettime(fd: i32) TimerFdGetError!linux.itimerspec { var curr_value: linux.itimerspec = undefined; var rc = linux.timerfd_gettime(fd, &curr_value); return switch (errno(rc)) { .SUCCESS => return curr_value, .BADF => error.InvalidHandle, .FAULT => unreachable, .INVAL => unreachable, else => |err| return unexpectedErrno(err), }; }