freebsd-src/lib/libc_r/uthread/uthread_close.c
Julian Elischer 0f7d684755 Submitted by: John Birrell <cimaxp1!jb@werple.net.au>
Here are the diffs for libc_r to get it one step closer to P1003.1c
These make most of the thread/mutex/condvar structures opaque to the
user. There are three functions which have been renamed with _np
suffixes because they are extensions to P1003.1c (I did them for JAVA,
which needs to suspend/resume threads and also start threads suspended).

I've created a new header (pthread_np.h) for the non-POSIX stuff.

The egrep tags stuff in /usr/src/lib/libc_r/Makefile that I uncommented
doesn't work. I think its best to delete it. I don't think libc_r needs
tags anyway, 'cause most of the source is in libc which does have tags.

also:

Here's the first batch of man pages for the thread functions.
The diff to /usr/src/lib/libc_r/Makefile removes some stuff that was
inherited from /usr/src/lib/libc/Makefile that should only be done with
libc.

also:

I should have sent this diff with the pthread(3) man page.
It allows people to type

make -DWANT_LIBC_R world

to get libc_r built with the rest of the world. I put this in the
pthread(3) man page.  The default is still not to build libc_r.


also:
The diff attached adds a pthread(3) man page to /usr/src/share/man/man3.
The idea is that without libc_r installed, this man page will give people
enough info to know that they have to build libc_r.
1996-08-20 08:22:01 +00:00

97 lines
3.6 KiB
C

/*
* Copyright (c) 1995 John Birrell <jb@cimlogic.com.au>.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by John Birrell.
* 4. Neither the name of the author nor the names of any co-contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY JOHN BIRRELL AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
*/
#include <stdlib.h>
#include <unistd.h>
#include <fcntl.h>
#include <sys/stat.h>
#ifdef _THREAD_SAFE
#include <pthread.h>
#include "pthread_private.h"
int
close(int fd)
{
int flags;
int ret;
int status;
struct stat sb;
/* Lock the file descriptor while the file is closed: */
if ((ret = _thread_fd_lock(fd, FD_RDWR, NULL, __FILE__, __LINE__)) == 0) {
/* Block signals: */
_thread_kern_sig_block(&status);
/* Get file descriptor status. */
fstat(fd, &sb);
/*
* Check if the file should be left as blocking.
*
* This is so that the file descriptors shared with a parent
* process aren't left set to non-blocking if the child
* closes them prior to exit. An example where this causes
* problems with /bin/sh is when a child closes stdin.
*
* Setting a file as blocking causes problems if a threaded
* parent accesses the file descriptor before the child exits.
* Once the threaded parent receives a SIGCHLD then it resets
* all of its files to non-blocking, and so it is then safe
* to access them.
*
* Pipes are not set to blocking when they are closed, as
* the parent and child will normally close the file
* descriptor of the end of the pipe that they are not
* using, which would then cause any reads to block
* indefinitely.
*/
if ((S_ISREG(sb.st_mode) || S_ISCHR(sb.st_mode)) && (_thread_fd_table[fd]->flags & O_NONBLOCK) == 0) {
/* Get the current flags: */
flags = _thread_sys_fcntl(fd, F_GETFL, NULL);
/* Clear the nonblocking file descriptor flag: */
_thread_sys_fcntl(fd, F_SETFL, flags & ~O_NONBLOCK);
}
/* Close the file descriptor: */
ret = _thread_sys_close(fd);
/* Free the file descriptor table entry: */
free(_thread_fd_table[fd]);
_thread_fd_table[fd] = NULL;
/* Unblock signals again: */
_thread_kern_sig_unblock(status);
}
return (ret);
}
#endif