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Neither the name of the University nor the names of its contributors .\" may be used to endorse or promote products derived from this software .\" without specific prior written permission. .\" .\" THIS SOFTWARE IS PROVIDED BY THE REGENTS 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. .\" .Dd June 28, 2023 .Dt INDENT 1 .Os .Sh NAME .Nm indent .Nd indent and format C program source .Sh SYNOPSIS .Nm .Op Ar input-file Op Ar output-file .Op Fl bacc | Fl nbacc .Op Fl bad | Fl nbad .Op Fl badp | Fl nbadp .Op Fl bap | Fl nbap .Op Fl bbb | Fl nbbb .Op Fl \&bc | Fl nbc .Op Fl \&bl | Fl \&br .Op Fl bs | Fl nbs .Op Fl c Ns Ar n .Op Fl \&cd Ns Ar n .Bk -words .Op Fl cdb | Fl ncdb .Ek .Op Fl \&ce | Fl nce .Op Fl \&ci Ns Ar n .Op Fl cli Ns Ar n .Op Fl cs | Fl ncs .Op Fl d Ns Ar n .Op Fl \&di Ns Ar n .Op Fl dj | Fl ndj .Bk -words .Op Fl ei | Fl nei .Op Fl eei | Fl neei .Ek .Bk -words .Op Fl fbs | Fl nfbs .Op Fl fc1 | Fl nfc1 .Op Fl fcb | Fl nfcb .Ek .Op Fl i Ns Ar n .Op Fl \&ip | Fl nip .Op Fl l Ns Ar n .Op Fl \&lc Ns Ar n .Op Fl \&ldi Ns Ar n .Op Fl \&lp | Fl nlp .Op Fl \&lpl | Fl nlpl .Op Fl npro .Op Fl P Ns Ar file .Op Fl pcs | Fl npcs .Op Fl ps | Fl nps .Op Fl psl | Fl npsl .Op Fl \&sc | Fl nsc .Bk -words .Op Fl sob | Fl nsob .Ek .Op Fl \&st .Op Fl \&ta .Op Fl T Ns Ar typename .Op Fl ts Ns Ar n .Op Fl U Ns Ar file .Op Fl ut | Fl nut .Op Fl v | Fl \&nv .Op Fl -version .Sh DESCRIPTION The .Nm utility is a .Em C program formatter. It reformats the .Em C program in the .Ar input-file according to the switches. The switches which can be specified are described below. They may appear before or after the file names. .Pp .Sy NOTE : If you only specify an .Ar input-file , the formatting is done `in-place', that is, the formatted file is written back into .Ar input-file and a backup copy of .Ar input-file is written in the current directory. If .Ar input-file is named .Sq Pa /blah/blah/file , the backup file is named .Sq Pa file.BAK by default. The extension used for the backup file may be overridden using the .Ev SIMPLE_BACKUP_SUFFIX environment variable. .Pp If .Ar output-file is specified, .Nm checks to make sure that it is different from .Ar input-file . .Pp The options listed below control the formatting style imposed by .Nm . .Bl -tag -width Op .It Fl bacc , nbacc If .Fl bacc is specified, a blank line is forced around every conditional compilation block. For example, in front of every #ifdef and after every #endif. Other blank lines surrounding such blocks will be swallowed. Default: .Fl nbacc . .It Fl bad , nbad If .Fl bad is specified, a blank line is forced after every block of declarations. Default: .Fl nbad . .It Fl badp , nbadp This is vaguely similar to .Fl bad except that it only applies to the first set of declarations in a procedure (just after the first `{') and it causes a blank line to be generated even if there are no declarations. The default is .Fl nbadp . .It Fl bap , nbap If .Fl bap is specified, a blank line is forced after every procedure body. Default: .Fl nbap . .It Fl bbb , nbbb If .Fl bbb is specified, a blank line is forced before every block comment. Default: .Fl nbbb . .It Fl \&bc , nbc If .Fl \&bc is specified, then a newline is forced after each comma in a declaration. .Fl nbc turns off this option. Default: .Fl \&nbc . .It Fl \&bl , \&br Specifying .Fl \&bl lines up compound statements like this: .Bd -literal -offset indent if (...) { code } .Ed .Pp Specifying .Fl \&br (the default) makes them look like this: .Bd -literal -offset indent if (...) { code } .Ed .It Fl bs , nbs Whether a blank should always be inserted after sizeof. The default is .Fl nbs . .It Fl c Ns Ar n The column in which comments on code start. The default is 33. .It Fl cd Ns Ar n The column in which comments on declarations start. The default is for these comments to start in the same column as those on code. .It Fl cdb , ncdb Enables (disables) the placement of comment delimiters on blank lines. With this option enabled, comments look like this: .Bd -literal -offset indent /* * this is a comment */ .Ed .Pp Rather than like this: .Bd -literal -offset indent /* this is a comment */ .Ed .Pp This only affects block comments, not comments to the right of code. The default is .Fl cdb . .It Fl ce , nce Enables (disables) forcing of `else's to cuddle up to the immediately preceding `}'. The default is .Fl \&ce . .It Fl \&ci Ns Ar n Sets the continuation indent to be .Ar n . Continuation lines will be indented that far from the beginning of the first line of the statement. Parenthesized expressions have extra indentation added to indicate the nesting, unless .Fl \&lp is in effect or the continuation indent is exactly half of the main indent. .Fl \&ci defaults to the same value as .Fl i . .It Fl cli Ns Ar n Causes case labels to be indented .Ar n tab stops to the right of the containing .Ic switch statement. .Fl cli0.5 causes case labels to be indented half a tab stop. The default is .Fl cli0 . .It Fl cs , ncs Control whether parenthesized type names in casts are followed by a space or not. The default is .Fl ncs . .It Fl d Ns Ar n Controls the placement of comments which are not to the right of code. For example, .Fl \&d\&1 means that such comments are placed one indentation level to the left of code. Specifying the default .Fl \&d\&0 lines up these comments with the code. See the section on comment indentation below. .It Fl \&di Ns Ar n Specifies the indentation, in character positions, of global variable names and all struct/union member names relative to the beginning of their type declaration. The default is .Fl di16 . .It Fl dj , ndj .Fl \&dj left justifies declarations. .Fl ndj indents declarations the same as code. The default is .Fl ndj . .It Fl \&ei , nei Enables (disables) special .Ic else-if processing. If it is enabled, an .Ic if following an .Ic else will have the same indentation as the preceding .Ic \&if statement. The default is .Fl ei . .It Fl eei , neei Enables (disables) extra indentation on continuation lines of the expression part of .Ic if and .Ic while statements. These continuation lines will be indented one extra level. The default is .Fl neei . .It Fl fbs , nfbs Enables (disables) splitting the function declaration and opening brace across two lines. The default is .Fl fbs . .It Fl fc1 , nfc1 Enables (disables) the formatting of comments that start in column 1. Often, comments whose leading `/' is in column 1 have been carefully hand formatted by the programmer. In such cases, .Fl nfc1 should be used. The default is .Fl fc1 . .It Fl fcb , nfcb Enables (disables) the formatting of block comments (ones that begin with `/*\\n'). Often, block comments have been not so carefully hand formatted by the programmer, but reformatting that would just change the line breaks is not wanted. In such cases, .Fl nfcb should be used. Block comments are then handled like box comments. The default is .Fl fcb . .It Fl i Ns Ar n The number of columns for one indentation level. The default is 8. .It Fl \&ip , nip Enables (disables) the indentation of parameter declarations from the left margin. The default is .Fl \&ip . .It Fl l Ns Ar n Maximum length of an output line. The default is 78. .It Fl lc Ns Ar n Maximum length of an output line in a block comment. The default is 0, which means to limit block comment lines in accordance with .Fl l . .It Fl \&ldi Ns Ar n Specifies the indentation, in character positions, of local variable names relative to the beginning of their type declaration. The default is for local variable names to be indented by the same amount as global ones. .It Fl \&lp , nlp Lines up code surrounded by parentheses in continuation lines. With .Fl \&lp , if a line has a left paren which is not closed on that line, then continuation lines will be lined up to start at the character position just after the left paren. For example, here is how a piece of continued code looks with .Fl nlp in effect: .Bd -literal -offset indent p1 = first_procedure(second_procedure(p2, p3), \ \ third_procedure(p4, p5)); .Ed .Pp With .Fl lp in effect (the default) the code looks somewhat clearer: .Bd -literal -offset indent p1\ =\ first_procedure(second_procedure(p2,\ p3), \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ third_procedure(p4,\ p5)); .Ed .Pp Inserting two more newlines we get: .Bd -literal -offset indent p1\ =\ first_procedure(second_procedure(p2, \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ p3), \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ third_procedure(p4, \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ p5)); .Ed .It Fl \&lpl , nlpl With .Fl \&lpl , code surrounded by parentheses in continuation lines is lined up even if it would extend past the right margin. With .Fl \&nlpl (the default), such a line that would extend past the right margin is moved left to keep it within the margin, if that does not require placing it to the left of the prevailing indentation level. These switches have no effect if .Fl nlp is selected. .It Fl npro Causes the profile files, .Sq Pa ./.indent.pro and .Sq Pa ~/.indent.pro , to be ignored. .It Fl P Ns Ar file Read profile from .Ar file . .It Fl pcs , npcs If true .Pq Fl pcs all procedure calls will have a space inserted between the name and the `('. The default is .Fl npcs . .It Fl ps , nps If true .Pq Fl ps the pointer dereference operator (`->') is treated like any other binary operator. The default is .Fl nps . .It Fl psl , npsl If true .Pq Fl psl the names of procedures being defined are placed in column 1 \- their types, if any, will be left on the previous lines. The default is .Fl psl . .It Fl \&sc , nsc Enables (disables) the placement of asterisks (`*'s) at the left edge of all comments. The default is .Fl sc . .It Fl sob , nsob If .Fl sob is specified, indent will swallow optional blank lines. You can use this to get rid of blank lines after declarations. Default: .Fl nsob . .It Fl \&st Causes .Nm to take its input from stdin and put its output to stdout. .It Fl ta Automatically add all identifiers ending in "_t" to the list of type keywords. .It Fl T Ns Ar typename Adds .Ar typename to the list of type keywords. Names accumulate: .Fl T can be specified more than once. You need to specify all the typenames that appear in your program that are defined by .Ic typedef \- nothing will be harmed if you miss a few, but the program will not be formatted as nicely as it should. This sounds like a painful thing to have to do, but it is really a symptom of a problem in C: .Ic typedef causes a syntactic change in the language and .Nm cannot find all instances of .Ic typedef . .It Fl ts Ns Ar n Assumed distance between tab stops. The default is 8. .It Fl U Ns Ar file Adds type names from .Ar file to the list of type keywords. .It Fl ut , nut Enables (disables) the use of tab characters in the output. The default is .Fl ut . .It Fl v , \&nv .Fl v turns on `verbose' mode; .Fl \&nv turns it off. When in verbose mode, .Nm reports when it splits one line of input into two or more lines of output, and gives some size statistics at completion. The default is .Fl \&nv . .It Fl -version Causes .Nm to print its version number and exit. .El .Pp You may set up your own `profile' of defaults to .Nm by creating a file called .Pa .indent.pro in your login directory and/or the current directory and including whatever switches you like. A `.indent.pro' in the current directory takes precedence over the one in your login directory. If .Nm is run and a profile file exists, then it is read to set up the program's defaults. Switches on the command line, though, always override profile switches. The switches should be separated by spaces, tabs or newlines. .Pp .Ss Comments .Sq Em Box .Em comments . The .Nm utility assumes that any comment with a dash or star immediately after the start of comment (that is, `/*\-' or `/**') is a comment surrounded by a box of stars. Each line of such a comment is left unchanged, except that its indentation may be adjusted to account for the change in indentation of the first line of the comment. .Pp .Em Straight text . All other comments are treated as straight text. The .Nm utility fits as many words (separated by blanks, tabs, or newlines) on a line as possible. Blank lines break paragraphs. .Ss Comment indentation If a comment is on a line with code it is started in the `comment column', which is set by the .Fl c Ns Ns Ar n command line parameter. Otherwise, the comment is started at .Ar n indentation levels less than where code is currently being placed, where .Ar n is specified by the .Fl d Ns Ns Ar n command line parameter. If the code on a line extends past the comment column, the comment starts further to the right, and the right margin may be automatically extended in extreme cases. .Ss Preprocessor lines In general, .Nm leaves preprocessor lines alone. The only reformatting that it will do is to straighten up trailing comments. It leaves embedded comments alone. Conditional compilation .Pq Ic #ifdef...#endif is recognized and .Nm attempts to correctly compensate for the syntactic peculiarities introduced. .Ss C syntax The .Nm utility understands a substantial amount about the syntax of C, but it has a `forgiving' parser. It attempts to cope with the usual sorts of incomplete and malformed syntax. In particular, the use of macros like: .Pp .Dl #define forever for(;;) .Pp is handled properly. .Sh ENVIRONMENT The .Nm utility uses the .Ev HOME environment variable. .Sh FILES .Bl -tag -width "./.indent.pro" -compact .It Pa ./.indent.pro profile file .It Pa ~/.indent.pro profile file .El .Sh HISTORY The .Nm command appeared in .Bx 4.2 . .Sh BUGS The .Nm utility has even more switches than .Xr ls 1 . .Pp A common mistake is to try to indent all the .Em C programs in a directory by typing: .Pp .Dl indent *.c .Pp This is probably a bug, not a feature.