2005-01-05 21:27:01 +00:00
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.\"-
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.\" Copyright (c) 1995-2005 The FreeBSD Project
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1996-08-22 16:55:15 +00:00
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.\" All rights reserved.
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.\"
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.\" Redistribution and use in source and binary forms, with or without
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.\" modification, are permitted provided that the following conditions
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.\" are met:
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.\" 1. Redistributions of source code must retain the above copyright
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.\" notice, this list of conditions and the following disclaimer.
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.\" 2. Redistributions in binary form must reproduce the above copyright
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.\" notice, this list of conditions and the following disclaimer in the
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.\" documentation and/or other materials provided with the distribution.
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.\"
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.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
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.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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.\" ARE DISCLAIMED. IN NO EVENT SHALL [your name] OR CONTRIBUTORS BE LIABLE
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.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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.\" SUCH DAMAGE.
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.\"
|
2001-12-08 17:48:18 +00:00
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|
|
.Dd December 7, 2001
|
1995-12-14 10:50:27 +00:00
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|
|
.Dt STYLE 9
|
2001-07-10 15:31:11 +00:00
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|
|
.Os
|
1995-12-14 10:50:27 +00:00
|
|
|
.Sh NAME
|
1996-02-09 16:20:10 +00:00
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|
|
.Nm style
|
2001-04-18 15:54:10 +00:00
|
|
|
.Nd "kernel source file style guide"
|
1995-12-14 10:50:27 +00:00
|
|
|
.Sh DESCRIPTION
|
1997-05-27 10:00:08 +00:00
|
|
|
This file specifies the preferred style for kernel source files in the
|
2000-11-14 11:20:58 +00:00
|
|
|
.Fx
|
2001-12-08 17:48:18 +00:00
|
|
|
source tree.
|
2001-12-13 01:31:41 +00:00
|
|
|
It is also a guide for the preferred userland code style.
|
2001-12-13 01:29:34 +00:00
|
|
|
Many of the style rules are implicit in the examples.
|
|
|
|
Be careful to check the examples before assuming that
|
2001-12-14 09:22:34 +00:00
|
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|
.Nm
|
2001-12-13 01:29:34 +00:00
|
|
|
is silent on an issue.
|
2001-02-01 16:38:02 +00:00
|
|
|
.Bd -literal
|
1995-12-14 10:50:27 +00:00
|
|
|
/*
|
2001-04-22 02:32:42 +00:00
|
|
|
* Style guide for FreeBSD. Based on the CSRG's KNF (Kernel Normal Form).
|
|
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|
*
|
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|
* @(#)style 1.14 (Berkeley) 4/28/95
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* $FreeBSD$
|
1995-12-14 10:50:27 +00:00
|
|
|
*/
|
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|
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|
/*
|
|
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|
* VERY important single-line comments look like this.
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|
*/
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|
/* Most single-line comments look like this. */
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/*
|
1995-12-21 18:35:19 +00:00
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|
* Multi-line comments look like this. Make them real sentences. Fill
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|
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|
* them so they look like real paragraphs.
|
1995-12-14 10:50:27 +00:00
|
|
|
*/
|
1996-03-31 22:36:14 +00:00
|
|
|
.Ed
|
|
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|
.Pp
|
2005-01-05 19:16:01 +00:00
|
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|
The copyright header should be a muli-line comment, with the first
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|
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|
line of the comment having a dash after the star like so:
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|
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|
.Bd -literal
|
|
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|
/*-
|
2005-01-05 21:27:01 +00:00
|
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|
* Copyright (c) 1984-2025 John Q. Public. All Rights Reserved.
|
2005-01-05 19:16:01 +00:00
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*
|
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|
* Long, boring license goes here, but redacted for brevity
|
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*/
|
|
|
|
.Ed
|
2005-01-05 21:27:01 +00:00
|
|
|
An automatic script collects license information from the tree for
|
|
|
|
all comments that start in the first column with
|
|
|
|
.Dq Li "/*-" .
|
|
|
|
If you desire to flag
|
|
|
|
.Xr indent 1
|
|
|
|
to not reformat a comment that starts in the first column which is not a
|
|
|
|
license or copyright notice, change the dash to a star for those
|
|
|
|
comments.
|
|
|
|
Coments starting in columns other than the first comment are never
|
|
|
|
considered license statements.
|
2005-01-05 19:16:01 +00:00
|
|
|
.Pp
|
2001-04-22 02:32:42 +00:00
|
|
|
After any copyright header, there is a blank line, and the
|
|
|
|
.Va rcsid
|
|
|
|
for source files.
|
|
|
|
Version control system ID tags should only exist once in a file
|
2002-01-31 13:26:29 +00:00
|
|
|
(unlike in this one).
|
2001-09-05 00:46:51 +00:00
|
|
|
Non-C/C++ source files follow the example above, while C/C++ source files
|
|
|
|
follow the one below.
|
2002-01-31 13:26:29 +00:00
|
|
|
All VCS (version control system) revision identification in files obtained
|
2001-09-05 00:46:51 +00:00
|
|
|
from elsewhere should be maintained, including, where applicable, multiple IDs
|
2001-05-17 02:05:36 +00:00
|
|
|
showing a file's history.
|
2002-02-01 01:17:22 +00:00
|
|
|
In general, do not edit foreign IDs or their infrastructure.
|
2002-03-18 11:03:57 +00:00
|
|
|
Unless otherwise wrapped (such as
|
|
|
|
.Dq Li "#if defined(LIBC_SCCS)" ) ,
|
2002-01-31 13:26:29 +00:00
|
|
|
enclose both in
|
|
|
|
.Dq Li "#if 0 ... #endif"
|
|
|
|
to hide any uncompilable bits
|
|
|
|
and to keep the IDs out of object files.
|
|
|
|
Only add
|
|
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|
.Dq Li "From: "
|
|
|
|
in front of foreign VCS IDs if the file is renamed.
|
2001-04-22 02:32:42 +00:00
|
|
|
.Bd -literal
|
2002-01-31 13:26:29 +00:00
|
|
|
#if 0
|
|
|
|
#ifndef lint
|
|
|
|
static char sccsid[] = "@(#)style 1.14 (Berkeley) 4/28/95";
|
2003-03-25 19:46:55 +00:00
|
|
|
#endif /* not lint */
|
2002-01-31 13:26:29 +00:00
|
|
|
#endif
|
2004-06-26 09:02:44 +00:00
|
|
|
|
2001-09-15 16:47:24 +00:00
|
|
|
#include <sys/cdefs.h>
|
2001-10-01 16:13:59 +00:00
|
|
|
__FBSDID("$FreeBSD$");
|
2001-04-22 02:32:42 +00:00
|
|
|
.Ed
|
|
|
|
.Pp
|
2001-09-05 00:46:51 +00:00
|
|
|
Leave another blank line before the header files.
|
2001-04-22 02:32:42 +00:00
|
|
|
.Pp
|
2001-12-08 17:48:18 +00:00
|
|
|
Kernel include files (i.e.\&
|
|
|
|
.Pa sys/*.h )
|
|
|
|
come first; normally, include
|
2003-09-08 19:57:22 +00:00
|
|
|
.In sys/types.h
|
2001-12-08 17:48:18 +00:00
|
|
|
OR
|
2003-09-08 19:57:22 +00:00
|
|
|
.In sys/param.h ,
|
2001-12-08 17:48:18 +00:00
|
|
|
but not both.
|
2003-09-08 19:57:22 +00:00
|
|
|
.In sys/types.h
|
2001-12-08 17:48:18 +00:00
|
|
|
includes
|
2003-09-08 19:57:22 +00:00
|
|
|
.In sys/cdefs.h ,
|
2001-12-08 17:48:18 +00:00
|
|
|
and it is okay to depend on that.
|
2001-02-01 16:38:02 +00:00
|
|
|
.Bd -literal
|
2000-07-17 19:05:57 +00:00
|
|
|
#include <sys/types.h> /* Non-local includes in angle brackets. */
|
1996-03-31 22:36:14 +00:00
|
|
|
.Ed
|
|
|
|
.Pp
|
2001-09-05 00:46:51 +00:00
|
|
|
For a network program, put the network include files next.
|
2001-02-01 16:38:02 +00:00
|
|
|
.Bd -literal
|
1995-12-14 10:50:27 +00:00
|
|
|
#include <net/if.h>
|
|
|
|
#include <net/if_dl.h>
|
|
|
|
#include <net/route.h>
|
|
|
|
#include <netinet/in.h>
|
|
|
|
#include <protocols/rwhod.h>
|
1996-03-31 22:36:14 +00:00
|
|
|
.Ed
|
|
|
|
.Pp
|
2001-12-13 01:29:34 +00:00
|
|
|
Do not use files in
|
|
|
|
.Pa /usr/include
|
|
|
|
for files in the kernel.
|
|
|
|
.Pp
|
2001-12-08 17:48:18 +00:00
|
|
|
Leave a blank line before the next group, the
|
2004-06-16 08:33:57 +00:00
|
|
|
.Pa /usr/include
|
2003-09-27 22:17:37 +00:00
|
|
|
files,
|
2001-09-05 00:46:51 +00:00
|
|
|
which should be sorted alphabetically by name.
|
2001-02-01 16:38:02 +00:00
|
|
|
.Bd -literal
|
1995-12-14 10:50:27 +00:00
|
|
|
#include <stdio.h>
|
1996-03-31 22:36:14 +00:00
|
|
|
.Ed
|
|
|
|
.Pp
|
2001-12-08 17:48:18 +00:00
|
|
|
Global pathnames are defined in
|
2003-09-08 19:57:22 +00:00
|
|
|
.In paths.h .
|
2001-12-08 17:48:18 +00:00
|
|
|
Pathnames local
|
|
|
|
to the program go in
|
|
|
|
.Qq Pa pathnames.h
|
|
|
|
in the local directory.
|
2001-02-01 16:38:02 +00:00
|
|
|
.Bd -literal
|
1995-12-14 10:50:27 +00:00
|
|
|
#include <paths.h>
|
1996-03-31 22:36:14 +00:00
|
|
|
.Ed
|
|
|
|
.Pp
|
2001-09-05 00:46:51 +00:00
|
|
|
Leave another blank line before the user include files.
|
2001-02-01 16:38:02 +00:00
|
|
|
.Bd -literal
|
1995-12-21 18:35:19 +00:00
|
|
|
#include "pathnames.h" /* Local includes in double quotes. */
|
1996-03-31 22:36:14 +00:00
|
|
|
.Ed
|
|
|
|
.Pp
|
2001-12-08 17:48:18 +00:00
|
|
|
Do not
|
|
|
|
.Ic #define
|
|
|
|
or declare names in the implementation namespace except
|
2000-08-08 09:54:57 +00:00
|
|
|
for implementing application interfaces.
|
|
|
|
.Pp
|
|
|
|
The names of
|
2001-11-21 12:07:24 +00:00
|
|
|
.Dq unsafe
|
2000-08-08 09:54:57 +00:00
|
|
|
macros (ones that have side effects), and the names of macros for
|
|
|
|
manifest constants, are all in uppercase.
|
|
|
|
The expansions of expression-like macros are either a single token
|
|
|
|
or have outer parentheses.
|
2001-07-14 19:41:16 +00:00
|
|
|
Put a single tab character between the
|
2001-12-08 17:48:18 +00:00
|
|
|
.Ic #define
|
2001-07-14 19:41:16 +00:00
|
|
|
and the macro name.
|
2000-08-08 09:54:57 +00:00
|
|
|
If a macro is an inline expansion of a function, the function name is
|
|
|
|
all in lowercase and the macro has the same name all in uppercase.
|
|
|
|
.\" XXX the above conflicts with ANSI style where the names are the
|
|
|
|
.\" same and you #undef the macro (if any) to get the function.
|
|
|
|
.\" It is not followed for MALLOC(), and not very common if inline
|
|
|
|
.\" functions are used.
|
2000-07-18 14:41:01 +00:00
|
|
|
Right-justify the
|
1999-08-02 04:00:33 +00:00
|
|
|
backslashes; it makes it easier to read.
|
1997-12-07 20:19:20 +00:00
|
|
|
If the macro encapsulates a compound statement, enclose it in a
|
2001-12-08 17:48:18 +00:00
|
|
|
.Ic do
|
1997-12-07 20:19:20 +00:00
|
|
|
loop,
|
2001-07-14 19:41:16 +00:00
|
|
|
so that it can safely be used in
|
2001-12-08 17:48:18 +00:00
|
|
|
.Ic if
|
1997-12-07 20:19:20 +00:00
|
|
|
statements.
|
1997-12-07 20:25:45 +00:00
|
|
|
Any final statement-terminating semicolon should be
|
1997-12-07 20:19:20 +00:00
|
|
|
supplied by the macro invocation rather than the macro, to make parsing easier
|
|
|
|
for pretty-printers and editors.
|
2001-02-01 16:38:02 +00:00
|
|
|
.Bd -literal
|
1997-12-07 20:19:20 +00:00
|
|
|
#define MACRO(x, y) do { \e
|
1995-12-21 18:35:19 +00:00
|
|
|
variable = (x) + (y); \e
|
|
|
|
(y) += 2; \e
|
2002-02-27 23:16:34 +00:00
|
|
|
} while (0)
|
1996-03-31 22:36:14 +00:00
|
|
|
.Ed
|
|
|
|
.Pp
|
2002-11-01 16:20:31 +00:00
|
|
|
When code is conditionally compiled using
|
2002-10-28 19:33:22 +00:00
|
|
|
.Ic #ifdef
|
|
|
|
or
|
|
|
|
.Ic #if ,
|
|
|
|
a comment may be added following the matching
|
|
|
|
.Ic #endif
|
|
|
|
or
|
|
|
|
.Ic #else
|
2002-11-01 16:20:31 +00:00
|
|
|
to permit the reader to easily discern where conditionally compiled code
|
2002-10-28 19:33:22 +00:00
|
|
|
regions end.
|
|
|
|
This comment should be used only for (subjectively) long regions, regions
|
|
|
|
greater than 20 lines, or where a series of nested
|
|
|
|
.Ic #ifdef 's
|
|
|
|
may be confusing to the reader.
|
2002-11-01 16:20:31 +00:00
|
|
|
Exceptions may be made for cases where code is conditionally not compiled for
|
2002-11-29 11:39:20 +00:00
|
|
|
the purposes of
|
|
|
|
.Xr lint 1 ,
|
|
|
|
even though the uncompiled region may be small.
|
2002-11-01 16:20:31 +00:00
|
|
|
The comment should be separated from the
|
2002-10-28 19:33:22 +00:00
|
|
|
.Ic #endif
|
|
|
|
or
|
|
|
|
.Ic #else
|
|
|
|
by a single space.
|
2002-11-01 16:20:31 +00:00
|
|
|
For short conditionally compiled regions, a closing comment should not be
|
2002-10-28 19:33:22 +00:00
|
|
|
used.
|
|
|
|
.Pp
|
|
|
|
The comment for
|
|
|
|
.Ic #endif
|
2002-11-01 16:20:31 +00:00
|
|
|
should match the expression used in the corresponding
|
2002-10-28 19:33:22 +00:00
|
|
|
.Ic #if
|
|
|
|
or
|
|
|
|
.Ic #ifdef .
|
|
|
|
The comment for
|
|
|
|
.Ic #else
|
2002-11-01 16:20:31 +00:00
|
|
|
and
|
|
|
|
.Ic #elif
|
|
|
|
should match the inverse of the expression(s) used in the preceding
|
2002-10-28 19:33:22 +00:00
|
|
|
.Ic #if
|
2002-11-01 16:20:31 +00:00
|
|
|
and/or
|
|
|
|
.Ic #elif
|
|
|
|
statements.
|
2002-10-28 19:33:22 +00:00
|
|
|
In the comments, the subexpression
|
|
|
|
.Dq Li defined(FOO)
|
|
|
|
is abbreviated as
|
|
|
|
.Dq Li FOO .
|
|
|
|
For the purposes of comments,
|
|
|
|
.Dq Ic #ifndef Li FOO
|
|
|
|
is treated as
|
|
|
|
.Dq Ic #if Li !defined(FOO) .
|
|
|
|
.Bd -literal
|
|
|
|
#ifdef KTRACE
|
|
|
|
#include <sys/ktrace.h>
|
|
|
|
#endif
|
|
|
|
|
|
|
|
#ifdef COMPAT_43
|
2002-11-01 16:20:31 +00:00
|
|
|
/* A large region here, or other conditional code. */
|
2002-10-28 19:33:22 +00:00
|
|
|
#else /* !COMPAT_43 */
|
|
|
|
/* Or here. */
|
|
|
|
#endif /* COMPAT_43 */
|
|
|
|
|
|
|
|
#ifndef COMPAT_43
|
2002-11-01 16:20:31 +00:00
|
|
|
/* Yet another large region here, or other conditional code. */
|
2002-10-28 19:33:22 +00:00
|
|
|
#else /* COMPAT_43 */
|
|
|
|
/* Or here. */
|
2004-06-13 21:24:56 +00:00
|
|
|
#endif /* !COMPAT_43 */
|
2002-10-28 19:33:22 +00:00
|
|
|
.Ed
|
|
|
|
.Pp
|
2004-06-16 08:33:57 +00:00
|
|
|
The project is slowly moving to use the
|
|
|
|
.St -isoC-99
|
2003-09-27 22:17:37 +00:00
|
|
|
unsigned integer identifiers of the form
|
2004-06-16 08:33:57 +00:00
|
|
|
.Vt uintXX_t
|
|
|
|
in preference to the older
|
|
|
|
.Bx Ns -style
|
|
|
|
integer identifiers of the form
|
|
|
|
.Vt u_intXX_t .
|
2003-09-27 22:17:37 +00:00
|
|
|
New code should use the former, and old code should be converted to
|
|
|
|
the new form if other major work is being done in that area and
|
2004-06-16 08:33:57 +00:00
|
|
|
there is no overriding reason to prefer the older
|
|
|
|
.Bx Ns -style .
|
2003-09-27 22:17:37 +00:00
|
|
|
Like white-space commits, care should be taken in making
|
2004-06-16 08:33:57 +00:00
|
|
|
.Vt uintXX_t
|
2003-09-27 22:17:37 +00:00
|
|
|
only commits.
|
|
|
|
.Pp
|
1997-12-07 20:19:20 +00:00
|
|
|
Enumeration values are all uppercase.
|
2001-02-01 16:38:02 +00:00
|
|
|
.Bd -literal
|
1995-12-14 10:50:27 +00:00
|
|
|
enum enumtype { ONE, TWO } et;
|
1996-03-31 22:36:14 +00:00
|
|
|
.Ed
|
|
|
|
.Pp
|
2002-09-10 14:48:38 +00:00
|
|
|
In declarations, do not put any whitespace between asterisks and
|
|
|
|
adjacent tokens, except for tokens that are identifiers related to
|
2002-11-29 11:39:20 +00:00
|
|
|
types.
|
|
|
|
(These identifiers are the names of basic types, type
|
|
|
|
qualifiers, and
|
|
|
|
.Ic typedef Ns -names
|
|
|
|
other than the one being declared.)
|
2002-12-27 12:15:40 +00:00
|
|
|
Separate these identifiers from asterisks using a single space.
|
2002-09-10 14:48:38 +00:00
|
|
|
.Pp
|
1996-03-31 22:36:14 +00:00
|
|
|
When declaring variables in structures, declare them sorted by use, then
|
2004-12-02 23:20:17 +00:00
|
|
|
by size (largest to smallest), and then in alphabetical order.
|
2001-12-08 17:48:18 +00:00
|
|
|
The first category normally does not apply, but there are exceptions.
|
|
|
|
Each one gets its own line.
|
2001-10-23 17:40:37 +00:00
|
|
|
Try to make the structure
|
2001-10-24 22:57:39 +00:00
|
|
|
readable by aligning the member names using either one or two tabs
|
2001-10-25 11:20:15 +00:00
|
|
|
depending upon your judgment.
|
2002-07-02 01:39:35 +00:00
|
|
|
You should use one tab only if it suffices to align at least 90% of
|
|
|
|
the member names.
|
2001-10-24 22:57:39 +00:00
|
|
|
Names following extremely long types
|
2001-10-25 11:20:15 +00:00
|
|
|
should be separated by a single space.
|
1996-03-31 22:36:14 +00:00
|
|
|
.Pp
|
|
|
|
Major structures should be declared at the top of the file in which they
|
1999-08-02 04:00:33 +00:00
|
|
|
are used, or in separate header files if they are used in multiple
|
2001-12-08 17:48:18 +00:00
|
|
|
source files.
|
|
|
|
Use of the structures should be by separate declarations
|
|
|
|
and should be
|
|
|
|
.Ic extern
|
|
|
|
if they are declared in a header file.
|
2001-02-01 16:38:02 +00:00
|
|
|
.Bd -literal
|
1995-12-14 10:50:27 +00:00
|
|
|
struct foo {
|
2001-10-24 22:57:39 +00:00
|
|
|
struct foo *next; /* List of active foo. */
|
|
|
|
struct mumble amumble; /* Comment for mumble. */
|
|
|
|
int bar; /* Try to align the comments. */
|
|
|
|
struct verylongtypename *baz; /* Won't fit in 2 tabs. */
|
1995-12-14 10:50:27 +00:00
|
|
|
};
|
2001-10-24 22:57:39 +00:00
|
|
|
struct foo *foohead; /* Head of global foo list. */
|
1997-12-07 19:53:44 +00:00
|
|
|
.Ed
|
1997-12-07 20:19:20 +00:00
|
|
|
.Pp
|
1997-12-07 19:53:44 +00:00
|
|
|
Use
|
|
|
|
.Xr queue 3
|
2001-12-08 17:48:18 +00:00
|
|
|
macros rather than rolling your own lists, whenever possible.
|
|
|
|
Thus,
|
1997-12-07 19:53:44 +00:00
|
|
|
the previous example would be better written:
|
2001-02-01 16:38:02 +00:00
|
|
|
.Bd -literal
|
1997-12-07 19:53:44 +00:00
|
|
|
#include <sys/queue.h>
|
2001-12-08 17:48:18 +00:00
|
|
|
|
2001-09-04 10:00:20 +00:00
|
|
|
struct foo {
|
2001-10-25 11:20:15 +00:00
|
|
|
LIST_ENTRY(foo) link; /* Use queue macros for foo lists. */
|
2001-10-24 22:57:39 +00:00
|
|
|
struct mumble amumble; /* Comment for mumble. */
|
|
|
|
int bar; /* Try to align the comments. */
|
|
|
|
struct verylongtypename *baz; /* Won't fit in 2 tabs. */
|
1997-12-07 19:53:44 +00:00
|
|
|
};
|
2001-10-24 22:57:39 +00:00
|
|
|
LIST_HEAD(, foo) foohead; /* Head of global foo list. */
|
1997-12-07 19:53:44 +00:00
|
|
|
.Ed
|
|
|
|
.Pp
|
2001-12-08 17:48:18 +00:00
|
|
|
Avoid using typedefs for structure types.
|
2003-11-10 14:32:13 +00:00
|
|
|
Typedefs are problematic because they do not properly hide their
|
|
|
|
underlying type; for example you need to know if the typedef is
|
|
|
|
the structure itself or a pointer to the structure.
|
|
|
|
In addition they must be declared exactly once, whereas an
|
|
|
|
incomplete structure type can be mentioned as many times as
|
|
|
|
necessary.
|
|
|
|
Typedefs are difficult to use in stand-alone header files:
|
2003-11-12 10:53:52 +00:00
|
|
|
the header that defines the typedef must be included
|
2003-11-10 14:32:13 +00:00
|
|
|
before the header that uses it, or by the header that uses
|
|
|
|
it (which causes namespace pollution), or there must be a
|
|
|
|
back-door mechanism for obtaining the typedef.
|
|
|
|
.Pp
|
2001-12-08 17:48:18 +00:00
|
|
|
When convention requires a
|
|
|
|
.Ic typedef ,
|
|
|
|
make its name match the struct tag.
|
|
|
|
Avoid typedefs ending in
|
|
|
|
.Dq Li _t ,
|
2002-11-26 17:55:41 +00:00
|
|
|
except as specified in Standard C or by
|
|
|
|
.Tn POSIX .
|
2001-02-01 16:38:02 +00:00
|
|
|
.Bd -literal
|
1995-12-14 10:50:27 +00:00
|
|
|
/* Make the structure name match the typedef. */
|
2001-12-09 18:59:08 +00:00
|
|
|
typedef struct bar {
|
1995-12-21 18:35:19 +00:00
|
|
|
int level;
|
1995-12-14 10:50:27 +00:00
|
|
|
} BAR;
|
2001-12-09 18:59:08 +00:00
|
|
|
typedef int foo; /* This is foo. */
|
|
|
|
typedef const long baz; /* This is baz. */
|
1996-03-31 22:36:14 +00:00
|
|
|
.Ed
|
|
|
|
.Pp
|
|
|
|
All functions are prototyped somewhere.
|
|
|
|
.Pp
|
2004-07-03 18:29:24 +00:00
|
|
|
Function prototypes for private functions (i.e., functions not used
|
2001-12-08 17:48:18 +00:00
|
|
|
elsewhere) go at the top of the first source module.
|
|
|
|
Functions
|
1996-03-31 22:36:14 +00:00
|
|
|
local to one source module should be declared
|
2001-12-08 17:48:18 +00:00
|
|
|
.Ic static .
|
1996-03-31 22:36:14 +00:00
|
|
|
.Pp
|
|
|
|
Functions used from other parts of the kernel are prototyped in the
|
|
|
|
relevant include file.
|
2002-08-21 06:58:21 +00:00
|
|
|
Function prototypes should be listed in a logical order, preferably
|
2002-09-06 10:53:57 +00:00
|
|
|
alphabetical unless there is a compelling reason to use a different
|
2002-08-21 06:58:21 +00:00
|
|
|
ordering.
|
1996-03-31 22:36:14 +00:00
|
|
|
.Pp
|
|
|
|
Functions that are used locally in more than one module go into a
|
2001-08-10 13:45:36 +00:00
|
|
|
separate header file, e.g.\&
|
2001-12-08 17:48:18 +00:00
|
|
|
.Qq Pa extern.h .
|
1996-03-31 22:36:14 +00:00
|
|
|
.Pp
|
2002-02-01 01:26:24 +00:00
|
|
|
Do not use the
|
2001-12-08 17:48:18 +00:00
|
|
|
.Dv __P
|
2002-02-01 01:26:24 +00:00
|
|
|
macro.
|
1996-03-31 22:36:14 +00:00
|
|
|
.Pp
|
1997-05-27 10:00:08 +00:00
|
|
|
In general code can be considered
|
2001-12-08 17:48:18 +00:00
|
|
|
.Dq "new code"
|
|
|
|
when it makes up about 50% or more of the file(s) involved.
|
|
|
|
This is enough
|
|
|
|
to break precedents in the existing code and use the current
|
|
|
|
.Nm
|
|
|
|
guidelines.
|
1997-05-27 10:00:08 +00:00
|
|
|
.Pp
|
|
|
|
The kernel has a name associated with parameter types, e.g., in the kernel
|
1996-03-31 22:36:14 +00:00
|
|
|
use:
|
2001-02-01 16:38:02 +00:00
|
|
|
.Bd -literal
|
1997-05-27 10:00:08 +00:00
|
|
|
void function(int fd);
|
1996-03-31 22:36:14 +00:00
|
|
|
.Ed
|
|
|
|
.Pp
|
1999-08-02 04:00:33 +00:00
|
|
|
In header files visible to userland applications, prototypes that are
|
2001-10-03 07:33:59 +00:00
|
|
|
visible must use either
|
2001-11-21 12:07:24 +00:00
|
|
|
.Dq protected
|
2001-12-08 17:48:18 +00:00
|
|
|
names (ones beginning with an underscore)
|
|
|
|
or no names with the types.
|
2001-10-03 07:33:59 +00:00
|
|
|
It is preferable to use protected names.
|
2001-08-10 13:45:36 +00:00
|
|
|
E.g., use:
|
2001-02-01 16:38:02 +00:00
|
|
|
.Bd -literal
|
1997-05-27 10:00:08 +00:00
|
|
|
void function(int);
|
|
|
|
.Ed
|
|
|
|
.Pp
|
|
|
|
or:
|
2001-02-01 16:38:02 +00:00
|
|
|
.Bd -literal
|
1997-05-27 10:00:08 +00:00
|
|
|
void function(int _fd);
|
|
|
|
.Ed
|
|
|
|
.Pp
|
|
|
|
Prototypes may have an extra space after a tab to enable function names
|
|
|
|
to line up:
|
2001-02-01 16:38:02 +00:00
|
|
|
.Bd -literal
|
1997-05-27 10:00:08 +00:00
|
|
|
static char *function(int _arg, const char *_arg2, struct foo *_arg3,
|
2001-04-22 02:00:39 +00:00
|
|
|
struct bar *_arg4);
|
1997-05-27 10:00:08 +00:00
|
|
|
static void usage(void);
|
1995-12-14 10:50:27 +00:00
|
|
|
|
|
|
|
/*
|
|
|
|
* All major routines should have a comment briefly describing what
|
|
|
|
* they do. The comment before the "main" routine should describe
|
|
|
|
* what the program does.
|
|
|
|
*/
|
|
|
|
int
|
1997-05-27 10:00:08 +00:00
|
|
|
main(int argc, char *argv[])
|
1995-12-14 10:50:27 +00:00
|
|
|
{
|
2002-03-24 17:02:16 +00:00
|
|
|
char *ep;
|
1995-12-21 18:35:19 +00:00
|
|
|
long num;
|
|
|
|
int ch;
|
1996-03-31 22:36:14 +00:00
|
|
|
.Ed
|
|
|
|
.Pp
|
2001-12-08 17:48:18 +00:00
|
|
|
For consistency,
|
|
|
|
.Xr getopt 3
|
|
|
|
should be used to parse options.
|
|
|
|
Options
|
|
|
|
should be sorted in the
|
|
|
|
.Xr getopt 3
|
|
|
|
call and the
|
|
|
|
.Ic switch
|
|
|
|
statement, unless
|
|
|
|
parts of the
|
|
|
|
.Ic switch
|
|
|
|
cascade.
|
|
|
|
Elements in a
|
|
|
|
.Ic switch
|
|
|
|
statement that cascade should have a
|
|
|
|
.Li FALLTHROUGH
|
|
|
|
comment.
|
|
|
|
Numerical arguments should be checked for accuracy.
|
|
|
|
Code that cannot be reached should have a
|
|
|
|
.Li NOTREACHED
|
|
|
|
comment.
|
2001-02-01 16:38:02 +00:00
|
|
|
.Bd -literal
|
2004-06-26 05:15:00 +00:00
|
|
|
while ((ch = getopt(argc, argv, "abNn:")) != -1)
|
1995-12-21 18:35:19 +00:00
|
|
|
switch (ch) { /* Indent the switch. */
|
|
|
|
case 'a': /* Don't indent the case. */
|
|
|
|
aflag = 1;
|
|
|
|
/* FALLTHROUGH */
|
|
|
|
case 'b':
|
|
|
|
bflag = 1;
|
|
|
|
break;
|
2004-06-26 05:15:00 +00:00
|
|
|
case 'N':
|
|
|
|
Nflag = 1;
|
|
|
|
break;
|
1995-12-21 18:35:19 +00:00
|
|
|
case 'n':
|
|
|
|
num = strtol(optarg, &ep, 10);
|
1999-08-02 03:18:17 +00:00
|
|
|
if (num <= 0 || *ep != '\e0') {
|
|
|
|
warnx("illegal number, -n argument -- %s",
|
|
|
|
optarg);
|
|
|
|
usage();
|
|
|
|
}
|
1995-12-21 18:35:19 +00:00
|
|
|
break;
|
1996-08-24 10:49:09 +00:00
|
|
|
case '?':
|
1995-12-21 18:35:19 +00:00
|
|
|
default:
|
|
|
|
usage();
|
|
|
|
/* NOTREACHED */
|
|
|
|
}
|
|
|
|
argc -= optind;
|
|
|
|
argv += optind;
|
1996-03-31 22:36:14 +00:00
|
|
|
.Ed
|
|
|
|
.Pp
|
2001-12-08 17:48:18 +00:00
|
|
|
Space after keywords
|
|
|
|
.Pq Ic if , while , for , return , switch .
|
2002-09-10 10:54:39 +00:00
|
|
|
No braces
|
|
|
|
.Ql ( \&{
|
|
|
|
and
|
|
|
|
.Ql \&} )
|
|
|
|
are
|
1999-01-30 04:17:14 +00:00
|
|
|
used for control statements with zero or only a single statement unless that
|
|
|
|
statement is more than a single line in which case they are permitted.
|
2001-12-08 17:48:18 +00:00
|
|
|
Forever loops are done with
|
|
|
|
.Ic for Ns 's ,
|
|
|
|
not
|
|
|
|
.Ic while Ns 's .
|
2001-02-01 16:38:02 +00:00
|
|
|
.Bd -literal
|
1997-05-27 10:00:08 +00:00
|
|
|
for (p = buf; *p != '\e0'; ++p)
|
|
|
|
; /* nothing */
|
1995-12-21 18:35:19 +00:00
|
|
|
for (;;)
|
|
|
|
stmt;
|
1999-01-30 04:17:14 +00:00
|
|
|
for (;;) {
|
|
|
|
z = a + really + long + statement + that + needs +
|
2002-04-14 19:52:42 +00:00
|
|
|
two + lines + gets + indented + four + spaces +
|
1999-01-30 04:17:14 +00:00
|
|
|
on + the + second + and + subsequent + lines;
|
|
|
|
}
|
|
|
|
for (;;) {
|
|
|
|
if (cond)
|
|
|
|
stmt;
|
|
|
|
}
|
1997-05-27 10:00:08 +00:00
|
|
|
if (val != NULL)
|
|
|
|
val = realloc(val, newsize);
|
1996-03-31 22:36:14 +00:00
|
|
|
.Ed
|
|
|
|
.Pp
|
2001-12-08 17:48:18 +00:00
|
|
|
Parts of a
|
|
|
|
.Ic for
|
|
|
|
loop may be left empty.
|
|
|
|
Do not put declarations
|
1996-03-31 22:36:14 +00:00
|
|
|
inside blocks unless the routine is unusually complicated.
|
2001-02-01 16:38:02 +00:00
|
|
|
.Bd -literal
|
1995-12-21 18:35:19 +00:00
|
|
|
for (; cnt < 15; cnt++) {
|
|
|
|
stmt1;
|
|
|
|
stmt2;
|
|
|
|
}
|
1996-03-31 22:36:14 +00:00
|
|
|
.Ed
|
|
|
|
.Pp
|
1997-05-27 10:00:08 +00:00
|
|
|
Indentation is an 8 character tab.
|
1996-03-31 22:36:14 +00:00
|
|
|
Second level indents are four spaces.
|
2001-07-22 10:35:02 +00:00
|
|
|
If you have to wrap a long statement, put the operator at the end of the
|
|
|
|
line.
|
2001-02-01 16:38:02 +00:00
|
|
|
.Bd -literal
|
2002-04-14 19:52:42 +00:00
|
|
|
while (cnt < 20 && this_variable_name_is_too_long &&
|
2001-07-22 10:35:02 +00:00
|
|
|
ep != NULL)
|
1996-04-07 08:37:54 +00:00
|
|
|
z = a + really + long + statement + that + needs +
|
2002-04-14 19:52:42 +00:00
|
|
|
two + lines + gets + indented + four + spaces +
|
2001-06-18 20:36:06 +00:00
|
|
|
on + the + second + and + subsequent + lines;
|
1996-03-31 22:36:14 +00:00
|
|
|
.Ed
|
|
|
|
.Pp
|
1999-08-02 04:00:33 +00:00
|
|
|
Do not add whitespace at the end of a line, and only use tabs
|
|
|
|
followed by spaces
|
2001-12-08 17:48:18 +00:00
|
|
|
to form the indentation.
|
|
|
|
Do not use more spaces than a tab will produce
|
1997-05-27 10:00:08 +00:00
|
|
|
and do not use spaces in front of tabs.
|
|
|
|
.Pp
|
2001-12-08 17:48:18 +00:00
|
|
|
Closing and opening braces go on the same line as the
|
|
|
|
.Ic else .
|
|
|
|
Braces that are not necessary may be left out.
|
2001-02-01 16:38:02 +00:00
|
|
|
.Bd -literal
|
1995-12-21 18:35:19 +00:00
|
|
|
if (test)
|
|
|
|
stmt;
|
|
|
|
else if (bar) {
|
|
|
|
stmt;
|
|
|
|
stmt;
|
|
|
|
} else
|
|
|
|
stmt;
|
1996-03-31 22:36:14 +00:00
|
|
|
.Ed
|
|
|
|
.Pp
|
2001-12-08 17:48:18 +00:00
|
|
|
No spaces after function names.
|
|
|
|
Commas have a space after them.
|
|
|
|
No spaces
|
1997-05-27 10:00:08 +00:00
|
|
|
after
|
2001-12-08 17:48:18 +00:00
|
|
|
.Ql \&(
|
1997-05-27 10:00:08 +00:00
|
|
|
or
|
2001-12-08 17:48:18 +00:00
|
|
|
.Ql \&[
|
1997-05-27 10:00:08 +00:00
|
|
|
or preceding
|
2001-12-08 17:48:18 +00:00
|
|
|
.Ql \&]
|
1997-05-27 10:00:08 +00:00
|
|
|
or
|
2001-12-08 17:48:18 +00:00
|
|
|
.Ql \&)
|
1997-05-27 10:00:08 +00:00
|
|
|
characters.
|
2001-02-01 16:38:02 +00:00
|
|
|
.Bd -literal
|
2001-02-21 20:43:55 +00:00
|
|
|
error = function(a1, a2);
|
|
|
|
if (error != 0)
|
1995-12-21 18:35:19 +00:00
|
|
|
exit(error);
|
1996-03-31 22:36:14 +00:00
|
|
|
.Ed
|
|
|
|
.Pp
|
2001-12-08 17:48:18 +00:00
|
|
|
Unary operators do not require spaces, binary operators do.
|
|
|
|
Do not use parentheses unless they are required for precedence or unless the
|
|
|
|
statement is confusing without them.
|
|
|
|
Remember that other people may
|
|
|
|
confuse easier than you.
|
|
|
|
Do YOU understand the following?
|
2001-02-01 16:38:02 +00:00
|
|
|
.Bd -literal
|
1995-12-21 18:35:19 +00:00
|
|
|
a = b->c[0] + ~d == (e || f) || g && h ? i : j >> 1;
|
|
|
|
k = !(l & FLAGS);
|
1996-03-31 22:36:14 +00:00
|
|
|
.Ed
|
|
|
|
.Pp
|
|
|
|
Exits should be 0 on success, or according to the predefined
|
|
|
|
values in
|
|
|
|
.Xr sysexits 3 .
|
2001-02-01 16:38:02 +00:00
|
|
|
.Bd -literal
|
1996-03-31 22:36:14 +00:00
|
|
|
exit(EX_OK); /*
|
|
|
|
* Avoid obvious comments such as
|
|
|
|
* "Exit 0 on success."
|
|
|
|
*/
|
1995-12-14 10:50:27 +00:00
|
|
|
}
|
1996-03-31 22:36:14 +00:00
|
|
|
.Ed
|
|
|
|
.Pp
|
|
|
|
The function type should be on a line by itself
|
1996-04-07 08:37:54 +00:00
|
|
|
preceding the function.
|
2001-12-27 20:05:47 +00:00
|
|
|
The opening brace of the function body should be
|
|
|
|
on a line by itself.
|
2001-02-01 16:38:02 +00:00
|
|
|
.Bd -literal
|
1995-12-14 10:50:27 +00:00
|
|
|
static char *
|
1997-05-27 10:00:08 +00:00
|
|
|
function(int a1, int a2, float fl, int a4)
|
1995-12-14 10:50:27 +00:00
|
|
|
{
|
1996-03-31 22:36:14 +00:00
|
|
|
.Ed
|
|
|
|
.Pp
|
|
|
|
When declaring variables in functions declare them sorted by size,
|
|
|
|
then in alphabetical order; multiple ones per line are okay.
|
2001-02-02 03:11:22 +00:00
|
|
|
If a line overflows reuse the type keyword.
|
1996-03-31 22:36:14 +00:00
|
|
|
.Pp
|
|
|
|
Be careful to not obfuscate the code by initializing variables in
|
2001-12-08 17:48:18 +00:00
|
|
|
the declarations.
|
|
|
|
Use this feature only thoughtfully.
|
2001-09-05 00:46:51 +00:00
|
|
|
DO NOT use function calls in initializers.
|
2001-02-01 16:38:02 +00:00
|
|
|
.Bd -literal
|
1997-05-27 10:00:08 +00:00
|
|
|
struct foo one, *two;
|
|
|
|
double three;
|
|
|
|
int *four, five;
|
|
|
|
char *six, seven, eight, nine, ten, eleven, twelve;
|
|
|
|
|
|
|
|
four = myfunction();
|
1996-03-31 22:36:14 +00:00
|
|
|
.Ed
|
|
|
|
.Pp
|
1997-05-27 10:00:08 +00:00
|
|
|
Do not declare functions inside other functions; ANSI C says that
|
|
|
|
such declarations have file scope regardless of the nesting of the
|
2001-12-08 17:48:18 +00:00
|
|
|
declaration.
|
|
|
|
Hiding file declarations in what appears to be a local
|
1997-05-27 10:00:08 +00:00
|
|
|
scope is undesirable and will elicit complaints from a good compiler.
|
|
|
|
.Pp
|
2001-12-08 17:48:18 +00:00
|
|
|
Casts and
|
|
|
|
.Ic sizeof Ns 's
|
|
|
|
are not followed by a space.
|
|
|
|
Note that
|
1997-05-27 10:00:08 +00:00
|
|
|
.Xr indent 1
|
|
|
|
does not understand this rule.
|
2002-07-25 00:30:24 +00:00
|
|
|
.Ic sizeof Ns 's
|
|
|
|
are written with parenthesis always.
|
|
|
|
The redundant parenthesis rules do not apply to
|
2002-08-13 14:52:41 +00:00
|
|
|
.Fn sizeof var
|
2002-07-25 00:30:24 +00:00
|
|
|
instances.
|
1996-07-17 12:32:18 +00:00
|
|
|
.Pp
|
2001-12-08 17:48:18 +00:00
|
|
|
.Dv NULL
|
|
|
|
is the preferred null pointer constant.
|
|
|
|
Use
|
|
|
|
.Dv NULL
|
|
|
|
instead of
|
|
|
|
.Vt ( "type *" ) Ns 0
|
|
|
|
or
|
|
|
|
.Vt ( "type *" ) Ns Dv NULL
|
|
|
|
in contexts where the compiler knows the
|
|
|
|
type, e.g., in assignments.
|
|
|
|
Use
|
|
|
|
.Vt ( "type *" ) Ns Dv NULL
|
|
|
|
in other contexts,
|
|
|
|
in particular for all function args.
|
|
|
|
(Casting is essential for
|
1999-08-02 04:00:33 +00:00
|
|
|
variadic args and is necessary for other args if the function prototype
|
1997-05-27 10:00:08 +00:00
|
|
|
might not be in scope.)
|
2001-12-08 17:48:18 +00:00
|
|
|
Test pointers against
|
|
|
|
.Dv NULL ,
|
|
|
|
e.g., use:
|
|
|
|
.Pp
|
2001-02-01 16:38:02 +00:00
|
|
|
.Bd -literal
|
1999-10-10 09:28:14 +00:00
|
|
|
(p = f()) == NULL
|
1996-03-31 22:36:14 +00:00
|
|
|
.Ed
|
|
|
|
.Pp
|
|
|
|
not:
|
2001-02-01 16:38:02 +00:00
|
|
|
.Bd -literal
|
1996-03-31 22:36:14 +00:00
|
|
|
!(p = f())
|
|
|
|
.Ed
|
|
|
|
.Pp
|
2001-12-08 17:48:18 +00:00
|
|
|
Do not use
|
|
|
|
.Ic \&!
|
2004-07-03 18:29:24 +00:00
|
|
|
for tests unless it is a boolean, e.g.\& use
|
2001-02-01 16:38:02 +00:00
|
|
|
.Bd -literal
|
1996-03-31 22:36:14 +00:00
|
|
|
if (*p == '\e0')
|
|
|
|
.Ed
|
|
|
|
.Pp
|
|
|
|
not
|
2001-02-01 16:38:02 +00:00
|
|
|
.Bd -literal
|
1996-03-31 22:36:14 +00:00
|
|
|
if (!*p)
|
|
|
|
.Ed
|
|
|
|
.Pp
|
2001-12-08 17:48:18 +00:00
|
|
|
Routines returning
|
|
|
|
.Vt "void *"
|
|
|
|
should not have their return values cast
|
1996-03-31 22:36:14 +00:00
|
|
|
to any pointer type.
|
|
|
|
.Pp
|
2001-12-08 17:48:18 +00:00
|
|
|
Values in
|
|
|
|
.Ic return
|
|
|
|
statements should be enclosed in parentheses.
|
2001-12-07 11:40:22 +00:00
|
|
|
.Pp
|
1996-03-31 22:36:14 +00:00
|
|
|
Use
|
1996-04-07 00:06:21 +00:00
|
|
|
.Xr err 3
|
|
|
|
or
|
|
|
|
.Xr warn 3 ,
|
2001-12-08 17:48:18 +00:00
|
|
|
do not roll your own.
|
2001-02-01 16:38:02 +00:00
|
|
|
.Bd -literal
|
1995-12-21 18:35:19 +00:00
|
|
|
if ((four = malloc(sizeof(struct foo))) == NULL)
|
1996-07-17 12:32:18 +00:00
|
|
|
err(1, (char *)NULL);
|
1995-12-21 18:35:19 +00:00
|
|
|
if ((six = (int *)overflow()) == NULL)
|
2001-07-22 11:47:15 +00:00
|
|
|
errx(1, "number overflowed");
|
1995-12-21 18:35:19 +00:00
|
|
|
return (eight);
|
1995-12-14 10:50:27 +00:00
|
|
|
}
|
1996-03-31 22:36:14 +00:00
|
|
|
.Ed
|
|
|
|
.Pp
|
1997-05-27 10:00:08 +00:00
|
|
|
Old-style function declarations look like this:
|
2001-02-01 16:38:02 +00:00
|
|
|
.Bd -literal
|
1997-05-27 10:00:08 +00:00
|
|
|
static char *
|
|
|
|
function(a1, a2, fl, a4)
|
|
|
|
int a1, a2; /* Declare ints, too, don't default them. */
|
|
|
|
float fl; /* Beware double vs. float prototype differences. */
|
|
|
|
int a4; /* List in order declared. */
|
1995-12-14 10:50:27 +00:00
|
|
|
{
|
1996-03-31 22:36:14 +00:00
|
|
|
.Ed
|
|
|
|
.Pp
|
1999-06-27 02:38:46 +00:00
|
|
|
Use ANSI function declarations unless you explicitly need K&R compatibility.
|
2001-04-22 02:00:39 +00:00
|
|
|
Long parameter lists are wrapped with a normal four space indent.
|
1997-05-27 10:00:08 +00:00
|
|
|
.Pp
|
1996-03-31 22:36:14 +00:00
|
|
|
Variable numbers of arguments should look like this.
|
2001-02-01 16:38:02 +00:00
|
|
|
.Bd -literal
|
1995-12-14 10:50:27 +00:00
|
|
|
#include <stdarg.h>
|
|
|
|
|
|
|
|
void
|
|
|
|
vaf(const char *fmt, ...)
|
|
|
|
{
|
1995-12-21 18:35:19 +00:00
|
|
|
va_list ap;
|
1997-05-27 10:00:08 +00:00
|
|
|
|
1995-12-21 18:35:19 +00:00
|
|
|
va_start(ap, fmt);
|
|
|
|
STUFF;
|
1997-05-27 10:00:08 +00:00
|
|
|
va_end(ap);
|
|
|
|
/* No return needed for void functions. */
|
1995-12-14 10:50:27 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
static void
|
|
|
|
usage()
|
1996-03-31 22:36:14 +00:00
|
|
|
{
|
|
|
|
/* Insert an empty line if the function has no local variables. */
|
|
|
|
.Ed
|
|
|
|
.Pp
|
|
|
|
Use
|
|
|
|
.Xr printf 3 ,
|
2001-12-08 17:48:18 +00:00
|
|
|
not
|
|
|
|
.Xr fputs 3 ,
|
|
|
|
.Xr puts 3 ,
|
|
|
|
.Xr putchar 3 ,
|
|
|
|
whatever; it is faster and usually cleaner, not
|
1996-03-31 22:36:14 +00:00
|
|
|
to mention avoiding stupid bugs.
|
|
|
|
.Pp
|
2001-12-08 17:48:18 +00:00
|
|
|
Usage statements should look like the manual pages
|
|
|
|
.Sx SYNOPSIS .
|
2000-07-16 20:46:43 +00:00
|
|
|
The usage statement should be structured in the following order:
|
2000-12-29 09:18:45 +00:00
|
|
|
.Bl -enum
|
2000-07-16 20:46:43 +00:00
|
|
|
.It
|
|
|
|
Options without operands come first,
|
|
|
|
in alphabetical order,
|
2000-07-18 14:41:01 +00:00
|
|
|
inside a single set of brackets
|
2001-12-08 17:48:18 +00:00
|
|
|
.Ql ( \&[
|
2000-07-18 14:41:01 +00:00
|
|
|
and
|
2001-12-08 17:48:18 +00:00
|
|
|
.Ql \&] ) .
|
2000-07-16 20:46:43 +00:00
|
|
|
.It
|
|
|
|
Options with operands come next,
|
|
|
|
also in alphabetical order,
|
|
|
|
with each option and its argument inside its own pair of brackets.
|
|
|
|
.It
|
|
|
|
Required arguments
|
2001-08-07 14:12:13 +00:00
|
|
|
(if any)
|
2000-07-16 20:46:43 +00:00
|
|
|
are next,
|
2001-12-08 17:48:18 +00:00
|
|
|
listed in the order they should be specified on the command line.
|
2000-07-16 20:46:43 +00:00
|
|
|
.It
|
|
|
|
Finally,
|
|
|
|
any optional arguments should be listed,
|
|
|
|
listed in the order they should be specified,
|
|
|
|
and all inside brackets.
|
|
|
|
.El
|
|
|
|
.Pp
|
|
|
|
A bar
|
2001-12-08 17:48:18 +00:00
|
|
|
.Pq Ql \&|
|
|
|
|
separates
|
|
|
|
.Dq either-or
|
|
|
|
options/arguments,
|
1996-03-31 22:36:14 +00:00
|
|
|
and multiple options/arguments which are specified together are
|
2000-07-16 20:46:43 +00:00
|
|
|
placed in a single set of brackets.
|
2001-12-08 17:48:18 +00:00
|
|
|
.Bd -literal -offset 4n
|
1999-12-16 10:02:20 +00:00
|
|
|
"usage: f [-aDde] [-b b_arg] [-m m_arg] req1 req2 [opt1 [opt2]]\en"
|
|
|
|
"usage: f [-a | -b] [-c [-dEe] [-n number]]\en"
|
1996-03-31 22:36:14 +00:00
|
|
|
.Ed
|
2001-02-01 16:38:02 +00:00
|
|
|
.Bd -literal
|
1995-12-21 18:35:19 +00:00
|
|
|
(void)fprintf(stderr, "usage: f [-ab]\en");
|
2000-10-28 10:02:23 +00:00
|
|
|
exit(EX_USAGE);
|
1995-12-14 10:50:27 +00:00
|
|
|
}
|
|
|
|
.Ed
|
1996-03-31 22:36:14 +00:00
|
|
|
.Pp
|
2001-07-19 18:03:43 +00:00
|
|
|
Note that the manual page options description should list the options in
|
|
|
|
pure alphabetical order.
|
2001-08-07 14:12:13 +00:00
|
|
|
That is, without regard to whether an option takes arguments or not.
|
2001-07-19 18:03:43 +00:00
|
|
|
The alphabetical ordering should take into account the case ordering
|
|
|
|
shown above.
|
|
|
|
.Pp
|
2001-12-08 17:48:18 +00:00
|
|
|
New core kernel code should be reasonably compliant with the
|
|
|
|
.Nm
|
|
|
|
guides.
|
1997-05-27 10:00:08 +00:00
|
|
|
The guidelines for third-party maintained modules and device drivers are more
|
1999-06-27 02:38:46 +00:00
|
|
|
relaxed but at a minimum should be internally consistent with their style.
|
1997-05-27 10:00:08 +00:00
|
|
|
.Pp
|
|
|
|
Stylistic changes (including whitespace changes) are hard on the source
|
2001-12-08 17:48:18 +00:00
|
|
|
repository and are to be avoided without good reason.
|
|
|
|
Code that is approximately
|
2001-08-07 14:12:13 +00:00
|
|
|
.Fx
|
|
|
|
KNF
|
2001-12-08 17:48:18 +00:00
|
|
|
.Nm
|
2000-01-15 16:34:07 +00:00
|
|
|
compliant in the repository must not diverge from compliance.
|
1999-01-30 04:17:14 +00:00
|
|
|
.Pp
|
|
|
|
Whenever possible, code should be run through a code checker
|
2000-11-13 16:18:46 +00:00
|
|
|
(e.g.,
|
|
|
|
.Xr lint 1
|
|
|
|
or
|
2001-12-08 17:48:18 +00:00
|
|
|
.Nm gcc Fl Wall )
|
|
|
|
and produce minimal warnings.
|
1996-03-31 22:36:14 +00:00
|
|
|
.Sh SEE ALSO
|
1997-05-27 10:00:08 +00:00
|
|
|
.Xr indent 1 ,
|
2000-11-13 16:18:46 +00:00
|
|
|
.Xr lint 1 ,
|
1996-03-31 22:36:14 +00:00
|
|
|
.Xr err 3 ,
|
1996-12-26 16:16:37 +00:00
|
|
|
.Xr sysexits 3 ,
|
2003-04-26 15:37:39 +00:00
|
|
|
.Xr warn 3 ,
|
|
|
|
.Xr style.Makefile 5
|
1995-12-14 10:50:27 +00:00
|
|
|
.Sh HISTORY
|
2001-12-08 17:48:18 +00:00
|
|
|
This man page is largely based on the
|
|
|
|
.Pa src/admin/style/style
|
|
|
|
file from the
|
2001-08-14 10:01:54 +00:00
|
|
|
.Bx 4.4 Lite2
|
2001-10-23 17:40:37 +00:00
|
|
|
release, with occasional updates to reflect the current practice and
|
1997-05-27 10:00:08 +00:00
|
|
|
desire of the
|
2000-11-14 11:20:58 +00:00
|
|
|
.Fx
|
1997-03-21 20:14:15 +00:00
|
|
|
project.
|