138 lines
4.0 KiB
Groff
138 lines
4.0 KiB
Groff
.\" $NetBSD: _DIAGASSERT.3,v 1.7 2007/01/22 11:57:44 jdc Exp $
|
|
.\"
|
|
.\" Copyright (c) 2001 The NetBSD Foundation, Inc.
|
|
.\" All rights reserved.
|
|
.\"
|
|
.\" This code is derived from software contributed to The NetBSD Foundation
|
|
.\" by Luke Mewburn.
|
|
.\"
|
|
.\" 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 the NetBSD
|
|
.\" Foundation, Inc. and its contributors.
|
|
.\" 4. Neither the name of The NetBSD Foundation 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 NETBSD FOUNDATION, INC. 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 FOUNDATION 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 January 22, 2007
|
|
.Dt _DIAGASSERT 3
|
|
.Os
|
|
.Sh NAME
|
|
.Nm _DIAGASSERT
|
|
.Nd expression verification macro
|
|
.Sh SYNOPSIS
|
|
.In assert.h
|
|
.Fn _DIAGASSERT expression
|
|
.Sh DESCRIPTION
|
|
The
|
|
.Fn _DIAGASSERT
|
|
macro tests the given
|
|
.Ar expression
|
|
and if it is false, one or more of the following may occur:
|
|
.Bl -bullet -offset indent
|
|
.It
|
|
a diagnostic message may be logged to the system logger with
|
|
.Xr syslog 3 .
|
|
This is default behaviour.
|
|
.It
|
|
a diagnostic message may be printed to the
|
|
.Dv stderr
|
|
stream.
|
|
.It
|
|
the calling process will be terminated by calling
|
|
.Xr abort 3 .
|
|
.El
|
|
.Pp
|
|
This behaviour may be changed by setting the
|
|
.Ev LIBC_DIAGASSERT
|
|
environment variable (see below).
|
|
.Pp
|
|
The diagnostic message consists of the text of the expression,
|
|
the name of the source file, the line number and the enclosing
|
|
function.
|
|
.Pp
|
|
If
|
|
.Ar expression
|
|
is true,
|
|
the
|
|
.Fn _DIAGASSERT
|
|
macro does nothing.
|
|
.Pp
|
|
The
|
|
.Fn _DIAGASSERT
|
|
macro is not compiled in by default, and will only be compiled in with the
|
|
.Xr cc 1
|
|
option
|
|
.Fl D_DIAGNOSTIC .
|
|
.Pp
|
|
This macro is used in the various system libraries such as the
|
|
.Lb libc
|
|
to ensure that various library calls are invoked with valid arguments.
|
|
.Sh ENVIRONMENT
|
|
The
|
|
.Ev LIBC_DIAGASSERT
|
|
environment variable can be used to modify the default behaviour of
|
|
logging the assertion to the system logger.
|
|
.Pp
|
|
.Ev LIBC_DIAGASSERT
|
|
may be set to one or more of the following characters:
|
|
.Bl -tag -width xxx -offset indent
|
|
.It a
|
|
.Xr abort 3
|
|
once any assertion messages have been logged and/or printed.
|
|
.It A
|
|
Opposite of
|
|
.Dq a .
|
|
.It e
|
|
Print the assertion message to the
|
|
.Dv stderr
|
|
stream.
|
|
.It E
|
|
Opposite of
|
|
.Dq e .
|
|
.It l
|
|
Log the assertion message with
|
|
.Xr syslog 3
|
|
to the facility
|
|
.Dv user.debug .
|
|
.It L
|
|
Opposite of
|
|
.Dq l .
|
|
.El
|
|
.Sh DIAGNOSTICS
|
|
The diagnostic message has the following format:
|
|
.Bd -literal -offset indent
|
|
"assertion \e"%s\e" failed: file \e"%s\e", line %d, function \e"%s\e"\en",
|
|
"expression", __FILE__, __LINE__, __func__
|
|
.Ed
|
|
.Sh SEE ALSO
|
|
.Xr cc 1 ,
|
|
.Xr abort 3 ,
|
|
.Xr assert 3 ,
|
|
.Xr syslog 3
|
|
.Sh HISTORY
|
|
The
|
|
.Nm _DIAGASSERT
|
|
macro appeared in
|
|
.Nx 1.5 .
|