freebsd-skq/bin/sh/error.c
2010-08-13 13:36:18 +00:00

190 lines
4.9 KiB
C

/*-
* Copyright (c) 1991, 1993
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Kenneth Almquist.
*
* 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.
* 4. 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.
*/
#ifndef lint
#if 0
static char sccsid[] = "@(#)error.c 8.2 (Berkeley) 5/4/95";
#endif
#endif /* not lint */
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
/*
* Errors and exceptions.
*/
#include "shell.h"
#include "main.h"
#include "options.h"
#include "output.h"
#include "error.h"
#include "nodes.h" /* show.h needs nodes.h */
#include "show.h"
#include "trap.h"
#include <signal.h>
#include <stdlib.h>
#include <unistd.h>
#include <errno.h>
/*
* Code to handle exceptions in C.
*/
struct jmploc *handler;
volatile sig_atomic_t exception;
volatile sig_atomic_t suppressint;
volatile sig_atomic_t intpending;
char *commandname;
static void exverror(int, const char *, va_list) __printf0like(2, 0) __dead2;
/*
* Called to raise an exception. Since C doesn't include exceptions, we
* just do a longjmp to the exception handler. The type of exception is
* stored in the global variable "exception".
*
* Interrupts are disabled; they should be reenabled when the exception is
* caught.
*/
void
exraise(int e)
{
INTOFF;
if (handler == NULL)
abort();
exception = e;
longjmp(handler->loc, 1);
}
/*
* Called from trap.c when a SIGINT is received. (If the user specifies
* that SIGINT is to be trapped or ignored using the trap builtin, then
* this routine is not called.) Suppressint is nonzero when interrupts
* are held using the INTOFF macro. If SIGINTs are not suppressed and
* the shell is not a root shell, then we want to be terminated if we
* get here, as if we were terminated directly by a SIGINT. Arrange for
* this here.
*/
void
onint(void)
{
sigset_t sigs;
/*
* The !in_dotrap here is safe. The only way we can arrive here
* with in_dotrap set is that a trap handler set SIGINT to SIG_DFL
* and killed itself.
*/
if (suppressint && !in_dotrap) {
intpending++;
return;
}
intpending = 0;
sigemptyset(&sigs);
sigprocmask(SIG_SETMASK, &sigs, NULL);
/*
* This doesn't seem to be needed, since main() emits a newline.
*/
#if 0
if (tcgetpgrp(0) == getpid())
write(STDERR_FILENO, "\n", 1);
#endif
if (rootshell && iflag)
exraise(EXINT);
else {
signal(SIGINT, SIG_DFL);
kill(getpid(), SIGINT);
}
}
/*
* Exverror is called to raise the error exception. If the first argument
* is not NULL then error prints an error message using printf style
* formatting. It then raises the error exception.
*/
static void
exverror(int cond, const char *msg, va_list ap)
{
/*
* An interrupt trumps an error. Certain places catch error
* exceptions or transform them to a plain nonzero exit code
* in child processes, and if an error exception can be handled,
* an interrupt can be handled as well.
*
* exraise() will disable interrupts for the exception handler.
*/
FORCEINTON;
#ifdef DEBUG
if (msg)
TRACE(("exverror(%d, \"%s\") pid=%d\n", cond, msg, getpid()));
else
TRACE(("exverror(%d, NULL) pid=%d\n", cond, getpid()));
#endif
if (msg) {
if (commandname)
outfmt(out2, "%s: ", commandname);
doformat(out2, msg, ap);
out2c('\n');
}
flushall();
exraise(cond);
}
void
error(const char *msg, ...)
{
va_list ap;
va_start(ap, msg);
exverror(EXERROR, msg, ap);
va_end(ap);
}
void
exerror(int cond, const char *msg, ...)
{
va_list ap;
va_start(ap, msg);
exverror(cond, msg, ap);
va_end(ap);
}