strace/error_prints.c
Dmitry V. Levin b93d52fe3d Change the license of strace to LGPL-2.1-or-later
strace is now provided under the terms of the GNU Lesser General
Public License version 2.1 or later, see COPYING for more details.

strace test suite is now provided under the terms of the GNU General
Public License version 2 or later, see tests/COPYING for more details.
2018-12-10 00:00:00 +00:00

109 lines
2.0 KiB
C

/*
* Copyright (c) 1999-2018 The strace developers.
* All rights reserved.
*
* SPDX-License-Identifier: LGPL-2.1-or-later
*/
#ifdef HAVE_CONFIG_H
# include "config.h"
#endif
#include <errno.h>
#include <stdarg.h>
#include <string.h>
#include <stdio.h>
#include <stdlib.h>
#include "error_prints.h"
#ifndef HAVE_PROGRAM_INVOCATION_NAME
extern char *program_invocation_name;
#endif
static void
verror_msg(int err_no, const char *fmt, va_list p)
{
char *msg;
fflush(NULL);
/* We want to print entire message with single fprintf to ensure
* message integrity if stderr is shared with other programs.
* Thus we use vasprintf + single fprintf.
*/
msg = NULL;
if (vasprintf(&msg, fmt, p) >= 0) {
if (err_no)
fprintf(stderr, "%s: %s: %s\n",
program_invocation_name, msg, strerror(err_no));
else
fprintf(stderr, "%s: %s\n",
program_invocation_name, msg);
free(msg);
} else {
/* malloc in vasprintf failed, try it without malloc */
fprintf(stderr, "%s: ", program_invocation_name);
vfprintf(stderr, fmt, p);
if (err_no)
fprintf(stderr, ": %s\n", strerror(err_no));
else
putc('\n', stderr);
}
/* We don't switch stderr to buffered, thus fprintf(stderr)
* always flushes its output and this is not necessary: */
/* fflush(stderr); */
}
void
error_msg(const char *fmt, ...)
{
va_list p;
va_start(p, fmt);
verror_msg(0, fmt, p);
va_end(p);
}
void
error_msg_and_die(const char *fmt, ...)
{
va_list p;
va_start(p, fmt);
verror_msg(0, fmt, p);
va_end(p);
die();
}
void
error_msg_and_help(const char *fmt, ...)
{
if (fmt != NULL) {
va_list p;
va_start(p, fmt);
verror_msg(0, fmt, p);
va_end(p);
}
fprintf(stderr, "Try '%s -h' for more information.\n",
program_invocation_name);
die();
}
void
perror_msg(const char *fmt, ...)
{
va_list p;
va_start(p, fmt);
verror_msg(errno, fmt, p);
va_end(p);
}
void
perror_msg_and_die(const char *fmt, ...)
{
va_list p;
va_start(p, fmt);
verror_msg(errno, fmt, p);
va_end(p);
die();
}