xref: /freebsd/lib/libc/stdio/perror.c (revision ca6a6373bdaed010d6cbfb27f7249ae96009409d)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1988, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 #if defined(LIBC_SCCS) && !defined(lint)
33 static char sccsid[] = "@(#)perror.c	8.1 (Berkeley) 6/4/93";
34 #endif /* LIBC_SCCS and not lint */
35 #include "namespace.h"
36 #include <sys/types.h>
37 #include <sys/uio.h>
38 #include <unistd.h>
39 #include <errno.h>
40 #include <limits.h>
41 #include <stdio.h>
42 #include <string.h>
43 #include "un-namespace.h"
44 #include "libc_private.h"
45 #include "local.h"
46 
47 void
48 perror(const char *s)
49 {
50 	char msgbuf[NL_TEXTMAX];
51 	struct iovec *v;
52 	struct iovec iov[4];
53 
54 	v = iov;
55 	if (s != NULL && *s != '\0') {
56 		v->iov_base = (char *)s;
57 		v->iov_len = strlen(s);
58 		v++;
59 		v->iov_base = ": ";
60 		v->iov_len = 2;
61 		v++;
62 	}
63 	strerror_r(errno, msgbuf, sizeof(msgbuf));
64 	v->iov_base = msgbuf;
65 	v->iov_len = strlen(v->iov_base);
66 	v++;
67 	v->iov_base = "\n";
68 	v->iov_len = 1;
69 	FLOCKFILE_CANCELSAFE(stderr);
70 	__sflush(stderr);
71 	(void)_writev(stderr->_file, iov, (v - iov) + 1);
72 	stderr->_flags &= ~__SOFF;
73 	FUNLOCKFILE_CANCELSAFE();
74 }
75