xref: /freebsd/lib/libc/string/strerror.c (revision c66ec88fed842fbaad62c30d510644ceb7bd2d71)
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[] = "@(#)strerror.c	8.1 (Berkeley) 6/4/93";
34 #endif /* LIBC_SCCS and not lint */
35 #include <sys/cdefs.h>
36 __FBSDID("$FreeBSD$");
37 
38 #if defined(NLS)
39 #include <nl_types.h>
40 #endif
41 
42 #include <limits.h>
43 #include <errno.h>
44 #include <string.h>
45 #include <stdio.h>
46 
47 #include "errlst.h"
48 #include "../locale/xlocale_private.h"
49 #include "libc_private.h"
50 
51 /*
52  * Define buffer big enough to contain delimiter (": ", 2 bytes),
53  * 64-bit signed integer converted to ASCII decimal (19 bytes) with
54  * optional leading sign (1 byte), and a trailing NUL.
55  */
56 #define	EBUFSIZE	(2 + 19 + 1 + 1)
57 
58 /*
59  * Doing this by hand instead of linking with stdio(3) avoids bloat for
60  * statically linked binaries.
61  */
62 static void
63 errstr(int num, const char *uprefix, char *buf, size_t len)
64 {
65 	char *t;
66 	unsigned int uerr;
67 	char tmp[EBUFSIZE];
68 
69 	t = tmp + sizeof(tmp);
70 	*--t = '\0';
71 	uerr = (num >= 0) ? num : -num;
72 	do {
73 		*--t = "0123456789"[uerr % 10];
74 	} while (uerr /= 10);
75 	if (num < 0)
76 		*--t = '-';
77 	*--t = ' ';
78 	*--t = ':';
79 	strlcpy(buf, uprefix, len);
80 	strlcat(buf, t, len);
81 }
82 
83 static int
84 strerror_rl(int errnum, char *strerrbuf, size_t buflen, locale_t locale)
85 {
86 	int retval = 0;
87 #if defined(NLS)
88 	int saved_errno = errno;
89 	nl_catd catd;
90 
91 	catd = __catopen_l("libc", NL_CAT_LOCALE, locale);
92 #endif
93 
94 	if (errnum < 0 || errnum >= __hidden_sys_nerr) {
95 		errstr(errnum,
96 #if defined(NLS)
97 		    catgets(catd, 1, 0xffff, __uprefix),
98 #else
99 		    __uprefix,
100 #endif
101 		   strerrbuf, buflen);
102 		retval = EINVAL;
103 	} else {
104 		if (strlcpy(strerrbuf,
105 #if defined(NLS)
106 		    catgets(catd, 1, errnum, __hidden_sys_errlist[errnum]),
107 #else
108 		    __hidden_sys_errlist[errnum],
109 #endif
110 		    buflen) >= buflen)
111 			retval = ERANGE;
112 	}
113 
114 #if defined(NLS)
115 	catclose(catd);
116 	errno = saved_errno;
117 #endif
118 
119 	return (retval);
120 }
121 
122 int
123 strerror_r(int errnum, char *strerrbuf, size_t buflen)
124 {
125 	return (strerror_rl(errnum, strerrbuf, buflen, __get_locale()));
126 }
127 
128 char *
129 strerror_l(int num, locale_t locale)
130 {
131 #ifndef __NO_TLS
132 	static _Thread_local char ebuf[NL_TEXTMAX];
133 
134 	if (strerror_rl(num, ebuf, sizeof(ebuf), locale) != 0)
135 		errno = EINVAL;
136 	return (ebuf);
137 #else
138 	errno = ENOTSUP;
139 	return (NULL);
140 #endif
141 }
142 
143 char *
144 strerror(int num)
145 {
146 	static char ebuf[NL_TEXTMAX];
147 
148 	if (strerror_rl(num, ebuf, sizeof(ebuf), __get_locale()) != 0)
149 		errno = EINVAL;
150 	return (ebuf);
151 }
152