xref: /freebsd/lib/libc/string/strerror.c (revision 22cf89c938886d14f5796fc49f9f020c23ea8eaf)
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 #if defined(NLS)
37 #include <nl_types.h>
38 #endif
39 
40 #include <limits.h>
41 #include <errno.h>
42 #include <string.h>
43 #include <stdio.h>
44 
45 #include "errlst.h"
46 #include "../locale/xlocale_private.h"
47 #include "libc_private.h"
48 
49 /*
50  * Define buffer big enough to contain delimiter (": ", 2 bytes),
51  * 64-bit signed integer converted to ASCII decimal (19 bytes) with
52  * optional leading sign (1 byte), and a trailing NUL.
53  */
54 #define	EBUFSIZE	(2 + 19 + 1 + 1)
55 
56 /*
57  * Doing this by hand instead of linking with stdio(3) avoids bloat for
58  * statically linked binaries.
59  */
60 static void
61 errstr(int num, const char *uprefix, char *buf, size_t len)
62 {
63 	char *t;
64 	unsigned int uerr;
65 	char tmp[EBUFSIZE];
66 
67 	t = tmp + sizeof(tmp);
68 	*--t = '\0';
69 	uerr = (num >= 0) ? num : -num;
70 	do {
71 		*--t = "0123456789"[uerr % 10];
72 	} while (uerr /= 10);
73 	if (num < 0)
74 		*--t = '-';
75 	*--t = ' ';
76 	*--t = ':';
77 	strlcpy(buf, uprefix, len);
78 	strlcat(buf, t, len);
79 }
80 
81 static int
82 strerror_rl(int errnum, char *strerrbuf, size_t buflen, locale_t locale)
83 {
84 	int retval = 0;
85 #if defined(NLS)
86 	int saved_errno = errno;
87 	nl_catd catd;
88 
89 	catd = __catopen_l("libc", NL_CAT_LOCALE, locale);
90 #endif
91 
92 	if (errnum < 0 || errnum >= __hidden_sys_nerr) {
93 		errstr(errnum,
94 #if defined(NLS)
95 		    catgets(catd, 1, 0xffff, __uprefix),
96 #else
97 		    __uprefix,
98 #endif
99 		   strerrbuf, buflen);
100 		retval = EINVAL;
101 	} else {
102 		if (strlcpy(strerrbuf,
103 #if defined(NLS)
104 		    catgets(catd, 1, errnum, __hidden_sys_errlist[errnum]),
105 #else
106 		    __hidden_sys_errlist[errnum],
107 #endif
108 		    buflen) >= buflen)
109 			retval = ERANGE;
110 	}
111 
112 #if defined(NLS)
113 	catclose(catd);
114 	errno = saved_errno;
115 #endif
116 
117 	return (retval);
118 }
119 
120 int
121 strerror_r(int errnum, char *strerrbuf, size_t buflen)
122 {
123 	return (strerror_rl(errnum, strerrbuf, buflen, __get_locale()));
124 }
125 
126 char *
127 strerror_l(int num, locale_t locale)
128 {
129 	static _Thread_local char ebuf[NL_TEXTMAX];
130 
131 	if (strerror_rl(num, ebuf, sizeof(ebuf), locale) != 0)
132 		errno = EINVAL;
133 	return (ebuf);
134 }
135 
136 char *
137 strerror(int num)
138 {
139 	static char ebuf[NL_TEXTMAX];
140 
141 	if (strerror_rl(num, ebuf, sizeof(ebuf), __get_locale()) != 0)
142 		errno = EINVAL;
143 	return (ebuf);
144 }
145