xref: /freebsd/lib/libc/string/strerror.c (revision a64729f5077d77e13b9497cb33ecb3c82e606ee8)
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(NLS)
33 #include <nl_types.h>
34 #endif
35 
36 #include <limits.h>
37 #include <errno.h>
38 #include <string.h>
39 #include <stdio.h>
40 
41 #include <ssp/ssp.h>
42 
43 #include "errlst.h"
44 #include "../locale/xlocale_private.h"
45 #include "libc_private.h"
46 
47 /*
48  * Define buffer big enough to contain delimiter (": ", 2 bytes),
49  * 64-bit signed integer converted to ASCII decimal (19 bytes) with
50  * optional leading sign (1 byte), and a trailing NUL.
51  */
52 #define	EBUFSIZE	(2 + 19 + 1 + 1)
53 
54 /*
55  * Doing this by hand instead of linking with stdio(3) avoids bloat for
56  * statically linked binaries.
57  */
58 static void
59 errstr(int num, const char *uprefix, char *buf, size_t len)
60 {
61 	char *t;
62 	unsigned int uerr;
63 	char tmp[EBUFSIZE];
64 
65 	t = tmp + sizeof(tmp);
66 	*--t = '\0';
67 	uerr = (num >= 0) ? num : -num;
68 	do {
69 		*--t = "0123456789"[uerr % 10];
70 	} while (uerr /= 10);
71 	if (num < 0)
72 		*--t = '-';
73 	*--t = ' ';
74 	*--t = ':';
75 	strlcpy(buf, uprefix, len);
76 	strlcat(buf, t, len);
77 }
78 
79 int
80 __strerror_rl(int errnum, char *strerrbuf, size_t buflen, locale_t locale)
81 {
82 	int retval = 0;
83 #if defined(NLS)
84 	int saved_errno = errno;
85 	nl_catd catd;
86 
87 	catd = __catopen_l("libc", NL_CAT_LOCALE, locale);
88 #endif
89 
90 	if (errnum < 0 || errnum >= __hidden_sys_nerr) {
91 		errstr(errnum,
92 #if defined(NLS)
93 		    catgets(catd, 1, 0xffff, __uprefix),
94 #else
95 		    __uprefix,
96 #endif
97 		   strerrbuf, buflen);
98 		retval = EINVAL;
99 	} else {
100 		if (strlcpy(strerrbuf,
101 #if defined(NLS)
102 		    catgets(catd, 1, errnum, __hidden_sys_errlist[errnum]),
103 #else
104 		    __hidden_sys_errlist[errnum],
105 #endif
106 		    buflen) >= buflen)
107 			retval = ERANGE;
108 	}
109 
110 #if defined(NLS)
111 	catclose(catd);
112 	errno = saved_errno;
113 #endif
114 
115 	return (retval);
116 }
117 
118 int
119 __ssp_real(strerror_r)(int errnum, char *strerrbuf, size_t buflen)
120 {
121 	return (__strerror_rl(errnum, strerrbuf, buflen, __get_locale()));
122 }
123 
124 char *
125 strerror_l(int num, locale_t locale)
126 {
127 	static _Thread_local char ebuf[NL_TEXTMAX];
128 
129 	if (__strerror_rl(num, ebuf, sizeof(ebuf), locale) != 0)
130 		errno = EINVAL;
131 	return (ebuf);
132 }
133 
134 char *
135 strerror(int num)
136 {
137 	static char ebuf[NL_TEXTMAX];
138 
139 	if (__strerror_rl(num, ebuf, sizeof(ebuf), __get_locale()) != 0)
140 		errno = EINVAL;
141 	return (ebuf);
142 }
143