xref: /freebsd/lib/libc/string/strerror.c (revision bdcbfde31e8e9b343f113a1956384bdf30d1ed62)
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 "errlst.h"
42 #include "../locale/xlocale_private.h"
43 #include "libc_private.h"
44 
45 /*
46  * Define buffer big enough to contain delimiter (": ", 2 bytes),
47  * 64-bit signed integer converted to ASCII decimal (19 bytes) with
48  * optional leading sign (1 byte), and a trailing NUL.
49  */
50 #define	EBUFSIZE	(2 + 19 + 1 + 1)
51 
52 /*
53  * Doing this by hand instead of linking with stdio(3) avoids bloat for
54  * statically linked binaries.
55  */
56 static void
57 errstr(int num, const char *uprefix, char *buf, size_t len)
58 {
59 	char *t;
60 	unsigned int uerr;
61 	char tmp[EBUFSIZE];
62 
63 	t = tmp + sizeof(tmp);
64 	*--t = '\0';
65 	uerr = (num >= 0) ? num : -num;
66 	do {
67 		*--t = "0123456789"[uerr % 10];
68 	} while (uerr /= 10);
69 	if (num < 0)
70 		*--t = '-';
71 	*--t = ' ';
72 	*--t = ':';
73 	strlcpy(buf, uprefix, len);
74 	strlcat(buf, t, len);
75 }
76 
77 static int
78 strerror_rl(int errnum, char *strerrbuf, size_t buflen, locale_t locale)
79 {
80 	int retval = 0;
81 #if defined(NLS)
82 	int saved_errno = errno;
83 	nl_catd catd;
84 
85 	catd = __catopen_l("libc", NL_CAT_LOCALE, locale);
86 #endif
87 
88 	if (errnum < 0 || errnum >= __hidden_sys_nerr) {
89 		errstr(errnum,
90 #if defined(NLS)
91 		    catgets(catd, 1, 0xffff, __uprefix),
92 #else
93 		    __uprefix,
94 #endif
95 		   strerrbuf, buflen);
96 		retval = EINVAL;
97 	} else {
98 		if (strlcpy(strerrbuf,
99 #if defined(NLS)
100 		    catgets(catd, 1, errnum, __hidden_sys_errlist[errnum]),
101 #else
102 		    __hidden_sys_errlist[errnum],
103 #endif
104 		    buflen) >= buflen)
105 			retval = ERANGE;
106 	}
107 
108 #if defined(NLS)
109 	catclose(catd);
110 	errno = saved_errno;
111 #endif
112 
113 	return (retval);
114 }
115 
116 int
117 strerror_r(int errnum, char *strerrbuf, size_t buflen)
118 {
119 	return (strerror_rl(errnum, strerrbuf, buflen, __get_locale()));
120 }
121 
122 char *
123 strerror_l(int num, locale_t locale)
124 {
125 	static _Thread_local char ebuf[NL_TEXTMAX];
126 
127 	if (strerror_rl(num, ebuf, sizeof(ebuf), locale) != 0)
128 		errno = EINVAL;
129 	return (ebuf);
130 }
131 
132 char *
133 strerror(int num)
134 {
135 	static char ebuf[NL_TEXTMAX];
136 
137 	if (strerror_rl(num, ebuf, sizeof(ebuf), __get_locale()) != 0)
138 		errno = EINVAL;
139 	return (ebuf);
140 }
141