1/*-
2 * Copyright (c) 1988, 1993
3 *	The Regents of the University of California.  All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 * 4. Neither the name of the University nor the names of its contributors
14 *    may be used to endorse or promote products derived from this software
15 *    without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 */
29
30#if defined(LIBC_SCCS) && !defined(lint)
31static char sccsid[] = "@(#)strerror.c	8.1 (Berkeley) 6/4/93";
32#endif /* LIBC_SCCS and not lint */
33#include <sys/cdefs.h>
34__FBSDID("$FreeBSD: src/lib/libc/string/strerror.c,v 1.16 2007/01/09 00:28:12 imp Exp $");
35
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#include <stdlib.h>
45
46#define	UPREFIX		"Unknown error"
47
48/*
49 * Define a buffer size big enough to describe a 64-bit signed integer
50 * converted to ASCII decimal (19 bytes), with an optional leading sign
51 * (1 byte); finally, we get the prefix, delimiter (": ") and a trailing
52 * NUL from UPREFIX.
53 */
54#define	EBUFSIZE	(20 + 2 + sizeof(UPREFIX))
55
56#ifndef BUILDING_VARIANT
57/*
58 * Doing this by hand instead of linking with stdio(3) avoids bloat for
59 * statically linked binaries.
60 */
61__private_extern__ void
62__errstr(int num, char *uprefix, char *buf, size_t len)
63{
64	char *t;
65	unsigned int uerr;
66	char tmp[EBUFSIZE];
67
68	t = tmp + sizeof(tmp);
69	*--t = '\0';
70	uerr = (num >= 0) ? num : -num;
71	do {
72		*--t = "0123456789"[uerr % 10];
73	} while (uerr /= 10);
74	if (num < 0)
75		*--t = '-';
76	*--t = ' ';
77	*--t = ':';
78	strlcpy(buf, uprefix, len);
79	strlcat(buf, t, len);
80}
81
82int
83strerror_r(int errnum, char *strerrbuf, size_t buflen)
84{
85	int retval = 0;
86#if defined(NLS)
87	int saved_errno = errno;
88	nl_catd catd;
89	catd = catopen("libc", NL_CAT_LOCALE);
90#endif
91
92	if (errnum < 0 || errnum >= 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, sys_errlist[errnum]),
105#else
106			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__private_extern__ char *__strerror_ebuf = NULL;
121#else /* BUILDING_VARIANT */
122__private_extern__ void __errstr(int, char *, size_t);
123
124extern char *__strerror_ebuf;
125#endif /* !BUILDING_VARIANT */
126
127char *
128strerror(int num)
129{
130	// Dynamically allocate a big buffer to receive the text then shrink it
131	// down to the actual size needed.
132	size_t ebufsiz = NL_TEXTMAX;
133
134	if (__strerror_ebuf == NULL) {
135		__strerror_ebuf = calloc(1, ebufsiz);
136		if (__strerror_ebuf == NULL) {
137			return NULL;
138		}
139	}
140
141	if (strerror_r(num, __strerror_ebuf, ebufsiz) != 0) {
142#if !__DARWIN_UNIX03
143		errno = EINVAL;
144#endif
145	}
146	return __strerror_ebuf;
147}
148