strerror.c revision 290001 
1/*
2 * Copyright (C) 2004, 2005, 2007, 2009  Internet Systems Consortium, Inc. ("ISC")
3 * Copyright (C) 2001  Internet Software Consortium.
4 *
5 * Permission to use, copy, modify, and/or distribute this software for any
6 * purpose with or without fee is hereby granted, provided that the above
7 * copyright notice and this permission notice appear in all copies.
8 *
9 * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
10 * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
11 * AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
12 * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
13 * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
14 * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
15 * PERFORMANCE OF THIS SOFTWARE.
16 */
17
18/* $Id: strerror.c,v 1.10 2009/02/16 23:48:04 tbox Exp $ */
19
20/*! \file */
21
22#include <config.h>
23
24#include <stdio.h>
25#include <string.h>
26
27#include <isc/mutex.h>
28#include <isc/once.h>
29#include <isc/print.h>
30#include <isc/strerror.h>
31#include <isc/util.h>
32
33#include "l_stdlib.h"		/* NTP local change */
34
35#ifdef HAVE_STRERROR
36/*%
37 * We need to do this this way for profiled locks.
38 */
39static isc_mutex_t isc_strerror_lock;
40static void init_lock(void) {
41	RUNTIME_CHECK(isc_mutex_init(&isc_strerror_lock) == ISC_R_SUCCESS);
42}
43#else
44extern const char * const sys_errlist[];
45extern const int sys_nerr;
46#endif
47
48void
49isc__strerror(int num, char *buf, size_t size) {
50#ifdef HAVE_STRERROR
51	char *msg;
52	unsigned int unum = (unsigned int)num;
53	static isc_once_t once = ISC_ONCE_INIT;
54
55	REQUIRE(buf != NULL);
56
57	RUNTIME_CHECK(isc_once_do(&once, init_lock) == ISC_R_SUCCESS);
58
59	LOCK(&isc_strerror_lock);
60	msg = strerror(num);
61	if (msg != NULL)
62		snprintf(buf, size, "%s", msg);
63	else
64		snprintf(buf, size, "Unknown error: %u", unum);
65	UNLOCK(&isc_strerror_lock);
66#else
67	unsigned int unum = (unsigned int)num;
68
69	REQUIRE(buf != NULL);
70
71	if (num >= 0 && num < sys_nerr)
72		snprintf(buf, size, "%s", sys_errlist[num]);
73	else
74		snprintf(buf, size, "Unknown error: %u", unum);
75#endif
76}
77