string/FreeBSD/strerror.c

   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)
  31 static 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
  82 int
  83 strerror_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
 124 extern char *__strerror_ebuf;
 125 #endif /* !BUILDING_VARIANT */
 126
 127 char *
 128 strerror(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 }