external/bsd/bind/dist/contrib/nslint-2.1a3/strerror.c

   1 /*      $NetBSD$        */
   2
   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. All advertising materials mentioning features or use of this software
  16  *    must display the following acknowledgement:
  17  *      This product includes software developed by the University of
  18  *      California, Berkeley and its contributors.
  19  * 4. Neither the name of the University nor the names of its contributors
  20  *    may be used to endorse or promote products derived from this software
  21  *    without specific prior written permission.
  22  *
  23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  33  * SUCH DAMAGE.
  34  */
  35
  36 #if defined(LIBC_SCCS) && !defined(lint)
  37 static const char sccsid[] = "@(#)strerror.c    8.1 (Berkeley) 6/4/93";
  38 #endif /* LIBC_SCCS and not lint */
  39
  40 #include <sys/types.h>
  41
  42 #include <string.h>
  43
  44 #include "gnuc.h"
  45 #ifdef HAVE_OS_PROTO_H
  46 #include "os-proto.h"
  47 #endif
  48
  49 char *
  50 strerror(num)
  51         int num;
  52 {
  53         extern int sys_nerr;
  54         extern char *sys_errlist[];
  55 #define UPREFIX "Unknown error: "
  56         static char ebuf[40] = UPREFIX;         /* 64-bit number + slop */
  57         register unsigned int errnum;
  58         register char *p, *t;
  59         char tmp[40];
  60
  61         errnum = num;                           /* convert to unsigned */
  62         if (errnum < sys_nerr)
  63                 return(sys_errlist[errnum]);
  64
  65         /* Do this by hand, so we don't include stdio(3). */
  66         t = tmp;
  67         do {
  68                 *t++ = "0123456789"[errnum % 10];
  69         } while (errnum /= 10);
  70         for (p = ebuf + sizeof(UPREFIX) - 1;;) {
  71                 *p++ = *--t;
  72                 if (t <= tmp)
  73                         break;
  74         }
  75         *p = '\0';
  76         return(ebuf);
  77 }