contrib/ntp/libisc/strerror.c

   1 /*
   2  * Copyright (C) 2001  Internet Software Consortium.
   3  *
   4  * Permission to use, copy, modify, and distribute this software for any
   5  * purpose with or without fee is hereby granted, provided that the above
   6  * copyright notice and this permission notice appear in all copies.
   7  *
   8  * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM
   9  * DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL
  10  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL
  11  * INTERNET SOFTWARE CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT,
  12  * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING
  13  * FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT,
  14  * NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION
  15  * WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  16  */
  17
  18 /* $Id: strerror.c,v 1.3 2001/11/20 01:45:45 gson Exp $ */
  19
  20 #include <config.h>
  21
  22 #include <stdio.h>
  23 #include <string.h>
  24
  25 #include <isc/mutex.h>
  26 #include <isc/once.h>
  27 #include <isc/print.h>
  28 #include <isc/strerror.h>
  29 #include <isc/util.h>
  30
  31 #ifdef HAVE_STRERROR
  32 /*
  33  * We need to do this this way for profiled locks.
  34  */
  35 static isc_mutex_t isc_strerror_lock;
  36 static void init_lock(void) {
  37         RUNTIME_CHECK(isc_mutex_init(&isc_strerror_lock) == ISC_R_SUCCESS);
  38 }
  39 #else
  40 extern const char * const sys_errlist[];
  41 extern const int sys_nerr;
  42 #endif
  43
  44 void
  45 isc__strerror(int num, char *buf, size_t size) {
  46 #ifdef HAVE_STRERROR
  47         char *msg;
  48         unsigned int unum = num;
  49         static isc_once_t once = ISC_ONCE_INIT;
  50
  51         REQUIRE(buf != NULL);
  52
  53         RUNTIME_CHECK(isc_once_do(&once, init_lock) == ISC_R_SUCCESS);
  54
  55         LOCK(&isc_strerror_lock);
  56         msg = strerror(num);
  57         if (msg != NULL)
  58                 snprintf(buf, size, "%s", msg);
  59         else
  60                 snprintf(buf, size, "Unknown error: %u", unum);
  61         UNLOCK(&isc_strerror_lock);
  62 #else
  63         unsigned int unum = num;
  64
  65         REQUIRE(buf != NULL);
  66
  67         if (num >= 0 && num < sys_nerr)
  68                 snprintf(buf, size, "%s", sys_errlist[num]);
  69         else
  70                 snprintf(buf, size, "Unknown error: %u", unum);
  71 #endif
  72 }