/*

 * Copyright (C) 2004, 2005, 2007, 2009  Internet Systems Consortium, Inc. ("ISC")

 * Copyright (C) 2001  Internet Software Consortium.

 *

 * Permission to use, copy, modify, and/or distribute this software for any

 * purpose with or without fee is hereby granted, provided that the above

 * copyright notice and this permission notice appear in all copies.

 *

 * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH

 * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY

 * AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,

 * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM

 * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE

 * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR

 * PERFORMANCE OF THIS SOFTWARE.

 */

/* $Id: strerror.c,v 1.10 2009/02/16 23:48:04 tbox Exp $ */

/*! \file */

#include <config.h>

#include <stdio.h>

#include <string.h>

#include <isc/mutex.h>

#include <isc/once.h>

#include <isc/print.h>

#include <isc/strerror.h>

#include <isc/util.h>

#include "l_stdlib.h"   /* NTP local change */

#ifdef HAVE_STRERROR

/*%

 * We need to do this this way for profiled locks.

 */

static isc_mutex_t isc_strerror_lock;

static void init_lock(void) {

  RUNTIME_CHECK(isc_mutex_init(&isc_strerror_lock) == ISC_R_SUCCESS);

}

#else

extern const char * const sys_errlist[];

extern const int sys_nerr;

#endif

void

isc__strerror(int num, char *buf, size_t size) {

#ifdef HAVE_STRERROR

  char *msg;

  unsigned int unum = (unsigned int)num;

  static isc_once_t once = ISC_ONCE_INIT;

  REQUIRE(buf != NULL);

  RUNTIME_CHECK(isc_once_do(&once, init_lock) == ISC_R_SUCCESS);

  LOCK(&isc_strerror_lock);

  msg = strerror(num);

  if (msg != NULL)

    snprintf(buf, size, "%s", msg);

  else

    snprintf(buf, size, "Unknown error: %u", unum);

  UNLOCK(&isc_strerror_lock);

#else

  unsigned int unum = (unsigned int)num;

  REQUIRE(buf != NULL);

  if (num >= 0 && num < sys_nerr)

    snprintf(buf, size, "%s", sys_errlist[num]);

  else

    snprintf(buf, size, "Unknown error: %u", unum);

#endif

}