text: /*	$OpenBSD: herror.c,v 1.10 2015/09/14 07:38:38 guenther Exp $	*/
  
  /*
   * ++Copyright++ 1987, 1993
   * -
   * Copyright (c) 1987, 1993
   *    The Regents of the University of California.  All rights reserved.
   * 
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions
   * are met:
   * 1. Redistributions of source code must retain the above copyright
   *    notice, this list of conditions and the following disclaimer.
   * 2. Redistributions in binary form must reproduce the above copyright
   *    notice, this list of conditions and the following disclaimer in the
   *    documentation and/or other materials provided with the distribution.
   * 3. Neither the name of the University nor the names of its contributors
   *    may be used to endorse or promote products derived from this software
   *    without specific prior written permission.
   * 
   * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
   * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
   * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
   * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
   * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
   * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
   * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
   * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
   * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
   * SUCH DAMAGE.
   * -
   * Portions Copyright (c) 1993 by Digital Equipment Corporation.
   * 
   * Permission to use, copy, modify, and 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, and that
   * the name of Digital Equipment Corporation not be used in advertising or
   * publicity pertaining to distribution of the document or software without
   * specific, written prior permission.
   * 
   * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL
   * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES
   * OF MERCHANTABILITY AND FITNESS.   IN NO EVENT SHALL DIGITAL EQUIPMENT
   * CORPORATION 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.
   * -
   * --Copyright--
   */
  
  #include <sys/types.h>
  #include <sys/uio.h>
  #include <netdb.h>
  #include <unistd.h>
  #include <string.h>
  
  const char * const h_errlist[] = {
  	"Resolver Error 0 (no error)",
  	"Unknown host",				/* 1 HOST_NOT_FOUND */
  	"Host name lookup failure",		/* 2 TRY_AGAIN */
  	"Unknown server error",			/* 3 NO_RECOVERY */
  	"No address associated with name",	/* 4 NO_ADDRESS */
  };
  const int	h_nerr = { sizeof h_errlist / sizeof h_errlist[0] };
  
  extern int	h_errno;
  
  /*
   * herror --
   *	print the error indicated by the h_errno value.
   */
  void
  herror(const char *s)
  {
  	struct iovec iov[4];
  	struct iovec *v = iov;
  
  	if (s && *s) {
  		v->iov_base = (char *)s;
  		v->iov_len = strlen(s);
  		v++;
  		v->iov_base = ": ";
  		v->iov_len = 2;
  		v++;
  	}
  	v->iov_base = (char *)hstrerror(h_errno);
  	v->iov_len = strlen(v->iov_base);
  	v++;
  	v->iov_base = "\n";
  	v->iov_len = 1;
  	writev(STDERR_FILENO, iov, (v - iov) + 1);
  }
  
  const char *
  hstrerror(int err)
  {
  	if (err < 0)
  		return ("Resolver internal error");
  	else if (err < h_nerr)
  		return (h_errlist[err]);
  	return ("Unknown resolver error");
  }
  DEF_WEAK(hstrerror);
  