lib/libc/asr/res_send.c

   1 /*      $OpenBSD: res_send.c,v 1.4 2013/05/27 17:31:01 eric Exp $       */
   2 /*
   3  * Copyright (c) 2012 Eric Faurot <eric@openbsd.org>
   4  *
   5  * Permission to use, copy, modify, and distribute this software for any
   6  * purpose with or without fee is hereby granted, provided that the above
   7  * copyright notice and this permission notice appear in all copies.
   8  *
   9  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
  10  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  11  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
  12  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  13  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  14  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  15  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  16  */
  17
  18 #include <sys/types.h>
  19 #include <netinet/in.h>
  20
  21 #include <errno.h>
  22 #include <resolv.h>
  23 #include <string.h>
  24
  25 #include "asr.h"
  26
  27 int
  28 res_send(const u_char *buf, int buflen, u_char *ans, int anslen)
  29 {
  30         struct async    *as;
  31         struct async_res ar;
  32         size_t           len;
  33
  34         res_init();
  35
  36         if (ans == NULL || anslen <= 0) {
  37                 errno = EINVAL;
  38                 return (-1);
  39         }
  40
  41         as = res_send_async(buf, buflen, NULL);
  42         if (as == NULL)
  43                 return (-1); /* errno set */
  44
  45         async_run_sync(as, &ar);
  46
  47         if (ar.ar_errno) {
  48                 errno = ar.ar_errno;
  49                 return (-1);
  50         }
  51
  52         len = anslen;
  53         if (ar.ar_datalen < len)
  54                 len = ar.ar_datalen;
  55         memmove(ans, ar.ar_data, len);
  56         free(ar.ar_data);
  57
  58         return (ar.ar_datalen);
  59 }