lib/roken/recvmsg.c

   1 /*
   2  * Copyright (c) 1995, 1996, 1997, 1998, 1999 Kungliga Tekniska Högskolan
   3  * (Royal Institute of Technology, Stockholm, Sweden).
   4  * All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions
   8  * are met:
   9  *
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  *
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in the
  15  *    documentation and/or other materials provided with the distribution.
  16  *
  17  * 3. Neither the name of the Institute nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  */
  33
  34 #include <config.h>
  35
  36 #include "roken.h"
  37
  38 ssize_t ROKEN_LIB_FUNCTION
  39 recvmsg(int s, struct msghdr *msg, int flags)
  40 {
  41     ssize_t ret, nb;
  42     size_t tot = 0;
  43     int i;
  44     char *buf, *p;
  45     struct iovec *iov = msg->msg_iov;
  46
  47     for(i = 0; i < msg->msg_iovlen; ++i)
  48         tot += iov[i].iov_len;
  49     buf = malloc(tot);
  50     if (tot != 0 && buf == NULL) {
  51         errno = ENOMEM;
  52         return -1;
  53     }
  54     nb = ret = recvfrom (s, buf, tot, flags, msg->msg_name, &msg->msg_namelen);
  55     p = buf;
  56     while (nb > 0) {
  57         ssize_t cnt = min(nb, iov->iov_len);
  58
  59         memcpy (iov->iov_base, p, cnt);
  60         p += cnt;
  61         nb -= cnt;
  62         ++iov;
  63     }
  64     free(buf);
  65     return ret;
  66 }