recvmsg.c revision 55682 
1/*
2 * Copyright (c) 1995, 1996, 1997, 1998, 1999 Kungliga Tekniska H�gskolan
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#ifdef HAVE_CONFIG_H
35#include <config.h>
36RCSID("$Id: recvmsg.c,v 1.5 1999/12/02 16:58:52 joda Exp $");
37#endif
38
39#include "roken.h"
40
41ssize_t
42recvmsg(int s, struct msghdr *msg, int flags)
43{
44    ssize_t ret, nb;
45    size_t tot = 0;
46    int i;
47    char *buf, *p;
48    struct iovec *iov = msg->msg_iov;
49
50    for(i = 0; i < msg->msg_iovlen; ++i)
51	tot += iov[i].iov_len;
52    buf = malloc(tot);
53    if (tot != 0 && buf == NULL) {
54	errno = ENOMEM;
55	return -1;
56    }
57    nb = ret = recvfrom (s, buf, tot, flags, msg->msg_name, &msg->msg_namelen);
58    p = buf;
59    while (nb > 0) {
60	ssize_t cnt = min(nb, iov->iov_len);
61
62	memcpy (iov->iov_base, p, cnt);
63	p += cnt;
64	nb -= cnt;
65	++iov;
66    }
67    free(buf);
68    return ret;
69}
70