crypto/heimdal-0.6.3/lib/roken/readv.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 #ifdef HAVE_CONFIG_H
  35 #include <config.h>
  36 RCSID("$Id: readv.c,v 1.5 1999/12/02 16:58:52 joda Exp $");
  37 #endif
  38
  39 #include "roken.h"
  40
  41 ssize_t
  42 readv(int d, const struct iovec *iov, int iovcnt)
  43 {
  44     ssize_t ret, nb;
  45     size_t tot = 0;
  46     int i;
  47     char *buf, *p;
  48
  49     for(i = 0; i < iovcnt; ++i)
  50         tot += iov[i].iov_len;
  51     buf = malloc(tot);
  52     if (tot != 0 && buf == NULL) {
  53         errno = ENOMEM;
  54         return -1;
  55     }
  56     nb = ret = read (d, buf, tot);
  57     p = buf;
  58     while (nb > 0) {
  59         ssize_t cnt = min(nb, iov->iov_len);
  60
  61         memcpy (iov->iov_base, p, cnt);
  62         p += cnt;
  63         nb -= cnt;
  64     }
  65     free(buf);
  66     return ret;
  67 }