xref: /freebsd/crypto/heimdal/lib/roken/net_read.c (revision 2be1a816b9ff69588e55be0a84cbe2a31efc0f2f)
1 /*
2  * Copyright (c) 1995, 1996, 1997, 1998 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>
36 RCSID("$Id: net_read.c,v 1.3 1999/12/02 16:58:51 joda Exp $");
37 #endif
38 
39 #include <sys/types.h>
40 #include <unistd.h>
41 #include <errno.h>
42 
43 #include <roken.h>
44 
45 /*
46  * Like read but never return partial data.
47  */
48 
49 ssize_t
50 net_read (int fd, void *buf, size_t nbytes)
51 {
52     char *cbuf = (char *)buf;
53     ssize_t count;
54     size_t rem = nbytes;
55 
56     while (rem > 0) {
57 #ifdef WIN32
58 	count = recv (fd, cbuf, rem, 0);
59 #else
60 	count = read (fd, cbuf, rem);
61 #endif
62 	if (count < 0) {
63 	    if (errno == EINTR)
64 		continue;
65 	    else
66 		return count;
67 	} else if (count == 0) {
68 	    return count;
69 	}
70 	cbuf += count;
71 	rem -= count;
72     }
73     return nbytes;
74 }
75