1 /*	$NetBSD: net_read.c,v 1.1.1.1 2011/04/13 18:15:42 elric Exp $	*/
2 
3 /*
4  * Copyright (c) 1995, 1996, 1997, 1998 Kungliga Tekniska Högskolan
5  * (Royal Institute of Technology, Stockholm, Sweden).
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  *
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  *
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * 3. Neither the name of the Institute nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  */
35 
36 #include <config.h>
37 
38 #include <krb5/roken.h>
39 
40 /*
41  * Like read but never return partial data.
42  */
43 
44 #ifndef _WIN32
45 
46 ROKEN_LIB_FUNCTION ssize_t ROKEN_LIB_CALL
net_read(rk_socket_t fd,void * buf,size_t nbytes)47 net_read (rk_socket_t fd, void *buf, size_t nbytes)
48 {
49     char *cbuf = (char *)buf;
50     ssize_t count;
51     size_t rem = nbytes;
52 
53     while (rem > 0) {
54 	count = read (fd, cbuf, rem);
55 	if (count < 0) {
56 	    if (errno == EINTR)
57 		continue;
58 	    else
59 		return count;
60 	} else if (count == 0) {
61 	    return count;
62 	}
63 	cbuf += count;
64 	rem -= count;
65     }
66     return nbytes;
67 }
68 
69 #else
70 
71 ROKEN_LIB_FUNCTION ssize_t ROKEN_LIB_CALL
net_read(rk_socket_t sock,void * buf,size_t nbytes)72 net_read(rk_socket_t sock, void *buf, size_t nbytes)
73 {
74     char *cbuf = (char *)buf;
75     ssize_t count;
76     size_t rem = nbytes;
77 
78 #ifdef SOCKET_IS_NOT_AN_FD
79     int use_read = 0;
80 #endif
81 
82     while (rem > 0) {
83 #ifdef SOCKET_IS_NOT_AN_FD
84 	if (use_read)
85 	    count = _read (sock, cbuf, rem);
86 	else
87 	    count = recv (sock, cbuf, rem, 0);
88 
89 	if (use_read == 0 &&
90 	    rk_IS_SOCKET_ERROR(count) &&
91             (rk_SOCK_ERRNO == WSANOTINITIALISED ||
92              rk_SOCK_ERRNO == WSAENOTSOCK)) {
93 	    use_read = 1;
94 
95 	    count = _read (sock, cbuf, rem);
96 	}
97 #else
98 	count = recv (sock, cbuf, rem, 0);
99 #endif
100 	if (count < 0) {
101 
102 	    /* With WinSock, the error EINTR (WSAEINTR), is used to
103 	       indicate that a blocking call was cancelled using
104 	       WSACancelBlockingCall(). */
105 
106 #ifndef HAVE_WINSOCK
107 	    if (rk_SOCK_ERRNO == EINTR)
108 		continue;
109 #endif
110 	    return count;
111 	} else if (count == 0) {
112 	    return count;
113 	}
114 	cbuf += count;
115 	rem -= count;
116     }
117     return nbytes;
118 }
119 
120 #endif
121