xref: /freebsd/crypto/heimdal/lib/roken/net_read.c (revision d4eeb02986980bf33dd56c41ceb9fc5f180c0d47)
1 /*
2  * Copyright (c) 1995, 1996, 1997, 1998 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 /*
39  * Like read but never return partial data.
40  */
41 
42 #ifndef _WIN32
43 
44 ROKEN_LIB_FUNCTION ssize_t ROKEN_LIB_CALL
45 net_read (rk_socket_t fd, void *buf, size_t nbytes)
46 {
47     char *cbuf = (char *)buf;
48     ssize_t count;
49     size_t rem = nbytes;
50 
51     while (rem > 0) {
52 	count = read (fd, cbuf, rem);
53 	if (count < 0) {
54 	    if (errno == EINTR)
55 		continue;
56 	    else
57 		return count;
58 	} else if (count == 0) {
59 	    return count;
60 	}
61 	cbuf += count;
62 	rem -= count;
63     }
64     return nbytes;
65 }
66 
67 #else
68 
69 ROKEN_LIB_FUNCTION ssize_t ROKEN_LIB_CALL
70 net_read(rk_socket_t sock, void *buf, size_t nbytes)
71 {
72     char *cbuf = (char *)buf;
73     ssize_t count;
74     size_t rem = nbytes;
75 
76 #ifdef SOCKET_IS_NOT_AN_FD
77     int use_read = 0;
78 #endif
79 
80     while (rem > 0) {
81 #ifdef SOCKET_IS_NOT_AN_FD
82 	if (use_read)
83 	    count = _read (sock, cbuf, rem);
84 	else
85 	    count = recv (sock, cbuf, rem, 0);
86 
87 	if (use_read == 0 &&
88 	    rk_IS_SOCKET_ERROR(count) &&
89             (rk_SOCK_ERRNO == WSANOTINITIALISED ||
90              rk_SOCK_ERRNO == WSAENOTSOCK)) {
91 	    use_read = 1;
92 
93 	    count = _read (sock, cbuf, rem);
94 	}
95 #else
96 	count = recv (sock, cbuf, rem, 0);
97 #endif
98 	if (count < 0) {
99 
100 	    /* With WinSock, the error EINTR (WSAEINTR), is used to
101 	       indicate that a blocking call was cancelled using
102 	       WSACancelBlockingCall(). */
103 
104 #ifndef HAVE_WINSOCK
105 	    if (rk_SOCK_ERRNO == EINTR)
106 		continue;
107 #endif
108 	    return count;
109 	} else if (count == 0) {
110 	    return count;
111 	}
112 	cbuf += count;
113 	rem -= count;
114     }
115     return nbytes;
116 }
117 
118 #endif
119