Annotation of src/usr.bin/telnet/network.c, Revision 1.3
1.3 ! robin 1: /* $OpenBSD: network.c,v 1.2 1996/03/27 19:33:04 niklas Exp $ */
1.2 niklas 2: /* $NetBSD: network.c,v 1.5 1996/02/28 21:04:06 thorpej Exp $ */
3:
1.1 deraadt 4: /*
5: * Copyright (c) 1988, 1993
6: * The Regents of the University of California. 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: * 1. Redistributions of source code must retain the above copyright
12: * notice, this list of conditions and the following disclaimer.
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: * 3. All advertising materials mentioning features or use of this software
17: * must display the following acknowledgement:
18: * This product includes software developed by the University of
19: * California, Berkeley and its contributors.
20: * 4. Neither the name of the University nor the names of its contributors
21: * may be used to endorse or promote products derived from this software
22: * without specific prior written permission.
23: *
24: * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25: * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26: * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27: * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28: * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29: * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30: * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31: * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32: * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33: * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34: * SUCH DAMAGE.
35: */
36:
37: #ifndef lint
1.2 niklas 38: #if 0
39: static char sccsid[] = "@(#)network.c 8.2 (Berkeley) 12/15/93";
40: static char rcsid[] = "$NetBSD: network.c,v 1.5 1996/02/28 21:04:06 thorpej Exp $";
41: #else
1.3 ! robin 42: static char rcsid[] = "$OpenBSD: network.c,v 1.2 1996/03/27 19:33:04 niklas Exp $";
1.2 niklas 43: #endif
1.1 deraadt 44: #endif /* not lint */
45:
46: #include <sys/types.h>
47: #include <sys/socket.h>
48: #include <sys/time.h>
1.3 ! robin 49: #include <unistd.h>
1.1 deraadt 50: #include <errno.h>
51:
52: #include <arpa/telnet.h>
53:
54: #include "ring.h"
55:
56: #include "defines.h"
57: #include "externs.h"
58: #include "fdset.h"
59:
60: Ring netoring, netiring;
61: unsigned char netobuf[2*BUFSIZ], netibuf[BUFSIZ];
62:
63: /*
64: * Initialize internal network data structures.
65: */
66:
67: void
68: init_network()
69: {
70: if (ring_init(&netoring, netobuf, sizeof netobuf) != 1) {
71: exit(1);
72: }
73: if (ring_init(&netiring, netibuf, sizeof netibuf) != 1) {
74: exit(1);
75: }
76: NetTrace = stdout;
77: }
78:
79:
80: /*
81: * Check to see if any out-of-band data exists on a socket (for
82: * Telnet "synch" processing).
83: */
84:
85: int
86: stilloob()
87: {
88: static struct timeval timeout = { 0 };
89: fd_set excepts;
90: int value;
91:
92: do {
93: FD_ZERO(&excepts);
94: FD_SET(net, &excepts);
95: value = select(net+1, (fd_set *)0, (fd_set *)0, &excepts, &timeout);
96: } while ((value == -1) && (errno == EINTR));
97:
98: if (value < 0) {
99: perror("select");
100: (void) quit();
101: /* NOTREACHED */
102: }
103: if (FD_ISSET(net, &excepts)) {
104: return 1;
105: } else {
106: return 0;
107: }
108: }
109:
110:
111: /*
112: * setneturg()
113: *
114: * Sets "neturg" to the current location.
115: */
116:
117: void
118: setneturg()
119: {
120: ring_mark(&netoring);
121: }
122:
123:
124: /*
125: * netflush
126: * Send as much data as possible to the network,
127: * handling requests for urgent data.
128: *
129: * The return value indicates whether we did any
130: * useful work.
131: */
132:
133:
134: int
135: netflush()
136: {
137: register int n, n1;
138:
139: if ((n1 = n = ring_full_consecutive(&netoring)) > 0) {
140: if (!ring_at_mark(&netoring)) {
141: n = send(net, (char *)netoring.consume, n, 0); /* normal write */
142: } else {
143: /*
144: * In 4.2 (and 4.3) systems, there is some question about
145: * what byte in a sendOOB operation is the "OOB" data.
146: * To make ourselves compatible, we only send ONE byte
147: * out of band, the one WE THINK should be OOB (though
148: * we really have more the TCP philosophy of urgent data
149: * rather than the Unix philosophy of OOB data).
150: */
151: n = send(net, (char *)netoring.consume, 1, MSG_OOB);/* URGENT data */
152: }
153: }
154: if (n < 0) {
155: if (errno != ENOBUFS && errno != EWOULDBLOCK) {
156: setcommandmode();
157: perror(hostname);
158: (void)NetClose(net);
159: ring_clear_mark(&netoring);
160: longjmp(peerdied, -1);
161: /*NOTREACHED*/
162: }
163: n = 0;
164: }
165: if (netdata && n) {
166: Dump('>', netoring.consume, n);
167: }
168: if (n) {
169: ring_consumed(&netoring, n);
170: /*
171: * If we sent all, and more to send, then recurse to pick
172: * up the other half.
173: */
174: if ((n1 == n) && ring_full_consecutive(&netoring)) {
175: (void) netflush();
176: }
177: return 1;
178: } else {
179: return 0;
180: }
181: }