xref: /openbsd-src/usr.bin/telnet/terminal.c (revision f2da64fbbbf1b03f09f390ab01267c93dfd77c4c)
1 /*	$OpenBSD: terminal.c,v 1.13 2014/07/22 07:30:24 jsg Exp $	*/
2 /*	$NetBSD: terminal.c,v 1.5 1996/02/28 21:04:17 thorpej Exp $	*/
3 
4 /*
5  * Copyright (c) 1988, 1990, 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. Neither the name of the University nor the names of its contributors
17  *    may be used to endorse or promote products derived from this software
18  *    without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  */
32 
33 #include "telnet_locl.h"
34 
35 #include <arpa/telnet.h>
36 #include <errno.h>
37 #include <unistd.h>
38 
39 Ring		ttyoring, ttyiring;
40 unsigned char	ttyobuf[2*BUFSIZ], ttyibuf[BUFSIZ];
41 
42 int termdata;			/* Debugging flag */
43 
44 # ifndef VDISCARD
45 cc_t termFlushChar;
46 # endif
47 # ifndef VLNEXT
48 cc_t termLiteralNextChar;
49 # endif
50 # ifndef VWERASE
51 cc_t termWerasChar;
52 # endif
53 # ifndef VREPRINT
54 cc_t termRprntChar;
55 # endif
56 # ifndef VSTART
57 cc_t termStartChar;
58 # endif
59 # ifndef VSTOP
60 cc_t termStopChar;
61 # endif
62 # ifndef VEOL
63 cc_t termForw1Char;
64 # endif
65 # ifndef VEOL2
66 cc_t termForw2Char;
67 # endif
68 # ifndef VSTATUS
69 cc_t termAytChar;
70 # endif
71 
72 /*
73  * initialize the terminal data structures.
74  */
75 
76 void
77 init_terminal(void)
78 {
79 	struct termios tc;
80 
81 	ring_init(&ttyoring, ttyobuf, sizeof ttyobuf);
82 	ring_init(&ttyiring, ttyibuf, sizeof ttyibuf);
83 
84 	tcgetattr(0, &tc);
85 	autoflush = (tc.c_lflag & NOFLSH) == 0;
86 }
87 
88 /*
89  *		Send as much data as possible to the terminal.
90  *
91  *		Return value:
92  *			-1: No useful work done, data waiting to go out.
93  *			 0: No data was waiting, so nothing was done.
94  *			 1: All waiting data was written out.
95  *			 n: All data - n was written out.
96  */
97 
98 int
99 ttyflush(int drop)
100 {
101     int n, n0, n1;
102 
103     n0 = ring_full_count(&ttyoring);
104     if ((n1 = n = ring_full_consecutive(&ttyoring)) > 0) {
105 	if (drop) {
106 	    tcflush(fileno(stdout), TCOFLUSH);
107 	    /* we leave 'n' alone! */
108 	} else {
109 	    n = write(tout, ttyoring.consume, n);
110 	}
111     }
112     if (n > 0) {
113 	if (termdata && n) {
114 	    Dump('>', ttyoring.consume, n);
115 	}
116 	/*
117 	 * If we wrote everything, and the full count is
118 	 * larger than what we wrote, then write the
119 	 * rest of the buffer.
120 	 */
121 	if (n1 == n && n0 > n) {
122 		n1 = n0 - n;
123 		if (!drop)
124 			n1 = write(tout, ttyoring.bottom, n1);
125 		if (n1 > 0)
126 			n += n1;
127 	}
128 	ring_consumed(&ttyoring, n);
129     }
130     if (n < 0) {
131 	if (errno == EPIPE)
132 		kill(0, SIGQUIT);
133 	return -1;
134     }
135     if (n == n0) {
136 	if (n0)
137 	    return -1;
138 	return 0;
139     }
140     return n0 - n + 1;
141 }
142 
143 
144 /*
145  * These routines decides on what the mode should be (based on the values
146  * of various global variables).
147  */
148 
149 int
150 getconnmode(void)
151 {
152     int mode = 0;
153 
154     if (my_want_state_is_dont(TELOPT_ECHO))
155 	mode |= MODE_ECHO;
156 
157     if (localflow)
158 	mode |= MODE_FLOW;
159 
160     if ((eight & 1) || my_want_state_is_will(TELOPT_BINARY))
161 	mode |= MODE_INBIN;
162 
163     if (eight & 2)
164 	mode |= MODE_OUT8;
165     if (his_want_state_is_will(TELOPT_BINARY))
166 	mode |= MODE_OUTBIN;
167 
168 #ifdef	KLUDGELINEMODE
169     if (kludgelinemode) {
170 	if (my_want_state_is_dont(TELOPT_SGA)) {
171 	    mode |= (MODE_TRAPSIG|MODE_EDIT);
172 	    if (dontlecho && (clocks.echotoggle > clocks.modenegotiated)) {
173 		mode &= ~MODE_ECHO;
174 	    }
175 	}
176 	return(mode);
177     }
178 #endif
179     if (my_want_state_is_will(TELOPT_LINEMODE))
180 	mode |= linemode;
181     return(mode);
182 }
183 
184 void
185 setconnmode(int force)
186 {
187     int newmode;
188 
189     newmode = getconnmode()|(force?MODE_FORCE:0);
190 
191     TerminalNewMode(newmode);
192 }
193 
194 void
195 setcommandmode(void)
196 {
197     TerminalNewMode(-1);
198 }
199