xref: /openbsd-src/usr.bin/mail/tty.c (revision b2ea75c1b17e1a9a339660e7ed45cd24946b230e)
1 /*	$OpenBSD: tty.c,v 1.12 2001/06/23 23:04:23 millert Exp $	*/
2 /*	$NetBSD: tty.c,v 1.7 1997/07/09 05:25:46 mikel Exp $	*/
3 
4 /*
5  * Copyright (c) 1980, 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
38 #if 0
39 static char sccsid[] = "@(#)tty.c	8.2 (Berkeley) 4/20/95";
40 #else
41 static char rcsid[] = "$OpenBSD: tty.c,v 1.12 2001/06/23 23:04:23 millert Exp $";
42 #endif
43 #endif /* not lint */
44 
45 /*
46  * Mail -- a mail program
47  *
48  * Generally useful tty stuff.
49  */
50 
51 #include "rcv.h"
52 #include "extern.h"
53 #include <sys/ioctl.h>
54 
55 static	cc_t		c_erase;	/* Current erase char */
56 static	cc_t		c_kill;		/* Current kill char */
57 static	sigjmp_buf	rewrite;	/* Place to go when continued */
58 static	sigjmp_buf	intjmp;		/* Place to go when interrupted */
59 #ifndef TIOCSTI
60 static	int		ttyset;		/* We must now do erase/kill */
61 #endif
62 
63 /*
64  * Read all relevant header fields.
65  */
66 
67 int
68 grabh(hp, gflags)
69 	struct header *hp;
70 	int gflags;
71 {
72 	struct termios ttybuf;
73 	volatile sig_t saveint;
74 #ifndef TIOCSTI
75 	sig_t savequit;
76 #else
77 # ifdef	TIOCEXT
78 	volatile int extproc;
79 	int flag;
80 # endif /* TIOCEXT */
81 #endif
82 	sig_t savetstp;
83 	sig_t savettou;
84 	sig_t savettin;
85 	volatile int errs = 0;
86 
87 	savetstp = signal(SIGTSTP, SIG_DFL);
88 	savettou = signal(SIGTTOU, SIG_DFL);
89 	savettin = signal(SIGTTIN, SIG_DFL);
90 	errs = 0;
91 #ifndef TIOCSTI
92 	ttyset = 0;
93 #endif
94 	if (tcgetattr(fileno(stdin), &ttybuf) < 0) {
95 		warn("tcgetattr");
96 		return(-1);
97 	}
98 	c_erase = ttybuf.c_cc[VERASE];
99 	c_kill = ttybuf.c_cc[VKILL];
100 #ifndef TIOCSTI
101 	ttybuf.c_cc[VERASE] = 0;
102 	ttybuf.c_cc[VKILL] = 0;
103 	if ((saveint = signal(SIGINT, SIG_IGN)) == SIG_DFL)
104 		(void)signal(SIGINT, SIG_DFL);
105 	if ((savequit = signal(SIGQUIT, SIG_IGN)) == SIG_DFL)
106 		(void)signal(SIGQUIT, SIG_DFL);
107 #else
108 # ifdef	TIOCEXT
109 	extproc = ((ttybuf.c_lflag & EXTPROC) ? 1 : 0);
110 	if (extproc) {
111 		flag = 0;
112 		if (ioctl(fileno(stdin), TIOCEXT, &flag) < 0)
113 			warn("TIOCEXT: off");
114 	}
115 # endif /* TIOCEXT */
116 	if (sigsetjmp(intjmp, 1)) {
117 		errs = SIGINT;
118 		goto out;
119 	}
120 	saveint = signal(SIGINT, ttyint);
121 #endif
122 	if (gflags & GTO) {
123 #ifndef TIOCSTI
124 		if (!ttyset && hp->h_to != NIL)
125 			ttyset++, tcsetattr(fileno(stdin), TCSADRAIN, &ttybuf);
126 #endif
127 		hp->h_to =
128 			extract(readtty("To: ", detract(hp->h_to, 0)), GTO);
129 	}
130 	if (gflags & GSUBJECT) {
131 #ifndef TIOCSTI
132 		if (!ttyset && hp->h_subject != NULL)
133 			ttyset++, tcsetattr(fileno(stdin), TCSADRAIN, &ttybuf);
134 #endif
135 		hp->h_subject = readtty("Subject: ", hp->h_subject);
136 	}
137 	if (gflags & GCC) {
138 #ifndef TIOCSTI
139 		if (!ttyset && hp->h_cc != NIL)
140 			ttyset++, tcsetattr(fileno(stdin), TCSADRAIN, &ttybuf);
141 #endif
142 		hp->h_cc =
143 			extract(readtty("Cc: ", detract(hp->h_cc, 0)), GCC);
144 	}
145 	if (gflags & GBCC) {
146 #ifndef TIOCSTI
147 		if (!ttyset && hp->h_bcc != NIL)
148 			ttyset++, tcsetattr(fileno(stdin), TCSADRAIN, &ttybuf);
149 #endif
150 		hp->h_bcc =
151 			extract(readtty("Bcc: ", detract(hp->h_bcc, 0)), GBCC);
152 	}
153 out:
154 	(void)signal(SIGTSTP, savetstp);
155 	(void)signal(SIGTTOU, savettou);
156 	(void)signal(SIGTTIN, savettin);
157 #ifndef TIOCSTI
158 	ttybuf.c_cc[VERASE] = c_erase;
159 	ttybuf.c_cc[VKILL] = c_kill;
160 	if (ttyset)
161 		tcsetattr(fileno(stdin), TCSADRAIN, &ttybuf);
162 	(void)signal(SIGQUIT, savequit);
163 #else
164 # ifdef	TIOCEXT
165 	if (extproc) {
166 		flag = 1;
167 		if (ioctl(fileno(stdin), TIOCEXT, &flag) < 0)
168 			warn("TIOCEXT: on");
169 	}
170 # endif /* TIOCEXT */
171 #endif
172 	(void)signal(SIGINT, saveint);
173 	return(errs);
174 }
175 
176 /*
177  * Read up a header from standard input.
178  * The source string has the preliminary contents to
179  * be read.
180  *
181  */
182 
183 char *
184 readtty(pr, src)
185 	char pr[], src[];
186 {
187 	char ch, canonb[BUFSIZ];
188 	volatile int c;
189 	char *cp, * volatile cp2;
190 
191 	fputs(pr, stdout);
192 	fflush(stdout);
193 	if (src != NULL && strlen(src) > BUFSIZ - 2) {
194 		puts("too long to edit");
195 		return(src);
196 	}
197 #ifndef TIOCSTI
198 	if (src != NULL)
199 		cp = copy(src, canonb);
200 	else
201 		cp = copy("", canonb);
202 	fputs(canonb, stdout);
203 	fflush(stdout);
204 #else
205 	cp = src == NULL ? "" : src;
206 	while ((c = *cp++) != '\0') {
207 		if ((c_erase != _POSIX_VDISABLE && c == c_erase) ||
208 		    (c_kill != _POSIX_VDISABLE && c == c_kill)) {
209 			ch = '\\';
210 			ioctl(0, TIOCSTI, &ch);
211 		}
212 		ch = c;
213 		ioctl(0, TIOCSTI, &ch);
214 	}
215 	cp = canonb;
216 	*cp = 0;
217 #endif
218 	cp2 = cp;
219 	while (cp2 < canonb + BUFSIZ)
220 		*cp2++ = 0;
221 	cp2 = cp;
222 	if (sigsetjmp(rewrite, 1))
223 		goto redo;
224 	(void)signal(SIGTSTP, ttystop);
225 	(void)signal(SIGTTOU, ttystop);
226 	(void)signal(SIGTTIN, ttystop);
227 	clearerr(stdin);
228 	while (cp2 < canonb + BUFSIZ) {
229 		c = getc(stdin);
230 		if (c == EOF || c == '\n')
231 			break;
232 		*cp2++ = c;
233 	}
234 	*cp2 = 0;
235 	(void)signal(SIGTSTP, SIG_DFL);
236 	(void)signal(SIGTTOU, SIG_DFL);
237 	(void)signal(SIGTTIN, SIG_DFL);
238 	if (c == EOF && ferror(stdin)) {
239 redo:
240 		cp = strlen(canonb) > 0 ? canonb : NULL;
241 		clearerr(stdin);
242 		return(readtty(pr, cp));
243 	}
244 #ifndef TIOCSTI
245 	if (cp == NULL || *cp == '\0')
246 		return(src);
247 	cp2 = cp;
248 	if (!ttyset)
249 		return(strlen(canonb) > 0 ? savestr(canonb) : NULL);
250 	while (*cp != '\0') {
251 		c = *cp++;
252 		if (c_erase != _POSIX_VDISABLE && c == c_erase) {
253 			if (cp2 == canonb)
254 				continue;
255 			if (cp2[-1] == '\\') {
256 				cp2[-1] = c;
257 				continue;
258 			}
259 			cp2--;
260 			continue;
261 		}
262 		if (c_kill != _POSIX_VDISABLE && c == c_kill) {
263 			if (cp2 == canonb)
264 				continue;
265 			if (cp2[-1] == '\\') {
266 				cp2[-1] = c;
267 				continue;
268 			}
269 			cp2 = canonb;
270 			continue;
271 		}
272 		*cp2++ = c;
273 	}
274 	*cp2 = '\0';
275 #endif
276 	if (equal("", canonb))
277 		return(NULL);
278 	return(savestr(canonb));
279 }
280 
281 /*
282  * Receipt continuation.
283  */
284 void
285 ttystop(s)
286 	int s;
287 {
288 	sig_t old_action = signal(s, SIG_DFL);
289 	sigset_t nset;
290 
291 	(void)sigemptyset(&nset);
292 	(void)sigaddset(&nset, s);
293 	(void)sigprocmask(SIG_UNBLOCK, &nset, NULL);
294 	(void)kill(0, s);
295 	(void)sigprocmask(SIG_BLOCK, &nset, NULL);
296 	(void)signal(s, old_action);
297 	siglongjmp(rewrite, 1);
298 }
299 
300 /*ARGSUSED*/
301 void
302 ttyint(s)
303 	int s;
304 {
305 	siglongjmp(intjmp, 1);
306 }
307