xref: /netbsd-src/usr.bin/mail/tty.c (revision 23c8222edbfb0f0932d88a8351d3a0cf817dfb9e)
1 /*	$NetBSD: tty.c,v 1.17 2003/08/07 11:14:42 agc Exp $	*/
2 
3 /*
4  * Copyright (c) 1980, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 #include <sys/cdefs.h>
33 #ifndef lint
34 #if 0
35 static char sccsid[] = "@(#)tty.c	8.2 (Berkeley) 6/6/93";
36 #else
37 __RCSID("$NetBSD: tty.c,v 1.17 2003/08/07 11:14:42 agc Exp $");
38 #endif
39 #endif /* not lint */
40 
41 /*
42  * Mail -- a mail program
43  *
44  * Generally useful tty stuff.
45  */
46 
47 #include "rcv.h"
48 #include "extern.h"
49 
50 static	cc_t	c_erase;		/* Current erase char */
51 static	cc_t	c_kill;			/* Current kill char */
52 static	jmp_buf	rewrite;		/* Place to go when continued */
53 static	jmp_buf	intjmp;			/* Place to go when interrupted */
54 #ifndef TIOCSTI
55 static	int	ttyset;			/* We must now do erase/kill */
56 #endif
57 
58 /*
59  * Read all relevant header fields.
60  */
61 
62 int
63 grabh(struct header *hp, int gflags)
64 {
65 	struct termios ttybuf;
66 	sig_t saveint;
67 	sig_t savetstp;
68 	sig_t savettou;
69 	sig_t savettin;
70 	int errs;
71 #ifndef TIOCSTI
72 	sig_t savequit;
73 #else
74 # ifdef TIOCEXT
75 	int extproc, flag;
76 # endif /* TIOCEXT */
77 #endif /* TIOCSTI */
78 
79 #ifdef __GNUC__
80 	/* Avoid longjmp clobbering */
81 # if defined(TIOCSTI) && defined(TIOCEXT)
82 	(void)&extproc;
83 # endif
84 	(void)&saveint;
85 #endif /* __GNUC__ */
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] = _POSIX_VDISABLE;
102 	ttybuf.c_cc[VKILL] = _POSIX_VDISABLE;
103 	if ((saveint = signal(SIGINT, SIG_IGN)) == SIG_DFL)
104 		signal(SIGINT, SIG_DFL);
105 	if ((savequit = signal(SIGQUIT, SIG_IGN)) == SIG_DFL)
106 		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 (setjmp(intjmp))
117 		goto out;
118 	saveint = signal(SIGINT, ttyint);
119 #endif
120 	if (gflags & GTO) {
121 #ifndef TIOCSTI
122 		if (!ttyset && hp->h_to != NULL)
123 			ttyset++, tcsetattr(fileno(stdin), TCSADRAIN, &ttybuf);
124 #endif
125 		hp->h_to =
126 			extract(readtty("To: ", detract(hp->h_to, 0)), GTO);
127 	}
128 	if (gflags & GSUBJECT) {
129 #ifndef TIOCSTI
130 		if (!ttyset && hp->h_subject != NULL)
131 			ttyset++, tcsetattr(fileno(stdin), TCSADRAIN, &ttybuf);
132 #endif
133 		hp->h_subject = readtty("Subject: ", hp->h_subject);
134 	}
135 	if (gflags & GCC) {
136 #ifndef TIOCSTI
137 		if (!ttyset && hp->h_cc != NULL)
138 			ttyset++, tcsetattr(fileno(stdin), TCSADRAIN, &ttybuf);
139 #endif
140 		hp->h_cc =
141 			extract(readtty("Cc: ", detract(hp->h_cc, 0)), GCC);
142 	}
143 	if (gflags & GBCC) {
144 #ifndef TIOCSTI
145 		if (!ttyset && hp->h_bcc != NULL)
146 			ttyset++, tcsetattr(fileno(stdin), TCSADRAIN, &ttybuf);
147 #endif
148 		hp->h_bcc =
149 			extract(readtty("Bcc: ", detract(hp->h_bcc, 0)), GBCC);
150 	}
151 out:
152 	signal(SIGTSTP, savetstp);
153 	signal(SIGTTOU, savettou);
154 	signal(SIGTTIN, savettin);
155 #ifndef TIOCSTI
156 	ttybuf.c_cc[VERASE] = c_erase;
157 	ttybuf.c_cc[VKILL] = c_kill;
158 	if (ttyset)
159 		tcsetattr(fileno(stdin), TCSADRAIN, &ttybuf);
160 	signal(SIGQUIT, savequit);
161 #else
162 # ifdef		TIOCEXT
163 	if (extproc) {
164 		flag = 1;
165 		if (ioctl(fileno(stdin), TIOCEXT, &flag) < 0)
166 			warn("TIOCEXT: on");
167 	}
168 # endif	/* TIOCEXT */
169 #endif
170 	signal(SIGINT, saveint);
171 	return(errs);
172 }
173 
174 /*
175  * Read up a header from standard input.
176  * The source string has the preliminary contents to
177  * be read.
178  *
179  */
180 
181 char *
182 readtty(char pr[], char src[])
183 {
184 	char ch, canonb[BUFSIZ];
185 	int c;
186 	char *cp, *cp2;
187 #if __GNUC__
188 	/* Avoid longjmp clobbering */
189 	(void)&c;
190 	(void)&cp2;
191 #endif
192 
193 	fputs(pr, stdout);
194 	fflush(stdout);
195 	if (src != NULL && strlen(src) > BUFSIZ - 2) {
196 		printf("too long to edit\n");
197 		return(src);
198 	}
199 #ifndef TIOCSTI
200 	if (src != NULL)
201 		cp = copy(src, canonb);
202 	else
203 		cp = copy("", canonb);
204 	fputs(canonb, stdout);
205 	fflush(stdout);
206 #else
207 	cp = src == NULL ? "" : src;
208 	while ((c = *cp++) != '\0') {
209 		if ((c_erase != _POSIX_VDISABLE && c == c_erase) ||
210 		    (c_kill != _POSIX_VDISABLE && c == c_kill)) {
211 			ch = '\\';
212 			ioctl(0, TIOCSTI, &ch);
213 		}
214 		ch = c;
215 		ioctl(0, TIOCSTI, &ch);
216 	}
217 	cp = canonb;
218 	*cp = 0;
219 #endif
220 	cp2 = cp;
221 	while (cp2 < canonb + BUFSIZ)
222 		*cp2++ = 0;
223 	cp2 = cp;
224 	if (setjmp(rewrite))
225 		goto redo;
226 	signal(SIGTSTP, ttystop);
227 	signal(SIGTTOU, ttystop);
228 	signal(SIGTTIN, ttystop);
229 	clearerr(stdin);
230 	while (cp2 < canonb + BUFSIZ) {
231 		c = getc(stdin);
232 		if (c == EOF || c == '\n')
233 			break;
234 		*cp2++ = c;
235 	}
236 	*cp2 = 0;
237 	signal(SIGTSTP, SIG_DFL);
238 	signal(SIGTTOU, SIG_DFL);
239 	signal(SIGTTIN, SIG_DFL);
240 	if (c == EOF && ferror(stdin)) {
241 redo:
242 		cp = strlen(canonb) > 0 ? canonb : NULL;
243 		clearerr(stdin);
244 		return(readtty(pr, cp));
245 	}
246 #ifndef TIOCSTI
247 	if (cp == NULL || *cp == '\0')
248 		return(src);
249 	cp2 = cp;
250 	if (!ttyset)
251 		return(strlen(canonb) > 0 ? savestr(canonb) : NULL);
252 	while (*cp != '\0') {
253 		c = *cp++;
254 		if (c_erase != _POSIX_VDISABLE && c == c_erase) {
255 			if (cp2 == canonb)
256 				continue;
257 			if (cp2[-1] == '\\') {
258 				cp2[-1] = c;
259 				continue;
260 			}
261 			cp2--;
262 			continue;
263 		}
264 		if (c_kill != _POSIX_VDISABLE && c == c_kill) {
265 			if (cp2 == canonb)
266 				continue;
267 			if (cp2[-1] == '\\') {
268 				cp2[-1] = c;
269 				continue;
270 			}
271 			cp2 = canonb;
272 			continue;
273 		}
274 		*cp2++ = c;
275 	}
276 	*cp2 = '\0';
277 #endif
278 	if (equal("", canonb))
279 		return(NULL);
280 	return(savestr(canonb));
281 }
282 
283 /*
284  * Receipt continuation.
285  */
286 void
287 ttystop(int s)
288 {
289 	sig_t old_action = signal(s, SIG_DFL);
290 	sigset_t nset;
291 
292 	sigemptyset(&nset);
293 	sigaddset(&nset, s);
294 	sigprocmask(SIG_BLOCK, &nset, NULL);
295 	kill(0, s);
296 	sigprocmask(SIG_UNBLOCK, &nset, NULL);
297 	signal(s, old_action);
298 	longjmp(rewrite, 1);
299 }
300 
301 /*ARGSUSED*/
302 void
303 ttyint(int s)
304 {
305 	longjmp(intjmp, 1);
306 }
307