xref: /netbsd-src/usr.bin/mail/lex.c (revision d9158b13b5dfe46201430699a3f7a235ecf28df3)
1 /*
2  * Copyright (c) 1980 Regents of the University of California.
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by the University of
16  *	California, Berkeley and its contributors.
17  * 4. Neither the name of the University 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 REGENTS 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 REGENTS 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 #ifndef lint
35 /*static char sccsid[] = "from: @(#)lex.c	5.23 (Berkeley) 4/1/91";*/
36 static char rcsid[] = "$Id: lex.c,v 1.3 1994/05/22 02:57:36 jtc Exp $";
37 #endif /* not lint */
38 
39 #include "rcv.h"
40 #include <sys/stat.h>
41 #include <errno.h>
42 
43 /*
44  * Mail -- a mail program
45  *
46  * Lexical processing of commands.
47  */
48 
49 char	*prompt = "& ";
50 
51 /*
52  * Set up editing on the given file name.
53  * If the first character of name is %, we are considered to be
54  * editing the file, otherwise we are reading our mail which has
55  * signficance for mbox and so forth.
56  */
57 setfile(name)
58 	char *name;
59 {
60 	FILE *ibuf;
61 	int i;
62 	struct stat stb;
63 	char isedit = *name != '%';
64 	char *who = name[1] ? name + 1 : myname;
65 	static int shudclob;
66 	extern char tempMesg[];
67 	extern int errno;
68 
69 	if ((name = expand(name)) == NOSTR)
70 		return -1;
71 
72 	if ((ibuf = Fopen(name, "r")) == NULL) {
73 		if (!isedit && errno == ENOENT)
74 			goto nomail;
75 		perror(name);
76 		return(-1);
77 	}
78 
79 	if (fstat(fileno(ibuf), &stb) < 0) {
80 		perror("fstat");
81 		Fclose(ibuf);
82 		return (-1);
83 	}
84 
85 	switch (stb.st_mode & S_IFMT) {
86 	case S_IFDIR:
87 		Fclose(ibuf);
88 		errno = EISDIR;
89 		perror(name);
90 		return (-1);
91 
92 	case S_IFREG:
93 		break;
94 
95 	default:
96 		Fclose(ibuf);
97 		errno = EINVAL;
98 		perror(name);
99 		return (-1);
100 	}
101 
102 	/*
103 	 * Looks like all will be well.  We must now relinquish our
104 	 * hold on the current set of stuff.  Must hold signals
105 	 * while we are reading the new file, else we will ruin
106 	 * the message[] data structure.
107 	 */
108 
109 	holdsigs();
110 	if (shudclob)
111 		quit();
112 
113 	/*
114 	 * Copy the messages into /tmp
115 	 * and set pointers.
116 	 */
117 
118 	readonly = 0;
119 	if ((i = open(name, 1)) < 0)
120 		readonly++;
121 	else
122 		close(i);
123 	if (shudclob) {
124 		fclose(itf);
125 		fclose(otf);
126 	}
127 	shudclob = 1;
128 	edit = isedit;
129 	strcpy(prevfile, mailname);
130 	if (name != mailname)
131 		strcpy(mailname, name);
132 	mailsize = fsize(ibuf);
133 	if ((otf = fopen(tempMesg, "w")) == NULL) {
134 		perror(tempMesg);
135 		exit(1);
136 	}
137 	if ((itf = fopen(tempMesg, "r")) == NULL) {
138 		perror(tempMesg);
139 		exit(1);
140 	}
141 	rm(tempMesg);
142 	setptr(ibuf);
143 	setmsize(msgCount);
144 	Fclose(ibuf);
145 	relsesigs();
146 	sawcom = 0;
147 	if (!edit && msgCount == 0) {
148 nomail:
149 		fprintf(stderr, "No mail for %s\n", who);
150 		return -1;
151 	}
152 	return(0);
153 }
154 
155 int	*msgvec;
156 int	reset_on_stop;			/* do a reset() if stopped */
157 
158 /*
159  * Interpret user commands one by one.  If standard input is not a tty,
160  * print no prompt.
161  */
162 commands()
163 {
164 	int eofloop = 0;
165 	register int n;
166 	char linebuf[LINESIZE];
167 	void intr(), stop(), hangup();
168 
169 	if (!sourcing) {
170 		if (signal(SIGINT, SIG_IGN) != SIG_IGN)
171 			signal(SIGINT, intr);
172 		if (signal(SIGHUP, SIG_IGN) != SIG_IGN)
173 			signal(SIGHUP, hangup);
174 		signal(SIGTSTP, stop);
175 		signal(SIGTTOU, stop);
176 		signal(SIGTTIN, stop);
177 	}
178 	setexit();
179 	for (;;) {
180 		/*
181 		 * Print the prompt, if needed.  Clear out
182 		 * string space, and flush the output.
183 		 */
184 		if (!sourcing && value("interactive") != NOSTR) {
185 			reset_on_stop = 1;
186 			printf(prompt);
187 		}
188 		fflush(stdout);
189 		sreset();
190 		/*
191 		 * Read a line of commands from the current input
192 		 * and handle end of file specially.
193 		 */
194 		n = 0;
195 		for (;;) {
196 			if (readline(input, &linebuf[n], LINESIZE - n) < 0) {
197 				if (n == 0)
198 					n = -1;
199 				break;
200 			}
201 			if ((n = strlen(linebuf)) == 0)
202 				break;
203 			n--;
204 			if (linebuf[n] != '\\')
205 				break;
206 			linebuf[n++] = ' ';
207 		}
208 		reset_on_stop = 0;
209 		if (n < 0) {
210 				/* eof */
211 			if (loading)
212 				break;
213 			if (sourcing) {
214 				unstack();
215 				continue;
216 			}
217 			if (value("interactive") != NOSTR &&
218 			    value("ignoreeof") != NOSTR &&
219 			    ++eofloop < 25) {
220 				printf("Use \"quit\" to quit.\n");
221 				continue;
222 			}
223 			break;
224 		}
225 		eofloop = 0;
226 		if (execute(linebuf, 0))
227 			break;
228 	}
229 }
230 
231 /*
232  * Execute a single command.
233  * Command functions return 0 for success, 1 for error, and -1
234  * for abort.  A 1 or -1 aborts a load or source.  A -1 aborts
235  * the interactive command loop.
236  * Contxt is non-zero if called while composing mail.
237  */
238 execute(linebuf, contxt)
239 	char linebuf[];
240 {
241 	char word[LINESIZE];
242 	char *arglist[MAXARGC];
243 	struct cmd *com;
244 	register char *cp, *cp2;
245 	register int c;
246 	int muvec[2];
247 	int e = 1;
248 
249 	/*
250 	 * Strip the white space away from the beginning
251 	 * of the command, then scan out a word, which
252 	 * consists of anything except digits and white space.
253 	 *
254 	 * Handle ! escapes differently to get the correct
255 	 * lexical conventions.
256 	 */
257 
258 	for (cp = linebuf; isspace(*cp); cp++)
259 		;
260 	if (*cp == '!') {
261 		if (sourcing) {
262 			printf("Can't \"!\" while sourcing\n");
263 			goto out;
264 		}
265 		shell(cp+1);
266 		return(0);
267 	}
268 	cp2 = word;
269 	while (*cp && index(" \t0123456789$^.:/-+*'\"", *cp) == NOSTR)
270 		*cp2++ = *cp++;
271 	*cp2 = '\0';
272 
273 	/*
274 	 * Look up the command; if not found, bitch.
275 	 * Normally, a blank command would map to the
276 	 * first command in the table; while sourcing,
277 	 * however, we ignore blank lines to eliminate
278 	 * confusion.
279 	 */
280 
281 	if (sourcing && *word == '\0')
282 		return(0);
283 	com = lex(word);
284 	if (com == NONE) {
285 		printf("Unknown command: \"%s\"\n", word);
286 		goto out;
287 	}
288 
289 	/*
290 	 * See if we should execute the command -- if a conditional
291 	 * we always execute it, otherwise, check the state of cond.
292 	 */
293 
294 	if ((com->c_argtype & F) == 0)
295 		if (cond == CRCV && !rcvmode || cond == CSEND && rcvmode)
296 			return(0);
297 
298 	/*
299 	 * Process the arguments to the command, depending
300 	 * on the type he expects.  Default to an error.
301 	 * If we are sourcing an interactive command, it's
302 	 * an error.
303 	 */
304 
305 	if (!rcvmode && (com->c_argtype & M) == 0) {
306 		printf("May not execute \"%s\" while sending\n",
307 		    com->c_name);
308 		goto out;
309 	}
310 	if (sourcing && com->c_argtype & I) {
311 		printf("May not execute \"%s\" while sourcing\n",
312 		    com->c_name);
313 		goto out;
314 	}
315 	if (readonly && com->c_argtype & W) {
316 		printf("May not execute \"%s\" -- message file is read only\n",
317 		   com->c_name);
318 		goto out;
319 	}
320 	if (contxt && com->c_argtype & R) {
321 		printf("Cannot recursively invoke \"%s\"\n", com->c_name);
322 		goto out;
323 	}
324 	switch (com->c_argtype & ~(F|P|I|M|T|W|R)) {
325 	case MSGLIST:
326 		/*
327 		 * A message list defaulting to nearest forward
328 		 * legal message.
329 		 */
330 		if (msgvec == 0) {
331 			printf("Illegal use of \"message list\"\n");
332 			break;
333 		}
334 		if ((c = getmsglist(cp, msgvec, com->c_msgflag)) < 0)
335 			break;
336 		if (c  == 0) {
337 			*msgvec = first(com->c_msgflag,
338 				com->c_msgmask);
339 			msgvec[1] = NULL;
340 		}
341 		if (*msgvec == NULL) {
342 			printf("No applicable messages\n");
343 			break;
344 		}
345 		e = (*com->c_func)(msgvec);
346 		break;
347 
348 	case NDMLIST:
349 		/*
350 		 * A message list with no defaults, but no error
351 		 * if none exist.
352 		 */
353 		if (msgvec == 0) {
354 			printf("Illegal use of \"message list\"\n");
355 			break;
356 		}
357 		if (getmsglist(cp, msgvec, com->c_msgflag) < 0)
358 			break;
359 		e = (*com->c_func)(msgvec);
360 		break;
361 
362 	case STRLIST:
363 		/*
364 		 * Just the straight string, with
365 		 * leading blanks removed.
366 		 */
367 		while (isspace(*cp))
368 			cp++;
369 		e = (*com->c_func)(cp);
370 		break;
371 
372 	case RAWLIST:
373 		/*
374 		 * A vector of strings, in shell style.
375 		 */
376 		if ((c = getrawlist(cp, arglist,
377 				sizeof arglist / sizeof *arglist)) < 0)
378 			break;
379 		if (c < com->c_minargs) {
380 			printf("%s requires at least %d arg(s)\n",
381 				com->c_name, com->c_minargs);
382 			break;
383 		}
384 		if (c > com->c_maxargs) {
385 			printf("%s takes no more than %d arg(s)\n",
386 				com->c_name, com->c_maxargs);
387 			break;
388 		}
389 		e = (*com->c_func)(arglist);
390 		break;
391 
392 	case NOLIST:
393 		/*
394 		 * Just the constant zero, for exiting,
395 		 * eg.
396 		 */
397 		e = (*com->c_func)(0);
398 		break;
399 
400 	default:
401 		panic("Unknown argtype");
402 	}
403 
404 out:
405 	/*
406 	 * Exit the current source file on
407 	 * error.
408 	 */
409 	if (e) {
410 		if (e < 0)
411 			return 1;
412 		if (loading)
413 			return 1;
414 		if (sourcing)
415 			unstack();
416 		return 0;
417 	}
418 	if (value("autoprint") != NOSTR && com->c_argtype & P)
419 		if ((dot->m_flag & MDELETED) == 0) {
420 			muvec[0] = dot - &message[0] + 1;
421 			muvec[1] = 0;
422 			type(muvec);
423 		}
424 	if (!sourcing && (com->c_argtype & T) == 0)
425 		sawcom = 1;
426 	return(0);
427 }
428 
429 /*
430  * Set the size of the message vector used to construct argument
431  * lists to message list functions.
432  */
433 
434 setmsize(sz)
435 {
436 
437 	if (msgvec != 0)
438 		free((char *) msgvec);
439 	msgvec = (int *) calloc((unsigned) (sz + 1), sizeof *msgvec);
440 }
441 
442 /*
443  * Find the correct command in the command table corresponding
444  * to the passed command "word"
445  */
446 
447 struct cmd *
448 lex(word)
449 	char word[];
450 {
451 	register struct cmd *cp;
452 	extern struct cmd cmdtab[];
453 
454 	for (cp = &cmdtab[0]; cp->c_name != NOSTR; cp++)
455 		if (isprefix(word, cp->c_name))
456 			return(cp);
457 	return(NONE);
458 }
459 
460 /*
461  * Determine if as1 is a valid prefix of as2.
462  * Return true if yep.
463  */
464 
465 isprefix(as1, as2)
466 	char *as1, *as2;
467 {
468 	register char *s1, *s2;
469 
470 	s1 = as1;
471 	s2 = as2;
472 	while (*s1++ == *s2)
473 		if (*s2++ == '\0')
474 			return(1);
475 	return(*--s1 == '\0');
476 }
477 
478 /*
479  * The following gets called on receipt of an interrupt.  This is
480  * to abort printout of a command, mainly.
481  * Dispatching here when command() is inactive crashes rcv.
482  * Close all open files except 0, 1, 2, and the temporary.
483  * Also, unstack all source files.
484  */
485 
486 int	inithdr;			/* am printing startup headers */
487 
488 /*ARGSUSED*/
489 void
490 intr(s)
491 {
492 
493 	noreset = 0;
494 	if (!inithdr)
495 		sawcom++;
496 	inithdr = 0;
497 	while (sourcing)
498 		unstack();
499 
500 	close_all_files();
501 
502 	if (image >= 0) {
503 		close(image);
504 		image = -1;
505 	}
506 	fprintf(stderr, "Interrupt\n");
507 	reset(0);
508 }
509 
510 /*
511  * When we wake up after ^Z, reprint the prompt.
512  */
513 void
514 stop(s)
515 {
516 	sig_t old_action = signal(s, SIG_DFL);
517 
518 	sigsetmask(sigblock(0) & ~sigmask(s));
519 	kill(0, s);
520 	sigblock(sigmask(s));
521 	signal(s, old_action);
522 	if (reset_on_stop) {
523 		reset_on_stop = 0;
524 		reset(0);
525 	}
526 }
527 
528 /*
529  * Branch here on hangup signal and simulate "exit".
530  */
531 /*ARGSUSED*/
532 void
533 hangup(s)
534 {
535 
536 	/* nothing to do? */
537 	exit(1);
538 }
539 
540 /*
541  * Announce the presence of the current Mail version,
542  * give the message count, and print a header listing.
543  */
544 
545 announce()
546 {
547 	int vec[2], mdot;
548 
549 	mdot = newfileinfo();
550 	vec[0] = mdot;
551 	vec[1] = 0;
552 	dot = &message[mdot - 1];
553 	if (msgCount > 0 && value("noheader") == NOSTR) {
554 		inithdr++;
555 		headers(vec);
556 		inithdr = 0;
557 	}
558 }
559 
560 /*
561  * Announce information about the file we are editing.
562  * Return a likely place to set dot.
563  */
564 newfileinfo()
565 {
566 	register struct message *mp;
567 	register int u, n, mdot, d, s;
568 	char fname[BUFSIZ], zname[BUFSIZ], *ename;
569 
570 	for (mp = &message[0]; mp < &message[msgCount]; mp++)
571 		if (mp->m_flag & MNEW)
572 			break;
573 	if (mp >= &message[msgCount])
574 		for (mp = &message[0]; mp < &message[msgCount]; mp++)
575 			if ((mp->m_flag & MREAD) == 0)
576 				break;
577 	if (mp < &message[msgCount])
578 		mdot = mp - &message[0] + 1;
579 	else
580 		mdot = 1;
581 	s = d = 0;
582 	for (mp = &message[0], n = 0, u = 0; mp < &message[msgCount]; mp++) {
583 		if (mp->m_flag & MNEW)
584 			n++;
585 		if ((mp->m_flag & MREAD) == 0)
586 			u++;
587 		if (mp->m_flag & MDELETED)
588 			d++;
589 		if (mp->m_flag & MSAVED)
590 			s++;
591 	}
592 	ename = mailname;
593 	if (getfold(fname) >= 0) {
594 		strcat(fname, "/");
595 		if (strncmp(fname, mailname, strlen(fname)) == 0) {
596 			sprintf(zname, "+%s", mailname + strlen(fname));
597 			ename = zname;
598 		}
599 	}
600 	printf("\"%s\": ", ename);
601 	if (msgCount == 1)
602 		printf("1 message");
603 	else
604 		printf("%d messages", msgCount);
605 	if (n > 0)
606 		printf(" %d new", n);
607 	if (u-n > 0)
608 		printf(" %d unread", u);
609 	if (d > 0)
610 		printf(" %d deleted", d);
611 	if (s > 0)
612 		printf(" %d saved", s);
613 	if (readonly)
614 		printf(" [Read only]");
615 	printf("\n");
616 	return(mdot);
617 }
618 
619 /*
620  * Print the current version number.
621  */
622 
623 /*ARGSUSED*/
624 pversion(e)
625 {
626 	extern char *version;
627 
628 	printf("Version %s\n", version);
629 	return(0);
630 }
631 
632 /*
633  * Load a file of user definitions.
634  */
635 load(name)
636 	char *name;
637 {
638 	register FILE *in, *oldin;
639 
640 	if ((in = Fopen(name, "r")) == NULL)
641 		return;
642 	oldin = input;
643 	input = in;
644 	loading = 1;
645 	sourcing = 1;
646 	commands();
647 	loading = 0;
648 	sourcing = 0;
649 	input = oldin;
650 	Fclose(in);
651 }
652