xref: /netbsd-src/usr.bin/mail/lex.c (revision fdecd6a253f999ae92b139670d9e15cc9df4497c)
1 /*	$NetBSD: lex.c,v 1.10 1997/05/17 19:55:13 pk 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. All advertising materials mentioning features or use of this software
16  *    must display the following acknowledgement:
17  *	This product includes software developed by the University of
18  *	California, Berkeley and its contributors.
19  * 4. Neither the name of the University nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  */
35 
36 #ifndef lint
37 #if 0
38 static char sccsid[] = "@(#)lex.c	8.2 (Berkeley) 4/20/95";
39 #else
40 static char rcsid[] = "$NetBSD: lex.c,v 1.10 1997/05/17 19:55:13 pk Exp $";
41 #endif
42 #endif /* not lint */
43 
44 #include "rcv.h"
45 #include <errno.h>
46 #include <fcntl.h>
47 #include "extern.h"
48 
49 /*
50  * Mail -- a mail program
51  *
52  * Lexical processing of commands.
53  */
54 
55 char	*prompt = "& ";
56 
57 /*
58  * Set up editing on the given file name.
59  * If the first character of name is %, we are considered to be
60  * editing the file, otherwise we are reading our mail which has
61  * signficance for mbox and so forth.
62  */
63 int
64 setfile(name)
65 	char *name;
66 {
67 	FILE *ibuf;
68 	int i;
69 	struct stat stb;
70 	char isedit = *name != '%';
71 	char *who = name[1] ? name + 1 : myname;
72 	static int shudclob;
73 	extern char *tempMesg;
74 	extern int errno;
75 
76 	if ((name = expand(name)) == NOSTR)
77 		return -1;
78 
79 	if ((ibuf = Fopen(name, "r")) == NULL) {
80 		if (!isedit && errno == ENOENT)
81 			goto nomail;
82 		perror(name);
83 		return(-1);
84 	}
85 
86 	if (fstat(fileno(ibuf), &stb) < 0) {
87 		perror("fstat");
88 		Fclose(ibuf);
89 		return (-1);
90 	}
91 
92 	switch (stb.st_mode & S_IFMT) {
93 	case S_IFDIR:
94 		Fclose(ibuf);
95 		errno = EISDIR;
96 		perror(name);
97 		return (-1);
98 
99 	case S_IFREG:
100 		break;
101 
102 	default:
103 		Fclose(ibuf);
104 		errno = EINVAL;
105 		perror(name);
106 		return (-1);
107 	}
108 
109 	/*
110 	 * Looks like all will be well.  We must now relinquish our
111 	 * hold on the current set of stuff.  Must hold signals
112 	 * while we are reading the new file, else we will ruin
113 	 * the message[] data structure.
114 	 */
115 
116 	holdsigs();
117 	if (shudclob)
118 		quit();
119 
120 	/*
121 	 * Copy the messages into /tmp
122 	 * and set pointers.
123 	 */
124 
125 	readonly = 0;
126 	if ((i = open(name, 1)) < 0)
127 		readonly++;
128 	else
129 		close(i);
130 	if (shudclob) {
131 		fclose(itf);
132 		fclose(otf);
133 	}
134 	shudclob = 1;
135 	edit = isedit;
136 	strcpy(prevfile, mailname);
137 	if (name != mailname)
138 		strcpy(mailname, name);
139 	mailsize = fsize(ibuf);
140 	if ((otf = fopen(tempMesg, "w")) == NULL) {
141 		perror(tempMesg);
142 		exit(1);
143 	}
144 	(void) fcntl(fileno(otf), F_SETFD, 1);
145 	if ((itf = fopen(tempMesg, "r")) == NULL) {
146 		perror(tempMesg);
147 		exit(1);
148 	}
149 	(void) fcntl(fileno(itf), F_SETFD, 1);
150 	rm(tempMesg);
151 	setptr(ibuf, 0);
152 	setmsize(msgCount);
153 	/*
154 	 * New mail may have arrived while we were reading
155 	 * the mail file, so reset mailsize to be where
156 	 * we really are in the file...
157 	 */
158 	mailsize = ftell(ibuf);
159 	Fclose(ibuf);
160 	relsesigs();
161 	sawcom = 0;
162 	if (!edit && msgCount == 0) {
163 nomail:
164 		fprintf(stderr, "No mail for %s\n", who);
165 		return -1;
166 	}
167 	return(0);
168 }
169 
170 /*
171  * Incorporate any new mail that has arrived since we first
172  * started reading mail.
173  */
174 int
175 incfile()
176 {
177 	int newsize;
178 	int omsgCount = msgCount;
179 	FILE *ibuf;
180 
181 	ibuf = Fopen(mailname, "r");
182 	if (ibuf == NULL)
183 		return -1;
184 	holdsigs();
185 	newsize = fsize(ibuf);
186 	if (newsize == 0)
187 		return -1;		/* mail box is now empty??? */
188 	if (newsize < mailsize)
189 		return -1;              /* mail box has shrunk??? */
190 	if (newsize == mailsize)
191 		return 0;               /* no new mail */
192 	setptr(ibuf, mailsize);
193 	setmsize(msgCount);
194 	mailsize = ftell(ibuf);
195 	Fclose(ibuf);
196 	relsesigs();
197 	return(msgCount - omsgCount);
198 }
199 
200 int	*msgvec;
201 int	reset_on_stop;			/* do a reset() if stopped */
202 
203 /*
204  * Interpret user commands one by one.  If standard input is not a tty,
205  * print no prompt.
206  */
207 void
208 commands()
209 {
210 	int eofloop = 0;
211 	register int n;
212 	char linebuf[LINESIZE];
213 #if __GNUC__
214 	/* Avoid longjmp clobbering */
215 	(void) &eofloop;
216 #endif
217 
218 	if (!sourcing) {
219 		if (signal(SIGINT, SIG_IGN) != SIG_IGN)
220 			signal(SIGINT, intr);
221 		if (signal(SIGHUP, SIG_IGN) != SIG_IGN)
222 			signal(SIGHUP, hangup);
223 		signal(SIGTSTP, stop);
224 		signal(SIGTTOU, stop);
225 		signal(SIGTTIN, stop);
226 	}
227 	setexit();
228 	for (;;) {
229 		/*
230 		 * Print the prompt, if needed.  Clear out
231 		 * string space, and flush the output.
232 		 */
233 		if (!sourcing && value("interactive") != NOSTR) {
234 			if ((value("autoinc") != NOSTR) && (incfile() > 0))
235 				printf("New mail has arrived.\n");
236 			reset_on_stop = 1;
237 			printf(prompt);
238 		}
239 		fflush(stdout);
240 		sreset();
241 		/*
242 		 * Read a line of commands from the current input
243 		 * and handle end of file specially.
244 		 */
245 		n = 0;
246 		for (;;) {
247 			if (readline(input, &linebuf[n], LINESIZE - n) < 0) {
248 				if (n == 0)
249 					n = -1;
250 				break;
251 			}
252 			if ((n = strlen(linebuf)) == 0)
253 				break;
254 			n--;
255 			if (linebuf[n] != '\\')
256 				break;
257 			linebuf[n++] = ' ';
258 		}
259 		reset_on_stop = 0;
260 		if (n < 0) {
261 				/* eof */
262 			if (loading)
263 				break;
264 			if (sourcing) {
265 				unstack();
266 				continue;
267 			}
268 			if (value("interactive") != NOSTR &&
269 			    value("ignoreeof") != NOSTR &&
270 			    ++eofloop < 25) {
271 				printf("Use \"quit\" to quit.\n");
272 				continue;
273 			}
274 			break;
275 		}
276 		eofloop = 0;
277 		if (execute(linebuf, 0))
278 			break;
279 	}
280 }
281 
282 /*
283  * Execute a single command.
284  * Command functions return 0 for success, 1 for error, and -1
285  * for abort.  A 1 or -1 aborts a load or source.  A -1 aborts
286  * the interactive command loop.
287  * Contxt is non-zero if called while composing mail.
288  */
289 int
290 execute(linebuf, contxt)
291 	char linebuf[];
292 	int contxt;
293 {
294 	char word[LINESIZE];
295 	char *arglist[MAXARGC];
296 	const struct cmd *com = NULL;
297 	register char *cp, *cp2;
298 	register int c;
299 	int muvec[2];
300 	int e = 1;
301 
302 	/*
303 	 * Strip the white space away from the beginning
304 	 * of the command, then scan out a word, which
305 	 * consists of anything except digits and white space.
306 	 *
307 	 * Handle ! escapes differently to get the correct
308 	 * lexical conventions.
309 	 */
310 
311 	for (cp = linebuf; isspace(*cp); cp++)
312 		;
313 	if (*cp == '!') {
314 		if (sourcing) {
315 			printf("Can't \"!\" while sourcing\n");
316 			goto out;
317 		}
318 		shell(cp+1);
319 		return(0);
320 	}
321 	cp2 = word;
322 	while (*cp && index(" \t0123456789$^.:/-+*'\"", *cp) == NOSTR)
323 		*cp2++ = *cp++;
324 	*cp2 = '\0';
325 
326 	/*
327 	 * Look up the command; if not found, bitch.
328 	 * Normally, a blank command would map to the
329 	 * first command in the table; while sourcing,
330 	 * however, we ignore blank lines to eliminate
331 	 * confusion.
332 	 */
333 
334 	if (sourcing && *word == '\0')
335 		return(0);
336 	com = lex(word);
337 	if (com == NONE) {
338 		printf("Unknown command: \"%s\"\n", word);
339 		goto out;
340 	}
341 
342 	/*
343 	 * See if we should execute the command -- if a conditional
344 	 * we always execute it, otherwise, check the state of cond.
345 	 */
346 
347 	if ((com->c_argtype & F) == 0)
348 		if ((cond == CRCV && !rcvmode) || (cond == CSEND && rcvmode))
349 			return(0);
350 
351 	/*
352 	 * Process the arguments to the command, depending
353 	 * on the type he expects.  Default to an error.
354 	 * If we are sourcing an interactive command, it's
355 	 * an error.
356 	 */
357 
358 	if (!rcvmode && (com->c_argtype & M) == 0) {
359 		printf("May not execute \"%s\" while sending\n",
360 		    com->c_name);
361 		goto out;
362 	}
363 	if (sourcing && com->c_argtype & I) {
364 		printf("May not execute \"%s\" while sourcing\n",
365 		    com->c_name);
366 		goto out;
367 	}
368 	if (readonly && com->c_argtype & W) {
369 		printf("May not execute \"%s\" -- message file is read only\n",
370 		   com->c_name);
371 		goto out;
372 	}
373 	if (contxt && com->c_argtype & R) {
374 		printf("Cannot recursively invoke \"%s\"\n", com->c_name);
375 		goto out;
376 	}
377 	switch (com->c_argtype & ~(F|P|I|M|T|W|R)) {
378 	case MSGLIST:
379 		/*
380 		 * A message list defaulting to nearest forward
381 		 * legal message.
382 		 */
383 		if (msgvec == 0) {
384 			printf("Illegal use of \"message list\"\n");
385 			break;
386 		}
387 		if ((c = getmsglist(cp, msgvec, com->c_msgflag)) < 0)
388 			break;
389 		if (c  == 0) {
390 			*msgvec = first(com->c_msgflag,
391 				com->c_msgmask);
392 			msgvec[1] = 0;
393 		}
394 		if (*msgvec == 0) {
395 			printf("No applicable messages\n");
396 			break;
397 		}
398 		e = (*com->c_func)(msgvec);
399 		break;
400 
401 	case NDMLIST:
402 		/*
403 		 * A message list with no defaults, but no error
404 		 * if none exist.
405 		 */
406 		if (msgvec == 0) {
407 			printf("Illegal use of \"message list\"\n");
408 			break;
409 		}
410 		if (getmsglist(cp, msgvec, com->c_msgflag) < 0)
411 			break;
412 		e = (*com->c_func)(msgvec);
413 		break;
414 
415 	case STRLIST:
416 		/*
417 		 * Just the straight string, with
418 		 * leading blanks removed.
419 		 */
420 		while (isspace(*cp))
421 			cp++;
422 		e = (*com->c_func)(cp);
423 		break;
424 
425 	case RAWLIST:
426 		/*
427 		 * A vector of strings, in shell style.
428 		 */
429 		if ((c = getrawlist(cp, arglist,
430 				sizeof arglist / sizeof *arglist)) < 0)
431 			break;
432 		if (c < com->c_minargs) {
433 			printf("%s requires at least %d arg(s)\n",
434 				com->c_name, com->c_minargs);
435 			break;
436 		}
437 		if (c > com->c_maxargs) {
438 			printf("%s takes no more than %d arg(s)\n",
439 				com->c_name, com->c_maxargs);
440 			break;
441 		}
442 		e = (*com->c_func)(arglist);
443 		break;
444 
445 	case NOLIST:
446 		/*
447 		 * Just the constant zero, for exiting,
448 		 * eg.
449 		 */
450 		e = (*com->c_func)(0);
451 		break;
452 
453 	default:
454 		panic("Unknown argtype");
455 	}
456 
457 out:
458 	/*
459 	 * Exit the current source file on
460 	 * error.
461 	 */
462 	if (e) {
463 		if (e < 0)
464 			return 1;
465 		if (loading)
466 			return 1;
467 		if (sourcing)
468 			unstack();
469 		return 0;
470 	}
471 	if (com == NULL)
472 		return(0);
473 	if (value("autoprint") != NOSTR && com->c_argtype & P)
474 		if ((dot->m_flag & MDELETED) == 0) {
475 			muvec[0] = dot - &message[0] + 1;
476 			muvec[1] = 0;
477 			type(muvec);
478 		}
479 	if (!sourcing && (com->c_argtype & T) == 0)
480 		sawcom = 1;
481 	return(0);
482 }
483 
484 /*
485  * Set the size of the message vector used to construct argument
486  * lists to message list functions.
487  */
488 void
489 setmsize(sz)
490 	int sz;
491 {
492 
493 	if (msgvec != 0)
494 		free((char *) msgvec);
495 	msgvec = (int *) calloc((unsigned) (sz + 1), sizeof *msgvec);
496 }
497 
498 /*
499  * Find the correct command in the command table corresponding
500  * to the passed command "word"
501  */
502 
503 const struct cmd *
504 lex(word)
505 	char word[];
506 {
507 	extern const struct cmd cmdtab[];
508 	register const struct cmd *cp;
509 
510 	for (cp = &cmdtab[0]; cp->c_name != NOSTR; cp++)
511 		if (isprefix(word, cp->c_name))
512 			return(cp);
513 	return(NONE);
514 }
515 
516 /*
517  * Determine if as1 is a valid prefix of as2.
518  * Return true if yep.
519  */
520 int
521 isprefix(as1, as2)
522 	char *as1, *as2;
523 {
524 	register char *s1, *s2;
525 
526 	s1 = as1;
527 	s2 = as2;
528 	while (*s1++ == *s2)
529 		if (*s2++ == '\0')
530 			return(1);
531 	return(*--s1 == '\0');
532 }
533 
534 /*
535  * The following gets called on receipt of an interrupt.  This is
536  * to abort printout of a command, mainly.
537  * Dispatching here when command() is inactive crashes rcv.
538  * Close all open files except 0, 1, 2, and the temporary.
539  * Also, unstack all source files.
540  */
541 
542 int	inithdr;			/* am printing startup headers */
543 
544 /*ARGSUSED*/
545 void
546 intr(s)
547 	int s;
548 {
549 
550 	noreset = 0;
551 	if (!inithdr)
552 		sawcom++;
553 	inithdr = 0;
554 	while (sourcing)
555 		unstack();
556 
557 	close_all_files();
558 
559 	if (image >= 0) {
560 		close(image);
561 		image = -1;
562 	}
563 	fprintf(stderr, "Interrupt\n");
564 	reset(0);
565 }
566 
567 /*
568  * When we wake up after ^Z, reprint the prompt.
569  */
570 void
571 stop(s)
572 	int s;
573 {
574 	sig_t old_action = signal(s, SIG_DFL);
575 	sigset_t nset;
576 
577 	sigemptyset(&nset);
578 	sigaddset(&nset, s);
579 	sigprocmask(SIG_UNBLOCK, &nset, NULL);
580 	kill(0, s);
581 	sigprocmask(SIG_BLOCK, &nset, NULL);
582 	signal(s, old_action);
583 	if (reset_on_stop) {
584 		reset_on_stop = 0;
585 		reset(0);
586 	}
587 }
588 
589 /*
590  * Branch here on hangup signal and simulate "exit".
591  */
592 /*ARGSUSED*/
593 void
594 hangup(s)
595 	int s;
596 {
597 
598 	/* nothing to do? */
599 	exit(1);
600 }
601 
602 /*
603  * Announce the presence of the current Mail version,
604  * give the message count, and print a header listing.
605  */
606 void
607 announce()
608 {
609 	int vec[2], mdot;
610 
611 	mdot = newfileinfo(0);
612 	vec[0] = mdot;
613 	vec[1] = 0;
614 	dot = &message[mdot - 1];
615 	if (msgCount > 0 && value("noheader") == NOSTR) {
616 		inithdr++;
617 		headers(vec);
618 		inithdr = 0;
619 	}
620 }
621 
622 /*
623  * Announce information about the file we are editing.
624  * Return a likely place to set dot.
625  */
626 int
627 newfileinfo(omsgCount)
628 	int omsgCount;
629 {
630 	register struct message *mp;
631 	register int u, n, mdot, d, s, l;
632 	char fname[PATHSIZE], zname[PATHSIZE], *ename;
633 
634 	for (mp = &message[omsgCount]; mp < &message[msgCount]; mp++)
635 		if (mp->m_flag & MNEW)
636 			break;
637 	if (mp >= &message[msgCount])
638 		for (mp = &message[omsgCount]; mp < &message[msgCount]; mp++)
639 			if ((mp->m_flag & MREAD) == 0)
640 				break;
641 	if (mp < &message[msgCount])
642 		mdot = mp - &message[0] + 1;
643 	else
644 		mdot = omsgCount + 1;
645 	s = d = 0;
646 	for (mp = &message[0], n = 0, u = 0; mp < &message[msgCount]; mp++) {
647 		if (mp->m_flag & MNEW)
648 			n++;
649 		if ((mp->m_flag & MREAD) == 0)
650 			u++;
651 		if (mp->m_flag & MDELETED)
652 			d++;
653 		if (mp->m_flag & MSAVED)
654 			s++;
655 	}
656 	ename = mailname;
657 	if (getfold(fname) >= 0) {
658 		l = strlen(fname);
659 		if (l < PATHSIZE - 1)
660 			fname[l++] = '/';
661 		if (strncmp(fname, mailname, l) == 0) {
662 			snprintf(zname, PATHSIZE, "+%s",
663 			    mailname + l);
664 			ename = zname;
665 		}
666 	}
667 	printf("\"%s\": ", ename);
668 	if (msgCount == 1)
669 		printf("1 message");
670 	else
671 		printf("%d messages", msgCount);
672 	if (n > 0)
673 		printf(" %d new", n);
674 	if (u-n > 0)
675 		printf(" %d unread", u);
676 	if (d > 0)
677 		printf(" %d deleted", d);
678 	if (s > 0)
679 		printf(" %d saved", s);
680 	if (readonly)
681 		printf(" [Read only]");
682 	printf("\n");
683 	return(mdot);
684 }
685 
686 /*
687  * Print the current version number.
688  */
689 
690 /*ARGSUSED*/
691 int
692 pversion(v)
693 	void *v;
694 {
695 	extern char *version;
696 
697 	printf("Version %s\n", version);
698 	return(0);
699 }
700 
701 /*
702  * Load a file of user definitions.
703  */
704 void
705 load(name)
706 	char *name;
707 {
708 	register FILE *in, *oldin;
709 
710 	if ((in = Fopen(name, "r")) == NULL)
711 		return;
712 	oldin = input;
713 	input = in;
714 	loading = 1;
715 	sourcing = 1;
716 	commands();
717 	loading = 0;
718 	sourcing = 0;
719 	input = oldin;
720 	Fclose(in);
721 }
722