xref: /netbsd-src/usr.bin/mail/lex.c (revision 4472dbe5e3bd91ef2540bada7a7ca7384627ff9b)
1 /*	$NetBSD: lex.c,v 1.14 2000/01/21 17:08:35 mycroft 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 #include <sys/cdefs.h>
37 #ifndef lint
38 #if 0
39 static char sccsid[] = "@(#)lex.c	8.2 (Berkeley) 4/20/95";
40 #else
41 __RCSID("$NetBSD: lex.c,v 1.14 2000/01/21 17:08:35 mycroft Exp $");
42 #endif
43 #endif /* not lint */
44 
45 #include "rcv.h"
46 #include "extern.h"
47 
48 /*
49  * Mail -- a mail program
50  *
51  * Lexical processing of commands.
52  */
53 
54 char	*prompt = "& ";
55 
56 /*
57  * Set up editing on the given file name.
58  * If the first character of name is %, we are considered to be
59  * editing the file, otherwise we are reading our mail which has
60  * signficance for mbox and so forth.
61  */
62 int
63 setfile(name)
64 	char *name;
65 {
66 	FILE *ibuf;
67 	int i;
68 	struct stat stb;
69 	char isedit = *name != '%' || getuserid(myname) != getuid();
70 	char *who = name[1] ? name + 1 : myname;
71 	static int shudclob;
72 	extern char *tempMesg;
73 
74 	if ((name = expand(name)) == NOSTR)
75 		return -1;
76 
77 	if ((ibuf = Fopen(name, "r")) == NULL) {
78 		if (!isedit && errno == ENOENT)
79 			goto nomail;
80 		perror(name);
81 		return(-1);
82 	}
83 
84 	if (fstat(fileno(ibuf), &stb) < 0) {
85 		perror("fstat");
86 		Fclose(ibuf);
87 		return (-1);
88 	}
89 
90 	switch (stb.st_mode & S_IFMT) {
91 	case S_IFDIR:
92 		Fclose(ibuf);
93 		errno = EISDIR;
94 		perror(name);
95 		return (-1);
96 
97 	case S_IFREG:
98 		break;
99 
100 	default:
101 		Fclose(ibuf);
102 		errno = EINVAL;
103 		perror(name);
104 		return (-1);
105 	}
106 
107 	/*
108 	 * Looks like all will be well.  We must now relinquish our
109 	 * hold on the current set of stuff.  Must hold signals
110 	 * while we are reading the new file, else we will ruin
111 	 * the message[] data structure.
112 	 */
113 
114 	holdsigs();
115 	if (shudclob)
116 		quit();
117 
118 	/*
119 	 * Copy the messages into /tmp
120 	 * and set pointers.
121 	 */
122 
123 	readonly = 0;
124 	if ((i = open(name, 1)) < 0)
125 		readonly++;
126 	else
127 		close(i);
128 	if (shudclob) {
129 		fclose(itf);
130 		fclose(otf);
131 	}
132 	shudclob = 1;
133 	edit = isedit;
134 	strcpy(prevfile, mailname);
135 	if (name != mailname)
136 		strcpy(mailname, name);
137 	mailsize = fsize(ibuf);
138 	if ((otf = fopen(tempMesg, "w")) == NULL) {
139 		perror(tempMesg);
140 		exit(1);
141 	}
142 	(void) fcntl(fileno(otf), F_SETFD, 1);
143 	if ((itf = fopen(tempMesg, "r")) == NULL) {
144 		perror(tempMesg);
145 		exit(1);
146 	}
147 	(void) fcntl(fileno(itf), F_SETFD, 1);
148 	rm(tempMesg);
149 	setptr(ibuf, 0);
150 	setmsize(msgCount);
151 	/*
152 	 * New mail may have arrived while we were reading
153 	 * the mail file, so reset mailsize to be where
154 	 * we really are in the file...
155 	 */
156 	mailsize = ftell(ibuf);
157 	Fclose(ibuf);
158 	relsesigs();
159 	sawcom = 0;
160 	if (!edit && msgCount == 0) {
161 nomail:
162 		fprintf(stderr, "No mail for %s\n", who);
163 		return -1;
164 	}
165 	return(0);
166 }
167 
168 /*
169  * Incorporate any new mail that has arrived since we first
170  * started reading mail.
171  */
172 int
173 incfile()
174 {
175 	int newsize;
176 	int omsgCount = msgCount;
177 	FILE *ibuf;
178 
179 	ibuf = Fopen(mailname, "r");
180 	if (ibuf == NULL)
181 		return -1;
182 	holdsigs();
183 	newsize = fsize(ibuf);
184 	if (newsize == 0)
185 		return -1;		/* mail box is now empty??? */
186 	if (newsize < mailsize)
187 		return -1;              /* mail box has shrunk??? */
188 	if (newsize == mailsize)
189 		return 0;               /* no new mail */
190 	setptr(ibuf, mailsize);
191 	setmsize(msgCount);
192 	mailsize = ftell(ibuf);
193 	Fclose(ibuf);
194 	relsesigs();
195 	return(msgCount - omsgCount);
196 }
197 
198 int	*msgvec;
199 int	reset_on_stop;			/* do a reset() if stopped */
200 
201 /*
202  * Interpret user commands one by one.  If standard input is not a tty,
203  * print no prompt.
204  */
205 void
206 commands()
207 {
208 	int eofloop = 0;
209 	int n;
210 	char linebuf[LINESIZE];
211 #if __GNUC__
212 	/* Avoid longjmp clobbering */
213 	(void) &eofloop;
214 #endif
215 
216 	if (!sourcing) {
217 		if (signal(SIGINT, SIG_IGN) != SIG_IGN)
218 			signal(SIGINT, intr);
219 		if (signal(SIGHUP, SIG_IGN) != SIG_IGN)
220 			signal(SIGHUP, hangup);
221 		signal(SIGTSTP, stop);
222 		signal(SIGTTOU, stop);
223 		signal(SIGTTIN, stop);
224 	}
225 	setexit();
226 	for (;;) {
227 		/*
228 		 * Print the prompt, if needed.  Clear out
229 		 * string space, and flush the output.
230 		 */
231 		if (!sourcing && value("interactive") != NOSTR) {
232 			if ((value("autoinc") != NOSTR) && (incfile() > 0))
233 				printf("New mail has arrived.\n");
234 			reset_on_stop = 1;
235 			printf(prompt);
236 		}
237 		fflush(stdout);
238 		sreset();
239 		/*
240 		 * Read a line of commands from the current input
241 		 * and handle end of file specially.
242 		 */
243 		n = 0;
244 		for (;;) {
245 			if (readline(input, &linebuf[n], LINESIZE - n) < 0) {
246 				if (n == 0)
247 					n = -1;
248 				break;
249 			}
250 			if ((n = strlen(linebuf)) == 0)
251 				break;
252 			n--;
253 			if (linebuf[n] != '\\')
254 				break;
255 			linebuf[n++] = ' ';
256 		}
257 		reset_on_stop = 0;
258 		if (n < 0) {
259 				/* eof */
260 			if (loading)
261 				break;
262 			if (sourcing) {
263 				unstack();
264 				continue;
265 			}
266 			if (value("interactive") != NOSTR &&
267 			    value("ignoreeof") != NOSTR &&
268 			    ++eofloop < 25) {
269 				printf("Use \"quit\" to quit.\n");
270 				continue;
271 			}
272 			break;
273 		}
274 		eofloop = 0;
275 		if (execute(linebuf, 0))
276 			break;
277 	}
278 }
279 
280 /*
281  * Execute a single command.
282  * Command functions return 0 for success, 1 for error, and -1
283  * for abort.  A 1 or -1 aborts a load or source.  A -1 aborts
284  * the interactive command loop.
285  * Contxt is non-zero if called while composing mail.
286  */
287 int
288 execute(linebuf, contxt)
289 	char linebuf[];
290 	int contxt;
291 {
292 	char word[LINESIZE];
293 	char *arglist[MAXARGC];
294 	const struct cmd *com = NULL;
295 	char *cp, *cp2;
296 	int c;
297 	int muvec[2];
298 	int e = 1;
299 
300 	/*
301 	 * Strip the white space away from the beginning
302 	 * of the command, then scan out a word, which
303 	 * consists of anything except digits and white space.
304 	 *
305 	 * Handle ! escapes differently to get the correct
306 	 * lexical conventions.
307 	 */
308 
309 	for (cp = linebuf; isspace((unsigned char)*cp); cp++)
310 		;
311 	if (*cp == '!') {
312 		if (sourcing) {
313 			printf("Can't \"!\" while sourcing\n");
314 			goto out;
315 		}
316 		shell(cp+1);
317 		return(0);
318 	}
319 	cp2 = word;
320 	while (*cp && strchr(" \t0123456789$^.:/-+*'\"", *cp) == NOSTR)
321 		*cp2++ = *cp++;
322 	*cp2 = '\0';
323 
324 	/*
325 	 * Look up the command; if not found, bitch.
326 	 * Normally, a blank command would map to the
327 	 * first command in the table; while sourcing,
328 	 * however, we ignore blank lines to eliminate
329 	 * confusion.
330 	 */
331 
332 	if (sourcing && *word == '\0')
333 		return(0);
334 	com = lex(word);
335 	if (com == NONE) {
336 		printf("Unknown command: \"%s\"\n", word);
337 		goto out;
338 	}
339 
340 	/*
341 	 * See if we should execute the command -- if a conditional
342 	 * we always execute it, otherwise, check the state of cond.
343 	 */
344 
345 	if ((com->c_argtype & F) == 0)
346 		if ((cond == CRCV && !rcvmode) || (cond == CSEND && rcvmode))
347 			return(0);
348 
349 	/*
350 	 * Process the arguments to the command, depending
351 	 * on the type he expects.  Default to an error.
352 	 * If we are sourcing an interactive command, it's
353 	 * an error.
354 	 */
355 
356 	if (!rcvmode && (com->c_argtype & M) == 0) {
357 		printf("May not execute \"%s\" while sending\n",
358 		    com->c_name);
359 		goto out;
360 	}
361 	if (sourcing && com->c_argtype & I) {
362 		printf("May not execute \"%s\" while sourcing\n",
363 		    com->c_name);
364 		goto out;
365 	}
366 	if (readonly && com->c_argtype & W) {
367 		printf("May not execute \"%s\" -- message file is read only\n",
368 		   com->c_name);
369 		goto out;
370 	}
371 	if (contxt && com->c_argtype & R) {
372 		printf("Cannot recursively invoke \"%s\"\n", com->c_name);
373 		goto out;
374 	}
375 	switch (com->c_argtype & ~(F|P|I|M|T|W|R)) {
376 	case MSGLIST:
377 		/*
378 		 * A message list defaulting to nearest forward
379 		 * legal message.
380 		 */
381 		if (msgvec == 0) {
382 			printf("Illegal use of \"message list\"\n");
383 			break;
384 		}
385 		if ((c = getmsglist(cp, msgvec, com->c_msgflag)) < 0)
386 			break;
387 		if (c  == 0) {
388 			*msgvec = first(com->c_msgflag,
389 				com->c_msgmask);
390 			msgvec[1] = 0;
391 		}
392 		if (*msgvec == 0) {
393 			printf("No applicable messages\n");
394 			break;
395 		}
396 		e = (*com->c_func)(msgvec);
397 		break;
398 
399 	case NDMLIST:
400 		/*
401 		 * A message list with no defaults, but no error
402 		 * if none exist.
403 		 */
404 		if (msgvec == 0) {
405 			printf("Illegal use of \"message list\"\n");
406 			break;
407 		}
408 		if (getmsglist(cp, msgvec, com->c_msgflag) < 0)
409 			break;
410 		e = (*com->c_func)(msgvec);
411 		break;
412 
413 	case STRLIST:
414 		/*
415 		 * Just the straight string, with
416 		 * leading blanks removed.
417 		 */
418 		while (isspace((unsigned char)*cp))
419 			cp++;
420 		e = (*com->c_func)(cp);
421 		break;
422 
423 	case RAWLIST:
424 		/*
425 		 * A vector of strings, in shell style.
426 		 */
427 		if ((c = getrawlist(cp, arglist,
428 				sizeof arglist / sizeof *arglist)) < 0)
429 			break;
430 		if (c < com->c_minargs) {
431 			printf("%s requires at least %d arg(s)\n",
432 				com->c_name, com->c_minargs);
433 			break;
434 		}
435 		if (c > com->c_maxargs) {
436 			printf("%s takes no more than %d arg(s)\n",
437 				com->c_name, com->c_maxargs);
438 			break;
439 		}
440 		e = (*com->c_func)(arglist);
441 		break;
442 
443 	case NOLIST:
444 		/*
445 		 * Just the constant zero, for exiting,
446 		 * eg.
447 		 */
448 		e = (*com->c_func)(0);
449 		break;
450 
451 	default:
452 		errx(1, "Unknown argtype");
453 	}
454 
455 out:
456 	/*
457 	 * Exit the current source file on
458 	 * error.
459 	 */
460 	if (e) {
461 		if (e < 0)
462 			return 1;
463 		if (loading)
464 			return 1;
465 		if (sourcing)
466 			unstack();
467 		return 0;
468 	}
469 	if (com == NULL)
470 		return(0);
471 	if (value("autoprint") != NOSTR && com->c_argtype & P)
472 		if ((dot->m_flag & MDELETED) == 0) {
473 			muvec[0] = dot - &message[0] + 1;
474 			muvec[1] = 0;
475 			type(muvec);
476 		}
477 	if (!sourcing && (com->c_argtype & T) == 0)
478 		sawcom = 1;
479 	return(0);
480 }
481 
482 /*
483  * Set the size of the message vector used to construct argument
484  * lists to message list functions.
485  */
486 void
487 setmsize(sz)
488 	int sz;
489 {
490 
491 	if (msgvec != 0)
492 		free((char *) msgvec);
493 	msgvec = (int *) calloc((unsigned) (sz + 1), sizeof *msgvec);
494 }
495 
496 /*
497  * Find the correct command in the command table corresponding
498  * to the passed command "word"
499  */
500 
501 const struct cmd *
502 lex(word)
503 	char word[];
504 {
505 	extern const struct cmd cmdtab[];
506 	const struct cmd *cp;
507 
508 	for (cp = &cmdtab[0]; cp->c_name != NOSTR; cp++)
509 		if (isprefix(word, cp->c_name))
510 			return(cp);
511 	return(NONE);
512 }
513 
514 /*
515  * Determine if as1 is a valid prefix of as2.
516  * Return true if yep.
517  */
518 int
519 isprefix(as1, as2)
520 	char *as1, *as2;
521 {
522 	char *s1, *s2;
523 
524 	s1 = as1;
525 	s2 = as2;
526 	while (*s1++ == *s2)
527 		if (*s2++ == '\0')
528 			return(1);
529 	return(*--s1 == '\0');
530 }
531 
532 /*
533  * The following gets called on receipt of an interrupt.  This is
534  * to abort printout of a command, mainly.
535  * Dispatching here when command() is inactive crashes rcv.
536  * Close all open files except 0, 1, 2, and the temporary.
537  * Also, unstack all source files.
538  */
539 
540 int	inithdr;			/* am printing startup headers */
541 
542 /*ARGSUSED*/
543 void
544 intr(s)
545 	int s;
546 {
547 
548 	noreset = 0;
549 	if (!inithdr)
550 		sawcom++;
551 	inithdr = 0;
552 	while (sourcing)
553 		unstack();
554 
555 	close_all_files();
556 
557 	if (image >= 0) {
558 		close(image);
559 		image = -1;
560 	}
561 	fprintf(stderr, "Interrupt\n");
562 	reset(0);
563 }
564 
565 /*
566  * When we wake up after ^Z, reprint the prompt.
567  */
568 void
569 stop(s)
570 	int s;
571 {
572 	sig_t old_action = signal(s, SIG_DFL);
573 	sigset_t nset;
574 
575 	sigemptyset(&nset);
576 	sigaddset(&nset, s);
577 	sigprocmask(SIG_UNBLOCK, &nset, NULL);
578 	kill(0, s);
579 	sigprocmask(SIG_BLOCK, &nset, NULL);
580 	signal(s, old_action);
581 	if (reset_on_stop) {
582 		reset_on_stop = 0;
583 		reset(0);
584 	}
585 }
586 
587 /*
588  * Branch here on hangup signal and simulate "exit".
589  */
590 /*ARGSUSED*/
591 void
592 hangup(s)
593 	int s;
594 {
595 
596 	/* nothing to do? */
597 	exit(1);
598 }
599 
600 /*
601  * Announce the presence of the current Mail version,
602  * give the message count, and print a header listing.
603  */
604 void
605 announce()
606 {
607 	int vec[2], mdot;
608 
609 	mdot = newfileinfo(0);
610 	vec[0] = mdot;
611 	vec[1] = 0;
612 	dot = &message[mdot - 1];
613 	if (msgCount > 0 && value("noheader") == NOSTR) {
614 		inithdr++;
615 		headers(vec);
616 		inithdr = 0;
617 	}
618 }
619 
620 /*
621  * Announce information about the file we are editing.
622  * Return a likely place to set dot.
623  */
624 int
625 newfileinfo(omsgCount)
626 	int omsgCount;
627 {
628 	struct message *mp;
629 	int u, n, mdot, d, s, l;
630 	char fname[PATHSIZE], zname[PATHSIZE], *ename;
631 
632 	for (mp = &message[omsgCount]; mp < &message[msgCount]; mp++)
633 		if (mp->m_flag & MNEW)
634 			break;
635 	if (mp >= &message[msgCount])
636 		for (mp = &message[omsgCount]; mp < &message[msgCount]; mp++)
637 			if ((mp->m_flag & MREAD) == 0)
638 				break;
639 	if (mp < &message[msgCount])
640 		mdot = mp - &message[0] + 1;
641 	else
642 		mdot = omsgCount + 1;
643 	s = d = 0;
644 	for (mp = &message[0], n = 0, u = 0; mp < &message[msgCount]; mp++) {
645 		if (mp->m_flag & MNEW)
646 			n++;
647 		if ((mp->m_flag & MREAD) == 0)
648 			u++;
649 		if (mp->m_flag & MDELETED)
650 			d++;
651 		if (mp->m_flag & MSAVED)
652 			s++;
653 	}
654 	ename = mailname;
655 	if (getfold(fname) >= 0) {
656 		l = strlen(fname);
657 		if (l < PATHSIZE - 1)
658 			fname[l++] = '/';
659 		if (strncmp(fname, mailname, l) == 0) {
660 			snprintf(zname, PATHSIZE, "+%s",
661 			    mailname + l);
662 			ename = zname;
663 		}
664 	}
665 	printf("\"%s\": ", ename);
666 	if (msgCount == 1)
667 		printf("1 message");
668 	else
669 		printf("%d messages", msgCount);
670 	if (n > 0)
671 		printf(" %d new", n);
672 	if (u-n > 0)
673 		printf(" %d unread", u);
674 	if (d > 0)
675 		printf(" %d deleted", d);
676 	if (s > 0)
677 		printf(" %d saved", s);
678 	if (readonly)
679 		printf(" [Read only]");
680 	printf("\n");
681 	return(mdot);
682 }
683 
684 /*
685  * Print the current version number.
686  */
687 
688 /*ARGSUSED*/
689 int
690 pversion(v)
691 	void *v;
692 {
693 	extern char *version;
694 
695 	printf("Version %s\n", version);
696 	return(0);
697 }
698 
699 /*
700  * Load a file of user definitions.
701  */
702 void
703 load(name)
704 	char *name;
705 {
706 	FILE *in, *oldin;
707 
708 	if ((in = Fopen(name, "r")) == NULL)
709 		return;
710 	oldin = input;
711 	input = in;
712 	loading = 1;
713 	sourcing = 1;
714 	commands();
715 	loading = 0;
716 	sourcing = 0;
717 	input = oldin;
718 	Fclose(in);
719 }
720