xref: /netbsd-src/usr.bin/mail/lex.c (revision 23c8222edbfb0f0932d88a8351d3a0cf817dfb9e)
1 /*	$NetBSD: lex.c,v 1.23 2003/08/07 11:14:39 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[] = "@(#)lex.c	8.2 (Berkeley) 4/20/95";
36 #else
37 __RCSID("$NetBSD: lex.c,v 1.23 2003/08/07 11:14:39 agc Exp $");
38 #endif
39 #endif /* not lint */
40 
41 #include "rcv.h"
42 #include "extern.h"
43 
44 /*
45  * Mail -- a mail program
46  *
47  * Lexical processing of commands.
48  */
49 
50 extern char *tmpdir;
51 extern char *version;
52 extern const struct cmd cmdtab[];
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(char *name)
64 {
65 	FILE *ibuf;
66 	int i, fd;
67 	struct stat stb;
68 	char isedit = *name != '%' || getuserid(myname) != getuid();
69 	char *who = name[1] ? name + 1 : myname;
70 	static int shudclob;
71 	char tempname[PATHSIZE];
72 
73 	if ((name = expand(name)) == NULL)
74 		return -1;
75 
76 	if ((ibuf = Fopen(name, "r")) == NULL) {
77 		if (!isedit && errno == ENOENT)
78 			goto nomail;
79 		warn("%s", name);
80 		return(-1);
81 	}
82 
83 	if (fstat(fileno(ibuf), &stb) < 0) {
84 		warn("fstat");
85 		Fclose(ibuf);
86 		return (-1);
87 	}
88 
89 	switch (stb.st_mode & S_IFMT) {
90 	case S_IFDIR:
91 		Fclose(ibuf);
92 		errno = EISDIR;
93 		warn("%s", name);
94 		return (-1);
95 
96 	case S_IFREG:
97 		break;
98 
99 	default:
100 		Fclose(ibuf);
101 		errno = EINVAL;
102 		warn("%s", name);
103 		return (-1);
104 	}
105 
106 	/*
107 	 * Looks like all will be well.  We must now relinquish our
108 	 * hold on the current set of stuff.  Must hold signals
109 	 * while we are reading the new file, else we will ruin
110 	 * the message[] data structure.
111 	 */
112 
113 	holdsigs();
114 	if (shudclob)
115 		quit();
116 
117 	/*
118 	 * Copy the messages into /tmp
119 	 * and set pointers.
120 	 */
121 
122 	readonly = 0;
123 	if ((i = open(name, 1)) < 0)
124 		readonly++;
125 	else
126 		close(i);
127 	if (shudclob) {
128 		fclose(itf);
129 		fclose(otf);
130 	}
131 	shudclob = 1;
132 	edit = isedit;
133 	strcpy(prevfile, mailname);
134 	if (name != mailname)
135 		strcpy(mailname, name);
136 	mailsize = fsize(ibuf);
137 	(void)snprintf(tempname, sizeof(tempname),
138 	    "%s/mail.RxXXXXXXXXXX", tmpdir);
139 	if ((fd = mkstemp(tempname)) == -1 ||
140 	    (otf = fdopen(fd, "w")) == NULL)
141 		err(1, "%s", tempname);
142 	(void)fcntl(fileno(otf), F_SETFD, 1);
143 	if ((itf = fopen(tempname, "r")) == NULL)
144 		err(1, "%s", tempname);
145 	(void)fcntl(fileno(itf), F_SETFD, 1);
146 	rm(tempname);
147 	setptr(ibuf, 0);
148 	setmsize(msgCount);
149 	/*
150 	 * New mail may have arrived while we were reading
151 	 * the mail file, so reset mailsize to be where
152 	 * we really are in the file...
153 	 */
154 	mailsize = ftell(ibuf);
155 	Fclose(ibuf);
156 	relsesigs();
157 	sawcom = 0;
158 	if (!edit && msgCount == 0) {
159 nomail:
160 		fprintf(stderr, "No mail for %s\n", who);
161 		return -1;
162 	}
163 	return(0);
164 }
165 
166 /*
167  * Incorporate any new mail that has arrived since we first
168  * started reading mail.
169  */
170 int
171 incfile(void)
172 {
173 	int newsize;
174 	int omsgCount = msgCount;
175 	FILE *ibuf;
176 
177 	ibuf = Fopen(mailname, "r");
178 	if (ibuf == NULL)
179 		return -1;
180 	holdsigs();
181 	newsize = fsize(ibuf);
182 	if (newsize == 0)
183 		return -1;		/* mail box is now empty??? */
184 	if (newsize < mailsize)
185 		return -1;              /* mail box has shrunk??? */
186 	if (newsize == mailsize)
187 		return 0;               /* no new mail */
188 	setptr(ibuf, mailsize);
189 	setmsize(msgCount);
190 	mailsize = ftell(ibuf);
191 	Fclose(ibuf);
192 	relsesigs();
193 	return(msgCount - omsgCount);
194 }
195 
196 int	*msgvec;
197 int	reset_on_stop;			/* do a reset() if stopped */
198 
199 /*
200  * Interpret user commands one by one.  If standard input is not a tty,
201  * print no prompt.
202  */
203 void
204 commands(void)
205 {
206 	int eofloop = 0;
207 	int n;
208 	char linebuf[LINESIZE];
209 #if __GNUC__
210 	/* Avoid longjmp clobbering */
211 	(void)&eofloop;
212 #endif
213 
214 	if (!sourcing) {
215 		if (signal(SIGINT, SIG_IGN) != SIG_IGN)
216 			signal(SIGINT, intr);
217 		if (signal(SIGHUP, SIG_IGN) != SIG_IGN)
218 			signal(SIGHUP, hangup);
219 		signal(SIGTSTP, stop);
220 		signal(SIGTTOU, stop);
221 		signal(SIGTTIN, stop);
222 	}
223 	setexit();
224 	for (;;) {
225 		/*
226 		 * Print the prompt, if needed.  Clear out
227 		 * string space, and flush the output.
228 		 */
229 		if (!sourcing && value("interactive") != NULL) {
230 			if ((value("autoinc") != NULL) && (incfile() > 0))
231 				printf("New mail has arrived.\n");
232 			reset_on_stop = 1;
233 			printf("%s", prompt);
234 		}
235 		fflush(stdout);
236 		sreset();
237 		/*
238 		 * Read a line of commands from the current input
239 		 * and handle end of file specially.
240 		 */
241 		n = 0;
242 		for (;;) {
243 			if (readline(input, &linebuf[n], LINESIZE - n) < 0) {
244 				if (n == 0)
245 					n = -1;
246 				break;
247 			}
248 			if ((n = strlen(linebuf)) == 0)
249 				break;
250 			n--;
251 			if (linebuf[n] != '\\')
252 				break;
253 			linebuf[n++] = ' ';
254 		}
255 		reset_on_stop = 0;
256 		if (n < 0) {
257 				/* eof */
258 			if (loading)
259 				break;
260 			if (sourcing) {
261 				unstack();
262 				continue;
263 			}
264 			if (value("interactive") != NULL &&
265 			    value("ignoreeof") != NULL &&
266 			    ++eofloop < 25) {
267 				printf("Use \"quit\" to quit.\n");
268 				continue;
269 			}
270 			break;
271 		}
272 		eofloop = 0;
273 		if (execute(linebuf, 0))
274 			break;
275 	}
276 }
277 
278 /*
279  * Execute a single command.
280  * Command functions return 0 for success, 1 for error, and -1
281  * for abort.  A 1 or -1 aborts a load or source.  A -1 aborts
282  * the interactive command loop.
283  * Contxt is non-zero if called while composing mail.
284  */
285 int
286 execute(char linebuf[], int contxt)
287 {
288 	char word[LINESIZE];
289 	char *arglist[MAXARGC];
290 	const struct cmd *com = NULL;
291 	char *cp, *cp2;
292 	int c;
293 	int muvec[2];
294 	int e = 1;
295 
296 	/*
297 	 * Strip the white space away from the beginning
298 	 * of the command, then scan out a word, which
299 	 * consists of anything except digits and white space.
300 	 *
301 	 * Handle ! escapes differently to get the correct
302 	 * lexical conventions.
303 	 */
304 
305 	for (cp = linebuf; isspace((unsigned char)*cp); cp++)
306 		;
307 	if (*cp == '!') {
308 		if (sourcing) {
309 			printf("Can't \"!\" while sourcing\n");
310 			goto out;
311 		}
312 		shell(cp+1);
313 		return(0);
314 	}
315 	cp2 = word;
316 	while (*cp && strchr(" \t0123456789$^.:/-+*'\"", *cp) == NULL)
317 		*cp2++ = *cp++;
318 	*cp2 = '\0';
319 
320 	/*
321 	 * Look up the command; if not found, bitch.
322 	 * Normally, a blank command would map to the
323 	 * first command in the table; while sourcing,
324 	 * however, we ignore blank lines to eliminate
325 	 * confusion.
326 	 */
327 
328 	if (sourcing && *word == '\0')
329 		return(0);
330 	com = lex(word);
331 	if (com == NULL) {
332 		printf("Unknown command: \"%s\"\n", word);
333 		goto out;
334 	}
335 
336 	/*
337 	 * See if we should execute the command -- if a conditional
338 	 * we always execute it, otherwise, check the state of cond.
339 	 */
340 
341 	if ((com->c_argtype & F) == 0)
342 		if ((cond == CRCV && !rcvmode) || (cond == CSEND && rcvmode))
343 			return(0);
344 
345 	/*
346 	 * Process the arguments to the command, depending
347 	 * on the type he expects.  Default to an error.
348 	 * If we are sourcing an interactive command, it's
349 	 * an error.
350 	 */
351 
352 	if (!rcvmode && (com->c_argtype & M) == 0) {
353 		printf("May not execute \"%s\" while sending\n",
354 		    com->c_name);
355 		goto out;
356 	}
357 	if (sourcing && com->c_argtype & I) {
358 		printf("May not execute \"%s\" while sourcing\n",
359 		    com->c_name);
360 		goto out;
361 	}
362 	if (readonly && com->c_argtype & W) {
363 		printf("May not execute \"%s\" -- message file is read only\n",
364 		   com->c_name);
365 		goto out;
366 	}
367 	if (contxt && com->c_argtype & R) {
368 		printf("Cannot recursively invoke \"%s\"\n", com->c_name);
369 		goto out;
370 	}
371 	switch (com->c_argtype & ~(F|P|I|M|T|W|R)) {
372 	case MSGLIST:
373 		/*
374 		 * A message list defaulting to nearest forward
375 		 * legal message.
376 		 */
377 		if (msgvec == 0) {
378 			printf("Illegal use of \"message list\"\n");
379 			break;
380 		}
381 		if ((c = getmsglist(cp, msgvec, com->c_msgflag)) < 0)
382 			break;
383 		if (c  == 0) {
384 			*msgvec = first(com->c_msgflag,
385 				com->c_msgmask);
386 			msgvec[1] = 0;
387 		}
388 		if (*msgvec == 0) {
389 			printf("No applicable messages\n");
390 			break;
391 		}
392 		e = (*com->c_func)(msgvec);
393 		break;
394 
395 	case NDMLIST:
396 		/*
397 		 * A message list with no defaults, but no error
398 		 * if none exist.
399 		 */
400 		if (msgvec == 0) {
401 			printf("Illegal use of \"message list\"\n");
402 			break;
403 		}
404 		if (getmsglist(cp, msgvec, com->c_msgflag) < 0)
405 			break;
406 		e = (*com->c_func)(msgvec);
407 		break;
408 
409 	case STRLIST:
410 		/*
411 		 * Just the straight string, with
412 		 * leading blanks removed.
413 		 */
414 		while (isspace((unsigned char)*cp))
415 			cp++;
416 		e = (*com->c_func)(cp);
417 		break;
418 
419 	case RAWLIST:
420 		/*
421 		 * A vector of strings, in shell style.
422 		 */
423 		if ((c = getrawlist(cp, arglist,
424 				sizeof arglist / sizeof *arglist)) < 0)
425 			break;
426 		if (c < com->c_minargs) {
427 			printf("%s requires at least %d arg(s)\n",
428 				com->c_name, com->c_minargs);
429 			break;
430 		}
431 		if (c > com->c_maxargs) {
432 			printf("%s takes no more than %d arg(s)\n",
433 				com->c_name, com->c_maxargs);
434 			break;
435 		}
436 		e = (*com->c_func)(arglist);
437 		break;
438 
439 	case NOLIST:
440 		/*
441 		 * Just the constant zero, for exiting,
442 		 * eg.
443 		 */
444 		e = (*com->c_func)(0);
445 		break;
446 
447 	default:
448 		errx(1, "Unknown argtype");
449 	}
450 
451 out:
452 	/*
453 	 * Exit the current source file on
454 	 * error.
455 	 */
456 	if (e) {
457 		if (e < 0)
458 			return 1;
459 		if (loading)
460 			return 1;
461 		if (sourcing)
462 			unstack();
463 		return 0;
464 	}
465 	if (com == NULL)
466 		return(0);
467 	if (value("autoprint") != NULL && com->c_argtype & P)
468 		if ((dot->m_flag & MDELETED) == 0) {
469 			muvec[0] = dot - &message[0] + 1;
470 			muvec[1] = 0;
471 			type(muvec);
472 		}
473 	if (!sourcing && (com->c_argtype & T) == 0)
474 		sawcom = 1;
475 	return(0);
476 }
477 
478 /*
479  * Set the size of the message vector used to construct argument
480  * lists to message list functions.
481  */
482 void
483 setmsize(int sz)
484 {
485 
486 	if (msgvec != 0)
487 		free((char *) msgvec);
488 	msgvec = (int *) calloc((unsigned) (sz + 1), sizeof *msgvec);
489 }
490 
491 /*
492  * Find the correct command in the command table corresponding
493  * to the passed command "word"
494  */
495 
496 const struct cmd *
497 lex(char word[])
498 {
499 	const struct cmd *cp;
500 
501 	for (cp = &cmdtab[0]; cp->c_name != NULL; cp++)
502 		if (isprefix(word, cp->c_name))
503 			return(cp);
504 	return(NULL);
505 }
506 
507 /*
508  * Determine if as1 is a valid prefix of as2.
509  * Return true if yep.
510  */
511 int
512 isprefix(char *as1, char *as2)
513 {
514 	char *s1, *s2;
515 
516 	s1 = as1;
517 	s2 = as2;
518 	while (*s1++ == *s2)
519 		if (*s2++ == '\0')
520 			return(1);
521 	return(*--s1 == '\0');
522 }
523 
524 /*
525  * The following gets called on receipt of an interrupt.  This is
526  * to abort printout of a command, mainly.
527  * Dispatching here when command() is inactive crashes rcv.
528  * Close all open files except 0, 1, 2, and the temporary.
529  * Also, unstack all source files.
530  */
531 
532 int	inithdr;			/* am printing startup headers */
533 
534 /*ARGSUSED*/
535 void
536 intr(int s)
537 {
538 
539 	noreset = 0;
540 	if (!inithdr)
541 		sawcom++;
542 	inithdr = 0;
543 	while (sourcing)
544 		unstack();
545 
546 	close_all_files();
547 
548 	if (image >= 0) {
549 		close(image);
550 		image = -1;
551 	}
552 	fprintf(stderr, "Interrupt\n");
553 	reset(0);
554 }
555 
556 /*
557  * When we wake up after ^Z, reprint the prompt.
558  */
559 void
560 stop(int s)
561 {
562 	sig_t old_action = signal(s, SIG_DFL);
563 	sigset_t nset;
564 
565 	sigemptyset(&nset);
566 	sigaddset(&nset, s);
567 	sigprocmask(SIG_UNBLOCK, &nset, NULL);
568 	kill(0, s);
569 	sigprocmask(SIG_BLOCK, &nset, NULL);
570 	signal(s, old_action);
571 	if (reset_on_stop) {
572 		reset_on_stop = 0;
573 		reset(0);
574 	}
575 }
576 
577 /*
578  * Branch here on hangup signal and simulate "exit".
579  */
580 /*ARGSUSED*/
581 void
582 hangup(int s)
583 {
584 
585 	/* nothing to do? */
586 	exit(1);
587 }
588 
589 /*
590  * Announce the presence of the current Mail version,
591  * give the message count, and print a header listing.
592  */
593 void
594 announce(void)
595 {
596 	int vec[2], mdot;
597 
598 	mdot = newfileinfo(0);
599 	vec[0] = mdot;
600 	vec[1] = 0;
601 	dot = &message[mdot - 1];
602 	if (msgCount > 0 && value("noheader") == NULL) {
603 		inithdr++;
604 		headers(vec);
605 		inithdr = 0;
606 	}
607 }
608 
609 /*
610  * Announce information about the file we are editing.
611  * Return a likely place to set dot.
612  */
613 int
614 newfileinfo(int omsgCount)
615 {
616 	struct message *mp;
617 	int u, n, mdot, d, s, l;
618 	char fname[PATHSIZE], zname[PATHSIZE], *ename;
619 
620 	for (mp = &message[omsgCount]; mp < &message[msgCount]; mp++)
621 		if (mp->m_flag & MNEW)
622 			break;
623 	if (mp >= &message[msgCount])
624 		for (mp = &message[omsgCount]; mp < &message[msgCount]; mp++)
625 			if ((mp->m_flag & MREAD) == 0)
626 				break;
627 	if (mp < &message[msgCount])
628 		mdot = mp - &message[0] + 1;
629 	else
630 		mdot = omsgCount + 1;
631 	s = d = 0;
632 	for (mp = &message[0], n = 0, u = 0; mp < &message[msgCount]; mp++) {
633 		if (mp->m_flag & MNEW)
634 			n++;
635 		if ((mp->m_flag & MREAD) == 0)
636 			u++;
637 		if (mp->m_flag & MDELETED)
638 			d++;
639 		if (mp->m_flag & MSAVED)
640 			s++;
641 	}
642 	ename = mailname;
643 	if (getfold(fname) >= 0) {
644 		l = strlen(fname);
645 		if (l < PATHSIZE - 1)
646 			fname[l++] = '/';
647 		if (strncmp(fname, mailname, l) == 0) {
648 			snprintf(zname, PATHSIZE, "+%s",
649 			    mailname + l);
650 			ename = zname;
651 		}
652 	}
653 	printf("\"%s\": ", ename);
654 	if (msgCount == 1)
655 		printf("1 message");
656 	else
657 		printf("%d messages", msgCount);
658 	if (n > 0)
659 		printf(" %d new", n);
660 	if (u-n > 0)
661 		printf(" %d unread", u);
662 	if (d > 0)
663 		printf(" %d deleted", d);
664 	if (s > 0)
665 		printf(" %d saved", s);
666 	if (readonly)
667 		printf(" [Read only]");
668 	printf("\n");
669 	return(mdot);
670 }
671 
672 /*
673  * Print the current version number.
674  */
675 
676 /*ARGSUSED*/
677 int
678 pversion(void *v)
679 {
680 	printf("Version %s\n", version);
681 	return(0);
682 }
683 
684 /*
685  * Load a file of user definitions.
686  */
687 void
688 load(char *name)
689 {
690 	FILE *in, *oldin;
691 
692 	if ((in = Fopen(name, "r")) == NULL)
693 		return;
694 	oldin = input;
695 	input = in;
696 	loading = 1;
697 	sourcing = 1;
698 	commands();
699 	loading = 0;
700 	sourcing = 0;
701 	input = oldin;
702 	Fclose(in);
703 }
704