xref: /netbsd-src/usr.bin/mail/lex.c (revision ce2c90c7c172d95d2402a5b3d96d8f8e6d138a21)
1 /*	$NetBSD: lex.c,v 1.27 2006/09/29 14:59:31 christos 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 1.27 2006/09/29 14:59:31 christos Exp $");
38 #endif
39 #endif /* not lint */
40 
41 #include "rcv.h"
42 #include "extern.h"
43 
44 #ifdef USE_READLINE
45 #include "complete.h"
46 #endif
47 
48 /*
49  * Mail -- a mail program
50  *
51  * Lexical processing of commands.
52  */
53 
54 const 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(const char *name)
64 {
65 	FILE *ibuf;
66 	int i, fd;
67 	struct stat stb;
68 	char isedit = *name != '%' || getuserid(myname) != getuid();
69 	const 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 		(void)Fclose(ibuf);
86 		return (-1);
87 	}
88 
89 	switch (stb.st_mode & S_IFMT) {
90 	case S_IFDIR:
91 		(void)Fclose(ibuf);
92 		errno = EISDIR;
93 		warn("%s", name);
94 		return (-1);
95 
96 	case S_IFREG:
97 		break;
98 
99 	default:
100 		(void)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 		(void)close(i);
127 	if (shudclob) {
128 		(void)fclose(itf);
129 		(void)fclose(otf);
130 	}
131 	shudclob = 1;
132 	edit = isedit;
133 	(void)strcpy(prevfile, mailname);
134 	if (name != mailname)
135 		(void)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 	(void)rm(tempname);
147 	setptr(ibuf, (off_t)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 	(void)Fclose(ibuf);
156 	relsesigs();
157 	sawcom = 0;
158 	if (!edit && msgCount == 0) {
159 nomail:
160 		(void)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 	off_t 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 	(void)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 n;
207 	char linebuf[LINESIZE];
208 	volatile int eofloop = 0;	/* avoid longjmp clobbering */
209 
210 	if (!sourcing) {
211 		if (signal(SIGINT, SIG_IGN) != SIG_IGN)
212 			(void)signal(SIGINT, intr);
213 		if (signal(SIGHUP, SIG_IGN) != SIG_IGN)
214 			(void)signal(SIGHUP, hangup);
215 		(void)signal(SIGTSTP, stop);
216 		(void)signal(SIGTTOU, stop);
217 		(void)signal(SIGTTIN, stop);
218 	}
219 	setexit();	/* defined as (void)setjmp(srbuf) in def.h */
220 	for (;;) {
221 		/*
222 		 * Print the prompt, if needed.  Clear out
223 		 * string space, and flush the output.
224 		 */
225 		if (!sourcing && value("interactive") != NULL) {
226 			if ((value("autoinc") != NULL) && (incfile() > 0))
227 				(void)printf("New mail has arrived.\n");
228 			reset_on_stop = 1;
229 #ifndef USE_READLINE
230 			(void)printf("%s", prompt);
231 #endif
232 		}
233 		(void)fflush(stdout);
234 		sreset();
235 		/*
236 		 * Read a line of commands from the current input
237 		 * and handle end of file specially.
238 		 */
239 		n = 0;
240 		for (;;) {
241 #ifdef USE_READLINE
242 			if (!sourcing) {
243 				char *line;
244 
245 				if ((line = rl_gets(prompt)) == NULL) {
246 					if (n == 0)
247 						n = -1;
248 					break;
249 				}
250 				strncpy(linebuf, line, LINESIZE);
251 			}
252 			else {
253 				if (readline(input, &linebuf[n], LINESIZE - n) < 0) {
254 					if (n == 0)
255 						n = -1;
256 					break;
257 				}
258 			}
259 #else /* USE_READLINE */
260 			if (readline(input, &linebuf[n], LINESIZE - n) < 0) {
261 				if (n == 0)
262 					n = -1;
263 				break;
264 			}
265 #endif /* USE_READLINE */
266 
267 			if (sourcing) {  /* allow comments in source files */
268 				char *ptr = strchr(linebuf, '#');
269 				if (ptr)
270 					*ptr = '\0';
271 			}
272 			if ((n = strlen(linebuf)) == 0)
273 				break;
274 			n--;
275 			if (linebuf[n] != '\\')
276 				break;
277 			linebuf[n++] = ' ';
278 		}
279 		reset_on_stop = 0;
280 		if (n < 0) {
281 				/* eof */
282 			if (loading)
283 				break;
284 			if (sourcing) {
285 				(void)unstack();
286 				continue;
287 			}
288 #ifdef USE_READLINE
289 			{
290 				char *p;
291 				if (value("interactive") != NULL &&
292 				    (p=value("ignoreeof")) != NULL &&
293 				    ++eofloop < (*p==0 ? 25 : atoi(p))) {
294 					(void)printf("Use \"quit\" to quit.\n");
295 					continue;
296 				}
297 			}
298 #else
299 			if (value("interactive") != NULL &&
300 			    value("ignoreeof") != NULL &&
301 			    ++eofloop < 25) {
302 				(void)printf("Use \"quit\" to quit.\n");
303 				continue;
304 			}
305 #endif
306 			break;
307 		}
308 		eofloop = 0;
309 		if (execute(linebuf, 0))
310 			break;
311 	}
312 }
313 
314 /*
315  * Execute a single command.
316  * Command functions return 0 for success, 1 for error, and -1
317  * for abort.  A 1 or -1 aborts a load or source.  A -1 aborts
318  * the interactive command loop.
319  * Contxt is non-zero if called while composing mail.
320  */
321 int
322 execute(char linebuf[], int contxt)
323 {
324 	char word[LINESIZE];
325 	char *arglist[MAXARGC];
326 	const struct cmd *com = NULL;
327 	char *cp, *cp2;
328 	int c;
329 	int muvec[2];
330 	int e = 1;
331 
332 	/*
333 	 * Strip the white space away from the beginning
334 	 * of the command, then scan out a word, which
335 	 * consists of anything except digits and white space.
336 	 *
337 	 * Handle ! escapes differently to get the correct
338 	 * lexical conventions.
339 	 */
340 
341 	for (cp = linebuf; isspace((unsigned char)*cp); cp++)
342 		;
343 	if (*cp == '!') {
344 		if (sourcing) {
345 			(void)printf("Can't \"!\" while sourcing\n");
346 			goto out;
347 		}
348 		(void)shell(cp+1);
349 		return(0);
350 	}
351 	cp2 = word;
352 	while (*cp && strchr(" \t0123456789$^.:/-+*'\"", *cp) == NULL)
353 		*cp2++ = *cp++;
354 	*cp2 = '\0';
355 
356 	/*
357 	 * Look up the command; if not found, bitch.
358 	 * Normally, a blank command would map to the
359 	 * first command in the table; while sourcing,
360 	 * however, we ignore blank lines to eliminate
361 	 * confusion.
362 	 */
363 
364 	if (sourcing && *word == '\0')
365 		return(0);
366 	com = lex(word);
367 	if (com == NULL) {
368 		(void)printf("Unknown command: \"%s\"\n", word);
369 		goto out;
370 	}
371 
372 	/*
373 	 * See if we should execute the command -- if a conditional
374 	 * we always execute it, otherwise, check the state of cond.
375 	 */
376 
377 	if ((com->c_argtype & F) == 0)
378 		if ((cond == CRCV && !rcvmode) || (cond == CSEND && rcvmode))
379 			return(0);
380 
381 	/*
382 	 * Process the arguments to the command, depending
383 	 * on the type he expects.  Default to an error.
384 	 * If we are sourcing an interactive command, it's
385 	 * an error.
386 	 */
387 
388 	if (!rcvmode && (com->c_argtype & M) == 0) {
389 		(void)printf("May not execute \"%s\" while sending\n",
390 		    com->c_name);
391 		goto out;
392 	}
393 	if (sourcing && com->c_argtype & I) {
394 		(void)printf("May not execute \"%s\" while sourcing\n",
395 		    com->c_name);
396 		goto out;
397 	}
398 	if (readonly && com->c_argtype & W) {
399 		(void)printf("May not execute \"%s\" -- message file is read only\n",
400 		   com->c_name);
401 		goto out;
402 	}
403 	if (contxt && com->c_argtype & R) {
404 		(void)printf("Cannot recursively invoke \"%s\"\n", com->c_name);
405 		goto out;
406 	}
407 	switch (com->c_argtype & ~(F|P|I|M|T|W|R)) {
408 	case MSGLIST:
409 		/*
410 		 * A message list defaulting to nearest forward
411 		 * legal message.
412 		 */
413 		if (msgvec == 0) {
414 			(void)printf("Illegal use of \"message list\"\n");
415 			break;
416 		}
417 		if ((c = getmsglist(cp, msgvec, com->c_msgflag)) < 0)
418 			break;
419 		if (c  == 0) {
420 			*msgvec = first(com->c_msgflag,
421 				com->c_msgmask);
422 			msgvec[1] = 0;
423 		}
424 		if (*msgvec == 0) {
425 			(void)printf("No applicable messages\n");
426 			break;
427 		}
428 		e = (*com->c_func)(msgvec);
429 		break;
430 
431 	case NDMLIST:
432 		/*
433 		 * A message list with no defaults, but no error
434 		 * if none exist.
435 		 */
436 		if (msgvec == 0) {
437 			(void)printf("Illegal use of \"message list\"\n");
438 			break;
439 		}
440 		if (getmsglist(cp, msgvec, com->c_msgflag) < 0)
441 			break;
442 		e = (*com->c_func)(msgvec);
443 		break;
444 
445 	case STRLIST:
446 		/*
447 		 * Just the straight string, with
448 		 * leading blanks removed.
449 		 */
450 		while (isspace((unsigned char)*cp))
451 			cp++;
452 		e = (*com->c_func)(cp);
453 		break;
454 
455 	case RAWLIST:
456 		/*
457 		 * A vector of strings, in shell style.
458 		 */
459 		if ((c = getrawlist(cp, arglist,
460 				sizeof arglist / sizeof *arglist)) < 0)
461 			break;
462 		if (c < com->c_minargs) {
463 			(void)printf("%s requires at least %d arg(s)\n",
464 				com->c_name, com->c_minargs);
465 			break;
466 		}
467 		if (c > com->c_maxargs) {
468 			(void)printf("%s takes no more than %d arg(s)\n",
469 				com->c_name, com->c_maxargs);
470 			break;
471 		}
472 		e = (*com->c_func)(arglist);
473 		break;
474 
475 	case NOLIST:
476 		/*
477 		 * Just the constant zero, for exiting,
478 		 * eg.
479 		 */
480 		e = (*com->c_func)(0);
481 		break;
482 
483 	default:
484 		errx(1, "Unknown argtype");
485 	}
486 
487 out:
488 	/*
489 	 * Exit the current source file on
490 	 * error.
491 	 */
492 	if (e) {
493 		if (e < 0)
494 			return 1;
495 		if (loading)
496 			return 1;
497 		if (sourcing)
498 			(void)unstack();
499 		return 0;
500 	}
501 	if (com == NULL)
502 		return(0);
503 	if (value("autoprint") != NULL && com->c_argtype & P)
504 		if ((dot->m_flag & MDELETED) == 0) {
505 			muvec[0] = dot - &message[0] + 1;
506 			muvec[1] = 0;
507 			(void)type(muvec);
508 		}
509 	if (!sourcing && (com->c_argtype & T) == 0)
510 		sawcom = 1;
511 	return(0);
512 }
513 
514 /*
515  * Set the size of the message vector used to construct argument
516  * lists to message list functions.
517  */
518 void
519 setmsize(int sz)
520 {
521 
522 	if (msgvec != 0)
523 		free( msgvec);
524 	msgvec = calloc((size_t) (sz + 1), sizeof *msgvec);
525 }
526 
527 /*
528  * Find the correct command in the command table corresponding
529  * to the passed command "word"
530  */
531 
532 const struct cmd *
533 lex(char word[])
534 {
535 	const struct cmd *cp;
536 
537 	for (cp = &cmdtab[0]; cp->c_name != NULL; cp++)
538 		if (isprefix(word, cp->c_name))
539 			return(cp);
540 	return(NULL);
541 }
542 
543 /*
544  * Determine if as1 is a valid prefix of as2.
545  * Return true if yep.
546  */
547 int
548 isprefix(char *as1, const char *as2)
549 {
550 	char *s1;
551 	const char *s2;
552 
553 	s1 = as1;
554 	s2 = as2;
555 	while (*s1++ == *s2)
556 		if (*s2++ == '\0')
557 			return(1);
558 	return(*--s1 == '\0');
559 }
560 
561 /*
562  * The following gets called on receipt of an interrupt.  This is
563  * to abort printout of a command, mainly.
564  * Dispatching here when command() is inactive crashes rcv.
565  * Close all open files except 0, 1, 2, and the temporary.
566  * Also, unstack all source files.
567  */
568 
569 int	inithdr;			/* am printing startup headers */
570 
571 /*ARGSUSED*/
572 void
573 intr(int s)
574 {
575 
576 	noreset = 0;
577 	if (!inithdr)
578 		sawcom++;
579 	inithdr = 0;
580 	while (sourcing)
581 		(void)unstack();
582 
583 	close_all_files();
584 
585 	if (image >= 0) {
586 		(void)close(image);
587 		image = -1;
588 	}
589 	(void)fprintf(stderr, "Interrupt\n");
590 	reset(0);
591 }
592 
593 /*
594  * When we wake up after ^Z, reprint the prompt.
595  */
596 void
597 stop(int s)
598 {
599 	sig_t old_action = signal(s, SIG_DFL);
600 	sigset_t nset;
601 
602 	(void)sigemptyset(&nset);
603 	(void)sigaddset(&nset, s);
604 	(void)sigprocmask(SIG_UNBLOCK, &nset, NULL);
605 	(void)kill(0, s);
606 	(void)sigprocmask(SIG_BLOCK, &nset, NULL);
607 	(void)signal(s, old_action);
608 	if (reset_on_stop) {
609 		reset_on_stop = 0;
610 		reset(0);
611 	}
612 }
613 
614 /*
615  * Branch here on hangup signal and simulate "exit".
616  */
617 /*ARGSUSED*/
618 void
619 hangup(int s)
620 {
621 
622 	/* nothing to do? */
623 	exit(1);
624 }
625 
626 /*
627  * Announce the presence of the current Mail version,
628  * give the message count, and print a header listing.
629  */
630 void
631 announce(void)
632 {
633 	int vec[2], mdot;
634 
635 	mdot = newfileinfo(0);
636 	vec[0] = mdot;
637 	vec[1] = 0;
638 	dot = &message[mdot - 1];
639 	if (msgCount > 0 && value("noheader") == NULL) {
640 		inithdr++;
641 		(void)headers(vec);
642 		inithdr = 0;
643 	}
644 }
645 
646 /*
647  * Announce information about the file we are editing.
648  * Return a likely place to set dot.
649  */
650 int
651 newfileinfo(int omsgCount)
652 {
653 	struct message *mp;
654 	int u, n, mdot, d, s;
655 	size_t l;
656 	char fname[PATHSIZE], zname[PATHSIZE], *ename;
657 
658 	for (mp = &message[omsgCount]; mp < &message[msgCount]; mp++)
659 		if (mp->m_flag & MNEW)
660 			break;
661 	if (mp >= &message[msgCount])
662 		for (mp = &message[omsgCount]; mp < &message[msgCount]; mp++)
663 			if ((mp->m_flag & MREAD) == 0)
664 				break;
665 	if (mp < &message[msgCount])
666 		mdot = mp - &message[0] + 1;
667 	else
668 		mdot = omsgCount + 1;
669 	s = d = 0;
670 	for (mp = &message[0], n = 0, u = 0; mp < &message[msgCount]; mp++) {
671 		if (mp->m_flag & MNEW)
672 			n++;
673 		if ((mp->m_flag & MREAD) == 0)
674 			u++;
675 		if (mp->m_flag & MDELETED)
676 			d++;
677 		if (mp->m_flag & MSAVED)
678 			s++;
679 	}
680 	ename = mailname;
681 	if (getfold(fname) >= 0) {
682 		l = strlen(fname);
683 		if (l < PATHSIZE - 1)
684 			fname[l++] = '/';
685 		if (strncmp(fname, mailname, l) == 0) {
686 			(void)snprintf(zname, PATHSIZE, "+%s",
687 			    mailname + l);
688 			ename = zname;
689 		}
690 	}
691 	(void)printf("\"%s\": ", ename);
692 	if (msgCount == 1)
693 		(void)printf("1 message");
694 	else
695 		(void)printf("%d messages", msgCount);
696 	if (n > 0)
697 		(void)printf(" %d new", n);
698 	if (u-n > 0)
699 		(void)printf(" %d unread", u);
700 	if (d > 0)
701 		(void)printf(" %d deleted", d);
702 	if (s > 0)
703 		(void)printf(" %d saved", s);
704 	if (readonly)
705 		(void)printf(" [Read only]");
706 	(void)printf("\n");
707 	return(mdot);
708 }
709 
710 /*
711  * Print the current version number.
712  */
713 
714 /*ARGSUSED*/
715 int
716 pversion(void *v)
717 {
718 	(void)printf("Version %s\n", version);
719 	return(0);
720 }
721 
722 /*
723  * Load a file of user definitions.
724  */
725 void
726 load(const char *name)
727 {
728 	FILE *in, *oldin;
729 
730 	if ((in = Fopen(name, "r")) == NULL)
731 		return;
732 	oldin = input;
733 	input = in;
734 	loading = 1;
735 	sourcing = 1;
736 	commands();
737 	loading = 0;
738 	sourcing = 0;
739 	input = oldin;
740 	(void)Fclose(in);
741 }
742