xref: /netbsd-src/usr.bin/mail/lex.c (revision 1ad9454efb13a65cd7535ccf867508cb14d9d30e)
1 /*	$NetBSD: lex.c,v 1.26 2006/09/18 19:46:21 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 1.26 2006/09/18 19:46:21 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 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 			(void)signal(SIGINT, intr);
217 		if (signal(SIGHUP, SIG_IGN) != SIG_IGN)
218 			(void)signal(SIGHUP, hangup);
219 		(void)signal(SIGTSTP, stop);
220 		(void)signal(SIGTTOU, stop);
221 		(void)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 				(void)printf("New mail has arrived.\n");
232 			reset_on_stop = 1;
233 #ifndef USE_READLINE
234 			(void)printf("%s", prompt);
235 #endif
236 		}
237 		(void)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 #ifdef USE_READLINE
246 			if (!sourcing) {
247 				char *line;
248 
249 				if ((line = rl_gets(prompt)) == NULL) {
250 					if (n == 0)
251 						n = -1;
252 					break;
253 				}
254 				strncpy(linebuf, line, LINESIZE);
255 			}
256 			else {
257 				if (readline(input, &linebuf[n], LINESIZE - n) < 0) {
258 					if (n == 0)
259 						n = -1;
260 					break;
261 				}
262 			}
263 #else /* USE_READLINE */
264 			if (readline(input, &linebuf[n], LINESIZE - n) < 0) {
265 				if (n == 0)
266 					n = -1;
267 				break;
268 			}
269 #endif /* USE_READLINE */
270 
271 			if (sourcing) {  /* allow comments in source files */
272 				char *ptr = strchr(linebuf, '#');
273 				if (ptr)
274 					*ptr = '\0';
275 			}
276 			if ((n = strlen(linebuf)) == 0)
277 				break;
278 			n--;
279 			if (linebuf[n] != '\\')
280 				break;
281 			linebuf[n++] = ' ';
282 		}
283 		reset_on_stop = 0;
284 		if (n < 0) {
285 				/* eof */
286 			if (loading)
287 				break;
288 			if (sourcing) {
289 				(void)unstack();
290 				continue;
291 			}
292 #ifdef USE_READLINE
293 			{
294 				char *p;
295 				if (value("interactive") != NULL &&
296 				    (p=value("ignoreeof")) != NULL &&
297 				    ++eofloop < (*p==0 ? 25 : atoi(p))) {
298 					(void)printf("Use \"quit\" to quit.\n");
299 					continue;
300 				}
301 			}
302 #else
303 			if (value("interactive") != NULL &&
304 			    value("ignoreeof") != NULL &&
305 			    ++eofloop < 25) {
306 				(void)printf("Use \"quit\" to quit.\n");
307 				continue;
308 			}
309 #endif
310 			break;
311 		}
312 		eofloop = 0;
313 		if (execute(linebuf, 0))
314 			break;
315 	}
316 }
317 
318 /*
319  * Execute a single command.
320  * Command functions return 0 for success, 1 for error, and -1
321  * for abort.  A 1 or -1 aborts a load or source.  A -1 aborts
322  * the interactive command loop.
323  * Contxt is non-zero if called while composing mail.
324  */
325 int
326 execute(char linebuf[], int contxt)
327 {
328 	char word[LINESIZE];
329 	char *arglist[MAXARGC];
330 	const struct cmd *com = NULL;
331 	char *cp, *cp2;
332 	int c;
333 	int muvec[2];
334 	int e = 1;
335 
336 	/*
337 	 * Strip the white space away from the beginning
338 	 * of the command, then scan out a word, which
339 	 * consists of anything except digits and white space.
340 	 *
341 	 * Handle ! escapes differently to get the correct
342 	 * lexical conventions.
343 	 */
344 
345 	for (cp = linebuf; isspace((unsigned char)*cp); cp++)
346 		;
347 	if (*cp == '!') {
348 		if (sourcing) {
349 			(void)printf("Can't \"!\" while sourcing\n");
350 			goto out;
351 		}
352 		(void)shell(cp+1);
353 		return(0);
354 	}
355 	cp2 = word;
356 	while (*cp && strchr(" \t0123456789$^.:/-+*'\"", *cp) == NULL)
357 		*cp2++ = *cp++;
358 	*cp2 = '\0';
359 
360 	/*
361 	 * Look up the command; if not found, bitch.
362 	 * Normally, a blank command would map to the
363 	 * first command in the table; while sourcing,
364 	 * however, we ignore blank lines to eliminate
365 	 * confusion.
366 	 */
367 
368 	if (sourcing && *word == '\0')
369 		return(0);
370 	com = lex(word);
371 	if (com == NULL) {
372 		(void)printf("Unknown command: \"%s\"\n", word);
373 		goto out;
374 	}
375 
376 	/*
377 	 * See if we should execute the command -- if a conditional
378 	 * we always execute it, otherwise, check the state of cond.
379 	 */
380 
381 	if ((com->c_argtype & F) == 0)
382 		if ((cond == CRCV && !rcvmode) || (cond == CSEND && rcvmode))
383 			return(0);
384 
385 	/*
386 	 * Process the arguments to the command, depending
387 	 * on the type he expects.  Default to an error.
388 	 * If we are sourcing an interactive command, it's
389 	 * an error.
390 	 */
391 
392 	if (!rcvmode && (com->c_argtype & M) == 0) {
393 		(void)printf("May not execute \"%s\" while sending\n",
394 		    com->c_name);
395 		goto out;
396 	}
397 	if (sourcing && com->c_argtype & I) {
398 		(void)printf("May not execute \"%s\" while sourcing\n",
399 		    com->c_name);
400 		goto out;
401 	}
402 	if (readonly && com->c_argtype & W) {
403 		(void)printf("May not execute \"%s\" -- message file is read only\n",
404 		   com->c_name);
405 		goto out;
406 	}
407 	if (contxt && com->c_argtype & R) {
408 		(void)printf("Cannot recursively invoke \"%s\"\n", com->c_name);
409 		goto out;
410 	}
411 	switch (com->c_argtype & ~(F|P|I|M|T|W|R)) {
412 	case MSGLIST:
413 		/*
414 		 * A message list defaulting to nearest forward
415 		 * legal message.
416 		 */
417 		if (msgvec == 0) {
418 			(void)printf("Illegal use of \"message list\"\n");
419 			break;
420 		}
421 		if ((c = getmsglist(cp, msgvec, com->c_msgflag)) < 0)
422 			break;
423 		if (c  == 0) {
424 			*msgvec = first(com->c_msgflag,
425 				com->c_msgmask);
426 			msgvec[1] = 0;
427 		}
428 		if (*msgvec == 0) {
429 			(void)printf("No applicable messages\n");
430 			break;
431 		}
432 		e = (*com->c_func)(msgvec);
433 		break;
434 
435 	case NDMLIST:
436 		/*
437 		 * A message list with no defaults, but no error
438 		 * if none exist.
439 		 */
440 		if (msgvec == 0) {
441 			(void)printf("Illegal use of \"message list\"\n");
442 			break;
443 		}
444 		if (getmsglist(cp, msgvec, com->c_msgflag) < 0)
445 			break;
446 		e = (*com->c_func)(msgvec);
447 		break;
448 
449 	case STRLIST:
450 		/*
451 		 * Just the straight string, with
452 		 * leading blanks removed.
453 		 */
454 		while (isspace((unsigned char)*cp))
455 			cp++;
456 		e = (*com->c_func)(cp);
457 		break;
458 
459 	case RAWLIST:
460 		/*
461 		 * A vector of strings, in shell style.
462 		 */
463 		if ((c = getrawlist(cp, arglist,
464 				sizeof arglist / sizeof *arglist)) < 0)
465 			break;
466 		if (c < com->c_minargs) {
467 			(void)printf("%s requires at least %d arg(s)\n",
468 				com->c_name, com->c_minargs);
469 			break;
470 		}
471 		if (c > com->c_maxargs) {
472 			(void)printf("%s takes no more than %d arg(s)\n",
473 				com->c_name, com->c_maxargs);
474 			break;
475 		}
476 		e = (*com->c_func)(arglist);
477 		break;
478 
479 	case NOLIST:
480 		/*
481 		 * Just the constant zero, for exiting,
482 		 * eg.
483 		 */
484 		e = (*com->c_func)(0);
485 		break;
486 
487 	default:
488 		errx(1, "Unknown argtype");
489 	}
490 
491 out:
492 	/*
493 	 * Exit the current source file on
494 	 * error.
495 	 */
496 	if (e) {
497 		if (e < 0)
498 			return 1;
499 		if (loading)
500 			return 1;
501 		if (sourcing)
502 			(void)unstack();
503 		return 0;
504 	}
505 	if (com == NULL)
506 		return(0);
507 	if (value("autoprint") != NULL && com->c_argtype & P)
508 		if ((dot->m_flag & MDELETED) == 0) {
509 			muvec[0] = dot - &message[0] + 1;
510 			muvec[1] = 0;
511 			(void)type(muvec);
512 		}
513 	if (!sourcing && (com->c_argtype & T) == 0)
514 		sawcom = 1;
515 	return(0);
516 }
517 
518 /*
519  * Set the size of the message vector used to construct argument
520  * lists to message list functions.
521  */
522 void
523 setmsize(int sz)
524 {
525 
526 	if (msgvec != 0)
527 		free( msgvec);
528 	msgvec = calloc((size_t) (sz + 1), sizeof *msgvec);
529 }
530 
531 /*
532  * Find the correct command in the command table corresponding
533  * to the passed command "word"
534  */
535 
536 const struct cmd *
537 lex(char word[])
538 {
539 	const struct cmd *cp;
540 
541 	for (cp = &cmdtab[0]; cp->c_name != NULL; cp++)
542 		if (isprefix(word, cp->c_name))
543 			return(cp);
544 	return(NULL);
545 }
546 
547 /*
548  * Determine if as1 is a valid prefix of as2.
549  * Return true if yep.
550  */
551 int
552 isprefix(char *as1, const char *as2)
553 {
554 	char *s1;
555 	const char *s2;
556 
557 	s1 = as1;
558 	s2 = as2;
559 	while (*s1++ == *s2)
560 		if (*s2++ == '\0')
561 			return(1);
562 	return(*--s1 == '\0');
563 }
564 
565 /*
566  * The following gets called on receipt of an interrupt.  This is
567  * to abort printout of a command, mainly.
568  * Dispatching here when command() is inactive crashes rcv.
569  * Close all open files except 0, 1, 2, and the temporary.
570  * Also, unstack all source files.
571  */
572 
573 int	inithdr;			/* am printing startup headers */
574 
575 /*ARGSUSED*/
576 void
577 intr(int s)
578 {
579 
580 	noreset = 0;
581 	if (!inithdr)
582 		sawcom++;
583 	inithdr = 0;
584 	while (sourcing)
585 		(void)unstack();
586 
587 	close_all_files();
588 
589 	if (image >= 0) {
590 		(void)close(image);
591 		image = -1;
592 	}
593 	(void)fprintf(stderr, "Interrupt\n");
594 	reset(0);
595 }
596 
597 /*
598  * When we wake up after ^Z, reprint the prompt.
599  */
600 void
601 stop(int s)
602 {
603 	sig_t old_action = signal(s, SIG_DFL);
604 	sigset_t nset;
605 
606 	(void)sigemptyset(&nset);
607 	(void)sigaddset(&nset, s);
608 	(void)sigprocmask(SIG_UNBLOCK, &nset, NULL);
609 	(void)kill(0, s);
610 	(void)sigprocmask(SIG_BLOCK, &nset, NULL);
611 	(void)signal(s, old_action);
612 	if (reset_on_stop) {
613 		reset_on_stop = 0;
614 		reset(0);
615 	}
616 }
617 
618 /*
619  * Branch here on hangup signal and simulate "exit".
620  */
621 /*ARGSUSED*/
622 void
623 hangup(int s)
624 {
625 
626 	/* nothing to do? */
627 	exit(1);
628 }
629 
630 /*
631  * Announce the presence of the current Mail version,
632  * give the message count, and print a header listing.
633  */
634 void
635 announce(void)
636 {
637 	int vec[2], mdot;
638 
639 	mdot = newfileinfo(0);
640 	vec[0] = mdot;
641 	vec[1] = 0;
642 	dot = &message[mdot - 1];
643 	if (msgCount > 0 && value("noheader") == NULL) {
644 		inithdr++;
645 		(void)headers(vec);
646 		inithdr = 0;
647 	}
648 }
649 
650 /*
651  * Announce information about the file we are editing.
652  * Return a likely place to set dot.
653  */
654 int
655 newfileinfo(int omsgCount)
656 {
657 	struct message *mp;
658 	int u, n, mdot, d, s;
659 	size_t l;
660 	char fname[PATHSIZE], zname[PATHSIZE], *ename;
661 
662 	for (mp = &message[omsgCount]; mp < &message[msgCount]; mp++)
663 		if (mp->m_flag & MNEW)
664 			break;
665 	if (mp >= &message[msgCount])
666 		for (mp = &message[omsgCount]; mp < &message[msgCount]; mp++)
667 			if ((mp->m_flag & MREAD) == 0)
668 				break;
669 	if (mp < &message[msgCount])
670 		mdot = mp - &message[0] + 1;
671 	else
672 		mdot = omsgCount + 1;
673 	s = d = 0;
674 	for (mp = &message[0], n = 0, u = 0; mp < &message[msgCount]; mp++) {
675 		if (mp->m_flag & MNEW)
676 			n++;
677 		if ((mp->m_flag & MREAD) == 0)
678 			u++;
679 		if (mp->m_flag & MDELETED)
680 			d++;
681 		if (mp->m_flag & MSAVED)
682 			s++;
683 	}
684 	ename = mailname;
685 	if (getfold(fname) >= 0) {
686 		l = strlen(fname);
687 		if (l < PATHSIZE - 1)
688 			fname[l++] = '/';
689 		if (strncmp(fname, mailname, l) == 0) {
690 			(void)snprintf(zname, PATHSIZE, "+%s",
691 			    mailname + l);
692 			ename = zname;
693 		}
694 	}
695 	(void)printf("\"%s\": ", ename);
696 	if (msgCount == 1)
697 		(void)printf("1 message");
698 	else
699 		(void)printf("%d messages", msgCount);
700 	if (n > 0)
701 		(void)printf(" %d new", n);
702 	if (u-n > 0)
703 		(void)printf(" %d unread", u);
704 	if (d > 0)
705 		(void)printf(" %d deleted", d);
706 	if (s > 0)
707 		(void)printf(" %d saved", s);
708 	if (readonly)
709 		(void)printf(" [Read only]");
710 	(void)printf("\n");
711 	return(mdot);
712 }
713 
714 /*
715  * Print the current version number.
716  */
717 
718 /*ARGSUSED*/
719 int
720 pversion(void *v)
721 {
722 	(void)printf("Version %s\n", version);
723 	return(0);
724 }
725 
726 /*
727  * Load a file of user definitions.
728  */
729 void
730 load(const char *name)
731 {
732 	FILE *in, *oldin;
733 
734 	if ((in = Fopen(name, "r")) == NULL)
735 		return;
736 	oldin = input;
737 	input = in;
738 	loading = 1;
739 	sourcing = 1;
740 	commands();
741 	loading = 0;
742 	sourcing = 0;
743 	input = oldin;
744 	(void)Fclose(in);
745 }
746