xref: /dragonfly/usr.bin/mail/lex.c (revision ed36d35d)
1 /*
2  * Copyright (c) 1980, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. Neither the name of the University nor the names of its contributors
14  *    may be used to endorse or promote products derived from this software
15  *    without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  *
29  * @(#)lex.c	8.2 (Berkeley) 4/20/95
30  * $FreeBSD: src/usr.bin/mail/lex.c,v 1.5.6.5 2003/01/06 05:46:03 mikeh Exp $
31  */
32 
33 #include "rcv.h"
34 #include <errno.h>
35 #include <fcntl.h>
36 #include "extern.h"
37 
38 /*
39  * Mail -- a mail program
40  *
41  * Lexical processing of commands.
42  */
43 
44 const char	*prompt = "& ";
45 
46 extern const struct cmd cmdtab[];
47 extern const char *version;
48 
49 /*
50  * Set up editing on the given file name.
51  * If the first character of name is %, we are considered to be
52  * editing the file, otherwise we are reading our mail which has
53  * signficance for mbox and so forth.
54  *
55  * If the -e option is passed to mail, this function has a
56  * tri-state return code: -1 on error, 0 on no mail, 1 if there is
57  * mail.
58  */
59 int
60 setfile(char *name)
61 {
62 	FILE *ibuf;
63 	int checkmode, i, fd;
64 	struct stat stb;
65 	char isedit = *name != '%' || getuserid(myname) != getuid();
66 	char *who = name[1] ? name + 1 : myname;
67 	char tempname[PATHSIZE];
68 	static int shudclob;
69 
70 	checkmode = value("checkmode") != NULL;
71 
72 	if ((name = expand(name)) == NULL)
73 		return (-1);
74 
75 	if ((ibuf = Fopen(name, "r")) == NULL) {
76 		if (!isedit && errno == ENOENT)
77 			goto nomail;
78 		warn("%s", name);
79 		return (-1);
80 	}
81 
82 	if (fstat(fileno(ibuf), &stb) < 0) {
83 		warn("fstat");
84 		Fclose(ibuf);
85 		return (-1);
86 	}
87 
88 	if (S_ISDIR(stb.st_mode) || !S_ISREG(stb.st_mode)) {
89 		Fclose(ibuf);
90 		errno = S_ISDIR(stb.st_mode) ? EISDIR : EINVAL;
91 		warn("%s", name);
92 		return (-1);
93 	}
94 
95 	/*
96 	 * Looks like all will be well.  We must now relinquish our
97 	 * hold on the current set of stuff.  Must hold signals
98 	 * while we are reading the new file, else we will ruin
99 	 * the message[] data structure.
100 	 */
101 
102 	holdsigs();
103 	if (shudclob)
104 		quit();
105 
106 	/*
107 	 * Copy the messages into /tmp
108 	 * and set pointers.
109 	 */
110 
111 	readonly = 0;
112 	if ((i = open(name, 1)) < 0)
113 		readonly++;
114 	else
115 		close(i);
116 	if (shudclob) {
117 		fclose(itf);
118 		fclose(otf);
119 	}
120 	shudclob = 1;
121 	edit = isedit;
122 	strlcpy(prevfile, mailname, sizeof(prevfile));
123 	if (name != mailname)
124 		strlcpy(mailname, name, sizeof(mailname));
125 	mailsize = fsize(ibuf);
126 	snprintf(tempname, sizeof(tempname), "%s/mail.RxXXXXXXXXXX", tmpdir);
127 	if ((fd = mkstemp(tempname)) == -1 || (otf = fdopen(fd, "w")) == NULL)
128 		err(1, "%s", tempname);
129 	fcntl(fileno(otf), F_SETFD, 1);
130 	if ((itf = fopen(tempname, "r")) == NULL)
131 		err(1, "%s", tempname);
132 	fcntl(fileno(itf), F_SETFD, 1);
133 	rm(tempname);
134 	setptr(ibuf, 0);
135 	setmsize(msgCount);
136 	/*
137 	 * New mail may have arrived while we were reading
138 	 * the mail file, so reset mailsize to be where
139 	 * we really are in the file...
140 	 */
141 	mailsize = ftello(ibuf);
142 	Fclose(ibuf);
143 	relsesigs();
144 	sawcom = 0;
145 	if ((checkmode || !edit) && msgCount == 0) {
146 nomail:
147 		if (!checkmode) {
148 			fprintf(stderr, "No mail for %s\n", who);
149 			return (-1);
150 		} else {
151 			return (0);
152 		}
153 	}
154 	return (checkmode ? 1 : 0);
155 }
156 
157 /*
158  * Incorporate any new mail that has arrived since we first
159  * started reading mail.
160  */
161 int
162 incfile(void)
163 {
164 	off_t newsize;
165 	int omsgCount = msgCount;
166 	FILE *ibuf;
167 
168 	ibuf = Fopen(mailname, "r");
169 	if (ibuf == NULL)
170 		return (-1);
171 	holdsigs();
172 	newsize = fsize(ibuf);
173 	if (newsize == 0)
174 		return (-1);		/* mail box is now empty??? */
175 	if (newsize < mailsize)
176 		return (-1);		/* mail box has shrunk??? */
177 	if (newsize == mailsize)
178 		return (0);		/* no new mail */
179 	setptr(ibuf, mailsize);
180 	setmsize(msgCount);
181 	mailsize = ftello(ibuf);
182 	Fclose(ibuf);
183 	relsesigs();
184 	return (msgCount - omsgCount);
185 }
186 
187 int	*msgvec;
188 int	reset_on_stop;			/* do a reset() if stopped */
189 
190 /*
191  * Interpret user commands one by one.  If standard input is not a tty,
192  * print no prompt.
193  */
194 void
195 commands(void)
196 {
197 	int n, eofloop = 0;
198 	char linebuf[LINESIZE];
199 
200 	if (!sourcing) {
201 		if (signal(SIGINT, SIG_IGN) != SIG_IGN)
202 			signal(SIGINT, intr);
203 		if (signal(SIGHUP, SIG_IGN) != SIG_IGN)
204 			signal(SIGHUP, hangup);
205 		signal(SIGTSTP, stop);
206 		signal(SIGTTOU, stop);
207 		signal(SIGTTIN, stop);
208 	}
209 	setexit();
210 	for (;;) {
211 		/*
212 		 * Print the prompt, if needed.  Clear out
213 		 * string space, and flush the output.
214 		 */
215 		if (!sourcing && value("interactive") != NULL) {
216 			if ((value("autoinc") != NULL) && (incfile() > 0))
217 				printf("New mail has arrived.\n");
218 			reset_on_stop = 1;
219 			printf("%s", prompt);
220 		}
221 		fflush(stdout);
222 		sreset();
223 		/*
224 		 * Read a line of commands from the current input
225 		 * and handle end of file specially.
226 		 */
227 		n = 0;
228 		for (;;) {
229 			if (readline(input, &linebuf[n], LINESIZE - n) < 0) {
230 				if (n == 0)
231 					n = -1;
232 				break;
233 			}
234 			if ((n = strlen(linebuf)) == 0)
235 				break;
236 			n--;
237 			if (linebuf[n] != '\\')
238 				break;
239 			linebuf[n++] = ' ';
240 		}
241 		reset_on_stop = 0;
242 		if (n < 0) {
243 				/* eof */
244 			if (loading)
245 				break;
246 			if (sourcing) {
247 				unstack();
248 				continue;
249 			}
250 			if (value("interactive") != NULL &&
251 			    value("ignoreeof") != NULL &&
252 			    ++eofloop < 25) {
253 				printf("Use \"quit\" to quit.\n");
254 				continue;
255 			}
256 			break;
257 		}
258 		eofloop = 0;
259 		if (execute(linebuf, 0))
260 			break;
261 	}
262 }
263 
264 /*
265  * Execute a single command.
266  * Command functions return 0 for success, 1 for error, and -1
267  * for abort.  A 1 or -1 aborts a load or source.  A -1 aborts
268  * the interactive command loop.
269  * Contxt is non-zero if called while composing mail.
270  */
271 int
272 execute(char *linebuf, int contxt)
273 {
274 	char word[LINESIZE];
275 	char *arglist[MAXARGC];
276 	const struct cmd *com;
277 	char *cp, *cp2;
278 	int c, muvec[2];
279 	int e = 1;
280 
281 	/*
282 	 * Strip the white space away from the beginning
283 	 * of the command, then scan out a word, which
284 	 * consists of anything except digits and white space.
285 	 *
286 	 * Handle ! escapes differently to get the correct
287 	 * lexical conventions.
288 	 */
289 
290 	for (cp = linebuf; isspace((unsigned char)*cp); cp++)
291 		;
292 	if (*cp == '!') {
293 		if (sourcing) {
294 			printf("Can't \"!\" while sourcing\n");
295 			goto out;
296 		}
297 		shell(cp+1);
298 		return (0);
299 	}
300 	cp2 = word;
301 	while (*cp != '\0' && strchr(" \t0123456789$^.:/-+*'\"", *cp) == NULL)
302 		*cp2++ = *cp++;
303 	*cp2 = '\0';
304 
305 	/*
306 	 * Look up the command; if not found, bitch.
307 	 * Normally, a blank command would map to the
308 	 * first command in the table; while sourcing,
309 	 * however, we ignore blank lines to eliminate
310 	 * confusion.
311 	 */
312 
313 	if (sourcing && *word == '\0')
314 		return (0);
315 	com = lex(word);
316 	if (com == NULL) {
317 		printf("Unknown command: \"%s\"\n", word);
318 		goto out;
319 	}
320 
321 	/*
322 	 * See if we should execute the command -- if a conditional
323 	 * we always execute it, otherwise, check the state of cond.
324 	 */
325 
326 	if ((com->c_argtype & F) == 0)
327 		if ((cond == CRCV && !rcvmode) || (cond == CSEND && rcvmode))
328 			return (0);
329 
330 	/*
331 	 * Process the arguments to the command, depending
332 	 * on the type he expects.  Default to an error.
333 	 * If we are sourcing an interactive command, it's
334 	 * an error.
335 	 */
336 
337 	if (!rcvmode && (com->c_argtype & M) == 0) {
338 		printf("May not execute \"%s\" while sending\n",
339 		    com->c_name);
340 		goto out;
341 	}
342 	if (sourcing && com->c_argtype & I) {
343 		printf("May not execute \"%s\" while sourcing\n",
344 		    com->c_name);
345 		goto out;
346 	}
347 	if (readonly && com->c_argtype & W) {
348 		printf("May not execute \"%s\" -- message file is read only\n",
349 		   com->c_name);
350 		goto out;
351 	}
352 	if (contxt && com->c_argtype & R) {
353 		printf("Cannot recursively invoke \"%s\"\n", com->c_name);
354 		goto out;
355 	}
356 	switch (com->c_argtype & ~(F|P|I|M|T|W|R)) {
357 	case MSGLIST:
358 		/*
359 		 * A message list defaulting to nearest forward
360 		 * legal message.
361 		 */
362 		if (msgvec == NULL) {
363 			printf("Illegal use of \"message list\"\n");
364 			break;
365 		}
366 		if ((c = getmsglist(cp, msgvec, com->c_msgflag)) < 0)
367 			break;
368 		if (c  == 0) {
369 			*msgvec = first(com->c_msgflag, com->c_msgmask);
370 			msgvec[1] = 0;
371 		}
372 		if (*msgvec == 0) {
373 			printf("No applicable messages\n");
374 			break;
375 		}
376 		e = (*com->c_func)(msgvec);
377 		break;
378 
379 	case NDMLIST:
380 		/*
381 		 * A message list with no defaults, but no error
382 		 * if none exist.
383 		 */
384 		if (msgvec == NULL) {
385 			printf("Illegal use of \"message list\"\n");
386 			break;
387 		}
388 		if (getmsglist(cp, msgvec, com->c_msgflag) < 0)
389 			break;
390 		e = (*com->c_func)(msgvec);
391 		break;
392 
393 	case STRLIST:
394 		/*
395 		 * Just the straight string, with
396 		 * leading blanks removed.
397 		 */
398 		while (isspace((unsigned char)*cp))
399 			cp++;
400 		e = (*com->c_func)(cp);
401 		break;
402 
403 	case RAWLIST:
404 		/*
405 		 * A vector of strings, in shell style.
406 		 */
407 		if ((c = getrawlist(cp, arglist,
408 		    sizeof(arglist) / sizeof(*arglist))) < 0)
409 			break;
410 		if (c < com->c_minargs) {
411 			printf("%s requires at least %d arg(s)\n",
412 			    com->c_name, com->c_minargs);
413 			break;
414 		}
415 		if (c > com->c_maxargs) {
416 			printf("%s takes no more than %d arg(s)\n",
417 			    com->c_name, com->c_maxargs);
418 			break;
419 		}
420 		e = (*com->c_func)(arglist);
421 		break;
422 
423 	case NOLIST:
424 		/*
425 		 * Just the constant zero, for exiting,
426 		 * eg.
427 		 */
428 		e = (*com->c_func)(0);
429 		break;
430 
431 	default:
432 		errx(1, "Unknown argtype");
433 	}
434 
435 out:
436 	/*
437 	 * Exit the current source file on
438 	 * error.
439 	 */
440 	if (e) {
441 		if (e < 0)
442 			return (1);
443 		if (loading)
444 			return (1);
445 		if (sourcing)
446 			unstack();
447 		return (0);
448 	}
449 	if (com == NULL)
450 		return (0);
451 	if (value("autoprint") != NULL && com->c_argtype & P)
452 		if ((dot->m_flag & MDELETED) == 0) {
453 			muvec[0] = dot - &message[0] + 1;
454 			muvec[1] = 0;
455 			type(muvec);
456 		}
457 	if (!sourcing && (com->c_argtype & T) == 0)
458 		sawcom = 1;
459 	return (0);
460 }
461 
462 /*
463  * Set the size of the message vector used to construct argument
464  * lists to message list functions.
465  */
466 void
467 setmsize(int sz)
468 {
469 	if (msgvec != NULL)
470 		free(msgvec);
471 	msgvec = calloc((unsigned)(sz + 1), sizeof(*msgvec));
472 }
473 
474 /*
475  * Find the correct command in the command table corresponding
476  * to the passed command "word"
477  */
478 
479 const struct cmd *
480 lex(char *word)
481 {
482 	const struct cmd *cp;
483 
484 	/*
485 	 * ignore trailing chars after `#'
486 	 *
487 	 * lines with beginning `#' are comments
488 	 * spaces before `#' are ignored in execute()
489 	 */
490 
491 	if (*word == '#')
492 	    *(word+1) = '\0';
493 
494 
495 	for (cp = &cmdtab[0]; cp->c_name != NULL; cp++)
496 		if (isprefix(word, cp->c_name))
497 			return (cp);
498 	return (NULL);
499 }
500 
501 /*
502  * Determine if as1 is a valid prefix of as2.
503  * Return true if yep.
504  */
505 int
506 isprefix(const char *as1, const char *as2)
507 {
508 	const char *s1, *s2;
509 
510 	s1 = as1;
511 	s2 = as2;
512 	while (*s1++ == *s2)
513 		if (*s2++ == '\0')
514 			return (1);
515 	return (*--s1 == '\0');
516 }
517 
518 /*
519  * The following gets called on receipt of an interrupt.  This is
520  * to abort printout of a command, mainly.
521  * Dispatching here when command() is inactive crashes rcv.
522  * Close all open files except 0, 1, 2, and the temporary.
523  * Also, unstack all source files.
524  */
525 
526 int	inithdr;			/* am printing startup headers */
527 
528 /*ARGSUSED*/
529 void
530 intr(int s)
531 {
532 	noreset = 0;
533 	if (!inithdr)
534 		sawcom++;
535 	inithdr = 0;
536 	while (sourcing)
537 		unstack();
538 
539 	close_all_files();
540 
541 	if (image >= 0) {
542 		close(image);
543 		image = -1;
544 	}
545 	fprintf(stderr, "Interrupt\n");
546 	reset(0);
547 }
548 
549 /*
550  * When we wake up after ^Z, reprint the prompt.
551  */
552 void
553 stop(int s)
554 {
555 	sig_t old_action = signal(s, SIG_DFL);
556 	sigset_t nset;
557 
558 	sigemptyset(&nset);
559 	sigaddset(&nset, s);
560 	sigprocmask(SIG_UNBLOCK, &nset, NULL);
561 	kill(0, s);
562 	sigprocmask(SIG_BLOCK, &nset, NULL);
563 	signal(s, old_action);
564 	if (reset_on_stop) {
565 		reset_on_stop = 0;
566 		reset(0);
567 	}
568 }
569 
570 /*
571  * Branch here on hangup signal and simulate "exit".
572  */
573 /*ARGSUSED*/
574 void
575 hangup(int s)
576 {
577 	/* nothing to do? */
578 	exit(1);
579 }
580 
581 /*
582  * Announce the presence of the current Mail version,
583  * give the message count, and print a header listing.
584  */
585 void
586 announce(void)
587 {
588 	int vec[2], mdot;
589 
590 	mdot = newfileinfo(0);
591 	vec[0] = mdot;
592 	vec[1] = 0;
593 	dot = &message[mdot - 1];
594 	if (msgCount > 0 && value("noheader") == NULL) {
595 		inithdr++;
596 		headers(vec);
597 		inithdr = 0;
598 	}
599 }
600 
601 /*
602  * Announce information about the file we are editing.
603  * Return a likely place to set dot.
604  */
605 int
606 newfileinfo(int omsgCount)
607 {
608 	struct message *mp;
609 	int u, n, mdot, d, s;
610 	char fname[PATHSIZE+1], zname[PATHSIZE+1], *ename;
611 
612 	for (mp = &message[omsgCount]; mp < &message[msgCount]; mp++)
613 		if (mp->m_flag & MNEW)
614 			break;
615 	if (mp >= &message[msgCount])
616 		for (mp = &message[omsgCount]; mp < &message[msgCount]; mp++)
617 			if ((mp->m_flag & MREAD) == 0)
618 				break;
619 	if (mp < &message[msgCount])
620 		mdot = mp - &message[0] + 1;
621 	else
622 		mdot = omsgCount + 1;
623 	s = d = 0;
624 	for (mp = &message[0], n = 0, u = 0; mp < &message[msgCount]; mp++) {
625 		if (mp->m_flag & MNEW)
626 			n++;
627 		if ((mp->m_flag & MREAD) == 0)
628 			u++;
629 		if (mp->m_flag & MDELETED)
630 			d++;
631 		if (mp->m_flag & MSAVED)
632 			s++;
633 	}
634 	ename = mailname;
635 	if (getfold(fname, sizeof(fname) - 1) >= 0) {
636 		strcat(fname, "/");
637 		if (strncmp(fname, mailname, strlen(fname)) == 0) {
638 			snprintf(zname, sizeof(zname), "+%s",
639 			    mailname + strlen(fname));
640 			ename = zname;
641 		}
642 	}
643 	printf("\"%s\": ", ename);
644 	if (msgCount == 1)
645 		printf("1 message");
646 	else
647 		printf("%d messages", msgCount);
648 	if (n > 0)
649 		printf(" %d new", n);
650 	if (u-n > 0)
651 		printf(" %d unread", u);
652 	if (d > 0)
653 		printf(" %d deleted", d);
654 	if (s > 0)
655 		printf(" %d saved", s);
656 	if (readonly)
657 		printf(" [Read only]");
658 	printf("\n");
659 	return (mdot);
660 }
661 
662 /*
663  * Print the current version number.
664  */
665 
666 /*ARGSUSED*/
667 int
668 pversion(int e)
669 {
670 	printf("Version %s\n", version);
671 	return (0);
672 }
673 
674 /*
675  * Load a file of user definitions.
676  */
677 void
678 load(char *name)
679 {
680 	FILE *in, *oldin;
681 
682 	if ((in = Fopen(name, "r")) == NULL)
683 		return;
684 	oldin = input;
685 	input = in;
686 	loading = 1;
687 	sourcing = 1;
688 	commands();
689 	loading = 0;
690 	sourcing = 0;
691 	input = oldin;
692 	Fclose(in);
693 }
694