xref: /freebsd/usr.bin/mail/lex.c (revision 6990ffd8a95caaba6858ad44ff1b3157d1efba8f)
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. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by the University of
16  *	California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 #ifndef lint
35 #if 0
36 static char sccsid[] = "@(#)lex.c	8.1 (Berkeley) 6/6/93";
37 #endif
38 static const char rcsid[] =
39   "$FreeBSD$";
40 #endif /* not lint */
41 
42 #include "rcv.h"
43 #include <errno.h>
44 #include <fcntl.h>
45 #include "extern.h"
46 
47 /*
48  * Mail -- a mail program
49  *
50  * Lexical processing of commands.
51  */
52 
53 const char	*prompt = "& ";
54 
55 extern const struct cmd cmdtab[];
56 extern const char *version;
57 
58 /*
59  * Set up editing on the given file name.
60  * If the first character of name is %, we are considered to be
61  * editing the file, otherwise we are reading our mail which has
62  * signficance for mbox and so forth.
63  */
64 int
65 setfile(name)
66 	char *name;
67 {
68 	FILE *ibuf;
69 	int i, fd;
70 	struct stat stb;
71 	char isedit = *name != '%';
72 	char *who = name[1] ? name + 1 : myname;
73 	char tempname[PATHSIZE];
74 	static int shudclob;
75 
76 	if ((name = expand(name)) == NULL)
77 		return (-1);
78 
79 	if ((ibuf = Fopen(name, "r")) == NULL) {
80 		if (!isedit && errno == ENOENT)
81 			goto nomail;
82 		warn("%s", name);
83 		return (-1);
84 	}
85 
86 	if (fstat(fileno(ibuf), &stb) < 0) {
87 		warn("fstat");
88 		(void)Fclose(ibuf);
89 		return (-1);
90 	}
91 
92 	if (S_ISDIR(stb.st_mode) || !S_ISREG(stb.st_mode)) {
93 		(void)Fclose(ibuf);
94 		errno = S_ISDIR(stb.st_mode) ? EISDIR : EINVAL;
95 		warn("%s", name);
96 		return (-1);
97 	}
98 
99 	/*
100 	 * Looks like all will be well.  We must now relinquish our
101 	 * hold on the current set of stuff.  Must hold signals
102 	 * while we are reading the new file, else we will ruin
103 	 * the message[] data structure.
104 	 */
105 
106 	holdsigs();
107 	if (shudclob)
108 		quit();
109 
110 	/*
111 	 * Copy the messages into /tmp
112 	 * and set pointers.
113 	 */
114 
115 	readonly = 0;
116 	if ((i = open(name, 1)) < 0)
117 		readonly++;
118 	else
119 		(void)close(i);
120 	if (shudclob) {
121 		(void)fclose(itf);
122 		(void)fclose(otf);
123 	}
124 	shudclob = 1;
125 	edit = isedit;
126 	strlcpy(prevfile, mailname, sizeof(prevfile));
127 	if (name != mailname)
128 		strlcpy(mailname, name, sizeof(mailname));
129 	mailsize = fsize(ibuf);
130 	(void)snprintf(tempname, sizeof(tempname),
131 	    "%s/mail.RxXXXXXXXXXX", tmpdir);
132 	if ((fd = mkstemp(tempname)) == -1 || (otf = fdopen(fd, "w")) == NULL)
133 		err(1, "%s", tempname);
134 	(void)fcntl(fileno(otf), F_SETFD, 1);
135 	if ((itf = fopen(tempname, "r")) == NULL)
136 		err(1, "%s", tempname);
137 	(void)fcntl(fileno(itf), F_SETFD, 1);
138 	(void)rm(tempname);
139 	setptr(ibuf);
140 	setmsize(msgCount);
141 	(void)Fclose(ibuf);
142 	relsesigs();
143 	sawcom = 0;
144 	if (!edit && msgCount == 0) {
145 nomail:
146 		fprintf(stderr, "No mail for %s\n", who);
147 		return (-1);
148 	}
149 	return (0);
150 }
151 
152 int	*msgvec;
153 int	reset_on_stop;			/* do a reset() if stopped */
154 
155 /*
156  * Interpret user commands one by one.  If standard input is not a tty,
157  * print no prompt.
158  */
159 void
160 commands()
161 {
162 	int n, eofloop = 0;
163 	char linebuf[LINESIZE];
164 
165 	if (!sourcing) {
166 		if (signal(SIGINT, SIG_IGN) != SIG_IGN)
167 			(void)signal(SIGINT, intr);
168 		if (signal(SIGHUP, SIG_IGN) != SIG_IGN)
169 			(void)signal(SIGHUP, hangup);
170 		(void)signal(SIGTSTP, stop);
171 		(void)signal(SIGTTOU, stop);
172 		(void)signal(SIGTTIN, stop);
173 	}
174 	setexit();
175 	for (;;) {
176 		/*
177 		 * Print the prompt, if needed.  Clear out
178 		 * string space, and flush the output.
179 		 */
180 		if (!sourcing && value("interactive") != NULL) {
181 			reset_on_stop = 1;
182 			printf("%s", prompt);
183 		}
184 		(void)fflush(stdout);
185 		sreset();
186 		/*
187 		 * Read a line of commands from the current input
188 		 * and handle end of file specially.
189 		 */
190 		n = 0;
191 		for (;;) {
192 			if (readline(input, &linebuf[n], LINESIZE - n) < 0) {
193 				if (n == 0)
194 					n = -1;
195 				break;
196 			}
197 			if ((n = strlen(linebuf)) == 0)
198 				break;
199 			n--;
200 			if (linebuf[n] != '\\')
201 				break;
202 			linebuf[n++] = ' ';
203 		}
204 		reset_on_stop = 0;
205 		if (n < 0) {
206 				/* eof */
207 			if (loading)
208 				break;
209 			if (sourcing) {
210 				unstack();
211 				continue;
212 			}
213 			if (value("interactive") != NULL &&
214 			    value("ignoreeof") != NULL &&
215 			    ++eofloop < 25) {
216 				printf("Use \"quit\" to quit.\n");
217 				continue;
218 			}
219 			break;
220 		}
221 		eofloop = 0;
222 		if (execute(linebuf, 0))
223 			break;
224 	}
225 }
226 
227 /*
228  * Execute a single command.
229  * Command functions return 0 for success, 1 for error, and -1
230  * for abort.  A 1 or -1 aborts a load or source.  A -1 aborts
231  * the interactive command loop.
232  * Contxt is non-zero if called while composing mail.
233  */
234 int
235 execute(linebuf, contxt)
236 	char linebuf[];
237 	int contxt;
238 {
239 	char word[LINESIZE];
240 	char *arglist[MAXARGC];
241 	const struct cmd *com;
242 	char *cp, *cp2;
243 	int c, muvec[2];
244 	int e = 1;
245 
246 	/*
247 	 * Strip the white space away from the beginning
248 	 * of the command, then scan out a word, which
249 	 * consists of anything except digits and white space.
250 	 *
251 	 * Handle ! escapes differently to get the correct
252 	 * lexical conventions.
253 	 */
254 
255 	for (cp = linebuf; isspace(*cp); cp++)
256 		;
257 	if (*cp == '!') {
258 		if (sourcing) {
259 			printf("Can't \"!\" while sourcing\n");
260 			goto out;
261 		}
262 		shell(cp+1);
263 		return (0);
264 	}
265 	cp2 = word;
266 	while (*cp != '\0' && strchr(" \t0123456789$^.:/-+*'\"", *cp) == NULL)
267 		*cp2++ = *cp++;
268 	*cp2 = '\0';
269 
270 	/*
271 	 * Look up the command; if not found, bitch.
272 	 * Normally, a blank command would map to the
273 	 * first command in the table; while sourcing,
274 	 * however, we ignore blank lines to eliminate
275 	 * confusion.
276 	 */
277 
278 	if (sourcing && *word == '\0')
279 		return (0);
280 	com = lex(word);
281 	if (com == NULL) {
282 		printf("Unknown command: \"%s\"\n", word);
283 		goto out;
284 	}
285 
286 	/*
287 	 * See if we should execute the command -- if a conditional
288 	 * we always execute it, otherwise, check the state of cond.
289 	 */
290 
291 	if ((com->c_argtype & F) == 0)
292 		if ((cond == CRCV && !rcvmode) || (cond == CSEND && rcvmode))
293 			return (0);
294 
295 	/*
296 	 * Process the arguments to the command, depending
297 	 * on the type he expects.  Default to an error.
298 	 * If we are sourcing an interactive command, it's
299 	 * an error.
300 	 */
301 
302 	if (!rcvmode && (com->c_argtype & M) == 0) {
303 		printf("May not execute \"%s\" while sending\n",
304 		    com->c_name);
305 		goto out;
306 	}
307 	if (sourcing && com->c_argtype & I) {
308 		printf("May not execute \"%s\" while sourcing\n",
309 		    com->c_name);
310 		goto out;
311 	}
312 	if (readonly && com->c_argtype & W) {
313 		printf("May not execute \"%s\" -- message file is read only\n",
314 		   com->c_name);
315 		goto out;
316 	}
317 	if (contxt && com->c_argtype & R) {
318 		printf("Cannot recursively invoke \"%s\"\n", com->c_name);
319 		goto out;
320 	}
321 	switch (com->c_argtype & ~(F|P|I|M|T|W|R)) {
322 	case MSGLIST:
323 		/*
324 		 * A message list defaulting to nearest forward
325 		 * legal message.
326 		 */
327 		if (msgvec == 0) {
328 			printf("Illegal use of \"message list\"\n");
329 			break;
330 		}
331 		if ((c = getmsglist(cp, msgvec, com->c_msgflag)) < 0)
332 			break;
333 		if (c  == 0) {
334 			*msgvec = first(com->c_msgflag, com->c_msgmask);
335 			msgvec[1] = 0;
336 		}
337 		if (*msgvec == 0) {
338 			printf("No applicable messages\n");
339 			break;
340 		}
341 		e = (*com->c_func)(msgvec);
342 		break;
343 
344 	case NDMLIST:
345 		/*
346 		 * A message list with no defaults, but no error
347 		 * if none exist.
348 		 */
349 		if (msgvec == 0) {
350 			printf("Illegal use of \"message list\"\n");
351 			break;
352 		}
353 		if (getmsglist(cp, msgvec, com->c_msgflag) < 0)
354 			break;
355 		e = (*com->c_func)(msgvec);
356 		break;
357 
358 	case STRLIST:
359 		/*
360 		 * Just the straight string, with
361 		 * leading blanks removed.
362 		 */
363 		while (isspace(*cp))
364 			cp++;
365 		e = (*com->c_func)(cp);
366 		break;
367 
368 	case RAWLIST:
369 		/*
370 		 * A vector of strings, in shell style.
371 		 */
372 		if ((c = getrawlist(cp, arglist,
373 		    sizeof(arglist) / sizeof(*arglist))) < 0)
374 			break;
375 		if (c < com->c_minargs) {
376 			printf("%s requires at least %d arg(s)\n",
377 			    com->c_name, com->c_minargs);
378 			break;
379 		}
380 		if (c > com->c_maxargs) {
381 			printf("%s takes no more than %d arg(s)\n",
382 			    com->c_name, com->c_maxargs);
383 			break;
384 		}
385 		e = (*com->c_func)(arglist);
386 		break;
387 
388 	case NOLIST:
389 		/*
390 		 * Just the constant zero, for exiting,
391 		 * eg.
392 		 */
393 		e = (*com->c_func)(0);
394 		break;
395 
396 	default:
397 		errx(1, "Unknown argtype");
398 	}
399 
400 out:
401 	/*
402 	 * Exit the current source file on
403 	 * error.
404 	 */
405 	if (e) {
406 		if (e < 0)
407 			return (1);
408 		if (loading)
409 			return (1);
410 		if (sourcing)
411 			unstack();
412 		return (0);
413 	}
414 	if (value("autoprint") != NULL && com->c_argtype & P)
415 		if ((dot->m_flag & MDELETED) == 0) {
416 			muvec[0] = dot - &message[0] + 1;
417 			muvec[1] = 0;
418 			type(muvec);
419 		}
420 	if (!sourcing && (com->c_argtype & T) == 0)
421 		sawcom = 1;
422 	return (0);
423 }
424 
425 /*
426  * Set the size of the message vector used to construct argument
427  * lists to message list functions.
428  */
429 void
430 setmsize(sz)
431 	int sz;
432 {
433 
434 	if (msgvec != 0)
435 		(void)free(msgvec);
436 	msgvec = calloc((unsigned)(sz + 1), sizeof(*msgvec));
437 }
438 
439 /*
440  * Find the correct command in the command table corresponding
441  * to the passed command "word"
442  */
443 
444 __const struct cmd *
445 lex(word)
446 	char word[];
447 {
448 	const struct cmd *cp;
449 
450 	/*
451 	 * ignore trailing chars after `#'
452 	 *
453 	 * lines with beginning `#' are comments
454 	 * spaces before `#' are ignored in execute()
455 	 */
456 
457 	if (*word == '#')
458 	    *(word+1) = '\0';
459 
460 
461 	for (cp = &cmdtab[0]; cp->c_name != NULL; cp++)
462 		if (isprefix(word, cp->c_name))
463 			return (cp);
464 	return (NULL);
465 }
466 
467 /*
468  * Determine if as1 is a valid prefix of as2.
469  * Return true if yep.
470  */
471 int
472 isprefix(as1, as2)
473 	const char *as1, *as2;
474 {
475 	const char *s1, *s2;
476 
477 	s1 = as1;
478 	s2 = as2;
479 	while (*s1++ == *s2)
480 		if (*s2++ == '\0')
481 			return (1);
482 	return (*--s1 == '\0');
483 }
484 
485 /*
486  * The following gets called on receipt of an interrupt.  This is
487  * to abort printout of a command, mainly.
488  * Dispatching here when command() is inactive crashes rcv.
489  * Close all open files except 0, 1, 2, and the temporary.
490  * Also, unstack all source files.
491  */
492 
493 int	inithdr;			/* am printing startup headers */
494 
495 /*ARGSUSED*/
496 void
497 intr(s)
498 	int s;
499 {
500 
501 	noreset = 0;
502 	if (!inithdr)
503 		sawcom++;
504 	inithdr = 0;
505 	while (sourcing)
506 		unstack();
507 
508 	close_all_files();
509 
510 	if (image >= 0) {
511 		(void)close(image);
512 		image = -1;
513 	}
514 	fprintf(stderr, "Interrupt\n");
515 	reset(0);
516 }
517 
518 /*
519  * When we wake up after ^Z, reprint the prompt.
520  */
521 void
522 stop(s)
523 	int s;
524 {
525 	sig_t old_action = signal(s, SIG_DFL);
526 
527 	(void)sigsetmask(sigblock(0) & ~sigmask(s));
528 	(void)kill(0, s);
529 	(void)sigblock(sigmask(s));
530 	(void)signal(s, old_action);
531 	if (reset_on_stop) {
532 		reset_on_stop = 0;
533 		reset(0);
534 	}
535 }
536 
537 /*
538  * Branch here on hangup signal and simulate "exit".
539  */
540 /*ARGSUSED*/
541 void
542 hangup(s)
543 	int s;
544 {
545 
546 	/* nothing to do? */
547 	exit(1);
548 }
549 
550 /*
551  * Announce the presence of the current Mail version,
552  * give the message count, and print a header listing.
553  */
554 void
555 announce()
556 {
557 	int vec[2], mdot;
558 
559 	mdot = newfileinfo();
560 	vec[0] = mdot;
561 	vec[1] = 0;
562 	dot = &message[mdot - 1];
563 	if (msgCount > 0 && value("noheader") == NULL) {
564 		inithdr++;
565 		headers(vec);
566 		inithdr = 0;
567 	}
568 }
569 
570 /*
571  * Announce information about the file we are editing.
572  * Return a likely place to set dot.
573  */
574 int
575 newfileinfo()
576 {
577 	struct message *mp;
578 	int u, n, mdot, d, s;
579 	char fname[PATHSIZE+1], zname[PATHSIZE+1], *ename;
580 
581 	for (mp = &message[0]; mp < &message[msgCount]; mp++)
582 		if (mp->m_flag & MNEW)
583 			break;
584 	if (mp >= &message[msgCount])
585 		for (mp = &message[0]; mp < &message[msgCount]; mp++)
586 			if ((mp->m_flag & MREAD) == 0)
587 				break;
588 	if (mp < &message[msgCount])
589 		mdot = mp - &message[0] + 1;
590 	else
591 		mdot = 1;
592 	s = d = 0;
593 	for (mp = &message[0], n = 0, u = 0; mp < &message[msgCount]; mp++) {
594 		if (mp->m_flag & MNEW)
595 			n++;
596 		if ((mp->m_flag & MREAD) == 0)
597 			u++;
598 		if (mp->m_flag & MDELETED)
599 			d++;
600 		if (mp->m_flag & MSAVED)
601 			s++;
602 	}
603 	ename = mailname;
604 	if (getfold(fname, sizeof(fname) - 1) >= 0) {
605 		strcat(fname, "/");
606 		if (strncmp(fname, mailname, strlen(fname)) == 0) {
607 			(void)snprintf(zname, sizeof(zname), "+%s",
608 			    mailname + strlen(fname));
609 			ename = zname;
610 		}
611 	}
612 	printf("\"%s\": ", ename);
613 	if (msgCount == 1)
614 		printf("1 message");
615 	else
616 		printf("%d messages", msgCount);
617 	if (n > 0)
618 		printf(" %d new", n);
619 	if (u-n > 0)
620 		printf(" %d unread", u);
621 	if (d > 0)
622 		printf(" %d deleted", d);
623 	if (s > 0)
624 		printf(" %d saved", s);
625 	if (readonly)
626 		printf(" [Read only]");
627 	printf("\n");
628 	return (mdot);
629 }
630 
631 /*
632  * Print the current version number.
633  */
634 
635 /*ARGSUSED*/
636 int
637 pversion(e)
638 	int e;
639 {
640 
641 	printf("Version %s\n", version);
642 	return (0);
643 }
644 
645 /*
646  * Load a file of user definitions.
647  */
648 void
649 load(name)
650 	char *name;
651 {
652 	FILE *in, *oldin;
653 
654 	if ((in = Fopen(name, "r")) == NULL)
655 		return;
656 	oldin = input;
657 	input = in;
658 	loading = 1;
659 	sourcing = 1;
660 	commands();
661 	loading = 0;
662 	sourcing = 0;
663 	input = oldin;
664 	(void)Fclose(in);
665 }
666