xref: /netbsd-src/usr.bin/mail/lex.c (revision ce0bb6e8d2e560ecacbe865a848624f94498063b)
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 static char sccsid[] = "from: @(#)lex.c	8.1 (Berkeley) 6/6/93";
36 static char rcsid[] = "$Id: lex.c,v 1.5 1994/11/28 20:03:33 jtc Exp $";
37 #endif /* not lint */
38 
39 #include "rcv.h"
40 #include <errno.h>
41 #include <fcntl.h>
42 #include "extern.h"
43 
44 /*
45  * Mail -- a mail program
46  *
47  * Lexical processing of commands.
48  */
49 
50 char	*prompt = "& ";
51 
52 /*
53  * Set up editing on the given file name.
54  * If the first character of name is %, we are considered to be
55  * editing the file, otherwise we are reading our mail which has
56  * signficance for mbox and so forth.
57  */
58 int
59 setfile(name)
60 	char *name;
61 {
62 	FILE *ibuf;
63 	int i;
64 	struct stat stb;
65 	char isedit = *name != '%';
66 	char *who = name[1] ? name + 1 : myname;
67 	static int shudclob;
68 	extern char *tempMesg;
69 	extern int errno;
70 
71 	if ((name = expand(name)) == NOSTR)
72 		return -1;
73 
74 	if ((ibuf = Fopen(name, "r")) == NULL) {
75 		if (!isedit && errno == ENOENT)
76 			goto nomail;
77 		perror(name);
78 		return(-1);
79 	}
80 
81 	if (fstat(fileno(ibuf), &stb) < 0) {
82 		perror("fstat");
83 		Fclose(ibuf);
84 		return (-1);
85 	}
86 
87 	switch (stb.st_mode & S_IFMT) {
88 	case S_IFDIR:
89 		Fclose(ibuf);
90 		errno = EISDIR;
91 		perror(name);
92 		return (-1);
93 
94 	case S_IFREG:
95 		break;
96 
97 	default:
98 		Fclose(ibuf);
99 		errno = EINVAL;
100 		perror(name);
101 		return (-1);
102 	}
103 
104 	/*
105 	 * Looks like all will be well.  We must now relinquish our
106 	 * hold on the current set of stuff.  Must hold signals
107 	 * while we are reading the new file, else we will ruin
108 	 * the message[] data structure.
109 	 */
110 
111 	holdsigs();
112 	if (shudclob)
113 		quit();
114 
115 	/*
116 	 * Copy the messages into /tmp
117 	 * and set pointers.
118 	 */
119 
120 	readonly = 0;
121 	if ((i = open(name, 1)) < 0)
122 		readonly++;
123 	else
124 		close(i);
125 	if (shudclob) {
126 		fclose(itf);
127 		fclose(otf);
128 	}
129 	shudclob = 1;
130 	edit = isedit;
131 	strcpy(prevfile, mailname);
132 	if (name != mailname)
133 		strcpy(mailname, name);
134 	mailsize = fsize(ibuf);
135 	if ((otf = fopen(tempMesg, "w")) == NULL) {
136 		perror(tempMesg);
137 		exit(1);
138 	}
139 	(void) fcntl(fileno(otf), F_SETFD, 1);
140 	if ((itf = fopen(tempMesg, "r")) == NULL) {
141 		perror(tempMesg);
142 		exit(1);
143 	}
144 	(void) fcntl(fileno(itf), F_SETFD, 1);
145 	rm(tempMesg);
146 	setptr(ibuf);
147 	setmsize(msgCount);
148 	Fclose(ibuf);
149 	relsesigs();
150 	sawcom = 0;
151 	if (!edit && msgCount == 0) {
152 nomail:
153 		fprintf(stderr, "No mail for %s\n", who);
154 		return -1;
155 	}
156 	return(0);
157 }
158 
159 int	*msgvec;
160 int	reset_on_stop;			/* do a reset() if stopped */
161 
162 /*
163  * Interpret user commands one by one.  If standard input is not a tty,
164  * print no prompt.
165  */
166 void
167 commands()
168 {
169 	int eofloop = 0;
170 	register int n;
171 	char linebuf[LINESIZE];
172 	void intr(), stop(), hangup();
173 
174 	if (!sourcing) {
175 		if (signal(SIGINT, SIG_IGN) != SIG_IGN)
176 			signal(SIGINT, intr);
177 		if (signal(SIGHUP, SIG_IGN) != SIG_IGN)
178 			signal(SIGHUP, hangup);
179 		signal(SIGTSTP, stop);
180 		signal(SIGTTOU, stop);
181 		signal(SIGTTIN, stop);
182 	}
183 	setexit();
184 	for (;;) {
185 		/*
186 		 * Print the prompt, if needed.  Clear out
187 		 * string space, and flush the output.
188 		 */
189 		if (!sourcing && value("interactive") != NOSTR) {
190 			reset_on_stop = 1;
191 			printf(prompt);
192 		}
193 		fflush(stdout);
194 		sreset();
195 		/*
196 		 * Read a line of commands from the current input
197 		 * and handle end of file specially.
198 		 */
199 		n = 0;
200 		for (;;) {
201 			if (readline(input, &linebuf[n], LINESIZE - n) < 0) {
202 				if (n == 0)
203 					n = -1;
204 				break;
205 			}
206 			if ((n = strlen(linebuf)) == 0)
207 				break;
208 			n--;
209 			if (linebuf[n] != '\\')
210 				break;
211 			linebuf[n++] = ' ';
212 		}
213 		reset_on_stop = 0;
214 		if (n < 0) {
215 				/* eof */
216 			if (loading)
217 				break;
218 			if (sourcing) {
219 				unstack();
220 				continue;
221 			}
222 			if (value("interactive") != NOSTR &&
223 			    value("ignoreeof") != NOSTR &&
224 			    ++eofloop < 25) {
225 				printf("Use \"quit\" to quit.\n");
226 				continue;
227 			}
228 			break;
229 		}
230 		eofloop = 0;
231 		if (execute(linebuf, 0))
232 			break;
233 	}
234 }
235 
236 /*
237  * Execute a single command.
238  * Command functions return 0 for success, 1 for error, and -1
239  * for abort.  A 1 or -1 aborts a load or source.  A -1 aborts
240  * the interactive command loop.
241  * Contxt is non-zero if called while composing mail.
242  */
243 int
244 execute(linebuf, contxt)
245 	char linebuf[];
246 	int contxt;
247 {
248 	char word[LINESIZE];
249 	char *arglist[MAXARGC];
250 	struct cmd *com;
251 	register char *cp, *cp2;
252 	register int c;
253 	int muvec[2];
254 	int e = 1;
255 
256 	/*
257 	 * Strip the white space away from the beginning
258 	 * of the command, then scan out a word, which
259 	 * consists of anything except digits and white space.
260 	 *
261 	 * Handle ! escapes differently to get the correct
262 	 * lexical conventions.
263 	 */
264 
265 	for (cp = linebuf; isspace(*cp); cp++)
266 		;
267 	if (*cp == '!') {
268 		if (sourcing) {
269 			printf("Can't \"!\" while sourcing\n");
270 			goto out;
271 		}
272 		shell(cp+1);
273 		return(0);
274 	}
275 	cp2 = word;
276 	while (*cp && index(" \t0123456789$^.:/-+*'\"", *cp) == NOSTR)
277 		*cp2++ = *cp++;
278 	*cp2 = '\0';
279 
280 	/*
281 	 * Look up the command; if not found, bitch.
282 	 * Normally, a blank command would map to the
283 	 * first command in the table; while sourcing,
284 	 * however, we ignore blank lines to eliminate
285 	 * confusion.
286 	 */
287 
288 	if (sourcing && *word == '\0')
289 		return(0);
290 	com = lex(word);
291 	if (com == NONE) {
292 		printf("Unknown command: \"%s\"\n", word);
293 		goto out;
294 	}
295 
296 	/*
297 	 * See if we should execute the command -- if a conditional
298 	 * we always execute it, otherwise, check the state of cond.
299 	 */
300 
301 	if ((com->c_argtype & F) == 0)
302 		if (cond == CRCV && !rcvmode || cond == CSEND && rcvmode)
303 			return(0);
304 
305 	/*
306 	 * Process the arguments to the command, depending
307 	 * on the type he expects.  Default to an error.
308 	 * If we are sourcing an interactive command, it's
309 	 * an error.
310 	 */
311 
312 	if (!rcvmode && (com->c_argtype & M) == 0) {
313 		printf("May not execute \"%s\" while sending\n",
314 		    com->c_name);
315 		goto out;
316 	}
317 	if (sourcing && com->c_argtype & I) {
318 		printf("May not execute \"%s\" while sourcing\n",
319 		    com->c_name);
320 		goto out;
321 	}
322 	if (readonly && com->c_argtype & W) {
323 		printf("May not execute \"%s\" -- message file is read only\n",
324 		   com->c_name);
325 		goto out;
326 	}
327 	if (contxt && com->c_argtype & R) {
328 		printf("Cannot recursively invoke \"%s\"\n", com->c_name);
329 		goto out;
330 	}
331 	switch (com->c_argtype & ~(F|P|I|M|T|W|R)) {
332 	case MSGLIST:
333 		/*
334 		 * A message list defaulting to nearest forward
335 		 * legal message.
336 		 */
337 		if (msgvec == 0) {
338 			printf("Illegal use of \"message list\"\n");
339 			break;
340 		}
341 		if ((c = getmsglist(cp, msgvec, com->c_msgflag)) < 0)
342 			break;
343 		if (c  == 0) {
344 			*msgvec = first(com->c_msgflag,
345 				com->c_msgmask);
346 			msgvec[1] = NULL;
347 		}
348 		if (*msgvec == NULL) {
349 			printf("No applicable messages\n");
350 			break;
351 		}
352 		e = (*com->c_func)(msgvec);
353 		break;
354 
355 	case NDMLIST:
356 		/*
357 		 * A message list with no defaults, but no error
358 		 * if none exist.
359 		 */
360 		if (msgvec == 0) {
361 			printf("Illegal use of \"message list\"\n");
362 			break;
363 		}
364 		if (getmsglist(cp, msgvec, com->c_msgflag) < 0)
365 			break;
366 		e = (*com->c_func)(msgvec);
367 		break;
368 
369 	case STRLIST:
370 		/*
371 		 * Just the straight string, with
372 		 * leading blanks removed.
373 		 */
374 		while (isspace(*cp))
375 			cp++;
376 		e = (*com->c_func)(cp);
377 		break;
378 
379 	case RAWLIST:
380 		/*
381 		 * A vector of strings, in shell style.
382 		 */
383 		if ((c = getrawlist(cp, arglist,
384 				sizeof arglist / sizeof *arglist)) < 0)
385 			break;
386 		if (c < com->c_minargs) {
387 			printf("%s requires at least %d arg(s)\n",
388 				com->c_name, com->c_minargs);
389 			break;
390 		}
391 		if (c > com->c_maxargs) {
392 			printf("%s takes no more than %d arg(s)\n",
393 				com->c_name, com->c_maxargs);
394 			break;
395 		}
396 		e = (*com->c_func)(arglist);
397 		break;
398 
399 	case NOLIST:
400 		/*
401 		 * Just the constant zero, for exiting,
402 		 * eg.
403 		 */
404 		e = (*com->c_func)(0);
405 		break;
406 
407 	default:
408 		panic("Unknown argtype");
409 	}
410 
411 out:
412 	/*
413 	 * Exit the current source file on
414 	 * error.
415 	 */
416 	if (e) {
417 		if (e < 0)
418 			return 1;
419 		if (loading)
420 			return 1;
421 		if (sourcing)
422 			unstack();
423 		return 0;
424 	}
425 	if (value("autoprint") != NOSTR && com->c_argtype & P)
426 		if ((dot->m_flag & MDELETED) == 0) {
427 			muvec[0] = dot - &message[0] + 1;
428 			muvec[1] = 0;
429 			type(muvec);
430 		}
431 	if (!sourcing && (com->c_argtype & T) == 0)
432 		sawcom = 1;
433 	return(0);
434 }
435 
436 /*
437  * Set the size of the message vector used to construct argument
438  * lists to message list functions.
439  */
440 void
441 setmsize(sz)
442 	int sz;
443 {
444 
445 	if (msgvec != 0)
446 		free((char *) msgvec);
447 	msgvec = (int *) calloc((unsigned) (sz + 1), sizeof *msgvec);
448 }
449 
450 /*
451  * Find the correct command in the command table corresponding
452  * to the passed command "word"
453  */
454 
455 struct cmd *
456 lex(word)
457 	char word[];
458 {
459 	register struct cmd *cp;
460 	extern struct cmd cmdtab[];
461 
462 	for (cp = &cmdtab[0]; cp->c_name != NOSTR; cp++)
463 		if (isprefix(word, cp->c_name))
464 			return(cp);
465 	return(NONE);
466 }
467 
468 /*
469  * Determine if as1 is a valid prefix of as2.
470  * Return true if yep.
471  */
472 int
473 isprefix(as1, as2)
474 	char *as1, *as2;
475 {
476 	register char *s1, *s2;
477 
478 	s1 = as1;
479 	s2 = as2;
480 	while (*s1++ == *s2)
481 		if (*s2++ == '\0')
482 			return(1);
483 	return(*--s1 == '\0');
484 }
485 
486 /*
487  * The following gets called on receipt of an interrupt.  This is
488  * to abort printout of a command, mainly.
489  * Dispatching here when command() is inactive crashes rcv.
490  * Close all open files except 0, 1, 2, and the temporary.
491  * Also, unstack all source files.
492  */
493 
494 int	inithdr;			/* am printing startup headers */
495 
496 /*ARGSUSED*/
497 void
498 intr(s)
499 	int s;
500 {
501 
502 	noreset = 0;
503 	if (!inithdr)
504 		sawcom++;
505 	inithdr = 0;
506 	while (sourcing)
507 		unstack();
508 
509 	close_all_files();
510 
511 	if (image >= 0) {
512 		close(image);
513 		image = -1;
514 	}
515 	fprintf(stderr, "Interrupt\n");
516 	reset(0);
517 }
518 
519 /*
520  * When we wake up after ^Z, reprint the prompt.
521  */
522 void
523 stop(s)
524 	int s;
525 {
526 	sig_t old_action = signal(s, SIG_DFL);
527 
528 	sigsetmask(sigblock(0) & ~sigmask(s));
529 	kill(0, s);
530 	sigblock(sigmask(s));
531 	signal(s, old_action);
532 	if (reset_on_stop) {
533 		reset_on_stop = 0;
534 		reset(0);
535 	}
536 }
537 
538 /*
539  * Branch here on hangup signal and simulate "exit".
540  */
541 /*ARGSUSED*/
542 void
543 hangup(s)
544 	int s;
545 {
546 
547 	/* nothing to do? */
548 	exit(1);
549 }
550 
551 /*
552  * Announce the presence of the current Mail version,
553  * give the message count, and print a header listing.
554  */
555 void
556 announce()
557 {
558 	int vec[2], mdot;
559 
560 	mdot = newfileinfo();
561 	vec[0] = mdot;
562 	vec[1] = 0;
563 	dot = &message[mdot - 1];
564 	if (msgCount > 0 && value("noheader") == NOSTR) {
565 		inithdr++;
566 		headers(vec);
567 		inithdr = 0;
568 	}
569 }
570 
571 /*
572  * Announce information about the file we are editing.
573  * Return a likely place to set dot.
574  */
575 int
576 newfileinfo()
577 {
578 	register struct message *mp;
579 	register int u, n, mdot, d, s;
580 	char fname[BUFSIZ], zname[BUFSIZ], *ename;
581 
582 	for (mp = &message[0]; mp < &message[msgCount]; mp++)
583 		if (mp->m_flag & MNEW)
584 			break;
585 	if (mp >= &message[msgCount])
586 		for (mp = &message[0]; mp < &message[msgCount]; mp++)
587 			if ((mp->m_flag & MREAD) == 0)
588 				break;
589 	if (mp < &message[msgCount])
590 		mdot = mp - &message[0] + 1;
591 	else
592 		mdot = 1;
593 	s = d = 0;
594 	for (mp = &message[0], n = 0, u = 0; mp < &message[msgCount]; mp++) {
595 		if (mp->m_flag & MNEW)
596 			n++;
597 		if ((mp->m_flag & MREAD) == 0)
598 			u++;
599 		if (mp->m_flag & MDELETED)
600 			d++;
601 		if (mp->m_flag & MSAVED)
602 			s++;
603 	}
604 	ename = mailname;
605 	if (getfold(fname) >= 0) {
606 		strcat(fname, "/");
607 		if (strncmp(fname, mailname, strlen(fname)) == 0) {
608 			sprintf(zname, "+%s", 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 	extern char *version;
641 
642 	printf("Version %s\n", version);
643 	return(0);
644 }
645 
646 /*
647  * Load a file of user definitions.
648  */
649 void
650 load(name)
651 	char *name;
652 {
653 	register FILE *in, *oldin;
654 
655 	if ((in = Fopen(name, "r")) == NULL)
656 		return;
657 	oldin = input;
658 	input = in;
659 	loading = 1;
660 	sourcing = 1;
661 	commands();
662 	loading = 0;
663 	sourcing = 0;
664 	input = oldin;
665 	Fclose(in);
666 }
667