lex.c revision 173439 
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
36static char sccsid[] = "@(#)lex.c	8.2 (Berkeley) 4/20/95";
37#endif
38#endif /* not lint */
39#include <sys/cdefs.h>
40__FBSDID("$FreeBSD: head/usr.bin/mail/lex.c 173439 2007-11-08 11:13:03Z dds $");
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
53static const char	*prompt = "& ";
54
55extern const struct cmd cmdtab[];
56extern 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 * If the -e option is being passed to mail, this function has a
65 * tri-state return code: -1 on error, 0 on no mail, 1 if there is
66 * mail.
67 */
68int
69setfile(name)
70	char *name;
71{
72	FILE *ibuf;
73	int checkmode, i, fd;
74	struct stat stb;
75	char isedit = *name != '%' || getuserid(myname) != getuid();
76	char *who = name[1] ? name + 1 : myname;
77	char tempname[PATHSIZE];
78	static int shudclob;
79
80	checkmode = value("checkmode") != NULL;
81	if ((name = expand(name)) == NULL)
82		return (-1);
83
84	if ((ibuf = Fopen(name, "r")) == NULL) {
85		if (!isedit && errno == ENOENT)
86			goto nomail;
87		warn("%s", name);
88		return (-1);
89	}
90
91	if (fstat(fileno(ibuf), &stb) < 0) {
92		warn("fstat");
93		(void)Fclose(ibuf);
94		return (-1);
95	}
96
97	if (S_ISDIR(stb.st_mode) || !S_ISREG(stb.st_mode)) {
98		(void)Fclose(ibuf);
99		errno = S_ISDIR(stb.st_mode) ? EISDIR : EINVAL;
100		warn("%s", 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		(void)close(i);
125	if (shudclob) {
126		(void)fclose(itf);
127		(void)fclose(otf);
128	}
129	shudclob = 1;
130	edit = isedit;
131	strlcpy(prevfile, mailname, sizeof(prevfile));
132	if (name != mailname)
133		strlcpy(mailname, name, sizeof(mailname));
134	mailsize = fsize(ibuf);
135	(void)snprintf(tempname, sizeof(tempname),
136	    "%s/mail.RxXXXXXXXXXX", tmpdir);
137	if ((fd = mkstemp(tempname)) == -1 || (otf = fdopen(fd, "w")) == NULL)
138		err(1, "%s", tempname);
139	(void)fcntl(fileno(otf), F_SETFD, 1);
140	if ((itf = fopen(tempname, "r")) == NULL)
141		err(1, "%s", tempname);
142	(void)fcntl(fileno(itf), F_SETFD, 1);
143	(void)rm(tempname);
144	setptr(ibuf, 0);
145	setmsize(msgCount);
146	/*
147	 * New mail may have arrived while we were reading
148	 * the mail file, so reset mailsize to be where
149	 * we really are in the file...
150	 */
151	mailsize = ftello(ibuf);
152	(void)Fclose(ibuf);
153	relsesigs();
154	sawcom = 0;
155
156	if ((checkmode || !edit) && msgCount == 0) {
157nomail:
158		if (!checkmode) {
159			fprintf(stderr, "No mail for %s\n", who);
160			return (-1);
161		} else
162			return (0);
163	}
164	return (checkmode ? 1 : 0);
165}
166
167/*
168 * Incorporate any new mail that has arrived since we first
169 * started reading mail.
170 */
171int
172incfile()
173{
174	off_t newsize;
175	int omsgCount = msgCount;
176	FILE *ibuf;
177
178	ibuf = Fopen(mailname, "r");
179	if (ibuf == NULL)
180		return (-1);
181	holdsigs();
182	newsize = fsize(ibuf);
183	if (newsize == 0)
184		return (-1);		/* mail box is now empty??? */
185	if (newsize < mailsize)
186		return (-1);		/* mail box has shrunk??? */
187	if (newsize == mailsize)
188		return (0);		/* no new mail */
189	setptr(ibuf, mailsize);
190	setmsize(msgCount);
191	mailsize = ftello(ibuf);
192	(void)Fclose(ibuf);
193	relsesigs();
194	return (msgCount - omsgCount);
195}
196
197static int	*msgvec;
198static int	reset_on_stop;		/* do a reset() if stopped */
199
200/*
201 * Interpret user commands one by one.  If standard input is not a tty,
202 * print no prompt.
203 */
204void
205commands()
206{
207	int n, eofloop = 0;
208	char linebuf[LINESIZE];
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();
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				printf("New mail has arrived.\n");
228			reset_on_stop = 1;
229			printf("%s", prompt);
230		}
231		(void)fflush(stdout);
232		sreset();
233		/*
234		 * Read a line of commands from the current input
235		 * and handle end of file specially.
236		 */
237		n = 0;
238		for (;;) {
239			if (readline(input, &linebuf[n], LINESIZE - n) < 0) {
240				if (n == 0)
241					n = -1;
242				break;
243			}
244			if ((n = strlen(linebuf)) == 0)
245				break;
246			n--;
247			if (linebuf[n] != '\\')
248				break;
249			linebuf[n++] = ' ';
250		}
251		reset_on_stop = 0;
252		if (n < 0) {
253				/* eof */
254			if (loading)
255				break;
256			if (sourcing) {
257				unstack();
258				continue;
259			}
260			if (value("interactive") != NULL &&
261			    value("ignoreeof") != NULL &&
262			    ++eofloop < 25) {
263				printf("Use \"quit\" to quit.\n");
264				continue;
265			}
266			break;
267		}
268		eofloop = 0;
269		if (execute(linebuf, 0))
270			break;
271	}
272}
273
274/*
275 * Execute a single command.
276 * Command functions return 0 for success, 1 for error, and -1
277 * for abort.  A 1 or -1 aborts a load or source.  A -1 aborts
278 * the interactive command loop.
279 * Contxt is non-zero if called while composing mail.
280 */
281int
282execute(linebuf, contxt)
283	char linebuf[];
284	int contxt;
285{
286	char word[LINESIZE];
287	char *arglist[MAXARGC];
288	const struct cmd *com;
289	char *cp, *cp2;
290	int c, muvec[2];
291	int e = 1;
292
293	/*
294	 * Strip the white space away from the beginning
295	 * of the command, then scan out a word, which
296	 * consists of anything except digits and white space.
297	 *
298	 * Handle ! escapes differently to get the correct
299	 * lexical conventions.
300	 */
301
302	for (cp = linebuf; isspace((unsigned char)*cp); cp++)
303		;
304	if (*cp == '!') {
305		if (sourcing) {
306			printf("Can't \"!\" while sourcing\n");
307			goto out;
308		}
309		shell(cp+1);
310		return (0);
311	}
312	cp2 = word;
313	while (*cp != '\0' && strchr(" \t0123456789$^.:/-+*'\"", *cp) == NULL)
314		*cp2++ = *cp++;
315	*cp2 = '\0';
316
317	/*
318	 * Look up the command; if not found, bitch.
319	 * Normally, a blank command would map to the
320	 * first command in the table; while sourcing,
321	 * however, we ignore blank lines to eliminate
322	 * confusion.
323	 */
324
325	if (sourcing && *word == '\0')
326		return (0);
327	com = lex(word);
328	if (com == NULL) {
329		printf("Unknown command: \"%s\"\n", word);
330		goto out;
331	}
332
333	/*
334	 * See if we should execute the command -- if a conditional
335	 * we always execute it, otherwise, check the state of cond.
336	 */
337
338	if ((com->c_argtype & F) == 0)
339		if ((cond == CRCV && !rcvmode) || (cond == CSEND && rcvmode))
340			return (0);
341
342	/*
343	 * Process the arguments to the command, depending
344	 * on the type he expects.  Default to an error.
345	 * If we are sourcing an interactive command, it's
346	 * an error.
347	 */
348
349	if (!rcvmode && (com->c_argtype & M) == 0) {
350		printf("May not execute \"%s\" while sending\n",
351		    com->c_name);
352		goto out;
353	}
354	if (sourcing && com->c_argtype & I) {
355		printf("May not execute \"%s\" while sourcing\n",
356		    com->c_name);
357		goto out;
358	}
359	if (readonly && com->c_argtype & W) {
360		printf("May not execute \"%s\" -- message file is read only\n",
361		   com->c_name);
362		goto out;
363	}
364	if (contxt && com->c_argtype & R) {
365		printf("Cannot recursively invoke \"%s\"\n", com->c_name);
366		goto out;
367	}
368	switch (com->c_argtype & ~(F|P|I|M|T|W|R)) {
369	case MSGLIST:
370		/*
371		 * A message list defaulting to nearest forward
372		 * legal message.
373		 */
374		if (msgvec == 0) {
375			printf("Illegal use of \"message list\"\n");
376			break;
377		}
378		if ((c = getmsglist(cp, msgvec, com->c_msgflag)) < 0)
379			break;
380		if (c  == 0) {
381			*msgvec = first(com->c_msgflag, com->c_msgmask);
382			msgvec[1] = 0;
383		}
384		if (*msgvec == 0) {
385			printf("No applicable messages\n");
386			break;
387		}
388		e = (*com->c_func)(msgvec);
389		break;
390
391	case NDMLIST:
392		/*
393		 * A message list with no defaults, but no error
394		 * if none exist.
395		 */
396		if (msgvec == 0) {
397			printf("Illegal use of \"message list\"\n");
398			break;
399		}
400		if (getmsglist(cp, msgvec, com->c_msgflag) < 0)
401			break;
402		e = (*com->c_func)(msgvec);
403		break;
404
405	case STRLIST:
406		/*
407		 * Just the straight string, with
408		 * leading blanks removed.
409		 */
410		while (isspace((unsigned char)*cp))
411			cp++;
412		e = (*com->c_func)(cp);
413		break;
414
415	case RAWLIST:
416		/*
417		 * A vector of strings, in shell style.
418		 */
419		if ((c = getrawlist(cp, arglist,
420		    sizeof(arglist) / sizeof(*arglist))) < 0)
421			break;
422		if (c < com->c_minargs) {
423			printf("%s requires at least %d arg(s)\n",
424			    com->c_name, com->c_minargs);
425			break;
426		}
427		if (c > com->c_maxargs) {
428			printf("%s takes no more than %d arg(s)\n",
429			    com->c_name, com->c_maxargs);
430			break;
431		}
432		e = (*com->c_func)(arglist);
433		break;
434
435	case NOLIST:
436		/*
437		 * Just the constant zero, for exiting,
438		 * eg.
439		 */
440		e = (*com->c_func)(0);
441		break;
442
443	default:
444		errx(1, "Unknown argtype");
445	}
446
447out:
448	/*
449	 * Exit the current source file on
450	 * error.
451	 */
452	if (e) {
453		if (e < 0)
454			return (1);
455		if (loading)
456			return (1);
457		if (sourcing)
458			unstack();
459		return (0);
460	}
461	if (com == NULL)
462		return (0);
463	if (value("autoprint") != NULL && com->c_argtype & P)
464		if ((dot->m_flag & MDELETED) == 0) {
465			muvec[0] = dot - &message[0] + 1;
466			muvec[1] = 0;
467			type(muvec);
468		}
469	if (!sourcing && (com->c_argtype & T) == 0)
470		sawcom = 1;
471	return (0);
472}
473
474/*
475 * Set the size of the message vector used to construct argument
476 * lists to message list functions.
477 */
478void
479setmsize(sz)
480	int sz;
481{
482
483	if (msgvec != NULL)
484		(void)free(msgvec);
485	msgvec = calloc((unsigned)(sz + 1), sizeof(*msgvec));
486}
487
488/*
489 * Find the correct command in the command table corresponding
490 * to the passed command "word"
491 */
492
493__const struct cmd *
494lex(word)
495	char word[];
496{
497	const struct cmd *cp;
498
499	/*
500	 * ignore trailing chars after `#'
501	 *
502	 * lines with beginning `#' are comments
503	 * spaces before `#' are ignored in execute()
504	 */
505
506	if (*word == '#')
507	    *(word+1) = '\0';
508
509
510	for (cp = &cmdtab[0]; cp->c_name != NULL; cp++)
511		if (isprefix(word, cp->c_name))
512			return (cp);
513	return (NULL);
514}
515
516/*
517 * Determine if as1 is a valid prefix of as2.
518 * Return true if yep.
519 */
520int
521isprefix(as1, as2)
522	const char *as1, *as2;
523{
524	const char *s1, *s2;
525
526	s1 = as1;
527	s2 = as2;
528	while (*s1++ == *s2)
529		if (*s2++ == '\0')
530			return (1);
531	return (*--s1 == '\0');
532}
533
534/*
535 * The following gets called on receipt of an interrupt.  This is
536 * to abort printout of a command, mainly.
537 * Dispatching here when command() is inactive crashes rcv.
538 * Close all open files except 0, 1, 2, and the temporary.
539 * Also, unstack all source files.
540 */
541
542static int	inithdr;		/* am printing startup headers */
543
544/*ARGSUSED*/
545void
546intr(s)
547	int s;
548{
549
550	noreset = 0;
551	if (!inithdr)
552		sawcom++;
553	inithdr = 0;
554	while (sourcing)
555		unstack();
556
557	close_all_files();
558
559	if (image >= 0) {
560		(void)close(image);
561		image = -1;
562	}
563	fprintf(stderr, "Interrupt\n");
564	reset(0);
565}
566
567/*
568 * When we wake up after ^Z, reprint the prompt.
569 */
570void
571stop(s)
572	int s;
573{
574	sig_t old_action = signal(s, SIG_DFL);
575	sigset_t nset;
576
577	(void)sigemptyset(&nset);
578	(void)sigaddset(&nset, s);
579	(void)sigprocmask(SIG_UNBLOCK, &nset, NULL);
580	(void)kill(0, s);
581	(void)sigprocmask(SIG_BLOCK, &nset, NULL);
582	(void)signal(s, old_action);
583	if (reset_on_stop) {
584		reset_on_stop = 0;
585		reset(0);
586	}
587}
588
589/*
590 * Branch here on hangup signal and simulate "exit".
591 */
592/*ARGSUSED*/
593void
594hangup(s)
595	int s;
596{
597
598	/* nothing to do? */
599	exit(1);
600}
601
602/*
603 * Announce the presence of the current Mail version,
604 * give the message count, and print a header listing.
605 */
606void
607announce()
608{
609	int vec[2], mdot;
610
611	mdot = newfileinfo(0);
612	vec[0] = mdot;
613	vec[1] = 0;
614	dot = &message[mdot - 1];
615	if (msgCount > 0 && value("noheader") == NULL) {
616		inithdr++;
617		headers(vec);
618		inithdr = 0;
619	}
620}
621
622/*
623 * Announce information about the file we are editing.
624 * Return a likely place to set dot.
625 */
626int
627newfileinfo(omsgCount)
628	int omsgCount;
629{
630	struct message *mp;
631	int u, n, mdot, d, s;
632	char fname[PATHSIZE+1], zname[PATHSIZE+1], *ename;
633
634	for (mp = &message[omsgCount]; mp < &message[msgCount]; mp++)
635		if (mp->m_flag & MNEW)
636			break;
637	if (mp >= &message[msgCount])
638		for (mp = &message[omsgCount]; mp < &message[msgCount]; mp++)
639			if ((mp->m_flag & MREAD) == 0)
640				break;
641	if (mp < &message[msgCount])
642		mdot = mp - &message[0] + 1;
643	else
644		mdot = omsgCount + 1;
645	s = d = 0;
646	for (mp = &message[0], n = 0, u = 0; mp < &message[msgCount]; mp++) {
647		if (mp->m_flag & MNEW)
648			n++;
649		if ((mp->m_flag & MREAD) == 0)
650			u++;
651		if (mp->m_flag & MDELETED)
652			d++;
653		if (mp->m_flag & MSAVED)
654			s++;
655	}
656	ename = mailname;
657	if (getfold(fname, sizeof(fname) - 1) >= 0) {
658		strcat(fname, "/");
659		if (strncmp(fname, mailname, strlen(fname)) == 0) {
660			(void)snprintf(zname, sizeof(zname), "+%s",
661			    mailname + strlen(fname));
662			ename = zname;
663		}
664	}
665	printf("\"%s\": ", ename);
666	if (msgCount == 1)
667		printf("1 message");
668	else
669		printf("%d messages", msgCount);
670	if (n > 0)
671		printf(" %d new", n);
672	if (u-n > 0)
673		printf(" %d unread", u);
674	if (d > 0)
675		printf(" %d deleted", d);
676	if (s > 0)
677		printf(" %d saved", s);
678	if (readonly)
679		printf(" [Read only]");
680	printf("\n");
681	return (mdot);
682}
683
684/*
685 * Print the current version number.
686 */
687
688/*ARGSUSED*/
689int
690pversion(e)
691	int e;
692{
693
694	printf("Version %s\n", version);
695	return (0);
696}
697
698/*
699 * Load a file of user definitions.
700 */
701void
702load(name)
703	char *name;
704{
705	FILE *in, *oldin;
706
707	if ((in = Fopen(name, "r")) == NULL)
708		return;
709	oldin = input;
710	input = in;
711	loading = 1;
712	sourcing = 1;
713	commands();
714	loading = 0;
715	sourcing = 0;
716	input = oldin;
717	(void)Fclose(in);
718}
719