1/*	$OpenBSD: lex.c,v 1.43 2023/03/08 04:43:11 guenther Exp $	*/
2/*	$NetBSD: lex.c,v 1.10 1997/05/17 19:55:13 pk Exp $	*/
3
4/*
5 * Copyright (c) 1980, 1993
6 *	The Regents of the University of California.  All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 *    notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 *    notice, this list of conditions and the following disclaimer in the
15 *    documentation and/or other materials provided with the distribution.
16 * 3. Neither the name of the University nor the names of its contributors
17 *    may be used to endorse or promote products derived from this software
18 *    without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 * SUCH DAMAGE.
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
44char	*prompt = "& ";
45
46const struct cmd *com;	/* command we are running */
47
48/*
49 * Set up editing on the given file name.
50 * If the first character of name is %, we are considered to be
51 * editing the file, otherwise we are reading our mail which has
52 * signficance for mbox and so forth.
53 */
54int
55setfile(char *name)
56{
57	FILE *ibuf;
58	int i, fd;
59	struct stat stb;
60	char isedit = *name != '%';
61	const char *who = name[1] ? name + 1 : myname;
62	char tempname[PATHSIZE];
63	static int shudclob;
64
65	if ((name = expand(name)) == NULL)
66		return(-1);
67
68	if ((ibuf = Fopen(name, "r")) == NULL) {
69		if (!isedit && errno == ENOENT)
70			goto nomail;
71		warn("%s", name);
72		return(-1);
73	}
74
75	if (fstat(fileno(ibuf), &stb) == -1) {
76		warn("fstat");
77		(void)Fclose(ibuf);
78		return(-1);
79	}
80
81	switch (stb.st_mode & S_IFMT) {
82	case S_IFDIR:
83		(void)Fclose(ibuf);
84		warnc(EISDIR, "%s", name);
85		return(-1);
86
87	case S_IFREG:
88		break;
89
90	default:
91		(void)Fclose(ibuf);
92		warnc(EINVAL, "%s", name);
93		return(-1);
94	}
95
96	/*
97	 * Looks like all will be well.  We must now relinquish our
98	 * hold on the current set of stuff.  Must hold signals
99	 * while we are reading the new file, else we will ruin
100	 * the message[] data structure.
101	 */
102	holdsigs();
103	if (shudclob)
104		quit();
105
106	/*
107	 * Copy the messages into /tmp
108	 * and set pointers.
109	 */
110	readonly = 0;
111	if ((i = open(name, O_WRONLY)) == -1)
112		readonly++;
113	else
114		(void)close(i);
115	if (shudclob) {
116		(void)fclose(itf);
117		(void)fclose(otf);
118	}
119	shudclob = 1;
120	edit = isedit;
121	strlcpy(prevfile, mailname, PATHSIZE);
122	if (name != mailname)
123		strlcpy(mailname, name, sizeof(mailname));
124	mailsize = fsize(ibuf);
125	(void)snprintf(tempname, sizeof(tempname),
126	    "%s/mail.RxXXXXXXXXXX", tmpdir);
127	if ((fd = mkostemp(tempname, O_CLOEXEC)) == -1 ||
128	    (otf = fdopen(fd, "w")) == NULL)
129		err(1, "%s", tempname);
130	if ((itf = fopen(tempname, "re")) == NULL)
131		err(1, "%s", tempname);
132	(void)rm(tempname);
133	setptr(ibuf, (off_t)0);
134	setmsize(msgCount);
135	/*
136	 * New mail may have arrived while we were reading
137	 * the mail file, so reset mailsize to be where
138	 * we really are in the file...
139	 */
140	mailsize = ftell(ibuf);
141	(void)Fclose(ibuf);
142	relsesigs();
143	sawcom = 0;
144	if (!edit && msgCount == 0) {
145nomail:
146		fprintf(stderr, "No mail for %s\n", who);
147		return(-1);
148	}
149	return(0);
150}
151
152/*
153 * Incorporate any new mail that has arrived since we first
154 * started reading mail.
155 */
156int
157incfile(void)
158{
159	int newsize;
160	int omsgCount = msgCount;
161	FILE *ibuf;
162
163	ibuf = Fopen(mailname, "r");
164	if (ibuf == NULL)
165		return(-1);
166	holdsigs();
167	if (!spool_lock()) {
168		(void)Fclose(ibuf);
169		relsesigs();
170		return(-1);
171	}
172	newsize = fsize(ibuf);
173	/* make sure mail box has grown and is non-empty */
174	if (newsize == 0 || newsize <= mailsize) {
175		(void)Fclose(ibuf);
176		spool_unlock();
177		relsesigs();
178		return(newsize == mailsize ? 0 : -1);
179	}
180	setptr(ibuf, mailsize);
181	setmsize(msgCount);
182	mailsize = ftell(ibuf);
183	(void)Fclose(ibuf);
184	spool_unlock();
185	relsesigs();
186	return(msgCount - omsgCount);
187}
188
189
190int	*msgvec;
191int	reset_on_stop;			/* reset prompt if stopped */
192
193/*
194 * Interpret user commands one by one.  If standard input is not a tty,
195 * print no prompt.
196 */
197void
198commands(void)
199{
200	int n, sig, *sigp;
201	int eofloop = 0;
202	char linebuf[LINESIZE];
203
204	prompt:
205	for (;;) {
206		/*
207		 * Print the prompt, if needed.  Clear out
208		 * string space, and flush the output.
209		 */
210		if (!sourcing && value("interactive") != NULL) {
211			if ((value("autoinc") != NULL) && (incfile() > 0))
212				puts("New mail has arrived.");
213			reset_on_stop = 1;
214			printf("%s", prompt);
215		}
216		fflush(stdout);
217		sreset();
218		/*
219		 * Read a line of commands from the current input
220		 * and handle end of file specially.
221		 */
222		n = 0;
223		sig = 0;
224		sigp = sourcing ? NULL : &sig;
225		for (;;) {
226			if (readline(input, &linebuf[n], LINESIZE - n, sigp) < 0) {
227				if (sig) {
228					if (sig == SIGINT)
229						dointr();
230					else if (sig == SIGHUP)
231						/* nothing to do? */
232						exit(1);
233					else {
234						/* Stopped by job control */
235						(void)kill(0, sig);
236						if (reset_on_stop)
237							reset_on_stop = 0;
238					}
239					goto prompt;
240				}
241				if (n == 0)
242					n = -1;
243				break;
244			}
245			if ((n = strlen(linebuf)) == 0)
246				break;
247			n--;
248			if (linebuf[n] != '\\')
249				break;
250			linebuf[n++] = ' ';
251		}
252		reset_on_stop = 0;
253		if (n < 0) {
254				/* eof */
255			if (loading)
256				break;
257			if (sourcing) {
258				unstack();
259				continue;
260			}
261			if (value("interactive") != NULL &&
262			    value("ignoreeof") != NULL &&
263			    ++eofloop < 25) {
264				puts("Use \"quit\" to quit.");
265				continue;
266			}
267			break;
268		}
269		eofloop = 0;
270		if (execute(linebuf, 0))
271			break;
272	}
273}
274
275/*
276 * Execute a single command.
277 * Command functions return 0 for success, 1 for error, and -1
278 * for abort.  A 1 or -1 aborts a load or source.  A -1 aborts
279 * the interactive command loop.
280 * Contxt is non-zero if called while composing mail.
281 */
282int
283execute(char *linebuf, int contxt)
284{
285	char word[LINESIZE];
286	char *arglist[MAXARGC];
287	char *cp, *cp2;
288	int c, muvec[2];
289	int e = 1;
290
291	com = NULL;
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	for (cp = linebuf; isspace((unsigned char)*cp); cp++)
302		;
303	if (*cp == '!') {
304		if (sourcing) {
305			puts("Can't \"!\" while sourcing");
306			goto out;
307		}
308		shell(cp+1);
309		return(0);
310	}
311	cp2 = word;
312	while (*cp &&
313	        strchr(" \t0123456789$^.:/-+*'\"", (unsigned char)*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	if (sourcing && *word == '\0')
325		return(0);
326	com = lex(word);
327	if (com == NULL) {
328		printf("Unknown command: \"%s\"\n", word);
329		goto out;
330	}
331
332	/*
333	 * See if we should execute the command -- if a conditional
334	 * we always execute it, otherwise, check the state of cond.
335	 */
336	if ((com->c_argtype & F) == 0)
337		if ((cond == CRCV && !rcvmode) || (cond == CSEND && rcvmode))
338			return(0);
339
340	/*
341	 * Process the arguments to the command, depending
342	 * on the type he expects.  Default to an error.
343	 * If we are sourcing an interactive command, it's
344	 * an error.
345	 */
346	if (!rcvmode && (com->c_argtype & M) == 0) {
347		printf("May not execute \"%s\" while sending\n",
348		    com->c_name);
349		goto out;
350	}
351	if (sourcing && com->c_argtype & I) {
352		printf("May not execute \"%s\" while sourcing\n",
353		    com->c_name);
354		goto out;
355	}
356	if (readonly && com->c_argtype & W) {
357		printf("May not execute \"%s\" -- message file is read only\n",
358		   com->c_name);
359		goto out;
360	}
361	if (contxt && com->c_argtype & R) {
362		printf("Cannot recursively invoke \"%s\"\n", com->c_name);
363		goto out;
364	}
365	switch (com->c_argtype & ~(F|P|I|M|T|W|R)) {
366	case MSGLIST|STRLIST:
367		/*
368		 * A message list defaulting to nearest forward
369		 * legal message.
370		 */
371		if (msgvec == 0) {
372			puts("Illegal use of \"message list\"");
373			break;
374		}
375		/*
376		 * remove leading blanks.
377		 */
378		while (isspace((unsigned char)*cp))
379			cp++;
380
381		if (isdigit((unsigned char)*cp) || *cp == ':') {
382			if ((c = getmsglist(cp, msgvec, com->c_msgflag)) < 0)
383				break;
384			/* position to next space - past the message list */
385			while (!isspace((unsigned char)*cp))
386				cp++;
387			/* position to next non-space */
388			while (isspace((unsigned char)*cp))
389				cp++;
390		} else {
391			c = 0; /* no message list */
392		}
393
394		if (c  == 0) {
395			*msgvec = first(com->c_msgflag,
396				com->c_msgmask);
397			msgvec[1] = 0;
398		}
399		if (*msgvec == 0) {
400			puts("No applicable messages");
401			break;
402		}
403		/*
404		 * Just the straight string, with
405		 * leading blanks removed.
406		 */
407		while (isspace((unsigned char)*cp))
408			cp++;
409
410		e = (*com->c_func2)(msgvec, cp);
411		break;
412
413	case MSGLIST:
414		/*
415		 * A message list defaulting to nearest forward
416		 * legal message.
417		 */
418		if (msgvec == NULL) {
419			puts("Illegal use of \"message list\"");
420			break;
421		}
422		if ((c = getmsglist(cp, msgvec, com->c_msgflag)) < 0)
423			break;
424		if (c  == 0) {
425			*msgvec = first(com->c_msgflag,
426				com->c_msgmask);
427			msgvec[1] = 0;
428		}
429		if (*msgvec == 0) {
430			puts("No applicable messages");
431			break;
432		}
433		e = (*com->c_func)(msgvec);
434		break;
435
436	case NDMLIST:
437		/*
438		 * A message list with no defaults, but no error
439		 * if none exist.
440		 */
441		if (msgvec == 0) {
442			puts("Illegal use of \"message list\"");
443			break;
444		}
445		if (getmsglist(cp, msgvec, com->c_msgflag) < 0)
446			break;
447		e = (*com->c_func)(msgvec);
448		break;
449
450	case STRLIST:
451		/*
452		 * Just the straight string, with
453		 * leading blanks removed.
454		 */
455		while (isspace((unsigned char)*cp))
456			cp++;
457		e = (*com->c_func)(cp);
458		break;
459
460	case RAWLIST:
461		/*
462		 * A vector of strings, in shell style.
463		 */
464		if ((c = getrawlist(cp, arglist,
465				sizeof(arglist) / sizeof(*arglist))) < 0)
466			break;
467		if (c < com->c_minargs) {
468			printf("%s requires at least %d arg(s)\n",
469				com->c_name, com->c_minargs);
470			break;
471		}
472		if (c > com->c_maxargs) {
473			printf("%s takes no more than %d arg(s)\n",
474				com->c_name, com->c_maxargs);
475			break;
476		}
477		e = (*com->c_func)(arglist);
478		break;
479
480	case NOLIST:
481		/*
482		 * Just the constant zero, for exiting,
483		 * eg.
484		 */
485		e = (*com->c_func)(0);
486		break;
487
488	default:
489		errx(1, "Unknown argtype");
490	}
491
492out:
493	/*
494	 * Exit the current source file on
495	 * error.
496	 */
497	if (e) {
498		if (e < 0)
499			return(1);
500		if (loading)
501			return(1);
502		if (sourcing)
503			unstack();
504		return(0);
505	}
506	if (com == NULL)
507		return(0);
508	if (value("autoprint") != NULL && com->c_argtype & P)
509		if ((dot->m_flag & MDELETED) == 0) {
510			muvec[0] = dot - &message[0] + 1;
511			muvec[1] = 0;
512			type(muvec);
513		}
514	if (!sourcing && (com->c_argtype & T) == 0)
515		sawcom = 1;
516	return(0);
517}
518
519/*
520 * Set the size of the message vector used to construct argument
521 * lists to message list functions.
522 */
523void
524setmsize(int n)
525{
526	int *msgvec2;
527	size_t msize;
528
529	msize = (n + 1) * sizeof(*msgvec);
530	if ((msgvec2 = realloc(msgvec, msize)) == NULL)
531		err(1, "realloc");
532	msgvec = msgvec2;
533	memset(msgvec, 0, msize);
534}
535
536/*
537 * Find the correct command in the command table corresponding
538 * to the passed command "word"
539 */
540
541const struct cmd *
542lex(char *word)
543{
544	extern const struct cmd cmdtab[];
545	const struct cmd *cp;
546
547	if (word[0] == '#')
548		word = "#";
549	for (cp = &cmdtab[0]; cp->c_name != NULL; cp++)
550		if (isprefix(word, cp->c_name))
551			return(cp);
552	return(NULL);
553}
554
555/*
556 * Determine if as1 is a valid prefix of as2.
557 * Return true if yep.
558 */
559int
560isprefix(char *as1, char *as2)
561{
562	char *s1, *s2;
563
564	s1 = as1;
565	s2 = as2;
566	while (*s1++ == *s2)
567		if (*s2++ == '\0')
568			return(1);
569	return(*--s1 == '\0');
570}
571
572/*
573 * The following gets called on receipt of an interrupt.  This is
574 * to abort printout of a command, mainly.
575 * Dispatching here when command() is inactive crashes rcv.
576 * Close all open files except 0, 1, 2, and the temporary.
577 * Also, unstack all source files.
578 */
579int	inithdr;			/* am printing startup headers */
580
581void
582dointr(void)
583{
584
585	noreset = 0;
586	if (!inithdr)
587		sawcom++;
588	inithdr = 0;
589	while (sourcing)
590		unstack();
591
592	close_all_files();
593
594	if (image >= 0) {
595		(void)close(image);
596		image = -1;
597	}
598	fputs("Interrupt\n", stderr);
599}
600
601/*
602 * Announce the presence of the current Mail version,
603 * give the message count, and print a header listing.
604 */
605void
606announce(void)
607{
608	int vec[2], mdot;
609
610	mdot = newfileinfo(0);
611	vec[0] = mdot;
612	vec[1] = 0;
613	dot = &message[mdot - 1];
614	if (msgCount > 0 && value("noheader") == NULL) {
615		inithdr++;
616		headers(vec);
617		inithdr = 0;
618	}
619}
620
621/*
622 * Announce information about the file we are editing.
623 * Return a likely place to set dot.
624 */
625int
626newfileinfo(int omsgCount)
627{
628	struct message *mp;
629	int u, n, mdot, d, s;
630	char fname[PATHSIZE], zname[PATHSIZE], *ename;
631
632	for (mp = &message[omsgCount]; mp < &message[msgCount]; mp++)
633		if (mp->m_flag & MNEW)
634			break;
635	if (mp >= &message[msgCount])
636		for (mp = &message[omsgCount]; mp < &message[msgCount]; mp++)
637			if ((mp->m_flag & MREAD) == 0)
638				break;
639	if (mp < &message[msgCount])
640		mdot = mp - &message[0] + 1;
641	else
642		mdot = omsgCount + 1;
643	s = d = 0;
644	for (mp = &message[0], n = 0, u = 0; mp < &message[msgCount]; mp++) {
645		if (mp->m_flag & MNEW)
646			n++;
647		if ((mp->m_flag & MREAD) == 0)
648			u++;
649		if (mp->m_flag & MDELETED)
650			d++;
651		if (mp->m_flag & MSAVED)
652			s++;
653	}
654	ename = mailname;
655	if (getfold(fname, sizeof(fname)) >= 0) {
656		strlcat(fname, "/", sizeof(fname));
657		if (strncmp(fname, mailname, strlen(fname)) == 0) {
658			(void)snprintf(zname, sizeof(zname), "+%s",
659			    mailname + strlen(fname));
660			ename = zname;
661		}
662	}
663	printf("\"%s\": ", ename);
664	if (msgCount == 1)
665		fputs("1 message", stdout);
666	else
667		printf("%d messages", msgCount);
668	if (n > 0)
669		printf(" %d new", n);
670	if (u-n > 0)
671		printf(" %d unread", u);
672	if (d > 0)
673		printf(" %d deleted", d);
674	if (s > 0)
675		printf(" %d saved", s);
676	if (readonly)
677		fputs(" [Read only]", stdout);
678	putchar('\n');
679	return(mdot);
680}
681
682/*
683 * Print the current version number.
684 */
685int
686pversion(void *v)
687{
688	extern const char version[];
689
690	printf("Version %s\n", version);
691	return(0);
692}
693
694/*
695 * Load a file of user definitions.
696 */
697void
698load(char *name)
699{
700	FILE *in, *oldin;
701
702	if ((in = Fopen(name, "r")) == NULL)
703		return;
704	oldin = input;
705	input = in;
706	loading = 1;
707	sourcing = 1;
708	commands();
709	loading = 0;
710	sourcing = 0;
711	input = oldin;
712	(void)Fclose(in);
713}
714