xref: /freebsd/usr.bin/msgs/msgs.c (revision 2008043f386721d58158e37e0d7e50df8095942d)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1980, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 #ifndef lint
33 static const char copyright[] =
34 "@(#) Copyright (c) 1980, 1993\n\
35 	The Regents of the University of California.  All rights reserved.\n";
36 #endif /* not lint */
37 
38 #if 0
39 #ifndef lint
40 static char sccsid[] = "@(#)msgs.c	8.2 (Berkeley) 4/28/95";
41 #endif /* not lint */
42 #endif
43 
44 #include <sys/cdefs.h>
45 /*
46  * msgs - a user bulletin board program
47  *
48  * usage:
49  *	msgs [fhlopq] [[-]number]	to read messages
50  *	msgs -s				to place messages
51  *	msgs -c [-days]			to clean up the bulletin board
52  *
53  * prompt commands are:
54  *	y	print message
55  *	n	flush message, go to next message
56  *	q	flush message, quit
57  *	p	print message, turn on 'pipe thru more' mode
58  *	P	print message, turn off 'pipe thru more' mode
59  *	-	reprint last message
60  *	s[-][<num>] [<filename>]	save message
61  *	m[-][<num>]	mail with message in temp mbox
62  *	x	exit without flushing this message
63  *	<num>	print message number <num>
64  */
65 
66 #define V7		/* will look for TERM in the environment */
67 #define OBJECT		/* will object to messages without Subjects */
68 /* #define REJECT */	/* will reject messages without Subjects
69 			   (OBJECT must be defined also) */
70 /* #define UNBUFFERED *//* use unbuffered output */
71 
72 #include <sys/param.h>
73 #include <sys/stat.h>
74 #include <ctype.h>
75 #include <dirent.h>
76 #include <err.h>
77 #include <errno.h>
78 #include <fcntl.h>
79 #include <locale.h>
80 #include <pwd.h>
81 #include <setjmp.h>
82 #include <termcap.h>
83 #include <termios.h>
84 #include <signal.h>
85 #include <stdio.h>
86 #include <stdlib.h>
87 #include <string.h>
88 #include <time.h>
89 #include <unistd.h>
90 #include "pathnames.h"
91 
92 #define	CMODE	0644		/* bounds file creation	mode */
93 #define NO	0
94 #define YES	1
95 #define SUPERUSER	0	/* superuser uid */
96 #define DAEMON		1	/* daemon uid */
97 #define NLINES	24		/* default number of lines/crt screen */
98 #define NDAYS	21		/* default keep time for messages */
99 #define DAYS	*24*60*60	/* seconds/day */
100 #define MSGSRC	".msgsrc"	/* user's rc file */
101 #define BOUNDS	"bounds"	/* message bounds file */
102 #define NEXT	"Next message? [yq]"
103 #define MORE	"More? [ynq]"
104 #define NOMORE	"(No more) [q] ?"
105 
106 typedef	char	bool;
107 
108 static FILE	*msgsrc;
109 static FILE	*newmsg;
110 static const char *sep = "-";
111 static char	inbuf[BUFSIZ];
112 static char	fname[MAXPATHLEN];
113 static char	cmdbuf[MAXPATHLEN + MAXPATHLEN];
114 static char	subj[128];
115 static char	from[128];
116 static char	date[128];
117 static char	*ptr;
118 static char	*in;
119 static bool	local;
120 static bool	ruptible;
121 static bool	totty;
122 static bool	seenfrom;
123 static bool	seensubj;
124 static bool	blankline;
125 static bool	printing = NO;
126 static bool	mailing = NO;
127 static bool	quitit = NO;
128 static bool	sending = NO;
129 static bool	intrpflg = NO;
130 static uid_t	uid;
131 static int	msg;
132 static int	prevmsg;
133 static int	lct;
134 static int	nlines;
135 static int	Lpp = 0;
136 static time_t	t;
137 static time_t	keep;
138 
139 /* option initialization */
140 static bool	hdrs = NO;
141 static bool	qopt = NO;
142 static bool	hush = NO;
143 static bool	send_msg = NO;
144 static bool	locomode = NO;
145 static bool	use_pager = NO;
146 static bool	clean = NO;
147 static bool	lastcmd = NO;
148 static jmp_buf	tstpbuf;
149 
150 static void	ask(const char *);
151 static void	gfrsub(FILE *);
152 static int	linecnt(FILE *);
153 static int	next(char *);
154 static char	*nxtfld(char *);
155 static void	onsusp(int);
156 static void	onintr(int);
157 static void	prmesg(int);
158 static void	usage(void);
159 
160 int
161 main(int argc, char *argv[])
162 {
163 	bool newrc, already;
164 	int rcfirst = 0;		/* first message to print (from .rc) */
165 	int rcback = 0;			/* amount to back off of rcfirst */
166 	int firstmsg = 0, nextmsg = 0, lastmsg = 0;
167 	int blast = 0;
168 	struct stat buf;		/* stat to check access of bounds */
169 	FILE *bounds;
170 	char *cp;
171 
172 #ifdef UNBUFFERED
173 	setbuf(stdout, NULL);
174 #endif
175 	setlocale(LC_ALL, "");
176 
177 	time(&t);
178 	if (setuid(uid = getuid()) != 0)
179 		err(1, "setuid failed");
180 	ruptible = (signal(SIGINT, SIG_IGN) == SIG_DFL);
181 	if (ruptible)
182 		signal(SIGINT, SIG_DFL);
183 
184 	argc--, argv++;
185 	while (argc > 0) {
186 		if (isdigit(argv[0][0])) {	/* starting message # */
187 			rcfirst = atoi(argv[0]);
188 		}
189 		else if (isdigit(argv[0][1])) {	/* backward offset */
190 			rcback = atoi( &( argv[0][1] ) );
191 		}
192 		else {
193 			ptr = *argv;
194 			while (*ptr) switch (*ptr++) {
195 
196 			case '-':
197 				break;
198 
199 			case 'c':
200 				if (uid != SUPERUSER && uid != DAEMON)
201 					errx(1,
202 				"only the super-user can use the c flag");
203 				clean = YES;
204 				break;
205 
206 			case 'f':		/* silently */
207 				hush = YES;
208 				break;
209 
210 			case 'h':		/* headers only */
211 				hdrs = YES;
212 				break;
213 
214 			case 'l':		/* local msgs only */
215 				locomode = YES;
216 				break;
217 
218 			case 'o':		/* option to save last message */
219 				lastcmd = YES;
220 				break;
221 
222 			case 'p':		/* pipe thru 'more' during long msgs */
223 				use_pager = YES;
224 				break;
225 
226 			case 'q':		/* query only */
227 				qopt = YES;
228 				break;
229 
230 			case 's':		/* sending TO msgs */
231 				send_msg = YES;
232 				break;
233 
234 			default:
235 				usage();
236 			}
237 		}
238 		argc--, argv++;
239 	}
240 
241 	/*
242 	 * determine current message bounds
243 	 */
244 	snprintf(fname, sizeof(fname), "%s/%s", _PATH_MSGS, BOUNDS);
245 
246 	/*
247 	 * Test access rights to the bounds file
248 	 * This can be a little tricky.  if(send_msg), then
249 	 * we will create it.  We assume that if(send_msg),
250 	 * then you have write permission there.
251 	 * Else, it better be there, or we bail.
252 	 */
253 	if (send_msg != YES) {
254 		if (stat(fname, &buf) < 0) {
255 			if (hush != YES) {
256 				err(errno, "%s", fname);
257 			} else {
258 				exit(1);
259 			}
260 		}
261 	}
262 	bounds = fopen(fname, "r");
263 
264 	if (bounds != NULL) {
265 		fscanf(bounds, "%d %d\n", &firstmsg, &lastmsg);
266 		fclose(bounds);
267 		blast = lastmsg;	/* save upper bound */
268 	}
269 
270 	if (clean)
271 		keep = t - (rcback? rcback : NDAYS) DAYS;
272 
273 	if (clean || bounds == NULL) {	/* relocate message bounds */
274 		struct dirent *dp;
275 		struct stat stbuf;
276 		bool seenany = NO;
277 		DIR	*dirp;
278 
279 		dirp = opendir(_PATH_MSGS);
280 		if (dirp == NULL)
281 			err(errno, "%s", _PATH_MSGS);
282 
283 		firstmsg = 32767;
284 		lastmsg = 0;
285 
286 		for (dp = readdir(dirp); dp != NULL; dp = readdir(dirp)){
287 			cp = dp->d_name;
288 			int i = 0;
289 
290 			if (dp->d_ino == 0)
291 				continue;
292 			if (dp->d_namlen == 0)
293 				continue;
294 
295 			if (clean)
296 				snprintf(inbuf, sizeof(inbuf), "%s/%s", _PATH_MSGS, cp);
297 
298 			while (isdigit(*cp))
299 				i = i * 10 + *cp++ - '0';
300 			if (*cp)
301 				continue;	/* not a message! */
302 
303 			if (clean) {
304 				if (stat(inbuf, &stbuf) != 0)
305 					continue;
306 				if (stbuf.st_mtime < keep
307 				    && stbuf.st_mode&S_IWRITE) {
308 					unlink(inbuf);
309 					continue;
310 				}
311 			}
312 
313 			if (i > lastmsg)
314 				lastmsg = i;
315 			if (i < firstmsg)
316 				firstmsg = i;
317 			seenany = YES;
318 		}
319 		closedir(dirp);
320 
321 		if (!seenany) {
322 			if (blast != 0)	/* never lower the upper bound! */
323 				lastmsg = blast;
324 			firstmsg = lastmsg + 1;
325 		}
326 		else if (blast > lastmsg)
327 			lastmsg = blast;
328 
329 		if (!send_msg) {
330 			bounds = fopen(fname, "w");
331 			if (bounds == NULL)
332 				err(errno, "%s", fname);
333 			chmod(fname, CMODE);
334 			fprintf(bounds, "%d %d\n", firstmsg, lastmsg);
335 			fclose(bounds);
336 		}
337 	}
338 
339 	if (send_msg) {
340 		/*
341 		 * Send mode - place msgs in _PATH_MSGS
342 		 */
343 		bounds = fopen(fname, "w");
344 		if (bounds == NULL)
345 			err(errno, "%s", fname);
346 
347 		nextmsg = lastmsg + 1;
348 		snprintf(fname, sizeof(fname), "%s/%d", _PATH_MSGS, nextmsg);
349 		newmsg = fopen(fname, "w");
350 		if (newmsg == NULL)
351 			err(errno, "%s", fname);
352 		chmod(fname, CMODE);
353 
354 		fprintf(bounds, "%d %d\n", firstmsg, nextmsg);
355 		fclose(bounds);
356 
357 		sending = YES;
358 		if (ruptible)
359 			signal(SIGINT, onintr);
360 
361 		if (isatty(fileno(stdin))) {
362 			ptr = getpwuid(uid)->pw_name;
363 			printf("Message %d:\nFrom %s %sSubject: ",
364 				nextmsg, ptr, ctime(&t));
365 			fflush(stdout);
366 			fgets(inbuf, sizeof inbuf, stdin);
367 			putchar('\n');
368 			fflush(stdout);
369 			fprintf(newmsg, "From %s %sSubject: %s\n",
370 				ptr, ctime(&t), inbuf);
371 			blankline = seensubj = YES;
372 		}
373 		else
374 			blankline = seensubj = NO;
375 		for (;;) {
376 			fgets(inbuf, sizeof inbuf, stdin);
377 			if (feof(stdin) || ferror(stdin))
378 				break;
379 			blankline = (blankline || (inbuf[0] == '\n'));
380 			seensubj = (seensubj || (!blankline && (strncmp(inbuf, "Subj", 4) == 0)));
381 			fputs(inbuf, newmsg);
382 		}
383 #ifdef OBJECT
384 		if (!seensubj) {
385 			printf("NOTICE: Messages should have a Subject field!\n");
386 #ifdef REJECT
387 			unlink(fname);
388 #endif
389 			exit(1);
390 		}
391 #endif
392 		exit(ferror(stdin));
393 	}
394 	if (clean)
395 		exit(0);
396 
397 	/*
398 	 * prepare to display messages
399 	 */
400 	totty = (isatty(fileno(stdout)) != 0);
401 	use_pager = use_pager && totty;
402 
403 	if ((cp = getenv("HOME")) == NULL || *cp == '\0') {
404 		fprintf(stderr, "Error, no home directory!\n");
405 		exit(1);
406 	}
407 	snprintf(fname, sizeof(fname), "%s/%s", cp, MSGSRC);
408 	msgsrc = fopen(fname, "r");
409 	if (msgsrc) {
410 		newrc = NO;
411 		fscanf(msgsrc, "%d\n", &nextmsg);
412 		fclose(msgsrc);
413 		if (nextmsg > lastmsg+1) {
414 			printf("Warning: bounds have been reset (%d, %d)\n",
415 				firstmsg, lastmsg);
416 			truncate(fname, (off_t)0);
417 			newrc = YES;
418 		}
419 		else if (!rcfirst)
420 			rcfirst = nextmsg - rcback;
421 	}
422 	else
423 		newrc = YES;
424 	msgsrc = fopen(fname, "r+");
425 	if (msgsrc == NULL)
426 		msgsrc = fopen(fname, "w");
427 	if (msgsrc == NULL)
428 		err(errno, "%s", fname);
429 	if (rcfirst) {
430 		if (rcfirst > lastmsg+1) {
431 			printf("Warning: the last message is number %d.\n",
432 				lastmsg);
433 			rcfirst = nextmsg;
434 		}
435 		if (rcfirst > firstmsg)
436 			firstmsg = rcfirst;	/* don't set below first msg */
437 	}
438 	if (newrc) {
439 		nextmsg = firstmsg;
440 		rewind(msgsrc);
441 		fprintf(msgsrc, "%d\n", nextmsg);
442 		fflush(msgsrc);
443 	}
444 
445 #ifdef V7
446 	if (totty) {
447 		struct winsize win;
448 		if (ioctl(fileno(stdout), TIOCGWINSZ, &win) != -1)
449 			Lpp = win.ws_row;
450 		if (Lpp <= 0) {
451 			if (tgetent(inbuf, getenv("TERM")) <= 0
452 			    || (Lpp = tgetnum("li")) <= 0) {
453 				Lpp = NLINES;
454 			}
455 		}
456 	}
457 #endif
458 	Lpp -= 6;	/* for headers, etc. */
459 
460 	already = NO;
461 	prevmsg = firstmsg;
462 	printing = YES;
463 	if (ruptible)
464 		signal(SIGINT, onintr);
465 
466 	/*
467 	 * Main program loop
468 	 */
469 	for (msg = firstmsg; msg <= lastmsg; msg++) {
470 
471 		snprintf(fname, sizeof(fname), "%s/%d", _PATH_MSGS, msg);
472 		newmsg = fopen(fname, "r");
473 		if (newmsg == NULL)
474 			continue;
475 
476 		gfrsub(newmsg);		/* get From and Subject fields */
477 		if (locomode && !local) {
478 			fclose(newmsg);
479 			continue;
480 		}
481 
482 		if (qopt) {	/* This has to be located here */
483 			printf("There are new messages.\n");
484 			exit(0);
485 		}
486 
487 		if (already && !hdrs)
488 			putchar('\n');
489 
490 		/*
491 		 * Print header
492 		 */
493 		if (totty)
494 			signal(SIGTSTP, onsusp);
495 		(void) setjmp(tstpbuf);
496 		already = YES;
497 		nlines = 2;
498 		if (seenfrom) {
499 			printf("Message %d:\nFrom %s %s", msg, from, date);
500 			nlines++;
501 		}
502 		if (seensubj) {
503 			printf("Subject: %s", subj);
504 			nlines++;
505 		}
506 		else {
507 			if (seenfrom) {
508 				putchar('\n');
509 				nlines++;
510 			}
511 			while (nlines < 6
512 			    && fgets(inbuf, sizeof inbuf, newmsg)
513 			    && inbuf[0] != '\n') {
514 				fputs(inbuf, stdout);
515 				nlines++;
516 			}
517 		}
518 
519 		lct = linecnt(newmsg);
520 		if (lct)
521 			printf("(%d%sline%s) ", lct, seensubj? " " : " more ",
522 			    (lct == 1) ? "" : "s");
523 
524 		if (hdrs) {
525 			printf("\n-----\n");
526 			fclose(newmsg);
527 			continue;
528 		}
529 
530 		/*
531 		 * Ask user for command
532 		 */
533 		if (totty)
534 			ask(lct? MORE : (msg==lastmsg? NOMORE : NEXT));
535 		else
536 			inbuf[0] = 'y';
537 		if (totty)
538 			signal(SIGTSTP, SIG_DFL);
539 cmnd:
540 		in = inbuf;
541 		switch (*in) {
542 			case 'x':
543 				/* FALLTHROUGH */
544 			case 'X':
545 				exit(0);
546 				/* NOTREACHED */
547 
548 			case 'q':
549 				/* FALLTHROUGH */
550 			case 'Q':
551 				quitit = YES;
552 				printf("--Postponed--\n");
553 				exit(0);
554 				/* NOTREACHED */
555 
556 			case 'n':
557 				/* FALLTHROUGH */
558 			case 'N':
559 				if (msg >= nextmsg) sep = "Flushed";
560 				prevmsg = msg;
561 				break;
562 
563 			case 'p':
564 				/* FALLTHROUGH */
565 			case 'P':
566 				use_pager = (*in++ == 'p');
567 				/* FALLTHROUGH */
568 			case '\n':
569 				/* FALLTHROUGH */
570 			case 'y':
571 			default:
572 				if (*in == '-') {
573 					msg = prevmsg-1;
574 					sep = "replay";
575 					break;
576 				}
577 				if (isdigit(*in)) {
578 					msg = next(in);
579 					sep = in;
580 					break;
581 				}
582 
583 				prmesg(nlines + lct + (seensubj? 1 : 0));
584 				prevmsg = msg;
585 
586 		}
587 
588 		printf("--%s--\n", sep);
589 		sep = "-";
590 		if (msg >= nextmsg) {
591 			nextmsg = msg + 1;
592 			rewind(msgsrc);
593 			fprintf(msgsrc, "%d\n", nextmsg);
594 			fflush(msgsrc);
595 		}
596 		if (newmsg)
597 			fclose(newmsg);
598 		if (quitit)
599 			break;
600 	}
601 
602 	/*
603 	 * Make sure .rc file gets updated
604 	 */
605 	if (--msg >= nextmsg) {
606 		nextmsg = msg + 1;
607 		rewind(msgsrc);
608 		fprintf(msgsrc, "%d\n", nextmsg);
609 		fflush(msgsrc);
610 	}
611 	if (already && !quitit && lastcmd && totty) {
612 		/*
613 		 * save or reply to last message?
614 		 */
615 		msg = prevmsg;
616 		ask(NOMORE);
617 		if (inbuf[0] == '-' || isdigit(inbuf[0]))
618 			goto cmnd;
619 	}
620 	if (!(already || hush || qopt))
621 		printf("No new messages.\n");
622 	exit(0);
623 	/* NOTREACHED */
624 }
625 
626 static void
627 usage(void)
628 {
629 	fprintf(stderr, "usage: msgs [fhlopq] [[-]number]\n");
630 	exit(1);
631 }
632 
633 static void
634 prmesg(int length)
635 {
636 	FILE *outf;
637 	char *env_pager;
638 
639 	if (use_pager && length > Lpp) {
640 		signal(SIGPIPE, SIG_IGN);
641 		signal(SIGQUIT, SIG_IGN);
642 		if ((env_pager = getenv("PAGER")) == NULL) {
643 			snprintf(cmdbuf, sizeof(cmdbuf), _PATH_PAGER, Lpp);
644 		} else {
645 			snprintf(cmdbuf, sizeof(cmdbuf), "%s", env_pager);
646 		}
647 		outf = popen(cmdbuf, "w");
648 		if (!outf)
649 			outf = stdout;
650 		else
651 			setbuf(outf, (char *)NULL);
652 	}
653 	else
654 		outf = stdout;
655 
656 	if (seensubj)
657 		putc('\n', outf);
658 
659 	while (fgets(inbuf, sizeof inbuf, newmsg)) {
660 		fputs(inbuf, outf);
661 		if (ferror(outf)) {
662 			clearerr(outf);
663 			break;
664 		}
665 	}
666 
667 	if (outf != stdout) {
668 		pclose(outf);
669 		signal(SIGPIPE, SIG_DFL);
670 		signal(SIGQUIT, SIG_DFL);
671 	}
672 	else {
673 		fflush(stdout);
674 	}
675 
676 	/* force wait on output */
677 	tcdrain(fileno(stdout));
678 }
679 
680 static void
681 onintr(int unused __unused)
682 {
683 	signal(SIGINT, onintr);
684 	if (mailing)
685 		unlink(fname);
686 	if (sending) {
687 		unlink(fname);
688 		puts("--Killed--");
689 		exit(1);
690 	}
691 	if (printing) {
692 		putchar('\n');
693 		if (hdrs)
694 			exit(0);
695 		sep = "Interrupt";
696 		if (newmsg)
697 			fseeko(newmsg, (off_t)0, SEEK_END);
698 		intrpflg = YES;
699 	}
700 }
701 
702 /*
703  * We have just gotten a susp.  Suspend and prepare to resume.
704  */
705 static void
706 onsusp(int unused __unused)
707 {
708 	signal(SIGTSTP, SIG_DFL);
709 	sigsetmask(0);
710 	kill(0, SIGTSTP);
711 	signal(SIGTSTP, onsusp);
712 	if (!mailing)
713 		longjmp(tstpbuf, 0);
714 }
715 
716 static int
717 linecnt(FILE *f)
718 {
719 	off_t oldpos = ftello(f);
720 	int l = 0;
721 	char lbuf[BUFSIZ];
722 
723 	while (fgets(lbuf, sizeof lbuf, f))
724 		l++;
725 	clearerr(f);
726 	fseeko(f, oldpos, SEEK_SET);
727 	return (l);
728 }
729 
730 static int
731 next(char *buf)
732 {
733 	int i;
734 	sscanf(buf, "%d", &i);
735 	sprintf(buf, "Goto %d", i);
736 	return(--i);
737 }
738 
739 static void
740 ask(const char *prompt)
741 {
742 	char	inch;
743 	int	n, cmsg, fd;
744 	off_t	oldpos;
745 	FILE	*cpfrom, *cpto;
746 
747 	printf("%s ", prompt);
748 	fflush(stdout);
749 	intrpflg = NO;
750 	(void) fgets(inbuf, sizeof inbuf, stdin);
751 	if ((n = strlen(inbuf)) > 0 && inbuf[n - 1] == '\n')
752 		inbuf[n - 1] = '\0';
753 	if (intrpflg)
754 		inbuf[0] = 'x';
755 
756 	/*
757 	 * Handle 'mail' and 'save' here.
758 	 */
759 	if ((inch = inbuf[0]) == 's' || inch == 'm') {
760 		if (inbuf[1] == '-')
761 			cmsg = prevmsg;
762 		else if (isdigit(inbuf[1]))
763 			cmsg = atoi(&inbuf[1]);
764 		else
765 			cmsg = msg;
766 		snprintf(fname, sizeof(fname), "%s/%d", _PATH_MSGS, cmsg);
767 
768 		oldpos = ftello(newmsg);
769 
770 		cpfrom = fopen(fname, "r");
771 		if (!cpfrom) {
772 			printf("Message %d not found\n", cmsg);
773 			ask (prompt);
774 			return;
775 		}
776 
777 		if (inch == 's') {
778 			in = nxtfld(inbuf);
779 			if (*in) {
780 				for (n=0; in[n] > ' '; n++) { /* sizeof fname? */
781 					fname[n] = in[n];
782 				}
783 				fname[n] = '\0';
784 			}
785 			else
786 				strcpy(fname, "Messages");
787 			fd = open(fname, O_RDWR|O_EXCL|O_CREAT|O_APPEND);
788 		}
789 		else {
790 			strcpy(fname, _PATH_TMP);
791 			fd = mkstemp(fname);
792 			if (fd != -1) {
793 				snprintf(cmdbuf, sizeof(cmdbuf), _PATH_MAIL,
794 				    fname);
795 				mailing = YES;
796 			}
797 		}
798 		if (fd == -1 || (cpto = fdopen(fd, "a")) == NULL) {
799 			if (fd != -1)
800 				close(fd);
801 			warn("%s", fname);
802 			mailing = NO;
803 			fseeko(newmsg, oldpos, SEEK_SET);
804 			ask(prompt);
805 			fclose(cpfrom);
806 			return;
807 		}
808 
809 		while ((n = fread(inbuf, 1, sizeof inbuf, cpfrom)))
810 			fwrite(inbuf, 1, n, cpto);
811 
812 		fclose(cpfrom);
813 		fclose(cpto);
814 		fseeko(newmsg, oldpos, SEEK_SET);/* reposition current message */
815 		if (inch == 's')
816 			printf("Message %d saved in \"%s\"\n", cmsg, fname);
817 		else {
818 			system(cmdbuf);
819 			unlink(fname);
820 			mailing = NO;
821 		}
822 		ask(prompt);
823 	}
824 }
825 
826 static void
827 gfrsub(FILE *infile)
828 {
829 	off_t frompos;
830 	int count;
831 
832 	seensubj = seenfrom = NO;
833 	local = YES;
834 	subj[0] = from[0] = date[0] = '\0';
835 
836 	/*
837 	 * Is this a normal message?
838 	 */
839 	if (fgets(inbuf, sizeof inbuf, infile)) {
840 		if (strncmp(inbuf, "From", 4)==0) {
841 			/*
842 			 * expected form starts with From
843 			 */
844 			seenfrom = YES;
845 			frompos = ftello(infile);
846 			ptr = from;
847 			in = nxtfld(inbuf);
848 			if (*in) {
849 				count = sizeof(from) - 1;
850 				while (*in && *in > ' ' && count-- > 0) {
851 					if (*in == ':' || *in == '@' ||
852 					    *in == '!')
853 						local = NO;
854 					*ptr++ = *in++;
855 				}
856 			}
857 			*ptr = '\0';
858 			if (*(in = nxtfld(in)))
859 				strlcpy(date, in, sizeof date);
860 			else {
861 				date[0] = '\n';
862 				date[1] = '\0';
863 			}
864 		}
865 		else {
866 			/*
867 			 * not the expected form
868 			 */
869 			rewind(infile);
870 			return;
871 		}
872 	}
873 	else
874 		/*
875 		 * empty file ?
876 		 */
877 		return;
878 
879 	/*
880 	 * look for Subject line until EOF or a blank line
881 	 */
882 	while (fgets(inbuf, sizeof inbuf, infile)
883 	    && !(blankline = (inbuf[0] == '\n'))) {
884 		/*
885 		 * extract Subject line
886 		 */
887 		if (!seensubj && strncmp(inbuf, "Subj", 4)==0) {
888 			seensubj = YES;
889 			frompos = ftello(infile);
890 			strlcpy(subj, nxtfld(inbuf), sizeof subj);
891 		}
892 	}
893 	if (!blankline)
894 		/*
895 		 * ran into EOF
896 		 */
897 		fseeko(infile, frompos, SEEK_SET);
898 
899 	if (!seensubj)
900 		/*
901 		 * for possible use with Mail
902 		 */
903 		strlcpy(subj, "(No Subject)\n", sizeof subj);
904 }
905 
906 static char *
907 nxtfld(char *s)
908 {
909 	if (*s) while (*s && !isspace(*s)) s++;     /* skip over this field */
910 	if (*s) while (*s && isspace(*s)) s++;    /* find start of next field */
911 	return (s);
912 }
913