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