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msgs.c revision 1.17
      1 /*	$NetBSD: msgs.c,v 1.17 2001/07/01 00:20:47 mjl Exp $	*/
      2 
      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. All advertising materials mentioning features or use of this software
     16  *    must display the following acknowledgement:
     17  *	This product includes software developed by the University of
     18  *	California, Berkeley and its contributors.
     19  * 4. Neither the name of the University nor the names of its contributors
     20  *    may be used to endorse or promote products derived from this software
     21  *    without specific prior written permission.
     22  *
     23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     33  * SUCH DAMAGE.
     34  */
     35 
     36 #include <sys/cdefs.h>
     37 #ifndef lint
     38 __COPYRIGHT("@(#) Copyright (c) 1980, 1993\n\
     39 	The Regents of the University of California.  All rights reserved.\n");
     40 #endif /* not lint */
     41 
     42 #ifndef lint
     43 #if 0
     44 static char sccsid[] = "@(#)msgs.c	8.2 (Berkeley) 4/28/95";
     45 #else
     46 __RCSID("$NetBSD: msgs.c,v 1.17 2001/07/01 00:20:47 mjl Exp $");
     47 #endif
     48 #endif /* not lint */
     49 
     50 /*
     51  * msgs - a user bulletin board program
     52  *
     53  * usage:
     54  *	msgs [fhlopqr] [[-]number]	to read messages
     55  *	msgs -s				to place messages
     56  *	msgs -c [-days]			to clean up the bulletin board
     57  *
     58  * prompt commands are:
     59  *	y	print message
     60  *	n	flush message, go to next message
     61  *	q	flush message, quit
     62  *	p	print message, turn on 'pipe thru more' mode
     63  *	P	print message, turn off 'pipe thru more' mode
     64  *	-	reprint last message
     65  *	s[-][<num>] [<filename>]	save message
     66  *	m[-][<num>]	mail with message in temp mbox
     67  *	x	exit without flushing this message
     68  *	<num>	print message number <num>
     69  */
     70 
     71 #define V7		/* will look for TERM in the environment */
     72 #define OBJECT		/* will object to messages without Subjects */
     73 #define REJECT		/* will reject messages without Subjects
     74 			   (OBJECT must be defined also) */
     75 /*#define UNBUFFERED */	/* use unbuffered output */
     76 
     77 #include <sys/param.h>
     78 #include <sys/ioctl.h>
     79 #include <sys/stat.h>
     80 
     81 #include <ctype.h>
     82 #include <dirent.h>
     83 #include <err.h>
     84 #include <errno.h>
     85 #include <pwd.h>
     86 #include <setjmp.h>
     87 #include <signal.h>
     88 #include <stdio.h>
     89 #include <stdlib.h>
     90 #include <string.h>
     91 #include <termcap.h>
     92 #include <termios.h>
     93 #include <time.h>
     94 #include <unistd.h>
     95 
     96 #include "pathnames.h"
     97 
     98 #define CMODE	0664		/* bounds file creation mode */
     99 #define NO	0
    100 #define YES	1
    101 #define SUPERUSER	0	/* superuser uid */
    102 #define DAEMON		1	/* daemon uid */
    103 #define NLINES	24		/* default number of lines/crt screen */
    104 #define NDAYS	21		/* default keep time for messages */
    105 #define DAYS	*24*60*60	/* seconds/day */
    106 #define MSGSRC	".msgsrc"	/* user's rc file */
    107 #define BOUNDS	"bounds"	/* message bounds file */
    108 #define NEXT	"Next message? [yq]"
    109 #define MORE	"More? [ynq]"
    110 #define NOMORE	"(No more) [q] ?"
    111 
    112 typedef	char	bool;
    113 
    114 FILE	*msgsrc;
    115 FILE	*newmsg;
    116 char	*sep = "-";
    117 char	inbuf[BUFSIZ];
    118 char	fname[MAXPATHLEN];
    119 char	cmdbuf[MAXPATHLEN + 16];
    120 char	subj[128];
    121 char	from[128];
    122 char	date[128];
    123 char	*ptr;
    124 char	*in;
    125 bool	local;
    126 bool	ruptible;
    127 bool	totty;
    128 bool	seenfrom;
    129 bool	seensubj;
    130 bool	blankline;
    131 bool	printing = NO;
    132 bool	mailing = NO;
    133 bool	quitit = NO;
    134 bool	sending = NO;
    135 bool	intrpflg = NO;
    136 bool	restricted = NO;
    137 int	uid;
    138 int	msg;
    139 int	prevmsg;
    140 int	lct;
    141 int	nlines;
    142 int	Lpp = 0;
    143 time_t	t;
    144 time_t	keep;
    145 
    146 void	ask __P((char *));
    147 void	gfrsub __P((FILE *));
    148 int	linecnt __P((FILE *));
    149 int	main __P((int, char *[]));
    150 int	next __P((char *));
    151 char	*nxtfld __P((char *));
    152 void	onintr __P((int));
    153 void	onsusp __P((int));
    154 void	prmesg __P((int));
    155 
    156 /* option initialization */
    157 bool	hdrs = NO;
    158 bool	qopt = NO;
    159 bool	hush = NO;
    160 bool	send_msg = NO;
    161 bool	locomode = NO;
    162 bool	use_pager = NO;
    163 bool	clean = NO;
    164 bool	lastcmd = NO;
    165 jmp_buf	tstpbuf;
    166 
    167 int
    168 main(argc, argv)
    169 	int argc; char *argv[];
    170 {
    171 	bool newrc, already;
    172 	int rcfirst = 0;		/* first message to print (from .rc) */
    173 	int rcback = 0;			/* amount to back off of rcfirst */
    174 	int firstmsg, nextmsg, lastmsg = 0;
    175 	int blast = 0;
    176 	FILE *bounds;
    177 	struct passwd *pw;
    178 
    179 #ifdef UNBUFFERED
    180 	setbuf(stdout, NULL);
    181 #endif
    182 
    183 	time(&t);
    184 	setuid(uid = getuid());
    185 	ruptible = (signal(SIGINT, SIG_IGN) == SIG_DFL);
    186 	if (ruptible)
    187 		signal(SIGINT, SIG_DFL);
    188 
    189 	argc--, argv++;
    190 	while (argc > 0) {
    191 		if (isdigit((unsigned char)argv[0][0])) {/* starting message # */
    192 			rcfirst = atoi(argv[0]);
    193 		}
    194 		else if (isdigit((unsigned char)argv[0][1])) {/* backward offset */
    195 			rcback = atoi( &( argv[0][1] ) );
    196 		}
    197 		else {
    198 			ptr = *argv;
    199 			while (*ptr) switch (*ptr++) {
    200 
    201 			case '-':
    202 				break;
    203 
    204 			case 'c':
    205 				if (uid != SUPERUSER && uid != DAEMON) {
    206 					fprintf(stderr, "Sorry\n");
    207 					exit(1);
    208 				}
    209 				clean = YES;
    210 				break;
    211 
    212 			case 'f':		/* silently */
    213 				hush = YES;
    214 				break;
    215 
    216 			case 'h':		/* headers only */
    217 				hdrs = YES;
    218 				break;
    219 
    220 			case 'l':		/* local msgs only */
    221 				locomode = YES;
    222 				break;
    223 
    224 			case 'o':		/* option to save last message */
    225 				lastcmd = YES;
    226 				break;
    227 
    228 			case 'p':		/* pipe thru 'more' during long msgs */
    229 				use_pager = YES;
    230 				break;
    231 
    232 			case 'q':		/* query only */
    233 				qopt = YES;
    234 				break;
    235 
    236                         case 'r':               /* restricted */
    237                                 restricted = YES;
    238                                 break;
    239 
    240 
    241 			case 's':		/* sending TO msgs */
    242 				send_msg = YES;
    243 				break;
    244 
    245 			default:
    246 				fprintf(stderr,
    247 					"usage: msgs [cfhlopqrs] [[-]number]\n");
    248 				exit(1);
    249 			}
    250 		}
    251 		argc--, argv++;
    252 	}
    253 
    254 	/*
    255 	 * determine current message bounds
    256 	 */
    257 	snprintf(fname, sizeof (fname), "%s/%s", _PATH_MSGS, BOUNDS);
    258 	bounds = fopen(fname, "r");
    259 
    260 	if (bounds != NULL) {
    261 		if (fscanf(bounds, "%d %d\n", &firstmsg, &lastmsg) < 2)
    262 			firstmsg = lastmsg = 0;
    263 		fclose(bounds);
    264 		blast = lastmsg;	/* save upper bound */
    265 	}
    266 
    267 	if (clean)
    268 		keep = t - (rcback? rcback : NDAYS) DAYS;
    269 
    270 	if (clean || bounds == NULL) {	/* relocate message bounds */
    271 		struct dirent *dp;
    272 		struct stat stbuf;
    273 		bool seenany = NO;
    274 		DIR	*dirp;
    275 
    276 		dirp = opendir(_PATH_MSGS);
    277 		if (dirp == NULL) {
    278 			perror(_PATH_MSGS);
    279 			exit(errno);
    280 		}
    281 		chmod(fname, CMODE);
    282 
    283 		firstmsg = 32767;
    284 		lastmsg = 0;
    285 
    286 		for (dp = readdir(dirp); dp != NULL; dp = readdir(dirp)){
    287 			char *cp = dp->d_name;
    288 			int i = 0;
    289 
    290 			if (dp->d_ino == 0)
    291 				continue;
    292 #ifndef __SVR4
    293 			if (dp->d_namlen == 0)
    294 				continue;
    295 #endif
    296 
    297 			if (clean)
    298 				snprintf(inbuf, sizeof (inbuf), "%s/%s",
    299 				    _PATH_MSGS, cp);
    300 
    301 			while (isdigit((unsigned char)*cp))
    302 				i = i * 10 + *cp++ - '0';
    303 			if (*cp)
    304 				continue;	/* not a message! */
    305 
    306 			if (clean) {
    307 				if (stat(inbuf, &stbuf) != 0)
    308 					continue;
    309 				if (stbuf.st_mtime < keep
    310 				    && stbuf.st_mode&S_IWRITE) {
    311 					unlink(inbuf);
    312 					continue;
    313 				}
    314 			}
    315 
    316 			if (i > lastmsg)
    317 				lastmsg = i;
    318 			if (i < firstmsg)
    319 				firstmsg = i;
    320 			seenany = YES;
    321 		}
    322 		closedir(dirp);
    323 
    324 		if (!seenany) {
    325 			if (blast != 0)	/* never lower the upper bound! */
    326 				lastmsg = blast;
    327 			firstmsg = lastmsg + 1;
    328 		}
    329 		else if (blast > lastmsg)
    330 			lastmsg = blast;
    331 
    332 		if (!send_msg) {
    333 			bounds = fopen(fname, "w");
    334 			if (bounds == NULL) {
    335 				perror(fname);
    336 				exit(errno);
    337 			}
    338 			chmod(fname, CMODE);
    339 			fprintf(bounds, "%d %d\n", firstmsg, lastmsg);
    340 			fclose(bounds);
    341 		}
    342 	}
    343 
    344 	if (send_msg) {
    345 		/*
    346 		 * Send mode - place msgs in _PATH_MSGS
    347 		 */
    348 		bounds = fopen(fname, "w");
    349 		if (bounds == NULL) {
    350 			perror(fname);
    351 			exit(errno);
    352 		}
    353 
    354 		nextmsg = lastmsg + 1;
    355 		snprintf(fname, sizeof (fname), "%s/%d", _PATH_MSGS, nextmsg);
    356 		newmsg = fopen(fname, "w");
    357 		if (newmsg == NULL) {
    358 			perror(fname);
    359 			exit(errno);
    360 		}
    361 		chmod(fname, 0644);
    362 
    363 		fprintf(bounds, "%d %d\n", firstmsg, nextmsg);
    364 		fclose(bounds);
    365 
    366 		sending = YES;
    367 		if (ruptible)
    368 			signal(SIGINT, onintr);
    369 
    370 		if (isatty(fileno(stdin))) {
    371 			pw = getpwuid(uid);
    372 			if (!pw) {
    373 				fprintf(stderr, "Who are you?\n");
    374 				exit(1);
    375 			}
    376 			printf("Message %d:\nFrom %s %sSubject: ",
    377 				nextmsg, pw->pw_name, ctime(&t));
    378 			fflush(stdout);
    379 			fgets(inbuf, sizeof inbuf, stdin);
    380 			putchar('\n');
    381 			fflush(stdout);
    382 			fprintf(newmsg, "From %s %sSubject: %s\n",
    383 				ptr, ctime(&t), inbuf);
    384 			blankline = seensubj = YES;
    385 		}
    386 		else
    387 			blankline = seensubj = NO;
    388 		for (;;) {
    389 			fgets(inbuf, sizeof inbuf, stdin);
    390 			if (feof(stdin) || ferror(stdin))
    391 				break;
    392 			blankline = (blankline || (inbuf[0] == '\n'));
    393 			seensubj = (seensubj || (!blankline && (strncmp(inbuf, "Subj", 4) == 0)));
    394 			fputs(inbuf, newmsg);
    395 		}
    396 #ifdef OBJECT
    397 		if (!seensubj) {
    398 			printf("NOTICE: Messages should have a Subject field!\n");
    399 #ifdef REJECT
    400 			unlink(fname);
    401 #endif
    402 			exit(1);
    403 		}
    404 #endif
    405 		exit(ferror(stdin));
    406 	}
    407 	if (clean)
    408 		exit(0);
    409 
    410 	/*
    411 	 * prepare to display messages
    412 	 */
    413 	totty = (isatty(fileno(stdout)) != 0);
    414 	use_pager = use_pager && totty;
    415 
    416 	{
    417 	    char *home = getenv("HOME");
    418 	    if(home == NULL || *home == '\0')
    419 		errx(1, "$HOME not set");
    420 	    snprintf(fname, sizeof (fname), "%s/%s", home, MSGSRC);
    421 	}
    422 	msgsrc = fopen(fname, "r");
    423 	if (msgsrc) {
    424 		newrc = NO;
    425                 fscanf(msgsrc, "%d\n", &nextmsg);
    426                 fclose(msgsrc);
    427                 if (nextmsg > lastmsg+1) {
    428 			printf("Warning: bounds have been reset (%d, %d)\n",
    429 				firstmsg, lastmsg);
    430 			truncate(fname, (off_t)0);
    431 			newrc = YES;
    432 		}
    433 		else if (!rcfirst)
    434 			rcfirst = nextmsg - rcback;
    435 	}
    436         else
    437         	newrc = YES;
    438         msgsrc = fopen(fname, "r+");
    439         if (msgsrc == NULL)
    440                msgsrc = fopen(fname, "w");
    441 	if (msgsrc == NULL) {
    442 		perror(fname);
    443 		exit(errno);
    444 	}
    445 	if (rcfirst) {
    446 		if (rcfirst > lastmsg+1) {
    447 			printf("Warning: the last message is number %d.\n",
    448 				lastmsg);
    449 			rcfirst = nextmsg;
    450 		}
    451 		if (rcfirst > firstmsg)
    452 			firstmsg = rcfirst;	/* don't set below first msg */
    453 	}
    454 	if (newrc) {
    455 		nextmsg = firstmsg;
    456 		fseek(msgsrc, 0L, 0);
    457 		fprintf(msgsrc, "%d\n", nextmsg);
    458 		fflush(msgsrc);
    459 	}
    460 
    461 #ifdef V7
    462 	if (totty) {
    463 		struct winsize win;
    464 		if (ioctl(fileno(stdout), TIOCGWINSZ, &win) != -1)
    465 			Lpp = win.ws_row;
    466 		if (Lpp <= 0) {
    467 			if (tgetent(inbuf, getenv("TERM")) <= 0
    468 			    || (Lpp = tgetnum("li")) <= 0) {
    469 				Lpp = NLINES;
    470 			}
    471 		}
    472 	}
    473 #endif
    474 	Lpp -= 6;	/* for headers, etc. */
    475 
    476 	already = NO;
    477 	prevmsg = firstmsg;
    478 	printing = YES;
    479 	if (ruptible)
    480 		signal(SIGINT, onintr);
    481 
    482 	/*
    483 	 * Main program loop
    484 	 */
    485 	for (msg = firstmsg; msg <= lastmsg; msg++) {
    486 
    487 		snprintf(fname, sizeof (fname), "%s/%d", _PATH_MSGS, msg);
    488 		newmsg = fopen(fname, "r");
    489 		if (newmsg == NULL)
    490 			continue;
    491 
    492 		gfrsub(newmsg);		/* get From and Subject fields */
    493 		if (locomode && !local) {
    494 			fclose(newmsg);
    495 			continue;
    496 		}
    497 
    498 		if (qopt) {	/* This has to be located here */
    499 			printf("There are new messages.\n");
    500 			exit(0);
    501 		}
    502 
    503 		if (already && !hdrs)
    504 			putchar('\n');
    505 
    506 		/*
    507 		 * Print header
    508 		 */
    509 		if (totty)
    510 			signal(SIGTSTP, onsusp);
    511 		(void) setjmp(tstpbuf);
    512 		already = YES;
    513 		nlines = 2;
    514 		if (seenfrom) {
    515 			printf("Message %d:\nFrom %s %s", msg, from, date);
    516 			nlines++;
    517 		}
    518 		if (seensubj) {
    519 			printf("Subject: %s", subj);
    520 			nlines++;
    521 		}
    522 		else {
    523 			if (seenfrom) {
    524 				putchar('\n');
    525 				nlines++;
    526 			}
    527 			while (nlines < 6
    528 			    && fgets(inbuf, sizeof inbuf, newmsg)
    529 			    && inbuf[0] != '\n') {
    530 				fputs(inbuf, stdout);
    531 				nlines++;
    532 			}
    533 		}
    534 
    535 		lct = linecnt(newmsg);
    536 		if (lct)
    537 			printf("(%d%slines) ", lct, seensubj? " " : " more ");
    538 
    539 		if (hdrs) {
    540 			printf("\n-----\n");
    541 			fclose(newmsg);
    542 			continue;
    543 		}
    544 
    545 		/*
    546 		 * Ask user for command
    547 		 */
    548 		if (totty)
    549 			ask(lct? MORE : (msg==lastmsg? NOMORE : NEXT));
    550 		else
    551 			inbuf[0] = 'y';
    552 		if (totty)
    553 			signal(SIGTSTP, SIG_DFL);
    554 cmnd:
    555 		in = inbuf;
    556 		switch (*in) {
    557 			case 'x':
    558 			case 'X':
    559 				exit(0);
    560 
    561 			case 'q':
    562 			case 'Q':
    563 				quitit = YES;
    564 				printf("--Postponed--\n");
    565 				exit(0);
    566 				/* intentional fall-thru */
    567 			case 'n':
    568 			case 'N':
    569 				if (msg >= nextmsg) sep = "Flushed";
    570 				prevmsg = msg;
    571 				break;
    572 
    573 			case 'p':
    574 			case 'P':
    575 				use_pager = (*in++ == 'p');
    576 				/* intentional fallthru */
    577 			case '\n':
    578 			case 'y':
    579 			default:
    580 				if (*in == '-') {
    581 					msg = prevmsg-1;
    582 					sep = "replay";
    583 					break;
    584 				}
    585 				if (isdigit((unsigned char)*in)) {
    586 					msg = next(in);
    587 					sep = in;
    588 					break;
    589 				}
    590 
    591 				prmesg(nlines + lct + (seensubj? 1 : 0));
    592 				prevmsg = msg;
    593 
    594 		}
    595 
    596 		printf("--%s--\n", sep);
    597 		sep = "-";
    598 		if (msg >= nextmsg) {
    599 			nextmsg = msg + 1;
    600 			fseek(msgsrc, 0L, 0);
    601 			fprintf(msgsrc, "%d\n", nextmsg);
    602 			fflush(msgsrc);
    603 		}
    604 		if (newmsg)
    605 			fclose(newmsg);
    606 		if (quitit)
    607 			break;
    608 	}
    609 
    610 	/*
    611 	 * Make sure .rc file gets updated
    612 	 */
    613 	if (--msg >= nextmsg) {
    614 		nextmsg = msg + 1;
    615 		fseek(msgsrc, 0L, 0);
    616 		fprintf(msgsrc, "%d\n", nextmsg);
    617 		fflush(msgsrc);
    618 	}
    619 	if (already && !quitit && lastcmd && totty) {
    620 		/*
    621 		 * save or reply to last message?
    622 		 */
    623 		msg = prevmsg;
    624 		ask(NOMORE);
    625 		if (inbuf[0] == '-' || isdigit((unsigned char)inbuf[0]))
    626 			goto cmnd;
    627 	}
    628 	if (!(already || hush || qopt))
    629 		printf("No new messages.\n");
    630 	exit(0);
    631 }
    632 
    633 void
    634 prmesg(length)
    635 	int length;
    636 {
    637 	FILE *outf;
    638 	char *env_pager;
    639 
    640 	if (use_pager && length > Lpp) {
    641 		signal(SIGPIPE, SIG_IGN);
    642 		signal(SIGQUIT, SIG_IGN);
    643                 if ((env_pager = getenv("PAGER")) == NULL ||
    644 		    env_pager[0] == '\0') {
    645                         snprintf(cmdbuf, sizeof(cmdbuf), "%s -z%d",
    646                             _PATH_PAGER, Lpp);
    647                 } else {
    648                         strlcpy(cmdbuf, env_pager, sizeof (cmdbuf));
    649                 }
    650 		outf = popen(cmdbuf, "w");
    651 		if (!outf)
    652 			outf = stdout;
    653 		else
    654 			setbuf(outf, (char *)NULL);
    655 	}
    656 	else
    657 		outf = stdout;
    658 
    659 	if (seensubj)
    660 		putc('\n', outf);
    661 
    662 	while (fgets(inbuf, sizeof inbuf, newmsg)) {
    663 		fputs(inbuf, outf);
    664 		if (ferror(outf)) {
    665 			clearerr(outf);
    666 			break;
    667 		}
    668 	}
    669 
    670 	if (outf != stdout) {
    671 		pclose(outf);
    672 		signal(SIGPIPE, SIG_DFL);
    673 		signal(SIGQUIT, SIG_DFL);
    674 	}
    675 	else {
    676 		fflush(stdout);
    677 	}
    678 
    679 	/* trick to force wait on output */
    680 	tcdrain(fileno(stdout));
    681 }
    682 
    683 void
    684 onintr(dummy)
    685 	int dummy;
    686 {
    687 	signal(SIGINT, onintr);
    688 	if (mailing)
    689 		unlink(fname);
    690 	if (sending) {
    691 		unlink(fname);
    692 		puts("--Killed--");
    693 		exit(1);
    694 	}
    695 	if (printing) {
    696 		putchar('\n');
    697 		if (hdrs)
    698 			exit(0);
    699 		sep = "Interrupt";
    700 		if (newmsg)
    701 			fseek(newmsg, 0L, 2);
    702 		intrpflg = YES;
    703 	}
    704 }
    705 
    706 /*
    707  * We have just gotten a susp.  Suspend and prepare to resume.
    708  */
    709 void
    710 onsusp(dummy)
    711 	int dummy;
    712 {
    713 
    714 	signal(SIGTSTP, SIG_DFL);
    715 	sigsetmask(0);
    716 	kill(0, SIGTSTP);
    717 	signal(SIGTSTP, onsusp);
    718 	if (!mailing)
    719 		longjmp(tstpbuf, 0);
    720 }
    721 
    722 int
    723 linecnt(f)
    724 	FILE *f;
    725 {
    726 	off_t oldpos = ftell(f);
    727 	int l = 0;
    728 	char lbuf[BUFSIZ];
    729 
    730 	while (fgets(lbuf, sizeof lbuf, f))
    731 		l++;
    732 	clearerr(f);
    733 	fseek(f, oldpos, 0);
    734 	return (l);
    735 }
    736 
    737 int
    738 next(buf)
    739 	char *buf;
    740 {
    741 	int i;
    742 	sscanf(buf, "%d", &i);
    743 	snprintf(buf, sizeof (buf), "Goto %d", i);
    744 	return(--i);
    745 }
    746 
    747 void
    748 ask(prompt)
    749 	char *prompt;
    750 {
    751 	char	inch;
    752 	int	n, cmsg;
    753 	off_t	oldpos;
    754 	FILE	*cpfrom, *cpto;
    755 
    756 	printf("%s ", prompt);
    757 	fflush(stdout);
    758 	intrpflg = NO;
    759 	(void) fgets(inbuf, sizeof inbuf, stdin);
    760 	if ((n = strlen(inbuf)) > 0 && inbuf[n - 1] == '\n')
    761 		inbuf[n - 1] = '\0';
    762 	if (intrpflg)
    763 		inbuf[0] = 'x';
    764 
    765 	/*
    766 	 * Handle 'mail' and 'save' here.
    767 	 */
    768         if (((inch = inbuf[0]) == 's' || inch == 'm') && !restricted) {
    769 		if (inbuf[1] == '-')
    770 			cmsg = prevmsg;
    771 		else if (isdigit((unsigned char)inbuf[1]))
    772 			cmsg = atoi(&inbuf[1]);
    773 		else
    774 			cmsg = msg;
    775 		snprintf(fname, sizeof (fname), "%s/%d", _PATH_MSGS, cmsg);
    776 
    777 		oldpos = ftell(newmsg);
    778 
    779 		cpfrom = fopen(fname, "r");
    780 		if (!cpfrom) {
    781 			printf("Message %d not found\n", cmsg);
    782 			ask (prompt);
    783 			return;
    784 		}
    785 
    786 		if (inch == 's') {
    787 			in = nxtfld(inbuf);
    788 			if (*in) {
    789 				for (n=0; in[n] > ' '; n++) { /* sizeof fname? */
    790 					fname[n] = in[n];
    791 				}
    792 				fname[n] = '\0';
    793 			}
    794 			else
    795 				strlcpy(fname, "Messages", sizeof(fname));
    796 		}
    797 		else {
    798 			int	fd;
    799 
    800 			strlcpy(fname, _PATH_TMP, sizeof(fname));
    801 			fd = mkstemp(fname);
    802 			if (fd == -1)
    803 				err(1, "mkstemp failed");
    804 			close(fd);
    805 			snprintf(cmdbuf, sizeof (cmdbuf), _PATH_MAIL, fname);
    806 			mailing = YES;
    807 		}
    808 		cpto = fopen(fname, "a");
    809 		if (!cpto) {
    810 			perror(fname);
    811 			mailing = NO;
    812 			fseek(newmsg, oldpos, 0);
    813 			ask(prompt);
    814 			return;
    815 		}
    816 
    817 		while ((n = fread(inbuf, 1, sizeof inbuf, cpfrom)) != 0)
    818 			fwrite(inbuf, 1, n, cpto);
    819 
    820 		fclose(cpfrom);
    821 		fclose(cpto);
    822 		fseek(newmsg, oldpos, 0);	/* reposition current message */
    823 		if (inch == 's')
    824 			printf("Message %d saved in \"%s\"\n", cmsg, fname);
    825 		else {
    826 			system(cmdbuf);
    827 			unlink(fname);
    828 			mailing = NO;
    829 		}
    830 		ask(prompt);
    831 	}
    832 }
    833 
    834 void
    835 gfrsub(infile)
    836 	FILE *infile;
    837 {
    838 	off_t frompos;
    839 
    840 	seensubj = seenfrom = NO;
    841 	local = YES;
    842 	subj[0] = from[0] = date[0] = 0;
    843 
    844 	/*
    845 	 * Is this a normal message?
    846 	 */
    847 	if (fgets(inbuf, sizeof inbuf, infile)) {
    848 		if (strncmp(inbuf, "From", 4)==0) {
    849 			/*
    850 			 * expected form starts with From
    851 			 */
    852 			seenfrom = YES;
    853 			frompos = ftell(infile);
    854 			ptr = from;
    855 			in = nxtfld(inbuf);
    856 			if (*in) while (*in && *in > ' ') {
    857 				if (*in == ':' || *in == '@' || *in == '!')
    858 					local = NO;
    859 				*ptr++ = *in++;
    860 				/* what about sizeof from ? */
    861 			}
    862 			*ptr = '\0';
    863 			if (*(in = nxtfld(in)))
    864 				strncpy(date, in, sizeof date);
    865 			else {
    866 				date[0] = '\n';
    867 				date[1] = '\0';
    868 			}
    869 		}
    870 		else {
    871 			/*
    872 			 * not the expected form
    873 			 */
    874 			fseek(infile, 0L, 0);
    875 			return;
    876 		}
    877 	}
    878 	else
    879 		/*
    880 		 * empty file ?
    881 		 */
    882 		return;
    883 
    884 	/*
    885 	 * look for Subject line until EOF or a blank line
    886 	 */
    887 	while (fgets(inbuf, sizeof inbuf, infile)
    888 	    && !(blankline = (inbuf[0] == '\n'))) {
    889 		/*
    890 		 * extract Subject line
    891 		 */
    892 		if (!seensubj && strncmp(inbuf, "Subj", 4)==0) {
    893 			seensubj = YES;
    894 			frompos = ftell(infile);
    895 			strncpy(subj, nxtfld(inbuf), sizeof subj);
    896 		}
    897 	}
    898 	if (!blankline)
    899 		/*
    900 		 * ran into EOF
    901 		 */
    902 		fseek(infile, frompos, 0);
    903 
    904 	if (!seensubj)
    905 		/*
    906 		 * for possible use with Mail
    907 		 */
    908 		strncpy(subj, "(No Subject)\n", sizeof subj);
    909 }
    910 
    911 char *
    912 nxtfld(s)
    913 	char *s;
    914 {
    915 	if (*s) while (*s && *s > ' ') s++;	/* skip over this field */
    916 	if (*s) while (*s && *s <= ' ') s++;	/* find start of next field */
    917 	return (s);
    918 }
    919