xref: /freebsd/usr.bin/mail/collect.c (revision 9b37d84c87e69dabc69d818aa4d2fea718bd8b74)
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  * Mail -- a mail program
34  *
35  * Collect input from standard input, handling
36  * ~ escapes.
37  */
38 
39 #include "rcv.h"
40 #include <fcntl.h>
41 #include "extern.h"
42 
43 /*
44  * Read a message from standard input and return a read file to it
45  * or NULL on error.
46  */
47 
48 /*
49  * The following hokiness with global variables is so that on
50  * receipt of an interrupt signal, the partial message can be salted
51  * away on dead.letter.
52  */
53 
54 static	sig_t	saveint;		/* Previous SIGINT value */
55 static	sig_t	savehup;		/* Previous SIGHUP value */
56 static	sig_t	savetstp;		/* Previous SIGTSTP value */
57 static	sig_t	savettou;		/* Previous SIGTTOU value */
58 static	sig_t	savettin;		/* Previous SIGTTIN value */
59 static	FILE	*collf;			/* File for saving away */
60 static	int	hadintr;		/* Have seen one SIGINT so far */
61 
62 static	jmp_buf	colljmp;		/* To get back to work */
63 static	int	colljmp_p;		/* whether to long jump */
64 static	jmp_buf	collabort;		/* To end collection with error */
65 
66 FILE *
67 collect(struct header *hp, int printheaders)
68 {
69 	FILE *fbuf;
70 	int lc, cc, escape, eofcount, fd, c, t;
71 	char linebuf[LINESIZE], tempname[PATHSIZE], *cp, getsub;
72 	sigset_t nset;
73 	int longline, lastlong, rc;	/* So we don't make 2 or more lines
74 					   out of a long input line. */
75 
76 	collf = NULL;
77 	/*
78 	 * Start catching signals from here, but we're still die on interrupts
79 	 * until we're in the main loop.
80 	 */
81 	(void)sigemptyset(&nset);
82 	if (value("interactive") != NULL) {
83 		(void)sigaddset(&nset, SIGINT);
84 		(void)sigaddset(&nset, SIGHUP);
85 	}
86 	(void)sigprocmask(SIG_BLOCK, &nset, NULL);
87 	if (value("interactive") != NULL) {
88 		if ((saveint = signal(SIGINT, SIG_IGN)) != SIG_IGN)
89 			(void)signal(SIGINT, collint);
90 		if ((savehup = signal(SIGHUP, SIG_IGN)) != SIG_IGN)
91 			(void)signal(SIGHUP, collhup);
92 		savetstp = signal(SIGTSTP, collstop);
93 		savettou = signal(SIGTTOU, collstop);
94 		savettin = signal(SIGTTIN, collstop);
95 	}
96 	if (setjmp(collabort) || setjmp(colljmp)) {
97 		(void)rm(tempname);
98 		goto err;
99 	}
100 	(void)sigprocmask(SIG_UNBLOCK, &nset, NULL);
101 
102 	noreset++;
103 	(void)snprintf(tempname, sizeof(tempname),
104 	    "%s/mail.RsXXXXXXXXXX", tmpdir);
105 	if ((fd = mkstemp(tempname)) == -1 ||
106 	    (collf = Fdopen(fd, "w+")) == NULL) {
107 		warn("%s", tempname);
108 		goto err;
109 	}
110 	(void)rm(tempname);
111 
112 	/*
113 	 * If we are going to prompt for a subject,
114 	 * refrain from printing a newline after
115 	 * the headers (since some people mind).
116 	 */
117 	t = GTO|GSUBJECT|GCC|GNL;
118 	getsub = 0;
119 	if (hp->h_subject == NULL && value("interactive") != NULL &&
120 	    (value("ask") != NULL || value("asksub") != NULL))
121 		t &= ~GNL, getsub++;
122 	if (printheaders) {
123 		puthead(hp, stdout, t);
124 		(void)fflush(stdout);
125 	}
126 	if ((cp = value("escape")) != NULL)
127 		escape = *cp;
128 	else
129 		escape = ESCAPE;
130 	eofcount = 0;
131 	hadintr = 0;
132 	longline = 0;
133 
134 	if (!setjmp(colljmp)) {
135 		if (getsub)
136 			grabh(hp, GSUBJECT);
137 	} else {
138 		/*
139 		 * Come here for printing the after-signal message.
140 		 * Duplicate messages won't be printed because
141 		 * the write is aborted if we get a SIGTTOU.
142 		 */
143 cont:
144 		if (hadintr) {
145 			(void)fflush(stdout);
146 			fprintf(stderr,
147 			"\n(Interrupt -- one more to kill letter)\n");
148 		} else {
149 			printf("(continue)\n");
150 			(void)fflush(stdout);
151 		}
152 	}
153 	for (;;) {
154 		colljmp_p = 1;
155 		c = readline(stdin, linebuf, LINESIZE);
156 		colljmp_p = 0;
157 		if (c < 0) {
158 			if (value("interactive") != NULL &&
159 			    value("ignoreeof") != NULL && ++eofcount < 25) {
160 				printf("Use \".\" to terminate letter\n");
161 				continue;
162 			}
163 			break;
164 		}
165 		lastlong = longline;
166 		longline = c == LINESIZE - 1;
167 		eofcount = 0;
168 		hadintr = 0;
169 		if (linebuf[0] == '.' && linebuf[1] == '\0' &&
170 		    value("interactive") != NULL && !lastlong &&
171 		    (value("dot") != NULL || value("ignoreeof") != NULL))
172 			break;
173 		if (linebuf[0] != escape || value("interactive") == NULL ||
174 		    lastlong) {
175 			if (putline(collf, linebuf, !longline) < 0)
176 				goto err;
177 			continue;
178 		}
179 		c = linebuf[1];
180 		switch (c) {
181 		default:
182 			/*
183 			 * On double escape, just send the single one.
184 			 * Otherwise, it's an error.
185 			 */
186 			if (c == escape) {
187 				if (putline(collf, &linebuf[1], !longline) < 0)
188 					goto err;
189 				else
190 					break;
191 			}
192 			printf("Unknown tilde escape.\n");
193 			break;
194 		case 'C':
195 			/*
196 			 * Dump core.
197 			 */
198 			core(NULL);
199 			break;
200 		case '!':
201 			/*
202 			 * Shell escape, send the balance of the
203 			 * line to sh -c.
204 			 */
205 			shell(&linebuf[2]);
206 			break;
207 		case ':':
208 		case '_':
209 			/*
210 			 * Escape to command mode, but be nice!
211 			 */
212 			execute(&linebuf[2], 1);
213 			goto cont;
214 		case '.':
215 			/*
216 			 * Simulate end of file on input.
217 			 */
218 			goto out;
219 		case 'q':
220 			/*
221 			 * Force a quit of sending mail.
222 			 * Act like an interrupt happened.
223 			 */
224 			hadintr++;
225 			collint(SIGINT);
226 			exit(1);
227 		case 'x':
228 			/*
229 			 * Exit, do not save in dead.letter.
230 			 */
231 			goto err;
232 		case 'h':
233 			/*
234 			 * Grab a bunch of headers.
235 			 */
236 			grabh(hp, GTO|GSUBJECT|GCC|GBCC);
237 			goto cont;
238 		case 't':
239 			/*
240 			 * Add to the To list.
241 			 */
242 			hp->h_to = cat(hp->h_to, extract(&linebuf[2], GTO));
243 			break;
244 		case 's':
245 			/*
246 			 * Set the Subject line.
247 			 */
248 			cp = &linebuf[2];
249 			while (isspace((unsigned char)*cp))
250 				cp++;
251 			hp->h_subject = savestr(cp);
252 			break;
253 		case 'R':
254 			/*
255 			 * Set the Reply-To line.
256 			 */
257 			cp = &linebuf[2];
258 			while (isspace((unsigned char)*cp))
259 				cp++;
260 			hp->h_replyto = savestr(cp);
261 			break;
262 		case 'c':
263 			/*
264 			 * Add to the CC list.
265 			 */
266 			hp->h_cc = cat(hp->h_cc, extract(&linebuf[2], GCC));
267 			break;
268 		case 'b':
269 			/*
270 			 * Add to the BCC list.
271 			 */
272 			hp->h_bcc = cat(hp->h_bcc, extract(&linebuf[2], GBCC));
273 			break;
274 		case 'i':
275 		case 'A':
276 		case 'a':
277 			/*
278 			 * Insert named variable in message.
279 			 */
280 			switch(c) {
281 				case 'i':
282 					cp = &linebuf[2];
283 					while(isspace((unsigned char)*cp))
284 						cp++;
285 					break;
286 				case 'a':
287 					cp = "sign";
288 					break;
289 				case 'A':
290 					cp = "Sign";
291 					break;
292 				default:
293 					goto err;
294 			}
295 
296 			if(*cp != '\0' && (cp = value(cp)) != NULL) {
297 				printf("%s\n", cp);
298 				if(putline(collf, cp, 1) < 0)
299 					goto err;
300 			}
301 
302 			break;
303 		case 'd':
304 			/*
305 			 * Read in the dead letter file.
306 			 */
307 			if (strlcpy(linebuf + 2, getdeadletter(),
308 				sizeof(linebuf) - 2)
309 			    >= sizeof(linebuf) - 2) {
310 				printf("Line buffer overflow\n");
311 				break;
312 			}
313 			/* FALLTHROUGH */
314 		case 'r':
315 		case '<':
316 			/*
317 			 * Invoke a file:
318 			 * Search for the file name,
319 			 * then open it and copy the contents to collf.
320 			 */
321 			cp = &linebuf[2];
322 			while (isspace((unsigned char)*cp))
323 				cp++;
324 			if (*cp == '\0') {
325 				printf("Interpolate what file?\n");
326 				break;
327 			}
328 			cp = expand(cp);
329 			if (cp == NULL)
330 				break;
331 			if (*cp == '!') {
332 				/*
333 				 * Insert stdout of command.
334 				 */
335 				char *sh;
336 				int nullfd, tempfd, rc;
337 				char tempname2[PATHSIZE];
338 
339 				if ((nullfd = open(_PATH_DEVNULL, O_RDONLY, 0))
340 				    == -1) {
341 					warn(_PATH_DEVNULL);
342 					break;
343 				}
344 
345 				(void)snprintf(tempname2, sizeof(tempname2),
346 				    "%s/mail.ReXXXXXXXXXX", tmpdir);
347 				if ((tempfd = mkstemp(tempname2)) == -1 ||
348 				    (fbuf = Fdopen(tempfd, "w+")) == NULL) {
349 					warn("%s", tempname2);
350 					break;
351 				}
352 				(void)unlink(tempname2);
353 
354 				if ((sh = value("SHELL")) == NULL)
355 					sh = _PATH_CSHELL;
356 
357 				rc = run_command(sh, 0, nullfd, fileno(fbuf),
358 				    "-c", cp+1, NULL);
359 
360 				close(nullfd);
361 
362 				if (rc < 0) {
363 					(void)Fclose(fbuf);
364 					break;
365 				}
366 
367 				if (fsize(fbuf) == 0) {
368 					fprintf(stderr,
369 					    "No bytes from command \"%s\"\n",
370 					    cp+1);
371 					(void)Fclose(fbuf);
372 					break;
373 				}
374 
375 				rewind(fbuf);
376 			} else if (isdir(cp)) {
377 				printf("%s: Directory\n", cp);
378 				break;
379 			} else if ((fbuf = Fopen(cp, "r")) == NULL) {
380 				warn("%s", cp);
381 				break;
382 			}
383 			printf("\"%s\" ", cp);
384 			(void)fflush(stdout);
385 			lc = 0;
386 			cc = 0;
387 			while ((rc = readline(fbuf, linebuf, LINESIZE)) >= 0) {
388 				if (rc != LINESIZE - 1)
389 					lc++;
390 				if ((t = putline(collf, linebuf,
391 					 rc != LINESIZE - 1)) < 0) {
392 					(void)Fclose(fbuf);
393 					goto err;
394 				}
395 				cc += t;
396 			}
397 			(void)Fclose(fbuf);
398 			printf("%d/%d\n", lc, cc);
399 			break;
400 		case 'w':
401 			/*
402 			 * Write the message on a file.
403 			 */
404 			cp = &linebuf[2];
405 			while (*cp == ' ' || *cp == '\t')
406 				cp++;
407 			if (*cp == '\0') {
408 				fprintf(stderr, "Write what file!?\n");
409 				break;
410 			}
411 			if ((cp = expand(cp)) == NULL)
412 				break;
413 			rewind(collf);
414 			exwrite(cp, collf, 1);
415 			break;
416 		case 'm':
417 		case 'M':
418 		case 'f':
419 		case 'F':
420 			/*
421 			 * Interpolate the named messages, if we
422 			 * are in receiving mail mode.  Does the
423 			 * standard list processing garbage.
424 			 * If ~f is given, we don't shift over.
425 			 */
426 			if (forward(linebuf + 2, collf, tempname, c) < 0)
427 				goto err;
428 			goto cont;
429 		case '?':
430 			if ((fbuf = Fopen(_PATH_TILDE, "r")) == NULL) {
431 				warn("%s", _PATH_TILDE);
432 				break;
433 			}
434 			while ((t = getc(fbuf)) != EOF)
435 				(void)putchar(t);
436 			(void)Fclose(fbuf);
437 			break;
438 		case 'p':
439 			/*
440 			 * Print out the current state of the
441 			 * message without altering anything.
442 			 */
443 			rewind(collf);
444 			printf("-------\nMessage contains:\n");
445 			puthead(hp, stdout, GTO|GSUBJECT|GCC|GBCC|GNL);
446 			while ((t = getc(collf)) != EOF)
447 				(void)putchar(t);
448 			goto cont;
449 		case '|':
450 			/*
451 			 * Pipe message through command.
452 			 * Collect output as new message.
453 			 */
454 			rewind(collf);
455 			mespipe(collf, &linebuf[2]);
456 			goto cont;
457 		case 'v':
458 		case 'e':
459 			/*
460 			 * Edit the current message.
461 			 * 'e' means to use EDITOR
462 			 * 'v' means to use VISUAL
463 			 */
464 			rewind(collf);
465 			mesedit(collf, c);
466 			goto cont;
467 		}
468 	}
469 	goto out;
470 err:
471 	if (collf != NULL) {
472 		(void)Fclose(collf);
473 		collf = NULL;
474 	}
475 out:
476 	if (collf != NULL)
477 		rewind(collf);
478 	noreset--;
479 	(void)sigprocmask(SIG_BLOCK, &nset, NULL);
480 	if (value("interactive") != NULL) {
481 		(void)signal(SIGINT, saveint);
482 		(void)signal(SIGHUP, savehup);
483 		(void)signal(SIGTSTP, savetstp);
484 		(void)signal(SIGTTOU, savettou);
485 		(void)signal(SIGTTIN, savettin);
486 	}
487 	(void)sigprocmask(SIG_UNBLOCK, &nset, NULL);
488 	return (collf);
489 }
490 
491 /*
492  * Write a file, ex-like if f set.
493  */
494 int
495 exwrite(char name[], FILE *fp, int f)
496 {
497 	FILE *of;
498 	int c, lc;
499 	long cc;
500 	struct stat junk;
501 
502 	if (f) {
503 		printf("\"%s\" ", name);
504 		(void)fflush(stdout);
505 	}
506 	if (stat(name, &junk) >= 0 && S_ISREG(junk.st_mode)) {
507 		if (!f)
508 			fprintf(stderr, "%s: ", name);
509 		fprintf(stderr, "File exists\n");
510 		return (-1);
511 	}
512 	if ((of = Fopen(name, "w")) == NULL) {
513 		warn((char *)NULL);
514 		return (-1);
515 	}
516 	lc = 0;
517 	cc = 0;
518 	while ((c = getc(fp)) != EOF) {
519 		cc++;
520 		if (c == '\n')
521 			lc++;
522 		(void)putc(c, of);
523 		if (ferror(of)) {
524 			warnx("%s", name);
525 			(void)Fclose(of);
526 			return (-1);
527 		}
528 	}
529 	(void)Fclose(of);
530 	printf("%d/%ld\n", lc, cc);
531 	(void)fflush(stdout);
532 	return (0);
533 }
534 
535 /*
536  * Edit the message being collected on fp.
537  * On return, make the edit file the new temp file.
538  */
539 void
540 mesedit(FILE *fp, int c)
541 {
542 	sig_t sigint = signal(SIGINT, SIG_IGN);
543 	FILE *nf = run_editor(fp, (off_t)-1, c, 0);
544 
545 	if (nf != NULL) {
546 		(void)fseeko(nf, (off_t)0, SEEK_END);
547 		collf = nf;
548 		(void)Fclose(fp);
549 	}
550 	(void)signal(SIGINT, sigint);
551 }
552 
553 /*
554  * Pipe the message through the command.
555  * Old message is on stdin of command;
556  * New message collected from stdout.
557  * Sh -c must return 0 to accept the new message.
558  */
559 void
560 mespipe(FILE *fp, char cmd[])
561 {
562 	FILE *nf;
563 	int fd;
564 	sig_t sigint = signal(SIGINT, SIG_IGN);
565 	char *sh, tempname[PATHSIZE];
566 
567 	(void)snprintf(tempname, sizeof(tempname),
568 	    "%s/mail.ReXXXXXXXXXX", tmpdir);
569 	if ((fd = mkstemp(tempname)) == -1 ||
570 	    (nf = Fdopen(fd, "w+")) == NULL) {
571 		warn("%s", tempname);
572 		goto out;
573 	}
574 	(void)rm(tempname);
575 	/*
576 	 * stdin = current message.
577 	 * stdout = new message.
578 	 */
579 	if ((sh = value("SHELL")) == NULL)
580 		sh = _PATH_CSHELL;
581 	if (run_command(sh,
582 	    0, fileno(fp), fileno(nf), "-c", cmd, NULL) < 0) {
583 		(void)Fclose(nf);
584 		goto out;
585 	}
586 	if (fsize(nf) == 0) {
587 		fprintf(stderr, "No bytes from \"%s\" !?\n", cmd);
588 		(void)Fclose(nf);
589 		goto out;
590 	}
591 	/*
592 	 * Take new files.
593 	 */
594 	(void)fseeko(nf, (off_t)0, SEEK_END);
595 	collf = nf;
596 	(void)Fclose(fp);
597 out:
598 	(void)signal(SIGINT, sigint);
599 }
600 
601 /*
602  * Interpolate the named messages into the current
603  * message, preceding each line with a tab.
604  * Return a count of the number of characters now in
605  * the message, or -1 if an error is encountered writing
606  * the message temporary.  The flag argument is 'm' if we
607  * should shift over and 'f' if not.
608  */
609 int
610 forward(char ms[], FILE *fp, char *fn, int f)
611 {
612 	int *msgvec;
613 	struct ignoretab *ig;
614 	char *tabst;
615 
616 	msgvec = (int *)salloc((msgCount+1) * sizeof(*msgvec));
617 	if (msgvec == NULL)
618 		return (0);
619 	if (getmsglist(ms, msgvec, 0) < 0)
620 		return (0);
621 	if (*msgvec == 0) {
622 		*msgvec = first(0, MMNORM);
623 		if (*msgvec == 0) {
624 			printf("No appropriate messages\n");
625 			return (0);
626 		}
627 		msgvec[1] = 0;
628 	}
629 	if (f == 'f' || f == 'F')
630 		tabst = NULL;
631 	else if ((tabst = value("indentprefix")) == NULL)
632 		tabst = "\t";
633 	ig = isupper((unsigned char)f) ? NULL : ignore;
634 	printf("Interpolating:");
635 	for (; *msgvec != 0; msgvec++) {
636 		struct message *mp = message + *msgvec - 1;
637 
638 		touch(mp);
639 		printf(" %d", *msgvec);
640 		if (sendmessage(mp, fp, ig, tabst) < 0) {
641 			warnx("%s", fn);
642 			return (-1);
643 		}
644 	}
645 	printf("\n");
646 	return (0);
647 }
648 
649 /*
650  * Print (continue) when continued after ^Z.
651  */
652 /*ARGSUSED*/
653 void
654 collstop(int s)
655 {
656 	sig_t old_action = signal(s, SIG_DFL);
657 	sigset_t nset;
658 
659 	(void)sigemptyset(&nset);
660 	(void)sigaddset(&nset, s);
661 	(void)sigprocmask(SIG_UNBLOCK, &nset, NULL);
662 	(void)kill(0, s);
663 	(void)sigprocmask(SIG_BLOCK, &nset, NULL);
664 	(void)signal(s, old_action);
665 	if (colljmp_p) {
666 		colljmp_p = 0;
667 		hadintr = 0;
668 		longjmp(colljmp, 1);
669 	}
670 }
671 
672 /*
673  * On interrupt, come here to save the partial message in ~/dead.letter.
674  * Then jump out of the collection loop.
675  */
676 /*ARGSUSED*/
677 void
678 collint(int s __unused)
679 {
680 	/*
681 	 * the control flow is subtle, because we can be called from ~q.
682 	 */
683 	if (!hadintr) {
684 		if (value("ignore") != NULL) {
685 			printf("@");
686 			(void)fflush(stdout);
687 			clearerr(stdin);
688 			return;
689 		}
690 		hadintr = 1;
691 		longjmp(colljmp, 1);
692 	}
693 	rewind(collf);
694 	if (value("nosave") == NULL)
695 		savedeadletter(collf);
696 	longjmp(collabort, 1);
697 }
698 
699 /*ARGSUSED*/
700 void
701 collhup(int signo)
702 {
703 	rewind(collf);
704 	savedeadletter(collf);
705 	/*
706 	 * Let's pretend nobody else wants to clean up,
707 	 * a true statement at this time.
708 	 */
709 	signal(signo, SIG_DFL);
710 	raise(signo);
711 }
712 
713 void
714 savedeadletter(FILE *fp)
715 {
716 	FILE *dbuf;
717 	int c;
718 	char *cp;
719 
720 	if (fsize(fp) == 0)
721 		return;
722 	cp = getdeadletter();
723 	c = umask(077);
724 	dbuf = Fopen(cp, "a");
725 	(void)umask(c);
726 	if (dbuf == NULL)
727 		return;
728 	while ((c = getc(fp)) != EOF)
729 		(void)putc(c, dbuf);
730 	(void)Fclose(dbuf);
731 	rewind(fp);
732 }
733