xref: /netbsd-src/usr.bin/mail/support.c (revision aaf4ece63a859a04e37cf3a7229b5fab0157cc06)
1 /*	$NetBSD: support.c,v 1.14 2005/07/19 23:07:10 christos 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. 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 #include <sys/cdefs.h>
33 #ifndef lint
34 #if 0
35 static char sccsid[] = "@(#)aux.c	8.1 (Berkeley) 6/6/93";
36 #else
37 __RCSID("$NetBSD: support.c,v 1.14 2005/07/19 23:07:10 christos Exp $");
38 #endif
39 #endif /* not lint */
40 
41 #include "rcv.h"
42 #include "extern.h"
43 
44 /*
45  * Mail -- a mail program
46  *
47  * Auxiliary functions.
48  */
49 static char *save2str(char *, char *);
50 
51 /*
52  * Return a pointer to a dynamic copy of the argument.
53  */
54 char *
55 savestr(const char *str)
56 {
57 	char *new;
58 	size_t size = strlen(str) + 1;
59 
60 	if ((new = salloc(size)) != NULL)
61 		(void)memmove(new, str, size);
62 	return new;
63 }
64 
65 /*
66  * Make a copy of new argument incorporating old one.
67  */
68 static char *
69 save2str(char *str, char *old)
70 {
71 	char *new;
72 	size_t newsize = strlen(str) + 1;
73 	size_t oldsize = old ? strlen(old) + 1 : 0;
74 
75 	if ((new = salloc(newsize + oldsize)) != NULL) {
76 		if (oldsize) {
77 			(void)memmove(new, old, oldsize);
78 			new[oldsize - 1] = ' ';
79 		}
80 		(void)memmove(new + oldsize, str, newsize);
81 	}
82 	return new;
83 }
84 
85 /*
86  * Touch the named message by setting its MTOUCH flag.
87  * Touched messages have the effect of not being sent
88  * back to the system mailbox on exit.
89  */
90 void
91 touch(struct message *mp)
92 {
93 
94 	mp->m_flag |= MTOUCH;
95 	if ((mp->m_flag & MREAD) == 0)
96 		mp->m_flag |= MREAD|MSTATUS;
97 }
98 
99 /*
100  * Test to see if the passed file name is a directory.
101  * Return true if it is.
102  */
103 int
104 isdir(const char name[])
105 {
106 	struct stat sbuf;
107 
108 	if (stat(name, &sbuf) < 0)
109 		return(0);
110 	return (S_ISDIR(sbuf.st_mode));
111 }
112 
113 /*
114  * Count the number of arguments in the given string raw list.
115  */
116 int
117 argcount(char **argv)
118 {
119 	char **ap;
120 
121 	for (ap = argv; *ap++ != NULL;)
122 		;
123 	return ap - argv - 1;
124 }
125 
126 /*
127  * Return the desired header line from the passed message
128  * pointer (or NULL if the desired header field is not available).
129  */
130 char *
131 hfield(const char field[], const struct message *mp)
132 {
133 	FILE *ibuf;
134 	char linebuf[LINESIZE];
135 	int lc;
136 	char *headerfield;
137 	char *colon, *oldhfield = NULL;
138 
139 	ibuf = setinput(mp);
140 	if ((lc = mp->m_lines - 1) < 0)
141 		return NULL;
142 	if (readline(ibuf, linebuf, LINESIZE) < 0)
143 		return NULL;
144 	while (lc > 0) {
145 		if ((lc = gethfield(ibuf, linebuf, lc, &colon)) < 0)
146 			return oldhfield;
147 		if ((headerfield = ishfield(linebuf, colon, field)) != NULL)
148 			oldhfield = save2str(headerfield, oldhfield);
149 	}
150 	return oldhfield;
151 }
152 
153 /*
154  * Return the next header field found in the given message.
155  * Return >= 0 if something found, < 0 elsewise.
156  * "colon" is set to point to the colon in the header.
157  * Must deal with \ continuations & other such fraud.
158  */
159 int
160 gethfield(FILE *f, char linebuf[], int rem, char **colon)
161 {
162 	char line2[LINESIZE];
163 	char *cp, *cp2;
164 	int c;
165 
166 	for (;;) {
167 		if (--rem < 0)
168 			return -1;
169 		if ((c = readline(f, linebuf, LINESIZE)) <= 0)
170 			return -1;
171 		for (cp = linebuf; isprint((unsigned char)*cp) && *cp != ' ' && *cp != ':';
172 		     cp++)
173 			;
174 		if (*cp != ':' || cp == linebuf)
175 			continue;
176 		/*
177 		 * I guess we got a headline.
178 		 * Handle wraparounding
179 		 */
180 		*colon = cp;
181 		cp = linebuf + c;
182 		for (;;) {
183 			while (--cp >= linebuf && (*cp == ' ' || *cp == '\t'))
184 				;
185 			cp++;
186 			if (rem <= 0)
187 				break;
188 			(void)ungetc(c = getc(f), f);
189 			if (c != ' ' && c != '\t')
190 				break;
191 			if ((c = readline(f, line2, LINESIZE)) < 0)
192 				break;
193 			rem--;
194 			for (cp2 = line2; *cp2 == ' ' || *cp2 == '\t'; cp2++)
195 				;
196 			c -= cp2 - line2;
197 			if (cp + c >= linebuf + LINESIZE - 2)
198 				break;
199 			*cp++ = ' ';
200 			(void)memmove(cp, cp2, (size_t)c);
201 			cp += c;
202 		}
203 		*cp = 0;
204 		return rem;
205 	}
206 	/* NOTREACHED */
207 }
208 
209 /*
210  * Check whether the passed line is a header line of
211  * the desired breed.  Return the field body, or 0.
212  */
213 
214 char*
215 ishfield(const char linebuf[], char *colon, const char field[])
216 {
217 	char *cp = colon;
218 
219 	*cp = 0;
220 	if (strcasecmp(linebuf, field) != 0) {
221 		*cp = ':';
222 		return 0;
223 	}
224 	*cp = ':';
225 	for (cp++; *cp == ' ' || *cp == '\t'; cp++)
226 		;
227 	return cp;
228 }
229 
230 /*
231  * Copy a string, lowercasing it as we go.
232  */
233 void
234 istrcpy(char *dest, const char *src)
235 {
236 
237 	do {
238 		*dest++ = tolower((unsigned char)*src);
239 	} while (*src++ != 0);
240 }
241 
242 /*
243  * The following code deals with input stacking to do source
244  * commands.  All but the current file pointer are saved on
245  * the stack.
246  */
247 
248 static	int	ssp;			/* Top of file stack */
249 struct sstack {
250 	FILE	*s_file;		/* File we were in. */
251 	int	s_cond;			/* Saved state of conditionals */
252 	int	s_loading;		/* Loading .mailrc, etc. */
253 } sstack[NOFILE];
254 
255 /*
256  * Pushdown current input file and switch to a new one.
257  * Set the global flag "sourcing" so that others will realize
258  * that they are no longer reading from a tty (in all probability).
259  */
260 int
261 source(void *v)
262 {
263 	char **arglist = v;
264 	FILE *fi;
265 	const char *cp;
266 
267 	if ((cp = expand(*arglist)) == NULL)
268 		return(1);
269 	if ((fi = Fopen(cp, "r")) == NULL) {
270 		warn("%s", cp);
271 		return(1);
272 	}
273 	if (ssp >= NOFILE - 1) {
274 		(void)printf("Too much \"sourcing\" going on.\n");
275 		(void)Fclose(fi);
276 		return(1);
277 	}
278 	sstack[ssp].s_file = input;
279 	sstack[ssp].s_cond = cond;
280 	sstack[ssp].s_loading = loading;
281 	ssp++;
282 	loading = 0;
283 	cond = CANY;
284 	input = fi;
285 	sourcing++;
286 	return(0);
287 }
288 
289 /*
290  * Pop the current input back to the previous level.
291  * Update the "sourcing" flag as appropriate.
292  */
293 int
294 unstack(void)
295 {
296 	if (ssp <= 0) {
297 		(void)printf("\"Source\" stack over-pop.\n");
298 		sourcing = 0;
299 		return(1);
300 	}
301 	(void)Fclose(input);
302 	if (cond != CANY)
303 		(void)printf("Unmatched \"if\"\n");
304 	ssp--;
305 	cond = sstack[ssp].s_cond;
306 	loading = sstack[ssp].s_loading;
307 	input = sstack[ssp].s_file;
308 	if (ssp == 0)
309 		sourcing = loading;
310 	return(0);
311 }
312 
313 /*
314  * Touch the indicated file.
315  * This is nifty for the shell.
316  */
317 void
318 alter(char *name)
319 {
320 	struct stat sb;
321 	struct timeval tv[2];
322 
323 	if (stat(name, &sb))
324 		return;
325 	(void)gettimeofday(&tv[0], NULL);
326 	tv[0].tv_sec++;
327 	TIMESPEC_TO_TIMEVAL(&tv[1], &sb.st_mtimespec);
328 	(void)utimes(name, tv);
329 }
330 
331 /*
332  * Examine the passed line buffer and
333  * return true if it is all blanks and tabs.
334  */
335 int
336 blankline(char linebuf[])
337 {
338 	char *cp;
339 
340 	for (cp = linebuf; *cp; cp++)
341 		if (*cp != ' ' && *cp != '\t')
342 			return(0);
343 	return(1);
344 }
345 
346 /*
347  * Get sender's name from this message.  If the message has
348  * a bunch of arpanet stuff in it, we may have to skin the name
349  * before returning it.
350  */
351 char *
352 nameof(struct message *mp, int reptype)
353 {
354 	char *cp, *cp2;
355 
356 	cp = skin(name1(mp, reptype));
357 	if (reptype != 0 || charcount(cp, '!') < 2)
358 		return(cp);
359 	cp2 = strrchr(cp, '!');
360 	cp2--;
361 	while (cp2 > cp && *cp2 != '!')
362 		cp2--;
363 	if (*cp2 == '!')
364 		return(cp2 + 1);
365 	return(cp);
366 }
367 
368 /*
369  * Start of a "comment".
370  * Ignore it.
371  */
372 char *
373 skip_comment(char *cp)
374 {
375 	int nesting = 1;
376 
377 	for (; nesting > 0 && *cp; cp++) {
378 		switch (*cp) {
379 		case '\\':
380 			if (cp[1])
381 				cp++;
382 			break;
383 		case '(':
384 			nesting++;
385 			break;
386 		case ')':
387 			nesting--;
388 			break;
389 		}
390 	}
391 	return cp;
392 }
393 
394 /*
395  * Skin an arpa net address according to the RFC 822 interpretation
396  * of "host-phrase."
397  */
398 char *
399 skin(char *name)
400 {
401 	int c;
402 	char *cp, *cp2;
403 	char *bufend;
404 	int gotlt, lastsp;
405 	char nbuf[BUFSIZ];
406 
407 	if (name == NULL)
408 		return(NULL);
409 	if (strchr(name, '(') == NULL && strchr(name, '<') == NULL
410 	    && strchr(name, ' ') == NULL)
411 		return(name);
412 	gotlt = 0;
413 	lastsp = 0;
414 	bufend = nbuf;
415 	for (cp = name, cp2 = bufend; (c = *cp++) != '\0'; ) {
416 		switch (c) {
417 		case '(':
418 			cp = skip_comment(cp);
419 			lastsp = 0;
420 			break;
421 
422 		case '"':
423 			/*
424 			 * Start of a "quoted-string".
425 			 * Copy it in its entirety.
426 			 */
427 			while ((c = *cp) != '\0') {
428 				cp++;
429 				if (c == '"')
430 					break;
431 				if (c != '\\')
432 					*cp2++ = c;
433 				else if ((c = *cp) != '\0') {
434 					*cp2++ = c;
435 					cp++;
436 				}
437 			}
438 			lastsp = 0;
439 			break;
440 
441 		case ' ':
442 			if (cp[0] == 'a' && cp[1] == 't' && cp[2] == ' ')
443 				cp += 3, *cp2++ = '@';
444 			else
445 			if (cp[0] == '@' && cp[1] == ' ')
446 				cp += 2, *cp2++ = '@';
447 			else
448 				lastsp = 1;
449 			break;
450 
451 		case '<':
452 			cp2 = bufend;
453 			gotlt++;
454 			lastsp = 0;
455 			break;
456 
457 		case '>':
458 			if (gotlt) {
459 				gotlt = 0;
460 				while ((c = *cp) && c != ',') {
461 					cp++;
462 					if (c == '(')
463 						cp = skip_comment(cp);
464 					else if (c == '"')
465 						while ((c = *cp) != '\0') {
466 							cp++;
467 							if (c == '"')
468 								break;
469 							if (c == '\\' && *cp)
470 								cp++;
471 						}
472 				}
473 				lastsp = 0;
474 				break;
475 			}
476 			/* FALLTHROUGH */
477 
478 		default:
479 			if (lastsp) {
480 				lastsp = 0;
481 				*cp2++ = ' ';
482 			}
483 			*cp2++ = c;
484 			if (c == ',' && !gotlt) {
485 				*cp2++ = ' ';
486 				for (; *cp == ' '; cp++)
487 					;
488 				lastsp = 0;
489 				bufend = cp2;
490 			}
491 		}
492 	}
493 	*cp2 = 0;
494 
495 	return(savestr(nbuf));
496 }
497 
498 /*
499  * Fetch the sender's name from the passed message.
500  * Reptype can be
501  *	0 -- get sender's name for display purposes
502  *	1 -- get sender's name for reply
503  *	2 -- get sender's name for Reply
504  */
505 char *
506 name1(struct message *mp, int reptype)
507 {
508 	char namebuf[LINESIZE];
509 	char linebuf[LINESIZE];
510 	char *cp, *cp2;
511 	FILE *ibuf;
512 	int firstrun = 1;
513 
514 	if ((cp = hfield("from", mp)) != NULL)
515 		return cp;
516 	if (reptype == 0 && (cp = hfield("sender", mp)) != NULL)
517 		return cp;
518 	ibuf = setinput(mp);
519 	namebuf[0] = '\0';
520 	if (readline(ibuf, linebuf, LINESIZE) < 0)
521 		return(savestr(namebuf));
522 newname:
523 	for (cp = linebuf; *cp && *cp != ' '; cp++)
524 		;
525 	for (; *cp == ' ' || *cp == '\t'; cp++)
526 		;
527 	for (cp2 = &namebuf[strlen(namebuf)];
528 	     *cp && *cp != ' ' && *cp != '\t' && cp2 < namebuf + LINESIZE - 1;)
529 		*cp2++ = *cp++;
530 	*cp2 = '\0';
531 	if (readline(ibuf, linebuf, LINESIZE) < 0)
532 		return(savestr(namebuf));
533 	if ((cp = strchr(linebuf, 'F')) == NULL)
534 		return(savestr(namebuf));
535 	if (strncmp(cp, "From", 4) != 0)
536 		return(savestr(namebuf));
537 	while ((cp = strchr(cp, 'r')) != NULL) {
538 		if (strncmp(cp, "remote", 6) == 0) {
539 			if ((cp = strchr(cp, 'f')) == NULL)
540 				break;
541 			if (strncmp(cp, "from", 4) != 0)
542 				break;
543 			if ((cp = strchr(cp, ' ')) == NULL)
544 				break;
545 			cp++;
546 			if (firstrun) {
547 				cp2 = namebuf;
548 				firstrun = 0;
549 			} else
550 				cp2 = strrchr(namebuf, '!') + 1;
551 			while (*cp && cp2 < namebuf + LINESIZE - 1)
552 				*cp2++ = *cp++;
553 			if (cp2 < namebuf + LINESIZE - 1)
554 				*cp2++ = '!';
555 			*cp2 = '\0';
556 			if (cp2 < namebuf + LINESIZE - 1)
557 				goto newname;
558 			else
559 				break;
560 		}
561 		cp++;
562 	}
563 	return(savestr(namebuf));
564 }
565 
566 /*
567  * Count the occurances of c in str
568  */
569 int
570 charcount(char *str, int c)
571 {
572 	char *cp;
573 	int i;
574 
575 	for (i = 0, cp = str; *cp; cp++)
576 		if (*cp == c)
577 			i++;
578 	return(i);
579 }
580 
581 /*
582  * Convert c to upper case
583  */
584 int
585 upcase(int c)
586 {
587 
588 	if (islower(c))
589 		return toupper(c);
590 	return c;
591 }
592 
593 /*
594  * Copy s1 to s2, return pointer to null in s2.
595  */
596 char *
597 copy(char *s1, char *s2)
598 {
599 
600 	while ((*s2++ = *s1++) != '\0')
601 		;
602 	return s2 - 1;
603 }
604 
605 /*
606  * See if the given header field is supposed to be ignored.
607  */
608 int
609 isign(const char *field, struct ignoretab ignoretabs[2])
610 {
611 	char realfld[LINESIZE];
612 
613 	if (ignoretabs == ignoreall)
614 		return 1;
615 	/*
616 	 * Lower-case the string, so that "Status" and "status"
617 	 * will hash to the same place.
618 	 */
619 	istrcpy(realfld, field);
620 	if (ignoretabs[1].i_count > 0)
621 		return (!member(realfld, ignoretabs + 1));
622 	else
623 		return (member(realfld, ignoretabs));
624 }
625 
626 int
627 member(char *realfield, struct ignoretab *table)
628 {
629 	struct ignore *igp;
630 
631 	for (igp = table->i_head[hash(realfield)]; igp != 0; igp = igp->i_link)
632 		if (*igp->i_field == *realfield &&
633 		    equal(igp->i_field, realfield))
634 			return (1);
635 	return (0);
636 }
637