xref: /netbsd-src/usr.bin/mail/fio.c (revision deb6f0161a9109e7de9b519dc8dfb9478668dcdd)
1 /*	$NetBSD: fio.c,v 1.43 2017/11/09 20:27:50 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[] = "@(#)fio.c	8.2 (Berkeley) 4/20/95";
36 #else
37 __RCSID("$NetBSD: fio.c,v 1.43 2017/11/09 20:27:50 christos Exp $");
38 #endif
39 #endif /* not lint */
40 
41 #include "rcv.h"
42 #include "extern.h"
43 #include "thread.h"
44 #include "sig.h"
45 #include <wordexp.h>
46 
47 /*
48  * Mail -- a mail program
49  *
50  * File I/O.
51  */
52 
53 #ifndef THREAD_SUPPORT
54 /************************************************************************/
55 /*
56  * If we have threading support, these routines live in thread.c.
57  */
58 static struct message *message;		/* message structure array */
59 static int msgCount;			/* Count of messages read in */
60 
61 PUBLIC struct message *
62 next_message(struct message *mp)
63 {
64 	if (mp + 1 < message || mp + 1 >= message + msgCount)
65 		return NULL;
66 
67 	return mp + 1;
68 }
69 
70 PUBLIC struct message *
71 prev_message(struct message *mp)
72 {
73 	if (mp - 1 < message || mp - 1 >= message + msgCount)
74 		return NULL;
75 
76 	return mp - 1;
77 }
78 
79 PUBLIC struct message *
80 get_message(int msgnum)
81 {
82 	if (msgnum < 1 || msgnum > msgCount)
83 		return NULL;
84 
85 	return message + msgnum - 1;
86 }
87 
88 PUBLIC int
89 get_msgnum(struct message *mp)
90 {
91 	if (mp < message || mp >= message + msgCount)
92 		return 0;
93 
94 	return mp - message + 1;
95 }
96 
97 PUBLIC int
98 get_msgCount(void)
99 {
100 	return msgCount;
101 }
102 #endif /* THREAD_SUPPORT */
103 /************************************************************************/
104 
105 /*
106  * Initialize a message structure.
107  */
108 static void
109 message_init(struct message *mp, off_t offset, short flags)
110 {
111 	/* use memset so new fields are always zeroed */
112 	(void)memset(mp, 0, sizeof(*mp));
113 	mp->m_flag = flags;
114 	mp->m_block = blockof(offset);
115 	mp->m_offset = blkoffsetof(offset);
116 }
117 
118 /*
119  * Take the data out of the passed ghost file and toss it into
120  * a dynamically allocated message structure.
121  */
122 static void
123 makemessage(FILE *f, int omsgCount, int nmsgCount)
124 {
125 	size_t size;
126 	struct message *omessage;	/* old message structure array */
127 	struct message *nmessage;
128 
129 	omessage = get_abs_message(1);
130 
131 	size = (nmsgCount + 1) * sizeof(*nmessage);
132 	nmessage = realloc(omessage, size);
133 	if (nmessage == NULL)
134 		err(EXIT_FAILURE,
135 		    "Insufficient memory for %d messages", nmsgCount);
136 	if (omsgCount == 0 || omessage == NULL)
137 		dot = nmessage;
138 	else
139 		dot = nmessage + (dot - omessage);
140 
141 	thread_fix_old_links(nmessage, omessage, omsgCount);
142 
143 #ifndef THREAD_SUPPORT
144 	message = nmessage;
145 #endif
146 	size -= (omsgCount + 1) * sizeof(*nmessage);
147 	(void)fflush(f);
148 	(void)lseek(fileno(f), (off_t)sizeof(*nmessage), SEEK_SET);
149 	if (read(fileno(f), &nmessage[omsgCount], size) != (ssize_t)size)
150 		errx(EXIT_FAILURE, "Message temporary file corrupted");
151 
152 	message_init(&nmessage[nmsgCount], (off_t)0, 0); /* append a dummy */
153 
154 	thread_fix_new_links(nmessage, omsgCount, nmsgCount);
155 
156 	(void)Fclose(f);
157 }
158 
159 /*
160  * Append the passed message descriptor onto the temp file.
161  * If the write fails, return 1, else 0
162  */
163 static int
164 append(struct message *mp, FILE *f)
165 {
166 	return fwrite(mp, sizeof(*mp), 1, f) != 1;
167 }
168 
169 /*
170  * Set up the input pointers while copying the mail file into /tmp.
171  */
172 PUBLIC void
173 setptr(FILE *ibuf, off_t offset)
174 {
175 	int c;
176 	size_t len;
177 	char *cp;
178 	const char *cp2;
179 	struct message this;
180 	FILE *mestmp;
181 	int maybe, inhead;
182 	char linebuf[LINESIZE];
183 	int omsgCount;
184 #ifdef THREAD_SUPPORT
185 	int nmsgCount;
186 #else
187 # define nmsgCount	msgCount
188 #endif
189 
190 	/* Get temporary file. */
191 	(void)snprintf(linebuf, LINESIZE, "%s/mail.XXXXXX", tmpdir);
192 	if ((c = mkstemp(linebuf)) == -1 ||
193 	    (mestmp = Fdopen(c, "ref+")) == NULL) {
194 		(void)fprintf(stderr, "mail: can't open %s\n", linebuf);
195 		exit(1);
196 	}
197 	(void)unlink(linebuf);
198 
199 	nmsgCount = get_abs_msgCount();
200 	if (offset == 0) {
201 		nmsgCount = 0;
202 	} else {
203 		/* Seek into the file to get to the new messages */
204 		(void)fseeko(ibuf, offset, 0);
205 		/*
206 		 * We need to make "offset" a pointer to the end of
207 		 * the temp file that has the copy of the mail file.
208 		 * If any messages have been edited, this will be
209 		 * different from the offset into the mail file.
210 		 */
211 		(void)fseek(otf, 0L, SEEK_END);
212 		offset = ftell(otf);
213 	}
214 	omsgCount = nmsgCount;
215 	maybe = 1;
216 	inhead = 0;
217 	message_init(&this, (off_t)0, MUSED|MNEW);
218 
219 	for (;;) {
220 		if (fgets(linebuf, LINESIZE, ibuf) == NULL) {
221 			if (append(&this, mestmp))
222 				err(EXIT_FAILURE, "temporary file");
223 			makemessage(mestmp, omsgCount, nmsgCount);
224 			return;
225 		}
226 		len = strlen(linebuf);
227 		/*
228 		 * Transforms lines ending in <CR><LF> to just <LF>.
229 		 * This allows mail to be able to read Eudora mailboxes
230 		 * that reside on a DOS partition.
231 		 */
232 		if (len >= 2 && linebuf[len - 1] == '\n' &&
233 		    linebuf[len - 2] == '\r') {
234 			linebuf[len - 2] = '\n';
235 			len--;
236 		}
237 		(void)fwrite(linebuf, sizeof(*linebuf), len, otf);
238 		if (ferror(otf))
239 			err(EXIT_FAILURE, "/tmp");
240 		if (len)
241 			linebuf[len - 1] = 0;
242 		if (maybe && linebuf[0] == 'F' && ishead(linebuf)) {
243 			nmsgCount++;
244 			if (append(&this, mestmp))
245 				err(EXIT_FAILURE, "temporary file");
246 			message_init(&this, offset, MUSED|MNEW);
247 			inhead = 1;
248 		} else if (linebuf[0] == 0) {
249 			inhead = 0;
250 		} else if (inhead) {
251 			for (cp = linebuf, cp2 = "status";; cp++) {
252 				if ((c = *cp2++) == 0) {
253 					while (isspace((unsigned char)*cp++))
254 						continue;
255 					if (cp[-1] != ':')
256 						break;
257 					while ((c = *cp++) != '\0')
258 						if (c == 'R')
259 							this.m_flag |= MREAD;
260 						else if (c == 'O')
261 							this.m_flag &= ~MNEW;
262 					inhead = 0;
263 					break;
264 				}
265 				if (*cp != c && *cp != toupper(c))
266 					break;
267 			}
268 		}
269 		offset += len;
270 		this.m_size += len;
271 		this.m_lines++;
272 		if (!inhead) {
273 			int lines_plus_wraps = 1;
274 			int linelen = (int)strlen(linebuf);
275 
276 			if (screenwidth && (int)linelen > screenwidth) {
277 				lines_plus_wraps = linelen / screenwidth;
278 				if (linelen % screenwidth != 0)
279 					++lines_plus_wraps;
280 			}
281 			this.m_blines += lines_plus_wraps;
282 		}
283 		maybe = linebuf[0] == 0;
284 	}
285 }
286 
287 /*
288  * Drop the passed line onto the passed output buffer.
289  * If a write error occurs, return -1, else the count of
290  * characters written, including the newline if requested.
291  */
292 PUBLIC int
293 putline(FILE *obuf, const char *linebuf, int outlf)
294 {
295 	size_t c;
296 
297 	c = strlen(linebuf);
298 	(void)fwrite(linebuf, sizeof(*linebuf), c, obuf);
299 	if (outlf) {
300 		(void)putc('\n', obuf);
301 		c++;
302 	}
303 	if (ferror(obuf))
304 		return -1;
305 	return (int)c;
306 }
307 
308 /*
309  * Read up a line from the specified input into the line
310  * buffer.  Return the number of characters read.  Do not
311  * include the newline at the end.
312  */
313 PUBLIC int
314 readline(FILE *ibuf, char *linebuf, int linesize, int no_restart)
315 {
316 	struct sigaction osa_sigtstp;
317 	struct sigaction osa_sigttin;
318 	struct sigaction osa_sigttou;
319 	int n;
320 
321 	clearerr(ibuf);
322 
323 	sig_check();
324 	if (no_restart) {
325 		(void)sig_setflags(SIGTSTP, 0, &osa_sigtstp);
326 		(void)sig_setflags(SIGTTIN, 0, &osa_sigttin);
327 		(void)sig_setflags(SIGTTOU, 0, &osa_sigttou);
328 	}
329 	if (fgets(linebuf, linesize, ibuf) == NULL)
330 		n = -1;
331 	else {
332 		n = (int)strlen(linebuf);
333 		if (n > 0 && linebuf[n - 1] == '\n')
334 			linebuf[--n] = '\0';
335 	}
336 	if (no_restart) {
337 		(void)sigaction(SIGTSTP, &osa_sigtstp, NULL);
338 		(void)sigaction(SIGTTIN, &osa_sigttin, NULL);
339 		(void)sigaction(SIGTTOU, &osa_sigttou, NULL);
340 	}
341 	sig_check();
342 	return n;
343 }
344 
345 /*
346  * Return a file buffer all ready to read up the
347  * passed message pointer.
348  */
349 PUBLIC FILE *
350 setinput(const struct message *mp)
351 {
352 
353 	(void)fflush(otf);
354 	if (fseek(itf, (long)positionof(mp->m_block, mp->m_offset), SEEK_SET) < 0)
355 		err(EXIT_FAILURE, "fseek");
356 	return itf;
357 }
358 
359 /*
360  * Delete a file, but only if the file is a plain file.
361  */
362 PUBLIC int
363 rm(char *name)
364 {
365 	struct stat sb;
366 
367 	if (stat(name, &sb) < 0)
368 		return -1;
369 	if (!S_ISREG(sb.st_mode)) {
370 		errno = EISDIR;
371 		return -1;
372 	}
373 	return unlink(name);
374 }
375 
376 /*
377  * Determine the size of the file possessed by
378  * the passed buffer.
379  */
380 PUBLIC off_t
381 fsize(FILE *iob)
382 {
383 	struct stat sbuf;
384 
385 	if (fstat(fileno(iob), &sbuf) < 0)
386 		return 0;
387 	return sbuf.st_size;
388 }
389 
390 /*
391  * Determine the current folder directory name.
392  */
393 PUBLIC int
394 getfold(char *name, size_t namesize)
395 {
396 	char unres[PATHSIZE], res[PATHSIZE];
397 	char *folder;
398 
399 	if ((folder = value(ENAME_FOLDER)) == NULL)
400 		return -1;
401 	if (*folder != '/') {
402 		(void)snprintf(unres, sizeof(unres), "%s/%s", homedir, folder);
403 		folder = unres;
404 	}
405 	if (realpath(folder, res) == NULL)
406 		warn("Can't canonicalize folder `%s'", folder);
407 	else
408 		folder = res;
409 	(void)strlcpy(name, folder, namesize);
410 	return 0;
411 }
412 
413 /*
414  * Evaluate the string given as a new mailbox name.
415  * Supported meta characters:
416  *	%	for my system mail box
417  *	%user	for user's system mail box
418  *	#	for previous file
419  *	&	invoker's mbox file
420  *	+file	file in folder directory
421  *	any shell meta character
422  * Return the file name as a dynamic string.
423  */
424 PUBLIC const char *
425 expand(const char *name)
426 {
427 	char xname[PATHSIZE];
428 	char cmdbuf[PATHSIZE];
429 	int e;
430 	wordexp_t we;
431 	sigset_t nset, oset;
432 
433 	/*
434 	 * The order of evaluation is "%" and "#" expand into constants.
435 	 * "&" can expand into "+".  "+" can expand into shell meta characters.
436 	 * Shell meta characters expand into constants.
437 	 * This way, we make no recursive expansion.
438 	 */
439 	switch (*name) {
440 	case '%':
441 		findmail(name[1] ? name + 1 : myname, xname, sizeof(xname));
442 		return savestr(xname);
443 	case '#':
444 		if (name[1] != 0)
445 			break;
446 		if (prevfile[0] == 0) {
447 			warnx("No previous file");
448 			return NULL;
449 		}
450 		return savestr(prevfile);
451 	case '&':
452 		if (name[1] == 0 && (name = value(ENAME_MBOX)) == NULL)
453 			name = "~/mbox";
454 		/* fall through */
455 	}
456 	if (name[0] == '+' && getfold(cmdbuf, sizeof(cmdbuf)) >= 0) {
457 		(void)snprintf(xname, sizeof(xname), "%s/%s", cmdbuf, name + 1);
458 		name = savestr(xname);
459 	}
460 	/* catch the most common shell meta character */
461 	if (name[0] == '~' && (name[1] == '/' || name[1] == '\0')) {
462 		(void)snprintf(xname, sizeof(xname), "%s%s", homedir, name + 1);
463 		name = savestr(xname);
464 	}
465 	if (strpbrk(name, "~{[*?$`'\"\\") == NULL)
466 		return name;
467 
468 	*xname = '\0';
469 
470 	sigemptyset(&nset);
471 	sigaddset(&nset, SIGCHLD);
472 	sigprocmask(SIG_BLOCK, &nset, &oset);
473 	e = wordexp(name, &we, WRDE_NOCMD);
474 	sigprocmask(SIG_SETMASK, &oset, NULL);
475 
476 	switch (e) {
477 	case 0: /* OK */
478 		break;
479 	case WRDE_NOSPACE:
480 		warnx("Out of memory expanding `%s'", name);
481 		return NULL;
482 	case WRDE_BADVAL:
483 	case WRDE_BADCHAR:
484 	case WRDE_SYNTAX:
485 		warnx("Syntax error expanding `%s'", name);
486 		return NULL;
487 	case WRDE_CMDSUB:
488 		warnx("Command substitution not allowed expanding `%s'",
489 		    name);
490 		return NULL;
491 	default:
492 		warnx("Unknown expansion error %d expanding `%s'", e, name);
493 		return NULL;
494 	}
495 
496 	switch (we.we_wordc) {
497 	case 0:
498 		warnx("No match for `%s'", name);
499 		break;
500 	case 1:
501 		if (strlen(we.we_wordv[0]) >= PATHSIZE)
502 			warnx("Expansion too long for `%s'", name);
503 		strlcpy(xname, we.we_wordv[0], PATHSIZE);
504 		break;
505 	default:
506 		warnx("Ambiguous expansion for `%s'", name);
507 		break;
508 	}
509 
510 	wordfree(&we);
511 	if (!*xname)
512 		return NULL;
513 	else
514 		return savestr(xname);
515 }
516 
517 /*
518  * Return the name of the dead.letter file.
519  */
520 PUBLIC const char *
521 getdeadletter(void)
522 {
523 	const char *cp;
524 
525 	if ((cp = value(ENAME_DEAD)) == NULL || (cp = expand(cp)) == NULL)
526 		cp = expand("~/dead.letter");
527 	else if (*cp != '/') {
528 		char buf[PATHSIZE];
529 		(void)snprintf(buf, sizeof(buf), "~/%s", cp);
530 		cp = expand(buf);
531 	}
532 	return cp;
533 }
534