xref: /netbsd-src/usr.bin/mail/fio.c (revision 51157c88ac930fdfc703221b53ba01ee43de29f3)
1 /*	$NetBSD: fio.c,v 1.45 2023/08/23 03:49:00 rin 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 1.45 2023/08/23 03:49:00 rin 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 *
next_message(struct message * mp)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 *
prev_message(struct message * mp)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 *
get_message(int msgnum)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
get_msgnum(struct message * mp)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
get_msgCount(void)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
message_init(struct message * mp,off_t offset,short flags)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
makemessage(FILE * f,int omsgCount,int nmsgCount)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 	ptrdiff_t off;
129 	int need_init;
130 
131 	omessage = get_abs_message(1);
132 
133 	size = (nmsgCount + 1) * sizeof(*nmessage);
134 
135 	if (omsgCount == 0 || omessage == NULL)
136 		off = 0;
137 	else
138 		off = dot - omessage;
139 	need_init = (omessage == NULL);
140 	nmessage = realloc(omessage, size);
141 	if (nmessage == NULL)
142 		err(EXIT_FAILURE,
143 		    "Insufficient memory for %d messages", nmsgCount);
144 	dot = nmessage + off;
145 
146 	if (off != 0 || need_init != 0)
147 		thread_fix_old_links(nmessage, off, omsgCount);
148 
149 #ifndef THREAD_SUPPORT
150 	message = nmessage;
151 #endif
152 	size -= (omsgCount + 1) * sizeof(*nmessage);
153 	(void)fflush(f);
154 	(void)lseek(fileno(f), (off_t)sizeof(*nmessage), SEEK_SET);
155 	if (read(fileno(f), &nmessage[omsgCount], size) != (ssize_t)size)
156 		errx(EXIT_FAILURE, "Message temporary file corrupted");
157 
158 	message_init(&nmessage[nmsgCount], (off_t)0, 0); /* append a dummy */
159 
160 	thread_fix_new_links(nmessage, omsgCount, nmsgCount);
161 
162 	(void)Fclose(f);
163 }
164 
165 /*
166  * Append the passed message descriptor onto the temp file.
167  * If the write fails, return 1, else 0
168  */
169 static int
append(struct message * mp,FILE * f)170 append(struct message *mp, FILE *f)
171 {
172 	return fwrite(mp, sizeof(*mp), 1, f) != 1;
173 }
174 
175 /*
176  * Set up the input pointers while copying the mail file into /tmp.
177  */
178 PUBLIC void
setptr(FILE * ibuf,off_t offset)179 setptr(FILE *ibuf, off_t offset)
180 {
181 	int c;
182 	size_t len;
183 	char *cp;
184 	const char *cp2;
185 	struct message this;
186 	FILE *mestmp;
187 	int maybe, inhead;
188 	char linebuf[LINESIZE];
189 	int omsgCount;
190 #ifdef THREAD_SUPPORT
191 	int nmsgCount;
192 #else
193 # define nmsgCount	msgCount
194 #endif
195 
196 	/* Get temporary file. */
197 	(void)snprintf(linebuf, LINESIZE, "%s/mail.XXXXXX", tmpdir);
198 	if ((c = mkstemp(linebuf)) == -1 ||
199 	    (mestmp = Fdopen(c, "ref+")) == NULL) {
200 		(void)fprintf(stderr, "mail: can't open %s\n", linebuf);
201 		exit(1);
202 	}
203 	(void)unlink(linebuf);
204 
205 	nmsgCount = get_abs_msgCount();
206 	if (offset == 0) {
207 		nmsgCount = 0;
208 	} else {
209 		/* Seek into the file to get to the new messages */
210 		(void)fseeko(ibuf, offset, 0);
211 		/*
212 		 * We need to make "offset" a pointer to the end of
213 		 * the temp file that has the copy of the mail file.
214 		 * If any messages have been edited, this will be
215 		 * different from the offset into the mail file.
216 		 */
217 		(void)fseek(otf, 0L, SEEK_END);
218 		offset = ftell(otf);
219 	}
220 	omsgCount = nmsgCount;
221 	maybe = 1;
222 	inhead = 0;
223 	message_init(&this, (off_t)0, MUSED|MNEW);
224 
225 	for (;;) {
226 		if (fgets(linebuf, LINESIZE, ibuf) == NULL) {
227 			if (append(&this, mestmp))
228 				err(EXIT_FAILURE, "temporary file");
229 			makemessage(mestmp, omsgCount, nmsgCount);
230 			return;
231 		}
232 		len = strlen(linebuf);
233 		/*
234 		 * Transforms lines ending in <CR><LF> to just <LF>.
235 		 * This allows mail to be able to read Eudora mailboxes
236 		 * that reside on a DOS partition.
237 		 */
238 		if (len >= 2 && linebuf[len - 1] == '\n' &&
239 		    linebuf[len - 2] == '\r') {
240 			linebuf[len - 2] = '\n';
241 			len--;
242 		}
243 		(void)fwrite(linebuf, sizeof(*linebuf), len, otf);
244 		if (ferror(otf))
245 			err(EXIT_FAILURE, "/tmp");
246 		if (len)
247 			linebuf[len - 1] = 0;
248 		if (maybe && linebuf[0] == 'F' && ishead(linebuf)) {
249 			nmsgCount++;
250 			if (append(&this, mestmp))
251 				err(EXIT_FAILURE, "temporary file");
252 			message_init(&this, offset, MUSED|MNEW);
253 			inhead = 1;
254 		} else if (linebuf[0] == 0) {
255 			inhead = 0;
256 		} else if (inhead) {
257 			for (cp = linebuf, cp2 = "status";; cp++) {
258 				if ((c = *cp2++) == 0) {
259 					while (isspace((unsigned char)*cp++))
260 						continue;
261 					if (cp[-1] != ':')
262 						break;
263 					while ((c = *cp++) != '\0')
264 						if (c == 'R')
265 							this.m_flag |= MREAD;
266 						else if (c == 'O')
267 							this.m_flag &= ~MNEW;
268 					inhead = 0;
269 					break;
270 				}
271 				if (*cp != c && *cp != toupper(c))
272 					break;
273 			}
274 		}
275 		offset += len;
276 		this.m_size += len;
277 		this.m_lines++;
278 		if (!inhead) {
279 			int lines_plus_wraps = 1;
280 			int linelen = (int)strlen(linebuf);
281 
282 			if (screenwidth && (int)linelen > screenwidth) {
283 				lines_plus_wraps = linelen / screenwidth;
284 				if (linelen % screenwidth != 0)
285 					++lines_plus_wraps;
286 			}
287 			this.m_blines += lines_plus_wraps;
288 		}
289 		maybe = linebuf[0] == 0;
290 	}
291 }
292 
293 /*
294  * Drop the passed line onto the passed output buffer.
295  * If a write error occurs, return -1, else the count of
296  * characters written, including the newline if requested.
297  */
298 PUBLIC int
putline(FILE * obuf,const char * linebuf,int outlf)299 putline(FILE *obuf, const char *linebuf, int outlf)
300 {
301 	size_t c;
302 
303 	c = strlen(linebuf);
304 	(void)fwrite(linebuf, sizeof(*linebuf), c, obuf);
305 	if (outlf) {
306 		(void)putc('\n', obuf);
307 		c++;
308 	}
309 	if (ferror(obuf))
310 		return -1;
311 	return (int)c;
312 }
313 
314 /*
315  * Read up a line from the specified input into the line
316  * buffer.  Return the number of characters read.  Do not
317  * include the newline at the end.
318  */
319 PUBLIC int
readline(FILE * ibuf,char * linebuf,int linesize,int no_restart)320 readline(FILE *ibuf, char *linebuf, int linesize, int no_restart)
321 {
322 	struct sigaction osa_sigtstp;
323 	struct sigaction osa_sigttin;
324 	struct sigaction osa_sigttou;
325 	int n;
326 
327 	clearerr(ibuf);
328 
329 	sig_check();
330 	if (no_restart) {
331 		(void)sig_setflags(SIGTSTP, 0, &osa_sigtstp);
332 		(void)sig_setflags(SIGTTIN, 0, &osa_sigttin);
333 		(void)sig_setflags(SIGTTOU, 0, &osa_sigttou);
334 	}
335 	if (fgets(linebuf, linesize, ibuf) == NULL)
336 		n = -1;
337 	else {
338 		n = (int)strlen(linebuf);
339 		if (n > 0 && linebuf[n - 1] == '\n')
340 			linebuf[--n] = '\0';
341 	}
342 	if (no_restart) {
343 		(void)sigaction(SIGTSTP, &osa_sigtstp, NULL);
344 		(void)sigaction(SIGTTIN, &osa_sigttin, NULL);
345 		(void)sigaction(SIGTTOU, &osa_sigttou, NULL);
346 	}
347 	sig_check();
348 	return n;
349 }
350 
351 /*
352  * Return a file buffer all ready to read up the
353  * passed message pointer.
354  */
355 PUBLIC FILE *
setinput(const struct message * mp)356 setinput(const struct message *mp)
357 {
358 
359 	(void)fflush(otf);
360 	if (fseek(itf, (long)positionof(mp->m_block, mp->m_offset), SEEK_SET) < 0)
361 		err(EXIT_FAILURE, "fseek");
362 	return itf;
363 }
364 
365 /*
366  * Delete a file, but only if the file is a plain file.
367  */
368 PUBLIC int
rm(char * name)369 rm(char *name)
370 {
371 	struct stat sb;
372 
373 	if (stat(name, &sb) < 0)
374 		return -1;
375 	if (!S_ISREG(sb.st_mode)) {
376 		errno = EISDIR;
377 		return -1;
378 	}
379 	return unlink(name);
380 }
381 
382 /*
383  * Determine the size of the file possessed by
384  * the passed buffer.
385  */
386 PUBLIC off_t
fsize(FILE * iob)387 fsize(FILE *iob)
388 {
389 	struct stat sbuf;
390 
391 	if (fstat(fileno(iob), &sbuf) < 0)
392 		return 0;
393 	return sbuf.st_size;
394 }
395 
396 /*
397  * Determine the current folder directory name.
398  */
399 PUBLIC int
getfold(char * name,size_t namesize)400 getfold(char *name, size_t namesize)
401 {
402 	char unres[PATHSIZE], res[PATHSIZE];
403 	char *folder;
404 
405 	if ((folder = value(ENAME_FOLDER)) == NULL)
406 		return -1;
407 	if (*folder != '/') {
408 		(void)snprintf(unres, sizeof(unres), "%s/%s", homedir, folder);
409 		folder = unres;
410 	}
411 	if (realpath(folder, res) == NULL)
412 		warn("Can't canonicalize folder `%s'", folder);
413 	else
414 		folder = res;
415 	(void)strlcpy(name, folder, namesize);
416 	return 0;
417 }
418 
419 /*
420  * Evaluate the string given as a new mailbox name.
421  * Supported meta characters:
422  *	%	for my system mail box
423  *	%user	for user's system mail box
424  *	#	for previous file
425  *	&	invoker's mbox file
426  *	+file	file in folder directory
427  *	any shell meta character
428  * Return the file name as a dynamic string.
429  */
430 PUBLIC const char *
expand(const char * name)431 expand(const char *name)
432 {
433 	char xname[PATHSIZE];
434 	char cmdbuf[PATHSIZE];
435 	int e;
436 	wordexp_t we;
437 	sigset_t nset, oset;
438 
439 	/*
440 	 * The order of evaluation is "%" and "#" expand into constants.
441 	 * "&" can expand into "+".  "+" can expand into shell meta characters.
442 	 * Shell meta characters expand into constants.
443 	 * This way, we make no recursive expansion.
444 	 */
445 	switch (*name) {
446 	case '%':
447 		findmail(name[1] ? name + 1 : myname, xname, sizeof(xname));
448 		return savestr(xname);
449 	case '#':
450 		if (name[1] != 0)
451 			break;
452 		if (prevfile[0] == 0) {
453 			warnx("No previous file");
454 			return NULL;
455 		}
456 		return savestr(prevfile);
457 	case '&':
458 		if (name[1] == 0 && (name = value(ENAME_MBOX)) == NULL)
459 			name = "~/mbox";
460 		/* fall through */
461 	}
462 	if (name[0] == '+' && getfold(cmdbuf, sizeof(cmdbuf)) >= 0) {
463 		(void)snprintf(xname, sizeof(xname), "%s/%s", cmdbuf, name + 1);
464 		name = savestr(xname);
465 	}
466 	/* catch the most common shell meta character */
467 	if (name[0] == '~' && (name[1] == '/' || name[1] == '\0')) {
468 		(void)snprintf(xname, sizeof(xname), "%s%s", homedir, name + 1);
469 		name = savestr(xname);
470 	}
471 	if (strpbrk(name, "~{[*?$`'\"\\") == NULL)
472 		return name;
473 
474 	*xname = '\0';
475 
476 	sigemptyset(&nset);
477 	sigaddset(&nset, SIGCHLD);
478 	sigprocmask(SIG_BLOCK, &nset, &oset);
479 	e = wordexp(name, &we, WRDE_NOCMD);
480 	sigprocmask(SIG_SETMASK, &oset, NULL);
481 
482 	switch (e) {
483 	case 0: /* OK */
484 		break;
485 	case WRDE_NOSPACE:
486 		warnx("Out of memory expanding `%s'", name);
487 		return NULL;
488 	case WRDE_BADVAL:
489 	case WRDE_BADCHAR:
490 	case WRDE_SYNTAX:
491 		warnx("Syntax error expanding `%s'", name);
492 		return NULL;
493 	case WRDE_CMDSUB:
494 		warnx("Command substitution not allowed expanding `%s'",
495 		    name);
496 		return NULL;
497 	default:
498 		warnx("Unknown expansion error %d expanding `%s'", e, name);
499 		return NULL;
500 	}
501 
502 	switch (we.we_wordc) {
503 	case 0:
504 		warnx("No match for `%s'", name);
505 		break;
506 	case 1:
507 		if (strlen(we.we_wordv[0]) >= PATHSIZE)
508 			warnx("Expansion too long for `%s'", name);
509 		strlcpy(xname, we.we_wordv[0], PATHSIZE);
510 		break;
511 	default:
512 		warnx("Ambiguous expansion for `%s'", name);
513 		break;
514 	}
515 
516 	wordfree(&we);
517 	if (!*xname)
518 		return NULL;
519 	else
520 		return savestr(xname);
521 }
522 
523 /*
524  * Return the name of the dead.letter file.
525  */
526 PUBLIC const char *
getdeadletter(void)527 getdeadletter(void)
528 {
529 	const char *cp;
530 
531 	if ((cp = value(ENAME_DEAD)) == NULL || (cp = expand(cp)) == NULL)
532 		cp = expand("~/dead.letter");
533 	else if (*cp != '/') {
534 		char buf[PATHSIZE];
535 		(void)snprintf(buf, sizeof(buf), "~/%s", cp);
536 		cp = expand(buf);
537 	}
538 	return cp;
539 }
540