xref: /freebsd/usr.bin/mail/fio.c (revision edf8578117e8844e02c0121147f45e4609b30680)
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 #ifndef lint
33 #if 0
34 static char sccsid[] = "@(#)fio.c	8.2 (Berkeley) 4/20/95";
35 #endif
36 #endif /* not lint */
37 #include <sys/cdefs.h>
38 #include "rcv.h"
39 #include <sys/file.h>
40 #include <sys/wait.h>
41 
42 #include <unistd.h>
43 #include <paths.h>
44 #include <errno.h>
45 #include "extern.h"
46 
47 /*
48  * Mail -- a mail program
49  *
50  * File I/O.
51  */
52 
53 extern int wait_status;
54 
55 /*
56  * Set up the input pointers while copying the mail file into /tmp.
57  */
58 void
59 setptr(FILE *ibuf, off_t offset)
60 {
61 	int c, count;
62 	char *cp, *cp2;
63 	struct message this;
64 	FILE *mestmp;
65 	int maybe, inhead;
66 	char linebuf[LINESIZE], pathbuf[PATHSIZE];
67 	int omsgCount;
68 
69 	/* Get temporary file. */
70 	(void)snprintf(pathbuf, sizeof(pathbuf), "%s/mail.XXXXXXXXXX", tmpdir);
71 	if ((c = mkstemp(pathbuf)) == -1 || (mestmp = Fdopen(c, "r+")) == NULL)
72 		err(1, "can't open %s", pathbuf);
73 	(void)rm(pathbuf);
74 
75 	if (offset == 0) {
76 		 msgCount = 0;
77 	} else {
78 		/* Seek into the file to get to the new messages */
79 		(void)fseeko(ibuf, offset, SEEK_SET);
80 		/*
81 		 * We need to make "offset" a pointer to the end of
82 		 * the temp file that has the copy of the mail file.
83 		 * If any messages have been edited, this will be
84 		 * different from the offset into the mail file.
85 		 */
86 		(void)fseeko(otf, (off_t)0, SEEK_END);
87 		offset = ftello(otf);
88 	}
89 	omsgCount = msgCount;
90 	maybe = 1;
91 	inhead = 0;
92 	this.m_flag = MUSED|MNEW;
93 	this.m_size = 0;
94 	this.m_lines = 0;
95 	this.m_block = 0;
96 	this.m_offset = 0;
97 	for (;;) {
98 		if (fgets(linebuf, sizeof(linebuf), ibuf) == NULL) {
99 			if (append(&this, mestmp))
100 				errx(1, "temporary file");
101 			makemessage(mestmp, omsgCount);
102 			return;
103 		}
104 		count = strlen(linebuf);
105 		/*
106 		 * Transforms lines ending in <CR><LF> to just <LF>.
107 		 * This allows mail to be able to read Eudora mailboxes.
108 		 */
109 		if (count >= 2 && linebuf[count - 1] == '\n' &&
110 		    linebuf[count - 2] == '\r') {
111 			count--;
112 			linebuf[count - 1] = '\n';
113 		}
114 
115 		(void)fwrite(linebuf, sizeof(*linebuf), count, otf);
116 		if (ferror(otf))
117 			errx(1, "/tmp");
118 		if (count)
119 			linebuf[count - 1] = '\0';
120 		if (maybe && linebuf[0] == 'F' && ishead(linebuf)) {
121 			msgCount++;
122 			if (append(&this, mestmp))
123 				errx(1, "temporary file");
124 			this.m_flag = MUSED|MNEW;
125 			this.m_size = 0;
126 			this.m_lines = 0;
127 			this.m_block = blockof(offset);
128 			this.m_offset = boffsetof(offset);
129 			inhead = 1;
130 		} else if (linebuf[0] == 0) {
131 			inhead = 0;
132 		} else if (inhead) {
133 			for (cp = linebuf, cp2 = "status";; cp++) {
134 				if ((c = *cp2++) == '\0') {
135 					while (isspace((unsigned char)*cp++))
136 						;
137 					if (cp[-1] != ':')
138 						break;
139 					while ((c = *cp++) != '\0')
140 						if (c == 'R')
141 							this.m_flag |= MREAD;
142 						else if (c == 'O')
143 							this.m_flag &= ~MNEW;
144 					inhead = 0;
145 					break;
146 				}
147 				if (*cp != c && *cp != toupper((unsigned char)c))
148 					break;
149 			}
150 		}
151 		offset += count;
152 		this.m_size += count;
153 		this.m_lines++;
154 		maybe = linebuf[0] == 0;
155 	}
156 }
157 
158 /*
159  * Drop the passed line onto the passed output buffer.
160  * If a write error occurs, return -1, else the count of
161  * characters written, including the newline if requested.
162  */
163 int
164 putline(FILE *obuf, char *linebuf, int outlf)
165 {
166 	int c;
167 
168 	c = strlen(linebuf);
169 	(void)fwrite(linebuf, sizeof(*linebuf), c, obuf);
170 	if (outlf) {
171 		fprintf(obuf, "\n");
172 		c++;
173 	}
174 	if (ferror(obuf))
175 		return (-1);
176 	return (c);
177 }
178 
179 /*
180  * Read up a line from the specified input into the line
181  * buffer.  Return the number of characters read.  Do not
182  * include the newline (or carriage return) at the end.
183  */
184 int
185 readline(FILE *ibuf, char *linebuf, int linesize)
186 {
187 	int n;
188 
189 	clearerr(ibuf);
190 	if (fgets(linebuf, linesize, ibuf) == NULL)
191 		return (-1);
192 	n = strlen(linebuf);
193 	if (n > 0 && linebuf[n - 1] == '\n')
194 		linebuf[--n] = '\0';
195 	if (n > 0 && linebuf[n - 1] == '\r')
196 		linebuf[--n] = '\0';
197 	return (n);
198 }
199 
200 /*
201  * Return a file buffer all ready to read up the
202  * passed message pointer.
203  */
204 FILE *
205 setinput(struct message *mp)
206 {
207 
208 	(void)fflush(otf);
209 	if (fseeko(itf,
210 		   positionof(mp->m_block, mp->m_offset), SEEK_SET) < 0)
211 		err(1, "fseeko");
212 	return (itf);
213 }
214 
215 /*
216  * Take the data out of the passed ghost file and toss it into
217  * a dynamically allocated message structure.
218  */
219 void
220 makemessage(FILE *f, int omsgCount)
221 {
222 	size_t size;
223 	struct message *nmessage;
224 
225 	size = (msgCount + 1) * sizeof(struct message);
226 	nmessage = (struct message *)realloc(message, size);
227 	if (nmessage == NULL)
228 		errx(1, "Insufficient memory for %d messages\n",
229 		    msgCount);
230 	if (omsgCount == 0 || message == NULL)
231 		dot = nmessage;
232 	else
233 		dot = nmessage + (dot - message);
234 	message = nmessage;
235 	size -= (omsgCount + 1) * sizeof(struct message);
236 	(void)fflush(f);
237 	(void)lseek(fileno(f), (off_t)sizeof(*message), 0);
238 	if (read(fileno(f), (void *)&message[omsgCount], size) != size)
239 		errx(1, "Message temporary file corrupted");
240 	message[msgCount].m_size = 0;
241 	message[msgCount].m_lines = 0;
242 	(void)Fclose(f);
243 }
244 
245 /*
246  * Append the passed message descriptor onto the temp file.
247  * If the write fails, return 1, else 0
248  */
249 int
250 append(struct message *mp, FILE *f)
251 {
252 	return (fwrite((char *)mp, sizeof(*mp), 1, f) != 1);
253 }
254 
255 /*
256  * Delete a file, but only if the file is a plain file.
257  */
258 int
259 rm(char *name)
260 {
261 	struct stat sb;
262 
263 	if (stat(name, &sb) < 0)
264 		return (-1);
265 	if (!S_ISREG(sb.st_mode)) {
266 		errno = EISDIR;
267 		return (-1);
268 	}
269 	return (unlink(name));
270 }
271 
272 static int sigdepth;		/* depth of holdsigs() */
273 static sigset_t nset, oset;
274 /*
275  * Hold signals SIGHUP, SIGINT, and SIGQUIT.
276  */
277 void
278 holdsigs(void)
279 {
280 
281 	if (sigdepth++ == 0) {
282 		(void)sigemptyset(&nset);
283 		(void)sigaddset(&nset, SIGHUP);
284 		(void)sigaddset(&nset, SIGINT);
285 		(void)sigaddset(&nset, SIGQUIT);
286 		(void)sigprocmask(SIG_BLOCK, &nset, &oset);
287 	}
288 }
289 
290 /*
291  * Release signals SIGHUP, SIGINT, and SIGQUIT.
292  */
293 void
294 relsesigs(void)
295 {
296 
297 	if (--sigdepth == 0)
298 		(void)sigprocmask(SIG_SETMASK, &oset, NULL);
299 }
300 
301 /*
302  * Determine the size of the file possessed by
303  * the passed buffer.
304  */
305 off_t
306 fsize(FILE *iob)
307 {
308 	struct stat sbuf;
309 
310 	if (fstat(fileno(iob), &sbuf) < 0)
311 		return (0);
312 	return (sbuf.st_size);
313 }
314 
315 /*
316  * Evaluate the string given as a new mailbox name.
317  * Supported meta characters:
318  *	%	for my system mail box
319  *	%user	for user's system mail box
320  *	#	for previous file
321  *	&	invoker's mbox file
322  *	+file	file in folder directory
323  *	any shell meta character
324  * Return the file name as a dynamic string.
325  */
326 char *
327 expand(char *name)
328 {
329 	char xname[PATHSIZE];
330 	char cmdbuf[PATHSIZE];		/* also used for file names */
331 	int pid, l;
332 	char *cp, *sh;
333 	int pivec[2];
334 	struct stat sbuf;
335 
336 	/*
337 	 * The order of evaluation is "%" and "#" expand into constants.
338 	 * "&" can expand into "+".  "+" can expand into shell meta characters.
339 	 * Shell meta characters expand into constants.
340 	 * This way, we make no recursive expansion.
341 	 */
342 	switch (*name) {
343 	case '%':
344 		findmail(name[1] ? name + 1 : myname, xname, sizeof(xname));
345 		return (savestr(xname));
346 	case '#':
347 		if (name[1] != 0)
348 			break;
349 		if (prevfile[0] == 0) {
350 			printf("No previous file\n");
351 			return (NULL);
352 		}
353 		return (savestr(prevfile));
354 	case '&':
355 		if (name[1] == 0 && (name = value("MBOX")) == NULL)
356 			name = "~/mbox";
357 		/* fall through */
358 	}
359 	if (name[0] == '+' && getfold(cmdbuf, sizeof(cmdbuf)) >= 0) {
360 		(void)snprintf(xname, sizeof(xname), "%s/%s", cmdbuf, name + 1);
361 		name = savestr(xname);
362 	}
363 	/* catch the most common shell meta character */
364 	if (name[0] == '~' && homedir != NULL &&
365 	    (name[1] == '/' || name[1] == '\0')) {
366 		(void)snprintf(xname, sizeof(xname), "%s%s", homedir, name + 1);
367 		name = savestr(xname);
368 	}
369 	if (!strpbrk(name, "~{[*?$`'\"\\"))
370 		return (savestr(name));
371 	if (pipe(pivec) < 0) {
372 		warn("pipe");
373 		return (NULL);
374 	}
375 	(void)snprintf(cmdbuf, sizeof(cmdbuf), "echo %s", name);
376 	if ((sh = value("SHELL")) == NULL)
377 		sh = _PATH_CSHELL;
378 	pid = start_command(sh, 0, -1, pivec[1], "-c", cmdbuf, NULL);
379 	if (pid < 0) {
380 		(void)close(pivec[0]);
381 		(void)close(pivec[1]);
382 		return (NULL);
383 	}
384 	(void)close(pivec[1]);
385 	l = read(pivec[0], xname, BUFSIZ);
386 	(void)close(pivec[0]);
387 	if (wait_child(pid) < 0 && WIFSIGNALED(wait_status) &&
388 	    WTERMSIG(wait_status) != SIGPIPE) {
389 		fprintf(stderr, "\"%s\": Expansion failed.\n", name);
390 		return (NULL);
391 	}
392 	if (l < 0) {
393 		warn("read");
394 		return (NULL);
395 	}
396 	if (l == 0) {
397 		fprintf(stderr, "\"%s\": No match.\n", name);
398 		return (NULL);
399 	}
400 	if (l == BUFSIZ) {
401 		fprintf(stderr, "\"%s\": Expansion buffer overflow.\n", name);
402 		return (NULL);
403 	}
404 	xname[l] = '\0';
405 	for (cp = &xname[l-1]; *cp == '\n' && cp > xname; cp--)
406 		;
407 	cp[1] = '\0';
408 	if (strchr(xname, ' ') && stat(xname, &sbuf) < 0) {
409 		fprintf(stderr, "\"%s\": Ambiguous.\n", name);
410 		return (NULL);
411 	}
412 	return (savestr(xname));
413 }
414 
415 /*
416  * Determine the current folder directory name.
417  */
418 int
419 getfold(char *name, int namelen)
420 {
421 	char *folder;
422 	int copylen;
423 
424 	if ((folder = value("folder")) == NULL)
425 		return (-1);
426 	if (*folder == '/')
427 		copylen = strlcpy(name, folder, namelen);
428 	else
429 		copylen = snprintf(name, namelen, "%s/%s",
430 		    homedir ? homedir : ".", folder);
431 	return (copylen < 0 || copylen >= namelen ? (-1) : (0));
432 }
433 
434 /*
435  * Return the name of the dead.letter file.
436  */
437 char *
438 getdeadletter(void)
439 {
440 	char *cp;
441 
442 	if ((cp = value("DEAD")) == NULL || (cp = expand(cp)) == NULL)
443 		cp = expand("~/dead.letter");
444 	else if (*cp != '/') {
445 		char buf[PATHSIZE];
446 
447 		(void)snprintf(buf, sizeof(buf), "~/%s", cp);
448 		cp = expand(buf);
449 	}
450 	return (cp);
451 }
452