xref: /freebsd/usr.bin/fetch/fetch.c (revision 2be1a816b9ff69588e55be0a84cbe2a31efc0f2f)
1 /*-
2  * Copyright (c) 2000-2004 Dag-Erling Co�dan Sm�rgrav
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer
10  *    in this position and unchanged.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  * 3. The name of the author may not be used to endorse or promote products
15  *    derived from this software without specific prior written permission
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27  */
28 
29 #include <sys/cdefs.h>
30 __FBSDID("$FreeBSD$");
31 
32 #include <sys/param.h>
33 #include <sys/socket.h>
34 #include <sys/stat.h>
35 #include <sys/time.h>
36 
37 #include <ctype.h>
38 #include <err.h>
39 #include <errno.h>
40 #include <signal.h>
41 #include <stdint.h>
42 #include <stdio.h>
43 #include <stdlib.h>
44 #include <string.h>
45 #include <sysexits.h>
46 #include <termios.h>
47 #include <unistd.h>
48 
49 #include <fetch.h>
50 
51 #define MINBUFSIZE	4096
52 
53 /* Option flags */
54 int	 A_flag;	/*    -A: do not follow 302 redirects */
55 int	 a_flag;	/*    -a: auto retry */
56 off_t	 B_size;	/*    -B: buffer size */
57 int	 b_flag;	/*!   -b: workaround TCP bug */
58 char    *c_dirname;	/*    -c: remote directory */
59 int	 d_flag;	/*    -d: direct connection */
60 int	 F_flag;	/*    -F: restart without checking mtime  */
61 char	*f_filename;	/*    -f: file to fetch */
62 char	*h_hostname;	/*    -h: host to fetch from */
63 int	 l_flag;	/*    -l: link rather than copy file: URLs */
64 int	 m_flag;	/* -[Mm]: mirror mode */
65 char	*N_filename;	/*    -N: netrc file name */
66 int	 n_flag;	/*    -n: do not preserve modification time */
67 int	 o_flag;	/*    -o: specify output file */
68 int	 o_directory;	/*        output file is a directory */
69 char	*o_filename;	/*        name of output file */
70 int	 o_stdout;	/*        output file is stdout */
71 int	 once_flag;	/*    -1: stop at first successful file */
72 int	 p_flag;	/* -[Pp]: use passive FTP */
73 int	 R_flag;	/*    -R: don't delete partially transferred files */
74 int	 r_flag;	/*    -r: restart previously interrupted transfer */
75 off_t	 S_size;        /*    -S: require size to match */
76 int	 s_flag;        /*    -s: show size, don't fetch */
77 long	 T_secs = 120;	/*    -T: transfer timeout in seconds */
78 int	 t_flag;	/*!   -t: workaround TCP bug */
79 int	 U_flag;	/*    -U: do not use high ports */
80 int	 v_level = 1;	/*    -v: verbosity level */
81 int	 v_tty;		/*        stdout is a tty */
82 pid_t	 pgrp;		/*        our process group */
83 long	 w_secs;	/*    -w: retry delay */
84 int	 family = PF_UNSPEC;	/* -[46]: address family to use */
85 
86 int	 sigalrm;	/* SIGALRM received */
87 int	 siginfo;	/* SIGINFO received */
88 int	 sigint;	/* SIGINT received */
89 
90 long	 ftp_timeout;	/* default timeout for FTP transfers */
91 long	 http_timeout;	/* default timeout for HTTP transfers */
92 char	*buf;		/* transfer buffer */
93 
94 
95 /*
96  * Signal handler
97  */
98 static void
99 sig_handler(int sig)
100 {
101 	switch (sig) {
102 	case SIGALRM:
103 		sigalrm = 1;
104 		break;
105 	case SIGINFO:
106 		siginfo = 1;
107 		break;
108 	case SIGINT:
109 		sigint = 1;
110 		break;
111 	}
112 }
113 
114 struct xferstat {
115 	char		 name[64];
116 	struct timeval	 start;
117 	struct timeval	 last;
118 	off_t		 size;
119 	off_t		 offset;
120 	off_t		 rcvd;
121 };
122 
123 /*
124  * Compute and display ETA
125  */
126 static const char *
127 stat_eta(struct xferstat *xs)
128 {
129 	static char str[16];
130 	long elapsed, eta;
131 	off_t received, expected;
132 
133 	elapsed = xs->last.tv_sec - xs->start.tv_sec;
134 	received = xs->rcvd - xs->offset;
135 	expected = xs->size - xs->rcvd;
136 	eta = (long)((double)elapsed * expected / received);
137 	if (eta > 3600)
138 		snprintf(str, sizeof str, "%02ldh%02ldm",
139 		    eta / 3600, (eta % 3600) / 60);
140 	else
141 		snprintf(str, sizeof str, "%02ldm%02lds",
142 		    eta / 60, eta % 60);
143 	return (str);
144 }
145 
146 /*
147  * Format a number as "xxxx YB" where Y is ' ', 'k', 'M'...
148  */
149 static const char *prefixes = " kMGTP";
150 static const char *
151 stat_bytes(off_t bytes)
152 {
153 	static char str[16];
154 	const char *prefix = prefixes;
155 
156 	while (bytes > 9999 && prefix[1] != '\0') {
157 		bytes /= 1024;
158 		prefix++;
159 	}
160 	snprintf(str, sizeof str, "%4jd %cB", (intmax_t)bytes, *prefix);
161 	return (str);
162 }
163 
164 /*
165  * Compute and display transfer rate
166  */
167 static const char *
168 stat_bps(struct xferstat *xs)
169 {
170 	static char str[16];
171 	double delta, bps;
172 
173 	delta = (xs->last.tv_sec + (xs->last.tv_usec / 1.e6))
174 	    - (xs->start.tv_sec + (xs->start.tv_usec / 1.e6));
175 	if (delta == 0.0) {
176 		snprintf(str, sizeof str, "?? Bps");
177 	} else {
178 		bps = (xs->rcvd - xs->offset) / delta;
179 		snprintf(str, sizeof str, "%sps", stat_bytes((off_t)bps));
180 	}
181 	return (str);
182 }
183 
184 /*
185  * Update the stats display
186  */
187 static void
188 stat_display(struct xferstat *xs, int force)
189 {
190 	struct timeval now;
191 	int ctty_pgrp;
192 
193 	/* check if we're the foreground process */
194 	if (ioctl(STDERR_FILENO, TIOCGPGRP, &ctty_pgrp) == -1 ||
195 	    (pid_t)ctty_pgrp != pgrp)
196 		return;
197 
198 	gettimeofday(&now, NULL);
199 	if (!force && now.tv_sec <= xs->last.tv_sec)
200 		return;
201 	xs->last = now;
202 
203 	fprintf(stderr, "\r%-46.46s", xs->name);
204 	if (xs->size <= 0) {
205 		setproctitle("%s [%s]", xs->name, stat_bytes(xs->rcvd));
206 		fprintf(stderr, "        %s", stat_bytes(xs->rcvd));
207 	} else {
208 		setproctitle("%s [%d%% of %s]", xs->name,
209 		    (int)((100.0 * xs->rcvd) / xs->size),
210 		    stat_bytes(xs->size));
211 		fprintf(stderr, "%3d%% of %s",
212 		    (int)((100.0 * xs->rcvd) / xs->size),
213 		    stat_bytes(xs->size));
214 	}
215 	fprintf(stderr, " %s", stat_bps(xs));
216 	if (xs->size > 0 && xs->rcvd > 0 &&
217 	    xs->last.tv_sec >= xs->start.tv_sec + 10)
218 		fprintf(stderr, " %s", stat_eta(xs));
219 }
220 
221 /*
222  * Initialize the transfer statistics
223  */
224 static void
225 stat_start(struct xferstat *xs, const char *name, off_t size, off_t offset)
226 {
227 	snprintf(xs->name, sizeof xs->name, "%s", name);
228 	gettimeofday(&xs->start, NULL);
229 	xs->last.tv_sec = xs->last.tv_usec = 0;
230 	xs->size = size;
231 	xs->offset = offset;
232 	xs->rcvd = offset;
233 	if (v_tty && v_level > 0)
234 		stat_display(xs, 1);
235 	else if (v_level > 0)
236 		fprintf(stderr, "%-46s", xs->name);
237 }
238 
239 /*
240  * Update the transfer statistics
241  */
242 static void
243 stat_update(struct xferstat *xs, off_t rcvd)
244 {
245 	xs->rcvd = rcvd;
246 	if (v_tty && v_level > 0)
247 		stat_display(xs, 0);
248 }
249 
250 /*
251  * Finalize the transfer statistics
252  */
253 static void
254 stat_end(struct xferstat *xs)
255 {
256 	gettimeofday(&xs->last, NULL);
257 	if (v_tty && v_level > 0) {
258 		stat_display(xs, 1);
259 		putc('\n', stderr);
260 	} else if (v_level > 0) {
261 		fprintf(stderr, "        %s %s\n",
262 		    stat_bytes(xs->size), stat_bps(xs));
263 	}
264 }
265 
266 /*
267  * Ask the user for authentication details
268  */
269 static int
270 query_auth(struct url *URL)
271 {
272 	struct termios tios;
273 	tcflag_t saved_flags;
274 	int i, nopwd;
275 
276 	fprintf(stderr, "Authentication required for <%s://%s:%d/>!\n",
277 	    URL->scheme, URL->host, URL->port);
278 
279 	fprintf(stderr, "Login: ");
280 	if (fgets(URL->user, sizeof URL->user, stdin) == NULL)
281 		return (-1);
282 	for (i = strlen(URL->user); i >= 0; --i)
283 		if (URL->user[i] == '\r' || URL->user[i] == '\n')
284 			URL->user[i] = '\0';
285 
286 	fprintf(stderr, "Password: ");
287 	if (tcgetattr(STDIN_FILENO, &tios) == 0) {
288 		saved_flags = tios.c_lflag;
289 		tios.c_lflag &= ~ECHO;
290 		tios.c_lflag |= ECHONL|ICANON;
291 		tcsetattr(STDIN_FILENO, TCSAFLUSH|TCSASOFT, &tios);
292 		nopwd = (fgets(URL->pwd, sizeof URL->pwd, stdin) == NULL);
293 		tios.c_lflag = saved_flags;
294 		tcsetattr(STDIN_FILENO, TCSANOW|TCSASOFT, &tios);
295 	} else {
296 		nopwd = (fgets(URL->pwd, sizeof URL->pwd, stdin) == NULL);
297 	}
298 	if (nopwd)
299 		return (-1);
300 	for (i = strlen(URL->pwd); i >= 0; --i)
301 		if (URL->pwd[i] == '\r' || URL->pwd[i] == '\n')
302 			URL->pwd[i] = '\0';
303 
304 	return (0);
305 }
306 
307 /*
308  * Fetch a file
309  */
310 static int
311 fetch(char *URL, const char *path)
312 {
313 	struct url *url;
314 	struct url_stat us;
315 	struct stat sb, nsb;
316 	struct xferstat xs;
317 	FILE *f, *of;
318 	size_t size, wr;
319 	off_t count;
320 	char flags[8];
321 	const char *slash;
322 	char *tmppath;
323 	int r;
324 	unsigned timeout;
325 	char *ptr;
326 
327 	f = of = NULL;
328 	tmppath = NULL;
329 
330 	timeout = 0;
331 	*flags = 0;
332 	count = 0;
333 
334 	/* set verbosity level */
335 	if (v_level > 1)
336 		strcat(flags, "v");
337 	if (v_level > 2)
338 		fetchDebug = 1;
339 
340 	/* parse URL */
341 	if ((url = fetchParseURL(URL)) == NULL) {
342 		warnx("%s: parse error", URL);
343 		goto failure;
344 	}
345 
346 	/* if no scheme was specified, take a guess */
347 	if (!*url->scheme) {
348 		if (!*url->host)
349 			strcpy(url->scheme, SCHEME_FILE);
350 		else if (strncasecmp(url->host, "ftp.", 4) == 0)
351 			strcpy(url->scheme, SCHEME_FTP);
352 		else if (strncasecmp(url->host, "www.", 4) == 0)
353 			strcpy(url->scheme, SCHEME_HTTP);
354 	}
355 
356 	/* common flags */
357 	switch (family) {
358 	case PF_INET:
359 		strcat(flags, "4");
360 		break;
361 	case PF_INET6:
362 		strcat(flags, "6");
363 		break;
364 	}
365 
366 	/* FTP specific flags */
367 	if (strcmp(url->scheme, "ftp") == 0) {
368 		if (p_flag)
369 			strcat(flags, "p");
370 		if (d_flag)
371 			strcat(flags, "d");
372 		if (U_flag)
373 			strcat(flags, "l");
374 		timeout = T_secs ? T_secs : ftp_timeout;
375 	}
376 
377 	/* HTTP specific flags */
378 	if (strcmp(url->scheme, "http") == 0) {
379 		if (d_flag)
380 			strcat(flags, "d");
381 		if (A_flag)
382 			strcat(flags, "A");
383 		timeout = T_secs ? T_secs : http_timeout;
384 	}
385 
386 	/* set the protocol timeout. */
387 	fetchTimeout = timeout;
388 
389 	/* just print size */
390 	if (s_flag) {
391 		if (timeout)
392 			alarm(timeout);
393 		r = fetchStat(url, &us, flags);
394 		if (timeout)
395 			alarm(0);
396 		if (sigalrm || sigint)
397 			goto signal;
398 		if (r == -1) {
399 			warnx("%s", fetchLastErrString);
400 			goto failure;
401 		}
402 		if (us.size == -1)
403 			printf("Unknown\n");
404 		else
405 			printf("%jd\n", (intmax_t)us.size);
406 		goto success;
407 	}
408 
409 	/*
410 	 * If the -r flag was specified, we have to compare the local
411 	 * and remote files, so we should really do a fetchStat()
412 	 * first, but I know of at least one HTTP server that only
413 	 * sends the content size in response to GET requests, and
414 	 * leaves it out of replies to HEAD requests.  Also, in the
415 	 * (frequent) case that the local and remote files match but
416 	 * the local file is truncated, we have sufficient information
417 	 * before the compare to issue a correct request.  Therefore,
418 	 * we always issue a GET request as if we were sure the local
419 	 * file was a truncated copy of the remote file; we can drop
420 	 * the connection later if we change our minds.
421 	 */
422 	sb.st_size = -1;
423 	if (!o_stdout) {
424 		r = stat(path, &sb);
425 		if (r == 0 && r_flag && S_ISREG(sb.st_mode)) {
426 			url->offset = sb.st_size;
427 		} else if (r == -1 || !S_ISREG(sb.st_mode)) {
428 			/*
429 			 * Whatever value sb.st_size has now is either
430 			 * wrong (if stat(2) failed) or irrelevant (if the
431 			 * path does not refer to a regular file)
432 			 */
433 			sb.st_size = -1;
434 		}
435 		if (r == -1 && errno != ENOENT) {
436 			warnx("%s: stat()", path);
437 			goto failure;
438 		}
439 	}
440 
441 	/* start the transfer */
442 	if (timeout)
443 		alarm(timeout);
444 	f = fetchXGet(url, &us, flags);
445 	if (timeout)
446 		alarm(0);
447 	if (sigalrm || sigint)
448 		goto signal;
449 	if (f == NULL) {
450 		warnx("%s: %s", URL, fetchLastErrString);
451 		goto failure;
452 	}
453 	if (sigint)
454 		goto signal;
455 
456 	/* check that size is as expected */
457 	if (S_size) {
458 		if (us.size == -1) {
459 			warnx("%s: size unknown", URL);
460 		} else if (us.size != S_size) {
461 			warnx("%s: size mismatch: expected %jd, actual %jd",
462 			    URL, (intmax_t)S_size, (intmax_t)us.size);
463 			goto failure;
464 		}
465 	}
466 
467 	/* symlink instead of copy */
468 	if (l_flag && strcmp(url->scheme, "file") == 0 && !o_stdout) {
469 		if (symlink(url->doc, path) == -1) {
470 			warn("%s: symlink()", path);
471 			goto failure;
472 		}
473 		goto success;
474 	}
475 
476 	if (us.size == -1 && !o_stdout && v_level > 0)
477 		warnx("%s: size of remote file is not known", URL);
478 	if (v_level > 1) {
479 		if (sb.st_size != -1)
480 			fprintf(stderr, "local size / mtime: %jd / %ld\n",
481 			    (intmax_t)sb.st_size, (long)sb.st_mtime);
482 		if (us.size != -1)
483 			fprintf(stderr, "remote size / mtime: %jd / %ld\n",
484 			    (intmax_t)us.size, (long)us.mtime);
485 	}
486 
487 	/* open output file */
488 	if (o_stdout) {
489 		/* output to stdout */
490 		of = stdout;
491 	} else if (r_flag && sb.st_size != -1) {
492 		/* resume mode, local file exists */
493 		if (!F_flag && us.mtime && sb.st_mtime != us.mtime) {
494 			/* no match! have to refetch */
495 			fclose(f);
496 			/* if precious, warn the user and give up */
497 			if (R_flag) {
498 				warnx("%s: local modification time "
499 				    "does not match remote", path);
500 				goto failure_keep;
501 			}
502 		} else if (us.size != -1) {
503 			if (us.size == sb.st_size)
504 				/* nothing to do */
505 				goto success;
506 			if (sb.st_size > us.size) {
507 				/* local file too long! */
508 				warnx("%s: local file (%jd bytes) is longer "
509 				    "than remote file (%jd bytes)", path,
510 				    (intmax_t)sb.st_size, (intmax_t)us.size);
511 				goto failure;
512 			}
513 			/* we got it, open local file */
514 			if ((of = fopen(path, "a")) == NULL) {
515 				warn("%s: fopen()", path);
516 				goto failure;
517 			}
518 			/* check that it didn't move under our feet */
519 			if (fstat(fileno(of), &nsb) == -1) {
520 				/* can't happen! */
521 				warn("%s: fstat()", path);
522 				goto failure;
523 			}
524 			if (nsb.st_dev != sb.st_dev ||
525 			    nsb.st_ino != nsb.st_ino ||
526 			    nsb.st_size != sb.st_size) {
527 				warnx("%s: file has changed", URL);
528 				fclose(of);
529 				of = NULL;
530 				sb = nsb;
531 			}
532 		}
533 	} else if (m_flag && sb.st_size != -1) {
534 		/* mirror mode, local file exists */
535 		if (sb.st_size == us.size && sb.st_mtime == us.mtime)
536 			goto success;
537 	}
538 
539 	if (of == NULL) {
540 		/*
541 		 * We don't yet have an output file; either this is a
542 		 * vanilla run with no special flags, or the local and
543 		 * remote files didn't match.
544 		 */
545 
546 		if (url->offset > 0) {
547 			/*
548 			 * We tried to restart a transfer, but for
549 			 * some reason gave up - so we have to restart
550 			 * from scratch if we want the whole file
551 			 */
552 			url->offset = 0;
553 			if ((f = fetchXGet(url, &us, flags)) == NULL) {
554 				warnx("%s: %s", URL, fetchLastErrString);
555 				goto failure;
556 			}
557 			if (sigint)
558 				goto signal;
559 		}
560 
561 		/* construct a temp file name */
562 		if (sb.st_size != -1 && S_ISREG(sb.st_mode)) {
563 			if ((slash = strrchr(path, '/')) == NULL)
564 				slash = path;
565 			else
566 				++slash;
567 			asprintf(&tmppath, "%.*s.fetch.XXXXXX.%s",
568 			    (int)(slash - path), path, slash);
569 			if (tmppath != NULL) {
570 				mkstemps(tmppath, strlen(slash) + 1);
571 				of = fopen(tmppath, "w");
572 				chown(tmppath, sb.st_uid, sb.st_gid);
573 				chmod(tmppath, sb.st_mode & ALLPERMS);
574 			}
575 		}
576 		if (of == NULL)
577 			of = fopen(path, "w");
578 		if (of == NULL) {
579 			warn("%s: open()", path);
580 			goto failure;
581 		}
582 	}
583 	count = url->offset;
584 
585 	/* start the counter */
586 	stat_start(&xs, path, us.size, count);
587 
588 	sigalrm = siginfo = sigint = 0;
589 
590 	/* suck in the data */
591 	signal(SIGINFO, sig_handler);
592 	while (!sigint) {
593 		if (us.size != -1 && us.size - count < B_size &&
594 		    us.size - count >= 0)
595 			size = us.size - count;
596 		else
597 			size = B_size;
598 		if (siginfo) {
599 			stat_end(&xs);
600 			siginfo = 0;
601 		}
602 		if ((size = fread(buf, 1, size, f)) == 0) {
603 			if (ferror(f) && errno == EINTR && !sigint)
604 				clearerr(f);
605 			else
606 				break;
607 		}
608 		stat_update(&xs, count += size);
609 		for (ptr = buf; size > 0; ptr += wr, size -= wr)
610 			if ((wr = fwrite(ptr, 1, size, of)) < size) {
611 				if (ferror(of) && errno == EINTR && !sigint)
612 					clearerr(of);
613 				else
614 					break;
615 			}
616 		if (size != 0)
617 			break;
618 	}
619 	if (!sigalrm)
620 		sigalrm = ferror(f) && errno == ETIMEDOUT;
621 	signal(SIGINFO, SIG_DFL);
622 
623 	stat_end(&xs);
624 
625 	/*
626 	 * If the transfer timed out or was interrupted, we still want to
627 	 * set the mtime in case the file is not removed (-r or -R) and
628 	 * the user later restarts the transfer.
629 	 */
630  signal:
631 	/* set mtime of local file */
632 	if (!n_flag && us.mtime && !o_stdout && of != NULL &&
633 	    (stat(path, &sb) != -1) && sb.st_mode & S_IFREG) {
634 		struct timeval tv[2];
635 
636 		fflush(of);
637 		tv[0].tv_sec = (long)(us.atime ? us.atime : us.mtime);
638 		tv[1].tv_sec = (long)us.mtime;
639 		tv[0].tv_usec = tv[1].tv_usec = 0;
640 		if (utimes(tmppath ? tmppath : path, tv))
641 			warn("%s: utimes()", tmppath ? tmppath : path);
642 	}
643 
644 	/* timed out or interrupted? */
645 	if (sigalrm)
646 		warnx("transfer timed out");
647 	if (sigint) {
648 		warnx("transfer interrupted");
649 		goto failure;
650 	}
651 
652 	/* timeout / interrupt before connection completley established? */
653 	if (f == NULL)
654 		goto failure;
655 
656 	if (!sigalrm) {
657 		/* check the status of our files */
658 		if (ferror(f))
659 			warn("%s", URL);
660 		if (ferror(of))
661 			warn("%s", path);
662 		if (ferror(f) || ferror(of))
663 			goto failure;
664 	}
665 
666 	/* did the transfer complete normally? */
667 	if (us.size != -1 && count < us.size) {
668 		warnx("%s appears to be truncated: %jd/%jd bytes",
669 		    path, (intmax_t)count, (intmax_t)us.size);
670 		goto failure_keep;
671 	}
672 
673 	/*
674 	 * If the transfer timed out and we didn't know how much to
675 	 * expect, assume the worst (i.e. we didn't get all of it)
676 	 */
677 	if (sigalrm && us.size == -1) {
678 		warnx("%s may be truncated", path);
679 		goto failure_keep;
680 	}
681 
682  success:
683 	r = 0;
684 	if (tmppath != NULL && rename(tmppath, path) == -1) {
685 		warn("%s: rename()", path);
686 		goto failure_keep;
687 	}
688 	goto done;
689  failure:
690 	if (of && of != stdout && !R_flag && !r_flag)
691 		if (stat(path, &sb) != -1 && (sb.st_mode & S_IFREG))
692 			unlink(tmppath ? tmppath : path);
693 	if (R_flag && tmppath != NULL && sb.st_size == -1)
694 		rename(tmppath, path); /* ignore errors here */
695  failure_keep:
696 	r = -1;
697 	goto done;
698  done:
699 	if (f)
700 		fclose(f);
701 	if (of && of != stdout)
702 		fclose(of);
703 	if (url)
704 		fetchFreeURL(url);
705 	if (tmppath != NULL)
706 		free(tmppath);
707 	return (r);
708 }
709 
710 static void
711 usage(void)
712 {
713 	fprintf(stderr, "%s\n%s\n%s\n",
714 	    "usage: fetch [-146AFMPRUadlmnpqrsv] [-N netrc] [-o outputfile]",
715 	    "             [-S bytes] [-B bytes] [-T seconds] [-w seconds]",
716 	    "             [-h host -f file [-c dir] | URL ...]");
717 }
718 
719 
720 /*
721  * Entry point
722  */
723 int
724 main(int argc, char *argv[])
725 {
726 	struct stat sb;
727 	struct sigaction sa;
728 	const char *p, *s;
729 	char *end, *q;
730 	int c, e, r;
731 
732 	while ((c = getopt(argc, argv,
733 	    "146AaB:bc:dFf:Hh:lMmN:nPpo:qRrS:sT:tUvw:")) != -1)
734 		switch (c) {
735 		case '1':
736 			once_flag = 1;
737 			break;
738 		case '4':
739 			family = PF_INET;
740 			break;
741 		case '6':
742 			family = PF_INET6;
743 			break;
744 		case 'A':
745 			A_flag = 1;
746 			break;
747 		case 'a':
748 			a_flag = 1;
749 			break;
750 		case 'B':
751 			B_size = (off_t)strtol(optarg, &end, 10);
752 			if (*optarg == '\0' || *end != '\0')
753 				errx(1, "invalid buffer size (%s)", optarg);
754 			break;
755 		case 'b':
756 			warnx("warning: the -b option is deprecated");
757 			b_flag = 1;
758 			break;
759 		case 'c':
760 			c_dirname = optarg;
761 			break;
762 		case 'd':
763 			d_flag = 1;
764 			break;
765 		case 'F':
766 			F_flag = 1;
767 			break;
768 		case 'f':
769 			f_filename = optarg;
770 			break;
771 		case 'H':
772 			warnx("the -H option is now implicit, "
773 			    "use -U to disable");
774 			break;
775 		case 'h':
776 			h_hostname = optarg;
777 			break;
778 		case 'l':
779 			l_flag = 1;
780 			break;
781 		case 'o':
782 			o_flag = 1;
783 			o_filename = optarg;
784 			break;
785 		case 'M':
786 		case 'm':
787 			if (r_flag)
788 				errx(1, "the -m and -r flags "
789 				    "are mutually exclusive");
790 			m_flag = 1;
791 			break;
792 		case 'N':
793 			N_filename = optarg;
794 			break;
795 		case 'n':
796 			n_flag = 1;
797 			break;
798 		case 'P':
799 		case 'p':
800 			p_flag = 1;
801 			break;
802 		case 'q':
803 			v_level = 0;
804 			break;
805 		case 'R':
806 			R_flag = 1;
807 			break;
808 		case 'r':
809 			if (m_flag)
810 				errx(1, "the -m and -r flags "
811 				    "are mutually exclusive");
812 			r_flag = 1;
813 			break;
814 		case 'S':
815 			S_size = (off_t)strtol(optarg, &end, 10);
816 			if (*optarg == '\0' || *end != '\0')
817 				errx(1, "invalid size (%s)", optarg);
818 			break;
819 		case 's':
820 			s_flag = 1;
821 			break;
822 		case 'T':
823 			T_secs = strtol(optarg, &end, 10);
824 			if (*optarg == '\0' || *end != '\0')
825 				errx(1, "invalid timeout (%s)", optarg);
826 			break;
827 		case 't':
828 			t_flag = 1;
829 			warnx("warning: the -t option is deprecated");
830 			break;
831 		case 'U':
832 			U_flag = 1;
833 			break;
834 		case 'v':
835 			v_level++;
836 			break;
837 		case 'w':
838 			a_flag = 1;
839 			w_secs = strtol(optarg, &end, 10);
840 			if (*optarg == '\0' || *end != '\0')
841 				errx(1, "invalid delay (%s)", optarg);
842 			break;
843 		default:
844 			usage();
845 			exit(EX_USAGE);
846 		}
847 
848 	argc -= optind;
849 	argv += optind;
850 
851 	if (h_hostname || f_filename || c_dirname) {
852 		if (!h_hostname || !f_filename || argc) {
853 			usage();
854 			exit(EX_USAGE);
855 		}
856 		/* XXX this is a hack. */
857 		if (strcspn(h_hostname, "@:/") != strlen(h_hostname))
858 			errx(1, "invalid hostname");
859 		if (asprintf(argv, "ftp://%s/%s/%s", h_hostname,
860 		    c_dirname ? c_dirname : "", f_filename) == -1)
861 			errx(1, "%s", strerror(ENOMEM));
862 		argc++;
863 	}
864 
865 	if (!argc) {
866 		usage();
867 		exit(EX_USAGE);
868 	}
869 
870 	/* allocate buffer */
871 	if (B_size < MINBUFSIZE)
872 		B_size = MINBUFSIZE;
873 	if ((buf = malloc(B_size)) == NULL)
874 		errx(1, "%s", strerror(ENOMEM));
875 
876 	/* timeouts */
877 	if ((s = getenv("FTP_TIMEOUT")) != NULL) {
878 		ftp_timeout = strtol(s, &end, 10);
879 		if (*s == '\0' || *end != '\0' || ftp_timeout < 0) {
880 			warnx("FTP_TIMEOUT (%s) is not a positive integer", s);
881 			ftp_timeout = 0;
882 		}
883 	}
884 	if ((s = getenv("HTTP_TIMEOUT")) != NULL) {
885 		http_timeout = strtol(s, &end, 10);
886 		if (*s == '\0' || *end != '\0' || http_timeout < 0) {
887 			warnx("HTTP_TIMEOUT (%s) is not a positive integer", s);
888 			http_timeout = 0;
889 		}
890 	}
891 
892 	/* signal handling */
893 	sa.sa_flags = 0;
894 	sa.sa_handler = sig_handler;
895 	sigemptyset(&sa.sa_mask);
896 	sigaction(SIGALRM, &sa, NULL);
897 	sa.sa_flags = SA_RESETHAND;
898 	sigaction(SIGINT, &sa, NULL);
899 	fetchRestartCalls = 0;
900 
901 	/* output file */
902 	if (o_flag) {
903 		if (strcmp(o_filename, "-") == 0) {
904 			o_stdout = 1;
905 		} else if (stat(o_filename, &sb) == -1) {
906 			if (errno == ENOENT) {
907 				if (argc > 1)
908 					errx(EX_USAGE, "%s is not a directory",
909 					    o_filename);
910 			} else {
911 				err(EX_IOERR, "%s", o_filename);
912 			}
913 		} else {
914 			if (sb.st_mode & S_IFDIR)
915 				o_directory = 1;
916 		}
917 	}
918 
919 	/* check if output is to a tty (for progress report) */
920 	v_tty = isatty(STDERR_FILENO);
921 	if (v_tty)
922 		pgrp = getpgrp();
923 
924 	r = 0;
925 
926 	/* authentication */
927 	if (v_tty)
928 		fetchAuthMethod = query_auth;
929 	if (N_filename != NULL)
930 		setenv("NETRC", N_filename, 1);
931 
932 	while (argc) {
933 		if ((p = strrchr(*argv, '/')) == NULL)
934 			p = *argv;
935 		else
936 			p++;
937 
938 		if (!*p)
939 			p = "fetch.out";
940 
941 		fetchLastErrCode = 0;
942 
943 		if (o_flag) {
944 			if (o_stdout) {
945 				e = fetch(*argv, "-");
946 			} else if (o_directory) {
947 				asprintf(&q, "%s/%s", o_filename, p);
948 				e = fetch(*argv, q);
949 				free(q);
950 			} else {
951 				e = fetch(*argv, o_filename);
952 			}
953 		} else {
954 			e = fetch(*argv, p);
955 		}
956 
957 		if (sigint)
958 			kill(getpid(), SIGINT);
959 
960 		if (e == 0 && once_flag)
961 			exit(0);
962 
963 		if (e) {
964 			r = 1;
965 			if ((fetchLastErrCode
966 			    && fetchLastErrCode != FETCH_UNAVAIL
967 			    && fetchLastErrCode != FETCH_MOVED
968 			    && fetchLastErrCode != FETCH_URL
969 			    && fetchLastErrCode != FETCH_RESOLV
970 			    && fetchLastErrCode != FETCH_UNKNOWN)) {
971 				if (w_secs && v_level)
972 					fprintf(stderr, "Waiting %ld seconds "
973 					    "before retrying\n", w_secs);
974 				if (w_secs)
975 					sleep(w_secs);
976 				if (a_flag)
977 					continue;
978 			}
979 		}
980 
981 		argc--, argv++;
982 	}
983 
984 	exit(r);
985 }
986