xref: /freebsd/contrib/file/src/file.c (revision dd41de95a84d979615a2ef11df6850622bf6184e)
1 /*
2  * Copyright (c) Ian F. Darwin 1986-1995.
3  * Software written by Ian F. Darwin and others;
4  * maintained 1995-present by Christos Zoulas and others.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice immediately at the beginning of the file, without modification,
11  *    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  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
20  * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 /*
29  * file - find type of a file or files - main program.
30  */
31 
32 #include "file.h"
33 
34 #ifndef	lint
35 FILE_RCSID("@(#)$File: file.c,v 1.187 2020/06/07 17:38:30 christos Exp $")
36 #endif	/* lint */
37 
38 #include "magic.h"
39 
40 #include <stdlib.h>
41 #include <unistd.h>
42 #include <string.h>
43 #ifdef RESTORE_TIME
44 # if (__COHERENT__ >= 0x420)
45 #  include <sys/utime.h>
46 # else
47 #  ifdef USE_UTIMES
48 #   include <sys/time.h>
49 #  else
50 #   include <utime.h>
51 #  endif
52 # endif
53 #endif
54 #ifdef HAVE_UNISTD_H
55 #include <unistd.h>	/* for read() */
56 #endif
57 #ifdef HAVE_WCHAR_H
58 #include <wchar.h>
59 #endif
60 
61 #if defined(HAVE_GETOPT_H) && defined(HAVE_STRUCT_OPTION)
62 # include <getopt.h>
63 # ifndef HAVE_GETOPT_LONG
64 int getopt_long(int, char * const *, const char *,
65     const struct option *, int *);
66 # endif
67 # else
68 #  include "mygetopt.h"
69 #endif
70 
71 #ifdef S_IFLNK
72 # define IFLNK_h "h"
73 # define IFLNK_L "L"
74 #else
75 # define IFLNK_h ""
76 # define IFLNK_L ""
77 #endif
78 
79 #define FILE_FLAGS	"bcCdE" IFLNK_h "ik" IFLNK_L "lNnprsSvzZ0"
80 #define OPTSTRING	"bcCde:Ef:F:hiklLm:nNpP:rsSvzZ0"
81 
82 # define USAGE  \
83     "Usage: %s [-" FILE_FLAGS "] [--apple] [--extension] [--mime-encoding]\n" \
84     "            [--mime-type] [-e <testname>] [-F <separator>] " \
85     " [-f <namefile>]\n" \
86     "            [-m <magicfiles>] [-P <parameter=value>] [--exclude-quiet]\n" \
87     "            <file> ...\n" \
88     "       %s -C [-m <magicfiles>]\n" \
89     "       %s [--help]\n"
90 
91 private int 		/* Global command-line options 		*/
92 	bflag = 0,	/* brief output format	 		*/
93 	nopad = 0,	/* Don't pad output			*/
94 	nobuffer = 0,   /* Do not buffer stdout 		*/
95 	nulsep = 0;	/* Append '\0' to the separator		*/
96 
97 private const char *separator = ":";	/* Default field separator	*/
98 private const struct option long_options[] = {
99 #define OPT_HELP		1
100 #define OPT_APPLE		2
101 #define OPT_EXTENSIONS		3
102 #define OPT_MIME_TYPE		4
103 #define OPT_MIME_ENCODING	5
104 #define OPT_EXCLUDE_QUIET	6
105 #define OPT(shortname, longname, opt, def, doc)		\
106     {longname, opt, NULL, shortname},
107 #define OPT_LONGONLY(longname, opt, def, doc, id)	\
108     {longname, opt, NULL, id},
109 #include "file_opts.h"
110 #undef OPT
111 #undef OPT_LONGONLY
112     {0, 0, NULL, 0}
113     };
114 
115 private const struct {
116 	const char *name;
117 	int value;
118 } nv[] = {
119 	{ "apptype",	MAGIC_NO_CHECK_APPTYPE },
120 	{ "ascii",	MAGIC_NO_CHECK_ASCII },
121 	{ "cdf",	MAGIC_NO_CHECK_CDF },
122 	{ "compress",	MAGIC_NO_CHECK_COMPRESS },
123 	{ "csv",	MAGIC_NO_CHECK_CSV },
124 	{ "elf",	MAGIC_NO_CHECK_ELF },
125 	{ "encoding",	MAGIC_NO_CHECK_ENCODING },
126 	{ "soft",	MAGIC_NO_CHECK_SOFT },
127 	{ "tar",	MAGIC_NO_CHECK_TAR },
128 	{ "json",	MAGIC_NO_CHECK_JSON },
129 	{ "text",	MAGIC_NO_CHECK_TEXT },	/* synonym for ascii */
130 	{ "tokens",	MAGIC_NO_CHECK_TOKENS }, /* OBSOLETE: ignored for backwards compatibility */
131 };
132 
133 private struct {
134 	const char *name;
135 	int tag;
136 	size_t value;
137 	int set;
138 	size_t def;
139 	const char *desc;
140 } pm[] = {
141 	{ "bytes",	MAGIC_PARAM_BYTES_MAX, 0, 0, FILE_BYTES_MAX,
142 	    "max bytes to look inside file" },
143 	{ "elf_notes",	MAGIC_PARAM_ELF_NOTES_MAX, 0, 0, FILE_ELF_NOTES_MAX,
144 	    "max ELF notes processed" },
145 	{ "elf_phnum",	MAGIC_PARAM_ELF_PHNUM_MAX, 0, 0, FILE_ELF_PHNUM_MAX,
146 	    "max ELF prog sections processed" },
147 	{ "elf_shnum",	MAGIC_PARAM_ELF_SHNUM_MAX, 0, 0, FILE_ELF_SHNUM_MAX,
148 	    "max ELF sections processed" },
149 	{ "indir",	MAGIC_PARAM_INDIR_MAX, 0, 0, FILE_INDIR_MAX,
150 	    "recursion limit for indirection" },
151 	{ "name",	MAGIC_PARAM_NAME_MAX, 0, 0, FILE_NAME_MAX,
152 	    "use limit for name/use magic" },
153 	{ "regex",	MAGIC_PARAM_REGEX_MAX, 0, 0, FILE_REGEX_MAX,
154 	    "length limit for REGEX searches" },
155 };
156 
157 private int posixly;
158 
159 #ifdef __dead
160 __dead
161 #endif
162 private void usage(void);
163 private void docprint(const char *, int);
164 #ifdef __dead
165 __dead
166 #endif
167 private void help(void);
168 
169 private int unwrap(struct magic_set *, const char *);
170 private int process(struct magic_set *ms, const char *, int);
171 private struct magic_set *load(const char *, int);
172 private void setparam(const char *);
173 private void applyparam(magic_t);
174 
175 
176 /*
177  * main - parse arguments and handle options
178  */
179 int
180 main(int argc, char *argv[])
181 {
182 	int c;
183 	size_t i;
184 	int action = 0, didsomefiles = 0, errflg = 0;
185 	int flags = 0, e = 0;
186 #ifdef HAVE_LIBSECCOMP
187 	int sandbox = 1;
188 #endif
189 	struct magic_set *magic = NULL;
190 	int longindex;
191 	const char *magicfile = NULL;		/* where the magic is	*/
192 	char *progname;
193 
194 	/* makes islower etc work for other langs */
195 	(void)setlocale(LC_CTYPE, "");
196 
197 #ifdef __EMX__
198 	/* sh-like wildcard expansion! Shouldn't hurt at least ... */
199 	_wildcard(&argc, &argv);
200 #endif
201 
202 	if ((progname = strrchr(argv[0], '/')) != NULL)
203 		progname++;
204 	else
205 		progname = argv[0];
206 
207 	file_setprogname(progname);
208 
209 
210 #ifdef S_IFLNK
211 	posixly = getenv("POSIXLY_CORRECT") != NULL;
212 	flags |=  posixly ? MAGIC_SYMLINK : 0;
213 #endif
214 	while ((c = getopt_long(argc, argv, OPTSTRING, long_options,
215 	    &longindex)) != -1)
216 		switch (c) {
217 		case OPT_HELP:
218 			help();
219 			break;
220 		case OPT_APPLE:
221 			flags |= MAGIC_APPLE;
222 			break;
223 		case OPT_EXTENSIONS:
224 			flags |= MAGIC_EXTENSION;
225 			break;
226 		case OPT_MIME_TYPE:
227 			flags |= MAGIC_MIME_TYPE;
228 			break;
229 		case OPT_MIME_ENCODING:
230 			flags |= MAGIC_MIME_ENCODING;
231 			break;
232 		case '0':
233 			nulsep++;
234 			break;
235 		case 'b':
236 			bflag++;
237 			break;
238 		case 'c':
239 			action = FILE_CHECK;
240 			break;
241 		case 'C':
242 			action = FILE_COMPILE;
243 			break;
244 		case 'd':
245 			flags |= MAGIC_DEBUG|MAGIC_CHECK;
246 			break;
247 		case 'E':
248 			flags |= MAGIC_ERROR;
249 			break;
250 		case 'e':
251 		case OPT_EXCLUDE_QUIET:
252 			for (i = 0; i < __arraycount(nv); i++)
253 				if (strcmp(nv[i].name, optarg) == 0)
254 					break;
255 
256 			if (i == __arraycount(nv)) {
257 				if (c != OPT_EXCLUDE_QUIET)
258 					errflg++;
259 			} else
260 				flags |= nv[i].value;
261 			break;
262 
263 		case 'f':
264 			if(action)
265 				usage();
266 			if (magic == NULL)
267 				if ((magic = load(magicfile, flags)) == NULL)
268 					return 1;
269 			applyparam(magic);
270 			e |= unwrap(magic, optarg);
271 			++didsomefiles;
272 			break;
273 		case 'F':
274 			separator = optarg;
275 			break;
276 		case 'i':
277 			flags |= MAGIC_MIME;
278 			break;
279 		case 'k':
280 			flags |= MAGIC_CONTINUE;
281 			break;
282 		case 'l':
283 			action = FILE_LIST;
284 			break;
285 		case 'm':
286 			magicfile = optarg;
287 			break;
288 		case 'n':
289 			++nobuffer;
290 			break;
291 		case 'N':
292 			++nopad;
293 			break;
294 #if defined(HAVE_UTIME) || defined(HAVE_UTIMES)
295 		case 'p':
296 			flags |= MAGIC_PRESERVE_ATIME;
297 			break;
298 #endif
299 		case 'P':
300 			setparam(optarg);
301 			break;
302 		case 'r':
303 			flags |= MAGIC_RAW;
304 			break;
305 		case 's':
306 			flags |= MAGIC_DEVICES;
307 			break;
308 		case 'S':
309 #ifdef HAVE_LIBSECCOMP
310 			sandbox = 0;
311 #endif
312 			break;
313 		case 'v':
314 			if (magicfile == NULL)
315 				magicfile = magic_getpath(magicfile, action);
316 			(void)fprintf(stdout, "%s-%s\n", file_getprogname(),
317 			    VERSION);
318 			(void)fprintf(stdout, "magic file from %s\n",
319 			    magicfile);
320 #ifdef HAVE_LIBSECCOMP
321 			(void)fprintf(stdout, "seccomp support included\n");
322 #endif
323 			return 0;
324 		case 'z':
325 			flags |= MAGIC_COMPRESS;
326 			break;
327 
328 		case 'Z':
329 			flags |= MAGIC_COMPRESS|MAGIC_COMPRESS_TRANSP;
330 			break;
331 #ifdef S_IFLNK
332 		case 'L':
333 			flags |= MAGIC_SYMLINK;
334 			break;
335 		case 'h':
336 			flags &= ~MAGIC_SYMLINK;
337 			break;
338 #endif
339 		case '?':
340 		default:
341 			errflg++;
342 			break;
343 		}
344 
345 	if (errflg) {
346 		usage();
347 	}
348 	if (e)
349 		return e;
350 
351 #ifdef HAVE_LIBSECCOMP
352 #if 0
353 	if (sandbox && enable_sandbox_basic() == -1)
354 #else
355 	if (sandbox && enable_sandbox_full() == -1)
356 #endif
357 		file_err(EXIT_FAILURE, "SECCOMP initialisation failed");
358 #endif /* HAVE_LIBSECCOMP */
359 
360 	if (MAGIC_VERSION != magic_version())
361 		file_warnx("Compiled magic version [%d] "
362 		    "does not match with shared library magic version [%d]\n",
363 		    MAGIC_VERSION, magic_version());
364 
365 	switch(action) {
366 	case FILE_CHECK:
367 	case FILE_COMPILE:
368 	case FILE_LIST:
369 		/*
370 		 * Don't try to check/compile ~/.magic unless we explicitly
371 		 * ask for it.
372 		 */
373 		magic = magic_open(flags|MAGIC_CHECK);
374 		if (magic == NULL) {
375 			file_warn("Can't create magic");
376 			return 1;
377 		}
378 
379 
380 		switch(action) {
381 		case FILE_CHECK:
382 			c = magic_check(magic, magicfile);
383 			break;
384 		case FILE_COMPILE:
385 			c = magic_compile(magic, magicfile);
386 			break;
387 		case FILE_LIST:
388 			c = magic_list(magic, magicfile);
389 			break;
390 		default:
391 			abort();
392 		}
393 		if (c == -1) {
394 			file_warnx("%s", magic_error(magic));
395 			e = 1;
396 			goto out;
397 		}
398 		goto out;
399 	default:
400 		if (magic == NULL)
401 			if ((magic = load(magicfile, flags)) == NULL)
402 				return 1;
403 		applyparam(magic);
404 	}
405 
406 	if (optind == argc) {
407 		if (!didsomefiles)
408 			usage();
409 	}
410 	else {
411 		size_t j, wid, nw;
412 		for (wid = 0, j = CAST(size_t, optind); j < CAST(size_t, argc);
413 		    j++) {
414 			nw = file_mbswidth(argv[j]);
415 			if (nw > wid)
416 				wid = nw;
417 		}
418 		/*
419 		 * If bflag is only set twice, set it depending on
420 		 * number of files [this is undocumented, and subject to change]
421 		 */
422 		if (bflag == 2) {
423 			bflag = optind >= argc - 1;
424 		}
425 		for (; optind < argc; optind++)
426 			e |= process(magic, argv[optind], wid);
427 	}
428 
429 out:
430 	if (magic)
431 		magic_close(magic);
432 	return e;
433 }
434 
435 private void
436 applyparam(magic_t magic)
437 {
438 	size_t i;
439 
440 	for (i = 0; i < __arraycount(pm); i++) {
441 		if (!pm[i].set)
442 			continue;
443 		if (magic_setparam(magic, pm[i].tag, &pm[i].value) == -1)
444 			file_err(EXIT_FAILURE, "Can't set %s", pm[i].name);
445 	}
446 }
447 
448 private void
449 setparam(const char *p)
450 {
451 	size_t i;
452 	char *s;
453 
454 	if ((s = strchr(p, '=')) == NULL)
455 		goto badparm;
456 
457 	for (i = 0; i < __arraycount(pm); i++) {
458 		if (strncmp(p, pm[i].name, s - p) != 0)
459 			continue;
460 		pm[i].value = atoi(s + 1);
461 		pm[i].set = 1;
462 		return;
463 	}
464 badparm:
465 	file_errx(EXIT_FAILURE, "Unknown param %s", p);
466 }
467 
468 private struct magic_set *
469 /*ARGSUSED*/
470 load(const char *magicfile, int flags)
471 {
472 	struct magic_set *magic = magic_open(flags);
473 	const char *e;
474 
475 	if (magic == NULL) {
476 		file_warn("Can't create magic");
477 		return NULL;
478 	}
479 	if (magic_load(magic, magicfile) == -1) {
480 		file_warn("%s", magic_error(magic));
481 		magic_close(magic);
482 		return NULL;
483 	}
484 	if ((e = magic_error(magic)) != NULL)
485 		file_warn("%s", e);
486 	return magic;
487 }
488 
489 /*
490  * unwrap -- read a file of filenames, do each one.
491  */
492 private int
493 unwrap(struct magic_set *ms, const char *fn)
494 {
495 	FILE *f;
496 	ssize_t len;
497 	char *line = NULL;
498 	size_t llen = 0;
499 	int wid = 0, cwid;
500 	int e = 0;
501 
502 	if (strcmp("-", fn) == 0) {
503 		f = stdin;
504 		wid = 1;
505 	} else {
506 		if ((f = fopen(fn, "r")) == NULL) {
507 			file_warn("Cannot open `%s'", fn);
508 			return 1;
509 		}
510 
511 		while ((len = getline(&line, &llen, f)) > 0) {
512 			if (line[len - 1] == '\n')
513 				line[len - 1] = '\0';
514 			cwid = file_mbswidth(line);
515 			if (cwid > wid)
516 				wid = cwid;
517 		}
518 
519 		rewind(f);
520 	}
521 
522 	while ((len = getline(&line, &llen, f)) > 0) {
523 		if (line[len - 1] == '\n')
524 			line[len - 1] = '\0';
525 		e |= process(ms, line, wid);
526 		if(nobuffer)
527 			(void)fflush(stdout);
528 	}
529 
530 	free(line);
531 	(void)fclose(f);
532 	return e;
533 }
534 
535 /*
536  * Called for each input file on the command line (or in a list of files)
537  */
538 private int
539 process(struct magic_set *ms, const char *inname, int wid)
540 {
541 	const char *type, c = nulsep > 1 ? '\0' : '\n';
542 	int std_in = strcmp(inname, "-") == 0;
543 
544 	if (wid > 0 && !bflag) {
545 		(void)printf("%s", std_in ? "/dev/stdin" : inname);
546 		if (nulsep)
547 			(void)putc('\0', stdout);
548 		if (nulsep < 2) {
549 			(void)printf("%s", separator);
550 			(void)printf("%*s ", CAST(int, nopad ? 0
551 			    : (wid - file_mbswidth(inname))), "");
552 		}
553 	}
554 
555 	type = magic_file(ms, std_in ? NULL : inname);
556 
557 	if (type == NULL) {
558 		(void)printf("ERROR: %s%c", magic_error(ms), c);
559 		return 1;
560 	} else {
561 		(void)printf("%s%c", type, c);
562 		return 0;
563 	}
564 }
565 
566 protected size_t
567 file_mbswidth(const char *s)
568 {
569 #if defined(HAVE_WCHAR_H) && defined(HAVE_MBRTOWC) && defined(HAVE_WCWIDTH)
570 	size_t bytesconsumed, old_n, n, width = 0;
571 	mbstate_t state;
572 	wchar_t nextchar;
573 	(void)memset(&state, 0, sizeof(mbstate_t));
574 	old_n = n = strlen(s);
575 
576 	while (n > 0) {
577 		bytesconsumed = mbrtowc(&nextchar, s, n, &state);
578 		if (bytesconsumed == CAST(size_t, -1) ||
579 		    bytesconsumed == CAST(size_t, -2)) {
580 			/* Something went wrong, return something reasonable */
581 			return old_n;
582 		}
583 		if (s[0] == '\n') {
584 			/*
585 			 * do what strlen() would do, so that caller
586 			 * is always right
587 			 */
588 			width++;
589 		} else {
590 			int w = wcwidth(nextchar);
591 			if (w > 0)
592 				width += w;
593 		}
594 
595 		s += bytesconsumed, n -= bytesconsumed;
596 	}
597 	return width;
598 #else
599 	return strlen(s);
600 #endif
601 }
602 
603 private void
604 usage(void)
605 {
606 	const char *pn = file_getprogname();
607 	(void)fprintf(stderr, USAGE, pn, pn, pn);
608 	exit(EXIT_FAILURE);
609 }
610 
611 private void
612 defprint(int def)
613 {
614 	if (!def)
615 		return;
616 	if (((def & 1) && posixly) || ((def & 2) && !posixly))
617 		fprintf(stdout, " (default)");
618 	fputc('\n', stdout);
619 }
620 
621 private void
622 docprint(const char *opts, int def)
623 {
624 	size_t i;
625 	int comma, pad;
626 	char *sp, *p;
627 
628 	p = strchr(opts, '%');
629 	if (p == NULL) {
630 		fprintf(stdout, "%s", opts);
631 		defprint(def);
632 		return;
633 	}
634 
635 	for (sp = p - 1; sp > opts && *sp == ' '; sp--)
636 		continue;
637 
638 	fprintf(stdout, "%.*s", CAST(int, p - opts), opts);
639 	pad = (int)CAST(int, p - sp - 1);
640 
641 	switch (*++p) {
642 	case 'e':
643 		comma = 0;
644 		for (i = 0; i < __arraycount(nv); i++) {
645 			fprintf(stdout, "%s%s", comma++ ? ", " : "", nv[i].name);
646 			if (i && i % 5 == 0 && i != __arraycount(nv) - 1) {
647 				fprintf(stdout, ",\n%*s", pad, "");
648 				comma = 0;
649 			}
650 		}
651 		break;
652 	case 'P':
653 		for (i = 0; i < __arraycount(pm); i++) {
654 			fprintf(stdout, "%9s %7zu %s", pm[i].name, pm[i].def,
655 			    pm[i].desc);
656 			if (i != __arraycount(pm) - 1)
657 				fprintf(stdout, "\n%*s", pad, "");
658 		}
659 		break;
660 	default:
661 		file_errx(EXIT_FAILURE, "Unknown escape `%c' in long options",
662 		   *p);
663 		break;
664 	}
665 	fprintf(stdout, "%s", opts + (p - opts) + 1);
666 
667 }
668 
669 private void
670 help(void)
671 {
672 	(void)fputs(
673 "Usage: file [OPTION...] [FILE...]\n"
674 "Determine type of FILEs.\n"
675 "\n", stdout);
676 #define OPT(shortname, longname, opt, def, doc)      \
677 	fprintf(stdout, "  -%c, --" longname, shortname), \
678 	docprint(doc, def);
679 #define OPT_LONGONLY(longname, opt, def, doc, id)    	\
680 	fprintf(stdout, "      --" longname),	\
681 	docprint(doc, def);
682 #include "file_opts.h"
683 #undef OPT
684 #undef OPT_LONGONLY
685 	fprintf(stdout, "\nReport bugs to https://bugs.astron.com/\n");
686 	exit(EXIT_SUCCESS);
687 }
688 
689 private const char *file_progname;
690 
691 protected void
692 file_setprogname(const char *progname)
693 {
694 	file_progname = progname;
695 }
696 
697 protected const char *
698 file_getprogname(void)
699 {
700 	return file_progname;
701 }
702 
703 protected void
704 file_err(int e, const char *fmt, ...)
705 {
706 	va_list ap;
707 	int se = errno;
708 
709 	va_start(ap, fmt);
710 	fprintf(stderr, "%s: ", file_progname);
711 	vfprintf(stderr, fmt, ap);
712 	va_end(ap);
713 	if (se)
714 		fprintf(stderr, " (%s)\n", strerror(se));
715 	else
716 		fputc('\n', stderr);
717 	exit(e);
718 }
719 
720 protected void
721 file_errx(int e, const char *fmt, ...)
722 {
723 	va_list ap;
724 
725 	va_start(ap, fmt);
726 	fprintf(stderr, "%s: ", file_progname);
727 	vfprintf(stderr, fmt, ap);
728 	va_end(ap);
729 	fprintf(stderr, "\n");
730 	exit(e);
731 }
732 
733 protected void
734 file_warn(const char *fmt, ...)
735 {
736 	va_list ap;
737 	int se = errno;
738 
739 	va_start(ap, fmt);
740 	fprintf(stderr, "%s: ", file_progname);
741 	vfprintf(stderr, fmt, ap);
742 	va_end(ap);
743 	if (se)
744 		fprintf(stderr, " (%s)\n", strerror(se));
745 	else
746 		fputc('\n', stderr);
747 	errno = se;
748 }
749 
750 protected void
751 file_warnx(const char *fmt, ...)
752 {
753 	va_list ap;
754 	int se = errno;
755 
756 	va_start(ap, fmt);
757 	fprintf(stderr, "%s: ", file_progname);
758 	vfprintf(stderr, fmt, ap);
759 	va_end(ap);
760 	fprintf(stderr, "\n");
761 	errno = se;
762 }
763