xref: /freebsd/usr.bin/gzip/gzip.c (revision aa77200569e397d6ff1fdb4d255d0fa254d0a128)
1 /*	$NetBSD: gzip.c,v 1.105 2011/08/30 23:06:00 joerg Exp $	*/
2 
3 /*-
4  * Copyright (c) 1997, 1998, 2003, 2004, 2006 Matthew R. Green
5  * 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  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
21  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
22  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
23  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
24  * 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 
30 #include <sys/cdefs.h>
31 #ifndef lint
32 __COPYRIGHT("@(#) Copyright (c) 1997, 1998, 2003, 2004, 2006\
33  Matthew R. Green.  All rights reserved.");
34 __FBSDID("$FreeBSD$");
35 #endif /* not lint */
36 
37 /*
38  * gzip.c -- GPL free gzip using zlib.
39  *
40  * RFC 1950 covers the zlib format
41  * RFC 1951 covers the deflate format
42  * RFC 1952 covers the gzip format
43  *
44  * TODO:
45  *	- use mmap where possible
46  *	- make bzip2/compress -v/-t/-l support work as well as possible
47  */
48 
49 #include <sys/param.h>
50 #include <sys/stat.h>
51 #include <sys/time.h>
52 
53 #include <inttypes.h>
54 #include <unistd.h>
55 #include <stdio.h>
56 #include <string.h>
57 #include <stdlib.h>
58 #include <err.h>
59 #include <errno.h>
60 #include <fcntl.h>
61 #include <zlib.h>
62 #include <fts.h>
63 #include <libgen.h>
64 #include <stdarg.h>
65 #include <getopt.h>
66 #include <time.h>
67 
68 /* what type of file are we dealing with */
69 enum filetype {
70 	FT_GZIP,
71 #ifndef NO_BZIP2_SUPPORT
72 	FT_BZIP2,
73 #endif
74 #ifndef NO_COMPRESS_SUPPORT
75 	FT_Z,
76 #endif
77 #ifndef NO_PACK_SUPPORT
78 	FT_PACK,
79 #endif
80 #ifndef NO_XZ_SUPPORT
81 	FT_XZ,
82 #endif
83 	FT_LAST,
84 	FT_UNKNOWN
85 };
86 
87 #ifndef NO_BZIP2_SUPPORT
88 #include <bzlib.h>
89 
90 #define BZ2_SUFFIX	".bz2"
91 #define BZIP2_MAGIC	"\102\132\150"
92 #endif
93 
94 #ifndef NO_COMPRESS_SUPPORT
95 #define Z_SUFFIX	".Z"
96 #define Z_MAGIC		"\037\235"
97 #endif
98 
99 #ifndef NO_PACK_SUPPORT
100 #define PACK_MAGIC	"\037\036"
101 #endif
102 
103 #ifndef NO_XZ_SUPPORT
104 #include <lzma.h>
105 #define XZ_SUFFIX	".xz"
106 #define XZ_MAGIC	"\3757zXZ"
107 #endif
108 
109 #define GZ_SUFFIX	".gz"
110 
111 #define BUFLEN		(64 * 1024)
112 
113 #define GZIP_MAGIC0	0x1F
114 #define GZIP_MAGIC1	0x8B
115 #define GZIP_OMAGIC1	0x9E
116 
117 #define GZIP_TIMESTAMP	(off_t)4
118 #define GZIP_ORIGNAME	(off_t)10
119 
120 #define HEAD_CRC	0x02
121 #define EXTRA_FIELD	0x04
122 #define ORIG_NAME	0x08
123 #define COMMENT		0x10
124 
125 #define OS_CODE		3	/* Unix */
126 
127 typedef struct {
128     const char	*zipped;
129     int		ziplen;
130     const char	*normal;	/* for unzip - must not be longer than zipped */
131 } suffixes_t;
132 static suffixes_t suffixes[] = {
133 #define	SUFFIX(Z, N) {Z, sizeof Z - 1, N}
134 	SUFFIX(GZ_SUFFIX,	""),	/* Overwritten by -S .xxx */
135 #ifndef SMALL
136 	SUFFIX(GZ_SUFFIX,	""),
137 	SUFFIX(".z",		""),
138 	SUFFIX("-gz",		""),
139 	SUFFIX("-z",		""),
140 	SUFFIX("_z",		""),
141 	SUFFIX(".taz",		".tar"),
142 	SUFFIX(".tgz",		".tar"),
143 #ifndef NO_BZIP2_SUPPORT
144 	SUFFIX(BZ2_SUFFIX,	""),
145 	SUFFIX(".tbz",		".tar"),
146 	SUFFIX(".tbz2",		".tar"),
147 #endif
148 #ifndef NO_COMPRESS_SUPPORT
149 	SUFFIX(Z_SUFFIX,	""),
150 #endif
151 #ifndef NO_XZ_SUPPORT
152 	SUFFIX(XZ_SUFFIX,	""),
153 #endif
154 	SUFFIX(GZ_SUFFIX,	""),	/* Overwritten by -S "" */
155 #endif /* SMALL */
156 #undef SUFFIX
157 };
158 #define NUM_SUFFIXES (sizeof suffixes / sizeof suffixes[0])
159 #define SUFFIX_MAXLEN	30
160 
161 static	const char	gzip_version[] = "FreeBSD gzip 20111009";
162 
163 #ifndef SMALL
164 static	const char	gzip_copyright[] = \
165 "   Copyright (c) 1997, 1998, 2003, 2004, 2006 Matthew R. Green\n"
166 "   All rights reserved.\n"
167 "\n"
168 "   Redistribution and use in source and binary forms, with or without\n"
169 "   modification, are permitted provided that the following conditions\n"
170 "   are met:\n"
171 "   1. Redistributions of source code must retain the above copyright\n"
172 "      notice, this list of conditions and the following disclaimer.\n"
173 "   2. Redistributions in binary form must reproduce the above copyright\n"
174 "      notice, this list of conditions and the following disclaimer in the\n"
175 "      documentation and/or other materials provided with the distribution.\n"
176 "\n"
177 "   THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR\n"
178 "   IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES\n"
179 "   OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.\n"
180 "   IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,\n"
181 "   INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,\n"
182 "   BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;\n"
183 "   LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED\n"
184 "   AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,\n"
185 "   OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY\n"
186 "   OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF\n"
187 "   SUCH DAMAGE.";
188 #endif
189 
190 static	int	cflag;			/* stdout mode */
191 static	int	dflag;			/* decompress mode */
192 static	int	lflag;			/* list mode */
193 static	int	numflag = 6;		/* gzip -1..-9 value */
194 
195 #ifndef SMALL
196 static	int	fflag;			/* force mode */
197 static	int	kflag;			/* don't delete input files */
198 static	int	nflag;			/* don't save name/timestamp */
199 static	int	Nflag;			/* don't restore name/timestamp */
200 static	int	qflag;			/* quiet mode */
201 static	int	rflag;			/* recursive mode */
202 static	int	tflag;			/* test */
203 static	int	vflag;			/* verbose mode */
204 static	const char *remove_file = NULL;	/* file to be removed upon SIGINT */
205 #else
206 #define		qflag	0
207 #define		tflag	0
208 #endif
209 
210 static	int	exit_value = 0;		/* exit value */
211 
212 static	char	*infile;		/* name of file coming in */
213 
214 static	void	maybe_err(const char *fmt, ...) __printflike(1, 2) __dead2;
215 #if !defined(NO_BZIP2_SUPPORT) || !defined(NO_PACK_SUPPORT) ||	\
216     !defined(NO_XZ_SUPPORT)
217 static	void	maybe_errx(const char *fmt, ...) __printflike(1, 2) __dead2;
218 #endif
219 static	void	maybe_warn(const char *fmt, ...) __printflike(1, 2);
220 static	void	maybe_warnx(const char *fmt, ...) __printflike(1, 2);
221 static	enum filetype file_gettype(u_char *);
222 #ifdef SMALL
223 #define gz_compress(if, of, sz, fn, tm) gz_compress(if, of, sz)
224 #endif
225 static	off_t	gz_compress(int, int, off_t *, const char *, uint32_t);
226 static	off_t	gz_uncompress(int, int, char *, size_t, off_t *, const char *);
227 static	off_t	file_compress(char *, char *, size_t);
228 static	off_t	file_uncompress(char *, char *, size_t);
229 static	void	handle_pathname(char *);
230 static	void	handle_file(char *, struct stat *);
231 static	void	handle_stdin(void);
232 static	void	handle_stdout(void);
233 static	void	print_ratio(off_t, off_t, FILE *);
234 static	void	print_list(int fd, off_t, const char *, time_t);
235 static	void	usage(void) __dead2;
236 static	void	display_version(void) __dead2;
237 #ifndef SMALL
238 static	void	display_license(void);
239 static	void	sigint_handler(int);
240 #endif
241 static	const suffixes_t *check_suffix(char *, int);
242 static	ssize_t	read_retry(int, void *, size_t);
243 
244 #ifdef SMALL
245 #define unlink_input(f, sb) unlink(f)
246 #else
247 static	off_t	cat_fd(unsigned char *, size_t, off_t *, int fd);
248 static	void	prepend_gzip(char *, int *, char ***);
249 static	void	handle_dir(char *);
250 static	void	print_verbage(const char *, const char *, off_t, off_t);
251 static	void	print_test(const char *, int);
252 static	void	copymodes(int fd, const struct stat *, const char *file);
253 static	int	check_outfile(const char *outfile);
254 #endif
255 
256 #ifndef NO_BZIP2_SUPPORT
257 static	off_t	unbzip2(int, int, char *, size_t, off_t *);
258 #endif
259 
260 #ifndef NO_COMPRESS_SUPPORT
261 static	FILE 	*zdopen(int);
262 static	off_t	zuncompress(FILE *, FILE *, char *, size_t, off_t *);
263 #endif
264 
265 #ifndef NO_PACK_SUPPORT
266 static	off_t	unpack(int, int, char *, size_t, off_t *);
267 #endif
268 
269 #ifndef NO_XZ_SUPPORT
270 static	off_t	unxz(int, int, char *, size_t, off_t *);
271 #endif
272 
273 #ifdef SMALL
274 #define getopt_long(a,b,c,d,e) getopt(a,b,c)
275 #else
276 static const struct option longopts[] = {
277 	{ "stdout",		no_argument,		0,	'c' },
278 	{ "to-stdout",		no_argument,		0,	'c' },
279 	{ "decompress",		no_argument,		0,	'd' },
280 	{ "uncompress",		no_argument,		0,	'd' },
281 	{ "force",		no_argument,		0,	'f' },
282 	{ "help",		no_argument,		0,	'h' },
283 	{ "keep",		no_argument,		0,	'k' },
284 	{ "list",		no_argument,		0,	'l' },
285 	{ "no-name",		no_argument,		0,	'n' },
286 	{ "name",		no_argument,		0,	'N' },
287 	{ "quiet",		no_argument,		0,	'q' },
288 	{ "recursive",		no_argument,		0,	'r' },
289 	{ "suffix",		required_argument,	0,	'S' },
290 	{ "test",		no_argument,		0,	't' },
291 	{ "verbose",		no_argument,		0,	'v' },
292 	{ "version",		no_argument,		0,	'V' },
293 	{ "fast",		no_argument,		0,	'1' },
294 	{ "best",		no_argument,		0,	'9' },
295 	{ "ascii",		no_argument,		0,	'a' },
296 	{ "license",		no_argument,		0,	'L' },
297 	{ NULL,			no_argument,		0,	0 },
298 };
299 #endif
300 
301 int
302 main(int argc, char **argv)
303 {
304 	const char *progname = getprogname();
305 #ifndef SMALL
306 	char *gzip;
307 	int len;
308 #endif
309 	int ch;
310 
311 #ifndef SMALL
312 	if ((gzip = getenv("GZIP")) != NULL)
313 		prepend_gzip(gzip, &argc, &argv);
314 	signal(SIGINT, sigint_handler);
315 #endif
316 
317 	/*
318 	 * XXX
319 	 * handle being called `gunzip', `zcat' and `gzcat'
320 	 */
321 	if (strcmp(progname, "gunzip") == 0)
322 		dflag = 1;
323 	else if (strcmp(progname, "zcat") == 0 ||
324 		 strcmp(progname, "gzcat") == 0)
325 		dflag = cflag = 1;
326 
327 #ifdef SMALL
328 #define OPT_LIST "123456789cdhlV"
329 #else
330 #define OPT_LIST "123456789acdfhklLNnqrS:tVv"
331 #endif
332 
333 	while ((ch = getopt_long(argc, argv, OPT_LIST, longopts, NULL)) != -1) {
334 		switch (ch) {
335 		case '1': case '2': case '3':
336 		case '4': case '5': case '6':
337 		case '7': case '8': case '9':
338 			numflag = ch - '0';
339 			break;
340 		case 'c':
341 			cflag = 1;
342 			break;
343 		case 'd':
344 			dflag = 1;
345 			break;
346 		case 'l':
347 			lflag = 1;
348 			dflag = 1;
349 			break;
350 		case 'V':
351 			display_version();
352 			/* NOTREACHED */
353 #ifndef SMALL
354 		case 'a':
355 			fprintf(stderr, "%s: option --ascii ignored on this system\n", progname);
356 			break;
357 		case 'f':
358 			fflag = 1;
359 			break;
360 		case 'k':
361 			kflag = 1;
362 			break;
363 		case 'L':
364 			display_license();
365 			/* NOT REACHED */
366 		case 'N':
367 			nflag = 0;
368 			Nflag = 1;
369 			break;
370 		case 'n':
371 			nflag = 1;
372 			Nflag = 0;
373 			break;
374 		case 'q':
375 			qflag = 1;
376 			break;
377 		case 'r':
378 			rflag = 1;
379 			break;
380 		case 'S':
381 			len = strlen(optarg);
382 			if (len != 0) {
383 				if (len > SUFFIX_MAXLEN)
384 					errx(1, "incorrect suffix: '%s': too long", optarg);
385 				suffixes[0].zipped = optarg;
386 				suffixes[0].ziplen = len;
387 			} else {
388 				suffixes[NUM_SUFFIXES - 1].zipped = "";
389 				suffixes[NUM_SUFFIXES - 1].ziplen = 0;
390 			}
391 			break;
392 		case 't':
393 			cflag = 1;
394 			tflag = 1;
395 			dflag = 1;
396 			break;
397 		case 'v':
398 			vflag = 1;
399 			break;
400 #endif
401 		default:
402 			usage();
403 			/* NOTREACHED */
404 		}
405 	}
406 	argv += optind;
407 	argc -= optind;
408 
409 	if (argc == 0) {
410 		if (dflag)	/* stdin mode */
411 			handle_stdin();
412 		else		/* stdout mode */
413 			handle_stdout();
414 	} else {
415 		do {
416 			handle_pathname(argv[0]);
417 		} while (*++argv);
418 	}
419 #ifndef SMALL
420 	if (qflag == 0 && lflag && argc > 1)
421 		print_list(-1, 0, "(totals)", 0);
422 #endif
423 	exit(exit_value);
424 }
425 
426 /* maybe print a warning */
427 void
428 maybe_warn(const char *fmt, ...)
429 {
430 	va_list ap;
431 
432 	if (qflag == 0) {
433 		va_start(ap, fmt);
434 		vwarn(fmt, ap);
435 		va_end(ap);
436 	}
437 	if (exit_value == 0)
438 		exit_value = 1;
439 }
440 
441 /* ... without an errno. */
442 void
443 maybe_warnx(const char *fmt, ...)
444 {
445 	va_list ap;
446 
447 	if (qflag == 0) {
448 		va_start(ap, fmt);
449 		vwarnx(fmt, ap);
450 		va_end(ap);
451 	}
452 	if (exit_value == 0)
453 		exit_value = 1;
454 }
455 
456 /* maybe print an error */
457 void
458 maybe_err(const char *fmt, ...)
459 {
460 	va_list ap;
461 
462 	if (qflag == 0) {
463 		va_start(ap, fmt);
464 		vwarn(fmt, ap);
465 		va_end(ap);
466 	}
467 	exit(2);
468 }
469 
470 #if !defined(NO_BZIP2_SUPPORT) || !defined(NO_PACK_SUPPORT) ||	\
471     !defined(NO_XZ_SUPPORT)
472 /* ... without an errno. */
473 void
474 maybe_errx(const char *fmt, ...)
475 {
476 	va_list ap;
477 
478 	if (qflag == 0) {
479 		va_start(ap, fmt);
480 		vwarnx(fmt, ap);
481 		va_end(ap);
482 	}
483 	exit(2);
484 }
485 #endif
486 
487 #ifndef SMALL
488 /* split up $GZIP and prepend it to the argument list */
489 static void
490 prepend_gzip(char *gzip, int *argc, char ***argv)
491 {
492 	char *s, **nargv, **ac;
493 	int nenvarg = 0, i;
494 
495 	/* scan how many arguments there are */
496 	for (s = gzip;;) {
497 		while (*s == ' ' || *s == '\t')
498 			s++;
499 		if (*s == 0)
500 			goto count_done;
501 		nenvarg++;
502 		while (*s != ' ' && *s != '\t')
503 			if (*s++ == 0)
504 				goto count_done;
505 	}
506 count_done:
507 	/* punt early */
508 	if (nenvarg == 0)
509 		return;
510 
511 	*argc += nenvarg;
512 	ac = *argv;
513 
514 	nargv = (char **)malloc((*argc + 1) * sizeof(char *));
515 	if (nargv == NULL)
516 		maybe_err("malloc");
517 
518 	/* stash this away */
519 	*argv = nargv;
520 
521 	/* copy the program name first */
522 	i = 0;
523 	nargv[i++] = *(ac++);
524 
525 	/* take a copy of $GZIP and add it to the array */
526 	s = strdup(gzip);
527 	if (s == NULL)
528 		maybe_err("strdup");
529 	for (;;) {
530 		/* Skip whitespaces. */
531 		while (*s == ' ' || *s == '\t')
532 			s++;
533 		if (*s == 0)
534 			goto copy_done;
535 		nargv[i++] = s;
536 		/* Find the end of this argument. */
537 		while (*s != ' ' && *s != '\t')
538 			if (*s++ == 0)
539 				/* Argument followed by NUL. */
540 				goto copy_done;
541 		/* Terminate by overwriting ' ' or '\t' with NUL. */
542 		*s++ = 0;
543 	}
544 copy_done:
545 
546 	/* copy the original arguments and a NULL */
547 	while (*ac)
548 		nargv[i++] = *(ac++);
549 	nargv[i] = NULL;
550 }
551 #endif
552 
553 /* compress input to output. Return bytes read, -1 on error */
554 static off_t
555 gz_compress(int in, int out, off_t *gsizep, const char *origname, uint32_t mtime)
556 {
557 	z_stream z;
558 	char *outbufp, *inbufp;
559 	off_t in_tot = 0, out_tot = 0;
560 	ssize_t in_size;
561 	int i, error;
562 	uLong crc;
563 #ifdef SMALL
564 	static char header[] = { GZIP_MAGIC0, GZIP_MAGIC1, Z_DEFLATED, 0,
565 				 0, 0, 0, 0,
566 				 0, OS_CODE };
567 #endif
568 
569 	outbufp = malloc(BUFLEN);
570 	inbufp = malloc(BUFLEN);
571 	if (outbufp == NULL || inbufp == NULL) {
572 		maybe_err("malloc failed");
573 		goto out;
574 	}
575 
576 	memset(&z, 0, sizeof z);
577 	z.zalloc = Z_NULL;
578 	z.zfree = Z_NULL;
579 	z.opaque = 0;
580 
581 #ifdef SMALL
582 	memcpy(outbufp, header, sizeof header);
583 	i = sizeof header;
584 #else
585 	if (nflag != 0) {
586 		mtime = 0;
587 		origname = "";
588 	}
589 
590 	i = snprintf(outbufp, BUFLEN, "%c%c%c%c%c%c%c%c%c%c%s",
591 		     GZIP_MAGIC0, GZIP_MAGIC1, Z_DEFLATED,
592 		     *origname ? ORIG_NAME : 0,
593 		     mtime & 0xff,
594 		     (mtime >> 8) & 0xff,
595 		     (mtime >> 16) & 0xff,
596 		     (mtime >> 24) & 0xff,
597 		     numflag == 1 ? 4 : numflag == 9 ? 2 : 0,
598 		     OS_CODE, origname);
599 	if (i >= BUFLEN)
600 		/* this need PATH_MAX > BUFLEN ... */
601 		maybe_err("snprintf");
602 	if (*origname)
603 		i++;
604 #endif
605 
606 	z.next_out = (unsigned char *)outbufp + i;
607 	z.avail_out = BUFLEN - i;
608 
609 	error = deflateInit2(&z, numflag, Z_DEFLATED,
610 			     (-MAX_WBITS), 8, Z_DEFAULT_STRATEGY);
611 	if (error != Z_OK) {
612 		maybe_warnx("deflateInit2 failed");
613 		in_tot = -1;
614 		goto out;
615 	}
616 
617 	crc = crc32(0L, Z_NULL, 0);
618 	for (;;) {
619 		if (z.avail_out == 0) {
620 			if (write(out, outbufp, BUFLEN) != BUFLEN) {
621 				maybe_warn("write");
622 				out_tot = -1;
623 				goto out;
624 			}
625 
626 			out_tot += BUFLEN;
627 			z.next_out = (unsigned char *)outbufp;
628 			z.avail_out = BUFLEN;
629 		}
630 
631 		if (z.avail_in == 0) {
632 			in_size = read(in, inbufp, BUFLEN);
633 			if (in_size < 0) {
634 				maybe_warn("read");
635 				in_tot = -1;
636 				goto out;
637 			}
638 			if (in_size == 0)
639 				break;
640 
641 			crc = crc32(crc, (const Bytef *)inbufp, (unsigned)in_size);
642 			in_tot += in_size;
643 			z.next_in = (unsigned char *)inbufp;
644 			z.avail_in = in_size;
645 		}
646 
647 		error = deflate(&z, Z_NO_FLUSH);
648 		if (error != Z_OK && error != Z_STREAM_END) {
649 			maybe_warnx("deflate failed");
650 			in_tot = -1;
651 			goto out;
652 		}
653 	}
654 
655 	/* clean up */
656 	for (;;) {
657 		size_t len;
658 		ssize_t w;
659 
660 		error = deflate(&z, Z_FINISH);
661 		if (error != Z_OK && error != Z_STREAM_END) {
662 			maybe_warnx("deflate failed");
663 			in_tot = -1;
664 			goto out;
665 		}
666 
667 		len = (char *)z.next_out - outbufp;
668 
669 		w = write(out, outbufp, len);
670 		if (w == -1 || (size_t)w != len) {
671 			maybe_warn("write");
672 			out_tot = -1;
673 			goto out;
674 		}
675 		out_tot += len;
676 		z.next_out = (unsigned char *)outbufp;
677 		z.avail_out = BUFLEN;
678 
679 		if (error == Z_STREAM_END)
680 			break;
681 	}
682 
683 	if (deflateEnd(&z) != Z_OK) {
684 		maybe_warnx("deflateEnd failed");
685 		in_tot = -1;
686 		goto out;
687 	}
688 
689 	i = snprintf(outbufp, BUFLEN, "%c%c%c%c%c%c%c%c",
690 		 (int)crc & 0xff,
691 		 (int)(crc >> 8) & 0xff,
692 		 (int)(crc >> 16) & 0xff,
693 		 (int)(crc >> 24) & 0xff,
694 		 (int)in_tot & 0xff,
695 		 (int)(in_tot >> 8) & 0xff,
696 		 (int)(in_tot >> 16) & 0xff,
697 		 (int)(in_tot >> 24) & 0xff);
698 	if (i != 8)
699 		maybe_err("snprintf");
700 	if (write(out, outbufp, i) != i) {
701 		maybe_warn("write");
702 		in_tot = -1;
703 	} else
704 		out_tot += i;
705 
706 out:
707 	if (inbufp != NULL)
708 		free(inbufp);
709 	if (outbufp != NULL)
710 		free(outbufp);
711 	if (gsizep)
712 		*gsizep = out_tot;
713 	return in_tot;
714 }
715 
716 /*
717  * uncompress input to output then close the input.  return the
718  * uncompressed size written, and put the compressed sized read
719  * into `*gsizep'.
720  */
721 static off_t
722 gz_uncompress(int in, int out, char *pre, size_t prelen, off_t *gsizep,
723 	      const char *filename)
724 {
725 	z_stream z;
726 	char *outbufp, *inbufp;
727 	off_t out_tot = -1, in_tot = 0;
728 	uint32_t out_sub_tot = 0;
729 	enum {
730 		GZSTATE_MAGIC0,
731 		GZSTATE_MAGIC1,
732 		GZSTATE_METHOD,
733 		GZSTATE_FLAGS,
734 		GZSTATE_SKIPPING,
735 		GZSTATE_EXTRA,
736 		GZSTATE_EXTRA2,
737 		GZSTATE_EXTRA3,
738 		GZSTATE_ORIGNAME,
739 		GZSTATE_COMMENT,
740 		GZSTATE_HEAD_CRC1,
741 		GZSTATE_HEAD_CRC2,
742 		GZSTATE_INIT,
743 		GZSTATE_READ,
744 		GZSTATE_CRC,
745 		GZSTATE_LEN,
746 	} state = GZSTATE_MAGIC0;
747 	int flags = 0, skip_count = 0;
748 	int error = Z_STREAM_ERROR, done_reading = 0;
749 	uLong crc = 0;
750 	ssize_t wr;
751 	int needmore = 0;
752 
753 #define ADVANCE()       { z.next_in++; z.avail_in--; }
754 
755 	if ((outbufp = malloc(BUFLEN)) == NULL) {
756 		maybe_err("malloc failed");
757 		goto out2;
758 	}
759 	if ((inbufp = malloc(BUFLEN)) == NULL) {
760 		maybe_err("malloc failed");
761 		goto out1;
762 	}
763 
764 	memset(&z, 0, sizeof z);
765 	z.avail_in = prelen;
766 	z.next_in = (unsigned char *)pre;
767 	z.avail_out = BUFLEN;
768 	z.next_out = (unsigned char *)outbufp;
769 	z.zalloc = NULL;
770 	z.zfree = NULL;
771 	z.opaque = 0;
772 
773 	in_tot = prelen;
774 	out_tot = 0;
775 
776 	for (;;) {
777 		if ((z.avail_in == 0 || needmore) && done_reading == 0) {
778 			ssize_t in_size;
779 
780 			if (z.avail_in > 0) {
781 				memmove(inbufp, z.next_in, z.avail_in);
782 			}
783 			z.next_in = (unsigned char *)inbufp;
784 			in_size = read(in, z.next_in + z.avail_in,
785 			    BUFLEN - z.avail_in);
786 
787 			if (in_size == -1) {
788 				maybe_warn("failed to read stdin");
789 				goto stop_and_fail;
790 			} else if (in_size == 0) {
791 				done_reading = 1;
792 			}
793 
794 			z.avail_in += in_size;
795 			needmore = 0;
796 
797 			in_tot += in_size;
798 		}
799 		if (z.avail_in == 0) {
800 			if (done_reading && state != GZSTATE_MAGIC0) {
801 				maybe_warnx("%s: unexpected end of file",
802 					    filename);
803 				goto stop_and_fail;
804 			}
805 			goto stop;
806 		}
807 		switch (state) {
808 		case GZSTATE_MAGIC0:
809 			if (*z.next_in != GZIP_MAGIC0) {
810 				if (in_tot > 0) {
811 					maybe_warnx("%s: trailing garbage "
812 						    "ignored", filename);
813 					goto stop;
814 				}
815 				maybe_warnx("input not gziped (MAGIC0)");
816 				goto stop_and_fail;
817 			}
818 			ADVANCE();
819 			state++;
820 			out_sub_tot = 0;
821 			crc = crc32(0L, Z_NULL, 0);
822 			break;
823 
824 		case GZSTATE_MAGIC1:
825 			if (*z.next_in != GZIP_MAGIC1 &&
826 			    *z.next_in != GZIP_OMAGIC1) {
827 				maybe_warnx("input not gziped (MAGIC1)");
828 				goto stop_and_fail;
829 			}
830 			ADVANCE();
831 			state++;
832 			break;
833 
834 		case GZSTATE_METHOD:
835 			if (*z.next_in != Z_DEFLATED) {
836 				maybe_warnx("unknown compression method");
837 				goto stop_and_fail;
838 			}
839 			ADVANCE();
840 			state++;
841 			break;
842 
843 		case GZSTATE_FLAGS:
844 			flags = *z.next_in;
845 			ADVANCE();
846 			skip_count = 6;
847 			state++;
848 			break;
849 
850 		case GZSTATE_SKIPPING:
851 			if (skip_count > 0) {
852 				skip_count--;
853 				ADVANCE();
854 			} else
855 				state++;
856 			break;
857 
858 		case GZSTATE_EXTRA:
859 			if ((flags & EXTRA_FIELD) == 0) {
860 				state = GZSTATE_ORIGNAME;
861 				break;
862 			}
863 			skip_count = *z.next_in;
864 			ADVANCE();
865 			state++;
866 			break;
867 
868 		case GZSTATE_EXTRA2:
869 			skip_count |= ((*z.next_in) << 8);
870 			ADVANCE();
871 			state++;
872 			break;
873 
874 		case GZSTATE_EXTRA3:
875 			if (skip_count > 0) {
876 				skip_count--;
877 				ADVANCE();
878 			} else
879 				state++;
880 			break;
881 
882 		case GZSTATE_ORIGNAME:
883 			if ((flags & ORIG_NAME) == 0) {
884 				state++;
885 				break;
886 			}
887 			if (*z.next_in == 0)
888 				state++;
889 			ADVANCE();
890 			break;
891 
892 		case GZSTATE_COMMENT:
893 			if ((flags & COMMENT) == 0) {
894 				state++;
895 				break;
896 			}
897 			if (*z.next_in == 0)
898 				state++;
899 			ADVANCE();
900 			break;
901 
902 		case GZSTATE_HEAD_CRC1:
903 			if (flags & HEAD_CRC)
904 				skip_count = 2;
905 			else
906 				skip_count = 0;
907 			state++;
908 			break;
909 
910 		case GZSTATE_HEAD_CRC2:
911 			if (skip_count > 0) {
912 				skip_count--;
913 				ADVANCE();
914 			} else
915 				state++;
916 			break;
917 
918 		case GZSTATE_INIT:
919 			if (inflateInit2(&z, -MAX_WBITS) != Z_OK) {
920 				maybe_warnx("failed to inflateInit");
921 				goto stop_and_fail;
922 			}
923 			state++;
924 			break;
925 
926 		case GZSTATE_READ:
927 			error = inflate(&z, Z_FINISH);
928 			switch (error) {
929 			/* Z_BUF_ERROR goes with Z_FINISH... */
930 			case Z_BUF_ERROR:
931 				if (z.avail_out > 0 && !done_reading)
932 					continue;
933 
934 			case Z_STREAM_END:
935 			case Z_OK:
936 				break;
937 
938 			case Z_NEED_DICT:
939 				maybe_warnx("Z_NEED_DICT error");
940 				goto stop_and_fail;
941 			case Z_DATA_ERROR:
942 				maybe_warnx("data stream error");
943 				goto stop_and_fail;
944 			case Z_STREAM_ERROR:
945 				maybe_warnx("internal stream error");
946 				goto stop_and_fail;
947 			case Z_MEM_ERROR:
948 				maybe_warnx("memory allocation error");
949 				goto stop_and_fail;
950 
951 			default:
952 				maybe_warn("unknown error from inflate(): %d",
953 				    error);
954 			}
955 			wr = BUFLEN - z.avail_out;
956 
957 			if (wr != 0) {
958 				crc = crc32(crc, (const Bytef *)outbufp, (unsigned)wr);
959 				if (
960 #ifndef SMALL
961 				    /* don't write anything with -t */
962 				    tflag == 0 &&
963 #endif
964 				    write(out, outbufp, wr) != wr) {
965 					maybe_warn("error writing to output");
966 					goto stop_and_fail;
967 				}
968 
969 				out_tot += wr;
970 				out_sub_tot += wr;
971 			}
972 
973 			if (error == Z_STREAM_END) {
974 				inflateEnd(&z);
975 				state++;
976 			}
977 
978 			z.next_out = (unsigned char *)outbufp;
979 			z.avail_out = BUFLEN;
980 
981 			break;
982 		case GZSTATE_CRC:
983 			{
984 				uLong origcrc;
985 
986 				if (z.avail_in < 4) {
987 					if (!done_reading) {
988 						needmore = 1;
989 						continue;
990 					}
991 					maybe_warnx("truncated input");
992 					goto stop_and_fail;
993 				}
994 				origcrc = ((unsigned)z.next_in[0] & 0xff) |
995 					((unsigned)z.next_in[1] & 0xff) << 8 |
996 					((unsigned)z.next_in[2] & 0xff) << 16 |
997 					((unsigned)z.next_in[3] & 0xff) << 24;
998 				if (origcrc != crc) {
999 					maybe_warnx("invalid compressed"
1000 					     " data--crc error");
1001 					goto stop_and_fail;
1002 				}
1003 			}
1004 
1005 			z.avail_in -= 4;
1006 			z.next_in += 4;
1007 
1008 			if (!z.avail_in && done_reading) {
1009 				goto stop;
1010 			}
1011 			state++;
1012 			break;
1013 		case GZSTATE_LEN:
1014 			{
1015 				uLong origlen;
1016 
1017 				if (z.avail_in < 4) {
1018 					if (!done_reading) {
1019 						needmore = 1;
1020 						continue;
1021 					}
1022 					maybe_warnx("truncated input");
1023 					goto stop_and_fail;
1024 				}
1025 				origlen = ((unsigned)z.next_in[0] & 0xff) |
1026 					((unsigned)z.next_in[1] & 0xff) << 8 |
1027 					((unsigned)z.next_in[2] & 0xff) << 16 |
1028 					((unsigned)z.next_in[3] & 0xff) << 24;
1029 
1030 				if (origlen != out_sub_tot) {
1031 					maybe_warnx("invalid compressed"
1032 					     " data--length error");
1033 					goto stop_and_fail;
1034 				}
1035 			}
1036 
1037 			z.avail_in -= 4;
1038 			z.next_in += 4;
1039 
1040 			if (error < 0) {
1041 				maybe_warnx("decompression error");
1042 				goto stop_and_fail;
1043 			}
1044 			state = GZSTATE_MAGIC0;
1045 			break;
1046 		}
1047 		continue;
1048 stop_and_fail:
1049 		out_tot = -1;
1050 stop:
1051 		break;
1052 	}
1053 	if (state > GZSTATE_INIT)
1054 		inflateEnd(&z);
1055 
1056 	free(inbufp);
1057 out1:
1058 	free(outbufp);
1059 out2:
1060 	if (gsizep)
1061 		*gsizep = in_tot;
1062 	return (out_tot);
1063 }
1064 
1065 #ifndef SMALL
1066 /*
1067  * set the owner, mode, flags & utimes using the given file descriptor.
1068  * file is only used in possible warning messages.
1069  */
1070 static void
1071 copymodes(int fd, const struct stat *sbp, const char *file)
1072 {
1073 	struct timeval times[2];
1074 	struct stat sb;
1075 
1076 	/*
1077 	 * If we have no info on the input, give this file some
1078 	 * default values and return..
1079 	 */
1080 	if (sbp == NULL) {
1081 		mode_t mask = umask(022);
1082 
1083 		(void)fchmod(fd, DEFFILEMODE & ~mask);
1084 		(void)umask(mask);
1085 		return;
1086 	}
1087 	sb = *sbp;
1088 
1089 	/* if the chown fails, remove set-id bits as-per compress(1) */
1090 	if (fchown(fd, sb.st_uid, sb.st_gid) < 0) {
1091 		if (errno != EPERM)
1092 			maybe_warn("couldn't fchown: %s", file);
1093 		sb.st_mode &= ~(S_ISUID|S_ISGID);
1094 	}
1095 
1096 	/* we only allow set-id and the 9 normal permission bits */
1097 	sb.st_mode &= S_ISUID | S_ISGID | S_IRWXU | S_IRWXG | S_IRWXO;
1098 	if (fchmod(fd, sb.st_mode) < 0)
1099 		maybe_warn("couldn't fchmod: %s", file);
1100 
1101 	TIMESPEC_TO_TIMEVAL(&times[0], &sb.st_atim);
1102 	TIMESPEC_TO_TIMEVAL(&times[1], &sb.st_mtim);
1103 	if (futimes(fd, times) < 0)
1104 		maybe_warn("couldn't utimes: %s", file);
1105 
1106 	/* only try flags if they exist already */
1107         if (sb.st_flags != 0 && fchflags(fd, sb.st_flags) < 0)
1108 		maybe_warn("couldn't fchflags: %s", file);
1109 }
1110 #endif
1111 
1112 /* what sort of file is this? */
1113 static enum filetype
1114 file_gettype(u_char *buf)
1115 {
1116 
1117 	if (buf[0] == GZIP_MAGIC0 &&
1118 	    (buf[1] == GZIP_MAGIC1 || buf[1] == GZIP_OMAGIC1))
1119 		return FT_GZIP;
1120 	else
1121 #ifndef NO_BZIP2_SUPPORT
1122 	if (memcmp(buf, BZIP2_MAGIC, 3) == 0 &&
1123 	    buf[3] >= '0' && buf[3] <= '9')
1124 		return FT_BZIP2;
1125 	else
1126 #endif
1127 #ifndef NO_COMPRESS_SUPPORT
1128 	if (memcmp(buf, Z_MAGIC, 2) == 0)
1129 		return FT_Z;
1130 	else
1131 #endif
1132 #ifndef NO_PACK_SUPPORT
1133 	if (memcmp(buf, PACK_MAGIC, 2) == 0)
1134 		return FT_PACK;
1135 	else
1136 #endif
1137 #ifndef NO_XZ_SUPPORT
1138 	if (memcmp(buf, XZ_MAGIC, 4) == 0)	/* XXX: We only have 4 bytes */
1139 		return FT_XZ;
1140 	else
1141 #endif
1142 		return FT_UNKNOWN;
1143 }
1144 
1145 #ifndef SMALL
1146 /* check the outfile is OK. */
1147 static int
1148 check_outfile(const char *outfile)
1149 {
1150 	struct stat sb;
1151 	int ok = 1;
1152 
1153 	if (lflag == 0 && stat(outfile, &sb) == 0) {
1154 		if (fflag)
1155 			unlink(outfile);
1156 		else if (isatty(STDIN_FILENO)) {
1157 			char ans[10] = { 'n', '\0' };	/* default */
1158 
1159 			fprintf(stderr, "%s already exists -- do you wish to "
1160 					"overwrite (y or n)? " , outfile);
1161 			(void)fgets(ans, sizeof(ans) - 1, stdin);
1162 			if (ans[0] != 'y' && ans[0] != 'Y') {
1163 				fprintf(stderr, "\tnot overwriting\n");
1164 				ok = 0;
1165 			} else
1166 				unlink(outfile);
1167 		} else {
1168 			maybe_warnx("%s already exists -- skipping", outfile);
1169 			ok = 0;
1170 		}
1171 	}
1172 	return ok;
1173 }
1174 
1175 static void
1176 unlink_input(const char *file, const struct stat *sb)
1177 {
1178 	struct stat nsb;
1179 
1180 	if (kflag)
1181 		return;
1182 	if (stat(file, &nsb) != 0)
1183 		/* Must be gone already */
1184 		return;
1185 	if (nsb.st_dev != sb->st_dev || nsb.st_ino != sb->st_ino)
1186 		/* Definitely a different file */
1187 		return;
1188 	unlink(file);
1189 }
1190 
1191 static void
1192 sigint_handler(int signo __unused)
1193 {
1194 
1195 	if (remove_file != NULL)
1196 		unlink(remove_file);
1197 	_exit(2);
1198 }
1199 #endif
1200 
1201 static const suffixes_t *
1202 check_suffix(char *file, int xlate)
1203 {
1204 	const suffixes_t *s;
1205 	int len = strlen(file);
1206 	char *sp;
1207 
1208 	for (s = suffixes; s != suffixes + NUM_SUFFIXES; s++) {
1209 		/* if it doesn't fit in "a.suf", don't bother */
1210 		if (s->ziplen >= len)
1211 			continue;
1212 		sp = file + len - s->ziplen;
1213 		if (strcmp(s->zipped, sp) != 0)
1214 			continue;
1215 		if (xlate)
1216 			strcpy(sp, s->normal);
1217 		return s;
1218 	}
1219 	return NULL;
1220 }
1221 
1222 /*
1223  * compress the given file: create a corresponding .gz file and remove the
1224  * original.
1225  */
1226 static off_t
1227 file_compress(char *file, char *outfile, size_t outsize)
1228 {
1229 	int in;
1230 	int out;
1231 	off_t size, insize;
1232 #ifndef SMALL
1233 	struct stat isb, osb;
1234 	const suffixes_t *suff;
1235 #endif
1236 
1237 	in = open(file, O_RDONLY);
1238 	if (in == -1) {
1239 		maybe_warn("can't open %s", file);
1240 		return (-1);
1241 	}
1242 
1243 #ifndef SMALL
1244 	if (fstat(in, &isb) != 0) {
1245 		maybe_warn("couldn't stat: %s", file);
1246 		close(in);
1247 		return (-1);
1248 	}
1249 #endif
1250 
1251 	if (cflag == 0) {
1252 #ifndef SMALL
1253 		if (isb.st_nlink > 1 && fflag == 0) {
1254 			maybe_warnx("%s has %d other link%s -- skipping",
1255 			    file, isb.st_nlink - 1,
1256 			    (isb.st_nlink - 1) == 1 ? "" : "s");
1257 			close(in);
1258 			return (-1);
1259 		}
1260 
1261 		if (fflag == 0 && (suff = check_suffix(file, 0)) &&
1262 		    suff->zipped[0] != 0) {
1263 			maybe_warnx("%s already has %s suffix -- unchanged",
1264 			    file, suff->zipped);
1265 			close(in);
1266 			return (-1);
1267 		}
1268 #endif
1269 
1270 		/* Add (usually) .gz to filename */
1271 		if ((size_t)snprintf(outfile, outsize, "%s%s",
1272 		    file, suffixes[0].zipped) >= outsize)
1273 			memcpy(outfile + outsize - suffixes[0].ziplen - 1,
1274 			    suffixes[0].zipped, suffixes[0].ziplen + 1);
1275 
1276 #ifndef SMALL
1277 		if (check_outfile(outfile) == 0) {
1278 			close(in);
1279 			return (-1);
1280 		}
1281 #endif
1282 	}
1283 
1284 	if (cflag == 0) {
1285 		out = open(outfile, O_WRONLY | O_CREAT | O_EXCL, 0600);
1286 		if (out == -1) {
1287 			maybe_warn("could not create output: %s", outfile);
1288 			fclose(stdin);
1289 			return (-1);
1290 		}
1291 #ifndef SMALL
1292 		remove_file = outfile;
1293 #endif
1294 	} else
1295 		out = STDOUT_FILENO;
1296 
1297 	insize = gz_compress(in, out, &size, basename(file), (uint32_t)isb.st_mtime);
1298 
1299 	(void)close(in);
1300 
1301 	/*
1302 	 * If there was an error, insize will be -1.
1303 	 * If we compressed to stdout, just return the size.
1304 	 * Otherwise stat the file and check it is the correct size.
1305 	 * We only blow away the file if we can stat the output and it
1306 	 * has the expected size.
1307 	 */
1308 	if (cflag != 0)
1309 		return (insize == -1 ? -1 : size);
1310 
1311 #ifndef SMALL
1312 	if (fstat(out, &osb) != 0) {
1313 		maybe_warn("couldn't stat: %s", outfile);
1314 		goto bad_outfile;
1315 	}
1316 
1317 	if (osb.st_size != size) {
1318 		maybe_warnx("output file: %s wrong size (%ju != %ju), deleting",
1319 		    outfile, (uintmax_t)osb.st_size, (uintmax_t)size);
1320 		goto bad_outfile;
1321 	}
1322 
1323 	copymodes(out, &isb, outfile);
1324 	remove_file = NULL;
1325 #endif
1326 	if (close(out) == -1)
1327 		maybe_warn("couldn't close output");
1328 
1329 	/* output is good, ok to delete input */
1330 	unlink_input(file, &isb);
1331 	return (size);
1332 
1333 #ifndef SMALL
1334     bad_outfile:
1335 	if (close(out) == -1)
1336 		maybe_warn("couldn't close output");
1337 
1338 	maybe_warnx("leaving original %s", file);
1339 	unlink(outfile);
1340 	return (size);
1341 #endif
1342 }
1343 
1344 /* uncompress the given file and remove the original */
1345 static off_t
1346 file_uncompress(char *file, char *outfile, size_t outsize)
1347 {
1348 	struct stat isb, osb;
1349 	off_t size;
1350 	ssize_t rbytes;
1351 	unsigned char header1[4];
1352 	enum filetype method;
1353 	int fd, ofd, zfd = -1;
1354 #ifndef SMALL
1355 	ssize_t rv;
1356 	time_t timestamp = 0;
1357 	unsigned char name[PATH_MAX + 1];
1358 #endif
1359 
1360 	/* gather the old name info */
1361 
1362 	fd = open(file, O_RDONLY);
1363 	if (fd < 0) {
1364 		maybe_warn("can't open %s", file);
1365 		goto lose;
1366 	}
1367 
1368 	strlcpy(outfile, file, outsize);
1369 	if (check_suffix(outfile, 1) == NULL && !(cflag || lflag)) {
1370 		maybe_warnx("%s: unknown suffix -- ignored", file);
1371 		goto lose;
1372 	}
1373 
1374 	rbytes = read(fd, header1, sizeof header1);
1375 	if (rbytes != sizeof header1) {
1376 		/* we don't want to fail here. */
1377 #ifndef SMALL
1378 		if (fflag)
1379 			goto lose;
1380 #endif
1381 		if (rbytes == -1)
1382 			maybe_warn("can't read %s", file);
1383 		else
1384 			goto unexpected_EOF;
1385 		goto lose;
1386 	}
1387 
1388 	method = file_gettype(header1);
1389 #ifndef SMALL
1390 	if (fflag == 0 && method == FT_UNKNOWN) {
1391 		maybe_warnx("%s: not in gzip format", file);
1392 		goto lose;
1393 	}
1394 
1395 #endif
1396 
1397 #ifndef SMALL
1398 	if (method == FT_GZIP && Nflag) {
1399 		unsigned char ts[4];	/* timestamp */
1400 
1401 		rv = pread(fd, ts, sizeof ts, GZIP_TIMESTAMP);
1402 		if (rv >= 0 && rv < (ssize_t)(sizeof ts))
1403 			goto unexpected_EOF;
1404 		if (rv == -1) {
1405 			if (!fflag)
1406 				maybe_warn("can't read %s", file);
1407 			goto lose;
1408 		}
1409 		timestamp = ts[3] << 24 | ts[2] << 16 | ts[1] << 8 | ts[0];
1410 
1411 		if (header1[3] & ORIG_NAME) {
1412 			rbytes = pread(fd, name, sizeof name, GZIP_ORIGNAME);
1413 			if (rbytes < 0) {
1414 				maybe_warn("can't read %s", file);
1415 				goto lose;
1416 			}
1417 			if (name[0] != 0) {
1418 				/* preserve original directory name */
1419 				char *dp = strrchr(file, '/');
1420 				if (dp == NULL)
1421 					dp = file;
1422 				else
1423 					dp++;
1424 				snprintf(outfile, outsize, "%.*s%.*s",
1425 						(int) (dp - file),
1426 						file, (int) rbytes, name);
1427 			}
1428 		}
1429 	}
1430 #endif
1431 	lseek(fd, 0, SEEK_SET);
1432 
1433 	if (cflag == 0 || lflag) {
1434 		if (fstat(fd, &isb) != 0)
1435 			goto lose;
1436 #ifndef SMALL
1437 		if (isb.st_nlink > 1 && lflag == 0 && fflag == 0) {
1438 			maybe_warnx("%s has %d other links -- skipping",
1439 			    file, isb.st_nlink - 1);
1440 			goto lose;
1441 		}
1442 		if (nflag == 0 && timestamp)
1443 			isb.st_mtime = timestamp;
1444 		if (check_outfile(outfile) == 0)
1445 			goto lose;
1446 #endif
1447 	}
1448 
1449 	if (cflag == 0 && lflag == 0) {
1450 		zfd = open(outfile, O_WRONLY|O_CREAT|O_EXCL, 0600);
1451 		if (zfd == STDOUT_FILENO) {
1452 			/* We won't close STDOUT_FILENO later... */
1453 			zfd = dup(zfd);
1454 			close(STDOUT_FILENO);
1455 		}
1456 		if (zfd == -1) {
1457 			maybe_warn("can't open %s", outfile);
1458 			goto lose;
1459 		}
1460 #ifndef SMALL
1461 		remove_file = outfile;
1462 #endif
1463 	} else
1464 		zfd = STDOUT_FILENO;
1465 
1466 	switch (method) {
1467 #ifndef NO_BZIP2_SUPPORT
1468 	case FT_BZIP2:
1469 		/* XXX */
1470 		if (lflag) {
1471 			maybe_warnx("no -l with bzip2 files");
1472 			goto lose;
1473 		}
1474 
1475 		size = unbzip2(fd, zfd, NULL, 0, NULL);
1476 		break;
1477 #endif
1478 
1479 #ifndef NO_COMPRESS_SUPPORT
1480 	case FT_Z: {
1481 		FILE *in, *out;
1482 
1483 		/* XXX */
1484 		if (lflag) {
1485 			maybe_warnx("no -l with Lempel-Ziv files");
1486 			goto lose;
1487 		}
1488 
1489 		if ((in = zdopen(fd)) == NULL) {
1490 			maybe_warn("zdopen for read: %s", file);
1491 			goto lose;
1492 		}
1493 
1494 		out = fdopen(dup(zfd), "w");
1495 		if (out == NULL) {
1496 			maybe_warn("fdopen for write: %s", outfile);
1497 			fclose(in);
1498 			goto lose;
1499 		}
1500 
1501 		size = zuncompress(in, out, NULL, 0, NULL);
1502 		/* need to fclose() if ferror() is true... */
1503 		if (ferror(in) | fclose(in)) {
1504 			maybe_warn("failed infile fclose");
1505 			unlink(outfile);
1506 			(void)fclose(out);
1507 		}
1508 		if (fclose(out) != 0) {
1509 			maybe_warn("failed outfile fclose");
1510 			unlink(outfile);
1511 			goto lose;
1512 		}
1513 		break;
1514 	}
1515 #endif
1516 
1517 #ifndef NO_PACK_SUPPORT
1518 	case FT_PACK:
1519 		if (lflag) {
1520 			maybe_warnx("no -l with packed files");
1521 			goto lose;
1522 		}
1523 
1524 		size = unpack(fd, zfd, NULL, 0, NULL);
1525 		break;
1526 #endif
1527 
1528 #ifndef NO_XZ_SUPPORT
1529 	case FT_XZ:
1530 		if (lflag) {
1531 			maybe_warnx("no -l with xz files");
1532 			goto lose;
1533 		}
1534 
1535 		size = unxz(fd, zfd, NULL, 0, NULL);
1536 		break;
1537 #endif
1538 
1539 #ifndef SMALL
1540 	case FT_UNKNOWN:
1541 		if (lflag) {
1542 			maybe_warnx("no -l for unknown filetypes");
1543 			goto lose;
1544 		}
1545 		size = cat_fd(NULL, 0, NULL, fd);
1546 		break;
1547 #endif
1548 	default:
1549 		if (lflag) {
1550 			print_list(fd, isb.st_size, outfile, isb.st_mtime);
1551 			close(fd);
1552 			return -1;	/* XXX */
1553 		}
1554 
1555 		size = gz_uncompress(fd, zfd, NULL, 0, NULL, file);
1556 		break;
1557 	}
1558 
1559 	if (close(fd) != 0)
1560 		maybe_warn("couldn't close input");
1561 	if (zfd != STDOUT_FILENO && close(zfd) != 0)
1562 		maybe_warn("couldn't close output");
1563 
1564 	if (size == -1) {
1565 		if (cflag == 0)
1566 			unlink(outfile);
1567 		maybe_warnx("%s: uncompress failed", file);
1568 		return -1;
1569 	}
1570 
1571 	/* if testing, or we uncompressed to stdout, this is all we need */
1572 #ifndef SMALL
1573 	if (tflag)
1574 		return size;
1575 #endif
1576 	/* if we are uncompressing to stdin, don't remove the file. */
1577 	if (cflag)
1578 		return size;
1579 
1580 	/*
1581 	 * if we create a file...
1582 	 */
1583 	/*
1584 	 * if we can't stat the file don't remove the file.
1585 	 */
1586 
1587 	ofd = open(outfile, O_RDWR, 0);
1588 	if (ofd == -1) {
1589 		maybe_warn("couldn't open (leaving original): %s",
1590 			   outfile);
1591 		return -1;
1592 	}
1593 	if (fstat(ofd, &osb) != 0) {
1594 		maybe_warn("couldn't stat (leaving original): %s",
1595 			   outfile);
1596 		close(ofd);
1597 		return -1;
1598 	}
1599 	if (osb.st_size != size) {
1600 		maybe_warnx("stat gave different size: %ju != %ju (leaving original)",
1601 		    (uintmax_t)size, (uintmax_t)osb.st_size);
1602 		close(ofd);
1603 		unlink(outfile);
1604 		return -1;
1605 	}
1606 #ifndef SMALL
1607 	copymodes(ofd, &isb, outfile);
1608 	remove_file = NULL;
1609 #endif
1610 	close(ofd);
1611 	unlink_input(file, &isb);
1612 	return size;
1613 
1614     unexpected_EOF:
1615 	maybe_warnx("%s: unexpected end of file", file);
1616     lose:
1617 	if (fd != -1)
1618 		close(fd);
1619 	if (zfd != -1 && zfd != STDOUT_FILENO)
1620 		close(fd);
1621 	return -1;
1622 }
1623 
1624 #ifndef SMALL
1625 static off_t
1626 cat_fd(unsigned char * prepend, size_t count, off_t *gsizep, int fd)
1627 {
1628 	char buf[BUFLEN];
1629 	off_t in_tot;
1630 	ssize_t w;
1631 
1632 	in_tot = count;
1633 	w = write(STDOUT_FILENO, prepend, count);
1634 	if (w == -1 || (size_t)w != count) {
1635 		maybe_warn("write to stdout");
1636 		return -1;
1637 	}
1638 	for (;;) {
1639 		ssize_t rv;
1640 
1641 		rv = read(fd, buf, sizeof buf);
1642 		if (rv == 0)
1643 			break;
1644 		if (rv < 0) {
1645 			maybe_warn("read from fd %d", fd);
1646 			break;
1647 		}
1648 
1649 		if (write(STDOUT_FILENO, buf, rv) != rv) {
1650 			maybe_warn("write to stdout");
1651 			break;
1652 		}
1653 		in_tot += rv;
1654 	}
1655 
1656 	if (gsizep)
1657 		*gsizep = in_tot;
1658 	return (in_tot);
1659 }
1660 #endif
1661 
1662 static void
1663 handle_stdin(void)
1664 {
1665 	unsigned char header1[4];
1666 	off_t usize, gsize;
1667 	enum filetype method;
1668 	ssize_t bytes_read;
1669 #ifndef NO_COMPRESS_SUPPORT
1670 	FILE *in;
1671 #endif
1672 
1673 #ifndef SMALL
1674 	if (fflag == 0 && lflag == 0 && isatty(STDIN_FILENO)) {
1675 		maybe_warnx("standard input is a terminal -- ignoring");
1676 		return;
1677 	}
1678 #endif
1679 
1680 	if (lflag) {
1681 		struct stat isb;
1682 
1683 		/* XXX could read the whole file, etc. */
1684 		if (fstat(STDIN_FILENO, &isb) < 0) {
1685 			maybe_warn("fstat");
1686 			return;
1687 		}
1688 		print_list(STDIN_FILENO, isb.st_size, "stdout", isb.st_mtime);
1689 		return;
1690 	}
1691 
1692 	bytes_read = read_retry(STDIN_FILENO, header1, sizeof header1);
1693 	if (bytes_read == -1) {
1694 		maybe_warn("can't read stdin");
1695 		return;
1696 	} else if (bytes_read != sizeof(header1)) {
1697 		maybe_warnx("(stdin): unexpected end of file");
1698 		return;
1699 	}
1700 
1701 	method = file_gettype(header1);
1702 	switch (method) {
1703 	default:
1704 #ifndef SMALL
1705 		if (fflag == 0) {
1706 			maybe_warnx("unknown compression format");
1707 			return;
1708 		}
1709 		usize = cat_fd(header1, sizeof header1, &gsize, STDIN_FILENO);
1710 		break;
1711 #endif
1712 	case FT_GZIP:
1713 		usize = gz_uncompress(STDIN_FILENO, STDOUT_FILENO,
1714 			      (char *)header1, sizeof header1, &gsize, "(stdin)");
1715 		break;
1716 #ifndef NO_BZIP2_SUPPORT
1717 	case FT_BZIP2:
1718 		usize = unbzip2(STDIN_FILENO, STDOUT_FILENO,
1719 				(char *)header1, sizeof header1, &gsize);
1720 		break;
1721 #endif
1722 #ifndef NO_COMPRESS_SUPPORT
1723 	case FT_Z:
1724 		if ((in = zdopen(STDIN_FILENO)) == NULL) {
1725 			maybe_warnx("zopen of stdin");
1726 			return;
1727 		}
1728 
1729 		usize = zuncompress(in, stdout, (char *)header1,
1730 		    sizeof header1, &gsize);
1731 		fclose(in);
1732 		break;
1733 #endif
1734 #ifndef NO_PACK_SUPPORT
1735 	case FT_PACK:
1736 		usize = unpack(STDIN_FILENO, STDOUT_FILENO,
1737 			       (char *)header1, sizeof header1, &gsize);
1738 		break;
1739 #endif
1740 #ifndef NO_XZ_SUPPORT
1741 	case FT_XZ:
1742 		usize = unxz(STDIN_FILENO, STDOUT_FILENO,
1743 			     (char *)header1, sizeof header1, &gsize);
1744 		break;
1745 #endif
1746 	}
1747 
1748 #ifndef SMALL
1749         if (vflag && !tflag && usize != -1 && gsize != -1)
1750 		print_verbage(NULL, NULL, usize, gsize);
1751 	if (vflag && tflag)
1752 		print_test("(stdin)", usize != -1);
1753 #endif
1754 
1755 }
1756 
1757 static void
1758 handle_stdout(void)
1759 {
1760 	off_t gsize, usize;
1761 	struct stat sb;
1762 	time_t systime;
1763 	uint32_t mtime;
1764 	int ret;
1765 
1766 #ifndef SMALL
1767 	if (fflag == 0 && isatty(STDOUT_FILENO)) {
1768 		maybe_warnx("standard output is a terminal -- ignoring");
1769 		return;
1770 	}
1771 #endif
1772 	/* If stdin is a file use it's mtime, otherwise use current time */
1773 	ret = fstat(STDIN_FILENO, &sb);
1774 
1775 #ifndef SMALL
1776 	if (ret < 0) {
1777 		maybe_warn("Can't stat stdin");
1778 		return;
1779 	}
1780 #endif
1781 
1782 	if (S_ISREG(sb.st_mode))
1783 		mtime = (uint32_t)sb.st_mtime;
1784 	else {
1785 		systime = time(NULL);
1786 #ifndef SMALL
1787 		if (systime == -1) {
1788 			maybe_warn("time");
1789 			return;
1790 		}
1791 #endif
1792 		mtime = (uint32_t)systime;
1793 	}
1794 
1795 	usize = gz_compress(STDIN_FILENO, STDOUT_FILENO, &gsize, "", mtime);
1796 #ifndef SMALL
1797         if (vflag && !tflag && usize != -1 && gsize != -1)
1798 		print_verbage(NULL, NULL, usize, gsize);
1799 #endif
1800 }
1801 
1802 /* do what is asked for, for the path name */
1803 static void
1804 handle_pathname(char *path)
1805 {
1806 	char *opath = path, *s = NULL;
1807 	ssize_t len;
1808 	int slen;
1809 	struct stat sb;
1810 
1811 	/* check for stdout/stdin */
1812 	if (path[0] == '-' && path[1] == '\0') {
1813 		if (dflag)
1814 			handle_stdin();
1815 		else
1816 			handle_stdout();
1817 		return;
1818 	}
1819 
1820 retry:
1821 	if (stat(path, &sb) != 0 || (fflag == 0 && cflag == 0 &&
1822 	    lstat(path, &sb) != 0)) {
1823 		/* lets try <path>.gz if we're decompressing */
1824 		if (dflag && s == NULL && errno == ENOENT) {
1825 			len = strlen(path);
1826 			slen = suffixes[0].ziplen;
1827 			s = malloc(len + slen + 1);
1828 			if (s == NULL)
1829 				maybe_err("malloc");
1830 			memcpy(s, path, len);
1831 			memcpy(s + len, suffixes[0].zipped, slen + 1);
1832 			path = s;
1833 			goto retry;
1834 		}
1835 		maybe_warn("can't stat: %s", opath);
1836 		goto out;
1837 	}
1838 
1839 	if (S_ISDIR(sb.st_mode)) {
1840 #ifndef SMALL
1841 		if (rflag)
1842 			handle_dir(path);
1843 		else
1844 #endif
1845 			maybe_warnx("%s is a directory", path);
1846 		goto out;
1847 	}
1848 
1849 	if (S_ISREG(sb.st_mode))
1850 		handle_file(path, &sb);
1851 	else
1852 		maybe_warnx("%s is not a regular file", path);
1853 
1854 out:
1855 	if (s)
1856 		free(s);
1857 }
1858 
1859 /* compress/decompress a file */
1860 static void
1861 handle_file(char *file, struct stat *sbp)
1862 {
1863 	off_t usize, gsize;
1864 	char	outfile[PATH_MAX];
1865 
1866 	infile = file;
1867 	if (dflag) {
1868 		usize = file_uncompress(file, outfile, sizeof(outfile));
1869 #ifndef SMALL
1870 		if (vflag && tflag)
1871 			print_test(file, usize != -1);
1872 #endif
1873 		if (usize == -1)
1874 			return;
1875 		gsize = sbp->st_size;
1876 	} else {
1877 		gsize = file_compress(file, outfile, sizeof(outfile));
1878 		if (gsize == -1)
1879 			return;
1880 		usize = sbp->st_size;
1881 	}
1882 
1883 
1884 #ifndef SMALL
1885 	if (vflag && !tflag)
1886 		print_verbage(file, (cflag) ? NULL : outfile, usize, gsize);
1887 #endif
1888 }
1889 
1890 #ifndef SMALL
1891 /* this is used with -r to recursively descend directories */
1892 static void
1893 handle_dir(char *dir)
1894 {
1895 	char *path_argv[2];
1896 	FTS *fts;
1897 	FTSENT *entry;
1898 
1899 	path_argv[0] = dir;
1900 	path_argv[1] = 0;
1901 	fts = fts_open(path_argv, FTS_PHYSICAL | FTS_NOCHDIR, NULL);
1902 	if (fts == NULL) {
1903 		warn("couldn't fts_open %s", dir);
1904 		return;
1905 	}
1906 
1907 	while ((entry = fts_read(fts))) {
1908 		switch(entry->fts_info) {
1909 		case FTS_D:
1910 		case FTS_DP:
1911 			continue;
1912 
1913 		case FTS_DNR:
1914 		case FTS_ERR:
1915 		case FTS_NS:
1916 			maybe_warn("%s", entry->fts_path);
1917 			continue;
1918 		case FTS_F:
1919 			handle_file(entry->fts_path, entry->fts_statp);
1920 		}
1921 	}
1922 	(void)fts_close(fts);
1923 }
1924 #endif
1925 
1926 /* print a ratio - size reduction as a fraction of uncompressed size */
1927 static void
1928 print_ratio(off_t in, off_t out, FILE *where)
1929 {
1930 	int percent10;	/* 10 * percent */
1931 	off_t diff;
1932 	char buff[8];
1933 	int len;
1934 
1935 	diff = in - out/2;
1936 	if (diff <= 0)
1937 		/*
1938 		 * Output is more than double size of input! print -99.9%
1939 		 * Quite possibly we've failed to get the original size.
1940 		 */
1941 		percent10 = -999;
1942 	else {
1943 		/*
1944 		 * We only need 12 bits of result from the final division,
1945 		 * so reduce the values until a 32bit division will suffice.
1946 		 */
1947 		while (in > 0x100000) {
1948 			diff >>= 1;
1949 			in >>= 1;
1950 		}
1951 		if (in != 0)
1952 			percent10 = ((u_int)diff * 2000) / (u_int)in - 1000;
1953 		else
1954 			percent10 = 0;
1955 	}
1956 
1957 	len = snprintf(buff, sizeof buff, "%2.2d.", percent10);
1958 	/* Move the '.' to before the last digit */
1959 	buff[len - 1] = buff[len - 2];
1960 	buff[len - 2] = '.';
1961 	fprintf(where, "%5s%%", buff);
1962 }
1963 
1964 #ifndef SMALL
1965 /* print compression statistics, and the new name (if there is one!) */
1966 static void
1967 print_verbage(const char *file, const char *nfile, off_t usize, off_t gsize)
1968 {
1969 	if (file)
1970 		fprintf(stderr, "%s:%s  ", file,
1971 		    strlen(file) < 7 ? "\t\t" : "\t");
1972 	print_ratio(usize, gsize, stderr);
1973 	if (nfile)
1974 		fprintf(stderr, " -- replaced with %s", nfile);
1975 	fprintf(stderr, "\n");
1976 	fflush(stderr);
1977 }
1978 
1979 /* print test results */
1980 static void
1981 print_test(const char *file, int ok)
1982 {
1983 
1984 	if (exit_value == 0 && ok == 0)
1985 		exit_value = 1;
1986 	fprintf(stderr, "%s:%s  %s\n", file,
1987 	    strlen(file) < 7 ? "\t\t" : "\t", ok ? "OK" : "NOT OK");
1988 	fflush(stderr);
1989 }
1990 #endif
1991 
1992 /* print a file's info ala --list */
1993 /* eg:
1994   compressed uncompressed  ratio uncompressed_name
1995       354841      1679360  78.8% /usr/pkgsrc/distfiles/libglade-2.0.1.tar
1996 */
1997 static void
1998 print_list(int fd, off_t out, const char *outfile, time_t ts)
1999 {
2000 	static int first = 1;
2001 #ifndef SMALL
2002 	static off_t in_tot, out_tot;
2003 	uint32_t crc = 0;
2004 #endif
2005 	off_t in = 0, rv;
2006 
2007 	if (first) {
2008 #ifndef SMALL
2009 		if (vflag)
2010 			printf("method  crc     date  time  ");
2011 #endif
2012 		if (qflag == 0)
2013 			printf("  compressed uncompressed  "
2014 			       "ratio uncompressed_name\n");
2015 	}
2016 	first = 0;
2017 
2018 	/* print totals? */
2019 #ifndef SMALL
2020 	if (fd == -1) {
2021 		in = in_tot;
2022 		out = out_tot;
2023 	} else
2024 #endif
2025 	{
2026 		/* read the last 4 bytes - this is the uncompressed size */
2027 		rv = lseek(fd, (off_t)(-8), SEEK_END);
2028 		if (rv != -1) {
2029 			unsigned char buf[8];
2030 			uint32_t usize;
2031 
2032 			rv = read(fd, (char *)buf, sizeof(buf));
2033 			if (rv == -1)
2034 				maybe_warn("read of uncompressed size");
2035 			else if (rv != sizeof(buf))
2036 				maybe_warnx("read of uncompressed size");
2037 
2038 			else {
2039 				usize = buf[4] | buf[5] << 8 |
2040 					buf[6] << 16 | buf[7] << 24;
2041 				in = (off_t)usize;
2042 #ifndef SMALL
2043 				crc = buf[0] | buf[1] << 8 |
2044 				      buf[2] << 16 | buf[3] << 24;
2045 #endif
2046 			}
2047 		}
2048 	}
2049 
2050 #ifndef SMALL
2051 	if (vflag && fd == -1)
2052 		printf("                            ");
2053 	else if (vflag) {
2054 		char *date = ctime(&ts);
2055 
2056 		/* skip the day, 1/100th second, and year */
2057 		date += 4;
2058 		date[12] = 0;
2059 		printf("%5s %08x %11s ", "defla"/*XXX*/, crc, date);
2060 	}
2061 	in_tot += in;
2062 	out_tot += out;
2063 #else
2064 	(void)&ts;	/* XXX */
2065 #endif
2066 	printf("%12llu %12llu ", (unsigned long long)out, (unsigned long long)in);
2067 	print_ratio(in, out, stdout);
2068 	printf(" %s\n", outfile);
2069 }
2070 
2071 /* display the usage of NetBSD gzip */
2072 static void
2073 usage(void)
2074 {
2075 
2076 	fprintf(stderr, "%s\n", gzip_version);
2077 	fprintf(stderr,
2078 #ifdef SMALL
2079     "usage: %s [-" OPT_LIST "] [<file> [<file> ...]]\n",
2080 #else
2081     "usage: %s [-123456789acdfhklLNnqrtVv] [-S .suffix] [<file> [<file> ...]]\n"
2082     " -1 --fast            fastest (worst) compression\n"
2083     " -2 .. -8             set compression level\n"
2084     " -9 --best            best (slowest) compression\n"
2085     " -c --stdout          write to stdout, keep original files\n"
2086     "    --to-stdout\n"
2087     " -d --decompress      uncompress files\n"
2088     "    --uncompress\n"
2089     " -f --force           force overwriting & compress links\n"
2090     " -h --help            display this help\n"
2091     " -k --keep            don't delete input files during operation\n"
2092     " -l --list            list compressed file contents\n"
2093     " -N --name            save or restore original file name and time stamp\n"
2094     " -n --no-name         don't save original file name or time stamp\n"
2095     " -q --quiet           output no warnings\n"
2096     " -r --recursive       recursively compress files in directories\n"
2097     " -S .suf              use suffix .suf instead of .gz\n"
2098     "    --suffix .suf\n"
2099     " -t --test            test compressed file\n"
2100     " -V --version         display program version\n"
2101     " -v --verbose         print extra statistics\n",
2102 #endif
2103 	    getprogname());
2104 	exit(0);
2105 }
2106 
2107 #ifndef SMALL
2108 /* display the license information of FreeBSD gzip */
2109 static void
2110 display_license(void)
2111 {
2112 
2113 	fprintf(stderr, "%s (based on NetBSD gzip 20111009)\n", gzip_version);
2114 	fprintf(stderr, "%s\n", gzip_copyright);
2115 	exit(0);
2116 }
2117 #endif
2118 
2119 /* display the version of NetBSD gzip */
2120 static void
2121 display_version(void)
2122 {
2123 
2124 	fprintf(stderr, "%s\n", gzip_version);
2125 	exit(0);
2126 }
2127 
2128 #ifndef NO_BZIP2_SUPPORT
2129 #include "unbzip2.c"
2130 #endif
2131 #ifndef NO_COMPRESS_SUPPORT
2132 #include "zuncompress.c"
2133 #endif
2134 #ifndef NO_PACK_SUPPORT
2135 #include "unpack.c"
2136 #endif
2137 #ifndef NO_XZ_SUPPORT
2138 #include "unxz.c"
2139 #endif
2140 
2141 static ssize_t
2142 read_retry(int fd, void *buf, size_t sz)
2143 {
2144 	char *cp = buf;
2145 	size_t left = MIN(sz, (size_t) SSIZE_MAX);
2146 
2147 	while (left > 0) {
2148 		ssize_t ret;
2149 
2150 		ret = read(fd, cp, left);
2151 		if (ret == -1) {
2152 			return ret;
2153 		} else if (ret == 0) {
2154 			break; /* EOF */
2155 		}
2156 		cp += ret;
2157 		left -= ret;
2158 	}
2159 
2160 	return sz - left;
2161 }
2162