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unzip.c revision 1.13
      1 /* $NetBSD: unzip.c,v 1.13 2010/04/29 06:32:19 joerg Exp $ */
      2 
      3 /*-
      4  * Copyright (c) 2009, 2010 Joerg Sonnenberger <joerg (at) NetBSD.org>
      5  * Copyright (c) 2007-2008 Dag-Erling Codan Smrgrav
      6  * All rights reserved.
      7  *
      8  * Redistribution and use in source and binary forms, with or without
      9  * modification, are permitted provided that the following conditions
     10  * are met:
     11  * 1. Redistributions of source code must retain the above copyright
     12  *    notice, this list of conditions and the following disclaimer
     13  *    in this position and unchanged.
     14  * 2. Redistributions in binary form must reproduce the above copyright
     15  *    notice, this list of conditions and the following disclaimer in the
     16  *    documentation and/or other materials provided with the distribution.
     17  *
     18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
     19  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     21  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
     22  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     24  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     25  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     26  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     28  * SUCH DAMAGE.
     29  *
     30  * $FreeBSD: revision 180124$
     31  *
     32  * This file would be much shorter if we didn't care about command-line
     33  * compatibility with Info-ZIP's UnZip, which requires us to duplicate
     34  * parts of libarchive in order to gain more detailed control of its
     35  * behaviour for the purpose of implementing the -n, -o, -L and -a
     36  * options.
     37  */
     38 
     39 #include <sys/cdefs.h>
     40 __RCSID("$NetBSD: unzip.c,v 1.13 2010/04/29 06:32:19 joerg Exp $");
     41 
     42 #include <sys/queue.h>
     43 #include <sys/stat.h>
     44 
     45 #include <ctype.h>
     46 #include <errno.h>
     47 #include <fcntl.h>
     48 #include <fnmatch.h>
     49 #include <stdarg.h>
     50 #include <stdio.h>
     51 #include <stdlib.h>
     52 #include <string.h>
     53 #include <unistd.h>
     54 
     55 #include <archive.h>
     56 #include <archive_entry.h>
     57 
     58 /* command-line options */
     59 static int		 a_opt;		/* convert EOL */
     60 static int		 C_opt;		/* match case-insensitively */
     61 static int		 c_opt;		/* extract to stdout */
     62 static const char	*d_arg;		/* directory */
     63 static int		 f_opt;		/* update existing files only */
     64 static int		 j_opt;		/* junk directories */
     65 static int		 L_opt;		/* lowercase names */
     66 static int		 n_opt;		/* never overwrite */
     67 static int		 o_opt;		/* always overwrite */
     68 static int		 p_opt;		/* extract to stdout, quiet */
     69 static int		 q_opt;		/* quiet */
     70 static int		 t_opt;		/* test */
     71 static int		 u_opt;		/* update */
     72 static int		 v_opt;		/* verbose/list */
     73 
     74 /* time when unzip started */
     75 static time_t		 now;
     76 
     77 /* debug flag */
     78 static int		 unzip_debug;
     79 
     80 /* running on tty? */
     81 static int		 tty;
     82 
     83 /* convenience macro */
     84 /* XXX should differentiate between ARCHIVE_{WARN,FAIL,RETRY} */
     85 #define ac(call)						\
     86 	do {							\
     87 		int acret = (call);				\
     88 		if (acret != ARCHIVE_OK)			\
     89 			errorx("%s", archive_error_string(a));	\
     90 	} while (0)
     91 
     92 /*
     93  * Indicates that last info() did not end with EOL.  This helps error() et
     94  * al. avoid printing an error message on the same line as an incomplete
     95  * informational message.
     96  */
     97 static int noeol;
     98 
     99 /* fatal error message + errno */
    100 static void
    101 error(const char *fmt, ...)
    102 {
    103 	va_list ap;
    104 
    105 	if (noeol)
    106 		fprintf(stdout, "\n");
    107 	fflush(stdout);
    108 	fprintf(stderr, "unzip: ");
    109 	va_start(ap, fmt);
    110 	vfprintf(stderr, fmt, ap);
    111 	va_end(ap);
    112 	fprintf(stderr, ": %s\n", strerror(errno));
    113 	exit(1);
    114 }
    115 
    116 /* fatal error message, no errno */
    117 static void
    118 errorx(const char *fmt, ...)
    119 {
    120 	va_list ap;
    121 
    122 	if (noeol)
    123 		fprintf(stdout, "\n");
    124 	fflush(stdout);
    125 	fprintf(stderr, "unzip: ");
    126 	va_start(ap, fmt);
    127 	vfprintf(stderr, fmt, ap);
    128 	va_end(ap);
    129 	fprintf(stderr, "\n");
    130 	exit(1);
    131 }
    132 
    133 #if 0
    134 /* non-fatal error message + errno */
    135 static void
    136 warning(const char *fmt, ...)
    137 {
    138 	va_list ap;
    139 
    140 	if (noeol)
    141 		fprintf(stdout, "\n");
    142 	fflush(stdout);
    143 	fprintf(stderr, "unzip: ");
    144 	va_start(ap, fmt);
    145 	vfprintf(stderr, fmt, ap);
    146 	va_end(ap);
    147 	fprintf(stderr, ": %s\n", strerror(errno));
    148 }
    149 #endif
    150 
    151 /* non-fatal error message, no errno */
    152 static void
    153 warningx(const char *fmt, ...)
    154 {
    155 	va_list ap;
    156 
    157 	if (noeol)
    158 		fprintf(stdout, "\n");
    159 	fflush(stdout);
    160 	fprintf(stderr, "unzip: ");
    161 	va_start(ap, fmt);
    162 	vfprintf(stderr, fmt, ap);
    163 	va_end(ap);
    164 	fprintf(stderr, "\n");
    165 }
    166 
    167 /* informational message (if not -q) */
    168 static void
    169 info(const char *fmt, ...)
    170 {
    171 	va_list ap;
    172 
    173 	if (q_opt && !unzip_debug)
    174 		return;
    175 	va_start(ap, fmt);
    176 	vfprintf(stdout, fmt, ap);
    177 	va_end(ap);
    178 	fflush(stdout);
    179 
    180 	if (*fmt == '\0')
    181 		noeol = 1;
    182 	else
    183 		noeol = fmt[strlen(fmt) - 1] != '\n';
    184 }
    185 
    186 /* debug message (if unzip_debug) */
    187 static void
    188 debug(const char *fmt, ...)
    189 {
    190 	va_list ap;
    191 
    192 	if (!unzip_debug)
    193 		return;
    194 	va_start(ap, fmt);
    195 	vfprintf(stderr, fmt, ap);
    196 	va_end(ap);
    197 	fflush(stderr);
    198 
    199 	if (*fmt == '\0')
    200 		noeol = 1;
    201 	else
    202 		noeol = fmt[strlen(fmt) - 1] != '\n';
    203 }
    204 
    205 /* duplicate a path name, possibly converting to lower case */
    206 static char *
    207 pathdup(const char *path)
    208 {
    209 	char *str;
    210 	size_t i, len;
    211 
    212 	len = strlen(path);
    213 	while (len && path[len - 1] == '/')
    214 		len--;
    215 	if ((str = malloc(len + 1)) == NULL) {
    216 		errno = ENOMEM;
    217 		error("malloc()");
    218 	}
    219 	if (L_opt) {
    220 		for (i = 0; i < len; ++i)
    221 			str[i] = tolower((unsigned char)path[i]);
    222 	} else {
    223 		memcpy(str, path, len);
    224 	}
    225 	str[len] = '\0';
    226 
    227 	return (str);
    228 }
    229 
    230 /* concatenate two path names */
    231 static char *
    232 pathcat(const char *prefix, const char *path)
    233 {
    234 	char *str;
    235 	size_t prelen, len;
    236 
    237 	prelen = prefix ? strlen(prefix) + 1 : 0;
    238 	len = strlen(path) + 1;
    239 	if ((str = malloc(prelen + len)) == NULL) {
    240 		errno = ENOMEM;
    241 		error("malloc()");
    242 	}
    243 	if (prefix) {
    244 		memcpy(str, prefix, prelen);	/* includes zero */
    245 		str[prelen - 1] = '/';		/* splat zero */
    246 	}
    247 	memcpy(str + prelen, path, len);	/* includes zero */
    248 
    249 	return (str);
    250 }
    251 
    252 /*
    253  * Pattern lists for include / exclude processing
    254  */
    255 struct pattern {
    256 	STAILQ_ENTRY(pattern) link;
    257 	char pattern[];
    258 };
    259 
    260 STAILQ_HEAD(pattern_list, pattern);
    261 static struct pattern_list include = STAILQ_HEAD_INITIALIZER(include);
    262 static struct pattern_list exclude = STAILQ_HEAD_INITIALIZER(exclude);
    263 
    264 /*
    265  * Add an entry to a pattern list
    266  */
    267 static void
    268 add_pattern(struct pattern_list *list, const char *pattern)
    269 {
    270 	struct pattern *entry;
    271 	size_t len;
    272 
    273 	debug("adding pattern '%s'\n", pattern);
    274 	len = strlen(pattern);
    275 	if ((entry = malloc(sizeof *entry + len + 1)) == NULL) {
    276 		errno = ENOMEM;
    277 		error("malloc()");
    278 	}
    279 	memcpy(entry->pattern, pattern, len + 1);
    280 	STAILQ_INSERT_TAIL(list, entry, link);
    281 }
    282 
    283 /*
    284  * Match a string against a list of patterns
    285  */
    286 static int
    287 match_pattern(struct pattern_list *list, const char *str)
    288 {
    289 	struct pattern *entry;
    290 
    291 	STAILQ_FOREACH(entry, list, link) {
    292 		if (fnmatch(entry->pattern, str, C_opt ? FNM_CASEFOLD : 0) == 0)
    293 			return (1);
    294 	}
    295 	return (0);
    296 }
    297 
    298 /*
    299  * Verify that a given pathname is in the include list and not in the
    300  * exclude list.
    301  */
    302 static int
    303 accept_pathname(const char *pathname)
    304 {
    305 
    306 	if (!STAILQ_EMPTY(&include) && !match_pattern(&include, pathname))
    307 		return (0);
    308 	if (!STAILQ_EMPTY(&exclude) && match_pattern(&exclude, pathname))
    309 		return (0);
    310 	return (1);
    311 }
    312 
    313 /*
    314  * Create the specified directory with the specified mode, taking certain
    315  * precautions on they way.
    316  */
    317 static void
    318 make_dir(const char *path, int mode)
    319 {
    320 	struct stat sb;
    321 
    322 	if (lstat(path, &sb) == 0) {
    323 		if (S_ISDIR(sb.st_mode))
    324 			return;
    325 		/*
    326 		 * Normally, we should either ask the user about removing
    327 		 * the non-directory of the same name as a directory we
    328 		 * wish to create, or respect the -n or -o command-line
    329 		 * options.  However, this may lead to a later failure or
    330 		 * even compromise (if this non-directory happens to be a
    331 		 * symlink to somewhere unsafe), so we don't.
    332 		 */
    333 
    334 		/*
    335 		 * Don't check unlink() result; failure will cause mkdir()
    336 		 * to fail later, which we will catch.
    337 		 */
    338 		(void)unlink(path);
    339 	}
    340 	if (mkdir(path, mode) != 0 && errno != EEXIST)
    341 		error("mkdir('%s')", path);
    342 }
    343 
    344 /*
    345  * Ensure that all directories leading up to (but not including) the
    346  * specified path exist.
    347  *
    348  * XXX inefficient + modifies the file in-place
    349  */
    350 static void
    351 make_parent(char *path)
    352 {
    353 	struct stat sb;
    354 	char *sep;
    355 
    356 	sep = strrchr(path, '/');
    357 	if (sep == NULL || sep == path)
    358 		return;
    359 	*sep = '\0';
    360 	if (lstat(path, &sb) == 0) {
    361 		if (S_ISDIR(sb.st_mode)) {
    362 			*sep = '/';
    363 			return;
    364 		}
    365 		unlink(path);
    366 	}
    367 	make_parent(path);
    368 	mkdir(path, 0755);
    369 	*sep = '/';
    370 
    371 #if 0
    372 	for (sep = path; (sep = strchr(sep, '/')) != NULL; sep++) {
    373 		/* root in case of absolute d_arg */
    374 		if (sep == path)
    375 			continue;
    376 		*sep = '\0';
    377 		make_dir(path, 0755);
    378 		*sep = '/';
    379 	}
    380 #endif
    381 }
    382 
    383 /*
    384  * Extract a directory.
    385  */
    386 static void
    387 extract_dir(struct archive *a, struct archive_entry *e, const char *path)
    388 {
    389 	int mode;
    390 
    391 	mode = archive_entry_mode(e) & 0777;
    392 	if (mode == 0)
    393 		mode = 0755;
    394 
    395 	/*
    396 	 * Some zipfiles contain directories with weird permissions such
    397 	 * as 0644 or 0444.  This can cause strange issues such as being
    398 	 * unable to extract files into the directory we just created, or
    399 	 * the user being unable to remove the directory later without
    400 	 * first manually changing its permissions.  Therefore, we whack
    401 	 * the permissions into shape, assuming that the user wants full
    402 	 * access and that anyone who gets read access also gets execute
    403 	 * access.
    404 	 */
    405 	mode |= 0700;
    406 	if (mode & 0040)
    407 		mode |= 0010;
    408 	if (mode & 0004)
    409 		mode |= 0001;
    410 
    411 	info("   creating: %s/\n", path);
    412 	make_dir(path, mode);
    413 	ac(archive_read_data_skip(a));
    414 }
    415 
    416 static unsigned char buffer[8192];
    417 static char spinner[] = { '|', '/', '-', '\\' };
    418 
    419 static int
    420 handle_existing_file(char **path)
    421 {
    422 	size_t alen;
    423 	ssize_t len;
    424 	char buf[4];
    425 
    426 	for (;;) {
    427 		fprintf(stderr,
    428 		    "replace %s? [y]es, [n]o, [A]ll, [N]one, [r]ename: ",
    429 		    *path);
    430 		fgets(buf, 4, stdin);
    431 		switch (*buf) {
    432 		case 'A':
    433 			o_opt = 1;
    434 			/* FALL THROUGH */
    435 		case 'y':
    436 		case 'Y':
    437 			(void)unlink(*path);
    438 			return 1;
    439 		case 'N':
    440 			n_opt = 1;
    441 			/* FALL THROUGH */
    442 		case 'n':
    443 			return -1;
    444 		case 'r':
    445 		case 'R':
    446 			printf("New name: ");
    447 			fflush(stdout);
    448 			free(*path);
    449 			*path = NULL;
    450 			alen = 0;
    451 			len = getline(path, &alen, stdin);
    452 			if ((*path)[len - 1] != '\n')
    453 				(*path)[len - 1] = '\0';
    454 			return 0;
    455 		default:
    456 			break;
    457 		}
    458 	}
    459 }
    460 
    461 /*
    462  * Detect binary files by a combination of character white list and
    463  * black list. NUL bytes and other control codes without use in text files
    464  * result directly in switching the file to binary mode. Otherwise, at least
    465  * one white-listed byte has to be found.
    466  *
    467  * Black-listed: 0..6, 14..25, 28..31
    468  * White-listed: 9..10, 13, >= 32
    469  *
    470  * See the proginfo/txtvsbin.txt in the zip sources for a detailed discussion.
    471  */
    472 #define BYTE_IS_BINARY(x)	((x) < 32 && (0xf3ffc07fU & (1U << (x))))
    473 #define	BYTE_IS_TEXT(x)		((x) >= 32 || (0x00002600U & (1U << (x))))
    474 
    475 static int
    476 check_binary(const unsigned char *buf, size_t len)
    477 {
    478 	int rv;
    479 	for (rv = 1; len--; ++buf) {
    480 		if (BYTE_IS_BINARY(*buf))
    481 			return 1;
    482 		if (BYTE_IS_TEXT(*buf))
    483 			rv = 0;
    484 	}
    485 
    486 	return rv;
    487 }
    488 
    489 /*
    490  * Extract a regular file.
    491  */
    492 static void
    493 extract_file(struct archive *a, struct archive_entry *e, char **path)
    494 {
    495 	int mode;
    496 	time_t mtime;
    497 	struct stat sb;
    498 	struct timeval tv[2];
    499 	int cr, fd, text, warn, check;
    500 	ssize_t len;
    501 	unsigned char *p, *q, *end;
    502 
    503 	mode = archive_entry_mode(e) & 0777;
    504 	if (mode == 0)
    505 		mode = 0644;
    506 	mtime = archive_entry_mtime(e);
    507 
    508 	/* look for existing file of same name */
    509 recheck:
    510 	if (lstat(*path, &sb) == 0) {
    511 		if (u_opt || f_opt) {
    512 			/* check if up-to-date */
    513 			if (S_ISREG(sb.st_mode) && sb.st_mtime >= mtime)
    514 				return;
    515 			(void)unlink(*path);
    516 		} else if (o_opt) {
    517 			/* overwrite */
    518 			(void)unlink(*path);
    519 		} else if (n_opt) {
    520 			/* do not overwrite */
    521 			return;
    522 		} else {
    523 			check = handle_existing_file(path);
    524 			if (check == 0)
    525 				goto recheck;
    526 			if (check == -1)
    527 				return; /* do not overwrite */
    528 		}
    529 	} else {
    530 		if (f_opt)
    531 			return;
    532 	}
    533 
    534 	if ((fd = open(*path, O_RDWR|O_CREAT|O_TRUNC, mode)) < 0)
    535 		error("open('%s')", *path);
    536 
    537 	/* loop over file contents and write to disk */
    538 	info(" extracting: %s", *path);
    539 	text = a_opt;
    540 	warn = 0;
    541 	cr = 0;
    542 	for (int n = 0; ; n++) {
    543 		if (tty && (n % 4) == 0)
    544 			info(" %c\b\b", spinner[(n / 4) % sizeof spinner]);
    545 
    546 		len = archive_read_data(a, buffer, sizeof buffer);
    547 
    548 		if (len < 0)
    549 			ac(len);
    550 
    551 		/* left over CR from previous buffer */
    552 		if (a_opt && cr) {
    553 			if (len == 0 || buffer[0] != '\n')
    554 				if (write(fd, "\r", 1) != 1)
    555 					error("write('%s')", *path);
    556 			cr = 0;
    557 		}
    558 
    559 		/* EOF */
    560 		if (len == 0)
    561 			break;
    562 		end = buffer + len;
    563 
    564 		/*
    565 		 * Detect whether this is a text file.  The correct way to
    566 		 * do this is to check the least significant bit of the
    567 		 * "internal file attributes" field of the corresponding
    568 		 * file header in the central directory, but libarchive
    569 		 * does not read the central directory, so we have to
    570 		 * guess by looking for non-ASCII characters in the
    571 		 * buffer.  Hopefully we won't guess wrong.  If we do
    572 		 * guess wrong, we print a warning message later.
    573 		 */
    574 		if (a_opt && n == 0) {
    575 			if (check_binary(buffer, len)) {
    576 				text = 0;
    577 				break;
    578 			}
    579 		}
    580 
    581 		/* simple case */
    582 		if (!a_opt || !text) {
    583 			if (write(fd, buffer, len) != len)
    584 				error("write('%s')", path);
    585 			continue;
    586 		}
    587 
    588 		/* hard case: convert \r\n to \n (sigh...) */
    589 		for (p = buffer; p < end; p = q + 1) {
    590 			for (q = p; q < end; q++) {
    591 				if (!warn && BYTE_IS_BINARY(*q)) {
    592 					warningx("%s may be corrupted due"
    593 					    " to weak text file detection"
    594 					    " heuristic", *path);
    595 					warn = 1;
    596 				}
    597 				if (q[0] != '\r')
    598 					continue;
    599 				if (&q[1] == end) {
    600 					cr = 1;
    601 					break;
    602 				}
    603 				if (q[1] == '\n')
    604 					break;
    605 			}
    606 			if (write(fd, p, q - p) != q - p)
    607 				error("write('%s')", *path);
    608 		}
    609 	}
    610 	if (tty)
    611 		info("  \b\b");
    612 	if (text)
    613 		info(" (text)");
    614 	info("\n");
    615 
    616 	/* set access and modification time */
    617 	tv[0].tv_sec = now;
    618 	tv[0].tv_usec = 0;
    619 	tv[1].tv_sec = mtime;
    620 	tv[1].tv_usec = 0;
    621 	if (futimes(fd, tv) != 0)
    622 		error("utimes('%s')", *path);
    623 	if (close(fd) != 0)
    624 		error("close('%s')", *path);
    625 }
    626 
    627 /*
    628  * Extract a zipfile entry: first perform some sanity checks to ensure
    629  * that it is either a directory or a regular file and that the path is
    630  * not absolute and does not try to break out of the current directory;
    631  * then call either extract_dir() or extract_file() as appropriate.
    632  *
    633  * This is complicated a bit by the various ways in which we need to
    634  * manipulate the path name.  Case conversion (if requested by the -L
    635  * option) happens first, but the include / exclude patterns are applied
    636  * to the full converted path name, before the directory part of the path
    637  * is removed in accordance with the -j option.  Sanity checks are
    638  * intentionally done earlier than they need to be, so the user will get a
    639  * warning about insecure paths even for files or directories which
    640  * wouldn't be extracted anyway.
    641  */
    642 static void
    643 extract(struct archive *a, struct archive_entry *e)
    644 {
    645 	char *pathname, *realpathname;
    646 	mode_t filetype;
    647 	char *p, *q;
    648 
    649 	pathname = pathdup(archive_entry_pathname(e));
    650 	filetype = archive_entry_filetype(e);
    651 
    652 	/* sanity checks */
    653 	if (pathname[0] == '/' ||
    654 	    strncmp(pathname, "../", 3) == 0 ||
    655 	    strstr(pathname, "/../") != NULL) {
    656 		warningx("skipping insecure entry '%s'", pathname);
    657 		ac(archive_read_data_skip(a));
    658 		free(pathname);
    659 		return;
    660 	}
    661 
    662 	/* I don't think this can happen in a zipfile.. */
    663 	if (!S_ISDIR(filetype) && !S_ISREG(filetype)) {
    664 		warningx("skipping non-regular entry '%s'", pathname);
    665 		ac(archive_read_data_skip(a));
    666 		free(pathname);
    667 		return;
    668 	}
    669 
    670 	/* skip directories in -j case */
    671 	if (S_ISDIR(filetype) && j_opt) {
    672 		ac(archive_read_data_skip(a));
    673 		free(pathname);
    674 		return;
    675 	}
    676 
    677 	/* apply include / exclude patterns */
    678 	if (!accept_pathname(pathname)) {
    679 		ac(archive_read_data_skip(a));
    680 		free(pathname);
    681 		return;
    682 	}
    683 
    684 	/* apply -j and -d */
    685 	if (j_opt) {
    686 		for (p = q = pathname; *p; ++p)
    687 			if (*p == '/')
    688 				q = p + 1;
    689 		realpathname = pathcat(d_arg, q);
    690 	} else {
    691 		realpathname = pathcat(d_arg, pathname);
    692 	}
    693 
    694 	/* ensure that parent directory exists */
    695 	make_parent(realpathname);
    696 
    697 	if (S_ISDIR(filetype))
    698 		extract_dir(a, e, realpathname);
    699 	else
    700 		extract_file(a, e, &realpathname);
    701 
    702 	free(realpathname);
    703 	free(pathname);
    704 }
    705 
    706 static void
    707 extract_stdout(struct archive *a, struct archive_entry *e)
    708 {
    709 	char *pathname;
    710 	mode_t filetype;
    711 	int cr, text, warn;
    712 	ssize_t len;
    713 	unsigned char *p, *q, *end;
    714 
    715 	pathname = pathdup(archive_entry_pathname(e));
    716 	filetype = archive_entry_filetype(e);
    717 
    718 	/* I don't think this can happen in a zipfile.. */
    719 	if (!S_ISDIR(filetype) && !S_ISREG(filetype)) {
    720 		warningx("skipping non-regular entry '%s'", pathname);
    721 		ac(archive_read_data_skip(a));
    722 		free(pathname);
    723 		return;
    724 	}
    725 
    726 	/* skip directories in -j case */
    727 	if (S_ISDIR(filetype)) {
    728 		ac(archive_read_data_skip(a));
    729 		free(pathname);
    730 		return;
    731 	}
    732 
    733 	/* apply include / exclude patterns */
    734 	if (!accept_pathname(pathname)) {
    735 		ac(archive_read_data_skip(a));
    736 		free(pathname);
    737 		return;
    738 	}
    739 
    740 	if (c_opt)
    741 		info("x %s\n", pathname);
    742 
    743 	text = a_opt;
    744 	warn = 0;
    745 	cr = 0;
    746 	for (int n = 0; ; n++) {
    747 		len = archive_read_data(a, buffer, sizeof buffer);
    748 
    749 		if (len < 0)
    750 			ac(len);
    751 
    752 		/* left over CR from previous buffer */
    753 		if (a_opt && cr) {
    754 			if (len == 0 || buffer[0] != '\n') {
    755 				if (fwrite("\r", 1, 1, stderr) != 1)
    756 					error("write('%s')", pathname);
    757 			}
    758 			cr = 0;
    759 		}
    760 
    761 		/* EOF */
    762 		if (len == 0)
    763 			break;
    764 		end = buffer + len;
    765 
    766 		/*
    767 		 * Detect whether this is a text file.  The correct way to
    768 		 * do this is to check the least significant bit of the
    769 		 * "internal file attributes" field of the corresponding
    770 		 * file header in the central directory, but libarchive
    771 		 * does not read the central directory, so we have to
    772 		 * guess by looking for non-ASCII characters in the
    773 		 * buffer.  Hopefully we won't guess wrong.  If we do
    774 		 * guess wrong, we print a warning message later.
    775 		 */
    776 		if (a_opt && n == 0) {
    777 			for (p = buffer; p < end; ++p) {
    778 				if (!isascii((unsigned char)*p)) {
    779 					text = 0;
    780 					break;
    781 				}
    782 			}
    783 		}
    784 
    785 		/* simple case */
    786 		if (!a_opt || !text) {
    787 			if (fwrite(buffer, 1, len, stdout) != (size_t)len)
    788 				error("write('%s')", pathname);
    789 			continue;
    790 		}
    791 
    792 		/* hard case: convert \r\n to \n (sigh...) */
    793 		for (p = buffer; p < end; p = q + 1) {
    794 			for (q = p; q < end; q++) {
    795 				if (!warn && !isascii(*q)) {
    796 					warningx("%s may be corrupted due"
    797 					    " to weak text file detection"
    798 					    " heuristic", pathname);
    799 					warn = 1;
    800 				}
    801 				if (q[0] != '\r')
    802 					continue;
    803 				if (&q[1] == end) {
    804 					cr = 1;
    805 					break;
    806 				}
    807 				if (q[1] == '\n')
    808 					break;
    809 			}
    810 			if (fwrite(p, 1, q - p, stdout) != (size_t)(q - p))
    811 				error("write('%s')", pathname);
    812 		}
    813 	}
    814 
    815 	free(pathname);
    816 }
    817 
    818 /*
    819  * Print the name of an entry to stdout.
    820  */
    821 static void
    822 list(struct archive *a, struct archive_entry *e)
    823 {
    824 	char buf[20];
    825 	time_t mtime;
    826 
    827 	mtime = archive_entry_mtime(e);
    828 	strftime(buf, sizeof(buf), "%m-%d-%g %R", localtime(&mtime));
    829 
    830 	if (v_opt == 1) {
    831 		printf(" %8ju  %s   %s\n",
    832 		    (uintmax_t)archive_entry_size(e),
    833 		    buf, archive_entry_pathname(e));
    834 	} else if (v_opt == 2) {
    835 		printf("%8ju  Stored  %7ju   0%%  %s  %08x  %s\n",
    836 		    (uintmax_t)archive_entry_size(e),
    837 		    (uintmax_t)archive_entry_size(e),
    838 		    buf,
    839 		    0U,
    840 		    archive_entry_pathname(e));
    841 	}
    842 	ac(archive_read_data_skip(a));
    843 }
    844 
    845 /*
    846  * Extract to memory to check CRC
    847  */
    848 static int
    849 test(struct archive *a, struct archive_entry *e)
    850 {
    851 	ssize_t len;
    852 	int error_count;
    853 
    854 	error_count = 0;
    855 	if (S_ISDIR(archive_entry_filetype(e)))
    856 		return 0;
    857 
    858 	info("    testing: %s\t", archive_entry_pathname(e));
    859 	while ((len = archive_read_data(a, buffer, sizeof buffer)) > 0)
    860 		/* nothing */;
    861 	if (len < 0) {
    862 		info(" %s\n", archive_error_string(a));
    863 		++error_count;
    864 	} else {
    865 		info(" OK\n");
    866 	}
    867 
    868 	/* shouldn't be necessary, but it doesn't hurt */
    869 	ac(archive_read_data_skip(a));
    870 
    871 	return error_count;
    872 }
    873 
    874 
    875 /*
    876  * Main loop: open the zipfile, iterate over its contents and decide what
    877  * to do with each entry.
    878  */
    879 static void
    880 unzip(const char *fn)
    881 {
    882 	struct archive *a;
    883 	struct archive_entry *e;
    884 	int fd, ret;
    885 	uintmax_t total_size, file_count, error_count;
    886 
    887 	if ((fd = open(fn, O_RDONLY)) < 0)
    888 		error("%s", fn);
    889 
    890 	a = archive_read_new();
    891 	ac(archive_read_support_format_zip(a));
    892 	ac(archive_read_open_fd(a, fd, 8192));
    893 
    894 	if (!q_opt && !p_opt)
    895 	    printf("Archive:  %s\n", fn);
    896 
    897 	if (v_opt == 1) {
    898 		printf("  Length     Date   Time    Name\n");
    899 		printf(" --------    ----   ----    ----\n");
    900 	} else if (v_opt == 2) {
    901 		printf(" Length   Method    Size  Ratio   Date   Time   CRC-32    Name\n");
    902 		printf("--------  ------  ------- -----   ----   ----   ------    ----\n");
    903 	}
    904 
    905 	total_size = 0;
    906 	file_count = 0;
    907 	error_count = 0;
    908 	for (;;) {
    909 		ret = archive_read_next_header(a, &e);
    910 		if (ret == ARCHIVE_EOF)
    911 			break;
    912 		ac(ret);
    913 		if (t_opt)
    914 			error_count += test(a, e);
    915 		else if (v_opt)
    916 			list(a, e);
    917 		else if (p_opt || c_opt)
    918 			extract_stdout(a, e);
    919 		else
    920 			extract(a, e);
    921 
    922 		total_size += archive_entry_size(e);
    923 		++file_count;
    924 	}
    925 
    926 	if (v_opt == 1) {
    927 		printf(" --------                   -------\n");
    928 		printf(" %8ju                   %ju file%s\n",
    929 		    total_size, file_count, file_count != 1 ? "s" : "");
    930 	} else if (v_opt == 2) {
    931 		printf("--------          -------  ---                            -------\n");
    932 		printf("%8ju          %7ju   0%%                            %ju file%s\n",
    933 		    total_size, total_size, file_count,
    934 		    file_count != 1 ? "s" : "");
    935 	}
    936 
    937 	ac(archive_read_close(a));
    938 	(void)archive_read_finish(a);
    939 
    940 	if (close(fd) != 0)
    941 		error("%s", fn);
    942 
    943 	if (t_opt) {
    944 		if (error_count > 0) {
    945 			errorx("%d checksum error(s) found.", error_count);
    946 		}
    947 		else {
    948 			printf("No errors detected in compressed data of %s.\n",
    949 			       fn);
    950 		}
    951 	}
    952 }
    953 
    954 static void
    955 usage(void)
    956 {
    957 
    958 	fprintf(stderr, "usage: unzip [-aCcfjLlnopqtuv] [-d dir] [-x pattern] zipfile\n");
    959 	exit(1);
    960 }
    961 
    962 static int
    963 getopts(int argc, char *argv[])
    964 {
    965 	int opt;
    966 
    967 	optreset = optind = 1;
    968 	while ((opt = getopt(argc, argv, "aCcd:fjLlnopqtuvx:")) != -1)
    969 		switch (opt) {
    970 		case 'a':
    971 			a_opt = 1;
    972 			break;
    973 		case 'C':
    974 			C_opt = 1;
    975 			break;
    976 		case 'c':
    977 			c_opt = 1;
    978 			break;
    979 		case 'd':
    980 			d_arg = optarg;
    981 			break;
    982 		case 'f':
    983 			f_opt = 1;
    984 			break;
    985 		case 'j':
    986 			j_opt = 1;
    987 			break;
    988 		case 'L':
    989 			L_opt = 1;
    990 			break;
    991 		case 'l':
    992 			if (v_opt == 0)
    993 				v_opt = 1;
    994 			break;
    995 		case 'n':
    996 			n_opt = 1;
    997 			break;
    998 		case 'o':
    999 			o_opt = 1;
   1000 			q_opt = 1;
   1001 			break;
   1002 		case 'p':
   1003 			p_opt = 1;
   1004 			break;
   1005 		case 'q':
   1006 			q_opt = 1;
   1007 			break;
   1008 		case 't':
   1009 			t_opt = 1;
   1010 			break;
   1011 		case 'u':
   1012 			u_opt = 1;
   1013 			break;
   1014 		case 'v':
   1015 			v_opt = 2;
   1016 			break;
   1017 		case 'x':
   1018 			add_pattern(&exclude, optarg);
   1019 			break;
   1020 		default:
   1021 			usage();
   1022 		}
   1023 
   1024 	return (optind);
   1025 }
   1026 
   1027 int
   1028 main(int argc, char *argv[])
   1029 {
   1030 	const char *zipfile;
   1031 	int nopts;
   1032 
   1033 	if (isatty(STDOUT_FILENO))
   1034 		tty = 1;
   1035 
   1036 	if (getenv("UNZIP_DEBUG") != NULL)
   1037 		unzip_debug = 1;
   1038 	for (int i = 0; i < argc; ++i)
   1039 		debug("%s%c", argv[i], (i < argc - 1) ? ' ' : '\n');
   1040 
   1041 	/*
   1042 	 * Info-ZIP's unzip(1) expects certain options to come before the
   1043 	 * zipfile name, and others to come after - though it does not
   1044 	 * enforce this.  For simplicity, we accept *all* options both
   1045 	 * before and after the zipfile name.
   1046 	 */
   1047 	nopts = getopts(argc, argv);
   1048 
   1049 	if (argc <= nopts)
   1050 		usage();
   1051 	zipfile = argv[nopts++];
   1052 
   1053 	while (nopts < argc && *argv[nopts] != '-')
   1054 		add_pattern(&include, argv[nopts++]);
   1055 
   1056 	nopts--; /* fake argv[0] */
   1057 	nopts += getopts(argc - nopts, argv + nopts);
   1058 
   1059 	if (n_opt + o_opt + u_opt > 1)
   1060 		errorx("-n, -o and -u are contradictory");
   1061 
   1062 	time(&now);
   1063 
   1064 	unzip(zipfile);
   1065 
   1066 	exit(0);
   1067 }
   1068