1 /*-
2  * Copyright (c) 2003-2007 Tim Kientzle
3  * Copyright (c) 2008 Joerg Sonnenberger
4  * Copyright (c) 2011-2012 Michihiro NAKAJIMA
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(S) ``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(S) BE LIABLE FOR ANY DIRECT, INDIRECT,
20  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26  */
27 
28 #include "archive_platform.h"
29 __FBSDID("$FreeBSD: head/lib/libarchive/archive_read_support_format_mtree.c 201165 2009-12-29 05:52:13Z kientzle $");
30 
31 #ifdef HAVE_SYS_STAT_H
32 #include <sys/stat.h>
33 #endif
34 #ifdef HAVE_ERRNO_H
35 #include <errno.h>
36 #endif
37 #ifdef HAVE_FCNTL_H
38 #include <fcntl.h>
39 #endif
40 #include <stddef.h>
41 /* #include <stdint.h> */ /* See archive_platform.h */
42 #ifdef HAVE_STDLIB_H
43 #include <stdlib.h>
44 #endif
45 #ifdef HAVE_STRING_H
46 #include <string.h>
47 #endif
48 #ifdef HAVE_CTYPE_H
49 #include <ctype.h>
50 #endif
51 
52 #include "archive.h"
53 #include "archive_entry.h"
54 #include "archive_entry_private.h"
55 #include "archive_private.h"
56 #include "archive_rb.h"
57 #include "archive_read_private.h"
58 #include "archive_string.h"
59 #include "archive_pack_dev.h"
60 
61 #ifndef O_BINARY
62 #define	O_BINARY 0
63 #endif
64 #ifndef O_CLOEXEC
65 #define O_CLOEXEC	0
66 #endif
67 
68 #define	MTREE_HAS_DEVICE	0x0001
69 #define	MTREE_HAS_FFLAGS	0x0002
70 #define	MTREE_HAS_GID		0x0004
71 #define	MTREE_HAS_GNAME		0x0008
72 #define	MTREE_HAS_MTIME		0x0010
73 #define	MTREE_HAS_NLINK		0x0020
74 #define	MTREE_HAS_PERM		0x0040
75 #define	MTREE_HAS_SIZE		0x0080
76 #define	MTREE_HAS_TYPE		0x0100
77 #define	MTREE_HAS_UID		0x0200
78 #define	MTREE_HAS_UNAME		0x0400
79 
80 #define	MTREE_HAS_OPTIONAL	0x0800
81 #define	MTREE_HAS_NOCHANGE	0x1000 /* FreeBSD specific */
82 
83 #define	MAX_LINE_LEN		(1024 * 1024)
84 
85 struct mtree_option {
86 	struct mtree_option *next;
87 	char *value;
88 };
89 
90 struct mtree_entry {
91 	struct archive_rb_node rbnode;
92 	struct mtree_entry *next_dup;
93 	struct mtree_entry *next;
94 	struct mtree_option *options;
95 	char *name;
96 	char full;
97 	char used;
98 };
99 
100 struct mtree {
101 	struct archive_string	 line;
102 	size_t			 buffsize;
103 	char			*buff;
104 	int64_t			 offset;
105 	int			 fd;
106 	int			 archive_format;
107 	const char		*archive_format_name;
108 	struct mtree_entry	*entries;
109 	struct mtree_entry	*this_entry;
110 	struct archive_rb_tree	 entry_rbtree;
111 	struct archive_string	 current_dir;
112 	struct archive_string	 contents_name;
113 
114 	struct archive_entry_linkresolver *resolver;
115 	struct archive_rb_tree rbtree;
116 
117 	int64_t			 cur_size;
118 	char checkfs;
119 };
120 
121 static int	bid_keycmp(const char *, const char *, ssize_t);
122 static int	cleanup(struct archive_read *);
123 static int	detect_form(struct archive_read *, int *);
124 static int	mtree_bid(struct archive_read *, int);
125 static int	parse_file(struct archive_read *, struct archive_entry *,
126 		    struct mtree *, struct mtree_entry *, int *);
127 static void	parse_escapes(char *, struct mtree_entry *);
128 static int	parse_line(struct archive_read *, struct archive_entry *,
129 		    struct mtree *, struct mtree_entry *, int *);
130 static int	parse_keyword(struct archive_read *, struct mtree *,
131 		    struct archive_entry *, struct mtree_option *, int *);
132 static int	read_data(struct archive_read *a,
133 		    const void **buff, size_t *size, int64_t *offset);
134 static ssize_t	readline(struct archive_read *, struct mtree *, char **, ssize_t);
135 static int	skip(struct archive_read *a);
136 static int	read_header(struct archive_read *,
137 		    struct archive_entry *);
138 static int64_t	mtree_atol(char **, int base);
139 #ifndef HAVE_STRNLEN
140 static size_t	mtree_strnlen(const char *, size_t);
141 #endif
142 
143 /*
144  * There's no standard for TIME_T_MAX/TIME_T_MIN.  So we compute them
145  * here.  TODO: Move this to configure time, but be careful
146  * about cross-compile environments.
147  */
148 static int64_t
149 get_time_t_max(void)
150 {
151 #if defined(TIME_T_MAX)
152 	return TIME_T_MAX;
153 #else
154 	/* ISO C allows time_t to be a floating-point type,
155 	   but POSIX requires an integer type.  The following
156 	   should work on any system that follows the POSIX
157 	   conventions. */
158 	if (((time_t)0) < ((time_t)-1)) {
159 		/* Time_t is unsigned */
160 		return (~(time_t)0);
161 	} else {
162 		/* Time_t is signed. */
163 		/* Assume it's the same as int64_t or int32_t */
164 		if (sizeof(time_t) == sizeof(int64_t)) {
165 			return (time_t)INT64_MAX;
166 		} else {
167 			return (time_t)INT32_MAX;
168 		}
169 	}
170 #endif
171 }
172 
173 static int64_t
174 get_time_t_min(void)
175 {
176 #if defined(TIME_T_MIN)
177 	return TIME_T_MIN;
178 #else
179 	if (((time_t)0) < ((time_t)-1)) {
180 		/* Time_t is unsigned */
181 		return (time_t)0;
182 	} else {
183 		/* Time_t is signed. */
184 		if (sizeof(time_t) == sizeof(int64_t)) {
185 			return (time_t)INT64_MIN;
186 		} else {
187 			return (time_t)INT32_MIN;
188 		}
189 	}
190 #endif
191 }
192 
193 #ifdef HAVE_STRNLEN
194 #define mtree_strnlen(a,b) strnlen(a,b)
195 #else
196 static size_t
197 mtree_strnlen(const char *p, size_t maxlen)
198 {
199 	size_t i;
200 
201 	for (i = 0; i <= maxlen; i++) {
202 		if (p[i] == 0)
203 			break;
204 	}
205 	if (i > maxlen)
206 		return (-1);/* invalid */
207 	return (i);
208 }
209 #endif
210 
211 static int
212 archive_read_format_mtree_options(struct archive_read *a,
213     const char *key, const char *val)
214 {
215 	struct mtree *mtree;
216 
217 	mtree = (struct mtree *)(a->format->data);
218 	if (strcmp(key, "checkfs")  == 0) {
219 		/* Allows to read information missing from the mtree from the file system */
220 		if (val == NULL || val[0] == 0) {
221 			mtree->checkfs = 0;
222 		} else {
223 			mtree->checkfs = 1;
224 		}
225 		return (ARCHIVE_OK);
226 	}
227 
228 	/* Note: The "warn" return is just to inform the options
229 	 * supervisor that we didn't handle it.  It will generate
230 	 * a suitable error if no one used this option. */
231 	return (ARCHIVE_WARN);
232 }
233 
234 static void
235 free_options(struct mtree_option *head)
236 {
237 	struct mtree_option *next;
238 
239 	for (; head != NULL; head = next) {
240 		next = head->next;
241 		free(head->value);
242 		free(head);
243 	}
244 }
245 
246 static int
247 mtree_cmp_node(const struct archive_rb_node *n1,
248     const struct archive_rb_node *n2)
249 {
250 	const struct mtree_entry *e1 = (const struct mtree_entry *)n1;
251 	const struct mtree_entry *e2 = (const struct mtree_entry *)n2;
252 
253 	return (strcmp(e1->name, e2->name));
254 }
255 
256 static int
257 mtree_cmp_key(const struct archive_rb_node *n, const void *key)
258 {
259 	const struct mtree_entry *e = (const struct mtree_entry *)n;
260 
261 	return (strcmp(e->name, key));
262 }
263 
264 int
265 archive_read_support_format_mtree(struct archive *_a)
266 {
267 	static const struct archive_rb_tree_ops rb_ops = {
268 		mtree_cmp_node, mtree_cmp_key,
269 	};
270 	struct archive_read *a = (struct archive_read *)_a;
271 	struct mtree *mtree;
272 	int r;
273 
274 	archive_check_magic(_a, ARCHIVE_READ_MAGIC,
275 	    ARCHIVE_STATE_NEW, "archive_read_support_format_mtree");
276 
277 	mtree = (struct mtree *)calloc(1, sizeof(*mtree));
278 	if (mtree == NULL) {
279 		archive_set_error(&a->archive, ENOMEM,
280 		    "Can't allocate mtree data");
281 		return (ARCHIVE_FATAL);
282 	}
283 	mtree->checkfs = 0;
284 	mtree->fd = -1;
285 
286 	__archive_rb_tree_init(&mtree->rbtree, &rb_ops);
287 
288 	r = __archive_read_register_format(a, mtree, "mtree",
289            mtree_bid, archive_read_format_mtree_options, read_header, read_data, skip, NULL, cleanup, NULL, NULL);
290 
291 	if (r != ARCHIVE_OK)
292 		free(mtree);
293 	return (ARCHIVE_OK);
294 }
295 
296 static int
297 cleanup(struct archive_read *a)
298 {
299 	struct mtree *mtree;
300 	struct mtree_entry *p, *q;
301 
302 	mtree = (struct mtree *)(a->format->data);
303 
304 	p = mtree->entries;
305 	while (p != NULL) {
306 		q = p->next;
307 		free(p->name);
308 		free_options(p->options);
309 		free(p);
310 		p = q;
311 	}
312 	archive_string_free(&mtree->line);
313 	archive_string_free(&mtree->current_dir);
314 	archive_string_free(&mtree->contents_name);
315 	archive_entry_linkresolver_free(mtree->resolver);
316 
317 	free(mtree->buff);
318 	free(mtree);
319 	(a->format->data) = NULL;
320 	return (ARCHIVE_OK);
321 }
322 
323 static ssize_t
324 get_line_size(const char *b, ssize_t avail, ssize_t *nlsize)
325 {
326 	ssize_t len;
327 
328 	len = 0;
329 	while (len < avail) {
330 		switch (*b) {
331 		case '\0':/* Non-ascii character or control character. */
332 			if (nlsize != NULL)
333 				*nlsize = 0;
334 			return (-1);
335 		case '\r':
336 			if (avail-len > 1 && b[1] == '\n') {
337 				if (nlsize != NULL)
338 					*nlsize = 2;
339 				return (len+2);
340 			}
341 			/* FALL THROUGH */
342 		case '\n':
343 			if (nlsize != NULL)
344 				*nlsize = 1;
345 			return (len+1);
346 		default:
347 			b++;
348 			len++;
349 			break;
350 		}
351 	}
352 	if (nlsize != NULL)
353 		*nlsize = 0;
354 	return (avail);
355 }
356 
357 /*
358  *  <---------------- ravail --------------------->
359  *  <-- diff ------> <---  avail ----------------->
360  *                   <---- len ----------->
361  * | Previous lines | line being parsed  nl extra |
362  *                  ^
363  *                  b
364  *
365  */
366 static ssize_t
367 next_line(struct archive_read *a,
368     const char **b, ssize_t *avail, ssize_t *ravail, ssize_t *nl)
369 {
370 	ssize_t len;
371 	int quit;
372 
373 	quit = 0;
374 	if (*avail == 0) {
375 		*nl = 0;
376 		len = 0;
377 	} else
378 		len = get_line_size(*b, *avail, nl);
379 	/*
380 	 * Read bytes more while it does not reach the end of line.
381 	 */
382 	while (*nl == 0 && len == *avail && !quit) {
383 		ssize_t diff = *ravail - *avail;
384 		size_t nbytes_req = (*ravail+1023) & ~1023U;
385 		ssize_t tested;
386 
387 		/*
388 		 * Place an arbitrary limit on the line length.
389 		 * mtree is almost free-form input and without line length limits,
390 		 * it can consume a lot of memory.
391 		 */
392 		if (len >= MAX_LINE_LEN)
393 			return (-1);
394 
395 		/* Increase reading bytes if it is not enough to at least
396 		 * new two lines. */
397 		if (nbytes_req < (size_t)*ravail + 160)
398 			nbytes_req <<= 1;
399 
400 		*b = __archive_read_ahead(a, nbytes_req, avail);
401 		if (*b == NULL) {
402 			if (*ravail >= *avail)
403 				return (0);
404 			/* Reading bytes reaches the end of file. */
405 			*b = __archive_read_ahead(a, *avail, avail);
406 			quit = 1;
407 		}
408 		*ravail = *avail;
409 		*b += diff;
410 		*avail -= diff;
411 		tested = len;/* Skip some bytes we already determined. */
412 		len = get_line_size(*b + len, *avail - len, nl);
413 		if (len >= 0)
414 			len += tested;
415 	}
416 	return (len);
417 }
418 
419 /*
420  * Compare characters with a mtree keyword.
421  * Returns the length of a mtree keyword if matched.
422  * Returns 0 if not matched.
423  */
424 static int
425 bid_keycmp(const char *p, const char *key, ssize_t len)
426 {
427 	int match_len = 0;
428 
429 	while (len > 0 && *p && *key) {
430 		if (*p == *key) {
431 			--len;
432 			++p;
433 			++key;
434 			++match_len;
435 			continue;
436 		}
437 		return (0);/* Not match */
438 	}
439 	if (*key != '\0')
440 		return (0);/* Not match */
441 
442 	/* A following character should be specified characters */
443 	if (p[0] == '=' || p[0] == ' ' || p[0] == '\t' ||
444 	    p[0] == '\n' || p[0] == '\r' ||
445 	   (p[0] == '\\' && (p[1] == '\n' || p[1] == '\r')))
446 		return (match_len);
447 	return (0);/* Not match */
448 }
449 
450 /*
451  * Test whether the characters 'p' has is mtree keyword.
452  * Returns the length of a detected keyword.
453  * Returns 0 if any keywords were not found.
454  */
455 static int
456 bid_keyword(const char *p,  ssize_t len)
457 {
458 	static const char * const keys_c[] = {
459 		"content", "contents", "cksum", NULL
460 	};
461 	static const char * const keys_df[] = {
462 		"device", "flags", NULL
463 	};
464 	static const char * const keys_g[] = {
465 		"gid", "gname", NULL
466 	};
467 	static const char * const keys_il[] = {
468 		"ignore", "inode", "link", NULL
469 	};
470 	static const char * const keys_m[] = {
471 		"md5", "md5digest", "mode", NULL
472 	};
473 	static const char * const keys_no[] = {
474 		"nlink", "nochange", "optional", NULL
475 	};
476 	static const char * const keys_r[] = {
477 		"resdevice", "rmd160", "rmd160digest", NULL
478 	};
479 	static const char * const keys_s[] = {
480 		"sha1", "sha1digest",
481 		"sha256", "sha256digest",
482 		"sha384", "sha384digest",
483 		"sha512", "sha512digest",
484 		"size", NULL
485 	};
486 	static const char * const keys_t[] = {
487 		"tags", "time", "type", NULL
488 	};
489 	static const char * const keys_u[] = {
490 		"uid", "uname",	NULL
491 	};
492 	const char * const *keys;
493 	int i;
494 
495 	switch (*p) {
496 	case 'c': keys = keys_c; break;
497 	case 'd': case 'f': keys = keys_df; break;
498 	case 'g': keys = keys_g; break;
499 	case 'i': case 'l': keys = keys_il; break;
500 	case 'm': keys = keys_m; break;
501 	case 'n': case 'o': keys = keys_no; break;
502 	case 'r': keys = keys_r; break;
503 	case 's': keys = keys_s; break;
504 	case 't': keys = keys_t; break;
505 	case 'u': keys = keys_u; break;
506 	default: return (0);/* Unknown key */
507 	}
508 
509 	for (i = 0; keys[i] != NULL; i++) {
510 		int l = bid_keycmp(p, keys[i], len);
511 		if (l > 0)
512 			return (l);
513 	}
514 	return (0);/* Unknown key */
515 }
516 
517 /*
518  * Test whether there is a set of mtree keywords.
519  * Returns the number of keyword.
520  * Returns -1 if we got incorrect sequence.
521  * This function expects a set of "<space characters>keyword=value".
522  * When "unset" is specified, expects a set of "<space characters>keyword".
523  */
524 static int
525 bid_keyword_list(const char *p,  ssize_t len, int unset, int last_is_path)
526 {
527 	int l;
528 	int keycnt = 0;
529 
530 	while (len > 0 && *p) {
531 		int blank = 0;
532 
533 		/* Test whether there are blank characters in the line. */
534 		while (len >0 && (*p == ' ' || *p == '\t')) {
535 			++p;
536 			--len;
537 			blank = 1;
538 		}
539 		if (*p == '\n' || *p == '\r')
540 			break;
541 		if (p[0] == '\\' && (p[1] == '\n' || p[1] == '\r'))
542 			break;
543 		if (!blank && !last_is_path) /* No blank character. */
544 			return (-1);
545 		if (last_is_path && len == 0)
546 				return (keycnt);
547 
548 		if (unset) {
549 			l = bid_keycmp(p, "all", len);
550 			if (l > 0)
551 				return (1);
552 		}
553 		/* Test whether there is a correct key in the line. */
554 		l = bid_keyword(p, len);
555 		if (l == 0)
556 			return (-1);/* Unknown keyword was found. */
557 		p += l;
558 		len -= l;
559 		keycnt++;
560 
561 		/* Skip value */
562 		if (*p == '=') {
563 			int value = 0;
564 			++p;
565 			--len;
566 			while (len > 0 && *p != ' ' && *p != '\t') {
567 				++p;
568 				--len;
569 				value = 1;
570 			}
571 			/* A keyword should have a its value unless
572 			 * "/unset" operation. */
573 			if (!unset && value == 0)
574 				return (-1);
575 		}
576 	}
577 	return (keycnt);
578 }
579 
580 static int
581 bid_entry(const char *p, ssize_t len, ssize_t nl, int *last_is_path)
582 {
583 	int f = 0;
584 	static const unsigned char safe_char[256] = {
585 		0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* 00 - 0F */
586 		0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* 10 - 1F */
587 		/* !"$%&'()*+,-./  EXCLUSION:( )(#) */
588 		0, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, /* 20 - 2F */
589 		/* 0123456789:;<>?  EXCLUSION:(=) */
590 		1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, /* 30 - 3F */
591 		/* @ABCDEFGHIJKLMNO */
592 		1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, /* 40 - 4F */
593 		/* PQRSTUVWXYZ[\]^_  */
594 		1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, /* 50 - 5F */
595 		/* `abcdefghijklmno */
596 		1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, /* 60 - 6F */
597 		/* pqrstuvwxyz{|}~ */
598 		1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, /* 70 - 7F */
599 		0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* 80 - 8F */
600 		0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* 90 - 9F */
601 		0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* A0 - AF */
602 		0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* B0 - BF */
603 		0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* C0 - CF */
604 		0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* D0 - DF */
605 		0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* E0 - EF */
606 		0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* F0 - FF */
607 	};
608 	ssize_t ll;
609 	const char *pp = p;
610 	const char * const pp_end = pp + len;
611 
612 	*last_is_path = 0;
613 	/*
614 	 * Skip the path-name which is quoted.
615 	 */
616 	for (;pp < pp_end; ++pp) {
617 		if (!safe_char[*(const unsigned char *)pp]) {
618 			if (*pp != ' ' && *pp != '\t' && *pp != '\r'
619 			    && *pp != '\n')
620 				f = 0;
621 			break;
622 		}
623 		f = 1;
624 	}
625 	ll = pp_end - pp;
626 
627 	/* If a path-name was not found at the first, try to check
628 	 * a mtree format(a.k.a form D) ``NetBSD's mtree -D'' creates,
629 	 * which places the path-name at the last. */
630 	if (f == 0) {
631 		const char *pb = p + len - nl;
632 		int name_len = 0;
633 		int slash;
634 
635 		/* The form D accepts only a single line for an entry. */
636 		if (pb-2 >= p &&
637 		    pb[-1] == '\\' && (pb[-2] == ' ' || pb[-2] == '\t'))
638 			return (-1);
639 		if (pb-1 >= p && pb[-1] == '\\')
640 			return (-1);
641 
642 		slash = 0;
643 		while (p <= --pb && *pb != ' ' && *pb != '\t') {
644 			if (!safe_char[*(const unsigned char *)pb])
645 				return (-1);
646 			name_len++;
647 			/* The pathname should have a slash in this
648 			 * format. */
649 			if (*pb == '/')
650 				slash = 1;
651 		}
652 		if (name_len == 0 || slash == 0)
653 			return (-1);
654 		/* If '/' is placed at the first in this field, this is not
655 		 * a valid filename. */
656 		if (pb[1] == '/')
657 			return (-1);
658 		ll = len - nl - name_len;
659 		pp = p;
660 		*last_is_path = 1;
661 	}
662 
663 	return (bid_keyword_list(pp, ll, 0, *last_is_path));
664 }
665 
666 #define MAX_BID_ENTRY	3
667 
668 static int
669 mtree_bid(struct archive_read *a, int best_bid)
670 {
671 	const char *signature = "#mtree";
672 	const char *p;
673 
674 	(void)best_bid; /* UNUSED */
675 
676 	/* Now let's look at the actual header and see if it matches. */
677 	p = __archive_read_ahead(a, strlen(signature), NULL);
678 	if (p == NULL)
679 		return (-1);
680 
681 	if (memcmp(p, signature, strlen(signature)) == 0)
682 		return (8 * (int)strlen(signature));
683 
684 	/*
685 	 * There is not a mtree signature. Let's try to detect mtree format.
686 	 */
687 	return (detect_form(a, NULL));
688 }
689 
690 static int
691 detect_form(struct archive_read *a, int *is_form_d)
692 {
693 	const char *p;
694 	ssize_t avail, ravail;
695 	ssize_t len, nl;
696 	int entry_cnt = 0, multiline = 0;
697 	int form_D = 0;/* The archive is generated by `NetBSD mtree -D'
698 			* (In this source we call it `form D') . */
699 
700 	if (is_form_d != NULL)
701 		*is_form_d = 0;
702 	p = __archive_read_ahead(a, 1, &avail);
703 	if (p == NULL)
704 		return (-1);
705 	ravail = avail;
706 	for (;;) {
707 		len = next_line(a, &p, &avail, &ravail, &nl);
708 		/* The terminal character of the line should be
709 		 * a new line character, '\r\n' or '\n'. */
710 		if (len <= 0 || nl == 0)
711 			break;
712 		if (!multiline) {
713 			/* Leading whitespace is never significant,
714 			 * ignore it. */
715 			while (len > 0 && (*p == ' ' || *p == '\t')) {
716 				++p;
717 				--avail;
718 				--len;
719 			}
720 			/* Skip comment or empty line. */
721 			if (p[0] == '#' || p[0] == '\n' || p[0] == '\r') {
722 				p += len;
723 				avail -= len;
724 				continue;
725 			}
726 		} else {
727 			/* A continuance line; the terminal
728 			 * character of previous line was '\' character. */
729 			if (bid_keyword_list(p, len, 0, 0) <= 0)
730 				break;
731 			if (p[len-nl-1] != '\\') {
732 				if (multiline == 1 &&
733 				    ++entry_cnt >= MAX_BID_ENTRY)
734 					break;
735 				multiline = 0;
736 			}
737 			p += len;
738 			avail -= len;
739 			continue;
740 		}
741 		if (p[0] != '/') {
742 			int last_is_path, keywords;
743 
744 			keywords = bid_entry(p, len, nl, &last_is_path);
745 			if (keywords >= 0) {
746 				if (form_D == 0) {
747 					if (last_is_path)
748 						form_D = 1;
749 					else if (keywords > 0)
750 						/* This line is not `form D'. */
751 						form_D = -1;
752 				} else if (form_D == 1) {
753 					if (!last_is_path && keywords > 0)
754 						/* This this is not `form D'
755 						 * and We cannot accept mixed
756 						 * format. */
757 						break;
758 				}
759 				if (!last_is_path && p[len-nl-1] == '\\')
760 					/* This line continues. */
761 					multiline = 1;
762 				else {
763 					/* We've got plenty of correct lines
764 					 * to assume that this file is a mtree
765 					 * format. */
766 					if (++entry_cnt >= MAX_BID_ENTRY)
767 						break;
768 				}
769 			} else
770 				break;
771 		} else if (len > 4 && strncmp(p, "/set", 4) == 0) {
772 			if (bid_keyword_list(p+4, len-4, 0, 0) <= 0)
773 				break;
774 			/* This line continues. */
775 			if (p[len-nl-1] == '\\')
776 				multiline = 2;
777 		} else if (len > 6 && strncmp(p, "/unset", 6) == 0) {
778 			if (bid_keyword_list(p+6, len-6, 1, 0) <= 0)
779 				break;
780 			/* This line continues. */
781 			if (p[len-nl-1] == '\\')
782 				multiline = 2;
783 		} else
784 			break;
785 
786 		/* Test next line. */
787 		p += len;
788 		avail -= len;
789 	}
790 	if (entry_cnt >= MAX_BID_ENTRY || (entry_cnt > 0 && len == 0)) {
791 		if (is_form_d != NULL) {
792 			if (form_D == 1)
793 				*is_form_d = 1;
794 		}
795 		return (32);
796 	}
797 
798 	return (0);
799 }
800 
801 /*
802  * The extended mtree format permits multiple lines specifying
803  * attributes for each file.  For those entries, only the last line
804  * is actually used.  Practically speaking, that means we have
805  * to read the entire mtree file into memory up front.
806  *
807  * The parsing is done in two steps.  First, it is decided if a line
808  * changes the global defaults and if it is, processed accordingly.
809  * Otherwise, the options of the line are merged with the current
810  * global options.
811  */
812 static int
813 add_option(struct archive_read *a, struct mtree_option **global,
814     const char *value, size_t len)
815 {
816 	struct mtree_option *opt;
817 
818 	if ((opt = malloc(sizeof(*opt))) == NULL) {
819 		archive_set_error(&a->archive, errno, "Can't allocate memory");
820 		return (ARCHIVE_FATAL);
821 	}
822 	if ((opt->value = malloc(len + 1)) == NULL) {
823 		free(opt);
824 		archive_set_error(&a->archive, errno, "Can't allocate memory");
825 		return (ARCHIVE_FATAL);
826 	}
827 	memcpy(opt->value, value, len);
828 	opt->value[len] = '\0';
829 	opt->next = *global;
830 	*global = opt;
831 	return (ARCHIVE_OK);
832 }
833 
834 static void
835 remove_option(struct mtree_option **global, const char *value, size_t len)
836 {
837 	struct mtree_option *iter, *last;
838 
839 	last = NULL;
840 	for (iter = *global; iter != NULL; last = iter, iter = iter->next) {
841 		if (strncmp(iter->value, value, len) == 0 &&
842 		    (iter->value[len] == '\0' ||
843 		     iter->value[len] == '='))
844 			break;
845 	}
846 	if (iter == NULL)
847 		return;
848 	if (last == NULL)
849 		*global = iter->next;
850 	else
851 		last->next = iter->next;
852 
853 	free(iter->value);
854 	free(iter);
855 }
856 
857 static int
858 process_global_set(struct archive_read *a,
859     struct mtree_option **global, const char *line)
860 {
861 	const char *next, *eq;
862 	size_t len;
863 	int r;
864 
865 	line += 4;
866 	for (;;) {
867 		next = line + strspn(line, " \t\r\n");
868 		if (*next == '\0')
869 			return (ARCHIVE_OK);
870 		line = next;
871 		next = line + strcspn(line, " \t\r\n");
872 		eq = strchr(line, '=');
873 		if (eq > next)
874 			len = next - line;
875 		else
876 			len = eq - line;
877 
878 		remove_option(global, line, len);
879 		r = add_option(a, global, line, next - line);
880 		if (r != ARCHIVE_OK)
881 			return (r);
882 		line = next;
883 	}
884 }
885 
886 static int
887 process_global_unset(struct archive_read *a,
888     struct mtree_option **global, const char *line)
889 {
890 	const char *next;
891 	size_t len;
892 
893 	line += 6;
894 	if (strchr(line, '=') != NULL) {
895 		archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
896 		    "/unset shall not contain `='");
897 		return ARCHIVE_FATAL;
898 	}
899 
900 	for (;;) {
901 		next = line + strspn(line, " \t\r\n");
902 		if (*next == '\0')
903 			return (ARCHIVE_OK);
904 		line = next;
905 		len = strcspn(line, " \t\r\n");
906 
907 		if (len == 3 && strncmp(line, "all", 3) == 0) {
908 			free_options(*global);
909 			*global = NULL;
910 		} else {
911 			remove_option(global, line, len);
912 		}
913 
914 		line += len;
915 	}
916 }
917 
918 static int
919 process_add_entry(struct archive_read *a, struct mtree *mtree,
920     struct mtree_option **global, const char *line, ssize_t line_len,
921     struct mtree_entry **last_entry, int is_form_d)
922 {
923 	struct mtree_entry *entry;
924 	struct mtree_option *iter;
925 	const char *next, *eq, *name, *end;
926 	size_t name_len, len;
927 	int r, i;
928 
929 	if ((entry = malloc(sizeof(*entry))) == NULL) {
930 		archive_set_error(&a->archive, errno, "Can't allocate memory");
931 		return (ARCHIVE_FATAL);
932 	}
933 	entry->next = NULL;
934 	entry->options = NULL;
935 	entry->name = NULL;
936 	entry->used = 0;
937 	entry->full = 0;
938 
939 	/* Add this entry to list. */
940 	if (*last_entry == NULL)
941 		mtree->entries = entry;
942 	else
943 		(*last_entry)->next = entry;
944 	*last_entry = entry;
945 
946 	if (is_form_d) {
947 		/* Filename is last item on line. */
948 		/* Adjust line_len to trim trailing whitespace */
949 		while (line_len > 0) {
950 			char last_character = line[line_len - 1];
951 			if (last_character == '\r'
952 			    || last_character == '\n'
953 			    || last_character == '\t'
954 			    || last_character == ' ') {
955 				line_len--;
956 			} else {
957 				break;
958 			}
959 		}
960 		/* Name starts after the last whitespace separator */
961 		name = line;
962 		for (i = 0; i < line_len; i++) {
963 			if (line[i] == '\r'
964 			    || line[i] == '\n'
965 			    || line[i] == '\t'
966 			    || line[i] == ' ') {
967 				name = line + i + 1;
968 			}
969 		}
970 		name_len = line + line_len - name;
971 		end = name;
972 	} else {
973 		/* Filename is first item on line */
974 		name_len = strcspn(line, " \t\r\n");
975 		name = line;
976 		line += name_len;
977 		end = line + line_len;
978 	}
979 	/* name/name_len is the name within the line. */
980 	/* line..end brackets the entire line except the name */
981 
982 	if ((entry->name = malloc(name_len + 1)) == NULL) {
983 		archive_set_error(&a->archive, errno, "Can't allocate memory");
984 		return (ARCHIVE_FATAL);
985 	}
986 
987 	memcpy(entry->name, name, name_len);
988 	entry->name[name_len] = '\0';
989 	parse_escapes(entry->name, entry);
990 
991 	entry->next_dup = NULL;
992 	if (entry->full) {
993 		if (!__archive_rb_tree_insert_node(&mtree->rbtree, &entry->rbnode)) {
994 			struct mtree_entry *alt;
995 			alt = (struct mtree_entry *)__archive_rb_tree_find_node(
996 			    &mtree->rbtree, entry->name);
997 			while (alt->next_dup)
998 				alt = alt->next_dup;
999 			alt->next_dup = entry;
1000 		}
1001 	}
1002 
1003 	for (iter = *global; iter != NULL; iter = iter->next) {
1004 		r = add_option(a, &entry->options, iter->value,
1005 		    strlen(iter->value));
1006 		if (r != ARCHIVE_OK)
1007 			return (r);
1008 	}
1009 
1010 	for (;;) {
1011 		next = line + strspn(line, " \t\r\n");
1012 		if (*next == '\0')
1013 			return (ARCHIVE_OK);
1014 		if (next >= end)
1015 			return (ARCHIVE_OK);
1016 		line = next;
1017 		next = line + strcspn(line, " \t\r\n");
1018 		eq = strchr(line, '=');
1019 		if (eq == NULL || eq > next)
1020 			len = next - line;
1021 		else
1022 			len = eq - line;
1023 
1024 		remove_option(&entry->options, line, len);
1025 		r = add_option(a, &entry->options, line, next - line);
1026 		if (r != ARCHIVE_OK)
1027 			return (r);
1028 		line = next;
1029 	}
1030 }
1031 
1032 static int
1033 read_mtree(struct archive_read *a, struct mtree *mtree)
1034 {
1035 	ssize_t len;
1036 	uintmax_t counter;
1037 	char *p, *s;
1038 	struct mtree_option *global;
1039 	struct mtree_entry *last_entry;
1040 	int r, is_form_d;
1041 
1042 	mtree->archive_format = ARCHIVE_FORMAT_MTREE;
1043 	mtree->archive_format_name = "mtree";
1044 
1045 	global = NULL;
1046 	last_entry = NULL;
1047 
1048 	(void)detect_form(a, &is_form_d);
1049 
1050 	for (counter = 1; ; ++counter) {
1051 		r = ARCHIVE_OK;
1052 		len = readline(a, mtree, &p, 65536);
1053 		if (len == 0) {
1054 			mtree->this_entry = mtree->entries;
1055 			free_options(global);
1056 			return (ARCHIVE_OK);
1057 		}
1058 		if (len < 0) {
1059 			free_options(global);
1060 			return ((int)len);
1061 		}
1062 		/* Leading whitespace is never significant, ignore it. */
1063 		while (*p == ' ' || *p == '\t') {
1064 			++p;
1065 			--len;
1066 		}
1067 		/* Skip content lines and blank lines. */
1068 		if (*p == '#')
1069 			continue;
1070 		if (*p == '\r' || *p == '\n' || *p == '\0')
1071 			continue;
1072 		/* Non-printable characters are not allowed */
1073 		for (s = p;s < p + len - 1; s++) {
1074 			if (!isprint((unsigned char)*s)) {
1075 				r = ARCHIVE_FATAL;
1076 				break;
1077 			}
1078 		}
1079 		if (r != ARCHIVE_OK)
1080 			break;
1081 		if (*p != '/') {
1082 			r = process_add_entry(a, mtree, &global, p, len,
1083 			    &last_entry, is_form_d);
1084 		} else if (len > 4 && strncmp(p, "/set", 4) == 0) {
1085 			if (p[4] != ' ' && p[4] != '\t')
1086 				break;
1087 			r = process_global_set(a, &global, p);
1088 		} else if (len > 6 && strncmp(p, "/unset", 6) == 0) {
1089 			if (p[6] != ' ' && p[6] != '\t')
1090 				break;
1091 			r = process_global_unset(a, &global, p);
1092 		} else
1093 			break;
1094 
1095 		if (r != ARCHIVE_OK) {
1096 			free_options(global);
1097 			return r;
1098 		}
1099 	}
1100 
1101 	archive_set_error(&a->archive, ARCHIVE_ERRNO_FILE_FORMAT,
1102 	    "Can't parse line %ju", counter);
1103 	free_options(global);
1104 	return (ARCHIVE_FATAL);
1105 }
1106 
1107 /*
1108  * Read in the entire mtree file into memory on the first request.
1109  * Then use the next unused file to satisfy each header request.
1110  */
1111 static int
1112 read_header(struct archive_read *a, struct archive_entry *entry)
1113 {
1114 	struct mtree *mtree;
1115 	char *p;
1116 	int r, use_next;
1117 
1118 	mtree = (struct mtree *)(a->format->data);
1119 
1120 	if (mtree->fd >= 0) {
1121 		close(mtree->fd);
1122 		mtree->fd = -1;
1123 	}
1124 
1125 	if (mtree->entries == NULL) {
1126 		mtree->resolver = archive_entry_linkresolver_new();
1127 		if (mtree->resolver == NULL)
1128 			return ARCHIVE_FATAL;
1129 		archive_entry_linkresolver_set_strategy(mtree->resolver,
1130 		    ARCHIVE_FORMAT_MTREE);
1131 		r = read_mtree(a, mtree);
1132 		if (r != ARCHIVE_OK)
1133 			return (r);
1134 	}
1135 
1136 	a->archive.archive_format = mtree->archive_format;
1137 	a->archive.archive_format_name = mtree->archive_format_name;
1138 
1139 	for (;;) {
1140 		if (mtree->this_entry == NULL)
1141 			return (ARCHIVE_EOF);
1142 		if (strcmp(mtree->this_entry->name, "..") == 0) {
1143 			mtree->this_entry->used = 1;
1144 			if (archive_strlen(&mtree->current_dir) > 0) {
1145 				/* Roll back current path. */
1146 				p = mtree->current_dir.s
1147 				    + mtree->current_dir.length - 1;
1148 				while (p >= mtree->current_dir.s && *p != '/')
1149 					--p;
1150 				if (p >= mtree->current_dir.s)
1151 					--p;
1152 				mtree->current_dir.length
1153 				    = p - mtree->current_dir.s + 1;
1154 			}
1155 		}
1156 		if (!mtree->this_entry->used) {
1157 			use_next = 0;
1158 			r = parse_file(a, entry, mtree, mtree->this_entry,
1159 				&use_next);
1160 			if (use_next == 0)
1161 				return (r);
1162 		}
1163 		mtree->this_entry = mtree->this_entry->next;
1164 	}
1165 }
1166 
1167 /*
1168  * A single file can have multiple lines contribute specifications.
1169  * Parse as many lines as necessary, then pull additional information
1170  * from a backing file on disk as necessary.
1171  */
1172 static int
1173 parse_file(struct archive_read *a, struct archive_entry *entry,
1174     struct mtree *mtree, struct mtree_entry *mentry, int *use_next)
1175 {
1176 	const char *path;
1177 	struct stat st_storage, *st;
1178 	struct mtree_entry *mp;
1179 	struct archive_entry *sparse_entry;
1180 	int r = ARCHIVE_OK, r1, parsed_kws;
1181 
1182 	mentry->used = 1;
1183 
1184 	/* Initialize reasonable defaults. */
1185 	archive_entry_set_filetype(entry, AE_IFREG);
1186 	archive_entry_set_size(entry, 0);
1187 	archive_string_empty(&mtree->contents_name);
1188 
1189 	/* Parse options from this line. */
1190 	parsed_kws = 0;
1191 	r = parse_line(a, entry, mtree, mentry, &parsed_kws);
1192 
1193 	if (mentry->full) {
1194 		archive_entry_copy_pathname(entry, mentry->name);
1195 		/*
1196 		 * "Full" entries are allowed to have multiple lines
1197 		 * and those lines aren't required to be adjacent.  We
1198 		 * don't support multiple lines for "relative" entries
1199 		 * nor do we make any attempt to merge data from
1200 		 * separate "relative" and "full" entries.  (Merging
1201 		 * "relative" and "full" entries would require dealing
1202 		 * with pathname canonicalization, which is a very
1203 		 * tricky subject.)
1204 		 */
1205 		mp = (struct mtree_entry *)__archive_rb_tree_find_node(
1206 		    &mtree->rbtree, mentry->name);
1207 		for (; mp; mp = mp->next_dup) {
1208 			if (mp->full && !mp->used) {
1209 				/* Later lines override earlier ones. */
1210 				mp->used = 1;
1211 				r1 = parse_line(a, entry, mtree, mp, &parsed_kws);
1212 				if (r1 < r)
1213 					r = r1;
1214 			}
1215 		}
1216 	} else {
1217 		/*
1218 		 * Relative entries require us to construct
1219 		 * the full path and possibly update the
1220 		 * current directory.
1221 		 */
1222 		size_t n = archive_strlen(&mtree->current_dir);
1223 		if (n > 0)
1224 			archive_strcat(&mtree->current_dir, "/");
1225 		archive_strcat(&mtree->current_dir, mentry->name);
1226 		archive_entry_copy_pathname(entry, mtree->current_dir.s);
1227 		if (archive_entry_filetype(entry) != AE_IFDIR)
1228 			mtree->current_dir.length = n;
1229 	}
1230 
1231 	if (mtree->checkfs) {
1232 		/*
1233 		 * Try to open and stat the file to get the real size
1234 		 * and other file info.  It would be nice to avoid
1235 		 * this here so that getting a listing of an mtree
1236 		 * wouldn't require opening every referenced contents
1237 		 * file.  But then we wouldn't know the actual
1238 		 * contents size, so I don't see a really viable way
1239 		 * around this.  (Also, we may want to someday pull
1240 		 * other unspecified info from the contents file on
1241 		 * disk.)
1242 		 */
1243 		mtree->fd = -1;
1244 		if (archive_strlen(&mtree->contents_name) > 0)
1245 			path = mtree->contents_name.s;
1246 		else
1247 			path = archive_entry_pathname(entry);
1248 
1249 		if (archive_entry_filetype(entry) == AE_IFREG ||
1250 				archive_entry_filetype(entry) == AE_IFDIR) {
1251 			mtree->fd = open(path, O_RDONLY | O_BINARY | O_CLOEXEC);
1252 			__archive_ensure_cloexec_flag(mtree->fd);
1253 			if (mtree->fd == -1 &&
1254 				(errno != ENOENT ||
1255 				 archive_strlen(&mtree->contents_name) > 0)) {
1256 				archive_set_error(&a->archive, errno,
1257 						"Can't open %s", path);
1258 				r = ARCHIVE_WARN;
1259 			}
1260 		}
1261 
1262 		st = &st_storage;
1263 		if (mtree->fd >= 0) {
1264 			if (fstat(mtree->fd, st) == -1) {
1265 				archive_set_error(&a->archive, errno,
1266 						"Could not fstat %s", path);
1267 				r = ARCHIVE_WARN;
1268 				/* If we can't stat it, don't keep it open. */
1269 				close(mtree->fd);
1270 				mtree->fd = -1;
1271 				st = NULL;
1272 			}
1273 		} else if (lstat(path, st) == -1) {
1274 			st = NULL;
1275 		}
1276 
1277 		/*
1278 		 * Check for a mismatch between the type in the specification
1279 		 * and the type of the contents object on disk.
1280 		 */
1281 		if (st != NULL) {
1282 			if (((st->st_mode & S_IFMT) == S_IFREG &&
1283 			      archive_entry_filetype(entry) == AE_IFREG)
1284 #ifdef S_IFLNK
1285 			  ||((st->st_mode & S_IFMT) == S_IFLNK &&
1286 			      archive_entry_filetype(entry) == AE_IFLNK)
1287 #endif
1288 #ifdef S_IFSOCK
1289 			  ||((st->st_mode & S_IFSOCK) == S_IFSOCK &&
1290 			      archive_entry_filetype(entry) == AE_IFSOCK)
1291 #endif
1292 #ifdef S_IFCHR
1293 			  ||((st->st_mode & S_IFMT) == S_IFCHR &&
1294 			      archive_entry_filetype(entry) == AE_IFCHR)
1295 #endif
1296 #ifdef S_IFBLK
1297 			  ||((st->st_mode & S_IFMT) == S_IFBLK &&
1298 			      archive_entry_filetype(entry) == AE_IFBLK)
1299 #endif
1300 			  ||((st->st_mode & S_IFMT) == S_IFDIR &&
1301 			      archive_entry_filetype(entry) == AE_IFDIR)
1302 #ifdef S_IFIFO
1303 			  ||((st->st_mode & S_IFMT) == S_IFIFO &&
1304 			      archive_entry_filetype(entry) == AE_IFIFO)
1305 #endif
1306 			) {
1307 				/* Types match. */
1308 			} else {
1309 				/* Types don't match; bail out gracefully. */
1310 				if (mtree->fd >= 0)
1311 					close(mtree->fd);
1312 				mtree->fd = -1;
1313 				if (parsed_kws & MTREE_HAS_OPTIONAL) {
1314 					/* It's not an error for an optional
1315 					 * entry to not match disk. */
1316 					*use_next = 1;
1317 				} else if (r == ARCHIVE_OK) {
1318 					archive_set_error(&a->archive,
1319 					    ARCHIVE_ERRNO_MISC,
1320 					    "mtree specification has different"
1321 					    " type for %s",
1322 					    archive_entry_pathname(entry));
1323 					r = ARCHIVE_WARN;
1324 				}
1325 				return (r);
1326 			}
1327 		}
1328 
1329 		/*
1330 		 * If there is a contents file on disk, pick some of the
1331 		 * metadata from that file.  For most of these, we only
1332 		 * set it from the contents if it wasn't already parsed
1333 		 * from the specification.
1334 		 */
1335 		if (st != NULL) {
1336 			if (((parsed_kws & MTREE_HAS_DEVICE) == 0 ||
1337 				(parsed_kws & MTREE_HAS_NOCHANGE) != 0) &&
1338 				(archive_entry_filetype(entry) == AE_IFCHR ||
1339 				 archive_entry_filetype(entry) == AE_IFBLK))
1340 				archive_entry_set_rdev(entry, st->st_rdev);
1341 			if ((parsed_kws & (MTREE_HAS_GID | MTREE_HAS_GNAME))
1342 				== 0 ||
1343 			    (parsed_kws & MTREE_HAS_NOCHANGE) != 0)
1344 				archive_entry_set_gid(entry, st->st_gid);
1345 			if ((parsed_kws & (MTREE_HAS_UID | MTREE_HAS_UNAME))
1346 				== 0 ||
1347 			    (parsed_kws & MTREE_HAS_NOCHANGE) != 0)
1348 				archive_entry_set_uid(entry, st->st_uid);
1349 			if ((parsed_kws & MTREE_HAS_MTIME) == 0 ||
1350 			    (parsed_kws & MTREE_HAS_NOCHANGE) != 0) {
1351 #if HAVE_STRUCT_STAT_ST_MTIMESPEC_TV_NSEC
1352 				archive_entry_set_mtime(entry, st->st_mtime,
1353 						st->st_mtimespec.tv_nsec);
1354 #elif HAVE_STRUCT_STAT_ST_MTIM_TV_NSEC
1355 				archive_entry_set_mtime(entry, st->st_mtime,
1356 						st->st_mtim.tv_nsec);
1357 #elif HAVE_STRUCT_STAT_ST_MTIME_N
1358 				archive_entry_set_mtime(entry, st->st_mtime,
1359 						st->st_mtime_n);
1360 #elif HAVE_STRUCT_STAT_ST_UMTIME
1361 				archive_entry_set_mtime(entry, st->st_mtime,
1362 						st->st_umtime*1000);
1363 #elif HAVE_STRUCT_STAT_ST_MTIME_USEC
1364 				archive_entry_set_mtime(entry, st->st_mtime,
1365 						st->st_mtime_usec*1000);
1366 #else
1367 				archive_entry_set_mtime(entry, st->st_mtime, 0);
1368 #endif
1369 			}
1370 			if ((parsed_kws & MTREE_HAS_NLINK) == 0 ||
1371 			    (parsed_kws & MTREE_HAS_NOCHANGE) != 0)
1372 				archive_entry_set_nlink(entry, st->st_nlink);
1373 			if ((parsed_kws & MTREE_HAS_PERM) == 0 ||
1374 			    (parsed_kws & MTREE_HAS_NOCHANGE) != 0)
1375 				archive_entry_set_perm(entry, st->st_mode);
1376 			if ((parsed_kws & MTREE_HAS_SIZE) == 0 ||
1377 			    (parsed_kws & MTREE_HAS_NOCHANGE) != 0)
1378 				archive_entry_set_size(entry, st->st_size);
1379 			archive_entry_set_ino(entry, st->st_ino);
1380 			archive_entry_set_dev(entry, st->st_dev);
1381 
1382 			archive_entry_linkify(mtree->resolver, &entry,
1383 				&sparse_entry);
1384 		} else if (parsed_kws & MTREE_HAS_OPTIONAL) {
1385 			/*
1386 			 * Couldn't open the entry, stat it or the on-disk type
1387 			 * didn't match.  If this entry is optional, just
1388 			 * ignore it and read the next header entry.
1389 			 */
1390 			*use_next = 1;
1391 			return ARCHIVE_OK;
1392 		}
1393 	}
1394 
1395 	mtree->cur_size = archive_entry_size(entry);
1396 	mtree->offset = 0;
1397 
1398 	return r;
1399 }
1400 
1401 /*
1402  * Each line contains a sequence of keywords.
1403  */
1404 static int
1405 parse_line(struct archive_read *a, struct archive_entry *entry,
1406     struct mtree *mtree, struct mtree_entry *mp, int *parsed_kws)
1407 {
1408 	struct mtree_option *iter;
1409 	int r = ARCHIVE_OK, r1;
1410 
1411 	for (iter = mp->options; iter != NULL; iter = iter->next) {
1412 		r1 = parse_keyword(a, mtree, entry, iter, parsed_kws);
1413 		if (r1 < r)
1414 			r = r1;
1415 	}
1416 	if (r == ARCHIVE_OK && (*parsed_kws & MTREE_HAS_TYPE) == 0) {
1417 		archive_set_error(&a->archive, ARCHIVE_ERRNO_FILE_FORMAT,
1418 		    "Missing type keyword in mtree specification");
1419 		return (ARCHIVE_WARN);
1420 	}
1421 	return (r);
1422 }
1423 
1424 /*
1425  * Device entries have one of the following forms:
1426  *  - raw dev_t
1427  *  - format,major,minor[,subdevice]
1428  * When parsing succeeded, `pdev' will contain the appropriate dev_t value.
1429  */
1430 
1431 /* strsep() is not in C90, but strcspn() is. */
1432 /* Taken from http://unixpapa.com/incnote/string.html */
1433 static char *
1434 la_strsep(char **sp, const char *sep)
1435 {
1436 	char *p, *s;
1437 	if (sp == NULL || *sp == NULL || **sp == '\0')
1438 		return(NULL);
1439 	s = *sp;
1440 	p = s + strcspn(s, sep);
1441 	if (*p != '\0')
1442 		*p++ = '\0';
1443 	*sp = p;
1444 	return(s);
1445 }
1446 
1447 static int
1448 parse_device(dev_t *pdev, struct archive *a, char *val)
1449 {
1450 #define MAX_PACK_ARGS 3
1451 	unsigned long numbers[MAX_PACK_ARGS];
1452 	char *p, *dev;
1453 	int argc;
1454 	pack_t *pack;
1455 	dev_t result;
1456 	const char *error = NULL;
1457 
1458 	memset(pdev, 0, sizeof(*pdev));
1459 	if ((dev = strchr(val, ',')) != NULL) {
1460 		/*
1461 		 * Device's major/minor are given in a specified format.
1462 		 * Decode and pack it accordingly.
1463 		 */
1464 		*dev++ = '\0';
1465 		if ((pack = pack_find(val)) == NULL) {
1466 			archive_set_error(a, ARCHIVE_ERRNO_FILE_FORMAT,
1467 			    "Unknown format `%s'", val);
1468 			return ARCHIVE_WARN;
1469 		}
1470 		argc = 0;
1471 		while ((p = la_strsep(&dev, ",")) != NULL) {
1472 			if (*p == '\0') {
1473 				archive_set_error(a, ARCHIVE_ERRNO_FILE_FORMAT,
1474 				    "Missing number");
1475 				return ARCHIVE_WARN;
1476 			}
1477 			if (argc >= MAX_PACK_ARGS) {
1478 				archive_set_error(a, ARCHIVE_ERRNO_FILE_FORMAT,
1479 				    "Too many arguments");
1480 				return ARCHIVE_WARN;
1481 			}
1482 			numbers[argc++] = (unsigned long)mtree_atol(&p, 0);
1483 		}
1484 		if (argc < 2) {
1485 			archive_set_error(a, ARCHIVE_ERRNO_FILE_FORMAT,
1486 			    "Not enough arguments");
1487 			return ARCHIVE_WARN;
1488 		}
1489 		result = (*pack)(argc, numbers, &error);
1490 		if (error != NULL) {
1491 			archive_set_error(a, ARCHIVE_ERRNO_FILE_FORMAT,
1492 			    "%s", error);
1493 			return ARCHIVE_WARN;
1494 		}
1495 	} else {
1496 		/* file system raw value. */
1497 		result = (dev_t)mtree_atol(&val, 0);
1498 	}
1499 	*pdev = result;
1500 	return ARCHIVE_OK;
1501 #undef MAX_PACK_ARGS
1502 }
1503 
1504 static int
1505 parse_hex_nibble(char c)
1506 {
1507 	if (c >= '0' && c <= '9')
1508 		return c - '0';
1509 	if (c >= 'a' && c <= 'f')
1510 		return 10 + c - 'a';
1511 #if 0
1512 	/* XXX: Is uppercase something we should support? */
1513 	if (c >= 'A' && c <= 'F')
1514 		return 10 + c - 'A';
1515 #endif
1516 
1517 	return -1;
1518 }
1519 
1520 static int
1521 parse_digest(struct archive_read *a, struct archive_entry *entry,
1522     const char *digest, int type)
1523 {
1524 	unsigned char digest_buf[64];
1525 	int high, low;
1526 	size_t i, j, len;
1527 
1528 	switch (type) {
1529 	case ARCHIVE_ENTRY_DIGEST_MD5:
1530 		len = sizeof(entry->digest.md5);
1531 		break;
1532 	case ARCHIVE_ENTRY_DIGEST_RMD160:
1533 		len = sizeof(entry->digest.rmd160);
1534 		break;
1535 	case ARCHIVE_ENTRY_DIGEST_SHA1:
1536 		len = sizeof(entry->digest.sha1);
1537 		break;
1538 	case ARCHIVE_ENTRY_DIGEST_SHA256:
1539 		len = sizeof(entry->digest.sha256);
1540 		break;
1541 	case ARCHIVE_ENTRY_DIGEST_SHA384:
1542 		len = sizeof(entry->digest.sha384);
1543 		break;
1544 	case ARCHIVE_ENTRY_DIGEST_SHA512:
1545 		len = sizeof(entry->digest.sha512);
1546 		break;
1547 	default:
1548 		archive_set_error(&a->archive, ARCHIVE_ERRNO_PROGRAMMER,
1549 			"Internal error: Unknown digest type");
1550 		return ARCHIVE_FATAL;
1551 	}
1552 
1553 	if (len > sizeof(digest_buf)) {
1554 		archive_set_error(&a->archive, ARCHIVE_ERRNO_PROGRAMMER,
1555 			"Internal error: Digest storage too large");
1556 		return ARCHIVE_FATAL;
1557 	}
1558 
1559 	len *= 2;
1560 
1561 	if (mtree_strnlen(digest, len+1) != len) {
1562 		archive_set_error(&a->archive, ARCHIVE_ERRNO_FILE_FORMAT,
1563 				  "incorrect digest length, ignoring");
1564 		return ARCHIVE_WARN;
1565 	}
1566 
1567 	for (i = 0, j = 0; i < len; i += 2, j++) {
1568 		high = parse_hex_nibble(digest[i]);
1569 		low = parse_hex_nibble(digest[i+1]);
1570 		if (high == -1 || low == -1) {
1571 			archive_set_error(&a->archive, ARCHIVE_ERRNO_FILE_FORMAT,
1572 					  "invalid digest data, ignoring");
1573 			return ARCHIVE_WARN;
1574 		}
1575 
1576 		digest_buf[j] = high << 4 | low;
1577 	}
1578 
1579 	return archive_entry_set_digest(entry, type, digest_buf);
1580 }
1581 
1582 /*
1583  * Parse a single keyword and its value.
1584  */
1585 static int
1586 parse_keyword(struct archive_read *a, struct mtree *mtree,
1587     struct archive_entry *entry, struct mtree_option *opt, int *parsed_kws)
1588 {
1589 	char *val, *key;
1590 
1591 	key = opt->value;
1592 
1593 	if (*key == '\0')
1594 		return (ARCHIVE_OK);
1595 
1596 	if (strcmp(key, "nochange") == 0) {
1597 		*parsed_kws |= MTREE_HAS_NOCHANGE;
1598 		return (ARCHIVE_OK);
1599 	}
1600 	if (strcmp(key, "optional") == 0) {
1601 		*parsed_kws |= MTREE_HAS_OPTIONAL;
1602 		return (ARCHIVE_OK);
1603 	}
1604 	if (strcmp(key, "ignore") == 0) {
1605 		/*
1606 		 * The mtree processing is not recursive, so
1607 		 * recursion will only happen for explicitly listed
1608 		 * entries.
1609 		 */
1610 		return (ARCHIVE_OK);
1611 	}
1612 
1613 	val = strchr(key, '=');
1614 	if (val == NULL) {
1615 		archive_set_error(&a->archive, ARCHIVE_ERRNO_FILE_FORMAT,
1616 		    "Malformed attribute \"%s\" (%d)", key, key[0]);
1617 		return (ARCHIVE_WARN);
1618 	}
1619 
1620 	*val = '\0';
1621 	++val;
1622 
1623 	switch (key[0]) {
1624 	case 'c':
1625 		if (strcmp(key, "content") == 0
1626 		    || strcmp(key, "contents") == 0) {
1627 			parse_escapes(val, NULL);
1628 			archive_strcpy(&mtree->contents_name, val);
1629 			return (ARCHIVE_OK);
1630 		}
1631 		if (strcmp(key, "cksum") == 0)
1632 			return (ARCHIVE_OK);
1633 		break;
1634 	case 'd':
1635 		if (strcmp(key, "device") == 0) {
1636 			/* stat(2) st_rdev field, e.g. the major/minor IDs
1637 			 * of a char/block special file */
1638 			int r;
1639 			dev_t dev;
1640 
1641 			*parsed_kws |= MTREE_HAS_DEVICE;
1642 			r = parse_device(&dev, &a->archive, val);
1643 			if (r == ARCHIVE_OK)
1644 				archive_entry_set_rdev(entry, dev);
1645 			return r;
1646 		}
1647 		break;
1648 	case 'f':
1649 		if (strcmp(key, "flags") == 0) {
1650 			*parsed_kws |= MTREE_HAS_FFLAGS;
1651 			archive_entry_copy_fflags_text(entry, val);
1652 			return (ARCHIVE_OK);
1653 		}
1654 		break;
1655 	case 'g':
1656 		if (strcmp(key, "gid") == 0) {
1657 			*parsed_kws |= MTREE_HAS_GID;
1658 			archive_entry_set_gid(entry, mtree_atol(&val, 10));
1659 			return (ARCHIVE_OK);
1660 		}
1661 		if (strcmp(key, "gname") == 0) {
1662 			*parsed_kws |= MTREE_HAS_GNAME;
1663 			archive_entry_copy_gname(entry, val);
1664 			return (ARCHIVE_OK);
1665 		}
1666 		break;
1667 	case 'i':
1668 		if (strcmp(key, "inode") == 0) {
1669 			archive_entry_set_ino(entry, mtree_atol(&val, 10));
1670 			return (ARCHIVE_OK);
1671 		}
1672 		break;
1673 	case 'l':
1674 		if (strcmp(key, "link") == 0) {
1675 			parse_escapes(val, NULL);
1676 			archive_entry_copy_symlink(entry, val);
1677 			return (ARCHIVE_OK);
1678 		}
1679 		break;
1680 	case 'm':
1681 		if (strcmp(key, "md5") == 0 || strcmp(key, "md5digest") == 0) {
1682 			return parse_digest(a, entry, val,
1683 			    ARCHIVE_ENTRY_DIGEST_MD5);
1684 		}
1685 		if (strcmp(key, "mode") == 0) {
1686 			if (val[0] < '0' || val[0] > '7') {
1687 				archive_set_error(&a->archive,
1688 				    ARCHIVE_ERRNO_FILE_FORMAT,
1689 				    "Symbolic or non-octal mode \"%s\" unsupported", val);
1690 				return (ARCHIVE_WARN);
1691 			}
1692 			*parsed_kws |= MTREE_HAS_PERM;
1693 			archive_entry_set_perm(entry, (mode_t)mtree_atol(&val, 8));
1694 			return (ARCHIVE_OK);
1695 		}
1696 		break;
1697 	case 'n':
1698 		if (strcmp(key, "nlink") == 0) {
1699 			*parsed_kws |= MTREE_HAS_NLINK;
1700 			archive_entry_set_nlink(entry,
1701 				(unsigned int)mtree_atol(&val, 10));
1702 			return (ARCHIVE_OK);
1703 		}
1704 		break;
1705 	case 'r':
1706 		if (strcmp(key, "resdevice") == 0) {
1707 			/* stat(2) st_dev field, e.g. the device ID where the
1708 			 * inode resides */
1709 			int r;
1710 			dev_t dev;
1711 
1712 			r = parse_device(&dev, &a->archive, val);
1713 			if (r == ARCHIVE_OK)
1714 				archive_entry_set_dev(entry, dev);
1715 			return r;
1716 		}
1717 		if (strcmp(key, "rmd160") == 0 ||
1718 		    strcmp(key, "rmd160digest") == 0) {
1719 			return parse_digest(a, entry, val,
1720 			    ARCHIVE_ENTRY_DIGEST_RMD160);
1721 		}
1722 		break;
1723 	case 's':
1724 		if (strcmp(key, "sha1") == 0 ||
1725 		    strcmp(key, "sha1digest") == 0) {
1726 			return parse_digest(a, entry, val,
1727 			    ARCHIVE_ENTRY_DIGEST_SHA1);
1728 		}
1729 		if (strcmp(key, "sha256") == 0 ||
1730 		    strcmp(key, "sha256digest") == 0) {
1731 			return parse_digest(a, entry, val,
1732 			    ARCHIVE_ENTRY_DIGEST_SHA256);
1733 		}
1734 		if (strcmp(key, "sha384") == 0 ||
1735 		    strcmp(key, "sha384digest") == 0) {
1736 			return parse_digest(a, entry, val,
1737 			    ARCHIVE_ENTRY_DIGEST_SHA384);
1738 		}
1739 		if (strcmp(key, "sha512") == 0 ||
1740 		    strcmp(key, "sha512digest") == 0) {
1741 			return parse_digest(a, entry, val,
1742 			    ARCHIVE_ENTRY_DIGEST_SHA512);
1743 		}
1744 		if (strcmp(key, "size") == 0) {
1745 			archive_entry_set_size(entry, mtree_atol(&val, 10));
1746 			return (ARCHIVE_OK);
1747 		}
1748 		break;
1749 	case 't':
1750 		if (strcmp(key, "tags") == 0) {
1751 			/*
1752 			 * Comma delimited list of tags.
1753 			 * Ignore the tags for now, but the interface
1754 			 * should be extended to allow inclusion/exclusion.
1755 			 */
1756 			return (ARCHIVE_OK);
1757 		}
1758 		if (strcmp(key, "time") == 0) {
1759 			int64_t m;
1760 			int64_t my_time_t_max = get_time_t_max();
1761 			int64_t my_time_t_min = get_time_t_min();
1762 			long ns = 0;
1763 
1764 			*parsed_kws |= MTREE_HAS_MTIME;
1765 			m = mtree_atol(&val, 10);
1766 			/* Replicate an old mtree bug:
1767 			 * 123456789.1 represents 123456789
1768 			 * seconds and 1 nanosecond. */
1769 			if (*val == '.') {
1770 				++val;
1771 				ns = (long)mtree_atol(&val, 10);
1772 				if (ns < 0)
1773 					ns = 0;
1774 				else if (ns > 999999999)
1775 					ns = 999999999;
1776 			}
1777 			if (m > my_time_t_max)
1778 				m = my_time_t_max;
1779 			else if (m < my_time_t_min)
1780 				m = my_time_t_min;
1781 			archive_entry_set_mtime(entry, (time_t)m, ns);
1782 			return (ARCHIVE_OK);
1783 		}
1784 		if (strcmp(key, "type") == 0) {
1785 			switch (val[0]) {
1786 			case 'b':
1787 				if (strcmp(val, "block") == 0) {
1788 					*parsed_kws |= MTREE_HAS_TYPE;
1789 					archive_entry_set_filetype(entry,
1790 						AE_IFBLK);
1791 					return (ARCHIVE_OK);
1792 				}
1793 				break;
1794 			case 'c':
1795 				if (strcmp(val, "char") == 0) {
1796 					*parsed_kws |= MTREE_HAS_TYPE;
1797 					archive_entry_set_filetype(entry,
1798 						AE_IFCHR);
1799 					return (ARCHIVE_OK);
1800 				}
1801 				break;
1802 			case 'd':
1803 				if (strcmp(val, "dir") == 0) {
1804 					*parsed_kws |= MTREE_HAS_TYPE;
1805 					archive_entry_set_filetype(entry,
1806 						AE_IFDIR);
1807 					return (ARCHIVE_OK);
1808 				}
1809 				break;
1810 			case 'f':
1811 				if (strcmp(val, "fifo") == 0) {
1812 					*parsed_kws |= MTREE_HAS_TYPE;
1813 					archive_entry_set_filetype(entry,
1814 						AE_IFIFO);
1815 					return (ARCHIVE_OK);
1816 				}
1817 				if (strcmp(val, "file") == 0) {
1818 					*parsed_kws |= MTREE_HAS_TYPE;
1819 					archive_entry_set_filetype(entry,
1820 						AE_IFREG);
1821 					return (ARCHIVE_OK);
1822 				}
1823 				break;
1824 			case 'l':
1825 				if (strcmp(val, "link") == 0) {
1826 					*parsed_kws |= MTREE_HAS_TYPE;
1827 					archive_entry_set_filetype(entry,
1828 						AE_IFLNK);
1829 					return (ARCHIVE_OK);
1830 				}
1831 				break;
1832 			default:
1833 				break;
1834 			}
1835 			archive_set_error(&a->archive,
1836 			    ARCHIVE_ERRNO_FILE_FORMAT,
1837 			    "Unrecognized file type \"%s\"; "
1838 			    "assuming \"file\"", val);
1839 			archive_entry_set_filetype(entry, AE_IFREG);
1840 			return (ARCHIVE_WARN);
1841 		}
1842 		break;
1843 	case 'u':
1844 		if (strcmp(key, "uid") == 0) {
1845 			*parsed_kws |= MTREE_HAS_UID;
1846 			archive_entry_set_uid(entry, mtree_atol(&val, 10));
1847 			return (ARCHIVE_OK);
1848 		}
1849 		if (strcmp(key, "uname") == 0) {
1850 			*parsed_kws |= MTREE_HAS_UNAME;
1851 			archive_entry_copy_uname(entry, val);
1852 			return (ARCHIVE_OK);
1853 		}
1854 		break;
1855 	default:
1856 		break;
1857 	}
1858 	archive_set_error(&a->archive, ARCHIVE_ERRNO_FILE_FORMAT,
1859 	    "Unrecognized key %s=%s", key, val);
1860 	return (ARCHIVE_WARN);
1861 }
1862 
1863 static int
1864 read_data(struct archive_read *a, const void **buff, size_t *size,
1865     int64_t *offset)
1866 {
1867 	size_t bytes_to_read;
1868 	ssize_t bytes_read;
1869 	struct mtree *mtree;
1870 
1871 	mtree = (struct mtree *)(a->format->data);
1872 	if (mtree->fd < 0) {
1873 		*buff = NULL;
1874 		*offset = 0;
1875 		*size = 0;
1876 		return (ARCHIVE_EOF);
1877 	}
1878 	if (mtree->buff == NULL) {
1879 		mtree->buffsize = 64 * 1024;
1880 		mtree->buff = malloc(mtree->buffsize);
1881 		if (mtree->buff == NULL) {
1882 			archive_set_error(&a->archive, ENOMEM,
1883 			    "Can't allocate memory");
1884 			return (ARCHIVE_FATAL);
1885 		}
1886 	}
1887 
1888 	*buff = mtree->buff;
1889 	*offset = mtree->offset;
1890 	if ((int64_t)mtree->buffsize > mtree->cur_size - mtree->offset)
1891 		bytes_to_read = (size_t)(mtree->cur_size - mtree->offset);
1892 	else
1893 		bytes_to_read = mtree->buffsize;
1894 	bytes_read = read(mtree->fd, mtree->buff, bytes_to_read);
1895 	if (bytes_read < 0) {
1896 		archive_set_error(&a->archive, errno, "Can't read");
1897 		return (ARCHIVE_WARN);
1898 	}
1899 	if (bytes_read == 0) {
1900 		*size = 0;
1901 		return (ARCHIVE_EOF);
1902 	}
1903 	mtree->offset += bytes_read;
1904 	*size = bytes_read;
1905 	return (ARCHIVE_OK);
1906 }
1907 
1908 /* Skip does nothing except possibly close the contents file. */
1909 static int
1910 skip(struct archive_read *a)
1911 {
1912 	struct mtree *mtree;
1913 
1914 	mtree = (struct mtree *)(a->format->data);
1915 	if (mtree->fd >= 0) {
1916 		close(mtree->fd);
1917 		mtree->fd = -1;
1918 	}
1919 	return (ARCHIVE_OK);
1920 }
1921 
1922 /*
1923  * Since parsing backslash sequences always makes strings shorter,
1924  * we can always do this conversion in-place.
1925  */
1926 static void
1927 parse_escapes(char *src, struct mtree_entry *mentry)
1928 {
1929 	char *dest = src;
1930 	char c;
1931 
1932 	if (mentry != NULL && strcmp(src, ".") == 0)
1933 		mentry->full = 1;
1934 
1935 	while (*src != '\0') {
1936 		c = *src++;
1937 		if (c == '/' && mentry != NULL)
1938 			mentry->full = 1;
1939 		if (c == '\\') {
1940 			switch (src[0]) {
1941 			case '0':
1942 				if (src[1] < '0' || src[1] > '7') {
1943 					c = 0;
1944 					++src;
1945 					break;
1946 				}
1947 				/* FALLTHROUGH */
1948 			case '1':
1949 			case '2':
1950 			case '3':
1951 				if (src[1] >= '0' && src[1] <= '7' &&
1952 				    src[2] >= '0' && src[2] <= '7') {
1953 					c = (src[0] - '0') << 6;
1954 					c |= (src[1] - '0') << 3;
1955 					c |= (src[2] - '0');
1956 					src += 3;
1957 				}
1958 				break;
1959 			case 'a':
1960 				c = '\a';
1961 				++src;
1962 				break;
1963 			case 'b':
1964 				c = '\b';
1965 				++src;
1966 				break;
1967 			case 'f':
1968 				c = '\f';
1969 				++src;
1970 				break;
1971 			case 'n':
1972 				c = '\n';
1973 				++src;
1974 				break;
1975 			case 'r':
1976 				c = '\r';
1977 				++src;
1978 				break;
1979 			case 's':
1980 				c = ' ';
1981 				++src;
1982 				break;
1983 			case 't':
1984 				c = '\t';
1985 				++src;
1986 				break;
1987 			case 'v':
1988 				c = '\v';
1989 				++src;
1990 				break;
1991 			case '\\':
1992 				c = '\\';
1993 				++src;
1994 				break;
1995 			}
1996 		}
1997 		*dest++ = c;
1998 	}
1999 	*dest = '\0';
2000 }
2001 
2002 /* Parse a hex digit. */
2003 static int
2004 parsedigit(char c)
2005 {
2006 	if (c >= '0' && c <= '9')
2007 		return c - '0';
2008 	else if (c >= 'a' && c <= 'f')
2009 		return c - 'a';
2010 	else if (c >= 'A' && c <= 'F')
2011 		return c - 'A';
2012 	else
2013 		return -1;
2014 }
2015 
2016 /*
2017  * Note that this implementation does not (and should not!) obey
2018  * locale settings; you cannot simply substitute strtol here, since
2019  * it does obey locale.
2020  */
2021 static int64_t
2022 mtree_atol(char **p, int base)
2023 {
2024 	int64_t l, limit;
2025 	int digit, last_digit_limit;
2026 
2027 	if (base == 0) {
2028 		if (**p != '0')
2029 			base = 10;
2030 		else if ((*p)[1] == 'x' || (*p)[1] == 'X') {
2031 			*p += 2;
2032 			base = 16;
2033 		} else {
2034 			base = 8;
2035 		}
2036 	}
2037 
2038 	if (**p == '-') {
2039 		limit = INT64_MIN / base;
2040 		last_digit_limit = -(INT64_MIN % base);
2041 		++(*p);
2042 
2043 		l = 0;
2044 		digit = parsedigit(**p);
2045 		while (digit >= 0 && digit < base) {
2046 			if (l < limit || (l == limit && digit >= last_digit_limit))
2047 				return INT64_MIN;
2048 			l = (l * base) - digit;
2049 			digit = parsedigit(*++(*p));
2050 		}
2051 		return l;
2052 	} else {
2053 		limit = INT64_MAX / base;
2054 		last_digit_limit = INT64_MAX % base;
2055 
2056 		l = 0;
2057 		digit = parsedigit(**p);
2058 		while (digit >= 0 && digit < base) {
2059 			if (l > limit || (l == limit && digit > last_digit_limit))
2060 				return INT64_MAX;
2061 			l = (l * base) + digit;
2062 			digit = parsedigit(*++(*p));
2063 		}
2064 		return l;
2065 	}
2066 }
2067 
2068 /*
2069  * Returns length of line (including trailing newline)
2070  * or negative on error.  'start' argument is updated to
2071  * point to first character of line.
2072  */
2073 static ssize_t
2074 readline(struct archive_read *a, struct mtree *mtree, char **start,
2075     ssize_t limit)
2076 {
2077 	ssize_t bytes_read;
2078 	ssize_t total_size = 0;
2079 	ssize_t find_off = 0;
2080 	const void *t;
2081 	void *nl;
2082 	char *u;
2083 
2084 	/* Accumulate line in a line buffer. */
2085 	for (;;) {
2086 		/* Read some more. */
2087 		t = __archive_read_ahead(a, 1, &bytes_read);
2088 		if (t == NULL)
2089 			return (0);
2090 		if (bytes_read < 0)
2091 			return (ARCHIVE_FATAL);
2092 		nl = memchr(t, '\n', bytes_read);
2093 		/* If we found '\n', trim the read to end exactly there. */
2094 		if (nl != NULL) {
2095 			bytes_read = ((const char *)nl) - ((const char *)t) + 1;
2096 		}
2097 		if (total_size + bytes_read + 1 > limit) {
2098 			archive_set_error(&a->archive,
2099 			    ARCHIVE_ERRNO_FILE_FORMAT,
2100 			    "Line too long");
2101 			return (ARCHIVE_FATAL);
2102 		}
2103 		if (archive_string_ensure(&mtree->line,
2104 			total_size + bytes_read + 1) == NULL) {
2105 			archive_set_error(&a->archive, ENOMEM,
2106 			    "Can't allocate working buffer");
2107 			return (ARCHIVE_FATAL);
2108 		}
2109 		/* Append new bytes to string. */
2110 		memcpy(mtree->line.s + total_size, t, bytes_read);
2111 		__archive_read_consume(a, bytes_read);
2112 		total_size += bytes_read;
2113 		mtree->line.s[total_size] = '\0';
2114 
2115 		for (u = mtree->line.s + find_off; *u; ++u) {
2116 			if (u[0] == '\n') {
2117 				/* Ends with unescaped newline. */
2118 				*start = mtree->line.s;
2119 				return total_size;
2120 			} else if (u[0] == '#') {
2121 				/* Ends with comment sequence #...\n */
2122 				if (nl == NULL) {
2123 					/* But we've not found the \n yet */
2124 					break;
2125 				}
2126 			} else if (u[0] == '\\') {
2127 				if (u[1] == '\n') {
2128 					/* Trim escaped newline. */
2129 					total_size -= 2;
2130 					mtree->line.s[total_size] = '\0';
2131 					break;
2132 				} else if (u[1] != '\0') {
2133 					/* Skip the two-char escape sequence */
2134 					++u;
2135 				}
2136 			}
2137 		}
2138 		find_off = u - mtree->line.s;
2139 	}
2140 }
2141