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Date:: Mon Jun 4 18:54:13 2018 UTC
Message:: use macro instead of literal ".pack"
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1 /*
2  * Copyright (c) 2018 Stefan Sperling <stsp@openbsd.org>
3  *
4  * Permission to use, copy, modify, and distribute this software for any
5  * purpose with or without fee is hereby granted, provided that the above
6  * copyright notice and this permission notice appear in all copies.
7  *
8  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
9  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
10  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
11  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
12  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
13  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
14  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
15  */
16 
17 #include <sys/types.h>
18 #include <sys/stat.h>
19 #include <sys/queue.h>
20 
21 #include <dirent.h>
22 #include <fcntl.h>
23 #include <errno.h>
24 #include <stdio.h>
25 #include <stdint.h>
26 #include <stdlib.h>
27 #include <string.h>
28 #include <limits.h>
29 #include <sha1.h>
30 #include <endian.h>
31 #include <zlib.h>
32 
33 #include "got_error.h"
34 #include "got_object.h"
35 #include "got_repository.h"
36 #include "got_opentemp.h"
37 
38 #include "got_lib_sha1.h"
39 #include "got_lib_pack.h"
40 #include "got_lib_path.h"
41 #include "got_lib_delta.h"
42 #include "got_lib_zbuf.h"
43 #include "got_lib_object.h"
44 #include "got_lib_repository.h"
45 
46 #ifndef nitems
47 #define nitems(_a) (sizeof(_a) / sizeof((_a)[0]))
48 #endif
49 
50 #define GOT_PACK_PREFIX		"pack-"
51 #define GOT_PACKFILE_SUFFIX	".pack"
52 #define GOT_PACKIDX_SUFFIX		".idx"
53 #define GOT_PACKFILE_NAMELEN	(strlen(GOT_PACK_PREFIX) + \
54 				SHA1_DIGEST_STRING_LENGTH - 1 + \
55 				strlen(GOT_PACKFILE_SUFFIX))
56 #define GOT_PACKIDX_NAMELEN	(strlen(GOT_PACK_PREFIX) + \
57 				SHA1_DIGEST_STRING_LENGTH - 1 + \
58 				strlen(GOT_PACKIDX_SUFFIX))
59 
60 #ifndef MIN
61 #define	MIN(_a,_b) ((_a) < (_b) ? (_a) : (_b))
62 #endif
63 
64 static const struct got_error *
65 verify_fanout_table(uint32_t *fanout_table)
66 {
67 	int i;
68 
69 	for (i = 0; i < 0xff - 1; i++) {
70 		if (be32toh(fanout_table[i]) > be32toh(fanout_table[i + 1]))
71 			return got_error(GOT_ERR_BAD_PACKIDX);
72 	}
73 
74 	return NULL;
75 }
76 
77 static const struct got_error *
78 get_packfile_size(size_t *size, const char *path)
79 {
80 	struct stat sb;
81 	char *dot;
82 
83 	*size = 0;
84 
85 	dot = strrchr(path, '.');
86 	if (dot == NULL)
87 		return got_error(GOT_ERR_BAD_PATH);
88 
89 	/* Path must point to a pack index or to a pack file. */
90 	if (strcmp(dot, GOT_PACKIDX_SUFFIX) == 0) {
91 		const struct got_error *err = NULL;
92 		char *path_pack;
93 		char base_path[PATH_MAX];
94 
95 		/* Convert pack index path to pack file path. */
96 		if (strlcpy(base_path, path, PATH_MAX) > PATH_MAX)
97 			return got_error(GOT_ERR_NO_SPACE);
98 		dot = strrchr(base_path, '.');
99 		if (dot == NULL)
100 			return got_error(GOT_ERR_BAD_PATH);
101 		*dot = '\0';
102 		if (asprintf(&path_pack, "%s.pack", base_path) == -1)
103 			return got_error_from_errno();
104 
105 		if (stat(path_pack, &sb) != 0)
106 			err = got_error_from_errno();
107 		free(path_pack);
108 		if (err)
109 			return err;
110 	} else if (strcmp(dot, GOT_PACKFILE_SUFFIX) == 0) {
111 		if (stat(path, &sb) != 0)
112 			return got_error_from_errno();
113 	} else
114 		return got_error(GOT_ERR_BAD_PATH);
115 
116 	*size = sb.st_size;
117 	return 0;
118 }
119 
120 const struct got_error *
121 got_packidx_open(struct got_packidx **packidx, const char *path)
122 {
123 	struct got_packidx *p;
124 	struct got_packidx_v2_hdr *h;
125 	FILE *f;
126 	const struct got_error *err = NULL;
127 	size_t n, nobj, packfile_size;
128 	SHA1_CTX ctx;
129 	uint8_t sha1[SHA1_DIGEST_LENGTH];
130 
131 	*packidx = NULL;
132 
133 	SHA1Init(&ctx);
134 
135 	f = fopen(path, "rb");
136 	if (f == NULL)
137 		return got_error_from_errno();
138 
139 	err = get_packfile_size(&packfile_size, path);
140 	if (err)
141 		return err;
142 
143 	p = calloc(1, sizeof(*p));
144 	if (p == NULL)
145 		return got_error_from_errno();
146 	p->path_packidx = strdup(path);
147 	if (p->path_packidx == NULL) {
148 		err = got_error_from_errno();
149 		free(p->path_packidx);
150 		free(p);
151 		return err;
152 	}
153 
154 	h = &p->hdr;
155 	n = fread(&h->magic, sizeof(h->magic), 1, f);
156 	if (n != 1) {
157 		err = got_ferror(f, GOT_ERR_BAD_PACKIDX);
158 		goto done;
159 	}
160 
161 	if (betoh32(h->magic) != GOT_PACKIDX_V2_MAGIC) {
162 		err = got_error(GOT_ERR_BAD_PACKIDX);
163 		goto done;
164 	}
165 
166 	SHA1Update(&ctx, (uint8_t *)&h->magic, sizeof(h->magic));
167 
168 	n = fread(&h->version, sizeof(h->version), 1, f);
169 	if (n != 1) {
170 		err = got_ferror(f, GOT_ERR_BAD_PACKIDX);
171 		goto done;
172 	}
173 
174 	if (betoh32(h->version) != GOT_PACKIDX_VERSION) {
175 		err = got_error(GOT_ERR_BAD_PACKIDX);
176 		goto done;
177 	}
178 
179 	SHA1Update(&ctx, (uint8_t *)&h->version, sizeof(h->version));
180 
181 	n = fread(&h->fanout_table, sizeof(h->fanout_table), 1, f);
182 	if (n != 1) {
183 		err = got_ferror(f, GOT_ERR_BAD_PACKIDX);
184 		goto done;
185 	}
186 
187 	err = verify_fanout_table(h->fanout_table);
188 	if (err)
189 		goto done;
190 
191 	SHA1Update(&ctx, (uint8_t *)h->fanout_table, sizeof(h->fanout_table));
192 
193 	nobj = betoh32(h->fanout_table[0xff]);
194 
195 	h->sorted_ids = calloc(nobj, sizeof(*h->sorted_ids));
196 	if (h->sorted_ids == NULL) {
197 		err = got_error_from_errno();
198 		goto done;
199 	}
200 
201 	n = fread(h->sorted_ids, sizeof(*h->sorted_ids), nobj, f);
202 	if (n != nobj) {
203 		err = got_ferror(f, GOT_ERR_BAD_PACKIDX);
204 		goto done;
205 	}
206 
207 	SHA1Update(&ctx, (uint8_t *)h->sorted_ids,
208 	    nobj * sizeof(*h->sorted_ids));
209 
210 	h->crc32 = calloc(nobj, sizeof(*h->crc32));
211 	if (h->crc32 == NULL) {
212 		err = got_error_from_errno();
213 		goto done;
214 	}
215 
216 	n = fread(h->crc32, sizeof(*h->crc32), nobj, f);
217 	if (n != nobj) {
218 		err = got_ferror(f, GOT_ERR_BAD_PACKIDX);
219 		goto done;
220 	}
221 
222 	SHA1Update(&ctx, (uint8_t *)h->crc32, nobj * sizeof(*h->crc32));
223 
224 	h->offsets = calloc(nobj, sizeof(*h->offsets));
225 	if (h->offsets == NULL) {
226 		err = got_error_from_errno();
227 		goto done;
228 	}
229 
230 	n = fread(h->offsets, sizeof(*h->offsets), nobj, f);
231 	if (n != nobj) {
232 		err = got_ferror(f, GOT_ERR_BAD_PACKIDX);
233 		goto done;
234 	}
235 
236 	SHA1Update(&ctx, (uint8_t *)h->offsets, nobj * sizeof(*h->offsets));
237 
238 	/* Large file offsets are contained only in files > 2GB. */
239 	if (packfile_size <= 0x80000000)
240 		goto checksum;
241 
242 	h->large_offsets = calloc(nobj, sizeof(*h->large_offsets));
243 	if (h->large_offsets == NULL) {
244 		err = got_error_from_errno();
245 		goto done;
246 	}
247 
248 	n = fread(h->large_offsets, sizeof(*h->large_offsets), nobj, f);
249 	if (n != nobj) {
250 		err = got_ferror(f, GOT_ERR_BAD_PACKIDX);
251 		goto done;
252 	}
253 
254 	SHA1Update(&ctx, (uint8_t*)h->large_offsets,
255 	    nobj * sizeof(*h->large_offsets));
256 
257 checksum:
258 	n = fread(&h->trailer, sizeof(h->trailer), 1, f);
259 	if (n != 1) {
260 		err = got_ferror(f, GOT_ERR_BAD_PACKIDX);
261 		goto done;
262 	}
263 
264 	SHA1Update(&ctx, h->trailer.packfile_sha1, SHA1_DIGEST_LENGTH);
265 	SHA1Final(sha1, &ctx);
266 	if (memcmp(h->trailer.packidx_sha1, sha1, SHA1_DIGEST_LENGTH) != 0)
267 		err = got_error(GOT_ERR_PACKIDX_CSUM);
268 done:
269 	fclose(f);
270 	if (err)
271 		got_packidx_close(p);
272 	else
273 		*packidx = p;
274 	return err;
275 }
276 
277 void
278 got_packidx_close(struct got_packidx *packidx)
279 {
280 	free(packidx->hdr.sorted_ids);
281 	free(packidx->hdr.offsets);
282 	free(packidx->hdr.crc32);
283 	free(packidx->hdr.large_offsets);
284 	free(packidx->path_packidx);
285 	free(packidx);
286 }
287 
288 static int
289 is_packidx_filename(const char *name, size_t len)
290 {
291 	if (len != GOT_PACKIDX_NAMELEN)
292 		return 0;
293 
294 	if (strncmp(name, GOT_PACK_PREFIX, strlen(GOT_PACK_PREFIX)) != 0)
295 		return 0;
296 
297 	if (strcmp(name + strlen(GOT_PACK_PREFIX) +
298 	    SHA1_DIGEST_STRING_LENGTH - 1, GOT_PACKIDX_SUFFIX) != 0)
299 		return 0;
300 
301 	return 1;
302 }
303 
304 static off_t
305 get_object_offset(struct got_packidx *packidx, int idx)
306 {
307 	uint32_t totobj = betoh32(packidx->hdr.fanout_table[0xff]);
308 	uint32_t offset = betoh32(packidx->hdr.offsets[idx]);
309 	if (offset & GOT_PACKIDX_OFFSET_VAL_IS_LARGE_IDX) {
310 		uint64_t loffset;
311 		idx = offset & GOT_PACKIDX_OFFSET_VAL_MASK;
312 		if (idx < 0 || idx > totobj ||
313 		    packidx->hdr.large_offsets == NULL)
314 			return -1;
315 		loffset = betoh64(packidx->hdr.large_offsets[idx]);
316 		return (loffset > INT64_MAX ? -1 : (off_t)loffset);
317 	}
318 	return (off_t)(offset & GOT_PACKIDX_OFFSET_VAL_MASK);
319 }
320 
321 static int
322 get_object_idx(struct got_packidx *packidx, struct got_object_id *id,
323     struct got_repository *repo)
324 {
325 	u_int8_t id0 = id->sha1[0];
326 	uint32_t totobj = betoh32(packidx->hdr.fanout_table[0xff]);
327 	int i = 0;
328 
329 	if (id0 > 0)
330 		i = betoh32(packidx->hdr.fanout_table[id0 - 1]);
331 
332 	while (i < totobj) {
333 		struct got_object_id *oid = &packidx->hdr.sorted_ids[i];
334 		int cmp = got_object_id_cmp(id, oid);
335 
336 		if (cmp == 0)
337 			return i;
338 		i++;
339 	}
340 
341 	return -1;
342 }
343 
344 static struct got_packidx *
345 dup_packidx(struct got_packidx *packidx)
346 {
347 	struct got_packidx *p;
348 	size_t nobj;
349 
350 	p = calloc(1, sizeof(*p));
351 	if (p == NULL)
352 		return NULL;
353 
354 	p->path_packidx = strdup(packidx->path_packidx);
355 	if (p->path_packidx == NULL) {
356 		free(p);
357 		return NULL;
358 	}
359 	memcpy(&p->hdr, &packidx->hdr, sizeof(p->hdr));
360 	p->hdr.sorted_ids = NULL;
361 	p->hdr.crc32 = NULL;
362 	p->hdr.offsets = NULL;
363 	p->hdr.large_offsets = NULL;
364 
365 	nobj = betoh32(p->hdr.fanout_table[0xff]);
366 
367 	p->hdr.sorted_ids = calloc(nobj, sizeof(*p->hdr.sorted_ids));
368 	if (p->hdr.sorted_ids == NULL)
369 		goto err;
370 	memcpy(p->hdr.sorted_ids, packidx->hdr.sorted_ids,
371 	    nobj * sizeof(*p->hdr.sorted_ids));
372 
373 	p->hdr.crc32 = calloc(nobj, sizeof(*p->hdr.crc32));
374 	if (p->hdr.crc32 == NULL)
375 		goto err;
376 	memcpy(p->hdr.crc32, packidx->hdr.crc32, nobj * sizeof(*p->hdr.crc32));
377 
378 	p->hdr.offsets = calloc(nobj, sizeof(*p->hdr.offsets));
379 	if (p->hdr.offsets == NULL)
380 		goto err;
381 	memcpy(p->hdr.offsets, packidx->hdr.offsets,
382 	    nobj * sizeof(*p->hdr.offsets));
383 
384 	if (p->hdr.large_offsets) {
385 		p->hdr.large_offsets = calloc(nobj,
386 		    sizeof(*p->hdr.large_offsets));
387 		if (p->hdr.large_offsets == NULL)
388 			goto err;
389 		memcpy(p->hdr.large_offsets, packidx->hdr.large_offsets,
390 		    nobj * sizeof(*p->hdr.large_offsets));
391 	}
392 
393 	return p;
394 
395 err:
396 	free(p->hdr.large_offsets);
397 	free(p->hdr.offsets);
398 	free(p->hdr.crc32);
399 	free(p->hdr.sorted_ids);
400 	free(p->path_packidx);
401 	free(p);
402 	return NULL;
403 }
404 
405 static void
406 cache_packidx(struct got_packidx *packidx, struct got_repository *repo)
407 {
408 	int i;
409 
410 	for (i = 0; i < nitems(repo->packidx_cache); i++) {
411 		if (repo->packidx_cache[i] == NULL)
412 			break;
413 	}
414 
415 	if (i == nitems(repo->packidx_cache)) {
416 		got_packidx_close(repo->packidx_cache[i - 1]);
417 		memmove(&repo->packidx_cache[1], &repo->packidx_cache[0],
418 		    sizeof(repo->packidx_cache) -
419 		    sizeof(repo->packidx_cache[0]));
420 		i = 0;
421 	}
422 
423 	repo->packidx_cache[i] = dup_packidx(packidx);
424 }
425 
426 static const struct got_error *
427 search_packidx(struct got_packidx **packidx, int *idx,
428     struct got_repository *repo, struct got_object_id *id)
429 {
430 	const struct got_error *err;
431 	char *path_packdir;
432 	DIR *packdir;
433 	struct dirent *dent;
434 	char *path_packidx;
435 	int i;
436 
437 	/* Search pack index cache. */
438 	for (i = 0; i < nitems(repo->packidx_cache); i++) {
439 		if (repo->packidx_cache[i] == NULL)
440 			break;
441 		*idx = get_object_idx(repo->packidx_cache[i], id, repo);
442 		if (*idx != -1) {
443 			*packidx = repo->packidx_cache[i];
444 			return NULL;
445 		}
446 	}
447 	/* No luck. Search the filesystem. */
448 
449 	path_packdir = got_repo_get_path_objects_pack(repo);
450 	if (path_packdir == NULL)
451 		return got_error_from_errno();
452 
453 	packdir = opendir(path_packdir);
454 	if (packdir == NULL) {
455 		err = got_error_from_errno();
456 		goto done;
457 	}
458 
459 	while ((dent = readdir(packdir)) != NULL) {
460 		if (!is_packidx_filename(dent->d_name, dent->d_namlen))
461 			continue;
462 
463 		if (asprintf(&path_packidx, "%s/%s", path_packdir,
464 		    dent->d_name) == -1) {
465 			err = got_error_from_errno();
466 			goto done;
467 		}
468 
469 		err = got_packidx_open(packidx, path_packidx);
470 		free(path_packidx);
471 		if (err)
472 			goto done;
473 
474 		*idx = get_object_idx(*packidx, id, repo);
475 		if (*idx != -1) {
476 			err = NULL; /* found the object */
477 			cache_packidx(*packidx, repo);
478 			goto done;
479 		}
480 
481 		got_packidx_close(*packidx);
482 		*packidx = NULL;
483 	}
484 
485 	err = got_error(GOT_ERR_NO_OBJ);
486 done:
487 	free(path_packdir);
488 	if (packdir && closedir(packdir) != 0 && err == 0)
489 		err = got_error_from_errno();
490 	return err;
491 }
492 
493 static const struct got_error *
494 get_packfile_path(char **path_packfile, struct got_repository *repo,
495     struct got_packidx *packidx)
496 {
497 	size_t size;
498 
499 	/* Packfile path contains ".pack" instead of ".idx", so add one byte. */
500 	size = strlen(packidx->path_packidx) + 2;
501 	if (size < GOT_PACKFILE_NAMELEN + 1)
502 		return got_error(GOT_ERR_BAD_PATH);
503 
504 	*path_packfile = calloc(size, sizeof(**path_packfile));
505 	if (*path_packfile == NULL)
506 		return got_error_from_errno();
507 
508 	/* Copy up to and excluding ".idx". */
509 	if (strlcpy(*path_packfile, packidx->path_packidx,
510 	    size - strlen(GOT_PACKIDX_SUFFIX) - 1) >= size)
511 		return got_error(GOT_ERR_NO_SPACE);
512 
513 	if (strlcat(*path_packfile, GOT_PACKFILE_SUFFIX, size) >= size)
514 		return got_error(GOT_ERR_NO_SPACE);
515 
516 	return NULL;
517 }
518 
519 const struct got_error *
520 read_packfile_hdr(int fd, struct got_packidx *packidx)
521 {
522 	const struct got_error *err = NULL;
523 	uint32_t totobj = betoh32(packidx->hdr.fanout_table[0xff]);
524 	struct got_packfile_hdr hdr;
525 	ssize_t n;
526 
527 	n = read(fd, &hdr, sizeof(hdr));
528 	if (n < 0)
529 		return got_error_from_errno();
530 	if (n != sizeof(hdr))
531 		return got_error(GOT_ERR_BAD_PACKFILE);
532 
533 	if (betoh32(hdr.signature) != GOT_PACKFILE_SIGNATURE ||
534 	    betoh32(hdr.version) != GOT_PACKFILE_VERSION ||
535 	    betoh32(hdr.nobjects) != totobj)
536 		err = got_error(GOT_ERR_BAD_PACKFILE);
537 
538 	return err;
539 }
540 
541 static const struct got_error *
542 open_packfile(int *fd, const char *path_packfile,
543     struct got_repository *repo, struct got_packidx *packidx)
544 {
545 	const struct got_error *err = NULL;
546 
547 	*fd = open(path_packfile, O_RDONLY | O_NOFOLLOW, GOT_DEFAULT_FILE_MODE);
548 	if (*fd == -1)
549 		return got_error_from_errno();
550 
551 	if (packidx) {
552 		err = read_packfile_hdr(*fd, packidx);
553 		if (err) {
554 			close(*fd);
555 			*fd = -1;
556 		}
557 	}
558 	return err;
559 }
560 
561 void
562 got_pack_close(struct got_pack *pack)
563 {
564 	close(pack->fd);
565 	pack->fd = -1;
566 	free(pack->path_packfile);
567 	pack->path_packfile = NULL;
568 	pack->filesize = 0;
569 }
570 
571 static const struct got_error *
572 cache_pack(struct got_pack **packp, const char *path_packfile,
573     struct got_packidx *packidx, struct got_repository *repo)
574 {
575 	const struct got_error *err = NULL;
576 	struct got_pack *pack = NULL;
577 	int i;
578 
579 	if (packp)
580 		*packp = NULL;
581 
582 	for (i = 0; i < nitems(repo->packs); i++) {
583 		pack = &repo->packs[i];
584 		if (pack->path_packfile == NULL)
585 			break;
586 		if (strcmp(pack->path_packfile, path_packfile) == 0)
587 			return NULL;
588 	}
589 
590 	if (i == nitems(repo->packs) - 1) {
591 		got_pack_close(&repo->packs[i - 1]);
592 		memmove(&repo->packs[1], &repo->packs[0],
593 		    sizeof(repo->packs) - sizeof(repo->packs[0]));
594 		i = 0;
595 	}
596 
597 	pack = &repo->packs[i];
598 
599 	pack->path_packfile = strdup(path_packfile);
600 	if (pack->path_packfile == NULL) {
601 		err = got_error_from_errno();
602 		goto done;
603 	}
604 
605 	err = open_packfile(&pack->fd, path_packfile, repo, packidx);
606 	if (err)
607 		goto done;
608 
609 	err = get_packfile_size(&pack->filesize, path_packfile);
610 done:
611 	if (err) {
612 		if (pack) {
613 			free(pack->path_packfile);
614 			memset(pack, 0, sizeof(*pack));
615 		}
616 	} else if (packp)
617 		*packp = pack;
618 	return err;
619 }
620 
621 struct got_pack *
622 get_cached_pack(const char *path_packfile, struct got_repository *repo)
623 {
624 	struct got_pack *pack = NULL;
625 	int i;
626 
627 	for (i = 0; i < nitems(repo->packs); i++) {
628 		pack = &repo->packs[i];
629 		if (pack->path_packfile == NULL)
630 			break;
631 		if (strcmp(pack->path_packfile, path_packfile) == 0)
632 			return pack;
633 	}
634 
635 	return NULL;
636 }
637 
638 static const struct got_error *
639 parse_object_type_and_size(uint8_t *type, uint64_t *size, size_t *len, int fd)
640 {
641 	uint8_t t = 0;
642 	uint64_t s = 0;
643 	uint8_t sizeN;
644 	ssize_t n;
645 	int i = 0;
646 
647 	do {
648 		/* We do not support size values which don't fit in 64 bit. */
649 		if (i > 9)
650 			return got_error(GOT_ERR_NO_SPACE);
651 
652 		n = read(fd, &sizeN, sizeof(sizeN));
653 		if (n < 0)
654 			return got_error_from_errno();
655 		if (n != sizeof(sizeN))
656 			return got_error(GOT_ERR_BAD_PACKFILE);
657 
658 		if (i == 0) {
659 			t = (sizeN & GOT_PACK_OBJ_SIZE0_TYPE_MASK) >>
660 			    GOT_PACK_OBJ_SIZE0_TYPE_MASK_SHIFT;
661 			s = (sizeN & GOT_PACK_OBJ_SIZE0_VAL_MASK);
662 		} else {
663 			size_t shift = 4 + 7 * (i - 1);
664 			s |= ((sizeN & GOT_PACK_OBJ_SIZE_VAL_MASK) << shift);
665 		}
666 		i++;
667 	} while (sizeN & GOT_PACK_OBJ_SIZE_MORE);
668 
669 	*type = t;
670 	*size = s;
671 	*len = i * sizeof(sizeN);
672 	return NULL;
673 }
674 
675 static const struct got_error *
676 open_plain_object(struct got_object **obj, const char *path_packfile,
677     struct got_object_id *id, uint8_t type, off_t offset, size_t size)
678 {
679 	*obj = calloc(1, sizeof(**obj));
680 	if (*obj == NULL)
681 		return got_error_from_errno();
682 
683 	(*obj)->path_packfile = strdup(path_packfile);
684 	if ((*obj)->path_packfile == NULL) {
685 		const struct got_error *err = got_error_from_errno();
686 		free(*obj);
687 		*obj = NULL;
688 		return err;
689 	}
690 
691 	(*obj)->type = type;
692 	(*obj)->flags = GOT_OBJ_FLAG_PACKED;
693 	(*obj)->hdrlen = 0;
694 	(*obj)->size = size;
695 	memcpy(&(*obj)->id, id, sizeof((*obj)->id));
696 	(*obj)->pack_offset = offset;
697 
698 	return NULL;
699 }
700 
701 static const struct got_error *
702 parse_negative_offset(int64_t *offset, size_t *len, int fd)
703 {
704 	int64_t o = 0;
705 	uint8_t offN;
706 	ssize_t n;
707 	int i = 0;
708 
709 	do {
710 		/* We do not support offset values which don't fit in 64 bit. */
711 		if (i > 8)
712 			return got_error(GOT_ERR_NO_SPACE);
713 
714 		n = read(fd, &offN, sizeof(offN));
715 		if (n < 0)
716 			return got_error_from_errno();
717 		if (n != sizeof(offN))
718 			return got_error(GOT_ERR_BAD_PACKFILE);
719 
720 		if (i == 0)
721 			o = (offN & GOT_PACK_OBJ_DELTA_OFF_VAL_MASK);
722 		else {
723 			o++;
724 			o <<= 7;
725 			o += (offN & GOT_PACK_OBJ_DELTA_OFF_VAL_MASK);
726 		}
727 		i++;
728 	} while (offN & GOT_PACK_OBJ_DELTA_OFF_MORE);
729 
730 	*offset = o;
731 	*len = i * sizeof(offN);
732 	return NULL;
733 }
734 
735 static const struct got_error *
736 parse_offset_delta(off_t *base_offset, int fd, off_t offset)
737 {
738 	const struct got_error *err;
739 	int64_t negoffset;
740 	size_t negofflen;
741 
742 	err = parse_negative_offset(&negoffset, &negofflen, fd);
743 	if (err)
744 		return err;
745 
746 	/* Compute the base object's offset (must be in the same pack file). */
747 	*base_offset = (offset - negoffset);
748 	if (*base_offset <= 0)
749 		return got_error(GOT_ERR_BAD_PACKFILE);
750 
751 	return NULL;
752 }
753 
754 static const struct got_error *
755 resolve_delta_chain(struct got_delta_chain *, struct got_repository *,
756     int, size_t, const char *, off_t, size_t, int, size_t, unsigned int);
757 
758 static const struct got_error *
759 add_delta(struct got_delta_chain *deltas, const char *path_packfile,
760     off_t delta_offset, size_t tslen, int delta_type, size_t delta_size,
761     size_t delta_data_offset, uint8_t *delta_buf, size_t delta_len)
762 {
763 	struct got_delta *delta;
764 
765 	delta = got_delta_open(path_packfile, delta_offset, tslen,
766 	    delta_type, delta_size, delta_data_offset, delta_buf,
767 	    delta_len);
768 	if (delta == NULL)
769 		return got_error_from_errno();
770 	/* delta is freed in got_object_close() */
771 	deltas->nentries++;
772 	SIMPLEQ_INSERT_HEAD(&deltas->entries, delta, entry);
773 	return NULL;
774 }
775 
776 static const struct got_error *
777 resolve_offset_delta(struct got_delta_chain *deltas,
778     struct got_repository *repo, int fd, size_t packfile_size,
779     const char *path_packfile, off_t delta_offset, size_t tslen,
780     int delta_type, size_t delta_size, unsigned int recursion)
781 
782 {
783 	const struct got_error *err;
784 	off_t base_offset;
785 	uint8_t base_type;
786 	uint64_t base_size;
787 	size_t base_tslen;
788 	off_t delta_data_offset;
789 	uint8_t *delta_buf;
790 	size_t delta_len;
791 
792 	err = parse_offset_delta(&base_offset, fd, delta_offset);
793 	if (err)
794 		return err;
795 
796 	delta_data_offset = lseek(fd, 0, SEEK_CUR);
797 	if (delta_data_offset == -1)
798 		return got_error_from_errno();
799 
800 	err = got_inflate_to_mem_fd(&delta_buf, &delta_len, fd);
801 	if (err)
802 		return err;
803 
804 	err = add_delta(deltas, path_packfile, delta_offset, tslen,
805 	    delta_type, delta_size, delta_data_offset, delta_buf, delta_len);
806 	if (err)
807 		return err;
808 
809 	/* An offset delta must be in the same packfile. */
810 	if (base_offset >= packfile_size)
811 		return got_error(GOT_ERR_PACK_OFFSET);
812 	if (lseek(fd, base_offset, SEEK_SET) == -1)
813 		return got_error_from_errno();
814 
815 	err = parse_object_type_and_size(&base_type, &base_size, &base_tslen,
816 	    fd);
817 	if (err)
818 		return err;
819 
820 	return resolve_delta_chain(deltas, repo, fd, packfile_size,
821 	    path_packfile, base_offset, base_tslen, base_type, base_size,
822 	    recursion - 1);
823 }
824 
825 static const struct got_error *
826 resolve_ref_delta(struct got_delta_chain *deltas, struct got_repository *repo,
827     int fd, const char *path_packfile, off_t delta_offset,
828     size_t tslen, int delta_type, size_t delta_size, unsigned int recursion)
829 {
830 	const struct got_error *err;
831 	struct got_object_id id;
832 	struct got_packidx *packidx;
833 	int idx;
834 	off_t base_offset;
835 	uint8_t base_type;
836 	uint64_t base_size;
837 	size_t base_tslen;
838 	ssize_t n;
839 	char *path_base_packfile;
840 	struct got_pack *base_pack;
841 	off_t delta_data_offset;
842 	uint8_t *delta_buf;
843 	size_t delta_len;
844 
845 	n = read(fd, &id, sizeof(id));
846 	if (n < 0)
847 		return got_error_from_errno();
848 	if (n != sizeof(id))
849 		return got_error(GOT_ERR_BAD_PACKFILE);
850 
851 	delta_data_offset = lseek(fd, 0, SEEK_CUR);
852 	if (delta_data_offset == -1)
853 		return got_error_from_errno();
854 
855 	err = got_inflate_to_mem_fd(&delta_buf, &delta_len, fd);
856 	if (err)
857 		return err;
858 
859 	err = add_delta(deltas, path_packfile, delta_offset, tslen,
860 	    delta_type, delta_size, delta_data_offset, delta_buf, delta_len);
861 	if (err)
862 		return err;
863 
864 	err = search_packidx(&packidx, &idx, repo, &id);
865 	if (err)
866 		return err;
867 
868 	base_offset = get_object_offset(packidx, idx);
869 	if (base_offset == (uint64_t)-1) {
870 		return got_error(GOT_ERR_BAD_PACKIDX);
871 	}
872 
873 	err = get_packfile_path(&path_base_packfile, repo, packidx);
874 	if (err)
875 		return err;
876 
877 	base_pack = get_cached_pack(path_base_packfile, repo);
878 	if (base_pack == NULL) {
879 		err = cache_pack(&base_pack, path_base_packfile, NULL, repo);
880 		if (err)
881 			goto done;
882 	}
883 
884 	if (base_offset >= base_pack->filesize) {
885 		err = got_error(GOT_ERR_PACK_OFFSET);
886 		goto done;
887 	}
888 	if (lseek(base_pack->fd, base_offset, SEEK_SET) == -1) {
889 		err = got_error_from_errno();
890 		goto done;
891 	}
892 
893 	err = parse_object_type_and_size(&base_type, &base_size, &base_tslen,
894 	    base_pack->fd);
895 	if (err)
896 		goto done;
897 
898 	err = resolve_delta_chain(deltas, repo, base_pack->fd,
899 	    base_pack->filesize, path_base_packfile, base_offset,
900 	    base_tslen, base_type, base_size, recursion - 1);
901 done:
902 	free(path_base_packfile);
903 	return err;
904 }
905 
906 static const struct got_error *
907 resolve_delta_chain(struct got_delta_chain *deltas, struct got_repository *repo,
908     int fd, size_t packfile_size, const char *path_packfile, off_t delta_offset,
909     size_t tslen, int delta_type, size_t delta_size, unsigned int recursion)
910 {
911 	const struct got_error *err = NULL;
912 
913 	if (--recursion == 0)
914 		return got_error(GOT_ERR_RECURSION);
915 
916 	switch (delta_type) {
917 	case GOT_OBJ_TYPE_COMMIT:
918 	case GOT_OBJ_TYPE_TREE:
919 	case GOT_OBJ_TYPE_BLOB:
920 	case GOT_OBJ_TYPE_TAG:
921 		/* Plain types are the final delta base. Recursion ends. */
922 		err = add_delta(deltas, path_packfile, delta_offset, tslen,
923 		    delta_type, delta_size, 0, NULL, 0);
924 		break;
925 	case GOT_OBJ_TYPE_OFFSET_DELTA:
926 		err = resolve_offset_delta(deltas, repo, fd, packfile_size,
927 		    path_packfile, delta_offset, tslen, delta_type, delta_size,
928 		    recursion - 1);
929 		break;
930 	case GOT_OBJ_TYPE_REF_DELTA:
931 		err = resolve_ref_delta(deltas, repo, fd, path_packfile,
932 		    delta_offset, tslen, delta_type, delta_size, recursion - 1);
933 		break;
934 	default:
935 		return got_error(GOT_ERR_OBJ_TYPE);
936 	}
937 
938 	return err;
939 }
940 
941 static const struct got_error *
942 open_delta_object(struct got_object **obj, struct got_repository *repo,
943     const char *path_packfile, int fd, size_t packfile_size,
944     struct got_object_id *id, off_t offset, size_t tslen,
945     int delta_type, size_t delta_size)
946 {
947 	const struct got_error *err = NULL;
948 	int resolved_type;
949 
950 	*obj = calloc(1, sizeof(**obj));
951 	if (*obj == NULL)
952 		return got_error_from_errno();
953 
954 	(*obj)->flags = 0;
955 	(*obj)->hdrlen = 0;
956 	(*obj)->size = 0; /* Not known because deltas aren't applied yet. */
957 	memcpy(&(*obj)->id, id, sizeof((*obj)->id));
958 	(*obj)->pack_offset = offset + tslen;
959 
960 	(*obj)->path_packfile = strdup(path_packfile);
961 	if ((*obj)->path_packfile == NULL) {
962 		err = got_error_from_errno();
963 		goto done;
964 	}
965 	(*obj)->flags |= GOT_OBJ_FLAG_PACKED;
966 
967 	SIMPLEQ_INIT(&(*obj)->deltas.entries);
968 	(*obj)->flags |= GOT_OBJ_FLAG_DELTIFIED;
969 
970 	err = resolve_delta_chain(&(*obj)->deltas, repo, fd, packfile_size,
971 	    path_packfile, offset, tslen, delta_type, delta_size,
972 	    GOT_DELTA_CHAIN_RECURSION_MAX);
973 	if (err)
974 		goto done;
975 
976 	err = got_delta_chain_get_base_type(&resolved_type, &(*obj)->deltas);
977 	if (err)
978 		goto done;
979 	(*obj)->type = resolved_type;
980 
981 done:
982 	if (err) {
983 		got_object_close(*obj);
984 		*obj = NULL;
985 	}
986 	return err;
987 }
988 
989 static const struct got_error *
990 open_packed_object(struct got_object **obj, struct got_repository *repo,
991     struct got_packidx *packidx, int idx, struct got_object_id *id)
992 {
993 	const struct got_error *err = NULL;
994 	off_t offset;
995 	char *path_packfile;
996 	struct got_pack *pack;
997 	uint8_t type;
998 	uint64_t size;
999 	size_t tslen;
1000 
1001 	*obj = NULL;
1002 
1003 	offset = get_object_offset(packidx, idx);
1004 	if (offset == (uint64_t)-1)
1005 		return got_error(GOT_ERR_BAD_PACKIDX);
1006 
1007 	err = get_packfile_path(&path_packfile, repo, packidx);
1008 	if (err)
1009 		return err;
1010 
1011 	pack = get_cached_pack(path_packfile, repo);
1012 	if (pack == NULL) {
1013 		err = cache_pack(&pack, path_packfile, packidx, repo);
1014 		if (err)
1015 			goto done;
1016 	}
1017 
1018 	if (offset >= pack->filesize) {
1019 		err = got_error(GOT_ERR_PACK_OFFSET);
1020 		goto done;
1021 	}
1022 	if (lseek(pack->fd, offset, SEEK_SET) == -1) {
1023 		err = got_error_from_errno();
1024 		goto done;
1025 	}
1026 
1027 	err = parse_object_type_and_size(&type, &size, &tslen, pack->fd);
1028 	if (err)
1029 		goto done;
1030 
1031 	switch (type) {
1032 	case GOT_OBJ_TYPE_COMMIT:
1033 	case GOT_OBJ_TYPE_TREE:
1034 	case GOT_OBJ_TYPE_BLOB:
1035 	case GOT_OBJ_TYPE_TAG:
1036 		err = open_plain_object(obj, path_packfile, id, type,
1037 		    offset + tslen, size);
1038 		break;
1039 
1040 	case GOT_OBJ_TYPE_OFFSET_DELTA:
1041 	case GOT_OBJ_TYPE_REF_DELTA:
1042 		err = open_delta_object(obj, repo, path_packfile, pack->fd,
1043 		    pack->filesize, id, offset, tslen, type, size);
1044 		break;
1045 
1046 	default:
1047 		err = got_error(GOT_ERR_OBJ_TYPE);
1048 		goto done;
1049 	}
1050 done:
1051 	free(path_packfile);
1052 	return err;
1053 }
1054 
1055 const struct got_error *
1056 got_packfile_open_object(struct got_object **obj, struct got_object_id *id,
1057     struct got_repository *repo)
1058 {
1059 	const struct got_error *err = NULL;
1060 	struct got_packidx *packidx = NULL;
1061 	int idx;
1062 
1063 	err = search_packidx(&packidx, &idx, repo, id);
1064 	if (err)
1065 		return err;
1066 
1067 	err = open_packed_object(obj, repo, packidx, idx, id);
1068 	if (err)
1069 		return err;
1070 
1071 	err = cache_pack(NULL, (*obj)->path_packfile, packidx, repo);
1072 	return err;
1073 }
1074 
1075 static const struct got_error *
1076 get_delta_chain_max_size(uint64_t *max_size, struct got_delta_chain *deltas)
1077 {
1078 	struct got_delta *delta;
1079 	uint64_t base_size = 0, result_size = 0;
1080 
1081 	*max_size = 0;
1082 	SIMPLEQ_FOREACH(delta, &deltas->entries, entry) {
1083 		/* Plain object types are the delta base. */
1084 		if (delta->type != GOT_OBJ_TYPE_COMMIT &&
1085 		    delta->type != GOT_OBJ_TYPE_TREE &&
1086 		    delta->type != GOT_OBJ_TYPE_BLOB &&
1087 		    delta->type != GOT_OBJ_TYPE_TAG) {
1088 			const struct got_error *err;
1089 			err = got_delta_get_sizes(&base_size, &result_size,
1090 			    delta->delta_buf, delta->delta_len);
1091 			if (err)
1092 				return err;
1093 		} else
1094 			base_size = delta->size;
1095 		if (base_size > *max_size)
1096 			*max_size = base_size;
1097 		if (result_size > *max_size)
1098 			*max_size = result_size;
1099 	}
1100 
1101 	return NULL;
1102 }
1103 
1104 static const struct got_error *
1105 dump_delta_chain_to_file(size_t *result_size, struct got_delta_chain *deltas,
1106     FILE *outfile, struct got_repository *repo)
1107 {
1108 	const struct got_error *err = NULL;
1109 	struct got_delta *delta;
1110 	FILE *base_file = NULL, *accum_file = NULL;
1111 	uint8_t *base_buf = NULL, *accum_buf = NULL;
1112 	size_t accum_size = 0;
1113 	uint64_t max_size;
1114 	int n = 0;
1115 
1116 	*result_size = 0;
1117 
1118 	if (SIMPLEQ_EMPTY(&deltas->entries))
1119 		return got_error(GOT_ERR_BAD_DELTA_CHAIN);
1120 
1121 	/* We process small enough files entirely in memory for speed. */
1122 	err = get_delta_chain_max_size(&max_size, deltas);
1123 	if (err)
1124 		return err;
1125 	if (max_size < GOT_DELTA_RESULT_SIZE_CACHED_MAX) {
1126 		accum_buf = malloc(max_size);
1127 		if (accum_buf == NULL)
1128 			return got_error_from_errno();
1129 	} else {
1130 		base_file = got_opentemp();
1131 		if (base_file == NULL)
1132 			return got_error_from_errno();
1133 
1134 		accum_file = got_opentemp();
1135 		if (accum_file == NULL) {
1136 			err = got_error_from_errno();
1137 			fclose(base_file);
1138 			return err;
1139 		}
1140 	}
1141 
1142 	/* Deltas are ordered in ascending order. */
1143 	SIMPLEQ_FOREACH(delta, &deltas->entries, entry) {
1144 		if (n == 0) {
1145 			struct got_pack *pack;
1146 			size_t base_len;
1147 			off_t delta_data_offset;
1148 
1149 			/* Plain object types are the delta base. */
1150 			if (delta->type != GOT_OBJ_TYPE_COMMIT &&
1151 			    delta->type != GOT_OBJ_TYPE_TREE &&
1152 			    delta->type != GOT_OBJ_TYPE_BLOB &&
1153 			    delta->type != GOT_OBJ_TYPE_TAG) {
1154 				err = got_error(GOT_ERR_BAD_DELTA_CHAIN);
1155 				goto done;
1156 			}
1157 
1158 			pack = get_cached_pack(delta->path_packfile, repo);
1159 			if (pack == NULL) {
1160 				err = got_error(GOT_ERR_BAD_DELTA_CHAIN);
1161 				goto done;
1162 			}
1163 
1164 			delta_data_offset = delta->offset + delta->tslen;
1165 			if (delta_data_offset >= pack->filesize) {
1166 				err = got_error(GOT_ERR_PACK_OFFSET);
1167 				goto done;
1168 			}
1169 			if (lseek(pack->fd, delta_data_offset, SEEK_SET) == -1) {
1170 				err = got_error_from_errno();
1171 				goto done;
1172 			}
1173 			if (base_file)
1174 				err = got_inflate_to_file_fd(&base_len,
1175 				    pack->fd, base_file);
1176 			else {
1177 				err = got_inflate_to_mem_fd(&base_buf,
1178 				    &base_len, pack->fd);
1179 				if (base_len < max_size) {
1180 					uint8_t *p;
1181 					p = reallocarray(base_buf, 1, max_size);
1182 					if (p == NULL) {
1183 						err = got_error_from_errno();
1184 						goto done;
1185 					}
1186 					base_buf = p;
1187 				}
1188 			}
1189 			if (err)
1190 				goto done;
1191 			n++;
1192 			if (base_file)
1193 				rewind(base_file);
1194 			continue;
1195 		}
1196 
1197 		if (base_buf) {
1198 			err = got_delta_apply_in_mem(base_buf, delta->delta_buf,
1199 			    delta->delta_len, accum_buf, &accum_size);
1200 			n++;
1201 		} else {
1202 			err = got_delta_apply(base_file, delta->delta_buf,
1203 			    delta->delta_len,
1204 			    /* Final delta application writes to output file. */
1205 			    ++n < deltas->nentries ? accum_file : outfile,
1206 			    &accum_size);
1207 		}
1208 		if (err)
1209 			goto done;
1210 
1211 		if (n < deltas->nentries) {
1212 			/* Accumulated delta becomes the new base. */
1213 			if (base_buf) {
1214 				uint8_t *tmp = accum_buf;
1215 				accum_buf = base_buf;
1216 				base_buf = tmp;
1217 			} else {
1218 				FILE *tmp = accum_file;
1219 				accum_file = base_file;
1220 				base_file = tmp;
1221 				rewind(base_file);
1222 				rewind(accum_file);
1223 			}
1224 		}
1225 	}
1226 
1227 done:
1228 	free(base_buf);
1229 	if (accum_buf) {
1230 		size_t len = fwrite(accum_buf, 1, accum_size, outfile);
1231 		free(accum_buf);
1232 		if (len != accum_size)
1233 			return got_ferror(outfile, GOT_ERR_IO);
1234 	}
1235 	if (base_file)
1236 		fclose(base_file);
1237 	if (accum_file)
1238 		fclose(accum_file);
1239 	rewind(outfile);
1240 	if (err == NULL)
1241 		*result_size = accum_size;
1242 	return err;
1243 }
1244 
1245 static const struct got_error *
1246 dump_delta_chain_to_mem(uint8_t **outbuf, size_t *outlen,
1247     struct got_delta_chain *deltas, struct got_repository *repo)
1248 {
1249 	const struct got_error *err = NULL;
1250 	struct got_delta *delta;
1251 	uint8_t *base_buf = NULL, *accum_buf = NULL;
1252 	size_t accum_size;
1253 	uint64_t max_size;
1254 	int n = 0;
1255 
1256 	*outbuf = NULL;
1257 	*outlen = 0;
1258 
1259 	if (SIMPLEQ_EMPTY(&deltas->entries))
1260 		return got_error(GOT_ERR_BAD_DELTA_CHAIN);
1261 
1262 	err = get_delta_chain_max_size(&max_size, deltas);
1263 	if (err)
1264 		return err;
1265 	accum_buf = malloc(max_size);
1266 	if (accum_buf == NULL)
1267 		return got_error_from_errno();
1268 
1269 	/* Deltas are ordered in ascending order. */
1270 	SIMPLEQ_FOREACH(delta, &deltas->entries, entry) {
1271 		if (n == 0) {
1272 			struct got_pack *pack;
1273 			size_t base_len;
1274 			size_t delta_data_offset;
1275 
1276 			/* Plain object types are the delta base. */
1277 			if (delta->type != GOT_OBJ_TYPE_COMMIT &&
1278 			    delta->type != GOT_OBJ_TYPE_TREE &&
1279 			    delta->type != GOT_OBJ_TYPE_BLOB &&
1280 			    delta->type != GOT_OBJ_TYPE_TAG) {
1281 				err = got_error(GOT_ERR_BAD_DELTA_CHAIN);
1282 				goto done;
1283 			}
1284 
1285 			pack = get_cached_pack(delta->path_packfile, repo);
1286 			if (pack == NULL) {
1287 				err = got_error(GOT_ERR_BAD_DELTA_CHAIN);
1288 				goto done;
1289 			}
1290 
1291 			delta_data_offset = delta->offset + delta->tslen;
1292 			if (delta_data_offset >= pack->filesize) {
1293 				err = got_error(GOT_ERR_PACK_OFFSET);
1294 				goto done;
1295 			}
1296 			if (lseek(pack->fd, delta_data_offset, SEEK_SET) == -1) {
1297 				err = got_error_from_errno();
1298 				goto done;
1299 			}
1300 			err = got_inflate_to_mem_fd(&base_buf, &base_len,
1301 			    pack->fd);
1302 			if (base_len < max_size) {
1303 				uint8_t *p;
1304 				p = reallocarray(base_buf, 1, max_size);
1305 				if (p == NULL) {
1306 					err = got_error_from_errno();
1307 					goto done;
1308 				}
1309 				base_buf = p;
1310 			}
1311 			if (err)
1312 				goto done;
1313 			n++;
1314 			continue;
1315 		}
1316 
1317 		err = got_delta_apply_in_mem(base_buf, delta->delta_buf,
1318 		    delta->delta_len, accum_buf, &accum_size);
1319 		n++;
1320 		if (err)
1321 			goto done;
1322 
1323 		if (n < deltas->nentries) {
1324 			/* Accumulated delta becomes the new base. */
1325 			uint8_t *tmp = accum_buf;
1326 			accum_buf = base_buf;
1327 			base_buf = tmp;
1328 		}
1329 	}
1330 
1331 done:
1332 	free(base_buf);
1333 	if (err) {
1334 		free(accum_buf);
1335 		*outbuf = NULL;
1336 		*outlen = 0;
1337 	} else {
1338 		*outbuf = accum_buf;
1339 		*outlen = accum_size;
1340 	}
1341 	return err;
1342 }
1343 
1344 const struct got_error *
1345 got_packfile_extract_object(FILE **f, struct got_object *obj,
1346     struct got_repository *repo)
1347 {
1348 	const struct got_error *err = NULL;
1349 
1350 	*f = NULL;
1351 
1352 	if ((obj->flags & GOT_OBJ_FLAG_PACKED) == 0)
1353 		return got_error(GOT_ERR_OBJ_NOT_PACKED);
1354 
1355 	*f = got_opentemp();
1356 	if (*f == NULL) {
1357 		err = got_error_from_errno();
1358 		goto done;
1359 	}
1360 
1361 	if ((obj->flags & GOT_OBJ_FLAG_DELTIFIED) == 0) {
1362 		struct got_pack *pack;
1363 
1364 		pack = get_cached_pack(obj->path_packfile, repo);
1365 		if (pack == NULL) {
1366 			err = cache_pack(&pack, obj->path_packfile, NULL, repo);
1367 			if (err)
1368 				goto done;
1369 		}
1370 
1371 		if (obj->pack_offset >= pack->filesize) {
1372 			err = got_error(GOT_ERR_PACK_OFFSET);
1373 			goto done;
1374 		}
1375 		if (lseek(pack->fd, obj->pack_offset, SEEK_SET) == -1) {
1376 			err = got_error_from_errno();
1377 			goto done;
1378 		}
1379 
1380 		err = got_inflate_to_file_fd(&obj->size, pack->fd, *f);
1381 	} else
1382 		err = dump_delta_chain_to_file(&obj->size,
1383 		    &obj->deltas, *f, repo);
1384 done:
1385 	if (err && *f) {
1386 		fclose(*f);
1387 		*f = NULL;
1388 	}
1389 	return err;
1390 }
1391 
1392 const struct got_error *
1393 got_packfile_extract_object_to_mem(uint8_t **buf, size_t *len,
1394     struct got_object *obj, struct got_repository *repo)
1395 {
1396 	const struct got_error *err = NULL;
1397 
1398 	if ((obj->flags & GOT_OBJ_FLAG_PACKED) == 0)
1399 		return got_error(GOT_ERR_OBJ_NOT_PACKED);
1400 
1401 	if ((obj->flags & GOT_OBJ_FLAG_DELTIFIED) == 0) {
1402 		struct got_pack *pack;
1403 
1404 		pack = get_cached_pack(obj->path_packfile, repo);
1405 		if (pack == NULL) {
1406 			err = cache_pack(&pack, obj->path_packfile, NULL, repo);
1407 			if (err)
1408 				goto done;
1409 		}
1410 
1411 		if (obj->pack_offset >= pack->filesize) {
1412 			err = got_error(GOT_ERR_PACK_OFFSET);
1413 			goto done;
1414 		}
1415 		if (lseek(pack->fd, obj->pack_offset, SEEK_SET) == -1) {
1416 			err = got_error_from_errno();
1417 			goto done;
1418 		}
1419 
1420 		err = got_inflate_to_mem_fd(buf, len, pack->fd);
1421 	} else
1422 		err = dump_delta_chain_to_mem(buf, len, &obj->deltas, repo);
1423 done:
1424 	return err;
1425 }