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Date:: Mon Apr 2 08:09:22 2018 UTC
Message:: in get_packfile_size(), get errno from stat() and init output early
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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 
37 #include "got_lib_sha1.h"
38 #include "got_lib_pack.h"
39 #include "got_lib_path.h"
40 #include "got_lib_delta.h"
41 #include "got_lib_zbuf.h"
42 #include "got_lib_object.h"
43 #include "got_lib_repository.h"
44 
45 #ifndef nitems
46 #define nitems(_a) (sizeof(_a) / sizeof((_a)[0]))
47 #endif
48 
49 #define GOT_PACK_PREFIX		"pack-"
50 #define GOT_PACKFILE_SUFFIX	".pack"
51 #define GOT_PACKIDX_SUFFIX		".idx"
52 #define GOT_PACKFILE_NAMELEN	(strlen(GOT_PACK_PREFIX) + \
53 				SHA1_DIGEST_STRING_LENGTH - 1 + \
54 				strlen(GOT_PACKFILE_SUFFIX))
55 #define GOT_PACKIDX_NAMELEN	(strlen(GOT_PACK_PREFIX) + \
56 				SHA1_DIGEST_STRING_LENGTH - 1 + \
57 				strlen(GOT_PACKIDX_SUFFIX))
58 
59 #ifndef MIN
60 #define	MIN(_a,_b) ((_a) < (_b) ? (_a) : (_b))
61 #endif
62 
63 static const struct got_error *
64 verify_fanout_table(uint32_t *fanout_table)
65 {
66 	int i;
67 
68 	for (i = 0; i < 0xff - 1; i++) {
69 		if (be32toh(fanout_table[i]) > be32toh(fanout_table[i + 1]))
70 			return got_error(GOT_ERR_BAD_PACKIDX);
71 	}
72 
73 	return NULL;
74 }
75 
76 static const struct got_error *
77 get_packfile_size(size_t *size, const char *path)
78 {
79 	struct stat sb;
80 	char *dot;
81 
82 	*size = 0;
83 
84 	dot = strrchr(path, '.');
85 	if (dot == NULL)
86 		return got_error(GOT_ERR_BAD_PATH);
87 
88 	/* Path must point to a pack index or to a pack file. */
89 	if (strcmp(dot, ".idx") == 0) {
90 		const struct got_error *err = NULL;
91 		char *path_pack;
92 		char base_path[PATH_MAX];
93 
94 		/* Convert pack index path to pack file path. */
95 		if (strlcpy(base_path, path, PATH_MAX) > PATH_MAX)
96 			return got_error(GOT_ERR_NO_SPACE);
97 		dot = strrchr(base_path, '.');
98 		if (dot == NULL)
99 			return got_error(GOT_ERR_BAD_PATH);
100 		*dot = '\0';
101 		if (asprintf(&path_pack, "%s.pack", base_path) == -1)
102 			return got_error_from_errno();
103 
104 		if (stat(path_pack, &sb) != 0)
105 			err = got_error_from_errno();
106 		free(path_pack);
107 		if (err)
108 			return err;
109 	} else if (strcmp(dot, ".pack") == 0) {
110 		if (stat(path, &sb) != 0)
111 			return got_error_from_errno();
112 	} else
113 		return got_error(GOT_ERR_BAD_PATH);
114 
115 	*size = sb.st_size;
116 	return 0;
117 }
118 
119 const struct got_error *
120 got_packidx_open(struct got_packidx_v2_hdr **packidx, const char *path)
121 {
122 	struct got_packidx_v2_hdr *p;
123 	FILE *f;
124 	const struct got_error *err = NULL;
125 	size_t n, nobj, packfile_size;
126 	SHA1_CTX ctx;
127 	uint8_t sha1[SHA1_DIGEST_LENGTH];
128 
129 	SHA1Init(&ctx);
130 
131 	f = fopen(path, "rb");
132 	if (f == NULL)
133 		return got_error_from_errno();
134 
135 	err = get_packfile_size(&packfile_size, path);
136 	if (err)
137 		return err;
138 
139 	p = calloc(1, sizeof(*p));
140 	if (p == NULL) {
141 		err = got_error_from_errno();
142 		goto done;
143 	}
144 
145 	n = fread(&p->magic, sizeof(p->magic), 1, f);
146 	if (n != 1) {
147 		err = got_ferror(f, GOT_ERR_BAD_PACKIDX);
148 		goto done;
149 	}
150 
151 	if (betoh32(p->magic) != GOT_PACKIDX_V2_MAGIC) {
152 		err = got_error(GOT_ERR_BAD_PACKIDX);
153 		goto done;
154 	}
155 
156 	SHA1Update(&ctx, (uint8_t *)&p->magic, sizeof(p->magic));
157 
158 	n = fread(&p->version, sizeof(p->version), 1, f);
159 	if (n != 1) {
160 		err = got_ferror(f, GOT_ERR_BAD_PACKIDX);
161 		goto done;
162 	}
163 
164 	if (betoh32(p->version) != GOT_PACKIDX_VERSION) {
165 		err = got_error(GOT_ERR_BAD_PACKIDX);
166 		goto done;
167 	}
168 
169 	SHA1Update(&ctx, (uint8_t *)&p->version, sizeof(p->version));
170 
171 	n = fread(&p->fanout_table, sizeof(p->fanout_table), 1, f);
172 	if (n != 1) {
173 		err = got_ferror(f, GOT_ERR_BAD_PACKIDX);
174 		goto done;
175 	}
176 
177 	err = verify_fanout_table(p->fanout_table);
178 	if (err)
179 		goto done;
180 
181 	SHA1Update(&ctx, (uint8_t *)p->fanout_table, sizeof(p->fanout_table));
182 
183 	nobj = betoh32(p->fanout_table[0xff]);
184 
185 	p->sorted_ids = calloc(nobj, sizeof(*p->sorted_ids));
186 	if (p->sorted_ids == NULL) {
187 		err = got_error_from_errno();
188 		goto done;
189 	}
190 
191 	n = fread(p->sorted_ids, sizeof(*p->sorted_ids), nobj, f);
192 	if (n != nobj) {
193 		err = got_ferror(f, GOT_ERR_BAD_PACKIDX);
194 		goto done;
195 	}
196 
197 	SHA1Update(&ctx, (uint8_t *)p->sorted_ids,
198 	    nobj * sizeof(*p->sorted_ids));
199 
200 	p->crc32 = calloc(nobj, sizeof(*p->crc32));
201 	if (p->crc32 == NULL) {
202 		err = got_error_from_errno();
203 		goto done;
204 	}
205 
206 	n = fread(p->crc32, sizeof(*p->crc32), nobj, f);
207 	if (n != nobj) {
208 		err = got_ferror(f, GOT_ERR_BAD_PACKIDX);
209 		goto done;
210 	}
211 
212 	SHA1Update(&ctx, (uint8_t *)p->crc32, nobj * sizeof(*p->crc32));
213 
214 	p->offsets = calloc(nobj, sizeof(*p->offsets));
215 	if (p->offsets == NULL) {
216 		err = got_error_from_errno();
217 		goto done;
218 	}
219 
220 	n = fread(p->offsets, sizeof(*p->offsets), nobj, f);
221 	if (n != nobj) {
222 		err = got_ferror(f, GOT_ERR_BAD_PACKIDX);
223 		goto done;
224 	}
225 
226 	SHA1Update(&ctx, (uint8_t *)p->offsets, nobj * sizeof(*p->offsets));
227 
228 	/* Large file offsets are contained only in files > 2GB. */
229 	if (packfile_size <= 0x80000000)
230 		goto checksum;
231 
232 	p->large_offsets = calloc(nobj, sizeof(*p->large_offsets));
233 	if (p->large_offsets == NULL) {
234 		err = got_error_from_errno();
235 		goto done;
236 	}
237 
238 	n = fread(p->large_offsets, sizeof(*p->large_offsets), nobj, f);
239 	if (n != nobj) {
240 		err = got_ferror(f, GOT_ERR_BAD_PACKIDX);
241 		goto done;
242 	}
243 
244 	SHA1Update(&ctx, (uint8_t*)p->large_offsets,
245 	    nobj * sizeof(*p->large_offsets));
246 
247 checksum:
248 	n = fread(&p->trailer, sizeof(p->trailer), 1, f);
249 	if (n != 1) {
250 		err = got_ferror(f, GOT_ERR_BAD_PACKIDX);
251 		goto done;
252 	}
253 
254 	SHA1Update(&ctx, p->trailer.packfile_sha1, SHA1_DIGEST_LENGTH);
255 	SHA1Final(sha1, &ctx);
256 	if (memcmp(p->trailer.packidx_sha1, sha1, SHA1_DIGEST_LENGTH) != 0)
257 		err = got_error(GOT_ERR_PACKIDX_CSUM);
258 done:
259 	fclose(f);
260 	if (err)
261 		got_packidx_close(p);
262 	else
263 		*packidx = p;
264 	return err;
265 }
266 
267 void
268 got_packidx_close(struct got_packidx_v2_hdr *packidx)
269 {
270 	free(packidx->sorted_ids);
271 	free(packidx->offsets);
272 	free(packidx->crc32);
273 	free(packidx->large_offsets);
274 	free(packidx);
275 }
276 
277 static int
278 is_packidx_filename(const char *name, size_t len)
279 {
280 	if (len != GOT_PACKIDX_NAMELEN)
281 		return 0;
282 
283 	if (strncmp(name, GOT_PACK_PREFIX, strlen(GOT_PACK_PREFIX)) != 0)
284 		return 0;
285 
286 	if (strcmp(name + strlen(GOT_PACK_PREFIX) +
287 	    SHA1_DIGEST_STRING_LENGTH - 1, GOT_PACKIDX_SUFFIX) != 0)
288 		return 0;
289 
290 	return 1;
291 }
292 
293 static off_t
294 get_object_offset(struct got_packidx_v2_hdr *packidx, int idx)
295 {
296 	uint32_t totobj = betoh32(packidx->fanout_table[0xff]);
297 	uint32_t offset = betoh32(packidx->offsets[idx]);
298 	if (offset & GOT_PACKIDX_OFFSET_VAL_IS_LARGE_IDX) {
299 		uint64_t loffset;
300 		idx = offset & GOT_PACKIDX_OFFSET_VAL_MASK;
301 		if (idx < 0 || idx > totobj || packidx->large_offsets == NULL)
302 			return -1;
303 		loffset = betoh64(packidx->large_offsets[idx]);
304 		return (loffset > INT64_MAX ? -1 : (off_t)loffset);
305 	}
306 	return (off_t)(offset & GOT_PACKIDX_OFFSET_VAL_MASK);
307 }
308 
309 static const struct got_error *
310 get_packfile_path(char **path_packfile, struct got_repository *repo,
311     struct got_packidx_v2_hdr *packidx);
312 
313 static int
314 get_object_idx(struct got_packidx_v2_hdr *packidx, struct got_object_id *id, struct got_repository *repo)
315 {
316 	u_int8_t id0 = id->sha1[0];
317 	uint32_t totobj = betoh32(packidx->fanout_table[0xff]);
318 	int i = 0;
319 
320 	if (id0 > 0)
321 		i = betoh32(packidx->fanout_table[id0 - 1]);
322 
323 	while (i < totobj) {
324 		struct got_object_id *oid = &packidx->sorted_ids[i];
325 		int cmp = got_object_id_cmp(id, oid);
326 
327 		if (cmp == 0)
328 			return i;
329 		i++;
330 	}
331 
332 	return -1;
333 }
334 
335 static struct got_packidx_v2_hdr *
336 dup_packidx(struct got_packidx_v2_hdr *packidx)
337 {
338 	struct got_packidx_v2_hdr *p;
339 	size_t nobj;
340 
341 	p = calloc(1, sizeof(*p));
342 	if (p == NULL)
343 		return NULL;
344 
345 	memcpy(p, packidx, sizeof(*p));
346 	p->sorted_ids = NULL;
347 	p->crc32 = NULL;
348 	p->offsets = NULL;
349 	p->large_offsets = NULL;
350 
351 	nobj = betoh32(p->fanout_table[0xff]);
352 
353 	p->sorted_ids = calloc(nobj, sizeof(*p->sorted_ids));
354 	if (p->sorted_ids == NULL)
355 		goto err;
356 	memcpy(p->sorted_ids, packidx->sorted_ids, nobj * sizeof(*p->sorted_ids));
357 
358 	p->crc32 = calloc(nobj, sizeof(*p->crc32));
359 	if (p->crc32 == NULL)
360 		goto err;
361 	memcpy(p->crc32, packidx->crc32, nobj * sizeof(*p->crc32));
362 
363 	p->offsets = calloc(nobj, sizeof(*p->offsets));
364 	if (p->offsets == NULL)
365 		goto err;
366 	memcpy(p->offsets, packidx->offsets, nobj * sizeof(*p->offsets));
367 
368 	if (p->large_offsets) {
369 		p->large_offsets = calloc(nobj, sizeof(*p->large_offsets));
370 		if (p->large_offsets == NULL)
371 			goto err;
372 		memcpy(p->large_offsets, packidx->large_offsets,
373 		    nobj * sizeof(*p->large_offsets));
374 	}
375 
376 	return p;
377 
378 err:
379 	free(p->large_offsets);
380 	free(p->offsets);
381 	free(p->crc32);
382 	free(p->sorted_ids);
383 	free(p);
384 	return NULL;
385 }
386 
387 static void
388 cache_packidx(struct got_packidx_v2_hdr *packidx, struct got_repository *repo)
389 {
390 	int i;
391 
392 	for (i = 0; i < nitems(repo->packidx_cache); i++) {
393 		if (repo->packidx_cache[i] == NULL)
394 			break;
395 	}
396 
397 	if (i == nitems(repo->packidx_cache)) {
398 		got_packidx_close(repo->packidx_cache[i - 1]);
399 		memmove(&repo->packidx_cache[1], &repo->packidx_cache[0],
400 		    sizeof(repo->packidx_cache) -
401 		    sizeof(repo->packidx_cache[0]));
402 		i = 0;
403 	}
404 
405 	repo->packidx_cache[i] = dup_packidx(packidx);
406 }
407 
408 static const struct got_error *
409 search_packidx(struct got_packidx_v2_hdr **packidx, int *idx,
410     struct got_repository *repo, struct got_object_id *id)
411 {
412 	const struct got_error *err;
413 	char *path_packdir;
414 	DIR *packdir;
415 	struct dirent *dent;
416 	char *path_packidx;
417 	int i;
418 
419 	/* Search pack index cache. */
420 	for (i = 0; i < nitems(repo->packidx_cache); i++) {
421 		if (repo->packidx_cache[i] == NULL)
422 			break;
423 		*idx = get_object_idx(repo->packidx_cache[i], id, repo);
424 		if (*idx != -1) {
425 			*packidx = repo->packidx_cache[i];
426 			return NULL;
427 		}
428 	}
429 	/* No luck. Search the filesystem. */
430 
431 	path_packdir = got_repo_get_path_objects_pack(repo);
432 	if (path_packdir == NULL)
433 		return got_error_from_errno();
434 
435 	packdir = opendir(path_packdir);
436 	if (packdir == NULL) {
437 		err = got_error_from_errno();
438 		goto done;
439 	}
440 
441 	while ((dent = readdir(packdir)) != NULL) {
442 		if (!is_packidx_filename(dent->d_name, dent->d_namlen))
443 			continue;
444 
445 		if (asprintf(&path_packidx, "%s/%s", path_packdir,
446 		    dent->d_name) == -1) {
447 			err = got_error_from_errno();
448 			goto done;
449 		}
450 
451 		err = got_packidx_open(packidx, path_packidx);
452 		free(path_packidx);
453 		if (err)
454 			goto done;
455 
456 		*idx = get_object_idx(*packidx, id, repo);
457 		if (*idx != -1) {
458 			err = NULL; /* found the object */
459 			cache_packidx(*packidx, repo);
460 			goto done;
461 		}
462 
463 		got_packidx_close(*packidx);
464 		*packidx = NULL;
465 	}
466 
467 	err = got_error(GOT_ERR_NO_OBJ);
468 done:
469 	free(path_packdir);
470 	if (packdir && closedir(packdir) != 0 && err == 0)
471 		err = got_error_from_errno();
472 	return err;
473 }
474 
475 static const struct got_error *
476 get_packfile_path(char **path_packfile, struct got_repository *repo,
477     struct got_packidx_v2_hdr *packidx)
478 {
479 	char *path_packdir;
480 	char hex[SHA1_DIGEST_STRING_LENGTH];
481 	char *sha1str;
482 
483 	path_packdir = got_repo_get_path_objects_pack(repo);
484 	if (path_packdir == NULL)
485 		return got_error_from_errno();
486 
487 	sha1str = got_sha1_digest_to_str(packidx->trailer.packfile_sha1,
488 	    hex, sizeof(hex));
489 	if (sha1str == NULL)
490 		return got_error(GOT_ERR_PACKIDX_CSUM);
491 
492 	if (asprintf(path_packfile, "%s/%s%s%s", path_packdir,
493 	    GOT_PACK_PREFIX, sha1str, GOT_PACKFILE_SUFFIX) == -1) {
494 		*path_packfile = NULL;
495 		return got_error_from_errno();
496 	}
497 
498 	return NULL;
499 }
500 
501 const struct got_error *
502 read_packfile_hdr(FILE *f, struct got_packidx_v2_hdr *packidx)
503 {
504 	const struct got_error *err = NULL;
505 	uint32_t totobj = betoh32(packidx->fanout_table[0xff]);
506 	struct got_packfile_hdr hdr;
507 	size_t n;
508 
509 	n = fread(&hdr, sizeof(hdr), 1, f);
510 	if (n != 1)
511 		return got_ferror(f, GOT_ERR_BAD_PACKIDX);
512 
513 	if (betoh32(hdr.signature) != GOT_PACKFILE_SIGNATURE ||
514 	    betoh32(hdr.version) != GOT_PACKFILE_VERSION ||
515 	    betoh32(hdr.nobjects) != totobj)
516 		err = got_error(GOT_ERR_BAD_PACKFILE);
517 
518 	return err;
519 }
520 
521 static const struct got_error *
522 open_packfile(FILE **packfile, const char *path_packfile,
523     struct got_repository *repo, struct got_packidx_v2_hdr *packidx)
524 {
525 	const struct got_error *err = NULL;
526 
527 	*packfile = NULL;
528 
529 	*packfile = fopen(path_packfile, "rb");
530 	if (*packfile == NULL) {
531 		err = got_error_from_errno();
532 		return err;
533 	}
534 
535 	if (packidx) {
536 		err = read_packfile_hdr(*packfile, packidx);
537 		if (err) {
538 			fclose(*packfile);
539 			*packfile = NULL;
540 		}
541 	}
542 	return err;
543 }
544 
545 void
546 got_pack_close(struct got_pack *pack)
547 {
548 	fclose(pack->packfile);
549 	pack->packfile = NULL;
550 	free(pack->path_packfile);
551 	pack->path_packfile = NULL;
552 	pack->filesize = 0;
553 }
554 
555 static const struct got_error *
556 cache_pack(struct got_pack **packp, const char *path_packfile,
557     struct got_packidx_v2_hdr *packidx, struct got_repository *repo)
558 {
559 	const struct got_error *err = NULL;
560 	struct got_pack *pack = NULL;
561 	int i;
562 
563 	if (packp)
564 		*packp = NULL;
565 
566 	for (i = 0; i < nitems(repo->packs); i++) {
567 		pack = &repo->packs[i];
568 		if (pack->path_packfile == NULL)
569 			break;
570 		if (strcmp(pack->path_packfile, path_packfile) == 0)
571 			return NULL;
572 	}
573 
574 	if (i == nitems(repo->packs) - 1) {
575 		got_pack_close(&repo->packs[i - 1]);
576 		memmove(&repo->packs[1], &repo->packs[0],
577 		    sizeof(repo->packs) - sizeof(repo->packs[0]));
578 		i = 0;
579 	}
580 
581 	pack = &repo->packs[i];
582 
583 	pack->path_packfile = strdup(path_packfile);
584 	if (pack->path_packfile == NULL) {
585 		err = got_error_from_errno();
586 		goto done;
587 	}
588 
589 	err = open_packfile(&pack->packfile, path_packfile, repo, packidx);
590 	if (err)
591 		goto done;
592 
593 	err = get_packfile_size(&pack->filesize, path_packfile);
594 done:
595 	if (err) {
596 		if (pack)
597 			free(pack->path_packfile);
598 		free(pack);
599 	} else if (packp)
600 		*packp = pack;
601 	return err;
602 }
603 
604 struct got_pack *
605 get_cached_pack(const char *path_packfile, struct got_repository *repo)
606 {
607 	struct got_pack *pack = NULL;
608 	int i;
609 
610 	for (i = 0; i < nitems(repo->packs); i++) {
611 		pack = &repo->packs[i];
612 		if (pack->path_packfile == NULL)
613 			break;
614 		if (strcmp(pack->path_packfile, path_packfile) == 0)
615 			return pack;
616 	}
617 
618 	return NULL;
619 }
620 
621 static const struct got_error *
622 parse_object_type_and_size(uint8_t *type, uint64_t *size, size_t *len,
623     FILE *packfile)
624 {
625 	uint8_t t = 0;
626 	uint64_t s = 0;
627 	uint8_t sizeN;
628 	size_t n;
629 	int i = 0;
630 
631 	do {
632 		/* We do not support size values which don't fit in 64 bit. */
633 		if (i > 9)
634 			return got_error(GOT_ERR_NO_SPACE);
635 
636 		n = fread(&sizeN, sizeof(sizeN), 1, packfile);
637 		if (n != 1)
638 			return got_ferror(packfile, GOT_ERR_BAD_PACKIDX);
639 
640 		if (i == 0) {
641 			t = (sizeN & GOT_PACK_OBJ_SIZE0_TYPE_MASK) >>
642 			    GOT_PACK_OBJ_SIZE0_TYPE_MASK_SHIFT;
643 			s = (sizeN & GOT_PACK_OBJ_SIZE0_VAL_MASK);
644 		} else {
645 			size_t shift = 4 + 7 * (i - 1);
646 			s |= ((sizeN & GOT_PACK_OBJ_SIZE_VAL_MASK) << shift);
647 		}
648 		i++;
649 	} while (sizeN & GOT_PACK_OBJ_SIZE_MORE);
650 
651 	*type = t;
652 	*size = s;
653 	*len = i * sizeof(sizeN);
654 	return NULL;
655 }
656 
657 static const struct got_error *
658 open_plain_object(struct got_object **obj, const char *path_packfile,
659     struct got_object_id *id, uint8_t type, off_t offset, size_t size)
660 {
661 	*obj = calloc(1, sizeof(**obj));
662 	if (*obj == NULL)
663 		return got_error_from_errno();
664 
665 	(*obj)->path_packfile = strdup(path_packfile);
666 	if ((*obj)->path_packfile == NULL) {
667 		const struct got_error *err = got_error_from_errno();
668 		free(*obj);
669 		*obj = NULL;
670 		return err;
671 	}
672 
673 	(*obj)->type = type;
674 	(*obj)->flags = GOT_OBJ_FLAG_PACKED;
675 	(*obj)->hdrlen = 0;
676 	(*obj)->size = size;
677 	memcpy(&(*obj)->id, id, sizeof((*obj)->id));
678 	(*obj)->pack_offset = offset;
679 
680 	return NULL;
681 }
682 
683 static const struct got_error *
684 parse_negative_offset(int64_t *offset, size_t *len, FILE *packfile)
685 {
686 	int64_t o = 0;
687 	uint8_t offN;
688 	size_t n;
689 	int i = 0;
690 
691 	do {
692 		/* We do not support offset values which don't fit in 64 bit. */
693 		if (i > 8)
694 			return got_error(GOT_ERR_NO_SPACE);
695 
696 		n = fread(&offN, sizeof(offN), 1, packfile);
697 		if (n != 1)
698 			return got_ferror(packfile, GOT_ERR_BAD_PACKIDX);
699 
700 		if (i == 0)
701 			o = (offN & GOT_PACK_OBJ_DELTA_OFF_VAL_MASK);
702 		else {
703 			o++;
704 			o <<= 7;
705 			o += (offN & GOT_PACK_OBJ_DELTA_OFF_VAL_MASK);
706 		}
707 		i++;
708 	} while (offN & GOT_PACK_OBJ_DELTA_OFF_MORE);
709 
710 	*offset = o;
711 	*len = i * sizeof(offN);
712 	return NULL;
713 }
714 
715 static const struct got_error *
716 parse_offset_delta(off_t *base_offset, FILE *packfile, off_t offset)
717 {
718 	const struct got_error *err;
719 	int64_t negoffset;
720 	size_t negofflen;
721 
722 	err = parse_negative_offset(&negoffset, &negofflen, packfile);
723 	if (err)
724 		return err;
725 
726 	/* Compute the base object's offset (must be in the same pack file). */
727 	*base_offset = (offset - negoffset);
728 	if (*base_offset <= 0)
729 		return got_error(GOT_ERR_BAD_PACKFILE);
730 
731 	return NULL;
732 }
733 
734 static const struct got_error *
735 resolve_delta_chain(struct got_delta_chain *, struct got_repository *,
736     FILE *, const char *, off_t, size_t, int, size_t);
737 
738 static const struct got_error *
739 add_delta(struct got_delta_chain *deltas, const char *path_packfile,
740     off_t delta_offset, size_t tslen, int delta_type, size_t delta_size,
741     size_t delta_data_offset, uint8_t *delta_buf, size_t delta_len)
742 {
743 	struct got_delta *delta;
744 
745 	delta = got_delta_open(path_packfile, delta_offset, tslen,
746 	    delta_type, delta_size, delta_data_offset, delta_buf,
747 	    delta_len);
748 	if (delta == NULL)
749 		return got_error_from_errno();
750 	/* delta is freed in got_object_close() */
751 	deltas->nentries++;
752 	SIMPLEQ_INSERT_HEAD(&deltas->entries, delta, entry);
753 	return NULL;
754 }
755 
756 static const struct got_error *
757 resolve_offset_delta(struct got_delta_chain *deltas,
758     struct got_repository *repo, FILE *packfile, const char *path_packfile,
759     off_t delta_offset,size_t tslen, int delta_type, size_t delta_size)
760 
761 {
762 	const struct got_error *err;
763 	off_t base_offset;
764 	uint8_t base_type;
765 	uint64_t base_size;
766 	size_t base_tslen;
767 	off_t delta_data_offset;
768 	uint8_t *delta_buf;
769 	size_t delta_len;
770 
771 	err = parse_offset_delta(&base_offset, packfile, delta_offset);
772 	if (err)
773 		return err;
774 
775 	delta_data_offset = ftello(packfile);
776 	if (delta_data_offset == -1)
777 		return got_error_from_errno();
778 
779 	err = got_inflate_to_mem(&delta_buf, &delta_len, packfile);
780 	if (err)
781 		return err;
782 
783 	err = add_delta(deltas, path_packfile, delta_offset, tslen,
784 	    delta_type, delta_size, delta_data_offset, delta_buf, delta_len);
785 	if (err)
786 		return err;
787 
788 	/* An offset delta must be in the same packfile. */
789 	if (fseeko(packfile, base_offset, SEEK_SET) != 0)
790 		return got_error_from_errno();
791 
792 	err = parse_object_type_and_size(&base_type, &base_size, &base_tslen,
793 	    packfile);
794 	if (err)
795 		return err;
796 
797 	return resolve_delta_chain(deltas, repo, packfile, path_packfile,
798 	    base_offset, base_tslen, base_type, base_size);
799 }
800 
801 static const struct got_error *
802 resolve_ref_delta(struct got_delta_chain *deltas, struct got_repository *repo,
803     FILE *packfile, const char *path_packfile, off_t delta_offset,
804     size_t tslen, int delta_type, size_t delta_size)
805 {
806 	const struct got_error *err;
807 	struct got_object_id id;
808 	struct got_packidx_v2_hdr *packidx;
809 	int idx;
810 	off_t base_offset;
811 	uint8_t base_type;
812 	uint64_t base_size;
813 	size_t base_tslen;
814 	size_t n;
815 	char *path_base_packfile;
816 	struct got_pack *base_pack;
817 	off_t delta_data_offset;
818 	uint8_t *delta_buf;
819 	size_t delta_len;
820 
821 	n = fread(&id, sizeof(id), 1, packfile);
822 	if (n != 1)
823 		return got_ferror(packfile, GOT_ERR_IO);
824 
825 	delta_data_offset = ftello(packfile);
826 	if (delta_data_offset == -1)
827 		return got_error_from_errno();
828 
829 	err = got_inflate_to_mem(&delta_buf, &delta_len, packfile);
830 	if (err)
831 		return err;
832 
833 	err = add_delta(deltas, path_packfile, delta_offset, tslen,
834 	    delta_type, delta_size, delta_data_offset, delta_buf, delta_len);
835 	if (err)
836 		return err;
837 
838 	err = search_packidx(&packidx, &idx, repo, &id);
839 	if (err)
840 		return err;
841 
842 	base_offset = get_object_offset(packidx, idx);
843 	if (base_offset == (uint64_t)-1) {
844 		return got_error(GOT_ERR_BAD_PACKIDX);
845 	}
846 
847 	err = get_packfile_path(&path_base_packfile, repo, packidx);
848 	if (err)
849 		return err;
850 
851 	base_pack = get_cached_pack(path_base_packfile, repo);
852 	if (base_pack == NULL) {
853 		err = cache_pack(&base_pack, path_base_packfile, NULL, repo);
854 		if (err)
855 			goto done;
856 	}
857 
858 	if (fseeko(base_pack->packfile, base_offset, SEEK_SET) != 0) {
859 		err = got_error_from_errno();
860 		goto done;
861 	}
862 
863 	err = parse_object_type_and_size(&base_type, &base_size, &base_tslen,
864 	    base_pack->packfile);
865 	if (err)
866 		goto done;
867 
868 	err = resolve_delta_chain(deltas, repo, base_pack->packfile,
869 	    path_base_packfile, base_offset, base_tslen, base_type,
870 	    base_size);
871 done:
872 	free(path_base_packfile);
873 	return err;
874 }
875 
876 static const struct got_error *
877 resolve_delta_chain(struct got_delta_chain *deltas, struct got_repository *repo,
878     FILE *packfile, const char *path_packfile, off_t delta_offset, size_t tslen,
879     int delta_type, size_t delta_size)
880 {
881 	const struct got_error *err = NULL;
882 
883 	switch (delta_type) {
884 	case GOT_OBJ_TYPE_COMMIT:
885 	case GOT_OBJ_TYPE_TREE:
886 	case GOT_OBJ_TYPE_BLOB:
887 	case GOT_OBJ_TYPE_TAG:
888 		/* Plain types are the final delta base. Recursion ends. */
889 		err = add_delta(deltas, path_packfile, delta_offset, tslen,
890 		    delta_type, delta_size, 0, NULL, 0);
891 		break;
892 	case GOT_OBJ_TYPE_OFFSET_DELTA:
893 		err = resolve_offset_delta(deltas, repo, packfile,
894 		    path_packfile, delta_offset, tslen, delta_type,
895 		    delta_size);
896 		break;
897 	case GOT_OBJ_TYPE_REF_DELTA:
898 		err = resolve_ref_delta(deltas, repo, packfile,
899 		    path_packfile, delta_offset, tslen, delta_type,
900 		    delta_size);
901 		break;
902 	default:
903 		return got_error(GOT_ERR_OBJ_TYPE);
904 	}
905 
906 	return err;
907 }
908 
909 static const struct got_error *
910 open_delta_object(struct got_object **obj, struct got_repository *repo,
911     struct got_packidx_v2_hdr *packidx, const char *path_packfile,
912     FILE *packfile, struct got_object_id *id, off_t offset, size_t tslen,
913     int delta_type, size_t delta_size)
914 {
915 	const struct got_error *err = NULL;
916 	int resolved_type;
917 
918 	*obj = calloc(1, sizeof(**obj));
919 	if (*obj == NULL)
920 		return got_error_from_errno();
921 
922 	(*obj)->flags = 0;
923 	(*obj)->hdrlen = 0;
924 	(*obj)->size = 0; /* Not known because deltas aren't applied yet. */
925 	memcpy(&(*obj)->id, id, sizeof((*obj)->id));
926 	(*obj)->pack_offset = offset + tslen;
927 
928 	(*obj)->path_packfile = strdup(path_packfile);
929 	if ((*obj)->path_packfile == NULL) {
930 		err = got_error_from_errno();
931 		goto done;
932 	}
933 	(*obj)->flags |= GOT_OBJ_FLAG_PACKED;
934 
935 	SIMPLEQ_INIT(&(*obj)->deltas.entries);
936 	(*obj)->flags |= GOT_OBJ_FLAG_DELTIFIED;
937 
938 	err = resolve_delta_chain(&(*obj)->deltas, repo, packfile,
939 	    path_packfile, offset, tslen, delta_type, delta_size);
940 	if (err)
941 		goto done;
942 
943 	err = got_delta_chain_get_base_type(&resolved_type, &(*obj)->deltas);
944 	if (err)
945 		goto done;
946 	(*obj)->type = resolved_type;
947 
948 done:
949 	if (err) {
950 		got_object_close(*obj);
951 		*obj = NULL;
952 	}
953 	return err;
954 }
955 
956 static const struct got_error *
957 open_packed_object(struct got_object **obj, struct got_repository *repo,
958     struct got_packidx_v2_hdr *packidx, int idx, struct got_object_id *id)
959 {
960 	const struct got_error *err = NULL;
961 	off_t offset;
962 	char *path_packfile;
963 	struct got_pack *pack;
964 	uint8_t type;
965 	uint64_t size;
966 	size_t tslen;
967 
968 	*obj = NULL;
969 
970 	offset = get_object_offset(packidx, idx);
971 	if (offset == (uint64_t)-1)
972 		return got_error(GOT_ERR_BAD_PACKIDX);
973 
974 	err = get_packfile_path(&path_packfile, repo, packidx);
975 	if (err)
976 		return err;
977 
978 	pack = get_cached_pack(path_packfile, repo);
979 	if (pack == NULL) {
980 		err = cache_pack(&pack, path_packfile, packidx, repo);
981 		if (err)
982 			goto done;
983 	}
984 
985 	if (fseeko(pack->packfile, offset, SEEK_SET) != 0) {
986 		err = got_error_from_errno();
987 		goto done;
988 	}
989 
990 	err = parse_object_type_and_size(&type, &size, &tslen, pack->packfile);
991 	if (err)
992 		goto done;
993 
994 	switch (type) {
995 	case GOT_OBJ_TYPE_COMMIT:
996 	case GOT_OBJ_TYPE_TREE:
997 	case GOT_OBJ_TYPE_BLOB:
998 	case GOT_OBJ_TYPE_TAG:
999 		err = open_plain_object(obj, path_packfile, id, type,
1000 		    offset + tslen, size);
1001 		break;
1002 
1003 	case GOT_OBJ_TYPE_OFFSET_DELTA:
1004 	case GOT_OBJ_TYPE_REF_DELTA:
1005 		err = open_delta_object(obj, repo, packidx, path_packfile,
1006 		    pack->packfile, id, offset, tslen, type, size);
1007 		break;
1008 
1009 	default:
1010 		err = got_error(GOT_ERR_OBJ_TYPE);
1011 		goto done;
1012 	}
1013 done:
1014 	free(path_packfile);
1015 	return err;
1016 }
1017 
1018 const struct got_error *
1019 got_packfile_open_object(struct got_object **obj, struct got_object_id *id,
1020     struct got_repository *repo)
1021 {
1022 	const struct got_error *err = NULL;
1023 	struct got_packidx_v2_hdr *packidx = NULL;
1024 	int idx;
1025 
1026 	err = search_packidx(&packidx, &idx, repo, id);
1027 	if (err)
1028 		return err;
1029 
1030 	err = open_packed_object(obj, repo, packidx, idx, id);
1031 	if (err)
1032 		return err;
1033 
1034 	err = cache_pack(NULL, (*obj)->path_packfile, packidx, repo);
1035 	return err;
1036 }
1037 
1038 static const struct got_error *
1039 get_delta_chain_max_size(uint64_t *max_size, struct got_delta_chain *deltas)
1040 {
1041 	struct got_delta *delta;
1042 	uint64_t base_size = 0, result_size = 0;
1043 
1044 	*max_size = 0;
1045 	SIMPLEQ_FOREACH(delta, &deltas->entries, entry) {
1046 		/* Plain object types are the delta base. */
1047 		if (delta->type != GOT_OBJ_TYPE_COMMIT &&
1048 		    delta->type != GOT_OBJ_TYPE_TREE &&
1049 		    delta->type != GOT_OBJ_TYPE_BLOB &&
1050 		    delta->type != GOT_OBJ_TYPE_TAG) {
1051 			const struct got_error *err;
1052 			err = got_delta_get_sizes(&base_size, &result_size,
1053 			    delta->delta_buf, delta->delta_len);
1054 			if (err)
1055 				return err;
1056 		} else
1057 			base_size = delta->size;
1058 		if (base_size > *max_size)
1059 			*max_size = base_size;
1060 		if (result_size > *max_size)
1061 			*max_size = result_size;
1062 	}
1063 
1064 	return NULL;
1065 }
1066 
1067 static const struct got_error *
1068 dump_delta_chain_to_file(size_t *result_size, struct got_delta_chain *deltas,
1069     FILE *outfile, struct got_repository *repo)
1070 {
1071 	const struct got_error *err = NULL;
1072 	struct got_delta *delta;
1073 	FILE *base_file = NULL, *accum_file = NULL;
1074 	uint8_t *base_buf = NULL, *accum_buf = NULL;
1075 	size_t accum_size = 0;
1076 	uint64_t max_size;
1077 	int n = 0;
1078 
1079 	*result_size = 0;
1080 
1081 	if (SIMPLEQ_EMPTY(&deltas->entries))
1082 		return got_error(GOT_ERR_BAD_DELTA_CHAIN);
1083 
1084 	/* We process small enough files entirely in memory for speed. */
1085 	err = get_delta_chain_max_size(&max_size, deltas);
1086 	if (err)
1087 		return err;
1088 	if (max_size < GOT_DELTA_RESULT_SIZE_CACHED_MAX) {
1089 		accum_buf = malloc(max_size);
1090 		if (accum_buf == NULL)
1091 			return got_error_from_errno();
1092 	} else {
1093 		base_file = got_opentemp();
1094 		if (base_file == NULL)
1095 			return got_error_from_errno();
1096 
1097 		accum_file = got_opentemp();
1098 		if (accum_file == NULL) {
1099 			err = got_error_from_errno();
1100 			fclose(base_file);
1101 			return err;
1102 		}
1103 	}
1104 
1105 	/* Deltas are ordered in ascending order. */
1106 	SIMPLEQ_FOREACH(delta, &deltas->entries, entry) {
1107 		if (n == 0) {
1108 			struct got_pack *pack;
1109 			size_t base_len;
1110 
1111 			/* Plain object types are the delta base. */
1112 			if (delta->type != GOT_OBJ_TYPE_COMMIT &&
1113 			    delta->type != GOT_OBJ_TYPE_TREE &&
1114 			    delta->type != GOT_OBJ_TYPE_BLOB &&
1115 			    delta->type != GOT_OBJ_TYPE_TAG) {
1116 				err = got_error(GOT_ERR_BAD_DELTA_CHAIN);
1117 				goto done;
1118 			}
1119 
1120 			pack = get_cached_pack(delta->path_packfile, repo);
1121 			if (pack == NULL) {
1122 				err = got_error(GOT_ERR_BAD_DELTA_CHAIN);
1123 				goto done;
1124 			}
1125 
1126 			if (fseeko(pack->packfile, delta->offset + delta->tslen,
1127 			    SEEK_SET) != 0) {
1128 				err = got_error_from_errno();
1129 				goto done;
1130 			}
1131 			if (base_file)
1132 				err = got_inflate_to_file(&base_len,
1133 				    pack->packfile, base_file);
1134 			else {
1135 				err = got_inflate_to_mem(&base_buf, &base_len,
1136 				    pack->packfile);
1137 				if (base_len < max_size) {
1138 					uint8_t *p;
1139 					p = reallocarray(base_buf, 1, max_size);
1140 					if (p == NULL) {
1141 						err = got_error_from_errno();
1142 						goto done;
1143 					}
1144 					base_buf = p;
1145 				}
1146 			}
1147 			if (err)
1148 				goto done;
1149 			n++;
1150 			if (base_file)
1151 				rewind(base_file);
1152 			continue;
1153 		}
1154 
1155 		if (base_buf) {
1156 			err = got_delta_apply_in_mem(base_buf, delta->delta_buf,
1157 			    delta->delta_len, accum_buf, &accum_size);
1158 			n++;
1159 		} else {
1160 			err = got_delta_apply(base_file, delta->delta_buf,
1161 			    delta->delta_len,
1162 			    /* Final delta application writes to output file. */
1163 			    ++n < deltas->nentries ? accum_file : outfile,
1164 			    &accum_size);
1165 		}
1166 		if (err)
1167 			goto done;
1168 
1169 		if (n < deltas->nentries) {
1170 			/* Accumulated delta becomes the new base. */
1171 			if (base_buf) {
1172 				uint8_t *tmp = accum_buf;
1173 				accum_buf = base_buf;
1174 				base_buf = tmp;
1175 			} else {
1176 				FILE *tmp = accum_file;
1177 				accum_file = base_file;
1178 				base_file = tmp;
1179 				rewind(base_file);
1180 				rewind(accum_file);
1181 			}
1182 		}
1183 	}
1184 
1185 done:
1186 	free(base_buf);
1187 	if (accum_buf) {
1188 		size_t len = fwrite(accum_buf, 1, accum_size, outfile);
1189 		free(accum_buf);
1190 		if (len != accum_size)
1191 			return got_ferror(outfile, GOT_ERR_IO);
1192 	}
1193 	if (base_file)
1194 		fclose(base_file);
1195 	if (accum_file)
1196 		fclose(accum_file);
1197 	rewind(outfile);
1198 	if (err == NULL)
1199 		*result_size = accum_size;
1200 	return err;
1201 }
1202 
1203 static const struct got_error *
1204 dump_delta_chain_to_mem(uint8_t **outbuf, size_t *outlen,
1205     struct got_delta_chain *deltas, struct got_repository *repo)
1206 {
1207 	const struct got_error *err = NULL;
1208 	struct got_delta *delta;
1209 	uint8_t *base_buf = NULL, *accum_buf = NULL;
1210 	size_t accum_size;
1211 	uint64_t max_size;
1212 	int n = 0;
1213 
1214 	*outbuf = NULL;
1215 	*outlen = 0;
1216 
1217 	if (SIMPLEQ_EMPTY(&deltas->entries))
1218 		return got_error(GOT_ERR_BAD_DELTA_CHAIN);
1219 
1220 	err = get_delta_chain_max_size(&max_size, deltas);
1221 	if (err)
1222 		return err;
1223 	accum_buf = malloc(max_size);
1224 	if (accum_buf == NULL)
1225 		return got_error_from_errno();
1226 
1227 	/* Deltas are ordered in ascending order. */
1228 	SIMPLEQ_FOREACH(delta, &deltas->entries, entry) {
1229 		if (n == 0) {
1230 			struct got_pack *pack;
1231 			size_t base_len;
1232 
1233 			/* Plain object types are the delta base. */
1234 			if (delta->type != GOT_OBJ_TYPE_COMMIT &&
1235 			    delta->type != GOT_OBJ_TYPE_TREE &&
1236 			    delta->type != GOT_OBJ_TYPE_BLOB &&
1237 			    delta->type != GOT_OBJ_TYPE_TAG) {
1238 				err = got_error(GOT_ERR_BAD_DELTA_CHAIN);
1239 				goto done;
1240 			}
1241 
1242 			pack = get_cached_pack(delta->path_packfile, repo);
1243 			if (pack == NULL) {
1244 				err = got_error(GOT_ERR_BAD_DELTA_CHAIN);
1245 				goto done;
1246 			}
1247 
1248 			if (fseeko(pack->packfile, delta->offset + delta->tslen,
1249 			    SEEK_SET) != 0) {
1250 				err = got_error_from_errno();
1251 				goto done;
1252 			}
1253 			err = got_inflate_to_mem(&base_buf, &base_len,
1254 			    pack->packfile);
1255 			if (base_len < max_size) {
1256 				uint8_t *p;
1257 				p = reallocarray(base_buf, 1, max_size);
1258 				if (p == NULL) {
1259 					err = got_error_from_errno();
1260 					goto done;
1261 				}
1262 				base_buf = p;
1263 			}
1264 			if (err)
1265 				goto done;
1266 			n++;
1267 			continue;
1268 		}
1269 
1270 		err = got_delta_apply_in_mem(base_buf, delta->delta_buf,
1271 		    delta->delta_len, accum_buf, &accum_size);
1272 		n++;
1273 		if (err)
1274 			goto done;
1275 
1276 		if (n < deltas->nentries) {
1277 			/* Accumulated delta becomes the new base. */
1278 			uint8_t *tmp = accum_buf;
1279 			accum_buf = base_buf;
1280 			base_buf = tmp;
1281 		}
1282 	}
1283 
1284 done:
1285 	free(base_buf);
1286 	if (err) {
1287 		free(accum_buf);
1288 		*outbuf = NULL;
1289 		*outlen = 0;
1290 	} else {
1291 		*outbuf = accum_buf;
1292 		*outlen = accum_size;
1293 	}
1294 	return err;
1295 }
1296 
1297 const struct got_error *
1298 got_packfile_extract_object(FILE **f, struct got_object *obj,
1299     struct got_repository *repo)
1300 {
1301 	const struct got_error *err = NULL;
1302 
1303 	if ((obj->flags & GOT_OBJ_FLAG_PACKED) == 0)
1304 		return got_error(GOT_ERR_OBJ_NOT_PACKED);
1305 
1306 	*f = got_opentemp();
1307 	if (*f == NULL) {
1308 		err = got_error(GOT_ERR_FILE_OPEN);
1309 		goto done;
1310 	}
1311 
1312 	if ((obj->flags & GOT_OBJ_FLAG_DELTIFIED) == 0) {
1313 		struct got_pack *pack;
1314 
1315 		pack = get_cached_pack(obj->path_packfile, repo);
1316 		if (pack == NULL) {
1317 			err = cache_pack(&pack, obj->path_packfile, NULL, repo);
1318 			if (err)
1319 				goto done;
1320 		}
1321 
1322 		if (fseeko(pack->packfile, obj->pack_offset, SEEK_SET) != 0) {
1323 			err = got_error_from_errno();
1324 			goto done;
1325 		}
1326 
1327 		err = got_inflate_to_file(&obj->size, pack->packfile, *f);
1328 	} else
1329 		err = dump_delta_chain_to_file(&obj->size, &obj->deltas, *f,
1330 		    repo);
1331 done:
1332 	if (err && *f) {
1333 		fclose(*f);
1334 		*f = NULL;
1335 	}
1336 	return err;
1337 }
1338 
1339 const struct got_error *
1340 got_packfile_extract_object_to_mem(uint8_t **buf, size_t *len,
1341     struct got_object *obj, struct got_repository *repo)
1342 {
1343 	const struct got_error *err = NULL;
1344 
1345 	if ((obj->flags & GOT_OBJ_FLAG_PACKED) == 0)
1346 		return got_error(GOT_ERR_OBJ_NOT_PACKED);
1347 
1348 	if ((obj->flags & GOT_OBJ_FLAG_DELTIFIED) == 0) {
1349 		struct got_pack *pack;
1350 
1351 		pack = get_cached_pack(obj->path_packfile, repo);
1352 		if (pack == NULL) {
1353 			err = cache_pack(&pack, obj->path_packfile, NULL, repo);
1354 			if (err)
1355 				goto done;
1356 		}
1357 
1358 		if (fseeko(pack->packfile, obj->pack_offset, SEEK_SET) != 0) {
1359 			err = got_error_from_errno();
1360 			goto done;
1361 		}
1362 
1363 		err = got_inflate_to_mem(buf, len, pack->packfile);
1364 	} else
1365 		err = dump_delta_chain_to_mem(buf, len, &obj->deltas, repo);
1366 done:
1367 	return err;
1368 }