1 /*
2  * Copyright (c) 2018, 2019 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 #include <sys/uio.h>
21 #include <sys/socket.h>
22 #include <sys/wait.h>
23 #include <sys/mman.h>
24 
25 #include <errno.h>
26 #include <fcntl.h>
27 #include <stdio.h>
28 #include <stdlib.h>
29 #include <string.h>
30 #include <stdint.h>
31 #include <unistd.h>
32 #include <zlib.h>
33 #include <ctype.h>
34 #include <libgen.h>
35 #include <limits.h>
36 #include <time.h>
37 
38 #include "got_compat.h"
39 
40 #include "got_error.h"
41 #include "got_object.h"
42 #include "got_repository.h"
43 #include "got_opentemp.h"
44 #include "got_path.h"
45 
46 #include "got_lib_sha1.h"
47 #include "got_lib_delta.h"
48 #include "got_lib_inflate.h"
49 #include "got_lib_object.h"
50 #include "got_lib_privsep.h"
51 #include "got_lib_object_idcache.h"
52 #include "got_lib_object_cache.h"
53 #include "got_lib_object_parse.h"
54 #include "got_lib_pack.h"
55 #include "got_lib_repository.h"
56 
57 #ifndef MIN
58 #define	MIN(_a,_b) ((_a) < (_b) ? (_a) : (_b))
59 #endif
60 
61 #ifndef nitems
62 #define nitems(_a)	(sizeof((_a)) / sizeof((_a)[0]))
63 #endif
64 
65 struct got_object_id *
66 got_object_get_id(struct got_object *obj)
67 {
68 	return &obj->id;
69 }
70 
71 const struct got_error *
72 got_object_get_id_str(char **outbuf, struct got_object *obj)
73 {
74 	return got_object_id_str(outbuf, &obj->id);
75 }
76 
77 const struct got_error *
78 got_object_get_type(int *type, struct got_repository *repo,
79     struct got_object_id *id)
80 {
81 	const struct got_error *err = NULL;
82 	struct got_object *obj;
83 
84 	err = got_object_open(&obj, repo, id);
85 	if (err)
86 		return err;
87 
88 	switch (obj->type) {
89 	case GOT_OBJ_TYPE_COMMIT:
90 	case GOT_OBJ_TYPE_TREE:
91 	case GOT_OBJ_TYPE_BLOB:
92 	case GOT_OBJ_TYPE_TAG:
93 		*type = obj->type;
94 		break;
95 	default:
96 		err = got_error(GOT_ERR_OBJ_TYPE);
97 		break;
98 	}
99 
100 	got_object_close(obj);
101 	return err;
102 }
103 
104 const struct got_error *
105 got_object_get_path(char **path, struct got_object_id *id,
106     struct got_repository *repo)
107 {
108 	const struct got_error *err = NULL;
109 	char *hex = NULL;
110 	char *path_objects;
111 
112 	*path = NULL;
113 
114 	path_objects = got_repo_get_path_objects(repo);
115 	if (path_objects == NULL)
116 		return got_error_from_errno("got_repo_get_path_objects");
117 
118 	err = got_object_id_str(&hex, id);
119 	if (err)
120 		goto done;
121 
122 	if (asprintf(path, "%s/%.2x/%s", path_objects,
123 	    id->sha1[0], hex + 2) == -1)
124 		err = got_error_from_errno("asprintf");
125 
126 done:
127 	free(hex);
128 	free(path_objects);
129 	return err;
130 }
131 
132 const struct got_error *
133 got_object_open_loose_fd(int *fd, struct got_object_id *id,
134     struct got_repository *repo)
135 {
136 	const struct got_error *err = NULL;
137 	char *path;
138 
139 	err = got_object_get_path(&path, id, repo);
140 	if (err)
141 		return err;
142 	*fd = open(path, O_RDONLY | O_NOFOLLOW | O_CLOEXEC);
143 	if (*fd == -1) {
144 		err = got_error_from_errno2("open", path);
145 		goto done;
146 	}
147 done:
148 	free(path);
149 	return err;
150 }
151 
152 static const struct got_error *
153 request_packed_object(struct got_object **obj, struct got_pack *pack, int idx,
154     struct got_object_id *id)
155 {
156 	const struct got_error *err = NULL;
157 	struct imsgbuf *ibuf = pack->privsep_child->ibuf;
158 
159 	err = got_privsep_send_packed_obj_req(ibuf, idx, id);
160 	if (err)
161 		return err;
162 
163 	err = got_privsep_recv_obj(obj, ibuf);
164 	if (err)
165 		return err;
166 
167 	memcpy(&(*obj)->id, id, sizeof((*obj)->id));
168 
169 	return NULL;
170 }
171 
172 /* Create temporary files used during delta application. */
173 static const struct got_error *
174 pack_child_send_tempfiles(struct imsgbuf *ibuf, struct got_pack *pack)
175 {
176 	const struct got_error *err;
177 	int basefd = -1, accumfd = -1;
178 
179 	/*
180 	 * For performance reasons, the child will keep reusing the
181 	 * same temporary files during every object request.
182 	 * Opening and closing new files for every object request is
183 	 * too expensive during operations such as 'gotadmin pack'.
184 	 */
185 	if (pack->child_has_tempfiles)
186 		return NULL;
187 
188 	basefd = dup(pack->basefd);
189 	if (basefd == -1)
190 		return got_error_from_errno("dup");
191 
192 	accumfd = dup(pack->accumfd);
193 	if (accumfd == -1) {
194 		err = got_error_from_errno("dup");
195 		goto done;
196 	}
197 
198 	err = got_privsep_send_tmpfd(ibuf, basefd);
199 	if (err)
200 		goto done;
201 
202 	err = got_privsep_send_tmpfd(ibuf, accumfd);
203 done:
204 	if (err) {
205 		if (basefd != -1)
206 			close(basefd);
207 		if (accumfd != -1)
208 			close(accumfd);
209 	} else
210 		pack->child_has_tempfiles = 1;
211 	return NULL;
212 }
213 
214 static const struct got_error *
215 request_packed_object_raw(uint8_t **outbuf, off_t *size, size_t *hdrlen,
216     int outfd, struct got_pack *pack, int idx, struct got_object_id *id)
217 {
218 	const struct got_error *err = NULL;
219 	struct imsgbuf *ibuf = pack->privsep_child->ibuf;
220 	int outfd_child;
221 
222 	 err = pack_child_send_tempfiles(ibuf, pack);
223 	 if (err)
224 		return err;
225 
226 	outfd_child = dup(outfd);
227 	if (outfd_child == -1)
228 		return got_error_from_errno("dup");
229 
230 	err = got_privsep_send_packed_raw_obj_req(ibuf, idx, id);
231 	if (err) {
232 		close(outfd_child);
233 		return err;
234 	}
235 
236 	err = got_privsep_send_raw_obj_outfd(ibuf, outfd_child);
237 	if (err)
238 		return err;
239 
240 	err = got_privsep_recv_raw_obj(outbuf, size, hdrlen, ibuf);
241 	if (err)
242 		return err;
243 
244 	return NULL;
245 }
246 
247 static const struct got_error *
248 read_packed_object_privsep(struct got_object **obj,
249     struct got_repository *repo, struct got_pack *pack,
250     struct got_packidx *packidx, int idx, struct got_object_id *id)
251 {
252 	const struct got_error *err = NULL;
253 
254 	if (pack->privsep_child == NULL) {
255 		err = got_pack_start_privsep_child(pack, packidx);
256 		if (err)
257 			return err;
258 	}
259 
260 	return request_packed_object(obj, pack, idx, id);
261 }
262 
263 static const struct got_error *
264 read_packed_object_raw_privsep(uint8_t **outbuf, off_t *size, size_t *hdrlen,
265     int outfd, struct got_pack *pack, struct got_packidx *packidx, int idx,
266     struct got_object_id *id)
267 {
268 	const struct got_error *err = NULL;
269 
270 	if (pack->privsep_child == NULL) {
271 		err = got_pack_start_privsep_child(pack, packidx);
272 		if (err)
273 			return err;
274 	}
275 
276 	return request_packed_object_raw(outbuf, size, hdrlen, outfd, pack,
277 	    idx, id);
278 }
279 
280 const struct got_error *
281 got_object_open_packed(struct got_object **obj, struct got_object_id *id,
282     struct got_repository *repo)
283 {
284 	const struct got_error *err = NULL;
285 	struct got_pack *pack = NULL;
286 	struct got_packidx *packidx = NULL;
287 	int idx;
288 	char *path_packfile;
289 
290 	err = got_repo_search_packidx(&packidx, &idx, repo, id);
291 	if (err)
292 		return err;
293 
294 	err = got_packidx_get_packfile_path(&path_packfile,
295 	    packidx->path_packidx);
296 	if (err)
297 		return err;
298 
299 	pack = got_repo_get_cached_pack(repo, path_packfile);
300 	if (pack == NULL) {
301 		err = got_repo_cache_pack(&pack, repo, path_packfile, packidx);
302 		if (err)
303 			goto done;
304 	}
305 
306 	err = read_packed_object_privsep(obj, repo, pack, packidx, idx, id);
307 	if (err)
308 		goto done;
309 done:
310 	free(path_packfile);
311 	return err;
312 }
313 
314 const struct got_error *
315 got_object_open_from_packfile(struct got_object **obj, struct got_object_id *id,
316     struct got_pack *pack, struct got_packidx *packidx, int obj_idx,
317     struct got_repository *repo)
318 {
319 	return read_packed_object_privsep(obj, repo, pack, packidx,
320 	    obj_idx, id);
321 }
322 
323 const struct got_error *
324 got_object_read_raw_delta(uint64_t *base_size, uint64_t *result_size,
325     off_t *delta_size, off_t *delta_compressed_size, off_t *delta_offset,
326     off_t *delta_out_offset, struct got_object_id **base_id, int delta_cache_fd,
327     struct got_packidx *packidx, int obj_idx, struct got_object_id *id,
328     struct got_repository *repo)
329 {
330 	const struct got_error *err = NULL;
331 	struct got_pack *pack = NULL;
332 	char *path_packfile;
333 
334 	*base_size = 0;
335 	*result_size = 0;
336 	*delta_size = 0;
337 	*delta_compressed_size = 0;
338 	*delta_offset = 0;
339 	*delta_out_offset = 0;
340 
341 	err = got_packidx_get_packfile_path(&path_packfile,
342 	    packidx->path_packidx);
343 	if (err)
344 		return err;
345 
346 	pack = got_repo_get_cached_pack(repo, path_packfile);
347 	if (pack == NULL) {
348 		err = got_repo_cache_pack(&pack, repo, path_packfile, packidx);
349 		if (err)
350 			return err;
351 	}
352 
353 	if (pack->privsep_child == NULL) {
354 		err = got_pack_start_privsep_child(pack, packidx);
355 		if (err)
356 			return err;
357 	}
358 
359 	if (!pack->child_has_delta_outfd) {
360 		int outfd_child;
361 		outfd_child = dup(delta_cache_fd);
362 		if (outfd_child == -1)
363 			return got_error_from_errno("dup");
364 		err = got_privsep_send_raw_delta_outfd(
365 		    pack->privsep_child->ibuf, outfd_child);
366 		if (err)
367 			return err;
368 		pack->child_has_delta_outfd = 1;
369 	}
370 
371 	err = got_privsep_send_raw_delta_req(pack->privsep_child->ibuf,
372 	    obj_idx, id);
373 	if (err)
374 		return err;
375 
376 	return got_privsep_recv_raw_delta(base_size, result_size, delta_size,
377 	    delta_compressed_size, delta_offset, delta_out_offset, base_id,
378 	    pack->privsep_child->ibuf);
379 }
380 
381 static const struct got_error *
382 request_object(struct got_object **obj, struct got_object_id *id,
383     struct got_repository *repo, int fd)
384 {
385 	const struct got_error *err = NULL;
386 	struct imsgbuf *ibuf;
387 
388 	ibuf = repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_OBJECT].ibuf;
389 
390 	err = got_privsep_send_obj_req(ibuf, fd, id);
391 	if (err)
392 		return err;
393 
394 	return got_privsep_recv_obj(obj, ibuf);
395 }
396 
397 static const struct got_error *
398 request_raw_object(uint8_t **outbuf, off_t *size, size_t *hdrlen, int outfd,
399     struct got_object_id *id, struct got_repository *repo, int infd)
400 {
401 	const struct got_error *err = NULL;
402 	struct imsgbuf *ibuf;
403 	int outfd_child;
404 
405 	ibuf = repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_OBJECT].ibuf;
406 
407 	outfd_child = dup(outfd);
408 	if (outfd_child == -1)
409 		return got_error_from_errno("dup");
410 
411 	err = got_privsep_send_raw_obj_req(ibuf, infd, id);
412 	if (err)
413 		return err;
414 
415 	err = got_privsep_send_raw_obj_outfd(ibuf, outfd_child);
416 	if (err)
417 		return err;
418 
419 	return got_privsep_recv_raw_obj(outbuf, size, hdrlen, ibuf);
420 }
421 
422 static const struct got_error *
423 start_read_object_child(struct got_repository *repo)
424 {
425 	const struct got_error *err = NULL;
426 	int imsg_fds[2];
427 	pid_t pid;
428 	struct imsgbuf *ibuf;
429 
430 	ibuf = calloc(1, sizeof(*ibuf));
431 	if (ibuf == NULL)
432 		return got_error_from_errno("calloc");
433 
434 	if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, imsg_fds) == -1) {
435 		err = got_error_from_errno("socketpair");
436 		free(ibuf);
437 		return err;
438 	}
439 
440 	pid = fork();
441 	if (pid == -1) {
442 		err = got_error_from_errno("fork");
443 		free(ibuf);
444 		return err;
445 	}
446 	else if (pid == 0) {
447 		got_privsep_exec_child(imsg_fds, GOT_PATH_PROG_READ_OBJECT,
448 		    repo->path);
449 		/* not reached */
450 	}
451 
452 	if (close(imsg_fds[1]) == -1) {
453 		err = got_error_from_errno("close");
454 		free(ibuf);
455 		return err;
456 	}
457 
458 	repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_OBJECT].imsg_fd =
459 	    imsg_fds[0];
460 	repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_OBJECT].pid = pid;
461 	imsg_init(ibuf, imsg_fds[0]);
462 	repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_OBJECT].ibuf = ibuf;
463 
464 	return NULL;
465 }
466 
467 const struct got_error *
468 got_object_read_header_privsep(struct got_object **obj,
469     struct got_object_id *id, struct got_repository *repo, int obj_fd)
470 {
471 	const struct got_error *err;
472 
473 	if (repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_OBJECT].imsg_fd != -1)
474 		return request_object(obj, id, repo, obj_fd);
475 
476 	err = start_read_object_child(repo);
477 	if (err) {
478 		close(obj_fd);
479 		return err;
480 	}
481 
482 	return request_object(obj, id, repo, obj_fd);
483 }
484 
485 static const struct got_error *
486 read_object_raw_privsep(uint8_t **outbuf, off_t *size, size_t *hdrlen,
487     int outfd, struct got_object_id *id, struct got_repository *repo,
488     int obj_fd)
489 {
490 	const struct got_error *err;
491 
492 	if (repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_OBJECT].imsg_fd != -1)
493 		return request_raw_object(outbuf, size, hdrlen, outfd, id,
494 		    repo, obj_fd);
495 
496 	err = start_read_object_child(repo);
497 	if (err)
498 		return err;
499 
500 	return request_raw_object(outbuf, size, hdrlen, outfd, id, repo,
501 	    obj_fd);
502 }
503 
504 const struct got_error *
505 got_object_open(struct got_object **obj, struct got_repository *repo,
506     struct got_object_id *id)
507 {
508 	const struct got_error *err = NULL;
509 	int fd;
510 
511 	*obj = got_repo_get_cached_object(repo, id);
512 	if (*obj != NULL) {
513 		(*obj)->refcnt++;
514 		return NULL;
515 	}
516 
517 	err = got_object_open_packed(obj, id, repo);
518 	if (err && err->code != GOT_ERR_NO_OBJ)
519 		return err;
520 	if (*obj) {
521 		(*obj)->refcnt++;
522 		return got_repo_cache_object(repo, id, *obj);
523 	}
524 
525 	err = got_object_open_loose_fd(&fd, id, repo);
526 	if (err) {
527 		if (err->code == GOT_ERR_ERRNO && errno == ENOENT)
528 			err = got_error_no_obj(id);
529 		return err;
530 	}
531 
532 	err = got_object_read_header_privsep(obj, id, repo, fd);
533 	if (err)
534 		return err;
535 
536 	memcpy((*obj)->id.sha1, id->sha1, SHA1_DIGEST_LENGTH);
537 
538 	(*obj)->refcnt++;
539 	return got_repo_cache_object(repo, id, *obj);
540 }
541 
542 /* *outfd must be initialized to -1 by caller */
543 const struct got_error *
544 got_object_raw_open(struct got_raw_object **obj, int *outfd,
545     struct got_repository *repo, struct got_object_id *id)
546 {
547 	const struct got_error *err = NULL;
548 	struct got_packidx *packidx = NULL;
549 	int idx;
550 	uint8_t *outbuf = NULL;
551 	off_t size = 0;
552 	size_t hdrlen = 0;
553 	char *path_packfile = NULL;
554 
555 	*obj = got_repo_get_cached_raw_object(repo, id);
556 	if (*obj != NULL) {
557 		(*obj)->refcnt++;
558 		return NULL;
559 	}
560 
561 	if (*outfd == -1) {
562 		*outfd = got_opentempfd();
563 		if (*outfd == -1)
564 			return got_error_from_errno("got_opentempfd");
565 	}
566 
567 	err = got_repo_search_packidx(&packidx, &idx, repo, id);
568 	if (err == NULL) {
569 		struct got_pack *pack = NULL;
570 
571 		err = got_packidx_get_packfile_path(&path_packfile,
572 		    packidx->path_packidx);
573 		if (err)
574 			goto done;
575 
576 		pack = got_repo_get_cached_pack(repo, path_packfile);
577 		if (pack == NULL) {
578 			err = got_repo_cache_pack(&pack, repo, path_packfile,
579 			    packidx);
580 			if (err)
581 				goto done;
582 		}
583 		err = read_packed_object_raw_privsep(&outbuf, &size, &hdrlen,
584 		    *outfd, pack, packidx, idx, id);
585 		if (err)
586 			goto done;
587 	} else if (err->code == GOT_ERR_NO_OBJ) {
588 		int fd;
589 
590 		err = got_object_open_loose_fd(&fd, id, repo);
591 		if (err)
592 			goto done;
593 		err = read_object_raw_privsep(&outbuf, &size, &hdrlen, *outfd,
594 		    id, repo, fd);
595 		if (err)
596 			goto done;
597 	}
598 
599 	*obj = calloc(1, sizeof(**obj));
600 	if (*obj == NULL) {
601 		err = got_error_from_errno("calloc");
602 		goto done;
603 	}
604 	(*obj)->fd = -1;
605 
606 	if (outbuf) {
607 		(*obj)->data = outbuf;
608 	} else {
609 		struct stat sb;
610 		if (fstat(*outfd, &sb) == -1) {
611 			err = got_error_from_errno("fstat");
612 			goto done;
613 		}
614 
615 		if (sb.st_size != hdrlen + size) {
616 			err = got_error(GOT_ERR_PRIVSEP_LEN);
617 			goto done;
618 		}
619 #ifndef GOT_PACK_NO_MMAP
620 		if (hdrlen + size > 0) {
621 			(*obj)->data = mmap(NULL, hdrlen + size, PROT_READ,
622 			    MAP_PRIVATE, *outfd, 0);
623 			if ((*obj)->data == MAP_FAILED) {
624 				if (errno != ENOMEM) {
625 					err = got_error_from_errno("mmap");
626 					goto done;
627 				}
628 				(*obj)->data = NULL;
629 			} else {
630 				(*obj)->fd = *outfd;
631 				*outfd = -1;
632 			}
633 		}
634 #endif
635 		if (*outfd != -1) {
636 			(*obj)->f = fdopen(*outfd, "r");
637 			if ((*obj)->f == NULL) {
638 				err = got_error_from_errno("fdopen");
639 				goto done;
640 			}
641 			*outfd = -1;
642 		}
643 	}
644 	(*obj)->hdrlen = hdrlen;
645 	(*obj)->size = size;
646 	err = got_repo_cache_raw_object(repo, id, *obj);
647 done:
648 	free(path_packfile);
649 	if (err) {
650 		if (*obj) {
651 			got_object_raw_close(*obj);
652 			*obj = NULL;
653 		}
654 		free(outbuf);
655 	} else
656 		(*obj)->refcnt++;
657 	return err;
658 }
659 
660 const struct got_error *
661 got_object_open_by_id_str(struct got_object **obj, struct got_repository *repo,
662     const char *id_str)
663 {
664 	struct got_object_id id;
665 
666 	if (!got_parse_sha1_digest(id.sha1, id_str))
667 		return got_error_path(id_str, GOT_ERR_BAD_OBJ_ID_STR);
668 
669 	return got_object_open(obj, repo, &id);
670 }
671 
672 const struct got_error *
673 got_object_resolve_id_str(struct got_object_id **id,
674     struct got_repository *repo, const char *id_str)
675 {
676 	const struct got_error *err = NULL;
677 	struct got_object *obj;
678 
679 	err = got_object_open_by_id_str(&obj, repo, id_str);
680 	if (err)
681 		return err;
682 
683 	*id = got_object_id_dup(got_object_get_id(obj));
684 	got_object_close(obj);
685 	if (*id == NULL)
686 		return got_error_from_errno("got_object_id_dup");
687 
688 	return NULL;
689 }
690 
691 static const struct got_error *
692 request_packed_commit(struct got_commit_object **commit, struct got_pack *pack,
693     int pack_idx, struct got_object_id *id)
694 {
695 	const struct got_error *err = NULL;
696 
697 	err = got_privsep_send_commit_req(pack->privsep_child->ibuf, -1, id,
698 	    pack_idx);
699 	if (err)
700 		return err;
701 
702 	err = got_privsep_recv_commit(commit, pack->privsep_child->ibuf);
703 	if (err)
704 		return err;
705 
706 	(*commit)->flags |= GOT_COMMIT_FLAG_PACKED;
707 	return NULL;
708 }
709 
710 static const struct got_error *
711 read_packed_commit_privsep(struct got_commit_object **commit,
712     struct got_pack *pack, struct got_packidx *packidx, int idx,
713     struct got_object_id *id)
714 {
715 	const struct got_error *err = NULL;
716 
717 	if (pack->privsep_child)
718 		return request_packed_commit(commit, pack, idx, id);
719 
720 	err = got_pack_start_privsep_child(pack, packidx);
721 	if (err)
722 		return err;
723 
724 	return request_packed_commit(commit, pack, idx, id);
725 }
726 
727 static const struct got_error *
728 request_commit(struct got_commit_object **commit, struct got_repository *repo,
729     int fd, struct got_object_id *id)
730 {
731 	const struct got_error *err = NULL;
732 	struct imsgbuf *ibuf;
733 
734 	ibuf = repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_COMMIT].ibuf;
735 
736 	err = got_privsep_send_commit_req(ibuf, fd, id, -1);
737 	if (err)
738 		return err;
739 
740 	return got_privsep_recv_commit(commit, ibuf);
741 }
742 
743 static const struct got_error *
744 read_commit_privsep(struct got_commit_object **commit, int obj_fd,
745     struct got_object_id *id, struct got_repository *repo)
746 {
747 	const struct got_error *err;
748 	int imsg_fds[2];
749 	pid_t pid;
750 	struct imsgbuf *ibuf;
751 
752 	if (repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_COMMIT].imsg_fd != -1)
753 		return request_commit(commit, repo, obj_fd, id);
754 
755 	ibuf = calloc(1, sizeof(*ibuf));
756 	if (ibuf == NULL)
757 		return got_error_from_errno("calloc");
758 
759 	if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, imsg_fds) == -1) {
760 		err = got_error_from_errno("socketpair");
761 		free(ibuf);
762 		return err;
763 	}
764 
765 	pid = fork();
766 	if (pid == -1) {
767 		err = got_error_from_errno("fork");
768 		free(ibuf);
769 		return err;
770 	}
771 	else if (pid == 0) {
772 		got_privsep_exec_child(imsg_fds, GOT_PATH_PROG_READ_COMMIT,
773 		    repo->path);
774 		/* not reached */
775 	}
776 
777 	if (close(imsg_fds[1]) == -1) {
778 		err = got_error_from_errno("close");
779 		free(ibuf);
780 		return err;
781 	}
782 	repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_COMMIT].imsg_fd =
783 	    imsg_fds[0];
784 	repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_COMMIT].pid = pid;
785 	imsg_init(ibuf, imsg_fds[0]);
786 	repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_COMMIT].ibuf = ibuf;
787 
788 	return request_commit(commit, repo, obj_fd, id);
789 }
790 
791 
792 static const struct got_error *
793 open_commit(struct got_commit_object **commit,
794     struct got_repository *repo, struct got_object_id *id, int check_cache)
795 {
796 	const struct got_error *err = NULL;
797 	struct got_packidx *packidx = NULL;
798 	int idx;
799 	char *path_packfile = NULL;
800 
801 	if (check_cache) {
802 		*commit = got_repo_get_cached_commit(repo, id);
803 		if (*commit != NULL) {
804 			(*commit)->refcnt++;
805 			return NULL;
806 		}
807 	} else
808 		*commit = NULL;
809 
810 	err = got_repo_search_packidx(&packidx, &idx, repo, id);
811 	if (err == NULL) {
812 		struct got_pack *pack = NULL;
813 
814 		err = got_packidx_get_packfile_path(&path_packfile,
815 		    packidx->path_packidx);
816 		if (err)
817 			return err;
818 
819 		pack = got_repo_get_cached_pack(repo, path_packfile);
820 		if (pack == NULL) {
821 			err = got_repo_cache_pack(&pack, repo, path_packfile,
822 			    packidx);
823 			if (err)
824 				goto done;
825 		}
826 		err = read_packed_commit_privsep(commit, pack,
827 		    packidx, idx, id);
828 	} else if (err->code == GOT_ERR_NO_OBJ) {
829 		int fd;
830 
831 		err = got_object_open_loose_fd(&fd, id, repo);
832 		if (err)
833 			return err;
834 		err = read_commit_privsep(commit, fd, id, repo);
835 	}
836 
837 	if (err == NULL) {
838 		(*commit)->refcnt++;
839 		err = got_repo_cache_commit(repo, id, *commit);
840 	}
841 done:
842 	free(path_packfile);
843 	return err;
844 }
845 
846 const struct got_error *
847 got_object_open_as_commit(struct got_commit_object **commit,
848     struct got_repository *repo, struct got_object_id *id)
849 {
850 	*commit = got_repo_get_cached_commit(repo, id);
851 	if (*commit != NULL) {
852 		(*commit)->refcnt++;
853 		return NULL;
854 	}
855 
856 	return open_commit(commit, repo, id, 0);
857 }
858 
859 const struct got_error *
860 got_object_commit_open(struct got_commit_object **commit,
861     struct got_repository *repo, struct got_object *obj)
862 {
863 	return open_commit(commit, repo, got_object_get_id(obj), 1);
864 }
865 
866 const struct got_error *
867 got_object_qid_alloc(struct got_object_qid **qid, struct got_object_id *id)
868 {
869 	*qid = calloc(1, sizeof(**qid));
870 	if (*qid == NULL)
871 		return got_error_from_errno("calloc");
872 
873 	memcpy(&(*qid)->id, id, sizeof((*qid)->id));
874 	return NULL;
875 }
876 
877 const struct got_error *
878 got_object_id_queue_copy(const struct got_object_id_queue *src,
879     struct got_object_id_queue *dest)
880 {
881 	const struct got_error *err;
882 	struct got_object_qid *qid;
883 
884 	STAILQ_FOREACH(qid, src, entry) {
885 		struct got_object_qid *new;
886 		/*
887 		 * Deep-copy the object ID only. Let the caller deal
888 		 * with setting up the new->data pointer if needed.
889 		 */
890 		err = got_object_qid_alloc(&new, &qid->id);
891 		if (err) {
892 			got_object_id_queue_free(dest);
893 			return err;
894 		}
895 		STAILQ_INSERT_TAIL(dest, new, entry);
896 	}
897 
898 	return NULL;
899 }
900 
901 static const struct got_error *
902 request_packed_tree(struct got_tree_object **tree, struct got_pack *pack,
903     int pack_idx, struct got_object_id *id)
904 {
905 	const struct got_error *err = NULL;
906 
907 	err = got_privsep_send_tree_req(pack->privsep_child->ibuf, -1, id,
908 	    pack_idx);
909 	if (err)
910 		return err;
911 
912 	return got_privsep_recv_tree(tree, pack->privsep_child->ibuf);
913 }
914 
915 static const struct got_error *
916 read_packed_tree_privsep(struct got_tree_object **tree,
917     struct got_pack *pack, struct got_packidx *packidx, int idx,
918     struct got_object_id *id)
919 {
920 	const struct got_error *err = NULL;
921 
922 	if (pack->privsep_child)
923 		return request_packed_tree(tree, pack, idx, id);
924 
925 	err = got_pack_start_privsep_child(pack, packidx);
926 	if (err)
927 		return err;
928 
929 	return request_packed_tree(tree, pack, idx, id);
930 }
931 
932 static const struct got_error *
933 request_tree(struct got_tree_object **tree, struct got_repository *repo,
934     int fd, struct got_object_id *id)
935 {
936 	const struct got_error *err = NULL;
937 	struct imsgbuf *ibuf;
938 
939 	ibuf = repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_TREE].ibuf;
940 
941 	err = got_privsep_send_tree_req(ibuf, fd, id, -1);
942 	if (err)
943 		return err;
944 
945 	return got_privsep_recv_tree(tree, ibuf);
946 }
947 
948 static const struct got_error *
949 read_tree_privsep(struct got_tree_object **tree, int obj_fd,
950     struct got_object_id *id, struct got_repository *repo)
951 {
952 	const struct got_error *err;
953 	int imsg_fds[2];
954 	pid_t pid;
955 	struct imsgbuf *ibuf;
956 
957 	if (repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_TREE].imsg_fd != -1)
958 		return request_tree(tree, repo, obj_fd, id);
959 
960 	ibuf = calloc(1, sizeof(*ibuf));
961 	if (ibuf == NULL)
962 		return got_error_from_errno("calloc");
963 
964 	if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, imsg_fds) == -1) {
965 		err = got_error_from_errno("socketpair");
966 		free(ibuf);
967 		return err;
968 	}
969 
970 	pid = fork();
971 	if (pid == -1) {
972 		err = got_error_from_errno("fork");
973 		free(ibuf);
974 		return err;
975 	}
976 	else if (pid == 0) {
977 		got_privsep_exec_child(imsg_fds, GOT_PATH_PROG_READ_TREE,
978 		    repo->path);
979 		/* not reached */
980 	}
981 
982 	if (close(imsg_fds[1]) == -1) {
983 		err = got_error_from_errno("close");
984 		free(ibuf);
985 		return err;
986 	}
987 	repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_TREE].imsg_fd =
988 	    imsg_fds[0];
989 	repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_TREE].pid = pid;
990 	imsg_init(ibuf, imsg_fds[0]);
991 	repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_TREE].ibuf = ibuf;
992 
993 
994 	return request_tree(tree, repo, obj_fd, id);
995 }
996 
997 static const struct got_error *
998 open_tree(struct got_tree_object **tree, struct got_repository *repo,
999     struct got_object_id *id, int check_cache)
1000 {
1001 	const struct got_error *err = NULL;
1002 	struct got_packidx *packidx = NULL;
1003 	int idx;
1004 	char *path_packfile = NULL;
1005 
1006 	if (check_cache) {
1007 		*tree = got_repo_get_cached_tree(repo, id);
1008 		if (*tree != NULL) {
1009 			(*tree)->refcnt++;
1010 			return NULL;
1011 		}
1012 	} else
1013 		*tree = NULL;
1014 
1015 	err = got_repo_search_packidx(&packidx, &idx, repo, id);
1016 	if (err == NULL) {
1017 		struct got_pack *pack = NULL;
1018 
1019 		err = got_packidx_get_packfile_path(&path_packfile,
1020 		    packidx->path_packidx);
1021 		if (err)
1022 			return err;
1023 
1024 		pack = got_repo_get_cached_pack(repo, path_packfile);
1025 		if (pack == NULL) {
1026 			err = got_repo_cache_pack(&pack, repo, path_packfile,
1027 			    packidx);
1028 			if (err)
1029 				goto done;
1030 		}
1031 		err = read_packed_tree_privsep(tree, pack,
1032 		    packidx, idx, id);
1033 	} else if (err->code == GOT_ERR_NO_OBJ) {
1034 		int fd;
1035 
1036 		err = got_object_open_loose_fd(&fd, id, repo);
1037 		if (err)
1038 			return err;
1039 		err = read_tree_privsep(tree, fd, id, repo);
1040 	}
1041 
1042 	if (err == NULL) {
1043 		(*tree)->refcnt++;
1044 		err = got_repo_cache_tree(repo, id, *tree);
1045 	}
1046 done:
1047 	free(path_packfile);
1048 	return err;
1049 }
1050 
1051 const struct got_error *
1052 got_object_open_as_tree(struct got_tree_object **tree,
1053     struct got_repository *repo, struct got_object_id *id)
1054 {
1055 	*tree = got_repo_get_cached_tree(repo, id);
1056 	if (*tree != NULL) {
1057 		(*tree)->refcnt++;
1058 		return NULL;
1059 	}
1060 
1061 	return open_tree(tree, repo, id, 0);
1062 }
1063 
1064 const struct got_error *
1065 got_object_tree_open(struct got_tree_object **tree,
1066     struct got_repository *repo, struct got_object *obj)
1067 {
1068 	return open_tree(tree, repo, got_object_get_id(obj), 1);
1069 }
1070 
1071 int
1072 got_object_tree_get_nentries(struct got_tree_object *tree)
1073 {
1074 	return tree->nentries;
1075 }
1076 
1077 struct got_tree_entry *
1078 got_object_tree_get_first_entry(struct got_tree_object *tree)
1079 {
1080 	return got_object_tree_get_entry(tree, 0);
1081 }
1082 
1083 struct got_tree_entry *
1084 got_object_tree_get_last_entry(struct got_tree_object *tree)
1085 {
1086 	return got_object_tree_get_entry(tree, tree->nentries - 1);
1087 }
1088 
1089 struct got_tree_entry *
1090 got_object_tree_get_entry(struct got_tree_object *tree, int i)
1091 {
1092 	if (i < 0 || i >= tree->nentries)
1093 		return NULL;
1094 	return &tree->entries[i];
1095 }
1096 
1097 mode_t
1098 got_tree_entry_get_mode(struct got_tree_entry *te)
1099 {
1100 	return te->mode;
1101 }
1102 
1103 const char *
1104 got_tree_entry_get_name(struct got_tree_entry *te)
1105 {
1106 	return &te->name[0];
1107 }
1108 
1109 struct got_object_id *
1110 got_tree_entry_get_id(struct got_tree_entry *te)
1111 {
1112 	return &te->id;
1113 }
1114 
1115 const struct got_error *
1116 got_object_blob_read_to_str(char **s, struct got_blob_object *blob)
1117 {
1118 	const struct got_error *err = NULL;
1119 	size_t len, totlen, hdrlen, offset;
1120 
1121 	*s = NULL;
1122 
1123 	hdrlen = got_object_blob_get_hdrlen(blob);
1124 	totlen = 0;
1125 	offset = 0;
1126 	do {
1127 		char *p;
1128 
1129 		err = got_object_blob_read_block(&len, blob);
1130 		if (err)
1131 			return err;
1132 
1133 		if (len == 0)
1134 			break;
1135 
1136 		totlen += len - hdrlen;
1137 		p = realloc(*s, totlen + 1);
1138 		if (p == NULL) {
1139 			err = got_error_from_errno("realloc");
1140 			free(*s);
1141 			*s = NULL;
1142 			return err;
1143 		}
1144 		*s = p;
1145 		/* Skip blob object header first time around. */
1146 		memcpy(*s + offset,
1147 		    got_object_blob_get_read_buf(blob) + hdrlen, len - hdrlen);
1148 		hdrlen = 0;
1149 		offset = totlen;
1150 	} while (len > 0);
1151 
1152 	(*s)[totlen] = '\0';
1153 	return NULL;
1154 }
1155 
1156 const struct got_error *
1157 got_tree_entry_get_symlink_target(char **link_target, struct got_tree_entry *te,
1158     struct got_repository *repo)
1159 {
1160 	const struct got_error *err = NULL;
1161 	struct got_blob_object *blob = NULL;
1162 	int fd = -1;
1163 
1164 	*link_target = NULL;
1165 
1166 	if (!got_object_tree_entry_is_symlink(te))
1167 		return got_error(GOT_ERR_TREE_ENTRY_TYPE);
1168 
1169 	fd = got_opentempfd();
1170 	if (fd == -1) {
1171 		err = got_error_from_errno("got_opentempfd");
1172 		goto done;
1173 	}
1174 
1175 	err = got_object_open_as_blob(&blob, repo,
1176 	    got_tree_entry_get_id(te), PATH_MAX, fd);
1177 	if (err)
1178 		goto done;
1179 
1180 	err = got_object_blob_read_to_str(link_target, blob);
1181 done:
1182 	if (fd != -1 && close(fd) == -1 && err == NULL)
1183 		err = got_error_from_errno("close");
1184 	if (blob)
1185 		got_object_blob_close(blob);
1186 	if (err) {
1187 		free(*link_target);
1188 		*link_target = NULL;
1189 	}
1190 	return err;
1191 }
1192 
1193 int
1194 got_tree_entry_get_index(struct got_tree_entry *te)
1195 {
1196 	return te->idx;
1197 }
1198 
1199 struct got_tree_entry *
1200 got_tree_entry_get_next(struct got_tree_object *tree,
1201     struct got_tree_entry *te)
1202 {
1203 	return got_object_tree_get_entry(tree, te->idx + 1);
1204 }
1205 
1206 struct got_tree_entry *
1207 got_tree_entry_get_prev(struct got_tree_object *tree,
1208     struct got_tree_entry *te)
1209 {
1210 	return got_object_tree_get_entry(tree, te->idx - 1);
1211 }
1212 
1213 static const struct got_error *
1214 request_packed_blob(uint8_t **outbuf, size_t *size, size_t *hdrlen, int outfd,
1215     struct got_pack *pack, struct got_packidx *packidx, int idx,
1216     struct got_object_id *id)
1217 {
1218 	const struct got_error *err = NULL;
1219 	struct imsgbuf *ibuf = pack->privsep_child->ibuf;
1220 	int outfd_child;
1221 
1222 	 err = pack_child_send_tempfiles(ibuf, pack);
1223 	 if (err)
1224 		return err;
1225 
1226 	outfd_child = dup(outfd);
1227 	if (outfd_child == -1)
1228 		return got_error_from_errno("dup");
1229 
1230 	err = got_privsep_send_blob_req(pack->privsep_child->ibuf, -1, id, idx);
1231 	if (err)
1232 		return err;
1233 
1234 	err = got_privsep_send_blob_outfd(pack->privsep_child->ibuf,
1235 	    outfd_child);
1236 	if (err) {
1237 		return err;
1238 	}
1239 
1240 	err = got_privsep_recv_blob(outbuf, size, hdrlen,
1241 	    pack->privsep_child->ibuf);
1242 	if (err)
1243 		return err;
1244 
1245 	if (lseek(outfd, SEEK_SET, 0) == -1)
1246 		err = got_error_from_errno("lseek");
1247 
1248 	return err;
1249 }
1250 
1251 static const struct got_error *
1252 read_packed_blob_privsep(uint8_t **outbuf, size_t *size, size_t *hdrlen,
1253     int outfd, struct got_pack *pack, struct got_packidx *packidx, int idx,
1254     struct got_object_id *id)
1255 {
1256 	const struct got_error *err = NULL;
1257 
1258 	if (pack->privsep_child == NULL) {
1259 		err = got_pack_start_privsep_child(pack, packidx);
1260 		if (err)
1261 			return err;
1262 	}
1263 
1264 	return request_packed_blob(outbuf, size, hdrlen, outfd, pack, packidx,
1265 	    idx, id);
1266 }
1267 
1268 static const struct got_error *
1269 request_blob(uint8_t **outbuf, size_t *size, size_t *hdrlen, int outfd,
1270     int infd, struct got_object_id *id, struct imsgbuf *ibuf)
1271 {
1272 	const struct got_error *err = NULL;
1273 	int outfd_child;
1274 
1275 	outfd_child = dup(outfd);
1276 	if (outfd_child == -1)
1277 		return got_error_from_errno("dup");
1278 
1279 	err = got_privsep_send_blob_req(ibuf, infd, id, -1);
1280 	if (err)
1281 		return err;
1282 
1283 	err = got_privsep_send_blob_outfd(ibuf, outfd_child);
1284 	if (err)
1285 		return err;
1286 
1287 	err = got_privsep_recv_blob(outbuf, size, hdrlen, ibuf);
1288 	if (err)
1289 		return err;
1290 
1291 	if (lseek(outfd, SEEK_SET, 0) == -1)
1292 		return got_error_from_errno("lseek");
1293 
1294 	return err;
1295 }
1296 
1297 static const struct got_error *
1298 read_blob_privsep(uint8_t **outbuf, size_t *size, size_t *hdrlen,
1299     int outfd, int infd, struct got_object_id *id, struct got_repository *repo)
1300 {
1301 	const struct got_error *err;
1302 	int imsg_fds[2];
1303 	pid_t pid;
1304 	struct imsgbuf *ibuf;
1305 
1306 	if (repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_BLOB].imsg_fd != -1) {
1307 		ibuf = repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_BLOB].ibuf;
1308 		return request_blob(outbuf, size, hdrlen, outfd, infd, id,
1309 		    ibuf);
1310 	}
1311 
1312 	ibuf = calloc(1, sizeof(*ibuf));
1313 	if (ibuf == NULL)
1314 		return got_error_from_errno("calloc");
1315 
1316 	if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, imsg_fds) == -1) {
1317 		err = got_error_from_errno("socketpair");
1318 		free(ibuf);
1319 		return err;
1320 	}
1321 
1322 	pid = fork();
1323 	if (pid == -1) {
1324 		err = got_error_from_errno("fork");
1325 		free(ibuf);
1326 		return err;
1327 	}
1328 	else if (pid == 0) {
1329 		got_privsep_exec_child(imsg_fds, GOT_PATH_PROG_READ_BLOB,
1330 		    repo->path);
1331 		/* not reached */
1332 	}
1333 
1334 	if (close(imsg_fds[1]) == -1) {
1335 		err = got_error_from_errno("close");
1336 		free(ibuf);
1337 		return err;
1338 	}
1339 	repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_BLOB].imsg_fd =
1340 	    imsg_fds[0];
1341 	repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_BLOB].pid = pid;
1342 	imsg_init(ibuf, imsg_fds[0]);
1343 	repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_BLOB].ibuf = ibuf;
1344 
1345 	return request_blob(outbuf, size, hdrlen, outfd, infd, id, ibuf);
1346 }
1347 
1348 static const struct got_error *
1349 open_blob(struct got_blob_object **blob, struct got_repository *repo,
1350     struct got_object_id *id, size_t blocksize, int outfd)
1351 {
1352 	const struct got_error *err = NULL;
1353 	struct got_packidx *packidx = NULL;
1354 	int idx, dfd = -1;
1355 	char *path_packfile = NULL;
1356 	uint8_t *outbuf;
1357 	size_t size, hdrlen;
1358 	struct stat sb;
1359 
1360 	*blob = calloc(1, sizeof(**blob));
1361 	if (*blob == NULL)
1362 		return got_error_from_errno("calloc");
1363 
1364 	(*blob)->read_buf = malloc(blocksize);
1365 	if ((*blob)->read_buf == NULL) {
1366 		err = got_error_from_errno("malloc");
1367 		goto done;
1368 	}
1369 
1370 	if (ftruncate(outfd, 0L) == -1) {
1371 		err = got_error_from_errno("ftruncate");
1372 		goto done;
1373 	}
1374 	if (lseek(outfd, SEEK_SET, 0) == -1) {
1375 		err = got_error_from_errno("lseek");
1376 		goto done;
1377 	}
1378 
1379 	err = got_repo_search_packidx(&packidx, &idx, repo, id);
1380 	if (err == NULL) {
1381 		struct got_pack *pack = NULL;
1382 
1383 		err = got_packidx_get_packfile_path(&path_packfile,
1384 		    packidx->path_packidx);
1385 		if (err)
1386 			goto done;
1387 
1388 		pack = got_repo_get_cached_pack(repo, path_packfile);
1389 		if (pack == NULL) {
1390 			err = got_repo_cache_pack(&pack, repo, path_packfile,
1391 			    packidx);
1392 			if (err)
1393 				goto done;
1394 		}
1395 		err = read_packed_blob_privsep(&outbuf, &size, &hdrlen, outfd,
1396 		    pack, packidx, idx, id);
1397 	} else if (err->code == GOT_ERR_NO_OBJ) {
1398 		int infd;
1399 
1400 		err = got_object_open_loose_fd(&infd, id, repo);
1401 		if (err)
1402 			goto done;
1403 		err = read_blob_privsep(&outbuf, &size, &hdrlen, outfd, infd,
1404 		    id, repo);
1405 	}
1406 	if (err)
1407 		goto done;
1408 
1409 	if (hdrlen > size) {
1410 		err = got_error(GOT_ERR_BAD_OBJ_HDR);
1411 		goto done;
1412 	}
1413 
1414 	if (outbuf) {
1415 		(*blob)->f = fmemopen(outbuf, size, "rb");
1416 		if ((*blob)->f == NULL) {
1417 			err = got_error_from_errno("fmemopen");
1418 			free(outbuf);
1419 			goto done;
1420 		}
1421 		(*blob)->data = outbuf;
1422 	} else {
1423 		if (fstat(outfd, &sb) == -1) {
1424 			err = got_error_from_errno("fstat");
1425 			goto done;
1426 		}
1427 
1428 		if (sb.st_size != size) {
1429 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1430 			goto done;
1431 		}
1432 
1433 		dfd = dup(outfd);
1434 		if (dfd == -1) {
1435 			err = got_error_from_errno("dup");
1436 			goto done;
1437 		}
1438 
1439 		(*blob)->f = fdopen(dfd, "rb");
1440 		if ((*blob)->f == NULL) {
1441 			err = got_error_from_errno("fdopen");
1442 			close(dfd);
1443 			dfd = -1;
1444 			goto done;
1445 		}
1446 	}
1447 
1448 	(*blob)->hdrlen = hdrlen;
1449 	(*blob)->blocksize = blocksize;
1450 	memcpy(&(*blob)->id.sha1, id->sha1, SHA1_DIGEST_LENGTH);
1451 
1452 done:
1453 	free(path_packfile);
1454 	if (err) {
1455 		if (*blob) {
1456 			got_object_blob_close(*blob);
1457 			*blob = NULL;
1458 		}
1459 	}
1460 	return err;
1461 }
1462 
1463 const struct got_error *
1464 got_object_open_as_blob(struct got_blob_object **blob,
1465     struct got_repository *repo, struct got_object_id *id, size_t blocksize,
1466     int outfd)
1467 {
1468 	return open_blob(blob, repo, id, blocksize, outfd);
1469 }
1470 
1471 const struct got_error *
1472 got_object_blob_open(struct got_blob_object **blob,
1473     struct got_repository *repo, struct got_object *obj, size_t blocksize,
1474     int outfd)
1475 {
1476 	return open_blob(blob, repo, got_object_get_id(obj), blocksize, outfd);
1477 }
1478 
1479 const struct got_error *
1480 got_object_blob_close(struct got_blob_object *blob)
1481 {
1482 	const struct got_error *err = NULL;
1483 	free(blob->read_buf);
1484 	if (blob->f && fclose(blob->f) == EOF)
1485 		err = got_error_from_errno("fclose");
1486 	free(blob->data);
1487 	free(blob);
1488 	return err;
1489 }
1490 
1491 void
1492 got_object_blob_rewind(struct got_blob_object *blob)
1493 {
1494 	if (blob->f)
1495 		rewind(blob->f);
1496 }
1497 
1498 char *
1499 got_object_blob_id_str(struct got_blob_object *blob, char *buf, size_t size)
1500 {
1501 	return got_sha1_digest_to_str(blob->id.sha1, buf, size);
1502 }
1503 
1504 size_t
1505 got_object_blob_get_hdrlen(struct got_blob_object *blob)
1506 {
1507 	return blob->hdrlen;
1508 }
1509 
1510 const uint8_t *
1511 got_object_blob_get_read_buf(struct got_blob_object *blob)
1512 {
1513 	return blob->read_buf;
1514 }
1515 
1516 const struct got_error *
1517 got_object_blob_read_block(size_t *outlenp, struct got_blob_object *blob)
1518 {
1519 	size_t n;
1520 
1521 	n = fread(blob->read_buf, 1, blob->blocksize, blob->f);
1522 	if (n == 0 && ferror(blob->f))
1523 		return got_ferror(blob->f, GOT_ERR_IO);
1524 	*outlenp = n;
1525 	return NULL;
1526 }
1527 
1528 const struct got_error *
1529 got_object_blob_dump_to_file(off_t *filesize, int *nlines,
1530     off_t **line_offsets, FILE *outfile, struct got_blob_object *blob)
1531 {
1532 	const struct got_error *err = NULL;
1533 	size_t n, len, hdrlen;
1534 	const uint8_t *buf;
1535 	int i;
1536 	const int alloc_chunksz = 512;
1537 	size_t nalloc = 0;
1538 	off_t off = 0, total_len = 0;
1539 
1540 	if (line_offsets)
1541 		*line_offsets = NULL;
1542 	if (filesize)
1543 		*filesize = 0;
1544 	if (nlines)
1545 		*nlines = 0;
1546 
1547 	hdrlen = got_object_blob_get_hdrlen(blob);
1548 	do {
1549 		err = got_object_blob_read_block(&len, blob);
1550 		if (err)
1551 			return err;
1552 		if (len == 0)
1553 			break;
1554 		buf = got_object_blob_get_read_buf(blob);
1555 		i = hdrlen;
1556 		if (nlines) {
1557 			if (line_offsets && *line_offsets == NULL) {
1558 				/* Have some data but perhaps no '\n'. */
1559 				*nlines = 1;
1560 				nalloc = alloc_chunksz;
1561 				*line_offsets = calloc(nalloc,
1562 				    sizeof(**line_offsets));
1563 				if (*line_offsets == NULL)
1564 					return got_error_from_errno("calloc");
1565 
1566 				/* Skip forward over end of first line. */
1567 				while (i < len) {
1568 					if (buf[i] == '\n')
1569 						break;
1570 					i++;
1571 				}
1572 			}
1573 			/* Scan '\n' offsets in remaining chunk of data. */
1574 			while (i < len) {
1575 				if (buf[i] != '\n') {
1576 					i++;
1577 					continue;
1578 				}
1579 				(*nlines)++;
1580 				if (line_offsets && nalloc < *nlines) {
1581 					size_t n = *nlines + alloc_chunksz;
1582 					off_t *o = recallocarray(*line_offsets,
1583 					    nalloc, n, sizeof(**line_offsets));
1584 					if (o == NULL) {
1585 						free(*line_offsets);
1586 						*line_offsets = NULL;
1587 						return got_error_from_errno(
1588 						    "recallocarray");
1589 					}
1590 					*line_offsets = o;
1591 					nalloc = n;
1592 				}
1593 				if (line_offsets) {
1594 					off = total_len + i - hdrlen + 1;
1595 					(*line_offsets)[*nlines - 1] = off;
1596 				}
1597 				i++;
1598 			}
1599 		}
1600 		/* Skip blob object header first time around. */
1601 		n = fwrite(buf + hdrlen, 1, len - hdrlen, outfile);
1602 		if (n != len - hdrlen)
1603 			return got_ferror(outfile, GOT_ERR_IO);
1604 		total_len += len - hdrlen;
1605 		hdrlen = 0;
1606 	} while (len != 0);
1607 
1608 	if (fflush(outfile) != 0)
1609 		return got_error_from_errno("fflush");
1610 	rewind(outfile);
1611 
1612 	if (filesize)
1613 		*filesize = total_len;
1614 
1615 	return NULL;
1616 }
1617 
1618 static const struct got_error *
1619 request_packed_tag(struct got_tag_object **tag, struct got_pack *pack,
1620     int pack_idx, struct got_object_id *id)
1621 {
1622 	const struct got_error *err = NULL;
1623 
1624 	err = got_privsep_send_tag_req(pack->privsep_child->ibuf, -1, id,
1625 	    pack_idx);
1626 	if (err)
1627 		return err;
1628 
1629 	return got_privsep_recv_tag(tag, pack->privsep_child->ibuf);
1630 }
1631 
1632 static const struct got_error *
1633 read_packed_tag_privsep(struct got_tag_object **tag,
1634     struct got_pack *pack, struct got_packidx *packidx, int idx,
1635     struct got_object_id *id)
1636 {
1637 	const struct got_error *err = NULL;
1638 
1639 	if (pack->privsep_child)
1640 		return request_packed_tag(tag, pack, idx, id);
1641 
1642 	err = got_pack_start_privsep_child(pack, packidx);
1643 	if (err)
1644 		return err;
1645 
1646 	return request_packed_tag(tag, pack, idx, id);
1647 }
1648 
1649 static const struct got_error *
1650 request_tag(struct got_tag_object **tag, struct got_repository *repo,
1651     int fd, struct got_object_id *id)
1652 {
1653 	const struct got_error *err = NULL;
1654 	struct imsgbuf *ibuf;
1655 
1656 	ibuf = repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_TAG].ibuf;
1657 
1658 	err = got_privsep_send_tag_req(ibuf, fd, id, -1);
1659 	if (err)
1660 		return err;
1661 
1662 	return got_privsep_recv_tag(tag, ibuf);
1663 }
1664 
1665 static const struct got_error *
1666 read_tag_privsep(struct got_tag_object **tag, int obj_fd,
1667     struct got_object_id *id, struct got_repository *repo)
1668 {
1669 	const struct got_error *err;
1670 	int imsg_fds[2];
1671 	pid_t pid;
1672 	struct imsgbuf *ibuf;
1673 
1674 	if (repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_TAG].imsg_fd != -1)
1675 		return request_tag(tag, repo, obj_fd, id);
1676 
1677 	ibuf = calloc(1, sizeof(*ibuf));
1678 	if (ibuf == NULL)
1679 		return got_error_from_errno("calloc");
1680 
1681 	if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, imsg_fds) == -1) {
1682 		err = got_error_from_errno("socketpair");
1683 		free(ibuf);
1684 		return err;
1685 	}
1686 
1687 	pid = fork();
1688 	if (pid == -1) {
1689 		err = got_error_from_errno("fork");
1690 		free(ibuf);
1691 		return err;
1692 	}
1693 	else if (pid == 0) {
1694 		got_privsep_exec_child(imsg_fds, GOT_PATH_PROG_READ_TAG,
1695 		    repo->path);
1696 		/* not reached */
1697 	}
1698 
1699 	if (close(imsg_fds[1]) == -1) {
1700 		err = got_error_from_errno("close");
1701 		free(ibuf);
1702 		return err;
1703 	}
1704 	repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_TAG].imsg_fd =
1705 	    imsg_fds[0];
1706 	repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_TAG].pid = pid;
1707 	imsg_init(ibuf, imsg_fds[0]);
1708 	repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_TAG].ibuf = ibuf;
1709 
1710 	return request_tag(tag, repo, obj_fd, id);
1711 }
1712 
1713 static const struct got_error *
1714 open_tag(struct got_tag_object **tag, struct got_repository *repo,
1715     struct got_object_id *id, int check_cache)
1716 {
1717 	const struct got_error *err = NULL;
1718 	struct got_packidx *packidx = NULL;
1719 	int idx;
1720 	char *path_packfile = NULL;
1721 	struct got_object *obj = NULL;
1722 	int obj_type = GOT_OBJ_TYPE_ANY;
1723 
1724 	if (check_cache) {
1725 		*tag = got_repo_get_cached_tag(repo, id);
1726 		if (*tag != NULL) {
1727 			(*tag)->refcnt++;
1728 			return NULL;
1729 		}
1730 	} else
1731 		*tag = NULL;
1732 
1733 	err = got_repo_search_packidx(&packidx, &idx, repo, id);
1734 	if (err == NULL) {
1735 		struct got_pack *pack = NULL;
1736 
1737 		err = got_packidx_get_packfile_path(&path_packfile,
1738 		    packidx->path_packidx);
1739 		if (err)
1740 			return err;
1741 
1742 		pack = got_repo_get_cached_pack(repo, path_packfile);
1743 		if (pack == NULL) {
1744 			err = got_repo_cache_pack(&pack, repo, path_packfile,
1745 			    packidx);
1746 			if (err)
1747 				goto done;
1748 		}
1749 
1750 		/* Beware of "lightweight" tags: Check object type first. */
1751 		err = read_packed_object_privsep(&obj, repo, pack, packidx,
1752 		    idx, id);
1753 		if (err)
1754 			goto done;
1755 		obj_type = obj->type;
1756 		got_object_close(obj);
1757 		if (obj_type != GOT_OBJ_TYPE_TAG) {
1758 			err = got_error(GOT_ERR_OBJ_TYPE);
1759 			goto done;
1760 		}
1761 		err = read_packed_tag_privsep(tag, pack, packidx, idx, id);
1762 	} else if (err->code == GOT_ERR_NO_OBJ) {
1763 		int fd;
1764 
1765 		err = got_object_open_loose_fd(&fd, id, repo);
1766 		if (err)
1767 			return err;
1768 		err = got_object_read_header_privsep(&obj, id, repo, fd);
1769 		if (err)
1770 			return err;
1771 		obj_type = obj->type;
1772 		got_object_close(obj);
1773 		if (obj_type != GOT_OBJ_TYPE_TAG)
1774 			return got_error(GOT_ERR_OBJ_TYPE);
1775 
1776 		err = got_object_open_loose_fd(&fd, id, repo);
1777 		if (err)
1778 			return err;
1779 		err = read_tag_privsep(tag, fd, id, repo);
1780 	}
1781 
1782 	if (err == NULL) {
1783 		(*tag)->refcnt++;
1784 		err = got_repo_cache_tag(repo, id, *tag);
1785 	}
1786 done:
1787 	free(path_packfile);
1788 	return err;
1789 }
1790 
1791 const struct got_error *
1792 got_object_open_as_tag(struct got_tag_object **tag,
1793     struct got_repository *repo, struct got_object_id *id)
1794 {
1795 	*tag = got_repo_get_cached_tag(repo, id);
1796 	if (*tag != NULL) {
1797 		(*tag)->refcnt++;
1798 		return NULL;
1799 	}
1800 
1801 	return open_tag(tag, repo, id, 0);
1802 }
1803 
1804 const struct got_error *
1805 got_object_tag_open(struct got_tag_object **tag,
1806     struct got_repository *repo, struct got_object *obj)
1807 {
1808 	return open_tag(tag, repo, got_object_get_id(obj), 1);
1809 }
1810 
1811 const char *
1812 got_object_tag_get_name(struct got_tag_object *tag)
1813 {
1814 	return tag->tag;
1815 }
1816 
1817 int
1818 got_object_tag_get_object_type(struct got_tag_object *tag)
1819 {
1820 	return tag->obj_type;
1821 }
1822 
1823 struct got_object_id *
1824 got_object_tag_get_object_id(struct got_tag_object *tag)
1825 {
1826 	return &tag->id;
1827 }
1828 
1829 time_t
1830 got_object_tag_get_tagger_time(struct got_tag_object *tag)
1831 {
1832 	return tag->tagger_time;
1833 }
1834 
1835 time_t
1836 got_object_tag_get_tagger_gmtoff(struct got_tag_object *tag)
1837 {
1838 	return tag->tagger_gmtoff;
1839 }
1840 
1841 const char *
1842 got_object_tag_get_tagger(struct got_tag_object *tag)
1843 {
1844 	return tag->tagger;
1845 }
1846 
1847 const char *
1848 got_object_tag_get_message(struct got_tag_object *tag)
1849 {
1850 	return tag->tagmsg;
1851 }
1852 
1853 static struct got_tree_entry *
1854 find_entry_by_name(struct got_tree_object *tree, const char *name, size_t len)
1855 {
1856 	int i;
1857 
1858 	/* Note that tree entries are sorted in strncmp() order. */
1859 	for (i = 0; i < tree->nentries; i++) {
1860 		struct got_tree_entry *te = &tree->entries[i];
1861 		int cmp = strncmp(te->name, name, len);
1862 		if (cmp < 0)
1863 			continue;
1864 		if (cmp > 0)
1865 			break;
1866 		if (te->name[len] == '\0')
1867 			return te;
1868 	}
1869 	return NULL;
1870 }
1871 
1872 struct got_tree_entry *
1873 got_object_tree_find_entry(struct got_tree_object *tree, const char *name)
1874 {
1875 	return find_entry_by_name(tree, name, strlen(name));
1876 }
1877 
1878 const struct got_error *
1879 got_object_tree_find_path(struct got_object_id **id, mode_t *mode,
1880     struct got_repository *repo, struct got_tree_object *tree,
1881     const char *path)
1882 {
1883 	const struct got_error *err = NULL;
1884 	struct got_tree_object *subtree = NULL;
1885 	struct got_tree_entry *te = NULL;
1886 	const char *seg, *s;
1887 	size_t seglen;
1888 
1889 	*id = NULL;
1890 
1891 	s = path;
1892 	while (s[0] == '/')
1893 		s++;
1894 	seg = s;
1895 	seglen = 0;
1896 	subtree = tree;
1897 	while (*s) {
1898 		struct got_tree_object *next_tree;
1899 
1900 		if (*s != '/') {
1901 			s++;
1902 			seglen++;
1903 			if (*s)
1904 				continue;
1905 		}
1906 
1907 		te = find_entry_by_name(subtree, seg, seglen);
1908 		if (te == NULL) {
1909 			err = got_error_path(path, GOT_ERR_NO_TREE_ENTRY);
1910 			goto done;
1911 		}
1912 
1913 		if (*s == '\0')
1914 			break;
1915 
1916 		seg = s + 1;
1917 		seglen = 0;
1918 		s++;
1919 		if (*s) {
1920 			err = got_object_open_as_tree(&next_tree, repo,
1921 			    &te->id);
1922 			te = NULL;
1923 			if (err)
1924 				goto done;
1925 			if (subtree != tree)
1926 				got_object_tree_close(subtree);
1927 			subtree = next_tree;
1928 		}
1929 	}
1930 
1931 	if (te) {
1932 		*id = got_object_id_dup(&te->id);
1933 		if (*id == NULL)
1934 			return got_error_from_errno("got_object_id_dup");
1935 		if (mode)
1936 			*mode = te->mode;
1937 	} else
1938 		err = got_error_path(path, GOT_ERR_NO_TREE_ENTRY);
1939 done:
1940 	if (subtree && subtree != tree)
1941 		got_object_tree_close(subtree);
1942 	return err;
1943 }
1944 const struct got_error *
1945 got_object_id_by_path(struct got_object_id **id, struct got_repository *repo,
1946     struct got_commit_object *commit, const char *path)
1947 {
1948 	const struct got_error *err = NULL;
1949 	struct got_tree_object *tree = NULL;
1950 
1951 	*id = NULL;
1952 
1953 	/* Handle opening of root of commit's tree. */
1954 	if (got_path_is_root_dir(path)) {
1955 		*id = got_object_id_dup(commit->tree_id);
1956 		if (*id == NULL)
1957 			err = got_error_from_errno("got_object_id_dup");
1958 	} else {
1959 		err = got_object_open_as_tree(&tree, repo, commit->tree_id);
1960 		if (err)
1961 			goto done;
1962 		err = got_object_tree_find_path(id, NULL, repo, tree, path);
1963 	}
1964 done:
1965 	if (tree)
1966 		got_object_tree_close(tree);
1967 	return err;
1968 }
1969 
1970 /*
1971  * Normalize file mode bits to avoid false positive tree entry differences
1972  * in case tree entries have unexpected mode bits set.
1973  */
1974 static mode_t
1975 normalize_mode_for_comparison(mode_t mode)
1976 {
1977 	/*
1978 	 * For directories, the only relevant bit is the IFDIR bit.
1979 	 * This allows us to detect paths changing from a directory
1980 	 * to a file and vice versa.
1981 	 */
1982 	if (S_ISDIR(mode))
1983 		return mode & S_IFDIR;
1984 
1985 	/*
1986 	 * For symlinks, the only relevant bit is the IFLNK bit.
1987 	 * This allows us to detect paths changing from a symlinks
1988 	 * to a file or directory and vice versa.
1989 	 */
1990 	if (S_ISLNK(mode))
1991 		return mode & S_IFLNK;
1992 
1993 	/* For files, the only change we care about is the executable bit. */
1994 	return mode & S_IXUSR;
1995 }
1996 
1997 const struct got_error *
1998 got_object_tree_path_changed(int *changed,
1999     struct got_tree_object *tree01, struct got_tree_object *tree02,
2000     const char *path, struct got_repository *repo)
2001 {
2002 	const struct got_error *err = NULL;
2003 	struct got_tree_object *tree1 = NULL, *tree2 = NULL;
2004 	struct got_tree_entry *te1 = NULL, *te2 = NULL;
2005 	const char *seg, *s;
2006 	size_t seglen;
2007 
2008 	*changed = 0;
2009 
2010 	/* We not do support comparing the root path. */
2011 	if (got_path_is_root_dir(path))
2012 		return got_error_path(path, GOT_ERR_BAD_PATH);
2013 
2014 	tree1 = tree01;
2015 	tree2 = tree02;
2016 	s = path;
2017 	while (*s == '/')
2018 		s++;
2019 	seg = s;
2020 	seglen = 0;
2021 	while (*s) {
2022 		struct got_tree_object *next_tree1, *next_tree2;
2023 		mode_t mode1, mode2;
2024 
2025 		if (*s != '/') {
2026 			s++;
2027 			seglen++;
2028 			if (*s)
2029 				continue;
2030 		}
2031 
2032 		te1 = find_entry_by_name(tree1, seg, seglen);
2033 		if (te1 == NULL) {
2034 			err = got_error(GOT_ERR_NO_OBJ);
2035 			goto done;
2036 		}
2037 
2038 		if (tree2)
2039 			te2 = find_entry_by_name(tree2, seg, seglen);
2040 
2041 		if (te2) {
2042 			mode1 = normalize_mode_for_comparison(te1->mode);
2043 			mode2 = normalize_mode_for_comparison(te2->mode);
2044 			if (mode1 != mode2) {
2045 				*changed = 1;
2046 				goto done;
2047 			}
2048 
2049 			if (got_object_id_cmp(&te1->id, &te2->id) == 0) {
2050 				*changed = 0;
2051 				goto done;
2052 			}
2053 		}
2054 
2055 		if (*s == '\0') { /* final path element */
2056 			*changed = 1;
2057 			goto done;
2058 		}
2059 
2060 		seg = s + 1;
2061 		s++;
2062 		seglen = 0;
2063 		if (*s) {
2064 			err = got_object_open_as_tree(&next_tree1, repo,
2065 			    &te1->id);
2066 			te1 = NULL;
2067 			if (err)
2068 				goto done;
2069 			if (tree1 != tree01)
2070 				got_object_tree_close(tree1);
2071 			tree1 = next_tree1;
2072 
2073 			if (te2) {
2074 				err = got_object_open_as_tree(&next_tree2, repo,
2075 				    &te2->id);
2076 				te2 = NULL;
2077 				if (err)
2078 					goto done;
2079 				if (tree2 != tree02)
2080 					got_object_tree_close(tree2);
2081 				tree2 = next_tree2;
2082 			} else if (tree2) {
2083 				if (tree2 != tree02)
2084 					got_object_tree_close(tree2);
2085 				tree2 = NULL;
2086 			}
2087 		}
2088 	}
2089 done:
2090 	if (tree1 && tree1 != tree01)
2091 		got_object_tree_close(tree1);
2092 	if (tree2 && tree2 != tree02)
2093 		got_object_tree_close(tree2);
2094 	return err;
2095 }
2096 
2097 const struct got_error *
2098 got_object_tree_entry_dup(struct got_tree_entry **new_te,
2099     struct got_tree_entry *te)
2100 {
2101 	const struct got_error *err = NULL;
2102 
2103 	*new_te = calloc(1, sizeof(**new_te));
2104 	if (*new_te == NULL)
2105 		return got_error_from_errno("calloc");
2106 
2107 	(*new_te)->mode = te->mode;
2108 	memcpy((*new_te)->name, te->name, sizeof((*new_te)->name));
2109 	memcpy(&(*new_te)->id, &te->id, sizeof((*new_te)->id));
2110 	return err;
2111 }
2112 
2113 int
2114 got_object_tree_entry_is_submodule(struct got_tree_entry *te)
2115 {
2116 	return (te->mode & S_IFMT) == (S_IFDIR | S_IFLNK);
2117 }
2118 
2119 int
2120 got_object_tree_entry_is_symlink(struct got_tree_entry *te)
2121 {
2122 	/* S_IFDIR check avoids confusing symlinks with submodules. */
2123 	return ((te->mode & (S_IFDIR | S_IFLNK)) == S_IFLNK);
2124 }
2125 
2126 static const struct got_error *
2127 resolve_symlink(char **link_target, const char *path,
2128     struct got_commit_object *commit, struct got_repository *repo)
2129 {
2130 	const struct got_error *err = NULL;
2131 	char buf[PATH_MAX];
2132 	char *name, *parent_path = NULL;
2133 	struct got_object_id *tree_obj_id = NULL;
2134 	struct got_tree_object *tree = NULL;
2135 	struct got_tree_entry *te = NULL;
2136 
2137 	*link_target = NULL;
2138 
2139 	if (strlcpy(buf, path, sizeof(buf)) >= sizeof(buf))
2140 		return got_error(GOT_ERR_NO_SPACE);
2141 
2142 	name = basename(buf);
2143 	if (name == NULL)
2144 		return got_error_from_errno2("basename", path);
2145 
2146 	err = got_path_dirname(&parent_path, path);
2147 	if (err)
2148 		return err;
2149 
2150 	err = got_object_id_by_path(&tree_obj_id, repo, commit,
2151 	    parent_path);
2152 	if (err) {
2153 		if (err->code == GOT_ERR_NO_TREE_ENTRY) {
2154 			/* Display the complete path in error message. */
2155 			err = got_error_path(path, err->code);
2156 		}
2157 		goto done;
2158 	}
2159 
2160 	err = got_object_open_as_tree(&tree, repo, tree_obj_id);
2161 	if (err)
2162 		goto done;
2163 
2164 	te = got_object_tree_find_entry(tree, name);
2165 	if (te == NULL) {
2166 		err = got_error_path(path, GOT_ERR_NO_TREE_ENTRY);
2167 		goto done;
2168 	}
2169 
2170 	if (got_object_tree_entry_is_symlink(te)) {
2171 		err = got_tree_entry_get_symlink_target(link_target, te, repo);
2172 		if (err)
2173 			goto done;
2174 		if (!got_path_is_absolute(*link_target)) {
2175 			char *abspath;
2176 			if (asprintf(&abspath, "%s/%s", parent_path,
2177 			    *link_target) == -1) {
2178 				err = got_error_from_errno("asprintf");
2179 				goto done;
2180 			}
2181 			free(*link_target);
2182 			*link_target = malloc(PATH_MAX);
2183 			if (*link_target == NULL) {
2184 				err = got_error_from_errno("malloc");
2185 				goto done;
2186 			}
2187 			err = got_canonpath(abspath, *link_target, PATH_MAX);
2188 			free(abspath);
2189 			if (err)
2190 				goto done;
2191 		}
2192 	}
2193 done:
2194 	free(parent_path);
2195 	free(tree_obj_id);
2196 	if (tree)
2197 		got_object_tree_close(tree);
2198 	if (err) {
2199 		free(*link_target);
2200 		*link_target = NULL;
2201 	}
2202 	return err;
2203 }
2204 
2205 const struct got_error *
2206 got_object_resolve_symlinks(char **link_target, const char *path,
2207     struct got_commit_object *commit, struct got_repository *repo)
2208 {
2209 	const struct got_error *err = NULL;
2210 	char *next_target = NULL;
2211 	int max_recursion = 40; /* matches Git */
2212 
2213 	*link_target = NULL;
2214 
2215 	do {
2216 		err = resolve_symlink(&next_target,
2217 		    *link_target ? *link_target : path, commit, repo);
2218 		if (err)
2219 			break;
2220 		if (next_target) {
2221 			free(*link_target);
2222 			if (--max_recursion == 0) {
2223 				err = got_error_path(path, GOT_ERR_RECURSION);
2224 				*link_target = NULL;
2225 				break;
2226 			}
2227 			*link_target = next_target;
2228 		}
2229 	} while (next_target);
2230 
2231 	return err;
2232 }
2233 
2234 const struct got_error *
2235 got_traverse_packed_commits(struct got_object_id_queue *traversed_commits,
2236     struct got_object_id *commit_id, const char *path,
2237     struct got_repository *repo)
2238 {
2239 	const struct got_error *err = NULL;
2240 	struct got_pack *pack = NULL;
2241 	struct got_packidx *packidx = NULL;
2242 	char *path_packfile = NULL;
2243 	struct got_commit_object *changed_commit = NULL;
2244 	struct got_object_id *changed_commit_id = NULL;
2245 	int idx;
2246 
2247 	err = got_repo_search_packidx(&packidx, &idx, repo, commit_id);
2248 	if (err) {
2249 		if (err->code != GOT_ERR_NO_OBJ)
2250 			return err;
2251 		return NULL;
2252 	}
2253 
2254 	err = got_packidx_get_packfile_path(&path_packfile,
2255 	    packidx->path_packidx);
2256 	if (err)
2257 		return err;
2258 
2259 	pack = got_repo_get_cached_pack(repo, path_packfile);
2260 	if (pack == NULL) {
2261 		err = got_repo_cache_pack(&pack, repo, path_packfile, packidx);
2262 		if (err)
2263 			goto done;
2264 	}
2265 
2266 	if (pack->privsep_child == NULL) {
2267 		err = got_pack_start_privsep_child(pack, packidx);
2268 		if (err)
2269 			goto done;
2270 	}
2271 
2272 	err = got_privsep_send_commit_traversal_request(
2273 	    pack->privsep_child->ibuf, commit_id, idx, path);
2274 	if (err)
2275 		goto done;
2276 
2277 	err = got_privsep_recv_traversed_commits(&changed_commit,
2278 	    &changed_commit_id, traversed_commits, pack->privsep_child->ibuf);
2279 	if (err)
2280 		goto done;
2281 
2282 	if (changed_commit) {
2283 		/*
2284 		 * Cache the commit in which the path was changed.
2285 		 * This commit might be opened again soon.
2286 		 */
2287 		changed_commit->refcnt++;
2288 		err = got_repo_cache_commit(repo, changed_commit_id,
2289 		    changed_commit);
2290 		got_object_commit_close(changed_commit);
2291 	}
2292 done:
2293 	free(path_packfile);
2294 	free(changed_commit_id);
2295 	return err;
2296 }
2297 
2298 const struct got_error *
2299 got_object_enumerate(int *found_all_objects,
2300     got_object_enumerate_commit_cb cb_commit,
2301     got_object_enumerate_tree_cb cb_tree, void *cb_arg,
2302     struct got_object_id **ours, int nours,
2303     struct got_object_id **theirs, int ntheirs,
2304     struct got_packidx *packidx, struct got_repository *repo)
2305 {
2306 	const struct got_error *err = NULL;
2307 	struct got_pack *pack;
2308 	char *path_packfile = NULL;
2309 
2310 	err = got_packidx_get_packfile_path(&path_packfile,
2311 	    packidx->path_packidx);
2312 	if (err)
2313 		return err;
2314 
2315 	pack = got_repo_get_cached_pack(repo, path_packfile);
2316 	if (pack == NULL) {
2317 		err = got_repo_cache_pack(&pack, repo, path_packfile, packidx);
2318 		if (err)
2319 			goto done;
2320 	}
2321 
2322 	if (pack->privsep_child == NULL) {
2323 		err = got_pack_start_privsep_child(pack, packidx);
2324 		if (err)
2325 			goto done;
2326 	}
2327 
2328 	err = got_privsep_send_object_enumeration_request(
2329 	    pack->privsep_child->ibuf);
2330 	if (err)
2331 		goto done;
2332 
2333 	err = got_privsep_send_object_idlist(pack->privsep_child->ibuf,
2334 	    ours, nours);
2335 	if (err)
2336 		goto done;
2337 	err = got_privsep_send_object_idlist_done(pack->privsep_child->ibuf);
2338 	if (err)
2339 		goto done;
2340 
2341 	err = got_privsep_send_object_idlist(pack->privsep_child->ibuf,
2342 	    theirs, ntheirs);
2343 	if (err)
2344 		goto done;
2345 	err = got_privsep_send_object_idlist_done(pack->privsep_child->ibuf);
2346 	if (err)
2347 		goto done;
2348 
2349 	err = got_privsep_recv_enumerated_objects(found_all_objects,
2350 	    pack->privsep_child->ibuf, cb_commit, cb_tree, cb_arg, repo);
2351 done:
2352 	free(path_packfile);
2353 	return err;
2354 }
2355 
2356 void
2357 got_object_commit_retain(struct got_commit_object *commit)
2358 {
2359 	commit->refcnt++;
2360 }