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