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 
1162 	*link_target = NULL;
1163 
1164 	if (!got_object_tree_entry_is_symlink(te))
1165 		return got_error(GOT_ERR_TREE_ENTRY_TYPE);
1166 
1167 	err = got_object_open_as_blob(&blob, repo,
1168 	    got_tree_entry_get_id(te), PATH_MAX);
1169 	if (err)
1170 		return err;
1171 
1172 	err = got_object_blob_read_to_str(link_target, blob);
1173 	got_object_blob_close(blob);
1174 	if (err) {
1175 		free(*link_target);
1176 		*link_target = NULL;
1177 	}
1178 	return err;
1179 }
1180 
1181 int
1182 got_tree_entry_get_index(struct got_tree_entry *te)
1183 {
1184 	return te->idx;
1185 }
1186 
1187 struct got_tree_entry *
1188 got_tree_entry_get_next(struct got_tree_object *tree,
1189     struct got_tree_entry *te)
1190 {
1191 	return got_object_tree_get_entry(tree, te->idx + 1);
1192 }
1193 
1194 struct got_tree_entry *
1195 got_tree_entry_get_prev(struct got_tree_object *tree,
1196     struct got_tree_entry *te)
1197 {
1198 	return got_object_tree_get_entry(tree, te->idx - 1);
1199 }
1200 
1201 static const struct got_error *
1202 request_packed_blob(uint8_t **outbuf, size_t *size, size_t *hdrlen, int outfd,
1203     struct got_pack *pack, struct got_packidx *packidx, int idx,
1204     struct got_object_id *id)
1205 {
1206 	const struct got_error *err = NULL;
1207 	struct imsgbuf *ibuf = pack->privsep_child->ibuf;
1208 	int outfd_child;
1209 
1210 	 err = pack_child_send_tempfiles(ibuf, pack);
1211 	 if (err)
1212 		return err;
1213 
1214 	outfd_child = dup(outfd);
1215 	if (outfd_child == -1)
1216 		return got_error_from_errno("dup");
1217 
1218 	err = got_privsep_send_blob_req(pack->privsep_child->ibuf, -1, id, idx);
1219 	if (err)
1220 		return err;
1221 
1222 	err = got_privsep_send_blob_outfd(pack->privsep_child->ibuf,
1223 	    outfd_child);
1224 	if (err) {
1225 		return err;
1226 	}
1227 
1228 	err = got_privsep_recv_blob(outbuf, size, hdrlen,
1229 	    pack->privsep_child->ibuf);
1230 	if (err)
1231 		return err;
1232 
1233 	if (lseek(outfd, SEEK_SET, 0) == -1)
1234 		err = got_error_from_errno("lseek");
1235 
1236 	return err;
1237 }
1238 
1239 static const struct got_error *
1240 read_packed_blob_privsep(uint8_t **outbuf, size_t *size, size_t *hdrlen,
1241     int outfd, struct got_pack *pack, struct got_packidx *packidx, int idx,
1242     struct got_object_id *id)
1243 {
1244 	const struct got_error *err = NULL;
1245 
1246 	if (pack->privsep_child == NULL) {
1247 		err = got_pack_start_privsep_child(pack, packidx);
1248 		if (err)
1249 			return err;
1250 	}
1251 
1252 	return request_packed_blob(outbuf, size, hdrlen, outfd, pack, packidx,
1253 	    idx, id);
1254 }
1255 
1256 static const struct got_error *
1257 request_blob(uint8_t **outbuf, size_t *size, size_t *hdrlen, int outfd,
1258     int infd, struct got_object_id *id, struct imsgbuf *ibuf)
1259 {
1260 	const struct got_error *err = NULL;
1261 	int outfd_child;
1262 
1263 	outfd_child = dup(outfd);
1264 	if (outfd_child == -1)
1265 		return got_error_from_errno("dup");
1266 
1267 	err = got_privsep_send_blob_req(ibuf, infd, id, -1);
1268 	if (err)
1269 		return err;
1270 
1271 	err = got_privsep_send_blob_outfd(ibuf, outfd_child);
1272 	if (err)
1273 		return err;
1274 
1275 	err = got_privsep_recv_blob(outbuf, size, hdrlen, ibuf);
1276 	if (err)
1277 		return err;
1278 
1279 	if (lseek(outfd, SEEK_SET, 0) == -1)
1280 		return got_error_from_errno("lseek");
1281 
1282 	return err;
1283 }
1284 
1285 static const struct got_error *
1286 read_blob_privsep(uint8_t **outbuf, size_t *size, size_t *hdrlen,
1287     int outfd, int infd, struct got_object_id *id, struct got_repository *repo)
1288 {
1289 	const struct got_error *err;
1290 	int imsg_fds[2];
1291 	pid_t pid;
1292 	struct imsgbuf *ibuf;
1293 
1294 	if (repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_BLOB].imsg_fd != -1) {
1295 		ibuf = repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_BLOB].ibuf;
1296 		return request_blob(outbuf, size, hdrlen, outfd, infd, id,
1297 		    ibuf);
1298 	}
1299 
1300 	ibuf = calloc(1, sizeof(*ibuf));
1301 	if (ibuf == NULL)
1302 		return got_error_from_errno("calloc");
1303 
1304 	if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, imsg_fds) == -1) {
1305 		err = got_error_from_errno("socketpair");
1306 		free(ibuf);
1307 		return err;
1308 	}
1309 
1310 	pid = fork();
1311 	if (pid == -1) {
1312 		err = got_error_from_errno("fork");
1313 		free(ibuf);
1314 		return err;
1315 	}
1316 	else if (pid == 0) {
1317 		got_privsep_exec_child(imsg_fds, GOT_PATH_PROG_READ_BLOB,
1318 		    repo->path);
1319 		/* not reached */
1320 	}
1321 
1322 	if (close(imsg_fds[1]) == -1) {
1323 		err = got_error_from_errno("close");
1324 		free(ibuf);
1325 		return err;
1326 	}
1327 	repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_BLOB].imsg_fd =
1328 	    imsg_fds[0];
1329 	repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_BLOB].pid = pid;
1330 	imsg_init(ibuf, imsg_fds[0]);
1331 	repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_BLOB].ibuf = ibuf;
1332 
1333 	return request_blob(outbuf, size, hdrlen, outfd, infd, id, ibuf);
1334 }
1335 
1336 static const struct got_error *
1337 open_blob(struct got_blob_object **blob, struct got_repository *repo,
1338     struct got_object_id *id, size_t blocksize)
1339 {
1340 	const struct got_error *err = NULL;
1341 	struct got_packidx *packidx = NULL;
1342 	int idx;
1343 	char *path_packfile = NULL;
1344 	uint8_t *outbuf;
1345 	int outfd;
1346 	size_t size, hdrlen;
1347 	struct stat sb;
1348 
1349 	*blob = calloc(1, sizeof(**blob));
1350 	if (*blob == NULL)
1351 		return got_error_from_errno("calloc");
1352 
1353 	outfd = got_opentempfd();
1354 	if (outfd == -1)
1355 		return got_error_from_errno("got_opentempfd");
1356 
1357 	(*blob)->read_buf = malloc(blocksize);
1358 	if ((*blob)->read_buf == NULL) {
1359 		err = got_error_from_errno("malloc");
1360 		goto done;
1361 	}
1362 
1363 	err = got_repo_search_packidx(&packidx, &idx, repo, id);
1364 	if (err == NULL) {
1365 		struct got_pack *pack = NULL;
1366 
1367 		err = got_packidx_get_packfile_path(&path_packfile,
1368 		    packidx->path_packidx);
1369 		if (err)
1370 			goto done;
1371 
1372 		pack = got_repo_get_cached_pack(repo, path_packfile);
1373 		if (pack == NULL) {
1374 			err = got_repo_cache_pack(&pack, repo, path_packfile,
1375 			    packidx);
1376 			if (err)
1377 				goto done;
1378 		}
1379 		err = read_packed_blob_privsep(&outbuf, &size, &hdrlen, outfd,
1380 		    pack, packidx, idx, id);
1381 	} else if (err->code == GOT_ERR_NO_OBJ) {
1382 		int infd;
1383 
1384 		err = got_object_open_loose_fd(&infd, id, repo);
1385 		if (err)
1386 			goto done;
1387 		err = read_blob_privsep(&outbuf, &size, &hdrlen, outfd, infd,
1388 		    id, repo);
1389 	}
1390 	if (err)
1391 		goto done;
1392 
1393 	if (hdrlen > size) {
1394 		err = got_error(GOT_ERR_BAD_OBJ_HDR);
1395 		goto done;
1396 	}
1397 
1398 	if (outbuf) {
1399 		if (close(outfd) == -1 && err == NULL)
1400 			err = got_error_from_errno("close");
1401 		outfd = -1;
1402 		(*blob)->f = fmemopen(outbuf, size, "rb");
1403 		if ((*blob)->f == NULL) {
1404 			err = got_error_from_errno("fmemopen");
1405 			free(outbuf);
1406 			goto done;
1407 		}
1408 		(*blob)->data = outbuf;
1409 	} else {
1410 		if (fstat(outfd, &sb) == -1) {
1411 			err = got_error_from_errno("fstat");
1412 			goto done;
1413 		}
1414 
1415 		if (sb.st_size != size) {
1416 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1417 			goto done;
1418 		}
1419 
1420 		(*blob)->f = fdopen(outfd, "rb");
1421 		if ((*blob)->f == NULL) {
1422 			err = got_error_from_errno("fdopen");
1423 			close(outfd);
1424 			outfd = -1;
1425 			goto done;
1426 		}
1427 	}
1428 
1429 	(*blob)->hdrlen = hdrlen;
1430 	(*blob)->blocksize = blocksize;
1431 	memcpy(&(*blob)->id.sha1, id->sha1, SHA1_DIGEST_LENGTH);
1432 
1433 done:
1434 	free(path_packfile);
1435 	if (err) {
1436 		if (*blob) {
1437 			got_object_blob_close(*blob);
1438 			*blob = NULL;
1439 		} else if (outfd != -1)
1440 			close(outfd);
1441 	}
1442 	return err;
1443 }
1444 
1445 const struct got_error *
1446 got_object_open_as_blob(struct got_blob_object **blob,
1447     struct got_repository *repo, struct got_object_id *id,
1448     size_t blocksize)
1449 {
1450 	return open_blob(blob, repo, id, blocksize);
1451 }
1452 
1453 const struct got_error *
1454 got_object_blob_open(struct got_blob_object **blob,
1455     struct got_repository *repo, struct got_object *obj, size_t blocksize)
1456 {
1457 	return open_blob(blob, repo, got_object_get_id(obj), blocksize);
1458 }
1459 
1460 const struct got_error *
1461 got_object_blob_close(struct got_blob_object *blob)
1462 {
1463 	const struct got_error *err = NULL;
1464 	free(blob->read_buf);
1465 	if (blob->f && fclose(blob->f) == EOF)
1466 		err = got_error_from_errno("fclose");
1467 	free(blob->data);
1468 	free(blob);
1469 	return err;
1470 }
1471 
1472 void
1473 got_object_blob_rewind(struct got_blob_object *blob)
1474 {
1475 	if (blob->f)
1476 		rewind(blob->f);
1477 }
1478 
1479 char *
1480 got_object_blob_id_str(struct got_blob_object *blob, char *buf, size_t size)
1481 {
1482 	return got_sha1_digest_to_str(blob->id.sha1, buf, size);
1483 }
1484 
1485 size_t
1486 got_object_blob_get_hdrlen(struct got_blob_object *blob)
1487 {
1488 	return blob->hdrlen;
1489 }
1490 
1491 const uint8_t *
1492 got_object_blob_get_read_buf(struct got_blob_object *blob)
1493 {
1494 	return blob->read_buf;
1495 }
1496 
1497 const struct got_error *
1498 got_object_blob_read_block(size_t *outlenp, struct got_blob_object *blob)
1499 {
1500 	size_t n;
1501 
1502 	n = fread(blob->read_buf, 1, blob->blocksize, blob->f);
1503 	if (n == 0 && ferror(blob->f))
1504 		return got_ferror(blob->f, GOT_ERR_IO);
1505 	*outlenp = n;
1506 	return NULL;
1507 }
1508 
1509 const struct got_error *
1510 got_object_blob_dump_to_file(off_t *filesize, int *nlines,
1511     off_t **line_offsets, FILE *outfile, struct got_blob_object *blob)
1512 {
1513 	const struct got_error *err = NULL;
1514 	size_t n, len, hdrlen;
1515 	const uint8_t *buf;
1516 	int i;
1517 	const int alloc_chunksz = 512;
1518 	size_t nalloc = 0;
1519 	off_t off = 0, total_len = 0;
1520 
1521 	if (line_offsets)
1522 		*line_offsets = NULL;
1523 	if (filesize)
1524 		*filesize = 0;
1525 	if (nlines)
1526 		*nlines = 0;
1527 
1528 	hdrlen = got_object_blob_get_hdrlen(blob);
1529 	do {
1530 		err = got_object_blob_read_block(&len, blob);
1531 		if (err)
1532 			return err;
1533 		if (len == 0)
1534 			break;
1535 		buf = got_object_blob_get_read_buf(blob);
1536 		i = hdrlen;
1537 		if (nlines) {
1538 			if (line_offsets && *line_offsets == NULL) {
1539 				/* Have some data but perhaps no '\n'. */
1540 				*nlines = 1;
1541 				nalloc = alloc_chunksz;
1542 				*line_offsets = calloc(nalloc,
1543 				    sizeof(**line_offsets));
1544 				if (*line_offsets == NULL)
1545 					return got_error_from_errno("calloc");
1546 
1547 				/* Skip forward over end of first line. */
1548 				while (i < len) {
1549 					if (buf[i] == '\n')
1550 						break;
1551 					i++;
1552 				}
1553 			}
1554 			/* Scan '\n' offsets in remaining chunk of data. */
1555 			while (i < len) {
1556 				if (buf[i] != '\n') {
1557 					i++;
1558 					continue;
1559 				}
1560 				(*nlines)++;
1561 				if (line_offsets && nalloc < *nlines) {
1562 					size_t n = *nlines + alloc_chunksz;
1563 					off_t *o = recallocarray(*line_offsets,
1564 					    nalloc, n, sizeof(**line_offsets));
1565 					if (o == NULL) {
1566 						free(*line_offsets);
1567 						*line_offsets = NULL;
1568 						return got_error_from_errno(
1569 						    "recallocarray");
1570 					}
1571 					*line_offsets = o;
1572 					nalloc = n;
1573 				}
1574 				if (line_offsets) {
1575 					off = total_len + i - hdrlen + 1;
1576 					(*line_offsets)[*nlines - 1] = off;
1577 				}
1578 				i++;
1579 			}
1580 		}
1581 		/* Skip blob object header first time around. */
1582 		n = fwrite(buf + hdrlen, 1, len - hdrlen, outfile);
1583 		if (n != len - hdrlen)
1584 			return got_ferror(outfile, GOT_ERR_IO);
1585 		total_len += len - hdrlen;
1586 		hdrlen = 0;
1587 	} while (len != 0);
1588 
1589 	if (fflush(outfile) != 0)
1590 		return got_error_from_errno("fflush");
1591 	rewind(outfile);
1592 
1593 	if (filesize)
1594 		*filesize = total_len;
1595 
1596 	return NULL;
1597 }
1598 
1599 static const struct got_error *
1600 request_packed_tag(struct got_tag_object **tag, struct got_pack *pack,
1601     int pack_idx, struct got_object_id *id)
1602 {
1603 	const struct got_error *err = NULL;
1604 
1605 	err = got_privsep_send_tag_req(pack->privsep_child->ibuf, -1, id,
1606 	    pack_idx);
1607 	if (err)
1608 		return err;
1609 
1610 	return got_privsep_recv_tag(tag, pack->privsep_child->ibuf);
1611 }
1612 
1613 static const struct got_error *
1614 read_packed_tag_privsep(struct got_tag_object **tag,
1615     struct got_pack *pack, struct got_packidx *packidx, int idx,
1616     struct got_object_id *id)
1617 {
1618 	const struct got_error *err = NULL;
1619 
1620 	if (pack->privsep_child)
1621 		return request_packed_tag(tag, pack, idx, id);
1622 
1623 	err = got_pack_start_privsep_child(pack, packidx);
1624 	if (err)
1625 		return err;
1626 
1627 	return request_packed_tag(tag, pack, idx, id);
1628 }
1629 
1630 static const struct got_error *
1631 request_tag(struct got_tag_object **tag, struct got_repository *repo,
1632     int fd, struct got_object_id *id)
1633 {
1634 	const struct got_error *err = NULL;
1635 	struct imsgbuf *ibuf;
1636 
1637 	ibuf = repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_TAG].ibuf;
1638 
1639 	err = got_privsep_send_tag_req(ibuf, fd, id, -1);
1640 	if (err)
1641 		return err;
1642 
1643 	return got_privsep_recv_tag(tag, ibuf);
1644 }
1645 
1646 static const struct got_error *
1647 read_tag_privsep(struct got_tag_object **tag, int obj_fd,
1648     struct got_object_id *id, struct got_repository *repo)
1649 {
1650 	const struct got_error *err;
1651 	int imsg_fds[2];
1652 	pid_t pid;
1653 	struct imsgbuf *ibuf;
1654 
1655 	if (repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_TAG].imsg_fd != -1)
1656 		return request_tag(tag, repo, obj_fd, id);
1657 
1658 	ibuf = calloc(1, sizeof(*ibuf));
1659 	if (ibuf == NULL)
1660 		return got_error_from_errno("calloc");
1661 
1662 	if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, imsg_fds) == -1) {
1663 		err = got_error_from_errno("socketpair");
1664 		free(ibuf);
1665 		return err;
1666 	}
1667 
1668 	pid = fork();
1669 	if (pid == -1) {
1670 		err = got_error_from_errno("fork");
1671 		free(ibuf);
1672 		return err;
1673 	}
1674 	else if (pid == 0) {
1675 		got_privsep_exec_child(imsg_fds, GOT_PATH_PROG_READ_TAG,
1676 		    repo->path);
1677 		/* not reached */
1678 	}
1679 
1680 	if (close(imsg_fds[1]) == -1) {
1681 		err = got_error_from_errno("close");
1682 		free(ibuf);
1683 		return err;
1684 	}
1685 	repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_TAG].imsg_fd =
1686 	    imsg_fds[0];
1687 	repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_TAG].pid = pid;
1688 	imsg_init(ibuf, imsg_fds[0]);
1689 	repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_TAG].ibuf = ibuf;
1690 
1691 	return request_tag(tag, repo, obj_fd, id);
1692 }
1693 
1694 static const struct got_error *
1695 open_tag(struct got_tag_object **tag, struct got_repository *repo,
1696     struct got_object_id *id, int check_cache)
1697 {
1698 	const struct got_error *err = NULL;
1699 	struct got_packidx *packidx = NULL;
1700 	int idx;
1701 	char *path_packfile = NULL;
1702 	struct got_object *obj = NULL;
1703 	int obj_type = GOT_OBJ_TYPE_ANY;
1704 
1705 	if (check_cache) {
1706 		*tag = got_repo_get_cached_tag(repo, id);
1707 		if (*tag != NULL) {
1708 			(*tag)->refcnt++;
1709 			return NULL;
1710 		}
1711 	} else
1712 		*tag = NULL;
1713 
1714 	err = got_repo_search_packidx(&packidx, &idx, repo, id);
1715 	if (err == NULL) {
1716 		struct got_pack *pack = NULL;
1717 
1718 		err = got_packidx_get_packfile_path(&path_packfile,
1719 		    packidx->path_packidx);
1720 		if (err)
1721 			return err;
1722 
1723 		pack = got_repo_get_cached_pack(repo, path_packfile);
1724 		if (pack == NULL) {
1725 			err = got_repo_cache_pack(&pack, repo, path_packfile,
1726 			    packidx);
1727 			if (err)
1728 				goto done;
1729 		}
1730 
1731 		/* Beware of "lightweight" tags: Check object type first. */
1732 		err = read_packed_object_privsep(&obj, repo, pack, packidx,
1733 		    idx, id);
1734 		if (err)
1735 			goto done;
1736 		obj_type = obj->type;
1737 		got_object_close(obj);
1738 		if (obj_type != GOT_OBJ_TYPE_TAG) {
1739 			err = got_error(GOT_ERR_OBJ_TYPE);
1740 			goto done;
1741 		}
1742 		err = read_packed_tag_privsep(tag, pack, packidx, idx, id);
1743 	} else if (err->code == GOT_ERR_NO_OBJ) {
1744 		int fd;
1745 
1746 		err = got_object_open_loose_fd(&fd, id, repo);
1747 		if (err)
1748 			return err;
1749 		err = got_object_read_header_privsep(&obj, id, repo, fd);
1750 		if (err)
1751 			return err;
1752 		obj_type = obj->type;
1753 		got_object_close(obj);
1754 		if (obj_type != GOT_OBJ_TYPE_TAG)
1755 			return got_error(GOT_ERR_OBJ_TYPE);
1756 
1757 		err = got_object_open_loose_fd(&fd, id, repo);
1758 		if (err)
1759 			return err;
1760 		err = read_tag_privsep(tag, fd, id, repo);
1761 	}
1762 
1763 	if (err == NULL) {
1764 		(*tag)->refcnt++;
1765 		err = got_repo_cache_tag(repo, id, *tag);
1766 	}
1767 done:
1768 	free(path_packfile);
1769 	return err;
1770 }
1771 
1772 const struct got_error *
1773 got_object_open_as_tag(struct got_tag_object **tag,
1774     struct got_repository *repo, struct got_object_id *id)
1775 {
1776 	*tag = got_repo_get_cached_tag(repo, id);
1777 	if (*tag != NULL) {
1778 		(*tag)->refcnt++;
1779 		return NULL;
1780 	}
1781 
1782 	return open_tag(tag, repo, id, 0);
1783 }
1784 
1785 const struct got_error *
1786 got_object_tag_open(struct got_tag_object **tag,
1787     struct got_repository *repo, struct got_object *obj)
1788 {
1789 	return open_tag(tag, repo, got_object_get_id(obj), 1);
1790 }
1791 
1792 const char *
1793 got_object_tag_get_name(struct got_tag_object *tag)
1794 {
1795 	return tag->tag;
1796 }
1797 
1798 int
1799 got_object_tag_get_object_type(struct got_tag_object *tag)
1800 {
1801 	return tag->obj_type;
1802 }
1803 
1804 struct got_object_id *
1805 got_object_tag_get_object_id(struct got_tag_object *tag)
1806 {
1807 	return &tag->id;
1808 }
1809 
1810 time_t
1811 got_object_tag_get_tagger_time(struct got_tag_object *tag)
1812 {
1813 	return tag->tagger_time;
1814 }
1815 
1816 time_t
1817 got_object_tag_get_tagger_gmtoff(struct got_tag_object *tag)
1818 {
1819 	return tag->tagger_gmtoff;
1820 }
1821 
1822 const char *
1823 got_object_tag_get_tagger(struct got_tag_object *tag)
1824 {
1825 	return tag->tagger;
1826 }
1827 
1828 const char *
1829 got_object_tag_get_message(struct got_tag_object *tag)
1830 {
1831 	return tag->tagmsg;
1832 }
1833 
1834 static struct got_tree_entry *
1835 find_entry_by_name(struct got_tree_object *tree, const char *name, size_t len)
1836 {
1837 	int i;
1838 
1839 	/* Note that tree entries are sorted in strncmp() order. */
1840 	for (i = 0; i < tree->nentries; i++) {
1841 		struct got_tree_entry *te = &tree->entries[i];
1842 		int cmp = strncmp(te->name, name, len);
1843 		if (cmp < 0)
1844 			continue;
1845 		if (cmp > 0)
1846 			break;
1847 		if (te->name[len] == '\0')
1848 			return te;
1849 	}
1850 	return NULL;
1851 }
1852 
1853 struct got_tree_entry *
1854 got_object_tree_find_entry(struct got_tree_object *tree, const char *name)
1855 {
1856 	return find_entry_by_name(tree, name, strlen(name));
1857 }
1858 
1859 const struct got_error *
1860 got_object_tree_find_path(struct got_object_id **id, mode_t *mode,
1861     struct got_repository *repo, struct got_tree_object *tree,
1862     const char *path)
1863 {
1864 	const struct got_error *err = NULL;
1865 	struct got_tree_object *subtree = NULL;
1866 	struct got_tree_entry *te = NULL;
1867 	const char *seg, *s;
1868 	size_t seglen;
1869 
1870 	*id = NULL;
1871 
1872 	s = path;
1873 	while (s[0] == '/')
1874 		s++;
1875 	seg = s;
1876 	seglen = 0;
1877 	subtree = tree;
1878 	while (*s) {
1879 		struct got_tree_object *next_tree;
1880 
1881 		if (*s != '/') {
1882 			s++;
1883 			seglen++;
1884 			if (*s)
1885 				continue;
1886 		}
1887 
1888 		te = find_entry_by_name(subtree, seg, seglen);
1889 		if (te == NULL) {
1890 			err = got_error_path(path, GOT_ERR_NO_TREE_ENTRY);
1891 			goto done;
1892 		}
1893 
1894 		if (*s == '\0')
1895 			break;
1896 
1897 		seg = s + 1;
1898 		seglen = 0;
1899 		s++;
1900 		if (*s) {
1901 			err = got_object_open_as_tree(&next_tree, repo,
1902 			    &te->id);
1903 			te = NULL;
1904 			if (err)
1905 				goto done;
1906 			if (subtree != tree)
1907 				got_object_tree_close(subtree);
1908 			subtree = next_tree;
1909 		}
1910 	}
1911 
1912 	if (te) {
1913 		*id = got_object_id_dup(&te->id);
1914 		if (*id == NULL)
1915 			return got_error_from_errno("got_object_id_dup");
1916 		if (mode)
1917 			*mode = te->mode;
1918 	} else
1919 		err = got_error_path(path, GOT_ERR_NO_TREE_ENTRY);
1920 done:
1921 	if (subtree && subtree != tree)
1922 		got_object_tree_close(subtree);
1923 	return err;
1924 }
1925 const struct got_error *
1926 got_object_id_by_path(struct got_object_id **id, struct got_repository *repo,
1927     struct got_commit_object *commit, const char *path)
1928 {
1929 	const struct got_error *err = NULL;
1930 	struct got_tree_object *tree = NULL;
1931 
1932 	*id = NULL;
1933 
1934 	/* Handle opening of root of commit's tree. */
1935 	if (got_path_is_root_dir(path)) {
1936 		*id = got_object_id_dup(commit->tree_id);
1937 		if (*id == NULL)
1938 			err = got_error_from_errno("got_object_id_dup");
1939 	} else {
1940 		err = got_object_open_as_tree(&tree, repo, commit->tree_id);
1941 		if (err)
1942 			goto done;
1943 		err = got_object_tree_find_path(id, NULL, repo, tree, path);
1944 	}
1945 done:
1946 	if (tree)
1947 		got_object_tree_close(tree);
1948 	return err;
1949 }
1950 
1951 /*
1952  * Normalize file mode bits to avoid false positive tree entry differences
1953  * in case tree entries have unexpected mode bits set.
1954  */
1955 static mode_t
1956 normalize_mode_for_comparison(mode_t mode)
1957 {
1958 	/*
1959 	 * For directories, the only relevant bit is the IFDIR bit.
1960 	 * This allows us to detect paths changing from a directory
1961 	 * to a file and vice versa.
1962 	 */
1963 	if (S_ISDIR(mode))
1964 		return mode & S_IFDIR;
1965 
1966 	/*
1967 	 * For symlinks, the only relevant bit is the IFLNK bit.
1968 	 * This allows us to detect paths changing from a symlinks
1969 	 * to a file or directory and vice versa.
1970 	 */
1971 	if (S_ISLNK(mode))
1972 		return mode & S_IFLNK;
1973 
1974 	/* For files, the only change we care about is the executable bit. */
1975 	return mode & S_IXUSR;
1976 }
1977 
1978 const struct got_error *
1979 got_object_tree_path_changed(int *changed,
1980     struct got_tree_object *tree01, struct got_tree_object *tree02,
1981     const char *path, struct got_repository *repo)
1982 {
1983 	const struct got_error *err = NULL;
1984 	struct got_tree_object *tree1 = NULL, *tree2 = NULL;
1985 	struct got_tree_entry *te1 = NULL, *te2 = NULL;
1986 	const char *seg, *s;
1987 	size_t seglen;
1988 
1989 	*changed = 0;
1990 
1991 	/* We not do support comparing the root path. */
1992 	if (got_path_is_root_dir(path))
1993 		return got_error_path(path, GOT_ERR_BAD_PATH);
1994 
1995 	tree1 = tree01;
1996 	tree2 = tree02;
1997 	s = path;
1998 	while (*s == '/')
1999 		s++;
2000 	seg = s;
2001 	seglen = 0;
2002 	while (*s) {
2003 		struct got_tree_object *next_tree1, *next_tree2;
2004 		mode_t mode1, mode2;
2005 
2006 		if (*s != '/') {
2007 			s++;
2008 			seglen++;
2009 			if (*s)
2010 				continue;
2011 		}
2012 
2013 		te1 = find_entry_by_name(tree1, seg, seglen);
2014 		if (te1 == NULL) {
2015 			err = got_error(GOT_ERR_NO_OBJ);
2016 			goto done;
2017 		}
2018 
2019 		if (tree2)
2020 			te2 = find_entry_by_name(tree2, seg, seglen);
2021 
2022 		if (te2) {
2023 			mode1 = normalize_mode_for_comparison(te1->mode);
2024 			mode2 = normalize_mode_for_comparison(te2->mode);
2025 			if (mode1 != mode2) {
2026 				*changed = 1;
2027 				goto done;
2028 			}
2029 
2030 			if (got_object_id_cmp(&te1->id, &te2->id) == 0) {
2031 				*changed = 0;
2032 				goto done;
2033 			}
2034 		}
2035 
2036 		if (*s == '\0') { /* final path element */
2037 			*changed = 1;
2038 			goto done;
2039 		}
2040 
2041 		seg = s + 1;
2042 		s++;
2043 		seglen = 0;
2044 		if (*s) {
2045 			err = got_object_open_as_tree(&next_tree1, repo,
2046 			    &te1->id);
2047 			te1 = NULL;
2048 			if (err)
2049 				goto done;
2050 			if (tree1 != tree01)
2051 				got_object_tree_close(tree1);
2052 			tree1 = next_tree1;
2053 
2054 			if (te2) {
2055 				err = got_object_open_as_tree(&next_tree2, repo,
2056 				    &te2->id);
2057 				te2 = NULL;
2058 				if (err)
2059 					goto done;
2060 				if (tree2 != tree02)
2061 					got_object_tree_close(tree2);
2062 				tree2 = next_tree2;
2063 			} else if (tree2) {
2064 				if (tree2 != tree02)
2065 					got_object_tree_close(tree2);
2066 				tree2 = NULL;
2067 			}
2068 		}
2069 	}
2070 done:
2071 	if (tree1 && tree1 != tree01)
2072 		got_object_tree_close(tree1);
2073 	if (tree2 && tree2 != tree02)
2074 		got_object_tree_close(tree2);
2075 	return err;
2076 }
2077 
2078 const struct got_error *
2079 got_object_tree_entry_dup(struct got_tree_entry **new_te,
2080     struct got_tree_entry *te)
2081 {
2082 	const struct got_error *err = NULL;
2083 
2084 	*new_te = calloc(1, sizeof(**new_te));
2085 	if (*new_te == NULL)
2086 		return got_error_from_errno("calloc");
2087 
2088 	(*new_te)->mode = te->mode;
2089 	memcpy((*new_te)->name, te->name, sizeof((*new_te)->name));
2090 	memcpy(&(*new_te)->id, &te->id, sizeof((*new_te)->id));
2091 	return err;
2092 }
2093 
2094 int
2095 got_object_tree_entry_is_submodule(struct got_tree_entry *te)
2096 {
2097 	return (te->mode & S_IFMT) == (S_IFDIR | S_IFLNK);
2098 }
2099 
2100 int
2101 got_object_tree_entry_is_symlink(struct got_tree_entry *te)
2102 {
2103 	/* S_IFDIR check avoids confusing symlinks with submodules. */
2104 	return ((te->mode & (S_IFDIR | S_IFLNK)) == S_IFLNK);
2105 }
2106 
2107 static const struct got_error *
2108 resolve_symlink(char **link_target, const char *path,
2109     struct got_commit_object *commit, struct got_repository *repo)
2110 {
2111 	const struct got_error *err = NULL;
2112 	char buf[PATH_MAX];
2113 	char *name, *parent_path = NULL;
2114 	struct got_object_id *tree_obj_id = NULL;
2115 	struct got_tree_object *tree = NULL;
2116 	struct got_tree_entry *te = NULL;
2117 
2118 	*link_target = NULL;
2119 
2120 	if (strlcpy(buf, path, sizeof(buf)) >= sizeof(buf))
2121 		return got_error(GOT_ERR_NO_SPACE);
2122 
2123 	name = basename(buf);
2124 	if (name == NULL)
2125 		return got_error_from_errno2("basename", path);
2126 
2127 	err = got_path_dirname(&parent_path, path);
2128 	if (err)
2129 		return err;
2130 
2131 	err = got_object_id_by_path(&tree_obj_id, repo, commit,
2132 	    parent_path);
2133 	if (err) {
2134 		if (err->code == GOT_ERR_NO_TREE_ENTRY) {
2135 			/* Display the complete path in error message. */
2136 			err = got_error_path(path, err->code);
2137 		}
2138 		goto done;
2139 	}
2140 
2141 	err = got_object_open_as_tree(&tree, repo, tree_obj_id);
2142 	if (err)
2143 		goto done;
2144 
2145 	te = got_object_tree_find_entry(tree, name);
2146 	if (te == NULL) {
2147 		err = got_error_path(path, GOT_ERR_NO_TREE_ENTRY);
2148 		goto done;
2149 	}
2150 
2151 	if (got_object_tree_entry_is_symlink(te)) {
2152 		err = got_tree_entry_get_symlink_target(link_target, te, repo);
2153 		if (err)
2154 			goto done;
2155 		if (!got_path_is_absolute(*link_target)) {
2156 			char *abspath;
2157 			if (asprintf(&abspath, "%s/%s", parent_path,
2158 			    *link_target) == -1) {
2159 				err = got_error_from_errno("asprintf");
2160 				goto done;
2161 			}
2162 			free(*link_target);
2163 			*link_target = malloc(PATH_MAX);
2164 			if (*link_target == NULL) {
2165 				err = got_error_from_errno("malloc");
2166 				goto done;
2167 			}
2168 			err = got_canonpath(abspath, *link_target, PATH_MAX);
2169 			free(abspath);
2170 			if (err)
2171 				goto done;
2172 		}
2173 	}
2174 done:
2175 	free(tree_obj_id);
2176 	if (tree)
2177 		got_object_tree_close(tree);
2178 	if (err) {
2179 		free(*link_target);
2180 		*link_target = NULL;
2181 	}
2182 	return err;
2183 }
2184 
2185 const struct got_error *
2186 got_object_resolve_symlinks(char **link_target, const char *path,
2187     struct got_commit_object *commit, struct got_repository *repo)
2188 {
2189 	const struct got_error *err = NULL;
2190 	char *next_target = NULL;
2191 	int max_recursion = 40; /* matches Git */
2192 
2193 	*link_target = NULL;
2194 
2195 	do {
2196 		err = resolve_symlink(&next_target,
2197 		    *link_target ? *link_target : path, commit, repo);
2198 		if (err)
2199 			break;
2200 		if (next_target) {
2201 			free(*link_target);
2202 			if (--max_recursion == 0) {
2203 				err = got_error_path(path, GOT_ERR_RECURSION);
2204 				*link_target = NULL;
2205 				break;
2206 			}
2207 			*link_target = next_target;
2208 		}
2209 	} while (next_target);
2210 
2211 	return err;
2212 }
2213 
2214 const struct got_error *
2215 got_traverse_packed_commits(struct got_object_id_queue *traversed_commits,
2216     struct got_object_id *commit_id, const char *path,
2217     struct got_repository *repo)
2218 {
2219 	const struct got_error *err = NULL;
2220 	struct got_pack *pack = NULL;
2221 	struct got_packidx *packidx = NULL;
2222 	char *path_packfile = NULL;
2223 	struct got_commit_object *changed_commit = NULL;
2224 	struct got_object_id *changed_commit_id = NULL;
2225 	int idx;
2226 
2227 	err = got_repo_search_packidx(&packidx, &idx, repo, commit_id);
2228 	if (err) {
2229 		if (err->code != GOT_ERR_NO_OBJ)
2230 			return err;
2231 		return NULL;
2232 	}
2233 
2234 	err = got_packidx_get_packfile_path(&path_packfile,
2235 	    packidx->path_packidx);
2236 	if (err)
2237 		return err;
2238 
2239 	pack = got_repo_get_cached_pack(repo, path_packfile);
2240 	if (pack == NULL) {
2241 		err = got_repo_cache_pack(&pack, repo, path_packfile, packidx);
2242 		if (err)
2243 			goto done;
2244 	}
2245 
2246 	if (pack->privsep_child == NULL) {
2247 		err = got_pack_start_privsep_child(pack, packidx);
2248 		if (err)
2249 			goto done;
2250 	}
2251 
2252 	err = got_privsep_send_commit_traversal_request(
2253 	    pack->privsep_child->ibuf, commit_id, idx, path);
2254 	if (err)
2255 		goto done;
2256 
2257 	err = got_privsep_recv_traversed_commits(&changed_commit,
2258 	    &changed_commit_id, traversed_commits, pack->privsep_child->ibuf);
2259 	if (err)
2260 		goto done;
2261 
2262 	if (changed_commit) {
2263 		/*
2264 		 * Cache the commit in which the path was changed.
2265 		 * This commit might be opened again soon.
2266 		 */
2267 		changed_commit->refcnt++;
2268 		err = got_repo_cache_commit(repo, changed_commit_id,
2269 		    changed_commit);
2270 		got_object_commit_close(changed_commit);
2271 	}
2272 done:
2273 	free(path_packfile);
2274 	free(changed_commit_id);
2275 	return err;
2276 }
2277 
2278 const struct got_error *
2279 got_object_enumerate(int *found_all_objects,
2280     got_object_enumerate_commit_cb cb_commit,
2281     got_object_enumerate_tree_cb cb_tree, void *cb_arg,
2282     struct got_object_id **ours, int nours,
2283     struct got_object_id **theirs, int ntheirs,
2284     struct got_packidx *packidx, struct got_repository *repo)
2285 {
2286 	const struct got_error *err = NULL;
2287 	struct got_pack *pack;
2288 	char *path_packfile = NULL;
2289 
2290 	err = got_packidx_get_packfile_path(&path_packfile,
2291 	    packidx->path_packidx);
2292 	if (err)
2293 		return err;
2294 
2295 	pack = got_repo_get_cached_pack(repo, path_packfile);
2296 	if (pack == NULL) {
2297 		err = got_repo_cache_pack(&pack, repo, path_packfile, packidx);
2298 		if (err)
2299 			goto done;
2300 	}
2301 
2302 	if (pack->privsep_child == NULL) {
2303 		err = got_pack_start_privsep_child(pack, packidx);
2304 		if (err)
2305 			goto done;
2306 	}
2307 
2308 	err = got_privsep_send_object_enumeration_request(
2309 	    pack->privsep_child->ibuf);
2310 	if (err)
2311 		goto done;
2312 
2313 	err = got_privsep_send_object_idlist(pack->privsep_child->ibuf,
2314 	    ours, nours);
2315 	if (err)
2316 		goto done;
2317 	err = got_privsep_send_object_idlist_done(pack->privsep_child->ibuf);
2318 	if (err)
2319 		goto done;
2320 
2321 	err = got_privsep_send_object_idlist(pack->privsep_child->ibuf,
2322 	    theirs, ntheirs);
2323 	if (err)
2324 		goto done;
2325 	err = got_privsep_send_object_idlist_done(pack->privsep_child->ibuf);
2326 	if (err)
2327 		goto done;
2328 
2329 	err = got_privsep_recv_enumerated_objects(found_all_objects,
2330 	    pack->privsep_child->ibuf, cb_commit, cb_tree, cb_arg, repo);
2331 done:
2332 	free(path_packfile);
2333 	return err;
2334 }