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/resource.h>
23 #include <sys/mman.h>
24 
25 #include <errno.h>
26 #include <fcntl.h>
27 #include <stdio.h>
28 #include <stdlib.h>
29 #include <string.h>
30 #include <stdint.h>
31 #include <unistd.h>
32 #include <zlib.h>
33 #include <ctype.h>
34 #include <libgen.h>
35 #include <limits.h>
36 #include <time.h>
37 
38 #include "got_compat.h"
39 
40 #include "got_error.h"
41 #include "got_object.h"
42 #include "got_repository.h"
43 #include "got_opentemp.h"
44 #include "got_path.h"
45 
46 #include "got_lib_sha1.h"
47 #include "got_lib_delta.h"
48 #include "got_lib_inflate.h"
49 #include "got_lib_object.h"
50 #include "got_lib_privsep.h"
51 #include "got_lib_object_idcache.h"
52 #include "got_lib_object_cache.h"
53 #include "got_lib_object_parse.h"
54 #include "got_lib_pack.h"
55 #include "got_lib_repository.h"
56 
57 #ifndef MIN
58 #define	MIN(_a,_b) ((_a) < (_b) ? (_a) : (_b))
59 #endif
60 
61 #ifndef nitems
62 #define nitems(_a)	(sizeof((_a)) / sizeof((_a)[0]))
63 #endif
64 
65 struct got_object_id *
66 got_object_get_id(struct got_object *obj)
67 {
68 	return &obj->id;
69 }
70 
71 const struct got_error *
72 got_object_get_id_str(char **outbuf, struct got_object *obj)
73 {
74 	return got_object_id_str(outbuf, &obj->id);
75 }
76 
77 const struct got_error *
78 got_object_get_type(int *type, struct got_repository *repo,
79     struct got_object_id *id)
80 {
81 	const struct got_error *err = NULL;
82 	struct got_object *obj;
83 
84 	err = got_object_open(&obj, repo, id);
85 	if (err)
86 		return err;
87 
88 	switch (obj->type) {
89 	case GOT_OBJ_TYPE_COMMIT:
90 	case GOT_OBJ_TYPE_TREE:
91 	case GOT_OBJ_TYPE_BLOB:
92 	case GOT_OBJ_TYPE_TAG:
93 		*type = obj->type;
94 		break;
95 	default:
96 		err = got_error(GOT_ERR_OBJ_TYPE);
97 		break;
98 	}
99 
100 	got_object_close(obj);
101 	return err;
102 }
103 
104 const struct got_error *
105 got_object_get_path(char **path, struct got_object_id *id,
106     struct got_repository *repo)
107 {
108 	const struct got_error *err = NULL;
109 	char *hex = NULL;
110 	char *path_objects;
111 
112 	*path = NULL;
113 
114 	path_objects = got_repo_get_path_objects(repo);
115 	if (path_objects == NULL)
116 		return got_error_from_errno("got_repo_get_path_objects");
117 
118 	err = got_object_id_str(&hex, id);
119 	if (err)
120 		goto done;
121 
122 	if (asprintf(path, "%s/%.2x/%s", path_objects,
123 	    id->sha1[0], hex + 2) == -1)
124 		err = got_error_from_errno("asprintf");
125 
126 done:
127 	free(hex);
128 	free(path_objects);
129 	return err;
130 }
131 
132 const struct got_error *
133 got_object_open_loose_fd(int *fd, struct got_object_id *id,
134     struct got_repository *repo)
135 {
136 	const struct got_error *err = NULL;
137 	char *path;
138 
139 	err = got_object_get_path(&path, id, repo);
140 	if (err)
141 		return err;
142 	*fd = open(path, O_RDONLY | O_NOFOLLOW | O_CLOEXEC);
143 	if (*fd == -1) {
144 		err = got_error_from_errno2("open", path);
145 		goto done;
146 	}
147 done:
148 	free(path);
149 	return err;
150 }
151 
152 static const struct got_error *
153 request_packed_object(struct got_object **obj, struct got_pack *pack, int idx,
154     struct got_object_id *id)
155 {
156 	const struct got_error *err = NULL;
157 	struct imsgbuf *ibuf = pack->privsep_child->ibuf;
158 
159 	err = got_privsep_send_packed_obj_req(ibuf, idx, id);
160 	if (err)
161 		return err;
162 
163 	err = got_privsep_recv_obj(obj, ibuf);
164 	if (err)
165 		return err;
166 
167 	memcpy(&(*obj)->id, id, sizeof((*obj)->id));
168 
169 	return NULL;
170 }
171 
172 /* Create temporary files used during delta application. */
173 static const struct got_error *
174 pack_child_send_tempfiles(struct imsgbuf *ibuf, struct got_pack *pack)
175 {
176 	const struct got_error *err;
177 	int basefd = -1, accumfd = -1;
178 
179 	/* 
180 	 * For performance reasons, the child will keep reusing the
181 	 * same temporary files during every object request.
182 	 * Opening and closing new files for every object request is
183 	 * too expensive during operations such as 'gotadmin pack'.
184 	 */
185 	if (pack->child_has_tempfiles)
186 		return NULL;
187 
188 	basefd = dup(pack->basefd);
189 	if (basefd == -1)
190 		return got_error_from_errno("dup");
191 
192 	accumfd = dup(pack->accumfd);
193 	if (accumfd == -1) {
194 		err = got_error_from_errno("dup");
195 		goto done;
196 	}
197 
198 	err = got_privsep_send_tmpfd(ibuf, basefd);
199 	if (err)
200 		goto done;
201 
202 	err = got_privsep_send_tmpfd(ibuf, accumfd);
203 done:
204 	if (err) {
205 		if (basefd != -1)
206 			close(basefd);
207 		if (accumfd != -1)
208 			close(accumfd);
209 	} else
210 		pack->child_has_tempfiles = 1;
211 	return NULL;
212 }
213 
214 static const struct got_error *
215 request_packed_object_raw(uint8_t **outbuf, off_t *size, size_t *hdrlen,
216     int outfd, struct got_pack *pack, int idx, struct got_object_id *id)
217 {
218 	const struct got_error *err = NULL;
219 	struct imsgbuf *ibuf = pack->privsep_child->ibuf;
220 	int outfd_child;
221 
222 	 err = pack_child_send_tempfiles(ibuf, pack);
223 	 if (err)
224 		return err;
225 
226 	outfd_child = dup(outfd);
227 	if (outfd_child == -1)
228 		return got_error_from_errno("dup");
229 
230 	err = got_privsep_send_packed_raw_obj_req(ibuf, idx, id);
231 	if (err) {
232 		close(outfd_child);
233 		return err;
234 	}
235 
236 	err = got_privsep_send_raw_obj_outfd(ibuf, outfd_child);
237 	if (err)
238 		return err;
239 
240 	err = got_privsep_recv_raw_obj(outbuf, size, hdrlen, ibuf);
241 	if (err)
242 		return err;
243 
244 	return NULL;
245 }
246 
247 static void
248 set_max_datasize(void)
249 {
250 	struct rlimit rl;
251 
252 	if (getrlimit(RLIMIT_DATA, &rl) != 0)
253 		return;
254 
255 	rl.rlim_cur = rl.rlim_max;
256 	setrlimit(RLIMIT_DATA, &rl);
257 }
258 
259 static const struct got_error *
260 start_pack_privsep_child(struct got_pack *pack, struct got_packidx *packidx)
261 {
262 	const struct got_error *err = NULL;
263 	int imsg_fds[2];
264 	pid_t pid;
265 	struct imsgbuf *ibuf;
266 
267 	ibuf = calloc(1, sizeof(*ibuf));
268 	if (ibuf == NULL)
269 		return got_error_from_errno("calloc");
270 
271 	pack->privsep_child = calloc(1, sizeof(*pack->privsep_child));
272 	if (pack->privsep_child == NULL) {
273 		err = got_error_from_errno("calloc");
274 		free(ibuf);
275 		return err;
276 	}
277 	pack->child_has_tempfiles = 0;
278 	pack->child_has_delta_outfd = 0;
279 
280 	if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, imsg_fds) == -1) {
281 		err = got_error_from_errno("socketpair");
282 		goto done;
283 	}
284 
285 	pid = fork();
286 	if (pid == -1) {
287 		err = got_error_from_errno("fork");
288 		goto done;
289 	} else if (pid == 0) {
290 		set_max_datasize();
291 		got_privsep_exec_child(imsg_fds, GOT_PATH_PROG_READ_PACK,
292 		    pack->path_packfile);
293 		/* not reached */
294 	}
295 
296 	if (close(imsg_fds[1]) == -1)
297 		return got_error_from_errno("close");
298 	pack->privsep_child->imsg_fd = imsg_fds[0];
299 	pack->privsep_child->pid = pid;
300 	imsg_init(ibuf, imsg_fds[0]);
301 	pack->privsep_child->ibuf = ibuf;
302 
303 	err = got_privsep_init_pack_child(ibuf, pack, packidx);
304 	if (err) {
305 		const struct got_error *child_err;
306 		err = got_privsep_send_stop(pack->privsep_child->imsg_fd);
307 		child_err = got_privsep_wait_for_child(
308 		    pack->privsep_child->pid);
309 		if (child_err && err == NULL)
310 			err = child_err;
311 	}
312 done:
313 	if (err) {
314 		free(ibuf);
315 		free(pack->privsep_child);
316 		pack->privsep_child = NULL;
317 	}
318 	return err;
319 }
320 
321 static const struct got_error *
322 read_packed_object_privsep(struct got_object **obj,
323     struct got_repository *repo, struct got_pack *pack,
324     struct got_packidx *packidx, int idx, struct got_object_id *id)
325 {
326 	const struct got_error *err = NULL;
327 
328 	if (pack->privsep_child == NULL) {
329 		err = start_pack_privsep_child(pack, packidx);
330 		if (err)
331 			return err;
332 	}
333 
334 	return request_packed_object(obj, pack, idx, id);
335 }
336 
337 static const struct got_error *
338 read_packed_object_raw_privsep(uint8_t **outbuf, off_t *size, size_t *hdrlen,
339     int outfd, struct got_pack *pack, struct got_packidx *packidx, int idx,
340     struct got_object_id *id)
341 {
342 	const struct got_error *err = NULL;
343 
344 	if (pack->privsep_child == NULL) {
345 		err = start_pack_privsep_child(pack, packidx);
346 		if (err)
347 			return err;
348 	}
349 
350 	return request_packed_object_raw(outbuf, size, hdrlen, outfd, pack,
351 	    idx, id);
352 }
353 
354 const struct got_error *
355 got_object_open_packed(struct got_object **obj, struct got_object_id *id,
356     struct got_repository *repo)
357 {
358 	const struct got_error *err = NULL;
359 	struct got_pack *pack = NULL;
360 	struct got_packidx *packidx = NULL;
361 	int idx;
362 	char *path_packfile;
363 
364 	err = got_repo_search_packidx(&packidx, &idx, repo, id);
365 	if (err)
366 		return err;
367 
368 	err = got_packidx_get_packfile_path(&path_packfile,
369 	    packidx->path_packidx);
370 	if (err)
371 		return err;
372 
373 	pack = got_repo_get_cached_pack(repo, path_packfile);
374 	if (pack == NULL) {
375 		err = got_repo_cache_pack(&pack, repo, path_packfile, packidx);
376 		if (err)
377 			goto done;
378 	}
379 
380 	err = read_packed_object_privsep(obj, repo, pack, packidx, idx, id);
381 	if (err)
382 		goto done;
383 done:
384 	free(path_packfile);
385 	return err;
386 }
387 
388 const struct got_error *
389 got_object_open_from_packfile(struct got_object **obj, struct got_object_id *id,
390     struct got_pack *pack, struct got_packidx *packidx, int obj_idx,
391     struct got_repository *repo)
392 {
393 	return read_packed_object_privsep(obj, repo, pack, packidx,
394 	    obj_idx, id);
395 }
396 
397 const struct got_error *
398 got_object_read_raw_delta(uint64_t *base_size, uint64_t *result_size,
399     off_t *delta_size, off_t *delta_compressed_size, off_t *delta_offset,
400     off_t *delta_out_offset, struct got_object_id **base_id, int delta_cache_fd,
401     struct got_packidx *packidx, int obj_idx, struct got_object_id *id,
402     struct got_repository *repo)
403 {
404 	const struct got_error *err = NULL;
405 	struct got_pack *pack = NULL;
406 	char *path_packfile;
407 
408 	*base_size = 0;
409 	*result_size = 0;
410 	*delta_size = 0;
411 	*delta_compressed_size = 0;
412 	*delta_offset = 0;
413 	*delta_out_offset = 0;
414 
415 	err = got_packidx_get_packfile_path(&path_packfile,
416 	    packidx->path_packidx);
417 	if (err)
418 		return err;
419 
420 	pack = got_repo_get_cached_pack(repo, path_packfile);
421 	if (pack == NULL) {
422 		err = got_repo_cache_pack(&pack, repo, path_packfile, packidx);
423 		if (err)
424 			return err;
425 	}
426 
427 	if (pack->privsep_child == NULL) {
428 		err = start_pack_privsep_child(pack, packidx);
429 		if (err)
430 			return err;
431 	}
432 
433 	if (!pack->child_has_delta_outfd) {
434 		int outfd_child;
435 		outfd_child = dup(delta_cache_fd);
436 		if (outfd_child == -1)
437 			return got_error_from_errno("dup");
438 		err = got_privsep_send_raw_delta_outfd(
439 		    pack->privsep_child->ibuf, outfd_child);
440 		if (err)
441 			return err;
442 		pack->child_has_delta_outfd = 1;
443 	}
444 
445 	err = got_privsep_send_raw_delta_req(pack->privsep_child->ibuf,
446 	    obj_idx, id);
447 	if (err)
448 		return err;
449 
450 	return got_privsep_recv_raw_delta(base_size, result_size, delta_size,
451 	    delta_compressed_size, delta_offset, delta_out_offset, base_id,
452 	    pack->privsep_child->ibuf);
453 }
454 
455 /*
456  * XXX This function does not really belong in object.c. It is only here
457  * because it needs start_pack_privsep_child(); relevant code should
458  * probably be moved to pack.c/pack_create.c.
459  */
460 const struct got_error *
461 got_object_prepare_delta_reuse(struct got_pack **pack,
462     struct got_packidx *packidx, int delta_outfd, struct got_repository *repo)
463 {
464 	const struct got_error *err = NULL;
465 	char *path_packfile = NULL;
466 
467 	err = got_packidx_get_packfile_path(&path_packfile,
468 	    packidx->path_packidx);
469 	if (err)
470 		return err;
471 
472 	*pack = got_repo_get_cached_pack(repo, path_packfile);
473 	if (*pack == NULL) {
474 		err = got_repo_cache_pack(pack, repo, path_packfile, packidx);
475 		if (err)
476 			goto done;
477 	}
478 	if ((*pack)->privsep_child == NULL) {
479 		err = start_pack_privsep_child(*pack, packidx);
480 		if (err)
481 			goto done;
482 	}
483 
484 	if (!(*pack)->child_has_delta_outfd) {
485 		int outfd_child;
486 		outfd_child = dup(delta_outfd);
487 		if (outfd_child == -1) {
488 			err = got_error_from_errno("dup");
489 			goto done;
490 		}
491 		err = got_privsep_send_raw_delta_outfd(
492 		    (*pack)->privsep_child->ibuf, outfd_child);
493 		if (err)
494 			goto done;
495 		(*pack)->child_has_delta_outfd = 1;
496 	}
497 
498 	err = got_privsep_send_delta_reuse_req((*pack)->privsep_child->ibuf);
499 done:
500 	free(path_packfile);
501 	return err;
502 }
503 
504 static const struct got_error *
505 request_object(struct got_object **obj, struct got_object_id *id,
506     struct got_repository *repo, int fd)
507 {
508 	const struct got_error *err = NULL;
509 	struct imsgbuf *ibuf;
510 
511 	ibuf = repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_OBJECT].ibuf;
512 
513 	err = got_privsep_send_obj_req(ibuf, fd, id);
514 	if (err)
515 		return err;
516 
517 	return got_privsep_recv_obj(obj, ibuf);
518 }
519 
520 static const struct got_error *
521 request_raw_object(uint8_t **outbuf, off_t *size, size_t *hdrlen, int outfd,
522     struct got_object_id *id, struct got_repository *repo, int infd)
523 {
524 	const struct got_error *err = NULL;
525 	struct imsgbuf *ibuf;
526 	int outfd_child;
527 
528 	ibuf = repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_OBJECT].ibuf;
529 
530 	outfd_child = dup(outfd);
531 	if (outfd_child == -1)
532 		return got_error_from_errno("dup");
533 
534 	err = got_privsep_send_raw_obj_req(ibuf, infd, id);
535 	if (err)
536 		return err;
537 
538 	err = got_privsep_send_raw_obj_outfd(ibuf, outfd_child);
539 	if (err)
540 		return err;
541 
542 	return got_privsep_recv_raw_obj(outbuf, size, hdrlen, ibuf);
543 }
544 
545 static const struct got_error *
546 start_read_object_child(struct got_repository *repo)
547 {
548 	const struct got_error *err = NULL;
549 	int imsg_fds[2];
550 	pid_t pid;
551 	struct imsgbuf *ibuf;
552 
553 	ibuf = calloc(1, sizeof(*ibuf));
554 	if (ibuf == NULL)
555 		return got_error_from_errno("calloc");
556 
557 	if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, imsg_fds) == -1) {
558 		err = got_error_from_errno("socketpair");
559 		free(ibuf);
560 		return err;
561 	}
562 
563 	pid = fork();
564 	if (pid == -1) {
565 		err = got_error_from_errno("fork");
566 		free(ibuf);
567 		return err;
568 	}
569 	else if (pid == 0) {
570 		got_privsep_exec_child(imsg_fds, GOT_PATH_PROG_READ_OBJECT,
571 		    repo->path);
572 		/* not reached */
573 	}
574 
575 	if (close(imsg_fds[1]) == -1) {
576 		err = got_error_from_errno("close");
577 		free(ibuf);
578 		return err;
579 	}
580 
581 	repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_OBJECT].imsg_fd =
582 	    imsg_fds[0];
583 	repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_OBJECT].pid = pid;
584 	imsg_init(ibuf, imsg_fds[0]);
585 	repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_OBJECT].ibuf = ibuf;
586 
587 	return NULL;
588 }
589 
590 const struct got_error *
591 got_object_read_header_privsep(struct got_object **obj,
592     struct got_object_id *id, struct got_repository *repo, int obj_fd)
593 {
594 	const struct got_error *err;
595 
596 	if (repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_OBJECT].imsg_fd != -1)
597 		return request_object(obj, id, repo, obj_fd);
598 
599 	err = start_read_object_child(repo);
600 	if (err) {
601 		close(obj_fd);
602 		return err;
603 	}
604 
605 	return request_object(obj, id, repo, obj_fd);
606 }
607 
608 static const struct got_error *
609 read_object_raw_privsep(uint8_t **outbuf, off_t *size, size_t *hdrlen,
610     int outfd, struct got_object_id *id, struct got_repository *repo,
611     int obj_fd)
612 {
613 	const struct got_error *err;
614 
615 	if (repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_OBJECT].imsg_fd != -1)
616 		return request_raw_object(outbuf, size, hdrlen, outfd, id,
617 		    repo, obj_fd);
618 
619 	err = start_read_object_child(repo);
620 	if (err)
621 		return err;
622 
623 	return request_raw_object(outbuf, size, hdrlen, outfd, id, repo,
624 	    obj_fd);
625 }
626 
627 const struct got_error *
628 got_object_open(struct got_object **obj, struct got_repository *repo,
629     struct got_object_id *id)
630 {
631 	const struct got_error *err = NULL;
632 	int fd;
633 
634 	*obj = got_repo_get_cached_object(repo, id);
635 	if (*obj != NULL) {
636 		(*obj)->refcnt++;
637 		return NULL;
638 	}
639 
640 	err = got_object_open_packed(obj, id, repo);
641 	if (err && err->code != GOT_ERR_NO_OBJ)
642 		return err;
643 	if (*obj) {
644 		(*obj)->refcnt++;
645 		return got_repo_cache_object(repo, id, *obj);
646 	}
647 
648 	err = got_object_open_loose_fd(&fd, id, repo);
649 	if (err) {
650 		if (err->code == GOT_ERR_ERRNO && errno == ENOENT)
651 			err = got_error_no_obj(id);
652 		return err;
653 	}
654 
655 	err = got_object_read_header_privsep(obj, id, repo, fd);
656 	if (err)
657 		return err;
658 
659 	memcpy((*obj)->id.sha1, id->sha1, SHA1_DIGEST_LENGTH);
660 
661 	(*obj)->refcnt++;
662 	return got_repo_cache_object(repo, id, *obj);
663 }
664 
665 /* *outfd must be initialized to -1 by caller */
666 const struct got_error *
667 got_object_raw_open(struct got_raw_object **obj, int *outfd,
668     struct got_repository *repo, struct got_object_id *id)
669 {
670 	const struct got_error *err = NULL;
671 	struct got_packidx *packidx = NULL;
672 	int idx;
673 	uint8_t *outbuf = NULL;
674 	off_t size = 0;
675 	size_t hdrlen = 0;
676 	char *path_packfile = NULL;
677 
678 	*obj = got_repo_get_cached_raw_object(repo, id);
679 	if (*obj != NULL) {
680 		(*obj)->refcnt++;
681 		return NULL;
682 	}
683 
684 	if (*outfd == -1) {
685 		*outfd = got_opentempfd();
686 		if (*outfd == -1)
687 			return got_error_from_errno("got_opentempfd");
688 	}
689 
690 	err = got_repo_search_packidx(&packidx, &idx, repo, id);
691 	if (err == NULL) {
692 		struct got_pack *pack = NULL;
693 
694 		err = got_packidx_get_packfile_path(&path_packfile,
695 		    packidx->path_packidx);
696 		if (err)
697 			goto done;
698 
699 		pack = got_repo_get_cached_pack(repo, path_packfile);
700 		if (pack == NULL) {
701 			err = got_repo_cache_pack(&pack, repo, path_packfile,
702 			    packidx);
703 			if (err)
704 				goto done;
705 		}
706 		err = read_packed_object_raw_privsep(&outbuf, &size, &hdrlen,
707 		    *outfd, pack, packidx, idx, id);
708 		if (err)
709 			goto done;
710 	} else if (err->code == GOT_ERR_NO_OBJ) {
711 		int fd;
712 
713 		err = got_object_open_loose_fd(&fd, id, repo);
714 		if (err)
715 			goto done;
716 		err = read_object_raw_privsep(&outbuf, &size, &hdrlen, *outfd,
717 		    id, repo, fd);
718 		if (err)
719 			goto done;
720 	}
721 
722 	*obj = calloc(1, sizeof(**obj));
723 	if (*obj == NULL) {
724 		err = got_error_from_errno("calloc");
725 		goto done;
726 	}
727 	(*obj)->fd = -1;
728 
729 	if (outbuf) {
730 		(*obj)->data = outbuf;
731 	} else {
732 		struct stat sb;
733 		if (fstat(*outfd, &sb) == -1) {
734 			err = got_error_from_errno("fstat");
735 			goto done;
736 		}
737 
738 		if (sb.st_size != hdrlen + size) {
739 			err = got_error(GOT_ERR_PRIVSEP_LEN);
740 			goto done;
741 		}
742 #ifndef GOT_PACK_NO_MMAP
743 		if (hdrlen + size > 0) {
744 			(*obj)->data = mmap(NULL, hdrlen + size, PROT_READ,
745 			    MAP_PRIVATE, *outfd, 0);
746 			if ((*obj)->data == MAP_FAILED) {
747 				if (errno != ENOMEM) {
748 					err = got_error_from_errno("mmap");
749 					goto done;
750 				}
751 				(*obj)->data = NULL;
752 			} else {
753 				(*obj)->fd = *outfd;
754 				*outfd = -1;
755 			}
756 		}
757 #endif
758 		if (*outfd != -1) {
759 			(*obj)->f = fdopen(*outfd, "r");
760 			if ((*obj)->f == NULL) {
761 				err = got_error_from_errno("fdopen");
762 				goto done;
763 			}
764 			*outfd = -1;
765 		}
766 	}
767 	(*obj)->hdrlen = hdrlen;
768 	(*obj)->size = size;
769 	err = got_repo_cache_raw_object(repo, id, *obj);
770 done:
771 	free(path_packfile);
772 	if (err) {
773 		if (*obj) {
774 			got_object_raw_close(*obj);
775 			*obj = NULL;
776 		}
777 		free(outbuf);
778 	} else
779 		(*obj)->refcnt++;
780 	return err;
781 }
782 
783 const struct got_error *
784 got_object_open_by_id_str(struct got_object **obj, struct got_repository *repo,
785     const char *id_str)
786 {
787 	struct got_object_id id;
788 
789 	if (!got_parse_sha1_digest(id.sha1, id_str))
790 		return got_error_path(id_str, GOT_ERR_BAD_OBJ_ID_STR);
791 
792 	return got_object_open(obj, repo, &id);
793 }
794 
795 const struct got_error *
796 got_object_resolve_id_str(struct got_object_id **id,
797     struct got_repository *repo, const char *id_str)
798 {
799 	const struct got_error *err = NULL;
800 	struct got_object *obj;
801 
802 	err = got_object_open_by_id_str(&obj, repo, id_str);
803 	if (err)
804 		return err;
805 
806 	*id = got_object_id_dup(got_object_get_id(obj));
807 	got_object_close(obj);
808 	if (*id == NULL)
809 		return got_error_from_errno("got_object_id_dup");
810 
811 	return NULL;
812 }
813 
814 static const struct got_error *
815 request_packed_commit(struct got_commit_object **commit, struct got_pack *pack,
816     int pack_idx, struct got_object_id *id)
817 {
818 	const struct got_error *err = NULL;
819 
820 	err = got_privsep_send_commit_req(pack->privsep_child->ibuf, -1, id,
821 	    pack_idx);
822 	if (err)
823 		return err;
824 
825 	err = got_privsep_recv_commit(commit, pack->privsep_child->ibuf);
826 	if (err)
827 		return err;
828 
829 	(*commit)->flags |= GOT_COMMIT_FLAG_PACKED;
830 	return NULL;
831 }
832 
833 static const struct got_error *
834 read_packed_commit_privsep(struct got_commit_object **commit,
835     struct got_pack *pack, struct got_packidx *packidx, int idx,
836     struct got_object_id *id)
837 {
838 	const struct got_error *err = NULL;
839 
840 	if (pack->privsep_child)
841 		return request_packed_commit(commit, pack, idx, id);
842 
843 	err = start_pack_privsep_child(pack, packidx);
844 	if (err)
845 		return err;
846 
847 	return request_packed_commit(commit, pack, idx, id);
848 }
849 
850 static const struct got_error *
851 request_commit(struct got_commit_object **commit, struct got_repository *repo,
852     int fd, struct got_object_id *id)
853 {
854 	const struct got_error *err = NULL;
855 	struct imsgbuf *ibuf;
856 
857 	ibuf = repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_COMMIT].ibuf;
858 
859 	err = got_privsep_send_commit_req(ibuf, fd, id, -1);
860 	if (err)
861 		return err;
862 
863 	return got_privsep_recv_commit(commit, ibuf);
864 }
865 
866 static const struct got_error *
867 read_commit_privsep(struct got_commit_object **commit, int obj_fd,
868     struct got_object_id *id, struct got_repository *repo)
869 {
870 	const struct got_error *err;
871 	int imsg_fds[2];
872 	pid_t pid;
873 	struct imsgbuf *ibuf;
874 
875 	if (repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_COMMIT].imsg_fd != -1)
876 		return request_commit(commit, repo, obj_fd, id);
877 
878 	ibuf = calloc(1, sizeof(*ibuf));
879 	if (ibuf == NULL)
880 		return got_error_from_errno("calloc");
881 
882 	if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, imsg_fds) == -1) {
883 		err = got_error_from_errno("socketpair");
884 		free(ibuf);
885 		return err;
886 	}
887 
888 	pid = fork();
889 	if (pid == -1) {
890 		err = got_error_from_errno("fork");
891 		free(ibuf);
892 		return err;
893 	}
894 	else if (pid == 0) {
895 		got_privsep_exec_child(imsg_fds, GOT_PATH_PROG_READ_COMMIT,
896 		    repo->path);
897 		/* not reached */
898 	}
899 
900 	if (close(imsg_fds[1]) == -1) {
901 		err = got_error_from_errno("close");
902 		free(ibuf);
903 		return err;
904 	}
905 	repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_COMMIT].imsg_fd =
906 	    imsg_fds[0];
907 	repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_COMMIT].pid = pid;
908 	imsg_init(ibuf, imsg_fds[0]);
909 	repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_COMMIT].ibuf = ibuf;
910 
911 	return request_commit(commit, repo, obj_fd, id);
912 }
913 
914 
915 static const struct got_error *
916 open_commit(struct got_commit_object **commit,
917     struct got_repository *repo, struct got_object_id *id, int check_cache)
918 {
919 	const struct got_error *err = NULL;
920 	struct got_packidx *packidx = NULL;
921 	int idx;
922 	char *path_packfile = NULL;
923 
924 	if (check_cache) {
925 		*commit = got_repo_get_cached_commit(repo, id);
926 		if (*commit != NULL) {
927 			(*commit)->refcnt++;
928 			return NULL;
929 		}
930 	} else
931 		*commit = NULL;
932 
933 	err = got_repo_search_packidx(&packidx, &idx, repo, id);
934 	if (err == NULL) {
935 		struct got_pack *pack = NULL;
936 
937 		err = got_packidx_get_packfile_path(&path_packfile,
938 		    packidx->path_packidx);
939 		if (err)
940 			return err;
941 
942 		pack = got_repo_get_cached_pack(repo, path_packfile);
943 		if (pack == NULL) {
944 			err = got_repo_cache_pack(&pack, repo, path_packfile,
945 			    packidx);
946 			if (err)
947 				goto done;
948 		}
949 		err = read_packed_commit_privsep(commit, pack,
950 		    packidx, idx, id);
951 	} else if (err->code == GOT_ERR_NO_OBJ) {
952 		int fd;
953 
954 		err = got_object_open_loose_fd(&fd, id, repo);
955 		if (err)
956 			return err;
957 		err = read_commit_privsep(commit, fd, id, repo);
958 	}
959 
960 	if (err == NULL) {
961 		(*commit)->refcnt++;
962 		err = got_repo_cache_commit(repo, id, *commit);
963 	}
964 done:
965 	free(path_packfile);
966 	return err;
967 }
968 
969 const struct got_error *
970 got_object_open_as_commit(struct got_commit_object **commit,
971     struct got_repository *repo, struct got_object_id *id)
972 {
973 	*commit = got_repo_get_cached_commit(repo, id);
974 	if (*commit != NULL) {
975 		(*commit)->refcnt++;
976 		return NULL;
977 	}
978 
979 	return open_commit(commit, repo, id, 0);
980 }
981 
982 const struct got_error *
983 got_object_commit_open(struct got_commit_object **commit,
984     struct got_repository *repo, struct got_object *obj)
985 {
986 	return open_commit(commit, repo, got_object_get_id(obj), 1);
987 }
988 
989 const struct got_error *
990 got_object_qid_alloc(struct got_object_qid **qid, struct got_object_id *id)
991 {
992 	*qid = calloc(1, sizeof(**qid));
993 	if (*qid == NULL)
994 		return got_error_from_errno("calloc");
995 
996 	memcpy(&(*qid)->id, id, sizeof((*qid)->id));
997 	return NULL;
998 }
999 
1000 const struct got_error *
1001 got_object_id_queue_copy(const struct got_object_id_queue *src,
1002     struct got_object_id_queue *dest)
1003 {
1004 	const struct got_error *err;
1005 	struct got_object_qid *qid;
1006 
1007 	STAILQ_FOREACH(qid, src, entry) {
1008 		struct got_object_qid *new;
1009 		/*
1010 		 * Deep-copy the object ID only. Let the caller deal
1011 		 * with setting up the new->data pointer if needed.
1012 		 */
1013 		err = got_object_qid_alloc(&new, &qid->id); 
1014 		if (err) {
1015 			got_object_id_queue_free(dest);
1016 			return err;
1017 		}
1018 		STAILQ_INSERT_TAIL(dest, new, entry);
1019 	}
1020 
1021 	return NULL;
1022 }
1023 
1024 static const struct got_error *
1025 request_packed_tree(struct got_tree_object **tree, struct got_pack *pack,
1026     int pack_idx, struct got_object_id *id)
1027 {
1028 	const struct got_error *err = NULL;
1029 
1030 	err = got_privsep_send_tree_req(pack->privsep_child->ibuf, -1, id,
1031 	    pack_idx);
1032 	if (err)
1033 		return err;
1034 
1035 	return got_privsep_recv_tree(tree, pack->privsep_child->ibuf);
1036 }
1037 
1038 static const struct got_error *
1039 read_packed_tree_privsep(struct got_tree_object **tree,
1040     struct got_pack *pack, struct got_packidx *packidx, int idx,
1041     struct got_object_id *id)
1042 {
1043 	const struct got_error *err = NULL;
1044 
1045 	if (pack->privsep_child)
1046 		return request_packed_tree(tree, pack, idx, id);
1047 
1048 	err = start_pack_privsep_child(pack, packidx);
1049 	if (err)
1050 		return err;
1051 
1052 	return request_packed_tree(tree, pack, idx, id);
1053 }
1054 
1055 static const struct got_error *
1056 request_tree(struct got_tree_object **tree, struct got_repository *repo,
1057     int fd, struct got_object_id *id)
1058 {
1059 	const struct got_error *err = NULL;
1060 	struct imsgbuf *ibuf;
1061 
1062 	ibuf = repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_TREE].ibuf;
1063 
1064 	err = got_privsep_send_tree_req(ibuf, fd, id, -1);
1065 	if (err)
1066 		return err;
1067 
1068 	return got_privsep_recv_tree(tree, ibuf);
1069 }
1070 
1071 const struct got_error *
1072 read_tree_privsep(struct got_tree_object **tree, int obj_fd,
1073     struct got_object_id *id, struct got_repository *repo)
1074 {
1075 	const struct got_error *err;
1076 	int imsg_fds[2];
1077 	pid_t pid;
1078 	struct imsgbuf *ibuf;
1079 
1080 	if (repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_TREE].imsg_fd != -1)
1081 		return request_tree(tree, repo, obj_fd, id);
1082 
1083 	ibuf = calloc(1, sizeof(*ibuf));
1084 	if (ibuf == NULL)
1085 		return got_error_from_errno("calloc");
1086 
1087 	if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, imsg_fds) == -1) {
1088 		err = got_error_from_errno("socketpair");
1089 		free(ibuf);
1090 		return err;
1091 	}
1092 
1093 	pid = fork();
1094 	if (pid == -1) {
1095 		err = got_error_from_errno("fork");
1096 		free(ibuf);
1097 		return err;
1098 	}
1099 	else if (pid == 0) {
1100 		got_privsep_exec_child(imsg_fds, GOT_PATH_PROG_READ_TREE,
1101 		    repo->path);
1102 		/* not reached */
1103 	}
1104 
1105 	if (close(imsg_fds[1]) == -1) {
1106 		err = got_error_from_errno("close");
1107 		free(ibuf);
1108 		return err;
1109 	}
1110 	repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_TREE].imsg_fd =
1111 	    imsg_fds[0];
1112 	repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_TREE].pid = pid;
1113 	imsg_init(ibuf, imsg_fds[0]);
1114 	repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_TREE].ibuf = ibuf;
1115 
1116 
1117 	return request_tree(tree, repo, obj_fd, id);
1118 }
1119 
1120 static const struct got_error *
1121 open_tree(struct got_tree_object **tree, struct got_repository *repo,
1122     struct got_object_id *id, int check_cache)
1123 {
1124 	const struct got_error *err = NULL;
1125 	struct got_packidx *packidx = NULL;
1126 	int idx;
1127 	char *path_packfile = NULL;
1128 
1129 	if (check_cache) {
1130 		*tree = got_repo_get_cached_tree(repo, id);
1131 		if (*tree != NULL) {
1132 			(*tree)->refcnt++;
1133 			return NULL;
1134 		}
1135 	} else
1136 		*tree = NULL;
1137 
1138 	err = got_repo_search_packidx(&packidx, &idx, repo, id);
1139 	if (err == NULL) {
1140 		struct got_pack *pack = NULL;
1141 
1142 		err = got_packidx_get_packfile_path(&path_packfile,
1143 		    packidx->path_packidx);
1144 		if (err)
1145 			return err;
1146 
1147 		pack = got_repo_get_cached_pack(repo, path_packfile);
1148 		if (pack == NULL) {
1149 			err = got_repo_cache_pack(&pack, repo, path_packfile,
1150 			    packidx);
1151 			if (err)
1152 				goto done;
1153 		}
1154 		err = read_packed_tree_privsep(tree, pack,
1155 		    packidx, idx, id);
1156 	} else if (err->code == GOT_ERR_NO_OBJ) {
1157 		int fd;
1158 
1159 		err = got_object_open_loose_fd(&fd, id, repo);
1160 		if (err)
1161 			return err;
1162 		err = read_tree_privsep(tree, fd, id, repo);
1163 	}
1164 
1165 	if (err == NULL) {
1166 		(*tree)->refcnt++;
1167 		err = got_repo_cache_tree(repo, id, *tree);
1168 	}
1169 done:
1170 	free(path_packfile);
1171 	return err;
1172 }
1173 
1174 const struct got_error *
1175 got_object_open_as_tree(struct got_tree_object **tree,
1176     struct got_repository *repo, struct got_object_id *id)
1177 {
1178 	*tree = got_repo_get_cached_tree(repo, id);
1179 	if (*tree != NULL) {
1180 		(*tree)->refcnt++;
1181 		return NULL;
1182 	}
1183 
1184 	return open_tree(tree, repo, id, 0);
1185 }
1186 
1187 const struct got_error *
1188 got_object_tree_open(struct got_tree_object **tree,
1189     struct got_repository *repo, struct got_object *obj)
1190 {
1191 	return open_tree(tree, repo, got_object_get_id(obj), 1);
1192 }
1193 
1194 int
1195 got_object_tree_get_nentries(struct got_tree_object *tree)
1196 {
1197 	return tree->nentries;
1198 }
1199 
1200 struct got_tree_entry *
1201 got_object_tree_get_first_entry(struct got_tree_object *tree)
1202 {
1203 	return got_object_tree_get_entry(tree, 0);
1204 }
1205 
1206 struct got_tree_entry *
1207 got_object_tree_get_last_entry(struct got_tree_object *tree)
1208 {
1209 	return got_object_tree_get_entry(tree, tree->nentries - 1);
1210 }
1211 
1212 struct got_tree_entry *
1213 got_object_tree_get_entry(struct got_tree_object *tree, int i)
1214 {
1215 	if (i < 0 || i >= tree->nentries)
1216 		return NULL;
1217 	return &tree->entries[i];
1218 }
1219 
1220 mode_t
1221 got_tree_entry_get_mode(struct got_tree_entry *te)
1222 {
1223 	return te->mode;
1224 }
1225 
1226 const char *
1227 got_tree_entry_get_name(struct got_tree_entry *te)
1228 {
1229 	return &te->name[0];
1230 }
1231 
1232 struct got_object_id *
1233 got_tree_entry_get_id(struct got_tree_entry *te)
1234 {
1235 	return &te->id;
1236 }
1237 
1238 const struct got_error *
1239 got_object_blob_read_to_str(char **s, struct got_blob_object *blob)
1240 {
1241 	const struct got_error *err = NULL;
1242 	size_t len, totlen, hdrlen, offset;
1243 
1244 	*s = NULL;
1245 
1246 	hdrlen = got_object_blob_get_hdrlen(blob);
1247 	totlen = 0;
1248 	offset = 0;
1249 	do {
1250 		char *p;
1251 
1252 		err = got_object_blob_read_block(&len, blob);
1253 		if (err)
1254 			return err;
1255 
1256 		if (len == 0)
1257 			break;
1258 
1259 		totlen += len - hdrlen;
1260 		p = realloc(*s, totlen + 1);
1261 		if (p == NULL) {
1262 			err = got_error_from_errno("realloc");
1263 			free(*s);
1264 			*s = NULL;
1265 			return err;
1266 		}
1267 		*s = p;
1268 		/* Skip blob object header first time around. */
1269 		memcpy(*s + offset,
1270 		    got_object_blob_get_read_buf(blob) + hdrlen, len - hdrlen);
1271 		hdrlen = 0;
1272 		offset = totlen;
1273 	} while (len > 0);
1274 
1275 	(*s)[totlen] = '\0';
1276 	return NULL;
1277 }
1278 
1279 const struct got_error *
1280 got_tree_entry_get_symlink_target(char **link_target, struct got_tree_entry *te,
1281     struct got_repository *repo)
1282 {
1283 	const struct got_error *err = NULL;
1284 	struct got_blob_object *blob = NULL;
1285 
1286 	*link_target = NULL;
1287 
1288 	if (!got_object_tree_entry_is_symlink(te))
1289 		return got_error(GOT_ERR_TREE_ENTRY_TYPE);
1290 
1291 	err = got_object_open_as_blob(&blob, repo,
1292 	    got_tree_entry_get_id(te), PATH_MAX);
1293 	if (err)
1294 		return err;
1295 
1296 	err = got_object_blob_read_to_str(link_target, blob);
1297 	got_object_blob_close(blob);
1298 	if (err) {
1299 		free(*link_target);
1300 		*link_target = NULL;
1301 	}
1302 	return err;
1303 }
1304 
1305 int
1306 got_tree_entry_get_index(struct got_tree_entry *te)
1307 {
1308 	return te->idx;
1309 }
1310 
1311 struct got_tree_entry *
1312 got_tree_entry_get_next(struct got_tree_object *tree,
1313     struct got_tree_entry *te)
1314 {
1315 	return got_object_tree_get_entry(tree, te->idx + 1);
1316 }
1317 
1318 struct got_tree_entry *
1319 got_tree_entry_get_prev(struct got_tree_object *tree,
1320     struct got_tree_entry *te)
1321 {
1322 	return got_object_tree_get_entry(tree, te->idx - 1);
1323 }
1324 
1325 static const struct got_error *
1326 request_packed_blob(uint8_t **outbuf, size_t *size, size_t *hdrlen, int outfd,
1327     struct got_pack *pack, struct got_packidx *packidx, int idx,
1328     struct got_object_id *id)
1329 {
1330 	const struct got_error *err = NULL;
1331 	struct imsgbuf *ibuf = pack->privsep_child->ibuf;
1332 	int outfd_child;
1333 
1334 	 err = pack_child_send_tempfiles(ibuf, pack);
1335 	 if (err)
1336 		return err;
1337 
1338 	outfd_child = dup(outfd);
1339 	if (outfd_child == -1)
1340 		return got_error_from_errno("dup");
1341 
1342 	err = got_privsep_send_blob_req(pack->privsep_child->ibuf, -1, id, idx);
1343 	if (err)
1344 		return err;
1345 
1346 	err = got_privsep_send_blob_outfd(pack->privsep_child->ibuf,
1347 	    outfd_child);
1348 	if (err) {
1349 		return err;
1350 	}
1351 
1352 	err = got_privsep_recv_blob(outbuf, size, hdrlen,
1353 	    pack->privsep_child->ibuf);
1354 	if (err)
1355 		return err;
1356 
1357 	if (lseek(outfd, SEEK_SET, 0) == -1)
1358 		err = got_error_from_errno("lseek");
1359 
1360 	return err;
1361 }
1362 
1363 static const struct got_error *
1364 read_packed_blob_privsep(uint8_t **outbuf, size_t *size, size_t *hdrlen,
1365     int outfd, struct got_pack *pack, struct got_packidx *packidx, int idx,
1366     struct got_object_id *id)
1367 {
1368 	const struct got_error *err = NULL;
1369 
1370 	if (pack->privsep_child == NULL) {
1371 		err = start_pack_privsep_child(pack, packidx);
1372 		if (err)
1373 			return err;
1374 	}
1375 
1376 	return request_packed_blob(outbuf, size, hdrlen, outfd, pack, packidx,
1377 	    idx, id);
1378 }
1379 
1380 static const struct got_error *
1381 request_blob(uint8_t **outbuf, size_t *size, size_t *hdrlen, int outfd,
1382     int infd, struct got_object_id *id, struct imsgbuf *ibuf)
1383 {
1384 	const struct got_error *err = NULL;
1385 	int outfd_child;
1386 
1387 	outfd_child = dup(outfd);
1388 	if (outfd_child == -1)
1389 		return got_error_from_errno("dup");
1390 
1391 	err = got_privsep_send_blob_req(ibuf, infd, id, -1);
1392 	if (err)
1393 		return err;
1394 
1395 	err = got_privsep_send_blob_outfd(ibuf, outfd_child);
1396 	if (err)
1397 		return err;
1398 
1399 	err = got_privsep_recv_blob(outbuf, size, hdrlen, ibuf);
1400 	if (err)
1401 		return err;
1402 
1403 	if (lseek(outfd, SEEK_SET, 0) == -1)
1404 		return got_error_from_errno("lseek");
1405 
1406 	return err;
1407 }
1408 
1409 static const struct got_error *
1410 read_blob_privsep(uint8_t **outbuf, size_t *size, size_t *hdrlen,
1411     int outfd, int infd, struct got_object_id *id, struct got_repository *repo)
1412 {
1413 	const struct got_error *err;
1414 	int imsg_fds[2];
1415 	pid_t pid;
1416 	struct imsgbuf *ibuf;
1417 
1418 	if (repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_BLOB].imsg_fd != -1) {
1419 		ibuf = repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_BLOB].ibuf;
1420 		return request_blob(outbuf, size, hdrlen, outfd, infd, id,
1421 		    ibuf);
1422 	}
1423 
1424 	ibuf = calloc(1, sizeof(*ibuf));
1425 	if (ibuf == NULL)
1426 		return got_error_from_errno("calloc");
1427 
1428 	if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, imsg_fds) == -1) {
1429 		err = got_error_from_errno("socketpair");
1430 		free(ibuf);
1431 		return err;
1432 	}
1433 
1434 	pid = fork();
1435 	if (pid == -1) {
1436 		err = got_error_from_errno("fork");
1437 		free(ibuf);
1438 		return err;
1439 	}
1440 	else if (pid == 0) {
1441 		got_privsep_exec_child(imsg_fds, GOT_PATH_PROG_READ_BLOB,
1442 		    repo->path);
1443 		/* not reached */
1444 	}
1445 
1446 	if (close(imsg_fds[1]) == -1) {
1447 		err = got_error_from_errno("close");
1448 		free(ibuf);
1449 		return err;
1450 	}
1451 	repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_BLOB].imsg_fd =
1452 	    imsg_fds[0];
1453 	repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_BLOB].pid = pid;
1454 	imsg_init(ibuf, imsg_fds[0]);
1455 	repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_BLOB].ibuf = ibuf;
1456 
1457 	return request_blob(outbuf, size, hdrlen, outfd, infd, id, ibuf);
1458 }
1459 
1460 static const struct got_error *
1461 open_blob(struct got_blob_object **blob, struct got_repository *repo,
1462     struct got_object_id *id, size_t blocksize)
1463 {
1464 	const struct got_error *err = NULL;
1465 	struct got_packidx *packidx = NULL;
1466 	int idx;
1467 	char *path_packfile = NULL;
1468 	uint8_t *outbuf;
1469 	int outfd;
1470 	size_t size, hdrlen;
1471 	struct stat sb;
1472 
1473 	*blob = calloc(1, sizeof(**blob));
1474 	if (*blob == NULL)
1475 		return got_error_from_errno("calloc");
1476 
1477 	outfd = got_opentempfd();
1478 	if (outfd == -1)
1479 		return got_error_from_errno("got_opentempfd");
1480 
1481 	(*blob)->read_buf = malloc(blocksize);
1482 	if ((*blob)->read_buf == NULL) {
1483 		err = got_error_from_errno("malloc");
1484 		goto done;
1485 	}
1486 
1487 	err = got_repo_search_packidx(&packidx, &idx, repo, id);
1488 	if (err == NULL) {
1489 		struct got_pack *pack = NULL;
1490 
1491 		err = got_packidx_get_packfile_path(&path_packfile,
1492 		    packidx->path_packidx);
1493 		if (err)
1494 			goto done;
1495 
1496 		pack = got_repo_get_cached_pack(repo, path_packfile);
1497 		if (pack == NULL) {
1498 			err = got_repo_cache_pack(&pack, repo, path_packfile,
1499 			    packidx);
1500 			if (err)
1501 				goto done;
1502 		}
1503 		err = read_packed_blob_privsep(&outbuf, &size, &hdrlen, outfd,
1504 		    pack, packidx, idx, id);
1505 	} else if (err->code == GOT_ERR_NO_OBJ) {
1506 		int infd;
1507 
1508 		err = got_object_open_loose_fd(&infd, id, repo);
1509 		if (err)
1510 			goto done;
1511 		err = read_blob_privsep(&outbuf, &size, &hdrlen, outfd, infd,
1512 		    id, repo);
1513 	}
1514 	if (err)
1515 		goto done;
1516 
1517 	if (hdrlen > size) {
1518 		err = got_error(GOT_ERR_BAD_OBJ_HDR);
1519 		goto done;
1520 	}
1521 
1522 	if (outbuf) {
1523 		if (close(outfd) == -1 && err == NULL)
1524 			err = got_error_from_errno("close");
1525 		outfd = -1;
1526 		(*blob)->f = fmemopen(outbuf, size, "rb");
1527 		if ((*blob)->f == NULL) {
1528 			err = got_error_from_errno("fmemopen");
1529 			free(outbuf);
1530 			goto done;
1531 		}
1532 		(*blob)->data = outbuf;
1533 	} else {
1534 		if (fstat(outfd, &sb) == -1) {
1535 			err = got_error_from_errno("fstat");
1536 			goto done;
1537 		}
1538 
1539 		if (sb.st_size != size) {
1540 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1541 			goto done;
1542 		}
1543 
1544 		(*blob)->f = fdopen(outfd, "rb");
1545 		if ((*blob)->f == NULL) {
1546 			err = got_error_from_errno("fdopen");
1547 			close(outfd);
1548 			outfd = -1;
1549 			goto done;
1550 		}
1551 	}
1552 
1553 	(*blob)->hdrlen = hdrlen;
1554 	(*blob)->blocksize = blocksize;
1555 	memcpy(&(*blob)->id.sha1, id->sha1, SHA1_DIGEST_LENGTH);
1556 
1557 done:
1558 	free(path_packfile);
1559 	if (err) {
1560 		if (*blob) {
1561 			got_object_blob_close(*blob);
1562 			*blob = NULL;
1563 		} else if (outfd != -1)
1564 			close(outfd);
1565 	}
1566 	return err;
1567 }
1568 
1569 const struct got_error *
1570 got_object_open_as_blob(struct got_blob_object **blob,
1571     struct got_repository *repo, struct got_object_id *id,
1572     size_t blocksize)
1573 {
1574 	return open_blob(blob, repo, id, blocksize);
1575 }
1576 
1577 const struct got_error *
1578 got_object_blob_open(struct got_blob_object **blob,
1579     struct got_repository *repo, struct got_object *obj, size_t blocksize)
1580 {
1581 	return open_blob(blob, repo, got_object_get_id(obj), blocksize);
1582 }
1583 
1584 const struct got_error *
1585 got_object_blob_close(struct got_blob_object *blob)
1586 {
1587 	const struct got_error *err = NULL;
1588 	free(blob->read_buf);
1589 	if (blob->f && fclose(blob->f) == EOF)
1590 		err = got_error_from_errno("fclose");
1591 	free(blob->data);
1592 	free(blob);
1593 	return err;
1594 }
1595 
1596 void
1597 got_object_blob_rewind(struct got_blob_object *blob)
1598 {
1599 	if (blob->f)
1600 		rewind(blob->f);
1601 }
1602 
1603 char *
1604 got_object_blob_id_str(struct got_blob_object *blob, char *buf, size_t size)
1605 {
1606 	return got_sha1_digest_to_str(blob->id.sha1, buf, size);
1607 }
1608 
1609 size_t
1610 got_object_blob_get_hdrlen(struct got_blob_object *blob)
1611 {
1612 	return blob->hdrlen;
1613 }
1614 
1615 const uint8_t *
1616 got_object_blob_get_read_buf(struct got_blob_object *blob)
1617 {
1618 	return blob->read_buf;
1619 }
1620 
1621 const struct got_error *
1622 got_object_blob_read_block(size_t *outlenp, struct got_blob_object *blob)
1623 {
1624 	size_t n;
1625 
1626 	n = fread(blob->read_buf, 1, blob->blocksize, blob->f);
1627 	if (n == 0 && ferror(blob->f))
1628 		return got_ferror(blob->f, GOT_ERR_IO);
1629 	*outlenp = n;
1630 	return NULL;
1631 }
1632 
1633 const struct got_error *
1634 got_object_blob_dump_to_file(off_t *filesize, int *nlines,
1635     off_t **line_offsets, FILE *outfile, struct got_blob_object *blob)
1636 {
1637 	const struct got_error *err = NULL;
1638 	size_t n, len, hdrlen;
1639 	const uint8_t *buf;
1640 	int i;
1641 	const int alloc_chunksz = 512;
1642 	size_t nalloc = 0;
1643 	off_t off = 0, total_len = 0;
1644 
1645 	if (line_offsets)
1646 		*line_offsets = NULL;
1647 	if (filesize)
1648 		*filesize = 0;
1649 	if (nlines)
1650 		*nlines = 0;
1651 
1652 	hdrlen = got_object_blob_get_hdrlen(blob);
1653 	do {
1654 		err = got_object_blob_read_block(&len, blob);
1655 		if (err)
1656 			return err;
1657 		if (len == 0)
1658 			break;
1659 		buf = got_object_blob_get_read_buf(blob);
1660 		i = hdrlen;
1661 		if (nlines) {
1662 			if (line_offsets && *line_offsets == NULL) {
1663 				/* Have some data but perhaps no '\n'. */
1664 				*nlines = 1;
1665 				nalloc = alloc_chunksz;
1666 				*line_offsets = calloc(nalloc,
1667 				    sizeof(**line_offsets));
1668 				if (*line_offsets == NULL)
1669 					return got_error_from_errno("calloc");
1670 
1671 				/* Skip forward over end of first line. */
1672 				while (i < len) {
1673 					if (buf[i] == '\n')
1674 						break;
1675 					i++;
1676 				}
1677 			}
1678 			/* Scan '\n' offsets in remaining chunk of data. */
1679 			while (i < len) {
1680 				if (buf[i] != '\n') {
1681 					i++;
1682 					continue;
1683 				}
1684 				(*nlines)++;
1685 				if (line_offsets && nalloc < *nlines) {
1686 					size_t n = *nlines + alloc_chunksz;
1687 					off_t *o = recallocarray(*line_offsets,
1688 					    nalloc, n, sizeof(**line_offsets));
1689 					if (o == NULL) {
1690 						free(*line_offsets);
1691 						*line_offsets = NULL;
1692 						return got_error_from_errno(
1693 						    "recallocarray");
1694 					}
1695 					*line_offsets = o;
1696 					nalloc = n;
1697 				}
1698 				if (line_offsets) {
1699 					off = total_len + i - hdrlen + 1;
1700 					(*line_offsets)[*nlines - 1] = off;
1701 				}
1702 				i++;
1703 			}
1704 		}
1705 		/* Skip blob object header first time around. */
1706 		n = fwrite(buf + hdrlen, 1, len - hdrlen, outfile);
1707 		if (n != len - hdrlen)
1708 			return got_ferror(outfile, GOT_ERR_IO);
1709 		total_len += len - hdrlen;
1710 		hdrlen = 0;
1711 	} while (len != 0);
1712 
1713 	if (fflush(outfile) != 0)
1714 		return got_error_from_errno("fflush");
1715 	rewind(outfile);
1716 
1717 	if (filesize)
1718 		*filesize = total_len;
1719 
1720 	return NULL;
1721 }
1722 
1723 static const struct got_error *
1724 request_packed_tag(struct got_tag_object **tag, struct got_pack *pack,
1725     int pack_idx, struct got_object_id *id)
1726 {
1727 	const struct got_error *err = NULL;
1728 
1729 	err = got_privsep_send_tag_req(pack->privsep_child->ibuf, -1, id,
1730 	    pack_idx);
1731 	if (err)
1732 		return err;
1733 
1734 	return got_privsep_recv_tag(tag, pack->privsep_child->ibuf);
1735 }
1736 
1737 static const struct got_error *
1738 read_packed_tag_privsep(struct got_tag_object **tag,
1739     struct got_pack *pack, struct got_packidx *packidx, int idx,
1740     struct got_object_id *id)
1741 {
1742 	const struct got_error *err = NULL;
1743 
1744 	if (pack->privsep_child)
1745 		return request_packed_tag(tag, pack, idx, id);
1746 
1747 	err = start_pack_privsep_child(pack, packidx);
1748 	if (err)
1749 		return err;
1750 
1751 	return request_packed_tag(tag, pack, idx, id);
1752 }
1753 
1754 static const struct got_error *
1755 request_tag(struct got_tag_object **tag, struct got_repository *repo,
1756     int fd, struct got_object_id *id)
1757 {
1758 	const struct got_error *err = NULL;
1759 	struct imsgbuf *ibuf;
1760 
1761 	ibuf = repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_TAG].ibuf;
1762 
1763 	err = got_privsep_send_tag_req(ibuf, fd, id, -1);
1764 	if (err)
1765 		return err;
1766 
1767 	return got_privsep_recv_tag(tag, ibuf);
1768 }
1769 
1770 static const struct got_error *
1771 read_tag_privsep(struct got_tag_object **tag, int obj_fd,
1772     struct got_object_id *id, struct got_repository *repo)
1773 {
1774 	const struct got_error *err;
1775 	int imsg_fds[2];
1776 	pid_t pid;
1777 	struct imsgbuf *ibuf;
1778 
1779 	if (repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_TAG].imsg_fd != -1)
1780 		return request_tag(tag, repo, obj_fd, id);
1781 
1782 	ibuf = calloc(1, sizeof(*ibuf));
1783 	if (ibuf == NULL)
1784 		return got_error_from_errno("calloc");
1785 
1786 	if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, imsg_fds) == -1) {
1787 		err = got_error_from_errno("socketpair");
1788 		free(ibuf);
1789 		return err;
1790 	}
1791 
1792 	pid = fork();
1793 	if (pid == -1) {
1794 		err = got_error_from_errno("fork");
1795 		free(ibuf);
1796 		return err;
1797 	}
1798 	else if (pid == 0) {
1799 		got_privsep_exec_child(imsg_fds, GOT_PATH_PROG_READ_TAG,
1800 		    repo->path);
1801 		/* not reached */
1802 	}
1803 
1804 	if (close(imsg_fds[1]) == -1) {
1805 		err = got_error_from_errno("close");
1806 		free(ibuf);
1807 		return err;
1808 	}
1809 	repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_TAG].imsg_fd =
1810 	    imsg_fds[0];
1811 	repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_TAG].pid = pid;
1812 	imsg_init(ibuf, imsg_fds[0]);
1813 	repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_TAG].ibuf = ibuf;
1814 
1815 	return request_tag(tag, repo, obj_fd, id);
1816 }
1817 
1818 static const struct got_error *
1819 open_tag(struct got_tag_object **tag, struct got_repository *repo,
1820     struct got_object_id *id, int check_cache)
1821 {
1822 	const struct got_error *err = NULL;
1823 	struct got_packidx *packidx = NULL;
1824 	int idx;
1825 	char *path_packfile = NULL;
1826 	struct got_object *obj = NULL;
1827 	int obj_type = GOT_OBJ_TYPE_ANY;
1828 
1829 	if (check_cache) {
1830 		*tag = got_repo_get_cached_tag(repo, id);
1831 		if (*tag != NULL) {
1832 			(*tag)->refcnt++;
1833 			return NULL;
1834 		}
1835 	} else
1836 		*tag = NULL;
1837 
1838 	err = got_repo_search_packidx(&packidx, &idx, repo, id);
1839 	if (err == NULL) {
1840 		struct got_pack *pack = NULL;
1841 
1842 		err = got_packidx_get_packfile_path(&path_packfile,
1843 		    packidx->path_packidx);
1844 		if (err)
1845 			return err;
1846 
1847 		pack = got_repo_get_cached_pack(repo, path_packfile);
1848 		if (pack == NULL) {
1849 			err = got_repo_cache_pack(&pack, repo, path_packfile,
1850 			    packidx);
1851 			if (err)
1852 				goto done;
1853 		}
1854 
1855 		/* Beware of "lightweight" tags: Check object type first. */
1856 		err = read_packed_object_privsep(&obj, repo, pack, packidx,
1857 		    idx, id);
1858 		if (err)
1859 			goto done;
1860 		obj_type = obj->type;
1861 		got_object_close(obj);
1862 		if (obj_type != GOT_OBJ_TYPE_TAG) {
1863 			err = got_error(GOT_ERR_OBJ_TYPE);
1864 			goto done;
1865 		}
1866 		err = read_packed_tag_privsep(tag, pack, packidx, idx, id);
1867 	} else if (err->code == GOT_ERR_NO_OBJ) {
1868 		int fd;
1869 
1870 		err = got_object_open_loose_fd(&fd, id, repo);
1871 		if (err)
1872 			return err;
1873 		err = got_object_read_header_privsep(&obj, id, repo, fd);
1874 		if (err)
1875 			return err;
1876 		obj_type = obj->type;
1877 		got_object_close(obj);
1878 		if (obj_type != GOT_OBJ_TYPE_TAG)
1879 			return got_error(GOT_ERR_OBJ_TYPE);
1880 
1881 		err = got_object_open_loose_fd(&fd, id, repo);
1882 		if (err)
1883 			return err;
1884 		err = read_tag_privsep(tag, fd, id, repo);
1885 	}
1886 
1887 	if (err == NULL) {
1888 		(*tag)->refcnt++;
1889 		err = got_repo_cache_tag(repo, id, *tag);
1890 	}
1891 done:
1892 	free(path_packfile);
1893 	return err;
1894 }
1895 
1896 const struct got_error *
1897 got_object_open_as_tag(struct got_tag_object **tag,
1898     struct got_repository *repo, struct got_object_id *id)
1899 {
1900 	*tag = got_repo_get_cached_tag(repo, id);
1901 	if (*tag != NULL) {
1902 		(*tag)->refcnt++;
1903 		return NULL;
1904 	}
1905 
1906 	return open_tag(tag, repo, id, 0);
1907 }
1908 
1909 const struct got_error *
1910 got_object_tag_open(struct got_tag_object **tag,
1911     struct got_repository *repo, struct got_object *obj)
1912 {
1913 	return open_tag(tag, repo, got_object_get_id(obj), 1);
1914 }
1915 
1916 const char *
1917 got_object_tag_get_name(struct got_tag_object *tag)
1918 {
1919 	return tag->tag;
1920 }
1921 
1922 int
1923 got_object_tag_get_object_type(struct got_tag_object *tag)
1924 {
1925 	return tag->obj_type;
1926 }
1927 
1928 struct got_object_id *
1929 got_object_tag_get_object_id(struct got_tag_object *tag)
1930 {
1931 	return &tag->id;
1932 }
1933 
1934 time_t
1935 got_object_tag_get_tagger_time(struct got_tag_object *tag)
1936 {
1937 	return tag->tagger_time;
1938 }
1939 
1940 time_t
1941 got_object_tag_get_tagger_gmtoff(struct got_tag_object *tag)
1942 {
1943 	return tag->tagger_gmtoff;
1944 }
1945 
1946 const char *
1947 got_object_tag_get_tagger(struct got_tag_object *tag)
1948 {
1949 	return tag->tagger;
1950 }
1951 
1952 const char *
1953 got_object_tag_get_message(struct got_tag_object *tag)
1954 {
1955 	return tag->tagmsg;
1956 }
1957 
1958 static struct got_tree_entry *
1959 find_entry_by_name(struct got_tree_object *tree, const char *name, size_t len)
1960 {
1961 	int i;
1962 
1963 	/* Note that tree entries are sorted in strncmp() order. */
1964 	for (i = 0; i < tree->nentries; i++) {
1965 		struct got_tree_entry *te = &tree->entries[i];
1966 		int cmp = strncmp(te->name, name, len);
1967 		if (cmp < 0)
1968 			continue;
1969 		if (cmp > 0)
1970 			break;
1971 		if (te->name[len] == '\0')
1972 			return te;
1973 	}
1974 	return NULL;
1975 }
1976 
1977 struct got_tree_entry *
1978 got_object_tree_find_entry(struct got_tree_object *tree, const char *name)
1979 {
1980 	return find_entry_by_name(tree, name, strlen(name));
1981 }
1982 
1983 const struct got_error *
1984 got_object_tree_find_path(struct got_object_id **id, mode_t *mode,
1985     struct got_repository *repo, struct got_tree_object *tree,
1986     const char *path)
1987 {
1988 	const struct got_error *err = NULL;
1989 	struct got_tree_object *subtree = NULL;
1990 	struct got_tree_entry *te = NULL;
1991 	const char *seg, *s;
1992 	size_t seglen;
1993 
1994 	*id = NULL;
1995 
1996 	s = path;
1997 	while (s[0] == '/')
1998 		s++;
1999 	seg = s;
2000 	seglen = 0;
2001 	subtree = tree;
2002 	while (*s) {
2003 		struct got_tree_object *next_tree;
2004 
2005 		if (*s != '/') {
2006 			s++;
2007 			seglen++;
2008 			if (*s)
2009 				continue;
2010 		}
2011 
2012 		te = find_entry_by_name(subtree, seg, seglen);
2013 		if (te == NULL) {
2014 			err = got_error_path(path, GOT_ERR_NO_TREE_ENTRY);
2015 			goto done;
2016 		}
2017 
2018 		if (*s == '\0')
2019 			break;
2020 
2021 		seg = s + 1;
2022 		seglen = 0;
2023 		s++;
2024 		if (*s) {
2025 			err = got_object_open_as_tree(&next_tree, repo,
2026 			    &te->id);
2027 			te = NULL;
2028 			if (err)
2029 				goto done;
2030 			if (subtree != tree)
2031 				got_object_tree_close(subtree);
2032 			subtree = next_tree;
2033 		}
2034 	}
2035 
2036 	if (te) {
2037 		*id = got_object_id_dup(&te->id);
2038 		if (*id == NULL)
2039 			return got_error_from_errno("got_object_id_dup");
2040 		if (mode)
2041 			*mode = te->mode;
2042 	} else
2043 		err = got_error_path(path, GOT_ERR_NO_TREE_ENTRY);
2044 done:
2045 	if (subtree && subtree != tree)
2046 		got_object_tree_close(subtree);
2047 	return err;
2048 }
2049 const struct got_error *
2050 got_object_id_by_path(struct got_object_id **id, struct got_repository *repo,
2051     struct got_commit_object *commit, const char *path)
2052 {
2053 	const struct got_error *err = NULL;
2054 	struct got_tree_object *tree = NULL;
2055 
2056 	*id = NULL;
2057 
2058 	/* Handle opening of root of commit's tree. */
2059 	if (got_path_is_root_dir(path)) {
2060 		*id = got_object_id_dup(commit->tree_id);
2061 		if (*id == NULL)
2062 			err = got_error_from_errno("got_object_id_dup");
2063 	} else {
2064 		err = got_object_open_as_tree(&tree, repo, commit->tree_id);
2065 		if (err)
2066 			goto done;
2067 		err = got_object_tree_find_path(id, NULL, repo, tree, path);
2068 	}
2069 done:
2070 	if (tree)
2071 		got_object_tree_close(tree);
2072 	return err;
2073 }
2074 
2075 /*
2076  * Normalize file mode bits to avoid false positive tree entry differences
2077  * in case tree entries have unexpected mode bits set.
2078  */
2079 static mode_t
2080 normalize_mode_for_comparison(mode_t mode)
2081 {
2082 	/*
2083 	 * For directories, the only relevant bit is the IFDIR bit.
2084 	 * This allows us to detect paths changing from a directory
2085 	 * to a file and vice versa.
2086 	 */
2087 	if (S_ISDIR(mode))
2088 		return mode & S_IFDIR;
2089 
2090 	/*
2091 	 * For symlinks, the only relevant bit is the IFLNK bit.
2092 	 * This allows us to detect paths changing from a symlinks
2093 	 * to a file or directory and vice versa.
2094 	 */
2095 	if (S_ISLNK(mode))
2096 		return mode & S_IFLNK;
2097 
2098 	/* For files, the only change we care about is the executable bit. */
2099 	return mode & S_IXUSR;
2100 }
2101 
2102 const struct got_error *
2103 got_object_tree_path_changed(int *changed,
2104     struct got_tree_object *tree01, struct got_tree_object *tree02,
2105     const char *path, struct got_repository *repo)
2106 {
2107 	const struct got_error *err = NULL;
2108 	struct got_tree_object *tree1 = NULL, *tree2 = NULL;
2109 	struct got_tree_entry *te1 = NULL, *te2 = NULL;
2110 	const char *seg, *s;
2111 	size_t seglen;
2112 
2113 	*changed = 0;
2114 
2115 	/* We not do support comparing the root path. */
2116 	if (got_path_is_root_dir(path))
2117 		return got_error_path(path, GOT_ERR_BAD_PATH);
2118 
2119 	tree1 = tree01;
2120 	tree2 = tree02;
2121 	s = path;
2122 	while (*s == '/')
2123 		s++;
2124 	seg = s;
2125 	seglen = 0;
2126 	while (*s) {
2127 		struct got_tree_object *next_tree1, *next_tree2;
2128 		mode_t mode1, mode2;
2129 
2130 		if (*s != '/') {
2131 			s++;
2132 			seglen++;
2133 			if (*s)
2134 				continue;
2135 		}
2136 
2137 		te1 = find_entry_by_name(tree1, seg, seglen);
2138 		if (te1 == NULL) {
2139 			err = got_error(GOT_ERR_NO_OBJ);
2140 			goto done;
2141 		}
2142 
2143 		if (tree2)
2144 			te2 = find_entry_by_name(tree2, seg, seglen);
2145 
2146 		if (te2) {
2147 			mode1 = normalize_mode_for_comparison(te1->mode);
2148 			mode2 = normalize_mode_for_comparison(te2->mode);
2149 			if (mode1 != mode2) {
2150 				*changed = 1;
2151 				goto done;
2152 			}
2153 
2154 			if (got_object_id_cmp(&te1->id, &te2->id) == 0) {
2155 				*changed = 0;
2156 				goto done;
2157 			}
2158 		}
2159 
2160 		if (*s == '\0') { /* final path element */
2161 			*changed = 1;
2162 			goto done;
2163 		}
2164 
2165 		seg = s + 1;
2166 		s++;
2167 		seglen = 0;
2168 		if (*s) {
2169 			err = got_object_open_as_tree(&next_tree1, repo,
2170 			    &te1->id);
2171 			te1 = NULL;
2172 			if (err)
2173 				goto done;
2174 			if (tree1 != tree01)
2175 				got_object_tree_close(tree1);
2176 			tree1 = next_tree1;
2177 
2178 			if (te2) {
2179 				err = got_object_open_as_tree(&next_tree2, repo,
2180 				    &te2->id);
2181 				te2 = NULL;
2182 				if (err)
2183 					goto done;
2184 				if (tree2 != tree02)
2185 					got_object_tree_close(tree2);
2186 				tree2 = next_tree2;
2187 			} else if (tree2) {
2188 				if (tree2 != tree02)
2189 					got_object_tree_close(tree2);
2190 				tree2 = NULL;
2191 			}
2192 		}
2193 	}
2194 done:
2195 	if (tree1 && tree1 != tree01)
2196 		got_object_tree_close(tree1);
2197 	if (tree2 && tree2 != tree02)
2198 		got_object_tree_close(tree2);
2199 	return err;
2200 }
2201 
2202 const struct got_error *
2203 got_object_tree_entry_dup(struct got_tree_entry **new_te,
2204     struct got_tree_entry *te)
2205 {
2206 	const struct got_error *err = NULL;
2207 
2208 	*new_te = calloc(1, sizeof(**new_te));
2209 	if (*new_te == NULL)
2210 		return got_error_from_errno("calloc");
2211 
2212 	(*new_te)->mode = te->mode;
2213 	memcpy((*new_te)->name, te->name, sizeof((*new_te)->name));
2214 	memcpy(&(*new_te)->id, &te->id, sizeof((*new_te)->id));
2215 	return err;
2216 }
2217 
2218 int
2219 got_object_tree_entry_is_submodule(struct got_tree_entry *te)
2220 {
2221 	return (te->mode & S_IFMT) == (S_IFDIR | S_IFLNK);
2222 }
2223 
2224 int
2225 got_object_tree_entry_is_symlink(struct got_tree_entry *te)
2226 {
2227 	/* S_IFDIR check avoids confusing symlinks with submodules. */
2228 	return ((te->mode & (S_IFDIR | S_IFLNK)) == S_IFLNK);
2229 }
2230 
2231 static const struct got_error *
2232 resolve_symlink(char **link_target, const char *path,
2233     struct got_commit_object *commit, struct got_repository *repo)
2234 {
2235 	const struct got_error *err = NULL;
2236 	char buf[PATH_MAX];
2237 	char *name, *parent_path = NULL;
2238 	struct got_object_id *tree_obj_id = NULL;
2239 	struct got_tree_object *tree = NULL;
2240 	struct got_tree_entry *te = NULL;
2241 
2242 	*link_target = NULL;
2243 
2244 	if (strlcpy(buf, path, sizeof(buf)) >= sizeof(buf))
2245 		return got_error(GOT_ERR_NO_SPACE);
2246 
2247 	name = basename(buf);
2248 	if (name == NULL)
2249 		return got_error_from_errno2("basename", path);
2250 
2251 	err = got_path_dirname(&parent_path, path);
2252 	if (err)
2253 		return err;
2254 
2255 	err = got_object_id_by_path(&tree_obj_id, repo, commit,
2256 	    parent_path);
2257 	if (err) {
2258 		if (err->code == GOT_ERR_NO_TREE_ENTRY) {
2259 			/* Display the complete path in error message. */
2260 			err = got_error_path(path, err->code);
2261 		}
2262 		goto done;
2263 	}
2264 
2265 	err = got_object_open_as_tree(&tree, repo, tree_obj_id);
2266 	if (err)
2267 		goto done;
2268 
2269 	te = got_object_tree_find_entry(tree, name);
2270 	if (te == NULL) {
2271 		err = got_error_path(path, GOT_ERR_NO_TREE_ENTRY);
2272 		goto done;
2273 	}
2274 
2275 	if (got_object_tree_entry_is_symlink(te)) {
2276 		err = got_tree_entry_get_symlink_target(link_target, te, repo);
2277 		if (err)
2278 			goto done;
2279 		if (!got_path_is_absolute(*link_target)) {
2280 			char *abspath;
2281 			if (asprintf(&abspath, "%s/%s", parent_path,
2282 			    *link_target) == -1) {
2283 				err = got_error_from_errno("asprintf");
2284 				goto done;
2285 			}
2286 			free(*link_target);
2287 			*link_target = malloc(PATH_MAX);
2288 			if (*link_target == NULL) {
2289 				err = got_error_from_errno("malloc");
2290 				goto done;
2291 			}
2292 			err = got_canonpath(abspath, *link_target, PATH_MAX);
2293 			free(abspath);
2294 			if (err)
2295 				goto done;
2296 		}
2297 	}
2298 done:
2299 	free(tree_obj_id);
2300 	if (tree)
2301 		got_object_tree_close(tree);
2302 	if (err) {
2303 		free(*link_target);
2304 		*link_target = NULL;
2305 	}
2306 	return err;
2307 }
2308 
2309 const struct got_error *
2310 got_object_resolve_symlinks(char **link_target, const char *path,
2311     struct got_commit_object *commit, struct got_repository *repo)
2312 {
2313 	const struct got_error *err = NULL;
2314 	char *next_target = NULL;
2315 	int max_recursion = 40; /* matches Git */
2316 
2317 	*link_target = NULL;
2318 
2319 	do {
2320 		err = resolve_symlink(&next_target,
2321 		    *link_target ? *link_target : path, commit, repo);
2322 		if (err)
2323 			break;
2324 		if (next_target) {
2325 			free(*link_target);
2326 			if (--max_recursion == 0) {
2327 				err = got_error_path(path, GOT_ERR_RECURSION);
2328 				*link_target = NULL;
2329 				break;
2330 			}
2331 			*link_target = next_target;
2332 		}
2333 	} while (next_target);
2334 
2335 	return err;
2336 }
2337 
2338 const struct got_error *
2339 got_traverse_packed_commits(struct got_object_id_queue *traversed_commits,
2340     struct got_object_id *commit_id, const char *path,
2341     struct got_repository *repo)
2342 {
2343 	const struct got_error *err = NULL;
2344 	struct got_pack *pack = NULL;
2345 	struct got_packidx *packidx = NULL;
2346 	char *path_packfile = NULL;
2347 	struct got_commit_object *changed_commit = NULL;
2348 	struct got_object_id *changed_commit_id = NULL;
2349 	int idx;
2350 
2351 	err = got_repo_search_packidx(&packidx, &idx, repo, commit_id);
2352 	if (err) {
2353 		if (err->code != GOT_ERR_NO_OBJ)
2354 			return err;
2355 		return NULL;
2356 	}
2357 
2358 	err = got_packidx_get_packfile_path(&path_packfile,
2359 	    packidx->path_packidx);
2360 	if (err)
2361 		return err;
2362 
2363 	pack = got_repo_get_cached_pack(repo, path_packfile);
2364 	if (pack == NULL) {
2365 		err = got_repo_cache_pack(&pack, repo, path_packfile, packidx);
2366 		if (err)
2367 			goto done;
2368 	}
2369 
2370 	if (pack->privsep_child == NULL) {
2371 		err = start_pack_privsep_child(pack, packidx);
2372 		if (err)
2373 			goto done;
2374 	}
2375 
2376 	err = got_privsep_send_commit_traversal_request(
2377 	    pack->privsep_child->ibuf, commit_id, idx, path);
2378 	if (err)
2379 		goto done;
2380 
2381 	err = got_privsep_recv_traversed_commits(&changed_commit,
2382 	    &changed_commit_id, traversed_commits, pack->privsep_child->ibuf);
2383 	if (err)
2384 		goto done;
2385 
2386 	if (changed_commit) {
2387 		/*
2388 		 * Cache the commit in which the path was changed.
2389 		 * This commit might be opened again soon.
2390 		 */
2391 		changed_commit->refcnt++;
2392 		err = got_repo_cache_commit(repo, changed_commit_id,
2393 		    changed_commit);
2394 		got_object_commit_close(changed_commit);
2395 	}
2396 done:
2397 	free(path_packfile);
2398 	free(changed_commit_id);
2399 	return err;
2400 }
2401 
2402 const struct got_error *
2403 got_object_enumerate(int *found_all_objects,
2404     got_object_enumerate_commit_cb cb_commit,
2405     got_object_enumerate_tree_cb cb_tree, void *cb_arg,
2406     struct got_object_id **ours, int nours,
2407     struct got_object_id **theirs, int ntheirs,
2408     struct got_packidx *packidx, struct got_repository *repo)
2409 {
2410 	const struct got_error *err = NULL;
2411 	struct got_pack *pack;
2412 	char *path_packfile = NULL;
2413 
2414 	err = got_packidx_get_packfile_path(&path_packfile,
2415 	    packidx->path_packidx);
2416 	if (err)
2417 		return err;
2418 
2419 	pack = got_repo_get_cached_pack(repo, path_packfile);
2420 	if (pack == NULL) {
2421 		err = got_repo_cache_pack(&pack, repo, path_packfile, packidx);
2422 		if (err)
2423 			goto done;
2424 	}
2425 
2426 	if (pack->privsep_child == NULL) {
2427 		err = start_pack_privsep_child(pack, packidx);
2428 		if (err)
2429 			goto done;
2430 	}
2431 
2432 	err = got_privsep_send_object_enumeration_request(
2433 	    pack->privsep_child->ibuf);
2434 	if (err)
2435 		goto done;
2436 
2437 	err = got_privsep_send_object_idlist(pack->privsep_child->ibuf,
2438 	    ours, nours);
2439 	if (err)
2440 		goto done;
2441 	err = got_privsep_send_object_idlist_done(pack->privsep_child->ibuf);
2442 	if (err)
2443 		goto done;
2444 
2445 	err = got_privsep_send_object_idlist(pack->privsep_child->ibuf,
2446 	    theirs, ntheirs);
2447 	if (err)
2448 		goto done;
2449 	err = got_privsep_send_object_idlist_done(pack->privsep_child->ibuf);
2450 	if (err)
2451 		goto done;
2452 
2453 	err = got_privsep_recv_enumerated_objects(found_all_objects,
2454 	    pack->privsep_child->ibuf, cb_commit, cb_tree, cb_arg, repo);
2455 done:
2456 	free(path_packfile);
2457 	return err;
2458 }