Got Mirror

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Date:: Thu Jul 23 14:21:27 2020 UTC
Message:: let 'got checkout' create symlinks in a work tree
Actions:: History | Blame | Raw File
1 /*
2  * Copyright (c) 2018, 2019 Stefan Sperling <stsp@openbsd.org>
3  *
4  * Permission to use, copy, modify, and distribute this software for any
5  * purpose with or without fee is hereby granted, provided that the above
6  * copyright notice and this permission notice appear in all copies.
7  *
8  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
9  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
10  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
11  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
12  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
13  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
14  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
15  */
16 
17 #include <sys/types.h>
18 #include <sys/stat.h>
19 #include <sys/queue.h>
20 #include <sys/uio.h>
21 #include <sys/socket.h>
22 #include <sys/wait.h>
23 #include <sys/syslimits.h>
24 #include <sys/resource.h>
25 
26 #include <errno.h>
27 #include <fcntl.h>
28 #include <stdio.h>
29 #include <stdlib.h>
30 #include <string.h>
31 #include <stdint.h>
32 #include <sha1.h>
33 #include <zlib.h>
34 #include <ctype.h>
35 #include <limits.h>
36 #include <imsg.h>
37 #include <time.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 struct got_object_id *
61 got_object_get_id(struct got_object *obj)
62 {
63 	return &obj->id;
64 }
65 
66 const struct got_error *
67 got_object_get_id_str(char **outbuf, struct got_object *obj)
68 {
69 	return got_object_id_str(outbuf, &obj->id);
70 }
71 
72 const struct got_error *
73 got_object_get_type(int *type, struct got_repository *repo,
74     struct got_object_id *id)
75 {
76 	const struct got_error *err = NULL;
77 	struct got_object *obj;
78 
79 	err = got_object_open(&obj, repo, id);
80 	if (err)
81 		return err;
82 
83 	switch (obj->type) {
84 	case GOT_OBJ_TYPE_COMMIT:
85 	case GOT_OBJ_TYPE_TREE:
86 	case GOT_OBJ_TYPE_BLOB:
87 	case GOT_OBJ_TYPE_TAG:
88 		*type = obj->type;
89 		break;
90 	default:
91 		err = got_error(GOT_ERR_OBJ_TYPE);
92 		break;
93 	}
94 
95 	got_object_close(obj);
96 	return err;
97 }
98 
99 const struct got_error *
100 got_object_get_path(char **path, struct got_object_id *id,
101     struct got_repository *repo)
102 {
103 	const struct got_error *err = NULL;
104 	char *hex = NULL;
105 	char *path_objects;
106 
107 	*path = NULL;
108 
109 	path_objects = got_repo_get_path_objects(repo);
110 	if (path_objects == NULL)
111 		return got_error_from_errno("got_repo_get_path_objects");
112 
113 	err = got_object_id_str(&hex, id);
114 	if (err)
115 		goto done;
116 
117 	if (asprintf(path, "%s/%.2x/%s", path_objects,
118 	    id->sha1[0], hex + 2) == -1)
119 		err = got_error_from_errno("asprintf");
120 
121 done:
122 	free(hex);
123 	free(path_objects);
124 	return err;
125 }
126 
127 static const struct got_error *
128 open_loose_object(int *fd, struct got_object_id *id,
129     struct got_repository *repo)
130 {
131 	const struct got_error *err = NULL;
132 	char *path;
133 
134 	err = got_object_get_path(&path, id, repo);
135 	if (err)
136 		return err;
137 	*fd = open(path, O_RDONLY | O_NOFOLLOW);
138 	if (*fd == -1) {
139 		err = got_error_from_errno2("open", path);
140 		goto done;
141 	}
142 done:
143 	free(path);
144 	return err;
145 }
146 
147 static const struct got_error *
148 get_packfile_path(char **path_packfile, struct got_packidx *packidx)
149 {
150 	size_t size;
151 
152 	/* Packfile path contains ".pack" instead of ".idx", so add one byte. */
153 	size = strlen(packidx->path_packidx) + 2;
154 	if (size < GOT_PACKFILE_NAMELEN + 1)
155 		return got_error_path(packidx->path_packidx, GOT_ERR_BAD_PATH);
156 
157 	*path_packfile = malloc(size);
158 	if (*path_packfile == NULL)
159 		return got_error_from_errno("malloc");
160 
161 	/* Copy up to and excluding ".idx". */
162 	if (strlcpy(*path_packfile, packidx->path_packidx,
163 	    size - strlen(GOT_PACKIDX_SUFFIX) - 1) >= size)
164 		return got_error(GOT_ERR_NO_SPACE);
165 
166 	if (strlcat(*path_packfile, GOT_PACKFILE_SUFFIX, size) >= size)
167 		return got_error(GOT_ERR_NO_SPACE);
168 
169 	return NULL;
170 }
171 
172 static const struct got_error *
173 request_packed_object(struct got_object **obj, struct got_pack *pack, int idx,
174     struct got_object_id *id)
175 {
176 	const struct got_error *err = NULL;
177 	struct imsgbuf *ibuf = pack->privsep_child->ibuf;
178 
179 	err = got_privsep_send_packed_obj_req(ibuf, idx, id);
180 	if (err)
181 		return err;
182 
183 	err = got_privsep_recv_obj(obj, ibuf);
184 	if (err)
185 		return err;
186 
187 	memcpy(&(*obj)->id, id, sizeof((*obj)->id));
188 
189 	return NULL;
190 }
191 
192 static void
193 set_max_datasize(void)
194 {
195 	struct rlimit rl;
196 
197 	if (getrlimit(RLIMIT_DATA, &rl) != 0)
198 		return;
199 
200 	rl.rlim_cur = rl.rlim_max;
201 	setrlimit(RLIMIT_DATA, &rl);
202 }
203 
204 static const struct got_error *
205 start_pack_privsep_child(struct got_pack *pack, struct got_packidx *packidx)
206 {
207 	const struct got_error *err = NULL;
208 	int imsg_fds[2];
209 	pid_t pid;
210 	struct imsgbuf *ibuf;
211 
212 	ibuf = calloc(1, sizeof(*ibuf));
213 	if (ibuf == NULL)
214 		return got_error_from_errno("calloc");
215 
216 	pack->privsep_child = calloc(1, sizeof(*pack->privsep_child));
217 	if (pack->privsep_child == NULL) {
218 		err = got_error_from_errno("calloc");
219 		free(ibuf);
220 		return err;
221 	}
222 
223 	if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, imsg_fds) == -1) {
224 		err = got_error_from_errno("socketpair");
225 		goto done;
226 	}
227 
228 	pid = fork();
229 	if (pid == -1) {
230 		err = got_error_from_errno("fork");
231 		goto done;
232 	} else if (pid == 0) {
233 		set_max_datasize();
234 		got_privsep_exec_child(imsg_fds, GOT_PATH_PROG_READ_PACK,
235 		    pack->path_packfile);
236 		/* not reached */
237 	}
238 
239 	if (close(imsg_fds[1]) != 0)
240 		return got_error_from_errno("close");
241 	pack->privsep_child->imsg_fd = imsg_fds[0];
242 	pack->privsep_child->pid = pid;
243 	imsg_init(ibuf, imsg_fds[0]);
244 	pack->privsep_child->ibuf = ibuf;
245 
246 	err = got_privsep_init_pack_child(ibuf, pack, packidx);
247 	if (err) {
248 		const struct got_error *child_err;
249 		err = got_privsep_send_stop(pack->privsep_child->imsg_fd);
250 		child_err = got_privsep_wait_for_child(
251 		    pack->privsep_child->pid);
252 		if (child_err && err == NULL)
253 			err = child_err;
254 	}
255 done:
256 	if (err) {
257 		free(ibuf);
258 		free(pack->privsep_child);
259 		pack->privsep_child = NULL;
260 	}
261 	return err;
262 }
263 
264 static const struct got_error *
265 read_packed_object_privsep(struct got_object **obj,
266     struct got_repository *repo, struct got_pack *pack,
267     struct got_packidx *packidx, int idx, struct got_object_id *id)
268 {
269 	const struct got_error *err = NULL;
270 
271 	if (pack->privsep_child)
272 		return request_packed_object(obj, pack, idx, id);
273 
274 	err = start_pack_privsep_child(pack, packidx);
275 	if (err)
276 		return err;
277 
278 	return request_packed_object(obj, pack, idx, id);
279 }
280 
281 
282 static const struct got_error *
283 open_packed_object(struct got_object **obj, struct got_object_id *id,
284     struct got_repository *repo)
285 {
286 	const struct got_error *err = NULL;
287 	struct got_pack *pack = NULL;
288 	struct got_packidx *packidx = NULL;
289 	int idx;
290 	char *path_packfile;
291 
292 	err = got_repo_search_packidx(&packidx, &idx, repo, id);
293 	if (err)
294 		return err;
295 
296 	err = get_packfile_path(&path_packfile, packidx);
297 	if (err)
298 		return err;
299 
300 	pack = got_repo_get_cached_pack(repo, path_packfile);
301 	if (pack == NULL) {
302 		err = got_repo_cache_pack(&pack, repo, path_packfile, packidx);
303 		if (err)
304 			goto done;
305 	}
306 
307 	err = read_packed_object_privsep(obj, repo, pack, packidx, idx, id);
308 	if (err)
309 		goto done;
310 done:
311 	free(path_packfile);
312 	return err;
313 }
314 
315 static const struct got_error *
316 request_object(struct got_object **obj, struct got_repository *repo, int fd)
317 {
318 	const struct got_error *err = NULL;
319 	struct imsgbuf *ibuf;
320 
321 	ibuf = repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_OBJECT].ibuf;
322 
323 	err = got_privsep_send_obj_req(ibuf, fd);
324 	if (err)
325 		return err;
326 
327 	return got_privsep_recv_obj(obj, ibuf);
328 }
329 
330 static const struct got_error *
331 read_object_header_privsep(struct got_object **obj, struct got_repository *repo,
332     int obj_fd)
333 {
334 	const struct got_error *err;
335 	int imsg_fds[2];
336 	pid_t pid;
337 	struct imsgbuf *ibuf;
338 
339 	if (repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_OBJECT].imsg_fd != -1)
340 		return request_object(obj, repo, obj_fd);
341 
342 	ibuf = calloc(1, sizeof(*ibuf));
343 	if (ibuf == NULL)
344 		return got_error_from_errno("calloc");
345 
346 	if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, imsg_fds) == -1) {
347 		err = got_error_from_errno("socketpair");
348 		free(ibuf);
349 		return err;
350 	}
351 
352 	pid = fork();
353 	if (pid == -1) {
354 		err = got_error_from_errno("fork");
355 		free(ibuf);
356 		return err;
357 	}
358 	else if (pid == 0) {
359 		got_privsep_exec_child(imsg_fds, GOT_PATH_PROG_READ_OBJECT,
360 		    repo->path);
361 		/* not reached */
362 	}
363 
364 	if (close(imsg_fds[1]) != 0) {
365 		err = got_error_from_errno("close");
366 		free(ibuf);
367 		return err;
368 	}
369 	repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_OBJECT].imsg_fd =
370 	    imsg_fds[0];
371 	repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_OBJECT].pid = pid;
372 	imsg_init(ibuf, imsg_fds[0]);
373 	repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_OBJECT].ibuf = ibuf;
374 
375 	return request_object(obj, repo, obj_fd);
376 }
377 
378 
379 const struct got_error *
380 got_object_open(struct got_object **obj, struct got_repository *repo,
381     struct got_object_id *id)
382 {
383 	const struct got_error *err = NULL;
384 	char *path;
385 	int fd;
386 
387 	*obj = got_repo_get_cached_object(repo, id);
388 	if (*obj != NULL) {
389 		(*obj)->refcnt++;
390 		return NULL;
391 	}
392 
393 	err = open_packed_object(obj, id, repo);
394 	if (err && err->code != GOT_ERR_NO_OBJ)
395 		return err;
396 	if (*obj) {
397 		(*obj)->refcnt++;
398 		return got_repo_cache_object(repo, id, *obj);
399 	}
400 
401 	err = got_object_get_path(&path, id, repo);
402 	if (err)
403 		return err;
404 
405 	fd = open(path, O_RDONLY | O_NOFOLLOW);
406 	if (fd == -1) {
407 		if (errno == ENOENT)
408 			err = got_error_no_obj(id);
409 		else
410 			err = got_error_from_errno2("open", path);
411 		goto done;
412 	} else {
413 		err = read_object_header_privsep(obj, repo, fd);
414 		if (err)
415 			goto done;
416 		memcpy((*obj)->id.sha1, id->sha1, SHA1_DIGEST_LENGTH);
417 	}
418 
419 	(*obj)->refcnt++;
420 	err = got_repo_cache_object(repo, id, *obj);
421 done:
422 	free(path);
423 	return err;
424 
425 }
426 
427 const struct got_error *
428 got_object_open_by_id_str(struct got_object **obj, struct got_repository *repo,
429     const char *id_str)
430 {
431 	struct got_object_id id;
432 
433 	if (!got_parse_sha1_digest(id.sha1, id_str))
434 		return got_error_path(id_str, GOT_ERR_BAD_OBJ_ID_STR);
435 
436 	return got_object_open(obj, repo, &id);
437 }
438 
439 const struct got_error *
440 got_object_resolve_id_str(struct got_object_id **id,
441     struct got_repository *repo, const char *id_str)
442 {
443 	const struct got_error *err = NULL;
444 	struct got_object *obj;
445 
446 	err = got_object_open_by_id_str(&obj, repo, id_str);
447 	if (err)
448 		return err;
449 
450 	*id = got_object_id_dup(got_object_get_id(obj));
451 	got_object_close(obj);
452 	if (*id == NULL)
453 		return got_error_from_errno("got_object_id_dup");
454 
455 	return NULL;
456 }
457 
458 static const struct got_error *
459 request_packed_commit(struct got_commit_object **commit, struct got_pack *pack,
460     int pack_idx, struct got_object_id *id)
461 {
462 	const struct got_error *err = NULL;
463 
464 	err = got_privsep_send_commit_req(pack->privsep_child->ibuf, -1, id,
465 	    pack_idx);
466 	if (err)
467 		return err;
468 
469 	err = got_privsep_recv_commit(commit, pack->privsep_child->ibuf);
470 	if (err)
471 		return err;
472 
473 	(*commit)->flags |= GOT_COMMIT_FLAG_PACKED;
474 	return NULL;
475 }
476 
477 static const struct got_error *
478 read_packed_commit_privsep(struct got_commit_object **commit,
479     struct got_pack *pack, struct got_packidx *packidx, int idx,
480     struct got_object_id *id)
481 {
482 	const struct got_error *err = NULL;
483 
484 	if (pack->privsep_child)
485 		return request_packed_commit(commit, pack, idx, id);
486 
487 	err = start_pack_privsep_child(pack, packidx);
488 	if (err)
489 		return err;
490 
491 	return request_packed_commit(commit, pack, idx, id);
492 }
493 
494 static const struct got_error *
495 request_commit(struct got_commit_object **commit, struct got_repository *repo,
496     int fd)
497 {
498 	const struct got_error *err = NULL;
499 	struct imsgbuf *ibuf;
500 
501 	ibuf = repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_COMMIT].ibuf;
502 
503 	err = got_privsep_send_commit_req(ibuf, fd, NULL, -1);
504 	if (err)
505 		return err;
506 
507 	return got_privsep_recv_commit(commit, ibuf);
508 }
509 
510 static const struct got_error *
511 read_commit_privsep(struct got_commit_object **commit, int obj_fd,
512     struct got_repository *repo)
513 {
514 	const struct got_error *err;
515 	int imsg_fds[2];
516 	pid_t pid;
517 	struct imsgbuf *ibuf;
518 
519 	if (repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_COMMIT].imsg_fd != -1)
520 		return request_commit(commit, repo, obj_fd);
521 
522 	ibuf = calloc(1, sizeof(*ibuf));
523 	if (ibuf == NULL)
524 		return got_error_from_errno("calloc");
525 
526 	if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, imsg_fds) == -1) {
527 		err = got_error_from_errno("socketpair");
528 		free(ibuf);
529 		return err;
530 	}
531 
532 	pid = fork();
533 	if (pid == -1) {
534 		err = got_error_from_errno("fork");
535 		free(ibuf);
536 		return err;
537 	}
538 	else if (pid == 0) {
539 		got_privsep_exec_child(imsg_fds, GOT_PATH_PROG_READ_COMMIT,
540 		    repo->path);
541 		/* not reached */
542 	}
543 
544 	if (close(imsg_fds[1]) != 0) {
545 		err = got_error_from_errno("close");
546 		free(ibuf);
547 		return err;
548 	}
549 	repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_COMMIT].imsg_fd =
550 	    imsg_fds[0];
551 	repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_COMMIT].pid = pid;
552 	imsg_init(ibuf, imsg_fds[0]);
553 	repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_COMMIT].ibuf = ibuf;
554 
555 	return request_commit(commit, repo, obj_fd);
556 }
557 
558 
559 static const struct got_error *
560 open_commit(struct got_commit_object **commit,
561     struct got_repository *repo, struct got_object_id *id, int check_cache)
562 {
563 	const struct got_error *err = NULL;
564 	struct got_packidx *packidx = NULL;
565 	int idx;
566 	char *path_packfile = NULL;
567 
568 	if (check_cache) {
569 		*commit = got_repo_get_cached_commit(repo, id);
570 		if (*commit != NULL) {
571 			(*commit)->refcnt++;
572 			return NULL;
573 		}
574 	} else
575 		*commit = NULL;
576 
577 	err = got_repo_search_packidx(&packidx, &idx, repo, id);
578 	if (err == NULL) {
579 		struct got_pack *pack = NULL;
580 
581 		err = get_packfile_path(&path_packfile, packidx);
582 		if (err)
583 			return err;
584 
585 		pack = got_repo_get_cached_pack(repo, path_packfile);
586 		if (pack == NULL) {
587 			err = got_repo_cache_pack(&pack, repo, path_packfile,
588 			    packidx);
589 			if (err)
590 				goto done;
591 		}
592 		err = read_packed_commit_privsep(commit, pack,
593 		    packidx, idx, id);
594 	} else if (err->code == GOT_ERR_NO_OBJ) {
595 		int fd;
596 
597 		err = open_loose_object(&fd, id, repo);
598 		if (err)
599 			return err;
600 		err = read_commit_privsep(commit, fd, repo);
601 	}
602 
603 	if (err == NULL) {
604 		(*commit)->refcnt++;
605 		err = got_repo_cache_commit(repo, id, *commit);
606 	}
607 done:
608 	free(path_packfile);
609 	return err;
610 }
611 
612 const struct got_error *
613 got_object_open_as_commit(struct got_commit_object **commit,
614     struct got_repository *repo, struct got_object_id *id)
615 {
616 	*commit = got_repo_get_cached_commit(repo, id);
617 	if (*commit != NULL) {
618 		(*commit)->refcnt++;
619 		return NULL;
620 	}
621 
622 	return open_commit(commit, repo, id, 0);
623 }
624 
625 const struct got_error *
626 got_object_commit_open(struct got_commit_object **commit,
627     struct got_repository *repo, struct got_object *obj)
628 {
629 	return open_commit(commit, repo, got_object_get_id(obj), 1);
630 }
631 
632 const struct got_error *
633 got_object_qid_alloc(struct got_object_qid **qid, struct got_object_id *id)
634 {
635 	const struct got_error *err = NULL;
636 
637 	*qid = calloc(1, sizeof(**qid));
638 	if (*qid == NULL)
639 		return got_error_from_errno("calloc");
640 
641 	(*qid)->id = got_object_id_dup(id);
642 	if ((*qid)->id == NULL) {
643 		err = got_error_from_errno("got_object_id_dup");
644 		got_object_qid_free(*qid);
645 		*qid = NULL;
646 		return err;
647 	}
648 
649 	return NULL;
650 }
651 
652 static const struct got_error *
653 request_packed_tree(struct got_tree_object **tree, struct got_pack *pack,
654     int pack_idx, struct got_object_id *id)
655 {
656 	const struct got_error *err = NULL;
657 
658 	err = got_privsep_send_tree_req(pack->privsep_child->ibuf, -1, id,
659 	    pack_idx);
660 	if (err)
661 		return err;
662 
663 	return got_privsep_recv_tree(tree, pack->privsep_child->ibuf);
664 }
665 
666 static const struct got_error *
667 read_packed_tree_privsep(struct got_tree_object **tree,
668     struct got_pack *pack, struct got_packidx *packidx, int idx,
669     struct got_object_id *id)
670 {
671 	const struct got_error *err = NULL;
672 
673 	if (pack->privsep_child)
674 		return request_packed_tree(tree, pack, idx, id);
675 
676 	err = start_pack_privsep_child(pack, packidx);
677 	if (err)
678 		return err;
679 
680 	return request_packed_tree(tree, pack, idx, id);
681 }
682 
683 static const struct got_error *
684 request_tree(struct got_tree_object **tree, struct got_repository *repo,
685     int fd)
686 {
687 	const struct got_error *err = NULL;
688 	struct imsgbuf *ibuf;
689 
690 	ibuf = repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_TREE].ibuf;
691 
692 	err = got_privsep_send_tree_req(ibuf, fd, NULL, -1);
693 	if (err)
694 		return err;
695 
696 	return got_privsep_recv_tree(tree, ibuf);
697 }
698 
699 const struct got_error *
700 read_tree_privsep(struct got_tree_object **tree, int obj_fd,
701     struct got_repository *repo)
702 {
703 	const struct got_error *err;
704 	int imsg_fds[2];
705 	pid_t pid;
706 	struct imsgbuf *ibuf;
707 
708 	if (repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_TREE].imsg_fd != -1)
709 		return request_tree(tree, repo, obj_fd);
710 
711 	ibuf = calloc(1, sizeof(*ibuf));
712 	if (ibuf == NULL)
713 		return got_error_from_errno("calloc");
714 
715 	if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, imsg_fds) == -1) {
716 		err = got_error_from_errno("socketpair");
717 		free(ibuf);
718 		return err;
719 	}
720 
721 	pid = fork();
722 	if (pid == -1) {
723 		err = got_error_from_errno("fork");
724 		free(ibuf);
725 		return err;
726 	}
727 	else if (pid == 0) {
728 		got_privsep_exec_child(imsg_fds, GOT_PATH_PROG_READ_TREE,
729 		    repo->path);
730 		/* not reached */
731 	}
732 
733 	if (close(imsg_fds[1]) != 0) {
734 		err = got_error_from_errno("close");
735 		free(ibuf);
736 		return err;
737 	}
738 	repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_TREE].imsg_fd =
739 	    imsg_fds[0];
740 	repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_TREE].pid = pid;
741 	imsg_init(ibuf, imsg_fds[0]);
742 	repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_TREE].ibuf = ibuf;
743 
744 
745 	return request_tree(tree, repo, obj_fd);
746 }
747 
748 static const struct got_error *
749 open_tree(struct got_tree_object **tree, struct got_repository *repo,
750     struct got_object_id *id, int check_cache)
751 {
752 	const struct got_error *err = NULL;
753 	struct got_packidx *packidx = NULL;
754 	int idx;
755 	char *path_packfile = NULL;
756 
757 	if (check_cache) {
758 		*tree = got_repo_get_cached_tree(repo, id);
759 		if (*tree != NULL) {
760 			(*tree)->refcnt++;
761 			return NULL;
762 		}
763 	} else
764 		*tree = NULL;
765 
766 	err = got_repo_search_packidx(&packidx, &idx, repo, id);
767 	if (err == NULL) {
768 		struct got_pack *pack = NULL;
769 
770 		err = get_packfile_path(&path_packfile, packidx);
771 		if (err)
772 			return err;
773 
774 		pack = got_repo_get_cached_pack(repo, path_packfile);
775 		if (pack == NULL) {
776 			err = got_repo_cache_pack(&pack, repo, path_packfile,
777 			    packidx);
778 			if (err)
779 				goto done;
780 		}
781 		err = read_packed_tree_privsep(tree, pack,
782 		    packidx, idx, id);
783 	} else if (err->code == GOT_ERR_NO_OBJ) {
784 		int fd;
785 
786 		err = open_loose_object(&fd, id, repo);
787 		if (err)
788 			return err;
789 		err = read_tree_privsep(tree, fd, repo);
790 	}
791 
792 	if (err == NULL) {
793 		(*tree)->refcnt++;
794 		err = got_repo_cache_tree(repo, id, *tree);
795 	}
796 done:
797 	free(path_packfile);
798 	return err;
799 }
800 
801 const struct got_error *
802 got_object_open_as_tree(struct got_tree_object **tree,
803     struct got_repository *repo, struct got_object_id *id)
804 {
805 	*tree = got_repo_get_cached_tree(repo, id);
806 	if (*tree != NULL) {
807 		(*tree)->refcnt++;
808 		return NULL;
809 	}
810 
811 	return open_tree(tree, repo, id, 0);
812 }
813 
814 const struct got_error *
815 got_object_tree_open(struct got_tree_object **tree,
816     struct got_repository *repo, struct got_object *obj)
817 {
818 	return open_tree(tree, repo, got_object_get_id(obj), 1);
819 }
820 
821 int
822 got_object_tree_get_nentries(struct got_tree_object *tree)
823 {
824 	return tree->nentries;
825 }
826 
827 struct got_tree_entry *
828 got_object_tree_get_first_entry(struct got_tree_object *tree)
829 {
830 	return got_object_tree_get_entry(tree, 0);
831 }
832 
833 struct got_tree_entry *
834 got_object_tree_get_last_entry(struct got_tree_object *tree)
835 {
836 	return got_object_tree_get_entry(tree, tree->nentries - 1);
837 }
838 
839 struct got_tree_entry *
840 got_object_tree_get_entry(struct got_tree_object *tree, int i)
841 {
842 	if (i < 0 || i >= tree->nentries)
843 		return NULL;
844 	return &tree->entries[i];
845 }
846 
847 mode_t
848 got_tree_entry_get_mode(struct got_tree_entry *te)
849 {
850 	return te->mode;
851 }
852 
853 const char *
854 got_tree_entry_get_name(struct got_tree_entry *te)
855 {
856 	return &te->name[0];
857 }
858 
859 struct got_object_id *
860 got_tree_entry_get_id(struct got_tree_entry *te)
861 {
862 	return &te->id;
863 }
864 
865 const struct got_error *
866 got_tree_entry_get_symlink_target(char **link_target, struct got_tree_entry *te,
867     struct got_repository *repo)
868 {
869 	const struct got_error *err = NULL;
870 	struct got_blob_object *blob = NULL;
871 	size_t len;
872 
873 	*link_target = NULL;
874 
875 	/* S_IFDIR check avoids confusing symlinks with submodules. */
876 	if ((te->mode & (S_IFDIR | S_IFLNK)) != S_IFLNK)
877 		return got_error(GOT_ERR_TREE_ENTRY_TYPE);
878 
879 	err = got_object_open_as_blob(&blob, repo,
880 	    got_tree_entry_get_id(te), PATH_MAX);
881 	if (err)
882 		return err;
883 	
884 	err = got_object_blob_read_block(&len, blob);
885 	if (err)
886 		goto done;
887 
888 	*link_target = malloc(len + 1);
889 	if (*link_target == NULL) {
890 		err = got_error_from_errno("malloc");
891 		goto done;
892 	}
893 	memcpy(*link_target, got_object_blob_get_read_buf(blob), len);
894 	(*link_target)[len] = '\0';
895 done:
896 	if (blob)
897 		got_object_blob_close(blob);
898 	return err;
899 }
900 
901 int
902 got_tree_entry_get_index(struct got_tree_entry *te)
903 {
904 	return te->idx;
905 }
906 
907 struct got_tree_entry *
908 got_tree_entry_get_next(struct got_tree_object *tree,
909     struct got_tree_entry *te)
910 {
911 	return got_object_tree_get_entry(tree, te->idx + 1);
912 }
913 
914 struct got_tree_entry *
915 got_tree_entry_get_prev(struct got_tree_object *tree,
916     struct got_tree_entry *te)
917 {
918 	return got_object_tree_get_entry(tree, te->idx - 1);
919 }
920 
921 static const struct got_error *
922 request_packed_blob(uint8_t **outbuf, size_t *size, size_t *hdrlen, int outfd,
923     struct got_pack *pack, struct got_packidx *packidx, int idx,
924     struct got_object_id *id)
925 {
926 	const struct got_error *err = NULL;
927 	int outfd_child;
928 	int basefd, accumfd; /* temporary files for delta application */
929 
930 	basefd = got_opentempfd();
931 	if (basefd == -1)
932 		return got_error_from_errno("got_opentempfd");
933 	accumfd = got_opentempfd();
934 	if (accumfd == -1)
935 		return got_error_from_errno("got_opentempfd");
936 
937 	outfd_child = dup(outfd);
938 	if (outfd_child == -1)
939 		return got_error_from_errno("dup");
940 
941 	err = got_privsep_send_blob_req(pack->privsep_child->ibuf, -1, id, idx);
942 	if (err)
943 		return err;
944 
945 	err = got_privsep_send_blob_outfd(pack->privsep_child->ibuf,
946 	    outfd_child);
947 	if (err) {
948 		close(basefd);
949 		close(accumfd);
950 		return err;
951 	}
952 
953 	err = got_privsep_send_tmpfd(pack->privsep_child->ibuf,
954 	    basefd);
955 	if (err) {
956 		close(accumfd);
957 		return err;
958 	}
959 
960 	err = got_privsep_send_tmpfd(pack->privsep_child->ibuf,
961 	    accumfd);
962 	if (err)
963 		return err;
964 
965 	err = got_privsep_recv_blob(outbuf, size, hdrlen,
966 	    pack->privsep_child->ibuf);
967 	if (err)
968 		return err;
969 
970 	if (lseek(outfd, SEEK_SET, 0) == -1)
971 		err = got_error_from_errno("lseek");
972 
973 	return err;
974 }
975 
976 static const struct got_error *
977 read_packed_blob_privsep(uint8_t **outbuf, size_t *size, size_t *hdrlen,
978     int outfd, struct got_pack *pack, struct got_packidx *packidx, int idx,
979     struct got_object_id *id)
980 {
981 	const struct got_error *err = NULL;
982 
983 	if (pack->privsep_child == NULL) {
984 		err = start_pack_privsep_child(pack, packidx);
985 		if (err)
986 			return err;
987 	}
988 
989 	return request_packed_blob(outbuf, size, hdrlen, outfd, pack, packidx,
990 	    idx, id);
991 }
992 
993 static const struct got_error *
994 request_blob(uint8_t **outbuf, size_t *size, size_t *hdrlen, int outfd,
995     int infd, struct imsgbuf *ibuf)
996 {
997 	const struct got_error *err = NULL;
998 	int outfd_child;
999 
1000 	outfd_child = dup(outfd);
1001 	if (outfd_child == -1)
1002 		return got_error_from_errno("dup");
1003 
1004 	err = got_privsep_send_blob_req(ibuf, infd, NULL, -1);
1005 	if (err)
1006 		return err;
1007 
1008 	err = got_privsep_send_blob_outfd(ibuf, outfd_child);
1009 	if (err)
1010 		return err;
1011 
1012 	err = got_privsep_recv_blob(outbuf, size, hdrlen, ibuf);
1013 	if (err)
1014 		return err;
1015 
1016 	if (lseek(outfd, SEEK_SET, 0) == -1)
1017 		return got_error_from_errno("lseek");
1018 
1019 	return err;
1020 }
1021 
1022 static const struct got_error *
1023 read_blob_privsep(uint8_t **outbuf, size_t *size, size_t *hdrlen,
1024     int outfd, int infd, struct got_repository *repo)
1025 {
1026 	const struct got_error *err;
1027 	int imsg_fds[2];
1028 	pid_t pid;
1029 	struct imsgbuf *ibuf;
1030 
1031 	if (repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_BLOB].imsg_fd != -1) {
1032 		ibuf = repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_BLOB].ibuf;
1033 		return request_blob(outbuf, size, hdrlen, outfd, infd, ibuf);
1034 	}
1035 
1036 	ibuf = calloc(1, sizeof(*ibuf));
1037 	if (ibuf == NULL)
1038 		return got_error_from_errno("calloc");
1039 
1040 	if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, imsg_fds) == -1) {
1041 		err = got_error_from_errno("socketpair");
1042 		free(ibuf);
1043 		return err;
1044 	}
1045 
1046 	pid = fork();
1047 	if (pid == -1) {
1048 		err = got_error_from_errno("fork");
1049 		free(ibuf);
1050 		return err;
1051 	}
1052 	else if (pid == 0) {
1053 		got_privsep_exec_child(imsg_fds, GOT_PATH_PROG_READ_BLOB,
1054 		    repo->path);
1055 		/* not reached */
1056 	}
1057 
1058 	if (close(imsg_fds[1]) != 0) {
1059 		err = got_error_from_errno("close");
1060 		free(ibuf);
1061 		return err;
1062 	}
1063 	repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_BLOB].imsg_fd =
1064 	    imsg_fds[0];
1065 	repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_BLOB].pid = pid;
1066 	imsg_init(ibuf, imsg_fds[0]);
1067 	repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_BLOB].ibuf = ibuf;
1068 
1069 	return request_blob(outbuf, size, hdrlen, outfd, infd, ibuf);
1070 }
1071 
1072 static const struct got_error *
1073 open_blob(struct got_blob_object **blob, struct got_repository *repo,
1074     struct got_object_id *id, size_t blocksize)
1075 {
1076 	const struct got_error *err = NULL;
1077 	struct got_packidx *packidx = NULL;
1078 	int idx;
1079 	char *path_packfile = NULL;
1080 	uint8_t *outbuf;
1081 	int outfd;
1082 	size_t size, hdrlen;
1083 	struct stat sb;
1084 
1085 	*blob = calloc(1, sizeof(**blob));
1086 	if (*blob == NULL)
1087 		return got_error_from_errno("calloc");
1088 
1089 	outfd = got_opentempfd();
1090 	if (outfd == -1)
1091 		return got_error_from_errno("got_opentempfd");
1092 
1093 	(*blob)->read_buf = malloc(blocksize);
1094 	if ((*blob)->read_buf == NULL) {
1095 		err = got_error_from_errno("malloc");
1096 		goto done;
1097 	}
1098 
1099 	err = got_repo_search_packidx(&packidx, &idx, repo, id);
1100 	if (err == NULL) {
1101 		struct got_pack *pack = NULL;
1102 
1103 		err = get_packfile_path(&path_packfile, packidx);
1104 		if (err)
1105 			goto done;
1106 
1107 		pack = got_repo_get_cached_pack(repo, path_packfile);
1108 		if (pack == NULL) {
1109 			err = got_repo_cache_pack(&pack, repo, path_packfile,
1110 			    packidx);
1111 			if (err)
1112 				goto done;
1113 		}
1114 		err = read_packed_blob_privsep(&outbuf, &size, &hdrlen, outfd,
1115 		    pack, packidx, idx, id);
1116 	} else if (err->code == GOT_ERR_NO_OBJ) {
1117 		int infd;
1118 
1119 		err = open_loose_object(&infd, id, repo);
1120 		if (err)
1121 			goto done;
1122 		err = read_blob_privsep(&outbuf, &size, &hdrlen, outfd, infd,
1123 		    repo);
1124 	}
1125 	if (err)
1126 		goto done;
1127 
1128 	if (hdrlen > size) {
1129 		err = got_error(GOT_ERR_BAD_OBJ_HDR);
1130 		goto done;
1131 	}
1132 
1133 	if (outbuf) {
1134 		if (close(outfd) != 0 && err == NULL)
1135 			err = got_error_from_errno("close");
1136 		outfd = -1;
1137 		(*blob)->f = fmemopen(outbuf, size, "rb");
1138 		if ((*blob)->f == NULL) {
1139 			err = got_error_from_errno("fmemopen");
1140 			free(outbuf);
1141 			goto done;
1142 		}
1143 		(*blob)->data = outbuf;
1144 	} else {
1145 		if (fstat(outfd, &sb) == -1) {
1146 			err = got_error_from_errno("fstat");
1147 			goto done;
1148 		}
1149 
1150 		if (sb.st_size != size) {
1151 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1152 			goto done;
1153 		}
1154 
1155 		(*blob)->f = fdopen(outfd, "rb");
1156 		if ((*blob)->f == NULL) {
1157 			err = got_error_from_errno("fdopen");
1158 			close(outfd);
1159 			outfd = -1;
1160 			goto done;
1161 		}
1162 	}
1163 
1164 	(*blob)->hdrlen = hdrlen;
1165 	(*blob)->blocksize = blocksize;
1166 	memcpy(&(*blob)->id.sha1, id->sha1, SHA1_DIGEST_LENGTH);
1167 
1168 done:
1169 	free(path_packfile);
1170 	if (err) {
1171 		if (*blob) {
1172 			got_object_blob_close(*blob);
1173 			*blob = NULL;
1174 		} else if (outfd != -1)
1175 			close(outfd);
1176 	}
1177 	return err;
1178 }
1179 
1180 const struct got_error *
1181 got_object_open_as_blob(struct got_blob_object **blob,
1182     struct got_repository *repo, struct got_object_id *id,
1183     size_t blocksize)
1184 {
1185 	return open_blob(blob, repo, id, blocksize);
1186 }
1187 
1188 const struct got_error *
1189 got_object_blob_open(struct got_blob_object **blob,
1190     struct got_repository *repo, struct got_object *obj, size_t blocksize)
1191 {
1192 	return open_blob(blob, repo, got_object_get_id(obj), blocksize);
1193 }
1194 
1195 const struct got_error *
1196 got_object_blob_close(struct got_blob_object *blob)
1197 {
1198 	const struct got_error *err = NULL;
1199 	free(blob->read_buf);
1200 	if (blob->f && fclose(blob->f) != 0)
1201 		err = got_error_from_errno("fclose");
1202 	free(blob->data);
1203 	free(blob);
1204 	return err;
1205 }
1206 
1207 void
1208 got_object_blob_rewind(struct got_blob_object *blob)
1209 {
1210 	if (blob->f)
1211 		rewind(blob->f);
1212 }
1213 
1214 char *
1215 got_object_blob_id_str(struct got_blob_object *blob, char *buf, size_t size)
1216 {
1217 	return got_sha1_digest_to_str(blob->id.sha1, buf, size);
1218 }
1219 
1220 size_t
1221 got_object_blob_get_hdrlen(struct got_blob_object *blob)
1222 {
1223 	return blob->hdrlen;
1224 }
1225 
1226 const uint8_t *
1227 got_object_blob_get_read_buf(struct got_blob_object *blob)
1228 {
1229 	return blob->read_buf;
1230 }
1231 
1232 const struct got_error *
1233 got_object_blob_read_block(size_t *outlenp, struct got_blob_object *blob)
1234 {
1235 	size_t n;
1236 
1237 	n = fread(blob->read_buf, 1, blob->blocksize, blob->f);
1238 	if (n == 0 && ferror(blob->f))
1239 		return got_ferror(blob->f, GOT_ERR_IO);
1240 	*outlenp = n;
1241 	return NULL;
1242 }
1243 
1244 const struct got_error *
1245 got_object_blob_dump_to_file(size_t *filesize, int *nlines,
1246     off_t **line_offsets, FILE *outfile, struct got_blob_object *blob)
1247 {
1248 	const struct got_error *err = NULL;
1249 	size_t n, len, hdrlen;
1250 	const uint8_t *buf;
1251 	int i;
1252 	size_t noffsets = 0;
1253 	off_t off = 0, total_len = 0;
1254 
1255 	if (line_offsets)
1256 		*line_offsets = NULL;
1257 	if (filesize)
1258 		*filesize = 0;
1259 	if (nlines)
1260 		*nlines = 0;
1261 
1262 	hdrlen = got_object_blob_get_hdrlen(blob);
1263 	do {
1264 		err = got_object_blob_read_block(&len, blob);
1265 		if (err)
1266 			return err;
1267 		if (len == 0)
1268 			break;
1269 		buf = got_object_blob_get_read_buf(blob);
1270 		i = hdrlen;
1271 		if (line_offsets && nlines) {
1272 			if (*line_offsets == NULL) {
1273 				/* Have some data but perhaps no '\n'. */
1274 				noffsets = 1;
1275 				*nlines = 1;
1276 				*line_offsets = calloc(1, sizeof(**line_offsets));
1277 				if (*line_offsets == NULL)
1278 					return got_error_from_errno("calloc");
1279 
1280 				/* Skip forward over end of first line. */
1281 				while (i < len) {
1282 					if (buf[i] == '\n')
1283 						break;
1284 					i++;
1285 				}
1286 			}
1287 			/* Scan '\n' offsets in remaining chunk of data. */
1288 			while (i < len) {
1289 				if (buf[i] != '\n') {
1290 					i++;
1291 					continue;
1292 				}
1293 				(*nlines)++;
1294 				if (noffsets < *nlines) {
1295 					off_t *o = recallocarray(*line_offsets,
1296 					    noffsets, *nlines,
1297 					    sizeof(**line_offsets));
1298 					if (o == NULL) {
1299 						free(*line_offsets);
1300 						*line_offsets = NULL;
1301 						return got_error_from_errno(
1302 						    "recallocarray");
1303 					}
1304 					*line_offsets = o;
1305 					noffsets = *nlines;
1306 				}
1307 				off = total_len + i - hdrlen + 1;
1308 				(*line_offsets)[*nlines - 1] = off;
1309 				i++;
1310 			}
1311 		}
1312 		/* Skip blob object header first time around. */
1313 		n = fwrite(buf + hdrlen, 1, len - hdrlen, outfile);
1314 		if (n != len - hdrlen)
1315 			return got_ferror(outfile, GOT_ERR_IO);
1316 		total_len += len - hdrlen;
1317 		hdrlen = 0;
1318 	} while (len != 0);
1319 
1320 	if (fflush(outfile) != 0)
1321 		return got_error_from_errno("fflush");
1322 	rewind(outfile);
1323 
1324 	if (filesize)
1325 		*filesize = total_len;
1326 
1327 	return NULL;
1328 }
1329 
1330 static const struct got_error *
1331 request_packed_tag(struct got_tag_object **tag, struct got_pack *pack,
1332     int pack_idx, struct got_object_id *id)
1333 {
1334 	const struct got_error *err = NULL;
1335 
1336 	err = got_privsep_send_tag_req(pack->privsep_child->ibuf, -1, id,
1337 	    pack_idx);
1338 	if (err)
1339 		return err;
1340 
1341 	return got_privsep_recv_tag(tag, pack->privsep_child->ibuf);
1342 }
1343 
1344 static const struct got_error *
1345 read_packed_tag_privsep(struct got_tag_object **tag,
1346     struct got_pack *pack, struct got_packidx *packidx, int idx,
1347     struct got_object_id *id)
1348 {
1349 	const struct got_error *err = NULL;
1350 
1351 	if (pack->privsep_child)
1352 		return request_packed_tag(tag, pack, idx, id);
1353 
1354 	err = start_pack_privsep_child(pack, packidx);
1355 	if (err)
1356 		return err;
1357 
1358 	return request_packed_tag(tag, pack, idx, id);
1359 }
1360 
1361 static const struct got_error *
1362 request_tag(struct got_tag_object **tag, struct got_repository *repo,
1363     int fd)
1364 {
1365 	const struct got_error *err = NULL;
1366 	struct imsgbuf *ibuf;
1367 
1368 	ibuf = repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_TAG].ibuf;
1369 
1370 	err = got_privsep_send_tag_req(ibuf, fd, NULL, -1);
1371 	if (err)
1372 		return err;
1373 
1374 	return got_privsep_recv_tag(tag, ibuf);
1375 }
1376 
1377 static const struct got_error *
1378 read_tag_privsep(struct got_tag_object **tag, int obj_fd,
1379     struct got_repository *repo)
1380 {
1381 	const struct got_error *err;
1382 	int imsg_fds[2];
1383 	pid_t pid;
1384 	struct imsgbuf *ibuf;
1385 
1386 	if (repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_TAG].imsg_fd != -1)
1387 		return request_tag(tag, repo, obj_fd);
1388 
1389 	ibuf = calloc(1, sizeof(*ibuf));
1390 	if (ibuf == NULL)
1391 		return got_error_from_errno("calloc");
1392 
1393 	if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, imsg_fds) == -1) {
1394 		err = got_error_from_errno("socketpair");
1395 		free(ibuf);
1396 		return err;
1397 	}
1398 
1399 	pid = fork();
1400 	if (pid == -1) {
1401 		err = got_error_from_errno("fork");
1402 		free(ibuf);
1403 		return err;
1404 	}
1405 	else if (pid == 0) {
1406 		got_privsep_exec_child(imsg_fds, GOT_PATH_PROG_READ_TAG,
1407 		    repo->path);
1408 		/* not reached */
1409 	}
1410 
1411 	if (close(imsg_fds[1]) != 0) {
1412 		err = got_error_from_errno("close");
1413 		free(ibuf);
1414 		return err;
1415 	}
1416 	repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_TAG].imsg_fd =
1417 	    imsg_fds[0];
1418 	repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_TAG].pid = pid;
1419 	imsg_init(ibuf, imsg_fds[0]);
1420 	repo->privsep_children[GOT_REPO_PRIVSEP_CHILD_TAG].ibuf = ibuf;
1421 
1422 	return request_tag(tag, repo, obj_fd);
1423 }
1424 
1425 static const struct got_error *
1426 open_tag(struct got_tag_object **tag, struct got_repository *repo,
1427     struct got_object_id *id, int check_cache)
1428 {
1429 	const struct got_error *err = NULL;
1430 	struct got_packidx *packidx = NULL;
1431 	int idx;
1432 	char *path_packfile = NULL;
1433 	struct got_object *obj = NULL;
1434 	int obj_type = GOT_OBJ_TYPE_ANY;
1435 
1436 	if (check_cache) {
1437 		*tag = got_repo_get_cached_tag(repo, id);
1438 		if (*tag != NULL) {
1439 			(*tag)->refcnt++;
1440 			return NULL;
1441 		}
1442 	} else
1443 		*tag = NULL;
1444 
1445 	err = got_repo_search_packidx(&packidx, &idx, repo, id);
1446 	if (err == NULL) {
1447 		struct got_pack *pack = NULL;
1448 
1449 		err = get_packfile_path(&path_packfile, packidx);
1450 		if (err)
1451 			return err;
1452 
1453 		pack = got_repo_get_cached_pack(repo, path_packfile);
1454 		if (pack == NULL) {
1455 			err = got_repo_cache_pack(&pack, repo, path_packfile,
1456 			    packidx);
1457 			if (err)
1458 				goto done;
1459 		}
1460 
1461 		/* Beware of "lightweight" tags: Check object type first. */
1462 		err = read_packed_object_privsep(&obj, repo, pack, packidx,
1463 		    idx, id);
1464 		if (err)
1465 			goto done;
1466 		obj_type = obj->type;
1467 		got_object_close(obj);
1468 		if (obj_type != GOT_OBJ_TYPE_TAG) {
1469 			err = got_error(GOT_ERR_OBJ_TYPE);
1470 			goto done;
1471 		}
1472 		err = read_packed_tag_privsep(tag, pack, packidx, idx, id);
1473 	} else if (err->code == GOT_ERR_NO_OBJ) {
1474 		int fd;
1475 
1476 		err = open_loose_object(&fd, id, repo);
1477 		if (err)
1478 			return err;
1479 		err = read_object_header_privsep(&obj, repo, fd);
1480 		if (err)
1481 			return err;
1482 		obj_type = obj->type;
1483 		got_object_close(obj);
1484 		if (obj_type != GOT_OBJ_TYPE_TAG)
1485 			return got_error(GOT_ERR_OBJ_TYPE);
1486 
1487 		err = open_loose_object(&fd, id, repo);
1488 		if (err)
1489 			return err;
1490 		err = read_tag_privsep(tag, fd, repo);
1491 	}
1492 
1493 	if (err == NULL) {
1494 		(*tag)->refcnt++;
1495 		err = got_repo_cache_tag(repo, id, *tag);
1496 	}
1497 done:
1498 	free(path_packfile);
1499 	return err;
1500 }
1501 
1502 const struct got_error *
1503 got_object_open_as_tag(struct got_tag_object **tag,
1504     struct got_repository *repo, struct got_object_id *id)
1505 {
1506 	*tag = got_repo_get_cached_tag(repo, id);
1507 	if (*tag != NULL) {
1508 		(*tag)->refcnt++;
1509 		return NULL;
1510 	}
1511 
1512 	return open_tag(tag, repo, id, 0);
1513 }
1514 
1515 const struct got_error *
1516 got_object_tag_open(struct got_tag_object **tag,
1517     struct got_repository *repo, struct got_object *obj)
1518 {
1519 	return open_tag(tag, repo, got_object_get_id(obj), 1);
1520 }
1521 
1522 const char *
1523 got_object_tag_get_name(struct got_tag_object *tag)
1524 {
1525 	return tag->tag;
1526 }
1527 
1528 int
1529 got_object_tag_get_object_type(struct got_tag_object *tag)
1530 {
1531 	return tag->obj_type;
1532 }
1533 
1534 struct got_object_id *
1535 got_object_tag_get_object_id(struct got_tag_object *tag)
1536 {
1537 	return &tag->id;
1538 }
1539 
1540 time_t
1541 got_object_tag_get_tagger_time(struct got_tag_object *tag)
1542 {
1543 	return tag->tagger_time;
1544 }
1545 
1546 time_t
1547 got_object_tag_get_tagger_gmtoff(struct got_tag_object *tag)
1548 {
1549 	return tag->tagger_gmtoff;
1550 }
1551 
1552 const char *
1553 got_object_tag_get_tagger(struct got_tag_object *tag)
1554 {
1555 	return tag->tagger;
1556 }
1557 
1558 const char *
1559 got_object_tag_get_message(struct got_tag_object *tag)
1560 {
1561 	return tag->tagmsg;
1562 }
1563 
1564 static struct got_tree_entry *
1565 find_entry_by_name(struct got_tree_object *tree, const char *name, size_t len)
1566 {
1567 	int i;
1568 
1569 	/* Note that tree entries are sorted in strncmp() order. */
1570 	for (i = 0; i < tree->nentries; i++) {
1571 		struct got_tree_entry *te = &tree->entries[i];
1572 		int cmp = strncmp(te->name, name, len);
1573 		if (cmp < 0)
1574 			continue;
1575 		if (cmp > 0)
1576 			break;
1577 		if (te->name[len] == '\0')
1578 			return te;
1579 	}
1580 	return NULL;
1581 }
1582 
1583 struct got_tree_entry *
1584 got_object_tree_find_entry(struct got_tree_object *tree, const char *name)
1585 {
1586 	return find_entry_by_name(tree, name, strlen(name));
1587 }
1588 
1589 const struct got_error *
1590 got_object_id_by_path(struct got_object_id **id, struct got_repository *repo,
1591     struct got_object_id *commit_id, const char *path)
1592 {
1593 	const struct got_error *err = NULL;
1594 	struct got_commit_object *commit = NULL;
1595 	struct got_tree_object *tree = NULL;
1596 	struct got_tree_entry *te = NULL;
1597 	const char *seg, *s;
1598 	size_t seglen;
1599 
1600 	*id = NULL;
1601 
1602 	err = got_object_open_as_commit(&commit, repo, commit_id);
1603 	if (err)
1604 		goto done;
1605 
1606 	/* Handle opening of root of commit's tree. */
1607 	if (got_path_is_root_dir(path)) {
1608 		*id = got_object_id_dup(commit->tree_id);
1609 		if (*id == NULL)
1610 			err = got_error_from_errno("got_object_id_dup");
1611 		goto done;
1612 	}
1613 
1614 	err = got_object_open_as_tree(&tree, repo, commit->tree_id);
1615 	if (err)
1616 		goto done;
1617 
1618 	s = path;
1619 	while (s[0] == '/')
1620 		s++;
1621 	seg = s;
1622 	seglen = 0;
1623 	while (*s) {
1624 		struct got_tree_object *next_tree;
1625 
1626 		if (*s != '/') {
1627 			s++;
1628 			seglen++;
1629 			if (*s)
1630 				continue;
1631 		}
1632 
1633 		te = find_entry_by_name(tree, seg, seglen);
1634 		if (te == NULL) {
1635 			err = got_error(GOT_ERR_NO_TREE_ENTRY);
1636 			goto done;
1637 		}
1638 
1639 		if (*s == '\0')
1640 			break;
1641 
1642 		seg = s + 1;
1643 		seglen = 0;
1644 		s++;
1645 		if (*s) {
1646 			err = got_object_open_as_tree(&next_tree, repo,
1647 			    &te->id);
1648 			te = NULL;
1649 			if (err)
1650 				goto done;
1651 			got_object_tree_close(tree);
1652 			tree = next_tree;
1653 		}
1654 	}
1655 
1656 	if (te) {
1657 		*id = got_object_id_dup(&te->id);
1658 		if (*id == NULL)
1659 			return got_error_from_errno("got_object_id_dup");
1660 	} else
1661 		err = got_error(GOT_ERR_NO_TREE_ENTRY);
1662 done:
1663 	if (commit)
1664 		got_object_commit_close(commit);
1665 	if (tree)
1666 		got_object_tree_close(tree);
1667 	return err;
1668 }
1669 
1670 /*
1671  * Normalize file mode bits to avoid false positive tree entry differences
1672  * in case tree entries have unexpected mode bits set.
1673  */
1674 static mode_t
1675 normalize_mode_for_comparison(mode_t mode)
1676 {
1677 	/*
1678 	 * For directories, the only relevant bit is the IFDIR bit.
1679 	 * This allows us to detect paths changing from a directory
1680 	 * to a file and vice versa.
1681 	 */
1682 	if (S_ISDIR(mode))
1683 		return mode & S_IFDIR;
1684 
1685 	/* For files, the only change we care about is the executable bit. */
1686 	return mode & S_IXUSR;
1687 }
1688 
1689 const struct got_error *
1690 got_object_tree_path_changed(int *changed,
1691     struct got_tree_object *tree01, struct got_tree_object *tree02,
1692     const char *path, struct got_repository *repo)
1693 {
1694 	const struct got_error *err = NULL;
1695 	struct got_tree_object *tree1 = NULL, *tree2 = NULL;
1696 	struct got_tree_entry *te1 = NULL, *te2 = NULL;
1697 	const char *seg, *s;
1698 	size_t seglen;
1699 
1700 	*changed = 0;
1701 
1702 	/* We not do support comparing the root path. */
1703 	if (got_path_is_root_dir(path))
1704 		return got_error_path(path, GOT_ERR_BAD_PATH);
1705 
1706 	tree1 = tree01;
1707 	tree2 = tree02;
1708 	s = path;
1709 	while (*s == '/')
1710 		s++;
1711 	seg = s;
1712 	seglen = 0;
1713 	while (*s) {
1714 		struct got_tree_object *next_tree1, *next_tree2;
1715 		mode_t mode1, mode2;
1716 
1717 		if (*s != '/') {
1718 			s++;
1719 			seglen++;
1720 			if (*s)
1721 				continue;
1722 		}
1723 
1724 		te1 = find_entry_by_name(tree1, seg, seglen);
1725 		if (te1 == NULL) {
1726 			err = got_error(GOT_ERR_NO_OBJ);
1727 			goto done;
1728 		}
1729 
1730 		te2 = find_entry_by_name(tree2, seg, seglen);
1731 		if (te2 == NULL) {
1732 			*changed = 1;
1733 			goto done;
1734 		}
1735 
1736 		mode1 = normalize_mode_for_comparison(te1->mode);
1737 		mode2 = normalize_mode_for_comparison(te2->mode);
1738 		if (mode1 != mode2) {
1739 			*changed = 1;
1740 			goto done;
1741 		}
1742 
1743 		if (got_object_id_cmp(&te1->id, &te2->id) == 0) {
1744 			*changed = 0;
1745 			goto done;
1746 		}
1747 
1748 		if (*s == '\0') { /* final path element */
1749 			*changed = 1;
1750 			goto done;
1751 		}
1752 
1753 		seg = s + 1;
1754 		s++;
1755 		seglen = 0;
1756 		if (*s) {
1757 			err = got_object_open_as_tree(&next_tree1, repo,
1758 			    &te1->id);
1759 			te1 = NULL;
1760 			if (err)
1761 				goto done;
1762 			if (tree1 != tree01)
1763 				got_object_tree_close(tree1);
1764 			tree1 = next_tree1;
1765 
1766 			err = got_object_open_as_tree(&next_tree2, repo,
1767 			    &te2->id);
1768 			te2 = NULL;
1769 			if (err)
1770 				goto done;
1771 			if (tree2 != tree02)
1772 				got_object_tree_close(tree2);
1773 			tree2 = next_tree2;
1774 		}
1775 	}
1776 done:
1777 	if (tree1 && tree1 != tree01)
1778 		got_object_tree_close(tree1);
1779 	if (tree2 && tree2 != tree02)
1780 		got_object_tree_close(tree2);
1781 	return err;
1782 }
1783 
1784 const struct got_error *
1785 got_object_tree_entry_dup(struct got_tree_entry **new_te,
1786     struct got_tree_entry *te)
1787 {
1788 	const struct got_error *err = NULL;
1789 
1790 	*new_te = calloc(1, sizeof(**new_te));
1791 	if (*new_te == NULL)
1792 		return got_error_from_errno("calloc");
1793 
1794 	(*new_te)->mode = te->mode;
1795 	memcpy((*new_te)->name, te->name, sizeof((*new_te)->name));
1796 	memcpy(&(*new_te)->id, &te->id, sizeof((*new_te)->id));
1797 	return err;
1798 }
1799 
1800 int
1801 got_object_tree_entry_is_submodule(struct got_tree_entry *te)
1802 {
1803 	return (te->mode & S_IFMT) == (S_IFDIR | S_IFLNK);
1804 }
1805 
1806 const struct got_error *
1807 got_traverse_packed_commits(struct got_object_id_queue *traversed_commits,
1808     struct got_object_id *commit_id, const char *path,
1809     struct got_repository *repo)
1810 {
1811 	const struct got_error *err = NULL;
1812 	struct got_pack *pack = NULL;
1813 	struct got_packidx *packidx = NULL;
1814 	char *path_packfile = NULL;
1815 	struct got_commit_object *changed_commit = NULL;
1816 	struct got_object_id *changed_commit_id = NULL;
1817 	int idx;
1818 
1819 	err = got_repo_search_packidx(&packidx, &idx, repo, commit_id);
1820 	if (err) {
1821 		if (err->code != GOT_ERR_NO_OBJ)
1822 			return err;
1823 		return NULL;
1824 	}
1825 
1826 	err = get_packfile_path(&path_packfile, packidx);
1827 	if (err)
1828 		return err;
1829 
1830 	pack = got_repo_get_cached_pack(repo, path_packfile);
1831 	if (pack == NULL) {
1832 		err = got_repo_cache_pack(&pack, repo, path_packfile, packidx);
1833 		if (err)
1834 			goto done;
1835 	}
1836 
1837 	if (pack->privsep_child == NULL) {
1838 		err = start_pack_privsep_child(pack, packidx);
1839 		if (err)
1840 			goto done;
1841 	}
1842 
1843 	err = got_privsep_send_commit_traversal_request(
1844 	    pack->privsep_child->ibuf, commit_id, idx, path);
1845 	if (err)
1846 		goto done;
1847 
1848 	err = got_privsep_recv_traversed_commits(&changed_commit,
1849 	    &changed_commit_id, traversed_commits, pack->privsep_child->ibuf);
1850 	if (err)
1851 		goto done;
1852 
1853 	if (changed_commit) {
1854 		/*
1855 		 * Cache the commit in which the path was changed.
1856 		 * This commit might be opened again soon.
1857 		 */
1858 		changed_commit->refcnt++;
1859 		err = got_repo_cache_commit(repo, changed_commit_id,
1860 		    changed_commit);
1861 		got_object_commit_close(changed_commit);
1862 	}
1863 done:
1864 	free(path_packfile);
1865 	free(changed_commit_id);
1866 	return err;
1867 }