1 /*
2  * Copyright (c) 2022 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 "got_compat.h"
18 
19 #include <sys/queue.h>
20 #include <sys/stat.h>
21 
22 #include <errno.h>
23 #include <limits.h>
24 #include <stdio.h>
25 #include <stdlib.h>
26 #include <string.h>
27 #include <unistd.h>
28 
29 #include "got_error.h"
30 #include "got_object.h"
31 #include "got_repository.h"
32 #include "got_path.h"
33 
34 #include "got_lib_delta.h"
35 #include "got_lib_object.h"
36 #include "got_lib_object_cache.h"
37 #include "got_lib_object_parse.h"
38 #include "got_lib_pack.h"
39 #include "got_lib_repository.h"
40 
41 const struct got_error *
42 got_object_open_packed(struct got_object **obj, struct got_object_id *id,
43     struct got_repository *repo)
44 {
45 	const struct got_error *err = NULL;
46 	struct got_pack *pack = NULL;
47 	struct got_packidx *packidx = NULL;
48 	int idx;
49 	char *path_packfile;
50 
51 	err = got_repo_search_packidx(&packidx, &idx, repo, id);
52 	if (err)
53 		return err;
54 
55 	err = got_packidx_get_packfile_path(&path_packfile,
56 	    packidx->path_packidx);
57 	if (err)
58 		return err;
59 
60 	pack = got_repo_get_cached_pack(repo, path_packfile);
61 	if (pack == NULL) {
62 		err = got_repo_cache_pack(&pack, repo, path_packfile, packidx);
63 		if (err)
64 			goto done;
65 	}
66 
67 	err = got_packfile_open_object(obj, pack, packidx, idx, id);
68 	if (err)
69 		return err;
70 	(*obj)->refcnt++;
71 
72 	err = got_repo_cache_object(repo, id, *obj);
73 	if (err) {
74 		if (err->code == GOT_ERR_OBJ_EXISTS ||
75 		    err->code == GOT_ERR_OBJ_TOO_LARGE)
76 			err = NULL;
77 	}
78 done:
79 	free(path_packfile);
80 	return err;
81 }
82 
83 const struct got_error *
84 got_object_open_from_packfile(struct got_object **obj, struct got_object_id *id,
85     struct got_pack *pack, struct got_packidx *packidx, int obj_idx,
86     struct got_repository *repo)
87 {
88 	const struct got_error *err;
89 
90 	*obj = got_repo_get_cached_object(repo, id);
91 	if (*obj != NULL) {
92 		(*obj)->refcnt++;
93 		return NULL;
94 	}
95 
96 	err = got_packfile_open_object(obj, pack, packidx, obj_idx, id);
97 	if (err)
98 		return err;
99 	(*obj)->refcnt++;
100 
101 	err = got_repo_cache_object(repo, id, *obj);
102 	if (err) {
103 		if (err->code == GOT_ERR_OBJ_EXISTS ||
104 		    err->code == GOT_ERR_OBJ_TOO_LARGE)
105 			err = NULL;
106 		return err;
107 	}
108 	(*obj)->refcnt++;
109 	return NULL;
110 }
111 
112 const struct got_error *
113 got_object_read_raw_delta(uint64_t *base_size, uint64_t *result_size,
114     off_t *delta_size, off_t *delta_compressed_size, off_t *delta_offset,
115     off_t *delta_out_offset, struct got_object_id **base_id, int delta_cache_fd,
116     struct got_packidx *packidx, int obj_idx, struct got_object_id *id,
117     struct got_repository *repo)
118 {
119 	return got_error(GOT_ERR_NOT_IMPL);
120 }
121 
122 const struct got_error *
123 got_object_open(struct got_object **obj, struct got_repository *repo,
124     struct got_object_id *id)
125 {
126 	const struct got_error *err = NULL;
127 	int fd;
128 
129 	*obj = got_repo_get_cached_object(repo, id);
130 	if (*obj != NULL) {
131 		(*obj)->refcnt++;
132 		return NULL;
133 	}
134 
135 	err = got_object_open_packed(obj, id, repo);
136 	if (err) {
137 		if (err->code != GOT_ERR_NO_OBJ)
138 			return err;
139 	} else
140 		return NULL;
141 
142 	err = got_object_open_loose_fd(&fd, id, repo);
143 	if (err) {
144 		if (err->code == GOT_ERR_ERRNO && errno == ENOENT)
145 			err = got_error_no_obj(id);
146 		return err;
147 	}
148 
149 	err = got_object_read_header(obj, fd);
150 	if (err)
151 		goto done;
152 
153 	memcpy(&(*obj)->id, id, sizeof((*obj)->id));
154 	(*obj)->refcnt++;
155 
156 	err = got_repo_cache_object(repo, id, *obj);
157 	if (err) {
158 		if (err->code == GOT_ERR_OBJ_EXISTS ||
159 		    err->code == GOT_ERR_OBJ_TOO_LARGE)
160 			err = NULL;
161 	}
162 done:
163 	if (close(fd) == -1 && err == NULL)
164 		err = got_error_from_errno("close");
165 	return err;
166 }
167 
168 static const struct got_error *
169 wrap_fd(FILE **f, int wrapped_fd)
170 {
171 	const struct got_error *err = NULL;
172 	int fd;
173 
174 	if (ftruncate(wrapped_fd, 0L) == -1)
175 		return got_error_from_errno("ftruncate");
176 
177 	if (lseek(wrapped_fd, 0L, SEEK_SET) == -1)
178 		return got_error_from_errno("lseek");
179 
180 	fd = dup(wrapped_fd);
181 	if (fd == -1)
182 		return got_error_from_errno("dup");
183 
184 	*f = fdopen(fd, "w+");
185 	if (*f == NULL) {
186 		err = got_error_from_errno("fdopen");
187 		close(fd);
188 	}
189 	return err;
190 }
191 
192 static const struct got_error *
193 read_packed_object_raw(uint8_t **outbuf, off_t *size, size_t *hdrlen,
194     int outfd, struct got_pack *pack, struct got_packidx *packidx, int idx,
195     struct got_object_id *id)
196 {
197 	const struct got_error *err = NULL;
198 	uint64_t raw_size = 0;
199 	struct got_object *obj;
200 	FILE *outfile = NULL, *basefile = NULL, *accumfile = NULL;
201 
202 	*outbuf = NULL;
203 	*size = 0;
204 	*hdrlen = 0;
205 
206 	err = got_packfile_open_object(&obj, pack, packidx, idx, id);
207 	if (err)
208 		return err;
209 
210 	if (obj->flags & GOT_OBJ_FLAG_DELTIFIED) {
211 		err = got_pack_get_max_delta_object_size(&raw_size, obj, pack);
212 		if (err)
213 			goto done;
214 	} else
215 		raw_size = obj->size;
216 
217 	if (raw_size <= GOT_DELTA_RESULT_SIZE_CACHED_MAX) {
218 		size_t len;
219 		err = got_packfile_extract_object_to_mem(outbuf, &len,
220 		    obj, pack);
221 		if (err)
222 			goto done;
223 		*size = (off_t)len;
224 	} else {
225 		/*
226 		 * XXX This uses 3 file extra descriptors for no good reason.
227 		 * We should have got_packfile_extract_object_to_fd().
228 		 */
229 		err = wrap_fd(&outfile, outfd);
230 		if (err)
231 			goto done;
232 		err = wrap_fd(&basefile, pack->basefd);
233 		if (err)
234 			goto done;
235 		err = wrap_fd(&accumfile, pack->accumfd);
236 		if (err)
237 			goto done;
238 		err = got_packfile_extract_object(pack, obj, outfile, basefile,
239 		    accumfile);
240 		if (err)
241 			goto done;
242 		*size = obj->size;
243 	}
244 
245 	*hdrlen = obj->hdrlen;
246 done:
247 	got_object_close(obj);
248 	if (outfile && fclose(outfile) == EOF && err == NULL)
249 		err = got_error_from_errno("fclose");
250 	if (basefile && fclose(basefile) == EOF && err == NULL)
251 		err = got_error_from_errno("fclose");
252 	if (accumfile && fclose(accumfile) == EOF && err == NULL)
253 		err = got_error_from_errno("fclose");
254 	return err;
255 
256 }
257 
258 static void
259 put_raw_object_tempfile(struct got_raw_object *obj)
260 {
261 	struct got_repository *repo = obj->close_arg;
262 
263 	if (obj->tempfile_idx != -1)
264 		got_repo_temp_fds_put(obj->tempfile_idx, repo);
265 }
266 
267 /* *outfd must be initialized to -1 by caller */
268 const struct got_error *
269 got_object_raw_open(struct got_raw_object **obj, int *outfd,
270     struct got_repository *repo, struct got_object_id *id)
271 {
272 	const struct got_error *err = NULL;
273 	struct got_packidx *packidx = NULL;
274 	int idx, tempfd, tempfile_idx;
275 	uint8_t *outbuf = NULL;
276 	off_t size = 0;
277 	size_t hdrlen = 0;
278 	char *path_packfile = NULL;
279 
280 	*obj = got_repo_get_cached_raw_object(repo, id);
281 	if (*obj != NULL) {
282 		(*obj)->refcnt++;
283 		return NULL;
284 	}
285 
286 	err = got_repo_temp_fds_get(&tempfd, &tempfile_idx, repo);
287 	if (err)
288 		return err;
289 
290 	err = got_repo_search_packidx(&packidx, &idx, repo, id);
291 	if (err == NULL) {
292 		struct got_pack *pack = NULL;
293 
294 		err = got_packidx_get_packfile_path(&path_packfile,
295 		    packidx->path_packidx);
296 		if (err)
297 			goto done;
298 
299 		pack = got_repo_get_cached_pack(repo, path_packfile);
300 		if (pack == NULL) {
301 			err = got_repo_cache_pack(&pack, repo, path_packfile,
302 			    packidx);
303 			if (err)
304 				goto done;
305 		}
306 		err = read_packed_object_raw(&outbuf, &size, &hdrlen,
307 		    tempfd, pack, packidx, idx, id);
308 		if (err)
309 			goto done;
310 	} else if (err->code == GOT_ERR_NO_OBJ) {
311 		int fd;
312 
313 		err = got_object_open_loose_fd(&fd, id, repo);
314 		if (err)
315 			goto done;
316 		err = got_object_read_raw(&outbuf, &size, &hdrlen,
317 		    GOT_DELTA_RESULT_SIZE_CACHED_MAX, tempfd, id, fd);
318 		if (close(fd) == -1 && err == NULL)
319 			err = got_error_from_errno("close");
320 		if (err)
321 			goto done;
322 	}
323 
324 	if (outbuf == NULL) {
325 		if (*outfd != -1) {
326 			err = got_error_msg(GOT_ERR_NOT_IMPL, "bad outfd");
327 			goto done;
328 		}
329 
330 		/*
331 		 * Duplicate tempfile descriptor to allow use of
332 		 * fdopen(3) inside got_object_raw_alloc().
333 		 */
334 		*outfd = dup(tempfd);
335 		if (*outfd == -1) {
336 			err = got_error_from_errno("dup");
337 			goto done;
338 		}
339 	}
340 
341 	err = got_object_raw_alloc(obj, outbuf, outfd,
342 	    GOT_DELTA_RESULT_SIZE_CACHED_MAX, hdrlen, size);
343 	if (err)
344 		goto done;
345 
346 	err = got_repo_cache_raw_object(repo, id, *obj);
347 	if (err) {
348 		if (err->code == GOT_ERR_OBJ_EXISTS ||
349 		    err->code == GOT_ERR_OBJ_TOO_LARGE)
350 			err = NULL;
351 	}
352 done:
353 	free(path_packfile);
354 	if (err) {
355 		if (*obj) {
356 			got_object_raw_close(*obj);
357 			*obj = NULL;
358 		}
359 		free(outbuf);
360 		got_repo_temp_fds_put(tempfile_idx, repo);
361 		if (*outfd != -1) {
362 			close(*outfd);
363 			*outfd = -1;
364 		}
365 	} else {
366 		if (((*obj)->f == NULL && (*obj)->fd == -1)) {
367 			/* This raw object is not backed by a file. */
368 			got_repo_temp_fds_put(tempfile_idx, repo);
369 			if (*outfd != -1) {
370 				close(*outfd);
371 				*outfd = -1;
372 			}
373 		} else {
374 			(*obj)->tempfile_idx = tempfile_idx;
375 			(*obj)->close_cb = put_raw_object_tempfile;
376 			(*obj)->close_arg = repo;
377 		}
378 	}
379 	return err;
380 }
381 
382 static const struct got_error *
383 open_commit(struct got_commit_object **commit,
384     struct got_repository *repo, struct got_object_id *id, int check_cache)
385 {
386 	const struct got_error *err = NULL;
387 	struct got_packidx *packidx = NULL;
388 	int idx;
389 	char *path_packfile = NULL;
390 
391 	if (check_cache) {
392 		*commit = got_repo_get_cached_commit(repo, id);
393 		if (*commit != NULL) {
394 			(*commit)->refcnt++;
395 			return NULL;
396 		}
397 	} else
398 		*commit = NULL;
399 
400 	err = got_repo_search_packidx(&packidx, &idx, repo, id);
401 	if (err == NULL) {
402 		struct got_pack *pack = NULL;
403 		struct got_object *obj;
404 		uint8_t *buf;
405 		size_t len;
406 
407 		err = got_packidx_get_packfile_path(&path_packfile,
408 		    packidx->path_packidx);
409 		if (err)
410 			return err;
411 
412 		pack = got_repo_get_cached_pack(repo, path_packfile);
413 		if (pack == NULL) {
414 			err = got_repo_cache_pack(&pack, repo, path_packfile,
415 			    packidx);
416 			if (err)
417 				goto done;
418 		}
419 		err = got_packfile_open_object(&obj, pack, packidx, idx, id);
420 		if (err)
421 			goto done;
422 		err = got_packfile_extract_object_to_mem(&buf, &len,
423 		    obj, pack);
424 		got_object_close(obj);
425 		if (err)
426 			goto done;
427 		err = got_object_parse_commit(commit, buf, len);
428 		free(buf);
429 	} else if (err->code == GOT_ERR_NO_OBJ) {
430 		int fd;
431 
432 		err = got_object_open_loose_fd(&fd, id, repo);
433 		if (err)
434 			return err;
435 		err = got_object_read_commit(commit, fd, id, 0);
436 		if (close(fd) == -1 && err == NULL)
437 			err = got_error_from_errno("close");
438 		if (err)
439 			return err;
440 	}
441 
442 	if (err == NULL) {
443 		(*commit)->refcnt++;
444 		err = got_repo_cache_commit(repo, id, *commit);
445 		if (err) {
446 			if (err->code == GOT_ERR_OBJ_EXISTS ||
447 			    err->code == GOT_ERR_OBJ_TOO_LARGE)
448 				err = NULL;
449 		}
450 	}
451 done:
452 	free(path_packfile);
453 	return err;
454 }
455 
456 const struct got_error *
457 got_object_open_as_commit(struct got_commit_object **commit,
458     struct got_repository *repo, struct got_object_id *id)
459 {
460 	*commit = got_repo_get_cached_commit(repo, id);
461 	if (*commit != NULL) {
462 		(*commit)->refcnt++;
463 		return NULL;
464 	}
465 
466 	return open_commit(commit, repo, id, 0);
467 }
468 
469 const struct got_error *
470 got_object_commit_open(struct got_commit_object **commit,
471     struct got_repository *repo, struct got_object *obj)
472 {
473 	return open_commit(commit, repo, got_object_get_id(obj), 1);
474 }
475 
476 static const struct got_error *
477 open_tree(struct got_tree_object **tree,
478     struct got_repository *repo, struct got_object_id *id, int check_cache)
479 {
480 	const struct got_error *err = NULL;
481 	struct got_packidx *packidx = NULL;
482 	int idx;
483 	char *path_packfile = NULL;
484 	struct got_parsed_tree_entry *entries = NULL;
485 	size_t nentries = 0, nentries_alloc = 0, i;
486 	uint8_t *buf = NULL;
487 
488 	if (check_cache) {
489 		*tree = got_repo_get_cached_tree(repo, id);
490 		if (*tree != NULL) {
491 			(*tree)->refcnt++;
492 			return NULL;
493 		}
494 	} else
495 		*tree = NULL;
496 
497 	err = got_repo_search_packidx(&packidx, &idx, repo, id);
498 	if (err == NULL) {
499 		struct got_pack *pack = NULL;
500 		struct got_object *obj;
501 		size_t len;
502 
503 		err = got_packidx_get_packfile_path(&path_packfile,
504 		    packidx->path_packidx);
505 		if (err)
506 			return err;
507 
508 		pack = got_repo_get_cached_pack(repo, path_packfile);
509 		if (pack == NULL) {
510 			err = got_repo_cache_pack(&pack, repo, path_packfile,
511 			    packidx);
512 			if (err)
513 				goto done;
514 		}
515 		err = got_packfile_open_object(&obj, pack, packidx, idx, id);
516 		if (err)
517 			goto done;
518 		err = got_packfile_extract_object_to_mem(&buf, &len,
519 		    obj, pack);
520 		got_object_close(obj);
521 		if (err)
522 			goto done;
523 		err = got_object_parse_tree(&entries, &nentries,
524 		    &nentries_alloc, buf, len);
525 		if (err)
526 			goto done;
527 	} else if (err->code == GOT_ERR_NO_OBJ) {
528 		int fd;
529 
530 		err = got_object_open_loose_fd(&fd, id, repo);
531 		if (err)
532 			return err;
533 		err = got_object_read_tree(&entries, &nentries,
534 		    &nentries_alloc, &buf, fd, id);
535 		if (close(fd) == -1 && err == NULL)
536 			err = got_error_from_errno("close");
537 		if (err)
538 			goto done;
539 	} else
540 		goto done;
541 
542 	*tree = malloc(sizeof(**tree));
543 	if (*tree == NULL) {
544 		err = got_error_from_errno("malloc");
545 		goto done;
546 	}
547 	(*tree)->entries = calloc(nentries, sizeof(struct got_tree_entry));
548 	if ((*tree)->entries == NULL) {
549 		err = got_error_from_errno("malloc");
550 		goto done;
551 	}
552 	(*tree)->nentries = nentries;
553 	(*tree)->refcnt = 0;
554 
555 	for (i = 0; i < nentries; i++) {
556 		struct got_parsed_tree_entry *pe = &entries[i];
557 		struct got_tree_entry *te = &(*tree)->entries[i];
558 	
559 		if (strlcpy(te->name, pe->name,
560 		    sizeof(te->name)) >= sizeof(te->name)) {
561 			err = got_error(GOT_ERR_NO_SPACE);
562 			goto done;
563 		}
564 		memcpy(te->id.sha1, pe->id, SHA1_DIGEST_LENGTH);
565 		te->mode = pe->mode;
566 		te->idx = i;
567 	}
568 done:
569 	free(path_packfile);
570 	free(entries);
571 	free(buf);
572 	if (err == NULL) {
573 		(*tree)->refcnt++;
574 		err = got_repo_cache_tree(repo, id, *tree);
575 		if (err) {
576 			if (err->code == GOT_ERR_OBJ_EXISTS ||
577 			    err->code == GOT_ERR_OBJ_TOO_LARGE)
578 				err = NULL;
579 		}
580 	}
581 	if (err) {
582 		if (*tree)
583 			free((*tree)->entries);
584 		free(*tree);
585 		*tree = NULL;
586 	}
587 	return err;
588 }
589 
590 const struct got_error *
591 got_object_open_as_tree(struct got_tree_object **tree,
592     struct got_repository *repo, struct got_object_id *id)
593 {
594 	*tree = got_repo_get_cached_tree(repo, id);
595 	if (*tree != NULL) {
596 		(*tree)->refcnt++;
597 		return NULL;
598 	}
599 
600 	return open_tree(tree, repo, id, 0);
601 }
602 
603 const struct got_error *
604 got_object_tree_open(struct got_tree_object **tree,
605     struct got_repository *repo, struct got_object *obj)
606 {
607 	return open_tree(tree, repo, got_object_get_id(obj), 1);
608 }
609 
610 const struct got_error *
611 got_object_open_as_blob(struct got_blob_object **blob,
612     struct got_repository *repo, struct got_object_id *id, size_t blocksize,
613     int outfd)
614 {
615 	return got_error(GOT_ERR_NOT_IMPL);
616 }
617 
618 const struct got_error *
619 got_object_blob_open(struct got_blob_object **blob,
620     struct got_repository *repo, struct got_object *obj, size_t blocksize,
621     int outfd)
622 {
623 	return got_error(GOT_ERR_NOT_IMPL);
624 }
625 
626 static const struct got_error *
627 open_tag(struct got_tag_object **tag, struct got_repository *repo,
628     struct got_object_id *id, int check_cache)
629 {
630 	const struct got_error *err = NULL;
631 	struct got_packidx *packidx = NULL;
632 	int idx;
633 	char *path_packfile = NULL;
634 	struct got_object *obj = NULL;
635 	int obj_type = GOT_OBJ_TYPE_ANY;
636 
637 	if (check_cache) {
638 		*tag = got_repo_get_cached_tag(repo, id);
639 		if (*tag != NULL) {
640 			(*tag)->refcnt++;
641 			return NULL;
642 		}
643 	} else
644 		*tag = NULL;
645 
646 	err = got_repo_search_packidx(&packidx, &idx, repo, id);
647 	if (err == NULL) {
648 		struct got_pack *pack = NULL;
649 		uint8_t *buf = NULL;
650 		size_t len;
651 
652 		err = got_packidx_get_packfile_path(&path_packfile,
653 		    packidx->path_packidx);
654 		if (err)
655 			return err;
656 
657 		pack = got_repo_get_cached_pack(repo, path_packfile);
658 		if (pack == NULL) {
659 			err = got_repo_cache_pack(&pack, repo, path_packfile,
660 			    packidx);
661 			if (err)
662 				goto done;
663 		}
664 
665 		/* Beware of "lightweight" tags: Check object type first. */
666 		err = got_packfile_open_object(&obj, pack, packidx, idx, id);
667 		if (err)
668 			goto done;
669 		obj_type = obj->type;
670 		if (obj_type != GOT_OBJ_TYPE_TAG) {
671 			err = got_error(GOT_ERR_OBJ_TYPE);
672 			got_object_close(obj);
673 			goto done;
674 		}
675 		err = got_packfile_extract_object_to_mem(&buf, &len,
676 		    obj, pack);
677 		got_object_close(obj);
678 		if (err)
679 			goto done;
680 		err = got_object_parse_tag(tag, buf, len);
681 		free(buf);
682 	} else if (err->code == GOT_ERR_NO_OBJ) {
683 		int fd;
684 
685 		err = got_object_open_loose_fd(&fd, id, repo);
686 		if (err)
687 			return err;
688 		err = got_object_read_header(&obj, fd);
689 		if (close(fd) == -1 && err == NULL)
690 			err = got_error_from_errno("close");
691 		if (err)
692 			return err;
693 		obj_type = obj->type;
694 		got_object_close(obj);
695 		if (obj_type != GOT_OBJ_TYPE_TAG)
696 			return got_error(GOT_ERR_OBJ_TYPE);
697 
698 		err = got_object_open_loose_fd(&fd, id, repo);
699 		if (err)
700 			return err;
701 		err = got_object_read_tag(tag, fd, id, 0);
702 		if (close(fd) == -1 && err == NULL)
703 			err = got_error_from_errno("close");
704 		if (err)
705 			return err;
706 	}
707 
708 	if (err == NULL) {
709 		(*tag)->refcnt++;
710 		err = got_repo_cache_tag(repo, id, *tag);
711 		if (err) {
712 			if (err->code == GOT_ERR_OBJ_EXISTS ||
713 			    err->code == GOT_ERR_OBJ_TOO_LARGE)
714 				err = NULL;
715 		}
716 	}
717 done:
718 	free(path_packfile);
719 	return err;
720 }
721 
722 const struct got_error *
723 got_object_open_as_tag(struct got_tag_object **tag,
724     struct got_repository *repo, struct got_object_id *id)
725 {
726 	*tag = got_repo_get_cached_tag(repo, id);
727 	if (*tag != NULL) {
728 		(*tag)->refcnt++;
729 		return NULL;
730 	}
731 
732 	return open_tag(tag, repo, id, 0);
733 }
734 
735 const struct got_error *
736 got_object_tag_open(struct got_tag_object **tag,
737     struct got_repository *repo, struct got_object *obj)
738 {
739 	return open_tag(tag, repo, got_object_get_id(obj), 1);
740 }