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Blob

Date:: Sun Feb 12 14:10:00 2023 UTC
Message:: bump hash size and add algo field to got_object_id; fix a few places
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/tree.h>
21 #include <sys/uio.h>
22 #include <sys/mman.h>
23 
24 #include <errno.h>
25 #include <fcntl.h>
26 #include <stdio.h>
27 #include <stdlib.h>
28 #include <string.h>
29 #include <sha1.h>
30 #include <sha2.h>
31 #include <unistd.h>
32 #include <zlib.h>
33 #include <libgen.h>
34 #include <limits.h>
35 #include <imsg.h>
36 
37 #include "got_error.h"
38 #include "got_object.h"
39 #include "got_repository.h"
40 #include "got_opentemp.h"
41 #include "got_path.h"
42 
43 #include "got_lib_hash.h"
44 #include "got_lib_delta.h"
45 #include "got_lib_inflate.h"
46 #include "got_lib_object.h"
47 #include "got_lib_object_idcache.h"
48 #include "got_lib_object_cache.h"
49 #include "got_lib_object_parse.h"
50 #include "got_lib_pack.h"
51 #include "got_lib_repository.h"
52 
53 #ifndef MIN
54 #define	MIN(_a,_b) ((_a) < (_b) ? (_a) : (_b))
55 #endif
56 
57 #ifndef nitems
58 #define nitems(_a)	(sizeof((_a)) / sizeof((_a)[0]))
59 #endif
60 
61 struct got_object_id *
62 got_object_get_id(struct got_object *obj)
63 {
64 	return &obj->id;
65 }
66 
67 const struct got_error *
68 got_object_get_id_str(char **outbuf, struct got_object *obj)
69 {
70 	return got_object_id_str(outbuf, &obj->id);
71 }
72 
73 const struct got_error *
74 got_object_get_type(int *type, struct got_repository *repo,
75     struct got_object_id *id)
76 {
77 	const struct got_error *err = NULL;
78 	struct got_object *obj;
79 
80 	err = got_object_open(&obj, repo, id);
81 	if (err)
82 		return err;
83 
84 	switch (obj->type) {
85 	case GOT_OBJ_TYPE_COMMIT:
86 	case GOT_OBJ_TYPE_TREE:
87 	case GOT_OBJ_TYPE_BLOB:
88 	case GOT_OBJ_TYPE_TAG:
89 		*type = obj->type;
90 		break;
91 	default:
92 		err = got_error(GOT_ERR_OBJ_TYPE);
93 		break;
94 	}
95 
96 	got_object_close(obj);
97 	return err;
98 }
99 
100 const struct got_error *
101 got_object_get_path(char **path, struct got_object_id *id,
102     struct got_repository *repo)
103 {
104 	const struct got_error *err = NULL;
105 	char *hex = NULL;
106 	char *path_objects;
107 
108 	*path = NULL;
109 
110 	path_objects = got_repo_get_path_objects(repo);
111 	if (path_objects == NULL)
112 		return got_error_from_errno("got_repo_get_path_objects");
113 
114 	err = got_object_id_str(&hex, id);
115 	if (err)
116 		goto done;
117 
118 	if (asprintf(path, "%s/%.2x/%s", path_objects,
119 	    id->hash[0], hex + 2) == -1)
120 		err = got_error_from_errno("asprintf");
121 
122 done:
123 	free(hex);
124 	free(path_objects);
125 	return err;
126 }
127 
128 const struct got_error *
129 got_object_open_loose_fd(int *fd, struct got_object_id *id,
130     struct got_repository *repo)
131 {
132 	const struct got_error *err = NULL;
133 	char *path;
134 
135 	err = got_object_get_path(&path, id, repo);
136 	if (err)
137 		return err;
138 	*fd = open(path, O_RDONLY | O_NOFOLLOW | O_CLOEXEC);
139 	if (*fd == -1) {
140 		err = got_error_from_errno2("open", path);
141 		goto done;
142 	}
143 done:
144 	free(path);
145 	return err;
146 }
147 
148 const struct got_error *
149 got_object_open_by_id_str(struct got_object **obj, struct got_repository *repo,
150     const char *id_str)
151 {
152 	struct got_object_id id;
153 
154 	memset(&id, 0, sizeof(id));
155 	id.algo = got_repo_get_object_format(repo);
156 	if (!got_parse_hash_digest(id.hash, id_str, id.algo))
157 		return got_error_path(id_str, GOT_ERR_BAD_OBJ_ID_STR);
158 
159 	return got_object_open(obj, repo, &id);
160 }
161 
162 const struct got_error *
163 got_object_resolve_id_str(struct got_object_id **id,
164     struct got_repository *repo, const char *id_str)
165 {
166 	const struct got_error *err = NULL;
167 	struct got_object *obj;
168 
169 	err = got_object_open_by_id_str(&obj, repo, id_str);
170 	if (err)
171 		return err;
172 
173 	*id = got_object_id_dup(got_object_get_id(obj));
174 	got_object_close(obj);
175 	if (*id == NULL)
176 		return got_error_from_errno("got_object_id_dup");
177 
178 	return NULL;
179 }
180 
181 const struct got_error *
182 got_object_qid_alloc(struct got_object_qid **qid, struct got_object_id *id)
183 {
184 	*qid = calloc(1, sizeof(**qid));
185 	if (*qid == NULL)
186 		return got_error_from_errno("calloc");
187 
188 	memcpy(&(*qid)->id, id, sizeof((*qid)->id));
189 	return NULL;
190 }
191 
192 const struct got_error *
193 got_object_id_queue_copy(const struct got_object_id_queue *src,
194     struct got_object_id_queue *dest)
195 {
196 	const struct got_error *err;
197 	struct got_object_qid *qid;
198 
199 	STAILQ_FOREACH(qid, src, entry) {
200 		struct got_object_qid *new;
201 		/*
202 		 * Deep-copy the object ID only. Let the caller deal
203 		 * with setting up the new->data pointer if needed.
204 		 */
205 		err = got_object_qid_alloc(&new, &qid->id);
206 		if (err) {
207 			got_object_id_queue_free(dest);
208 			return err;
209 		}
210 		STAILQ_INSERT_TAIL(dest, new, entry);
211 	}
212 
213 	return NULL;
214 }
215 
216 int
217 got_object_tree_get_nentries(struct got_tree_object *tree)
218 {
219 	return tree->nentries;
220 }
221 
222 struct got_tree_entry *
223 got_object_tree_get_first_entry(struct got_tree_object *tree)
224 {
225 	return got_object_tree_get_entry(tree, 0);
226 }
227 
228 struct got_tree_entry *
229 got_object_tree_get_last_entry(struct got_tree_object *tree)
230 {
231 	return got_object_tree_get_entry(tree, tree->nentries - 1);
232 }
233 
234 struct got_tree_entry *
235 got_object_tree_get_entry(struct got_tree_object *tree, int i)
236 {
237 	if (i < 0 || i >= tree->nentries)
238 		return NULL;
239 	return &tree->entries[i];
240 }
241 
242 mode_t
243 got_tree_entry_get_mode(struct got_tree_entry *te)
244 {
245 	return te->mode;
246 }
247 
248 const char *
249 got_tree_entry_get_name(struct got_tree_entry *te)
250 {
251 	return &te->name[0];
252 }
253 
254 struct got_object_id *
255 got_tree_entry_get_id(struct got_tree_entry *te)
256 {
257 	return &te->id;
258 }
259 
260 const struct got_error *
261 got_object_blob_read_to_str(char **s, struct got_blob_object *blob)
262 {
263 	const struct got_error *err = NULL;
264 	size_t len, totlen, hdrlen, offset;
265 
266 	*s = NULL;
267 
268 	hdrlen = got_object_blob_get_hdrlen(blob);
269 	totlen = 0;
270 	offset = 0;
271 	do {
272 		char *p;
273 
274 		err = got_object_blob_read_block(&len, blob);
275 		if (err)
276 			return err;
277 
278 		if (len == 0)
279 			break;
280 
281 		totlen += len - hdrlen;
282 		p = realloc(*s, totlen + 1);
283 		if (p == NULL) {
284 			err = got_error_from_errno("realloc");
285 			free(*s);
286 			*s = NULL;
287 			return err;
288 		}
289 		*s = p;
290 		/* Skip blob object header first time around. */
291 		memcpy(*s + offset,
292 		    got_object_blob_get_read_buf(blob) + hdrlen, len - hdrlen);
293 		hdrlen = 0;
294 		offset = totlen;
295 	} while (len > 0);
296 
297 	(*s)[totlen] = '\0';
298 	return NULL;
299 }
300 
301 const struct got_error *
302 got_tree_entry_get_symlink_target(char **link_target, struct got_tree_entry *te,
303     struct got_repository *repo)
304 {
305 	const struct got_error *err = NULL;
306 	struct got_blob_object *blob = NULL;
307 	int fd = -1;
308 
309 	*link_target = NULL;
310 
311 	if (!got_object_tree_entry_is_symlink(te))
312 		return got_error(GOT_ERR_TREE_ENTRY_TYPE);
313 
314 	fd = got_opentempfd();
315 	if (fd == -1) {
316 		err = got_error_from_errno("got_opentempfd");
317 		goto done;
318 	}
319 
320 	err = got_object_open_as_blob(&blob, repo,
321 	    got_tree_entry_get_id(te), PATH_MAX, fd);
322 	if (err)
323 		goto done;
324 
325 	err = got_object_blob_read_to_str(link_target, blob);
326 done:
327 	if (fd != -1 && close(fd) == -1 && err == NULL)
328 		err = got_error_from_errno("close");
329 	if (blob)
330 		got_object_blob_close(blob);
331 	if (err) {
332 		free(*link_target);
333 		*link_target = NULL;
334 	}
335 	return err;
336 }
337 
338 int
339 got_tree_entry_get_index(struct got_tree_entry *te)
340 {
341 	return te->idx;
342 }
343 
344 struct got_tree_entry *
345 got_tree_entry_get_next(struct got_tree_object *tree,
346     struct got_tree_entry *te)
347 {
348 	return got_object_tree_get_entry(tree, te->idx + 1);
349 }
350 
351 struct got_tree_entry *
352 got_tree_entry_get_prev(struct got_tree_object *tree,
353     struct got_tree_entry *te)
354 {
355 	return got_object_tree_get_entry(tree, te->idx - 1);
356 }
357 
358 const struct got_error *
359 got_object_blob_close(struct got_blob_object *blob)
360 {
361 	const struct got_error *err = NULL;
362 	free(blob->read_buf);
363 	if (blob->f && fclose(blob->f) == EOF)
364 		err = got_error_from_errno("fclose");
365 	free(blob->data);
366 	free(blob);
367 	return err;
368 }
369 
370 void
371 got_object_blob_rewind(struct got_blob_object *blob)
372 {
373 	if (blob->f)
374 		rewind(blob->f);
375 }
376 
377 char *
378 got_object_blob_id_str(struct got_blob_object *blob, char *buf, size_t size)
379 {
380 	return got_object_id_hex(&blob->id, buf, size);
381 }
382 
383 size_t
384 got_object_blob_get_hdrlen(struct got_blob_object *blob)
385 {
386 	return blob->hdrlen;
387 }
388 
389 const uint8_t *
390 got_object_blob_get_read_buf(struct got_blob_object *blob)
391 {
392 	return blob->read_buf;
393 }
394 
395 const struct got_error *
396 got_object_blob_read_block(size_t *outlenp, struct got_blob_object *blob)
397 {
398 	size_t n;
399 
400 	n = fread(blob->read_buf, 1, blob->blocksize, blob->f);
401 	if (n == 0 && ferror(blob->f))
402 		return got_ferror(blob->f, GOT_ERR_IO);
403 	*outlenp = n;
404 	return NULL;
405 }
406 
407 const struct got_error *
408 got_object_blob_is_binary(int *binary, struct got_blob_object *blob)
409 {
410 	const struct got_error *err;
411 	size_t hdrlen, len;
412 
413 	*binary = 0;
414 	hdrlen = got_object_blob_get_hdrlen(blob);
415 
416 	if (fseeko(blob->f, hdrlen, SEEK_SET) == -1)
417 		return got_error_from_errno("fseeko");
418 
419 	err = got_object_blob_read_block(&len, blob);
420 	if (err)
421 		return err;
422 
423 	*binary = memchr(blob->read_buf, '\0', len) != NULL;
424 
425 	if (fseeko(blob->f, hdrlen, SEEK_SET) == -1)
426 		return got_error_from_errno("fseeko");
427 	return NULL;
428 }
429 
430 const struct got_error *
431 got_object_blob_getline(char **line, ssize_t *linelen, size_t *linesize,
432     struct got_blob_object *blob)
433 {
434 	*linelen = getline(line, linesize, blob->f);
435 	if (*linelen == -1 && !feof(blob->f))
436 		return got_error_from_errno("getline");
437 	return NULL;
438 }
439 
440 const struct got_error *
441 got_object_blob_dump_to_file(off_t *filesize, int *nlines,
442     off_t **line_offsets, FILE *outfile, struct got_blob_object *blob)
443 {
444 	const struct got_error *err = NULL;
445 	size_t n, len, hdrlen;
446 	const uint8_t *buf;
447 	int i;
448 	const int alloc_chunksz = 512;
449 	size_t nalloc = 0;
450 	off_t off = 0, total_len = 0;
451 
452 	if (line_offsets)
453 		*line_offsets = NULL;
454 	if (filesize)
455 		*filesize = 0;
456 	if (nlines)
457 		*nlines = 0;
458 
459 	hdrlen = got_object_blob_get_hdrlen(blob);
460 	do {
461 		err = got_object_blob_read_block(&len, blob);
462 		if (err)
463 			return err;
464 		if (len == 0)
465 			break;
466 		buf = got_object_blob_get_read_buf(blob);
467 		i = hdrlen;
468 		if (nlines) {
469 			if (line_offsets && *line_offsets == NULL) {
470 				/* Have some data but perhaps no '\n'. */
471 				*nlines = 1;
472 				nalloc = alloc_chunksz;
473 				*line_offsets = calloc(nalloc,
474 				    sizeof(**line_offsets));
475 				if (*line_offsets == NULL)
476 					return got_error_from_errno("calloc");
477 
478 				/* Skip forward over end of first line. */
479 				while (i < len) {
480 					if (buf[i] == '\n')
481 						break;
482 					i++;
483 				}
484 			}
485 			/* Scan '\n' offsets in remaining chunk of data. */
486 			while (i < len) {
487 				if (buf[i] != '\n') {
488 					i++;
489 					continue;
490 				}
491 				(*nlines)++;
492 				if (line_offsets && nalloc < *nlines) {
493 					size_t n = *nlines + alloc_chunksz;
494 					off_t *o = recallocarray(*line_offsets,
495 					    nalloc, n, sizeof(**line_offsets));
496 					if (o == NULL) {
497 						free(*line_offsets);
498 						*line_offsets = NULL;
499 						return got_error_from_errno(
500 						    "recallocarray");
501 					}
502 					*line_offsets = o;
503 					nalloc = n;
504 				}
505 				if (line_offsets) {
506 					off = total_len + i - hdrlen + 1;
507 					(*line_offsets)[*nlines - 1] = off;
508 				}
509 				i++;
510 			}
511 		}
512 		/* Skip blob object header first time around. */
513 		n = fwrite(buf + hdrlen, 1, len - hdrlen, outfile);
514 		if (n != len - hdrlen)
515 			return got_ferror(outfile, GOT_ERR_IO);
516 		total_len += len - hdrlen;
517 		hdrlen = 0;
518 	} while (len != 0);
519 
520 	if (fflush(outfile) != 0)
521 		return got_error_from_errno("fflush");
522 	rewind(outfile);
523 
524 	if (filesize)
525 		*filesize = total_len;
526 
527 	return NULL;
528 }
529 
530 const char *
531 got_object_tag_get_name(struct got_tag_object *tag)
532 {
533 	return tag->tag;
534 }
535 
536 int
537 got_object_tag_get_object_type(struct got_tag_object *tag)
538 {
539 	return tag->obj_type;
540 }
541 
542 struct got_object_id *
543 got_object_tag_get_object_id(struct got_tag_object *tag)
544 {
545 	return &tag->id;
546 }
547 
548 time_t
549 got_object_tag_get_tagger_time(struct got_tag_object *tag)
550 {
551 	return tag->tagger_time;
552 }
553 
554 time_t
555 got_object_tag_get_tagger_gmtoff(struct got_tag_object *tag)
556 {
557 	return tag->tagger_gmtoff;
558 }
559 
560 const char *
561 got_object_tag_get_tagger(struct got_tag_object *tag)
562 {
563 	return tag->tagger;
564 }
565 
566 const char *
567 got_object_tag_get_message(struct got_tag_object *tag)
568 {
569 	return tag->tagmsg;
570 }
571 
572 static struct got_tree_entry *
573 find_entry_by_name(struct got_tree_object *tree, const char *name, size_t len)
574 {
575 	int i;
576 
577 	/* Note that tree entries are sorted in strncmp() order. */
578 	for (i = 0; i < tree->nentries; i++) {
579 		struct got_tree_entry *te = &tree->entries[i];
580 		int cmp = strncmp(te->name, name, len);
581 		if (cmp < 0)
582 			continue;
583 		if (cmp > 0)
584 			break;
585 		if (te->name[len] == '\0')
586 			return te;
587 	}
588 	return NULL;
589 }
590 
591 struct got_tree_entry *
592 got_object_tree_find_entry(struct got_tree_object *tree, const char *name)
593 {
594 	return find_entry_by_name(tree, name, strlen(name));
595 }
596 
597 const struct got_error *
598 got_object_tree_find_path(struct got_object_id **id, mode_t *mode,
599     struct got_repository *repo, struct got_tree_object *tree,
600     const char *path)
601 {
602 	const struct got_error *err = NULL;
603 	struct got_tree_object *subtree = NULL;
604 	struct got_tree_entry *te = NULL;
605 	const char *seg, *s;
606 	size_t seglen;
607 
608 	*id = NULL;
609 
610 	s = path;
611 	while (s[0] == '/')
612 		s++;
613 	seg = s;
614 	seglen = 0;
615 	subtree = tree;
616 	while (*s) {
617 		struct got_tree_object *next_tree;
618 
619 		if (*s != '/') {
620 			s++;
621 			seglen++;
622 			if (*s)
623 				continue;
624 		}
625 
626 		te = find_entry_by_name(subtree, seg, seglen);
627 		if (te == NULL) {
628 			err = got_error_path(path, GOT_ERR_NO_TREE_ENTRY);
629 			goto done;
630 		}
631 
632 		if (*s == '\0')
633 			break;
634 
635 		seg = s + 1;
636 		seglen = 0;
637 		s++;
638 		if (*s) {
639 			err = got_object_open_as_tree(&next_tree, repo,
640 			    &te->id);
641 			te = NULL;
642 			if (err)
643 				goto done;
644 			if (subtree != tree)
645 				got_object_tree_close(subtree);
646 			subtree = next_tree;
647 		}
648 	}
649 
650 	if (te) {
651 		*id = got_object_id_dup(&te->id);
652 		if (*id == NULL)
653 			return got_error_from_errno("got_object_id_dup");
654 		if (mode)
655 			*mode = te->mode;
656 	} else
657 		err = got_error_path(path, GOT_ERR_NO_TREE_ENTRY);
658 done:
659 	if (subtree && subtree != tree)
660 		got_object_tree_close(subtree);
661 	return err;
662 }
663 
664 const struct got_error *
665 got_object_id_by_path(struct got_object_id **id, struct got_repository *repo,
666     struct got_commit_object *commit, const char *path)
667 {
668 	const struct got_error *err = NULL;
669 	struct got_tree_object *tree = NULL;
670 
671 	*id = NULL;
672 
673 	/* Handle opening of root of commit's tree. */
674 	if (got_path_is_root_dir(path)) {
675 		*id = got_object_id_dup(commit->tree_id);
676 		if (*id == NULL)
677 			err = got_error_from_errno("got_object_id_dup");
678 	} else {
679 		err = got_object_open_as_tree(&tree, repo, commit->tree_id);
680 		if (err)
681 			goto done;
682 		err = got_object_tree_find_path(id, NULL, repo, tree, path);
683 	}
684 done:
685 	if (tree)
686 		got_object_tree_close(tree);
687 	return err;
688 }
689 
690 /*
691  * Normalize file mode bits to avoid false positive tree entry differences
692  * in case tree entries have unexpected mode bits set.
693  */
694 static mode_t
695 normalize_mode_for_comparison(mode_t mode)
696 {
697 	/*
698 	 * For directories, the only relevant bit is the IFDIR bit.
699 	 * This allows us to detect paths changing from a directory
700 	 * to a file and vice versa.
701 	 */
702 	if (S_ISDIR(mode))
703 		return mode & S_IFDIR;
704 
705 	/*
706 	 * For symlinks, the only relevant bit is the IFLNK bit.
707 	 * This allows us to detect paths changing from a symlinks
708 	 * to a file or directory and vice versa.
709 	 */
710 	if (S_ISLNK(mode))
711 		return mode & S_IFLNK;
712 
713 	/* For files, the only change we care about is the executable bit. */
714 	return mode & S_IXUSR;
715 }
716 
717 const struct got_error *
718 got_object_tree_path_changed(int *changed,
719     struct got_tree_object *tree01, struct got_tree_object *tree02,
720     const char *path, struct got_repository *repo)
721 {
722 	const struct got_error *err = NULL;
723 	struct got_tree_object *tree1 = NULL, *tree2 = NULL;
724 	struct got_tree_entry *te1 = NULL, *te2 = NULL;
725 	const char *seg, *s;
726 	size_t seglen;
727 
728 	*changed = 0;
729 
730 	/* We not do support comparing the root path. */
731 	if (got_path_is_root_dir(path))
732 		return got_error_path(path, GOT_ERR_BAD_PATH);
733 
734 	tree1 = tree01;
735 	tree2 = tree02;
736 	s = path;
737 	while (*s == '/')
738 		s++;
739 	seg = s;
740 	seglen = 0;
741 	while (*s) {
742 		struct got_tree_object *next_tree1, *next_tree2;
743 		mode_t mode1, mode2;
744 
745 		if (*s != '/') {
746 			s++;
747 			seglen++;
748 			if (*s)
749 				continue;
750 		}
751 
752 		te1 = find_entry_by_name(tree1, seg, seglen);
753 		if (te1 == NULL) {
754 			err = got_error(GOT_ERR_NO_OBJ);
755 			goto done;
756 		}
757 
758 		if (tree2)
759 			te2 = find_entry_by_name(tree2, seg, seglen);
760 
761 		if (te2) {
762 			mode1 = normalize_mode_for_comparison(te1->mode);
763 			mode2 = normalize_mode_for_comparison(te2->mode);
764 			if (mode1 != mode2) {
765 				*changed = 1;
766 				goto done;
767 			}
768 
769 			if (got_object_id_cmp(&te1->id, &te2->id) == 0) {
770 				*changed = 0;
771 				goto done;
772 			}
773 		}
774 
775 		if (*s == '\0') { /* final path element */
776 			*changed = 1;
777 			goto done;
778 		}
779 
780 		seg = s + 1;
781 		s++;
782 		seglen = 0;
783 		if (*s) {
784 			err = got_object_open_as_tree(&next_tree1, repo,
785 			    &te1->id);
786 			te1 = NULL;
787 			if (err)
788 				goto done;
789 			if (tree1 != tree01)
790 				got_object_tree_close(tree1);
791 			tree1 = next_tree1;
792 
793 			if (te2) {
794 				err = got_object_open_as_tree(&next_tree2, repo,
795 				    &te2->id);
796 				te2 = NULL;
797 				if (err)
798 					goto done;
799 				if (tree2 != tree02)
800 					got_object_tree_close(tree2);
801 				tree2 = next_tree2;
802 			} else if (tree2) {
803 				if (tree2 != tree02)
804 					got_object_tree_close(tree2);
805 				tree2 = NULL;
806 			}
807 		}
808 	}
809 done:
810 	if (tree1 && tree1 != tree01)
811 		got_object_tree_close(tree1);
812 	if (tree2 && tree2 != tree02)
813 		got_object_tree_close(tree2);
814 	return err;
815 }
816 
817 const struct got_error *
818 got_object_tree_entry_dup(struct got_tree_entry **new_te,
819     struct got_tree_entry *te)
820 {
821 	const struct got_error *err = NULL;
822 
823 	*new_te = calloc(1, sizeof(**new_te));
824 	if (*new_te == NULL)
825 		return got_error_from_errno("calloc");
826 
827 	(*new_te)->mode = te->mode;
828 	memcpy((*new_te)->name, te->name, sizeof((*new_te)->name));
829 	memcpy(&(*new_te)->id, &te->id, sizeof((*new_te)->id));
830 	return err;
831 }
832 
833 int
834 got_object_tree_entry_is_submodule(struct got_tree_entry *te)
835 {
836 	return (te->mode & S_IFMT) == (S_IFDIR | S_IFLNK);
837 }
838 
839 int
840 got_object_tree_entry_is_symlink(struct got_tree_entry *te)
841 {
842 	/* S_IFDIR check avoids confusing symlinks with submodules. */
843 	return ((te->mode & (S_IFDIR | S_IFLNK)) == S_IFLNK);
844 }
845 
846 static const struct got_error *
847 resolve_symlink(char **link_target, const char *path,
848     struct got_commit_object *commit, struct got_repository *repo)
849 {
850 	const struct got_error *err = NULL;
851 	char buf[PATH_MAX];
852 	char *name, *parent_path = NULL;
853 	struct got_object_id *tree_obj_id = NULL;
854 	struct got_tree_object *tree = NULL;
855 	struct got_tree_entry *te = NULL;
856 
857 	*link_target = NULL;
858 
859 	if (strlcpy(buf, path, sizeof(buf)) >= sizeof(buf))
860 		return got_error(GOT_ERR_NO_SPACE);
861 
862 	name = basename(buf);
863 	if (name == NULL)
864 		return got_error_from_errno2("basename", path);
865 
866 	err = got_path_dirname(&parent_path, path);
867 	if (err)
868 		return err;
869 
870 	err = got_object_id_by_path(&tree_obj_id, repo, commit,
871 	    parent_path);
872 	if (err) {
873 		if (err->code == GOT_ERR_NO_TREE_ENTRY) {
874 			/* Display the complete path in error message. */
875 			err = got_error_path(path, err->code);
876 		}
877 		goto done;
878 	}
879 
880 	err = got_object_open_as_tree(&tree, repo, tree_obj_id);
881 	if (err)
882 		goto done;
883 
884 	te = got_object_tree_find_entry(tree, name);
885 	if (te == NULL) {
886 		err = got_error_path(path, GOT_ERR_NO_TREE_ENTRY);
887 		goto done;
888 	}
889 
890 	if (got_object_tree_entry_is_symlink(te)) {
891 		err = got_tree_entry_get_symlink_target(link_target, te, repo);
892 		if (err)
893 			goto done;
894 		if (!got_path_is_absolute(*link_target)) {
895 			char *abspath;
896 			if (asprintf(&abspath, "%s/%s", parent_path,
897 			    *link_target) == -1) {
898 				err = got_error_from_errno("asprintf");
899 				goto done;
900 			}
901 			free(*link_target);
902 			*link_target = malloc(PATH_MAX);
903 			if (*link_target == NULL) {
904 				err = got_error_from_errno("malloc");
905 				goto done;
906 			}
907 			err = got_canonpath(abspath, *link_target, PATH_MAX);
908 			free(abspath);
909 			if (err)
910 				goto done;
911 		}
912 	}
913 done:
914 	free(parent_path);
915 	free(tree_obj_id);
916 	if (tree)
917 		got_object_tree_close(tree);
918 	if (err) {
919 		free(*link_target);
920 		*link_target = NULL;
921 	}
922 	return err;
923 }
924 
925 const struct got_error *
926 got_object_resolve_symlinks(char **link_target, const char *path,
927     struct got_commit_object *commit, struct got_repository *repo)
928 {
929 	const struct got_error *err = NULL;
930 	char *next_target = NULL;
931 	int max_recursion = 40; /* matches Git */
932 
933 	*link_target = NULL;
934 
935 	do {
936 		err = resolve_symlink(&next_target,
937 		    *link_target ? *link_target : path, commit, repo);
938 		if (err)
939 			break;
940 		if (next_target) {
941 			free(*link_target);
942 			if (--max_recursion == 0) {
943 				err = got_error_path(path, GOT_ERR_RECURSION);
944 				*link_target = NULL;
945 				break;
946 			}
947 			*link_target = next_target;
948 		}
949 	} while (next_target);
950 
951 	return err;
952 }
953 
954 void
955 got_object_commit_retain(struct got_commit_object *commit)
956 {
957 	commit->refcnt++;
958 }
959 
960 const struct got_error *
961 got_object_raw_alloc(struct got_raw_object **obj, uint8_t *outbuf, int *outfd,
962     size_t max_in_mem_size, size_t hdrlen, off_t size)
963 {
964 	const struct got_error *err = NULL;
965 	off_t tot;
966 
967 	tot = hdrlen + size;
968 
969 	*obj = calloc(1, sizeof(**obj));
970 	if (*obj == NULL) {
971 		err = got_error_from_errno("calloc");
972 		goto done;
973 	}
974 	(*obj)->fd = -1;
975 	(*obj)->tempfile_idx = -1;
976 
977 	if (outbuf) {
978 		(*obj)->data = outbuf;
979 	} else {
980 		struct stat sb;
981 		if (fstat(*outfd, &sb) == -1) {
982 			err = got_error_from_errno("fstat");
983 			goto done;
984 		}
985 
986 		if (sb.st_size != tot) {
987 			err = got_error_msg(GOT_ERR_BAD_OBJ_HDR,
988 			    "raw object has unexpected size");
989 			goto done;
990 		}
991 #ifndef GOT_PACK_NO_MMAP
992 		if (tot > 0 && tot <= max_in_mem_size) {
993 			(*obj)->data = mmap(NULL, tot, PROT_READ,
994 			    MAP_PRIVATE, *outfd, 0);
995 			if ((*obj)->data == MAP_FAILED) {
996 				if (errno != ENOMEM) {
997 					err = got_error_from_errno("mmap");
998 					goto done;
999 				}
1000 				(*obj)->data = NULL;
1001 			} else {
1002 				(*obj)->fd = *outfd;
1003 				*outfd = -1;
1004 			}
1005 		}
1006 #endif
1007 		if (*outfd != -1) {
1008 			(*obj)->f = fdopen(*outfd, "r");
1009 			if ((*obj)->f == NULL) {
1010 				err = got_error_from_errno("fdopen");
1011 				goto done;
1012 			}
1013 			*outfd = -1;
1014 		}
1015 	}
1016 	(*obj)->hdrlen = hdrlen;
1017 	(*obj)->size = size;
1018 done:
1019 	if (err) {
1020 		if (*obj) {
1021 			got_object_raw_close(*obj);
1022 			*obj = NULL;
1023 		}
1024 	} else
1025 		(*obj)->refcnt++;
1026 	return err;
1027 }