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Date:: Fri Jan 22 11:04:47 2021 UTC
Message:: make fclose(3) failure checks consistent; check 'fclose() == EOF' everywhere ok millert, naddy
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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/queue.h>
19 #include <sys/stat.h>
20 
21 #include <errno.h>
22 #include <ctype.h>
23 #include <dirent.h>
24 #include <limits.h>
25 #include <sha1.h>
26 #include <stdio.h>
27 #include <stdlib.h>
28 #include <string.h>
29 #include <unistd.h>
30 #include <util.h>
31 #include <zlib.h>
32 #include <time.h>
33 #include <libgen.h>
34 
35 #include "got_error.h"
36 #include "got_object.h"
37 #include "got_repository.h"
38 #include "got_reference.h"
39 #include "got_opentemp.h"
40 #include "got_path.h"
41 
42 #include "got_lib_sha1.h"
43 #include "got_lib_delta.h"
44 #include "got_lib_inflate.h"
45 #include "got_lib_object.h"
46 #include "got_lib_object_idset.h"
47 #include "got_lib_lockfile.h"
48 
49 #ifndef nitems
50 #define nitems(_a) (sizeof(_a) / sizeof((_a)[0]))
51 #endif
52 
53 #define GOT_REF_HEADS	"heads"
54 #define GOT_REF_TAGS	"tags"
55 #define GOT_REF_REMOTES	"remotes"
56 
57 /*
58  * We do not resolve tags yet, and don't yet care about sorting refs either,
59  * so packed-refs files we write contain a minimal header which disables all
60  * packed-refs "traits" supported by Git.
61  */
62 #define GOT_PACKED_REFS_HEADER	"# pack-refs with:"
63 
64 /* A symbolic reference. */
65 struct got_symref {
66 	char *name;
67 	char *ref;
68 };
69 
70 #define GOT_REF_RECURSE_MAX	20
71 
72 /* A non-symbolic reference (there is no better designation). */
73 struct got_ref {
74 	char *name;
75 	u_int8_t sha1[SHA1_DIGEST_LENGTH];
76 };
77 
78 /* A reference which points to an arbitrary object. */
79 struct got_reference {
80 	unsigned int flags;
81 #define GOT_REF_IS_SYMBOLIC	0x01
82 #define GOT_REF_IS_PACKED	0x02
83 
84 	union {
85 		struct got_ref ref;
86 		struct got_symref symref;
87 	} ref;
88 
89 	struct got_lockfile *lf;
90 };
91 
92 static const struct got_error *
93 alloc_ref(struct got_reference **ref, const char *name,
94     struct got_object_id *id, int flags)
95 {
96 	const struct got_error *err = NULL;
97 
98 	*ref = calloc(1, sizeof(**ref));
99 	if (*ref == NULL)
100 		return got_error_from_errno("calloc");
101 
102 	memcpy((*ref)->ref.ref.sha1, id->sha1, sizeof((*ref)->ref.ref.sha1));
103 	(*ref)->flags = flags;
104 	(*ref)->ref.ref.name = strdup(name);
105 	if ((*ref)->ref.ref.name == NULL) {
106 		err = got_error_from_errno("strdup");
107 		got_ref_close(*ref);
108 		*ref = NULL;
109 	}
110 	return err;
111 }
112 
113 static const struct got_error *
114 alloc_symref(struct got_reference **ref, const char *name,
115     const char *target_ref, int flags)
116 {
117 	const struct got_error *err = NULL;
118 
119 	*ref = calloc(1, sizeof(**ref));
120 	if (*ref == NULL)
121 		return got_error_from_errno("calloc");
122 
123 	(*ref)->flags = GOT_REF_IS_SYMBOLIC | flags;
124 	(*ref)->ref.symref.name = strdup(name);
125 	if ((*ref)->ref.symref.name == NULL) {
126 		err = got_error_from_errno("strdup");
127 		got_ref_close(*ref);
128 		*ref = NULL;
129 		return err;
130 	}
131 	(*ref)->ref.symref.ref = strdup(target_ref);
132 	if ((*ref)->ref.symref.ref == NULL) {
133 		err = got_error_from_errno("strdup");
134 		got_ref_close(*ref);
135 		*ref = NULL;
136 	}
137 	return err;
138 }
139 
140 static const struct got_error *
141 parse_symref(struct got_reference **ref, const char *name, const char *line)
142 {
143 	if (line[0] == '\0')
144 		return got_error(GOT_ERR_BAD_REF_DATA);
145 
146 	return alloc_symref(ref, name, line, 0);
147 }
148 
149 static const struct got_error *
150 parse_ref_line(struct got_reference **ref, const char *name, const char *line)
151 {
152 	struct got_object_id id;
153 
154 	if (strncmp(line, "ref: ", 5) == 0) {
155 		line += 5;
156 		return parse_symref(ref, name, line);
157 	}
158 
159 	if (!got_parse_sha1_digest(id.sha1, line))
160 		return got_error(GOT_ERR_BAD_REF_DATA);
161 
162 	return alloc_ref(ref, name, &id, 0);
163 }
164 
165 static const struct got_error *
166 parse_ref_file(struct got_reference **ref, const char *name,
167     const char *absname, const char *abspath, int lock)
168 {
169 	const struct got_error *err = NULL;
170 	FILE *f;
171 	char *line = NULL;
172 	size_t linesize = 0;
173 	ssize_t linelen;
174 	struct got_lockfile *lf = NULL;
175 
176 	if (lock) {
177 		err = got_lockfile_lock(&lf, abspath);
178 		if (err) {
179 			if (err->code == GOT_ERR_ERRNO && errno == ENOENT)
180 				err = got_error_not_ref(name);
181 			return err;
182 		}
183 	}
184 
185 	f = fopen(abspath, "rb");
186 	if (f == NULL) {
187 		if (errno != ENOTDIR && errno != ENOENT)
188 			err = got_error_from_errno2("fopen", abspath);
189 		else
190 			err = got_error_not_ref(name);
191 		if (lock)
192 			got_lockfile_unlock(lf);
193 		return err;
194 	}
195 
196 	linelen = getline(&line, &linesize, f);
197 	if (linelen == -1) {
198 		if (feof(f))
199 			err = NULL; /* ignore empty files (could be locks) */
200 		else {
201 			if (errno == EISDIR)
202 				err = got_error(GOT_ERR_NOT_REF);
203 			else if (ferror(f))
204 				err = got_ferror(f, GOT_ERR_IO);
205 			else
206 				err = got_error_from_errno2("getline", abspath);
207 		}
208 		if (lock)
209 			got_lockfile_unlock(lf);
210 		goto done;
211 	}
212 	while (linelen > 0 && line[linelen - 1] == '\n') {
213 		line[linelen - 1] = '\0';
214 		linelen--;
215 	}
216 
217 	err = parse_ref_line(ref, absname, line);
218 	if (lock) {
219 		if (err)
220 			got_lockfile_unlock(lf);
221 		else {
222 			if (*ref)
223 				(*ref)->lf = lf;
224 			else
225 				got_lockfile_unlock(lf);
226 		}
227 	}
228 done:
229 	free(line);
230 	if (fclose(f) == EOF && err == NULL) {
231 		err = got_error_from_errno("fclose");
232 		if (*ref) {
233 			if (lock)
234 				got_ref_unlock(*ref);
235 			got_ref_close(*ref);
236 			*ref = NULL;
237 		}
238 	}
239 	return err;
240 }
241 
242 static int
243 is_well_known_ref(const char *refname)
244 {
245 	return (strcmp(refname, GOT_REF_HEAD) == 0 ||
246 	    strcmp(refname, GOT_REF_ORIG_HEAD) == 0 ||
247 	    strcmp(refname, GOT_REF_MERGE_HEAD) == 0 ||
248 	    strcmp(refname, GOT_REF_FETCH_HEAD) == 0);
249 }
250 
251 static char *
252 get_refs_dir_path(struct got_repository *repo, const char *refname)
253 {
254 	if (is_well_known_ref(refname) || strncmp(refname, "refs/", 5) == 0)
255 		return strdup(got_repo_get_path_git_dir(repo));
256 
257 	return got_repo_get_path_refs(repo);
258 }
259 
260 static int
261 is_valid_ref_name(const char *name)
262 {
263 	const char *s, *seg;
264 	const char forbidden[] = { ' ', '~', '^', ':', '?', '*', '[' , '\\' };
265 	const char *forbidden_seq[] = { "//", "..", "@{" };
266 	const char *lfs = GOT_LOCKFILE_SUFFIX;
267 	const size_t lfs_len = sizeof(GOT_LOCKFILE_SUFFIX) - 1;
268 	size_t i;
269 
270 	if (name[0] == '@' && name[1] == '\0')
271 		return 0;
272 
273 	s = name;
274 	seg = s;
275 	if (seg[0] == '\0' || seg[0] == '.' || seg[0] == '/')
276 		return 0;
277 	while (*s) {
278 		for (i = 0; i < nitems(forbidden); i++) {
279 			if (*s == forbidden[i])
280 				return 0;
281 		}
282 		for (i = 0; i < nitems(forbidden_seq); i++) {
283 			if (s[0] == forbidden_seq[i][0] &&
284 			    s[1] == forbidden_seq[i][1])
285 				return 0;
286 		}
287 		if (iscntrl((unsigned char)s[0]))
288 			return 0;
289 		if (s[0] == '.' && s[1] == '\0')
290 			return 0;
291 		if (*s == '/') {
292 			const char *nextseg = s + 1;
293 			if (nextseg[0] == '\0' || nextseg[0] == '.' ||
294 			    nextseg[0] == '/')
295 				return 0;
296 			if (seg <= s - lfs_len &&
297 			    strncmp(s - lfs_len, lfs, lfs_len) == 0)
298 				return 0;
299 			seg = nextseg;
300 		}
301 		s++;
302 	}
303 
304 	if (seg <= s - lfs_len &&
305 	    strncmp(s - lfs_len, lfs, lfs_len) == 0)
306 		return 0;
307 
308 	return 1;
309 }
310 
311 const struct got_error *
312 got_ref_alloc(struct got_reference **ref, const char *name,
313     struct got_object_id *id)
314 {
315 	if (!is_valid_ref_name(name))
316 		return got_error_path(name, GOT_ERR_BAD_REF_NAME);
317 
318 	return alloc_ref(ref, name, id, 0);
319 }
320 
321 const struct got_error *
322 got_ref_alloc_symref(struct got_reference **ref, const char *name,
323 	struct got_reference *target_ref)
324 {
325 	if (!is_valid_ref_name(name))
326 		return got_error_path(name, GOT_ERR_BAD_REF_NAME);
327 
328 	return alloc_symref(ref, name, got_ref_get_name(target_ref), 0);
329 }
330 
331 static const struct got_error *
332 parse_packed_ref_line(struct got_reference **ref, const char *abs_refname,
333     const char *line)
334 {
335 	struct got_object_id id;
336 	const char *name;
337 
338 	*ref = NULL;
339 
340 	if (line[0] == '#' || line[0] == '^')
341 		return NULL;
342 
343 	if (!got_parse_sha1_digest(id.sha1, line))
344 		return got_error(GOT_ERR_BAD_REF_DATA);
345 
346 	if (abs_refname) {
347 		if (strcmp(line + SHA1_DIGEST_STRING_LENGTH, abs_refname) != 0)
348 			return NULL;
349 		name = abs_refname;
350 	} else
351 		name = line + SHA1_DIGEST_STRING_LENGTH;
352 
353 	return alloc_ref(ref, name, &id, GOT_REF_IS_PACKED);
354 }
355 
356 static const struct got_error *
357 open_packed_ref(struct got_reference **ref, FILE *f, const char **subdirs,
358     int nsubdirs, const char *refname)
359 {
360 	const struct got_error *err = NULL;
361 	char *abs_refname;
362 	char *line = NULL;
363 	size_t linesize = 0;
364 	ssize_t linelen;
365 	int i, ref_is_absolute = (strncmp(refname, "refs/", 5) == 0);
366 
367 	*ref = NULL;
368 
369 	if (ref_is_absolute)
370 		abs_refname = (char *)refname;
371 	do {
372 		linelen = getline(&line, &linesize, f);
373 		if (linelen == -1) {
374 			if (feof(f))
375 				break;
376 			err = got_ferror(f, GOT_ERR_BAD_REF_DATA);
377 			break;
378 		}
379 		if (linelen > 0 && line[linelen - 1] == '\n')
380 			line[linelen - 1] = '\0';
381 		for (i = 0; i < nsubdirs; i++) {
382 			if (!ref_is_absolute &&
383 			    asprintf(&abs_refname, "refs/%s/%s", subdirs[i],
384 			    refname) == -1)
385 				return got_error_from_errno("asprintf");
386 			err = parse_packed_ref_line(ref, abs_refname, line);
387 			if (!ref_is_absolute)
388 				free(abs_refname);
389 			if (err || *ref != NULL)
390 				break;
391 		}
392 		if (err)
393 			break;
394 	} while (*ref == NULL);
395 	free(line);
396 
397 	return err;
398 }
399 
400 static const struct got_error *
401 open_ref(struct got_reference **ref, const char *path_refs, const char *subdir,
402     const char *name, int lock)
403 {
404 	const struct got_error *err = NULL;
405 	char *path = NULL;
406 	char *absname = NULL;
407 	int ref_is_absolute = (strncmp(name, "refs/", 5) == 0);
408 	int ref_is_well_known = (subdir[0] == '\0' && is_well_known_ref(name));
409 
410 	*ref = NULL;
411 
412 	if (ref_is_absolute || ref_is_well_known) {
413 		if (asprintf(&path, "%s/%s", path_refs, name) == -1)
414 			return got_error_from_errno("asprintf");
415 		absname = (char *)name;
416 	} else {
417 		if (asprintf(&path, "%s/%s%s%s", path_refs, subdir,
418 		    subdir[0] ? "/" : "", name) == -1)
419 			return got_error_from_errno("asprintf");
420 
421 		if (asprintf(&absname, "refs/%s%s%s",
422 		    subdir, subdir[0] ? "/" : "", name) == -1) {
423 			err = got_error_from_errno("asprintf");
424 			goto done;
425 		}
426 	}
427 
428 	err = parse_ref_file(ref, name, absname, path, lock);
429 done:
430 	if (!ref_is_absolute && !ref_is_well_known)
431 		free(absname);
432 	free(path);
433 	return err;
434 }
435 
436 const struct got_error *
437 got_ref_open(struct got_reference **ref, struct got_repository *repo,
438    const char *refname, int lock)
439 {
440 	const struct got_error *err = NULL;
441 	char *path_refs = NULL;
442 	const char *subdirs[] = {
443 	    GOT_REF_HEADS, GOT_REF_TAGS, GOT_REF_REMOTES
444 	};
445 	size_t i;
446 	int well_known = is_well_known_ref(refname);
447 	struct got_lockfile *lf = NULL;
448 
449 	*ref = NULL;
450 
451 	path_refs = get_refs_dir_path(repo, refname);
452 	if (path_refs == NULL) {
453 		err = got_error_from_errno2("get_refs_dir_path", refname);
454 		goto done;
455 	}
456 
457 	if (well_known) {
458 		err = open_ref(ref, path_refs, "", refname, lock);
459 	} else {
460 		char *packed_refs_path;
461 		FILE *f;
462 
463 		/* Search on-disk refs before packed refs! */
464 		for (i = 0; i < nitems(subdirs); i++) {
465 			err = open_ref(ref, path_refs, subdirs[i], refname,
466 			    lock);
467 			if ((err && err->code != GOT_ERR_NOT_REF) || *ref)
468 				goto done;
469 		}
470 
471 		packed_refs_path = got_repo_get_path_packed_refs(repo);
472 		if (packed_refs_path == NULL) {
473 			err = got_error_from_errno(
474 			    "got_repo_get_path_packed_refs");
475 			goto done;
476 		}
477 
478 		if (lock) {
479 			err = got_lockfile_lock(&lf, packed_refs_path);
480 			if (err)
481 				goto done;
482 		}
483 		f = fopen(packed_refs_path, "rb");
484 		free(packed_refs_path);
485 		if (f != NULL) {
486 			err = open_packed_ref(ref, f, subdirs, nitems(subdirs),
487 			    refname);
488 			if (!err) {
489 				if (fclose(f) == EOF) {
490 					err = got_error_from_errno("fclose");
491 					got_ref_close(*ref);
492 					*ref = NULL;
493 				} else if (*ref)
494 					(*ref)->lf = lf;
495 			}
496 		}
497 	}
498 done:
499 	if (!err && *ref == NULL)
500 		err = got_error_not_ref(refname);
501 	if (err && lf)
502 		got_lockfile_unlock(lf);
503 	free(path_refs);
504 	return err;
505 }
506 
507 void
508 got_ref_close(struct got_reference *ref)
509 {
510 	if (ref->flags & GOT_REF_IS_SYMBOLIC) {
511 		free(ref->ref.symref.name);
512 		free(ref->ref.symref.ref);
513 	} else
514 		free(ref->ref.ref.name);
515 	free(ref);
516 }
517 
518 struct got_reference *
519 got_ref_dup(struct got_reference *ref)
520 {
521 	struct got_reference *ret;
522 
523 	ret = calloc(1, sizeof(*ret));
524 	if (ret == NULL)
525 		return NULL;
526 
527 	ret->flags = ref->flags;
528 	if (ref->flags & GOT_REF_IS_SYMBOLIC) {
529 		ret->ref.symref.name = strdup(ref->ref.symref.name);
530 		if (ret->ref.symref.name == NULL) {
531 			free(ret);
532 			return NULL;
533 		}
534 		ret->ref.symref.ref = strdup(ref->ref.symref.ref);
535 		if (ret->ref.symref.ref == NULL) {
536 			free(ret->ref.symref.name);
537 			free(ret);
538 			return NULL;
539 		}
540 	} else {
541 		ret->ref.ref.name = strdup(ref->ref.ref.name);
542 		if (ret->ref.ref.name == NULL) {
543 			free(ret);
544 			return NULL;
545 		}
546 		memcpy(ret->ref.ref.sha1, ref->ref.ref.sha1,
547 		    sizeof(ret->ref.ref.sha1));
548 	}
549 
550 	return ret;
551 }
552 
553 const struct got_error *
554 got_reflist_entry_dup(struct got_reflist_entry **newp,
555     struct got_reflist_entry *re)
556 {
557 	const struct got_error *err = NULL;
558 	struct got_reflist_entry *new;
559 
560 	*newp = NULL;
561 
562 	new = malloc(sizeof(*new));
563 	if (new == NULL)
564 		return got_error_from_errno("malloc");
565 
566 	new->ref = got_ref_dup(re->ref);
567 	if (new->ref == NULL) {
568 		err = got_error_from_errno("got_ref_dup");
569 		free(new);
570 		return err;
571 	}
572 
573 	*newp = new;
574 	return NULL;
575 }
576 
577 static const struct got_error *
578 resolve_symbolic_ref(struct got_reference **resolved,
579     struct got_repository *repo, struct got_reference *ref)
580 {
581 	struct got_reference *nextref;
582 	const struct got_error *err;
583 
584 	err = got_ref_open(&nextref, repo, ref->ref.symref.ref, 0);
585 	if (err)
586 		return err;
587 
588 	if (nextref->flags & GOT_REF_IS_SYMBOLIC)
589 		err = resolve_symbolic_ref(resolved, repo, nextref);
590 	else
591 		*resolved = got_ref_dup(nextref);
592 
593 	got_ref_close(nextref);
594 	return err;
595 }
596 
597 static const struct got_error *
598 ref_resolve(struct got_object_id **id, struct got_repository *repo,
599     struct got_reference *ref, int recursion)
600 {
601 	const struct got_error *err;
602 
603 	if (recursion <= 0)
604 		return got_error_msg(GOT_ERR_RECURSION,
605 		    "reference recursion limit reached");
606 
607 	if (ref->flags & GOT_REF_IS_SYMBOLIC) {
608 		struct got_reference *resolved = NULL;
609 		err = resolve_symbolic_ref(&resolved, repo, ref);
610 		if (err == NULL)
611 			err = ref_resolve(id, repo, resolved, --recursion);
612 		if (resolved)
613 			got_ref_close(resolved);
614 		return err;
615 	}
616 
617 	*id = calloc(1, sizeof(**id));
618 	if (*id == NULL)
619 		return got_error_from_errno("calloc");
620 	memcpy((*id)->sha1, ref->ref.ref.sha1, sizeof((*id)->sha1));
621 	return NULL;
622 }
623 
624 const struct got_error *
625 got_ref_resolve(struct got_object_id **id, struct got_repository *repo,
626     struct got_reference *ref)
627 {
628 	return ref_resolve(id, repo, ref, GOT_REF_RECURSE_MAX);
629 }
630 
631 char *
632 got_ref_to_str(struct got_reference *ref)
633 {
634 	char *str;
635 
636 	if (ref->flags & GOT_REF_IS_SYMBOLIC)
637 		return strdup(ref->ref.symref.ref);
638 
639 	str = malloc(SHA1_DIGEST_STRING_LENGTH);
640 	if (str == NULL)
641 		return NULL;
642 
643 	if (got_sha1_digest_to_str(ref->ref.ref.sha1, str,
644 	    SHA1_DIGEST_STRING_LENGTH) == NULL) {
645 		free(str);
646 		return NULL;
647 	}
648 
649 	return str;
650 }
651 
652 const char *
653 got_ref_get_name(struct got_reference *ref)
654 {
655 	if (ref->flags & GOT_REF_IS_SYMBOLIC)
656 		return ref->ref.symref.name;
657 
658 	return ref->ref.ref.name;
659 }
660 
661 const char *
662 got_ref_get_symref_target(struct got_reference *ref)
663 {
664 	if (ref->flags & GOT_REF_IS_SYMBOLIC)
665 		return ref->ref.symref.ref;
666 
667 	return NULL;
668 }
669 
670 const struct got_error *
671 got_ref_cmp_by_name(void *arg, int *cmp, struct got_reference *re1,
672     struct got_reference* re2)
673 {
674 	const char *name1 = got_ref_get_name(re1);
675 	const char *name2 = got_ref_get_name(re2);
676 
677 	*cmp = got_path_cmp(name1, name2, strlen(name1), strlen(name2));
678 	return NULL;
679 }
680 
681 const struct got_error *
682 got_ref_cmp_tags(void *arg, int *cmp, struct got_reference *ref1,
683     struct got_reference *ref2)
684 {
685 	const struct got_error *err = NULL;
686 	struct got_repository *repo = arg;
687 	struct got_object_id *id1, *id2 = NULL;
688 	struct got_tag_object *tag1 = NULL, *tag2 = NULL;
689 	struct got_commit_object *commit1 = NULL, *commit2 = NULL;
690 	time_t time1, time2;
691 
692 	*cmp = 0;
693 
694 	err = got_ref_resolve(&id1, repo, ref1);
695 	if (err)
696 		return err;
697 	err = got_object_open_as_tag(&tag1, repo, id1);
698 	if (err) {
699 		if (err->code != GOT_ERR_OBJ_TYPE)
700 			goto done;
701 		/* "lightweight" tag */
702 		err = got_object_open_as_commit(&commit1, repo, id1);
703 		if (err)
704 			goto done;
705 		time1 = got_object_commit_get_committer_time(commit1);
706 	} else
707 		time1 = got_object_tag_get_tagger_time(tag1);
708 
709 	err = got_ref_resolve(&id2, repo, ref2);
710 	if (err)
711 		goto done;
712 	err = got_object_open_as_tag(&tag2, repo, id2);
713 	if (err) {
714 		if (err->code != GOT_ERR_OBJ_TYPE)
715 			goto done;
716 		/* "lightweight" tag */
717 		err = got_object_open_as_commit(&commit2, repo, id2);
718 		if (err)
719 			goto done;
720 		time2 = got_object_commit_get_committer_time(commit2);
721 	} else
722 		time2 = got_object_tag_get_tagger_time(tag2);
723 
724 	/* Put latest tags first. */
725 	if (time1 < time2)
726 		*cmp = 1;
727 	else if (time1 > time2)
728 		*cmp = -1;
729 	else
730 		err = got_ref_cmp_by_name(NULL, cmp, ref2, ref1);
731 done:
732 	free(id1);
733 	free(id2);
734 	if (tag1)
735 		got_object_tag_close(tag1);
736 	if (tag2)
737 		got_object_tag_close(tag2);
738 	if (commit1)
739 		got_object_commit_close(commit1);
740 	if (commit2)
741 		got_object_commit_close(commit2);
742 	return err;
743 }
744 
745 static const struct got_error *
746 insert_ref(struct got_reflist_entry **newp, struct got_reflist_head *refs,
747     struct got_reference *ref, struct got_repository *repo,
748     got_ref_cmp_cb cmp_cb, void *cmp_arg)
749 {
750 	const struct got_error *err;
751 	struct got_reflist_entry *new, *re;
752 	int cmp;
753 
754 	*newp = NULL;
755 
756 	new = malloc(sizeof(*new));
757 	if (new == NULL)
758 		return got_error_from_errno("malloc");
759 	new->ref = ref;
760 	*newp = new;
761 
762 	/*
763 	 * We must de-duplicate entries on insert because packed-refs may
764 	 * contain redundant entries. On-disk refs take precedence.
765 	 * This code assumes that on-disk revs are read before packed-refs.
766 	 * We're iterating the list anyway, so insert elements sorted by name.
767 	 *
768 	 * Many callers will provide paths in a somewhat sorted order.
769 	 * Iterating backwards from the tail of the list should be more
770 	 * efficient than traversing through the entire list each time
771 	 * an element is inserted.
772 	 */
773 	re = TAILQ_LAST(refs, got_reflist_head);
774 	while (re) {
775 		err = (*cmp_cb)(cmp_arg, &cmp, re->ref, new->ref);
776 		if (err)
777 			return err;
778 		if (cmp == 0) {
779 			/* duplicate */
780 			free(new);
781 			*newp = NULL;
782 			return NULL;
783 		} else if (cmp < 0) {
784 			TAILQ_INSERT_AFTER(refs, re, new, entry);
785 			return NULL;
786 		}
787 		re = TAILQ_PREV(re, got_reflist_head, entry);
788 	}
789 
790 	TAILQ_INSERT_HEAD(refs, new, entry);
791 	return NULL;
792 }
793 
794 static const struct got_error *
795 gather_on_disk_refs(struct got_reflist_head *refs, const char *path_refs,
796     const char *subdir, struct got_repository *repo,
797     got_ref_cmp_cb cmp_cb, void *cmp_arg)
798 {
799 	const struct got_error *err = NULL;
800 	DIR *d = NULL;
801 	char *path_subdir;
802 
803 	while (subdir[0] == '/')
804 		subdir++;
805 
806 	if (asprintf(&path_subdir, "%s/%s", path_refs, subdir) == -1)
807 		return got_error_from_errno("asprintf");
808 
809 	d = opendir(path_subdir);
810 	if (d == NULL)
811 		goto done;
812 
813 	for (;;) {
814 		struct dirent *dent;
815 		struct got_reference *ref;
816 		char *child;
817 		int type;
818 
819 		dent = readdir(d);
820 		if (dent == NULL)
821 			break;
822 
823 		if (strcmp(dent->d_name, ".") == 0 ||
824 		    strcmp(dent->d_name, "..") == 0)
825 			continue;
826 
827 		err = got_path_dirent_type(&type, path_subdir, dent);
828 		if (err)
829 			break;
830 
831 		switch (type) {
832 		case DT_REG:
833 			err = open_ref(&ref, path_refs, subdir, dent->d_name,
834 			    0);
835 			if (err)
836 				goto done;
837 			if (ref) {
838 				struct got_reflist_entry *new;
839 				err = insert_ref(&new, refs, ref, repo,
840 				    cmp_cb, cmp_arg);
841 				if (err || new == NULL /* duplicate */)
842 					got_ref_close(ref);
843 				if (err)
844 					goto done;
845 			}
846 			break;
847 		case DT_DIR:
848 			if (asprintf(&child, "%s%s%s", subdir,
849 			    subdir[0] == '\0' ? "" : "/", dent->d_name) == -1) {
850 				err = got_error_from_errno("asprintf");
851 				break;
852 			}
853 			err = gather_on_disk_refs(refs, path_refs, child, repo,
854 			    cmp_cb, cmp_arg);
855 			free(child);
856 			break;
857 		default:
858 			break;
859 		}
860 	}
861 done:
862 	if (d)
863 		closedir(d);
864 	free(path_subdir);
865 	return err;
866 }
867 
868 const struct got_error *
869 got_ref_list(struct got_reflist_head *refs, struct got_repository *repo,
870     const char *ref_namespace, got_ref_cmp_cb cmp_cb, void *cmp_arg)
871 {
872 	const struct got_error *err;
873 	char *packed_refs_path, *path_refs = NULL;
874 	char *abs_namespace = NULL;
875 	char *buf = NULL, *ondisk_ref_namespace = NULL;
876 	char *line = NULL;
877 	FILE *f = NULL;
878 	struct got_reference *ref;
879 	struct got_reflist_entry *new;
880 
881 	if (ref_namespace == NULL || ref_namespace[0] == '\0') {
882 		path_refs = get_refs_dir_path(repo, GOT_REF_HEAD);
883 		if (path_refs == NULL) {
884 			err = got_error_from_errno("get_refs_dir_path");
885 			goto done;
886 		}
887 		err = open_ref(&ref, path_refs, "", GOT_REF_HEAD, 0);
888 		if (err)
889 			goto done;
890 		err = insert_ref(&new, refs, ref, repo,
891 		    cmp_cb, cmp_arg);
892 		if (err || new == NULL /* duplicate */)
893 			got_ref_close(ref);
894 		if (err && err->code != GOT_ERR_NOT_REF)
895 			goto done;
896 	} else {
897 		/* Try listing a single reference. */
898 		const char *refname = ref_namespace;
899 		path_refs = get_refs_dir_path(repo, refname);
900 		if (path_refs == NULL) {
901 			err = got_error_from_errno("get_refs_dir_path");
902 			goto done;
903 		}
904 		err = open_ref(&ref, path_refs, "", refname, 0);
905 		if (err) {
906 			if (err->code != GOT_ERR_NOT_REF)
907 				goto done;
908 			/* Try to look up references in a given namespace. */
909 		} else {
910 			err = insert_ref(&new, refs, ref, repo,
911 			    cmp_cb, cmp_arg);
912 			if (err || new == NULL /* duplicate */)
913 				got_ref_close(ref);
914 			return err;
915 		}
916 	}
917 
918 	if (ref_namespace) {
919 		size_t len;
920 		/* Canonicalize the path to eliminate double-slashes if any. */
921 		if (asprintf(&abs_namespace, "/%s", ref_namespace) == -1) {
922 			err = got_error_from_errno("asprintf");
923 			goto done;
924 		}
925 		len = strlen(abs_namespace) + 1;
926 		buf = malloc(len);
927 		if (buf == NULL) {
928 			err = got_error_from_errno("malloc");
929 			goto done;
930 		}
931 		err = got_canonpath(abs_namespace, buf, len);
932 		if (err)
933 			goto done;
934 		ondisk_ref_namespace = buf;
935 		while (ondisk_ref_namespace[0] == '/')
936 			ondisk_ref_namespace++;
937 		if (strncmp(ondisk_ref_namespace, "refs/", 5) == 0)
938 			ondisk_ref_namespace += 5;
939 		else if (strcmp(ondisk_ref_namespace, "refs") == 0)
940 			ondisk_ref_namespace = "";
941 	}
942 
943 	/* Gather on-disk refs before parsing packed-refs. */
944 	free(path_refs);
945 	path_refs = get_refs_dir_path(repo, "");
946 	if (path_refs == NULL) {
947 		err = got_error_from_errno("get_refs_dir_path");
948 		goto done;
949 	}
950 	err = gather_on_disk_refs(refs, path_refs,
951 	    ondisk_ref_namespace ? ondisk_ref_namespace : "", repo,
952 	    cmp_cb, cmp_arg);
953 	if (err)
954 		goto done;
955 
956 	/*
957 	 * The packed-refs file may contain redundant entries, in which
958 	 * case on-disk refs take precedence.
959 	 */
960 	packed_refs_path = got_repo_get_path_packed_refs(repo);
961 	if (packed_refs_path == NULL) {
962 		err = got_error_from_errno("got_repo_get_path_packed_refs");
963 		goto done;
964 	}
965 
966 	f = fopen(packed_refs_path, "r");
967 	free(packed_refs_path);
968 	if (f) {
969 		size_t linesize = 0;
970 		ssize_t linelen;
971 		for (;;) {
972 			linelen = getline(&line, &linesize, f);
973 			if (linelen == -1) {
974 				if (feof(f))
975 					break;
976 				err = got_ferror(f, GOT_ERR_BAD_REF_DATA);
977 				goto done;
978 			}
979 			if (linelen > 0 && line[linelen - 1] == '\n')
980 				line[linelen - 1] = '\0';
981 			err = parse_packed_ref_line(&ref, NULL, line);
982 			if (err)
983 				goto done;
984 			if (ref) {
985 				if (ref_namespace) {
986 					const char *name;
987 					name = got_ref_get_name(ref);
988 					if (!got_path_is_child(name,
989 					    ref_namespace,
990 					    strlen(ref_namespace))) {
991 						got_ref_close(ref);
992 						continue;
993 					}
994 				}
995 				err = insert_ref(&new, refs, ref, repo,
996 				    cmp_cb, cmp_arg);
997 				if (err || new == NULL /* duplicate */)
998 					got_ref_close(ref);
999 				if (err)
1000 					goto done;
1001 			}
1002 		}
1003 	}
1004 done:
1005 	free(abs_namespace);
1006 	free(buf);
1007 	free(line);
1008 	free(path_refs);
1009 	if (f && fclose(f) == EOF && err == NULL)
1010 		err = got_error_from_errno("fclose");
1011 	return err;
1012 }
1013 
1014 void
1015 got_ref_list_free(struct got_reflist_head *refs)
1016 {
1017 	struct got_reflist_entry *re;
1018 
1019 	while ((re = TAILQ_FIRST(refs))) {
1020 		TAILQ_REMOVE(refs, re, entry);
1021 		free(re);
1022 	}
1023 
1024 }
1025 
1026 int
1027 got_ref_is_symbolic(struct got_reference *ref)
1028 {
1029 	return (ref->flags & GOT_REF_IS_SYMBOLIC);
1030 }
1031 
1032 const struct got_error *
1033 got_ref_change_ref(struct got_reference *ref, struct got_object_id *id)
1034 {
1035 	if (ref->flags & GOT_REF_IS_SYMBOLIC)
1036 		return got_error(GOT_ERR_BAD_REF_TYPE);
1037 
1038 	memcpy(ref->ref.ref.sha1, id->sha1, sizeof(ref->ref.ref.sha1));
1039 	return NULL;
1040 }
1041 
1042 const struct got_error *
1043 got_ref_change_symref(struct got_reference *ref, const char *refname)
1044 {
1045 	char *new_name;
1046 
1047 	if ((ref->flags & GOT_REF_IS_SYMBOLIC) == 0)
1048 		return got_error(GOT_ERR_BAD_REF_TYPE);
1049 
1050 	new_name = strdup(refname);
1051 	if (new_name == NULL)
1052 		return got_error_from_errno("strdup");
1053 
1054 	free(ref->ref.symref.ref);
1055 	ref->ref.symref.ref = new_name;
1056 	return NULL;
1057 }
1058 
1059 const struct got_error *
1060 got_ref_change_symref_to_ref(struct got_reference *symref,
1061     struct got_object_id *id)
1062 {
1063 	if ((symref->flags & GOT_REF_IS_SYMBOLIC) == 0)
1064 		return got_error(GOT_ERR_BAD_REF_TYPE);
1065 
1066 	symref->ref.ref.name = symref->ref.symref.name;
1067 	memcpy(symref->ref.ref.sha1, id->sha1, SHA1_DIGEST_LENGTH);
1068 	symref->flags &= ~GOT_REF_IS_SYMBOLIC;
1069 	return NULL;
1070 }
1071 
1072 const struct got_error *
1073 got_ref_write(struct got_reference *ref, struct got_repository *repo)
1074 {
1075 	const struct got_error *err = NULL, *unlock_err = NULL;
1076 	const char *name = got_ref_get_name(ref);
1077 	char *path_refs = NULL, *path = NULL, *tmppath = NULL;
1078 	struct got_lockfile *lf = NULL;
1079 	FILE *f = NULL;
1080 	size_t n;
1081 	struct stat sb;
1082 
1083 	path_refs = get_refs_dir_path(repo, name);
1084 	if (path_refs == NULL) {
1085 		err = got_error_from_errno2("get_refs_dir_path", name);
1086 		goto done;
1087 	}
1088 
1089 	if (asprintf(&path, "%s/%s", path_refs, name) == -1) {
1090 		err = got_error_from_errno("asprintf");
1091 		goto done;
1092 	}
1093 
1094 	err = got_opentemp_named(&tmppath, &f, path);
1095 	if (err) {
1096 		char *parent;
1097 		if (!(err->code == GOT_ERR_ERRNO && errno == ENOENT))
1098 			goto done;
1099 		err = got_path_dirname(&parent, path);
1100 		if (err)
1101 			goto done;
1102 		err = got_path_mkdir(parent);
1103 		free(parent);
1104 		if (err)
1105 			goto done;
1106 		err = got_opentemp_named(&tmppath, &f, path);
1107 		if (err)
1108 			goto done;
1109 	}
1110 
1111 	if (ref->flags & GOT_REF_IS_SYMBOLIC) {
1112 		n = fprintf(f, "ref: %s\n", ref->ref.symref.ref);
1113 		if (n != strlen(ref->ref.symref.ref) + 6) {
1114 			err = got_ferror(f, GOT_ERR_IO);
1115 			goto done;
1116 		}
1117 	} else {
1118 		char hex[SHA1_DIGEST_STRING_LENGTH];
1119 		if (got_sha1_digest_to_str(ref->ref.ref.sha1, hex,
1120 		    sizeof(hex)) == NULL) {
1121 			err = got_error(GOT_ERR_BAD_REF_DATA);
1122 			goto done;
1123 		}
1124 		n = fprintf(f, "%s\n", hex);
1125 		if (n != sizeof(hex)) {
1126 			err = got_ferror(f, GOT_ERR_IO);
1127 			goto done;
1128 		}
1129 	}
1130 
1131 	if (ref->lf == NULL) {
1132 		err = got_lockfile_lock(&lf, path);
1133 		if (err)
1134 			goto done;
1135 	}
1136 
1137 	/* XXX: check if old content matches our expectations? */
1138 
1139 	if (stat(path, &sb) != 0) {
1140 		if (errno != ENOENT) {
1141 			err = got_error_from_errno2("stat", path);
1142 			goto done;
1143 		}
1144 		sb.st_mode = GOT_DEFAULT_FILE_MODE;
1145 	}
1146 
1147 	if (fchmod(fileno(f), sb.st_mode) != 0) {
1148 		err = got_error_from_errno2("fchmod", tmppath);
1149 		goto done;
1150 	}
1151 
1152 	if (rename(tmppath, path) != 0) {
1153 		err = got_error_from_errno3("rename", tmppath, path);
1154 		goto done;
1155 	}
1156 	free(tmppath);
1157 	tmppath = NULL;
1158 done:
1159 	if (ref->lf == NULL && lf)
1160 		unlock_err = got_lockfile_unlock(lf);
1161 	if (f) {
1162 		if (fclose(f) == EOF && err == NULL)
1163 			err = got_error_from_errno("fclose");
1164 	}
1165 	free(path_refs);
1166 	free(path);
1167 	if (tmppath) {
1168 		if (unlink(tmppath) != 0 && err == NULL)
1169 			err = got_error_from_errno2("unlink", tmppath);
1170 		free(tmppath);
1171 	}
1172 	return err ? err : unlock_err;
1173 }
1174 
1175 static const struct got_error *
1176 delete_packed_ref(struct got_reference *delref, struct got_repository *repo)
1177 {
1178 	const struct got_error *err = NULL, *unlock_err = NULL;
1179 	struct got_lockfile *lf = NULL;
1180 	FILE *f = NULL, *tmpf = NULL;
1181 	char *line = NULL, *packed_refs_path, *tmppath = NULL;
1182 	size_t linesize = 0;
1183 	struct got_reflist_head refs;
1184 	int found_delref = 0;
1185 
1186 	/* The packed-refs file does not cotain symbolic references. */
1187 	if (delref->flags & GOT_REF_IS_SYMBOLIC)
1188 		return got_error(GOT_ERR_BAD_REF_DATA);
1189 
1190 	TAILQ_INIT(&refs);
1191 
1192 	packed_refs_path = got_repo_get_path_packed_refs(repo);
1193 	if (packed_refs_path == NULL)
1194 		return got_error_from_errno("got_repo_get_path_packed_refs");
1195 
1196 	err = got_opentemp_named(&tmppath, &tmpf, packed_refs_path);
1197 	if (err)
1198 		goto done;
1199 
1200 	if (delref->lf == NULL) {
1201 		err = got_lockfile_lock(&lf, packed_refs_path);
1202 		if (err)
1203 			goto done;
1204 	}
1205 
1206 	f = fopen(packed_refs_path, "r");
1207 	if (f == NULL) {
1208 		err = got_error_from_errno2("fopen", packed_refs_path);
1209 		goto done;
1210 	}
1211 	for (;;) {
1212 		ssize_t linelen;
1213 		struct got_reference *ref;
1214 		struct got_reflist_entry *new;
1215 
1216 		linelen = getline(&line, &linesize, f);
1217 		if (linelen == -1) {
1218 			if (feof(f))
1219 				break;
1220 			err = got_ferror(f, GOT_ERR_BAD_REF_DATA);
1221 			goto done;
1222 		}
1223 		if (linelen > 0 && line[linelen - 1] == '\n')
1224 			line[linelen - 1] = '\0';
1225 		err = parse_packed_ref_line(&ref, NULL, line);
1226 		if (err)
1227 			goto done;
1228 		if (ref == NULL)
1229 			continue;
1230 
1231 		if (strcmp(ref->ref.ref.name, delref->ref.ref.name) == 0 &&
1232 		    memcmp(ref->ref.ref.sha1, delref->ref.ref.sha1,
1233 		    sizeof(delref->ref.ref.sha1)) == 0) {
1234 			found_delref = 1;
1235 			got_ref_close(ref);
1236 			continue;
1237 		}
1238 
1239 		err = insert_ref(&new, &refs, ref, repo,
1240 		    got_ref_cmp_by_name, NULL);
1241 		if (err || new == NULL /* duplicate */)
1242 			got_ref_close(ref);
1243 		if (err)
1244 			goto done;
1245 	}
1246 
1247 	if (found_delref) {
1248 		struct got_reflist_entry *re;
1249 		size_t n;
1250 		struct stat sb;
1251 
1252 		n = fprintf(tmpf, "%s\n", GOT_PACKED_REFS_HEADER);
1253 		if (n != sizeof(GOT_PACKED_REFS_HEADER)) {
1254 			err = got_ferror(f, GOT_ERR_IO);
1255 			goto done;
1256 		}
1257 
1258 		TAILQ_FOREACH(re, &refs, entry) {
1259 			uint8_t hex[SHA1_DIGEST_STRING_LENGTH];
1260 
1261 			if (got_sha1_digest_to_str(re->ref->ref.ref.sha1, hex,
1262 			    sizeof(hex)) == NULL) {
1263 				err = got_error(GOT_ERR_BAD_REF_DATA);
1264 				goto done;
1265 			}
1266 			n = fprintf(tmpf, "%s ", hex);
1267 			if (n != sizeof(hex)) {
1268 				err = got_ferror(f, GOT_ERR_IO);
1269 				goto done;
1270 			}
1271 			n = fprintf(tmpf, "%s\n", re->ref->ref.ref.name);
1272 			if (n != strlen(re->ref->ref.ref.name) + 1) {
1273 				err = got_ferror(f, GOT_ERR_IO);
1274 				goto done;
1275 			}
1276 		}
1277 
1278 		if (fflush(tmpf) != 0) {
1279 			err = got_error_from_errno("fflush");
1280 			goto done;
1281 		}
1282 
1283 		if (fstat(fileno(f), &sb) != 0) {
1284 			if (errno != ENOENT) {
1285 				err = got_error_from_errno2("fstat",
1286 				    packed_refs_path);
1287 				goto done;
1288 			}
1289 			sb.st_mode = GOT_DEFAULT_FILE_MODE;
1290 		}
1291 
1292 		if (fchmod(fileno(tmpf), sb.st_mode) != 0) {
1293 			err = got_error_from_errno2("fchmod", tmppath);
1294 			goto done;
1295 		}
1296 
1297 		if (rename(tmppath, packed_refs_path) != 0) {
1298 			err = got_error_from_errno3("rename", tmppath,
1299 			    packed_refs_path);
1300 			goto done;
1301 		}
1302 	}
1303 done:
1304 	if (delref->lf == NULL && lf)
1305 		unlock_err = got_lockfile_unlock(lf);
1306 	if (f) {
1307 		if (fclose(f) == EOF && err == NULL)
1308 			err = got_error_from_errno("fclose");
1309 	}
1310 	if (tmpf) {
1311 		unlink(tmppath);
1312 		if (fclose(tmpf) == EOF && err == NULL)
1313 			err = got_error_from_errno("fclose");
1314 	}
1315 	free(tmppath);
1316 	free(packed_refs_path);
1317 	free(line);
1318 	got_ref_list_free(&refs);
1319 	return err ? err : unlock_err;
1320 }
1321 
1322 static const struct got_error *
1323 delete_loose_ref(struct got_reference *ref, struct got_repository *repo)
1324 {
1325 	const struct got_error *err = NULL, *unlock_err = NULL;
1326 	const char *name = got_ref_get_name(ref);
1327 	char *path_refs = NULL, *path = NULL;
1328 	struct got_lockfile *lf = NULL;
1329 
1330 	path_refs = get_refs_dir_path(repo, name);
1331 	if (path_refs == NULL) {
1332 		err = got_error_from_errno2("get_refs_dir_path", name);
1333 		goto done;
1334 	}
1335 
1336 	if (asprintf(&path, "%s/%s", path_refs, name) == -1) {
1337 		err = got_error_from_errno("asprintf");
1338 		goto done;
1339 	}
1340 
1341 	if (ref->lf == NULL) {
1342 		err = got_lockfile_lock(&lf, path);
1343 		if (err)
1344 			goto done;
1345 	}
1346 
1347 	/* XXX: check if old content matches our expectations? */
1348 
1349 	if (unlink(path) != 0)
1350 		err = got_error_from_errno2("unlink", path);
1351 done:
1352 	if (ref->lf == NULL && lf)
1353 		unlock_err = got_lockfile_unlock(lf);
1354 
1355 	free(path_refs);
1356 	free(path);
1357 	return err ? err : unlock_err;
1358 }
1359 
1360 const struct got_error *
1361 got_ref_delete(struct got_reference *ref, struct got_repository *repo)
1362 {
1363 	const struct got_error *err = NULL;
1364 	struct got_reference *ref2;
1365 
1366 	if (ref->flags & GOT_REF_IS_PACKED) {
1367 		err = delete_packed_ref(ref, repo);
1368 		if (err)
1369 			return err;
1370 
1371 		err = got_ref_open(&ref2, repo, got_ref_get_name(ref), 0);
1372 		if (err) {
1373 			if (err->code == GOT_ERR_NOT_REF)
1374 				return NULL;
1375 			return err;
1376 		}
1377 
1378 		err = delete_loose_ref(ref2, repo);
1379 		got_ref_close(ref2);
1380 		return err;
1381 	} else {
1382 		err = delete_loose_ref(ref, repo);
1383 		if (err)
1384 			return err;
1385 
1386 		err = got_ref_open(&ref2, repo, got_ref_get_name(ref), 0);
1387 		if (err) {
1388 			if (err->code == GOT_ERR_NOT_REF)
1389 				return NULL;
1390 			return err;
1391 		}
1392 
1393 		err = delete_packed_ref(ref2, repo);
1394 		got_ref_close(ref2);
1395 		return err;
1396 	}
1397 }
1398 
1399 const struct got_error *
1400 got_ref_unlock(struct got_reference *ref)
1401 {
1402 	const struct got_error *err;
1403 	err = got_lockfile_unlock(ref->lf);
1404 	ref->lf = NULL;
1405 	return err;
1406 }
1407 
1408 struct got_reflist_object_id_map {
1409 	struct got_object_idset *idset;
1410 };
1411 
1412 struct got_reflist_object_id_map_entry {
1413 	struct got_reflist_head refs;
1414 };
1415 
1416 static const struct got_error *
1417 add_object_id_map_entry(struct got_object_idset *idset,
1418     struct got_object_id *id, struct got_reflist_entry *re)
1419 {
1420 	const struct got_error *err = NULL;
1421 	struct got_reflist_object_id_map_entry *ent;
1422 	struct got_reflist_entry *new;
1423 
1424 	ent = got_object_idset_get(idset, id);
1425 	if (ent == NULL) {
1426 		ent = malloc(sizeof(*ent));
1427 		if (ent == NULL)
1428 			return got_error_from_errno("malloc");
1429 
1430 		TAILQ_INIT(&ent->refs);
1431 		err = got_object_idset_add(idset, id, ent);
1432 		if (err)
1433 			return err;
1434 	}
1435 
1436 	err = got_reflist_entry_dup(&new, re);
1437 	if (err)
1438 		return err;
1439 
1440 	TAILQ_INSERT_TAIL(&ent->refs, new, entry);
1441 	return NULL;
1442 }
1443 
1444 const struct got_error *
1445 got_reflist_object_id_map_create(struct got_reflist_object_id_map **map,
1446     struct got_reflist_head *refs, struct got_repository *repo)
1447 {
1448 	const struct got_error *err = NULL;
1449 	struct got_object_idset *idset;
1450 	struct got_object_id *id = NULL;
1451 	struct got_reflist_entry *re;
1452 
1453 	idset = got_object_idset_alloc();
1454 	if (idset == NULL)
1455 		return got_error_from_errno("got_object_idset_alloc");
1456 
1457 	*map = malloc(sizeof(**map));
1458 	if (*map == NULL) {
1459 		got_object_idset_free(idset);
1460 		return got_error_from_errno("malloc");
1461 	}
1462 	(*map)->idset = idset;
1463 
1464 	TAILQ_FOREACH(re, refs, entry) {
1465 		struct got_tag_object *tag = NULL;
1466 
1467 		err = got_ref_resolve(&id, repo, re->ref);
1468 		if (err)
1469 			goto done;
1470 
1471 		err = add_object_id_map_entry(idset, id, re);
1472 		if (err)
1473 			goto done;
1474 
1475 		if (strstr(got_ref_get_name(re->ref), "/tags/") == NULL) {
1476 			free(id);
1477 			id = NULL;
1478 			continue;
1479 		}
1480 
1481 		err = got_object_open_as_tag(&tag, repo, id);
1482 		if (err) {
1483 			if (err->code != GOT_ERR_OBJ_TYPE)
1484 				goto done;
1485 			/* Ref points at something other than a tag. */
1486 			err = NULL;
1487 			tag = NULL;
1488 			free(id);
1489 			id = NULL;
1490 			continue;
1491 		}
1492 
1493 		err = add_object_id_map_entry(idset,
1494 		    got_object_tag_get_object_id(tag), re);
1495 		got_object_tag_close(tag);
1496 		if (err)
1497 			goto done;
1498 
1499 		free(id);
1500 		id = NULL;
1501 	}
1502 done:
1503 	free(id);
1504 	if (err) {
1505 		got_reflist_object_id_map_free(*map);
1506 		*map = NULL;
1507 	}
1508 	return err;
1509 }
1510 
1511 struct got_reflist_head *
1512 got_reflist_object_id_map_lookup(struct got_reflist_object_id_map *map,
1513     struct got_object_id *id)
1514 {
1515 	struct got_reflist_object_id_map_entry *ent;
1516 	ent = got_object_idset_get(map->idset, id);
1517 	if (ent)
1518 		return &ent->refs;
1519 	return NULL;
1520 }
1521 
1522 static const struct got_error *
1523 free_id_map_entry(struct got_object_id *id, void *data, void *arg)
1524 {
1525 	struct got_reflist_object_id_map_entry *ent = data;
1526 
1527 	got_ref_list_free(&ent->refs);
1528 	free(ent);
1529 	return NULL;
1530 }
1531 
1532 void
1533 got_reflist_object_id_map_free(struct got_reflist_object_id_map *map)
1534 {
1535 	got_object_idset_for_each(map->idset, free_id_map_entry, NULL);
1536 	got_object_idset_free(map->idset);
1537 	free(map);
1538 }