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Date:: Mon Jul 22 08:35:46 2019 UTC
Message:: remove pointless call to got_path_normalize()
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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 <sha1.h>
25 #include <stdio.h>
26 #include <stdlib.h>
27 #include <string.h>
28 #include <util.h>
29 #include <zlib.h>
30 #include <time.h>
31 #include <libgen.h>
32 
33 #include "got_error.h"
34 #include "got_object.h"
35 #include "got_repository.h"
36 #include "got_reference.h"
37 #include "got_opentemp.h"
38 #include "got_path.h"
39 
40 #include "got_lib_sha1.h"
41 #include "got_lib_delta.h"
42 #include "got_lib_inflate.h"
43 #include "got_lib_object.h"
44 #include "got_lib_lockfile.h"
45 
46 #ifndef nitems
47 #define nitems(_a) (sizeof(_a) / sizeof((_a)[0]))
48 #endif
49 
50 #define GOT_REF_HEADS	"heads"
51 #define GOT_REF_TAGS	"tags"
52 #define GOT_REF_REMOTES	"remotes"
53 
54 /*
55  * We do not resolve tags yet, and don't yet care about sorting refs either,
56  * so packed-refs files we write contain a minimal header which disables all
57  * packed-refs "traits" supported by Git.
58  */
59 #define GOT_PACKED_REFS_HEADER	"# pack-refs with:"
60 
61 /* A symbolic reference. */
62 struct got_symref {
63 	char *name;
64 	char *ref;
65 };
66 
67 /* A non-symbolic reference (there is no better designation). */
68 struct got_ref {
69 	char *name;
70 	u_int8_t sha1[SHA1_DIGEST_LENGTH];
71 };
72 
73 /* A reference which points to an arbitrary object. */
74 struct got_reference {
75 	unsigned int flags;
76 #define GOT_REF_IS_SYMBOLIC	0x01
77 #define GOT_REF_IS_PACKED	0x02
78 
79 	union {
80 		struct got_ref ref;
81 		struct got_symref symref;
82 	} ref;
83 
84 	struct got_lockfile *lf;
85 };
86 
87 static const struct got_error *
88 alloc_ref(struct got_reference **ref, const char *name,
89     struct got_object_id *id, int flags)
90 {
91 	const struct got_error *err = NULL;
92 
93 	*ref = calloc(1, sizeof(**ref));
94 	if (*ref == NULL)
95 		return got_error_from_errno("calloc");
96 
97 	memcpy((*ref)->ref.ref.sha1, id->sha1, sizeof((*ref)->ref.ref.sha1));
98 	(*ref)->flags = flags;
99 	(*ref)->ref.ref.name = strdup(name);
100 	if ((*ref)->ref.ref.name == NULL) {
101 		err = got_error_from_errno("strdup");
102 		got_ref_close(*ref);
103 		*ref = NULL;
104 	}
105 	return err;
106 }
107 
108 static const struct got_error *
109 alloc_symref(struct got_reference **ref, const char *name,
110     const char *target_ref, int flags)
111 {
112 	const struct got_error *err = NULL;
113 
114 	*ref = calloc(1, sizeof(**ref));
115 	if (*ref == NULL)
116 		return got_error_from_errno("calloc");
117 
118 	(*ref)->flags = GOT_REF_IS_SYMBOLIC | flags;
119 	(*ref)->ref.symref.name = strdup(name);
120 	if ((*ref)->ref.symref.name == NULL) {
121 		err = got_error_from_errno("strdup");
122 		got_ref_close(*ref);
123 		*ref = NULL;
124 	}
125 	(*ref)->ref.symref.ref = strdup(target_ref);
126 	if ((*ref)->ref.symref.ref == NULL) {
127 		err = got_error_from_errno("strdup");
128 		got_ref_close(*ref);
129 		*ref = NULL;
130 	}
131 	return err;
132 }
133 
134 static const struct got_error *
135 parse_symref(struct got_reference **ref, const char *name, const char *line)
136 {
137 	if (line[0] == '\0')
138 		return got_error(GOT_ERR_BAD_REF_DATA);
139 
140 	return alloc_symref(ref, name, line, 0);
141 }
142 
143 static const struct got_error *
144 parse_ref_line(struct got_reference **ref, const char *name, const char *line)
145 {
146 	struct got_object_id id;
147 
148 	if (strncmp(line, "ref: ", 5) == 0) {
149 		line += 5;
150 		return parse_symref(ref, name, line);
151 	}
152 
153 	if (!got_parse_sha1_digest(id.sha1, line))
154 		return got_error(GOT_ERR_BAD_REF_DATA);
155 
156 	return alloc_ref(ref, name, &id, 0);
157 }
158 
159 static const struct got_error *
160 parse_ref_file(struct got_reference **ref, const char *name,
161     const char *abspath, int lock)
162 {
163 	const struct got_error *err = NULL;
164 	FILE *f;
165 	char *line;
166 	size_t len;
167 	const char delim[3] = {'\0', '\0', '\0'};
168 	struct got_lockfile *lf = NULL;
169 
170 	if (lock) {
171 		err = got_lockfile_lock(&lf, abspath);
172 		if (err)
173 			return (err);
174 	}
175 
176 	f = fopen(abspath, "rb");
177 	if (f == NULL) {
178 		if (lock)
179 			got_lockfile_unlock(lf);
180 		return NULL;
181 	}
182 
183 	line = fparseln(f, &len, NULL, delim, 0);
184 	if (line == NULL) {
185 		err = got_error(GOT_ERR_BAD_REF_DATA);
186 		if (lock)
187 			got_lockfile_unlock(lf);
188 		goto done;
189 	}
190 
191 	err = parse_ref_line(ref, name, line);
192 	if (lock) {
193 		if (err)
194 			got_lockfile_unlock(lf);
195 		else {
196 			if (*ref)
197 				(*ref)->lf = lf;
198 			else
199 				got_lockfile_unlock(lf);
200 		}
201 	}
202 done:
203 	free(line);
204 	if (fclose(f) != 0 && err == NULL) {
205 		err = got_error_from_errno("fclose");
206 		if (*ref) {
207 			if (lock)
208 				got_ref_unlock(*ref);
209 			got_ref_close(*ref);
210 			*ref = NULL;
211 		}
212 	}
213 	return err;
214 }
215 
216 static int
217 is_well_known_ref(const char *refname)
218 {
219 	return (strcmp(refname, GOT_REF_HEAD) == 0 ||
220 	    strcmp(refname, GOT_REF_ORIG_HEAD) == 0 ||
221 	    strcmp(refname, GOT_REF_MERGE_HEAD) == 0 ||
222 	    strcmp(refname, GOT_REF_FETCH_HEAD) == 0);
223 }
224 
225 static char *
226 get_refs_dir_path(struct got_repository *repo, const char *refname)
227 {
228 	if (is_well_known_ref(refname) || strncmp(refname, "refs/", 5) == 0)
229 		return strdup(got_repo_get_path_git_dir(repo));
230 
231 	return got_repo_get_path_refs(repo);
232 }
233 
234 static int
235 is_valid_ref_name(const char *name)
236 {
237 	const char *s, *slash, *seg;
238 	const char forbidden[] = { ' ', '~', '^', ':', '?', '*', '[' , '\\' };
239 	const char *forbidden_seq[] = { "//", "..", "@{" };
240 	const char *lfs = GOT_LOCKFILE_SUFFIX;
241 	const size_t lfs_len = sizeof(GOT_LOCKFILE_SUFFIX) - 1;
242 	int i;
243 
244 	if (name[0] == '@' && name[1] == '\0')
245 		return 0;
246 
247 	slash = strchr(name, '/');
248 	if (slash == NULL)
249 		return 0;
250 
251 	s = name;
252 	seg = s;
253 	if (seg[0] == '\0' || seg[0] == '.' || seg[0] == '/')
254 		return 0;
255 	while (*s) {
256 		for (i = 0; i < nitems(forbidden); i++) {
257 			if (*s == forbidden[i])
258 				return 0;
259 		}
260 		for (i = 0; i < nitems(forbidden_seq); i++) {
261 			if (s[0] == forbidden_seq[i][0] &&
262 			    s[1] == forbidden_seq[i][1])
263 				return 0;
264 		}
265 		if (iscntrl((unsigned char)s[0]))
266 			return 0;
267 		if (s[0] == '.' && s[1] == '\0')
268 			return 0;
269 		if (*s == '/') {
270 			const char *nextseg = s + 1;
271 			if (nextseg[0] == '\0' || nextseg[0] == '.' ||
272 			    nextseg[0] == '/')
273 				return 0;
274 			if (seg <= s - lfs_len &&
275 			    strncmp(s - lfs_len, lfs, lfs_len) == 0)
276 				return 0;
277 			seg = nextseg;
278 		}
279 		s++;
280 	}
281 
282 	if (seg <= s - lfs_len &&
283 	    strncmp(s - lfs_len, lfs, lfs_len) == 0)
284 		return 0;
285 
286 	return 1;
287 }
288 
289 const struct got_error *
290 got_ref_alloc(struct got_reference **ref, const char *name,
291     struct got_object_id *id)
292 {
293 	if (!is_valid_ref_name(name))
294 		return got_error(GOT_ERR_BAD_REF_NAME);
295 
296 	return alloc_ref(ref, name, id, 0);
297 }
298 
299 const struct got_error *
300 got_ref_alloc_symref(struct got_reference **ref, const char *name,
301 	struct got_reference *target_ref)
302 {
303 	if (!is_valid_ref_name(name))
304 		return got_error(GOT_ERR_BAD_REF_NAME);
305 
306 	return alloc_symref(ref, name, got_ref_get_name(target_ref), 0);
307 }
308 
309 static const struct got_error *
310 parse_packed_ref_line(struct got_reference **ref, const char *abs_refname,
311     const char *line)
312 {
313 	struct got_object_id id;
314 	const char *name;
315 
316 	*ref = NULL;
317 
318 	if (line[0] == '#' || line[0] == '^')
319 		return NULL;
320 
321 	if (!got_parse_sha1_digest(id.sha1, line))
322 		return got_error(GOT_ERR_BAD_REF_DATA);
323 
324 	if (abs_refname) {
325 		if (strcmp(line + SHA1_DIGEST_STRING_LENGTH, abs_refname) != 0)
326 			return NULL;
327 		name = abs_refname;
328 	} else
329 		name = line + SHA1_DIGEST_STRING_LENGTH;
330 
331 	return alloc_ref(ref, name, &id, GOT_REF_IS_PACKED);
332 }
333 
334 static const struct got_error *
335 open_packed_ref(struct got_reference **ref, FILE *f, const char **subdirs,
336     int nsubdirs, const char *refname)
337 {
338 	const struct got_error *err = NULL;
339 	char *abs_refname;
340 	char *line;
341 	size_t len;
342 	const char delim[3] = {'\0', '\0', '\0'};
343 	int i, ref_is_absolute = (strncmp(refname, "refs/", 5) == 0);
344 
345 	*ref = NULL;
346 
347 	if (ref_is_absolute)
348 		abs_refname = (char *)refname;
349 	do {
350 		line = fparseln(f, &len, NULL, delim, 0);
351 		if (line == NULL) {
352 			if (feof(f))
353 				break;
354 			err = got_ferror(f, GOT_ERR_BAD_REF_DATA);
355 			break;
356 		}
357 		for (i = 0; i < nsubdirs; i++) {
358 			if (!ref_is_absolute &&
359 			    asprintf(&abs_refname, "refs/%s/%s", subdirs[i],
360 			    refname) == -1)
361 				return got_error_from_errno("asprintf");
362 			err = parse_packed_ref_line(ref, abs_refname, line);
363 			if (!ref_is_absolute)
364 				free(abs_refname);
365 			if (err || *ref != NULL)
366 				break;
367 		}
368 		free(line);
369 		if (err)
370 			break;
371 	} while (*ref == NULL);
372 
373 	return err;
374 }
375 
376 static const struct got_error *
377 open_ref(struct got_reference **ref, const char *path_refs, const char *subdir,
378     const char *name, int lock)
379 {
380 	const struct got_error *err = NULL;
381 	char *path = NULL;
382 	char *absname = NULL;
383 	int ref_is_absolute = (strncmp(name, "refs/", 5) == 0);
384 	int ref_is_well_known = is_well_known_ref(name);
385 
386 	*ref = NULL;
387 
388 	if (ref_is_absolute || ref_is_well_known) {
389 		if (asprintf(&path, "%s/%s", path_refs, name) == -1)
390 			return got_error_from_errno("asprintf");
391 		absname = (char *)name;
392 	} else {
393 		if (asprintf(&path, "%s/%s%s%s", path_refs, subdir,
394 		    subdir[0] ? "/" : "", name) == -1)
395 			return got_error_from_errno("asprintf");
396 
397 		if (asprintf(&absname, "refs/%s%s%s",
398 		    subdir, subdir[0] ? "/" : "", name) == -1) {
399 			err = got_error_from_errno("asprintf");
400 			goto done;
401 		}
402 	}
403 
404 	err = parse_ref_file(ref, absname, path, lock);
405 done:
406 	if (!ref_is_absolute && !ref_is_well_known)
407 		free(absname);
408 	free(path);
409 	return err;
410 }
411 
412 const struct got_error *
413 got_ref_open(struct got_reference **ref, struct got_repository *repo,
414    const char *refname, int lock)
415 {
416 	const struct got_error *err = NULL;
417 	char *path_refs = NULL;
418 	const char *subdirs[] = {
419 	    GOT_REF_HEADS, GOT_REF_TAGS, GOT_REF_REMOTES
420 	};
421 	int i, well_known = is_well_known_ref(refname);
422 	struct got_lockfile *lf = NULL;
423 
424 	*ref = NULL;
425 
426 	path_refs = get_refs_dir_path(repo, refname);
427 	if (path_refs == NULL) {
428 		err = got_error_from_errno2("get_refs_dir_path", refname);
429 		goto done;
430 	}
431 
432 	if (well_known) {
433 		err = open_ref(ref, path_refs, "", refname, lock);
434 	} else {
435 		char *packed_refs_path;
436 		FILE *f;
437 
438 		/* Search on-disk refs before packed refs! */
439 		for (i = 0; i < nitems(subdirs); i++) {
440 			err = open_ref(ref, path_refs, subdirs[i], refname,
441 			    lock);
442 			if (err || *ref)
443 				goto done;
444 		}
445 
446 		packed_refs_path = got_repo_get_path_packed_refs(repo);
447 		if (packed_refs_path == NULL) {
448 			err = got_error_from_errno(
449 			    "got_repo_get_path_packed_refs");
450 			goto done;
451 		}
452 
453 		if (lock) {
454 			err = got_lockfile_lock(&lf, packed_refs_path);
455 			if (err)
456 				goto done;
457 		}
458 		f = fopen(packed_refs_path, "rb");
459 		free(packed_refs_path);
460 		if (f != NULL) {
461 			err = open_packed_ref(ref, f, subdirs, nitems(subdirs),
462 			    refname);
463 			if (!err) {
464 				if (fclose(f) != 0) {
465 					err = got_error_from_errno("fclose");
466 					got_ref_close(*ref);
467 					*ref = NULL;
468 				} else if (*ref)
469 					(*ref)->lf = lf;
470 			}
471 		}
472 	}
473 done:
474 	if (!err && *ref == NULL)
475 		err = got_error_not_ref(refname);
476 	if (err && lf)
477 		got_lockfile_unlock(lf);
478 	free(path_refs);
479 	return err;
480 }
481 
482 void
483 got_ref_close(struct got_reference *ref)
484 {
485 	if (ref->flags & GOT_REF_IS_SYMBOLIC) {
486 		free(ref->ref.symref.name);
487 		free(ref->ref.symref.ref);
488 	} else
489 		free(ref->ref.ref.name);
490 	free(ref);
491 }
492 
493 struct got_reference *
494 got_ref_dup(struct got_reference *ref)
495 {
496 	struct got_reference *ret;
497 
498 	ret = calloc(1, sizeof(*ret));
499 	if (ret == NULL)
500 		return NULL;
501 
502 	ret->flags = ref->flags;
503 	if (ref->flags & GOT_REF_IS_SYMBOLIC) {
504 		ret->ref.symref.name = strdup(ref->ref.symref.name);
505 		if (ret->ref.symref.name == NULL) {
506 			free(ret);
507 			return NULL;
508 		}
509 		ret->ref.symref.ref = strdup(ref->ref.symref.ref);
510 		if (ret->ref.symref.ref == NULL) {
511 			free(ret->ref.symref.name);
512 			free(ret);
513 			return NULL;
514 		}
515 	} else {
516 		ref->ref.ref.name = strdup(ref->ref.ref.name);
517 		if (ref->ref.ref.name == NULL) {
518 			free(ret);
519 			return NULL;
520 		}
521 		memcpy(ret->ref.ref.sha1, ref->ref.ref.sha1,
522 		    sizeof(ret->ref.ref.sha1));
523 	}
524 
525 	return ret;
526 }
527 
528 static const struct got_error *
529 resolve_symbolic_ref(struct got_reference **resolved,
530     struct got_repository *repo, struct got_reference *ref)
531 {
532 	struct got_reference *nextref;
533 	const struct got_error *err;
534 
535 	err = got_ref_open(&nextref, repo, ref->ref.symref.ref, 0);
536 	if (err)
537 		return err;
538 
539 	if (nextref->flags & GOT_REF_IS_SYMBOLIC)
540 		err = resolve_symbolic_ref(resolved, repo, nextref);
541 	else
542 		*resolved = got_ref_dup(nextref);
543 
544 	got_ref_close(nextref);
545 	return err;
546 }
547 
548 const struct got_error *
549 got_ref_resolve(struct got_object_id **id, struct got_repository *repo,
550     struct got_reference *ref)
551 {
552 	const struct got_error *err;
553 
554 	if (ref->flags & GOT_REF_IS_SYMBOLIC) {
555 		struct got_reference *resolved = NULL;
556 		err = resolve_symbolic_ref(&resolved, repo, ref);
557 		if (err == NULL)
558 			err = got_ref_resolve(id, repo, resolved);
559 		if (resolved)
560 			got_ref_close(resolved);
561 		return err;
562 	}
563 
564 	*id = calloc(1, sizeof(**id));
565 	if (*id == NULL)
566 		return got_error_from_errno("calloc");
567 	memcpy((*id)->sha1, ref->ref.ref.sha1, sizeof((*id)->sha1));
568 	return NULL;
569 }
570 
571 char *
572 got_ref_to_str(struct got_reference *ref)
573 {
574 	char *str;
575 
576 	if (ref->flags & GOT_REF_IS_SYMBOLIC)
577 		return strdup(ref->ref.symref.ref);
578 
579 	str = malloc(SHA1_DIGEST_STRING_LENGTH);
580 	if (str == NULL)
581 		return NULL;
582 
583 	if (got_sha1_digest_to_str(ref->ref.ref.sha1, str,
584 	    SHA1_DIGEST_STRING_LENGTH) == NULL) {
585 		free(str);
586 		return NULL;
587 	}
588 
589 	return str;
590 }
591 
592 const char *
593 got_ref_get_name(struct got_reference *ref)
594 {
595 	if (ref->flags & GOT_REF_IS_SYMBOLIC)
596 		return ref->ref.symref.name;
597 
598 	return ref->ref.ref.name;
599 }
600 
601 const char *
602 got_ref_get_symref_target(struct got_reference *ref)
603 {
604 	if (ref->flags & GOT_REF_IS_SYMBOLIC)
605 		return ref->ref.symref.ref;
606 
607 	return NULL;
608 }
609 
610 static const struct got_error *
611 insert_ref(struct got_reflist_entry **newp, struct got_reflist_head *refs,
612     struct got_reference *ref, struct got_repository *repo)
613 {
614 	const struct got_error *err;
615 	struct got_object_id *id;
616 	struct got_reflist_entry *new, *re, *prev = NULL;
617 	int cmp;
618 
619 	*newp = NULL;
620 
621 	err = got_ref_resolve(&id, repo, ref);
622 	if (err)
623 		return err;
624 
625 	new = malloc(sizeof(*new));
626 	if (new == NULL) {
627 		free(id);
628 		return got_error_from_errno("malloc");
629 	}
630 	new->ref = ref;
631 	new->id = id;
632 	*newp = new;
633 
634 	/*
635 	 * We must de-duplicate entries on insert because packed-refs may
636 	 * contain redundant entries. On-disk refs take precedence.
637 	 * This code assumes that on-disk revs are read before packed-refs.
638 	 * We're iterating the list anyway, so insert elements sorted by name.
639 	 */
640 	re = SIMPLEQ_FIRST(refs);
641 	while (re) {
642 		cmp = got_path_cmp(got_ref_get_name(re->ref),
643 		    got_ref_get_name(new->ref));
644 		if (cmp == 0) {
645 			/* duplicate */
646 			free(new->id);
647 			free(new);
648 			*newp = NULL;
649 			return NULL;
650 		} else if (cmp > 0) {
651 			if (prev)
652 				SIMPLEQ_INSERT_AFTER(refs, prev, new, entry);
653 			else
654 				SIMPLEQ_INSERT_HEAD(refs, new, entry);
655 			return NULL;
656 		} else {
657 			prev = re;
658 			re = SIMPLEQ_NEXT(re, entry);
659 		}
660 	}
661 
662 	SIMPLEQ_INSERT_TAIL(refs, new, entry);
663 	return NULL;
664 }
665 
666 static const struct got_error *
667 gather_on_disk_refs(struct got_reflist_head *refs, const char *path_refs,
668     const char *subdir, struct got_repository *repo)
669 {
670 	const struct got_error *err = NULL;
671 	DIR *d = NULL;
672 	char *path_subdir;
673 
674 	if (asprintf(&path_subdir, "%s/%s", path_refs, subdir) == -1)
675 		return got_error_from_errno("asprintf");
676 
677 	d = opendir(path_subdir);
678 	if (d == NULL)
679 		goto done;
680 
681 	for (;;) {
682 		struct dirent *dent;
683 		struct got_reference *ref;
684 		char *child;
685 
686 		dent = readdir(d);
687 		if (dent == NULL)
688 			break;
689 
690 		if (strcmp(dent->d_name, ".") == 0 ||
691 		    strcmp(dent->d_name, "..") == 0)
692 			continue;
693 
694 		switch (dent->d_type) {
695 		case DT_REG:
696 			err = open_ref(&ref, path_refs, subdir, dent->d_name,
697 			    0);
698 			if (err)
699 				goto done;
700 			if (ref) {
701 				struct got_reflist_entry *new;
702 				err = insert_ref(&new, refs, ref, repo);
703 				if (err || new == NULL /* duplicate */)
704 					got_ref_close(ref);
705 				if (err)
706 					goto done;
707 			}
708 			break;
709 		case DT_DIR:
710 			if (asprintf(&child, "%s%s%s", subdir,
711 			    subdir[0] == '\0' ? "" : "/", dent->d_name) == -1) {
712 				err = got_error_from_errno("asprintf");
713 				break;
714 			}
715 			err = gather_on_disk_refs(refs, path_refs, child, repo);
716 			free(child);
717 			break;
718 		default:
719 			break;
720 		}
721 	}
722 done:
723 	if (d)
724 		closedir(d);
725 	free(path_subdir);
726 	return err;
727 }
728 
729 const struct got_error *
730 got_ref_list(struct got_reflist_head *refs, struct got_repository *repo)
731 {
732 	const struct got_error *err;
733 	char *packed_refs_path, *path_refs = NULL;
734 	FILE *f = NULL;
735 	struct got_reference *ref;
736 	struct got_reflist_entry *new;
737 
738 	/* HEAD ref should always exist. */
739 	path_refs = get_refs_dir_path(repo, GOT_REF_HEAD);
740 	if (path_refs == NULL) {
741 		err = got_error_from_errno("get_refs_dir_path");
742 		goto done;
743 	}
744 	err = open_ref(&ref, path_refs, "", GOT_REF_HEAD, 0);
745 	if (err)
746 		goto done;
747 	err = insert_ref(&new, refs, ref, repo);
748 	if (err || new == NULL /* duplicate */)
749 		got_ref_close(ref);
750 	if (err)
751 		goto done;
752 
753 	/* Gather on-disk refs before parsing packed-refs. */
754 	free(path_refs);
755 	path_refs = get_refs_dir_path(repo, "");
756 	if (path_refs == NULL) {
757 		err = got_error_from_errno("get_refs_dir_path");
758 		goto done;
759 	}
760 	err = gather_on_disk_refs(refs, path_refs, "", repo);
761 	if (err)
762 		goto done;
763 
764 	/*
765 	 * The packed-refs file may contain redundant entries, in which
766 	 * case on-disk refs take precedence.
767 	 */
768 	packed_refs_path = got_repo_get_path_packed_refs(repo);
769 	if (packed_refs_path == NULL) {
770 		err = got_error_from_errno("got_repo_get_path_packed_refs");
771 		goto done;
772 	}
773 
774 	f = fopen(packed_refs_path, "r");
775 	free(packed_refs_path);
776 	if (f) {
777 		char *line;
778 		size_t len;
779 		const char delim[3] = {'\0', '\0', '\0'};
780 		for (;;) {
781 			line = fparseln(f, &len, NULL, delim, 0);
782 			if (line == NULL) {
783 				if (feof(f))
784 					break;
785 				err = got_ferror(f, GOT_ERR_BAD_REF_DATA);
786 				goto done;
787 			}
788 			err = parse_packed_ref_line(&ref, NULL, line);
789 			free(line);
790 			if (err)
791 				goto done;
792 			if (ref) {
793 				err = insert_ref(&new, refs, ref, repo);
794 				if (err || new == NULL /* duplicate */)
795 					got_ref_close(ref);
796 				if (err)
797 					goto done;
798 			}
799 		}
800 	}
801 done:
802 	free(path_refs);
803 	if (f && fclose(f) != 0 && err == NULL)
804 		err = got_error_from_errno("fclose");
805 	return err;
806 }
807 
808 void
809 got_ref_list_free(struct got_reflist_head *refs)
810 {
811 	struct got_reflist_entry *re;
812 
813 	while (!SIMPLEQ_EMPTY(refs)) {
814 		re = SIMPLEQ_FIRST(refs);
815 		SIMPLEQ_REMOVE_HEAD(refs, entry);
816 		got_ref_close(re->ref);
817 		free(re->id);
818 		free(re);
819 	}
820 
821 }
822 
823 int
824 got_ref_is_symbolic(struct got_reference *ref)
825 {
826 	return (ref->flags & GOT_REF_IS_SYMBOLIC);
827 }
828 
829 const struct got_error *
830 got_ref_change_ref(struct got_reference *ref, struct got_object_id *id)
831 {
832 	if (ref->flags & GOT_REF_IS_SYMBOLIC)
833 		return got_error(GOT_ERR_BAD_REF_TYPE);
834 
835 	memcpy(ref->ref.ref.sha1, id->sha1, sizeof(ref->ref.ref.sha1));
836 	return NULL;
837 }
838 
839 const struct got_error *
840 got_ref_change_symref(struct got_reference *ref, char *refname)
841 {
842 	char *new_name;
843 
844 	if ((ref->flags & GOT_REF_IS_SYMBOLIC) == 0)
845 		return got_error(GOT_ERR_BAD_REF_TYPE);
846 
847 	new_name = strdup(refname);
848 	if (new_name == NULL)
849 		return got_error_from_errno("strdup");
850 
851 	free(ref->ref.symref.name);
852 	ref->ref.symref.name = new_name;
853 	return NULL;
854 }
855 
856 const struct got_error *
857 got_ref_write(struct got_reference *ref, struct got_repository *repo)
858 {
859 	const struct got_error *err = NULL, *unlock_err = NULL;
860 	const char *name = got_ref_get_name(ref);
861 	char *path_refs = NULL, *path = NULL, *tmppath = NULL;
862 	struct got_lockfile *lf = NULL;
863 	FILE *f = NULL;
864 	size_t n;
865 	struct stat sb;
866 
867 	path_refs = get_refs_dir_path(repo, name);
868 	if (path_refs == NULL) {
869 		err = got_error_from_errno2("get_refs_dir_path", name);
870 		goto done;
871 	}
872 
873 	if (asprintf(&path, "%s/%s", path_refs, name) == -1) {
874 		err = got_error_from_errno("asprintf");
875 		goto done;
876 	}
877 
878 	err = got_opentemp_named(&tmppath, &f, path);
879 	if (err) {
880 		char *parent;
881 		if (!(err->code == GOT_ERR_ERRNO && errno == ENOENT))
882 			goto done;
883 		err = got_path_dirname(&parent, path);
884 		if (err)
885 			goto done;
886 		err = got_path_mkdir(parent);
887 		free(parent);
888 		if (err)
889 			goto done;
890 		err = got_opentemp_named(&tmppath, &f, path);
891 		if (err)
892 			goto done;
893 	}
894 
895 	if (ref->flags & GOT_REF_IS_SYMBOLIC) {
896 		n = fprintf(f, "ref: %s\n", ref->ref.symref.ref);
897 		if (n != strlen(ref->ref.symref.ref) + 6) {
898 			err = got_ferror(f, GOT_ERR_IO);
899 			goto done;
900 		}
901 	} else {
902 		char hex[SHA1_DIGEST_STRING_LENGTH];
903 		if (got_sha1_digest_to_str(ref->ref.ref.sha1, hex,
904 		    sizeof(hex)) == NULL) {
905 			err = got_error(GOT_ERR_BAD_REF_DATA);
906 			goto done;
907 		}
908 		n = fprintf(f, "%s\n", hex);
909 		if (n != sizeof(hex)) {
910 			err = got_ferror(f, GOT_ERR_IO);
911 			goto done;
912 		}
913 	}
914 
915 	if (ref->lf == NULL) {
916 		err = got_lockfile_lock(&lf, path);
917 		if (err)
918 			goto done;
919 	}
920 
921 	/* XXX: check if old content matches our expectations? */
922 
923 	if (stat(path, &sb) != 0) {
924 		if (errno != ENOENT) {
925 			err = got_error_from_errno2("stat", path);
926 			goto done;
927 		}
928 		sb.st_mode = GOT_DEFAULT_FILE_MODE;
929 	}
930 
931 	if (rename(tmppath, path) != 0) {
932 		err = got_error_from_errno3("rename", tmppath, path);
933 		goto done;
934 	}
935 	free(tmppath);
936 	tmppath = NULL;
937 
938 	if (chmod(path, sb.st_mode) != 0) {
939 		err = got_error_from_errno2("chmod", path);
940 		goto done;
941 	}
942 done:
943 	if (ref->lf == NULL && lf)
944 		unlock_err = got_lockfile_unlock(lf);
945 	if (f) {
946 		if (fclose(f) != 0 && err == NULL)
947 			err = got_error_from_errno("fclose");
948 	}
949 	free(path_refs);
950 	free(path);
951 	if (tmppath) {
952 		if (unlink(tmppath) != 0 && err == NULL)
953 			err = got_error_from_errno2("unlink", tmppath);
954 		free(tmppath);
955 	}
956 	return err ? err : unlock_err;
957 }
958 
959 static const struct got_error *
960 delete_packed_ref(struct got_reference *delref, struct got_repository *repo)
961 {
962 	const struct got_error *err = NULL, *unlock_err = NULL;
963 	struct got_lockfile *lf = NULL;
964 	FILE *f = NULL, *tmpf = NULL;
965 	char *packed_refs_path, *tmppath = NULL;
966 	struct got_reflist_head refs;
967 	int found_delref = 0;
968 
969 	/* The packed-refs file does not cotain symbolic references. */
970 	if (delref->flags & GOT_REF_IS_SYMBOLIC)
971 		return got_error(GOT_ERR_BAD_REF_DATA);
972 
973 	SIMPLEQ_INIT(&refs);
974 
975 	packed_refs_path = got_repo_get_path_packed_refs(repo);
976 	if (packed_refs_path == NULL)
977 		return got_error_from_errno("got_repo_get_path_packed_refs");
978 
979 	err = got_opentemp_named(&tmppath, &tmpf, packed_refs_path);
980 	if (err)
981 		goto done;
982 
983 	if (delref->lf == NULL) {
984 		err = got_lockfile_lock(&lf, packed_refs_path);
985 		if (err)
986 			goto done;
987 	}
988 
989 	f = fopen(packed_refs_path, "r");
990 	if (f == NULL) {
991 		err = got_error_from_errno2("fopen", packed_refs_path);
992 		goto done;
993 	}
994 	for (;;) {
995 		char *line;
996 		size_t len;
997 		const char delim[3] = {'\0', '\0', '\0'};
998 		struct got_reference *ref;
999 		struct got_reflist_entry *new;
1000 
1001 		line = fparseln(f, &len, NULL, delim, 0);
1002 		if (line == NULL) {
1003 			if (feof(f))
1004 				break;
1005 			err = got_ferror(f, GOT_ERR_BAD_REF_DATA);
1006 			goto done;
1007 		}
1008 		err = parse_packed_ref_line(&ref, NULL, line);
1009 		free(line);
1010 		if (err)
1011 			goto done;
1012 		if (ref == NULL)
1013 			continue;
1014 
1015 		if (strcmp(ref->ref.ref.name, delref->ref.ref.name) == 0 &&
1016 		    memcmp(ref->ref.ref.sha1, delref->ref.ref.sha1,
1017 		    sizeof(delref->ref.ref.sha1)) == 0) {
1018 			found_delref = 1;
1019 			got_ref_close(ref);
1020 			continue;
1021 		}
1022 
1023 		err = insert_ref(&new, &refs, ref, repo);
1024 		if (err || new == NULL /* duplicate */)
1025 			got_ref_close(ref);
1026 		if (err)
1027 			goto done;
1028 	}
1029 
1030 	if (found_delref) {
1031 		struct got_reflist_entry *re;
1032 		size_t n;
1033 		struct stat sb;
1034 
1035 		n = fprintf(tmpf, "%s\n", GOT_PACKED_REFS_HEADER);
1036 		if (n != sizeof(GOT_PACKED_REFS_HEADER)) {
1037 			err = got_ferror(f, GOT_ERR_IO);
1038 			goto done;
1039 		}
1040 
1041 		SIMPLEQ_FOREACH(re, &refs, entry) {
1042 			uint8_t hex[SHA1_DIGEST_STRING_LENGTH];
1043 
1044 			if (got_sha1_digest_to_str(re->ref->ref.ref.sha1, hex,
1045 			    sizeof(hex)) == NULL) {
1046 				err = got_error(GOT_ERR_BAD_REF_DATA);
1047 				goto done;
1048 			}
1049 			n = fprintf(tmpf, "%s ", hex);
1050 			if (n != sizeof(hex)) {
1051 				err = got_ferror(f, GOT_ERR_IO);
1052 				goto done;
1053 			}
1054 			n = fprintf(tmpf, "%s\n", re->ref->ref.ref.name);
1055 			if (n != strlen(re->ref->ref.ref.name) + 1) {
1056 				err = got_ferror(f, GOT_ERR_IO);
1057 				goto done;
1058 			}
1059 		}
1060 
1061 		if (fflush(tmpf) != 0) {
1062 			err = got_error_from_errno("fflush");
1063 			goto done;
1064 		}
1065 
1066 		if (stat(packed_refs_path, &sb) != 0) {
1067 			if (errno != ENOENT) {
1068 				err = got_error_from_errno2("stat",
1069 				    packed_refs_path);
1070 				goto done;
1071 			}
1072 			sb.st_mode = GOT_DEFAULT_FILE_MODE;
1073 		}
1074 
1075 		if (rename(tmppath, packed_refs_path) != 0) {
1076 			err = got_error_from_errno3("rename", tmppath,
1077 			    packed_refs_path);
1078 			goto done;
1079 		}
1080 
1081 		if (chmod(packed_refs_path, sb.st_mode) != 0) {
1082 			err = got_error_from_errno2("chmod",
1083 			    packed_refs_path);
1084 			goto done;
1085 		}
1086 	}
1087 done:
1088 	if (delref->lf == NULL && lf)
1089 		unlock_err = got_lockfile_unlock(lf);
1090 	if (f) {
1091 		if (fclose(f) != 0 && err == NULL)
1092 			err = got_error_from_errno("fclose");
1093 	}
1094 	if (tmpf) {
1095 		unlink(tmppath);
1096 		if (fclose(tmpf) != 0 && err == NULL)
1097 			err = got_error_from_errno("fclose");
1098 	}
1099 	free(tmppath);
1100 	free(packed_refs_path);
1101 	got_ref_list_free(&refs);
1102 	return err ? err : unlock_err;
1103 }
1104 
1105 const struct got_error *
1106 got_ref_delete(struct got_reference *ref, struct got_repository *repo)
1107 {
1108 	const struct got_error *err = NULL, *unlock_err = NULL;
1109 	const char *name = got_ref_get_name(ref);
1110 	char *path_refs = NULL, *path = NULL;
1111 	struct got_lockfile *lf = NULL;
1112 
1113 	if (ref->flags & GOT_REF_IS_PACKED)
1114 		return delete_packed_ref(ref, repo);
1115 
1116 	path_refs = get_refs_dir_path(repo, name);
1117 	if (path_refs == NULL) {
1118 		err = got_error_from_errno2("get_refs_dir_path", name);
1119 		goto done;
1120 	}
1121 
1122 	if (asprintf(&path, "%s/%s", path_refs, name) == -1) {
1123 		err = got_error_from_errno("asprintf");
1124 		goto done;
1125 	}
1126 
1127 	if (ref->lf == NULL) {
1128 		err = got_lockfile_lock(&lf, path);
1129 		if (err)
1130 			goto done;
1131 	}
1132 
1133 	/* XXX: check if old content matches our expectations? */
1134 
1135 	if (unlink(path) != 0)
1136 		err = got_error_from_errno2("unlink", path);
1137 done:
1138 	if (ref->lf == NULL && lf)
1139 		unlock_err = got_lockfile_unlock(lf);
1140 
1141 	free(path_refs);
1142 	free(path);
1143 	return err ? err : unlock_err;
1144 }
1145 
1146 const struct got_error *
1147 got_ref_unlock(struct got_reference *ref)
1148 {
1149 	const struct got_error *err;
1150 	err = got_lockfile_unlock(ref->lf);
1151 	ref->lf = NULL;
1152 	return err;
1153 }