Gotweb

Blob

Date:: Mon Mar 12 12:37:17 2018 UTC
Message:: remove base-commit meta file; this will move into the fileindex
Actions:: History | Blame | Raw File
1 /*
2  * Copyright (c) 2018 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/stat.h>
18 #include <sys/limits.h>
19 #include <sys/queue.h>
20 
21 #include <string.h>
22 #include <stdio.h>
23 #include <stdlib.h>
24 #include <fcntl.h>
25 #include <errno.h>
26 #include <unistd.h>
27 #include <sha1.h>
28 #include <zlib.h>
29 #include <fnmatch.h>
30 
31 #include "got_error.h"
32 #include "got_repository.h"
33 #include "got_refs.h"
34 #include "got_object.h"
35 #include "got_worktree.h"
36 
37 #include "got_worktree_lib.h"
38 #include "got_path_lib.h"
39 #include "got_sha1_lib.h"
40 #include "got_fileindex_lib.h"
41 #include "got_zbuf_lib.h"
42 #include "got_delta_lib.h"
43 #include "got_object_lib.h"
44 
45 #ifndef MIN
46 #define	MIN(_a,_b) ((_a) < (_b) ? (_a) : (_b))
47 #endif
48 
49 static const struct got_error *
50 create_meta_file(const char *path_got, const char *name, const char *content)
51 {
52 	const struct got_error *err = NULL;
53 	char *path;
54 	int fd = -1;
55 	char buf[4];
56 	ssize_t n;
57 
58 	if (asprintf(&path, "%s/%s", path_got, name) == -1) {
59 		err = got_error(GOT_ERR_NO_MEM);
60 		path = NULL;
61 		goto done;
62 	}
63 
64 	fd = open(path, O_RDWR | O_CREAT | O_EXCL | O_NOFOLLOW,
65 	    GOT_DEFAULT_FILE_MODE);
66 	if (fd == -1) {
67 		err = got_error_from_errno();
68 		goto done;
69 	}
70 
71 	/* The file should be empty. */
72 	n = read(fd, buf, sizeof(buf));
73 	if (n != 0) {
74 		err = (n == -1 ? got_error_from_errno() :
75 		    got_error(GOT_ERR_WORKTREE_EXISTS));
76 		goto done;
77 	}
78 
79 	if (content) {
80 		int len = dprintf(fd, "%s\n", content);
81 		if (len != strlen(content) + 1) {
82 			err = got_error_from_errno();
83 			goto done;
84 		}
85 	}
86 
87 done:
88 	if (fd != -1 && close(fd) == -1 && err == NULL)
89 		err = got_error_from_errno();
90 	free(path);
91 	return err;
92 }
93 
94 static const struct got_error *
95 read_meta_file(char **content, const char *path_got, const char *name)
96 {
97 	const struct got_error *err = NULL;
98 	char *path;
99 	int fd = -1;
100 	ssize_t n;
101 	struct stat sb;
102 
103 	*content = NULL;
104 
105 	if (asprintf(&path, "%s/%s", path_got, name) == -1) {
106 		err = got_error(GOT_ERR_NO_MEM);
107 		path = NULL;
108 		goto done;
109 	}
110 
111 	fd = open(path, O_RDONLY | O_NOFOLLOW);
112 	if (fd == -1) {
113 		err = got_error_from_errno();
114 		goto done;
115 	}
116 	if (flock(fd, LOCK_SH | LOCK_NB) == -1) {
117 		err = (errno == EWOULDBLOCK ? got_error(GOT_ERR_WORKTREE_BUSY)
118 		    : got_error_from_errno());
119 		goto done;
120 	}
121 
122 	stat(path, &sb);
123 	*content = calloc(1, sb.st_size);
124 	if (*content == NULL) {
125 		err = got_error(GOT_ERR_NO_MEM);
126 		goto done;
127 	}
128 
129 	n = read(fd, *content, sb.st_size);
130 	if (n != sb.st_size) {
131 		err = (n == -1 ? got_error_from_errno() :
132 		    got_error(GOT_ERR_WORKTREE_META));
133 		goto done;
134 	}
135 	if ((*content)[sb.st_size - 1] != '\n') {
136 		err = got_error(GOT_ERR_WORKTREE_META);
137 		goto done;
138 	}
139 	(*content)[sb.st_size - 1] = '\0';
140 
141 done:
142 	if (fd != -1 && close(fd) == -1 && err == NULL)
143 		err = got_error_from_errno();
144 	free(path);
145 	if (err) {
146 		free(*content);
147 		*content = NULL;
148 	}
149 	return err;
150 }
151 
152 const struct got_error *
153 got_worktree_init(const char *path, struct got_reference *head_ref,
154     const char *prefix, struct got_repository *repo)
155 {
156 	const struct got_error *err = NULL;
157 	char *path_got = NULL;
158 	char *refstr = NULL;
159 	char *repo_path = NULL;
160 	char *formatstr = NULL;
161 
162 	if (!got_path_is_absolute(prefix))
163 		return got_error(GOT_ERR_BAD_PATH);
164 
165 	/* Create top-level directory (may already exist). */
166 	if (mkdir(path, GOT_DEFAULT_DIR_MODE) == -1 && errno != EEXIST) {
167 		err = got_error_from_errno();
168 		goto done;
169 	}
170 
171 	/* Create .got directory (may already exist). */
172 	if (asprintf(&path_got, "%s/%s", path, GOT_WORKTREE_GOT_DIR) == -1) {
173 		err = got_error(GOT_ERR_NO_MEM);
174 		goto done;
175 	}
176 	if (mkdir(path_got, GOT_DEFAULT_DIR_MODE) == -1 && errno != EEXIST) {
177 		err = got_error_from_errno();
178 		goto done;
179 	}
180 
181 	/* Create an empty lock file. */
182 	err = create_meta_file(path_got, GOT_WORKTREE_LOCK, NULL);
183 	if (err)
184 		goto done;
185 
186 	/* Create an empty file index. */
187 	err = create_meta_file(path_got, GOT_WORKTREE_FILE_INDEX, NULL);
188 	if (err)
189 		goto done;
190 
191 	/* Write the HEAD reference. */
192 	refstr = got_ref_to_str(head_ref);
193 	if (refstr == NULL) {
194 		err = got_error(GOT_ERR_NO_MEM);
195 		goto done;
196 	}
197 	err = create_meta_file(path_got, GOT_WORKTREE_HEAD, refstr);
198 	if (err)
199 		goto done;
200 
201 	/* Store path to repository. */
202 	repo_path = got_repo_get_path(repo);
203 	if (repo_path == NULL) {
204 		err = got_error(GOT_ERR_NO_MEM);
205 		goto done;
206 	}
207 	err = create_meta_file(path_got, GOT_WORKTREE_REPOSITORY, repo_path);
208 	if (err)
209 		goto done;
210 
211 	/* Store in-repository path prefix. */
212 	err = create_meta_file(path_got, GOT_WORKTREE_PATH_PREFIX, prefix);
213 	if (err)
214 		goto done;
215 
216 	/* Stamp work tree with format file. */
217 	if (asprintf(&formatstr, "%d", GOT_WORKTREE_FORMAT_VERSION) == -1) {
218 		err = got_error(GOT_ERR_NO_MEM);
219 		goto done;
220 	}
221 	err = create_meta_file(path_got, GOT_WORKTREE_FORMAT, formatstr);
222 	if (err)
223 		goto done;
224 
225 done:
226 	free(path_got);
227 	free(formatstr);
228 	free(refstr);
229 	free(repo_path);
230 	return err;
231 }
232 
233 const struct got_error *
234 got_worktree_open(struct got_worktree **worktree, const char *path)
235 {
236 	const struct got_error *err = NULL;
237 	char *path_got;
238 	char *refstr = NULL;
239 	char *formatstr = NULL;
240 	char *path_lock = NULL;
241 	int version, fd = -1;
242 	const char *errstr;
243 
244 	*worktree = NULL;
245 
246 	if (asprintf(&path_got, "%s/%s", path, GOT_WORKTREE_GOT_DIR) == -1) {
247 		err = got_error(GOT_ERR_NO_MEM);
248 		path_got = NULL;
249 		goto done;
250 	}
251 
252 	if (asprintf(&path_lock, "%s/%s", path_got, GOT_WORKTREE_LOCK) == -1) {
253 		err = got_error(GOT_ERR_NO_MEM);
254 		path_lock = NULL;
255 		goto done;
256 	}
257 
258 	fd = open(path_lock, O_RDWR | O_EXLOCK | O_NONBLOCK);
259 	if (fd == -1) {
260 		err = (errno == EWOULDBLOCK ? got_error(GOT_ERR_WORKTREE_BUSY)
261 		    : got_error_from_errno());
262 		goto done;
263 	}
264 
265 	err = read_meta_file(&formatstr, path_got, GOT_WORKTREE_FORMAT);
266 	if (err)
267 		goto done;
268 
269 	version = strtonum(formatstr, 1, INT_MAX, &errstr);
270 	if (errstr) {
271 		err = got_error(GOT_ERR_WORKTREE_META);
272 		goto done;
273 	}
274 	if (version != GOT_WORKTREE_FORMAT_VERSION) {
275 		err = got_error(GOT_ERR_WORKTREE_VERS);
276 		goto done;
277 	}
278 
279 	*worktree = calloc(1, sizeof(**worktree));
280 	if (*worktree == NULL) {
281 		err = got_error(GOT_ERR_NO_MEM);
282 		goto done;
283 	}
284 	(*worktree)->lockfd = -1;
285 
286 	(*worktree)->root_path = strdup(path);
287 	if ((*worktree)->root_path == NULL) {
288 		err = got_error(GOT_ERR_NO_MEM);
289 		goto done;
290 	}
291 	err = read_meta_file(&(*worktree)->repo_path, path_got,
292 	    GOT_WORKTREE_REPOSITORY);
293 	if (err)
294 		goto done;
295 	err = read_meta_file(&(*worktree)->path_prefix, path_got,
296 	    GOT_WORKTREE_PATH_PREFIX);
297 	if (err)
298 		goto done;
299 
300 	err = read_meta_file(&(*worktree)->head_ref, path_got,
301 	    GOT_WORKTREE_HEAD);
302 	if (err)
303 		goto done;
304 
305 done:
306 	free(path_got);
307 	free(path_lock);
308 	if (err) {
309 		if (fd != -1)
310 			close(fd);
311 		if (*worktree != NULL)
312 			got_worktree_close(*worktree);
313 		*worktree = NULL;
314 	} else
315 		(*worktree)->lockfd = fd;
316 
317 	return err;
318 }
319 
320 void
321 got_worktree_close(struct got_worktree *worktree)
322 {
323 	free(worktree->root_path);
324 	free(worktree->repo_path);
325 	free(worktree->path_prefix);
326 	free(worktree->base_commit);
327 	free(worktree->head_ref);
328 	if (worktree->lockfd != -1)
329 		close(worktree->lockfd);
330 	free(worktree);
331 }
332 
333 char *
334 got_worktree_get_repo_path(struct got_worktree *worktree)
335 {
336 	return strdup(worktree->repo_path);
337 }
338 
339 char *
340 got_worktree_get_head_ref_name(struct got_worktree *worktree)
341 {
342 	return strdup(worktree->head_ref);
343 }
344 
345 static const struct got_error *
346 lock_worktree(struct got_worktree *worktree, int operation)
347 {
348 	if (flock(worktree->lockfd, operation | LOCK_NB) == -1)
349 		return (errno == EWOULDBLOCK ? got_error(GOT_ERR_WORKTREE_BUSY)
350 		    : got_error_from_errno());
351 	return NULL;
352 }
353 
354 static const char *
355 apply_path_prefix(struct got_worktree *worktree, const char *path)
356 {
357 	const char *p = path;
358 	p += strlen(worktree->path_prefix);
359 	if (*p == '/')
360 		p++;
361 	return p;
362 }
363 
364 static const struct got_error *
365 add_file_on_disk(struct got_worktree *worktree, struct got_fileindex *fileindex,
366    const char *path, struct got_blob_object *blob, struct got_repository *repo)
367 {
368 	const struct got_error *err = NULL;
369 	char *ondisk_path;
370 	int fd;
371 	size_t len, hdrlen;
372 	struct got_fileindex_entry *entry;
373 
374 	if (asprintf(&ondisk_path, "%s/%s", worktree->root_path,
375 	    apply_path_prefix(worktree, path)) == -1)
376 		return got_error(GOT_ERR_NO_MEM);
377 
378 	fd = open(ondisk_path, O_RDWR | O_CREAT | O_EXCL | O_NOFOLLOW,
379 	    GOT_DEFAULT_FILE_MODE);
380 	if (fd == -1) {
381 		err = got_error_from_errno();
382 		if (errno == EEXIST) {
383 			struct stat sb;
384 			if (lstat(ondisk_path, &sb) == -1) {
385 				err = got_error_from_errno();
386 			} else if (!S_ISREG(sb.st_mode)) {
387 				/* TODO file is obstructed; do something */
388 				err = got_error(GOT_ERR_FILE_OBSTRUCTED);
389 			}
390 		}
391 		return err;
392 	}
393 
394 	hdrlen = got_object_blob_get_hdrlen(blob);
395 	do {
396 		const uint8_t *buf = got_object_blob_get_read_buf(blob);
397 		err = got_object_blob_read_block(&len, blob);
398 		if (err)
399 			break;
400 		if (len > 0) {
401 			/* Skip blob object header first time around. */
402 			ssize_t outlen = write(fd, buf + hdrlen, len - hdrlen);
403 			hdrlen = 0;
404 			if (outlen == -1) {
405 				err = got_error_from_errno();
406 				break;
407 			} else if (outlen != len) {
408 				err = got_error(GOT_ERR_IO);
409 				break;
410 			}
411 		}
412 	} while (len != 0);
413 
414 	fsync(fd);
415 
416 	err = got_fileindex_entry_open(&entry, ondisk_path,
417 	    apply_path_prefix(worktree, path), blob->id.sha1);
418 	if (err)
419 		goto done;
420 
421 	err = got_fileindex_entry_add(fileindex, entry);
422 	if (err)
423 		goto done;
424 done:
425 	close(fd);
426 	free(ondisk_path);
427 	return err;
428 }
429 
430 static const struct got_error *
431 add_dir_on_disk(struct got_worktree *worktree, const char *path)
432 {
433 	const struct got_error *err = NULL;
434 	char *abspath;
435 	size_t len;
436 
437 	if (asprintf(&abspath, "%s/%s", worktree->root_path,
438 	    apply_path_prefix(worktree, path)) == -1)
439 		return got_error(GOT_ERR_NO_MEM);
440 
441 	/* XXX queue work rather than editing disk directly? */
442 	if (mkdir(abspath, GOT_DEFAULT_DIR_MODE) == -1) {
443 		struct stat sb;
444 
445 		if (errno != EEXIST) {
446 			err = got_error_from_errno();
447 			goto done;
448 		}
449 
450 		if (lstat(abspath, &sb) == -1) {
451 			err = got_error_from_errno();
452 			goto done;
453 		}
454 
455 		if (!S_ISDIR(sb.st_mode)) {
456 			/* TODO directory is obstructed; do something */
457 			return got_error(GOT_ERR_FILE_OBSTRUCTED);
458 		}
459 	}
460 
461 done:
462 	free(abspath);
463 	return err;
464 }
465 
466 static const struct got_error *
467 tree_checkout(struct got_worktree *, struct got_fileindex *,
468     struct got_tree_object *, const char *, struct got_repository *);
469 
470 static const struct got_error *
471 tree_checkout_entry(struct got_worktree *worktree,
472     struct got_fileindex *fileindex, struct got_tree_entry *te,
473     const char *parent, struct got_repository *repo)
474 {
475 	const struct got_error *err = NULL;
476 	struct got_object *obj = NULL;
477 	struct got_blob_object *blob = NULL;
478 	struct got_tree_object *tree = NULL;
479 	char *path = NULL;
480 	size_t len;
481 
482 	if (parent[0] == '/' && parent[1] == '\0')
483 		parent = "";
484 	if (asprintf(&path, "%s/%s", parent, te->name) == -1)
485 		return got_error(GOT_ERR_NO_MEM);
486 
487 	/* Skip this entry if it is outside of our path prefix. */
488 	len = MIN(strlen(worktree->path_prefix), strlen(path));
489 	if (strncmp(path, worktree->path_prefix, len) != 0) {
490 		free(path);
491 		return NULL;
492 	}
493 
494 	err = got_object_open(&obj, repo, te->id);
495 	if (err)
496 		goto done;
497 
498 	switch (got_object_get_type(obj)) {
499 	case GOT_OBJ_TYPE_BLOB:
500 		if (strlen(worktree->path_prefix) >= strlen(path))
501 			break;
502 		err = got_object_blob_open(&blob, repo, obj, 8192);
503 		if (err)
504 			goto done;
505 		err = add_file_on_disk(worktree, fileindex, path, blob, repo);
506 		break;
507 	case GOT_OBJ_TYPE_TREE:
508 		err = got_object_tree_open(&tree, repo, obj);
509 		if (err)
510 			goto done;
511 		if (strlen(worktree->path_prefix) < strlen(path)) {
512 			err = add_dir_on_disk(worktree, path);
513 			if (err)
514 				break;
515 		}
516 		err = tree_checkout(worktree, fileindex, tree, path, repo);
517 		break;
518 	default:
519 		break;
520 	}
521 
522 done:
523 	if (blob)
524 		got_object_blob_close(blob);
525 	if (tree)
526 		got_object_tree_close(tree);
527 	if (obj)
528 		got_object_close(obj);
529 	free(path);
530 	return err;
531 }
532 
533 static const struct got_error *
534 tree_checkout(struct got_worktree *worktree,
535     struct got_fileindex *fileindex, struct got_tree_object *tree,
536     const char *path, struct got_repository *repo)
537 {
538 	const struct got_error *err = NULL;
539 	struct got_tree_entry *te;
540 	size_t len;
541 
542 	/* Skip this tree if it is outside of our path prefix. */
543 	len = MIN(strlen(worktree->path_prefix), strlen(path));
544 	if (strncmp(path, worktree->path_prefix, len) != 0)
545 		return NULL;
546 
547 	SIMPLEQ_FOREACH(te, &tree->entries, entry) {
548 		err = tree_checkout_entry(worktree, fileindex, te, path, repo);
549 		if (err)
550 			break;
551 	}
552 
553 	return err;
554 }
555 
556 const struct got_error *
557 got_worktree_checkout_files(struct got_worktree *worktree,
558     struct got_reference *head_ref, struct got_repository *repo)
559 {
560 	const struct got_error *err = NULL, *unlockerr;
561 	struct got_object_id *commit_id = NULL;
562 	struct got_object *obj = NULL;
563 	struct got_commit_object *commit = NULL;
564 	struct got_tree_object *tree = NULL;
565 	char *fileindex_path = NULL, *new_fileindex_path = NULL;
566 	struct got_fileindex *fileindex = NULL;
567 	FILE *findex = NULL;
568 
569 	err = lock_worktree(worktree, LOCK_EX);
570 	if (err)
571 		return err;
572 
573 	fileindex = got_fileindex_open();
574 	if (fileindex == NULL) {
575 		err = got_error(GOT_ERR_NO_MEM);
576 		goto done;
577 	}
578 
579 	err = got_opentemp_named(&new_fileindex_path, &findex, fileindex_path);
580 	if (err)
581 		goto done;
582 
583 
584 	if (asprintf(&fileindex_path, "%s/%s/%s", worktree->root_path,
585 	    GOT_WORKTREE_GOT_DIR, GOT_WORKTREE_FILE_INDEX) == -1) {
586 		err = got_error(GOT_ERR_NO_MEM);
587 		fileindex_path = NULL;
588 		goto done;
589 	}
590 
591 	err = got_ref_resolve(&commit_id, repo, head_ref);
592 	if (err)
593 		goto done;
594 
595 	err = got_object_open(&obj, repo, commit_id);
596 	if (err)
597 		goto done;
598 
599 	if (got_object_get_type(obj) != GOT_OBJ_TYPE_COMMIT) {
600 		err = got_error(GOT_ERR_OBJ_TYPE);
601 		goto done;
602 	}
603 
604 	err = got_object_commit_open(&commit, repo, obj);
605 	if (err)
606 		goto done;
607 
608 	got_object_close(obj);
609 	err = got_object_open(&obj, repo, commit->tree_id);
610 	if (err)
611 		goto done;
612 
613 	if (got_object_get_type(obj) != GOT_OBJ_TYPE_TREE) {
614 		err = got_error(GOT_ERR_OBJ_TYPE);
615 		goto done;
616 	}
617 
618 	err = got_object_tree_open(&tree, repo, obj);
619 	if (err)
620 		goto done;
621 
622 	err = tree_checkout(worktree, fileindex, tree, "/", repo);
623 	if (err)
624 		goto done;
625 
626 	err = got_fileindex_write(fileindex, findex);
627 	if (err)
628 		goto done;
629 
630 	if (rename(new_fileindex_path, fileindex_path) != 0) {
631 		err = got_error_from_errno();
632 		goto done;
633 	}
634 
635 	free(new_fileindex_path);
636 	new_fileindex_path = NULL;
637 
638 done:
639 	if (commit)
640 		got_object_commit_close(commit);
641 	if (obj)
642 		got_object_close(obj);
643 	free(commit_id);
644 	if (new_fileindex_path)
645 		unlink(new_fileindex_path);
646 	if (findex)
647 		fclose(findex);
648 	free(new_fileindex_path);
649 	free(fileindex_path);
650 	got_fileindex_close(fileindex);
651 	unlockerr = lock_worktree(worktree, LOCK_SH);
652 	if (unlockerr && err == NULL)
653 		err = unlockerr;
654 	return err;
655 }