Gotweb

Blob

Date:: Sat Mar 17 17:13:19 2018 UTC
Message:: remove GOT_ERR_NO_MEM, we can just use errno in those cases
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_lib_worktree.h"
38 #include "got_lib_path.h"
39 #include "got_lib_sha1.h"
40 #include "got_lib_fileindex.h"
41 #include "got_lib_zbuf.h"
42 #include "got_lib_delta.h"
43 #include "got_lib_object.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_from_errno();
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_from_errno();
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_from_errno();
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 	char *absprefix = NULL;
162 
163 	if (!got_path_is_absolute(prefix)) {
164 		if (asprintf(&absprefix, "/%s", prefix) == -1)
165 			return got_error_from_errno();
166 	}
167 
168 	/* Create top-level directory (may already exist). */
169 	if (mkdir(path, GOT_DEFAULT_DIR_MODE) == -1 && errno != EEXIST) {
170 		err = got_error_from_errno();
171 		goto done;
172 	}
173 
174 	/* Create .got directory (may already exist). */
175 	if (asprintf(&path_got, "%s/%s", path, GOT_WORKTREE_GOT_DIR) == -1) {
176 		err = got_error_from_errno();
177 		goto done;
178 	}
179 	if (mkdir(path_got, GOT_DEFAULT_DIR_MODE) == -1 && errno != EEXIST) {
180 		err = got_error_from_errno();
181 		goto done;
182 	}
183 
184 	/* Create an empty lock file. */
185 	err = create_meta_file(path_got, GOT_WORKTREE_LOCK, NULL);
186 	if (err)
187 		goto done;
188 
189 	/* Create an empty file index. */
190 	err = create_meta_file(path_got, GOT_WORKTREE_FILE_INDEX, NULL);
191 	if (err)
192 		goto done;
193 
194 	/* Write the HEAD reference. */
195 	refstr = got_ref_to_str(head_ref);
196 	if (refstr == NULL) {
197 		err = got_error_from_errno();
198 		goto done;
199 	}
200 	err = create_meta_file(path_got, GOT_WORKTREE_HEAD, refstr);
201 	if (err)
202 		goto done;
203 
204 	/* Store path to repository. */
205 	repo_path = got_repo_get_path(repo);
206 	if (repo_path == NULL) {
207 		err = got_error_from_errno();
208 		goto done;
209 	}
210 	err = create_meta_file(path_got, GOT_WORKTREE_REPOSITORY, repo_path);
211 	if (err)
212 		goto done;
213 
214 	/* Store in-repository path prefix. */
215 	err = create_meta_file(path_got, GOT_WORKTREE_PATH_PREFIX,
216 	    absprefix ? absprefix : prefix);
217 	if (err)
218 		goto done;
219 
220 	/* Stamp work tree with format file. */
221 	if (asprintf(&formatstr, "%d", GOT_WORKTREE_FORMAT_VERSION) == -1) {
222 		err = got_error_from_errno();
223 		goto done;
224 	}
225 	err = create_meta_file(path_got, GOT_WORKTREE_FORMAT, formatstr);
226 	if (err)
227 		goto done;
228 
229 done:
230 	free(path_got);
231 	free(formatstr);
232 	free(refstr);
233 	free(repo_path);
234 	free(absprefix);
235 	return err;
236 }
237 
238 const struct got_error *
239 got_worktree_open(struct got_worktree **worktree, const char *path)
240 {
241 	const struct got_error *err = NULL;
242 	char *path_got;
243 	char *formatstr = NULL;
244 	char *path_lock = NULL;
245 	int version, fd = -1;
246 	const char *errstr;
247 
248 	*worktree = NULL;
249 
250 	if (asprintf(&path_got, "%s/%s", path, GOT_WORKTREE_GOT_DIR) == -1) {
251 		err = got_error_from_errno();
252 		path_got = NULL;
253 		goto done;
254 	}
255 
256 	if (asprintf(&path_lock, "%s/%s", path_got, GOT_WORKTREE_LOCK) == -1) {
257 		err = got_error_from_errno();
258 		path_lock = NULL;
259 		goto done;
260 	}
261 
262 	fd = open(path_lock, O_RDWR | O_EXLOCK | O_NONBLOCK);
263 	if (fd == -1) {
264 		err = (errno == EWOULDBLOCK ? got_error(GOT_ERR_WORKTREE_BUSY)
265 		    : got_error_from_errno());
266 		goto done;
267 	}
268 
269 	err = read_meta_file(&formatstr, path_got, GOT_WORKTREE_FORMAT);
270 	if (err)
271 		goto done;
272 
273 	version = strtonum(formatstr, 1, INT_MAX, &errstr);
274 	if (errstr) {
275 		err = got_error(GOT_ERR_WORKTREE_META);
276 		goto done;
277 	}
278 	if (version != GOT_WORKTREE_FORMAT_VERSION) {
279 		err = got_error(GOT_ERR_WORKTREE_VERS);
280 		goto done;
281 	}
282 
283 	*worktree = calloc(1, sizeof(**worktree));
284 	if (*worktree == NULL) {
285 		err = got_error_from_errno();
286 		goto done;
287 	}
288 	(*worktree)->lockfd = -1;
289 
290 	(*worktree)->root_path = strdup(path);
291 	if ((*worktree)->root_path == NULL) {
292 		err = got_error_from_errno();
293 		goto done;
294 	}
295 	err = read_meta_file(&(*worktree)->repo_path, path_got,
296 	    GOT_WORKTREE_REPOSITORY);
297 	if (err)
298 		goto done;
299 	err = read_meta_file(&(*worktree)->path_prefix, path_got,
300 	    GOT_WORKTREE_PATH_PREFIX);
301 	if (err)
302 		goto done;
303 
304 	err = read_meta_file(&(*worktree)->head_ref, path_got,
305 	    GOT_WORKTREE_HEAD);
306 	if (err)
307 		goto done;
308 
309 done:
310 	free(path_got);
311 	free(path_lock);
312 	if (err) {
313 		if (fd != -1)
314 			close(fd);
315 		if (*worktree != NULL)
316 			got_worktree_close(*worktree);
317 		*worktree = NULL;
318 	} else
319 		(*worktree)->lockfd = fd;
320 
321 	return err;
322 }
323 
324 void
325 got_worktree_close(struct got_worktree *worktree)
326 {
327 	free(worktree->root_path);
328 	free(worktree->repo_path);
329 	free(worktree->path_prefix);
330 	free(worktree->base_commit);
331 	free(worktree->head_ref);
332 	if (worktree->lockfd != -1)
333 		close(worktree->lockfd);
334 	free(worktree);
335 }
336 
337 char *
338 got_worktree_get_repo_path(struct got_worktree *worktree)
339 {
340 	return strdup(worktree->repo_path);
341 }
342 
343 char *
344 got_worktree_get_head_ref_name(struct got_worktree *worktree)
345 {
346 	return strdup(worktree->head_ref);
347 }
348 
349 static const struct got_error *
350 lock_worktree(struct got_worktree *worktree, int operation)
351 {
352 	if (flock(worktree->lockfd, operation | LOCK_NB) == -1)
353 		return (errno == EWOULDBLOCK ? got_error(GOT_ERR_WORKTREE_BUSY)
354 		    : got_error_from_errno());
355 	return NULL;
356 }
357 
358 static const char *
359 apply_path_prefix(struct got_worktree *worktree, const char *path)
360 {
361 	const char *p = path;
362 	p += strlen(worktree->path_prefix);
363 	if (*p == '/')
364 		p++;
365 	return p;
366 }
367 
368 static const struct got_error *
369 add_file_on_disk(struct got_worktree *worktree, struct got_fileindex *fileindex,
370    const char *path, struct got_blob_object *blob, struct got_repository *repo)
371 {
372 	const struct got_error *err = NULL;
373 	char *ondisk_path;
374 	int fd;
375 	size_t len, hdrlen;
376 	struct got_fileindex_entry *entry;
377 
378 	if (asprintf(&ondisk_path, "%s/%s", worktree->root_path,
379 	    apply_path_prefix(worktree, path)) == -1)
380 		return got_error_from_errno();
381 
382 	fd = open(ondisk_path, O_RDWR | O_CREAT | O_EXCL | O_NOFOLLOW,
383 	    GOT_DEFAULT_FILE_MODE);
384 	if (fd == -1) {
385 		err = got_error_from_errno();
386 		if (errno == EEXIST) {
387 			struct stat sb;
388 			if (lstat(ondisk_path, &sb) == -1) {
389 				err = got_error_from_errno();
390 			} else if (!S_ISREG(sb.st_mode)) {
391 				/* TODO file is obstructed; do something */
392 				err = got_error(GOT_ERR_FILE_OBSTRUCTED);
393 			}
394 		}
395 		return err;
396 	}
397 
398 	hdrlen = got_object_blob_get_hdrlen(blob);
399 	do {
400 		const uint8_t *buf = got_object_blob_get_read_buf(blob);
401 		err = got_object_blob_read_block(&len, blob);
402 		if (err)
403 			break;
404 		if (len > 0) {
405 			/* Skip blob object header first time around. */
406 			ssize_t outlen = write(fd, buf + hdrlen, len - hdrlen);
407 			hdrlen = 0;
408 			if (outlen == -1) {
409 				err = got_error_from_errno();
410 				break;
411 			} else if (outlen != len) {
412 				err = got_error(GOT_ERR_IO);
413 				break;
414 			}
415 		}
416 	} while (len != 0);
417 
418 	fsync(fd);
419 
420 	err = got_fileindex_entry_open(&entry, ondisk_path,
421 	    apply_path_prefix(worktree, path), blob->id.sha1);
422 	if (err)
423 		goto done;
424 
425 	err = got_fileindex_entry_add(fileindex, entry);
426 	if (err)
427 		goto done;
428 done:
429 	close(fd);
430 	free(ondisk_path);
431 	return err;
432 }
433 
434 static const struct got_error *
435 add_dir_on_disk(struct got_worktree *worktree, const char *path)
436 {
437 	const struct got_error *err = NULL;
438 	char *abspath;
439 
440 	if (asprintf(&abspath, "%s/%s", worktree->root_path,
441 	    apply_path_prefix(worktree, path)) == -1)
442 		return got_error_from_errno();
443 
444 	/* XXX queue work rather than editing disk directly? */
445 	if (mkdir(abspath, GOT_DEFAULT_DIR_MODE) == -1) {
446 		struct stat sb;
447 
448 		if (errno != EEXIST) {
449 			err = got_error_from_errno();
450 			goto done;
451 		}
452 
453 		if (lstat(abspath, &sb) == -1) {
454 			err = got_error_from_errno();
455 			goto done;
456 		}
457 
458 		if (!S_ISDIR(sb.st_mode)) {
459 			/* TODO directory is obstructed; do something */
460 			return got_error(GOT_ERR_FILE_OBSTRUCTED);
461 		}
462 	}
463 
464 done:
465 	free(abspath);
466 	return err;
467 }
468 
469 static const struct got_error *
470 tree_checkout(struct got_worktree *, struct got_fileindex *,
471     struct got_tree_object *, const char *, struct got_repository *,
472     got_worktree_checkout_cb progress_cb, void *progress_arg);
473 
474 static const struct got_error *
475 tree_checkout_entry(struct got_worktree *worktree,
476     struct got_fileindex *fileindex, struct got_tree_entry *te,
477     const char *parent, struct got_repository *repo,
478     got_worktree_checkout_cb progress_cb, void *progress_arg)
479 {
480 	const struct got_error *err = NULL;
481 	struct got_object *obj = NULL;
482 	struct got_blob_object *blob = NULL;
483 	struct got_tree_object *tree = NULL;
484 	char *path = NULL;
485 	size_t len;
486 
487 	if (parent[0] == '/' && parent[1] == '\0')
488 		parent = "";
489 	if (asprintf(&path, "%s/%s", parent, te->name) == -1)
490 		return got_error_from_errno();
491 
492 	/* Skip this entry if it is outside of our path prefix. */
493 	len = MIN(strlen(worktree->path_prefix), strlen(path));
494 	if (strncmp(path, worktree->path_prefix, len) != 0) {
495 		free(path);
496 		return NULL;
497 	}
498 
499 	err = got_object_open(&obj, repo, te->id);
500 	if (err)
501 		goto done;
502 
503 	(*progress_cb)(progress_arg, path);
504 
505 	switch (got_object_get_type(obj)) {
506 	case GOT_OBJ_TYPE_BLOB:
507 		if (strlen(worktree->path_prefix) >= strlen(path))
508 			break;
509 		err = got_object_blob_open(&blob, repo, obj, 8192);
510 		if (err)
511 			goto done;
512 		err = add_file_on_disk(worktree, fileindex, path, blob, repo);
513 		break;
514 	case GOT_OBJ_TYPE_TREE:
515 		err = got_object_tree_open(&tree, repo, obj);
516 		if (err)
517 			goto done;
518 		if (strlen(worktree->path_prefix) < strlen(path)) {
519 			err = add_dir_on_disk(worktree, path);
520 			if (err)
521 				break;
522 		}
523 		err = tree_checkout(worktree, fileindex, tree, path, repo,
524 		    progress_cb, progress_arg);
525 		break;
526 	default:
527 		break;
528 	}
529 
530 done:
531 	if (blob)
532 		got_object_blob_close(blob);
533 	if (tree)
534 		got_object_tree_close(tree);
535 	if (obj)
536 		got_object_close(obj);
537 	free(path);
538 	return err;
539 }
540 
541 static const struct got_error *
542 tree_checkout(struct got_worktree *worktree,
543     struct got_fileindex *fileindex, struct got_tree_object *tree,
544     const char *path, struct got_repository *repo,
545     got_worktree_checkout_cb progress_cb, void *progress_arg)
546 {
547 	const struct got_error *err = NULL;
548 	struct got_tree_entry *te;
549 	size_t len;
550 
551 	/* Skip this tree if it is outside of our path prefix. */
552 	len = MIN(strlen(worktree->path_prefix), strlen(path));
553 	if (strncmp(path, worktree->path_prefix, len) != 0)
554 		return NULL;
555 
556 	SIMPLEQ_FOREACH(te, &tree->entries, entry) {
557 		err = tree_checkout_entry(worktree, fileindex, te, path, repo,
558 		    progress_cb, progress_arg);
559 		if (err)
560 			break;
561 	}
562 
563 	return err;
564 }
565 
566 const struct got_error *
567 got_worktree_checkout_files(struct got_worktree *worktree,
568     struct got_reference *head_ref, struct got_repository *repo,
569     got_worktree_checkout_cb progress_cb, void *progress_arg)
570 {
571 	const struct got_error *err = NULL, *unlockerr;
572 	struct got_object_id *commit_id = NULL;
573 	struct got_object *obj = NULL;
574 	struct got_commit_object *commit = NULL;
575 	struct got_tree_object *tree = NULL;
576 	char *fileindex_path = NULL, *new_fileindex_path = NULL;
577 	struct got_fileindex *fileindex = NULL;
578 	FILE *findex = NULL;
579 
580 	err = lock_worktree(worktree, LOCK_EX);
581 	if (err)
582 		return err;
583 
584 	fileindex = got_fileindex_open();
585 	if (fileindex == NULL) {
586 		err = got_error_from_errno();
587 		goto done;
588 	}
589 
590 	if (asprintf(&fileindex_path, "%s/%s/%s", worktree->root_path,
591 	    GOT_WORKTREE_GOT_DIR, GOT_WORKTREE_FILE_INDEX) == -1) {
592 		err = got_error_from_errno();
593 		fileindex_path = NULL;
594 		goto done;
595 	}
596 
597 	err = got_opentemp_named(&new_fileindex_path, &findex, fileindex_path);
598 	if (err)
599 		goto done;
600 
601 	err = got_ref_resolve(&commit_id, repo, head_ref);
602 	if (err)
603 		goto done;
604 
605 	err = got_object_open(&obj, repo, commit_id);
606 	if (err)
607 		goto done;
608 
609 	if (got_object_get_type(obj) != GOT_OBJ_TYPE_COMMIT) {
610 		err = got_error(GOT_ERR_OBJ_TYPE);
611 		goto done;
612 	}
613 
614 	err = got_object_commit_open(&commit, repo, obj);
615 	if (err)
616 		goto done;
617 
618 	got_object_close(obj);
619 	err = got_object_open(&obj, repo, commit->tree_id);
620 	if (err)
621 		goto done;
622 
623 	if (got_object_get_type(obj) != GOT_OBJ_TYPE_TREE) {
624 		err = got_error(GOT_ERR_OBJ_TYPE);
625 		goto done;
626 	}
627 
628 	err = got_object_tree_open(&tree, repo, obj);
629 	if (err)
630 		goto done;
631 
632 	err = tree_checkout(worktree, fileindex, tree, "/", repo,
633 	    progress_cb, progress_arg);
634 	if (err)
635 		goto done;
636 
637 	err = got_fileindex_write(fileindex, findex);
638 	if (err)
639 		goto done;
640 
641 	if (rename(new_fileindex_path, fileindex_path) != 0) {
642 		err = got_error_from_errno();
643 		goto done;
644 	}
645 
646 	free(new_fileindex_path);
647 	new_fileindex_path = NULL;
648 
649 done:
650 	if (commit)
651 		got_object_commit_close(commit);
652 	if (obj)
653 		got_object_close(obj);
654 	free(commit_id);
655 	if (new_fileindex_path)
656 		unlink(new_fileindex_path);
657 	if (findex)
658 		fclose(findex);
659 	free(new_fileindex_path);
660 	free(fileindex_path);
661 	got_fileindex_close(fileindex);
662 	unlockerr = lock_worktree(worktree, LOCK_SH);
663 	if (unlockerr && err == NULL)
664 		err = unlockerr;
665 	return err;
666 }