summaryrefslogtreecommitdiff
path: root/src/libgit2/clone.c
blob: 1843875f8e541f6fff5cf3af83c9fb73173aeab2 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
/*
 * Copyright (C) the libgit2 contributors. All rights reserved.
 *
 * This file is part of libgit2, distributed under the GNU GPL v2 with
 * a Linking Exception. For full terms see the included COPYING file.
 */

#include "clone.h"

#include "git2/clone.h"
#include "git2/remote.h"
#include "git2/revparse.h"
#include "git2/branch.h"
#include "git2/config.h"
#include "git2/checkout.h"
#include "git2/commit.h"
#include "git2/tree.h"

#include "remote.h"
#include "futils.h"
#include "refs.h"
#include "fs_path.h"
#include "repository.h"
#include "odb.h"

static int clone_local_into(git_repository *repo, git_remote *remote, const git_fetch_options *fetch_opts, const git_checkout_options *co_opts, const char *branch, int link);

static int create_branch(
	git_reference **branch,
	git_repository *repo,
	const git_oid *target,
	const char *name,
	const char *log_message)
{
	git_commit *head_obj = NULL;
	git_reference *branch_ref = NULL;
	git_str refname = GIT_STR_INIT;
	int error;

	/* Find the target commit */
	if ((error = git_commit_lookup(&head_obj, repo, target)) < 0)
		return error;

	/* Create the new branch */
	if ((error = git_str_printf(&refname, GIT_REFS_HEADS_DIR "%s", name)) < 0)
		return error;

	error = git_reference_create(&branch_ref, repo, git_str_cstr(&refname), target, 0, log_message);
	git_str_dispose(&refname);
	git_commit_free(head_obj);

	if (!error)
		*branch = branch_ref;
	else
		git_reference_free(branch_ref);

	return error;
}

static int setup_tracking_config(
	git_repository *repo,
	const char *branch_name,
	const char *remote_name,
	const char *merge_target)
{
	git_config *cfg;
	git_str remote_key = GIT_STR_INIT, merge_key = GIT_STR_INIT;
	int error = -1;

	if (git_repository_config__weakptr(&cfg, repo) < 0)
		return -1;

	if (git_str_printf(&remote_key, "branch.%s.remote", branch_name) < 0)
		goto cleanup;

	if (git_str_printf(&merge_key, "branch.%s.merge", branch_name) < 0)
		goto cleanup;

	if (git_config_set_string(cfg, git_str_cstr(&remote_key), remote_name) < 0)
		goto cleanup;

	if (git_config_set_string(cfg, git_str_cstr(&merge_key), merge_target) < 0)
		goto cleanup;

	error = 0;

cleanup:
	git_str_dispose(&remote_key);
	git_str_dispose(&merge_key);
	return error;
}

static int create_tracking_branch(
	git_reference **branch,
	git_repository *repo,
	const git_oid *target,
	const char *branch_name,
	const char *log_message)
{
	int error;

	if ((error = create_branch(branch, repo, target, branch_name, log_message)) < 0)
		return error;

	return setup_tracking_config(
		repo,
		branch_name,
		GIT_REMOTE_ORIGIN,
		git_reference_name(*branch));
}

static int update_head_to_new_branch(
	git_repository *repo,
	const git_oid *target,
	const char *name,
	const char *reflog_message)
{
	git_reference *tracking_branch = NULL;
	int error;

	if (!git__prefixcmp(name, GIT_REFS_HEADS_DIR))
		name += strlen(GIT_REFS_HEADS_DIR);

	error = create_tracking_branch(&tracking_branch, repo, target, name,
			reflog_message);

	if (!error)
		error = git_repository_set_head(
			repo, git_reference_name(tracking_branch));

	git_reference_free(tracking_branch);

	/* if it already existed, then the user's refspec created it for us, ignore it' */
	if (error == GIT_EEXISTS)
		error = 0;

	return error;
}

static int update_head_to_default(git_repository *repo)
{
	git_str initialbranch = GIT_STR_INIT;
	const char *branch_name;
	int error = 0;

	if ((error = git_repository_initialbranch(&initialbranch, repo)) < 0)
		goto done;

	if (git__prefixcmp(initialbranch.ptr, GIT_REFS_HEADS_DIR) != 0) {
		git_error_set(GIT_ERROR_INVALID, "invalid initial branch '%s'", initialbranch.ptr);
		error = -1;
		goto done;
	}

	branch_name = initialbranch.ptr + strlen(GIT_REFS_HEADS_DIR);

	error = setup_tracking_config(repo, branch_name, GIT_REMOTE_ORIGIN,
		initialbranch.ptr);

done:
	git_str_dispose(&initialbranch);
	return error;
}

static int update_remote_head(
	git_repository *repo,
	git_remote *remote,
	git_str *target,
	const char *reflog_message)
{
	git_refspec *refspec;
	git_reference *remote_head = NULL;
	git_str remote_head_name = GIT_STR_INIT;
	git_str remote_branch_name = GIT_STR_INIT;
	int error;

	/* Determine the remote tracking ref name from the local branch */
	refspec = git_remote__matching_refspec(remote, git_str_cstr(target));

	if (refspec == NULL) {
		git_error_set(GIT_ERROR_NET, "the remote's default branch does not fit the refspec configuration");
		error = GIT_EINVALIDSPEC;
		goto cleanup;
	}

	if ((error = git_refspec__transform(
		&remote_branch_name,
		refspec,
		git_str_cstr(target))) < 0)
		goto cleanup;

	if ((error = git_str_printf(&remote_head_name,
		"%s%s/%s",
		GIT_REFS_REMOTES_DIR,
		git_remote_name(remote),
		GIT_HEAD_FILE)) < 0)
		goto cleanup;

	error = git_reference_symbolic_create(
		&remote_head,
		repo,
		git_str_cstr(&remote_head_name),
		git_str_cstr(&remote_branch_name),
		true,
		reflog_message);

cleanup:
	git_reference_free(remote_head);
	git_str_dispose(&remote_branch_name);
	git_str_dispose(&remote_head_name);
	return error;
}

static int update_head_to_remote(
		git_repository *repo,
		git_remote *remote,
		const char *reflog_message)
{
	int error = 0;
	size_t refs_len;
	const git_remote_head *remote_head, **refs;
	const git_oid *remote_head_id;
	git_str branch = GIT_STR_INIT;

	if ((error = git_remote_ls(&refs, &refs_len, remote)) < 0)
		return error;

	/* We cloned an empty repository or one with an unborn HEAD */
	if (refs_len == 0 || strcmp(refs[0]->name, GIT_HEAD_FILE))
		return update_head_to_default(repo);

	/* We know we have HEAD, let's see where it points */
	remote_head = refs[0];
	GIT_ASSERT(remote_head);

	remote_head_id = &remote_head->oid;

	error = git_remote__default_branch(&branch, remote);
	if (error == GIT_ENOTFOUND) {
		error = git_repository_set_head_detached(
			repo, remote_head_id);
		goto cleanup;
	}

	if ((error = update_remote_head(repo, remote, &branch, reflog_message)) < 0)
		goto cleanup;

	error = update_head_to_new_branch(
		repo,
		remote_head_id,
		git_str_cstr(&branch),
		reflog_message);

cleanup:
	git_str_dispose(&branch);

	return error;
}

static int update_head_to_branch(
		git_repository *repo,
		git_remote *remote,
		const char *branch,
		const char *reflog_message)
{
	int retcode;
	git_str remote_branch_name = GIT_STR_INIT;
	git_reference *remote_ref = NULL;
	git_str default_branch = GIT_STR_INIT;

	GIT_ASSERT_ARG(remote);
	GIT_ASSERT_ARG(branch);

	if ((retcode = git_str_printf(&remote_branch_name, GIT_REFS_REMOTES_DIR "%s/%s",
		git_remote_name(remote), branch)) < 0 )
		goto cleanup;

	if ((retcode = git_reference_lookup(&remote_ref, repo, git_str_cstr(&remote_branch_name))) < 0)
		goto cleanup;

	if ((retcode = update_head_to_new_branch(repo, git_reference_target(remote_ref), branch,
			reflog_message)) < 0)
		goto cleanup;

	if ((retcode = git_remote__default_branch(&default_branch, remote)) < 0)
		goto cleanup;

	if (!git_remote__matching_refspec(remote, git_str_cstr(&default_branch)))
		goto cleanup;

	retcode = update_remote_head(repo, remote, &default_branch, reflog_message);

cleanup:
	git_reference_free(remote_ref);
	git_str_dispose(&remote_branch_name);
	git_str_dispose(&default_branch);
	return retcode;
}

static int default_repository_create(git_repository **out, const char *path, int bare, void *payload)
{
	GIT_UNUSED(payload);

	return git_repository_init(out, path, bare);
}

static int default_remote_create(
		git_remote **out,
		git_repository *repo,
		const char *name,
		const char *url,
		void *payload)
{
	GIT_UNUSED(payload);

	return git_remote_create(out, repo, name, url);
}

/*
 * submodules?
 */

static int create_and_configure_origin(
		git_remote **out,
		git_repository *repo,
		const char *url,
		const git_clone_options *options)
{
	int error;
	git_remote *origin = NULL;
	char buf[GIT_PATH_MAX];
	git_remote_create_cb remote_create = options->remote_cb;
	void *payload = options->remote_cb_payload;

	/* If the path exists and is a dir, the url should be the absolute path */
	if (git_fs_path_root(url) < 0 && git_fs_path_exists(url) && git_fs_path_isdir(url)) {
		if (p_realpath(url, buf) == NULL)
			return -1;

		url = buf;
	}

	if (!remote_create) {
		remote_create = default_remote_create;
		payload = NULL;
	}

	if ((error = remote_create(&origin, repo, "origin", url, payload)) < 0)
		goto on_error;

	*out = origin;
	return 0;

on_error:
	git_remote_free(origin);
	return error;
}

static bool should_checkout(
	git_repository *repo,
	bool is_bare,
	const git_checkout_options *opts)
{
	if (is_bare)
		return false;

	if (!opts)
		return false;

	if (opts->checkout_strategy == GIT_CHECKOUT_NONE)
		return false;

	return !git_repository_head_unborn(repo);
}

static int checkout_branch(git_repository *repo, git_remote *remote, const git_checkout_options *co_opts, const char *branch, const char *reflog_message)
{
	int error;

	if (branch)
		error = update_head_to_branch(repo, remote, branch, reflog_message);
	/* Point HEAD to the same ref as the remote's head */
	else
		error = update_head_to_remote(repo, remote, reflog_message);

	if (!error && should_checkout(repo, git_repository_is_bare(repo), co_opts))
		error = git_checkout_head(repo, co_opts);

	return error;
}

static int clone_into(git_repository *repo, git_remote *_remote, const git_fetch_options *opts, const git_checkout_options *co_opts, const char *branch)
{
	int error;
	git_str reflog_message = GIT_STR_INIT;
	git_fetch_options fetch_opts;
	git_remote *remote;

	GIT_ASSERT_ARG(repo);
	GIT_ASSERT_ARG(_remote);

	if (!git_repository_is_empty(repo)) {
		git_error_set(GIT_ERROR_INVALID, "the repository is not empty");
		return -1;
	}

	if ((error = git_remote_dup(&remote, _remote)) < 0)
		return error;

	memcpy(&fetch_opts, opts, sizeof(git_fetch_options));
	fetch_opts.update_fetchhead = 0;
	fetch_opts.download_tags = GIT_REMOTE_DOWNLOAD_TAGS_ALL;
	git_str_printf(&reflog_message, "clone: from %s", git_remote_url(remote));

	if ((error = git_remote_fetch(remote, NULL, &fetch_opts, git_str_cstr(&reflog_message))) != 0)
		goto cleanup;

	error = checkout_branch(repo, remote, co_opts, branch, git_str_cstr(&reflog_message));

cleanup:
	git_remote_free(remote);
	git_str_dispose(&reflog_message);

	return error;
}

int git_clone__should_clone_local(const char *url_or_path, git_clone_local_t local)
{
	git_str fromurl = GIT_STR_INIT;
	const char *path = url_or_path;
	bool is_url, is_local;

	if (local == GIT_CLONE_NO_LOCAL)
		return 0;

	if ((is_url = git_fs_path_is_local_file_url(url_or_path)) != 0) {
		if (git_fs_path_fromurl(&fromurl, url_or_path) < 0) {
			is_local = -1;
			goto done;
		}

		path = fromurl.ptr;
	}

	is_local = (!is_url || local != GIT_CLONE_LOCAL_AUTO) &&
		git_fs_path_isdir(path);

done:
	git_str_dispose(&fromurl);
	return is_local;
}

static int git__clone(
	git_repository **out,
	const char *url,
	const char *local_path,
	const git_clone_options *_options,
	int use_existing)
{
	int error = 0;
	git_repository *repo = NULL;
	git_remote *origin;
	git_clone_options options = GIT_CLONE_OPTIONS_INIT;
	uint32_t rmdir_flags = GIT_RMDIR_REMOVE_FILES;
	git_repository_create_cb repository_cb;

	GIT_ASSERT_ARG(out);
	GIT_ASSERT_ARG(url);
	GIT_ASSERT_ARG(local_path);

	if (_options)
		memcpy(&options, _options, sizeof(git_clone_options));

	GIT_ERROR_CHECK_VERSION(&options, GIT_CLONE_OPTIONS_VERSION, "git_clone_options");

	/* Only clone to a new directory or an empty directory */
	if (git_fs_path_exists(local_path) && !use_existing && !git_fs_path_is_empty_dir(local_path)) {
		git_error_set(GIT_ERROR_INVALID,
			"'%s' exists and is not an empty directory", local_path);
		return GIT_EEXISTS;
	}

	/* Only remove the root directory on failure if we create it */
	if (git_fs_path_exists(local_path))
		rmdir_flags |= GIT_RMDIR_SKIP_ROOT;

	if (options.repository_cb)
		repository_cb = options.repository_cb;
	else
		repository_cb = default_repository_create;

	if ((error = repository_cb(&repo, local_path, options.bare, options.repository_cb_payload)) < 0)
		return error;

	if (!(error = create_and_configure_origin(&origin, repo, url, &options))) {
		int clone_local = git_clone__should_clone_local(url, options.local);
		int link = options.local != GIT_CLONE_LOCAL_NO_LINKS;

		if (clone_local == 1)
			error = clone_local_into(
				repo, origin, &options.fetch_opts, &options.checkout_opts,
				options.checkout_branch, link);
		else if (clone_local == 0)
			error = clone_into(
				repo, origin, &options.fetch_opts, &options.checkout_opts,
				options.checkout_branch);
		else
			error = -1;

		git_remote_free(origin);
	}

	if (error != 0) {
		git_error_state last_error = {0};
		git_error_state_capture(&last_error, error);

		git_repository_free(repo);
		repo = NULL;

		(void)git_futils_rmdir_r(local_path, NULL, rmdir_flags);

		git_error_state_restore(&last_error);
	}

	*out = repo;
	return error;
}

int git_clone(
	git_repository **out,
	const char *url,
	const char *local_path,
	const git_clone_options *_options)
{
	return git__clone(out, url, local_path, _options, 0);
}

int git_clone__submodule(
	git_repository **out,
	const char *url,
	const char *local_path,
	const git_clone_options *_options)
{
	return git__clone(out, url, local_path, _options, 1);
}

int git_clone_options_init(git_clone_options *opts, unsigned int version)
{
	GIT_INIT_STRUCTURE_FROM_TEMPLATE(
		opts, version, git_clone_options, GIT_CLONE_OPTIONS_INIT);
	return 0;
}

#ifndef GIT_DEPRECATE_HARD
int git_clone_init_options(git_clone_options *opts, unsigned int version)
{
	return git_clone_options_init(opts, version);
}
#endif

static bool can_link(const char *src, const char *dst, int link)
{
#ifdef GIT_WIN32
	GIT_UNUSED(src);
	GIT_UNUSED(dst);
	GIT_UNUSED(link);
	return false;
#else

	struct stat st_src, st_dst;

	if (!link)
		return false;

	if (p_stat(src, &st_src) < 0)
		return false;

	if (p_stat(dst, &st_dst) < 0)
		return false;

	return st_src.st_dev == st_dst.st_dev;
#endif
}

static int clone_local_into(git_repository *repo, git_remote *remote, const git_fetch_options *fetch_opts, const git_checkout_options *co_opts, const char *branch, int link)
{
	int error, flags;
	git_repository *src;
	git_str src_odb = GIT_STR_INIT, dst_odb = GIT_STR_INIT, src_path = GIT_STR_INIT;
	git_str reflog_message = GIT_STR_INIT;

	GIT_ASSERT_ARG(repo);
	GIT_ASSERT_ARG(remote);

	if (!git_repository_is_empty(repo)) {
		git_error_set(GIT_ERROR_INVALID, "the repository is not empty");
		return -1;
	}

	/*
	 * Let's figure out what path we should use for the source
	 * repo, if it's not rooted, the path should be relative to
	 * the repository's worktree/gitdir.
	 */
	if ((error = git_fs_path_from_url_or_path(&src_path, git_remote_url(remote))) < 0)
		return error;

	/* Copy .git/objects/ from the source to the target */
	if ((error = git_repository_open(&src, git_str_cstr(&src_path))) < 0) {
		git_str_dispose(&src_path);
		return error;
	}

	if (git_repository__item_path(&src_odb, src, GIT_REPOSITORY_ITEM_OBJECTS) < 0 ||
	    git_repository__item_path(&dst_odb, repo, GIT_REPOSITORY_ITEM_OBJECTS) < 0) {
		error = -1;
		goto cleanup;
	}

	flags = 0;
	if (can_link(git_repository_path(src), git_repository_path(repo), link))
		flags |= GIT_CPDIR_LINK_FILES;

	error = git_futils_cp_r(git_str_cstr(&src_odb), git_str_cstr(&dst_odb),
				flags, GIT_OBJECT_DIR_MODE);

	/*
	 * can_link() doesn't catch all variations, so if we hit an
	 * error and did want to link, let's try again without trying
	 * to link.
	 */
	if (error < 0 && link) {
		flags &= ~GIT_CPDIR_LINK_FILES;
		error = git_futils_cp_r(git_str_cstr(&src_odb), git_str_cstr(&dst_odb),
					flags, GIT_OBJECT_DIR_MODE);
	}

	if (error < 0)
		goto cleanup;

	git_str_printf(&reflog_message, "clone: from %s", git_remote_url(remote));

	if ((error = git_remote_fetch(remote, NULL, fetch_opts, git_str_cstr(&reflog_message))) != 0)
		goto cleanup;

	error = checkout_branch(repo, remote, co_opts, branch, git_str_cstr(&reflog_message));

cleanup:
	git_str_dispose(&reflog_message);
	git_str_dispose(&src_path);
	git_str_dispose(&src_odb);
	git_str_dispose(&dst_odb);
	git_repository_free(src);
	return error;
}