fix overlapping memcpy in normalize_absolute_path
[git] / builtin-clone.c
1 /*
2  * Builtin "git clone"
3  *
4  * Copyright (c) 2007 Kristian Høgsberg <krh@redhat.com>,
5  *               2008 Daniel Barkalow <barkalow@iabervon.org>
6  * Based on git-commit.sh by Junio C Hamano and Linus Torvalds
7  *
8  * Clone a repository into a different directory that does not yet exist.
9  */
10
11 #include "cache.h"
12 #include "parse-options.h"
13 #include "fetch-pack.h"
14 #include "refs.h"
15 #include "tree.h"
16 #include "tree-walk.h"
17 #include "unpack-trees.h"
18 #include "transport.h"
19 #include "strbuf.h"
20 #include "dir.h"
21 #include "pack-refs.h"
22
23 /*
24  * Overall FIXMEs:
25  *  - respect DB_ENVIRONMENT for .git/objects.
26  *
27  * Implementation notes:
28  *  - dropping use-separate-remote and no-separate-remote compatibility
29  *
30  */
31 static const char * const builtin_clone_usage[] = {
32         "git clone [options] [--] <repo> [<dir>]",
33         NULL
34 };
35
36 static int option_quiet, option_no_checkout, option_bare, option_mirror;
37 static int option_local, option_no_hardlinks, option_shared;
38 static char *option_template, *option_reference, *option_depth;
39 static char *option_origin = NULL;
40 static char *option_upload_pack = "git-upload-pack";
41
42 static struct option builtin_clone_options[] = {
43         OPT__QUIET(&option_quiet),
44         OPT_BOOLEAN('n', "no-checkout", &option_no_checkout,
45                     "don't create a checkout"),
46         OPT_BOOLEAN(0, "bare", &option_bare, "create a bare repository"),
47         OPT_BOOLEAN(0, "naked", &option_bare, "create a bare repository"),
48         OPT_BOOLEAN(0, "mirror", &option_mirror,
49                     "create a mirror repository (implies bare)"),
50         OPT_BOOLEAN('l', "local", &option_local,
51                     "to clone from a local repository"),
52         OPT_BOOLEAN(0, "no-hardlinks", &option_no_hardlinks,
53                     "don't use local hardlinks, always copy"),
54         OPT_BOOLEAN('s', "shared", &option_shared,
55                     "setup as shared repository"),
56         OPT_STRING(0, "template", &option_template, "path",
57                    "path the template repository"),
58         OPT_STRING(0, "reference", &option_reference, "repo",
59                    "reference repository"),
60         OPT_STRING('o', "origin", &option_origin, "branch",
61                    "use <branch> instead of 'origin' to track upstream"),
62         OPT_STRING('u', "upload-pack", &option_upload_pack, "path",
63                    "path to git-upload-pack on the remote"),
64         OPT_STRING(0, "depth", &option_depth, "depth",
65                     "create a shallow clone of that depth"),
66
67         OPT_END()
68 };
69
70 static char *get_repo_path(const char *repo, int *is_bundle)
71 {
72         static char *suffix[] = { "/.git", ".git", "" };
73         static char *bundle_suffix[] = { ".bundle", "" };
74         struct stat st;
75         int i;
76
77         for (i = 0; i < ARRAY_SIZE(suffix); i++) {
78                 const char *path;
79                 path = mkpath("%s%s", repo, suffix[i]);
80                 if (!stat(path, &st) && S_ISDIR(st.st_mode)) {
81                         *is_bundle = 0;
82                         return xstrdup(make_nonrelative_path(path));
83                 }
84         }
85
86         for (i = 0; i < ARRAY_SIZE(bundle_suffix); i++) {
87                 const char *path;
88                 path = mkpath("%s%s", repo, bundle_suffix[i]);
89                 if (!stat(path, &st) && S_ISREG(st.st_mode)) {
90                         *is_bundle = 1;
91                         return xstrdup(make_nonrelative_path(path));
92                 }
93         }
94
95         return NULL;
96 }
97
98 static char *guess_dir_name(const char *repo, int is_bundle, int is_bare)
99 {
100         const char *end = repo + strlen(repo), *start;
101
102         /*
103          * Strip trailing slashes and /.git
104          */
105         while (repo < end && is_dir_sep(end[-1]))
106                 end--;
107         if (end - repo > 5 && is_dir_sep(end[-5]) &&
108             !strncmp(end - 4, ".git", 4)) {
109                 end -= 5;
110                 while (repo < end && is_dir_sep(end[-1]))
111                         end--;
112         }
113
114         /*
115          * Find last component, but be prepared that repo could have
116          * the form  "remote.example.com:foo.git", i.e. no slash
117          * in the directory part.
118          */
119         start = end;
120         while (repo < start && !is_dir_sep(start[-1]) && start[-1] != ':')
121                 start--;
122
123         /*
124          * Strip .{bundle,git}.
125          */
126         if (is_bundle) {
127                 if (end - start > 7 && !strncmp(end - 7, ".bundle", 7))
128                         end -= 7;
129         } else {
130                 if (end - start > 4 && !strncmp(end - 4, ".git", 4))
131                         end -= 4;
132         }
133
134         if (is_bare) {
135                 char *result = xmalloc(end - start + 5);
136                 sprintf(result, "%.*s.git", (int)(end - start), start);
137                 return result;
138         }
139
140         return xstrndup(start, end - start);
141 }
142
143 static int is_directory(const char *path)
144 {
145         struct stat buf;
146
147         return !stat(path, &buf) && S_ISDIR(buf.st_mode);
148 }
149
150 static void strip_trailing_slashes(char *dir)
151 {
152         char *end = dir + strlen(dir);
153
154         while (dir < end - 1 && is_dir_sep(end[-1]))
155                 end--;
156         *end = '\0';
157 }
158
159 static void setup_reference(const char *repo)
160 {
161         const char *ref_git;
162         char *ref_git_copy;
163
164         struct remote *remote;
165         struct transport *transport;
166         const struct ref *extra;
167
168         ref_git = make_absolute_path(option_reference);
169
170         if (is_directory(mkpath("%s/.git/objects", ref_git)))
171                 ref_git = mkpath("%s/.git", ref_git);
172         else if (!is_directory(mkpath("%s/objects", ref_git)))
173                 die("reference repository '%s' is not a local directory.",
174                     option_reference);
175
176         ref_git_copy = xstrdup(ref_git);
177
178         add_to_alternates_file(ref_git_copy);
179
180         remote = remote_get(ref_git_copy);
181         transport = transport_get(remote, ref_git_copy);
182         for (extra = transport_get_remote_refs(transport); extra;
183              extra = extra->next)
184                 add_extra_ref(extra->name, extra->old_sha1, 0);
185
186         transport_disconnect(transport);
187
188         free(ref_git_copy);
189 }
190
191 static void copy_or_link_directory(char *src, char *dest)
192 {
193         struct dirent *de;
194         struct stat buf;
195         int src_len, dest_len;
196         DIR *dir;
197
198         dir = opendir(src);
199         if (!dir)
200                 die("failed to open %s\n", src);
201
202         if (mkdir(dest, 0777)) {
203                 if (errno != EEXIST)
204                         die("failed to create directory %s\n", dest);
205                 else if (stat(dest, &buf))
206                         die("failed to stat %s\n", dest);
207                 else if (!S_ISDIR(buf.st_mode))
208                         die("%s exists and is not a directory\n", dest);
209         }
210
211         src_len = strlen(src);
212         src[src_len] = '/';
213         dest_len = strlen(dest);
214         dest[dest_len] = '/';
215
216         while ((de = readdir(dir)) != NULL) {
217                 strcpy(src + src_len + 1, de->d_name);
218                 strcpy(dest + dest_len + 1, de->d_name);
219                 if (stat(src, &buf)) {
220                         warning ("failed to stat %s\n", src);
221                         continue;
222                 }
223                 if (S_ISDIR(buf.st_mode)) {
224                         if (de->d_name[0] != '.')
225                                 copy_or_link_directory(src, dest);
226                         continue;
227                 }
228
229                 if (unlink(dest) && errno != ENOENT)
230                         die("failed to unlink %s\n", dest);
231                 if (!option_no_hardlinks) {
232                         if (!link(src, dest))
233                                 continue;
234                         if (option_local)
235                                 die("failed to create link %s\n", dest);
236                         option_no_hardlinks = 1;
237                 }
238                 if (copy_file(dest, src, 0666))
239                         die("failed to copy file to %s\n", dest);
240         }
241         closedir(dir);
242 }
243
244 static const struct ref *clone_local(const char *src_repo,
245                                      const char *dest_repo)
246 {
247         const struct ref *ret;
248         char src[PATH_MAX];
249         char dest[PATH_MAX];
250         struct remote *remote;
251         struct transport *transport;
252
253         if (option_shared)
254                 add_to_alternates_file(src_repo);
255         else {
256                 snprintf(src, PATH_MAX, "%s/objects", src_repo);
257                 snprintf(dest, PATH_MAX, "%s/objects", dest_repo);
258                 copy_or_link_directory(src, dest);
259         }
260
261         remote = remote_get(src_repo);
262         transport = transport_get(remote, src_repo);
263         ret = transport_get_remote_refs(transport);
264         transport_disconnect(transport);
265         return ret;
266 }
267
268 static const char *junk_work_tree;
269 static const char *junk_git_dir;
270 pid_t junk_pid;
271
272 static void remove_junk(void)
273 {
274         struct strbuf sb;
275         if (getpid() != junk_pid)
276                 return;
277         strbuf_init(&sb, 0);
278         if (junk_git_dir) {
279                 strbuf_addstr(&sb, junk_git_dir);
280                 remove_dir_recursively(&sb, 0);
281                 strbuf_reset(&sb);
282         }
283         if (junk_work_tree) {
284                 strbuf_addstr(&sb, junk_work_tree);
285                 remove_dir_recursively(&sb, 0);
286                 strbuf_reset(&sb);
287         }
288 }
289
290 static void remove_junk_on_signal(int signo)
291 {
292         remove_junk();
293         signal(SIGINT, SIG_DFL);
294         raise(signo);
295 }
296
297 static const struct ref *locate_head(const struct ref *refs,
298                                      const struct ref *mapped_refs,
299                                      const struct ref **remote_head_p)
300 {
301         const struct ref *remote_head = NULL;
302         const struct ref *remote_master = NULL;
303         const struct ref *r;
304         for (r = refs; r; r = r->next)
305                 if (!strcmp(r->name, "HEAD"))
306                         remote_head = r;
307
308         for (r = mapped_refs; r; r = r->next)
309                 if (!strcmp(r->name, "refs/heads/master"))
310                         remote_master = r;
311
312         if (remote_head_p)
313                 *remote_head_p = remote_head;
314
315         /* If there's no HEAD value at all, never mind. */
316         if (!remote_head)
317                 return NULL;
318
319         /* If refs/heads/master could be right, it is. */
320         if (remote_master && !hashcmp(remote_master->old_sha1,
321                                       remote_head->old_sha1))
322                 return remote_master;
323
324         /* Look for another ref that points there */
325         for (r = mapped_refs; r; r = r->next)
326                 if (r != remote_head &&
327                     !hashcmp(r->old_sha1, remote_head->old_sha1))
328                         return r;
329
330         /* Nothing is the same */
331         return NULL;
332 }
333
334 static struct ref *write_remote_refs(const struct ref *refs,
335                 struct refspec *refspec, const char *reflog)
336 {
337         struct ref *local_refs = NULL;
338         struct ref **tail = &local_refs;
339         struct ref *r;
340
341         get_fetch_map(refs, refspec, &tail, 0);
342         if (!option_mirror)
343                 get_fetch_map(refs, tag_refspec, &tail, 0);
344
345         for (r = local_refs; r; r = r->next)
346                 add_extra_ref(r->peer_ref->name, r->old_sha1, 0);
347
348         pack_refs(PACK_REFS_ALL);
349         clear_extra_refs();
350
351         return local_refs;
352 }
353
354 int cmd_clone(int argc, const char **argv, const char *prefix)
355 {
356         int use_local_hardlinks = 1;
357         int use_separate_remote = 1;
358         int is_bundle = 0;
359         struct stat buf;
360         const char *repo_name, *repo, *work_tree, *git_dir;
361         char *path, *dir;
362         const struct ref *refs, *head_points_at, *remote_head, *mapped_refs;
363         char branch_top[256], key[256], value[256];
364         struct strbuf reflog_msg;
365         struct transport *transport = NULL;
366         char *src_ref_prefix = "refs/heads/";
367
368         struct refspec refspec;
369
370         junk_pid = getpid();
371
372         argc = parse_options(argc, argv, builtin_clone_options,
373                              builtin_clone_usage, 0);
374
375         if (argc == 0)
376                 die("You must specify a repository to clone.");
377
378         if (option_no_hardlinks)
379                 use_local_hardlinks = 0;
380
381         if (option_mirror)
382                 option_bare = 1;
383
384         if (option_bare) {
385                 if (option_origin)
386                         die("--bare and --origin %s options are incompatible.",
387                             option_origin);
388                 option_no_checkout = 1;
389                 use_separate_remote = 0;
390         }
391
392         if (!option_origin)
393                 option_origin = "origin";
394
395         repo_name = argv[0];
396
397         path = get_repo_path(repo_name, &is_bundle);
398         if (path)
399                 repo = xstrdup(make_nonrelative_path(repo_name));
400         else if (!strchr(repo_name, ':'))
401                 repo = xstrdup(make_absolute_path(repo_name));
402         else
403                 repo = repo_name;
404
405         if (argc == 2)
406                 dir = xstrdup(argv[1]);
407         else
408                 dir = guess_dir_name(repo_name, is_bundle, option_bare);
409         strip_trailing_slashes(dir);
410
411         if (!stat(dir, &buf))
412                 die("destination directory '%s' already exists.", dir);
413
414         strbuf_init(&reflog_msg, 0);
415         strbuf_addf(&reflog_msg, "clone: from %s", repo);
416
417         if (option_bare)
418                 work_tree = NULL;
419         else {
420                 work_tree = getenv("GIT_WORK_TREE");
421                 if (work_tree && !stat(work_tree, &buf))
422                         die("working tree '%s' already exists.", work_tree);
423         }
424
425         if (option_bare || work_tree)
426                 git_dir = xstrdup(dir);
427         else {
428                 work_tree = dir;
429                 git_dir = xstrdup(mkpath("%s/.git", dir));
430         }
431
432         if (!option_bare) {
433                 junk_work_tree = work_tree;
434                 if (safe_create_leading_directories_const(work_tree) < 0)
435                         die("could not create leading directories of '%s': %s",
436                                         work_tree, strerror(errno));
437                 if (mkdir(work_tree, 0755))
438                         die("could not create work tree dir '%s': %s.",
439                                         work_tree, strerror(errno));
440                 set_git_work_tree(work_tree);
441         }
442         junk_git_dir = git_dir;
443         atexit(remove_junk);
444         signal(SIGINT, remove_junk_on_signal);
445
446         setenv(CONFIG_ENVIRONMENT, xstrdup(mkpath("%s/config", git_dir)), 1);
447
448         if (safe_create_leading_directories_const(git_dir) < 0)
449                 die("could not create leading directories of '%s'", git_dir);
450         set_git_dir(make_absolute_path(git_dir));
451
452         init_db(option_template, option_quiet ? INIT_DB_QUIET : 0);
453
454         /*
455          * At this point, the config exists, so we do not need the
456          * environment variable.  We actually need to unset it, too, to
457          * re-enable parsing of the global configs.
458          */
459         unsetenv(CONFIG_ENVIRONMENT);
460
461         if (option_reference)
462                 setup_reference(git_dir);
463
464         git_config(git_default_config, NULL);
465
466         if (option_bare) {
467                 if (option_mirror)
468                         src_ref_prefix = "refs/";
469                 strcpy(branch_top, src_ref_prefix);
470
471                 git_config_set("core.bare", "true");
472         } else {
473                 snprintf(branch_top, sizeof(branch_top),
474                          "refs/remotes/%s/", option_origin);
475         }
476
477         if (option_mirror || !option_bare) {
478                 /* Configure the remote */
479                 if (option_mirror) {
480                         snprintf(key, sizeof(key),
481                                         "remote.%s.mirror", option_origin);
482                         git_config_set(key, "true");
483                 }
484
485                 snprintf(key, sizeof(key), "remote.%s.url", option_origin);
486                 git_config_set(key, repo);
487
488                 snprintf(key, sizeof(key), "remote.%s.fetch", option_origin);
489                 snprintf(value, sizeof(value),
490                                 "+%s*:%s*", src_ref_prefix, branch_top);
491                 git_config_set_multivar(key, value, "^$", 0);
492         }
493
494         refspec.force = 0;
495         refspec.pattern = 1;
496         refspec.src = src_ref_prefix;
497         refspec.dst = branch_top;
498
499         if (path && !is_bundle)
500                 refs = clone_local(path, git_dir);
501         else {
502                 struct remote *remote = remote_get(argv[0]);
503                 transport = transport_get(remote, remote->url[0]);
504
505                 if (!transport->get_refs_list || !transport->fetch)
506                         die("Don't know how to clone %s", transport->url);
507
508                 transport_set_option(transport, TRANS_OPT_KEEP, "yes");
509
510                 if (option_depth)
511                         transport_set_option(transport, TRANS_OPT_DEPTH,
512                                              option_depth);
513
514                 if (option_quiet)
515                         transport->verbose = -1;
516
517                 if (option_upload_pack)
518                         transport_set_option(transport, TRANS_OPT_UPLOADPACK,
519                                              option_upload_pack);
520
521                 refs = transport_get_remote_refs(transport);
522                 transport_fetch_refs(transport, refs);
523         }
524
525         clear_extra_refs();
526
527         mapped_refs = write_remote_refs(refs, &refspec, reflog_msg.buf);
528
529         head_points_at = locate_head(refs, mapped_refs, &remote_head);
530
531         if (head_points_at) {
532                 /* Local default branch link */
533                 create_symref("HEAD", head_points_at->name, NULL);
534
535                 if (!option_bare) {
536                         struct strbuf head_ref;
537                         const char *head = head_points_at->name;
538
539                         if (!prefixcmp(head, "refs/heads/"))
540                                 head += 11;
541
542                         /* Set up the initial local branch */
543
544                         /* Local branch initial value */
545                         update_ref(reflog_msg.buf, "HEAD",
546                                    head_points_at->old_sha1,
547                                    NULL, 0, DIE_ON_ERR);
548
549                         strbuf_init(&head_ref, 0);
550                         strbuf_addstr(&head_ref, branch_top);
551                         strbuf_addstr(&head_ref, "HEAD");
552
553                         /* Remote branch link */
554                         create_symref(head_ref.buf,
555                                       head_points_at->peer_ref->name,
556                                       reflog_msg.buf);
557
558                         snprintf(key, sizeof(key), "branch.%s.remote", head);
559                         git_config_set(key, option_origin);
560                         snprintf(key, sizeof(key), "branch.%s.merge", head);
561                         git_config_set(key, head_points_at->name);
562                 }
563         } else if (remote_head) {
564                 /* Source had detached HEAD pointing somewhere. */
565                 if (!option_bare)
566                         update_ref(reflog_msg.buf, "HEAD",
567                                    remote_head->old_sha1,
568                                    NULL, REF_NODEREF, DIE_ON_ERR);
569         } else {
570                 /* Nothing to checkout out */
571                 if (!option_no_checkout)
572                         warning("remote HEAD refers to nonexistent ref, "
573                                 "unable to checkout.\n");
574                 option_no_checkout = 1;
575         }
576
577         if (transport)
578                 transport_unlock_pack(transport);
579
580         if (!option_no_checkout) {
581                 struct lock_file *lock_file = xcalloc(1, sizeof(struct lock_file));
582                 struct unpack_trees_options opts;
583                 struct tree *tree;
584                 struct tree_desc t;
585                 int fd;
586
587                 /* We need to be in the new work tree for the checkout */
588                 setup_work_tree();
589
590                 fd = hold_locked_index(lock_file, 1);
591
592                 memset(&opts, 0, sizeof opts);
593                 opts.update = 1;
594                 opts.merge = 1;
595                 opts.fn = oneway_merge;
596                 opts.verbose_update = !option_quiet;
597                 opts.src_index = &the_index;
598                 opts.dst_index = &the_index;
599
600                 tree = parse_tree_indirect(remote_head->old_sha1);
601                 parse_tree(tree);
602                 init_tree_desc(&t, tree->buffer, tree->size);
603                 unpack_trees(1, &t, &opts);
604
605                 if (write_cache(fd, active_cache, active_nr) ||
606                     commit_locked_index(lock_file))
607                         die("unable to write new index file");
608         }
609
610         strbuf_release(&reflog_msg);
611         junk_pid = 0;
612         return 0;
613 }