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