Imported Upstream version 2.5.1
[platform/upstream/git.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 "builtin.h"
12 #include "lockfile.h"
13 #include "parse-options.h"
14 #include "fetch-pack.h"
15 #include "refs.h"
16 #include "tree.h"
17 #include "tree-walk.h"
18 #include "unpack-trees.h"
19 #include "transport.h"
20 #include "strbuf.h"
21 #include "dir.h"
22 #include "sigchain.h"
23 #include "branch.h"
24 #include "remote.h"
25 #include "run-command.h"
26 #include "connected.h"
27
28 /*
29  * Overall FIXMEs:
30  *  - respect DB_ENVIRONMENT for .git/objects.
31  *
32  * Implementation notes:
33  *  - dropping use-separate-remote and no-separate-remote compatibility
34  *
35  */
36 static const char * const builtin_clone_usage[] = {
37         N_("git clone [<options>] [--] <repo> [<dir>]"),
38         NULL
39 };
40
41 static int option_no_checkout, option_bare, option_mirror, option_single_branch = -1;
42 static int option_local = -1, option_no_hardlinks, option_shared, option_recursive;
43 static char *option_template, *option_depth;
44 static char *option_origin = NULL;
45 static char *option_branch = NULL;
46 static const char *real_git_dir;
47 static char *option_upload_pack = "git-upload-pack";
48 static int option_verbosity;
49 static int option_progress = -1;
50 static struct string_list option_config;
51 static struct string_list option_reference;
52 static int option_dissociate;
53
54 static struct option builtin_clone_options[] = {
55         OPT__VERBOSITY(&option_verbosity),
56         OPT_BOOL(0, "progress", &option_progress,
57                  N_("force progress reporting")),
58         OPT_BOOL('n', "no-checkout", &option_no_checkout,
59                  N_("don't create a checkout")),
60         OPT_BOOL(0, "bare", &option_bare, N_("create a bare repository")),
61         OPT_HIDDEN_BOOL(0, "naked", &option_bare,
62                         N_("create a bare repository")),
63         OPT_BOOL(0, "mirror", &option_mirror,
64                  N_("create a mirror repository (implies bare)")),
65         OPT_BOOL('l', "local", &option_local,
66                 N_("to clone from a local repository")),
67         OPT_BOOL(0, "no-hardlinks", &option_no_hardlinks,
68                     N_("don't use local hardlinks, always copy")),
69         OPT_BOOL('s', "shared", &option_shared,
70                     N_("setup as shared repository")),
71         OPT_BOOL(0, "recursive", &option_recursive,
72                     N_("initialize submodules in the clone")),
73         OPT_BOOL(0, "recurse-submodules", &option_recursive,
74                     N_("initialize submodules in the clone")),
75         OPT_STRING(0, "template", &option_template, N_("template-directory"),
76                    N_("directory from which templates will be used")),
77         OPT_STRING_LIST(0, "reference", &option_reference, N_("repo"),
78                         N_("reference repository")),
79         OPT_BOOL(0, "dissociate", &option_dissociate,
80                  N_("use --reference only while cloning")),
81         OPT_STRING('o', "origin", &option_origin, N_("name"),
82                    N_("use <name> instead of 'origin' to track upstream")),
83         OPT_STRING('b', "branch", &option_branch, N_("branch"),
84                    N_("checkout <branch> instead of the remote's HEAD")),
85         OPT_STRING('u', "upload-pack", &option_upload_pack, N_("path"),
86                    N_("path to git-upload-pack on the remote")),
87         OPT_STRING(0, "depth", &option_depth, N_("depth"),
88                     N_("create a shallow clone of that depth")),
89         OPT_BOOL(0, "single-branch", &option_single_branch,
90                     N_("clone only one branch, HEAD or --branch")),
91         OPT_STRING(0, "separate-git-dir", &real_git_dir, N_("gitdir"),
92                    N_("separate git dir from working tree")),
93         OPT_STRING_LIST('c', "config", &option_config, N_("key=value"),
94                         N_("set config inside the new repository")),
95         OPT_END()
96 };
97
98 static const char *argv_submodule[] = {
99         "submodule", "update", "--init", "--recursive", NULL
100 };
101
102 static char *get_repo_path(const char *repo, int *is_bundle)
103 {
104         static char *suffix[] = { "/.git", "", ".git/.git", ".git" };
105         static char *bundle_suffix[] = { ".bundle", "" };
106         struct stat st;
107         int i;
108
109         for (i = 0; i < ARRAY_SIZE(suffix); i++) {
110                 const char *path;
111                 path = mkpath("%s%s", repo, suffix[i]);
112                 if (stat(path, &st))
113                         continue;
114                 if (S_ISDIR(st.st_mode) && is_git_directory(path)) {
115                         *is_bundle = 0;
116                         return xstrdup(absolute_path(path));
117                 } else if (S_ISREG(st.st_mode) && st.st_size > 8) {
118                         /* Is it a "gitfile"? */
119                         char signature[8];
120                         int len, fd = open(path, O_RDONLY);
121                         if (fd < 0)
122                                 continue;
123                         len = read_in_full(fd, signature, 8);
124                         close(fd);
125                         if (len != 8 || strncmp(signature, "gitdir: ", 8))
126                                 continue;
127                         path = read_gitfile(path);
128                         if (path) {
129                                 *is_bundle = 0;
130                                 return xstrdup(absolute_path(path));
131                         }
132                 }
133         }
134
135         for (i = 0; i < ARRAY_SIZE(bundle_suffix); i++) {
136                 const char *path;
137                 path = mkpath("%s%s", repo, bundle_suffix[i]);
138                 if (!stat(path, &st) && S_ISREG(st.st_mode)) {
139                         *is_bundle = 1;
140                         return xstrdup(absolute_path(path));
141                 }
142         }
143
144         return NULL;
145 }
146
147 static char *guess_dir_name(const char *repo, int is_bundle, int is_bare)
148 {
149         const char *end = repo + strlen(repo), *start;
150         size_t len;
151         char *dir;
152
153         /*
154          * Strip trailing spaces, slashes and /.git
155          */
156         while (repo < end && (is_dir_sep(end[-1]) || isspace(end[-1])))
157                 end--;
158         if (end - repo > 5 && is_dir_sep(end[-5]) &&
159             !strncmp(end - 4, ".git", 4)) {
160                 end -= 5;
161                 while (repo < end && is_dir_sep(end[-1]))
162                         end--;
163         }
164
165         /*
166          * Find last component, but be prepared that repo could have
167          * the form  "remote.example.com:foo.git", i.e. no slash
168          * in the directory part.
169          */
170         start = end;
171         while (repo < start && !is_dir_sep(start[-1]) && start[-1] != ':')
172                 start--;
173
174         /*
175          * Strip .{bundle,git}.
176          */
177         len = end - start;
178         strip_suffix_mem(start, &len, is_bundle ? ".bundle" : ".git");
179
180         if (is_bare)
181                 dir = xstrfmt("%.*s.git", (int)len, start);
182         else
183                 dir = xstrndup(start, len);
184         /*
185          * Replace sequences of 'control' characters and whitespace
186          * with one ascii space, remove leading and trailing spaces.
187          */
188         if (*dir) {
189                 char *out = dir;
190                 int prev_space = 1 /* strip leading whitespace */;
191                 for (end = dir; *end; ++end) {
192                         char ch = *end;
193                         if ((unsigned char)ch < '\x20')
194                                 ch = '\x20';
195                         if (isspace(ch)) {
196                                 if (prev_space)
197                                         continue;
198                                 prev_space = 1;
199                         } else
200                                 prev_space = 0;
201                         *out++ = ch;
202                 }
203                 *out = '\0';
204                 if (out > dir && prev_space)
205                         out[-1] = '\0';
206         }
207         return dir;
208 }
209
210 static void strip_trailing_slashes(char *dir)
211 {
212         char *end = dir + strlen(dir);
213
214         while (dir < end - 1 && is_dir_sep(end[-1]))
215                 end--;
216         *end = '\0';
217 }
218
219 static int add_one_reference(struct string_list_item *item, void *cb_data)
220 {
221         char *ref_git;
222         const char *repo;
223         struct strbuf alternate = STRBUF_INIT;
224
225         /* Beware: read_gitfile(), real_path() and mkpath() return static buffer */
226         ref_git = xstrdup(real_path(item->string));
227
228         repo = read_gitfile(ref_git);
229         if (!repo)
230                 repo = read_gitfile(mkpath("%s/.git", ref_git));
231         if (repo) {
232                 free(ref_git);
233                 ref_git = xstrdup(repo);
234         }
235
236         if (!repo && is_directory(mkpath("%s/.git/objects", ref_git))) {
237                 char *ref_git_git = mkpathdup("%s/.git", ref_git);
238                 free(ref_git);
239                 ref_git = ref_git_git;
240         } else if (!is_directory(mkpath("%s/objects", ref_git)))
241                 die(_("reference repository '%s' is not a local repository."),
242                     item->string);
243
244         if (!access(mkpath("%s/shallow", ref_git), F_OK))
245                 die(_("reference repository '%s' is shallow"), item->string);
246
247         if (!access(mkpath("%s/info/grafts", ref_git), F_OK))
248                 die(_("reference repository '%s' is grafted"), item->string);
249
250         strbuf_addf(&alternate, "%s/objects", ref_git);
251         add_to_alternates_file(alternate.buf);
252         strbuf_release(&alternate);
253         free(ref_git);
254         return 0;
255 }
256
257 static void setup_reference(void)
258 {
259         for_each_string_list(&option_reference, add_one_reference, NULL);
260 }
261
262 static void copy_alternates(struct strbuf *src, struct strbuf *dst,
263                             const char *src_repo)
264 {
265         /*
266          * Read from the source objects/info/alternates file
267          * and copy the entries to corresponding file in the
268          * destination repository with add_to_alternates_file().
269          * Both src and dst have "$path/objects/info/alternates".
270          *
271          * Instead of copying bit-for-bit from the original,
272          * we need to append to existing one so that the already
273          * created entry via "clone -s" is not lost, and also
274          * to turn entries with paths relative to the original
275          * absolute, so that they can be used in the new repository.
276          */
277         FILE *in = fopen(src->buf, "r");
278         struct strbuf line = STRBUF_INIT;
279
280         while (strbuf_getline(&line, in, '\n') != EOF) {
281                 char *abs_path;
282                 if (!line.len || line.buf[0] == '#')
283                         continue;
284                 if (is_absolute_path(line.buf)) {
285                         add_to_alternates_file(line.buf);
286                         continue;
287                 }
288                 abs_path = mkpathdup("%s/objects/%s", src_repo, line.buf);
289                 normalize_path_copy(abs_path, abs_path);
290                 add_to_alternates_file(abs_path);
291                 free(abs_path);
292         }
293         strbuf_release(&line);
294         fclose(in);
295 }
296
297 static void copy_or_link_directory(struct strbuf *src, struct strbuf *dest,
298                                    const char *src_repo, int src_baselen)
299 {
300         struct dirent *de;
301         struct stat buf;
302         int src_len, dest_len;
303         DIR *dir;
304
305         dir = opendir(src->buf);
306         if (!dir)
307                 die_errno(_("failed to open '%s'"), src->buf);
308
309         if (mkdir(dest->buf, 0777)) {
310                 if (errno != EEXIST)
311                         die_errno(_("failed to create directory '%s'"), dest->buf);
312                 else if (stat(dest->buf, &buf))
313                         die_errno(_("failed to stat '%s'"), dest->buf);
314                 else if (!S_ISDIR(buf.st_mode))
315                         die(_("%s exists and is not a directory"), dest->buf);
316         }
317
318         strbuf_addch(src, '/');
319         src_len = src->len;
320         strbuf_addch(dest, '/');
321         dest_len = dest->len;
322
323         while ((de = readdir(dir)) != NULL) {
324                 strbuf_setlen(src, src_len);
325                 strbuf_addstr(src, de->d_name);
326                 strbuf_setlen(dest, dest_len);
327                 strbuf_addstr(dest, de->d_name);
328                 if (stat(src->buf, &buf)) {
329                         warning (_("failed to stat %s\n"), src->buf);
330                         continue;
331                 }
332                 if (S_ISDIR(buf.st_mode)) {
333                         if (de->d_name[0] != '.')
334                                 copy_or_link_directory(src, dest,
335                                                        src_repo, src_baselen);
336                         continue;
337                 }
338
339                 /* Files that cannot be copied bit-for-bit... */
340                 if (!strcmp(src->buf + src_baselen, "/info/alternates")) {
341                         copy_alternates(src, dest, src_repo);
342                         continue;
343                 }
344
345                 if (unlink(dest->buf) && errno != ENOENT)
346                         die_errno(_("failed to unlink '%s'"), dest->buf);
347                 if (!option_no_hardlinks) {
348                         if (!link(src->buf, dest->buf))
349                                 continue;
350                         if (option_local > 0)
351                                 die_errno(_("failed to create link '%s'"), dest->buf);
352                         option_no_hardlinks = 1;
353                 }
354                 if (copy_file_with_time(dest->buf, src->buf, 0666))
355                         die_errno(_("failed to copy file to '%s'"), dest->buf);
356         }
357         closedir(dir);
358 }
359
360 static void clone_local(const char *src_repo, const char *dest_repo)
361 {
362         if (option_shared) {
363                 struct strbuf alt = STRBUF_INIT;
364                 strbuf_addf(&alt, "%s/objects", src_repo);
365                 add_to_alternates_file(alt.buf);
366                 strbuf_release(&alt);
367         } else {
368                 struct strbuf src = STRBUF_INIT;
369                 struct strbuf dest = STRBUF_INIT;
370                 strbuf_addf(&src, "%s/objects", src_repo);
371                 strbuf_addf(&dest, "%s/objects", dest_repo);
372                 copy_or_link_directory(&src, &dest, src_repo, src.len);
373                 strbuf_release(&src);
374                 strbuf_release(&dest);
375         }
376
377         if (0 <= option_verbosity)
378                 fprintf(stderr, _("done.\n"));
379 }
380
381 static const char *junk_work_tree;
382 static const char *junk_git_dir;
383 static enum {
384         JUNK_LEAVE_NONE,
385         JUNK_LEAVE_REPO,
386         JUNK_LEAVE_ALL
387 } junk_mode = JUNK_LEAVE_NONE;
388
389 static const char junk_leave_repo_msg[] =
390 N_("Clone succeeded, but checkout failed.\n"
391    "You can inspect what was checked out with 'git status'\n"
392    "and retry the checkout with 'git checkout -f HEAD'\n");
393
394 static void remove_junk(void)
395 {
396         struct strbuf sb = STRBUF_INIT;
397
398         switch (junk_mode) {
399         case JUNK_LEAVE_REPO:
400                 warning("%s", _(junk_leave_repo_msg));
401                 /* fall-through */
402         case JUNK_LEAVE_ALL:
403                 return;
404         default:
405                 /* proceed to removal */
406                 break;
407         }
408
409         if (junk_git_dir) {
410                 strbuf_addstr(&sb, junk_git_dir);
411                 remove_dir_recursively(&sb, 0);
412                 strbuf_reset(&sb);
413         }
414         if (junk_work_tree) {
415                 strbuf_addstr(&sb, junk_work_tree);
416                 remove_dir_recursively(&sb, 0);
417                 strbuf_reset(&sb);
418         }
419 }
420
421 static void remove_junk_on_signal(int signo)
422 {
423         remove_junk();
424         sigchain_pop(signo);
425         raise(signo);
426 }
427
428 static struct ref *find_remote_branch(const struct ref *refs, const char *branch)
429 {
430         struct ref *ref;
431         struct strbuf head = STRBUF_INIT;
432         strbuf_addstr(&head, "refs/heads/");
433         strbuf_addstr(&head, branch);
434         ref = find_ref_by_name(refs, head.buf);
435         strbuf_release(&head);
436
437         if (ref)
438                 return ref;
439
440         strbuf_addstr(&head, "refs/tags/");
441         strbuf_addstr(&head, branch);
442         ref = find_ref_by_name(refs, head.buf);
443         strbuf_release(&head);
444
445         return ref;
446 }
447
448 static struct ref *wanted_peer_refs(const struct ref *refs,
449                 struct refspec *refspec)
450 {
451         struct ref *head = copy_ref(find_ref_by_name(refs, "HEAD"));
452         struct ref *local_refs = head;
453         struct ref **tail = head ? &head->next : &local_refs;
454
455         if (option_single_branch) {
456                 struct ref *remote_head = NULL;
457
458                 if (!option_branch)
459                         remote_head = guess_remote_head(head, refs, 0);
460                 else {
461                         local_refs = NULL;
462                         tail = &local_refs;
463                         remote_head = copy_ref(find_remote_branch(refs, option_branch));
464                 }
465
466                 if (!remote_head && option_branch)
467                         warning(_("Could not find remote branch %s to clone."),
468                                 option_branch);
469                 else {
470                         get_fetch_map(remote_head, refspec, &tail, 0);
471
472                         /* if --branch=tag, pull the requested tag explicitly */
473                         get_fetch_map(remote_head, tag_refspec, &tail, 0);
474                 }
475         } else
476                 get_fetch_map(refs, refspec, &tail, 0);
477
478         if (!option_mirror && !option_single_branch)
479                 get_fetch_map(refs, tag_refspec, &tail, 0);
480
481         return local_refs;
482 }
483
484 static void write_remote_refs(const struct ref *local_refs)
485 {
486         const struct ref *r;
487
488         lock_packed_refs(LOCK_DIE_ON_ERROR);
489
490         for (r = local_refs; r; r = r->next) {
491                 if (!r->peer_ref)
492                         continue;
493                 add_packed_ref(r->peer_ref->name, r->old_sha1);
494         }
495
496         if (commit_packed_refs())
497                 die_errno("unable to overwrite old ref-pack file");
498 }
499
500 static void write_followtags(const struct ref *refs, const char *msg)
501 {
502         const struct ref *ref;
503         for (ref = refs; ref; ref = ref->next) {
504                 if (!starts_with(ref->name, "refs/tags/"))
505                         continue;
506                 if (ends_with(ref->name, "^{}"))
507                         continue;
508                 if (!has_sha1_file(ref->old_sha1))
509                         continue;
510                 update_ref(msg, ref->name, ref->old_sha1,
511                            NULL, 0, UPDATE_REFS_DIE_ON_ERR);
512         }
513 }
514
515 static int iterate_ref_map(void *cb_data, unsigned char sha1[20])
516 {
517         struct ref **rm = cb_data;
518         struct ref *ref = *rm;
519
520         /*
521          * Skip anything missing a peer_ref, which we are not
522          * actually going to write a ref for.
523          */
524         while (ref && !ref->peer_ref)
525                 ref = ref->next;
526         /* Returning -1 notes "end of list" to the caller. */
527         if (!ref)
528                 return -1;
529
530         hashcpy(sha1, ref->old_sha1);
531         *rm = ref->next;
532         return 0;
533 }
534
535 static void update_remote_refs(const struct ref *refs,
536                                const struct ref *mapped_refs,
537                                const struct ref *remote_head_points_at,
538                                const char *branch_top,
539                                const char *msg,
540                                struct transport *transport,
541                                int check_connectivity)
542 {
543         const struct ref *rm = mapped_refs;
544
545         if (check_connectivity) {
546                 if (transport->progress)
547                         fprintf(stderr, _("Checking connectivity... "));
548                 if (check_everything_connected_with_transport(iterate_ref_map,
549                                                               0, &rm, transport))
550                         die(_("remote did not send all necessary objects"));
551                 if (transport->progress)
552                         fprintf(stderr, _("done.\n"));
553         }
554
555         if (refs) {
556                 write_remote_refs(mapped_refs);
557                 if (option_single_branch)
558                         write_followtags(refs, msg);
559         }
560
561         if (remote_head_points_at && !option_bare) {
562                 struct strbuf head_ref = STRBUF_INIT;
563                 strbuf_addstr(&head_ref, branch_top);
564                 strbuf_addstr(&head_ref, "HEAD");
565                 create_symref(head_ref.buf,
566                               remote_head_points_at->peer_ref->name,
567                               msg);
568         }
569 }
570
571 static void update_head(const struct ref *our, const struct ref *remote,
572                         const char *msg)
573 {
574         const char *head;
575         if (our && skip_prefix(our->name, "refs/heads/", &head)) {
576                 /* Local default branch link */
577                 create_symref("HEAD", our->name, NULL);
578                 if (!option_bare) {
579                         update_ref(msg, "HEAD", our->old_sha1, NULL, 0,
580                                    UPDATE_REFS_DIE_ON_ERR);
581                         install_branch_config(0, head, option_origin, our->name);
582                 }
583         } else if (our) {
584                 struct commit *c = lookup_commit_reference(our->old_sha1);
585                 /* --branch specifies a non-branch (i.e. tags), detach HEAD */
586                 update_ref(msg, "HEAD", c->object.sha1,
587                            NULL, REF_NODEREF, UPDATE_REFS_DIE_ON_ERR);
588         } else if (remote) {
589                 /*
590                  * We know remote HEAD points to a non-branch, or
591                  * HEAD points to a branch but we don't know which one.
592                  * Detach HEAD in all these cases.
593                  */
594                 update_ref(msg, "HEAD", remote->old_sha1,
595                            NULL, REF_NODEREF, UPDATE_REFS_DIE_ON_ERR);
596         }
597 }
598
599 static int checkout(void)
600 {
601         unsigned char sha1[20];
602         char *head;
603         struct lock_file *lock_file;
604         struct unpack_trees_options opts;
605         struct tree *tree;
606         struct tree_desc t;
607         int err = 0;
608
609         if (option_no_checkout)
610                 return 0;
611
612         head = resolve_refdup("HEAD", RESOLVE_REF_READING, sha1, NULL);
613         if (!head) {
614                 warning(_("remote HEAD refers to nonexistent ref, "
615                           "unable to checkout.\n"));
616                 return 0;
617         }
618         if (!strcmp(head, "HEAD")) {
619                 if (advice_detached_head)
620                         detach_advice(sha1_to_hex(sha1));
621         } else {
622                 if (!starts_with(head, "refs/heads/"))
623                         die(_("HEAD not found below refs/heads!"));
624         }
625         free(head);
626
627         /* We need to be in the new work tree for the checkout */
628         setup_work_tree();
629
630         lock_file = xcalloc(1, sizeof(struct lock_file));
631         hold_locked_index(lock_file, 1);
632
633         memset(&opts, 0, sizeof opts);
634         opts.update = 1;
635         opts.merge = 1;
636         opts.fn = oneway_merge;
637         opts.verbose_update = (option_verbosity >= 0);
638         opts.src_index = &the_index;
639         opts.dst_index = &the_index;
640
641         tree = parse_tree_indirect(sha1);
642         parse_tree(tree);
643         init_tree_desc(&t, tree->buffer, tree->size);
644         if (unpack_trees(1, &t, &opts) < 0)
645                 die(_("unable to checkout working tree"));
646
647         if (write_locked_index(&the_index, lock_file, COMMIT_LOCK))
648                 die(_("unable to write new index file"));
649
650         err |= run_hook_le(NULL, "post-checkout", sha1_to_hex(null_sha1),
651                            sha1_to_hex(sha1), "1", NULL);
652
653         if (!err && option_recursive)
654                 err = run_command_v_opt(argv_submodule, RUN_GIT_CMD);
655
656         return err;
657 }
658
659 static int write_one_config(const char *key, const char *value, void *data)
660 {
661         return git_config_set_multivar(key, value ? value : "true", "^$", 0);
662 }
663
664 static void write_config(struct string_list *config)
665 {
666         int i;
667
668         for (i = 0; i < config->nr; i++) {
669                 if (git_config_parse_parameter(config->items[i].string,
670                                                write_one_config, NULL) < 0)
671                         die("unable to write parameters to config file");
672         }
673 }
674
675 static void write_refspec_config(const char *src_ref_prefix,
676                 const struct ref *our_head_points_at,
677                 const struct ref *remote_head_points_at,
678                 struct strbuf *branch_top)
679 {
680         struct strbuf key = STRBUF_INIT;
681         struct strbuf value = STRBUF_INIT;
682
683         if (option_mirror || !option_bare) {
684                 if (option_single_branch && !option_mirror) {
685                         if (option_branch) {
686                                 if (starts_with(our_head_points_at->name, "refs/tags/"))
687                                         strbuf_addf(&value, "+%s:%s", our_head_points_at->name,
688                                                 our_head_points_at->name);
689                                 else
690                                         strbuf_addf(&value, "+%s:%s%s", our_head_points_at->name,
691                                                 branch_top->buf, option_branch);
692                         } else if (remote_head_points_at) {
693                                 const char *head = remote_head_points_at->name;
694                                 if (!skip_prefix(head, "refs/heads/", &head))
695                                         die("BUG: remote HEAD points at non-head?");
696
697                                 strbuf_addf(&value, "+%s:%s%s", remote_head_points_at->name,
698                                                 branch_top->buf, head);
699                         }
700                         /*
701                          * otherwise, the next "git fetch" will
702                          * simply fetch from HEAD without updating
703                          * any remote-tracking branch, which is what
704                          * we want.
705                          */
706                 } else {
707                         strbuf_addf(&value, "+%s*:%s*", src_ref_prefix, branch_top->buf);
708                 }
709                 /* Configure the remote */
710                 if (value.len) {
711                         strbuf_addf(&key, "remote.%s.fetch", option_origin);
712                         git_config_set_multivar(key.buf, value.buf, "^$", 0);
713                         strbuf_reset(&key);
714
715                         if (option_mirror) {
716                                 strbuf_addf(&key, "remote.%s.mirror", option_origin);
717                                 git_config_set(key.buf, "true");
718                                 strbuf_reset(&key);
719                         }
720                 }
721         }
722
723         strbuf_release(&key);
724         strbuf_release(&value);
725 }
726
727 static void dissociate_from_references(void)
728 {
729         static const char* argv[] = { "repack", "-a", "-d", NULL };
730
731         if (run_command_v_opt(argv, RUN_GIT_CMD|RUN_COMMAND_NO_STDIN))
732                 die(_("cannot repack to clean up"));
733         if (unlink(git_path("objects/info/alternates")) && errno != ENOENT)
734                 die_errno(_("cannot unlink temporary alternates file"));
735 }
736
737 int cmd_clone(int argc, const char **argv, const char *prefix)
738 {
739         int is_bundle = 0, is_local;
740         struct stat buf;
741         const char *repo_name, *repo, *work_tree, *git_dir;
742         char *path, *dir;
743         int dest_exists;
744         const struct ref *refs, *remote_head;
745         const struct ref *remote_head_points_at;
746         const struct ref *our_head_points_at;
747         struct ref *mapped_refs;
748         const struct ref *ref;
749         struct strbuf key = STRBUF_INIT, value = STRBUF_INIT;
750         struct strbuf branch_top = STRBUF_INIT, reflog_msg = STRBUF_INIT;
751         struct transport *transport = NULL;
752         const char *src_ref_prefix = "refs/heads/";
753         struct remote *remote;
754         int err = 0, complete_refs_before_fetch = 1;
755
756         struct refspec *refspec;
757         const char *fetch_pattern;
758
759         packet_trace_identity("clone");
760         argc = parse_options(argc, argv, prefix, builtin_clone_options,
761                              builtin_clone_usage, 0);
762
763         if (argc > 2)
764                 usage_msg_opt(_("Too many arguments."),
765                         builtin_clone_usage, builtin_clone_options);
766
767         if (argc == 0)
768                 usage_msg_opt(_("You must specify a repository to clone."),
769                         builtin_clone_usage, builtin_clone_options);
770
771         if (option_single_branch == -1)
772                 option_single_branch = option_depth ? 1 : 0;
773
774         if (option_mirror)
775                 option_bare = 1;
776
777         if (option_bare) {
778                 if (option_origin)
779                         die(_("--bare and --origin %s options are incompatible."),
780                             option_origin);
781                 if (real_git_dir)
782                         die(_("--bare and --separate-git-dir are incompatible."));
783                 option_no_checkout = 1;
784         }
785
786         if (!option_origin)
787                 option_origin = "origin";
788
789         repo_name = argv[0];
790
791         path = get_repo_path(repo_name, &is_bundle);
792         if (path)
793                 repo = xstrdup(absolute_path(repo_name));
794         else if (!strchr(repo_name, ':'))
795                 die(_("repository '%s' does not exist"), repo_name);
796         else
797                 repo = repo_name;
798
799         /* no need to be strict, transport_set_option() will validate it again */
800         if (option_depth && atoi(option_depth) < 1)
801                 die(_("depth %s is not a positive number"), option_depth);
802
803         if (argc == 2)
804                 dir = xstrdup(argv[1]);
805         else
806                 dir = guess_dir_name(repo_name, is_bundle, option_bare);
807         strip_trailing_slashes(dir);
808
809         dest_exists = !stat(dir, &buf);
810         if (dest_exists && !is_empty_dir(dir))
811                 die(_("destination path '%s' already exists and is not "
812                         "an empty directory."), dir);
813
814         strbuf_addf(&reflog_msg, "clone: from %s", repo);
815
816         if (option_bare)
817                 work_tree = NULL;
818         else {
819                 work_tree = getenv("GIT_WORK_TREE");
820                 if (work_tree && !stat(work_tree, &buf))
821                         die(_("working tree '%s' already exists."), work_tree);
822         }
823
824         if (option_bare || work_tree)
825                 git_dir = xstrdup(dir);
826         else {
827                 work_tree = dir;
828                 git_dir = mkpathdup("%s/.git", dir);
829         }
830
831         atexit(remove_junk);
832         sigchain_push_common(remove_junk_on_signal);
833
834         if (!option_bare) {
835                 if (safe_create_leading_directories_const(work_tree) < 0)
836                         die_errno(_("could not create leading directories of '%s'"),
837                                   work_tree);
838                 if (!dest_exists && mkdir(work_tree, 0777))
839                         die_errno(_("could not create work tree dir '%s'"),
840                                   work_tree);
841                 junk_work_tree = work_tree;
842                 set_git_work_tree(work_tree);
843         }
844
845         junk_git_dir = git_dir;
846         if (safe_create_leading_directories_const(git_dir) < 0)
847                 die(_("could not create leading directories of '%s'"), git_dir);
848
849         set_git_dir_init(git_dir, real_git_dir, 0);
850         if (real_git_dir) {
851                 git_dir = real_git_dir;
852                 junk_git_dir = real_git_dir;
853         }
854
855         if (0 <= option_verbosity) {
856                 if (option_bare)
857                         fprintf(stderr, _("Cloning into bare repository '%s'...\n"), dir);
858                 else
859                         fprintf(stderr, _("Cloning into '%s'...\n"), dir);
860         }
861         init_db(option_template, INIT_DB_QUIET);
862         write_config(&option_config);
863
864         git_config(git_default_config, NULL);
865
866         if (option_bare) {
867                 if (option_mirror)
868                         src_ref_prefix = "refs/";
869                 strbuf_addstr(&branch_top, src_ref_prefix);
870
871                 git_config_set("core.bare", "true");
872         } else {
873                 strbuf_addf(&branch_top, "refs/remotes/%s/", option_origin);
874         }
875
876         strbuf_addf(&value, "+%s*:%s*", src_ref_prefix, branch_top.buf);
877         strbuf_addf(&key, "remote.%s.url", option_origin);
878         git_config_set(key.buf, repo);
879         strbuf_reset(&key);
880
881         if (option_reference.nr)
882                 setup_reference();
883         else if (option_dissociate) {
884                 warning(_("--dissociate given, but there is no --reference"));
885                 option_dissociate = 0;
886         }
887
888         fetch_pattern = value.buf;
889         refspec = parse_fetch_refspec(1, &fetch_pattern);
890
891         strbuf_reset(&value);
892
893         remote = remote_get(option_origin);
894         transport = transport_get(remote, remote->url[0]);
895         transport_set_verbosity(transport, option_verbosity, option_progress);
896
897         path = get_repo_path(remote->url[0], &is_bundle);
898         is_local = option_local != 0 && path && !is_bundle;
899         if (is_local) {
900                 if (option_depth)
901                         warning(_("--depth is ignored in local clones; use file:// instead."));
902                 if (!access(mkpath("%s/shallow", path), F_OK)) {
903                         if (option_local > 0)
904                                 warning(_("source repository is shallow, ignoring --local"));
905                         is_local = 0;
906                 }
907         }
908         if (option_local > 0 && !is_local)
909                 warning(_("--local is ignored"));
910         transport->cloning = 1;
911
912         if (!transport->get_refs_list || (!is_local && !transport->fetch))
913                 die(_("Don't know how to clone %s"), transport->url);
914
915         transport_set_option(transport, TRANS_OPT_KEEP, "yes");
916
917         if (option_depth)
918                 transport_set_option(transport, TRANS_OPT_DEPTH,
919                                      option_depth);
920         if (option_single_branch)
921                 transport_set_option(transport, TRANS_OPT_FOLLOWTAGS, "1");
922
923         if (option_upload_pack)
924                 transport_set_option(transport, TRANS_OPT_UPLOADPACK,
925                                      option_upload_pack);
926
927         if (transport->smart_options && !option_depth)
928                 transport->smart_options->check_self_contained_and_connected = 1;
929
930         refs = transport_get_remote_refs(transport);
931
932         if (refs) {
933                 mapped_refs = wanted_peer_refs(refs, refspec);
934                 /*
935                  * transport_get_remote_refs() may return refs with null sha-1
936                  * in mapped_refs (see struct transport->get_refs_list
937                  * comment). In that case we need fetch it early because
938                  * remote_head code below relies on it.
939                  *
940                  * for normal clones, transport_get_remote_refs() should
941                  * return reliable ref set, we can delay cloning until after
942                  * remote HEAD check.
943                  */
944                 for (ref = refs; ref; ref = ref->next)
945                         if (is_null_sha1(ref->old_sha1)) {
946                                 complete_refs_before_fetch = 0;
947                                 break;
948                         }
949
950                 if (!is_local && !complete_refs_before_fetch)
951                         transport_fetch_refs(transport, mapped_refs);
952
953                 remote_head = find_ref_by_name(refs, "HEAD");
954                 remote_head_points_at =
955                         guess_remote_head(remote_head, mapped_refs, 0);
956
957                 if (option_branch) {
958                         our_head_points_at =
959                                 find_remote_branch(mapped_refs, option_branch);
960
961                         if (!our_head_points_at)
962                                 die(_("Remote branch %s not found in upstream %s"),
963                                     option_branch, option_origin);
964                 }
965                 else
966                         our_head_points_at = remote_head_points_at;
967         }
968         else {
969                 if (option_branch)
970                         die(_("Remote branch %s not found in upstream %s"),
971                                         option_branch, option_origin);
972
973                 warning(_("You appear to have cloned an empty repository."));
974                 mapped_refs = NULL;
975                 our_head_points_at = NULL;
976                 remote_head_points_at = NULL;
977                 remote_head = NULL;
978                 option_no_checkout = 1;
979                 if (!option_bare)
980                         install_branch_config(0, "master", option_origin,
981                                               "refs/heads/master");
982         }
983
984         write_refspec_config(src_ref_prefix, our_head_points_at,
985                         remote_head_points_at, &branch_top);
986
987         if (is_local)
988                 clone_local(path, git_dir);
989         else if (refs && complete_refs_before_fetch)
990                 transport_fetch_refs(transport, mapped_refs);
991
992         update_remote_refs(refs, mapped_refs, remote_head_points_at,
993                            branch_top.buf, reflog_msg.buf, transport, !is_local);
994
995         update_head(our_head_points_at, remote_head, reflog_msg.buf);
996
997         transport_unlock_pack(transport);
998         transport_disconnect(transport);
999
1000         if (option_dissociate)
1001                 dissociate_from_references();
1002
1003         junk_mode = JUNK_LEAVE_REPO;
1004         err = checkout();
1005
1006         strbuf_release(&reflog_msg);
1007         strbuf_release(&branch_top);
1008         strbuf_release(&key);
1009         strbuf_release(&value);
1010         junk_mode = JUNK_LEAVE_ALL;
1011
1012         free(refspec);
1013         return err;
1014 }