wrapper.c: add xpread() similar to xread()
[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 "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 "sigchain.h"
22 #include "branch.h"
23 #include "remote.h"
24 #include "run-command.h"
25 #include "connected.h"
26
27 /*
28  * Overall FIXMEs:
29  *  - respect DB_ENVIRONMENT for .git/objects.
30  *
31  * Implementation notes:
32  *  - dropping use-separate-remote and no-separate-remote compatibility
33  *
34  */
35 static const char * const builtin_clone_usage[] = {
36         N_("git clone [options] [--] <repo> [<dir>]"),
37         NULL
38 };
39
40 static int option_no_checkout, option_bare, option_mirror, option_single_branch = -1;
41 static int option_local = -1, option_no_hardlinks, option_shared, option_recursive;
42 static char *option_template, *option_depth;
43 static char *option_origin = NULL;
44 static char *option_branch = NULL;
45 static const char *real_git_dir;
46 static char *option_upload_pack = "git-upload-pack";
47 static int option_verbosity;
48 static int option_progress = -1;
49 static struct string_list option_config;
50 static struct string_list option_reference;
51
52 static int opt_parse_reference(const struct option *opt, const char *arg, int unset)
53 {
54         struct string_list *option_reference = opt->value;
55         if (!arg)
56                 return -1;
57         string_list_append(option_reference, arg);
58         return 0;
59 }
60
61 static struct option builtin_clone_options[] = {
62         OPT__VERBOSITY(&option_verbosity),
63         OPT_BOOL(0, "progress", &option_progress,
64                  N_("force progress reporting")),
65         OPT_BOOL('n', "no-checkout", &option_no_checkout,
66                  N_("don't create a checkout")),
67         OPT_BOOL(0, "bare", &option_bare, N_("create a bare repository")),
68         OPT_HIDDEN_BOOL(0, "naked", &option_bare,
69                         N_("create a bare repository")),
70         OPT_BOOL(0, "mirror", &option_mirror,
71                  N_("create a mirror repository (implies bare)")),
72         OPT_BOOL('l', "local", &option_local,
73                 N_("to clone from a local repository")),
74         OPT_BOOL(0, "no-hardlinks", &option_no_hardlinks,
75                     N_("don't use local hardlinks, always copy")),
76         OPT_BOOL('s', "shared", &option_shared,
77                     N_("setup as shared repository")),
78         OPT_BOOL(0, "recursive", &option_recursive,
79                     N_("initialize submodules in the clone")),
80         OPT_BOOL(0, "recurse-submodules", &option_recursive,
81                     N_("initialize submodules in the clone")),
82         OPT_STRING(0, "template", &option_template, N_("template-directory"),
83                    N_("directory from which templates will be used")),
84         OPT_CALLBACK(0 , "reference", &option_reference, N_("repo"),
85                      N_("reference repository"), &opt_parse_reference),
86         OPT_STRING('o', "origin", &option_origin, N_("name"),
87                    N_("use <name> instead of 'origin' to track upstream")),
88         OPT_STRING('b', "branch", &option_branch, N_("branch"),
89                    N_("checkout <branch> instead of the remote's HEAD")),
90         OPT_STRING('u', "upload-pack", &option_upload_pack, N_("path"),
91                    N_("path to git-upload-pack on the remote")),
92         OPT_STRING(0, "depth", &option_depth, N_("depth"),
93                     N_("create a shallow clone of that depth")),
94         OPT_BOOL(0, "single-branch", &option_single_branch,
95                     N_("clone only one branch, HEAD or --branch")),
96         OPT_STRING(0, "separate-git-dir", &real_git_dir, N_("gitdir"),
97                    N_("separate git dir from working tree")),
98         OPT_STRING_LIST('c', "config", &option_config, N_("key=value"),
99                         N_("set config inside the new repository")),
100         OPT_END()
101 };
102
103 static const char *argv_submodule[] = {
104         "submodule", "update", "--init", "--recursive", NULL
105 };
106
107 static char *get_repo_path(const char *repo, int *is_bundle)
108 {
109         static char *suffix[] = { "/.git", "", ".git/.git", ".git" };
110         static char *bundle_suffix[] = { ".bundle", "" };
111         struct stat st;
112         int i;
113
114         for (i = 0; i < ARRAY_SIZE(suffix); i++) {
115                 const char *path;
116                 path = mkpath("%s%s", repo, suffix[i]);
117                 if (stat(path, &st))
118                         continue;
119                 if (S_ISDIR(st.st_mode) && is_git_directory(path)) {
120                         *is_bundle = 0;
121                         return xstrdup(absolute_path(path));
122                 } else if (S_ISREG(st.st_mode) && st.st_size > 8) {
123                         /* Is it a "gitfile"? */
124                         char signature[8];
125                         int len, fd = open(path, O_RDONLY);
126                         if (fd < 0)
127                                 continue;
128                         len = read_in_full(fd, signature, 8);
129                         close(fd);
130                         if (len != 8 || strncmp(signature, "gitdir: ", 8))
131                                 continue;
132                         path = read_gitfile(path);
133                         if (path) {
134                                 *is_bundle = 0;
135                                 return xstrdup(absolute_path(path));
136                         }
137                 }
138         }
139
140         for (i = 0; i < ARRAY_SIZE(bundle_suffix); i++) {
141                 const char *path;
142                 path = mkpath("%s%s", repo, bundle_suffix[i]);
143                 if (!stat(path, &st) && S_ISREG(st.st_mode)) {
144                         *is_bundle = 1;
145                         return xstrdup(absolute_path(path));
146                 }
147         }
148
149         return NULL;
150 }
151
152 static char *guess_dir_name(const char *repo, int is_bundle, int is_bare)
153 {
154         const char *end = repo + strlen(repo), *start;
155         char *dir;
156
157         /*
158          * Strip trailing spaces, slashes and /.git
159          */
160         while (repo < end && (is_dir_sep(end[-1]) || isspace(end[-1])))
161                 end--;
162         if (end - repo > 5 && is_dir_sep(end[-5]) &&
163             !strncmp(end - 4, ".git", 4)) {
164                 end -= 5;
165                 while (repo < end && is_dir_sep(end[-1]))
166                         end--;
167         }
168
169         /*
170          * Find last component, but be prepared that repo could have
171          * the form  "remote.example.com:foo.git", i.e. no slash
172          * in the directory part.
173          */
174         start = end;
175         while (repo < start && !is_dir_sep(start[-1]) && start[-1] != ':')
176                 start--;
177
178         /*
179          * Strip .{bundle,git}.
180          */
181         if (is_bundle) {
182                 if (end - start > 7 && !strncmp(end - 7, ".bundle", 7))
183                         end -= 7;
184         } else {
185                 if (end - start > 4 && !strncmp(end - 4, ".git", 4))
186                         end -= 4;
187         }
188
189         if (is_bare) {
190                 struct strbuf result = STRBUF_INIT;
191                 strbuf_addf(&result, "%.*s.git", (int)(end - start), start);
192                 dir = strbuf_detach(&result, NULL);
193         } else
194                 dir = xstrndup(start, end - start);
195         /*
196          * Replace sequences of 'control' characters and whitespace
197          * with one ascii space, remove leading and trailing spaces.
198          */
199         if (*dir) {
200                 char *out = dir;
201                 int prev_space = 1 /* strip leading whitespace */;
202                 for (end = dir; *end; ++end) {
203                         char ch = *end;
204                         if ((unsigned char)ch < '\x20')
205                                 ch = '\x20';
206                         if (isspace(ch)) {
207                                 if (prev_space)
208                                         continue;
209                                 prev_space = 1;
210                         } else
211                                 prev_space = 0;
212                         *out++ = ch;
213                 }
214                 *out = '\0';
215                 if (out > dir && prev_space)
216                         out[-1] = '\0';
217         }
218         return dir;
219 }
220
221 static void strip_trailing_slashes(char *dir)
222 {
223         char *end = dir + strlen(dir);
224
225         while (dir < end - 1 && is_dir_sep(end[-1]))
226                 end--;
227         *end = '\0';
228 }
229
230 static int add_one_reference(struct string_list_item *item, void *cb_data)
231 {
232         char *ref_git;
233         const char *repo;
234         struct strbuf alternate = STRBUF_INIT;
235
236         /* Beware: read_gitfile(), real_path() and mkpath() return static buffer */
237         ref_git = xstrdup(real_path(item->string));
238
239         repo = read_gitfile(ref_git);
240         if (!repo)
241                 repo = read_gitfile(mkpath("%s/.git", ref_git));
242         if (repo) {
243                 free(ref_git);
244                 ref_git = xstrdup(repo);
245         }
246
247         if (!repo && is_directory(mkpath("%s/.git/objects", ref_git))) {
248                 char *ref_git_git = mkpathdup("%s/.git", ref_git);
249                 free(ref_git);
250                 ref_git = ref_git_git;
251         } else if (!is_directory(mkpath("%s/objects", ref_git)))
252                 die(_("reference repository '%s' is not a local repository."),
253                     item->string);
254
255         strbuf_addf(&alternate, "%s/objects", ref_git);
256         add_to_alternates_file(alternate.buf);
257         strbuf_release(&alternate);
258         free(ref_git);
259         return 0;
260 }
261
262 static void setup_reference(void)
263 {
264         for_each_string_list(&option_reference, add_one_reference, NULL);
265 }
266
267 static void copy_alternates(struct strbuf *src, struct strbuf *dst,
268                             const char *src_repo)
269 {
270         /*
271          * Read from the source objects/info/alternates file
272          * and copy the entries to corresponding file in the
273          * destination repository with add_to_alternates_file().
274          * Both src and dst have "$path/objects/info/alternates".
275          *
276          * Instead of copying bit-for-bit from the original,
277          * we need to append to existing one so that the already
278          * created entry via "clone -s" is not lost, and also
279          * to turn entries with paths relative to the original
280          * absolute, so that they can be used in the new repository.
281          */
282         FILE *in = fopen(src->buf, "r");
283         struct strbuf line = STRBUF_INIT;
284
285         while (strbuf_getline(&line, in, '\n') != EOF) {
286                 char *abs_path, abs_buf[PATH_MAX];
287                 if (!line.len || line.buf[0] == '#')
288                         continue;
289                 if (is_absolute_path(line.buf)) {
290                         add_to_alternates_file(line.buf);
291                         continue;
292                 }
293                 abs_path = mkpath("%s/objects/%s", src_repo, line.buf);
294                 normalize_path_copy(abs_buf, abs_path);
295                 add_to_alternates_file(abs_buf);
296         }
297         strbuf_release(&line);
298         fclose(in);
299 }
300
301 static void copy_or_link_directory(struct strbuf *src, struct strbuf *dest,
302                                    const char *src_repo, int src_baselen)
303 {
304         struct dirent *de;
305         struct stat buf;
306         int src_len, dest_len;
307         DIR *dir;
308
309         dir = opendir(src->buf);
310         if (!dir)
311                 die_errno(_("failed to open '%s'"), src->buf);
312
313         if (mkdir(dest->buf, 0777)) {
314                 if (errno != EEXIST)
315                         die_errno(_("failed to create directory '%s'"), dest->buf);
316                 else if (stat(dest->buf, &buf))
317                         die_errno(_("failed to stat '%s'"), dest->buf);
318                 else if (!S_ISDIR(buf.st_mode))
319                         die(_("%s exists and is not a directory"), dest->buf);
320         }
321
322         strbuf_addch(src, '/');
323         src_len = src->len;
324         strbuf_addch(dest, '/');
325         dest_len = dest->len;
326
327         while ((de = readdir(dir)) != NULL) {
328                 strbuf_setlen(src, src_len);
329                 strbuf_addstr(src, de->d_name);
330                 strbuf_setlen(dest, dest_len);
331                 strbuf_addstr(dest, de->d_name);
332                 if (stat(src->buf, &buf)) {
333                         warning (_("failed to stat %s\n"), src->buf);
334                         continue;
335                 }
336                 if (S_ISDIR(buf.st_mode)) {
337                         if (de->d_name[0] != '.')
338                                 copy_or_link_directory(src, dest,
339                                                        src_repo, src_baselen);
340                         continue;
341                 }
342
343                 /* Files that cannot be copied bit-for-bit... */
344                 if (!strcmp(src->buf + src_baselen, "/info/alternates")) {
345                         copy_alternates(src, dest, src_repo);
346                         continue;
347                 }
348
349                 if (unlink(dest->buf) && errno != ENOENT)
350                         die_errno(_("failed to unlink '%s'"), dest->buf);
351                 if (!option_no_hardlinks) {
352                         if (!link(src->buf, dest->buf))
353                                 continue;
354                         if (option_local > 0)
355                                 die_errno(_("failed to create link '%s'"), dest->buf);
356                         option_no_hardlinks = 1;
357                 }
358                 if (copy_file_with_time(dest->buf, src->buf, 0666))
359                         die_errno(_("failed to copy file to '%s'"), dest->buf);
360         }
361         closedir(dir);
362 }
363
364 static void clone_local(const char *src_repo, const char *dest_repo)
365 {
366         if (option_shared) {
367                 struct strbuf alt = STRBUF_INIT;
368                 strbuf_addf(&alt, "%s/objects", src_repo);
369                 add_to_alternates_file(alt.buf);
370                 strbuf_release(&alt);
371         } else {
372                 struct strbuf src = STRBUF_INIT;
373                 struct strbuf dest = STRBUF_INIT;
374                 strbuf_addf(&src, "%s/objects", src_repo);
375                 strbuf_addf(&dest, "%s/objects", dest_repo);
376                 copy_or_link_directory(&src, &dest, src_repo, src.len);
377                 strbuf_release(&src);
378                 strbuf_release(&dest);
379         }
380
381         if (0 <= option_verbosity)
382                 fprintf(stderr, _("done.\n"));
383 }
384
385 static const char *junk_work_tree;
386 static const char *junk_git_dir;
387 static pid_t junk_pid;
388 static enum {
389         JUNK_LEAVE_NONE,
390         JUNK_LEAVE_REPO,
391         JUNK_LEAVE_ALL
392 } junk_mode = JUNK_LEAVE_NONE;
393
394 static const char junk_leave_repo_msg[] =
395 N_("Clone succeeded, but checkout failed.\n"
396    "You can inspect what was checked out with 'git status'\n"
397    "and retry the checkout with 'git checkout -f HEAD'\n");
398
399 static void remove_junk(void)
400 {
401         struct strbuf sb = STRBUF_INIT;
402
403         switch (junk_mode) {
404         case JUNK_LEAVE_REPO:
405                 warning("%s", _(junk_leave_repo_msg));
406                 /* fall-through */
407         case JUNK_LEAVE_ALL:
408                 return;
409         default:
410                 /* proceed to removal */
411                 break;
412         }
413
414         if (getpid() != junk_pid)
415                 return;
416         if (junk_git_dir) {
417                 strbuf_addstr(&sb, junk_git_dir);
418                 remove_dir_recursively(&sb, 0);
419                 strbuf_reset(&sb);
420         }
421         if (junk_work_tree) {
422                 strbuf_addstr(&sb, junk_work_tree);
423                 remove_dir_recursively(&sb, 0);
424                 strbuf_reset(&sb);
425         }
426 }
427
428 static void remove_junk_on_signal(int signo)
429 {
430         remove_junk();
431         sigchain_pop(signo);
432         raise(signo);
433 }
434
435 static struct ref *find_remote_branch(const struct ref *refs, const char *branch)
436 {
437         struct ref *ref;
438         struct strbuf head = STRBUF_INIT;
439         strbuf_addstr(&head, "refs/heads/");
440         strbuf_addstr(&head, branch);
441         ref = find_ref_by_name(refs, head.buf);
442         strbuf_release(&head);
443
444         if (ref)
445                 return ref;
446
447         strbuf_addstr(&head, "refs/tags/");
448         strbuf_addstr(&head, branch);
449         ref = find_ref_by_name(refs, head.buf);
450         strbuf_release(&head);
451
452         return ref;
453 }
454
455 static struct ref *wanted_peer_refs(const struct ref *refs,
456                 struct refspec *refspec)
457 {
458         struct ref *head = copy_ref(find_ref_by_name(refs, "HEAD"));
459         struct ref *local_refs = head;
460         struct ref **tail = head ? &head->next : &local_refs;
461
462         if (option_single_branch) {
463                 struct ref *remote_head = NULL;
464
465                 if (!option_branch)
466                         remote_head = guess_remote_head(head, refs, 0);
467                 else {
468                         local_refs = NULL;
469                         tail = &local_refs;
470                         remote_head = copy_ref(find_remote_branch(refs, option_branch));
471                 }
472
473                 if (!remote_head && option_branch)
474                         warning(_("Could not find remote branch %s to clone."),
475                                 option_branch);
476                 else {
477                         get_fetch_map(remote_head, refspec, &tail, 0);
478
479                         /* if --branch=tag, pull the requested tag explicitly */
480                         get_fetch_map(remote_head, tag_refspec, &tail, 0);
481                 }
482         } else
483                 get_fetch_map(refs, refspec, &tail, 0);
484
485         if (!option_mirror && !option_single_branch)
486                 get_fetch_map(refs, tag_refspec, &tail, 0);
487
488         return local_refs;
489 }
490
491 static void write_remote_refs(const struct ref *local_refs)
492 {
493         const struct ref *r;
494
495         lock_packed_refs(LOCK_DIE_ON_ERROR);
496
497         for (r = local_refs; r; r = r->next) {
498                 if (!r->peer_ref)
499                         continue;
500                 add_packed_ref(r->peer_ref->name, r->old_sha1);
501         }
502
503         if (commit_packed_refs())
504                 die_errno("unable to overwrite old ref-pack file");
505 }
506
507 static void write_followtags(const struct ref *refs, const char *msg)
508 {
509         const struct ref *ref;
510         for (ref = refs; ref; ref = ref->next) {
511                 if (prefixcmp(ref->name, "refs/tags/"))
512                         continue;
513                 if (!suffixcmp(ref->name, "^{}"))
514                         continue;
515                 if (!has_sha1_file(ref->old_sha1))
516                         continue;
517                 update_ref(msg, ref->name, ref->old_sha1,
518                            NULL, 0, DIE_ON_ERR);
519         }
520 }
521
522 static int iterate_ref_map(void *cb_data, unsigned char sha1[20])
523 {
524         struct ref **rm = cb_data;
525         struct ref *ref = *rm;
526
527         /*
528          * Skip anything missing a peer_ref, which we are not
529          * actually going to write a ref for.
530          */
531         while (ref && !ref->peer_ref)
532                 ref = ref->next;
533         /* Returning -1 notes "end of list" to the caller. */
534         if (!ref)
535                 return -1;
536
537         hashcpy(sha1, ref->old_sha1);
538         *rm = ref->next;
539         return 0;
540 }
541
542 static void update_remote_refs(const struct ref *refs,
543                                const struct ref *mapped_refs,
544                                const struct ref *remote_head_points_at,
545                                const char *branch_top,
546                                const char *msg,
547                                struct transport *transport,
548                                int check_connectivity)
549 {
550         const struct ref *rm = mapped_refs;
551
552         if (check_connectivity) {
553                 if (transport->progress)
554                         fprintf(stderr, _("Checking connectivity... "));
555                 if (check_everything_connected_with_transport(iterate_ref_map,
556                                                               0, &rm, transport))
557                         die(_("remote did not send all necessary objects"));
558                 if (transport->progress)
559                         fprintf(stderr, _("done.\n"));
560         }
561
562         if (refs) {
563                 write_remote_refs(mapped_refs);
564                 if (option_single_branch)
565                         write_followtags(refs, msg);
566         }
567
568         if (remote_head_points_at && !option_bare) {
569                 struct strbuf head_ref = STRBUF_INIT;
570                 strbuf_addstr(&head_ref, branch_top);
571                 strbuf_addstr(&head_ref, "HEAD");
572                 create_symref(head_ref.buf,
573                               remote_head_points_at->peer_ref->name,
574                               msg);
575         }
576 }
577
578 static void update_head(const struct ref *our, const struct ref *remote,
579                         const char *msg)
580 {
581         if (our && !prefixcmp(our->name, "refs/heads/")) {
582                 /* Local default branch link */
583                 create_symref("HEAD", our->name, NULL);
584                 if (!option_bare) {
585                         const char *head = skip_prefix(our->name, "refs/heads/");
586                         update_ref(msg, "HEAD", our->old_sha1, NULL, 0, DIE_ON_ERR);
587                         install_branch_config(0, head, option_origin, our->name);
588                 }
589         } else if (our) {
590                 struct commit *c = lookup_commit_reference(our->old_sha1);
591                 /* --branch specifies a non-branch (i.e. tags), detach HEAD */
592                 update_ref(msg, "HEAD", c->object.sha1,
593                            NULL, REF_NODEREF, DIE_ON_ERR);
594         } else if (remote) {
595                 /*
596                  * We know remote HEAD points to a non-branch, or
597                  * HEAD points to a branch but we don't know which one.
598                  * Detach HEAD in all these cases.
599                  */
600                 update_ref(msg, "HEAD", remote->old_sha1,
601                            NULL, REF_NODEREF, DIE_ON_ERR);
602         }
603 }
604
605 static int checkout(void)
606 {
607         unsigned char sha1[20];
608         char *head;
609         struct lock_file *lock_file;
610         struct unpack_trees_options opts;
611         struct tree *tree;
612         struct tree_desc t;
613         int err = 0, fd;
614
615         if (option_no_checkout)
616                 return 0;
617
618         head = resolve_refdup("HEAD", sha1, 1, NULL);
619         if (!head) {
620                 warning(_("remote HEAD refers to nonexistent ref, "
621                           "unable to checkout.\n"));
622                 return 0;
623         }
624         if (!strcmp(head, "HEAD")) {
625                 if (advice_detached_head)
626                         detach_advice(sha1_to_hex(sha1));
627         } else {
628                 if (prefixcmp(head, "refs/heads/"))
629                         die(_("HEAD not found below refs/heads!"));
630         }
631         free(head);
632
633         /* We need to be in the new work tree for the checkout */
634         setup_work_tree();
635
636         lock_file = xcalloc(1, sizeof(struct lock_file));
637         fd = hold_locked_index(lock_file, 1);
638
639         memset(&opts, 0, sizeof opts);
640         opts.update = 1;
641         opts.merge = 1;
642         opts.fn = oneway_merge;
643         opts.verbose_update = (option_verbosity >= 0);
644         opts.src_index = &the_index;
645         opts.dst_index = &the_index;
646
647         tree = parse_tree_indirect(sha1);
648         parse_tree(tree);
649         init_tree_desc(&t, tree->buffer, tree->size);
650         if (unpack_trees(1, &t, &opts) < 0)
651                 die(_("unable to checkout working tree"));
652
653         if (write_cache(fd, active_cache, active_nr) ||
654             commit_locked_index(lock_file))
655                 die(_("unable to write new index file"));
656
657         err |= run_hook(NULL, "post-checkout", sha1_to_hex(null_sha1),
658                         sha1_to_hex(sha1), "1", NULL);
659
660         if (!err && option_recursive)
661                 err = run_command_v_opt(argv_submodule, RUN_GIT_CMD);
662
663         return err;
664 }
665
666 static int write_one_config(const char *key, const char *value, void *data)
667 {
668         return git_config_set_multivar(key, value ? value : "true", "^$", 0);
669 }
670
671 static void write_config(struct string_list *config)
672 {
673         int i;
674
675         for (i = 0; i < config->nr; i++) {
676                 if (git_config_parse_parameter(config->items[i].string,
677                                                write_one_config, NULL) < 0)
678                         die("unable to write parameters to config file");
679         }
680 }
681
682 static void write_refspec_config(const char* src_ref_prefix,
683                 const struct ref* our_head_points_at,
684                 const struct ref* remote_head_points_at, struct strbuf* branch_top)
685 {
686         struct strbuf key = STRBUF_INIT;
687         struct strbuf value = STRBUF_INIT;
688
689         if (option_mirror || !option_bare) {
690                 if (option_single_branch && !option_mirror) {
691                         if (option_branch) {
692                                 if (strstr(our_head_points_at->name, "refs/tags/"))
693                                         strbuf_addf(&value, "+%s:%s", our_head_points_at->name,
694                                                 our_head_points_at->name);
695                                 else
696                                         strbuf_addf(&value, "+%s:%s%s", our_head_points_at->name,
697                                                 branch_top->buf, option_branch);
698                         } else if (remote_head_points_at) {
699                                 strbuf_addf(&value, "+%s:%s%s", remote_head_points_at->name,
700                                                 branch_top->buf,
701                                                 skip_prefix(remote_head_points_at->name, "refs/heads/"));
702                         }
703                         /*
704                          * otherwise, the next "git fetch" will
705                          * simply fetch from HEAD without updating
706                          * any remote-tracking branch, which is what
707                          * we want.
708                          */
709                 } else {
710                         strbuf_addf(&value, "+%s*:%s*", src_ref_prefix, branch_top->buf);
711                 }
712                 /* Configure the remote */
713                 if (value.len) {
714                         strbuf_addf(&key, "remote.%s.fetch", option_origin);
715                         git_config_set_multivar(key.buf, value.buf, "^$", 0);
716                         strbuf_reset(&key);
717
718                         if (option_mirror) {
719                                 strbuf_addf(&key, "remote.%s.mirror", option_origin);
720                                 git_config_set(key.buf, "true");
721                                 strbuf_reset(&key);
722                         }
723                 }
724         }
725
726         strbuf_release(&key);
727         strbuf_release(&value);
728 }
729
730 int cmd_clone(int argc, const char **argv, const char *prefix)
731 {
732         int is_bundle = 0, is_local;
733         struct stat buf;
734         const char *repo_name, *repo, *work_tree, *git_dir;
735         char *path, *dir;
736         int dest_exists;
737         const struct ref *refs, *remote_head;
738         const struct ref *remote_head_points_at;
739         const struct ref *our_head_points_at;
740         struct ref *mapped_refs;
741         const struct ref *ref;
742         struct strbuf key = STRBUF_INIT, value = STRBUF_INIT;
743         struct strbuf branch_top = STRBUF_INIT, reflog_msg = STRBUF_INIT;
744         struct transport *transport = NULL;
745         const char *src_ref_prefix = "refs/heads/";
746         struct remote *remote;
747         int err = 0, complete_refs_before_fetch = 1;
748
749         struct refspec *refspec;
750         const char *fetch_pattern;
751
752         junk_pid = getpid();
753
754         packet_trace_identity("clone");
755         argc = parse_options(argc, argv, prefix, builtin_clone_options,
756                              builtin_clone_usage, 0);
757
758         if (argc > 2)
759                 usage_msg_opt(_("Too many arguments."),
760                         builtin_clone_usage, builtin_clone_options);
761
762         if (argc == 0)
763                 usage_msg_opt(_("You must specify a repository to clone."),
764                         builtin_clone_usage, builtin_clone_options);
765
766         if (option_single_branch == -1)
767                 option_single_branch = option_depth ? 1 : 0;
768
769         if (option_mirror)
770                 option_bare = 1;
771
772         if (option_bare) {
773                 if (option_origin)
774                         die(_("--bare and --origin %s options are incompatible."),
775                             option_origin);
776                 if (real_git_dir)
777                         die(_("--bare and --separate-git-dir are incompatible."));
778                 option_no_checkout = 1;
779         }
780
781         if (!option_origin)
782                 option_origin = "origin";
783
784         repo_name = argv[0];
785
786         path = get_repo_path(repo_name, &is_bundle);
787         if (path)
788                 repo = xstrdup(absolute_path(repo_name));
789         else if (!strchr(repo_name, ':'))
790                 die(_("repository '%s' does not exist"), repo_name);
791         else
792                 repo = repo_name;
793         is_local = option_local != 0 && path && !is_bundle;
794         if (is_local && option_depth)
795                 warning(_("--depth is ignored in local clones; use file:// instead."));
796         if (option_local > 0 && !is_local)
797                 warning(_("--local is ignored"));
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         if (!option_bare) {
832                 junk_work_tree = work_tree;
833                 if (safe_create_leading_directories_const(work_tree) < 0)
834                         die_errno(_("could not create leading directories of '%s'"),
835                                   work_tree);
836                 if (!dest_exists && mkdir(work_tree, 0777))
837                         die_errno(_("could not create work tree dir '%s'."),
838                                   work_tree);
839                 set_git_work_tree(work_tree);
840         }
841         junk_git_dir = git_dir;
842         atexit(remove_junk);
843         sigchain_push_common(remove_junk_on_signal);
844
845         if (safe_create_leading_directories_const(git_dir) < 0)
846                 die(_("could not create leading directories of '%s'"), git_dir);
847
848         set_git_dir_init(git_dir, real_git_dir, 0);
849         if (real_git_dir) {
850                 git_dir = real_git_dir;
851                 junk_git_dir = real_git_dir;
852         }
853
854         if (0 <= option_verbosity) {
855                 if (option_bare)
856                         fprintf(stderr, _("Cloning into bare repository '%s'...\n"), dir);
857                 else
858                         fprintf(stderr, _("Cloning into '%s'...\n"), dir);
859         }
860         init_db(option_template, INIT_DB_QUIET);
861         write_config(&option_config);
862
863         git_config(git_default_config, NULL);
864
865         if (option_bare) {
866                 if (option_mirror)
867                         src_ref_prefix = "refs/";
868                 strbuf_addstr(&branch_top, src_ref_prefix);
869
870                 git_config_set("core.bare", "true");
871         } else {
872                 strbuf_addf(&branch_top, "refs/remotes/%s/", option_origin);
873         }
874
875         strbuf_addf(&value, "+%s*:%s*", src_ref_prefix, branch_top.buf);
876         strbuf_addf(&key, "remote.%s.url", option_origin);
877         git_config_set(key.buf, repo);
878         strbuf_reset(&key);
879
880         if (option_reference.nr)
881                 setup_reference();
882
883         fetch_pattern = value.buf;
884         refspec = parse_fetch_refspec(1, &fetch_pattern);
885
886         strbuf_reset(&value);
887
888         remote = remote_get(option_origin);
889         transport = transport_get(remote, remote->url[0]);
890
891         if (!transport->get_refs_list || (!is_local && !transport->fetch))
892                 die(_("Don't know how to clone %s"), transport->url);
893
894         transport_set_option(transport, TRANS_OPT_KEEP, "yes");
895
896         if (option_depth)
897                 transport_set_option(transport, TRANS_OPT_DEPTH,
898                                      option_depth);
899         if (option_single_branch)
900                 transport_set_option(transport, TRANS_OPT_FOLLOWTAGS, "1");
901
902         transport_set_verbosity(transport, option_verbosity, option_progress);
903
904         if (option_upload_pack)
905                 transport_set_option(transport, TRANS_OPT_UPLOADPACK,
906                                      option_upload_pack);
907
908         if (transport->smart_options && !option_depth)
909                 transport->smart_options->check_self_contained_and_connected = 1;
910
911         refs = transport_get_remote_refs(transport);
912
913         if (refs) {
914                 mapped_refs = wanted_peer_refs(refs, refspec);
915                 /*
916                  * transport_get_remote_refs() may return refs with null sha-1
917                  * in mapped_refs (see struct transport->get_refs_list
918                  * comment). In that case we need fetch it early because
919                  * remote_head code below relies on it.
920                  *
921                  * for normal clones, transport_get_remote_refs() should
922                  * return reliable ref set, we can delay cloning until after
923                  * remote HEAD check.
924                  */
925                 for (ref = refs; ref; ref = ref->next)
926                         if (is_null_sha1(ref->old_sha1)) {
927                                 complete_refs_before_fetch = 0;
928                                 break;
929                         }
930
931                 if (!is_local && !complete_refs_before_fetch)
932                         transport_fetch_refs(transport, mapped_refs);
933
934                 remote_head = find_ref_by_name(refs, "HEAD");
935                 remote_head_points_at =
936                         guess_remote_head(remote_head, mapped_refs, 0);
937
938                 if (option_branch) {
939                         our_head_points_at =
940                                 find_remote_branch(mapped_refs, option_branch);
941
942                         if (!our_head_points_at)
943                                 die(_("Remote branch %s not found in upstream %s"),
944                                     option_branch, option_origin);
945                 }
946                 else
947                         our_head_points_at = remote_head_points_at;
948         }
949         else {
950                 if (option_branch)
951                         die(_("Remote branch %s not found in upstream %s"),
952                                         option_branch, option_origin);
953
954                 warning(_("You appear to have cloned an empty repository."));
955                 mapped_refs = NULL;
956                 our_head_points_at = NULL;
957                 remote_head_points_at = NULL;
958                 remote_head = NULL;
959                 option_no_checkout = 1;
960                 if (!option_bare)
961                         install_branch_config(0, "master", option_origin,
962                                               "refs/heads/master");
963         }
964
965         write_refspec_config(src_ref_prefix, our_head_points_at,
966                         remote_head_points_at, &branch_top);
967
968         if (is_local)
969                 clone_local(path, git_dir);
970         else if (refs && complete_refs_before_fetch)
971                 transport_fetch_refs(transport, mapped_refs);
972
973         update_remote_refs(refs, mapped_refs, remote_head_points_at,
974                            branch_top.buf, reflog_msg.buf, transport, !is_local);
975
976         update_head(our_head_points_at, remote_head, reflog_msg.buf);
977
978         transport_unlock_pack(transport);
979         transport_disconnect(transport);
980
981         junk_mode = JUNK_LEAVE_REPO;
982         err = checkout();
983
984         strbuf_release(&reflog_msg);
985         strbuf_release(&branch_top);
986         strbuf_release(&key);
987         strbuf_release(&value);
988         junk_mode = JUNK_LEAVE_ALL;
989         return err;
990 }