Merge branch 'jk/xmalloc'
[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 #define USE_THE_INDEX_COMPATIBILITY_MACROS
12 #include "builtin.h"
13 #include "config.h"
14 #include "lockfile.h"
15 #include "parse-options.h"
16 #include "fetch-pack.h"
17 #include "refs.h"
18 #include "refspec.h"
19 #include "object-store.h"
20 #include "tree.h"
21 #include "tree-walk.h"
22 #include "unpack-trees.h"
23 #include "transport.h"
24 #include "strbuf.h"
25 #include "dir.h"
26 #include "sigchain.h"
27 #include "branch.h"
28 #include "remote.h"
29 #include "run-command.h"
30 #include "connected.h"
31 #include "packfile.h"
32 #include "list-objects-filter-options.h"
33 #include "object-store.h"
34
35 /*
36  * Overall FIXMEs:
37  *  - respect DB_ENVIRONMENT for .git/objects.
38  *
39  * Implementation notes:
40  *  - dropping use-separate-remote and no-separate-remote compatibility
41  *
42  */
43 static const char * const builtin_clone_usage[] = {
44         N_("git clone [<options>] [--] <repo> [<dir>]"),
45         NULL
46 };
47
48 static int option_no_checkout, option_bare, option_mirror, option_single_branch = -1;
49 static int option_local = -1, option_no_hardlinks, option_shared;
50 static int option_no_tags;
51 static int option_shallow_submodules;
52 static int deepen;
53 static char *option_template, *option_depth, *option_since;
54 static char *option_origin = NULL;
55 static char *option_branch = NULL;
56 static struct string_list option_not = STRING_LIST_INIT_NODUP;
57 static const char *real_git_dir;
58 static char *option_upload_pack = "git-upload-pack";
59 static int option_verbosity;
60 static int option_progress = -1;
61 static enum transport_family family;
62 static struct string_list option_config = STRING_LIST_INIT_NODUP;
63 static struct string_list option_required_reference = STRING_LIST_INIT_NODUP;
64 static struct string_list option_optional_reference = STRING_LIST_INIT_NODUP;
65 static int option_dissociate;
66 static int max_jobs = -1;
67 static struct string_list option_recurse_submodules = STRING_LIST_INIT_NODUP;
68 static struct list_objects_filter_options filter_options;
69
70 static int recurse_submodules_cb(const struct option *opt,
71                                  const char *arg, int unset)
72 {
73         if (unset)
74                 string_list_clear((struct string_list *)opt->value, 0);
75         else if (arg)
76                 string_list_append((struct string_list *)opt->value, arg);
77         else
78                 string_list_append((struct string_list *)opt->value,
79                                    (const char *)opt->defval);
80
81         return 0;
82 }
83
84 static struct option builtin_clone_options[] = {
85         OPT__VERBOSITY(&option_verbosity),
86         OPT_BOOL(0, "progress", &option_progress,
87                  N_("force progress reporting")),
88         OPT_BOOL('n', "no-checkout", &option_no_checkout,
89                  N_("don't create a checkout")),
90         OPT_BOOL(0, "bare", &option_bare, N_("create a bare repository")),
91         OPT_HIDDEN_BOOL(0, "naked", &option_bare,
92                         N_("create a bare repository")),
93         OPT_BOOL(0, "mirror", &option_mirror,
94                  N_("create a mirror repository (implies bare)")),
95         OPT_BOOL('l', "local", &option_local,
96                 N_("to clone from a local repository")),
97         OPT_BOOL(0, "no-hardlinks", &option_no_hardlinks,
98                     N_("don't use local hardlinks, always copy")),
99         OPT_BOOL('s', "shared", &option_shared,
100                     N_("setup as shared repository")),
101         { OPTION_CALLBACK, 0, "recursive", &option_recurse_submodules,
102           N_("pathspec"), N_("initialize submodules in the clone"),
103           PARSE_OPT_OPTARG | PARSE_OPT_HIDDEN, recurse_submodules_cb,
104           (intptr_t)"." },
105         { OPTION_CALLBACK, 0, "recurse-submodules", &option_recurse_submodules,
106           N_("pathspec"), N_("initialize submodules in the clone"),
107           PARSE_OPT_OPTARG, recurse_submodules_cb, (intptr_t)"." },
108         OPT_INTEGER('j', "jobs", &max_jobs,
109                     N_("number of submodules cloned in parallel")),
110         OPT_STRING(0, "template", &option_template, N_("template-directory"),
111                    N_("directory from which templates will be used")),
112         OPT_STRING_LIST(0, "reference", &option_required_reference, N_("repo"),
113                         N_("reference repository")),
114         OPT_STRING_LIST(0, "reference-if-able", &option_optional_reference,
115                         N_("repo"), N_("reference repository")),
116         OPT_BOOL(0, "dissociate", &option_dissociate,
117                  N_("use --reference only while cloning")),
118         OPT_STRING('o', "origin", &option_origin, N_("name"),
119                    N_("use <name> instead of 'origin' to track upstream")),
120         OPT_STRING('b', "branch", &option_branch, N_("branch"),
121                    N_("checkout <branch> instead of the remote's HEAD")),
122         OPT_STRING('u', "upload-pack", &option_upload_pack, N_("path"),
123                    N_("path to git-upload-pack on the remote")),
124         OPT_STRING(0, "depth", &option_depth, N_("depth"),
125                     N_("create a shallow clone of that depth")),
126         OPT_STRING(0, "shallow-since", &option_since, N_("time"),
127                     N_("create a shallow clone since a specific time")),
128         OPT_STRING_LIST(0, "shallow-exclude", &option_not, N_("revision"),
129                         N_("deepen history of shallow clone, excluding rev")),
130         OPT_BOOL(0, "single-branch", &option_single_branch,
131                     N_("clone only one branch, HEAD or --branch")),
132         OPT_BOOL(0, "no-tags", &option_no_tags,
133                  N_("don't clone any tags, and make later fetches not to follow them")),
134         OPT_BOOL(0, "shallow-submodules", &option_shallow_submodules,
135                     N_("any cloned submodules will be shallow")),
136         OPT_STRING(0, "separate-git-dir", &real_git_dir, N_("gitdir"),
137                    N_("separate git dir from working tree")),
138         OPT_STRING_LIST('c', "config", &option_config, N_("key=value"),
139                         N_("set config inside the new repository")),
140         OPT_SET_INT('4', "ipv4", &family, N_("use IPv4 addresses only"),
141                         TRANSPORT_FAMILY_IPV4),
142         OPT_SET_INT('6', "ipv6", &family, N_("use IPv6 addresses only"),
143                         TRANSPORT_FAMILY_IPV6),
144         OPT_PARSE_LIST_OBJECTS_FILTER(&filter_options),
145         OPT_END()
146 };
147
148 static const char *get_repo_path_1(struct strbuf *path, int *is_bundle)
149 {
150         static char *suffix[] = { "/.git", "", ".git/.git", ".git" };
151         static char *bundle_suffix[] = { ".bundle", "" };
152         size_t baselen = path->len;
153         struct stat st;
154         int i;
155
156         for (i = 0; i < ARRAY_SIZE(suffix); i++) {
157                 strbuf_setlen(path, baselen);
158                 strbuf_addstr(path, suffix[i]);
159                 if (stat(path->buf, &st))
160                         continue;
161                 if (S_ISDIR(st.st_mode) && is_git_directory(path->buf)) {
162                         *is_bundle = 0;
163                         return path->buf;
164                 } else if (S_ISREG(st.st_mode) && st.st_size > 8) {
165                         /* Is it a "gitfile"? */
166                         char signature[8];
167                         const char *dst;
168                         int len, fd = open(path->buf, O_RDONLY);
169                         if (fd < 0)
170                                 continue;
171                         len = read_in_full(fd, signature, 8);
172                         close(fd);
173                         if (len != 8 || strncmp(signature, "gitdir: ", 8))
174                                 continue;
175                         dst = read_gitfile(path->buf);
176                         if (dst) {
177                                 *is_bundle = 0;
178                                 return dst;
179                         }
180                 }
181         }
182
183         for (i = 0; i < ARRAY_SIZE(bundle_suffix); i++) {
184                 strbuf_setlen(path, baselen);
185                 strbuf_addstr(path, bundle_suffix[i]);
186                 if (!stat(path->buf, &st) && S_ISREG(st.st_mode)) {
187                         *is_bundle = 1;
188                         return path->buf;
189                 }
190         }
191
192         return NULL;
193 }
194
195 static char *get_repo_path(const char *repo, int *is_bundle)
196 {
197         struct strbuf path = STRBUF_INIT;
198         const char *raw;
199         char *canon;
200
201         strbuf_addstr(&path, repo);
202         raw = get_repo_path_1(&path, is_bundle);
203         canon = raw ? absolute_pathdup(raw) : NULL;
204         strbuf_release(&path);
205         return canon;
206 }
207
208 static char *guess_dir_name(const char *repo, int is_bundle, int is_bare)
209 {
210         const char *end = repo + strlen(repo), *start, *ptr;
211         size_t len;
212         char *dir;
213
214         /*
215          * Skip scheme.
216          */
217         start = strstr(repo, "://");
218         if (start == NULL)
219                 start = repo;
220         else
221                 start += 3;
222
223         /*
224          * Skip authentication data. The stripping does happen
225          * greedily, such that we strip up to the last '@' inside
226          * the host part.
227          */
228         for (ptr = start; ptr < end && !is_dir_sep(*ptr); ptr++) {
229                 if (*ptr == '@')
230                         start = ptr + 1;
231         }
232
233         /*
234          * Strip trailing spaces, slashes and /.git
235          */
236         while (start < end && (is_dir_sep(end[-1]) || isspace(end[-1])))
237                 end--;
238         if (end - start > 5 && is_dir_sep(end[-5]) &&
239             !strncmp(end - 4, ".git", 4)) {
240                 end -= 5;
241                 while (start < end && is_dir_sep(end[-1]))
242                         end--;
243         }
244
245         /*
246          * Strip trailing port number if we've got only a
247          * hostname (that is, there is no dir separator but a
248          * colon). This check is required such that we do not
249          * strip URI's like '/foo/bar:2222.git', which should
250          * result in a dir '2222' being guessed due to backwards
251          * compatibility.
252          */
253         if (memchr(start, '/', end - start) == NULL
254             && memchr(start, ':', end - start) != NULL) {
255                 ptr = end;
256                 while (start < ptr && isdigit(ptr[-1]) && ptr[-1] != ':')
257                         ptr--;
258                 if (start < ptr && ptr[-1] == ':')
259                         end = ptr - 1;
260         }
261
262         /*
263          * Find last component. To remain backwards compatible we
264          * also regard colons as path separators, such that
265          * cloning a repository 'foo:bar.git' would result in a
266          * directory 'bar' being guessed.
267          */
268         ptr = end;
269         while (start < ptr && !is_dir_sep(ptr[-1]) && ptr[-1] != ':')
270                 ptr--;
271         start = ptr;
272
273         /*
274          * Strip .{bundle,git}.
275          */
276         len = end - start;
277         strip_suffix_mem(start, &len, is_bundle ? ".bundle" : ".git");
278
279         if (!len || (len == 1 && *start == '/'))
280                 die(_("No directory name could be guessed.\n"
281                       "Please specify a directory on the command line"));
282
283         if (is_bare)
284                 dir = xstrfmt("%.*s.git", (int)len, start);
285         else
286                 dir = xstrndup(start, len);
287         /*
288          * Replace sequences of 'control' characters and whitespace
289          * with one ascii space, remove leading and trailing spaces.
290          */
291         if (*dir) {
292                 char *out = dir;
293                 int prev_space = 1 /* strip leading whitespace */;
294                 for (end = dir; *end; ++end) {
295                         char ch = *end;
296                         if ((unsigned char)ch < '\x20')
297                                 ch = '\x20';
298                         if (isspace(ch)) {
299                                 if (prev_space)
300                                         continue;
301                                 prev_space = 1;
302                         } else
303                                 prev_space = 0;
304                         *out++ = ch;
305                 }
306                 *out = '\0';
307                 if (out > dir && prev_space)
308                         out[-1] = '\0';
309         }
310         return dir;
311 }
312
313 static void strip_trailing_slashes(char *dir)
314 {
315         char *end = dir + strlen(dir);
316
317         while (dir < end - 1 && is_dir_sep(end[-1]))
318                 end--;
319         *end = '\0';
320 }
321
322 static int add_one_reference(struct string_list_item *item, void *cb_data)
323 {
324         struct strbuf err = STRBUF_INIT;
325         int *required = cb_data;
326         char *ref_git = compute_alternate_path(item->string, &err);
327
328         if (!ref_git) {
329                 if (*required)
330                         die("%s", err.buf);
331                 else
332                         fprintf(stderr,
333                                 _("info: Could not add alternate for '%s': %s\n"),
334                                 item->string, err.buf);
335         } else {
336                 struct strbuf sb = STRBUF_INIT;
337                 strbuf_addf(&sb, "%s/objects", ref_git);
338                 add_to_alternates_file(sb.buf);
339                 strbuf_release(&sb);
340         }
341
342         strbuf_release(&err);
343         free(ref_git);
344         return 0;
345 }
346
347 static void setup_reference(void)
348 {
349         int required = 1;
350         for_each_string_list(&option_required_reference,
351                              add_one_reference, &required);
352         required = 0;
353         for_each_string_list(&option_optional_reference,
354                              add_one_reference, &required);
355 }
356
357 static void copy_alternates(struct strbuf *src, struct strbuf *dst,
358                             const char *src_repo)
359 {
360         /*
361          * Read from the source objects/info/alternates file
362          * and copy the entries to corresponding file in the
363          * destination repository with add_to_alternates_file().
364          * Both src and dst have "$path/objects/info/alternates".
365          *
366          * Instead of copying bit-for-bit from the original,
367          * we need to append to existing one so that the already
368          * created entry via "clone -s" is not lost, and also
369          * to turn entries with paths relative to the original
370          * absolute, so that they can be used in the new repository.
371          */
372         FILE *in = xfopen(src->buf, "r");
373         struct strbuf line = STRBUF_INIT;
374
375         while (strbuf_getline(&line, in) != EOF) {
376                 char *abs_path;
377                 if (!line.len || line.buf[0] == '#')
378                         continue;
379                 if (is_absolute_path(line.buf)) {
380                         add_to_alternates_file(line.buf);
381                         continue;
382                 }
383                 abs_path = mkpathdup("%s/objects/%s", src_repo, line.buf);
384                 if (!normalize_path_copy(abs_path, abs_path))
385                         add_to_alternates_file(abs_path);
386                 else
387                         warning("skipping invalid relative alternate: %s/%s",
388                                 src_repo, line.buf);
389                 free(abs_path);
390         }
391         strbuf_release(&line);
392         fclose(in);
393 }
394
395 static void copy_or_link_directory(struct strbuf *src, struct strbuf *dest,
396                                    const char *src_repo, int src_baselen)
397 {
398         struct dirent *de;
399         struct stat buf;
400         int src_len, dest_len;
401         DIR *dir;
402
403         dir = opendir(src->buf);
404         if (!dir)
405                 die_errno(_("failed to open '%s'"), src->buf);
406
407         if (mkdir(dest->buf, 0777)) {
408                 if (errno != EEXIST)
409                         die_errno(_("failed to create directory '%s'"), dest->buf);
410                 else if (stat(dest->buf, &buf))
411                         die_errno(_("failed to stat '%s'"), dest->buf);
412                 else if (!S_ISDIR(buf.st_mode))
413                         die(_("%s exists and is not a directory"), dest->buf);
414         }
415
416         strbuf_addch(src, '/');
417         src_len = src->len;
418         strbuf_addch(dest, '/');
419         dest_len = dest->len;
420
421         while ((de = readdir(dir)) != NULL) {
422                 strbuf_setlen(src, src_len);
423                 strbuf_addstr(src, de->d_name);
424                 strbuf_setlen(dest, dest_len);
425                 strbuf_addstr(dest, de->d_name);
426                 if (stat(src->buf, &buf)) {
427                         warning (_("failed to stat %s\n"), src->buf);
428                         continue;
429                 }
430                 if (S_ISDIR(buf.st_mode)) {
431                         if (de->d_name[0] != '.')
432                                 copy_or_link_directory(src, dest,
433                                                        src_repo, src_baselen);
434                         continue;
435                 }
436
437                 /* Files that cannot be copied bit-for-bit... */
438                 if (!strcmp(src->buf + src_baselen, "/info/alternates")) {
439                         copy_alternates(src, dest, src_repo);
440                         continue;
441                 }
442
443                 if (unlink(dest->buf) && errno != ENOENT)
444                         die_errno(_("failed to unlink '%s'"), dest->buf);
445                 if (!option_no_hardlinks) {
446                         if (!link(src->buf, dest->buf))
447                                 continue;
448                         if (option_local > 0)
449                                 die_errno(_("failed to create link '%s'"), dest->buf);
450                         option_no_hardlinks = 1;
451                 }
452                 if (copy_file_with_time(dest->buf, src->buf, 0666))
453                         die_errno(_("failed to copy file to '%s'"), dest->buf);
454         }
455         closedir(dir);
456 }
457
458 static void clone_local(const char *src_repo, const char *dest_repo)
459 {
460         if (option_shared) {
461                 struct strbuf alt = STRBUF_INIT;
462                 get_common_dir(&alt, src_repo);
463                 strbuf_addstr(&alt, "/objects");
464                 add_to_alternates_file(alt.buf);
465                 strbuf_release(&alt);
466         } else {
467                 struct strbuf src = STRBUF_INIT;
468                 struct strbuf dest = STRBUF_INIT;
469                 get_common_dir(&src, src_repo);
470                 get_common_dir(&dest, dest_repo);
471                 strbuf_addstr(&src, "/objects");
472                 strbuf_addstr(&dest, "/objects");
473                 copy_or_link_directory(&src, &dest, src_repo, src.len);
474                 strbuf_release(&src);
475                 strbuf_release(&dest);
476         }
477
478         if (0 <= option_verbosity)
479                 fprintf(stderr, _("done.\n"));
480 }
481
482 static const char *junk_work_tree;
483 static int junk_work_tree_flags;
484 static const char *junk_git_dir;
485 static int junk_git_dir_flags;
486 static enum {
487         JUNK_LEAVE_NONE,
488         JUNK_LEAVE_REPO,
489         JUNK_LEAVE_ALL
490 } junk_mode = JUNK_LEAVE_NONE;
491
492 static const char junk_leave_repo_msg[] =
493 N_("Clone succeeded, but checkout failed.\n"
494    "You can inspect what was checked out with 'git status'\n"
495    "and retry the checkout with 'git checkout -f HEAD'\n");
496
497 static void remove_junk(void)
498 {
499         struct strbuf sb = STRBUF_INIT;
500
501         switch (junk_mode) {
502         case JUNK_LEAVE_REPO:
503                 warning("%s", _(junk_leave_repo_msg));
504                 /* fall-through */
505         case JUNK_LEAVE_ALL:
506                 return;
507         default:
508                 /* proceed to removal */
509                 break;
510         }
511
512         if (junk_git_dir) {
513                 strbuf_addstr(&sb, junk_git_dir);
514                 remove_dir_recursively(&sb, junk_git_dir_flags);
515                 strbuf_reset(&sb);
516         }
517         if (junk_work_tree) {
518                 strbuf_addstr(&sb, junk_work_tree);
519                 remove_dir_recursively(&sb, junk_work_tree_flags);
520         }
521         strbuf_release(&sb);
522 }
523
524 static void remove_junk_on_signal(int signo)
525 {
526         remove_junk();
527         sigchain_pop(signo);
528         raise(signo);
529 }
530
531 static struct ref *find_remote_branch(const struct ref *refs, const char *branch)
532 {
533         struct ref *ref;
534         struct strbuf head = STRBUF_INIT;
535         strbuf_addstr(&head, "refs/heads/");
536         strbuf_addstr(&head, branch);
537         ref = find_ref_by_name(refs, head.buf);
538         strbuf_release(&head);
539
540         if (ref)
541                 return ref;
542
543         strbuf_addstr(&head, "refs/tags/");
544         strbuf_addstr(&head, branch);
545         ref = find_ref_by_name(refs, head.buf);
546         strbuf_release(&head);
547
548         return ref;
549 }
550
551 static struct ref *wanted_peer_refs(const struct ref *refs,
552                 struct refspec *refspec)
553 {
554         struct ref *head = copy_ref(find_ref_by_name(refs, "HEAD"));
555         struct ref *local_refs = head;
556         struct ref **tail = head ? &head->next : &local_refs;
557
558         if (option_single_branch) {
559                 struct ref *remote_head = NULL;
560
561                 if (!option_branch)
562                         remote_head = guess_remote_head(head, refs, 0);
563                 else {
564                         local_refs = NULL;
565                         tail = &local_refs;
566                         remote_head = copy_ref(find_remote_branch(refs, option_branch));
567                 }
568
569                 if (!remote_head && option_branch)
570                         warning(_("Could not find remote branch %s to clone."),
571                                 option_branch);
572                 else {
573                         int i;
574                         for (i = 0; i < refspec->nr; i++)
575                                 get_fetch_map(remote_head, &refspec->items[i],
576                                               &tail, 0);
577
578                         /* if --branch=tag, pull the requested tag explicitly */
579                         get_fetch_map(remote_head, tag_refspec, &tail, 0);
580                 }
581         } else {
582                 int i;
583                 for (i = 0; i < refspec->nr; i++)
584                         get_fetch_map(refs, &refspec->items[i], &tail, 0);
585         }
586
587         if (!option_mirror && !option_single_branch && !option_no_tags)
588                 get_fetch_map(refs, tag_refspec, &tail, 0);
589
590         return local_refs;
591 }
592
593 static void write_remote_refs(const struct ref *local_refs)
594 {
595         const struct ref *r;
596
597         struct ref_transaction *t;
598         struct strbuf err = STRBUF_INIT;
599
600         t = ref_transaction_begin(&err);
601         if (!t)
602                 die("%s", err.buf);
603
604         for (r = local_refs; r; r = r->next) {
605                 if (!r->peer_ref)
606                         continue;
607                 if (ref_transaction_create(t, r->peer_ref->name, &r->old_oid,
608                                            0, NULL, &err))
609                         die("%s", err.buf);
610         }
611
612         if (initial_ref_transaction_commit(t, &err))
613                 die("%s", err.buf);
614
615         strbuf_release(&err);
616         ref_transaction_free(t);
617 }
618
619 static void write_followtags(const struct ref *refs, const char *msg)
620 {
621         const struct ref *ref;
622         for (ref = refs; ref; ref = ref->next) {
623                 if (!starts_with(ref->name, "refs/tags/"))
624                         continue;
625                 if (ends_with(ref->name, "^{}"))
626                         continue;
627                 if (!has_object_file(&ref->old_oid))
628                         continue;
629                 update_ref(msg, ref->name, &ref->old_oid, NULL, 0,
630                            UPDATE_REFS_DIE_ON_ERR);
631         }
632 }
633
634 static int iterate_ref_map(void *cb_data, struct object_id *oid)
635 {
636         struct ref **rm = cb_data;
637         struct ref *ref = *rm;
638
639         /*
640          * Skip anything missing a peer_ref, which we are not
641          * actually going to write a ref for.
642          */
643         while (ref && !ref->peer_ref)
644                 ref = ref->next;
645         /* Returning -1 notes "end of list" to the caller. */
646         if (!ref)
647                 return -1;
648
649         oidcpy(oid, &ref->old_oid);
650         *rm = ref->next;
651         return 0;
652 }
653
654 static void update_remote_refs(const struct ref *refs,
655                                const struct ref *mapped_refs,
656                                const struct ref *remote_head_points_at,
657                                const char *branch_top,
658                                const char *msg,
659                                struct transport *transport,
660                                int check_connectivity)
661 {
662         const struct ref *rm = mapped_refs;
663
664         if (check_connectivity) {
665                 struct check_connected_options opt = CHECK_CONNECTED_INIT;
666
667                 opt.transport = transport;
668                 opt.progress = transport->progress;
669
670                 if (check_connected(iterate_ref_map, &rm, &opt))
671                         die(_("remote did not send all necessary objects"));
672         }
673
674         if (refs) {
675                 write_remote_refs(mapped_refs);
676                 if (option_single_branch && !option_no_tags)
677                         write_followtags(refs, msg);
678         }
679
680         if (remote_head_points_at && !option_bare) {
681                 struct strbuf head_ref = STRBUF_INIT;
682                 strbuf_addstr(&head_ref, branch_top);
683                 strbuf_addstr(&head_ref, "HEAD");
684                 if (create_symref(head_ref.buf,
685                                   remote_head_points_at->peer_ref->name,
686                                   msg) < 0)
687                         die(_("unable to update %s"), head_ref.buf);
688                 strbuf_release(&head_ref);
689         }
690 }
691
692 static void update_head(const struct ref *our, const struct ref *remote,
693                         const char *msg)
694 {
695         const char *head;
696         if (our && skip_prefix(our->name, "refs/heads/", &head)) {
697                 /* Local default branch link */
698                 if (create_symref("HEAD", our->name, NULL) < 0)
699                         die(_("unable to update HEAD"));
700                 if (!option_bare) {
701                         update_ref(msg, "HEAD", &our->old_oid, NULL, 0,
702                                    UPDATE_REFS_DIE_ON_ERR);
703                         install_branch_config(0, head, option_origin, our->name);
704                 }
705         } else if (our) {
706                 struct commit *c = lookup_commit_reference(the_repository,
707                                                            &our->old_oid);
708                 /* --branch specifies a non-branch (i.e. tags), detach HEAD */
709                 update_ref(msg, "HEAD", &c->object.oid, NULL, REF_NO_DEREF,
710                            UPDATE_REFS_DIE_ON_ERR);
711         } else if (remote) {
712                 /*
713                  * We know remote HEAD points to a non-branch, or
714                  * HEAD points to a branch but we don't know which one.
715                  * Detach HEAD in all these cases.
716                  */
717                 update_ref(msg, "HEAD", &remote->old_oid, NULL, REF_NO_DEREF,
718                            UPDATE_REFS_DIE_ON_ERR);
719         }
720 }
721
722 static int checkout(int submodule_progress)
723 {
724         struct object_id oid;
725         char *head;
726         struct lock_file lock_file = LOCK_INIT;
727         struct unpack_trees_options opts;
728         struct tree *tree;
729         struct tree_desc t;
730         int err = 0;
731
732         if (option_no_checkout)
733                 return 0;
734
735         head = resolve_refdup("HEAD", RESOLVE_REF_READING, &oid, NULL);
736         if (!head) {
737                 warning(_("remote HEAD refers to nonexistent ref, "
738                           "unable to checkout.\n"));
739                 return 0;
740         }
741         if (!strcmp(head, "HEAD")) {
742                 if (advice_detached_head)
743                         detach_advice(oid_to_hex(&oid));
744         } else {
745                 if (!starts_with(head, "refs/heads/"))
746                         die(_("HEAD not found below refs/heads!"));
747         }
748         free(head);
749
750         /* We need to be in the new work tree for the checkout */
751         setup_work_tree();
752
753         hold_locked_index(&lock_file, LOCK_DIE_ON_ERROR);
754
755         memset(&opts, 0, sizeof opts);
756         opts.update = 1;
757         opts.merge = 1;
758         opts.clone = 1;
759         opts.fn = oneway_merge;
760         opts.verbose_update = (option_verbosity >= 0);
761         opts.src_index = &the_index;
762         opts.dst_index = &the_index;
763
764         tree = parse_tree_indirect(&oid);
765         parse_tree(tree);
766         init_tree_desc(&t, tree->buffer, tree->size);
767         if (unpack_trees(1, &t, &opts) < 0)
768                 die(_("unable to checkout working tree"));
769
770         if (write_locked_index(&the_index, &lock_file, COMMIT_LOCK))
771                 die(_("unable to write new index file"));
772
773         err |= run_hook_le(NULL, "post-checkout", sha1_to_hex(null_sha1),
774                            oid_to_hex(&oid), "1", NULL);
775
776         if (!err && (option_recurse_submodules.nr > 0)) {
777                 struct argv_array args = ARGV_ARRAY_INIT;
778                 argv_array_pushl(&args, "submodule", "update", "--init", "--recursive", NULL);
779
780                 if (option_shallow_submodules == 1)
781                         argv_array_push(&args, "--depth=1");
782
783                 if (max_jobs != -1)
784                         argv_array_pushf(&args, "--jobs=%d", max_jobs);
785
786                 if (submodule_progress)
787                         argv_array_push(&args, "--progress");
788
789                 if (option_verbosity < 0)
790                         argv_array_push(&args, "--quiet");
791
792                 err = run_command_v_opt(args.argv, RUN_GIT_CMD);
793                 argv_array_clear(&args);
794         }
795
796         return err;
797 }
798
799 static int write_one_config(const char *key, const char *value, void *data)
800 {
801         return git_config_set_multivar_gently(key,
802                                               value ? value : "true",
803                                               CONFIG_REGEX_NONE, 0);
804 }
805
806 static void write_config(struct string_list *config)
807 {
808         int i;
809
810         for (i = 0; i < config->nr; i++) {
811                 if (git_config_parse_parameter(config->items[i].string,
812                                                write_one_config, NULL) < 0)
813                         die(_("unable to write parameters to config file"));
814         }
815 }
816
817 static void write_refspec_config(const char *src_ref_prefix,
818                 const struct ref *our_head_points_at,
819                 const struct ref *remote_head_points_at,
820                 struct strbuf *branch_top)
821 {
822         struct strbuf key = STRBUF_INIT;
823         struct strbuf value = STRBUF_INIT;
824
825         if (option_mirror || !option_bare) {
826                 if (option_single_branch && !option_mirror) {
827                         if (option_branch) {
828                                 if (starts_with(our_head_points_at->name, "refs/tags/"))
829                                         strbuf_addf(&value, "+%s:%s", our_head_points_at->name,
830                                                 our_head_points_at->name);
831                                 else
832                                         strbuf_addf(&value, "+%s:%s%s", our_head_points_at->name,
833                                                 branch_top->buf, option_branch);
834                         } else if (remote_head_points_at) {
835                                 const char *head = remote_head_points_at->name;
836                                 if (!skip_prefix(head, "refs/heads/", &head))
837                                         BUG("remote HEAD points at non-head?");
838
839                                 strbuf_addf(&value, "+%s:%s%s", remote_head_points_at->name,
840                                                 branch_top->buf, head);
841                         }
842                         /*
843                          * otherwise, the next "git fetch" will
844                          * simply fetch from HEAD without updating
845                          * any remote-tracking branch, which is what
846                          * we want.
847                          */
848                 } else {
849                         strbuf_addf(&value, "+%s*:%s*", src_ref_prefix, branch_top->buf);
850                 }
851                 /* Configure the remote */
852                 if (value.len) {
853                         strbuf_addf(&key, "remote.%s.fetch", option_origin);
854                         git_config_set_multivar(key.buf, value.buf, "^$", 0);
855                         strbuf_reset(&key);
856
857                         if (option_mirror) {
858                                 strbuf_addf(&key, "remote.%s.mirror", option_origin);
859                                 git_config_set(key.buf, "true");
860                                 strbuf_reset(&key);
861                         }
862                 }
863         }
864
865         strbuf_release(&key);
866         strbuf_release(&value);
867 }
868
869 static void dissociate_from_references(void)
870 {
871         static const char* argv[] = { "repack", "-a", "-d", NULL };
872         char *alternates = git_pathdup("objects/info/alternates");
873
874         if (!access(alternates, F_OK)) {
875                 if (run_command_v_opt(argv, RUN_GIT_CMD|RUN_COMMAND_NO_STDIN))
876                         die(_("cannot repack to clean up"));
877                 if (unlink(alternates) && errno != ENOENT)
878                         die_errno(_("cannot unlink temporary alternates file"));
879         }
880         free(alternates);
881 }
882
883 static int dir_exists(const char *path)
884 {
885         struct stat sb;
886         return !stat(path, &sb);
887 }
888
889 int cmd_clone(int argc, const char **argv, const char *prefix)
890 {
891         int is_bundle = 0, is_local;
892         const char *repo_name, *repo, *work_tree, *git_dir;
893         char *path, *dir;
894         int dest_exists;
895         const struct ref *refs, *remote_head;
896         const struct ref *remote_head_points_at;
897         const struct ref *our_head_points_at;
898         struct ref *mapped_refs;
899         const struct ref *ref;
900         struct strbuf key = STRBUF_INIT;
901         struct strbuf default_refspec = STRBUF_INIT;
902         struct strbuf branch_top = STRBUF_INIT, reflog_msg = STRBUF_INIT;
903         struct transport *transport = NULL;
904         const char *src_ref_prefix = "refs/heads/";
905         struct remote *remote;
906         int err = 0, complete_refs_before_fetch = 1;
907         int submodule_progress;
908
909         struct argv_array ref_prefixes = ARGV_ARRAY_INIT;
910
911         fetch_if_missing = 0;
912
913         packet_trace_identity("clone");
914         argc = parse_options(argc, argv, prefix, builtin_clone_options,
915                              builtin_clone_usage, 0);
916
917         if (argc > 2)
918                 usage_msg_opt(_("Too many arguments."),
919                         builtin_clone_usage, builtin_clone_options);
920
921         if (argc == 0)
922                 usage_msg_opt(_("You must specify a repository to clone."),
923                         builtin_clone_usage, builtin_clone_options);
924
925         if (option_depth || option_since || option_not.nr)
926                 deepen = 1;
927         if (option_single_branch == -1)
928                 option_single_branch = deepen ? 1 : 0;
929
930         if (option_mirror)
931                 option_bare = 1;
932
933         if (option_bare) {
934                 if (option_origin)
935                         die(_("--bare and --origin %s options are incompatible."),
936                             option_origin);
937                 if (real_git_dir)
938                         die(_("--bare and --separate-git-dir are incompatible."));
939                 option_no_checkout = 1;
940         }
941
942         if (!option_origin)
943                 option_origin = "origin";
944
945         repo_name = argv[0];
946
947         path = get_repo_path(repo_name, &is_bundle);
948         if (path)
949                 repo = absolute_pathdup(repo_name);
950         else if (!strchr(repo_name, ':'))
951                 die(_("repository '%s' does not exist"), repo_name);
952         else
953                 repo = repo_name;
954
955         /* no need to be strict, transport_set_option() will validate it again */
956         if (option_depth && atoi(option_depth) < 1)
957                 die(_("depth %s is not a positive number"), option_depth);
958
959         if (argc == 2)
960                 dir = xstrdup(argv[1]);
961         else
962                 dir = guess_dir_name(repo_name, is_bundle, option_bare);
963         strip_trailing_slashes(dir);
964
965         dest_exists = dir_exists(dir);
966         if (dest_exists && !is_empty_dir(dir))
967                 die(_("destination path '%s' already exists and is not "
968                         "an empty directory."), dir);
969
970         strbuf_addf(&reflog_msg, "clone: from %s", repo);
971
972         if (option_bare)
973                 work_tree = NULL;
974         else {
975                 work_tree = getenv("GIT_WORK_TREE");
976                 if (work_tree && dir_exists(work_tree))
977                         die(_("working tree '%s' already exists."), work_tree);
978         }
979
980         if (option_bare || work_tree)
981                 git_dir = xstrdup(dir);
982         else {
983                 work_tree = dir;
984                 git_dir = mkpathdup("%s/.git", dir);
985         }
986
987         atexit(remove_junk);
988         sigchain_push_common(remove_junk_on_signal);
989
990         if (!option_bare) {
991                 if (safe_create_leading_directories_const(work_tree) < 0)
992                         die_errno(_("could not create leading directories of '%s'"),
993                                   work_tree);
994                 if (dest_exists)
995                         junk_work_tree_flags |= REMOVE_DIR_KEEP_TOPLEVEL;
996                 else if (mkdir(work_tree, 0777))
997                         die_errno(_("could not create work tree dir '%s'"),
998                                   work_tree);
999                 junk_work_tree = work_tree;
1000                 set_git_work_tree(work_tree);
1001         }
1002
1003         if (real_git_dir) {
1004                 if (dir_exists(real_git_dir))
1005                         junk_git_dir_flags |= REMOVE_DIR_KEEP_TOPLEVEL;
1006                 junk_git_dir = real_git_dir;
1007         } else {
1008                 if (dest_exists)
1009                         junk_git_dir_flags |= REMOVE_DIR_KEEP_TOPLEVEL;
1010                 junk_git_dir = git_dir;
1011         }
1012         if (safe_create_leading_directories_const(git_dir) < 0)
1013                 die(_("could not create leading directories of '%s'"), git_dir);
1014
1015         if (0 <= option_verbosity) {
1016                 if (option_bare)
1017                         fprintf(stderr, _("Cloning into bare repository '%s'...\n"), dir);
1018                 else
1019                         fprintf(stderr, _("Cloning into '%s'...\n"), dir);
1020         }
1021
1022         if (option_recurse_submodules.nr > 0) {
1023                 struct string_list_item *item;
1024                 struct strbuf sb = STRBUF_INIT;
1025
1026                 /* remove duplicates */
1027                 string_list_sort(&option_recurse_submodules);
1028                 string_list_remove_duplicates(&option_recurse_submodules, 0);
1029
1030                 /*
1031                  * NEEDSWORK: In a multi-working-tree world, this needs to be
1032                  * set in the per-worktree config.
1033                  */
1034                 for_each_string_list_item(item, &option_recurse_submodules) {
1035                         strbuf_addf(&sb, "submodule.active=%s",
1036                                     item->string);
1037                         string_list_append(&option_config,
1038                                            strbuf_detach(&sb, NULL));
1039                 }
1040
1041                 if (option_required_reference.nr &&
1042                     option_optional_reference.nr)
1043                         die(_("clone --recursive is not compatible with "
1044                               "both --reference and --reference-if-able"));
1045                 else if (option_required_reference.nr) {
1046                         string_list_append(&option_config,
1047                                 "submodule.alternateLocation=superproject");
1048                         string_list_append(&option_config,
1049                                 "submodule.alternateErrorStrategy=die");
1050                 } else if (option_optional_reference.nr) {
1051                         string_list_append(&option_config,
1052                                 "submodule.alternateLocation=superproject");
1053                         string_list_append(&option_config,
1054                                 "submodule.alternateErrorStrategy=info");
1055                 }
1056         }
1057
1058         init_db(git_dir, real_git_dir, option_template, INIT_DB_QUIET);
1059
1060         if (real_git_dir)
1061                 git_dir = real_git_dir;
1062
1063         write_config(&option_config);
1064
1065         git_config(git_default_config, NULL);
1066
1067         if (option_bare) {
1068                 if (option_mirror)
1069                         src_ref_prefix = "refs/";
1070                 strbuf_addstr(&branch_top, src_ref_prefix);
1071
1072                 git_config_set("core.bare", "true");
1073         } else {
1074                 strbuf_addf(&branch_top, "refs/remotes/%s/", option_origin);
1075         }
1076
1077         strbuf_addf(&key, "remote.%s.url", option_origin);
1078         git_config_set(key.buf, repo);
1079         strbuf_reset(&key);
1080
1081         if (option_no_tags) {
1082                 strbuf_addf(&key, "remote.%s.tagOpt", option_origin);
1083                 git_config_set(key.buf, "--no-tags");
1084                 strbuf_reset(&key);
1085         }
1086
1087         if (option_required_reference.nr || option_optional_reference.nr)
1088                 setup_reference();
1089
1090         remote = remote_get(option_origin);
1091
1092         strbuf_addf(&default_refspec, "+%s*:%s*", src_ref_prefix,
1093                     branch_top.buf);
1094         refspec_append(&remote->fetch, default_refspec.buf);
1095
1096         transport = transport_get(remote, remote->url[0]);
1097         transport_set_verbosity(transport, option_verbosity, option_progress);
1098         transport->family = family;
1099
1100         path = get_repo_path(remote->url[0], &is_bundle);
1101         is_local = option_local != 0 && path && !is_bundle;
1102         if (is_local) {
1103                 if (option_depth)
1104                         warning(_("--depth is ignored in local clones; use file:// instead."));
1105                 if (option_since)
1106                         warning(_("--shallow-since is ignored in local clones; use file:// instead."));
1107                 if (option_not.nr)
1108                         warning(_("--shallow-exclude is ignored in local clones; use file:// instead."));
1109                 if (filter_options.choice)
1110                         warning(_("--filter is ignored in local clones; use file:// instead."));
1111                 if (!access(mkpath("%s/shallow", path), F_OK)) {
1112                         if (option_local > 0)
1113                                 warning(_("source repository is shallow, ignoring --local"));
1114                         is_local = 0;
1115                 }
1116         }
1117         if (option_local > 0 && !is_local)
1118                 warning(_("--local is ignored"));
1119         transport->cloning = 1;
1120
1121         transport_set_option(transport, TRANS_OPT_KEEP, "yes");
1122
1123         if (option_depth)
1124                 transport_set_option(transport, TRANS_OPT_DEPTH,
1125                                      option_depth);
1126         if (option_since)
1127                 transport_set_option(transport, TRANS_OPT_DEEPEN_SINCE,
1128                                      option_since);
1129         if (option_not.nr)
1130                 transport_set_option(transport, TRANS_OPT_DEEPEN_NOT,
1131                                      (const char *)&option_not);
1132         if (option_single_branch)
1133                 transport_set_option(transport, TRANS_OPT_FOLLOWTAGS, "1");
1134
1135         if (option_upload_pack)
1136                 transport_set_option(transport, TRANS_OPT_UPLOADPACK,
1137                                      option_upload_pack);
1138
1139         if (filter_options.choice) {
1140                 struct strbuf expanded_filter_spec = STRBUF_INIT;
1141                 expand_list_objects_filter_spec(&filter_options,
1142                                                 &expanded_filter_spec);
1143                 transport_set_option(transport, TRANS_OPT_LIST_OBJECTS_FILTER,
1144                                      expanded_filter_spec.buf);
1145                 transport_set_option(transport, TRANS_OPT_FROM_PROMISOR, "1");
1146                 strbuf_release(&expanded_filter_spec);
1147         }
1148
1149         if (transport->smart_options && !deepen && !filter_options.choice)
1150                 transport->smart_options->check_self_contained_and_connected = 1;
1151
1152
1153         argv_array_push(&ref_prefixes, "HEAD");
1154         refspec_ref_prefixes(&remote->fetch, &ref_prefixes);
1155         if (option_branch)
1156                 expand_ref_prefix(&ref_prefixes, option_branch);
1157         if (!option_no_tags)
1158                 argv_array_push(&ref_prefixes, "refs/tags/");
1159
1160         refs = transport_get_remote_refs(transport, &ref_prefixes);
1161
1162         if (refs) {
1163                 mapped_refs = wanted_peer_refs(refs, &remote->fetch);
1164                 /*
1165                  * transport_get_remote_refs() may return refs with null sha-1
1166                  * in mapped_refs (see struct transport->get_refs_list
1167                  * comment). In that case we need fetch it early because
1168                  * remote_head code below relies on it.
1169                  *
1170                  * for normal clones, transport_get_remote_refs() should
1171                  * return reliable ref set, we can delay cloning until after
1172                  * remote HEAD check.
1173                  */
1174                 for (ref = refs; ref; ref = ref->next)
1175                         if (is_null_oid(&ref->old_oid)) {
1176                                 complete_refs_before_fetch = 0;
1177                                 break;
1178                         }
1179
1180                 if (!is_local && !complete_refs_before_fetch)
1181                         transport_fetch_refs(transport, mapped_refs);
1182
1183                 remote_head = find_ref_by_name(refs, "HEAD");
1184                 remote_head_points_at =
1185                         guess_remote_head(remote_head, mapped_refs, 0);
1186
1187                 if (option_branch) {
1188                         our_head_points_at =
1189                                 find_remote_branch(mapped_refs, option_branch);
1190
1191                         if (!our_head_points_at)
1192                                 die(_("Remote branch %s not found in upstream %s"),
1193                                     option_branch, option_origin);
1194                 }
1195                 else
1196                         our_head_points_at = remote_head_points_at;
1197         }
1198         else {
1199                 if (option_branch)
1200                         die(_("Remote branch %s not found in upstream %s"),
1201                                         option_branch, option_origin);
1202
1203                 warning(_("You appear to have cloned an empty repository."));
1204                 mapped_refs = NULL;
1205                 our_head_points_at = NULL;
1206                 remote_head_points_at = NULL;
1207                 remote_head = NULL;
1208                 option_no_checkout = 1;
1209                 if (!option_bare)
1210                         install_branch_config(0, "master", option_origin,
1211                                               "refs/heads/master");
1212         }
1213
1214         write_refspec_config(src_ref_prefix, our_head_points_at,
1215                         remote_head_points_at, &branch_top);
1216
1217         if (filter_options.choice)
1218                 partial_clone_register("origin", &filter_options);
1219
1220         if (is_local)
1221                 clone_local(path, git_dir);
1222         else if (refs && complete_refs_before_fetch)
1223                 transport_fetch_refs(transport, mapped_refs);
1224
1225         update_remote_refs(refs, mapped_refs, remote_head_points_at,
1226                            branch_top.buf, reflog_msg.buf, transport,
1227                            !is_local);
1228
1229         update_head(our_head_points_at, remote_head, reflog_msg.buf);
1230
1231         /*
1232          * We want to show progress for recursive submodule clones iff
1233          * we did so for the main clone. But only the transport knows
1234          * the final decision for this flag, so we need to rescue the value
1235          * before we free the transport.
1236          */
1237         submodule_progress = transport->progress;
1238
1239         transport_unlock_pack(transport);
1240         transport_disconnect(transport);
1241
1242         if (option_dissociate) {
1243                 close_all_packs(the_repository->objects);
1244                 dissociate_from_references();
1245         }
1246
1247         junk_mode = JUNK_LEAVE_REPO;
1248         fetch_if_missing = 1;
1249         err = checkout(submodule_progress);
1250
1251         strbuf_release(&reflog_msg);
1252         strbuf_release(&branch_top);
1253         strbuf_release(&key);
1254         strbuf_release(&default_refspec);
1255         junk_mode = JUNK_LEAVE_ALL;
1256
1257         argv_array_clear(&ref_prefixes);
1258         return err;
1259 }