clone: drop dest parameter from copy_alternates()
[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 static struct string_list server_options = STRING_LIST_INIT_NODUP;
70
71 static int recurse_submodules_cb(const struct option *opt,
72                                  const char *arg, int unset)
73 {
74         if (unset)
75                 string_list_clear((struct string_list *)opt->value, 0);
76         else if (arg)
77                 string_list_append((struct string_list *)opt->value, arg);
78         else
79                 string_list_append((struct string_list *)opt->value,
80                                    (const char *)opt->defval);
81
82         return 0;
83 }
84
85 static struct option builtin_clone_options[] = {
86         OPT__VERBOSITY(&option_verbosity),
87         OPT_BOOL(0, "progress", &option_progress,
88                  N_("force progress reporting")),
89         OPT_BOOL('n', "no-checkout", &option_no_checkout,
90                  N_("don't create a checkout")),
91         OPT_BOOL(0, "bare", &option_bare, N_("create a bare repository")),
92         OPT_HIDDEN_BOOL(0, "naked", &option_bare,
93                         N_("create a bare repository")),
94         OPT_BOOL(0, "mirror", &option_mirror,
95                  N_("create a mirror repository (implies bare)")),
96         OPT_BOOL('l', "local", &option_local,
97                 N_("to clone from a local repository")),
98         OPT_BOOL(0, "no-hardlinks", &option_no_hardlinks,
99                     N_("don't use local hardlinks, always copy")),
100         OPT_BOOL('s', "shared", &option_shared,
101                     N_("setup as shared repository")),
102         { OPTION_CALLBACK, 0, "recursive", &option_recurse_submodules,
103           N_("pathspec"), N_("initialize submodules in the clone"),
104           PARSE_OPT_OPTARG | PARSE_OPT_HIDDEN, recurse_submodules_cb,
105           (intptr_t)"." },
106         { OPTION_CALLBACK, 0, "recurse-submodules", &option_recurse_submodules,
107           N_("pathspec"), N_("initialize submodules in the clone"),
108           PARSE_OPT_OPTARG, recurse_submodules_cb, (intptr_t)"." },
109         OPT_INTEGER('j', "jobs", &max_jobs,
110                     N_("number of submodules cloned in parallel")),
111         OPT_STRING(0, "template", &option_template, N_("template-directory"),
112                    N_("directory from which templates will be used")),
113         OPT_STRING_LIST(0, "reference", &option_required_reference, N_("repo"),
114                         N_("reference repository")),
115         OPT_STRING_LIST(0, "reference-if-able", &option_optional_reference,
116                         N_("repo"), N_("reference repository")),
117         OPT_BOOL(0, "dissociate", &option_dissociate,
118                  N_("use --reference only while cloning")),
119         OPT_STRING('o', "origin", &option_origin, N_("name"),
120                    N_("use <name> instead of 'origin' to track upstream")),
121         OPT_STRING('b', "branch", &option_branch, N_("branch"),
122                    N_("checkout <branch> instead of the remote's HEAD")),
123         OPT_STRING('u', "upload-pack", &option_upload_pack, N_("path"),
124                    N_("path to git-upload-pack on the remote")),
125         OPT_STRING(0, "depth", &option_depth, N_("depth"),
126                     N_("create a shallow clone of that depth")),
127         OPT_STRING(0, "shallow-since", &option_since, N_("time"),
128                     N_("create a shallow clone since a specific time")),
129         OPT_STRING_LIST(0, "shallow-exclude", &option_not, N_("revision"),
130                         N_("deepen history of shallow clone, excluding rev")),
131         OPT_BOOL(0, "single-branch", &option_single_branch,
132                     N_("clone only one branch, HEAD or --branch")),
133         OPT_BOOL(0, "no-tags", &option_no_tags,
134                  N_("don't clone any tags, and make later fetches not to follow them")),
135         OPT_BOOL(0, "shallow-submodules", &option_shallow_submodules,
136                     N_("any cloned submodules will be shallow")),
137         OPT_STRING(0, "separate-git-dir", &real_git_dir, N_("gitdir"),
138                    N_("separate git dir from working tree")),
139         OPT_STRING_LIST('c', "config", &option_config, N_("key=value"),
140                         N_("set config inside the new repository")),
141         OPT_STRING_LIST(0, "server-option", &server_options,
142                         N_("server-specific"), N_("option to transmit")),
143         OPT_SET_INT('4', "ipv4", &family, N_("use IPv4 addresses only"),
144                         TRANSPORT_FAMILY_IPV4),
145         OPT_SET_INT('6', "ipv6", &family, N_("use IPv6 addresses only"),
146                         TRANSPORT_FAMILY_IPV6),
147         OPT_PARSE_LIST_OBJECTS_FILTER(&filter_options),
148         OPT_END()
149 };
150
151 static const char *get_repo_path_1(struct strbuf *path, int *is_bundle)
152 {
153         static char *suffix[] = { "/.git", "", ".git/.git", ".git" };
154         static char *bundle_suffix[] = { ".bundle", "" };
155         size_t baselen = path->len;
156         struct stat st;
157         int i;
158
159         for (i = 0; i < ARRAY_SIZE(suffix); i++) {
160                 strbuf_setlen(path, baselen);
161                 strbuf_addstr(path, suffix[i]);
162                 if (stat(path->buf, &st))
163                         continue;
164                 if (S_ISDIR(st.st_mode) && is_git_directory(path->buf)) {
165                         *is_bundle = 0;
166                         return path->buf;
167                 } else if (S_ISREG(st.st_mode) && st.st_size > 8) {
168                         /* Is it a "gitfile"? */
169                         char signature[8];
170                         const char *dst;
171                         int len, fd = open(path->buf, O_RDONLY);
172                         if (fd < 0)
173                                 continue;
174                         len = read_in_full(fd, signature, 8);
175                         close(fd);
176                         if (len != 8 || strncmp(signature, "gitdir: ", 8))
177                                 continue;
178                         dst = read_gitfile(path->buf);
179                         if (dst) {
180                                 *is_bundle = 0;
181                                 return dst;
182                         }
183                 }
184         }
185
186         for (i = 0; i < ARRAY_SIZE(bundle_suffix); i++) {
187                 strbuf_setlen(path, baselen);
188                 strbuf_addstr(path, bundle_suffix[i]);
189                 if (!stat(path->buf, &st) && S_ISREG(st.st_mode)) {
190                         *is_bundle = 1;
191                         return path->buf;
192                 }
193         }
194
195         return NULL;
196 }
197
198 static char *get_repo_path(const char *repo, int *is_bundle)
199 {
200         struct strbuf path = STRBUF_INIT;
201         const char *raw;
202         char *canon;
203
204         strbuf_addstr(&path, repo);
205         raw = get_repo_path_1(&path, is_bundle);
206         canon = raw ? absolute_pathdup(raw) : NULL;
207         strbuf_release(&path);
208         return canon;
209 }
210
211 static char *guess_dir_name(const char *repo, int is_bundle, int is_bare)
212 {
213         const char *end = repo + strlen(repo), *start, *ptr;
214         size_t len;
215         char *dir;
216
217         /*
218          * Skip scheme.
219          */
220         start = strstr(repo, "://");
221         if (start == NULL)
222                 start = repo;
223         else
224                 start += 3;
225
226         /*
227          * Skip authentication data. The stripping does happen
228          * greedily, such that we strip up to the last '@' inside
229          * the host part.
230          */
231         for (ptr = start; ptr < end && !is_dir_sep(*ptr); ptr++) {
232                 if (*ptr == '@')
233                         start = ptr + 1;
234         }
235
236         /*
237          * Strip trailing spaces, slashes and /.git
238          */
239         while (start < end && (is_dir_sep(end[-1]) || isspace(end[-1])))
240                 end--;
241         if (end - start > 5 && is_dir_sep(end[-5]) &&
242             !strncmp(end - 4, ".git", 4)) {
243                 end -= 5;
244                 while (start < end && is_dir_sep(end[-1]))
245                         end--;
246         }
247
248         /*
249          * Strip trailing port number if we've got only a
250          * hostname (that is, there is no dir separator but a
251          * colon). This check is required such that we do not
252          * strip URI's like '/foo/bar:2222.git', which should
253          * result in a dir '2222' being guessed due to backwards
254          * compatibility.
255          */
256         if (memchr(start, '/', end - start) == NULL
257             && memchr(start, ':', end - start) != NULL) {
258                 ptr = end;
259                 while (start < ptr && isdigit(ptr[-1]) && ptr[-1] != ':')
260                         ptr--;
261                 if (start < ptr && ptr[-1] == ':')
262                         end = ptr - 1;
263         }
264
265         /*
266          * Find last component. To remain backwards compatible we
267          * also regard colons as path separators, such that
268          * cloning a repository 'foo:bar.git' would result in a
269          * directory 'bar' being guessed.
270          */
271         ptr = end;
272         while (start < ptr && !is_dir_sep(ptr[-1]) && ptr[-1] != ':')
273                 ptr--;
274         start = ptr;
275
276         /*
277          * Strip .{bundle,git}.
278          */
279         len = end - start;
280         strip_suffix_mem(start, &len, is_bundle ? ".bundle" : ".git");
281
282         if (!len || (len == 1 && *start == '/'))
283                 die(_("No directory name could be guessed.\n"
284                       "Please specify a directory on the command line"));
285
286         if (is_bare)
287                 dir = xstrfmt("%.*s.git", (int)len, start);
288         else
289                 dir = xstrndup(start, len);
290         /*
291          * Replace sequences of 'control' characters and whitespace
292          * with one ascii space, remove leading and trailing spaces.
293          */
294         if (*dir) {
295                 char *out = dir;
296                 int prev_space = 1 /* strip leading whitespace */;
297                 for (end = dir; *end; ++end) {
298                         char ch = *end;
299                         if ((unsigned char)ch < '\x20')
300                                 ch = '\x20';
301                         if (isspace(ch)) {
302                                 if (prev_space)
303                                         continue;
304                                 prev_space = 1;
305                         } else
306                                 prev_space = 0;
307                         *out++ = ch;
308                 }
309                 *out = '\0';
310                 if (out > dir && prev_space)
311                         out[-1] = '\0';
312         }
313         return dir;
314 }
315
316 static void strip_trailing_slashes(char *dir)
317 {
318         char *end = dir + strlen(dir);
319
320         while (dir < end - 1 && is_dir_sep(end[-1]))
321                 end--;
322         *end = '\0';
323 }
324
325 static int add_one_reference(struct string_list_item *item, void *cb_data)
326 {
327         struct strbuf err = STRBUF_INIT;
328         int *required = cb_data;
329         char *ref_git = compute_alternate_path(item->string, &err);
330
331         if (!ref_git) {
332                 if (*required)
333                         die("%s", err.buf);
334                 else
335                         fprintf(stderr,
336                                 _("info: Could not add alternate for '%s': %s\n"),
337                                 item->string, err.buf);
338         } else {
339                 struct strbuf sb = STRBUF_INIT;
340                 strbuf_addf(&sb, "%s/objects", ref_git);
341                 add_to_alternates_file(sb.buf);
342                 strbuf_release(&sb);
343         }
344
345         strbuf_release(&err);
346         free(ref_git);
347         return 0;
348 }
349
350 static void setup_reference(void)
351 {
352         int required = 1;
353         for_each_string_list(&option_required_reference,
354                              add_one_reference, &required);
355         required = 0;
356         for_each_string_list(&option_optional_reference,
357                              add_one_reference, &required);
358 }
359
360 static void copy_alternates(struct strbuf *src, const char *src_repo)
361 {
362         /*
363          * Read from the source objects/info/alternates file
364          * and copy the entries to corresponding file in the
365          * destination repository with add_to_alternates_file().
366          * Both src and dst have "$path/objects/info/alternates".
367          *
368          * Instead of copying bit-for-bit from the original,
369          * we need to append to existing one so that the already
370          * created entry via "clone -s" is not lost, and also
371          * to turn entries with paths relative to the original
372          * absolute, so that they can be used in the new repository.
373          */
374         FILE *in = xfopen(src->buf, "r");
375         struct strbuf line = STRBUF_INIT;
376
377         while (strbuf_getline(&line, in) != EOF) {
378                 char *abs_path;
379                 if (!line.len || line.buf[0] == '#')
380                         continue;
381                 if (is_absolute_path(line.buf)) {
382                         add_to_alternates_file(line.buf);
383                         continue;
384                 }
385                 abs_path = mkpathdup("%s/objects/%s", src_repo, line.buf);
386                 if (!normalize_path_copy(abs_path, abs_path))
387                         add_to_alternates_file(abs_path);
388                 else
389                         warning("skipping invalid relative alternate: %s/%s",
390                                 src_repo, line.buf);
391                 free(abs_path);
392         }
393         strbuf_release(&line);
394         fclose(in);
395 }
396
397 static void copy_or_link_directory(struct strbuf *src, struct strbuf *dest,
398                                    const char *src_repo, int src_baselen)
399 {
400         struct dirent *de;
401         struct stat buf;
402         int src_len, dest_len;
403         DIR *dir;
404
405         dir = opendir(src->buf);
406         if (!dir)
407                 die_errno(_("failed to open '%s'"), src->buf);
408
409         if (mkdir(dest->buf, 0777)) {
410                 if (errno != EEXIST)
411                         die_errno(_("failed to create directory '%s'"), dest->buf);
412                 else if (stat(dest->buf, &buf))
413                         die_errno(_("failed to stat '%s'"), dest->buf);
414                 else if (!S_ISDIR(buf.st_mode))
415                         die(_("%s exists and is not a directory"), dest->buf);
416         }
417
418         strbuf_addch(src, '/');
419         src_len = src->len;
420         strbuf_addch(dest, '/');
421         dest_len = dest->len;
422
423         while ((de = readdir(dir)) != NULL) {
424                 strbuf_setlen(src, src_len);
425                 strbuf_addstr(src, de->d_name);
426                 strbuf_setlen(dest, dest_len);
427                 strbuf_addstr(dest, de->d_name);
428                 if (stat(src->buf, &buf)) {
429                         warning (_("failed to stat %s\n"), src->buf);
430                         continue;
431                 }
432                 if (S_ISDIR(buf.st_mode)) {
433                         if (de->d_name[0] != '.')
434                                 copy_or_link_directory(src, dest,
435                                                        src_repo, src_baselen);
436                         continue;
437                 }
438
439                 /* Files that cannot be copied bit-for-bit... */
440                 if (!strcmp(src->buf + src_baselen, "/info/alternates")) {
441                         copy_alternates(src, src_repo);
442                         continue;
443                 }
444
445                 if (unlink(dest->buf) && errno != ENOENT)
446                         die_errno(_("failed to unlink '%s'"), dest->buf);
447                 if (!option_no_hardlinks) {
448                         if (!link(src->buf, dest->buf))
449                                 continue;
450                         if (option_local > 0)
451                                 die_errno(_("failed to create link '%s'"), dest->buf);
452                         option_no_hardlinks = 1;
453                 }
454                 if (copy_file_with_time(dest->buf, src->buf, 0666))
455                         die_errno(_("failed to copy file to '%s'"), dest->buf);
456         }
457         closedir(dir);
458 }
459
460 static void clone_local(const char *src_repo, const char *dest_repo)
461 {
462         if (option_shared) {
463                 struct strbuf alt = STRBUF_INIT;
464                 get_common_dir(&alt, src_repo);
465                 strbuf_addstr(&alt, "/objects");
466                 add_to_alternates_file(alt.buf);
467                 strbuf_release(&alt);
468         } else {
469                 struct strbuf src = STRBUF_INIT;
470                 struct strbuf dest = STRBUF_INIT;
471                 get_common_dir(&src, src_repo);
472                 get_common_dir(&dest, dest_repo);
473                 strbuf_addstr(&src, "/objects");
474                 strbuf_addstr(&dest, "/objects");
475                 copy_or_link_directory(&src, &dest, src_repo, src.len);
476                 strbuf_release(&src);
477                 strbuf_release(&dest);
478         }
479
480         if (0 <= option_verbosity)
481                 fprintf(stderr, _("done.\n"));
482 }
483
484 static const char *junk_work_tree;
485 static int junk_work_tree_flags;
486 static const char *junk_git_dir;
487 static int junk_git_dir_flags;
488 static enum {
489         JUNK_LEAVE_NONE,
490         JUNK_LEAVE_REPO,
491         JUNK_LEAVE_ALL
492 } junk_mode = JUNK_LEAVE_NONE;
493
494 static const char junk_leave_repo_msg[] =
495 N_("Clone succeeded, but checkout failed.\n"
496    "You can inspect what was checked out with 'git status'\n"
497    "and retry the checkout with 'git checkout -f HEAD'\n");
498
499 static void remove_junk(void)
500 {
501         struct strbuf sb = STRBUF_INIT;
502
503         switch (junk_mode) {
504         case JUNK_LEAVE_REPO:
505                 warning("%s", _(junk_leave_repo_msg));
506                 /* fall-through */
507         case JUNK_LEAVE_ALL:
508                 return;
509         default:
510                 /* proceed to removal */
511                 break;
512         }
513
514         if (junk_git_dir) {
515                 strbuf_addstr(&sb, junk_git_dir);
516                 remove_dir_recursively(&sb, junk_git_dir_flags);
517                 strbuf_reset(&sb);
518         }
519         if (junk_work_tree) {
520                 strbuf_addstr(&sb, junk_work_tree);
521                 remove_dir_recursively(&sb, junk_work_tree_flags);
522         }
523         strbuf_release(&sb);
524 }
525
526 static void remove_junk_on_signal(int signo)
527 {
528         remove_junk();
529         sigchain_pop(signo);
530         raise(signo);
531 }
532
533 static struct ref *find_remote_branch(const struct ref *refs, const char *branch)
534 {
535         struct ref *ref;
536         struct strbuf head = STRBUF_INIT;
537         strbuf_addstr(&head, "refs/heads/");
538         strbuf_addstr(&head, branch);
539         ref = find_ref_by_name(refs, head.buf);
540         strbuf_release(&head);
541
542         if (ref)
543                 return ref;
544
545         strbuf_addstr(&head, "refs/tags/");
546         strbuf_addstr(&head, branch);
547         ref = find_ref_by_name(refs, head.buf);
548         strbuf_release(&head);
549
550         return ref;
551 }
552
553 static struct ref *wanted_peer_refs(const struct ref *refs,
554                 struct refspec *refspec)
555 {
556         struct ref *head = copy_ref(find_ref_by_name(refs, "HEAD"));
557         struct ref *local_refs = head;
558         struct ref **tail = head ? &head->next : &local_refs;
559
560         if (option_single_branch) {
561                 struct ref *remote_head = NULL;
562
563                 if (!option_branch)
564                         remote_head = guess_remote_head(head, refs, 0);
565                 else {
566                         local_refs = NULL;
567                         tail = &local_refs;
568                         remote_head = copy_ref(find_remote_branch(refs, option_branch));
569                 }
570
571                 if (!remote_head && option_branch)
572                         warning(_("Could not find remote branch %s to clone."),
573                                 option_branch);
574                 else {
575                         int i;
576                         for (i = 0; i < refspec->nr; i++)
577                                 get_fetch_map(remote_head, &refspec->items[i],
578                                               &tail, 0);
579
580                         /* if --branch=tag, pull the requested tag explicitly */
581                         get_fetch_map(remote_head, tag_refspec, &tail, 0);
582                 }
583         } else {
584                 int i;
585                 for (i = 0; i < refspec->nr; i++)
586                         get_fetch_map(refs, &refspec->items[i], &tail, 0);
587         }
588
589         if (!option_mirror && !option_single_branch && !option_no_tags)
590                 get_fetch_map(refs, tag_refspec, &tail, 0);
591
592         return local_refs;
593 }
594
595 static void write_remote_refs(const struct ref *local_refs)
596 {
597         const struct ref *r;
598
599         struct ref_transaction *t;
600         struct strbuf err = STRBUF_INIT;
601
602         t = ref_transaction_begin(&err);
603         if (!t)
604                 die("%s", err.buf);
605
606         for (r = local_refs; r; r = r->next) {
607                 if (!r->peer_ref)
608                         continue;
609                 if (ref_transaction_create(t, r->peer_ref->name, &r->old_oid,
610                                            0, NULL, &err))
611                         die("%s", err.buf);
612         }
613
614         if (initial_ref_transaction_commit(t, &err))
615                 die("%s", err.buf);
616
617         strbuf_release(&err);
618         ref_transaction_free(t);
619 }
620
621 static void write_followtags(const struct ref *refs, const char *msg)
622 {
623         const struct ref *ref;
624         for (ref = refs; ref; ref = ref->next) {
625                 if (!starts_with(ref->name, "refs/tags/"))
626                         continue;
627                 if (ends_with(ref->name, "^{}"))
628                         continue;
629                 if (!has_object_file(&ref->old_oid))
630                         continue;
631                 update_ref(msg, ref->name, &ref->old_oid, NULL, 0,
632                            UPDATE_REFS_DIE_ON_ERR);
633         }
634 }
635
636 static int iterate_ref_map(void *cb_data, struct object_id *oid)
637 {
638         struct ref **rm = cb_data;
639         struct ref *ref = *rm;
640
641         /*
642          * Skip anything missing a peer_ref, which we are not
643          * actually going to write a ref for.
644          */
645         while (ref && !ref->peer_ref)
646                 ref = ref->next;
647         /* Returning -1 notes "end of list" to the caller. */
648         if (!ref)
649                 return -1;
650
651         oidcpy(oid, &ref->old_oid);
652         *rm = ref->next;
653         return 0;
654 }
655
656 static void update_remote_refs(const struct ref *refs,
657                                const struct ref *mapped_refs,
658                                const struct ref *remote_head_points_at,
659                                const char *branch_top,
660                                const char *msg,
661                                struct transport *transport,
662                                int check_connectivity)
663 {
664         const struct ref *rm = mapped_refs;
665
666         if (check_connectivity) {
667                 struct check_connected_options opt = CHECK_CONNECTED_INIT;
668
669                 opt.transport = transport;
670                 opt.progress = transport->progress;
671
672                 if (check_connected(iterate_ref_map, &rm, &opt))
673                         die(_("remote did not send all necessary objects"));
674         }
675
676         if (refs) {
677                 write_remote_refs(mapped_refs);
678                 if (option_single_branch && !option_no_tags)
679                         write_followtags(refs, msg);
680         }
681
682         if (remote_head_points_at && !option_bare) {
683                 struct strbuf head_ref = STRBUF_INIT;
684                 strbuf_addstr(&head_ref, branch_top);
685                 strbuf_addstr(&head_ref, "HEAD");
686                 if (create_symref(head_ref.buf,
687                                   remote_head_points_at->peer_ref->name,
688                                   msg) < 0)
689                         die(_("unable to update %s"), head_ref.buf);
690                 strbuf_release(&head_ref);
691         }
692 }
693
694 static void update_head(const struct ref *our, const struct ref *remote,
695                         const char *msg)
696 {
697         const char *head;
698         if (our && skip_prefix(our->name, "refs/heads/", &head)) {
699                 /* Local default branch link */
700                 if (create_symref("HEAD", our->name, NULL) < 0)
701                         die(_("unable to update HEAD"));
702                 if (!option_bare) {
703                         update_ref(msg, "HEAD", &our->old_oid, NULL, 0,
704                                    UPDATE_REFS_DIE_ON_ERR);
705                         install_branch_config(0, head, option_origin, our->name);
706                 }
707         } else if (our) {
708                 struct commit *c = lookup_commit_reference(the_repository,
709                                                            &our->old_oid);
710                 /* --branch specifies a non-branch (i.e. tags), detach HEAD */
711                 update_ref(msg, "HEAD", &c->object.oid, NULL, REF_NO_DEREF,
712                            UPDATE_REFS_DIE_ON_ERR);
713         } else if (remote) {
714                 /*
715                  * We know remote HEAD points to a non-branch, or
716                  * HEAD points to a branch but we don't know which one.
717                  * Detach HEAD in all these cases.
718                  */
719                 update_ref(msg, "HEAD", &remote->old_oid, NULL, REF_NO_DEREF,
720                            UPDATE_REFS_DIE_ON_ERR);
721         }
722 }
723
724 static int checkout(int submodule_progress)
725 {
726         struct object_id oid;
727         char *head;
728         struct lock_file lock_file = LOCK_INIT;
729         struct unpack_trees_options opts;
730         struct tree *tree;
731         struct tree_desc t;
732         int err = 0;
733
734         if (option_no_checkout)
735                 return 0;
736
737         head = resolve_refdup("HEAD", RESOLVE_REF_READING, &oid, NULL);
738         if (!head) {
739                 warning(_("remote HEAD refers to nonexistent ref, "
740                           "unable to checkout.\n"));
741                 return 0;
742         }
743         if (!strcmp(head, "HEAD")) {
744                 if (advice_detached_head)
745                         detach_advice(oid_to_hex(&oid));
746         } else {
747                 if (!starts_with(head, "refs/heads/"))
748                         die(_("HEAD not found below refs/heads!"));
749         }
750         free(head);
751
752         /* We need to be in the new work tree for the checkout */
753         setup_work_tree();
754
755         hold_locked_index(&lock_file, LOCK_DIE_ON_ERROR);
756
757         memset(&opts, 0, sizeof opts);
758         opts.update = 1;
759         opts.merge = 1;
760         opts.clone = 1;
761         opts.fn = oneway_merge;
762         opts.verbose_update = (option_verbosity >= 0);
763         opts.src_index = &the_index;
764         opts.dst_index = &the_index;
765
766         tree = parse_tree_indirect(&oid);
767         parse_tree(tree);
768         init_tree_desc(&t, tree->buffer, tree->size);
769         if (unpack_trees(1, &t, &opts) < 0)
770                 die(_("unable to checkout working tree"));
771
772         if (write_locked_index(&the_index, &lock_file, COMMIT_LOCK))
773                 die(_("unable to write new index file"));
774
775         err |= run_hook_le(NULL, "post-checkout", sha1_to_hex(null_sha1),
776                            oid_to_hex(&oid), "1", NULL);
777
778         if (!err && (option_recurse_submodules.nr > 0)) {
779                 struct argv_array args = ARGV_ARRAY_INIT;
780                 argv_array_pushl(&args, "submodule", "update", "--init", "--recursive", NULL);
781
782                 if (option_shallow_submodules == 1)
783                         argv_array_push(&args, "--depth=1");
784
785                 if (max_jobs != -1)
786                         argv_array_pushf(&args, "--jobs=%d", max_jobs);
787
788                 if (submodule_progress)
789                         argv_array_push(&args, "--progress");
790
791                 if (option_verbosity < 0)
792                         argv_array_push(&args, "--quiet");
793
794                 err = run_command_v_opt(args.argv, RUN_GIT_CMD);
795                 argv_array_clear(&args);
796         }
797
798         return err;
799 }
800
801 static int write_one_config(const char *key, const char *value, void *data)
802 {
803         return git_config_set_multivar_gently(key,
804                                               value ? value : "true",
805                                               CONFIG_REGEX_NONE, 0);
806 }
807
808 static void write_config(struct string_list *config)
809 {
810         int i;
811
812         for (i = 0; i < config->nr; i++) {
813                 if (git_config_parse_parameter(config->items[i].string,
814                                                write_one_config, NULL) < 0)
815                         die(_("unable to write parameters to config file"));
816         }
817 }
818
819 static void write_refspec_config(const char *src_ref_prefix,
820                 const struct ref *our_head_points_at,
821                 const struct ref *remote_head_points_at,
822                 struct strbuf *branch_top)
823 {
824         struct strbuf key = STRBUF_INIT;
825         struct strbuf value = STRBUF_INIT;
826
827         if (option_mirror || !option_bare) {
828                 if (option_single_branch && !option_mirror) {
829                         if (option_branch) {
830                                 if (starts_with(our_head_points_at->name, "refs/tags/"))
831                                         strbuf_addf(&value, "+%s:%s", our_head_points_at->name,
832                                                 our_head_points_at->name);
833                                 else
834                                         strbuf_addf(&value, "+%s:%s%s", our_head_points_at->name,
835                                                 branch_top->buf, option_branch);
836                         } else if (remote_head_points_at) {
837                                 const char *head = remote_head_points_at->name;
838                                 if (!skip_prefix(head, "refs/heads/", &head))
839                                         BUG("remote HEAD points at non-head?");
840
841                                 strbuf_addf(&value, "+%s:%s%s", remote_head_points_at->name,
842                                                 branch_top->buf, head);
843                         }
844                         /*
845                          * otherwise, the next "git fetch" will
846                          * simply fetch from HEAD without updating
847                          * any remote-tracking branch, which is what
848                          * we want.
849                          */
850                 } else {
851                         strbuf_addf(&value, "+%s*:%s*", src_ref_prefix, branch_top->buf);
852                 }
853                 /* Configure the remote */
854                 if (value.len) {
855                         strbuf_addf(&key, "remote.%s.fetch", option_origin);
856                         git_config_set_multivar(key.buf, value.buf, "^$", 0);
857                         strbuf_reset(&key);
858
859                         if (option_mirror) {
860                                 strbuf_addf(&key, "remote.%s.mirror", option_origin);
861                                 git_config_set(key.buf, "true");
862                                 strbuf_reset(&key);
863                         }
864                 }
865         }
866
867         strbuf_release(&key);
868         strbuf_release(&value);
869 }
870
871 static void dissociate_from_references(void)
872 {
873         static const char* argv[] = { "repack", "-a", "-d", NULL };
874         char *alternates = git_pathdup("objects/info/alternates");
875
876         if (!access(alternates, F_OK)) {
877                 if (run_command_v_opt(argv, RUN_GIT_CMD|RUN_COMMAND_NO_STDIN))
878                         die(_("cannot repack to clean up"));
879                 if (unlink(alternates) && errno != ENOENT)
880                         die_errno(_("cannot unlink temporary alternates file"));
881         }
882         free(alternates);
883 }
884
885 static int dir_exists(const char *path)
886 {
887         struct stat sb;
888         return !stat(path, &sb);
889 }
890
891 int cmd_clone(int argc, const char **argv, const char *prefix)
892 {
893         int is_bundle = 0, is_local;
894         const char *repo_name, *repo, *work_tree, *git_dir;
895         char *path, *dir;
896         int dest_exists;
897         const struct ref *refs, *remote_head;
898         const struct ref *remote_head_points_at;
899         const struct ref *our_head_points_at;
900         struct ref *mapped_refs;
901         const struct ref *ref;
902         struct strbuf key = STRBUF_INIT;
903         struct strbuf default_refspec = STRBUF_INIT;
904         struct strbuf branch_top = STRBUF_INIT, reflog_msg = STRBUF_INIT;
905         struct transport *transport = NULL;
906         const char *src_ref_prefix = "refs/heads/";
907         struct remote *remote;
908         int err = 0, complete_refs_before_fetch = 1;
909         int submodule_progress;
910
911         struct argv_array ref_prefixes = ARGV_ARRAY_INIT;
912
913         fetch_if_missing = 0;
914
915         packet_trace_identity("clone");
916         argc = parse_options(argc, argv, prefix, builtin_clone_options,
917                              builtin_clone_usage, 0);
918
919         if (argc > 2)
920                 usage_msg_opt(_("Too many arguments."),
921                         builtin_clone_usage, builtin_clone_options);
922
923         if (argc == 0)
924                 usage_msg_opt(_("You must specify a repository to clone."),
925                         builtin_clone_usage, builtin_clone_options);
926
927         if (option_depth || option_since || option_not.nr)
928                 deepen = 1;
929         if (option_single_branch == -1)
930                 option_single_branch = deepen ? 1 : 0;
931
932         if (option_mirror)
933                 option_bare = 1;
934
935         if (option_bare) {
936                 if (option_origin)
937                         die(_("--bare and --origin %s options are incompatible."),
938                             option_origin);
939                 if (real_git_dir)
940                         die(_("--bare and --separate-git-dir are incompatible."));
941                 option_no_checkout = 1;
942         }
943
944         if (!option_origin)
945                 option_origin = "origin";
946
947         repo_name = argv[0];
948
949         path = get_repo_path(repo_name, &is_bundle);
950         if (path)
951                 repo = absolute_pathdup(repo_name);
952         else if (!strchr(repo_name, ':'))
953                 die(_("repository '%s' does not exist"), repo_name);
954         else
955                 repo = repo_name;
956
957         /* no need to be strict, transport_set_option() will validate it again */
958         if (option_depth && atoi(option_depth) < 1)
959                 die(_("depth %s is not a positive number"), option_depth);
960
961         if (argc == 2)
962                 dir = xstrdup(argv[1]);
963         else
964                 dir = guess_dir_name(repo_name, is_bundle, option_bare);
965         strip_trailing_slashes(dir);
966
967         dest_exists = dir_exists(dir);
968         if (dest_exists && !is_empty_dir(dir))
969                 die(_("destination path '%s' already exists and is not "
970                         "an empty directory."), dir);
971
972         strbuf_addf(&reflog_msg, "clone: from %s", repo);
973
974         if (option_bare)
975                 work_tree = NULL;
976         else {
977                 work_tree = getenv("GIT_WORK_TREE");
978                 if (work_tree && dir_exists(work_tree))
979                         die(_("working tree '%s' already exists."), work_tree);
980         }
981
982         if (option_bare || work_tree)
983                 git_dir = xstrdup(dir);
984         else {
985                 work_tree = dir;
986                 git_dir = mkpathdup("%s/.git", dir);
987         }
988
989         atexit(remove_junk);
990         sigchain_push_common(remove_junk_on_signal);
991
992         if (!option_bare) {
993                 if (safe_create_leading_directories_const(work_tree) < 0)
994                         die_errno(_("could not create leading directories of '%s'"),
995                                   work_tree);
996                 if (dest_exists)
997                         junk_work_tree_flags |= REMOVE_DIR_KEEP_TOPLEVEL;
998                 else if (mkdir(work_tree, 0777))
999                         die_errno(_("could not create work tree dir '%s'"),
1000                                   work_tree);
1001                 junk_work_tree = work_tree;
1002                 set_git_work_tree(work_tree);
1003         }
1004
1005         if (real_git_dir) {
1006                 if (dir_exists(real_git_dir))
1007                         junk_git_dir_flags |= REMOVE_DIR_KEEP_TOPLEVEL;
1008                 junk_git_dir = real_git_dir;
1009         } else {
1010                 if (dest_exists)
1011                         junk_git_dir_flags |= REMOVE_DIR_KEEP_TOPLEVEL;
1012                 junk_git_dir = git_dir;
1013         }
1014         if (safe_create_leading_directories_const(git_dir) < 0)
1015                 die(_("could not create leading directories of '%s'"), git_dir);
1016
1017         if (0 <= option_verbosity) {
1018                 if (option_bare)
1019                         fprintf(stderr, _("Cloning into bare repository '%s'...\n"), dir);
1020                 else
1021                         fprintf(stderr, _("Cloning into '%s'...\n"), dir);
1022         }
1023
1024         if (option_recurse_submodules.nr > 0) {
1025                 struct string_list_item *item;
1026                 struct strbuf sb = STRBUF_INIT;
1027
1028                 /* remove duplicates */
1029                 string_list_sort(&option_recurse_submodules);
1030                 string_list_remove_duplicates(&option_recurse_submodules, 0);
1031
1032                 /*
1033                  * NEEDSWORK: In a multi-working-tree world, this needs to be
1034                  * set in the per-worktree config.
1035                  */
1036                 for_each_string_list_item(item, &option_recurse_submodules) {
1037                         strbuf_addf(&sb, "submodule.active=%s",
1038                                     item->string);
1039                         string_list_append(&option_config,
1040                                            strbuf_detach(&sb, NULL));
1041                 }
1042
1043                 if (option_required_reference.nr &&
1044                     option_optional_reference.nr)
1045                         die(_("clone --recursive is not compatible with "
1046                               "both --reference and --reference-if-able"));
1047                 else if (option_required_reference.nr) {
1048                         string_list_append(&option_config,
1049                                 "submodule.alternateLocation=superproject");
1050                         string_list_append(&option_config,
1051                                 "submodule.alternateErrorStrategy=die");
1052                 } else if (option_optional_reference.nr) {
1053                         string_list_append(&option_config,
1054                                 "submodule.alternateLocation=superproject");
1055                         string_list_append(&option_config,
1056                                 "submodule.alternateErrorStrategy=info");
1057                 }
1058         }
1059
1060         init_db(git_dir, real_git_dir, option_template, INIT_DB_QUIET);
1061
1062         if (real_git_dir)
1063                 git_dir = real_git_dir;
1064
1065         write_config(&option_config);
1066
1067         git_config(git_default_config, NULL);
1068
1069         if (option_bare) {
1070                 if (option_mirror)
1071                         src_ref_prefix = "refs/";
1072                 strbuf_addstr(&branch_top, src_ref_prefix);
1073
1074                 git_config_set("core.bare", "true");
1075         } else {
1076                 strbuf_addf(&branch_top, "refs/remotes/%s/", option_origin);
1077         }
1078
1079         strbuf_addf(&key, "remote.%s.url", option_origin);
1080         git_config_set(key.buf, repo);
1081         strbuf_reset(&key);
1082
1083         if (option_no_tags) {
1084                 strbuf_addf(&key, "remote.%s.tagOpt", option_origin);
1085                 git_config_set(key.buf, "--no-tags");
1086                 strbuf_reset(&key);
1087         }
1088
1089         if (option_required_reference.nr || option_optional_reference.nr)
1090                 setup_reference();
1091
1092         remote = remote_get(option_origin);
1093
1094         strbuf_addf(&default_refspec, "+%s*:%s*", src_ref_prefix,
1095                     branch_top.buf);
1096         refspec_append(&remote->fetch, default_refspec.buf);
1097
1098         transport = transport_get(remote, remote->url[0]);
1099         transport_set_verbosity(transport, option_verbosity, option_progress);
1100         transport->family = family;
1101
1102         path = get_repo_path(remote->url[0], &is_bundle);
1103         is_local = option_local != 0 && path && !is_bundle;
1104         if (is_local) {
1105                 if (option_depth)
1106                         warning(_("--depth is ignored in local clones; use file:// instead."));
1107                 if (option_since)
1108                         warning(_("--shallow-since is ignored in local clones; use file:// instead."));
1109                 if (option_not.nr)
1110                         warning(_("--shallow-exclude is ignored in local clones; use file:// instead."));
1111                 if (filter_options.choice)
1112                         warning(_("--filter is ignored in local clones; use file:// instead."));
1113                 if (!access(mkpath("%s/shallow", path), F_OK)) {
1114                         if (option_local > 0)
1115                                 warning(_("source repository is shallow, ignoring --local"));
1116                         is_local = 0;
1117                 }
1118         }
1119         if (option_local > 0 && !is_local)
1120                 warning(_("--local is ignored"));
1121         transport->cloning = 1;
1122
1123         transport_set_option(transport, TRANS_OPT_KEEP, "yes");
1124
1125         if (option_depth)
1126                 transport_set_option(transport, TRANS_OPT_DEPTH,
1127                                      option_depth);
1128         if (option_since)
1129                 transport_set_option(transport, TRANS_OPT_DEEPEN_SINCE,
1130                                      option_since);
1131         if (option_not.nr)
1132                 transport_set_option(transport, TRANS_OPT_DEEPEN_NOT,
1133                                      (const char *)&option_not);
1134         if (option_single_branch)
1135                 transport_set_option(transport, TRANS_OPT_FOLLOWTAGS, "1");
1136
1137         if (option_upload_pack)
1138                 transport_set_option(transport, TRANS_OPT_UPLOADPACK,
1139                                      option_upload_pack);
1140
1141         if (server_options.nr)
1142                 transport->server_options = &server_options;
1143
1144         if (filter_options.choice) {
1145                 struct strbuf expanded_filter_spec = STRBUF_INIT;
1146                 expand_list_objects_filter_spec(&filter_options,
1147                                                 &expanded_filter_spec);
1148                 transport_set_option(transport, TRANS_OPT_LIST_OBJECTS_FILTER,
1149                                      expanded_filter_spec.buf);
1150                 transport_set_option(transport, TRANS_OPT_FROM_PROMISOR, "1");
1151                 strbuf_release(&expanded_filter_spec);
1152         }
1153
1154         if (transport->smart_options && !deepen && !filter_options.choice)
1155                 transport->smart_options->check_self_contained_and_connected = 1;
1156
1157
1158         argv_array_push(&ref_prefixes, "HEAD");
1159         refspec_ref_prefixes(&remote->fetch, &ref_prefixes);
1160         if (option_branch)
1161                 expand_ref_prefix(&ref_prefixes, option_branch);
1162         if (!option_no_tags)
1163                 argv_array_push(&ref_prefixes, "refs/tags/");
1164
1165         refs = transport_get_remote_refs(transport, &ref_prefixes);
1166
1167         if (refs) {
1168                 mapped_refs = wanted_peer_refs(refs, &remote->fetch);
1169                 /*
1170                  * transport_get_remote_refs() may return refs with null sha-1
1171                  * in mapped_refs (see struct transport->get_refs_list
1172                  * comment). In that case we need fetch it early because
1173                  * remote_head code below relies on it.
1174                  *
1175                  * for normal clones, transport_get_remote_refs() should
1176                  * return reliable ref set, we can delay cloning until after
1177                  * remote HEAD check.
1178                  */
1179                 for (ref = refs; ref; ref = ref->next)
1180                         if (is_null_oid(&ref->old_oid)) {
1181                                 complete_refs_before_fetch = 0;
1182                                 break;
1183                         }
1184
1185                 if (!is_local && !complete_refs_before_fetch)
1186                         transport_fetch_refs(transport, mapped_refs);
1187
1188                 remote_head = find_ref_by_name(refs, "HEAD");
1189                 remote_head_points_at =
1190                         guess_remote_head(remote_head, mapped_refs, 0);
1191
1192                 if (option_branch) {
1193                         our_head_points_at =
1194                                 find_remote_branch(mapped_refs, option_branch);
1195
1196                         if (!our_head_points_at)
1197                                 die(_("Remote branch %s not found in upstream %s"),
1198                                     option_branch, option_origin);
1199                 }
1200                 else
1201                         our_head_points_at = remote_head_points_at;
1202         }
1203         else {
1204                 if (option_branch)
1205                         die(_("Remote branch %s not found in upstream %s"),
1206                                         option_branch, option_origin);
1207
1208                 warning(_("You appear to have cloned an empty repository."));
1209                 mapped_refs = NULL;
1210                 our_head_points_at = NULL;
1211                 remote_head_points_at = NULL;
1212                 remote_head = NULL;
1213                 option_no_checkout = 1;
1214                 if (!option_bare)
1215                         install_branch_config(0, "master", option_origin,
1216                                               "refs/heads/master");
1217         }
1218
1219         write_refspec_config(src_ref_prefix, our_head_points_at,
1220                         remote_head_points_at, &branch_top);
1221
1222         if (filter_options.choice)
1223                 partial_clone_register("origin", &filter_options);
1224
1225         if (is_local)
1226                 clone_local(path, git_dir);
1227         else if (refs && complete_refs_before_fetch)
1228                 transport_fetch_refs(transport, mapped_refs);
1229
1230         update_remote_refs(refs, mapped_refs, remote_head_points_at,
1231                            branch_top.buf, reflog_msg.buf, transport,
1232                            !is_local);
1233
1234         update_head(our_head_points_at, remote_head, reflog_msg.buf);
1235
1236         /*
1237          * We want to show progress for recursive submodule clones iff
1238          * we did so for the main clone. But only the transport knows
1239          * the final decision for this flag, so we need to rescue the value
1240          * before we free the transport.
1241          */
1242         submodule_progress = transport->progress;
1243
1244         transport_unlock_pack(transport);
1245         transport_disconnect(transport);
1246
1247         if (option_dissociate) {
1248                 close_all_packs(the_repository->objects);
1249                 dissociate_from_references();
1250         }
1251
1252         junk_mode = JUNK_LEAVE_REPO;
1253         fetch_if_missing = 1;
1254         err = checkout(submodule_progress);
1255
1256         strbuf_release(&reflog_msg);
1257         strbuf_release(&branch_top);
1258         strbuf_release(&key);
1259         strbuf_release(&default_refspec);
1260         junk_mode = JUNK_LEAVE_ALL;
1261
1262         argv_array_clear(&ref_prefixes);
1263         return err;
1264 }