Merge branch 'bw/realpath-wo-chdir'
[git] / builtin / submodule--helper.c
1 #include "builtin.h"
2 #include "cache.h"
3 #include "parse-options.h"
4 #include "quote.h"
5 #include "pathspec.h"
6 #include "dir.h"
7 #include "utf8.h"
8 #include "submodule.h"
9 #include "submodule-config.h"
10 #include "string-list.h"
11 #include "run-command.h"
12 #include "remote.h"
13 #include "refs.h"
14 #include "connect.h"
15
16 static char *get_default_remote(void)
17 {
18         char *dest = NULL, *ret;
19         unsigned char sha1[20];
20         struct strbuf sb = STRBUF_INIT;
21         const char *refname = resolve_ref_unsafe("HEAD", 0, sha1, NULL);
22
23         if (!refname)
24                 die(_("No such ref: %s"), "HEAD");
25
26         /* detached HEAD */
27         if (!strcmp(refname, "HEAD"))
28                 return xstrdup("origin");
29
30         if (!skip_prefix(refname, "refs/heads/", &refname))
31                 die(_("Expecting a full ref name, got %s"), refname);
32
33         strbuf_addf(&sb, "branch.%s.remote", refname);
34         if (git_config_get_string(sb.buf, &dest))
35                 ret = xstrdup("origin");
36         else
37                 ret = dest;
38
39         strbuf_release(&sb);
40         return ret;
41 }
42
43 static int starts_with_dot_slash(const char *str)
44 {
45         return str[0] == '.' && is_dir_sep(str[1]);
46 }
47
48 static int starts_with_dot_dot_slash(const char *str)
49 {
50         return str[0] == '.' && str[1] == '.' && is_dir_sep(str[2]);
51 }
52
53 /*
54  * Returns 1 if it was the last chop before ':'.
55  */
56 static int chop_last_dir(char **remoteurl, int is_relative)
57 {
58         char *rfind = find_last_dir_sep(*remoteurl);
59         if (rfind) {
60                 *rfind = '\0';
61                 return 0;
62         }
63
64         rfind = strrchr(*remoteurl, ':');
65         if (rfind) {
66                 *rfind = '\0';
67                 return 1;
68         }
69
70         if (is_relative || !strcmp(".", *remoteurl))
71                 die(_("cannot strip one component off url '%s'"),
72                         *remoteurl);
73
74         free(*remoteurl);
75         *remoteurl = xstrdup(".");
76         return 0;
77 }
78
79 /*
80  * The `url` argument is the URL that navigates to the submodule origin
81  * repo. When relative, this URL is relative to the superproject origin
82  * URL repo. The `up_path` argument, if specified, is the relative
83  * path that navigates from the submodule working tree to the superproject
84  * working tree. Returns the origin URL of the submodule.
85  *
86  * Return either an absolute URL or filesystem path (if the superproject
87  * origin URL is an absolute URL or filesystem path, respectively) or a
88  * relative file system path (if the superproject origin URL is a relative
89  * file system path).
90  *
91  * When the output is a relative file system path, the path is either
92  * relative to the submodule working tree, if up_path is specified, or to
93  * the superproject working tree otherwise.
94  *
95  * NEEDSWORK: This works incorrectly on the domain and protocol part.
96  * remote_url      url              outcome          expectation
97  * http://a.com/b  ../c             http://a.com/c   as is
98  * http://a.com/b/ ../c             http://a.com/c   same as previous line, but
99  *                                                   ignore trailing slash in url
100  * http://a.com/b  ../../c          http://c         error out
101  * http://a.com/b  ../../../c       http:/c          error out
102  * http://a.com/b  ../../../../c    http:c           error out
103  * http://a.com/b  ../../../../../c    .:c           error out
104  * NEEDSWORK: Given how chop_last_dir() works, this function is broken
105  * when a local part has a colon in its path component, too.
106  */
107 static char *relative_url(const char *remote_url,
108                                 const char *url,
109                                 const char *up_path)
110 {
111         int is_relative = 0;
112         int colonsep = 0;
113         char *out;
114         char *remoteurl = xstrdup(remote_url);
115         struct strbuf sb = STRBUF_INIT;
116         size_t len = strlen(remoteurl);
117
118         if (is_dir_sep(remoteurl[len-1]))
119                 remoteurl[len-1] = '\0';
120
121         if (!url_is_local_not_ssh(remoteurl) || is_absolute_path(remoteurl))
122                 is_relative = 0;
123         else {
124                 is_relative = 1;
125                 /*
126                  * Prepend a './' to ensure all relative
127                  * remoteurls start with './' or '../'
128                  */
129                 if (!starts_with_dot_slash(remoteurl) &&
130                     !starts_with_dot_dot_slash(remoteurl)) {
131                         strbuf_reset(&sb);
132                         strbuf_addf(&sb, "./%s", remoteurl);
133                         free(remoteurl);
134                         remoteurl = strbuf_detach(&sb, NULL);
135                 }
136         }
137         /*
138          * When the url starts with '../', remove that and the
139          * last directory in remoteurl.
140          */
141         while (url) {
142                 if (starts_with_dot_dot_slash(url)) {
143                         url += 3;
144                         colonsep |= chop_last_dir(&remoteurl, is_relative);
145                 } else if (starts_with_dot_slash(url))
146                         url += 2;
147                 else
148                         break;
149         }
150         strbuf_reset(&sb);
151         strbuf_addf(&sb, "%s%s%s", remoteurl, colonsep ? ":" : "/", url);
152         if (ends_with(url, "/"))
153                 strbuf_setlen(&sb, sb.len - 1);
154         free(remoteurl);
155
156         if (starts_with_dot_slash(sb.buf))
157                 out = xstrdup(sb.buf + 2);
158         else
159                 out = xstrdup(sb.buf);
160         strbuf_reset(&sb);
161
162         if (!up_path || !is_relative)
163                 return out;
164
165         strbuf_addf(&sb, "%s%s", up_path, out);
166         free(out);
167         return strbuf_detach(&sb, NULL);
168 }
169
170 static int resolve_relative_url(int argc, const char **argv, const char *prefix)
171 {
172         char *remoteurl = NULL;
173         char *remote = get_default_remote();
174         const char *up_path = NULL;
175         char *res;
176         const char *url;
177         struct strbuf sb = STRBUF_INIT;
178
179         if (argc != 2 && argc != 3)
180                 die("resolve-relative-url only accepts one or two arguments");
181
182         url = argv[1];
183         strbuf_addf(&sb, "remote.%s.url", remote);
184         free(remote);
185
186         if (git_config_get_string(sb.buf, &remoteurl))
187                 /* the repository is its own authoritative upstream */
188                 remoteurl = xgetcwd();
189
190         if (argc == 3)
191                 up_path = argv[2];
192
193         res = relative_url(remoteurl, url, up_path);
194         puts(res);
195         free(res);
196         free(remoteurl);
197         return 0;
198 }
199
200 static int resolve_relative_url_test(int argc, const char **argv, const char *prefix)
201 {
202         char *remoteurl, *res;
203         const char *up_path, *url;
204
205         if (argc != 4)
206                 die("resolve-relative-url-test only accepts three arguments: <up_path> <remoteurl> <url>");
207
208         up_path = argv[1];
209         remoteurl = xstrdup(argv[2]);
210         url = argv[3];
211
212         if (!strcmp(up_path, "(null)"))
213                 up_path = NULL;
214
215         res = relative_url(remoteurl, url, up_path);
216         puts(res);
217         free(res);
218         free(remoteurl);
219         return 0;
220 }
221
222 struct module_list {
223         const struct cache_entry **entries;
224         int alloc, nr;
225 };
226 #define MODULE_LIST_INIT { NULL, 0, 0 }
227
228 static int module_list_compute(int argc, const char **argv,
229                                const char *prefix,
230                                struct pathspec *pathspec,
231                                struct module_list *list)
232 {
233         int i, result = 0;
234         char *ps_matched = NULL;
235         parse_pathspec(pathspec, 0,
236                        PATHSPEC_PREFER_FULL |
237                        PATHSPEC_STRIP_SUBMODULE_SLASH_CHEAP,
238                        prefix, argv);
239
240         if (pathspec->nr)
241                 ps_matched = xcalloc(pathspec->nr, 1);
242
243         if (read_cache() < 0)
244                 die(_("index file corrupt"));
245
246         for (i = 0; i < active_nr; i++) {
247                 const struct cache_entry *ce = active_cache[i];
248
249                 if (!match_pathspec(pathspec, ce->name, ce_namelen(ce),
250                                     0, ps_matched, 1) ||
251                     !S_ISGITLINK(ce->ce_mode))
252                         continue;
253
254                 ALLOC_GROW(list->entries, list->nr + 1, list->alloc);
255                 list->entries[list->nr++] = ce;
256                 while (i + 1 < active_nr &&
257                        !strcmp(ce->name, active_cache[i + 1]->name))
258                         /*
259                          * Skip entries with the same name in different stages
260                          * to make sure an entry is returned only once.
261                          */
262                         i++;
263         }
264
265         if (ps_matched && report_path_error(ps_matched, pathspec, prefix))
266                 result = -1;
267
268         free(ps_matched);
269
270         return result;
271 }
272
273 static int module_list(int argc, const char **argv, const char *prefix)
274 {
275         int i;
276         struct pathspec pathspec;
277         struct module_list list = MODULE_LIST_INIT;
278
279         struct option module_list_options[] = {
280                 OPT_STRING(0, "prefix", &prefix,
281                            N_("path"),
282                            N_("alternative anchor for relative paths")),
283                 OPT_END()
284         };
285
286         const char *const git_submodule_helper_usage[] = {
287                 N_("git submodule--helper list [--prefix=<path>] [<path>...]"),
288                 NULL
289         };
290
291         argc = parse_options(argc, argv, prefix, module_list_options,
292                              git_submodule_helper_usage, 0);
293
294         if (module_list_compute(argc, argv, prefix, &pathspec, &list) < 0)
295                 return 1;
296
297         for (i = 0; i < list.nr; i++) {
298                 const struct cache_entry *ce = list.entries[i];
299
300                 if (ce_stage(ce))
301                         printf("%06o %s U\t", ce->ce_mode, sha1_to_hex(null_sha1));
302                 else
303                         printf("%06o %s %d\t", ce->ce_mode,
304                                oid_to_hex(&ce->oid), ce_stage(ce));
305
306                 utf8_fprintf(stdout, "%s\n", ce->name);
307         }
308         return 0;
309 }
310
311 static void init_submodule(const char *path, const char *prefix, int quiet)
312 {
313         const struct submodule *sub;
314         struct strbuf sb = STRBUF_INIT;
315         char *upd = NULL, *url = NULL, *displaypath;
316
317         /* Only loads from .gitmodules, no overlay with .git/config */
318         gitmodules_config();
319
320         if (prefix) {
321                 strbuf_addf(&sb, "%s%s", prefix, path);
322                 displaypath = strbuf_detach(&sb, NULL);
323         } else
324                 displaypath = xstrdup(path);
325
326         sub = submodule_from_path(null_sha1, path);
327
328         if (!sub)
329                 die(_("No url found for submodule path '%s' in .gitmodules"),
330                         displaypath);
331
332         /*
333          * Copy url setting when it is not set yet.
334          * To look up the url in .git/config, we must not fall back to
335          * .gitmodules, so look it up directly.
336          */
337         strbuf_reset(&sb);
338         strbuf_addf(&sb, "submodule.%s.url", sub->name);
339         if (git_config_get_string(sb.buf, &url)) {
340                 url = xstrdup(sub->url);
341
342                 if (!url)
343                         die(_("No url found for submodule path '%s' in .gitmodules"),
344                                 displaypath);
345
346                 /* Possibly a url relative to parent */
347                 if (starts_with_dot_dot_slash(url) ||
348                     starts_with_dot_slash(url)) {
349                         char *remoteurl, *relurl;
350                         char *remote = get_default_remote();
351                         struct strbuf remotesb = STRBUF_INIT;
352                         strbuf_addf(&remotesb, "remote.%s.url", remote);
353                         free(remote);
354
355                         if (git_config_get_string(remotesb.buf, &remoteurl))
356                                 /*
357                                  * The repository is its own
358                                  * authoritative upstream
359                                  */
360                                 remoteurl = xgetcwd();
361                         relurl = relative_url(remoteurl, url, NULL);
362                         strbuf_release(&remotesb);
363                         free(remoteurl);
364                         free(url);
365                         url = relurl;
366                 }
367
368                 if (git_config_set_gently(sb.buf, url))
369                         die(_("Failed to register url for submodule path '%s'"),
370                             displaypath);
371                 if (!quiet)
372                         fprintf(stderr,
373                                 _("Submodule '%s' (%s) registered for path '%s'\n"),
374                                 sub->name, url, displaypath);
375         }
376
377         /* Copy "update" setting when it is not set yet */
378         strbuf_reset(&sb);
379         strbuf_addf(&sb, "submodule.%s.update", sub->name);
380         if (git_config_get_string(sb.buf, &upd) &&
381             sub->update_strategy.type != SM_UPDATE_UNSPECIFIED) {
382                 if (sub->update_strategy.type == SM_UPDATE_COMMAND) {
383                         fprintf(stderr, _("warning: command update mode suggested for submodule '%s'\n"),
384                                 sub->name);
385                         upd = xstrdup("none");
386                 } else
387                         upd = xstrdup(submodule_strategy_to_string(&sub->update_strategy));
388
389                 if (git_config_set_gently(sb.buf, upd))
390                         die(_("Failed to register update mode for submodule path '%s'"), displaypath);
391         }
392         strbuf_release(&sb);
393         free(displaypath);
394         free(url);
395         free(upd);
396 }
397
398 static int module_init(int argc, const char **argv, const char *prefix)
399 {
400         struct pathspec pathspec;
401         struct module_list list = MODULE_LIST_INIT;
402         int quiet = 0;
403         int i;
404
405         struct option module_init_options[] = {
406                 OPT_STRING(0, "prefix", &prefix,
407                            N_("path"),
408                            N_("alternative anchor for relative paths")),
409                 OPT__QUIET(&quiet, N_("Suppress output for initializing a submodule")),
410                 OPT_END()
411         };
412
413         const char *const git_submodule_helper_usage[] = {
414                 N_("git submodule--helper init [<path>]"),
415                 NULL
416         };
417
418         argc = parse_options(argc, argv, prefix, module_init_options,
419                              git_submodule_helper_usage, 0);
420
421         if (module_list_compute(argc, argv, prefix, &pathspec, &list) < 0)
422                 return 1;
423
424         for (i = 0; i < list.nr; i++)
425                 init_submodule(list.entries[i]->name, prefix, quiet);
426
427         return 0;
428 }
429
430 static int module_name(int argc, const char **argv, const char *prefix)
431 {
432         const struct submodule *sub;
433
434         if (argc != 2)
435                 usage(_("git submodule--helper name <path>"));
436
437         gitmodules_config();
438         sub = submodule_from_path(null_sha1, argv[1]);
439
440         if (!sub)
441                 die(_("no submodule mapping found in .gitmodules for path '%s'"),
442                     argv[1]);
443
444         printf("%s\n", sub->name);
445
446         return 0;
447 }
448
449 static int clone_submodule(const char *path, const char *gitdir, const char *url,
450                            const char *depth, struct string_list *reference,
451                            int quiet, int progress)
452 {
453         struct child_process cp = CHILD_PROCESS_INIT;
454
455         argv_array_push(&cp.args, "clone");
456         argv_array_push(&cp.args, "--no-checkout");
457         if (quiet)
458                 argv_array_push(&cp.args, "--quiet");
459         if (progress)
460                 argv_array_push(&cp.args, "--progress");
461         if (depth && *depth)
462                 argv_array_pushl(&cp.args, "--depth", depth, NULL);
463         if (reference->nr) {
464                 struct string_list_item *item;
465                 for_each_string_list_item(item, reference)
466                         argv_array_pushl(&cp.args, "--reference",
467                                          item->string, NULL);
468         }
469         if (gitdir && *gitdir)
470                 argv_array_pushl(&cp.args, "--separate-git-dir", gitdir, NULL);
471
472         argv_array_push(&cp.args, url);
473         argv_array_push(&cp.args, path);
474
475         cp.git_cmd = 1;
476         prepare_submodule_repo_env(&cp.env_array);
477         cp.no_stdin = 1;
478
479         return run_command(&cp);
480 }
481
482 struct submodule_alternate_setup {
483         const char *submodule_name;
484         enum SUBMODULE_ALTERNATE_ERROR_MODE {
485                 SUBMODULE_ALTERNATE_ERROR_DIE,
486                 SUBMODULE_ALTERNATE_ERROR_INFO,
487                 SUBMODULE_ALTERNATE_ERROR_IGNORE
488         } error_mode;
489         struct string_list *reference;
490 };
491 #define SUBMODULE_ALTERNATE_SETUP_INIT { NULL, \
492         SUBMODULE_ALTERNATE_ERROR_IGNORE, NULL }
493
494 static int add_possible_reference_from_superproject(
495                 struct alternate_object_database *alt, void *sas_cb)
496 {
497         struct submodule_alternate_setup *sas = sas_cb;
498
499         /*
500          * If the alternate object store is another repository, try the
501          * standard layout with .git/(modules/<name>)+/objects
502          */
503         if (ends_with(alt->path, "/objects")) {
504                 char *sm_alternate;
505                 struct strbuf sb = STRBUF_INIT;
506                 struct strbuf err = STRBUF_INIT;
507                 strbuf_add(&sb, alt->path, strlen(alt->path) - strlen("objects"));
508
509                 /*
510                  * We need to end the new path with '/' to mark it as a dir,
511                  * otherwise a submodule name containing '/' will be broken
512                  * as the last part of a missing submodule reference would
513                  * be taken as a file name.
514                  */
515                 strbuf_addf(&sb, "modules/%s/", sas->submodule_name);
516
517                 sm_alternate = compute_alternate_path(sb.buf, &err);
518                 if (sm_alternate) {
519                         string_list_append(sas->reference, xstrdup(sb.buf));
520                         free(sm_alternate);
521                 } else {
522                         switch (sas->error_mode) {
523                         case SUBMODULE_ALTERNATE_ERROR_DIE:
524                                 die(_("submodule '%s' cannot add alternate: %s"),
525                                     sas->submodule_name, err.buf);
526                         case SUBMODULE_ALTERNATE_ERROR_INFO:
527                                 fprintf(stderr, _("submodule '%s' cannot add alternate: %s"),
528                                         sas->submodule_name, err.buf);
529                         case SUBMODULE_ALTERNATE_ERROR_IGNORE:
530                                 ; /* nothing */
531                         }
532                 }
533                 strbuf_release(&sb);
534         }
535
536         return 0;
537 }
538
539 static void prepare_possible_alternates(const char *sm_name,
540                 struct string_list *reference)
541 {
542         char *sm_alternate = NULL, *error_strategy = NULL;
543         struct submodule_alternate_setup sas = SUBMODULE_ALTERNATE_SETUP_INIT;
544
545         git_config_get_string("submodule.alternateLocation", &sm_alternate);
546         if (!sm_alternate)
547                 return;
548
549         git_config_get_string("submodule.alternateErrorStrategy", &error_strategy);
550
551         if (!error_strategy)
552                 error_strategy = xstrdup("die");
553
554         sas.submodule_name = sm_name;
555         sas.reference = reference;
556         if (!strcmp(error_strategy, "die"))
557                 sas.error_mode = SUBMODULE_ALTERNATE_ERROR_DIE;
558         else if (!strcmp(error_strategy, "info"))
559                 sas.error_mode = SUBMODULE_ALTERNATE_ERROR_INFO;
560         else if (!strcmp(error_strategy, "ignore"))
561                 sas.error_mode = SUBMODULE_ALTERNATE_ERROR_IGNORE;
562         else
563                 die(_("Value '%s' for submodule.alternateErrorStrategy is not recognized"), error_strategy);
564
565         if (!strcmp(sm_alternate, "superproject"))
566                 foreach_alt_odb(add_possible_reference_from_superproject, &sas);
567         else if (!strcmp(sm_alternate, "no"))
568                 ; /* do nothing */
569         else
570                 die(_("Value '%s' for submodule.alternateLocation is not recognized"), sm_alternate);
571
572         free(sm_alternate);
573         free(error_strategy);
574 }
575
576 static int module_clone(int argc, const char **argv, const char *prefix)
577 {
578         const char *name = NULL, *url = NULL, *depth = NULL;
579         int quiet = 0;
580         int progress = 0;
581         FILE *submodule_dot_git;
582         char *p, *path = NULL, *sm_gitdir;
583         struct strbuf rel_path = STRBUF_INIT;
584         struct strbuf sb = STRBUF_INIT;
585         struct string_list reference = STRING_LIST_INIT_NODUP;
586         char *sm_alternate = NULL, *error_strategy = NULL;
587
588         struct option module_clone_options[] = {
589                 OPT_STRING(0, "prefix", &prefix,
590                            N_("path"),
591                            N_("alternative anchor for relative paths")),
592                 OPT_STRING(0, "path", &path,
593                            N_("path"),
594                            N_("where the new submodule will be cloned to")),
595                 OPT_STRING(0, "name", &name,
596                            N_("string"),
597                            N_("name of the new submodule")),
598                 OPT_STRING(0, "url", &url,
599                            N_("string"),
600                            N_("url where to clone the submodule from")),
601                 OPT_STRING_LIST(0, "reference", &reference,
602                            N_("repo"),
603                            N_("reference repository")),
604                 OPT_STRING(0, "depth", &depth,
605                            N_("string"),
606                            N_("depth for shallow clones")),
607                 OPT__QUIET(&quiet, "Suppress output for cloning a submodule"),
608                 OPT_BOOL(0, "progress", &progress,
609                            N_("force cloning progress")),
610                 OPT_END()
611         };
612
613         const char *const git_submodule_helper_usage[] = {
614                 N_("git submodule--helper clone [--prefix=<path>] [--quiet] "
615                    "[--reference <repository>] [--name <name>] [--depth <depth>] "
616                    "--url <url> --path <path>"),
617                 NULL
618         };
619
620         argc = parse_options(argc, argv, prefix, module_clone_options,
621                              git_submodule_helper_usage, 0);
622
623         if (argc || !url || !path || !*path)
624                 usage_with_options(git_submodule_helper_usage,
625                                    module_clone_options);
626
627         strbuf_addf(&sb, "%s/modules/%s", get_git_dir(), name);
628         sm_gitdir = xstrdup(absolute_path(sb.buf));
629         strbuf_reset(&sb);
630
631         if (!is_absolute_path(path)) {
632                 strbuf_addf(&sb, "%s/%s", get_git_work_tree(), path);
633                 path = strbuf_detach(&sb, NULL);
634         } else
635                 path = xstrdup(path);
636
637         if (!file_exists(sm_gitdir)) {
638                 if (safe_create_leading_directories_const(sm_gitdir) < 0)
639                         die(_("could not create directory '%s'"), sm_gitdir);
640
641                 prepare_possible_alternates(name, &reference);
642
643                 if (clone_submodule(path, sm_gitdir, url, depth, &reference,
644                                     quiet, progress))
645                         die(_("clone of '%s' into submodule path '%s' failed"),
646                             url, path);
647         } else {
648                 if (safe_create_leading_directories_const(path) < 0)
649                         die(_("could not create directory '%s'"), path);
650                 strbuf_addf(&sb, "%s/index", sm_gitdir);
651                 unlink_or_warn(sb.buf);
652                 strbuf_reset(&sb);
653         }
654
655         /* Write a .git file in the submodule to redirect to the superproject. */
656         strbuf_addf(&sb, "%s/.git", path);
657         if (safe_create_leading_directories_const(sb.buf) < 0)
658                 die(_("could not create leading directories of '%s'"), sb.buf);
659         submodule_dot_git = fopen(sb.buf, "w");
660         if (!submodule_dot_git)
661                 die_errno(_("cannot open file '%s'"), sb.buf);
662
663         fprintf_or_die(submodule_dot_git, "gitdir: %s\n",
664                        relative_path(sm_gitdir, path, &rel_path));
665         if (fclose(submodule_dot_git))
666                 die(_("could not close file %s"), sb.buf);
667         strbuf_reset(&sb);
668         strbuf_reset(&rel_path);
669
670         /* Redirect the worktree of the submodule in the superproject's config */
671         p = git_pathdup_submodule(path, "config");
672         if (!p)
673                 die(_("could not get submodule directory for '%s'"), path);
674         git_config_set_in_file(p, "core.worktree",
675                                relative_path(path, sm_gitdir, &rel_path));
676
677         /* setup alternateLocation and alternateErrorStrategy in the cloned submodule if needed */
678         git_config_get_string("submodule.alternateLocation", &sm_alternate);
679         if (sm_alternate)
680                 git_config_set_in_file(p, "submodule.alternateLocation",
681                                            sm_alternate);
682         git_config_get_string("submodule.alternateErrorStrategy", &error_strategy);
683         if (error_strategy)
684                 git_config_set_in_file(p, "submodule.alternateErrorStrategy",
685                                            error_strategy);
686
687         free(sm_alternate);
688         free(error_strategy);
689
690         strbuf_release(&sb);
691         strbuf_release(&rel_path);
692         free(sm_gitdir);
693         free(path);
694         free(p);
695         return 0;
696 }
697
698 struct submodule_update_clone {
699         /* index into 'list', the list of submodules to look into for cloning */
700         int current;
701         struct module_list list;
702         unsigned warn_if_uninitialized : 1;
703
704         /* update parameter passed via commandline */
705         struct submodule_update_strategy update;
706
707         /* configuration parameters which are passed on to the children */
708         int progress;
709         int quiet;
710         int recommend_shallow;
711         struct string_list references;
712         const char *depth;
713         const char *recursive_prefix;
714         const char *prefix;
715
716         /* Machine-readable status lines to be consumed by git-submodule.sh */
717         struct string_list projectlines;
718
719         /* If we want to stop as fast as possible and return an error */
720         unsigned quickstop : 1;
721
722         /* failed clones to be retried again */
723         const struct cache_entry **failed_clones;
724         int failed_clones_nr, failed_clones_alloc;
725 };
726 #define SUBMODULE_UPDATE_CLONE_INIT {0, MODULE_LIST_INIT, 0, \
727         SUBMODULE_UPDATE_STRATEGY_INIT, 0, 0, -1, STRING_LIST_INIT_DUP, \
728         NULL, NULL, NULL, \
729         STRING_LIST_INIT_DUP, 0, NULL, 0, 0}
730
731
732 static void next_submodule_warn_missing(struct submodule_update_clone *suc,
733                 struct strbuf *out, const char *displaypath)
734 {
735         /*
736          * Only mention uninitialized submodules when their
737          * paths have been specified.
738          */
739         if (suc->warn_if_uninitialized) {
740                 strbuf_addf(out,
741                         _("Submodule path '%s' not initialized"),
742                         displaypath);
743                 strbuf_addch(out, '\n');
744                 strbuf_addstr(out,
745                         _("Maybe you want to use 'update --init'?"));
746                 strbuf_addch(out, '\n');
747         }
748 }
749
750 /**
751  * Determine whether 'ce' needs to be cloned. If so, prepare the 'child' to
752  * run the clone. Returns 1 if 'ce' needs to be cloned, 0 otherwise.
753  */
754 static int prepare_to_clone_next_submodule(const struct cache_entry *ce,
755                                            struct child_process *child,
756                                            struct submodule_update_clone *suc,
757                                            struct strbuf *out)
758 {
759         const struct submodule *sub = NULL;
760         struct strbuf displaypath_sb = STRBUF_INIT;
761         struct strbuf sb = STRBUF_INIT;
762         const char *displaypath = NULL;
763         char *url = NULL;
764         int needs_cloning = 0;
765
766         if (ce_stage(ce)) {
767                 if (suc->recursive_prefix)
768                         strbuf_addf(&sb, "%s/%s", suc->recursive_prefix, ce->name);
769                 else
770                         strbuf_addstr(&sb, ce->name);
771                 strbuf_addf(out, _("Skipping unmerged submodule %s"), sb.buf);
772                 strbuf_addch(out, '\n');
773                 goto cleanup;
774         }
775
776         sub = submodule_from_path(null_sha1, ce->name);
777
778         if (suc->recursive_prefix)
779                 displaypath = relative_path(suc->recursive_prefix,
780                                             ce->name, &displaypath_sb);
781         else
782                 displaypath = ce->name;
783
784         if (!sub) {
785                 next_submodule_warn_missing(suc, out, displaypath);
786                 goto cleanup;
787         }
788
789         if (suc->update.type == SM_UPDATE_NONE
790             || (suc->update.type == SM_UPDATE_UNSPECIFIED
791                 && sub->update_strategy.type == SM_UPDATE_NONE)) {
792                 strbuf_addf(out, _("Skipping submodule '%s'"), displaypath);
793                 strbuf_addch(out, '\n');
794                 goto cleanup;
795         }
796
797         /*
798          * Looking up the url in .git/config.
799          * We must not fall back to .gitmodules as we only want
800          * to process configured submodules.
801          */
802         strbuf_reset(&sb);
803         strbuf_addf(&sb, "submodule.%s.url", sub->name);
804         git_config_get_string(sb.buf, &url);
805         if (!url) {
806                 next_submodule_warn_missing(suc, out, displaypath);
807                 goto cleanup;
808         }
809
810         strbuf_reset(&sb);
811         strbuf_addf(&sb, "%s/.git", ce->name);
812         needs_cloning = !file_exists(sb.buf);
813
814         strbuf_reset(&sb);
815         strbuf_addf(&sb, "%06o %s %d %d\t%s\n", ce->ce_mode,
816                         oid_to_hex(&ce->oid), ce_stage(ce),
817                         needs_cloning, ce->name);
818         string_list_append(&suc->projectlines, sb.buf);
819
820         if (!needs_cloning)
821                 goto cleanup;
822
823         child->git_cmd = 1;
824         child->no_stdin = 1;
825         child->stdout_to_stderr = 1;
826         child->err = -1;
827         argv_array_push(&child->args, "submodule--helper");
828         argv_array_push(&child->args, "clone");
829         if (suc->progress)
830                 argv_array_push(&child->args, "--progress");
831         if (suc->quiet)
832                 argv_array_push(&child->args, "--quiet");
833         if (suc->prefix)
834                 argv_array_pushl(&child->args, "--prefix", suc->prefix, NULL);
835         if (suc->recommend_shallow && sub->recommend_shallow == 1)
836                 argv_array_push(&child->args, "--depth=1");
837         argv_array_pushl(&child->args, "--path", sub->path, NULL);
838         argv_array_pushl(&child->args, "--name", sub->name, NULL);
839         argv_array_pushl(&child->args, "--url", url, NULL);
840         if (suc->references.nr) {
841                 struct string_list_item *item;
842                 for_each_string_list_item(item, &suc->references)
843                         argv_array_pushl(&child->args, "--reference", item->string, NULL);
844         }
845         if (suc->depth)
846                 argv_array_push(&child->args, suc->depth);
847
848 cleanup:
849         free(url);
850         strbuf_reset(&displaypath_sb);
851         strbuf_reset(&sb);
852
853         return needs_cloning;
854 }
855
856 static int update_clone_get_next_task(struct child_process *child,
857                                       struct strbuf *err,
858                                       void *suc_cb,
859                                       void **idx_task_cb)
860 {
861         struct submodule_update_clone *suc = suc_cb;
862         const struct cache_entry *ce;
863         int index;
864
865         for (; suc->current < suc->list.nr; suc->current++) {
866                 ce = suc->list.entries[suc->current];
867                 if (prepare_to_clone_next_submodule(ce, child, suc, err)) {
868                         int *p = xmalloc(sizeof(*p));
869                         *p = suc->current;
870                         *idx_task_cb = p;
871                         suc->current++;
872                         return 1;
873                 }
874         }
875
876         /*
877          * The loop above tried cloning each submodule once, now try the
878          * stragglers again, which we can imagine as an extension of the
879          * entry list.
880          */
881         index = suc->current - suc->list.nr;
882         if (index < suc->failed_clones_nr) {
883                 int *p;
884                 ce = suc->failed_clones[index];
885                 if (!prepare_to_clone_next_submodule(ce, child, suc, err)) {
886                         suc->current ++;
887                         strbuf_addstr(err, "BUG: submodule considered for "
888                                            "cloning, doesn't need cloning "
889                                            "any more?\n");
890                         return 0;
891                 }
892                 p = xmalloc(sizeof(*p));
893                 *p = suc->current;
894                 *idx_task_cb = p;
895                 suc->current ++;
896                 return 1;
897         }
898
899         return 0;
900 }
901
902 static int update_clone_start_failure(struct strbuf *err,
903                                       void *suc_cb,
904                                       void *idx_task_cb)
905 {
906         struct submodule_update_clone *suc = suc_cb;
907         suc->quickstop = 1;
908         return 1;
909 }
910
911 static int update_clone_task_finished(int result,
912                                       struct strbuf *err,
913                                       void *suc_cb,
914                                       void *idx_task_cb)
915 {
916         const struct cache_entry *ce;
917         struct submodule_update_clone *suc = suc_cb;
918
919         int *idxP = *(int**)idx_task_cb;
920         int idx = *idxP;
921         free(idxP);
922
923         if (!result)
924                 return 0;
925
926         if (idx < suc->list.nr) {
927                 ce  = suc->list.entries[idx];
928                 strbuf_addf(err, _("Failed to clone '%s'. Retry scheduled"),
929                             ce->name);
930                 strbuf_addch(err, '\n');
931                 ALLOC_GROW(suc->failed_clones,
932                            suc->failed_clones_nr + 1,
933                            suc->failed_clones_alloc);
934                 suc->failed_clones[suc->failed_clones_nr++] = ce;
935                 return 0;
936         } else {
937                 idx -= suc->list.nr;
938                 ce  = suc->failed_clones[idx];
939                 strbuf_addf(err, _("Failed to clone '%s' a second time, aborting"),
940                             ce->name);
941                 strbuf_addch(err, '\n');
942                 suc->quickstop = 1;
943                 return 1;
944         }
945
946         return 0;
947 }
948
949 static int update_clone(int argc, const char **argv, const char *prefix)
950 {
951         const char *update = NULL;
952         int max_jobs = -1;
953         struct string_list_item *item;
954         struct pathspec pathspec;
955         struct submodule_update_clone suc = SUBMODULE_UPDATE_CLONE_INIT;
956
957         struct option module_update_clone_options[] = {
958                 OPT_STRING(0, "prefix", &prefix,
959                            N_("path"),
960                            N_("path into the working tree")),
961                 OPT_STRING(0, "recursive-prefix", &suc.recursive_prefix,
962                            N_("path"),
963                            N_("path into the working tree, across nested "
964                               "submodule boundaries")),
965                 OPT_STRING(0, "update", &update,
966                            N_("string"),
967                            N_("rebase, merge, checkout or none")),
968                 OPT_STRING_LIST(0, "reference", &suc.references, N_("repo"),
969                            N_("reference repository")),
970                 OPT_STRING(0, "depth", &suc.depth, "<depth>",
971                            N_("Create a shallow clone truncated to the "
972                               "specified number of revisions")),
973                 OPT_INTEGER('j', "jobs", &max_jobs,
974                             N_("parallel jobs")),
975                 OPT_BOOL(0, "recommend-shallow", &suc.recommend_shallow,
976                             N_("whether the initial clone should follow the shallow recommendation")),
977                 OPT__QUIET(&suc.quiet, N_("don't print cloning progress")),
978                 OPT_BOOL(0, "progress", &suc.progress,
979                             N_("force cloning progress")),
980                 OPT_END()
981         };
982
983         const char *const git_submodule_helper_usage[] = {
984                 N_("git submodule--helper update_clone [--prefix=<path>] [<path>...]"),
985                 NULL
986         };
987         suc.prefix = prefix;
988
989         argc = parse_options(argc, argv, prefix, module_update_clone_options,
990                              git_submodule_helper_usage, 0);
991
992         if (update)
993                 if (parse_submodule_update_strategy(update, &suc.update) < 0)
994                         die(_("bad value for update parameter"));
995
996         if (module_list_compute(argc, argv, prefix, &pathspec, &suc.list) < 0)
997                 return 1;
998
999         if (pathspec.nr)
1000                 suc.warn_if_uninitialized = 1;
1001
1002         /* Overlay the parsed .gitmodules file with .git/config */
1003         gitmodules_config();
1004         git_config(submodule_config, NULL);
1005
1006         if (max_jobs < 0)
1007                 max_jobs = parallel_submodules();
1008
1009         run_processes_parallel(max_jobs,
1010                                update_clone_get_next_task,
1011                                update_clone_start_failure,
1012                                update_clone_task_finished,
1013                                &suc);
1014
1015         /*
1016          * We saved the output and put it out all at once now.
1017          * That means:
1018          * - the listener does not have to interleave their (checkout)
1019          *   work with our fetching.  The writes involved in a
1020          *   checkout involve more straightforward sequential I/O.
1021          * - the listener can avoid doing any work if fetching failed.
1022          */
1023         if (suc.quickstop)
1024                 return 1;
1025
1026         for_each_string_list_item(item, &suc.projectlines)
1027                 utf8_fprintf(stdout, "%s", item->string);
1028
1029         return 0;
1030 }
1031
1032 static int resolve_relative_path(int argc, const char **argv, const char *prefix)
1033 {
1034         struct strbuf sb = STRBUF_INIT;
1035         if (argc != 3)
1036                 die("submodule--helper relative-path takes exactly 2 arguments, got %d", argc);
1037
1038         printf("%s", relative_path(argv[1], argv[2], &sb));
1039         strbuf_release(&sb);
1040         return 0;
1041 }
1042
1043 static const char *remote_submodule_branch(const char *path)
1044 {
1045         const struct submodule *sub;
1046         gitmodules_config();
1047         git_config(submodule_config, NULL);
1048
1049         sub = submodule_from_path(null_sha1, path);
1050         if (!sub)
1051                 return NULL;
1052
1053         if (!sub->branch)
1054                 return "master";
1055
1056         if (!strcmp(sub->branch, ".")) {
1057                 unsigned char sha1[20];
1058                 const char *refname = resolve_ref_unsafe("HEAD", 0, sha1, NULL);
1059
1060                 if (!refname)
1061                         die(_("No such ref: %s"), "HEAD");
1062
1063                 /* detached HEAD */
1064                 if (!strcmp(refname, "HEAD"))
1065                         die(_("Submodule (%s) branch configured to inherit "
1066                               "branch from superproject, but the superproject "
1067                               "is not on any branch"), sub->name);
1068
1069                 if (!skip_prefix(refname, "refs/heads/", &refname))
1070                         die(_("Expecting a full ref name, got %s"), refname);
1071                 return refname;
1072         }
1073
1074         return sub->branch;
1075 }
1076
1077 static int resolve_remote_submodule_branch(int argc, const char **argv,
1078                 const char *prefix)
1079 {
1080         const char *ret;
1081         struct strbuf sb = STRBUF_INIT;
1082         if (argc != 2)
1083                 die("submodule--helper remote-branch takes exactly one arguments, got %d", argc);
1084
1085         ret = remote_submodule_branch(argv[1]);
1086         if (!ret)
1087                 die("submodule %s doesn't exist", argv[1]);
1088
1089         printf("%s", ret);
1090         strbuf_release(&sb);
1091         return 0;
1092 }
1093
1094 static int absorb_git_dirs(int argc, const char **argv, const char *prefix)
1095 {
1096         int i;
1097         struct pathspec pathspec;
1098         struct module_list list = MODULE_LIST_INIT;
1099         unsigned flags = ABSORB_GITDIR_RECURSE_SUBMODULES;
1100
1101         struct option embed_gitdir_options[] = {
1102                 OPT_STRING(0, "prefix", &prefix,
1103                            N_("path"),
1104                            N_("path into the working tree")),
1105                 OPT_BIT(0, "--recursive", &flags, N_("recurse into submodules"),
1106                         ABSORB_GITDIR_RECURSE_SUBMODULES),
1107                 OPT_END()
1108         };
1109
1110         const char *const git_submodule_helper_usage[] = {
1111                 N_("git submodule--helper embed-git-dir [<path>...]"),
1112                 NULL
1113         };
1114
1115         argc = parse_options(argc, argv, prefix, embed_gitdir_options,
1116                              git_submodule_helper_usage, 0);
1117
1118         gitmodules_config();
1119         git_config(submodule_config, NULL);
1120
1121         if (module_list_compute(argc, argv, prefix, &pathspec, &list) < 0)
1122                 return 1;
1123
1124         for (i = 0; i < list.nr; i++)
1125                 absorb_git_dir_into_superproject(prefix,
1126                                 list.entries[i]->name, flags);
1127
1128         return 0;
1129 }
1130
1131 #define SUPPORT_SUPER_PREFIX (1<<0)
1132
1133 struct cmd_struct {
1134         const char *cmd;
1135         int (*fn)(int, const char **, const char *);
1136         unsigned option;
1137 };
1138
1139 static struct cmd_struct commands[] = {
1140         {"list", module_list, 0},
1141         {"name", module_name, 0},
1142         {"clone", module_clone, 0},
1143         {"update-clone", update_clone, 0},
1144         {"relative-path", resolve_relative_path, 0},
1145         {"resolve-relative-url", resolve_relative_url, 0},
1146         {"resolve-relative-url-test", resolve_relative_url_test, 0},
1147         {"init", module_init, 0},
1148         {"remote-branch", resolve_remote_submodule_branch, 0},
1149         {"absorb-git-dirs", absorb_git_dirs, SUPPORT_SUPER_PREFIX},
1150 };
1151
1152 int cmd_submodule__helper(int argc, const char **argv, const char *prefix)
1153 {
1154         int i;
1155         if (argc < 2)
1156                 die(_("submodule--helper subcommand must be "
1157                       "called with a subcommand"));
1158
1159         for (i = 0; i < ARRAY_SIZE(commands); i++) {
1160                 if (!strcmp(argv[1], commands[i].cmd)) {
1161                         if (get_super_prefix() &&
1162                             !(commands[i].option & SUPPORT_SUPER_PREFIX))
1163                                 die(_("%s doesn't support --super-prefix"),
1164                                     commands[i].cmd);
1165                         return commands[i].fn(argc - 1, argv + 1, prefix);
1166                 }
1167         }
1168
1169         die(_("'%s' is not a valid submodule--helper "
1170               "subcommand"), argv[1]);
1171 }