Merge branch 'sb/worktree-remove-opt-force'
[git] / submodule.c
1 #define NO_THE_INDEX_COMPATIBILITY_MACROS
2
3 #include "cache.h"
4 #include "repository.h"
5 #include "config.h"
6 #include "submodule-config.h"
7 #include "submodule.h"
8 #include "dir.h"
9 #include "diff.h"
10 #include "commit.h"
11 #include "revision.h"
12 #include "run-command.h"
13 #include "diffcore.h"
14 #include "refs.h"
15 #include "string-list.h"
16 #include "sha1-array.h"
17 #include "argv-array.h"
18 #include "blob.h"
19 #include "thread-utils.h"
20 #include "quote.h"
21 #include "remote.h"
22 #include "worktree.h"
23 #include "parse-options.h"
24 #include "object-store.h"
25
26 static int config_update_recurse_submodules = RECURSE_SUBMODULES_OFF;
27 static struct string_list changed_submodule_names = STRING_LIST_INIT_DUP;
28 static int initialized_fetch_ref_tips;
29 static struct oid_array ref_tips_before_fetch;
30 static struct oid_array ref_tips_after_fetch;
31
32 /*
33  * Check if the .gitmodules file is unmerged. Parsing of the .gitmodules file
34  * will be disabled because we can't guess what might be configured in
35  * .gitmodules unless the user resolves the conflict.
36  */
37 int is_gitmodules_unmerged(const struct index_state *istate)
38 {
39         int pos = index_name_pos(istate, GITMODULES_FILE, strlen(GITMODULES_FILE));
40         if (pos < 0) { /* .gitmodules not found or isn't merged */
41                 pos = -1 - pos;
42                 if (istate->cache_nr > pos) {  /* there is a .gitmodules */
43                         const struct cache_entry *ce = istate->cache[pos];
44                         if (ce_namelen(ce) == strlen(GITMODULES_FILE) &&
45                             !strcmp(ce->name, GITMODULES_FILE))
46                                 return 1;
47                 }
48         }
49
50         return 0;
51 }
52
53 /*
54  * Check if the .gitmodules file has unstaged modifications.  This must be
55  * checked before allowing modifications to the .gitmodules file with the
56  * intention to stage them later, because when continuing we would stage the
57  * modifications the user didn't stage herself too. That might change in a
58  * future version when we learn to stage the changes we do ourselves without
59  * staging any previous modifications.
60  */
61 int is_staging_gitmodules_ok(struct index_state *istate)
62 {
63         int pos = index_name_pos(istate, GITMODULES_FILE, strlen(GITMODULES_FILE));
64
65         if ((pos >= 0) && (pos < istate->cache_nr)) {
66                 struct stat st;
67                 if (lstat(GITMODULES_FILE, &st) == 0 &&
68                     ie_match_stat(istate, istate->cache[pos], &st,
69                                   CE_MATCH_IGNORE_FSMONITOR) & DATA_CHANGED)
70                         return 0;
71         }
72
73         return 1;
74 }
75
76 static int for_each_remote_ref_submodule(const char *submodule,
77                                          each_ref_fn fn, void *cb_data)
78 {
79         return refs_for_each_remote_ref(get_submodule_ref_store(submodule),
80                                         fn, cb_data);
81 }
82
83 /*
84  * Try to update the "path" entry in the "submodule.<name>" section of the
85  * .gitmodules file. Return 0 only if a .gitmodules file was found, a section
86  * with the correct path=<oldpath> setting was found and we could update it.
87  */
88 int update_path_in_gitmodules(const char *oldpath, const char *newpath)
89 {
90         struct strbuf entry = STRBUF_INIT;
91         const struct submodule *submodule;
92
93         if (!file_exists(GITMODULES_FILE)) /* Do nothing without .gitmodules */
94                 return -1;
95
96         if (is_gitmodules_unmerged(&the_index))
97                 die(_("Cannot change unmerged .gitmodules, resolve merge conflicts first"));
98
99         submodule = submodule_from_path(the_repository, &null_oid, oldpath);
100         if (!submodule || !submodule->name) {
101                 warning(_("Could not find section in .gitmodules where path=%s"), oldpath);
102                 return -1;
103         }
104         strbuf_addstr(&entry, "submodule.");
105         strbuf_addstr(&entry, submodule->name);
106         strbuf_addstr(&entry, ".path");
107         if (git_config_set_in_file_gently(GITMODULES_FILE, entry.buf, newpath) < 0) {
108                 /* Maybe the user already did that, don't error out here */
109                 warning(_("Could not update .gitmodules entry %s"), entry.buf);
110                 strbuf_release(&entry);
111                 return -1;
112         }
113         strbuf_release(&entry);
114         return 0;
115 }
116
117 /*
118  * Try to remove the "submodule.<name>" section from .gitmodules where the given
119  * path is configured. Return 0 only if a .gitmodules file was found, a section
120  * with the correct path=<path> setting was found and we could remove it.
121  */
122 int remove_path_from_gitmodules(const char *path)
123 {
124         struct strbuf sect = STRBUF_INIT;
125         const struct submodule *submodule;
126
127         if (!file_exists(GITMODULES_FILE)) /* Do nothing without .gitmodules */
128                 return -1;
129
130         if (is_gitmodules_unmerged(&the_index))
131                 die(_("Cannot change unmerged .gitmodules, resolve merge conflicts first"));
132
133         submodule = submodule_from_path(the_repository, &null_oid, path);
134         if (!submodule || !submodule->name) {
135                 warning(_("Could not find section in .gitmodules where path=%s"), path);
136                 return -1;
137         }
138         strbuf_addstr(&sect, "submodule.");
139         strbuf_addstr(&sect, submodule->name);
140         if (git_config_rename_section_in_file(GITMODULES_FILE, sect.buf, NULL) < 0) {
141                 /* Maybe the user already did that, don't error out here */
142                 warning(_("Could not remove .gitmodules entry for %s"), path);
143                 strbuf_release(&sect);
144                 return -1;
145         }
146         strbuf_release(&sect);
147         return 0;
148 }
149
150 void stage_updated_gitmodules(struct index_state *istate)
151 {
152         if (add_file_to_index(istate, GITMODULES_FILE, 0))
153                 die(_("staging updated .gitmodules failed"));
154 }
155
156 static int add_submodule_odb(const char *path)
157 {
158         struct strbuf objects_directory = STRBUF_INIT;
159         int ret = 0;
160
161         ret = strbuf_git_path_submodule(&objects_directory, path, "objects/");
162         if (ret)
163                 goto done;
164         if (!is_directory(objects_directory.buf)) {
165                 ret = -1;
166                 goto done;
167         }
168         add_to_alternates_memory(objects_directory.buf);
169 done:
170         strbuf_release(&objects_directory);
171         return ret;
172 }
173
174 void set_diffopt_flags_from_submodule_config(struct diff_options *diffopt,
175                                              const char *path)
176 {
177         const struct submodule *submodule = submodule_from_path(the_repository,
178                                                                 &null_oid, path);
179         if (submodule) {
180                 const char *ignore;
181                 char *key;
182
183                 key = xstrfmt("submodule.%s.ignore", submodule->name);
184                 if (repo_config_get_string_const(the_repository, key, &ignore))
185                         ignore = submodule->ignore;
186                 free(key);
187
188                 if (ignore)
189                         handle_ignore_submodules_arg(diffopt, ignore);
190                 else if (is_gitmodules_unmerged(&the_index))
191                         diffopt->flags.ignore_submodules = 1;
192         }
193 }
194
195 /* Cheap function that only determines if we're interested in submodules at all */
196 int git_default_submodule_config(const char *var, const char *value, void *cb)
197 {
198         if (!strcmp(var, "submodule.recurse")) {
199                 int v = git_config_bool(var, value) ?
200                         RECURSE_SUBMODULES_ON : RECURSE_SUBMODULES_OFF;
201                 config_update_recurse_submodules = v;
202         }
203         return 0;
204 }
205
206 int option_parse_recurse_submodules_worktree_updater(const struct option *opt,
207                                                      const char *arg, int unset)
208 {
209         if (unset) {
210                 config_update_recurse_submodules = RECURSE_SUBMODULES_OFF;
211                 return 0;
212         }
213         if (arg)
214                 config_update_recurse_submodules =
215                         parse_update_recurse_submodules_arg(opt->long_name,
216                                                             arg);
217         else
218                 config_update_recurse_submodules = RECURSE_SUBMODULES_ON;
219
220         return 0;
221 }
222
223 /*
224  * Determine if a submodule has been initialized at a given 'path'
225  */
226 int is_submodule_active(struct repository *repo, const char *path)
227 {
228         int ret = 0;
229         char *key = NULL;
230         char *value = NULL;
231         const struct string_list *sl;
232         const struct submodule *module;
233
234         module = submodule_from_path(repo, &null_oid, path);
235
236         /* early return if there isn't a path->module mapping */
237         if (!module)
238                 return 0;
239
240         /* submodule.<name>.active is set */
241         key = xstrfmt("submodule.%s.active", module->name);
242         if (!repo_config_get_bool(repo, key, &ret)) {
243                 free(key);
244                 return ret;
245         }
246         free(key);
247
248         /* submodule.active is set */
249         sl = repo_config_get_value_multi(repo, "submodule.active");
250         if (sl) {
251                 struct pathspec ps;
252                 struct argv_array args = ARGV_ARRAY_INIT;
253                 const struct string_list_item *item;
254
255                 for_each_string_list_item(item, sl) {
256                         argv_array_push(&args, item->string);
257                 }
258
259                 parse_pathspec(&ps, 0, 0, NULL, args.argv);
260                 ret = match_pathspec(&ps, path, strlen(path), 0, NULL, 1);
261
262                 argv_array_clear(&args);
263                 clear_pathspec(&ps);
264                 return ret;
265         }
266
267         /* fallback to checking if the URL is set */
268         key = xstrfmt("submodule.%s.url", module->name);
269         ret = !repo_config_get_string(repo, key, &value);
270
271         free(value);
272         free(key);
273         return ret;
274 }
275
276 int is_submodule_populated_gently(const char *path, int *return_error_code)
277 {
278         int ret = 0;
279         char *gitdir = xstrfmt("%s/.git", path);
280
281         if (resolve_gitdir_gently(gitdir, return_error_code))
282                 ret = 1;
283
284         free(gitdir);
285         return ret;
286 }
287
288 /*
289  * Dies if the provided 'prefix' corresponds to an unpopulated submodule
290  */
291 void die_in_unpopulated_submodule(const struct index_state *istate,
292                                   const char *prefix)
293 {
294         int i, prefixlen;
295
296         if (!prefix)
297                 return;
298
299         prefixlen = strlen(prefix);
300
301         for (i = 0; i < istate->cache_nr; i++) {
302                 struct cache_entry *ce = istate->cache[i];
303                 int ce_len = ce_namelen(ce);
304
305                 if (!S_ISGITLINK(ce->ce_mode))
306                         continue;
307                 if (prefixlen <= ce_len)
308                         continue;
309                 if (strncmp(ce->name, prefix, ce_len))
310                         continue;
311                 if (prefix[ce_len] != '/')
312                         continue;
313
314                 die(_("in unpopulated submodule '%s'"), ce->name);
315         }
316 }
317
318 /*
319  * Dies if any paths in the provided pathspec descends into a submodule
320  */
321 void die_path_inside_submodule(const struct index_state *istate,
322                                const struct pathspec *ps)
323 {
324         int i, j;
325
326         for (i = 0; i < istate->cache_nr; i++) {
327                 struct cache_entry *ce = istate->cache[i];
328                 int ce_len = ce_namelen(ce);
329
330                 if (!S_ISGITLINK(ce->ce_mode))
331                         continue;
332
333                 for (j = 0; j < ps->nr ; j++) {
334                         const struct pathspec_item *item = &ps->items[j];
335
336                         if (item->len <= ce_len)
337                                 continue;
338                         if (item->match[ce_len] != '/')
339                                 continue;
340                         if (strncmp(ce->name, item->match, ce_len))
341                                 continue;
342                         if (item->len == ce_len + 1)
343                                 continue;
344
345                         die(_("Pathspec '%s' is in submodule '%.*s'"),
346                             item->original, ce_len, ce->name);
347                 }
348         }
349 }
350
351 enum submodule_update_type parse_submodule_update_type(const char *value)
352 {
353         if (!strcmp(value, "none"))
354                 return SM_UPDATE_NONE;
355         else if (!strcmp(value, "checkout"))
356                 return SM_UPDATE_CHECKOUT;
357         else if (!strcmp(value, "rebase"))
358                 return SM_UPDATE_REBASE;
359         else if (!strcmp(value, "merge"))
360                 return SM_UPDATE_MERGE;
361         else if (*value == '!')
362                 return SM_UPDATE_COMMAND;
363         else
364                 return SM_UPDATE_UNSPECIFIED;
365 }
366
367 int parse_submodule_update_strategy(const char *value,
368                 struct submodule_update_strategy *dst)
369 {
370         enum submodule_update_type type;
371
372         free((void*)dst->command);
373         dst->command = NULL;
374
375         type = parse_submodule_update_type(value);
376         if (type == SM_UPDATE_UNSPECIFIED)
377                 return -1;
378
379         dst->type = type;
380         if (type == SM_UPDATE_COMMAND)
381                 dst->command = xstrdup(value + 1);
382
383         return 0;
384 }
385
386 const char *submodule_strategy_to_string(const struct submodule_update_strategy *s)
387 {
388         struct strbuf sb = STRBUF_INIT;
389         switch (s->type) {
390         case SM_UPDATE_CHECKOUT:
391                 return "checkout";
392         case SM_UPDATE_MERGE:
393                 return "merge";
394         case SM_UPDATE_REBASE:
395                 return "rebase";
396         case SM_UPDATE_NONE:
397                 return "none";
398         case SM_UPDATE_UNSPECIFIED:
399                 return NULL;
400         case SM_UPDATE_COMMAND:
401                 strbuf_addf(&sb, "!%s", s->command);
402                 return strbuf_detach(&sb, NULL);
403         }
404         return NULL;
405 }
406
407 void handle_ignore_submodules_arg(struct diff_options *diffopt,
408                                   const char *arg)
409 {
410         diffopt->flags.ignore_submodules = 0;
411         diffopt->flags.ignore_untracked_in_submodules = 0;
412         diffopt->flags.ignore_dirty_submodules = 0;
413
414         if (!strcmp(arg, "all"))
415                 diffopt->flags.ignore_submodules = 1;
416         else if (!strcmp(arg, "untracked"))
417                 diffopt->flags.ignore_untracked_in_submodules = 1;
418         else if (!strcmp(arg, "dirty"))
419                 diffopt->flags.ignore_dirty_submodules = 1;
420         else if (strcmp(arg, "none"))
421                 die("bad --ignore-submodules argument: %s", arg);
422 }
423
424 static int prepare_submodule_summary(struct rev_info *rev, const char *path,
425                 struct commit *left, struct commit *right,
426                 struct commit_list *merge_bases)
427 {
428         struct commit_list *list;
429
430         init_revisions(rev, NULL);
431         setup_revisions(0, NULL, rev, NULL);
432         rev->left_right = 1;
433         rev->first_parent_only = 1;
434         left->object.flags |= SYMMETRIC_LEFT;
435         add_pending_object(rev, &left->object, path);
436         add_pending_object(rev, &right->object, path);
437         for (list = merge_bases; list; list = list->next) {
438                 list->item->object.flags |= UNINTERESTING;
439                 add_pending_object(rev, &list->item->object,
440                         oid_to_hex(&list->item->object.oid));
441         }
442         return prepare_revision_walk(rev);
443 }
444
445 static void print_submodule_summary(struct rev_info *rev, struct diff_options *o)
446 {
447         static const char format[] = "  %m %s";
448         struct strbuf sb = STRBUF_INIT;
449         struct commit *commit;
450
451         while ((commit = get_revision(rev))) {
452                 struct pretty_print_context ctx = {0};
453                 ctx.date_mode = rev->date_mode;
454                 ctx.output_encoding = get_log_output_encoding();
455                 strbuf_setlen(&sb, 0);
456                 format_commit_message(commit, format, &sb, &ctx);
457                 strbuf_addch(&sb, '\n');
458                 if (commit->object.flags & SYMMETRIC_LEFT)
459                         diff_emit_submodule_del(o, sb.buf);
460                 else
461                         diff_emit_submodule_add(o, sb.buf);
462         }
463         strbuf_release(&sb);
464 }
465
466 static void prepare_submodule_repo_env_no_git_dir(struct argv_array *out)
467 {
468         const char * const *var;
469
470         for (var = local_repo_env; *var; var++) {
471                 if (strcmp(*var, CONFIG_DATA_ENVIRONMENT))
472                         argv_array_push(out, *var);
473         }
474 }
475
476 void prepare_submodule_repo_env(struct argv_array *out)
477 {
478         prepare_submodule_repo_env_no_git_dir(out);
479         argv_array_pushf(out, "%s=%s", GIT_DIR_ENVIRONMENT,
480                          DEFAULT_GIT_DIR_ENVIRONMENT);
481 }
482
483 /* Helper function to display the submodule header line prior to the full
484  * summary output. If it can locate the submodule objects directory it will
485  * attempt to lookup both the left and right commits and put them into the
486  * left and right pointers.
487  */
488 static void show_submodule_header(struct diff_options *o, const char *path,
489                 struct object_id *one, struct object_id *two,
490                 unsigned dirty_submodule,
491                 struct commit **left, struct commit **right,
492                 struct commit_list **merge_bases)
493 {
494         const char *message = NULL;
495         struct strbuf sb = STRBUF_INIT;
496         int fast_forward = 0, fast_backward = 0;
497
498         if (dirty_submodule & DIRTY_SUBMODULE_UNTRACKED)
499                 diff_emit_submodule_untracked(o, path);
500
501         if (dirty_submodule & DIRTY_SUBMODULE_MODIFIED)
502                 diff_emit_submodule_modified(o, path);
503
504         if (is_null_oid(one))
505                 message = "(new submodule)";
506         else if (is_null_oid(two))
507                 message = "(submodule deleted)";
508
509         if (add_submodule_odb(path)) {
510                 if (!message)
511                         message = "(commits not present)";
512                 goto output_header;
513         }
514
515         /*
516          * Attempt to lookup the commit references, and determine if this is
517          * a fast forward or fast backwards update.
518          */
519         *left = lookup_commit_reference(one);
520         *right = lookup_commit_reference(two);
521
522         /*
523          * Warn about missing commits in the submodule project, but only if
524          * they aren't null.
525          */
526         if ((!is_null_oid(one) && !*left) ||
527              (!is_null_oid(two) && !*right))
528                 message = "(commits not present)";
529
530         *merge_bases = get_merge_bases(*left, *right);
531         if (*merge_bases) {
532                 if ((*merge_bases)->item == *left)
533                         fast_forward = 1;
534                 else if ((*merge_bases)->item == *right)
535                         fast_backward = 1;
536         }
537
538         if (!oidcmp(one, two)) {
539                 strbuf_release(&sb);
540                 return;
541         }
542
543 output_header:
544         strbuf_addf(&sb, "Submodule %s ", path);
545         strbuf_add_unique_abbrev(&sb, one, DEFAULT_ABBREV);
546         strbuf_addstr(&sb, (fast_backward || fast_forward) ? ".." : "...");
547         strbuf_add_unique_abbrev(&sb, two, DEFAULT_ABBREV);
548         if (message)
549                 strbuf_addf(&sb, " %s\n", message);
550         else
551                 strbuf_addf(&sb, "%s:\n", fast_backward ? " (rewind)" : "");
552         diff_emit_submodule_header(o, sb.buf);
553
554         strbuf_release(&sb);
555 }
556
557 void show_submodule_summary(struct diff_options *o, const char *path,
558                 struct object_id *one, struct object_id *two,
559                 unsigned dirty_submodule)
560 {
561         struct rev_info rev;
562         struct commit *left = NULL, *right = NULL;
563         struct commit_list *merge_bases = NULL;
564
565         show_submodule_header(o, path, one, two, dirty_submodule,
566                               &left, &right, &merge_bases);
567
568         /*
569          * If we don't have both a left and a right pointer, there is no
570          * reason to try and display a summary. The header line should contain
571          * all the information the user needs.
572          */
573         if (!left || !right)
574                 goto out;
575
576         /* Treat revision walker failure the same as missing commits */
577         if (prepare_submodule_summary(&rev, path, left, right, merge_bases)) {
578                 diff_emit_submodule_error(o, "(revision walker failed)\n");
579                 goto out;
580         }
581
582         print_submodule_summary(&rev, o);
583
584 out:
585         if (merge_bases)
586                 free_commit_list(merge_bases);
587         clear_commit_marks(left, ~0);
588         clear_commit_marks(right, ~0);
589 }
590
591 void show_submodule_inline_diff(struct diff_options *o, const char *path,
592                 struct object_id *one, struct object_id *two,
593                 unsigned dirty_submodule)
594 {
595         const struct object_id *old_oid = the_hash_algo->empty_tree, *new_oid = the_hash_algo->empty_tree;
596         struct commit *left = NULL, *right = NULL;
597         struct commit_list *merge_bases = NULL;
598         struct child_process cp = CHILD_PROCESS_INIT;
599         struct strbuf sb = STRBUF_INIT;
600
601         show_submodule_header(o, path, one, two, dirty_submodule,
602                               &left, &right, &merge_bases);
603
604         /* We need a valid left and right commit to display a difference */
605         if (!(left || is_null_oid(one)) ||
606             !(right || is_null_oid(two)))
607                 goto done;
608
609         if (left)
610                 old_oid = one;
611         if (right)
612                 new_oid = two;
613
614         cp.git_cmd = 1;
615         cp.dir = path;
616         cp.out = -1;
617         cp.no_stdin = 1;
618
619         /* TODO: other options may need to be passed here. */
620         argv_array_pushl(&cp.args, "diff", "--submodule=diff", NULL);
621         argv_array_pushf(&cp.args, "--color=%s", want_color(o->use_color) ?
622                          "always" : "never");
623
624         if (o->flags.reverse_diff) {
625                 argv_array_pushf(&cp.args, "--src-prefix=%s%s/",
626                                  o->b_prefix, path);
627                 argv_array_pushf(&cp.args, "--dst-prefix=%s%s/",
628                                  o->a_prefix, path);
629         } else {
630                 argv_array_pushf(&cp.args, "--src-prefix=%s%s/",
631                                  o->a_prefix, path);
632                 argv_array_pushf(&cp.args, "--dst-prefix=%s%s/",
633                                  o->b_prefix, path);
634         }
635         argv_array_push(&cp.args, oid_to_hex(old_oid));
636         /*
637          * If the submodule has modified content, we will diff against the
638          * work tree, under the assumption that the user has asked for the
639          * diff format and wishes to actually see all differences even if they
640          * haven't yet been committed to the submodule yet.
641          */
642         if (!(dirty_submodule & DIRTY_SUBMODULE_MODIFIED))
643                 argv_array_push(&cp.args, oid_to_hex(new_oid));
644
645         prepare_submodule_repo_env(&cp.env_array);
646         if (start_command(&cp))
647                 diff_emit_submodule_error(o, "(diff failed)\n");
648
649         while (strbuf_getwholeline_fd(&sb, cp.out, '\n') != EOF)
650                 diff_emit_submodule_pipethrough(o, sb.buf, sb.len);
651
652         if (finish_command(&cp))
653                 diff_emit_submodule_error(o, "(diff failed)\n");
654
655 done:
656         strbuf_release(&sb);
657         if (merge_bases)
658                 free_commit_list(merge_bases);
659         if (left)
660                 clear_commit_marks(left, ~0);
661         if (right)
662                 clear_commit_marks(right, ~0);
663 }
664
665 int should_update_submodules(void)
666 {
667         return config_update_recurse_submodules == RECURSE_SUBMODULES_ON;
668 }
669
670 const struct submodule *submodule_from_ce(const struct cache_entry *ce)
671 {
672         if (!S_ISGITLINK(ce->ce_mode))
673                 return NULL;
674
675         if (!should_update_submodules())
676                 return NULL;
677
678         return submodule_from_path(the_repository, &null_oid, ce->name);
679 }
680
681 static struct oid_array *submodule_commits(struct string_list *submodules,
682                                            const char *name)
683 {
684         struct string_list_item *item;
685
686         item = string_list_insert(submodules, name);
687         if (item->util)
688                 return (struct oid_array *) item->util;
689
690         /* NEEDSWORK: should we have oid_array_init()? */
691         item->util = xcalloc(1, sizeof(struct oid_array));
692         return (struct oid_array *) item->util;
693 }
694
695 struct collect_changed_submodules_cb_data {
696         struct string_list *changed;
697         const struct object_id *commit_oid;
698 };
699
700 /*
701  * this would normally be two functions: default_name_from_path() and
702  * path_from_default_name(). Since the default name is the same as
703  * the submodule path we can get away with just one function which only
704  * checks whether there is a submodule in the working directory at that
705  * location.
706  */
707 static const char *default_name_or_path(const char *path_or_name)
708 {
709         int error_code;
710
711         if (!is_submodule_populated_gently(path_or_name, &error_code))
712                 return NULL;
713
714         return path_or_name;
715 }
716
717 static void collect_changed_submodules_cb(struct diff_queue_struct *q,
718                                           struct diff_options *options,
719                                           void *data)
720 {
721         struct collect_changed_submodules_cb_data *me = data;
722         struct string_list *changed = me->changed;
723         const struct object_id *commit_oid = me->commit_oid;
724         int i;
725
726         for (i = 0; i < q->nr; i++) {
727                 struct diff_filepair *p = q->queue[i];
728                 struct oid_array *commits;
729                 const struct submodule *submodule;
730                 const char *name;
731
732                 if (!S_ISGITLINK(p->two->mode))
733                         continue;
734
735                 submodule = submodule_from_path(the_repository,
736                                                 commit_oid, p->two->path);
737                 if (submodule)
738                         name = submodule->name;
739                 else {
740                         name = default_name_or_path(p->two->path);
741                         /* make sure name does not collide with existing one */
742                         submodule = submodule_from_name(the_repository, commit_oid, name);
743                         if (submodule) {
744                                 warning("Submodule in commit %s at path: "
745                                         "'%s' collides with a submodule named "
746                                         "the same. Skipping it.",
747                                         oid_to_hex(commit_oid), name);
748                                 name = NULL;
749                         }
750                 }
751
752                 if (!name)
753                         continue;
754
755                 commits = submodule_commits(changed, name);
756                 oid_array_append(commits, &p->two->oid);
757         }
758 }
759
760 /*
761  * Collect the paths of submodules in 'changed' which have changed based on
762  * the revisions as specified in 'argv'.  Each entry in 'changed' will also
763  * have a corresponding 'struct oid_array' (in the 'util' field) which lists
764  * what the submodule pointers were updated to during the change.
765  */
766 static void collect_changed_submodules(struct string_list *changed,
767                                        struct argv_array *argv)
768 {
769         struct rev_info rev;
770         const struct commit *commit;
771
772         init_revisions(&rev, NULL);
773         setup_revisions(argv->argc, argv->argv, &rev, NULL);
774         if (prepare_revision_walk(&rev))
775                 die("revision walk setup failed");
776
777         while ((commit = get_revision(&rev))) {
778                 struct rev_info diff_rev;
779                 struct collect_changed_submodules_cb_data data;
780                 data.changed = changed;
781                 data.commit_oid = &commit->object.oid;
782
783                 init_revisions(&diff_rev, NULL);
784                 diff_rev.diffopt.output_format |= DIFF_FORMAT_CALLBACK;
785                 diff_rev.diffopt.format_callback = collect_changed_submodules_cb;
786                 diff_rev.diffopt.format_callback_data = &data;
787                 diff_tree_combined_merge(commit, 1, &diff_rev);
788         }
789
790         reset_revision_walk();
791 }
792
793 static void free_submodules_oids(struct string_list *submodules)
794 {
795         struct string_list_item *item;
796         for_each_string_list_item(item, submodules)
797                 oid_array_clear((struct oid_array *) item->util);
798         string_list_clear(submodules, 1);
799 }
800
801 static int has_remote(const char *refname, const struct object_id *oid,
802                       int flags, void *cb_data)
803 {
804         return 1;
805 }
806
807 static int append_oid_to_argv(const struct object_id *oid, void *data)
808 {
809         struct argv_array *argv = data;
810         argv_array_push(argv, oid_to_hex(oid));
811         return 0;
812 }
813
814 struct has_commit_data {
815         int result;
816         const char *path;
817 };
818
819 static int check_has_commit(const struct object_id *oid, void *data)
820 {
821         struct has_commit_data *cb = data;
822
823         enum object_type type = oid_object_info(oid, NULL);
824
825         switch (type) {
826         case OBJ_COMMIT:
827                 return 0;
828         case OBJ_BAD:
829                 /*
830                  * Object is missing or invalid. If invalid, an error message
831                  * has already been printed.
832                  */
833                 cb->result = 0;
834                 return 0;
835         default:
836                 die(_("submodule entry '%s' (%s) is a %s, not a commit"),
837                     cb->path, oid_to_hex(oid), type_name(type));
838         }
839 }
840
841 static int submodule_has_commits(const char *path, struct oid_array *commits)
842 {
843         struct has_commit_data has_commit = { 1, path };
844
845         /*
846          * Perform a cheap, but incorrect check for the existence of 'commits'.
847          * This is done by adding the submodule's object store to the in-core
848          * object store, and then querying for each commit's existence.  If we
849          * do not have the commit object anywhere, there is no chance we have
850          * it in the object store of the correct submodule and have it
851          * reachable from a ref, so we can fail early without spawning rev-list
852          * which is expensive.
853          */
854         if (add_submodule_odb(path))
855                 return 0;
856
857         oid_array_for_each_unique(commits, check_has_commit, &has_commit);
858
859         if (has_commit.result) {
860                 /*
861                  * Even if the submodule is checked out and the commit is
862                  * present, make sure it exists in the submodule's object store
863                  * and that it is reachable from a ref.
864                  */
865                 struct child_process cp = CHILD_PROCESS_INIT;
866                 struct strbuf out = STRBUF_INIT;
867
868                 argv_array_pushl(&cp.args, "rev-list", "-n", "1", NULL);
869                 oid_array_for_each_unique(commits, append_oid_to_argv, &cp.args);
870                 argv_array_pushl(&cp.args, "--not", "--all", NULL);
871
872                 prepare_submodule_repo_env(&cp.env_array);
873                 cp.git_cmd = 1;
874                 cp.no_stdin = 1;
875                 cp.dir = path;
876
877                 if (capture_command(&cp, &out, GIT_MAX_HEXSZ + 1) || out.len)
878                         has_commit.result = 0;
879
880                 strbuf_release(&out);
881         }
882
883         return has_commit.result;
884 }
885
886 static int submodule_needs_pushing(const char *path, struct oid_array *commits)
887 {
888         if (!submodule_has_commits(path, commits))
889                 /*
890                  * NOTE: We do consider it safe to return "no" here. The
891                  * correct answer would be "We do not know" instead of
892                  * "No push needed", but it is quite hard to change
893                  * the submodule pointer without having the submodule
894                  * around. If a user did however change the submodules
895                  * without having the submodule around, this indicates
896                  * an expert who knows what they are doing or a
897                  * maintainer integrating work from other people. In
898                  * both cases it should be safe to skip this check.
899                  */
900                 return 0;
901
902         if (for_each_remote_ref_submodule(path, has_remote, NULL) > 0) {
903                 struct child_process cp = CHILD_PROCESS_INIT;
904                 struct strbuf buf = STRBUF_INIT;
905                 int needs_pushing = 0;
906
907                 argv_array_push(&cp.args, "rev-list");
908                 oid_array_for_each_unique(commits, append_oid_to_argv, &cp.args);
909                 argv_array_pushl(&cp.args, "--not", "--remotes", "-n", "1" , NULL);
910
911                 prepare_submodule_repo_env(&cp.env_array);
912                 cp.git_cmd = 1;
913                 cp.no_stdin = 1;
914                 cp.out = -1;
915                 cp.dir = path;
916                 if (start_command(&cp))
917                         die("Could not run 'git rev-list <commits> --not --remotes -n 1' command in submodule %s",
918                                         path);
919                 if (strbuf_read(&buf, cp.out, 41))
920                         needs_pushing = 1;
921                 finish_command(&cp);
922                 close(cp.out);
923                 strbuf_release(&buf);
924                 return needs_pushing;
925         }
926
927         return 0;
928 }
929
930 int find_unpushed_submodules(struct oid_array *commits,
931                 const char *remotes_name, struct string_list *needs_pushing)
932 {
933         struct string_list submodules = STRING_LIST_INIT_DUP;
934         struct string_list_item *name;
935         struct argv_array argv = ARGV_ARRAY_INIT;
936
937         /* argv.argv[0] will be ignored by setup_revisions */
938         argv_array_push(&argv, "find_unpushed_submodules");
939         oid_array_for_each_unique(commits, append_oid_to_argv, &argv);
940         argv_array_push(&argv, "--not");
941         argv_array_pushf(&argv, "--remotes=%s", remotes_name);
942
943         collect_changed_submodules(&submodules, &argv);
944
945         for_each_string_list_item(name, &submodules) {
946                 struct oid_array *commits = name->util;
947                 const struct submodule *submodule;
948                 const char *path = NULL;
949
950                 submodule = submodule_from_name(the_repository, &null_oid, name->string);
951                 if (submodule)
952                         path = submodule->path;
953                 else
954                         path = default_name_or_path(name->string);
955
956                 if (!path)
957                         continue;
958
959                 if (submodule_needs_pushing(path, commits))
960                         string_list_insert(needs_pushing, path);
961         }
962
963         free_submodules_oids(&submodules);
964         argv_array_clear(&argv);
965
966         return needs_pushing->nr;
967 }
968
969 static int push_submodule(const char *path,
970                           const struct remote *remote,
971                           const char **refspec, int refspec_nr,
972                           const struct string_list *push_options,
973                           int dry_run)
974 {
975         if (add_submodule_odb(path))
976                 return 1;
977
978         if (for_each_remote_ref_submodule(path, has_remote, NULL) > 0) {
979                 struct child_process cp = CHILD_PROCESS_INIT;
980                 argv_array_push(&cp.args, "push");
981                 if (dry_run)
982                         argv_array_push(&cp.args, "--dry-run");
983
984                 if (push_options && push_options->nr) {
985                         const struct string_list_item *item;
986                         for_each_string_list_item(item, push_options)
987                                 argv_array_pushf(&cp.args, "--push-option=%s",
988                                                  item->string);
989                 }
990
991                 if (remote->origin != REMOTE_UNCONFIGURED) {
992                         int i;
993                         argv_array_push(&cp.args, remote->name);
994                         for (i = 0; i < refspec_nr; i++)
995                                 argv_array_push(&cp.args, refspec[i]);
996                 }
997
998                 prepare_submodule_repo_env(&cp.env_array);
999                 cp.git_cmd = 1;
1000                 cp.no_stdin = 1;
1001                 cp.dir = path;
1002                 if (run_command(&cp))
1003                         return 0;
1004                 close(cp.out);
1005         }
1006
1007         return 1;
1008 }
1009
1010 /*
1011  * Perform a check in the submodule to see if the remote and refspec work.
1012  * Die if the submodule can't be pushed.
1013  */
1014 static void submodule_push_check(const char *path, const char *head,
1015                                  const struct remote *remote,
1016                                  const char **refspec, int refspec_nr)
1017 {
1018         struct child_process cp = CHILD_PROCESS_INIT;
1019         int i;
1020
1021         argv_array_push(&cp.args, "submodule--helper");
1022         argv_array_push(&cp.args, "push-check");
1023         argv_array_push(&cp.args, head);
1024         argv_array_push(&cp.args, remote->name);
1025
1026         for (i = 0; i < refspec_nr; i++)
1027                 argv_array_push(&cp.args, refspec[i]);
1028
1029         prepare_submodule_repo_env(&cp.env_array);
1030         cp.git_cmd = 1;
1031         cp.no_stdin = 1;
1032         cp.no_stdout = 1;
1033         cp.dir = path;
1034
1035         /*
1036          * Simply indicate if 'submodule--helper push-check' failed.
1037          * More detailed error information will be provided by the
1038          * child process.
1039          */
1040         if (run_command(&cp))
1041                 die("process for submodule '%s' failed", path);
1042 }
1043
1044 int push_unpushed_submodules(struct oid_array *commits,
1045                              const struct remote *remote,
1046                              const char **refspec, int refspec_nr,
1047                              const struct string_list *push_options,
1048                              int dry_run)
1049 {
1050         int i, ret = 1;
1051         struct string_list needs_pushing = STRING_LIST_INIT_DUP;
1052
1053         if (!find_unpushed_submodules(commits, remote->name, &needs_pushing))
1054                 return 1;
1055
1056         /*
1057          * Verify that the remote and refspec can be propagated to all
1058          * submodules.  This check can be skipped if the remote and refspec
1059          * won't be propagated due to the remote being unconfigured (e.g. a URL
1060          * instead of a remote name).
1061          */
1062         if (remote->origin != REMOTE_UNCONFIGURED) {
1063                 char *head;
1064                 struct object_id head_oid;
1065
1066                 head = resolve_refdup("HEAD", 0, &head_oid, NULL);
1067                 if (!head)
1068                         die(_("Failed to resolve HEAD as a valid ref."));
1069
1070                 for (i = 0; i < needs_pushing.nr; i++)
1071                         submodule_push_check(needs_pushing.items[i].string,
1072                                              head, remote,
1073                                              refspec, refspec_nr);
1074                 free(head);
1075         }
1076
1077         /* Actually push the submodules */
1078         for (i = 0; i < needs_pushing.nr; i++) {
1079                 const char *path = needs_pushing.items[i].string;
1080                 fprintf(stderr, "Pushing submodule '%s'\n", path);
1081                 if (!push_submodule(path, remote, refspec, refspec_nr,
1082                                     push_options, dry_run)) {
1083                         fprintf(stderr, "Unable to push submodule '%s'\n", path);
1084                         ret = 0;
1085                 }
1086         }
1087
1088         string_list_clear(&needs_pushing, 0);
1089
1090         return ret;
1091 }
1092
1093 static int append_oid_to_array(const char *ref, const struct object_id *oid,
1094                                int flags, void *data)
1095 {
1096         struct oid_array *array = data;
1097         oid_array_append(array, oid);
1098         return 0;
1099 }
1100
1101 void check_for_new_submodule_commits(struct object_id *oid)
1102 {
1103         if (!initialized_fetch_ref_tips) {
1104                 for_each_ref(append_oid_to_array, &ref_tips_before_fetch);
1105                 initialized_fetch_ref_tips = 1;
1106         }
1107
1108         oid_array_append(&ref_tips_after_fetch, oid);
1109 }
1110
1111 static void calculate_changed_submodule_paths(void)
1112 {
1113         struct argv_array argv = ARGV_ARRAY_INIT;
1114         struct string_list changed_submodules = STRING_LIST_INIT_DUP;
1115         const struct string_list_item *name;
1116
1117         /* No need to check if there are no submodules configured */
1118         if (!submodule_from_path(the_repository, NULL, NULL))
1119                 return;
1120
1121         argv_array_push(&argv, "--"); /* argv[0] program name */
1122         oid_array_for_each_unique(&ref_tips_after_fetch,
1123                                    append_oid_to_argv, &argv);
1124         argv_array_push(&argv, "--not");
1125         oid_array_for_each_unique(&ref_tips_before_fetch,
1126                                    append_oid_to_argv, &argv);
1127
1128         /*
1129          * Collect all submodules (whether checked out or not) for which new
1130          * commits have been recorded upstream in "changed_submodule_names".
1131          */
1132         collect_changed_submodules(&changed_submodules, &argv);
1133
1134         for_each_string_list_item(name, &changed_submodules) {
1135                 struct oid_array *commits = name->util;
1136                 const struct submodule *submodule;
1137                 const char *path = NULL;
1138
1139                 submodule = submodule_from_name(the_repository, &null_oid, name->string);
1140                 if (submodule)
1141                         path = submodule->path;
1142                 else
1143                         path = default_name_or_path(name->string);
1144
1145                 if (!path)
1146                         continue;
1147
1148                 if (!submodule_has_commits(path, commits))
1149                         string_list_append(&changed_submodule_names, name->string);
1150         }
1151
1152         free_submodules_oids(&changed_submodules);
1153         argv_array_clear(&argv);
1154         oid_array_clear(&ref_tips_before_fetch);
1155         oid_array_clear(&ref_tips_after_fetch);
1156         initialized_fetch_ref_tips = 0;
1157 }
1158
1159 int submodule_touches_in_range(struct object_id *excl_oid,
1160                                struct object_id *incl_oid)
1161 {
1162         struct string_list subs = STRING_LIST_INIT_DUP;
1163         struct argv_array args = ARGV_ARRAY_INIT;
1164         int ret;
1165
1166         /* No need to check if there are no submodules configured */
1167         if (!submodule_from_path(the_repository, NULL, NULL))
1168                 return 0;
1169
1170         argv_array_push(&args, "--"); /* args[0] program name */
1171         argv_array_push(&args, oid_to_hex(incl_oid));
1172         argv_array_push(&args, "--not");
1173         argv_array_push(&args, oid_to_hex(excl_oid));
1174
1175         collect_changed_submodules(&subs, &args);
1176         ret = subs.nr;
1177
1178         argv_array_clear(&args);
1179
1180         free_submodules_oids(&subs);
1181         return ret;
1182 }
1183
1184 struct submodule_parallel_fetch {
1185         int count;
1186         struct argv_array args;
1187         struct repository *r;
1188         const char *prefix;
1189         int command_line_option;
1190         int default_option;
1191         int quiet;
1192         int result;
1193 };
1194 #define SPF_INIT {0, ARGV_ARRAY_INIT, NULL, NULL, 0, 0, 0, 0}
1195
1196 static int get_fetch_recurse_config(const struct submodule *submodule,
1197                                     struct submodule_parallel_fetch *spf)
1198 {
1199         if (spf->command_line_option != RECURSE_SUBMODULES_DEFAULT)
1200                 return spf->command_line_option;
1201
1202         if (submodule) {
1203                 char *key;
1204                 const char *value;
1205
1206                 int fetch_recurse = submodule->fetch_recurse;
1207                 key = xstrfmt("submodule.%s.fetchRecurseSubmodules", submodule->name);
1208                 if (!repo_config_get_string_const(spf->r, key, &value)) {
1209                         fetch_recurse = parse_fetch_recurse_submodules_arg(key, value);
1210                 }
1211                 free(key);
1212
1213                 if (fetch_recurse != RECURSE_SUBMODULES_NONE)
1214                         /* local config overrules everything except commandline */
1215                         return fetch_recurse;
1216         }
1217
1218         return spf->default_option;
1219 }
1220
1221 static int get_next_submodule(struct child_process *cp,
1222                               struct strbuf *err, void *data, void **task_cb)
1223 {
1224         int ret = 0;
1225         struct submodule_parallel_fetch *spf = data;
1226
1227         for (; spf->count < spf->r->index->cache_nr; spf->count++) {
1228                 struct strbuf submodule_path = STRBUF_INIT;
1229                 struct strbuf submodule_git_dir = STRBUF_INIT;
1230                 struct strbuf submodule_prefix = STRBUF_INIT;
1231                 const struct cache_entry *ce = spf->r->index->cache[spf->count];
1232                 const char *git_dir, *default_argv;
1233                 const struct submodule *submodule;
1234                 struct submodule default_submodule = SUBMODULE_INIT;
1235
1236                 if (!S_ISGITLINK(ce->ce_mode))
1237                         continue;
1238
1239                 submodule = submodule_from_path(spf->r, &null_oid, ce->name);
1240                 if (!submodule) {
1241                         const char *name = default_name_or_path(ce->name);
1242                         if (name) {
1243                                 default_submodule.path = default_submodule.name = name;
1244                                 submodule = &default_submodule;
1245                         }
1246                 }
1247
1248                 switch (get_fetch_recurse_config(submodule, spf))
1249                 {
1250                 default:
1251                 case RECURSE_SUBMODULES_DEFAULT:
1252                 case RECURSE_SUBMODULES_ON_DEMAND:
1253                         if (!submodule || !unsorted_string_list_lookup(&changed_submodule_names,
1254                                                          submodule->name))
1255                                 continue;
1256                         default_argv = "on-demand";
1257                         break;
1258                 case RECURSE_SUBMODULES_ON:
1259                         default_argv = "yes";
1260                         break;
1261                 case RECURSE_SUBMODULES_OFF:
1262                         continue;
1263                 }
1264
1265                 strbuf_repo_worktree_path(&submodule_path, spf->r, "%s", ce->name);
1266                 strbuf_addf(&submodule_git_dir, "%s/.git", submodule_path.buf);
1267                 strbuf_addf(&submodule_prefix, "%s%s/", spf->prefix, ce->name);
1268                 git_dir = read_gitfile(submodule_git_dir.buf);
1269                 if (!git_dir)
1270                         git_dir = submodule_git_dir.buf;
1271                 if (is_directory(git_dir)) {
1272                         child_process_init(cp);
1273                         cp->dir = strbuf_detach(&submodule_path, NULL);
1274                         prepare_submodule_repo_env(&cp->env_array);
1275                         cp->git_cmd = 1;
1276                         if (!spf->quiet)
1277                                 strbuf_addf(err, "Fetching submodule %s%s\n",
1278                                             spf->prefix, ce->name);
1279                         argv_array_init(&cp->args);
1280                         argv_array_pushv(&cp->args, spf->args.argv);
1281                         argv_array_push(&cp->args, default_argv);
1282                         argv_array_push(&cp->args, "--submodule-prefix");
1283                         argv_array_push(&cp->args, submodule_prefix.buf);
1284                         ret = 1;
1285                 }
1286                 strbuf_release(&submodule_path);
1287                 strbuf_release(&submodule_git_dir);
1288                 strbuf_release(&submodule_prefix);
1289                 if (ret) {
1290                         spf->count++;
1291                         return 1;
1292                 }
1293         }
1294         return 0;
1295 }
1296
1297 static int fetch_start_failure(struct strbuf *err,
1298                                void *cb, void *task_cb)
1299 {
1300         struct submodule_parallel_fetch *spf = cb;
1301
1302         spf->result = 1;
1303
1304         return 0;
1305 }
1306
1307 static int fetch_finish(int retvalue, struct strbuf *err,
1308                         void *cb, void *task_cb)
1309 {
1310         struct submodule_parallel_fetch *spf = cb;
1311
1312         if (retvalue)
1313                 spf->result = 1;
1314
1315         return 0;
1316 }
1317
1318 int fetch_populated_submodules(struct repository *r,
1319                                const struct argv_array *options,
1320                                const char *prefix, int command_line_option,
1321                                int default_option,
1322                                int quiet, int max_parallel_jobs)
1323 {
1324         int i;
1325         struct submodule_parallel_fetch spf = SPF_INIT;
1326
1327         spf.r = r;
1328         spf.command_line_option = command_line_option;
1329         spf.default_option = default_option;
1330         spf.quiet = quiet;
1331         spf.prefix = prefix;
1332
1333         if (!r->worktree)
1334                 goto out;
1335
1336         if (repo_read_index(r) < 0)
1337                 die("index file corrupt");
1338
1339         argv_array_push(&spf.args, "fetch");
1340         for (i = 0; i < options->argc; i++)
1341                 argv_array_push(&spf.args, options->argv[i]);
1342         argv_array_push(&spf.args, "--recurse-submodules-default");
1343         /* default value, "--submodule-prefix" and its value are added later */
1344
1345         calculate_changed_submodule_paths();
1346         run_processes_parallel(max_parallel_jobs,
1347                                get_next_submodule,
1348                                fetch_start_failure,
1349                                fetch_finish,
1350                                &spf);
1351
1352         argv_array_clear(&spf.args);
1353 out:
1354         string_list_clear(&changed_submodule_names, 1);
1355         return spf.result;
1356 }
1357
1358 unsigned is_submodule_modified(const char *path, int ignore_untracked)
1359 {
1360         struct child_process cp = CHILD_PROCESS_INIT;
1361         struct strbuf buf = STRBUF_INIT;
1362         FILE *fp;
1363         unsigned dirty_submodule = 0;
1364         const char *git_dir;
1365         int ignore_cp_exit_code = 0;
1366
1367         strbuf_addf(&buf, "%s/.git", path);
1368         git_dir = read_gitfile(buf.buf);
1369         if (!git_dir)
1370                 git_dir = buf.buf;
1371         if (!is_git_directory(git_dir)) {
1372                 if (is_directory(git_dir))
1373                         die(_("'%s' not recognized as a git repository"), git_dir);
1374                 strbuf_release(&buf);
1375                 /* The submodule is not checked out, so it is not modified */
1376                 return 0;
1377         }
1378         strbuf_reset(&buf);
1379
1380         argv_array_pushl(&cp.args, "status", "--porcelain=2", NULL);
1381         if (ignore_untracked)
1382                 argv_array_push(&cp.args, "-uno");
1383
1384         prepare_submodule_repo_env(&cp.env_array);
1385         cp.git_cmd = 1;
1386         cp.no_stdin = 1;
1387         cp.out = -1;
1388         cp.dir = path;
1389         if (start_command(&cp))
1390                 die("Could not run 'git status --porcelain=2' in submodule %s", path);
1391
1392         fp = xfdopen(cp.out, "r");
1393         while (strbuf_getwholeline(&buf, fp, '\n') != EOF) {
1394                 /* regular untracked files */
1395                 if (buf.buf[0] == '?')
1396                         dirty_submodule |= DIRTY_SUBMODULE_UNTRACKED;
1397
1398                 if (buf.buf[0] == 'u' ||
1399                     buf.buf[0] == '1' ||
1400                     buf.buf[0] == '2') {
1401                         /* T = line type, XY = status, SSSS = submodule state */
1402                         if (buf.len < strlen("T XY SSSS"))
1403                                 die("BUG: invalid status --porcelain=2 line %s",
1404                                     buf.buf);
1405
1406                         if (buf.buf[5] == 'S' && buf.buf[8] == 'U')
1407                                 /* nested untracked file */
1408                                 dirty_submodule |= DIRTY_SUBMODULE_UNTRACKED;
1409
1410                         if (buf.buf[0] == 'u' ||
1411                             buf.buf[0] == '2' ||
1412                             memcmp(buf.buf + 5, "S..U", 4))
1413                                 /* other change */
1414                                 dirty_submodule |= DIRTY_SUBMODULE_MODIFIED;
1415                 }
1416
1417                 if ((dirty_submodule & DIRTY_SUBMODULE_MODIFIED) &&
1418                     ((dirty_submodule & DIRTY_SUBMODULE_UNTRACKED) ||
1419                      ignore_untracked)) {
1420                         /*
1421                          * We're not interested in any further information from
1422                          * the child any more, neither output nor its exit code.
1423                          */
1424                         ignore_cp_exit_code = 1;
1425                         break;
1426                 }
1427         }
1428         fclose(fp);
1429
1430         if (finish_command(&cp) && !ignore_cp_exit_code)
1431                 die("'git status --porcelain=2' failed in submodule %s", path);
1432
1433         strbuf_release(&buf);
1434         return dirty_submodule;
1435 }
1436
1437 int submodule_uses_gitfile(const char *path)
1438 {
1439         struct child_process cp = CHILD_PROCESS_INIT;
1440         const char *argv[] = {
1441                 "submodule",
1442                 "foreach",
1443                 "--quiet",
1444                 "--recursive",
1445                 "test -f .git",
1446                 NULL,
1447         };
1448         struct strbuf buf = STRBUF_INIT;
1449         const char *git_dir;
1450
1451         strbuf_addf(&buf, "%s/.git", path);
1452         git_dir = read_gitfile(buf.buf);
1453         if (!git_dir) {
1454                 strbuf_release(&buf);
1455                 return 0;
1456         }
1457         strbuf_release(&buf);
1458
1459         /* Now test that all nested submodules use a gitfile too */
1460         cp.argv = argv;
1461         prepare_submodule_repo_env(&cp.env_array);
1462         cp.git_cmd = 1;
1463         cp.no_stdin = 1;
1464         cp.no_stderr = 1;
1465         cp.no_stdout = 1;
1466         cp.dir = path;
1467         if (run_command(&cp))
1468                 return 0;
1469
1470         return 1;
1471 }
1472
1473 /*
1474  * Check if it is a bad idea to remove a submodule, i.e. if we'd lose data
1475  * when doing so.
1476  *
1477  * Return 1 if we'd lose data, return 0 if the removal is fine,
1478  * and negative values for errors.
1479  */
1480 int bad_to_remove_submodule(const char *path, unsigned flags)
1481 {
1482         ssize_t len;
1483         struct child_process cp = CHILD_PROCESS_INIT;
1484         struct strbuf buf = STRBUF_INIT;
1485         int ret = 0;
1486
1487         if (!file_exists(path) || is_empty_dir(path))
1488                 return 0;
1489
1490         if (!submodule_uses_gitfile(path))
1491                 return 1;
1492
1493         argv_array_pushl(&cp.args, "status", "--porcelain",
1494                                    "--ignore-submodules=none", NULL);
1495
1496         if (flags & SUBMODULE_REMOVAL_IGNORE_UNTRACKED)
1497                 argv_array_push(&cp.args, "-uno");
1498         else
1499                 argv_array_push(&cp.args, "-uall");
1500
1501         if (!(flags & SUBMODULE_REMOVAL_IGNORE_IGNORED_UNTRACKED))
1502                 argv_array_push(&cp.args, "--ignored");
1503
1504         prepare_submodule_repo_env(&cp.env_array);
1505         cp.git_cmd = 1;
1506         cp.no_stdin = 1;
1507         cp.out = -1;
1508         cp.dir = path;
1509         if (start_command(&cp)) {
1510                 if (flags & SUBMODULE_REMOVAL_DIE_ON_ERROR)
1511                         die(_("could not start 'git status' in submodule '%s'"),
1512                                 path);
1513                 ret = -1;
1514                 goto out;
1515         }
1516
1517         len = strbuf_read(&buf, cp.out, 1024);
1518         if (len > 2)
1519                 ret = 1;
1520         close(cp.out);
1521
1522         if (finish_command(&cp)) {
1523                 if (flags & SUBMODULE_REMOVAL_DIE_ON_ERROR)
1524                         die(_("could not run 'git status' in submodule '%s'"),
1525                                 path);
1526                 ret = -1;
1527         }
1528 out:
1529         strbuf_release(&buf);
1530         return ret;
1531 }
1532
1533 static const char *get_super_prefix_or_empty(void)
1534 {
1535         const char *s = get_super_prefix();
1536         if (!s)
1537                 s = "";
1538         return s;
1539 }
1540
1541 static int submodule_has_dirty_index(const struct submodule *sub)
1542 {
1543         struct child_process cp = CHILD_PROCESS_INIT;
1544
1545         prepare_submodule_repo_env(&cp.env_array);
1546
1547         cp.git_cmd = 1;
1548         argv_array_pushl(&cp.args, "diff-index", "--quiet",
1549                                    "--cached", "HEAD", NULL);
1550         cp.no_stdin = 1;
1551         cp.no_stdout = 1;
1552         cp.dir = sub->path;
1553         if (start_command(&cp))
1554                 die("could not recurse into submodule '%s'", sub->path);
1555
1556         return finish_command(&cp);
1557 }
1558
1559 static void submodule_reset_index(const char *path)
1560 {
1561         struct child_process cp = CHILD_PROCESS_INIT;
1562         prepare_submodule_repo_env(&cp.env_array);
1563
1564         cp.git_cmd = 1;
1565         cp.no_stdin = 1;
1566         cp.dir = path;
1567
1568         argv_array_pushf(&cp.args, "--super-prefix=%s%s/",
1569                                    get_super_prefix_or_empty(), path);
1570         argv_array_pushl(&cp.args, "read-tree", "-u", "--reset", NULL);
1571
1572         argv_array_push(&cp.args, EMPTY_TREE_SHA1_HEX);
1573
1574         if (run_command(&cp))
1575                 die("could not reset submodule index");
1576 }
1577
1578 /**
1579  * Moves a submodule at a given path from a given head to another new head.
1580  * For edge cases (a submodule coming into existence or removing a submodule)
1581  * pass NULL for old or new respectively.
1582  */
1583 int submodule_move_head(const char *path,
1584                          const char *old_head,
1585                          const char *new_head,
1586                          unsigned flags)
1587 {
1588         int ret = 0;
1589         struct child_process cp = CHILD_PROCESS_INIT;
1590         const struct submodule *sub;
1591         int *error_code_ptr, error_code;
1592
1593         if (!is_submodule_active(the_repository, path))
1594                 return 0;
1595
1596         if (flags & SUBMODULE_MOVE_HEAD_FORCE)
1597                 /*
1598                  * Pass non NULL pointer to is_submodule_populated_gently
1599                  * to prevent die()-ing. We'll use connect_work_tree_and_git_dir
1600                  * to fixup the submodule in the force case later.
1601                  */
1602                 error_code_ptr = &error_code;
1603         else
1604                 error_code_ptr = NULL;
1605
1606         if (old_head && !is_submodule_populated_gently(path, error_code_ptr))
1607                 return 0;
1608
1609         sub = submodule_from_path(the_repository, &null_oid, path);
1610
1611         if (!sub)
1612                 die("BUG: could not get submodule information for '%s'", path);
1613
1614         if (old_head && !(flags & SUBMODULE_MOVE_HEAD_FORCE)) {
1615                 /* Check if the submodule has a dirty index. */
1616                 if (submodule_has_dirty_index(sub))
1617                         return error(_("submodule '%s' has dirty index"), path);
1618         }
1619
1620         if (!(flags & SUBMODULE_MOVE_HEAD_DRY_RUN)) {
1621                 if (old_head) {
1622                         if (!submodule_uses_gitfile(path))
1623                                 absorb_git_dir_into_superproject("", path,
1624                                         ABSORB_GITDIR_RECURSE_SUBMODULES);
1625                 } else {
1626                         char *gitdir = xstrfmt("%s/modules/%s",
1627                                     get_git_common_dir(), sub->name);
1628                         connect_work_tree_and_git_dir(path, gitdir, 0);
1629                         free(gitdir);
1630
1631                         /* make sure the index is clean as well */
1632                         submodule_reset_index(path);
1633                 }
1634
1635                 if (old_head && (flags & SUBMODULE_MOVE_HEAD_FORCE)) {
1636                         char *gitdir = xstrfmt("%s/modules/%s",
1637                                     get_git_common_dir(), sub->name);
1638                         connect_work_tree_and_git_dir(path, gitdir, 1);
1639                         free(gitdir);
1640                 }
1641         }
1642
1643         prepare_submodule_repo_env(&cp.env_array);
1644
1645         cp.git_cmd = 1;
1646         cp.no_stdin = 1;
1647         cp.dir = path;
1648
1649         argv_array_pushf(&cp.args, "--super-prefix=%s%s/",
1650                         get_super_prefix_or_empty(), path);
1651         argv_array_pushl(&cp.args, "read-tree", "--recurse-submodules", NULL);
1652
1653         if (flags & SUBMODULE_MOVE_HEAD_DRY_RUN)
1654                 argv_array_push(&cp.args, "-n");
1655         else
1656                 argv_array_push(&cp.args, "-u");
1657
1658         if (flags & SUBMODULE_MOVE_HEAD_FORCE)
1659                 argv_array_push(&cp.args, "--reset");
1660         else
1661                 argv_array_push(&cp.args, "-m");
1662
1663         if (!(flags & SUBMODULE_MOVE_HEAD_FORCE))
1664                 argv_array_push(&cp.args, old_head ? old_head : EMPTY_TREE_SHA1_HEX);
1665
1666         argv_array_push(&cp.args, new_head ? new_head : EMPTY_TREE_SHA1_HEX);
1667
1668         if (run_command(&cp)) {
1669                 ret = -1;
1670                 goto out;
1671         }
1672
1673         if (!(flags & SUBMODULE_MOVE_HEAD_DRY_RUN)) {
1674                 if (new_head) {
1675                         child_process_init(&cp);
1676                         /* also set the HEAD accordingly */
1677                         cp.git_cmd = 1;
1678                         cp.no_stdin = 1;
1679                         cp.dir = path;
1680
1681                         prepare_submodule_repo_env(&cp.env_array);
1682                         argv_array_pushl(&cp.args, "update-ref", "HEAD",
1683                                          "--no-deref", new_head, NULL);
1684
1685                         if (run_command(&cp)) {
1686                                 ret = -1;
1687                                 goto out;
1688                         }
1689                 } else {
1690                         struct strbuf sb = STRBUF_INIT;
1691
1692                         strbuf_addf(&sb, "%s/.git", path);
1693                         unlink_or_warn(sb.buf);
1694                         strbuf_release(&sb);
1695
1696                         if (is_empty_dir(path))
1697                                 rmdir_or_warn(path);
1698                 }
1699         }
1700 out:
1701         return ret;
1702 }
1703
1704 static int find_first_merges(struct object_array *result, const char *path,
1705                 struct commit *a, struct commit *b)
1706 {
1707         int i, j;
1708         struct object_array merges = OBJECT_ARRAY_INIT;
1709         struct commit *commit;
1710         int contains_another;
1711
1712         char merged_revision[42];
1713         const char *rev_args[] = { "rev-list", "--merges", "--ancestry-path",
1714                                    "--all", merged_revision, NULL };
1715         struct rev_info revs;
1716         struct setup_revision_opt rev_opts;
1717
1718         memset(result, 0, sizeof(struct object_array));
1719         memset(&rev_opts, 0, sizeof(rev_opts));
1720
1721         /* get all revisions that merge commit a */
1722         xsnprintf(merged_revision, sizeof(merged_revision), "^%s",
1723                         oid_to_hex(&a->object.oid));
1724         init_revisions(&revs, NULL);
1725         rev_opts.submodule = path;
1726         /* FIXME: can't handle linked worktrees in submodules yet */
1727         revs.single_worktree = path != NULL;
1728         setup_revisions(ARRAY_SIZE(rev_args)-1, rev_args, &revs, &rev_opts);
1729
1730         /* save all revisions from the above list that contain b */
1731         if (prepare_revision_walk(&revs))
1732                 die("revision walk setup failed");
1733         while ((commit = get_revision(&revs)) != NULL) {
1734                 struct object *o = &(commit->object);
1735                 if (in_merge_bases(b, commit))
1736                         add_object_array(o, NULL, &merges);
1737         }
1738         reset_revision_walk();
1739
1740         /* Now we've got all merges that contain a and b. Prune all
1741          * merges that contain another found merge and save them in
1742          * result.
1743          */
1744         for (i = 0; i < merges.nr; i++) {
1745                 struct commit *m1 = (struct commit *) merges.objects[i].item;
1746
1747                 contains_another = 0;
1748                 for (j = 0; j < merges.nr; j++) {
1749                         struct commit *m2 = (struct commit *) merges.objects[j].item;
1750                         if (i != j && in_merge_bases(m2, m1)) {
1751                                 contains_another = 1;
1752                                 break;
1753                         }
1754                 }
1755
1756                 if (!contains_another)
1757                         add_object_array(merges.objects[i].item, NULL, result);
1758         }
1759
1760         object_array_clear(&merges);
1761         return result->nr;
1762 }
1763
1764 static void print_commit(struct commit *commit)
1765 {
1766         struct strbuf sb = STRBUF_INIT;
1767         struct pretty_print_context ctx = {0};
1768         ctx.date_mode.type = DATE_NORMAL;
1769         format_commit_message(commit, " %h: %m %s", &sb, &ctx);
1770         fprintf(stderr, "%s\n", sb.buf);
1771         strbuf_release(&sb);
1772 }
1773
1774 #define MERGE_WARNING(path, msg) \
1775         warning("Failed to merge submodule %s (%s)", path, msg);
1776
1777 int merge_submodule(struct object_id *result, const char *path,
1778                     const struct object_id *base, const struct object_id *a,
1779                     const struct object_id *b, int search)
1780 {
1781         struct commit *commit_base, *commit_a, *commit_b;
1782         int parent_count;
1783         struct object_array merges;
1784
1785         int i;
1786
1787         /* store a in result in case we fail */
1788         oidcpy(result, a);
1789
1790         /* we can not handle deletion conflicts */
1791         if (is_null_oid(base))
1792                 return 0;
1793         if (is_null_oid(a))
1794                 return 0;
1795         if (is_null_oid(b))
1796                 return 0;
1797
1798         if (add_submodule_odb(path)) {
1799                 MERGE_WARNING(path, "not checked out");
1800                 return 0;
1801         }
1802
1803         if (!(commit_base = lookup_commit_reference(base)) ||
1804             !(commit_a = lookup_commit_reference(a)) ||
1805             !(commit_b = lookup_commit_reference(b))) {
1806                 MERGE_WARNING(path, "commits not present");
1807                 return 0;
1808         }
1809
1810         /* check whether both changes are forward */
1811         if (!in_merge_bases(commit_base, commit_a) ||
1812             !in_merge_bases(commit_base, commit_b)) {
1813                 MERGE_WARNING(path, "commits don't follow merge-base");
1814                 return 0;
1815         }
1816
1817         /* Case #1: a is contained in b or vice versa */
1818         if (in_merge_bases(commit_a, commit_b)) {
1819                 oidcpy(result, b);
1820                 return 1;
1821         }
1822         if (in_merge_bases(commit_b, commit_a)) {
1823                 oidcpy(result, a);
1824                 return 1;
1825         }
1826
1827         /*
1828          * Case #2: There are one or more merges that contain a and b in
1829          * the submodule. If there is only one, then present it as a
1830          * suggestion to the user, but leave it marked unmerged so the
1831          * user needs to confirm the resolution.
1832          */
1833
1834         /* Skip the search if makes no sense to the calling context.  */
1835         if (!search)
1836                 return 0;
1837
1838         /* find commit which merges them */
1839         parent_count = find_first_merges(&merges, path, commit_a, commit_b);
1840         switch (parent_count) {
1841         case 0:
1842                 MERGE_WARNING(path, "merge following commits not found");
1843                 break;
1844
1845         case 1:
1846                 MERGE_WARNING(path, "not fast-forward");
1847                 fprintf(stderr, "Found a possible merge resolution "
1848                                 "for the submodule:\n");
1849                 print_commit((struct commit *) merges.objects[0].item);
1850                 fprintf(stderr,
1851                         "If this is correct simply add it to the index "
1852                         "for example\n"
1853                         "by using:\n\n"
1854                         "  git update-index --cacheinfo 160000 %s \"%s\"\n\n"
1855                         "which will accept this suggestion.\n",
1856                         oid_to_hex(&merges.objects[0].item->oid), path);
1857                 break;
1858
1859         default:
1860                 MERGE_WARNING(path, "multiple merges found");
1861                 for (i = 0; i < merges.nr; i++)
1862                         print_commit((struct commit *) merges.objects[i].item);
1863         }
1864
1865         object_array_clear(&merges);
1866         return 0;
1867 }
1868
1869 /*
1870  * Embeds a single submodules git directory into the superprojects git dir,
1871  * non recursively.
1872  */
1873 static void relocate_single_git_dir_into_superproject(const char *prefix,
1874                                                       const char *path)
1875 {
1876         char *old_git_dir = NULL, *real_old_git_dir = NULL, *real_new_git_dir = NULL;
1877         const char *new_git_dir;
1878         const struct submodule *sub;
1879
1880         if (submodule_uses_worktrees(path))
1881                 die(_("relocate_gitdir for submodule '%s' with "
1882                       "more than one worktree not supported"), path);
1883
1884         old_git_dir = xstrfmt("%s/.git", path);
1885         if (read_gitfile(old_git_dir))
1886                 /* If it is an actual gitfile, it doesn't need migration. */
1887                 return;
1888
1889         real_old_git_dir = real_pathdup(old_git_dir, 1);
1890
1891         sub = submodule_from_path(the_repository, &null_oid, path);
1892         if (!sub)
1893                 die(_("could not lookup name for submodule '%s'"), path);
1894
1895         new_git_dir = git_path("modules/%s", sub->name);
1896         if (safe_create_leading_directories_const(new_git_dir) < 0)
1897                 die(_("could not create directory '%s'"), new_git_dir);
1898         real_new_git_dir = real_pathdup(new_git_dir, 1);
1899
1900         fprintf(stderr, _("Migrating git directory of '%s%s' from\n'%s' to\n'%s'\n"),
1901                 get_super_prefix_or_empty(), path,
1902                 real_old_git_dir, real_new_git_dir);
1903
1904         relocate_gitdir(path, real_old_git_dir, real_new_git_dir);
1905
1906         free(old_git_dir);
1907         free(real_old_git_dir);
1908         free(real_new_git_dir);
1909 }
1910
1911 /*
1912  * Migrate the git directory of the submodule given by path from
1913  * having its git directory within the working tree to the git dir nested
1914  * in its superprojects git dir under modules/.
1915  */
1916 void absorb_git_dir_into_superproject(const char *prefix,
1917                                       const char *path,
1918                                       unsigned flags)
1919 {
1920         int err_code;
1921         const char *sub_git_dir;
1922         struct strbuf gitdir = STRBUF_INIT;
1923         strbuf_addf(&gitdir, "%s/.git", path);
1924         sub_git_dir = resolve_gitdir_gently(gitdir.buf, &err_code);
1925
1926         /* Not populated? */
1927         if (!sub_git_dir) {
1928                 const struct submodule *sub;
1929
1930                 if (err_code == READ_GITFILE_ERR_STAT_FAILED) {
1931                         /* unpopulated as expected */
1932                         strbuf_release(&gitdir);
1933                         return;
1934                 }
1935
1936                 if (err_code != READ_GITFILE_ERR_NOT_A_REPO)
1937                         /* We don't know what broke here. */
1938                         read_gitfile_error_die(err_code, path, NULL);
1939
1940                 /*
1941                 * Maybe populated, but no git directory was found?
1942                 * This can happen if the superproject is a submodule
1943                 * itself and was just absorbed. The absorption of the
1944                 * superproject did not rewrite the git file links yet,
1945                 * fix it now.
1946                 */
1947                 sub = submodule_from_path(the_repository, &null_oid, path);
1948                 if (!sub)
1949                         die(_("could not lookup name for submodule '%s'"), path);
1950                 connect_work_tree_and_git_dir(path,
1951                         git_path("modules/%s", sub->name), 0);
1952         } else {
1953                 /* Is it already absorbed into the superprojects git dir? */
1954                 char *real_sub_git_dir = real_pathdup(sub_git_dir, 1);
1955                 char *real_common_git_dir = real_pathdup(get_git_common_dir(), 1);
1956
1957                 if (!starts_with(real_sub_git_dir, real_common_git_dir))
1958                         relocate_single_git_dir_into_superproject(prefix, path);
1959
1960                 free(real_sub_git_dir);
1961                 free(real_common_git_dir);
1962         }
1963         strbuf_release(&gitdir);
1964
1965         if (flags & ABSORB_GITDIR_RECURSE_SUBMODULES) {
1966                 struct child_process cp = CHILD_PROCESS_INIT;
1967                 struct strbuf sb = STRBUF_INIT;
1968
1969                 if (flags & ~ABSORB_GITDIR_RECURSE_SUBMODULES)
1970                         die("BUG: we don't know how to pass the flags down?");
1971
1972                 strbuf_addstr(&sb, get_super_prefix_or_empty());
1973                 strbuf_addstr(&sb, path);
1974                 strbuf_addch(&sb, '/');
1975
1976                 cp.dir = path;
1977                 cp.git_cmd = 1;
1978                 cp.no_stdin = 1;
1979                 argv_array_pushl(&cp.args, "--super-prefix", sb.buf,
1980                                            "submodule--helper",
1981                                            "absorb-git-dirs", NULL);
1982                 prepare_submodule_repo_env(&cp.env_array);
1983                 if (run_command(&cp))
1984                         die(_("could not recurse into submodule '%s'"), path);
1985
1986                 strbuf_release(&sb);
1987         }
1988 }
1989
1990 const char *get_superproject_working_tree(void)
1991 {
1992         struct child_process cp = CHILD_PROCESS_INIT;
1993         struct strbuf sb = STRBUF_INIT;
1994         const char *one_up = real_path_if_valid("../");
1995         const char *cwd = xgetcwd();
1996         const char *ret = NULL;
1997         const char *subpath;
1998         int code;
1999         ssize_t len;
2000
2001         if (!is_inside_work_tree())
2002                 /*
2003                  * FIXME:
2004                  * We might have a superproject, but it is harder
2005                  * to determine.
2006                  */
2007                 return NULL;
2008
2009         if (!one_up)
2010                 return NULL;
2011
2012         subpath = relative_path(cwd, one_up, &sb);
2013
2014         prepare_submodule_repo_env(&cp.env_array);
2015         argv_array_pop(&cp.env_array);
2016
2017         argv_array_pushl(&cp.args, "--literal-pathspecs", "-C", "..",
2018                         "ls-files", "-z", "--stage", "--full-name", "--",
2019                         subpath, NULL);
2020         strbuf_reset(&sb);
2021
2022         cp.no_stdin = 1;
2023         cp.no_stderr = 1;
2024         cp.out = -1;
2025         cp.git_cmd = 1;
2026
2027         if (start_command(&cp))
2028                 die(_("could not start ls-files in .."));
2029
2030         len = strbuf_read(&sb, cp.out, PATH_MAX);
2031         close(cp.out);
2032
2033         if (starts_with(sb.buf, "160000")) {
2034                 int super_sub_len;
2035                 int cwd_len = strlen(cwd);
2036                 char *super_sub, *super_wt;
2037
2038                 /*
2039                  * There is a superproject having this repo as a submodule.
2040                  * The format is <mode> SP <hash> SP <stage> TAB <full name> \0,
2041                  * We're only interested in the name after the tab.
2042                  */
2043                 super_sub = strchr(sb.buf, '\t') + 1;
2044                 super_sub_len = sb.buf + sb.len - super_sub - 1;
2045
2046                 if (super_sub_len > cwd_len ||
2047                     strcmp(&cwd[cwd_len - super_sub_len], super_sub))
2048                         die (_("BUG: returned path string doesn't match cwd?"));
2049
2050                 super_wt = xstrdup(cwd);
2051                 super_wt[cwd_len - super_sub_len] = '\0';
2052
2053                 ret = real_path(super_wt);
2054                 free(super_wt);
2055         }
2056         strbuf_release(&sb);
2057
2058         code = finish_command(&cp);
2059
2060         if (code == 128)
2061                 /* '../' is not a git repository */
2062                 return NULL;
2063         if (code == 0 && len == 0)
2064                 /* There is an unrelated git repository at '../' */
2065                 return NULL;
2066         if (code)
2067                 die(_("ls-tree returned unexpected return code %d"), code);
2068
2069         return ret;
2070 }
2071
2072 /*
2073  * Put the gitdir for a submodule (given relative to the main
2074  * repository worktree) into `buf`, or return -1 on error.
2075  */
2076 int submodule_to_gitdir(struct strbuf *buf, const char *submodule)
2077 {
2078         const struct submodule *sub;
2079         const char *git_dir;
2080         int ret = 0;
2081
2082         strbuf_reset(buf);
2083         strbuf_addstr(buf, submodule);
2084         strbuf_complete(buf, '/');
2085         strbuf_addstr(buf, ".git");
2086
2087         git_dir = read_gitfile(buf->buf);
2088         if (git_dir) {
2089                 strbuf_reset(buf);
2090                 strbuf_addstr(buf, git_dir);
2091         }
2092         if (!is_git_directory(buf->buf)) {
2093                 sub = submodule_from_path(the_repository, &null_oid, submodule);
2094                 if (!sub) {
2095                         ret = -1;
2096                         goto cleanup;
2097                 }
2098                 strbuf_reset(buf);
2099                 strbuf_git_path(buf, "%s/%s", "modules", sub->name);
2100         }
2101
2102 cleanup:
2103         return ret;
2104 }