Merge branch 'rh/diff-orderfile-doc'
[git] / submodule.c
1 #include "cache.h"
2 #include "submodule-config.h"
3 #include "submodule.h"
4 #include "dir.h"
5 #include "diff.h"
6 #include "commit.h"
7 #include "revision.h"
8 #include "run-command.h"
9 #include "diffcore.h"
10 #include "refs.h"
11 #include "string-list.h"
12 #include "sha1-array.h"
13 #include "argv-array.h"
14 #include "blob.h"
15 #include "thread-utils.h"
16 #include "quote.h"
17 #include "worktree.h"
18
19 static int config_fetch_recurse_submodules = RECURSE_SUBMODULES_ON_DEMAND;
20 static int parallel_jobs = 1;
21 static struct string_list changed_submodule_paths = STRING_LIST_INIT_NODUP;
22 static int initialized_fetch_ref_tips;
23 static struct sha1_array ref_tips_before_fetch;
24 static struct sha1_array ref_tips_after_fetch;
25
26 /*
27  * The following flag is set if the .gitmodules file is unmerged. We then
28  * disable recursion for all submodules where .git/config doesn't have a
29  * matching config entry because we can't guess what might be configured in
30  * .gitmodules unless the user resolves the conflict. When a command line
31  * option is given (which always overrides configuration) this flag will be
32  * ignored.
33  */
34 static int gitmodules_is_unmerged;
35
36 /*
37  * This flag is set if the .gitmodules file had unstaged modifications on
38  * startup. This must be checked before allowing modifications to the
39  * .gitmodules file with the intention to stage them later, because when
40  * continuing we would stage the modifications the user didn't stage herself
41  * too. That might change in a future version when we learn to stage the
42  * changes we do ourselves without staging any previous modifications.
43  */
44 static int gitmodules_is_modified;
45
46 int is_staging_gitmodules_ok(void)
47 {
48         return !gitmodules_is_modified;
49 }
50
51 /*
52  * Try to update the "path" entry in the "submodule.<name>" section of the
53  * .gitmodules file. Return 0 only if a .gitmodules file was found, a section
54  * with the correct path=<oldpath> setting was found and we could update it.
55  */
56 int update_path_in_gitmodules(const char *oldpath, const char *newpath)
57 {
58         struct strbuf entry = STRBUF_INIT;
59         const struct submodule *submodule;
60
61         if (!file_exists(".gitmodules")) /* Do nothing without .gitmodules */
62                 return -1;
63
64         if (gitmodules_is_unmerged)
65                 die(_("Cannot change unmerged .gitmodules, resolve merge conflicts first"));
66
67         submodule = submodule_from_path(null_sha1, oldpath);
68         if (!submodule || !submodule->name) {
69                 warning(_("Could not find section in .gitmodules where path=%s"), oldpath);
70                 return -1;
71         }
72         strbuf_addstr(&entry, "submodule.");
73         strbuf_addstr(&entry, submodule->name);
74         strbuf_addstr(&entry, ".path");
75         if (git_config_set_in_file_gently(".gitmodules", entry.buf, newpath) < 0) {
76                 /* Maybe the user already did that, don't error out here */
77                 warning(_("Could not update .gitmodules entry %s"), entry.buf);
78                 strbuf_release(&entry);
79                 return -1;
80         }
81         strbuf_release(&entry);
82         return 0;
83 }
84
85 /*
86  * Try to remove the "submodule.<name>" section from .gitmodules where the given
87  * path is configured. Return 0 only if a .gitmodules file was found, a section
88  * with the correct path=<path> setting was found and we could remove it.
89  */
90 int remove_path_from_gitmodules(const char *path)
91 {
92         struct strbuf sect = STRBUF_INIT;
93         const struct submodule *submodule;
94
95         if (!file_exists(".gitmodules")) /* Do nothing without .gitmodules */
96                 return -1;
97
98         if (gitmodules_is_unmerged)
99                 die(_("Cannot change unmerged .gitmodules, resolve merge conflicts first"));
100
101         submodule = submodule_from_path(null_sha1, path);
102         if (!submodule || !submodule->name) {
103                 warning(_("Could not find section in .gitmodules where path=%s"), path);
104                 return -1;
105         }
106         strbuf_addstr(&sect, "submodule.");
107         strbuf_addstr(&sect, submodule->name);
108         if (git_config_rename_section_in_file(".gitmodules", sect.buf, NULL) < 0) {
109                 /* Maybe the user already did that, don't error out here */
110                 warning(_("Could not remove .gitmodules entry for %s"), path);
111                 strbuf_release(&sect);
112                 return -1;
113         }
114         strbuf_release(&sect);
115         return 0;
116 }
117
118 void stage_updated_gitmodules(void)
119 {
120         if (add_file_to_cache(".gitmodules", 0))
121                 die(_("staging updated .gitmodules failed"));
122 }
123
124 static int add_submodule_odb(const char *path)
125 {
126         struct strbuf objects_directory = STRBUF_INIT;
127         int ret = 0;
128
129         ret = strbuf_git_path_submodule(&objects_directory, path, "objects/");
130         if (ret)
131                 goto done;
132         if (!is_directory(objects_directory.buf)) {
133                 ret = -1;
134                 goto done;
135         }
136         add_to_alternates_memory(objects_directory.buf);
137 done:
138         strbuf_release(&objects_directory);
139         return ret;
140 }
141
142 void set_diffopt_flags_from_submodule_config(struct diff_options *diffopt,
143                                              const char *path)
144 {
145         const struct submodule *submodule = submodule_from_path(null_sha1, path);
146         if (submodule) {
147                 if (submodule->ignore)
148                         handle_ignore_submodules_arg(diffopt, submodule->ignore);
149                 else if (gitmodules_is_unmerged)
150                         DIFF_OPT_SET(diffopt, IGNORE_SUBMODULES);
151         }
152 }
153
154 int submodule_config(const char *var, const char *value, void *cb)
155 {
156         if (!strcmp(var, "submodule.fetchjobs")) {
157                 parallel_jobs = git_config_int(var, value);
158                 if (parallel_jobs < 0)
159                         die(_("negative values not allowed for submodule.fetchJobs"));
160                 return 0;
161         } else if (starts_with(var, "submodule."))
162                 return parse_submodule_config_option(var, value);
163         else if (!strcmp(var, "fetch.recursesubmodules")) {
164                 config_fetch_recurse_submodules = parse_fetch_recurse_submodules_arg(var, value);
165                 return 0;
166         }
167         return 0;
168 }
169
170 void gitmodules_config(void)
171 {
172         const char *work_tree = get_git_work_tree();
173         if (work_tree) {
174                 struct strbuf gitmodules_path = STRBUF_INIT;
175                 int pos;
176                 strbuf_addstr(&gitmodules_path, work_tree);
177                 strbuf_addstr(&gitmodules_path, "/.gitmodules");
178                 if (read_cache() < 0)
179                         die("index file corrupt");
180                 pos = cache_name_pos(".gitmodules", 11);
181                 if (pos < 0) { /* .gitmodules not found or isn't merged */
182                         pos = -1 - pos;
183                         if (active_nr > pos) {  /* there is a .gitmodules */
184                                 const struct cache_entry *ce = active_cache[pos];
185                                 if (ce_namelen(ce) == 11 &&
186                                     !memcmp(ce->name, ".gitmodules", 11))
187                                         gitmodules_is_unmerged = 1;
188                         }
189                 } else if (pos < active_nr) {
190                         struct stat st;
191                         if (lstat(".gitmodules", &st) == 0 &&
192                             ce_match_stat(active_cache[pos], &st, 0) & DATA_CHANGED)
193                                 gitmodules_is_modified = 1;
194                 }
195
196                 if (!gitmodules_is_unmerged)
197                         git_config_from_file(submodule_config, gitmodules_path.buf, NULL);
198                 strbuf_release(&gitmodules_path);
199         }
200 }
201
202 void gitmodules_config_sha1(const unsigned char *commit_sha1)
203 {
204         struct strbuf rev = STRBUF_INIT;
205         unsigned char sha1[20];
206
207         if (gitmodule_sha1_from_commit(commit_sha1, sha1, &rev)) {
208                 git_config_from_blob_sha1(submodule_config, rev.buf,
209                                           sha1, NULL);
210         }
211         strbuf_release(&rev);
212 }
213
214 /*
215  * Determine if a submodule has been initialized at a given 'path'
216  */
217 int is_submodule_initialized(const char *path)
218 {
219         int ret = 0;
220         const struct submodule *module = NULL;
221
222         module = submodule_from_path(null_sha1, path);
223
224         if (module) {
225                 char *key = xstrfmt("submodule.%s.url", module->name);
226                 char *value = NULL;
227
228                 ret = !git_config_get_string(key, &value);
229
230                 free(value);
231                 free(key);
232         }
233
234         return ret;
235 }
236
237 /*
238  * Determine if a submodule has been populated at a given 'path'
239  */
240 int is_submodule_populated(const char *path)
241 {
242         int ret = 0;
243         char *gitdir = xstrfmt("%s/.git", path);
244
245         if (resolve_gitdir(gitdir))
246                 ret = 1;
247
248         free(gitdir);
249         return ret;
250 }
251
252 int parse_submodule_update_strategy(const char *value,
253                 struct submodule_update_strategy *dst)
254 {
255         free((void*)dst->command);
256         dst->command = NULL;
257         if (!strcmp(value, "none"))
258                 dst->type = SM_UPDATE_NONE;
259         else if (!strcmp(value, "checkout"))
260                 dst->type = SM_UPDATE_CHECKOUT;
261         else if (!strcmp(value, "rebase"))
262                 dst->type = SM_UPDATE_REBASE;
263         else if (!strcmp(value, "merge"))
264                 dst->type = SM_UPDATE_MERGE;
265         else if (skip_prefix(value, "!", &value)) {
266                 dst->type = SM_UPDATE_COMMAND;
267                 dst->command = xstrdup(value);
268         } else
269                 return -1;
270         return 0;
271 }
272
273 const char *submodule_strategy_to_string(const struct submodule_update_strategy *s)
274 {
275         struct strbuf sb = STRBUF_INIT;
276         switch (s->type) {
277         case SM_UPDATE_CHECKOUT:
278                 return "checkout";
279         case SM_UPDATE_MERGE:
280                 return "merge";
281         case SM_UPDATE_REBASE:
282                 return "rebase";
283         case SM_UPDATE_NONE:
284                 return "none";
285         case SM_UPDATE_UNSPECIFIED:
286                 return NULL;
287         case SM_UPDATE_COMMAND:
288                 strbuf_addf(&sb, "!%s", s->command);
289                 return strbuf_detach(&sb, NULL);
290         }
291         return NULL;
292 }
293
294 void handle_ignore_submodules_arg(struct diff_options *diffopt,
295                                   const char *arg)
296 {
297         DIFF_OPT_CLR(diffopt, IGNORE_SUBMODULES);
298         DIFF_OPT_CLR(diffopt, IGNORE_UNTRACKED_IN_SUBMODULES);
299         DIFF_OPT_CLR(diffopt, IGNORE_DIRTY_SUBMODULES);
300
301         if (!strcmp(arg, "all"))
302                 DIFF_OPT_SET(diffopt, IGNORE_SUBMODULES);
303         else if (!strcmp(arg, "untracked"))
304                 DIFF_OPT_SET(diffopt, IGNORE_UNTRACKED_IN_SUBMODULES);
305         else if (!strcmp(arg, "dirty"))
306                 DIFF_OPT_SET(diffopt, IGNORE_DIRTY_SUBMODULES);
307         else if (strcmp(arg, "none"))
308                 die("bad --ignore-submodules argument: %s", arg);
309 }
310
311 static int prepare_submodule_summary(struct rev_info *rev, const char *path,
312                 struct commit *left, struct commit *right,
313                 struct commit_list *merge_bases)
314 {
315         struct commit_list *list;
316
317         init_revisions(rev, NULL);
318         setup_revisions(0, NULL, rev, NULL);
319         rev->left_right = 1;
320         rev->first_parent_only = 1;
321         left->object.flags |= SYMMETRIC_LEFT;
322         add_pending_object(rev, &left->object, path);
323         add_pending_object(rev, &right->object, path);
324         for (list = merge_bases; list; list = list->next) {
325                 list->item->object.flags |= UNINTERESTING;
326                 add_pending_object(rev, &list->item->object,
327                         oid_to_hex(&list->item->object.oid));
328         }
329         return prepare_revision_walk(rev);
330 }
331
332 static void print_submodule_summary(struct rev_info *rev, FILE *f,
333                 const char *line_prefix,
334                 const char *del, const char *add, const char *reset)
335 {
336         static const char format[] = "  %m %s";
337         struct strbuf sb = STRBUF_INIT;
338         struct commit *commit;
339
340         while ((commit = get_revision(rev))) {
341                 struct pretty_print_context ctx = {0};
342                 ctx.date_mode = rev->date_mode;
343                 ctx.output_encoding = get_log_output_encoding();
344                 strbuf_setlen(&sb, 0);
345                 strbuf_addstr(&sb, line_prefix);
346                 if (commit->object.flags & SYMMETRIC_LEFT) {
347                         if (del)
348                                 strbuf_addstr(&sb, del);
349                 }
350                 else if (add)
351                         strbuf_addstr(&sb, add);
352                 format_commit_message(commit, format, &sb, &ctx);
353                 if (reset)
354                         strbuf_addstr(&sb, reset);
355                 strbuf_addch(&sb, '\n');
356                 fprintf(f, "%s", sb.buf);
357         }
358         strbuf_release(&sb);
359 }
360
361 /* Helper function to display the submodule header line prior to the full
362  * summary output. If it can locate the submodule objects directory it will
363  * attempt to lookup both the left and right commits and put them into the
364  * left and right pointers.
365  */
366 static void show_submodule_header(FILE *f, const char *path,
367                 const char *line_prefix,
368                 struct object_id *one, struct object_id *two,
369                 unsigned dirty_submodule, const char *meta,
370                 const char *reset,
371                 struct commit **left, struct commit **right,
372                 struct commit_list **merge_bases)
373 {
374         const char *message = NULL;
375         struct strbuf sb = STRBUF_INIT;
376         int fast_forward = 0, fast_backward = 0;
377
378         if (dirty_submodule & DIRTY_SUBMODULE_UNTRACKED)
379                 fprintf(f, "%sSubmodule %s contains untracked content\n",
380                         line_prefix, path);
381         if (dirty_submodule & DIRTY_SUBMODULE_MODIFIED)
382                 fprintf(f, "%sSubmodule %s contains modified content\n",
383                         line_prefix, path);
384
385         if (is_null_oid(one))
386                 message = "(new submodule)";
387         else if (is_null_oid(two))
388                 message = "(submodule deleted)";
389
390         if (add_submodule_odb(path)) {
391                 if (!message)
392                         message = "(not initialized)";
393                 goto output_header;
394         }
395
396         /*
397          * Attempt to lookup the commit references, and determine if this is
398          * a fast forward or fast backwards update.
399          */
400         *left = lookup_commit_reference(one->hash);
401         *right = lookup_commit_reference(two->hash);
402
403         /*
404          * Warn about missing commits in the submodule project, but only if
405          * they aren't null.
406          */
407         if ((!is_null_oid(one) && !*left) ||
408              (!is_null_oid(two) && !*right))
409                 message = "(commits not present)";
410
411         *merge_bases = get_merge_bases(*left, *right);
412         if (*merge_bases) {
413                 if ((*merge_bases)->item == *left)
414                         fast_forward = 1;
415                 else if ((*merge_bases)->item == *right)
416                         fast_backward = 1;
417         }
418
419         if (!oidcmp(one, two)) {
420                 strbuf_release(&sb);
421                 return;
422         }
423
424 output_header:
425         strbuf_addf(&sb, "%s%sSubmodule %s ", line_prefix, meta, path);
426         strbuf_add_unique_abbrev(&sb, one->hash, DEFAULT_ABBREV);
427         strbuf_addstr(&sb, (fast_backward || fast_forward) ? ".." : "...");
428         strbuf_add_unique_abbrev(&sb, two->hash, DEFAULT_ABBREV);
429         if (message)
430                 strbuf_addf(&sb, " %s%s\n", message, reset);
431         else
432                 strbuf_addf(&sb, "%s:%s\n", fast_backward ? " (rewind)" : "", reset);
433         fwrite(sb.buf, sb.len, 1, f);
434
435         strbuf_release(&sb);
436 }
437
438 void show_submodule_summary(FILE *f, const char *path,
439                 const char *line_prefix,
440                 struct object_id *one, struct object_id *two,
441                 unsigned dirty_submodule, const char *meta,
442                 const char *del, const char *add, const char *reset)
443 {
444         struct rev_info rev;
445         struct commit *left = NULL, *right = NULL;
446         struct commit_list *merge_bases = NULL;
447
448         show_submodule_header(f, path, line_prefix, one, two, dirty_submodule,
449                               meta, reset, &left, &right, &merge_bases);
450
451         /*
452          * If we don't have both a left and a right pointer, there is no
453          * reason to try and display a summary. The header line should contain
454          * all the information the user needs.
455          */
456         if (!left || !right)
457                 goto out;
458
459         /* Treat revision walker failure the same as missing commits */
460         if (prepare_submodule_summary(&rev, path, left, right, merge_bases)) {
461                 fprintf(f, "%s(revision walker failed)\n", line_prefix);
462                 goto out;
463         }
464
465         print_submodule_summary(&rev, f, line_prefix, del, add, reset);
466
467 out:
468         if (merge_bases)
469                 free_commit_list(merge_bases);
470         clear_commit_marks(left, ~0);
471         clear_commit_marks(right, ~0);
472 }
473
474 void show_submodule_inline_diff(FILE *f, const char *path,
475                 const char *line_prefix,
476                 struct object_id *one, struct object_id *two,
477                 unsigned dirty_submodule, const char *meta,
478                 const char *del, const char *add, const char *reset,
479                 const struct diff_options *o)
480 {
481         const struct object_id *old = &empty_tree_oid, *new = &empty_tree_oid;
482         struct commit *left = NULL, *right = NULL;
483         struct commit_list *merge_bases = NULL;
484         struct strbuf submodule_dir = STRBUF_INIT;
485         struct child_process cp = CHILD_PROCESS_INIT;
486
487         show_submodule_header(f, path, line_prefix, one, two, dirty_submodule,
488                               meta, reset, &left, &right, &merge_bases);
489
490         /* We need a valid left and right commit to display a difference */
491         if (!(left || is_null_oid(one)) ||
492             !(right || is_null_oid(two)))
493                 goto done;
494
495         if (left)
496                 old = one;
497         if (right)
498                 new = two;
499
500         fflush(f);
501         cp.git_cmd = 1;
502         cp.dir = path;
503         cp.out = dup(fileno(f));
504         cp.no_stdin = 1;
505
506         /* TODO: other options may need to be passed here. */
507         argv_array_push(&cp.args, "diff");
508         argv_array_pushf(&cp.args, "--line-prefix=%s", line_prefix);
509         if (DIFF_OPT_TST(o, REVERSE_DIFF)) {
510                 argv_array_pushf(&cp.args, "--src-prefix=%s%s/",
511                                  o->b_prefix, path);
512                 argv_array_pushf(&cp.args, "--dst-prefix=%s%s/",
513                                  o->a_prefix, path);
514         } else {
515                 argv_array_pushf(&cp.args, "--src-prefix=%s%s/",
516                                  o->a_prefix, path);
517                 argv_array_pushf(&cp.args, "--dst-prefix=%s%s/",
518                                  o->b_prefix, path);
519         }
520         argv_array_push(&cp.args, oid_to_hex(old));
521         /*
522          * If the submodule has modified content, we will diff against the
523          * work tree, under the assumption that the user has asked for the
524          * diff format and wishes to actually see all differences even if they
525          * haven't yet been committed to the submodule yet.
526          */
527         if (!(dirty_submodule & DIRTY_SUBMODULE_MODIFIED))
528                 argv_array_push(&cp.args, oid_to_hex(new));
529
530         if (run_command(&cp))
531                 fprintf(f, "(diff failed)\n");
532
533 done:
534         strbuf_release(&submodule_dir);
535         if (merge_bases)
536                 free_commit_list(merge_bases);
537         if (left)
538                 clear_commit_marks(left, ~0);
539         if (right)
540                 clear_commit_marks(right, ~0);
541 }
542
543 void set_config_fetch_recurse_submodules(int value)
544 {
545         config_fetch_recurse_submodules = value;
546 }
547
548 static int has_remote(const char *refname, const struct object_id *oid,
549                       int flags, void *cb_data)
550 {
551         return 1;
552 }
553
554 static int append_sha1_to_argv(const unsigned char sha1[20], void *data)
555 {
556         struct argv_array *argv = data;
557         argv_array_push(argv, sha1_to_hex(sha1));
558         return 0;
559 }
560
561 static int check_has_commit(const unsigned char sha1[20], void *data)
562 {
563         int *has_commit = data;
564
565         if (!lookup_commit_reference(sha1))
566                 *has_commit = 0;
567
568         return 0;
569 }
570
571 static int submodule_has_commits(const char *path, struct sha1_array *commits)
572 {
573         int has_commit = 1;
574
575         if (add_submodule_odb(path))
576                 return 0;
577
578         sha1_array_for_each_unique(commits, check_has_commit, &has_commit);
579         return has_commit;
580 }
581
582 static int submodule_needs_pushing(const char *path, struct sha1_array *commits)
583 {
584         if (!submodule_has_commits(path, commits))
585                 /*
586                  * NOTE: We do consider it safe to return "no" here. The
587                  * correct answer would be "We do not know" instead of
588                  * "No push needed", but it is quite hard to change
589                  * the submodule pointer without having the submodule
590                  * around. If a user did however change the submodules
591                  * without having the submodule around, this indicates
592                  * an expert who knows what they are doing or a
593                  * maintainer integrating work from other people. In
594                  * both cases it should be safe to skip this check.
595                  */
596                 return 0;
597
598         if (for_each_remote_ref_submodule(path, has_remote, NULL) > 0) {
599                 struct child_process cp = CHILD_PROCESS_INIT;
600                 struct strbuf buf = STRBUF_INIT;
601                 int needs_pushing = 0;
602
603                 argv_array_push(&cp.args, "rev-list");
604                 sha1_array_for_each_unique(commits, append_sha1_to_argv, &cp.args);
605                 argv_array_pushl(&cp.args, "--not", "--remotes", "-n", "1" , NULL);
606
607                 prepare_submodule_repo_env(&cp.env_array);
608                 cp.git_cmd = 1;
609                 cp.no_stdin = 1;
610                 cp.out = -1;
611                 cp.dir = path;
612                 if (start_command(&cp))
613                         die("Could not run 'git rev-list <commits> --not --remotes -n 1' command in submodule %s",
614                                         path);
615                 if (strbuf_read(&buf, cp.out, 41))
616                         needs_pushing = 1;
617                 finish_command(&cp);
618                 close(cp.out);
619                 strbuf_release(&buf);
620                 return needs_pushing;
621         }
622
623         return 0;
624 }
625
626 static struct sha1_array *submodule_commits(struct string_list *submodules,
627                                             const char *path)
628 {
629         struct string_list_item *item;
630
631         item = string_list_insert(submodules, path);
632         if (item->util)
633                 return (struct sha1_array *) item->util;
634
635         /* NEEDSWORK: should we have sha1_array_init()? */
636         item->util = xcalloc(1, sizeof(struct sha1_array));
637         return (struct sha1_array *) item->util;
638 }
639
640 static void collect_submodules_from_diff(struct diff_queue_struct *q,
641                                          struct diff_options *options,
642                                          void *data)
643 {
644         int i;
645         struct string_list *submodules = data;
646
647         for (i = 0; i < q->nr; i++) {
648                 struct diff_filepair *p = q->queue[i];
649                 struct sha1_array *commits;
650                 if (!S_ISGITLINK(p->two->mode))
651                         continue;
652                 commits = submodule_commits(submodules, p->two->path);
653                 sha1_array_append(commits, p->two->oid.hash);
654         }
655 }
656
657 static void find_unpushed_submodule_commits(struct commit *commit,
658                 struct string_list *needs_pushing)
659 {
660         struct rev_info rev;
661
662         init_revisions(&rev, NULL);
663         rev.diffopt.output_format |= DIFF_FORMAT_CALLBACK;
664         rev.diffopt.format_callback = collect_submodules_from_diff;
665         rev.diffopt.format_callback_data = needs_pushing;
666         diff_tree_combined_merge(commit, 1, &rev);
667 }
668
669 static void free_submodules_sha1s(struct string_list *submodules)
670 {
671         struct string_list_item *item;
672         for_each_string_list_item(item, submodules)
673                 sha1_array_clear((struct sha1_array *) item->util);
674         string_list_clear(submodules, 1);
675 }
676
677 int find_unpushed_submodules(struct sha1_array *commits,
678                 const char *remotes_name, struct string_list *needs_pushing)
679 {
680         struct rev_info rev;
681         struct commit *commit;
682         struct string_list submodules = STRING_LIST_INIT_DUP;
683         struct string_list_item *submodule;
684         struct argv_array argv = ARGV_ARRAY_INIT;
685
686         init_revisions(&rev, NULL);
687
688         /* argv.argv[0] will be ignored by setup_revisions */
689         argv_array_push(&argv, "find_unpushed_submodules");
690         sha1_array_for_each_unique(commits, append_sha1_to_argv, &argv);
691         argv_array_push(&argv, "--not");
692         argv_array_pushf(&argv, "--remotes=%s", remotes_name);
693
694         setup_revisions(argv.argc, argv.argv, &rev, NULL);
695         if (prepare_revision_walk(&rev))
696                 die("revision walk setup failed");
697
698         while ((commit = get_revision(&rev)) != NULL)
699                 find_unpushed_submodule_commits(commit, &submodules);
700
701         reset_revision_walk();
702         argv_array_clear(&argv);
703
704         for_each_string_list_item(submodule, &submodules) {
705                 struct sha1_array *commits = (struct sha1_array *) submodule->util;
706
707                 if (submodule_needs_pushing(submodule->string, commits))
708                         string_list_insert(needs_pushing, submodule->string);
709         }
710         free_submodules_sha1s(&submodules);
711
712         return needs_pushing->nr;
713 }
714
715 static int push_submodule(const char *path, int dry_run)
716 {
717         if (add_submodule_odb(path))
718                 return 1;
719
720         if (for_each_remote_ref_submodule(path, has_remote, NULL) > 0) {
721                 struct child_process cp = CHILD_PROCESS_INIT;
722                 argv_array_push(&cp.args, "push");
723                 if (dry_run)
724                         argv_array_push(&cp.args, "--dry-run");
725
726                 prepare_submodule_repo_env(&cp.env_array);
727                 cp.git_cmd = 1;
728                 cp.no_stdin = 1;
729                 cp.dir = path;
730                 if (run_command(&cp))
731                         return 0;
732                 close(cp.out);
733         }
734
735         return 1;
736 }
737
738 int push_unpushed_submodules(struct sha1_array *commits,
739                              const char *remotes_name,
740                              int dry_run)
741 {
742         int i, ret = 1;
743         struct string_list needs_pushing = STRING_LIST_INIT_DUP;
744
745         if (!find_unpushed_submodules(commits, remotes_name, &needs_pushing))
746                 return 1;
747
748         for (i = 0; i < needs_pushing.nr; i++) {
749                 const char *path = needs_pushing.items[i].string;
750                 fprintf(stderr, "Pushing submodule '%s'\n", path);
751                 if (!push_submodule(path, dry_run)) {
752                         fprintf(stderr, "Unable to push submodule '%s'\n", path);
753                         ret = 0;
754                 }
755         }
756
757         string_list_clear(&needs_pushing, 0);
758
759         return ret;
760 }
761
762 static int is_submodule_commit_present(const char *path, unsigned char sha1[20])
763 {
764         int is_present = 0;
765         if (!add_submodule_odb(path) && lookup_commit_reference(sha1)) {
766                 /* Even if the submodule is checked out and the commit is
767                  * present, make sure it is reachable from a ref. */
768                 struct child_process cp = CHILD_PROCESS_INIT;
769                 const char *argv[] = {"rev-list", "-n", "1", NULL, "--not", "--all", NULL};
770                 struct strbuf buf = STRBUF_INIT;
771
772                 argv[3] = sha1_to_hex(sha1);
773                 cp.argv = argv;
774                 prepare_submodule_repo_env(&cp.env_array);
775                 cp.git_cmd = 1;
776                 cp.no_stdin = 1;
777                 cp.dir = path;
778                 if (!capture_command(&cp, &buf, 1024) && !buf.len)
779                         is_present = 1;
780
781                 strbuf_release(&buf);
782         }
783         return is_present;
784 }
785
786 static void submodule_collect_changed_cb(struct diff_queue_struct *q,
787                                          struct diff_options *options,
788                                          void *data)
789 {
790         int i;
791         for (i = 0; i < q->nr; i++) {
792                 struct diff_filepair *p = q->queue[i];
793                 if (!S_ISGITLINK(p->two->mode))
794                         continue;
795
796                 if (S_ISGITLINK(p->one->mode)) {
797                         /* NEEDSWORK: We should honor the name configured in
798                          * the .gitmodules file of the commit we are examining
799                          * here to be able to correctly follow submodules
800                          * being moved around. */
801                         struct string_list_item *path;
802                         path = unsorted_string_list_lookup(&changed_submodule_paths, p->two->path);
803                         if (!path && !is_submodule_commit_present(p->two->path, p->two->oid.hash))
804                                 string_list_append(&changed_submodule_paths, xstrdup(p->two->path));
805                 } else {
806                         /* Submodule is new or was moved here */
807                         /* NEEDSWORK: When the .git directories of submodules
808                          * live inside the superprojects .git directory some
809                          * day we should fetch new submodules directly into
810                          * that location too when config or options request
811                          * that so they can be checked out from there. */
812                         continue;
813                 }
814         }
815 }
816
817 static int add_sha1_to_array(const char *ref, const struct object_id *oid,
818                              int flags, void *data)
819 {
820         sha1_array_append(data, oid->hash);
821         return 0;
822 }
823
824 void check_for_new_submodule_commits(unsigned char new_sha1[20])
825 {
826         if (!initialized_fetch_ref_tips) {
827                 for_each_ref(add_sha1_to_array, &ref_tips_before_fetch);
828                 initialized_fetch_ref_tips = 1;
829         }
830
831         sha1_array_append(&ref_tips_after_fetch, new_sha1);
832 }
833
834 static int add_sha1_to_argv(const unsigned char sha1[20], void *data)
835 {
836         argv_array_push(data, sha1_to_hex(sha1));
837         return 0;
838 }
839
840 static void calculate_changed_submodule_paths(void)
841 {
842         struct rev_info rev;
843         struct commit *commit;
844         struct argv_array argv = ARGV_ARRAY_INIT;
845
846         /* No need to check if there are no submodules configured */
847         if (!submodule_from_path(NULL, NULL))
848                 return;
849
850         init_revisions(&rev, NULL);
851         argv_array_push(&argv, "--"); /* argv[0] program name */
852         sha1_array_for_each_unique(&ref_tips_after_fetch,
853                                    add_sha1_to_argv, &argv);
854         argv_array_push(&argv, "--not");
855         sha1_array_for_each_unique(&ref_tips_before_fetch,
856                                    add_sha1_to_argv, &argv);
857         setup_revisions(argv.argc, argv.argv, &rev, NULL);
858         if (prepare_revision_walk(&rev))
859                 die("revision walk setup failed");
860
861         /*
862          * Collect all submodules (whether checked out or not) for which new
863          * commits have been recorded upstream in "changed_submodule_paths".
864          */
865         while ((commit = get_revision(&rev))) {
866                 struct commit_list *parent = commit->parents;
867                 while (parent) {
868                         struct diff_options diff_opts;
869                         diff_setup(&diff_opts);
870                         DIFF_OPT_SET(&diff_opts, RECURSIVE);
871                         diff_opts.output_format |= DIFF_FORMAT_CALLBACK;
872                         diff_opts.format_callback = submodule_collect_changed_cb;
873                         diff_setup_done(&diff_opts);
874                         diff_tree_sha1(parent->item->object.oid.hash, commit->object.oid.hash, "", &diff_opts);
875                         diffcore_std(&diff_opts);
876                         diff_flush(&diff_opts);
877                         parent = parent->next;
878                 }
879         }
880
881         argv_array_clear(&argv);
882         sha1_array_clear(&ref_tips_before_fetch);
883         sha1_array_clear(&ref_tips_after_fetch);
884         initialized_fetch_ref_tips = 0;
885 }
886
887 struct submodule_parallel_fetch {
888         int count;
889         struct argv_array args;
890         const char *work_tree;
891         const char *prefix;
892         int command_line_option;
893         int quiet;
894         int result;
895 };
896 #define SPF_INIT {0, ARGV_ARRAY_INIT, NULL, NULL, 0, 0, 0}
897
898 static int get_next_submodule(struct child_process *cp,
899                               struct strbuf *err, void *data, void **task_cb)
900 {
901         int ret = 0;
902         struct submodule_parallel_fetch *spf = data;
903
904         for (; spf->count < active_nr; spf->count++) {
905                 struct strbuf submodule_path = STRBUF_INIT;
906                 struct strbuf submodule_git_dir = STRBUF_INIT;
907                 struct strbuf submodule_prefix = STRBUF_INIT;
908                 const struct cache_entry *ce = active_cache[spf->count];
909                 const char *git_dir, *default_argv;
910                 const struct submodule *submodule;
911
912                 if (!S_ISGITLINK(ce->ce_mode))
913                         continue;
914
915                 submodule = submodule_from_path(null_sha1, ce->name);
916                 if (!submodule)
917                         submodule = submodule_from_name(null_sha1, ce->name);
918
919                 default_argv = "yes";
920                 if (spf->command_line_option == RECURSE_SUBMODULES_DEFAULT) {
921                         if (submodule &&
922                             submodule->fetch_recurse !=
923                                                 RECURSE_SUBMODULES_NONE) {
924                                 if (submodule->fetch_recurse ==
925                                                 RECURSE_SUBMODULES_OFF)
926                                         continue;
927                                 if (submodule->fetch_recurse ==
928                                                 RECURSE_SUBMODULES_ON_DEMAND) {
929                                         if (!unsorted_string_list_lookup(&changed_submodule_paths, ce->name))
930                                                 continue;
931                                         default_argv = "on-demand";
932                                 }
933                         } else {
934                                 if ((config_fetch_recurse_submodules == RECURSE_SUBMODULES_OFF) ||
935                                     gitmodules_is_unmerged)
936                                         continue;
937                                 if (config_fetch_recurse_submodules == RECURSE_SUBMODULES_ON_DEMAND) {
938                                         if (!unsorted_string_list_lookup(&changed_submodule_paths, ce->name))
939                                                 continue;
940                                         default_argv = "on-demand";
941                                 }
942                         }
943                 } else if (spf->command_line_option == RECURSE_SUBMODULES_ON_DEMAND) {
944                         if (!unsorted_string_list_lookup(&changed_submodule_paths, ce->name))
945                                 continue;
946                         default_argv = "on-demand";
947                 }
948
949                 strbuf_addf(&submodule_path, "%s/%s", spf->work_tree, ce->name);
950                 strbuf_addf(&submodule_git_dir, "%s/.git", submodule_path.buf);
951                 strbuf_addf(&submodule_prefix, "%s%s/", spf->prefix, ce->name);
952                 git_dir = read_gitfile(submodule_git_dir.buf);
953                 if (!git_dir)
954                         git_dir = submodule_git_dir.buf;
955                 if (is_directory(git_dir)) {
956                         child_process_init(cp);
957                         cp->dir = strbuf_detach(&submodule_path, NULL);
958                         prepare_submodule_repo_env(&cp->env_array);
959                         cp->git_cmd = 1;
960                         if (!spf->quiet)
961                                 strbuf_addf(err, "Fetching submodule %s%s\n",
962                                             spf->prefix, ce->name);
963                         argv_array_init(&cp->args);
964                         argv_array_pushv(&cp->args, spf->args.argv);
965                         argv_array_push(&cp->args, default_argv);
966                         argv_array_push(&cp->args, "--submodule-prefix");
967                         argv_array_push(&cp->args, submodule_prefix.buf);
968                         ret = 1;
969                 }
970                 strbuf_release(&submodule_path);
971                 strbuf_release(&submodule_git_dir);
972                 strbuf_release(&submodule_prefix);
973                 if (ret) {
974                         spf->count++;
975                         return 1;
976                 }
977         }
978         return 0;
979 }
980
981 static int fetch_start_failure(struct strbuf *err,
982                                void *cb, void *task_cb)
983 {
984         struct submodule_parallel_fetch *spf = cb;
985
986         spf->result = 1;
987
988         return 0;
989 }
990
991 static int fetch_finish(int retvalue, struct strbuf *err,
992                         void *cb, void *task_cb)
993 {
994         struct submodule_parallel_fetch *spf = cb;
995
996         if (retvalue)
997                 spf->result = 1;
998
999         return 0;
1000 }
1001
1002 int fetch_populated_submodules(const struct argv_array *options,
1003                                const char *prefix, int command_line_option,
1004                                int quiet, int max_parallel_jobs)
1005 {
1006         int i;
1007         struct submodule_parallel_fetch spf = SPF_INIT;
1008
1009         spf.work_tree = get_git_work_tree();
1010         spf.command_line_option = command_line_option;
1011         spf.quiet = quiet;
1012         spf.prefix = prefix;
1013
1014         if (!spf.work_tree)
1015                 goto out;
1016
1017         if (read_cache() < 0)
1018                 die("index file corrupt");
1019
1020         argv_array_push(&spf.args, "fetch");
1021         for (i = 0; i < options->argc; i++)
1022                 argv_array_push(&spf.args, options->argv[i]);
1023         argv_array_push(&spf.args, "--recurse-submodules-default");
1024         /* default value, "--submodule-prefix" and its value are added later */
1025
1026         if (max_parallel_jobs < 0)
1027                 max_parallel_jobs = parallel_jobs;
1028
1029         calculate_changed_submodule_paths();
1030         run_processes_parallel(max_parallel_jobs,
1031                                get_next_submodule,
1032                                fetch_start_failure,
1033                                fetch_finish,
1034                                &spf);
1035
1036         argv_array_clear(&spf.args);
1037 out:
1038         string_list_clear(&changed_submodule_paths, 1);
1039         return spf.result;
1040 }
1041
1042 unsigned is_submodule_modified(const char *path, int ignore_untracked)
1043 {
1044         ssize_t len;
1045         struct child_process cp = CHILD_PROCESS_INIT;
1046         const char *argv[] = {
1047                 "status",
1048                 "--porcelain",
1049                 NULL,
1050                 NULL,
1051         };
1052         struct strbuf buf = STRBUF_INIT;
1053         unsigned dirty_submodule = 0;
1054         const char *line, *next_line;
1055         const char *git_dir;
1056
1057         strbuf_addf(&buf, "%s/.git", path);
1058         git_dir = read_gitfile(buf.buf);
1059         if (!git_dir)
1060                 git_dir = buf.buf;
1061         if (!is_directory(git_dir)) {
1062                 strbuf_release(&buf);
1063                 /* The submodule is not checked out, so it is not modified */
1064                 return 0;
1065
1066         }
1067         strbuf_reset(&buf);
1068
1069         if (ignore_untracked)
1070                 argv[2] = "-uno";
1071
1072         cp.argv = argv;
1073         prepare_submodule_repo_env(&cp.env_array);
1074         cp.git_cmd = 1;
1075         cp.no_stdin = 1;
1076         cp.out = -1;
1077         cp.dir = path;
1078         if (start_command(&cp))
1079                 die("Could not run 'git status --porcelain' in submodule %s", path);
1080
1081         len = strbuf_read(&buf, cp.out, 1024);
1082         line = buf.buf;
1083         while (len > 2) {
1084                 if ((line[0] == '?') && (line[1] == '?')) {
1085                         dirty_submodule |= DIRTY_SUBMODULE_UNTRACKED;
1086                         if (dirty_submodule & DIRTY_SUBMODULE_MODIFIED)
1087                                 break;
1088                 } else {
1089                         dirty_submodule |= DIRTY_SUBMODULE_MODIFIED;
1090                         if (ignore_untracked ||
1091                             (dirty_submodule & DIRTY_SUBMODULE_UNTRACKED))
1092                                 break;
1093                 }
1094                 next_line = strchr(line, '\n');
1095                 if (!next_line)
1096                         break;
1097                 next_line++;
1098                 len -= (next_line - line);
1099                 line = next_line;
1100         }
1101         close(cp.out);
1102
1103         if (finish_command(&cp))
1104                 die("'git status --porcelain' failed in submodule %s", path);
1105
1106         strbuf_release(&buf);
1107         return dirty_submodule;
1108 }
1109
1110 int submodule_uses_gitfile(const char *path)
1111 {
1112         struct child_process cp = CHILD_PROCESS_INIT;
1113         const char *argv[] = {
1114                 "submodule",
1115                 "foreach",
1116                 "--quiet",
1117                 "--recursive",
1118                 "test -f .git",
1119                 NULL,
1120         };
1121         struct strbuf buf = STRBUF_INIT;
1122         const char *git_dir;
1123
1124         strbuf_addf(&buf, "%s/.git", path);
1125         git_dir = read_gitfile(buf.buf);
1126         if (!git_dir) {
1127                 strbuf_release(&buf);
1128                 return 0;
1129         }
1130         strbuf_release(&buf);
1131
1132         /* Now test that all nested submodules use a gitfile too */
1133         cp.argv = argv;
1134         prepare_submodule_repo_env(&cp.env_array);
1135         cp.git_cmd = 1;
1136         cp.no_stdin = 1;
1137         cp.no_stderr = 1;
1138         cp.no_stdout = 1;
1139         cp.dir = path;
1140         if (run_command(&cp))
1141                 return 0;
1142
1143         return 1;
1144 }
1145
1146 /*
1147  * Check if it is a bad idea to remove a submodule, i.e. if we'd lose data
1148  * when doing so.
1149  *
1150  * Return 1 if we'd lose data, return 0 if the removal is fine,
1151  * and negative values for errors.
1152  */
1153 int bad_to_remove_submodule(const char *path, unsigned flags)
1154 {
1155         ssize_t len;
1156         struct child_process cp = CHILD_PROCESS_INIT;
1157         struct strbuf buf = STRBUF_INIT;
1158         int ret = 0;
1159
1160         if (!file_exists(path) || is_empty_dir(path))
1161                 return 0;
1162
1163         if (!submodule_uses_gitfile(path))
1164                 return 1;
1165
1166         argv_array_pushl(&cp.args, "status", "--porcelain",
1167                                    "--ignore-submodules=none", NULL);
1168
1169         if (flags & SUBMODULE_REMOVAL_IGNORE_UNTRACKED)
1170                 argv_array_push(&cp.args, "-uno");
1171         else
1172                 argv_array_push(&cp.args, "-uall");
1173
1174         if (!(flags & SUBMODULE_REMOVAL_IGNORE_IGNORED_UNTRACKED))
1175                 argv_array_push(&cp.args, "--ignored");
1176
1177         prepare_submodule_repo_env(&cp.env_array);
1178         cp.git_cmd = 1;
1179         cp.no_stdin = 1;
1180         cp.out = -1;
1181         cp.dir = path;
1182         if (start_command(&cp)) {
1183                 if (flags & SUBMODULE_REMOVAL_DIE_ON_ERROR)
1184                         die(_("could not start 'git status in submodule '%s'"),
1185                                 path);
1186                 ret = -1;
1187                 goto out;
1188         }
1189
1190         len = strbuf_read(&buf, cp.out, 1024);
1191         if (len > 2)
1192                 ret = 1;
1193         close(cp.out);
1194
1195         if (finish_command(&cp)) {
1196                 if (flags & SUBMODULE_REMOVAL_DIE_ON_ERROR)
1197                         die(_("could not run 'git status in submodule '%s'"),
1198                                 path);
1199                 ret = -1;
1200         }
1201 out:
1202         strbuf_release(&buf);
1203         return ret;
1204 }
1205
1206 static int find_first_merges(struct object_array *result, const char *path,
1207                 struct commit *a, struct commit *b)
1208 {
1209         int i, j;
1210         struct object_array merges = OBJECT_ARRAY_INIT;
1211         struct commit *commit;
1212         int contains_another;
1213
1214         char merged_revision[42];
1215         const char *rev_args[] = { "rev-list", "--merges", "--ancestry-path",
1216                                    "--all", merged_revision, NULL };
1217         struct rev_info revs;
1218         struct setup_revision_opt rev_opts;
1219
1220         memset(result, 0, sizeof(struct object_array));
1221         memset(&rev_opts, 0, sizeof(rev_opts));
1222
1223         /* get all revisions that merge commit a */
1224         snprintf(merged_revision, sizeof(merged_revision), "^%s",
1225                         oid_to_hex(&a->object.oid));
1226         init_revisions(&revs, NULL);
1227         rev_opts.submodule = path;
1228         setup_revisions(ARRAY_SIZE(rev_args)-1, rev_args, &revs, &rev_opts);
1229
1230         /* save all revisions from the above list that contain b */
1231         if (prepare_revision_walk(&revs))
1232                 die("revision walk setup failed");
1233         while ((commit = get_revision(&revs)) != NULL) {
1234                 struct object *o = &(commit->object);
1235                 if (in_merge_bases(b, commit))
1236                         add_object_array(o, NULL, &merges);
1237         }
1238         reset_revision_walk();
1239
1240         /* Now we've got all merges that contain a and b. Prune all
1241          * merges that contain another found merge and save them in
1242          * result.
1243          */
1244         for (i = 0; i < merges.nr; i++) {
1245                 struct commit *m1 = (struct commit *) merges.objects[i].item;
1246
1247                 contains_another = 0;
1248                 for (j = 0; j < merges.nr; j++) {
1249                         struct commit *m2 = (struct commit *) merges.objects[j].item;
1250                         if (i != j && in_merge_bases(m2, m1)) {
1251                                 contains_another = 1;
1252                                 break;
1253                         }
1254                 }
1255
1256                 if (!contains_another)
1257                         add_object_array(merges.objects[i].item, NULL, result);
1258         }
1259
1260         free(merges.objects);
1261         return result->nr;
1262 }
1263
1264 static void print_commit(struct commit *commit)
1265 {
1266         struct strbuf sb = STRBUF_INIT;
1267         struct pretty_print_context ctx = {0};
1268         ctx.date_mode.type = DATE_NORMAL;
1269         format_commit_message(commit, " %h: %m %s", &sb, &ctx);
1270         fprintf(stderr, "%s\n", sb.buf);
1271         strbuf_release(&sb);
1272 }
1273
1274 #define MERGE_WARNING(path, msg) \
1275         warning("Failed to merge submodule %s (%s)", path, msg);
1276
1277 int merge_submodule(unsigned char result[20], const char *path,
1278                     const unsigned char base[20], const unsigned char a[20],
1279                     const unsigned char b[20], int search)
1280 {
1281         struct commit *commit_base, *commit_a, *commit_b;
1282         int parent_count;
1283         struct object_array merges;
1284
1285         int i;
1286
1287         /* store a in result in case we fail */
1288         hashcpy(result, a);
1289
1290         /* we can not handle deletion conflicts */
1291         if (is_null_sha1(base))
1292                 return 0;
1293         if (is_null_sha1(a))
1294                 return 0;
1295         if (is_null_sha1(b))
1296                 return 0;
1297
1298         if (add_submodule_odb(path)) {
1299                 MERGE_WARNING(path, "not checked out");
1300                 return 0;
1301         }
1302
1303         if (!(commit_base = lookup_commit_reference(base)) ||
1304             !(commit_a = lookup_commit_reference(a)) ||
1305             !(commit_b = lookup_commit_reference(b))) {
1306                 MERGE_WARNING(path, "commits not present");
1307                 return 0;
1308         }
1309
1310         /* check whether both changes are forward */
1311         if (!in_merge_bases(commit_base, commit_a) ||
1312             !in_merge_bases(commit_base, commit_b)) {
1313                 MERGE_WARNING(path, "commits don't follow merge-base");
1314                 return 0;
1315         }
1316
1317         /* Case #1: a is contained in b or vice versa */
1318         if (in_merge_bases(commit_a, commit_b)) {
1319                 hashcpy(result, b);
1320                 return 1;
1321         }
1322         if (in_merge_bases(commit_b, commit_a)) {
1323                 hashcpy(result, a);
1324                 return 1;
1325         }
1326
1327         /*
1328          * Case #2: There are one or more merges that contain a and b in
1329          * the submodule. If there is only one, then present it as a
1330          * suggestion to the user, but leave it marked unmerged so the
1331          * user needs to confirm the resolution.
1332          */
1333
1334         /* Skip the search if makes no sense to the calling context.  */
1335         if (!search)
1336                 return 0;
1337
1338         /* find commit which merges them */
1339         parent_count = find_first_merges(&merges, path, commit_a, commit_b);
1340         switch (parent_count) {
1341         case 0:
1342                 MERGE_WARNING(path, "merge following commits not found");
1343                 break;
1344
1345         case 1:
1346                 MERGE_WARNING(path, "not fast-forward");
1347                 fprintf(stderr, "Found a possible merge resolution "
1348                                 "for the submodule:\n");
1349                 print_commit((struct commit *) merges.objects[0].item);
1350                 fprintf(stderr,
1351                         "If this is correct simply add it to the index "
1352                         "for example\n"
1353                         "by using:\n\n"
1354                         "  git update-index --cacheinfo 160000 %s \"%s\"\n\n"
1355                         "which will accept this suggestion.\n",
1356                         oid_to_hex(&merges.objects[0].item->oid), path);
1357                 break;
1358
1359         default:
1360                 MERGE_WARNING(path, "multiple merges found");
1361                 for (i = 0; i < merges.nr; i++)
1362                         print_commit((struct commit *) merges.objects[i].item);
1363         }
1364
1365         free(merges.objects);
1366         return 0;
1367 }
1368
1369 int parallel_submodules(void)
1370 {
1371         return parallel_jobs;
1372 }
1373
1374 void prepare_submodule_repo_env(struct argv_array *out)
1375 {
1376         const char * const *var;
1377
1378         for (var = local_repo_env; *var; var++) {
1379                 if (strcmp(*var, CONFIG_DATA_ENVIRONMENT))
1380                         argv_array_push(out, *var);
1381         }
1382         argv_array_pushf(out, "%s=%s", GIT_DIR_ENVIRONMENT,
1383                          DEFAULT_GIT_DIR_ENVIRONMENT);
1384 }
1385
1386 /*
1387  * Embeds a single submodules git directory into the superprojects git dir,
1388  * non recursively.
1389  */
1390 static void relocate_single_git_dir_into_superproject(const char *prefix,
1391                                                       const char *path)
1392 {
1393         char *old_git_dir = NULL, *real_old_git_dir = NULL, *real_new_git_dir = NULL;
1394         const char *new_git_dir;
1395         const struct submodule *sub;
1396
1397         if (submodule_uses_worktrees(path))
1398                 die(_("relocate_gitdir for submodule '%s' with "
1399                       "more than one worktree not supported"), path);
1400
1401         old_git_dir = xstrfmt("%s/.git", path);
1402         if (read_gitfile(old_git_dir))
1403                 /* If it is an actual gitfile, it doesn't need migration. */
1404                 return;
1405
1406         real_old_git_dir = real_pathdup(old_git_dir);
1407
1408         sub = submodule_from_path(null_sha1, path);
1409         if (!sub)
1410                 die(_("could not lookup name for submodule '%s'"), path);
1411
1412         new_git_dir = git_path("modules/%s", sub->name);
1413         if (safe_create_leading_directories_const(new_git_dir) < 0)
1414                 die(_("could not create directory '%s'"), new_git_dir);
1415         real_new_git_dir = real_pathdup(new_git_dir);
1416
1417         if (!prefix)
1418                 prefix = get_super_prefix();
1419
1420         fprintf(stderr, _("Migrating git directory of '%s%s' from\n'%s' to\n'%s'\n"),
1421                 prefix ? prefix : "", path,
1422                 real_old_git_dir, real_new_git_dir);
1423
1424         relocate_gitdir(path, real_old_git_dir, real_new_git_dir);
1425
1426         free(old_git_dir);
1427         free(real_old_git_dir);
1428         free(real_new_git_dir);
1429 }
1430
1431 /*
1432  * Migrate the git directory of the submodule given by path from
1433  * having its git directory within the working tree to the git dir nested
1434  * in its superprojects git dir under modules/.
1435  */
1436 void absorb_git_dir_into_superproject(const char *prefix,
1437                                       const char *path,
1438                                       unsigned flags)
1439 {
1440         const char *sub_git_dir, *v;
1441         char *real_sub_git_dir = NULL, *real_common_git_dir = NULL;
1442         struct strbuf gitdir = STRBUF_INIT;
1443
1444         strbuf_addf(&gitdir, "%s/.git", path);
1445         sub_git_dir = resolve_gitdir(gitdir.buf);
1446
1447         /* Not populated? */
1448         if (!sub_git_dir)
1449                 goto out;
1450
1451         /* Is it already absorbed into the superprojects git dir? */
1452         real_sub_git_dir = real_pathdup(sub_git_dir);
1453         real_common_git_dir = real_pathdup(get_git_common_dir());
1454         if (!skip_prefix(real_sub_git_dir, real_common_git_dir, &v))
1455                 relocate_single_git_dir_into_superproject(prefix, path);
1456
1457         if (flags & ABSORB_GITDIR_RECURSE_SUBMODULES) {
1458                 struct child_process cp = CHILD_PROCESS_INIT;
1459                 struct strbuf sb = STRBUF_INIT;
1460
1461                 if (flags & ~ABSORB_GITDIR_RECURSE_SUBMODULES)
1462                         die("BUG: we don't know how to pass the flags down?");
1463
1464                 if (get_super_prefix())
1465                         strbuf_addstr(&sb, get_super_prefix());
1466                 strbuf_addstr(&sb, path);
1467                 strbuf_addch(&sb, '/');
1468
1469                 cp.dir = path;
1470                 cp.git_cmd = 1;
1471                 cp.no_stdin = 1;
1472                 argv_array_pushl(&cp.args, "--super-prefix", sb.buf,
1473                                            "submodule--helper",
1474                                            "absorb-git-dirs", NULL);
1475                 prepare_submodule_repo_env(&cp.env_array);
1476                 if (run_command(&cp))
1477                         die(_("could not recurse into submodule '%s'"), path);
1478
1479                 strbuf_release(&sb);
1480         }
1481
1482 out:
1483         strbuf_release(&gitdir);
1484         free(real_sub_git_dir);
1485         free(real_common_git_dir);
1486 }