submodule: rename free_submodules_sha1s()
[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 "remote.h"
18 #include "worktree.h"
19
20 static int config_fetch_recurse_submodules = RECURSE_SUBMODULES_ON_DEMAND;
21 static int config_update_recurse_submodules = RECURSE_SUBMODULES_DEFAULT;
22 static int parallel_jobs = 1;
23 static struct string_list changed_submodule_paths = STRING_LIST_INIT_NODUP;
24 static int initialized_fetch_ref_tips;
25 static struct oid_array ref_tips_before_fetch;
26 static struct oid_array ref_tips_after_fetch;
27
28 /*
29  * The following flag is set if the .gitmodules file is unmerged. We then
30  * disable recursion for all submodules where .git/config doesn't have a
31  * matching config entry because we can't guess what might be configured in
32  * .gitmodules unless the user resolves the conflict. When a command line
33  * option is given (which always overrides configuration) this flag will be
34  * ignored.
35  */
36 static int gitmodules_is_unmerged;
37
38 /*
39  * This flag is set if the .gitmodules file had unstaged modifications on
40  * startup. This must be checked before allowing modifications to the
41  * .gitmodules file with the intention to stage them later, because when
42  * continuing we would stage the modifications the user didn't stage herself
43  * too. That might change in a future version when we learn to stage the
44  * changes we do ourselves without staging any previous modifications.
45  */
46 static int gitmodules_is_modified;
47
48 int is_staging_gitmodules_ok(void)
49 {
50         return !gitmodules_is_modified;
51 }
52
53 /*
54  * Try to update the "path" entry in the "submodule.<name>" section of the
55  * .gitmodules file. Return 0 only if a .gitmodules file was found, a section
56  * with the correct path=<oldpath> setting was found and we could update it.
57  */
58 int update_path_in_gitmodules(const char *oldpath, const char *newpath)
59 {
60         struct strbuf entry = STRBUF_INIT;
61         const struct submodule *submodule;
62
63         if (!file_exists(".gitmodules")) /* Do nothing without .gitmodules */
64                 return -1;
65
66         if (gitmodules_is_unmerged)
67                 die(_("Cannot change unmerged .gitmodules, resolve merge conflicts first"));
68
69         submodule = submodule_from_path(null_sha1, oldpath);
70         if (!submodule || !submodule->name) {
71                 warning(_("Could not find section in .gitmodules where path=%s"), oldpath);
72                 return -1;
73         }
74         strbuf_addstr(&entry, "submodule.");
75         strbuf_addstr(&entry, submodule->name);
76         strbuf_addstr(&entry, ".path");
77         if (git_config_set_in_file_gently(".gitmodules", entry.buf, newpath) < 0) {
78                 /* Maybe the user already did that, don't error out here */
79                 warning(_("Could not update .gitmodules entry %s"), entry.buf);
80                 strbuf_release(&entry);
81                 return -1;
82         }
83         strbuf_release(&entry);
84         return 0;
85 }
86
87 /*
88  * Try to remove the "submodule.<name>" section from .gitmodules where the given
89  * path is configured. Return 0 only if a .gitmodules file was found, a section
90  * with the correct path=<path> setting was found and we could remove it.
91  */
92 int remove_path_from_gitmodules(const char *path)
93 {
94         struct strbuf sect = STRBUF_INIT;
95         const struct submodule *submodule;
96
97         if (!file_exists(".gitmodules")) /* Do nothing without .gitmodules */
98                 return -1;
99
100         if (gitmodules_is_unmerged)
101                 die(_("Cannot change unmerged .gitmodules, resolve merge conflicts first"));
102
103         submodule = submodule_from_path(null_sha1, path);
104         if (!submodule || !submodule->name) {
105                 warning(_("Could not find section in .gitmodules where path=%s"), path);
106                 return -1;
107         }
108         strbuf_addstr(&sect, "submodule.");
109         strbuf_addstr(&sect, submodule->name);
110         if (git_config_rename_section_in_file(".gitmodules", sect.buf, NULL) < 0) {
111                 /* Maybe the user already did that, don't error out here */
112                 warning(_("Could not remove .gitmodules entry for %s"), path);
113                 strbuf_release(&sect);
114                 return -1;
115         }
116         strbuf_release(&sect);
117         return 0;
118 }
119
120 void stage_updated_gitmodules(void)
121 {
122         if (add_file_to_cache(".gitmodules", 0))
123                 die(_("staging updated .gitmodules failed"));
124 }
125
126 static int add_submodule_odb(const char *path)
127 {
128         struct strbuf objects_directory = STRBUF_INIT;
129         int ret = 0;
130
131         ret = strbuf_git_path_submodule(&objects_directory, path, "objects/");
132         if (ret)
133                 goto done;
134         if (!is_directory(objects_directory.buf)) {
135                 ret = -1;
136                 goto done;
137         }
138         add_to_alternates_memory(objects_directory.buf);
139 done:
140         strbuf_release(&objects_directory);
141         return ret;
142 }
143
144 void set_diffopt_flags_from_submodule_config(struct diff_options *diffopt,
145                                              const char *path)
146 {
147         const struct submodule *submodule = submodule_from_path(null_sha1, path);
148         if (submodule) {
149                 if (submodule->ignore)
150                         handle_ignore_submodules_arg(diffopt, submodule->ignore);
151                 else if (gitmodules_is_unmerged)
152                         DIFF_OPT_SET(diffopt, IGNORE_SUBMODULES);
153         }
154 }
155
156 int submodule_config(const char *var, const char *value, void *cb)
157 {
158         if (!strcmp(var, "submodule.fetchjobs")) {
159                 parallel_jobs = git_config_int(var, value);
160                 if (parallel_jobs < 0)
161                         die(_("negative values not allowed for submodule.fetchJobs"));
162                 return 0;
163         } else if (starts_with(var, "submodule."))
164                 return parse_submodule_config_option(var, value);
165         else if (!strcmp(var, "fetch.recursesubmodules")) {
166                 config_fetch_recurse_submodules = parse_fetch_recurse_submodules_arg(var, value);
167                 return 0;
168         }
169         return 0;
170 }
171
172 void gitmodules_config(void)
173 {
174         const char *work_tree = get_git_work_tree();
175         if (work_tree) {
176                 struct strbuf gitmodules_path = STRBUF_INIT;
177                 int pos;
178                 strbuf_addstr(&gitmodules_path, work_tree);
179                 strbuf_addstr(&gitmodules_path, "/.gitmodules");
180                 if (read_cache() < 0)
181                         die("index file corrupt");
182                 pos = cache_name_pos(".gitmodules", 11);
183                 if (pos < 0) { /* .gitmodules not found or isn't merged */
184                         pos = -1 - pos;
185                         if (active_nr > pos) {  /* there is a .gitmodules */
186                                 const struct cache_entry *ce = active_cache[pos];
187                                 if (ce_namelen(ce) == 11 &&
188                                     !memcmp(ce->name, ".gitmodules", 11))
189                                         gitmodules_is_unmerged = 1;
190                         }
191                 } else if (pos < active_nr) {
192                         struct stat st;
193                         if (lstat(".gitmodules", &st) == 0 &&
194                             ce_match_stat(active_cache[pos], &st, 0) & DATA_CHANGED)
195                                 gitmodules_is_modified = 1;
196                 }
197
198                 if (!gitmodules_is_unmerged)
199                         git_config_from_file(submodule_config, gitmodules_path.buf, NULL);
200                 strbuf_release(&gitmodules_path);
201         }
202 }
203
204 void gitmodules_config_sha1(const unsigned char *commit_sha1)
205 {
206         struct strbuf rev = STRBUF_INIT;
207         unsigned char sha1[20];
208
209         if (gitmodule_sha1_from_commit(commit_sha1, sha1, &rev)) {
210                 git_config_from_blob_sha1(submodule_config, rev.buf,
211                                           sha1, NULL);
212         }
213         strbuf_release(&rev);
214 }
215
216 /*
217  * NEEDSWORK: With the addition of different configuration options to determine
218  * if a submodule is of interests, the validity of this function's name comes
219  * into question.  Once the dust has settled and more concrete terminology is
220  * decided upon, come up with a more proper name for this function.  One
221  * potential candidate could be 'is_submodule_active()'.
222  *
223  * Determine if a submodule has been initialized at a given 'path'
224  */
225 int is_submodule_initialized(const char *path)
226 {
227         int ret = 0;
228         char *key = NULL;
229         char *value = NULL;
230         const struct string_list *sl;
231         const struct submodule *module = submodule_from_path(null_sha1, path);
232
233         /* early return if there isn't a path->module mapping */
234         if (!module)
235                 return 0;
236
237         /* submodule.<name>.active is set */
238         key = xstrfmt("submodule.%s.active", module->name);
239         if (!git_config_get_bool(key, &ret)) {
240                 free(key);
241                 return ret;
242         }
243         free(key);
244
245         /* submodule.active is set */
246         sl = git_config_get_value_multi("submodule.active");
247         if (sl) {
248                 struct pathspec ps;
249                 struct argv_array args = ARGV_ARRAY_INIT;
250                 const struct string_list_item *item;
251
252                 for_each_string_list_item(item, sl) {
253                         argv_array_push(&args, item->string);
254                 }
255
256                 parse_pathspec(&ps, 0, 0, NULL, args.argv);
257                 ret = match_pathspec(&ps, path, strlen(path), 0, NULL, 1);
258
259                 argv_array_clear(&args);
260                 clear_pathspec(&ps);
261                 return ret;
262         }
263
264         /* fallback to checking if the URL is set */
265         key = xstrfmt("submodule.%s.url", module->name);
266         ret = !git_config_get_string(key, &value);
267
268         free(value);
269         free(key);
270         return ret;
271 }
272
273 int is_submodule_populated_gently(const char *path, int *return_error_code)
274 {
275         int ret = 0;
276         char *gitdir = xstrfmt("%s/.git", path);
277
278         if (resolve_gitdir_gently(gitdir, return_error_code))
279                 ret = 1;
280
281         free(gitdir);
282         return ret;
283 }
284
285 int parse_submodule_update_strategy(const char *value,
286                 struct submodule_update_strategy *dst)
287 {
288         free((void*)dst->command);
289         dst->command = NULL;
290         if (!strcmp(value, "none"))
291                 dst->type = SM_UPDATE_NONE;
292         else if (!strcmp(value, "checkout"))
293                 dst->type = SM_UPDATE_CHECKOUT;
294         else if (!strcmp(value, "rebase"))
295                 dst->type = SM_UPDATE_REBASE;
296         else if (!strcmp(value, "merge"))
297                 dst->type = SM_UPDATE_MERGE;
298         else if (skip_prefix(value, "!", &value)) {
299                 dst->type = SM_UPDATE_COMMAND;
300                 dst->command = xstrdup(value);
301         } else
302                 return -1;
303         return 0;
304 }
305
306 const char *submodule_strategy_to_string(const struct submodule_update_strategy *s)
307 {
308         struct strbuf sb = STRBUF_INIT;
309         switch (s->type) {
310         case SM_UPDATE_CHECKOUT:
311                 return "checkout";
312         case SM_UPDATE_MERGE:
313                 return "merge";
314         case SM_UPDATE_REBASE:
315                 return "rebase";
316         case SM_UPDATE_NONE:
317                 return "none";
318         case SM_UPDATE_UNSPECIFIED:
319                 return NULL;
320         case SM_UPDATE_COMMAND:
321                 strbuf_addf(&sb, "!%s", s->command);
322                 return strbuf_detach(&sb, NULL);
323         }
324         return NULL;
325 }
326
327 void handle_ignore_submodules_arg(struct diff_options *diffopt,
328                                   const char *arg)
329 {
330         DIFF_OPT_CLR(diffopt, IGNORE_SUBMODULES);
331         DIFF_OPT_CLR(diffopt, IGNORE_UNTRACKED_IN_SUBMODULES);
332         DIFF_OPT_CLR(diffopt, IGNORE_DIRTY_SUBMODULES);
333
334         if (!strcmp(arg, "all"))
335                 DIFF_OPT_SET(diffopt, IGNORE_SUBMODULES);
336         else if (!strcmp(arg, "untracked"))
337                 DIFF_OPT_SET(diffopt, IGNORE_UNTRACKED_IN_SUBMODULES);
338         else if (!strcmp(arg, "dirty"))
339                 DIFF_OPT_SET(diffopt, IGNORE_DIRTY_SUBMODULES);
340         else if (strcmp(arg, "none"))
341                 die("bad --ignore-submodules argument: %s", arg);
342 }
343
344 static int prepare_submodule_summary(struct rev_info *rev, const char *path,
345                 struct commit *left, struct commit *right,
346                 struct commit_list *merge_bases)
347 {
348         struct commit_list *list;
349
350         init_revisions(rev, NULL);
351         setup_revisions(0, NULL, rev, NULL);
352         rev->left_right = 1;
353         rev->first_parent_only = 1;
354         left->object.flags |= SYMMETRIC_LEFT;
355         add_pending_object(rev, &left->object, path);
356         add_pending_object(rev, &right->object, path);
357         for (list = merge_bases; list; list = list->next) {
358                 list->item->object.flags |= UNINTERESTING;
359                 add_pending_object(rev, &list->item->object,
360                         oid_to_hex(&list->item->object.oid));
361         }
362         return prepare_revision_walk(rev);
363 }
364
365 static void print_submodule_summary(struct rev_info *rev, FILE *f,
366                 const char *line_prefix,
367                 const char *del, const char *add, const char *reset)
368 {
369         static const char format[] = "  %m %s";
370         struct strbuf sb = STRBUF_INIT;
371         struct commit *commit;
372
373         while ((commit = get_revision(rev))) {
374                 struct pretty_print_context ctx = {0};
375                 ctx.date_mode = rev->date_mode;
376                 ctx.output_encoding = get_log_output_encoding();
377                 strbuf_setlen(&sb, 0);
378                 strbuf_addstr(&sb, line_prefix);
379                 if (commit->object.flags & SYMMETRIC_LEFT) {
380                         if (del)
381                                 strbuf_addstr(&sb, del);
382                 }
383                 else if (add)
384                         strbuf_addstr(&sb, add);
385                 format_commit_message(commit, format, &sb, &ctx);
386                 if (reset)
387                         strbuf_addstr(&sb, reset);
388                 strbuf_addch(&sb, '\n');
389                 fprintf(f, "%s", sb.buf);
390         }
391         strbuf_release(&sb);
392 }
393
394 static void prepare_submodule_repo_env_no_git_dir(struct argv_array *out)
395 {
396         const char * const *var;
397
398         for (var = local_repo_env; *var; var++) {
399                 if (strcmp(*var, CONFIG_DATA_ENVIRONMENT))
400                         argv_array_push(out, *var);
401         }
402 }
403
404 void prepare_submodule_repo_env(struct argv_array *out)
405 {
406         prepare_submodule_repo_env_no_git_dir(out);
407         argv_array_pushf(out, "%s=%s", GIT_DIR_ENVIRONMENT,
408                          DEFAULT_GIT_DIR_ENVIRONMENT);
409 }
410
411 /* Helper function to display the submodule header line prior to the full
412  * summary output. If it can locate the submodule objects directory it will
413  * attempt to lookup both the left and right commits and put them into the
414  * left and right pointers.
415  */
416 static void show_submodule_header(FILE *f, const char *path,
417                 const char *line_prefix,
418                 struct object_id *one, struct object_id *two,
419                 unsigned dirty_submodule, const char *meta,
420                 const char *reset,
421                 struct commit **left, struct commit **right,
422                 struct commit_list **merge_bases)
423 {
424         const char *message = NULL;
425         struct strbuf sb = STRBUF_INIT;
426         int fast_forward = 0, fast_backward = 0;
427
428         if (dirty_submodule & DIRTY_SUBMODULE_UNTRACKED)
429                 fprintf(f, "%sSubmodule %s contains untracked content\n",
430                         line_prefix, path);
431         if (dirty_submodule & DIRTY_SUBMODULE_MODIFIED)
432                 fprintf(f, "%sSubmodule %s contains modified content\n",
433                         line_prefix, path);
434
435         if (is_null_oid(one))
436                 message = "(new submodule)";
437         else if (is_null_oid(two))
438                 message = "(submodule deleted)";
439
440         if (add_submodule_odb(path)) {
441                 if (!message)
442                         message = "(not initialized)";
443                 goto output_header;
444         }
445
446         /*
447          * Attempt to lookup the commit references, and determine if this is
448          * a fast forward or fast backwards update.
449          */
450         *left = lookup_commit_reference(one->hash);
451         *right = lookup_commit_reference(two->hash);
452
453         /*
454          * Warn about missing commits in the submodule project, but only if
455          * they aren't null.
456          */
457         if ((!is_null_oid(one) && !*left) ||
458              (!is_null_oid(two) && !*right))
459                 message = "(commits not present)";
460
461         *merge_bases = get_merge_bases(*left, *right);
462         if (*merge_bases) {
463                 if ((*merge_bases)->item == *left)
464                         fast_forward = 1;
465                 else if ((*merge_bases)->item == *right)
466                         fast_backward = 1;
467         }
468
469         if (!oidcmp(one, two)) {
470                 strbuf_release(&sb);
471                 return;
472         }
473
474 output_header:
475         strbuf_addf(&sb, "%s%sSubmodule %s ", line_prefix, meta, path);
476         strbuf_add_unique_abbrev(&sb, one->hash, DEFAULT_ABBREV);
477         strbuf_addstr(&sb, (fast_backward || fast_forward) ? ".." : "...");
478         strbuf_add_unique_abbrev(&sb, two->hash, DEFAULT_ABBREV);
479         if (message)
480                 strbuf_addf(&sb, " %s%s\n", message, reset);
481         else
482                 strbuf_addf(&sb, "%s:%s\n", fast_backward ? " (rewind)" : "", reset);
483         fwrite(sb.buf, sb.len, 1, f);
484
485         strbuf_release(&sb);
486 }
487
488 void show_submodule_summary(FILE *f, const char *path,
489                 const char *line_prefix,
490                 struct object_id *one, struct object_id *two,
491                 unsigned dirty_submodule, const char *meta,
492                 const char *del, const char *add, const char *reset)
493 {
494         struct rev_info rev;
495         struct commit *left = NULL, *right = NULL;
496         struct commit_list *merge_bases = NULL;
497
498         show_submodule_header(f, path, line_prefix, one, two, dirty_submodule,
499                               meta, reset, &left, &right, &merge_bases);
500
501         /*
502          * If we don't have both a left and a right pointer, there is no
503          * reason to try and display a summary. The header line should contain
504          * all the information the user needs.
505          */
506         if (!left || !right)
507                 goto out;
508
509         /* Treat revision walker failure the same as missing commits */
510         if (prepare_submodule_summary(&rev, path, left, right, merge_bases)) {
511                 fprintf(f, "%s(revision walker failed)\n", line_prefix);
512                 goto out;
513         }
514
515         print_submodule_summary(&rev, f, line_prefix, del, add, reset);
516
517 out:
518         if (merge_bases)
519                 free_commit_list(merge_bases);
520         clear_commit_marks(left, ~0);
521         clear_commit_marks(right, ~0);
522 }
523
524 void show_submodule_inline_diff(FILE *f, const char *path,
525                 const char *line_prefix,
526                 struct object_id *one, struct object_id *two,
527                 unsigned dirty_submodule, const char *meta,
528                 const char *del, const char *add, const char *reset,
529                 const struct diff_options *o)
530 {
531         const struct object_id *old = &empty_tree_oid, *new = &empty_tree_oid;
532         struct commit *left = NULL, *right = NULL;
533         struct commit_list *merge_bases = NULL;
534         struct strbuf submodule_dir = STRBUF_INIT;
535         struct child_process cp = CHILD_PROCESS_INIT;
536
537         show_submodule_header(f, path, line_prefix, one, two, dirty_submodule,
538                               meta, reset, &left, &right, &merge_bases);
539
540         /* We need a valid left and right commit to display a difference */
541         if (!(left || is_null_oid(one)) ||
542             !(right || is_null_oid(two)))
543                 goto done;
544
545         if (left)
546                 old = one;
547         if (right)
548                 new = two;
549
550         fflush(f);
551         cp.git_cmd = 1;
552         cp.dir = path;
553         cp.out = dup(fileno(f));
554         cp.no_stdin = 1;
555
556         /* TODO: other options may need to be passed here. */
557         argv_array_push(&cp.args, "diff");
558         argv_array_pushf(&cp.args, "--line-prefix=%s", line_prefix);
559         if (DIFF_OPT_TST(o, REVERSE_DIFF)) {
560                 argv_array_pushf(&cp.args, "--src-prefix=%s%s/",
561                                  o->b_prefix, path);
562                 argv_array_pushf(&cp.args, "--dst-prefix=%s%s/",
563                                  o->a_prefix, path);
564         } else {
565                 argv_array_pushf(&cp.args, "--src-prefix=%s%s/",
566                                  o->a_prefix, path);
567                 argv_array_pushf(&cp.args, "--dst-prefix=%s%s/",
568                                  o->b_prefix, path);
569         }
570         argv_array_push(&cp.args, oid_to_hex(old));
571         /*
572          * If the submodule has modified content, we will diff against the
573          * work tree, under the assumption that the user has asked for the
574          * diff format and wishes to actually see all differences even if they
575          * haven't yet been committed to the submodule yet.
576          */
577         if (!(dirty_submodule & DIRTY_SUBMODULE_MODIFIED))
578                 argv_array_push(&cp.args, oid_to_hex(new));
579
580         prepare_submodule_repo_env(&cp.env_array);
581         if (run_command(&cp))
582                 fprintf(f, "(diff failed)\n");
583
584 done:
585         strbuf_release(&submodule_dir);
586         if (merge_bases)
587                 free_commit_list(merge_bases);
588         if (left)
589                 clear_commit_marks(left, ~0);
590         if (right)
591                 clear_commit_marks(right, ~0);
592 }
593
594 void set_config_fetch_recurse_submodules(int value)
595 {
596         config_fetch_recurse_submodules = value;
597 }
598
599 void set_config_update_recurse_submodules(int value)
600 {
601         config_update_recurse_submodules = value;
602 }
603
604 int should_update_submodules(void)
605 {
606         return config_update_recurse_submodules == RECURSE_SUBMODULES_ON;
607 }
608
609 const struct submodule *submodule_from_ce(const struct cache_entry *ce)
610 {
611         if (!S_ISGITLINK(ce->ce_mode))
612                 return NULL;
613
614         if (!should_update_submodules())
615                 return NULL;
616
617         return submodule_from_path(null_sha1, ce->name);
618 }
619
620 static int has_remote(const char *refname, const struct object_id *oid,
621                       int flags, void *cb_data)
622 {
623         return 1;
624 }
625
626 static int append_oid_to_argv(const struct object_id *oid, void *data)
627 {
628         struct argv_array *argv = data;
629         argv_array_push(argv, oid_to_hex(oid));
630         return 0;
631 }
632
633 static int check_has_commit(const struct object_id *oid, void *data)
634 {
635         int *has_commit = data;
636
637         if (!lookup_commit_reference(oid->hash))
638                 *has_commit = 0;
639
640         return 0;
641 }
642
643 static int submodule_has_commits(const char *path, struct oid_array *commits)
644 {
645         int has_commit = 1;
646
647         if (add_submodule_odb(path))
648                 return 0;
649
650         oid_array_for_each_unique(commits, check_has_commit, &has_commit);
651         return has_commit;
652 }
653
654 static int submodule_needs_pushing(const char *path, struct oid_array *commits)
655 {
656         if (!submodule_has_commits(path, commits))
657                 /*
658                  * NOTE: We do consider it safe to return "no" here. The
659                  * correct answer would be "We do not know" instead of
660                  * "No push needed", but it is quite hard to change
661                  * the submodule pointer without having the submodule
662                  * around. If a user did however change the submodules
663                  * without having the submodule around, this indicates
664                  * an expert who knows what they are doing or a
665                  * maintainer integrating work from other people. In
666                  * both cases it should be safe to skip this check.
667                  */
668                 return 0;
669
670         if (for_each_remote_ref_submodule(path, has_remote, NULL) > 0) {
671                 struct child_process cp = CHILD_PROCESS_INIT;
672                 struct strbuf buf = STRBUF_INIT;
673                 int needs_pushing = 0;
674
675                 argv_array_push(&cp.args, "rev-list");
676                 oid_array_for_each_unique(commits, append_oid_to_argv, &cp.args);
677                 argv_array_pushl(&cp.args, "--not", "--remotes", "-n", "1" , NULL);
678
679                 prepare_submodule_repo_env(&cp.env_array);
680                 cp.git_cmd = 1;
681                 cp.no_stdin = 1;
682                 cp.out = -1;
683                 cp.dir = path;
684                 if (start_command(&cp))
685                         die("Could not run 'git rev-list <commits> --not --remotes -n 1' command in submodule %s",
686                                         path);
687                 if (strbuf_read(&buf, cp.out, 41))
688                         needs_pushing = 1;
689                 finish_command(&cp);
690                 close(cp.out);
691                 strbuf_release(&buf);
692                 return needs_pushing;
693         }
694
695         return 0;
696 }
697
698 static struct oid_array *submodule_commits(struct string_list *submodules,
699                                             const char *path)
700 {
701         struct string_list_item *item;
702
703         item = string_list_insert(submodules, path);
704         if (item->util)
705                 return (struct oid_array *) item->util;
706
707         /* NEEDSWORK: should we have oid_array_init()? */
708         item->util = xcalloc(1, sizeof(struct oid_array));
709         return (struct oid_array *) item->util;
710 }
711
712 static void collect_submodules_from_diff(struct diff_queue_struct *q,
713                                          struct diff_options *options,
714                                          void *data)
715 {
716         int i;
717         struct string_list *submodules = data;
718
719         for (i = 0; i < q->nr; i++) {
720                 struct diff_filepair *p = q->queue[i];
721                 struct oid_array *commits;
722                 if (!S_ISGITLINK(p->two->mode))
723                         continue;
724                 commits = submodule_commits(submodules, p->two->path);
725                 oid_array_append(commits, &p->two->oid);
726         }
727 }
728
729 static void find_unpushed_submodule_commits(struct commit *commit,
730                 struct string_list *needs_pushing)
731 {
732         struct rev_info rev;
733
734         init_revisions(&rev, NULL);
735         rev.diffopt.output_format |= DIFF_FORMAT_CALLBACK;
736         rev.diffopt.format_callback = collect_submodules_from_diff;
737         rev.diffopt.format_callback_data = needs_pushing;
738         diff_tree_combined_merge(commit, 1, &rev);
739 }
740
741 static void free_submodules_oids(struct string_list *submodules)
742 {
743         struct string_list_item *item;
744         for_each_string_list_item(item, submodules)
745                 oid_array_clear((struct oid_array *) item->util);
746         string_list_clear(submodules, 1);
747 }
748
749 int find_unpushed_submodules(struct oid_array *commits,
750                 const char *remotes_name, struct string_list *needs_pushing)
751 {
752         struct rev_info rev;
753         struct commit *commit;
754         struct string_list submodules = STRING_LIST_INIT_DUP;
755         struct string_list_item *submodule;
756         struct argv_array argv = ARGV_ARRAY_INIT;
757
758         init_revisions(&rev, NULL);
759
760         /* argv.argv[0] will be ignored by setup_revisions */
761         argv_array_push(&argv, "find_unpushed_submodules");
762         oid_array_for_each_unique(commits, append_oid_to_argv, &argv);
763         argv_array_push(&argv, "--not");
764         argv_array_pushf(&argv, "--remotes=%s", remotes_name);
765
766         setup_revisions(argv.argc, argv.argv, &rev, NULL);
767         if (prepare_revision_walk(&rev))
768                 die("revision walk setup failed");
769
770         while ((commit = get_revision(&rev)) != NULL)
771                 find_unpushed_submodule_commits(commit, &submodules);
772
773         reset_revision_walk();
774         argv_array_clear(&argv);
775
776         for_each_string_list_item(submodule, &submodules) {
777                 struct oid_array *commits = (struct oid_array *) submodule->util;
778
779                 if (submodule_needs_pushing(submodule->string, commits))
780                         string_list_insert(needs_pushing, submodule->string);
781         }
782
783         free_submodules_oids(&submodules);
784
785         return needs_pushing->nr;
786 }
787
788 static int push_submodule(const char *path,
789                           const struct remote *remote,
790                           const char **refspec, int refspec_nr,
791                           const struct string_list *push_options,
792                           int dry_run)
793 {
794         if (add_submodule_odb(path))
795                 return 1;
796
797         if (for_each_remote_ref_submodule(path, has_remote, NULL) > 0) {
798                 struct child_process cp = CHILD_PROCESS_INIT;
799                 argv_array_push(&cp.args, "push");
800                 if (dry_run)
801                         argv_array_push(&cp.args, "--dry-run");
802
803                 if (push_options && push_options->nr) {
804                         const struct string_list_item *item;
805                         for_each_string_list_item(item, push_options)
806                                 argv_array_pushf(&cp.args, "--push-option=%s",
807                                                  item->string);
808                 }
809
810                 if (remote->origin != REMOTE_UNCONFIGURED) {
811                         int i;
812                         argv_array_push(&cp.args, remote->name);
813                         for (i = 0; i < refspec_nr; i++)
814                                 argv_array_push(&cp.args, refspec[i]);
815                 }
816
817                 prepare_submodule_repo_env(&cp.env_array);
818                 cp.git_cmd = 1;
819                 cp.no_stdin = 1;
820                 cp.dir = path;
821                 if (run_command(&cp))
822                         return 0;
823                 close(cp.out);
824         }
825
826         return 1;
827 }
828
829 /*
830  * Perform a check in the submodule to see if the remote and refspec work.
831  * Die if the submodule can't be pushed.
832  */
833 static void submodule_push_check(const char *path, const struct remote *remote,
834                                  const char **refspec, int refspec_nr)
835 {
836         struct child_process cp = CHILD_PROCESS_INIT;
837         int i;
838
839         argv_array_push(&cp.args, "submodule--helper");
840         argv_array_push(&cp.args, "push-check");
841         argv_array_push(&cp.args, remote->name);
842
843         for (i = 0; i < refspec_nr; i++)
844                 argv_array_push(&cp.args, refspec[i]);
845
846         prepare_submodule_repo_env(&cp.env_array);
847         cp.git_cmd = 1;
848         cp.no_stdin = 1;
849         cp.no_stdout = 1;
850         cp.dir = path;
851
852         /*
853          * Simply indicate if 'submodule--helper push-check' failed.
854          * More detailed error information will be provided by the
855          * child process.
856          */
857         if (run_command(&cp))
858                 die("process for submodule '%s' failed", path);
859 }
860
861 int push_unpushed_submodules(struct oid_array *commits,
862                              const struct remote *remote,
863                              const char **refspec, int refspec_nr,
864                              const struct string_list *push_options,
865                              int dry_run)
866 {
867         int i, ret = 1;
868         struct string_list needs_pushing = STRING_LIST_INIT_DUP;
869
870         if (!find_unpushed_submodules(commits, remote->name, &needs_pushing))
871                 return 1;
872
873         /*
874          * Verify that the remote and refspec can be propagated to all
875          * submodules.  This check can be skipped if the remote and refspec
876          * won't be propagated due to the remote being unconfigured (e.g. a URL
877          * instead of a remote name).
878          */
879         if (remote->origin != REMOTE_UNCONFIGURED)
880                 for (i = 0; i < needs_pushing.nr; i++)
881                         submodule_push_check(needs_pushing.items[i].string,
882                                              remote, refspec, refspec_nr);
883
884         /* Actually push the submodules */
885         for (i = 0; i < needs_pushing.nr; i++) {
886                 const char *path = needs_pushing.items[i].string;
887                 fprintf(stderr, "Pushing submodule '%s'\n", path);
888                 if (!push_submodule(path, remote, refspec, refspec_nr,
889                                     push_options, dry_run)) {
890                         fprintf(stderr, "Unable to push submodule '%s'\n", path);
891                         ret = 0;
892                 }
893         }
894
895         string_list_clear(&needs_pushing, 0);
896
897         return ret;
898 }
899
900 static int is_submodule_commit_present(const char *path, unsigned char sha1[20])
901 {
902         int is_present = 0;
903         if (!add_submodule_odb(path) && lookup_commit_reference(sha1)) {
904                 /* Even if the submodule is checked out and the commit is
905                  * present, make sure it is reachable from a ref. */
906                 struct child_process cp = CHILD_PROCESS_INIT;
907                 const char *argv[] = {"rev-list", "-n", "1", NULL, "--not", "--all", NULL};
908                 struct strbuf buf = STRBUF_INIT;
909
910                 argv[3] = sha1_to_hex(sha1);
911                 cp.argv = argv;
912                 prepare_submodule_repo_env(&cp.env_array);
913                 cp.git_cmd = 1;
914                 cp.no_stdin = 1;
915                 cp.dir = path;
916                 if (!capture_command(&cp, &buf, 1024) && !buf.len)
917                         is_present = 1;
918
919                 strbuf_release(&buf);
920         }
921         return is_present;
922 }
923
924 static void submodule_collect_changed_cb(struct diff_queue_struct *q,
925                                          struct diff_options *options,
926                                          void *data)
927 {
928         int i;
929         for (i = 0; i < q->nr; i++) {
930                 struct diff_filepair *p = q->queue[i];
931                 if (!S_ISGITLINK(p->two->mode))
932                         continue;
933
934                 if (S_ISGITLINK(p->one->mode)) {
935                         /* NEEDSWORK: We should honor the name configured in
936                          * the .gitmodules file of the commit we are examining
937                          * here to be able to correctly follow submodules
938                          * being moved around. */
939                         struct string_list_item *path;
940                         path = unsorted_string_list_lookup(&changed_submodule_paths, p->two->path);
941                         if (!path && !is_submodule_commit_present(p->two->path, p->two->oid.hash))
942                                 string_list_append(&changed_submodule_paths, xstrdup(p->two->path));
943                 } else {
944                         /* Submodule is new or was moved here */
945                         /* NEEDSWORK: When the .git directories of submodules
946                          * live inside the superprojects .git directory some
947                          * day we should fetch new submodules directly into
948                          * that location too when config or options request
949                          * that so they can be checked out from there. */
950                         continue;
951                 }
952         }
953 }
954
955 static int append_oid_to_array(const char *ref, const struct object_id *oid,
956                                int flags, void *data)
957 {
958         struct oid_array *array = data;
959         oid_array_append(array, oid);
960         return 0;
961 }
962
963 void check_for_new_submodule_commits(struct object_id *oid)
964 {
965         if (!initialized_fetch_ref_tips) {
966                 for_each_ref(append_oid_to_array, &ref_tips_before_fetch);
967                 initialized_fetch_ref_tips = 1;
968         }
969
970         oid_array_append(&ref_tips_after_fetch, oid);
971 }
972
973 static int add_oid_to_argv(const struct object_id *oid, void *data)
974 {
975         argv_array_push(data, oid_to_hex(oid));
976         return 0;
977 }
978
979 static void calculate_changed_submodule_paths(void)
980 {
981         struct rev_info rev;
982         struct commit *commit;
983         struct argv_array argv = ARGV_ARRAY_INIT;
984
985         /* No need to check if there are no submodules configured */
986         if (!submodule_from_path(NULL, NULL))
987                 return;
988
989         init_revisions(&rev, NULL);
990         argv_array_push(&argv, "--"); /* argv[0] program name */
991         oid_array_for_each_unique(&ref_tips_after_fetch,
992                                    add_oid_to_argv, &argv);
993         argv_array_push(&argv, "--not");
994         oid_array_for_each_unique(&ref_tips_before_fetch,
995                                    add_oid_to_argv, &argv);
996         setup_revisions(argv.argc, argv.argv, &rev, NULL);
997         if (prepare_revision_walk(&rev))
998                 die("revision walk setup failed");
999
1000         /*
1001          * Collect all submodules (whether checked out or not) for which new
1002          * commits have been recorded upstream in "changed_submodule_paths".
1003          */
1004         while ((commit = get_revision(&rev))) {
1005                 struct commit_list *parent = commit->parents;
1006                 while (parent) {
1007                         struct diff_options diff_opts;
1008                         diff_setup(&diff_opts);
1009                         DIFF_OPT_SET(&diff_opts, RECURSIVE);
1010                         diff_opts.output_format |= DIFF_FORMAT_CALLBACK;
1011                         diff_opts.format_callback = submodule_collect_changed_cb;
1012                         diff_setup_done(&diff_opts);
1013                         diff_tree_sha1(parent->item->object.oid.hash, commit->object.oid.hash, "", &diff_opts);
1014                         diffcore_std(&diff_opts);
1015                         diff_flush(&diff_opts);
1016                         parent = parent->next;
1017                 }
1018         }
1019
1020         argv_array_clear(&argv);
1021         oid_array_clear(&ref_tips_before_fetch);
1022         oid_array_clear(&ref_tips_after_fetch);
1023         initialized_fetch_ref_tips = 0;
1024 }
1025
1026 struct submodule_parallel_fetch {
1027         int count;
1028         struct argv_array args;
1029         const char *work_tree;
1030         const char *prefix;
1031         int command_line_option;
1032         int quiet;
1033         int result;
1034 };
1035 #define SPF_INIT {0, ARGV_ARRAY_INIT, NULL, NULL, 0, 0, 0}
1036
1037 static int get_next_submodule(struct child_process *cp,
1038                               struct strbuf *err, void *data, void **task_cb)
1039 {
1040         int ret = 0;
1041         struct submodule_parallel_fetch *spf = data;
1042
1043         for (; spf->count < active_nr; spf->count++) {
1044                 struct strbuf submodule_path = STRBUF_INIT;
1045                 struct strbuf submodule_git_dir = STRBUF_INIT;
1046                 struct strbuf submodule_prefix = STRBUF_INIT;
1047                 const struct cache_entry *ce = active_cache[spf->count];
1048                 const char *git_dir, *default_argv;
1049                 const struct submodule *submodule;
1050
1051                 if (!S_ISGITLINK(ce->ce_mode))
1052                         continue;
1053
1054                 submodule = submodule_from_path(null_sha1, ce->name);
1055                 if (!submodule)
1056                         submodule = submodule_from_name(null_sha1, ce->name);
1057
1058                 default_argv = "yes";
1059                 if (spf->command_line_option == RECURSE_SUBMODULES_DEFAULT) {
1060                         if (submodule &&
1061                             submodule->fetch_recurse !=
1062                                                 RECURSE_SUBMODULES_NONE) {
1063                                 if (submodule->fetch_recurse ==
1064                                                 RECURSE_SUBMODULES_OFF)
1065                                         continue;
1066                                 if (submodule->fetch_recurse ==
1067                                                 RECURSE_SUBMODULES_ON_DEMAND) {
1068                                         if (!unsorted_string_list_lookup(&changed_submodule_paths, ce->name))
1069                                                 continue;
1070                                         default_argv = "on-demand";
1071                                 }
1072                         } else {
1073                                 if ((config_fetch_recurse_submodules == RECURSE_SUBMODULES_OFF) ||
1074                                     gitmodules_is_unmerged)
1075                                         continue;
1076                                 if (config_fetch_recurse_submodules == RECURSE_SUBMODULES_ON_DEMAND) {
1077                                         if (!unsorted_string_list_lookup(&changed_submodule_paths, ce->name))
1078                                                 continue;
1079                                         default_argv = "on-demand";
1080                                 }
1081                         }
1082                 } else if (spf->command_line_option == RECURSE_SUBMODULES_ON_DEMAND) {
1083                         if (!unsorted_string_list_lookup(&changed_submodule_paths, ce->name))
1084                                 continue;
1085                         default_argv = "on-demand";
1086                 }
1087
1088                 strbuf_addf(&submodule_path, "%s/%s", spf->work_tree, ce->name);
1089                 strbuf_addf(&submodule_git_dir, "%s/.git", submodule_path.buf);
1090                 strbuf_addf(&submodule_prefix, "%s%s/", spf->prefix, ce->name);
1091                 git_dir = read_gitfile(submodule_git_dir.buf);
1092                 if (!git_dir)
1093                         git_dir = submodule_git_dir.buf;
1094                 if (is_directory(git_dir)) {
1095                         child_process_init(cp);
1096                         cp->dir = strbuf_detach(&submodule_path, NULL);
1097                         prepare_submodule_repo_env(&cp->env_array);
1098                         cp->git_cmd = 1;
1099                         if (!spf->quiet)
1100                                 strbuf_addf(err, "Fetching submodule %s%s\n",
1101                                             spf->prefix, ce->name);
1102                         argv_array_init(&cp->args);
1103                         argv_array_pushv(&cp->args, spf->args.argv);
1104                         argv_array_push(&cp->args, default_argv);
1105                         argv_array_push(&cp->args, "--submodule-prefix");
1106                         argv_array_push(&cp->args, submodule_prefix.buf);
1107                         ret = 1;
1108                 }
1109                 strbuf_release(&submodule_path);
1110                 strbuf_release(&submodule_git_dir);
1111                 strbuf_release(&submodule_prefix);
1112                 if (ret) {
1113                         spf->count++;
1114                         return 1;
1115                 }
1116         }
1117         return 0;
1118 }
1119
1120 static int fetch_start_failure(struct strbuf *err,
1121                                void *cb, void *task_cb)
1122 {
1123         struct submodule_parallel_fetch *spf = cb;
1124
1125         spf->result = 1;
1126
1127         return 0;
1128 }
1129
1130 static int fetch_finish(int retvalue, struct strbuf *err,
1131                         void *cb, void *task_cb)
1132 {
1133         struct submodule_parallel_fetch *spf = cb;
1134
1135         if (retvalue)
1136                 spf->result = 1;
1137
1138         return 0;
1139 }
1140
1141 int fetch_populated_submodules(const struct argv_array *options,
1142                                const char *prefix, int command_line_option,
1143                                int quiet, int max_parallel_jobs)
1144 {
1145         int i;
1146         struct submodule_parallel_fetch spf = SPF_INIT;
1147
1148         spf.work_tree = get_git_work_tree();
1149         spf.command_line_option = command_line_option;
1150         spf.quiet = quiet;
1151         spf.prefix = prefix;
1152
1153         if (!spf.work_tree)
1154                 goto out;
1155
1156         if (read_cache() < 0)
1157                 die("index file corrupt");
1158
1159         argv_array_push(&spf.args, "fetch");
1160         for (i = 0; i < options->argc; i++)
1161                 argv_array_push(&spf.args, options->argv[i]);
1162         argv_array_push(&spf.args, "--recurse-submodules-default");
1163         /* default value, "--submodule-prefix" and its value are added later */
1164
1165         if (max_parallel_jobs < 0)
1166                 max_parallel_jobs = parallel_jobs;
1167
1168         calculate_changed_submodule_paths();
1169         run_processes_parallel(max_parallel_jobs,
1170                                get_next_submodule,
1171                                fetch_start_failure,
1172                                fetch_finish,
1173                                &spf);
1174
1175         argv_array_clear(&spf.args);
1176 out:
1177         string_list_clear(&changed_submodule_paths, 1);
1178         return spf.result;
1179 }
1180
1181 unsigned is_submodule_modified(const char *path, int ignore_untracked)
1182 {
1183         struct child_process cp = CHILD_PROCESS_INIT;
1184         struct strbuf buf = STRBUF_INIT;
1185         FILE *fp;
1186         unsigned dirty_submodule = 0;
1187         const char *git_dir;
1188         int ignore_cp_exit_code = 0;
1189
1190         strbuf_addf(&buf, "%s/.git", path);
1191         git_dir = read_gitfile(buf.buf);
1192         if (!git_dir)
1193                 git_dir = buf.buf;
1194         if (!is_git_directory(git_dir)) {
1195                 if (is_directory(git_dir))
1196                         die(_("'%s' not recognized as a git repository"), git_dir);
1197                 strbuf_release(&buf);
1198                 /* The submodule is not checked out, so it is not modified */
1199                 return 0;
1200         }
1201         strbuf_reset(&buf);
1202
1203         argv_array_pushl(&cp.args, "status", "--porcelain=2", NULL);
1204         if (ignore_untracked)
1205                 argv_array_push(&cp.args, "-uno");
1206
1207         prepare_submodule_repo_env(&cp.env_array);
1208         cp.git_cmd = 1;
1209         cp.no_stdin = 1;
1210         cp.out = -1;
1211         cp.dir = path;
1212         if (start_command(&cp))
1213                 die("Could not run 'git status --porcelain=2' in submodule %s", path);
1214
1215         fp = xfdopen(cp.out, "r");
1216         while (strbuf_getwholeline(&buf, fp, '\n') != EOF) {
1217                 /* regular untracked files */
1218                 if (buf.buf[0] == '?')
1219                         dirty_submodule |= DIRTY_SUBMODULE_UNTRACKED;
1220
1221                 if (buf.buf[0] == 'u' ||
1222                     buf.buf[0] == '1' ||
1223                     buf.buf[0] == '2') {
1224                         /* T = line type, XY = status, SSSS = submodule state */
1225                         if (buf.len < strlen("T XY SSSS"))
1226                                 die("BUG: invalid status --porcelain=2 line %s",
1227                                     buf.buf);
1228
1229                         if (buf.buf[5] == 'S' && buf.buf[8] == 'U')
1230                                 /* nested untracked file */
1231                                 dirty_submodule |= DIRTY_SUBMODULE_UNTRACKED;
1232
1233                         if (buf.buf[0] == 'u' ||
1234                             buf.buf[0] == '2' ||
1235                             memcmp(buf.buf + 5, "S..U", 4))
1236                                 /* other change */
1237                                 dirty_submodule |= DIRTY_SUBMODULE_MODIFIED;
1238                 }
1239
1240                 if ((dirty_submodule & DIRTY_SUBMODULE_MODIFIED) &&
1241                     ((dirty_submodule & DIRTY_SUBMODULE_UNTRACKED) ||
1242                      ignore_untracked)) {
1243                         /*
1244                          * We're not interested in any further information from
1245                          * the child any more, neither output nor its exit code.
1246                          */
1247                         ignore_cp_exit_code = 1;
1248                         break;
1249                 }
1250         }
1251         fclose(fp);
1252
1253         if (finish_command(&cp) && !ignore_cp_exit_code)
1254                 die("'git status --porcelain=2' failed in submodule %s", path);
1255
1256         strbuf_release(&buf);
1257         return dirty_submodule;
1258 }
1259
1260 int submodule_uses_gitfile(const char *path)
1261 {
1262         struct child_process cp = CHILD_PROCESS_INIT;
1263         const char *argv[] = {
1264                 "submodule",
1265                 "foreach",
1266                 "--quiet",
1267                 "--recursive",
1268                 "test -f .git",
1269                 NULL,
1270         };
1271         struct strbuf buf = STRBUF_INIT;
1272         const char *git_dir;
1273
1274         strbuf_addf(&buf, "%s/.git", path);
1275         git_dir = read_gitfile(buf.buf);
1276         if (!git_dir) {
1277                 strbuf_release(&buf);
1278                 return 0;
1279         }
1280         strbuf_release(&buf);
1281
1282         /* Now test that all nested submodules use a gitfile too */
1283         cp.argv = argv;
1284         prepare_submodule_repo_env(&cp.env_array);
1285         cp.git_cmd = 1;
1286         cp.no_stdin = 1;
1287         cp.no_stderr = 1;
1288         cp.no_stdout = 1;
1289         cp.dir = path;
1290         if (run_command(&cp))
1291                 return 0;
1292
1293         return 1;
1294 }
1295
1296 /*
1297  * Check if it is a bad idea to remove a submodule, i.e. if we'd lose data
1298  * when doing so.
1299  *
1300  * Return 1 if we'd lose data, return 0 if the removal is fine,
1301  * and negative values for errors.
1302  */
1303 int bad_to_remove_submodule(const char *path, unsigned flags)
1304 {
1305         ssize_t len;
1306         struct child_process cp = CHILD_PROCESS_INIT;
1307         struct strbuf buf = STRBUF_INIT;
1308         int ret = 0;
1309
1310         if (!file_exists(path) || is_empty_dir(path))
1311                 return 0;
1312
1313         if (!submodule_uses_gitfile(path))
1314                 return 1;
1315
1316         argv_array_pushl(&cp.args, "status", "--porcelain",
1317                                    "--ignore-submodules=none", NULL);
1318
1319         if (flags & SUBMODULE_REMOVAL_IGNORE_UNTRACKED)
1320                 argv_array_push(&cp.args, "-uno");
1321         else
1322                 argv_array_push(&cp.args, "-uall");
1323
1324         if (!(flags & SUBMODULE_REMOVAL_IGNORE_IGNORED_UNTRACKED))
1325                 argv_array_push(&cp.args, "--ignored");
1326
1327         prepare_submodule_repo_env(&cp.env_array);
1328         cp.git_cmd = 1;
1329         cp.no_stdin = 1;
1330         cp.out = -1;
1331         cp.dir = path;
1332         if (start_command(&cp)) {
1333                 if (flags & SUBMODULE_REMOVAL_DIE_ON_ERROR)
1334                         die(_("could not start 'git status' in submodule '%s'"),
1335                                 path);
1336                 ret = -1;
1337                 goto out;
1338         }
1339
1340         len = strbuf_read(&buf, cp.out, 1024);
1341         if (len > 2)
1342                 ret = 1;
1343         close(cp.out);
1344
1345         if (finish_command(&cp)) {
1346                 if (flags & SUBMODULE_REMOVAL_DIE_ON_ERROR)
1347                         die(_("could not run 'git status' in submodule '%s'"),
1348                                 path);
1349                 ret = -1;
1350         }
1351 out:
1352         strbuf_release(&buf);
1353         return ret;
1354 }
1355
1356 static const char *get_super_prefix_or_empty(void)
1357 {
1358         const char *s = get_super_prefix();
1359         if (!s)
1360                 s = "";
1361         return s;
1362 }
1363
1364 static int submodule_has_dirty_index(const struct submodule *sub)
1365 {
1366         struct child_process cp = CHILD_PROCESS_INIT;
1367
1368         prepare_submodule_repo_env_no_git_dir(&cp.env_array);
1369
1370         cp.git_cmd = 1;
1371         argv_array_pushl(&cp.args, "diff-index", "--quiet",
1372                                    "--cached", "HEAD", NULL);
1373         cp.no_stdin = 1;
1374         cp.no_stdout = 1;
1375         cp.dir = sub->path;
1376         if (start_command(&cp))
1377                 die("could not recurse into submodule '%s'", sub->path);
1378
1379         return finish_command(&cp);
1380 }
1381
1382 static void submodule_reset_index(const char *path)
1383 {
1384         struct child_process cp = CHILD_PROCESS_INIT;
1385         prepare_submodule_repo_env_no_git_dir(&cp.env_array);
1386
1387         cp.git_cmd = 1;
1388         cp.no_stdin = 1;
1389         cp.dir = path;
1390
1391         argv_array_pushf(&cp.args, "--super-prefix=%s%s/",
1392                                    get_super_prefix_or_empty(), path);
1393         argv_array_pushl(&cp.args, "read-tree", "-u", "--reset", NULL);
1394
1395         argv_array_push(&cp.args, EMPTY_TREE_SHA1_HEX);
1396
1397         if (run_command(&cp))
1398                 die("could not reset submodule index");
1399 }
1400
1401 /**
1402  * Moves a submodule at a given path from a given head to another new head.
1403  * For edge cases (a submodule coming into existence or removing a submodule)
1404  * pass NULL for old or new respectively.
1405  */
1406 int submodule_move_head(const char *path,
1407                          const char *old,
1408                          const char *new,
1409                          unsigned flags)
1410 {
1411         int ret = 0;
1412         struct child_process cp = CHILD_PROCESS_INIT;
1413         const struct submodule *sub;
1414
1415         sub = submodule_from_path(null_sha1, path);
1416
1417         if (!sub)
1418                 die("BUG: could not get submodule information for '%s'", path);
1419
1420         if (old && !(flags & SUBMODULE_MOVE_HEAD_FORCE)) {
1421                 /* Check if the submodule has a dirty index. */
1422                 if (submodule_has_dirty_index(sub))
1423                         return error(_("submodule '%s' has dirty index"), path);
1424         }
1425
1426         if (!(flags & SUBMODULE_MOVE_HEAD_DRY_RUN)) {
1427                 if (old) {
1428                         if (!submodule_uses_gitfile(path))
1429                                 absorb_git_dir_into_superproject("", path,
1430                                         ABSORB_GITDIR_RECURSE_SUBMODULES);
1431                 } else {
1432                         struct strbuf sb = STRBUF_INIT;
1433                         strbuf_addf(&sb, "%s/modules/%s",
1434                                     get_git_common_dir(), sub->name);
1435                         connect_work_tree_and_git_dir(path, sb.buf);
1436                         strbuf_release(&sb);
1437
1438                         /* make sure the index is clean as well */
1439                         submodule_reset_index(path);
1440                 }
1441         }
1442
1443         prepare_submodule_repo_env_no_git_dir(&cp.env_array);
1444
1445         cp.git_cmd = 1;
1446         cp.no_stdin = 1;
1447         cp.dir = path;
1448
1449         argv_array_pushf(&cp.args, "--super-prefix=%s%s/",
1450                         get_super_prefix_or_empty(), path);
1451         argv_array_pushl(&cp.args, "read-tree", NULL);
1452
1453         if (flags & SUBMODULE_MOVE_HEAD_DRY_RUN)
1454                 argv_array_push(&cp.args, "-n");
1455         else
1456                 argv_array_push(&cp.args, "-u");
1457
1458         if (flags & SUBMODULE_MOVE_HEAD_FORCE)
1459                 argv_array_push(&cp.args, "--reset");
1460         else
1461                 argv_array_push(&cp.args, "-m");
1462
1463         argv_array_push(&cp.args, old ? old : EMPTY_TREE_SHA1_HEX);
1464         argv_array_push(&cp.args, new ? new : EMPTY_TREE_SHA1_HEX);
1465
1466         if (run_command(&cp)) {
1467                 ret = -1;
1468                 goto out;
1469         }
1470
1471         if (!(flags & SUBMODULE_MOVE_HEAD_DRY_RUN)) {
1472                 if (new) {
1473                         struct child_process cp1 = CHILD_PROCESS_INIT;
1474                         /* also set the HEAD accordingly */
1475                         cp1.git_cmd = 1;
1476                         cp1.no_stdin = 1;
1477                         cp1.dir = path;
1478
1479                         argv_array_pushl(&cp1.args, "update-ref", "HEAD", new, NULL);
1480
1481                         if (run_command(&cp1)) {
1482                                 ret = -1;
1483                                 goto out;
1484                         }
1485                 } else {
1486                         struct strbuf sb = STRBUF_INIT;
1487
1488                         strbuf_addf(&sb, "%s/.git", path);
1489                         unlink_or_warn(sb.buf);
1490                         strbuf_release(&sb);
1491
1492                         if (is_empty_dir(path))
1493                                 rmdir_or_warn(path);
1494                 }
1495         }
1496 out:
1497         return ret;
1498 }
1499
1500 static int find_first_merges(struct object_array *result, const char *path,
1501                 struct commit *a, struct commit *b)
1502 {
1503         int i, j;
1504         struct object_array merges = OBJECT_ARRAY_INIT;
1505         struct commit *commit;
1506         int contains_another;
1507
1508         char merged_revision[42];
1509         const char *rev_args[] = { "rev-list", "--merges", "--ancestry-path",
1510                                    "--all", merged_revision, NULL };
1511         struct rev_info revs;
1512         struct setup_revision_opt rev_opts;
1513
1514         memset(result, 0, sizeof(struct object_array));
1515         memset(&rev_opts, 0, sizeof(rev_opts));
1516
1517         /* get all revisions that merge commit a */
1518         xsnprintf(merged_revision, sizeof(merged_revision), "^%s",
1519                         oid_to_hex(&a->object.oid));
1520         init_revisions(&revs, NULL);
1521         rev_opts.submodule = path;
1522         setup_revisions(ARRAY_SIZE(rev_args)-1, rev_args, &revs, &rev_opts);
1523
1524         /* save all revisions from the above list that contain b */
1525         if (prepare_revision_walk(&revs))
1526                 die("revision walk setup failed");
1527         while ((commit = get_revision(&revs)) != NULL) {
1528                 struct object *o = &(commit->object);
1529                 if (in_merge_bases(b, commit))
1530                         add_object_array(o, NULL, &merges);
1531         }
1532         reset_revision_walk();
1533
1534         /* Now we've got all merges that contain a and b. Prune all
1535          * merges that contain another found merge and save them in
1536          * result.
1537          */
1538         for (i = 0; i < merges.nr; i++) {
1539                 struct commit *m1 = (struct commit *) merges.objects[i].item;
1540
1541                 contains_another = 0;
1542                 for (j = 0; j < merges.nr; j++) {
1543                         struct commit *m2 = (struct commit *) merges.objects[j].item;
1544                         if (i != j && in_merge_bases(m2, m1)) {
1545                                 contains_another = 1;
1546                                 break;
1547                         }
1548                 }
1549
1550                 if (!contains_another)
1551                         add_object_array(merges.objects[i].item, NULL, result);
1552         }
1553
1554         free(merges.objects);
1555         return result->nr;
1556 }
1557
1558 static void print_commit(struct commit *commit)
1559 {
1560         struct strbuf sb = STRBUF_INIT;
1561         struct pretty_print_context ctx = {0};
1562         ctx.date_mode.type = DATE_NORMAL;
1563         format_commit_message(commit, " %h: %m %s", &sb, &ctx);
1564         fprintf(stderr, "%s\n", sb.buf);
1565         strbuf_release(&sb);
1566 }
1567
1568 #define MERGE_WARNING(path, msg) \
1569         warning("Failed to merge submodule %s (%s)", path, msg);
1570
1571 int merge_submodule(unsigned char result[20], const char *path,
1572                     const unsigned char base[20], const unsigned char a[20],
1573                     const unsigned char b[20], int search)
1574 {
1575         struct commit *commit_base, *commit_a, *commit_b;
1576         int parent_count;
1577         struct object_array merges;
1578
1579         int i;
1580
1581         /* store a in result in case we fail */
1582         hashcpy(result, a);
1583
1584         /* we can not handle deletion conflicts */
1585         if (is_null_sha1(base))
1586                 return 0;
1587         if (is_null_sha1(a))
1588                 return 0;
1589         if (is_null_sha1(b))
1590                 return 0;
1591
1592         if (add_submodule_odb(path)) {
1593                 MERGE_WARNING(path, "not checked out");
1594                 return 0;
1595         }
1596
1597         if (!(commit_base = lookup_commit_reference(base)) ||
1598             !(commit_a = lookup_commit_reference(a)) ||
1599             !(commit_b = lookup_commit_reference(b))) {
1600                 MERGE_WARNING(path, "commits not present");
1601                 return 0;
1602         }
1603
1604         /* check whether both changes are forward */
1605         if (!in_merge_bases(commit_base, commit_a) ||
1606             !in_merge_bases(commit_base, commit_b)) {
1607                 MERGE_WARNING(path, "commits don't follow merge-base");
1608                 return 0;
1609         }
1610
1611         /* Case #1: a is contained in b or vice versa */
1612         if (in_merge_bases(commit_a, commit_b)) {
1613                 hashcpy(result, b);
1614                 return 1;
1615         }
1616         if (in_merge_bases(commit_b, commit_a)) {
1617                 hashcpy(result, a);
1618                 return 1;
1619         }
1620
1621         /*
1622          * Case #2: There are one or more merges that contain a and b in
1623          * the submodule. If there is only one, then present it as a
1624          * suggestion to the user, but leave it marked unmerged so the
1625          * user needs to confirm the resolution.
1626          */
1627
1628         /* Skip the search if makes no sense to the calling context.  */
1629         if (!search)
1630                 return 0;
1631
1632         /* find commit which merges them */
1633         parent_count = find_first_merges(&merges, path, commit_a, commit_b);
1634         switch (parent_count) {
1635         case 0:
1636                 MERGE_WARNING(path, "merge following commits not found");
1637                 break;
1638
1639         case 1:
1640                 MERGE_WARNING(path, "not fast-forward");
1641                 fprintf(stderr, "Found a possible merge resolution "
1642                                 "for the submodule:\n");
1643                 print_commit((struct commit *) merges.objects[0].item);
1644                 fprintf(stderr,
1645                         "If this is correct simply add it to the index "
1646                         "for example\n"
1647                         "by using:\n\n"
1648                         "  git update-index --cacheinfo 160000 %s \"%s\"\n\n"
1649                         "which will accept this suggestion.\n",
1650                         oid_to_hex(&merges.objects[0].item->oid), path);
1651                 break;
1652
1653         default:
1654                 MERGE_WARNING(path, "multiple merges found");
1655                 for (i = 0; i < merges.nr; i++)
1656                         print_commit((struct commit *) merges.objects[i].item);
1657         }
1658
1659         free(merges.objects);
1660         return 0;
1661 }
1662
1663 int parallel_submodules(void)
1664 {
1665         return parallel_jobs;
1666 }
1667
1668 /*
1669  * Embeds a single submodules git directory into the superprojects git dir,
1670  * non recursively.
1671  */
1672 static void relocate_single_git_dir_into_superproject(const char *prefix,
1673                                                       const char *path)
1674 {
1675         char *old_git_dir = NULL, *real_old_git_dir = NULL, *real_new_git_dir = NULL;
1676         const char *new_git_dir;
1677         const struct submodule *sub;
1678
1679         if (submodule_uses_worktrees(path))
1680                 die(_("relocate_gitdir for submodule '%s' with "
1681                       "more than one worktree not supported"), path);
1682
1683         old_git_dir = xstrfmt("%s/.git", path);
1684         if (read_gitfile(old_git_dir))
1685                 /* If it is an actual gitfile, it doesn't need migration. */
1686                 return;
1687
1688         real_old_git_dir = real_pathdup(old_git_dir, 1);
1689
1690         sub = submodule_from_path(null_sha1, path);
1691         if (!sub)
1692                 die(_("could not lookup name for submodule '%s'"), path);
1693
1694         new_git_dir = git_path("modules/%s", sub->name);
1695         if (safe_create_leading_directories_const(new_git_dir) < 0)
1696                 die(_("could not create directory '%s'"), new_git_dir);
1697         real_new_git_dir = real_pathdup(new_git_dir, 1);
1698
1699         fprintf(stderr, _("Migrating git directory of '%s%s' from\n'%s' to\n'%s'\n"),
1700                 get_super_prefix_or_empty(), path,
1701                 real_old_git_dir, real_new_git_dir);
1702
1703         relocate_gitdir(path, real_old_git_dir, real_new_git_dir);
1704
1705         free(old_git_dir);
1706         free(real_old_git_dir);
1707         free(real_new_git_dir);
1708 }
1709
1710 /*
1711  * Migrate the git directory of the submodule given by path from
1712  * having its git directory within the working tree to the git dir nested
1713  * in its superprojects git dir under modules/.
1714  */
1715 void absorb_git_dir_into_superproject(const char *prefix,
1716                                       const char *path,
1717                                       unsigned flags)
1718 {
1719         int err_code;
1720         const char *sub_git_dir;
1721         struct strbuf gitdir = STRBUF_INIT;
1722         strbuf_addf(&gitdir, "%s/.git", path);
1723         sub_git_dir = resolve_gitdir_gently(gitdir.buf, &err_code);
1724
1725         /* Not populated? */
1726         if (!sub_git_dir) {
1727                 const struct submodule *sub;
1728
1729                 if (err_code == READ_GITFILE_ERR_STAT_FAILED) {
1730                         /* unpopulated as expected */
1731                         strbuf_release(&gitdir);
1732                         return;
1733                 }
1734
1735                 if (err_code != READ_GITFILE_ERR_NOT_A_REPO)
1736                         /* We don't know what broke here. */
1737                         read_gitfile_error_die(err_code, path, NULL);
1738
1739                 /*
1740                 * Maybe populated, but no git directory was found?
1741                 * This can happen if the superproject is a submodule
1742                 * itself and was just absorbed. The absorption of the
1743                 * superproject did not rewrite the git file links yet,
1744                 * fix it now.
1745                 */
1746                 sub = submodule_from_path(null_sha1, path);
1747                 if (!sub)
1748                         die(_("could not lookup name for submodule '%s'"), path);
1749                 connect_work_tree_and_git_dir(path,
1750                         git_path("modules/%s", sub->name));
1751         } else {
1752                 /* Is it already absorbed into the superprojects git dir? */
1753                 char *real_sub_git_dir = real_pathdup(sub_git_dir, 1);
1754                 char *real_common_git_dir = real_pathdup(get_git_common_dir(), 1);
1755
1756                 if (!starts_with(real_sub_git_dir, real_common_git_dir))
1757                         relocate_single_git_dir_into_superproject(prefix, path);
1758
1759                 free(real_sub_git_dir);
1760                 free(real_common_git_dir);
1761         }
1762         strbuf_release(&gitdir);
1763
1764         if (flags & ABSORB_GITDIR_RECURSE_SUBMODULES) {
1765                 struct child_process cp = CHILD_PROCESS_INIT;
1766                 struct strbuf sb = STRBUF_INIT;
1767
1768                 if (flags & ~ABSORB_GITDIR_RECURSE_SUBMODULES)
1769                         die("BUG: we don't know how to pass the flags down?");
1770
1771                 strbuf_addstr(&sb, get_super_prefix_or_empty());
1772                 strbuf_addstr(&sb, path);
1773                 strbuf_addch(&sb, '/');
1774
1775                 cp.dir = path;
1776                 cp.git_cmd = 1;
1777                 cp.no_stdin = 1;
1778                 argv_array_pushl(&cp.args, "--super-prefix", sb.buf,
1779                                            "submodule--helper",
1780                                            "absorb-git-dirs", NULL);
1781                 prepare_submodule_repo_env(&cp.env_array);
1782                 if (run_command(&cp))
1783                         die(_("could not recurse into submodule '%s'"), path);
1784
1785                 strbuf_release(&sb);
1786         }
1787 }
1788
1789 const char *get_superproject_working_tree(void)
1790 {
1791         struct child_process cp = CHILD_PROCESS_INIT;
1792         struct strbuf sb = STRBUF_INIT;
1793         const char *one_up = real_path_if_valid("../");
1794         const char *cwd = xgetcwd();
1795         const char *ret = NULL;
1796         const char *subpath;
1797         int code;
1798         ssize_t len;
1799
1800         if (!is_inside_work_tree())
1801                 /*
1802                  * FIXME:
1803                  * We might have a superproject, but it is harder
1804                  * to determine.
1805                  */
1806                 return NULL;
1807
1808         if (!one_up)
1809                 return NULL;
1810
1811         subpath = relative_path(cwd, one_up, &sb);
1812
1813         prepare_submodule_repo_env(&cp.env_array);
1814         argv_array_pop(&cp.env_array);
1815
1816         argv_array_pushl(&cp.args, "--literal-pathspecs", "-C", "..",
1817                         "ls-files", "-z", "--stage", "--full-name", "--",
1818                         subpath, NULL);
1819         strbuf_reset(&sb);
1820
1821         cp.no_stdin = 1;
1822         cp.no_stderr = 1;
1823         cp.out = -1;
1824         cp.git_cmd = 1;
1825
1826         if (start_command(&cp))
1827                 die(_("could not start ls-files in .."));
1828
1829         len = strbuf_read(&sb, cp.out, PATH_MAX);
1830         close(cp.out);
1831
1832         if (starts_with(sb.buf, "160000")) {
1833                 int super_sub_len;
1834                 int cwd_len = strlen(cwd);
1835                 char *super_sub, *super_wt;
1836
1837                 /*
1838                  * There is a superproject having this repo as a submodule.
1839                  * The format is <mode> SP <hash> SP <stage> TAB <full name> \0,
1840                  * We're only interested in the name after the tab.
1841                  */
1842                 super_sub = strchr(sb.buf, '\t') + 1;
1843                 super_sub_len = sb.buf + sb.len - super_sub - 1;
1844
1845                 if (super_sub_len > cwd_len ||
1846                     strcmp(&cwd[cwd_len - super_sub_len], super_sub))
1847                         die (_("BUG: returned path string doesn't match cwd?"));
1848
1849                 super_wt = xstrdup(cwd);
1850                 super_wt[cwd_len - super_sub_len] = '\0';
1851
1852                 ret = real_path(super_wt);
1853                 free(super_wt);
1854         }
1855         strbuf_release(&sb);
1856
1857         code = finish_command(&cp);
1858
1859         if (code == 128)
1860                 /* '../' is not a git repository */
1861                 return NULL;
1862         if (code == 0 && len == 0)
1863                 /* There is an unrelated git repository at '../' */
1864                 return NULL;
1865         if (code)
1866                 die(_("ls-tree returned unexpected return code %d"), code);
1867
1868         return ret;
1869 }
1870
1871 int submodule_to_gitdir(struct strbuf *buf, const char *submodule)
1872 {
1873         const struct submodule *sub;
1874         const char *git_dir;
1875         int ret = 0;
1876
1877         strbuf_reset(buf);
1878         strbuf_addstr(buf, submodule);
1879         strbuf_complete(buf, '/');
1880         strbuf_addstr(buf, ".git");
1881
1882         git_dir = read_gitfile(buf->buf);
1883         if (git_dir) {
1884                 strbuf_reset(buf);
1885                 strbuf_addstr(buf, git_dir);
1886         }
1887         if (!is_git_directory(buf->buf)) {
1888                 gitmodules_config();
1889                 sub = submodule_from_path(null_sha1, submodule);
1890                 if (!sub) {
1891                         ret = -1;
1892                         goto cleanup;
1893                 }
1894                 strbuf_reset(buf);
1895                 strbuf_git_path(buf, "%s/%s", "modules", sub->name);
1896         }
1897
1898 cleanup:
1899         return ret;
1900 }