submodule: rename add_sha1_to_array()
[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_sha1s(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         free_submodules_sha1s(&submodules);
783
784         return needs_pushing->nr;
785 }
786
787 static int push_submodule(const char *path,
788                           const struct remote *remote,
789                           const char **refspec, int refspec_nr,
790                           const struct string_list *push_options,
791                           int dry_run)
792 {
793         if (add_submodule_odb(path))
794                 return 1;
795
796         if (for_each_remote_ref_submodule(path, has_remote, NULL) > 0) {
797                 struct child_process cp = CHILD_PROCESS_INIT;
798                 argv_array_push(&cp.args, "push");
799                 if (dry_run)
800                         argv_array_push(&cp.args, "--dry-run");
801
802                 if (push_options && push_options->nr) {
803                         const struct string_list_item *item;
804                         for_each_string_list_item(item, push_options)
805                                 argv_array_pushf(&cp.args, "--push-option=%s",
806                                                  item->string);
807                 }
808
809                 if (remote->origin != REMOTE_UNCONFIGURED) {
810                         int i;
811                         argv_array_push(&cp.args, remote->name);
812                         for (i = 0; i < refspec_nr; i++)
813                                 argv_array_push(&cp.args, refspec[i]);
814                 }
815
816                 prepare_submodule_repo_env(&cp.env_array);
817                 cp.git_cmd = 1;
818                 cp.no_stdin = 1;
819                 cp.dir = path;
820                 if (run_command(&cp))
821                         return 0;
822                 close(cp.out);
823         }
824
825         return 1;
826 }
827
828 /*
829  * Perform a check in the submodule to see if the remote and refspec work.
830  * Die if the submodule can't be pushed.
831  */
832 static void submodule_push_check(const char *path, const struct remote *remote,
833                                  const char **refspec, int refspec_nr)
834 {
835         struct child_process cp = CHILD_PROCESS_INIT;
836         int i;
837
838         argv_array_push(&cp.args, "submodule--helper");
839         argv_array_push(&cp.args, "push-check");
840         argv_array_push(&cp.args, remote->name);
841
842         for (i = 0; i < refspec_nr; i++)
843                 argv_array_push(&cp.args, refspec[i]);
844
845         prepare_submodule_repo_env(&cp.env_array);
846         cp.git_cmd = 1;
847         cp.no_stdin = 1;
848         cp.no_stdout = 1;
849         cp.dir = path;
850
851         /*
852          * Simply indicate if 'submodule--helper push-check' failed.
853          * More detailed error information will be provided by the
854          * child process.
855          */
856         if (run_command(&cp))
857                 die("process for submodule '%s' failed", path);
858 }
859
860 int push_unpushed_submodules(struct oid_array *commits,
861                              const struct remote *remote,
862                              const char **refspec, int refspec_nr,
863                              const struct string_list *push_options,
864                              int dry_run)
865 {
866         int i, ret = 1;
867         struct string_list needs_pushing = STRING_LIST_INIT_DUP;
868
869         if (!find_unpushed_submodules(commits, remote->name, &needs_pushing))
870                 return 1;
871
872         /*
873          * Verify that the remote and refspec can be propagated to all
874          * submodules.  This check can be skipped if the remote and refspec
875          * won't be propagated due to the remote being unconfigured (e.g. a URL
876          * instead of a remote name).
877          */
878         if (remote->origin != REMOTE_UNCONFIGURED)
879                 for (i = 0; i < needs_pushing.nr; i++)
880                         submodule_push_check(needs_pushing.items[i].string,
881                                              remote, refspec, refspec_nr);
882
883         /* Actually push the submodules */
884         for (i = 0; i < needs_pushing.nr; i++) {
885                 const char *path = needs_pushing.items[i].string;
886                 fprintf(stderr, "Pushing submodule '%s'\n", path);
887                 if (!push_submodule(path, remote, refspec, refspec_nr,
888                                     push_options, dry_run)) {
889                         fprintf(stderr, "Unable to push submodule '%s'\n", path);
890                         ret = 0;
891                 }
892         }
893
894         string_list_clear(&needs_pushing, 0);
895
896         return ret;
897 }
898
899 static int is_submodule_commit_present(const char *path, unsigned char sha1[20])
900 {
901         int is_present = 0;
902         if (!add_submodule_odb(path) && lookup_commit_reference(sha1)) {
903                 /* Even if the submodule is checked out and the commit is
904                  * present, make sure it is reachable from a ref. */
905                 struct child_process cp = CHILD_PROCESS_INIT;
906                 const char *argv[] = {"rev-list", "-n", "1", NULL, "--not", "--all", NULL};
907                 struct strbuf buf = STRBUF_INIT;
908
909                 argv[3] = sha1_to_hex(sha1);
910                 cp.argv = argv;
911                 prepare_submodule_repo_env(&cp.env_array);
912                 cp.git_cmd = 1;
913                 cp.no_stdin = 1;
914                 cp.dir = path;
915                 if (!capture_command(&cp, &buf, 1024) && !buf.len)
916                         is_present = 1;
917
918                 strbuf_release(&buf);
919         }
920         return is_present;
921 }
922
923 static void submodule_collect_changed_cb(struct diff_queue_struct *q,
924                                          struct diff_options *options,
925                                          void *data)
926 {
927         int i;
928         for (i = 0; i < q->nr; i++) {
929                 struct diff_filepair *p = q->queue[i];
930                 if (!S_ISGITLINK(p->two->mode))
931                         continue;
932
933                 if (S_ISGITLINK(p->one->mode)) {
934                         /* NEEDSWORK: We should honor the name configured in
935                          * the .gitmodules file of the commit we are examining
936                          * here to be able to correctly follow submodules
937                          * being moved around. */
938                         struct string_list_item *path;
939                         path = unsorted_string_list_lookup(&changed_submodule_paths, p->two->path);
940                         if (!path && !is_submodule_commit_present(p->two->path, p->two->oid.hash))
941                                 string_list_append(&changed_submodule_paths, xstrdup(p->two->path));
942                 } else {
943                         /* Submodule is new or was moved here */
944                         /* NEEDSWORK: When the .git directories of submodules
945                          * live inside the superprojects .git directory some
946                          * day we should fetch new submodules directly into
947                          * that location too when config or options request
948                          * that so they can be checked out from there. */
949                         continue;
950                 }
951         }
952 }
953
954 static int append_oid_to_array(const char *ref, const struct object_id *oid,
955                                int flags, void *data)
956 {
957         struct oid_array *array = data;
958         oid_array_append(array, oid);
959         return 0;
960 }
961
962 void check_for_new_submodule_commits(struct object_id *oid)
963 {
964         if (!initialized_fetch_ref_tips) {
965                 for_each_ref(append_oid_to_array, &ref_tips_before_fetch);
966                 initialized_fetch_ref_tips = 1;
967         }
968
969         oid_array_append(&ref_tips_after_fetch, oid);
970 }
971
972 static int add_oid_to_argv(const struct object_id *oid, void *data)
973 {
974         argv_array_push(data, oid_to_hex(oid));
975         return 0;
976 }
977
978 static void calculate_changed_submodule_paths(void)
979 {
980         struct rev_info rev;
981         struct commit *commit;
982         struct argv_array argv = ARGV_ARRAY_INIT;
983
984         /* No need to check if there are no submodules configured */
985         if (!submodule_from_path(NULL, NULL))
986                 return;
987
988         init_revisions(&rev, NULL);
989         argv_array_push(&argv, "--"); /* argv[0] program name */
990         oid_array_for_each_unique(&ref_tips_after_fetch,
991                                    add_oid_to_argv, &argv);
992         argv_array_push(&argv, "--not");
993         oid_array_for_each_unique(&ref_tips_before_fetch,
994                                    add_oid_to_argv, &argv);
995         setup_revisions(argv.argc, argv.argv, &rev, NULL);
996         if (prepare_revision_walk(&rev))
997                 die("revision walk setup failed");
998
999         /*
1000          * Collect all submodules (whether checked out or not) for which new
1001          * commits have been recorded upstream in "changed_submodule_paths".
1002          */
1003         while ((commit = get_revision(&rev))) {
1004                 struct commit_list *parent = commit->parents;
1005                 while (parent) {
1006                         struct diff_options diff_opts;
1007                         diff_setup(&diff_opts);
1008                         DIFF_OPT_SET(&diff_opts, RECURSIVE);
1009                         diff_opts.output_format |= DIFF_FORMAT_CALLBACK;
1010                         diff_opts.format_callback = submodule_collect_changed_cb;
1011                         diff_setup_done(&diff_opts);
1012                         diff_tree_sha1(parent->item->object.oid.hash, commit->object.oid.hash, "", &diff_opts);
1013                         diffcore_std(&diff_opts);
1014                         diff_flush(&diff_opts);
1015                         parent = parent->next;
1016                 }
1017         }
1018
1019         argv_array_clear(&argv);
1020         oid_array_clear(&ref_tips_before_fetch);
1021         oid_array_clear(&ref_tips_after_fetch);
1022         initialized_fetch_ref_tips = 0;
1023 }
1024
1025 struct submodule_parallel_fetch {
1026         int count;
1027         struct argv_array args;
1028         const char *work_tree;
1029         const char *prefix;
1030         int command_line_option;
1031         int quiet;
1032         int result;
1033 };
1034 #define SPF_INIT {0, ARGV_ARRAY_INIT, NULL, NULL, 0, 0, 0}
1035
1036 static int get_next_submodule(struct child_process *cp,
1037                               struct strbuf *err, void *data, void **task_cb)
1038 {
1039         int ret = 0;
1040         struct submodule_parallel_fetch *spf = data;
1041
1042         for (; spf->count < active_nr; spf->count++) {
1043                 struct strbuf submodule_path = STRBUF_INIT;
1044                 struct strbuf submodule_git_dir = STRBUF_INIT;
1045                 struct strbuf submodule_prefix = STRBUF_INIT;
1046                 const struct cache_entry *ce = active_cache[spf->count];
1047                 const char *git_dir, *default_argv;
1048                 const struct submodule *submodule;
1049
1050                 if (!S_ISGITLINK(ce->ce_mode))
1051                         continue;
1052
1053                 submodule = submodule_from_path(null_sha1, ce->name);
1054                 if (!submodule)
1055                         submodule = submodule_from_name(null_sha1, ce->name);
1056
1057                 default_argv = "yes";
1058                 if (spf->command_line_option == RECURSE_SUBMODULES_DEFAULT) {
1059                         if (submodule &&
1060                             submodule->fetch_recurse !=
1061                                                 RECURSE_SUBMODULES_NONE) {
1062                                 if (submodule->fetch_recurse ==
1063                                                 RECURSE_SUBMODULES_OFF)
1064                                         continue;
1065                                 if (submodule->fetch_recurse ==
1066                                                 RECURSE_SUBMODULES_ON_DEMAND) {
1067                                         if (!unsorted_string_list_lookup(&changed_submodule_paths, ce->name))
1068                                                 continue;
1069                                         default_argv = "on-demand";
1070                                 }
1071                         } else {
1072                                 if ((config_fetch_recurse_submodules == RECURSE_SUBMODULES_OFF) ||
1073                                     gitmodules_is_unmerged)
1074                                         continue;
1075                                 if (config_fetch_recurse_submodules == RECURSE_SUBMODULES_ON_DEMAND) {
1076                                         if (!unsorted_string_list_lookup(&changed_submodule_paths, ce->name))
1077                                                 continue;
1078                                         default_argv = "on-demand";
1079                                 }
1080                         }
1081                 } else if (spf->command_line_option == RECURSE_SUBMODULES_ON_DEMAND) {
1082                         if (!unsorted_string_list_lookup(&changed_submodule_paths, ce->name))
1083                                 continue;
1084                         default_argv = "on-demand";
1085                 }
1086
1087                 strbuf_addf(&submodule_path, "%s/%s", spf->work_tree, ce->name);
1088                 strbuf_addf(&submodule_git_dir, "%s/.git", submodule_path.buf);
1089                 strbuf_addf(&submodule_prefix, "%s%s/", spf->prefix, ce->name);
1090                 git_dir = read_gitfile(submodule_git_dir.buf);
1091                 if (!git_dir)
1092                         git_dir = submodule_git_dir.buf;
1093                 if (is_directory(git_dir)) {
1094                         child_process_init(cp);
1095                         cp->dir = strbuf_detach(&submodule_path, NULL);
1096                         prepare_submodule_repo_env(&cp->env_array);
1097                         cp->git_cmd = 1;
1098                         if (!spf->quiet)
1099                                 strbuf_addf(err, "Fetching submodule %s%s\n",
1100                                             spf->prefix, ce->name);
1101                         argv_array_init(&cp->args);
1102                         argv_array_pushv(&cp->args, spf->args.argv);
1103                         argv_array_push(&cp->args, default_argv);
1104                         argv_array_push(&cp->args, "--submodule-prefix");
1105                         argv_array_push(&cp->args, submodule_prefix.buf);
1106                         ret = 1;
1107                 }
1108                 strbuf_release(&submodule_path);
1109                 strbuf_release(&submodule_git_dir);
1110                 strbuf_release(&submodule_prefix);
1111                 if (ret) {
1112                         spf->count++;
1113                         return 1;
1114                 }
1115         }
1116         return 0;
1117 }
1118
1119 static int fetch_start_failure(struct strbuf *err,
1120                                void *cb, void *task_cb)
1121 {
1122         struct submodule_parallel_fetch *spf = cb;
1123
1124         spf->result = 1;
1125
1126         return 0;
1127 }
1128
1129 static int fetch_finish(int retvalue, struct strbuf *err,
1130                         void *cb, void *task_cb)
1131 {
1132         struct submodule_parallel_fetch *spf = cb;
1133
1134         if (retvalue)
1135                 spf->result = 1;
1136
1137         return 0;
1138 }
1139
1140 int fetch_populated_submodules(const struct argv_array *options,
1141                                const char *prefix, int command_line_option,
1142                                int quiet, int max_parallel_jobs)
1143 {
1144         int i;
1145         struct submodule_parallel_fetch spf = SPF_INIT;
1146
1147         spf.work_tree = get_git_work_tree();
1148         spf.command_line_option = command_line_option;
1149         spf.quiet = quiet;
1150         spf.prefix = prefix;
1151
1152         if (!spf.work_tree)
1153                 goto out;
1154
1155         if (read_cache() < 0)
1156                 die("index file corrupt");
1157
1158         argv_array_push(&spf.args, "fetch");
1159         for (i = 0; i < options->argc; i++)
1160                 argv_array_push(&spf.args, options->argv[i]);
1161         argv_array_push(&spf.args, "--recurse-submodules-default");
1162         /* default value, "--submodule-prefix" and its value are added later */
1163
1164         if (max_parallel_jobs < 0)
1165                 max_parallel_jobs = parallel_jobs;
1166
1167         calculate_changed_submodule_paths();
1168         run_processes_parallel(max_parallel_jobs,
1169                                get_next_submodule,
1170                                fetch_start_failure,
1171                                fetch_finish,
1172                                &spf);
1173
1174         argv_array_clear(&spf.args);
1175 out:
1176         string_list_clear(&changed_submodule_paths, 1);
1177         return spf.result;
1178 }
1179
1180 unsigned is_submodule_modified(const char *path, int ignore_untracked)
1181 {
1182         struct child_process cp = CHILD_PROCESS_INIT;
1183         struct strbuf buf = STRBUF_INIT;
1184         FILE *fp;
1185         unsigned dirty_submodule = 0;
1186         const char *git_dir;
1187         int ignore_cp_exit_code = 0;
1188
1189         strbuf_addf(&buf, "%s/.git", path);
1190         git_dir = read_gitfile(buf.buf);
1191         if (!git_dir)
1192                 git_dir = buf.buf;
1193         if (!is_git_directory(git_dir)) {
1194                 if (is_directory(git_dir))
1195                         die(_("'%s' not recognized as a git repository"), git_dir);
1196                 strbuf_release(&buf);
1197                 /* The submodule is not checked out, so it is not modified */
1198                 return 0;
1199         }
1200         strbuf_reset(&buf);
1201
1202         argv_array_pushl(&cp.args, "status", "--porcelain=2", NULL);
1203         if (ignore_untracked)
1204                 argv_array_push(&cp.args, "-uno");
1205
1206         prepare_submodule_repo_env(&cp.env_array);
1207         cp.git_cmd = 1;
1208         cp.no_stdin = 1;
1209         cp.out = -1;
1210         cp.dir = path;
1211         if (start_command(&cp))
1212                 die("Could not run 'git status --porcelain=2' in submodule %s", path);
1213
1214         fp = xfdopen(cp.out, "r");
1215         while (strbuf_getwholeline(&buf, fp, '\n') != EOF) {
1216                 /* regular untracked files */
1217                 if (buf.buf[0] == '?')
1218                         dirty_submodule |= DIRTY_SUBMODULE_UNTRACKED;
1219
1220                 if (buf.buf[0] == 'u' ||
1221                     buf.buf[0] == '1' ||
1222                     buf.buf[0] == '2') {
1223                         /* T = line type, XY = status, SSSS = submodule state */
1224                         if (buf.len < strlen("T XY SSSS"))
1225                                 die("BUG: invalid status --porcelain=2 line %s",
1226                                     buf.buf);
1227
1228                         if (buf.buf[5] == 'S' && buf.buf[8] == 'U')
1229                                 /* nested untracked file */
1230                                 dirty_submodule |= DIRTY_SUBMODULE_UNTRACKED;
1231
1232                         if (buf.buf[0] == 'u' ||
1233                             buf.buf[0] == '2' ||
1234                             memcmp(buf.buf + 5, "S..U", 4))
1235                                 /* other change */
1236                                 dirty_submodule |= DIRTY_SUBMODULE_MODIFIED;
1237                 }
1238
1239                 if ((dirty_submodule & DIRTY_SUBMODULE_MODIFIED) &&
1240                     ((dirty_submodule & DIRTY_SUBMODULE_UNTRACKED) ||
1241                      ignore_untracked)) {
1242                         /*
1243                          * We're not interested in any further information from
1244                          * the child any more, neither output nor its exit code.
1245                          */
1246                         ignore_cp_exit_code = 1;
1247                         break;
1248                 }
1249         }
1250         fclose(fp);
1251
1252         if (finish_command(&cp) && !ignore_cp_exit_code)
1253                 die("'git status --porcelain=2' failed in submodule %s", path);
1254
1255         strbuf_release(&buf);
1256         return dirty_submodule;
1257 }
1258
1259 int submodule_uses_gitfile(const char *path)
1260 {
1261         struct child_process cp = CHILD_PROCESS_INIT;
1262         const char *argv[] = {
1263                 "submodule",
1264                 "foreach",
1265                 "--quiet",
1266                 "--recursive",
1267                 "test -f .git",
1268                 NULL,
1269         };
1270         struct strbuf buf = STRBUF_INIT;
1271         const char *git_dir;
1272
1273         strbuf_addf(&buf, "%s/.git", path);
1274         git_dir = read_gitfile(buf.buf);
1275         if (!git_dir) {
1276                 strbuf_release(&buf);
1277                 return 0;
1278         }
1279         strbuf_release(&buf);
1280
1281         /* Now test that all nested submodules use a gitfile too */
1282         cp.argv = argv;
1283         prepare_submodule_repo_env(&cp.env_array);
1284         cp.git_cmd = 1;
1285         cp.no_stdin = 1;
1286         cp.no_stderr = 1;
1287         cp.no_stdout = 1;
1288         cp.dir = path;
1289         if (run_command(&cp))
1290                 return 0;
1291
1292         return 1;
1293 }
1294
1295 /*
1296  * Check if it is a bad idea to remove a submodule, i.e. if we'd lose data
1297  * when doing so.
1298  *
1299  * Return 1 if we'd lose data, return 0 if the removal is fine,
1300  * and negative values for errors.
1301  */
1302 int bad_to_remove_submodule(const char *path, unsigned flags)
1303 {
1304         ssize_t len;
1305         struct child_process cp = CHILD_PROCESS_INIT;
1306         struct strbuf buf = STRBUF_INIT;
1307         int ret = 0;
1308
1309         if (!file_exists(path) || is_empty_dir(path))
1310                 return 0;
1311
1312         if (!submodule_uses_gitfile(path))
1313                 return 1;
1314
1315         argv_array_pushl(&cp.args, "status", "--porcelain",
1316                                    "--ignore-submodules=none", NULL);
1317
1318         if (flags & SUBMODULE_REMOVAL_IGNORE_UNTRACKED)
1319                 argv_array_push(&cp.args, "-uno");
1320         else
1321                 argv_array_push(&cp.args, "-uall");
1322
1323         if (!(flags & SUBMODULE_REMOVAL_IGNORE_IGNORED_UNTRACKED))
1324                 argv_array_push(&cp.args, "--ignored");
1325
1326         prepare_submodule_repo_env(&cp.env_array);
1327         cp.git_cmd = 1;
1328         cp.no_stdin = 1;
1329         cp.out = -1;
1330         cp.dir = path;
1331         if (start_command(&cp)) {
1332                 if (flags & SUBMODULE_REMOVAL_DIE_ON_ERROR)
1333                         die(_("could not start 'git status' in submodule '%s'"),
1334                                 path);
1335                 ret = -1;
1336                 goto out;
1337         }
1338
1339         len = strbuf_read(&buf, cp.out, 1024);
1340         if (len > 2)
1341                 ret = 1;
1342         close(cp.out);
1343
1344         if (finish_command(&cp)) {
1345                 if (flags & SUBMODULE_REMOVAL_DIE_ON_ERROR)
1346                         die(_("could not run 'git status' in submodule '%s'"),
1347                                 path);
1348                 ret = -1;
1349         }
1350 out:
1351         strbuf_release(&buf);
1352         return ret;
1353 }
1354
1355 static const char *get_super_prefix_or_empty(void)
1356 {
1357         const char *s = get_super_prefix();
1358         if (!s)
1359                 s = "";
1360         return s;
1361 }
1362
1363 static int submodule_has_dirty_index(const struct submodule *sub)
1364 {
1365         struct child_process cp = CHILD_PROCESS_INIT;
1366
1367         prepare_submodule_repo_env_no_git_dir(&cp.env_array);
1368
1369         cp.git_cmd = 1;
1370         argv_array_pushl(&cp.args, "diff-index", "--quiet",
1371                                    "--cached", "HEAD", NULL);
1372         cp.no_stdin = 1;
1373         cp.no_stdout = 1;
1374         cp.dir = sub->path;
1375         if (start_command(&cp))
1376                 die("could not recurse into submodule '%s'", sub->path);
1377
1378         return finish_command(&cp);
1379 }
1380
1381 static void submodule_reset_index(const char *path)
1382 {
1383         struct child_process cp = CHILD_PROCESS_INIT;
1384         prepare_submodule_repo_env_no_git_dir(&cp.env_array);
1385
1386         cp.git_cmd = 1;
1387         cp.no_stdin = 1;
1388         cp.dir = path;
1389
1390         argv_array_pushf(&cp.args, "--super-prefix=%s%s/",
1391                                    get_super_prefix_or_empty(), path);
1392         argv_array_pushl(&cp.args, "read-tree", "-u", "--reset", NULL);
1393
1394         argv_array_push(&cp.args, EMPTY_TREE_SHA1_HEX);
1395
1396         if (run_command(&cp))
1397                 die("could not reset submodule index");
1398 }
1399
1400 /**
1401  * Moves a submodule at a given path from a given head to another new head.
1402  * For edge cases (a submodule coming into existence or removing a submodule)
1403  * pass NULL for old or new respectively.
1404  */
1405 int submodule_move_head(const char *path,
1406                          const char *old,
1407                          const char *new,
1408                          unsigned flags)
1409 {
1410         int ret = 0;
1411         struct child_process cp = CHILD_PROCESS_INIT;
1412         const struct submodule *sub;
1413
1414         sub = submodule_from_path(null_sha1, path);
1415
1416         if (!sub)
1417                 die("BUG: could not get submodule information for '%s'", path);
1418
1419         if (old && !(flags & SUBMODULE_MOVE_HEAD_FORCE)) {
1420                 /* Check if the submodule has a dirty index. */
1421                 if (submodule_has_dirty_index(sub))
1422                         return error(_("submodule '%s' has dirty index"), path);
1423         }
1424
1425         if (!(flags & SUBMODULE_MOVE_HEAD_DRY_RUN)) {
1426                 if (old) {
1427                         if (!submodule_uses_gitfile(path))
1428                                 absorb_git_dir_into_superproject("", path,
1429                                         ABSORB_GITDIR_RECURSE_SUBMODULES);
1430                 } else {
1431                         struct strbuf sb = STRBUF_INIT;
1432                         strbuf_addf(&sb, "%s/modules/%s",
1433                                     get_git_common_dir(), sub->name);
1434                         connect_work_tree_and_git_dir(path, sb.buf);
1435                         strbuf_release(&sb);
1436
1437                         /* make sure the index is clean as well */
1438                         submodule_reset_index(path);
1439                 }
1440         }
1441
1442         prepare_submodule_repo_env_no_git_dir(&cp.env_array);
1443
1444         cp.git_cmd = 1;
1445         cp.no_stdin = 1;
1446         cp.dir = path;
1447
1448         argv_array_pushf(&cp.args, "--super-prefix=%s%s/",
1449                         get_super_prefix_or_empty(), path);
1450         argv_array_pushl(&cp.args, "read-tree", NULL);
1451
1452         if (flags & SUBMODULE_MOVE_HEAD_DRY_RUN)
1453                 argv_array_push(&cp.args, "-n");
1454         else
1455                 argv_array_push(&cp.args, "-u");
1456
1457         if (flags & SUBMODULE_MOVE_HEAD_FORCE)
1458                 argv_array_push(&cp.args, "--reset");
1459         else
1460                 argv_array_push(&cp.args, "-m");
1461
1462         argv_array_push(&cp.args, old ? old : EMPTY_TREE_SHA1_HEX);
1463         argv_array_push(&cp.args, new ? new : EMPTY_TREE_SHA1_HEX);
1464
1465         if (run_command(&cp)) {
1466                 ret = -1;
1467                 goto out;
1468         }
1469
1470         if (!(flags & SUBMODULE_MOVE_HEAD_DRY_RUN)) {
1471                 if (new) {
1472                         struct child_process cp1 = CHILD_PROCESS_INIT;
1473                         /* also set the HEAD accordingly */
1474                         cp1.git_cmd = 1;
1475                         cp1.no_stdin = 1;
1476                         cp1.dir = path;
1477
1478                         argv_array_pushl(&cp1.args, "update-ref", "HEAD", new, NULL);
1479
1480                         if (run_command(&cp1)) {
1481                                 ret = -1;
1482                                 goto out;
1483                         }
1484                 } else {
1485                         struct strbuf sb = STRBUF_INIT;
1486
1487                         strbuf_addf(&sb, "%s/.git", path);
1488                         unlink_or_warn(sb.buf);
1489                         strbuf_release(&sb);
1490
1491                         if (is_empty_dir(path))
1492                                 rmdir_or_warn(path);
1493                 }
1494         }
1495 out:
1496         return ret;
1497 }
1498
1499 static int find_first_merges(struct object_array *result, const char *path,
1500                 struct commit *a, struct commit *b)
1501 {
1502         int i, j;
1503         struct object_array merges = OBJECT_ARRAY_INIT;
1504         struct commit *commit;
1505         int contains_another;
1506
1507         char merged_revision[42];
1508         const char *rev_args[] = { "rev-list", "--merges", "--ancestry-path",
1509                                    "--all", merged_revision, NULL };
1510         struct rev_info revs;
1511         struct setup_revision_opt rev_opts;
1512
1513         memset(result, 0, sizeof(struct object_array));
1514         memset(&rev_opts, 0, sizeof(rev_opts));
1515
1516         /* get all revisions that merge commit a */
1517         xsnprintf(merged_revision, sizeof(merged_revision), "^%s",
1518                         oid_to_hex(&a->object.oid));
1519         init_revisions(&revs, NULL);
1520         rev_opts.submodule = path;
1521         setup_revisions(ARRAY_SIZE(rev_args)-1, rev_args, &revs, &rev_opts);
1522
1523         /* save all revisions from the above list that contain b */
1524         if (prepare_revision_walk(&revs))
1525                 die("revision walk setup failed");
1526         while ((commit = get_revision(&revs)) != NULL) {
1527                 struct object *o = &(commit->object);
1528                 if (in_merge_bases(b, commit))
1529                         add_object_array(o, NULL, &merges);
1530         }
1531         reset_revision_walk();
1532
1533         /* Now we've got all merges that contain a and b. Prune all
1534          * merges that contain another found merge and save them in
1535          * result.
1536          */
1537         for (i = 0; i < merges.nr; i++) {
1538                 struct commit *m1 = (struct commit *) merges.objects[i].item;
1539
1540                 contains_another = 0;
1541                 for (j = 0; j < merges.nr; j++) {
1542                         struct commit *m2 = (struct commit *) merges.objects[j].item;
1543                         if (i != j && in_merge_bases(m2, m1)) {
1544                                 contains_another = 1;
1545                                 break;
1546                         }
1547                 }
1548
1549                 if (!contains_another)
1550                         add_object_array(merges.objects[i].item, NULL, result);
1551         }
1552
1553         free(merges.objects);
1554         return result->nr;
1555 }
1556
1557 static void print_commit(struct commit *commit)
1558 {
1559         struct strbuf sb = STRBUF_INIT;
1560         struct pretty_print_context ctx = {0};
1561         ctx.date_mode.type = DATE_NORMAL;
1562         format_commit_message(commit, " %h: %m %s", &sb, &ctx);
1563         fprintf(stderr, "%s\n", sb.buf);
1564         strbuf_release(&sb);
1565 }
1566
1567 #define MERGE_WARNING(path, msg) \
1568         warning("Failed to merge submodule %s (%s)", path, msg);
1569
1570 int merge_submodule(unsigned char result[20], const char *path,
1571                     const unsigned char base[20], const unsigned char a[20],
1572                     const unsigned char b[20], int search)
1573 {
1574         struct commit *commit_base, *commit_a, *commit_b;
1575         int parent_count;
1576         struct object_array merges;
1577
1578         int i;
1579
1580         /* store a in result in case we fail */
1581         hashcpy(result, a);
1582
1583         /* we can not handle deletion conflicts */
1584         if (is_null_sha1(base))
1585                 return 0;
1586         if (is_null_sha1(a))
1587                 return 0;
1588         if (is_null_sha1(b))
1589                 return 0;
1590
1591         if (add_submodule_odb(path)) {
1592                 MERGE_WARNING(path, "not checked out");
1593                 return 0;
1594         }
1595
1596         if (!(commit_base = lookup_commit_reference(base)) ||
1597             !(commit_a = lookup_commit_reference(a)) ||
1598             !(commit_b = lookup_commit_reference(b))) {
1599                 MERGE_WARNING(path, "commits not present");
1600                 return 0;
1601         }
1602
1603         /* check whether both changes are forward */
1604         if (!in_merge_bases(commit_base, commit_a) ||
1605             !in_merge_bases(commit_base, commit_b)) {
1606                 MERGE_WARNING(path, "commits don't follow merge-base");
1607                 return 0;
1608         }
1609
1610         /* Case #1: a is contained in b or vice versa */
1611         if (in_merge_bases(commit_a, commit_b)) {
1612                 hashcpy(result, b);
1613                 return 1;
1614         }
1615         if (in_merge_bases(commit_b, commit_a)) {
1616                 hashcpy(result, a);
1617                 return 1;
1618         }
1619
1620         /*
1621          * Case #2: There are one or more merges that contain a and b in
1622          * the submodule. If there is only one, then present it as a
1623          * suggestion to the user, but leave it marked unmerged so the
1624          * user needs to confirm the resolution.
1625          */
1626
1627         /* Skip the search if makes no sense to the calling context.  */
1628         if (!search)
1629                 return 0;
1630
1631         /* find commit which merges them */
1632         parent_count = find_first_merges(&merges, path, commit_a, commit_b);
1633         switch (parent_count) {
1634         case 0:
1635                 MERGE_WARNING(path, "merge following commits not found");
1636                 break;
1637
1638         case 1:
1639                 MERGE_WARNING(path, "not fast-forward");
1640                 fprintf(stderr, "Found a possible merge resolution "
1641                                 "for the submodule:\n");
1642                 print_commit((struct commit *) merges.objects[0].item);
1643                 fprintf(stderr,
1644                         "If this is correct simply add it to the index "
1645                         "for example\n"
1646                         "by using:\n\n"
1647                         "  git update-index --cacheinfo 160000 %s \"%s\"\n\n"
1648                         "which will accept this suggestion.\n",
1649                         oid_to_hex(&merges.objects[0].item->oid), path);
1650                 break;
1651
1652         default:
1653                 MERGE_WARNING(path, "multiple merges found");
1654                 for (i = 0; i < merges.nr; i++)
1655                         print_commit((struct commit *) merges.objects[i].item);
1656         }
1657
1658         free(merges.objects);
1659         return 0;
1660 }
1661
1662 int parallel_submodules(void)
1663 {
1664         return parallel_jobs;
1665 }
1666
1667 /*
1668  * Embeds a single submodules git directory into the superprojects git dir,
1669  * non recursively.
1670  */
1671 static void relocate_single_git_dir_into_superproject(const char *prefix,
1672                                                       const char *path)
1673 {
1674         char *old_git_dir = NULL, *real_old_git_dir = NULL, *real_new_git_dir = NULL;
1675         const char *new_git_dir;
1676         const struct submodule *sub;
1677
1678         if (submodule_uses_worktrees(path))
1679                 die(_("relocate_gitdir for submodule '%s' with "
1680                       "more than one worktree not supported"), path);
1681
1682         old_git_dir = xstrfmt("%s/.git", path);
1683         if (read_gitfile(old_git_dir))
1684                 /* If it is an actual gitfile, it doesn't need migration. */
1685                 return;
1686
1687         real_old_git_dir = real_pathdup(old_git_dir, 1);
1688
1689         sub = submodule_from_path(null_sha1, path);
1690         if (!sub)
1691                 die(_("could not lookup name for submodule '%s'"), path);
1692
1693         new_git_dir = git_path("modules/%s", sub->name);
1694         if (safe_create_leading_directories_const(new_git_dir) < 0)
1695                 die(_("could not create directory '%s'"), new_git_dir);
1696         real_new_git_dir = real_pathdup(new_git_dir, 1);
1697
1698         fprintf(stderr, _("Migrating git directory of '%s%s' from\n'%s' to\n'%s'\n"),
1699                 get_super_prefix_or_empty(), path,
1700                 real_old_git_dir, real_new_git_dir);
1701
1702         relocate_gitdir(path, real_old_git_dir, real_new_git_dir);
1703
1704         free(old_git_dir);
1705         free(real_old_git_dir);
1706         free(real_new_git_dir);
1707 }
1708
1709 /*
1710  * Migrate the git directory of the submodule given by path from
1711  * having its git directory within the working tree to the git dir nested
1712  * in its superprojects git dir under modules/.
1713  */
1714 void absorb_git_dir_into_superproject(const char *prefix,
1715                                       const char *path,
1716                                       unsigned flags)
1717 {
1718         int err_code;
1719         const char *sub_git_dir;
1720         struct strbuf gitdir = STRBUF_INIT;
1721         strbuf_addf(&gitdir, "%s/.git", path);
1722         sub_git_dir = resolve_gitdir_gently(gitdir.buf, &err_code);
1723
1724         /* Not populated? */
1725         if (!sub_git_dir) {
1726                 const struct submodule *sub;
1727
1728                 if (err_code == READ_GITFILE_ERR_STAT_FAILED) {
1729                         /* unpopulated as expected */
1730                         strbuf_release(&gitdir);
1731                         return;
1732                 }
1733
1734                 if (err_code != READ_GITFILE_ERR_NOT_A_REPO)
1735                         /* We don't know what broke here. */
1736                         read_gitfile_error_die(err_code, path, NULL);
1737
1738                 /*
1739                 * Maybe populated, but no git directory was found?
1740                 * This can happen if the superproject is a submodule
1741                 * itself and was just absorbed. The absorption of the
1742                 * superproject did not rewrite the git file links yet,
1743                 * fix it now.
1744                 */
1745                 sub = submodule_from_path(null_sha1, path);
1746                 if (!sub)
1747                         die(_("could not lookup name for submodule '%s'"), path);
1748                 connect_work_tree_and_git_dir(path,
1749                         git_path("modules/%s", sub->name));
1750         } else {
1751                 /* Is it already absorbed into the superprojects git dir? */
1752                 char *real_sub_git_dir = real_pathdup(sub_git_dir, 1);
1753                 char *real_common_git_dir = real_pathdup(get_git_common_dir(), 1);
1754
1755                 if (!starts_with(real_sub_git_dir, real_common_git_dir))
1756                         relocate_single_git_dir_into_superproject(prefix, path);
1757
1758                 free(real_sub_git_dir);
1759                 free(real_common_git_dir);
1760         }
1761         strbuf_release(&gitdir);
1762
1763         if (flags & ABSORB_GITDIR_RECURSE_SUBMODULES) {
1764                 struct child_process cp = CHILD_PROCESS_INIT;
1765                 struct strbuf sb = STRBUF_INIT;
1766
1767                 if (flags & ~ABSORB_GITDIR_RECURSE_SUBMODULES)
1768                         die("BUG: we don't know how to pass the flags down?");
1769
1770                 strbuf_addstr(&sb, get_super_prefix_or_empty());
1771                 strbuf_addstr(&sb, path);
1772                 strbuf_addch(&sb, '/');
1773
1774                 cp.dir = path;
1775                 cp.git_cmd = 1;
1776                 cp.no_stdin = 1;
1777                 argv_array_pushl(&cp.args, "--super-prefix", sb.buf,
1778                                            "submodule--helper",
1779                                            "absorb-git-dirs", NULL);
1780                 prepare_submodule_repo_env(&cp.env_array);
1781                 if (run_command(&cp))
1782                         die(_("could not recurse into submodule '%s'"), path);
1783
1784                 strbuf_release(&sb);
1785         }
1786 }
1787
1788 const char *get_superproject_working_tree(void)
1789 {
1790         struct child_process cp = CHILD_PROCESS_INIT;
1791         struct strbuf sb = STRBUF_INIT;
1792         const char *one_up = real_path_if_valid("../");
1793         const char *cwd = xgetcwd();
1794         const char *ret = NULL;
1795         const char *subpath;
1796         int code;
1797         ssize_t len;
1798
1799         if (!is_inside_work_tree())
1800                 /*
1801                  * FIXME:
1802                  * We might have a superproject, but it is harder
1803                  * to determine.
1804                  */
1805                 return NULL;
1806
1807         if (!one_up)
1808                 return NULL;
1809
1810         subpath = relative_path(cwd, one_up, &sb);
1811
1812         prepare_submodule_repo_env(&cp.env_array);
1813         argv_array_pop(&cp.env_array);
1814
1815         argv_array_pushl(&cp.args, "--literal-pathspecs", "-C", "..",
1816                         "ls-files", "-z", "--stage", "--full-name", "--",
1817                         subpath, NULL);
1818         strbuf_reset(&sb);
1819
1820         cp.no_stdin = 1;
1821         cp.no_stderr = 1;
1822         cp.out = -1;
1823         cp.git_cmd = 1;
1824
1825         if (start_command(&cp))
1826                 die(_("could not start ls-files in .."));
1827
1828         len = strbuf_read(&sb, cp.out, PATH_MAX);
1829         close(cp.out);
1830
1831         if (starts_with(sb.buf, "160000")) {
1832                 int super_sub_len;
1833                 int cwd_len = strlen(cwd);
1834                 char *super_sub, *super_wt;
1835
1836                 /*
1837                  * There is a superproject having this repo as a submodule.
1838                  * The format is <mode> SP <hash> SP <stage> TAB <full name> \0,
1839                  * We're only interested in the name after the tab.
1840                  */
1841                 super_sub = strchr(sb.buf, '\t') + 1;
1842                 super_sub_len = sb.buf + sb.len - super_sub - 1;
1843
1844                 if (super_sub_len > cwd_len ||
1845                     strcmp(&cwd[cwd_len - super_sub_len], super_sub))
1846                         die (_("BUG: returned path string doesn't match cwd?"));
1847
1848                 super_wt = xstrdup(cwd);
1849                 super_wt[cwd_len - super_sub_len] = '\0';
1850
1851                 ret = real_path(super_wt);
1852                 free(super_wt);
1853         }
1854         strbuf_release(&sb);
1855
1856         code = finish_command(&cp);
1857
1858         if (code == 128)
1859                 /* '../' is not a git repository */
1860                 return NULL;
1861         if (code == 0 && len == 0)
1862                 /* There is an unrelated git repository at '../' */
1863                 return NULL;
1864         if (code)
1865                 die(_("ls-tree returned unexpected return code %d"), code);
1866
1867         return ret;
1868 }
1869
1870 int submodule_to_gitdir(struct strbuf *buf, const char *submodule)
1871 {
1872         const struct submodule *sub;
1873         const char *git_dir;
1874         int ret = 0;
1875
1876         strbuf_reset(buf);
1877         strbuf_addstr(buf, submodule);
1878         strbuf_complete(buf, '/');
1879         strbuf_addstr(buf, ".git");
1880
1881         git_dir = read_gitfile(buf->buf);
1882         if (git_dir) {
1883                 strbuf_reset(buf);
1884                 strbuf_addstr(buf, git_dir);
1885         }
1886         if (!is_git_directory(buf->buf)) {
1887                 gitmodules_config();
1888                 sub = submodule_from_path(null_sha1, submodule);
1889                 if (!sub) {
1890                         ret = -1;
1891                         goto cleanup;
1892                 }
1893                 strbuf_reset(buf);
1894                 strbuf_git_path(buf, "%s/%s", "modules", sub->name);
1895         }
1896
1897 cleanup:
1898         return ret;
1899 }