remote doc: document long forms of set-head options
[git] / submodule.c
1 #include "cache.h"
2 #include "submodule.h"
3 #include "dir.h"
4 #include "diff.h"
5 #include "commit.h"
6 #include "revision.h"
7 #include "run-command.h"
8 #include "diffcore.h"
9 #include "refs.h"
10 #include "string-list.h"
11 #include "sha1-array.h"
12 #include "argv-array.h"
13
14 static struct string_list config_name_for_path;
15 static struct string_list config_fetch_recurse_submodules_for_name;
16 static struct string_list config_ignore_for_name;
17 static int config_fetch_recurse_submodules = RECURSE_SUBMODULES_ON_DEMAND;
18 static struct string_list changed_submodule_paths;
19 static int initialized_fetch_ref_tips;
20 static struct sha1_array ref_tips_before_fetch;
21 static struct sha1_array ref_tips_after_fetch;
22
23 /*
24  * The following flag is set if the .gitmodules file is unmerged. We then
25  * disable recursion for all submodules where .git/config doesn't have a
26  * matching config entry because we can't guess what might be configured in
27  * .gitmodules unless the user resolves the conflict. When a command line
28  * option is given (which always overrides configuration) this flag will be
29  * ignored.
30  */
31 static int gitmodules_is_unmerged;
32
33 static int add_submodule_odb(const char *path)
34 {
35         struct strbuf objects_directory = STRBUF_INIT;
36         struct alternate_object_database *alt_odb;
37         int ret = 0;
38         const char *git_dir;
39
40         strbuf_addf(&objects_directory, "%s/.git", path);
41         git_dir = read_gitfile(objects_directory.buf);
42         if (git_dir) {
43                 strbuf_reset(&objects_directory);
44                 strbuf_addstr(&objects_directory, git_dir);
45         }
46         strbuf_addstr(&objects_directory, "/objects/");
47         if (!is_directory(objects_directory.buf)) {
48                 ret = -1;
49                 goto done;
50         }
51         /* avoid adding it twice */
52         for (alt_odb = alt_odb_list; alt_odb; alt_odb = alt_odb->next)
53                 if (alt_odb->name - alt_odb->base == objects_directory.len &&
54                                 !strncmp(alt_odb->base, objects_directory.buf,
55                                         objects_directory.len))
56                         goto done;
57
58         alt_odb = xmalloc(objects_directory.len + 42 + sizeof(*alt_odb));
59         alt_odb->next = alt_odb_list;
60         strcpy(alt_odb->base, objects_directory.buf);
61         alt_odb->name = alt_odb->base + objects_directory.len;
62         alt_odb->name[2] = '/';
63         alt_odb->name[40] = '\0';
64         alt_odb->name[41] = '\0';
65         alt_odb_list = alt_odb;
66
67         /* add possible alternates from the submodule */
68         read_info_alternates(objects_directory.buf, 0);
69         prepare_alt_odb();
70 done:
71         strbuf_release(&objects_directory);
72         return ret;
73 }
74
75 void set_diffopt_flags_from_submodule_config(struct diff_options *diffopt,
76                                              const char *path)
77 {
78         struct string_list_item *path_option, *ignore_option;
79         path_option = unsorted_string_list_lookup(&config_name_for_path, path);
80         if (path_option) {
81                 ignore_option = unsorted_string_list_lookup(&config_ignore_for_name, path_option->util);
82                 if (ignore_option)
83                         handle_ignore_submodules_arg(diffopt, ignore_option->util);
84                 else if (gitmodules_is_unmerged)
85                         DIFF_OPT_SET(diffopt, IGNORE_SUBMODULES);
86         }
87 }
88
89 int submodule_config(const char *var, const char *value, void *cb)
90 {
91         if (!prefixcmp(var, "submodule."))
92                 return parse_submodule_config_option(var, value);
93         else if (!strcmp(var, "fetch.recursesubmodules")) {
94                 config_fetch_recurse_submodules = parse_fetch_recurse_submodules_arg(var, value);
95                 return 0;
96         }
97         return 0;
98 }
99
100 void gitmodules_config(void)
101 {
102         const char *work_tree = get_git_work_tree();
103         if (work_tree) {
104                 struct strbuf gitmodules_path = STRBUF_INIT;
105                 int pos;
106                 strbuf_addstr(&gitmodules_path, work_tree);
107                 strbuf_addstr(&gitmodules_path, "/.gitmodules");
108                 if (read_cache() < 0)
109                         die("index file corrupt");
110                 pos = cache_name_pos(".gitmodules", 11);
111                 if (pos < 0) { /* .gitmodules not found or isn't merged */
112                         pos = -1 - pos;
113                         if (active_nr > pos) {  /* there is a .gitmodules */
114                                 const struct cache_entry *ce = active_cache[pos];
115                                 if (ce_namelen(ce) == 11 &&
116                                     !memcmp(ce->name, ".gitmodules", 11))
117                                         gitmodules_is_unmerged = 1;
118                         }
119                 }
120
121                 if (!gitmodules_is_unmerged)
122                         git_config_from_file(submodule_config, gitmodules_path.buf, NULL);
123                 strbuf_release(&gitmodules_path);
124         }
125 }
126
127 int parse_submodule_config_option(const char *var, const char *value)
128 {
129         struct string_list_item *config;
130         const char *name, *key;
131         int namelen;
132
133         if (parse_config_key(var, "submodule", &name, &namelen, &key) < 0 || !name)
134                 return 0;
135
136         if (!strcmp(key, "path")) {
137                 if (!value)
138                         return config_error_nonbool(var);
139
140                 config = unsorted_string_list_lookup(&config_name_for_path, value);
141                 if (config)
142                         free(config->util);
143                 else
144                         config = string_list_append(&config_name_for_path, xstrdup(value));
145                 config->util = xmemdupz(name, namelen);
146         } else if (!strcmp(key, "fetchrecursesubmodules")) {
147                 char *name_cstr = xmemdupz(name, namelen);
148                 config = unsorted_string_list_lookup(&config_fetch_recurse_submodules_for_name, name_cstr);
149                 if (!config)
150                         config = string_list_append(&config_fetch_recurse_submodules_for_name, name_cstr);
151                 else
152                         free(name_cstr);
153                 config->util = (void *)(intptr_t)parse_fetch_recurse_submodules_arg(var, value);
154         } else if (!strcmp(key, "ignore")) {
155                 char *name_cstr;
156
157                 if (!value)
158                         return config_error_nonbool(var);
159
160                 if (strcmp(value, "untracked") && strcmp(value, "dirty") &&
161                     strcmp(value, "all") && strcmp(value, "none")) {
162                         warning("Invalid parameter \"%s\" for config option \"submodule.%s.ignore\"", value, var);
163                         return 0;
164                 }
165
166                 name_cstr = xmemdupz(name, namelen);
167                 config = unsorted_string_list_lookup(&config_ignore_for_name, name_cstr);
168                 if (config) {
169                         free(config->util);
170                         free(name_cstr);
171                 } else
172                         config = string_list_append(&config_ignore_for_name, name_cstr);
173                 config->util = xstrdup(value);
174                 return 0;
175         }
176         return 0;
177 }
178
179 void handle_ignore_submodules_arg(struct diff_options *diffopt,
180                                   const char *arg)
181 {
182         DIFF_OPT_CLR(diffopt, IGNORE_SUBMODULES);
183         DIFF_OPT_CLR(diffopt, IGNORE_UNTRACKED_IN_SUBMODULES);
184         DIFF_OPT_CLR(diffopt, IGNORE_DIRTY_SUBMODULES);
185
186         if (!strcmp(arg, "all"))
187                 DIFF_OPT_SET(diffopt, IGNORE_SUBMODULES);
188         else if (!strcmp(arg, "untracked"))
189                 DIFF_OPT_SET(diffopt, IGNORE_UNTRACKED_IN_SUBMODULES);
190         else if (!strcmp(arg, "dirty"))
191                 DIFF_OPT_SET(diffopt, IGNORE_DIRTY_SUBMODULES);
192         else if (strcmp(arg, "none"))
193                 die("bad --ignore-submodules argument: %s", arg);
194 }
195
196 static int prepare_submodule_summary(struct rev_info *rev, const char *path,
197                 struct commit *left, struct commit *right,
198                 int *fast_forward, int *fast_backward)
199 {
200         struct commit_list *merge_bases, *list;
201
202         init_revisions(rev, NULL);
203         setup_revisions(0, NULL, rev, NULL);
204         rev->left_right = 1;
205         rev->first_parent_only = 1;
206         left->object.flags |= SYMMETRIC_LEFT;
207         add_pending_object(rev, &left->object, path);
208         add_pending_object(rev, &right->object, path);
209         merge_bases = get_merge_bases(left, right, 1);
210         if (merge_bases) {
211                 if (merge_bases->item == left)
212                         *fast_forward = 1;
213                 else if (merge_bases->item == right)
214                         *fast_backward = 1;
215         }
216         for (list = merge_bases; list; list = list->next) {
217                 list->item->object.flags |= UNINTERESTING;
218                 add_pending_object(rev, &list->item->object,
219                         sha1_to_hex(list->item->object.sha1));
220         }
221         return prepare_revision_walk(rev);
222 }
223
224 static void print_submodule_summary(struct rev_info *rev, FILE *f,
225                 const char *line_prefix,
226                 const char *del, const char *add, const char *reset)
227 {
228         static const char format[] = "  %m %s";
229         struct strbuf sb = STRBUF_INIT;
230         struct commit *commit;
231
232         while ((commit = get_revision(rev))) {
233                 struct pretty_print_context ctx = {0};
234                 ctx.date_mode = rev->date_mode;
235                 ctx.output_encoding = get_log_output_encoding();
236                 strbuf_setlen(&sb, 0);
237                 strbuf_addstr(&sb, line_prefix);
238                 if (commit->object.flags & SYMMETRIC_LEFT) {
239                         if (del)
240                                 strbuf_addstr(&sb, del);
241                 }
242                 else if (add)
243                         strbuf_addstr(&sb, add);
244                 format_commit_message(commit, format, &sb, &ctx);
245                 if (reset)
246                         strbuf_addstr(&sb, reset);
247                 strbuf_addch(&sb, '\n');
248                 fprintf(f, "%s", sb.buf);
249         }
250         strbuf_release(&sb);
251 }
252
253 int parse_fetch_recurse_submodules_arg(const char *opt, const char *arg)
254 {
255         switch (git_config_maybe_bool(opt, arg)) {
256         case 1:
257                 return RECURSE_SUBMODULES_ON;
258         case 0:
259                 return RECURSE_SUBMODULES_OFF;
260         default:
261                 if (!strcmp(arg, "on-demand"))
262                         return RECURSE_SUBMODULES_ON_DEMAND;
263                 die("bad %s argument: %s", opt, arg);
264         }
265 }
266
267 void show_submodule_summary(FILE *f, const char *path,
268                 const char *line_prefix,
269                 unsigned char one[20], unsigned char two[20],
270                 unsigned dirty_submodule, const char *meta,
271                 const char *del, const char *add, const char *reset)
272 {
273         struct rev_info rev;
274         struct commit *left = NULL, *right = NULL;
275         const char *message = NULL;
276         struct strbuf sb = STRBUF_INIT;
277         int fast_forward = 0, fast_backward = 0;
278
279         if (is_null_sha1(two))
280                 message = "(submodule deleted)";
281         else if (add_submodule_odb(path))
282                 message = "(not checked out)";
283         else if (is_null_sha1(one))
284                 message = "(new submodule)";
285         else if (!(left = lookup_commit_reference(one)) ||
286                  !(right = lookup_commit_reference(two)))
287                 message = "(commits not present)";
288         else if (prepare_submodule_summary(&rev, path, left, right,
289                                            &fast_forward, &fast_backward))
290                 message = "(revision walker failed)";
291
292         if (dirty_submodule & DIRTY_SUBMODULE_UNTRACKED)
293                 fprintf(f, "%sSubmodule %s contains untracked content\n",
294                         line_prefix, path);
295         if (dirty_submodule & DIRTY_SUBMODULE_MODIFIED)
296                 fprintf(f, "%sSubmodule %s contains modified content\n",
297                         line_prefix, path);
298
299         if (!hashcmp(one, two)) {
300                 strbuf_release(&sb);
301                 return;
302         }
303
304         strbuf_addf(&sb, "%s%sSubmodule %s %s..", line_prefix, meta, path,
305                         find_unique_abbrev(one, DEFAULT_ABBREV));
306         if (!fast_backward && !fast_forward)
307                 strbuf_addch(&sb, '.');
308         strbuf_addf(&sb, "%s", find_unique_abbrev(two, DEFAULT_ABBREV));
309         if (message)
310                 strbuf_addf(&sb, " %s%s\n", message, reset);
311         else
312                 strbuf_addf(&sb, "%s:%s\n", fast_backward ? " (rewind)" : "", reset);
313         fwrite(sb.buf, sb.len, 1, f);
314
315         if (!message) /* only NULL if we succeeded in setting up the walk */
316                 print_submodule_summary(&rev, f, line_prefix, del, add, reset);
317         if (left)
318                 clear_commit_marks(left, ~0);
319         if (right)
320                 clear_commit_marks(right, ~0);
321
322         strbuf_release(&sb);
323 }
324
325 void set_config_fetch_recurse_submodules(int value)
326 {
327         config_fetch_recurse_submodules = value;
328 }
329
330 static int has_remote(const char *refname, const unsigned char *sha1, int flags, void *cb_data)
331 {
332         return 1;
333 }
334
335 static int submodule_needs_pushing(const char *path, const unsigned char sha1[20])
336 {
337         if (add_submodule_odb(path) || !lookup_commit_reference(sha1))
338                 return 0;
339
340         if (for_each_remote_ref_submodule(path, has_remote, NULL) > 0) {
341                 struct child_process cp;
342                 const char *argv[] = {"rev-list", NULL, "--not", "--remotes", "-n", "1" , NULL};
343                 struct strbuf buf = STRBUF_INIT;
344                 int needs_pushing = 0;
345
346                 argv[1] = sha1_to_hex(sha1);
347                 memset(&cp, 0, sizeof(cp));
348                 cp.argv = argv;
349                 cp.env = local_repo_env;
350                 cp.git_cmd = 1;
351                 cp.no_stdin = 1;
352                 cp.out = -1;
353                 cp.dir = path;
354                 if (start_command(&cp))
355                         die("Could not run 'git rev-list %s --not --remotes -n 1' command in submodule %s",
356                                 sha1_to_hex(sha1), path);
357                 if (strbuf_read(&buf, cp.out, 41))
358                         needs_pushing = 1;
359                 finish_command(&cp);
360                 close(cp.out);
361                 strbuf_release(&buf);
362                 return needs_pushing;
363         }
364
365         return 0;
366 }
367
368 static void collect_submodules_from_diff(struct diff_queue_struct *q,
369                                          struct diff_options *options,
370                                          void *data)
371 {
372         int i;
373         struct string_list *needs_pushing = data;
374
375         for (i = 0; i < q->nr; i++) {
376                 struct diff_filepair *p = q->queue[i];
377                 if (!S_ISGITLINK(p->two->mode))
378                         continue;
379                 if (submodule_needs_pushing(p->two->path, p->two->sha1))
380                         string_list_insert(needs_pushing, p->two->path);
381         }
382 }
383
384 static void find_unpushed_submodule_commits(struct commit *commit,
385                 struct string_list *needs_pushing)
386 {
387         struct rev_info rev;
388
389         init_revisions(&rev, NULL);
390         rev.diffopt.output_format |= DIFF_FORMAT_CALLBACK;
391         rev.diffopt.format_callback = collect_submodules_from_diff;
392         rev.diffopt.format_callback_data = needs_pushing;
393         diff_tree_combined_merge(commit, 1, &rev);
394 }
395
396 int find_unpushed_submodules(unsigned char new_sha1[20],
397                 const char *remotes_name, struct string_list *needs_pushing)
398 {
399         struct rev_info rev;
400         struct commit *commit;
401         const char *argv[] = {NULL, NULL, "--not", "NULL", NULL};
402         int argc = ARRAY_SIZE(argv) - 1;
403         char *sha1_copy;
404
405         struct strbuf remotes_arg = STRBUF_INIT;
406
407         strbuf_addf(&remotes_arg, "--remotes=%s", remotes_name);
408         init_revisions(&rev, NULL);
409         sha1_copy = xstrdup(sha1_to_hex(new_sha1));
410         argv[1] = sha1_copy;
411         argv[3] = remotes_arg.buf;
412         setup_revisions(argc, argv, &rev, NULL);
413         if (prepare_revision_walk(&rev))
414                 die("revision walk setup failed");
415
416         while ((commit = get_revision(&rev)) != NULL)
417                 find_unpushed_submodule_commits(commit, needs_pushing);
418
419         reset_revision_walk();
420         free(sha1_copy);
421         strbuf_release(&remotes_arg);
422
423         return needs_pushing->nr;
424 }
425
426 static int push_submodule(const char *path)
427 {
428         if (add_submodule_odb(path))
429                 return 1;
430
431         if (for_each_remote_ref_submodule(path, has_remote, NULL) > 0) {
432                 struct child_process cp;
433                 const char *argv[] = {"push", NULL};
434
435                 memset(&cp, 0, sizeof(cp));
436                 cp.argv = argv;
437                 cp.env = local_repo_env;
438                 cp.git_cmd = 1;
439                 cp.no_stdin = 1;
440                 cp.dir = path;
441                 if (run_command(&cp))
442                         return 0;
443                 close(cp.out);
444         }
445
446         return 1;
447 }
448
449 int push_unpushed_submodules(unsigned char new_sha1[20], const char *remotes_name)
450 {
451         int i, ret = 1;
452         struct string_list needs_pushing;
453
454         memset(&needs_pushing, 0, sizeof(struct string_list));
455         needs_pushing.strdup_strings = 1;
456
457         if (!find_unpushed_submodules(new_sha1, remotes_name, &needs_pushing))
458                 return 1;
459
460         for (i = 0; i < needs_pushing.nr; i++) {
461                 const char *path = needs_pushing.items[i].string;
462                 fprintf(stderr, "Pushing submodule '%s'\n", path);
463                 if (!push_submodule(path)) {
464                         fprintf(stderr, "Unable to push submodule '%s'\n", path);
465                         ret = 0;
466                 }
467         }
468
469         string_list_clear(&needs_pushing, 0);
470
471         return ret;
472 }
473
474 static int is_submodule_commit_present(const char *path, unsigned char sha1[20])
475 {
476         int is_present = 0;
477         if (!add_submodule_odb(path) && lookup_commit_reference(sha1)) {
478                 /* Even if the submodule is checked out and the commit is
479                  * present, make sure it is reachable from a ref. */
480                 struct child_process cp;
481                 const char *argv[] = {"rev-list", "-n", "1", NULL, "--not", "--all", NULL};
482                 struct strbuf buf = STRBUF_INIT;
483
484                 argv[3] = sha1_to_hex(sha1);
485                 memset(&cp, 0, sizeof(cp));
486                 cp.argv = argv;
487                 cp.env = local_repo_env;
488                 cp.git_cmd = 1;
489                 cp.no_stdin = 1;
490                 cp.out = -1;
491                 cp.dir = path;
492                 if (!run_command(&cp) && !strbuf_read(&buf, cp.out, 1024))
493                         is_present = 1;
494
495                 close(cp.out);
496                 strbuf_release(&buf);
497         }
498         return is_present;
499 }
500
501 static void submodule_collect_changed_cb(struct diff_queue_struct *q,
502                                          struct diff_options *options,
503                                          void *data)
504 {
505         int i;
506         for (i = 0; i < q->nr; i++) {
507                 struct diff_filepair *p = q->queue[i];
508                 if (!S_ISGITLINK(p->two->mode))
509                         continue;
510
511                 if (S_ISGITLINK(p->one->mode)) {
512                         /* NEEDSWORK: We should honor the name configured in
513                          * the .gitmodules file of the commit we are examining
514                          * here to be able to correctly follow submodules
515                          * being moved around. */
516                         struct string_list_item *path;
517                         path = unsorted_string_list_lookup(&changed_submodule_paths, p->two->path);
518                         if (!path && !is_submodule_commit_present(p->two->path, p->two->sha1))
519                                 string_list_append(&changed_submodule_paths, xstrdup(p->two->path));
520                 } else {
521                         /* Submodule is new or was moved here */
522                         /* NEEDSWORK: When the .git directories of submodules
523                          * live inside the superprojects .git directory some
524                          * day we should fetch new submodules directly into
525                          * that location too when config or options request
526                          * that so they can be checked out from there. */
527                         continue;
528                 }
529         }
530 }
531
532 static int add_sha1_to_array(const char *ref, const unsigned char *sha1,
533                              int flags, void *data)
534 {
535         sha1_array_append(data, sha1);
536         return 0;
537 }
538
539 void check_for_new_submodule_commits(unsigned char new_sha1[20])
540 {
541         if (!initialized_fetch_ref_tips) {
542                 for_each_ref(add_sha1_to_array, &ref_tips_before_fetch);
543                 initialized_fetch_ref_tips = 1;
544         }
545
546         sha1_array_append(&ref_tips_after_fetch, new_sha1);
547 }
548
549 static void add_sha1_to_argv(const unsigned char sha1[20], void *data)
550 {
551         argv_array_push(data, sha1_to_hex(sha1));
552 }
553
554 static void calculate_changed_submodule_paths(void)
555 {
556         struct rev_info rev;
557         struct commit *commit;
558         struct argv_array argv = ARGV_ARRAY_INIT;
559
560         /* No need to check if there are no submodules configured */
561         if (!config_name_for_path.nr)
562                 return;
563
564         init_revisions(&rev, NULL);
565         argv_array_push(&argv, "--"); /* argv[0] program name */
566         sha1_array_for_each_unique(&ref_tips_after_fetch,
567                                    add_sha1_to_argv, &argv);
568         argv_array_push(&argv, "--not");
569         sha1_array_for_each_unique(&ref_tips_before_fetch,
570                                    add_sha1_to_argv, &argv);
571         setup_revisions(argv.argc, argv.argv, &rev, NULL);
572         if (prepare_revision_walk(&rev))
573                 die("revision walk setup failed");
574
575         /*
576          * Collect all submodules (whether checked out or not) for which new
577          * commits have been recorded upstream in "changed_submodule_paths".
578          */
579         while ((commit = get_revision(&rev))) {
580                 struct commit_list *parent = commit->parents;
581                 while (parent) {
582                         struct diff_options diff_opts;
583                         diff_setup(&diff_opts);
584                         DIFF_OPT_SET(&diff_opts, RECURSIVE);
585                         diff_opts.output_format |= DIFF_FORMAT_CALLBACK;
586                         diff_opts.format_callback = submodule_collect_changed_cb;
587                         diff_setup_done(&diff_opts);
588                         diff_tree_sha1(parent->item->object.sha1, commit->object.sha1, "", &diff_opts);
589                         diffcore_std(&diff_opts);
590                         diff_flush(&diff_opts);
591                         parent = parent->next;
592                 }
593         }
594
595         argv_array_clear(&argv);
596         sha1_array_clear(&ref_tips_before_fetch);
597         sha1_array_clear(&ref_tips_after_fetch);
598         initialized_fetch_ref_tips = 0;
599 }
600
601 int fetch_populated_submodules(const struct argv_array *options,
602                                const char *prefix, int command_line_option,
603                                int quiet)
604 {
605         int i, result = 0;
606         struct child_process cp;
607         struct argv_array argv = ARGV_ARRAY_INIT;
608         struct string_list_item *name_for_path;
609         const char *work_tree = get_git_work_tree();
610         if (!work_tree)
611                 goto out;
612
613         if (read_cache() < 0)
614                 die("index file corrupt");
615
616         argv_array_push(&argv, "fetch");
617         for (i = 0; i < options->argc; i++)
618                 argv_array_push(&argv, options->argv[i]);
619         argv_array_push(&argv, "--recurse-submodules-default");
620         /* default value, "--submodule-prefix" and its value are added later */
621
622         memset(&cp, 0, sizeof(cp));
623         cp.env = local_repo_env;
624         cp.git_cmd = 1;
625         cp.no_stdin = 1;
626
627         calculate_changed_submodule_paths();
628
629         for (i = 0; i < active_nr; i++) {
630                 struct strbuf submodule_path = STRBUF_INIT;
631                 struct strbuf submodule_git_dir = STRBUF_INIT;
632                 struct strbuf submodule_prefix = STRBUF_INIT;
633                 const struct cache_entry *ce = active_cache[i];
634                 const char *git_dir, *name, *default_argv;
635
636                 if (!S_ISGITLINK(ce->ce_mode))
637                         continue;
638
639                 name = ce->name;
640                 name_for_path = unsorted_string_list_lookup(&config_name_for_path, ce->name);
641                 if (name_for_path)
642                         name = name_for_path->util;
643
644                 default_argv = "yes";
645                 if (command_line_option == RECURSE_SUBMODULES_DEFAULT) {
646                         struct string_list_item *fetch_recurse_submodules_option;
647                         fetch_recurse_submodules_option = unsorted_string_list_lookup(&config_fetch_recurse_submodules_for_name, name);
648                         if (fetch_recurse_submodules_option) {
649                                 if ((intptr_t)fetch_recurse_submodules_option->util == RECURSE_SUBMODULES_OFF)
650                                         continue;
651                                 if ((intptr_t)fetch_recurse_submodules_option->util == RECURSE_SUBMODULES_ON_DEMAND) {
652                                         if (!unsorted_string_list_lookup(&changed_submodule_paths, ce->name))
653                                                 continue;
654                                         default_argv = "on-demand";
655                                 }
656                         } else {
657                                 if ((config_fetch_recurse_submodules == RECURSE_SUBMODULES_OFF) ||
658                                     gitmodules_is_unmerged)
659                                         continue;
660                                 if (config_fetch_recurse_submodules == RECURSE_SUBMODULES_ON_DEMAND) {
661                                         if (!unsorted_string_list_lookup(&changed_submodule_paths, ce->name))
662                                                 continue;
663                                         default_argv = "on-demand";
664                                 }
665                         }
666                 } else if (command_line_option == RECURSE_SUBMODULES_ON_DEMAND) {
667                         if (!unsorted_string_list_lookup(&changed_submodule_paths, ce->name))
668                                 continue;
669                         default_argv = "on-demand";
670                 }
671
672                 strbuf_addf(&submodule_path, "%s/%s", work_tree, ce->name);
673                 strbuf_addf(&submodule_git_dir, "%s/.git", submodule_path.buf);
674                 strbuf_addf(&submodule_prefix, "%s%s/", prefix, ce->name);
675                 git_dir = read_gitfile(submodule_git_dir.buf);
676                 if (!git_dir)
677                         git_dir = submodule_git_dir.buf;
678                 if (is_directory(git_dir)) {
679                         if (!quiet)
680                                 printf("Fetching submodule %s%s\n", prefix, ce->name);
681                         cp.dir = submodule_path.buf;
682                         argv_array_push(&argv, default_argv);
683                         argv_array_push(&argv, "--submodule-prefix");
684                         argv_array_push(&argv, submodule_prefix.buf);
685                         cp.argv = argv.argv;
686                         if (run_command(&cp))
687                                 result = 1;
688                         argv_array_pop(&argv);
689                         argv_array_pop(&argv);
690                         argv_array_pop(&argv);
691                 }
692                 strbuf_release(&submodule_path);
693                 strbuf_release(&submodule_git_dir);
694                 strbuf_release(&submodule_prefix);
695         }
696         argv_array_clear(&argv);
697 out:
698         string_list_clear(&changed_submodule_paths, 1);
699         return result;
700 }
701
702 unsigned is_submodule_modified(const char *path, int ignore_untracked)
703 {
704         ssize_t len;
705         struct child_process cp;
706         const char *argv[] = {
707                 "status",
708                 "--porcelain",
709                 NULL,
710                 NULL,
711         };
712         struct strbuf buf = STRBUF_INIT;
713         unsigned dirty_submodule = 0;
714         const char *line, *next_line;
715         const char *git_dir;
716
717         strbuf_addf(&buf, "%s/.git", path);
718         git_dir = read_gitfile(buf.buf);
719         if (!git_dir)
720                 git_dir = buf.buf;
721         if (!is_directory(git_dir)) {
722                 strbuf_release(&buf);
723                 /* The submodule is not checked out, so it is not modified */
724                 return 0;
725
726         }
727         strbuf_reset(&buf);
728
729         if (ignore_untracked)
730                 argv[2] = "-uno";
731
732         memset(&cp, 0, sizeof(cp));
733         cp.argv = argv;
734         cp.env = local_repo_env;
735         cp.git_cmd = 1;
736         cp.no_stdin = 1;
737         cp.out = -1;
738         cp.dir = path;
739         if (start_command(&cp))
740                 die("Could not run 'git status --porcelain' in submodule %s", path);
741
742         len = strbuf_read(&buf, cp.out, 1024);
743         line = buf.buf;
744         while (len > 2) {
745                 if ((line[0] == '?') && (line[1] == '?')) {
746                         dirty_submodule |= DIRTY_SUBMODULE_UNTRACKED;
747                         if (dirty_submodule & DIRTY_SUBMODULE_MODIFIED)
748                                 break;
749                 } else {
750                         dirty_submodule |= DIRTY_SUBMODULE_MODIFIED;
751                         if (ignore_untracked ||
752                             (dirty_submodule & DIRTY_SUBMODULE_UNTRACKED))
753                                 break;
754                 }
755                 next_line = strchr(line, '\n');
756                 if (!next_line)
757                         break;
758                 next_line++;
759                 len -= (next_line - line);
760                 line = next_line;
761         }
762         close(cp.out);
763
764         if (finish_command(&cp))
765                 die("'git status --porcelain' failed in submodule %s", path);
766
767         strbuf_release(&buf);
768         return dirty_submodule;
769 }
770
771 int submodule_uses_gitfile(const char *path)
772 {
773         struct child_process cp;
774         const char *argv[] = {
775                 "submodule",
776                 "foreach",
777                 "--quiet",
778                 "--recursive",
779                 "test -f .git",
780                 NULL,
781         };
782         struct strbuf buf = STRBUF_INIT;
783         const char *git_dir;
784
785         strbuf_addf(&buf, "%s/.git", path);
786         git_dir = read_gitfile(buf.buf);
787         if (!git_dir) {
788                 strbuf_release(&buf);
789                 return 0;
790         }
791         strbuf_release(&buf);
792
793         /* Now test that all nested submodules use a gitfile too */
794         memset(&cp, 0, sizeof(cp));
795         cp.argv = argv;
796         cp.env = local_repo_env;
797         cp.git_cmd = 1;
798         cp.no_stdin = 1;
799         cp.no_stderr = 1;
800         cp.no_stdout = 1;
801         cp.dir = path;
802         if (run_command(&cp))
803                 return 0;
804
805         return 1;
806 }
807
808 int ok_to_remove_submodule(const char *path)
809 {
810         struct stat st;
811         ssize_t len;
812         struct child_process cp;
813         const char *argv[] = {
814                 "status",
815                 "--porcelain",
816                 "-u",
817                 "--ignore-submodules=none",
818                 NULL,
819         };
820         struct strbuf buf = STRBUF_INIT;
821         int ok_to_remove = 1;
822
823         if ((lstat(path, &st) < 0) || is_empty_dir(path))
824                 return 1;
825
826         if (!submodule_uses_gitfile(path))
827                 return 0;
828
829         memset(&cp, 0, sizeof(cp));
830         cp.argv = argv;
831         cp.env = local_repo_env;
832         cp.git_cmd = 1;
833         cp.no_stdin = 1;
834         cp.out = -1;
835         cp.dir = path;
836         if (start_command(&cp))
837                 die("Could not run 'git status --porcelain -uall --ignore-submodules=none' in submodule %s", path);
838
839         len = strbuf_read(&buf, cp.out, 1024);
840         if (len > 2)
841                 ok_to_remove = 0;
842         close(cp.out);
843
844         if (finish_command(&cp))
845                 die("'git status --porcelain -uall --ignore-submodules=none' failed in submodule %s", path);
846
847         strbuf_release(&buf);
848         return ok_to_remove;
849 }
850
851 static int find_first_merges(struct object_array *result, const char *path,
852                 struct commit *a, struct commit *b)
853 {
854         int i, j;
855         struct object_array merges = OBJECT_ARRAY_INIT;
856         struct commit *commit;
857         int contains_another;
858
859         char merged_revision[42];
860         const char *rev_args[] = { "rev-list", "--merges", "--ancestry-path",
861                                    "--all", merged_revision, NULL };
862         struct rev_info revs;
863         struct setup_revision_opt rev_opts;
864
865         memset(result, 0, sizeof(struct object_array));
866         memset(&rev_opts, 0, sizeof(rev_opts));
867
868         /* get all revisions that merge commit a */
869         snprintf(merged_revision, sizeof(merged_revision), "^%s",
870                         sha1_to_hex(a->object.sha1));
871         init_revisions(&revs, NULL);
872         rev_opts.submodule = path;
873         setup_revisions(sizeof(rev_args)/sizeof(char *)-1, rev_args, &revs, &rev_opts);
874
875         /* save all revisions from the above list that contain b */
876         if (prepare_revision_walk(&revs))
877                 die("revision walk setup failed");
878         while ((commit = get_revision(&revs)) != NULL) {
879                 struct object *o = &(commit->object);
880                 if (in_merge_bases(b, commit))
881                         add_object_array(o, NULL, &merges);
882         }
883         reset_revision_walk();
884
885         /* Now we've got all merges that contain a and b. Prune all
886          * merges that contain another found merge and save them in
887          * result.
888          */
889         for (i = 0; i < merges.nr; i++) {
890                 struct commit *m1 = (struct commit *) merges.objects[i].item;
891
892                 contains_another = 0;
893                 for (j = 0; j < merges.nr; j++) {
894                         struct commit *m2 = (struct commit *) merges.objects[j].item;
895                         if (i != j && in_merge_bases(m2, m1)) {
896                                 contains_another = 1;
897                                 break;
898                         }
899                 }
900
901                 if (!contains_another)
902                         add_object_array(merges.objects[i].item, NULL, result);
903         }
904
905         free(merges.objects);
906         return result->nr;
907 }
908
909 static void print_commit(struct commit *commit)
910 {
911         struct strbuf sb = STRBUF_INIT;
912         struct pretty_print_context ctx = {0};
913         ctx.date_mode = DATE_NORMAL;
914         format_commit_message(commit, " %h: %m %s", &sb, &ctx);
915         fprintf(stderr, "%s\n", sb.buf);
916         strbuf_release(&sb);
917 }
918
919 #define MERGE_WARNING(path, msg) \
920         warning("Failed to merge submodule %s (%s)", path, msg);
921
922 int merge_submodule(unsigned char result[20], const char *path,
923                     const unsigned char base[20], const unsigned char a[20],
924                     const unsigned char b[20], int search)
925 {
926         struct commit *commit_base, *commit_a, *commit_b;
927         int parent_count;
928         struct object_array merges;
929
930         int i;
931
932         /* store a in result in case we fail */
933         hashcpy(result, a);
934
935         /* we can not handle deletion conflicts */
936         if (is_null_sha1(base))
937                 return 0;
938         if (is_null_sha1(a))
939                 return 0;
940         if (is_null_sha1(b))
941                 return 0;
942
943         if (add_submodule_odb(path)) {
944                 MERGE_WARNING(path, "not checked out");
945                 return 0;
946         }
947
948         if (!(commit_base = lookup_commit_reference(base)) ||
949             !(commit_a = lookup_commit_reference(a)) ||
950             !(commit_b = lookup_commit_reference(b))) {
951                 MERGE_WARNING(path, "commits not present");
952                 return 0;
953         }
954
955         /* check whether both changes are forward */
956         if (!in_merge_bases(commit_base, commit_a) ||
957             !in_merge_bases(commit_base, commit_b)) {
958                 MERGE_WARNING(path, "commits don't follow merge-base");
959                 return 0;
960         }
961
962         /* Case #1: a is contained in b or vice versa */
963         if (in_merge_bases(commit_a, commit_b)) {
964                 hashcpy(result, b);
965                 return 1;
966         }
967         if (in_merge_bases(commit_b, commit_a)) {
968                 hashcpy(result, a);
969                 return 1;
970         }
971
972         /*
973          * Case #2: There are one or more merges that contain a and b in
974          * the submodule. If there is only one, then present it as a
975          * suggestion to the user, but leave it marked unmerged so the
976          * user needs to confirm the resolution.
977          */
978
979         /* Skip the search if makes no sense to the calling context.  */
980         if (!search)
981                 return 0;
982
983         /* find commit which merges them */
984         parent_count = find_first_merges(&merges, path, commit_a, commit_b);
985         switch (parent_count) {
986         case 0:
987                 MERGE_WARNING(path, "merge following commits not found");
988                 break;
989
990         case 1:
991                 MERGE_WARNING(path, "not fast-forward");
992                 fprintf(stderr, "Found a possible merge resolution "
993                                 "for the submodule:\n");
994                 print_commit((struct commit *) merges.objects[0].item);
995                 fprintf(stderr,
996                         "If this is correct simply add it to the index "
997                         "for example\n"
998                         "by using:\n\n"
999                         "  git update-index --cacheinfo 160000 %s \"%s\"\n\n"
1000                         "which will accept this suggestion.\n",
1001                         sha1_to_hex(merges.objects[0].item->sha1), path);
1002                 break;
1003
1004         default:
1005                 MERGE_WARNING(path, "multiple merges found");
1006                 for (i = 0; i < merges.nr; i++)
1007                         print_commit((struct commit *) merges.objects[i].item);
1008         }
1009
1010         free(merges.objects);
1011         return 0;
1012 }