Merge branch 'bc/commit-invalid-utf8'
[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                 config = unsorted_string_list_lookup(&config_name_for_path, value);
138                 if (config)
139                         free(config->util);
140                 else
141                         config = string_list_append(&config_name_for_path, xstrdup(value));
142                 config->util = xmemdupz(name, namelen);
143         } else if (!strcmp(key, "fetchrecursesubmodules")) {
144                 char *name_cstr = xmemdupz(name, namelen);
145                 config = unsorted_string_list_lookup(&config_fetch_recurse_submodules_for_name, name_cstr);
146                 if (!config)
147                         config = string_list_append(&config_fetch_recurse_submodules_for_name, name_cstr);
148                 else
149                         free(name_cstr);
150                 config->util = (void *)(intptr_t)parse_fetch_recurse_submodules_arg(var, value);
151         } else if (!strcmp(key, "ignore")) {
152                 char *name_cstr;
153
154                 if (strcmp(value, "untracked") && strcmp(value, "dirty") &&
155                     strcmp(value, "all") && strcmp(value, "none")) {
156                         warning("Invalid parameter \"%s\" for config option \"submodule.%s.ignore\"", value, var);
157                         return 0;
158                 }
159
160                 name_cstr = xmemdupz(name, namelen);
161                 config = unsorted_string_list_lookup(&config_ignore_for_name, name_cstr);
162                 if (config) {
163                         free(config->util);
164                         free(name_cstr);
165                 } else
166                         config = string_list_append(&config_ignore_for_name, name_cstr);
167                 config->util = xstrdup(value);
168                 return 0;
169         }
170         return 0;
171 }
172
173 void handle_ignore_submodules_arg(struct diff_options *diffopt,
174                                   const char *arg)
175 {
176         DIFF_OPT_CLR(diffopt, IGNORE_SUBMODULES);
177         DIFF_OPT_CLR(diffopt, IGNORE_UNTRACKED_IN_SUBMODULES);
178         DIFF_OPT_CLR(diffopt, IGNORE_DIRTY_SUBMODULES);
179
180         if (!strcmp(arg, "all"))
181                 DIFF_OPT_SET(diffopt, IGNORE_SUBMODULES);
182         else if (!strcmp(arg, "untracked"))
183                 DIFF_OPT_SET(diffopt, IGNORE_UNTRACKED_IN_SUBMODULES);
184         else if (!strcmp(arg, "dirty"))
185                 DIFF_OPT_SET(diffopt, IGNORE_DIRTY_SUBMODULES);
186         else if (strcmp(arg, "none"))
187                 die("bad --ignore-submodules argument: %s", arg);
188 }
189
190 static int prepare_submodule_summary(struct rev_info *rev, const char *path,
191                 struct commit *left, struct commit *right,
192                 int *fast_forward, int *fast_backward)
193 {
194         struct commit_list *merge_bases, *list;
195
196         init_revisions(rev, NULL);
197         setup_revisions(0, NULL, rev, NULL);
198         rev->left_right = 1;
199         rev->first_parent_only = 1;
200         left->object.flags |= SYMMETRIC_LEFT;
201         add_pending_object(rev, &left->object, path);
202         add_pending_object(rev, &right->object, path);
203         merge_bases = get_merge_bases(left, right, 1);
204         if (merge_bases) {
205                 if (merge_bases->item == left)
206                         *fast_forward = 1;
207                 else if (merge_bases->item == right)
208                         *fast_backward = 1;
209         }
210         for (list = merge_bases; list; list = list->next) {
211                 list->item->object.flags |= UNINTERESTING;
212                 add_pending_object(rev, &list->item->object,
213                         sha1_to_hex(list->item->object.sha1));
214         }
215         return prepare_revision_walk(rev);
216 }
217
218 static void print_submodule_summary(struct rev_info *rev, FILE *f,
219                 const char *line_prefix,
220                 const char *del, const char *add, const char *reset)
221 {
222         static const char format[] = "  %m %s";
223         struct strbuf sb = STRBUF_INIT;
224         struct commit *commit;
225
226         while ((commit = get_revision(rev))) {
227                 struct pretty_print_context ctx = {0};
228                 ctx.date_mode = rev->date_mode;
229                 ctx.output_encoding = get_log_output_encoding();
230                 strbuf_setlen(&sb, 0);
231                 strbuf_addstr(&sb, line_prefix);
232                 if (commit->object.flags & SYMMETRIC_LEFT) {
233                         if (del)
234                                 strbuf_addstr(&sb, del);
235                 }
236                 else if (add)
237                         strbuf_addstr(&sb, add);
238                 format_commit_message(commit, format, &sb, &ctx);
239                 if (reset)
240                         strbuf_addstr(&sb, reset);
241                 strbuf_addch(&sb, '\n');
242                 fprintf(f, "%s", sb.buf);
243         }
244         strbuf_release(&sb);
245 }
246
247 int parse_fetch_recurse_submodules_arg(const char *opt, const char *arg)
248 {
249         switch (git_config_maybe_bool(opt, arg)) {
250         case 1:
251                 return RECURSE_SUBMODULES_ON;
252         case 0:
253                 return RECURSE_SUBMODULES_OFF;
254         default:
255                 if (!strcmp(arg, "on-demand"))
256                         return RECURSE_SUBMODULES_ON_DEMAND;
257                 die("bad %s argument: %s", opt, arg);
258         }
259 }
260
261 void show_submodule_summary(FILE *f, const char *path,
262                 const char *line_prefix,
263                 unsigned char one[20], unsigned char two[20],
264                 unsigned dirty_submodule, const char *meta,
265                 const char *del, const char *add, const char *reset)
266 {
267         struct rev_info rev;
268         struct commit *left = NULL, *right = NULL;
269         const char *message = NULL;
270         struct strbuf sb = STRBUF_INIT;
271         int fast_forward = 0, fast_backward = 0;
272
273         if (is_null_sha1(two))
274                 message = "(submodule deleted)";
275         else if (add_submodule_odb(path))
276                 message = "(not checked out)";
277         else if (is_null_sha1(one))
278                 message = "(new submodule)";
279         else if (!(left = lookup_commit_reference(one)) ||
280                  !(right = lookup_commit_reference(two)))
281                 message = "(commits not present)";
282         else if (prepare_submodule_summary(&rev, path, left, right,
283                                            &fast_forward, &fast_backward))
284                 message = "(revision walker failed)";
285
286         if (dirty_submodule & DIRTY_SUBMODULE_UNTRACKED)
287                 fprintf(f, "%sSubmodule %s contains untracked content\n",
288                         line_prefix, path);
289         if (dirty_submodule & DIRTY_SUBMODULE_MODIFIED)
290                 fprintf(f, "%sSubmodule %s contains modified content\n",
291                         line_prefix, path);
292
293         if (!hashcmp(one, two)) {
294                 strbuf_release(&sb);
295                 return;
296         }
297
298         strbuf_addf(&sb, "%s%sSubmodule %s %s..", line_prefix, meta, path,
299                         find_unique_abbrev(one, DEFAULT_ABBREV));
300         if (!fast_backward && !fast_forward)
301                 strbuf_addch(&sb, '.');
302         strbuf_addf(&sb, "%s", find_unique_abbrev(two, DEFAULT_ABBREV));
303         if (message)
304                 strbuf_addf(&sb, " %s%s\n", message, reset);
305         else
306                 strbuf_addf(&sb, "%s:%s\n", fast_backward ? " (rewind)" : "", reset);
307         fwrite(sb.buf, sb.len, 1, f);
308
309         if (!message) /* only NULL if we succeeded in setting up the walk */
310                 print_submodule_summary(&rev, f, line_prefix, del, add, reset);
311         if (left)
312                 clear_commit_marks(left, ~0);
313         if (right)
314                 clear_commit_marks(right, ~0);
315
316         strbuf_release(&sb);
317 }
318
319 void set_config_fetch_recurse_submodules(int value)
320 {
321         config_fetch_recurse_submodules = value;
322 }
323
324 static int has_remote(const char *refname, const unsigned char *sha1, int flags, void *cb_data)
325 {
326         return 1;
327 }
328
329 static int submodule_needs_pushing(const char *path, const unsigned char sha1[20])
330 {
331         if (add_submodule_odb(path) || !lookup_commit_reference(sha1))
332                 return 0;
333
334         if (for_each_remote_ref_submodule(path, has_remote, NULL) > 0) {
335                 struct child_process cp;
336                 const char *argv[] = {"rev-list", NULL, "--not", "--remotes", "-n", "1" , NULL};
337                 struct strbuf buf = STRBUF_INIT;
338                 int needs_pushing = 0;
339
340                 argv[1] = sha1_to_hex(sha1);
341                 memset(&cp, 0, sizeof(cp));
342                 cp.argv = argv;
343                 cp.env = local_repo_env;
344                 cp.git_cmd = 1;
345                 cp.no_stdin = 1;
346                 cp.out = -1;
347                 cp.dir = path;
348                 if (start_command(&cp))
349                         die("Could not run 'git rev-list %s --not --remotes -n 1' command in submodule %s",
350                                 sha1_to_hex(sha1), path);
351                 if (strbuf_read(&buf, cp.out, 41))
352                         needs_pushing = 1;
353                 finish_command(&cp);
354                 close(cp.out);
355                 strbuf_release(&buf);
356                 return needs_pushing;
357         }
358
359         return 0;
360 }
361
362 static void collect_submodules_from_diff(struct diff_queue_struct *q,
363                                          struct diff_options *options,
364                                          void *data)
365 {
366         int i;
367         struct string_list *needs_pushing = data;
368
369         for (i = 0; i < q->nr; i++) {
370                 struct diff_filepair *p = q->queue[i];
371                 if (!S_ISGITLINK(p->two->mode))
372                         continue;
373                 if (submodule_needs_pushing(p->two->path, p->two->sha1))
374                         string_list_insert(needs_pushing, p->two->path);
375         }
376 }
377
378 static void find_unpushed_submodule_commits(struct commit *commit,
379                 struct string_list *needs_pushing)
380 {
381         struct rev_info rev;
382
383         init_revisions(&rev, NULL);
384         rev.diffopt.output_format |= DIFF_FORMAT_CALLBACK;
385         rev.diffopt.format_callback = collect_submodules_from_diff;
386         rev.diffopt.format_callback_data = needs_pushing;
387         diff_tree_combined_merge(commit, 1, &rev);
388 }
389
390 int find_unpushed_submodules(unsigned char new_sha1[20],
391                 const char *remotes_name, struct string_list *needs_pushing)
392 {
393         struct rev_info rev;
394         struct commit *commit;
395         const char *argv[] = {NULL, NULL, "--not", "NULL", NULL};
396         int argc = ARRAY_SIZE(argv) - 1;
397         char *sha1_copy;
398
399         struct strbuf remotes_arg = STRBUF_INIT;
400
401         strbuf_addf(&remotes_arg, "--remotes=%s", remotes_name);
402         init_revisions(&rev, NULL);
403         sha1_copy = xstrdup(sha1_to_hex(new_sha1));
404         argv[1] = sha1_copy;
405         argv[3] = remotes_arg.buf;
406         setup_revisions(argc, argv, &rev, NULL);
407         if (prepare_revision_walk(&rev))
408                 die("revision walk setup failed");
409
410         while ((commit = get_revision(&rev)) != NULL)
411                 find_unpushed_submodule_commits(commit, needs_pushing);
412
413         reset_revision_walk();
414         free(sha1_copy);
415         strbuf_release(&remotes_arg);
416
417         return needs_pushing->nr;
418 }
419
420 static int push_submodule(const char *path)
421 {
422         if (add_submodule_odb(path))
423                 return 1;
424
425         if (for_each_remote_ref_submodule(path, has_remote, NULL) > 0) {
426                 struct child_process cp;
427                 const char *argv[] = {"push", NULL};
428
429                 memset(&cp, 0, sizeof(cp));
430                 cp.argv = argv;
431                 cp.env = local_repo_env;
432                 cp.git_cmd = 1;
433                 cp.no_stdin = 1;
434                 cp.dir = path;
435                 if (run_command(&cp))
436                         return 0;
437                 close(cp.out);
438         }
439
440         return 1;
441 }
442
443 int push_unpushed_submodules(unsigned char new_sha1[20], const char *remotes_name)
444 {
445         int i, ret = 1;
446         struct string_list needs_pushing;
447
448         memset(&needs_pushing, 0, sizeof(struct string_list));
449         needs_pushing.strdup_strings = 1;
450
451         if (!find_unpushed_submodules(new_sha1, remotes_name, &needs_pushing))
452                 return 1;
453
454         for (i = 0; i < needs_pushing.nr; i++) {
455                 const char *path = needs_pushing.items[i].string;
456                 fprintf(stderr, "Pushing submodule '%s'\n", path);
457                 if (!push_submodule(path)) {
458                         fprintf(stderr, "Unable to push submodule '%s'\n", path);
459                         ret = 0;
460                 }
461         }
462
463         string_list_clear(&needs_pushing, 0);
464
465         return ret;
466 }
467
468 static int is_submodule_commit_present(const char *path, unsigned char sha1[20])
469 {
470         int is_present = 0;
471         if (!add_submodule_odb(path) && lookup_commit_reference(sha1)) {
472                 /* Even if the submodule is checked out and the commit is
473                  * present, make sure it is reachable from a ref. */
474                 struct child_process cp;
475                 const char *argv[] = {"rev-list", "-n", "1", NULL, "--not", "--all", NULL};
476                 struct strbuf buf = STRBUF_INIT;
477
478                 argv[3] = sha1_to_hex(sha1);
479                 memset(&cp, 0, sizeof(cp));
480                 cp.argv = argv;
481                 cp.env = local_repo_env;
482                 cp.git_cmd = 1;
483                 cp.no_stdin = 1;
484                 cp.out = -1;
485                 cp.dir = path;
486                 if (!run_command(&cp) && !strbuf_read(&buf, cp.out, 1024))
487                         is_present = 1;
488
489                 close(cp.out);
490                 strbuf_release(&buf);
491         }
492         return is_present;
493 }
494
495 static void submodule_collect_changed_cb(struct diff_queue_struct *q,
496                                          struct diff_options *options,
497                                          void *data)
498 {
499         int i;
500         for (i = 0; i < q->nr; i++) {
501                 struct diff_filepair *p = q->queue[i];
502                 if (!S_ISGITLINK(p->two->mode))
503                         continue;
504
505                 if (S_ISGITLINK(p->one->mode)) {
506                         /* NEEDSWORK: We should honor the name configured in
507                          * the .gitmodules file of the commit we are examining
508                          * here to be able to correctly follow submodules
509                          * being moved around. */
510                         struct string_list_item *path;
511                         path = unsorted_string_list_lookup(&changed_submodule_paths, p->two->path);
512                         if (!path && !is_submodule_commit_present(p->two->path, p->two->sha1))
513                                 string_list_append(&changed_submodule_paths, xstrdup(p->two->path));
514                 } else {
515                         /* Submodule is new or was moved here */
516                         /* NEEDSWORK: When the .git directories of submodules
517                          * live inside the superprojects .git directory some
518                          * day we should fetch new submodules directly into
519                          * that location too when config or options request
520                          * that so they can be checked out from there. */
521                         continue;
522                 }
523         }
524 }
525
526 static int add_sha1_to_array(const char *ref, const unsigned char *sha1,
527                              int flags, void *data)
528 {
529         sha1_array_append(data, sha1);
530         return 0;
531 }
532
533 void check_for_new_submodule_commits(unsigned char new_sha1[20])
534 {
535         if (!initialized_fetch_ref_tips) {
536                 for_each_ref(add_sha1_to_array, &ref_tips_before_fetch);
537                 initialized_fetch_ref_tips = 1;
538         }
539
540         sha1_array_append(&ref_tips_after_fetch, new_sha1);
541 }
542
543 static void add_sha1_to_argv(const unsigned char sha1[20], void *data)
544 {
545         argv_array_push(data, sha1_to_hex(sha1));
546 }
547
548 static void calculate_changed_submodule_paths(void)
549 {
550         struct rev_info rev;
551         struct commit *commit;
552         struct argv_array argv = ARGV_ARRAY_INIT;
553
554         /* No need to check if there are no submodules configured */
555         if (!config_name_for_path.nr)
556                 return;
557
558         init_revisions(&rev, NULL);
559         argv_array_push(&argv, "--"); /* argv[0] program name */
560         sha1_array_for_each_unique(&ref_tips_after_fetch,
561                                    add_sha1_to_argv, &argv);
562         argv_array_push(&argv, "--not");
563         sha1_array_for_each_unique(&ref_tips_before_fetch,
564                                    add_sha1_to_argv, &argv);
565         setup_revisions(argv.argc, argv.argv, &rev, NULL);
566         if (prepare_revision_walk(&rev))
567                 die("revision walk setup failed");
568
569         /*
570          * Collect all submodules (whether checked out or not) for which new
571          * commits have been recorded upstream in "changed_submodule_paths".
572          */
573         while ((commit = get_revision(&rev))) {
574                 struct commit_list *parent = commit->parents;
575                 while (parent) {
576                         struct diff_options diff_opts;
577                         diff_setup(&diff_opts);
578                         DIFF_OPT_SET(&diff_opts, RECURSIVE);
579                         diff_opts.output_format |= DIFF_FORMAT_CALLBACK;
580                         diff_opts.format_callback = submodule_collect_changed_cb;
581                         diff_setup_done(&diff_opts);
582                         diff_tree_sha1(parent->item->object.sha1, commit->object.sha1, "", &diff_opts);
583                         diffcore_std(&diff_opts);
584                         diff_flush(&diff_opts);
585                         parent = parent->next;
586                 }
587         }
588
589         argv_array_clear(&argv);
590         sha1_array_clear(&ref_tips_before_fetch);
591         sha1_array_clear(&ref_tips_after_fetch);
592         initialized_fetch_ref_tips = 0;
593 }
594
595 int fetch_populated_submodules(const struct argv_array *options,
596                                const char *prefix, int command_line_option,
597                                int quiet)
598 {
599         int i, result = 0;
600         struct child_process cp;
601         struct argv_array argv = ARGV_ARRAY_INIT;
602         struct string_list_item *name_for_path;
603         const char *work_tree = get_git_work_tree();
604         if (!work_tree)
605                 goto out;
606
607         if (read_cache() < 0)
608                 die("index file corrupt");
609
610         argv_array_push(&argv, "fetch");
611         for (i = 0; i < options->argc; i++)
612                 argv_array_push(&argv, options->argv[i]);
613         argv_array_push(&argv, "--recurse-submodules-default");
614         /* default value, "--submodule-prefix" and its value are added later */
615
616         memset(&cp, 0, sizeof(cp));
617         cp.env = local_repo_env;
618         cp.git_cmd = 1;
619         cp.no_stdin = 1;
620
621         calculate_changed_submodule_paths();
622
623         for (i = 0; i < active_nr; i++) {
624                 struct strbuf submodule_path = STRBUF_INIT;
625                 struct strbuf submodule_git_dir = STRBUF_INIT;
626                 struct strbuf submodule_prefix = STRBUF_INIT;
627                 const struct cache_entry *ce = active_cache[i];
628                 const char *git_dir, *name, *default_argv;
629
630                 if (!S_ISGITLINK(ce->ce_mode))
631                         continue;
632
633                 name = ce->name;
634                 name_for_path = unsorted_string_list_lookup(&config_name_for_path, ce->name);
635                 if (name_for_path)
636                         name = name_for_path->util;
637
638                 default_argv = "yes";
639                 if (command_line_option == RECURSE_SUBMODULES_DEFAULT) {
640                         struct string_list_item *fetch_recurse_submodules_option;
641                         fetch_recurse_submodules_option = unsorted_string_list_lookup(&config_fetch_recurse_submodules_for_name, name);
642                         if (fetch_recurse_submodules_option) {
643                                 if ((intptr_t)fetch_recurse_submodules_option->util == RECURSE_SUBMODULES_OFF)
644                                         continue;
645                                 if ((intptr_t)fetch_recurse_submodules_option->util == RECURSE_SUBMODULES_ON_DEMAND) {
646                                         if (!unsorted_string_list_lookup(&changed_submodule_paths, ce->name))
647                                                 continue;
648                                         default_argv = "on-demand";
649                                 }
650                         } else {
651                                 if ((config_fetch_recurse_submodules == RECURSE_SUBMODULES_OFF) ||
652                                     gitmodules_is_unmerged)
653                                         continue;
654                                 if (config_fetch_recurse_submodules == RECURSE_SUBMODULES_ON_DEMAND) {
655                                         if (!unsorted_string_list_lookup(&changed_submodule_paths, ce->name))
656                                                 continue;
657                                         default_argv = "on-demand";
658                                 }
659                         }
660                 } else if (command_line_option == 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                 strbuf_addf(&submodule_path, "%s/%s", work_tree, ce->name);
667                 strbuf_addf(&submodule_git_dir, "%s/.git", submodule_path.buf);
668                 strbuf_addf(&submodule_prefix, "%s%s/", prefix, ce->name);
669                 git_dir = read_gitfile(submodule_git_dir.buf);
670                 if (!git_dir)
671                         git_dir = submodule_git_dir.buf;
672                 if (is_directory(git_dir)) {
673                         if (!quiet)
674                                 printf("Fetching submodule %s%s\n", prefix, ce->name);
675                         cp.dir = submodule_path.buf;
676                         argv_array_push(&argv, default_argv);
677                         argv_array_push(&argv, "--submodule-prefix");
678                         argv_array_push(&argv, submodule_prefix.buf);
679                         cp.argv = argv.argv;
680                         if (run_command(&cp))
681                                 result = 1;
682                         argv_array_pop(&argv);
683                         argv_array_pop(&argv);
684                         argv_array_pop(&argv);
685                 }
686                 strbuf_release(&submodule_path);
687                 strbuf_release(&submodule_git_dir);
688                 strbuf_release(&submodule_prefix);
689         }
690         argv_array_clear(&argv);
691 out:
692         string_list_clear(&changed_submodule_paths, 1);
693         return result;
694 }
695
696 unsigned is_submodule_modified(const char *path, int ignore_untracked)
697 {
698         ssize_t len;
699         struct child_process cp;
700         const char *argv[] = {
701                 "status",
702                 "--porcelain",
703                 NULL,
704                 NULL,
705         };
706         struct strbuf buf = STRBUF_INIT;
707         unsigned dirty_submodule = 0;
708         const char *line, *next_line;
709         const char *git_dir;
710
711         strbuf_addf(&buf, "%s/.git", path);
712         git_dir = read_gitfile(buf.buf);
713         if (!git_dir)
714                 git_dir = buf.buf;
715         if (!is_directory(git_dir)) {
716                 strbuf_release(&buf);
717                 /* The submodule is not checked out, so it is not modified */
718                 return 0;
719
720         }
721         strbuf_reset(&buf);
722
723         if (ignore_untracked)
724                 argv[2] = "-uno";
725
726         memset(&cp, 0, sizeof(cp));
727         cp.argv = argv;
728         cp.env = local_repo_env;
729         cp.git_cmd = 1;
730         cp.no_stdin = 1;
731         cp.out = -1;
732         cp.dir = path;
733         if (start_command(&cp))
734                 die("Could not run 'git status --porcelain' in submodule %s", path);
735
736         len = strbuf_read(&buf, cp.out, 1024);
737         line = buf.buf;
738         while (len > 2) {
739                 if ((line[0] == '?') && (line[1] == '?')) {
740                         dirty_submodule |= DIRTY_SUBMODULE_UNTRACKED;
741                         if (dirty_submodule & DIRTY_SUBMODULE_MODIFIED)
742                                 break;
743                 } else {
744                         dirty_submodule |= DIRTY_SUBMODULE_MODIFIED;
745                         if (ignore_untracked ||
746                             (dirty_submodule & DIRTY_SUBMODULE_UNTRACKED))
747                                 break;
748                 }
749                 next_line = strchr(line, '\n');
750                 if (!next_line)
751                         break;
752                 next_line++;
753                 len -= (next_line - line);
754                 line = next_line;
755         }
756         close(cp.out);
757
758         if (finish_command(&cp))
759                 die("'git status --porcelain' failed in submodule %s", path);
760
761         strbuf_release(&buf);
762         return dirty_submodule;
763 }
764
765 int submodule_uses_gitfile(const char *path)
766 {
767         struct child_process cp;
768         const char *argv[] = {
769                 "submodule",
770                 "foreach",
771                 "--quiet",
772                 "--recursive",
773                 "test -f .git",
774                 NULL,
775         };
776         struct strbuf buf = STRBUF_INIT;
777         const char *git_dir;
778
779         strbuf_addf(&buf, "%s/.git", path);
780         git_dir = read_gitfile(buf.buf);
781         if (!git_dir) {
782                 strbuf_release(&buf);
783                 return 0;
784         }
785         strbuf_release(&buf);
786
787         /* Now test that all nested submodules use a gitfile too */
788         memset(&cp, 0, sizeof(cp));
789         cp.argv = argv;
790         cp.env = local_repo_env;
791         cp.git_cmd = 1;
792         cp.no_stdin = 1;
793         cp.no_stderr = 1;
794         cp.no_stdout = 1;
795         cp.dir = path;
796         if (run_command(&cp))
797                 return 0;
798
799         return 1;
800 }
801
802 int ok_to_remove_submodule(const char *path)
803 {
804         struct stat st;
805         ssize_t len;
806         struct child_process cp;
807         const char *argv[] = {
808                 "status",
809                 "--porcelain",
810                 "-u",
811                 "--ignore-submodules=none",
812                 NULL,
813         };
814         struct strbuf buf = STRBUF_INIT;
815         int ok_to_remove = 1;
816
817         if ((lstat(path, &st) < 0) || is_empty_dir(path))
818                 return 1;
819
820         if (!submodule_uses_gitfile(path))
821                 return 0;
822
823         memset(&cp, 0, sizeof(cp));
824         cp.argv = argv;
825         cp.env = local_repo_env;
826         cp.git_cmd = 1;
827         cp.no_stdin = 1;
828         cp.out = -1;
829         cp.dir = path;
830         if (start_command(&cp))
831                 die("Could not run 'git status --porcelain -uall --ignore-submodules=none' in submodule %s", path);
832
833         len = strbuf_read(&buf, cp.out, 1024);
834         if (len > 2)
835                 ok_to_remove = 0;
836         close(cp.out);
837
838         if (finish_command(&cp))
839                 die("'git status --porcelain -uall --ignore-submodules=none' failed in submodule %s", path);
840
841         strbuf_release(&buf);
842         return ok_to_remove;
843 }
844
845 static int find_first_merges(struct object_array *result, const char *path,
846                 struct commit *a, struct commit *b)
847 {
848         int i, j;
849         struct object_array merges = OBJECT_ARRAY_INIT;
850         struct commit *commit;
851         int contains_another;
852
853         char merged_revision[42];
854         const char *rev_args[] = { "rev-list", "--merges", "--ancestry-path",
855                                    "--all", merged_revision, NULL };
856         struct rev_info revs;
857         struct setup_revision_opt rev_opts;
858
859         memset(result, 0, sizeof(struct object_array));
860         memset(&rev_opts, 0, sizeof(rev_opts));
861
862         /* get all revisions that merge commit a */
863         snprintf(merged_revision, sizeof(merged_revision), "^%s",
864                         sha1_to_hex(a->object.sha1));
865         init_revisions(&revs, NULL);
866         rev_opts.submodule = path;
867         setup_revisions(sizeof(rev_args)/sizeof(char *)-1, rev_args, &revs, &rev_opts);
868
869         /* save all revisions from the above list that contain b */
870         if (prepare_revision_walk(&revs))
871                 die("revision walk setup failed");
872         while ((commit = get_revision(&revs)) != NULL) {
873                 struct object *o = &(commit->object);
874                 if (in_merge_bases(b, commit))
875                         add_object_array(o, NULL, &merges);
876         }
877         reset_revision_walk();
878
879         /* Now we've got all merges that contain a and b. Prune all
880          * merges that contain another found merge and save them in
881          * result.
882          */
883         for (i = 0; i < merges.nr; i++) {
884                 struct commit *m1 = (struct commit *) merges.objects[i].item;
885
886                 contains_another = 0;
887                 for (j = 0; j < merges.nr; j++) {
888                         struct commit *m2 = (struct commit *) merges.objects[j].item;
889                         if (i != j && in_merge_bases(m2, m1)) {
890                                 contains_another = 1;
891                                 break;
892                         }
893                 }
894
895                 if (!contains_another)
896                         add_object_array(merges.objects[i].item, NULL, result);
897         }
898
899         free(merges.objects);
900         return result->nr;
901 }
902
903 static void print_commit(struct commit *commit)
904 {
905         struct strbuf sb = STRBUF_INIT;
906         struct pretty_print_context ctx = {0};
907         ctx.date_mode = DATE_NORMAL;
908         format_commit_message(commit, " %h: %m %s", &sb, &ctx);
909         fprintf(stderr, "%s\n", sb.buf);
910         strbuf_release(&sb);
911 }
912
913 #define MERGE_WARNING(path, msg) \
914         warning("Failed to merge submodule %s (%s)", path, msg);
915
916 int merge_submodule(unsigned char result[20], const char *path,
917                     const unsigned char base[20], const unsigned char a[20],
918                     const unsigned char b[20], int search)
919 {
920         struct commit *commit_base, *commit_a, *commit_b;
921         int parent_count;
922         struct object_array merges;
923
924         int i;
925
926         /* store a in result in case we fail */
927         hashcpy(result, a);
928
929         /* we can not handle deletion conflicts */
930         if (is_null_sha1(base))
931                 return 0;
932         if (is_null_sha1(a))
933                 return 0;
934         if (is_null_sha1(b))
935                 return 0;
936
937         if (add_submodule_odb(path)) {
938                 MERGE_WARNING(path, "not checked out");
939                 return 0;
940         }
941
942         if (!(commit_base = lookup_commit_reference(base)) ||
943             !(commit_a = lookup_commit_reference(a)) ||
944             !(commit_b = lookup_commit_reference(b))) {
945                 MERGE_WARNING(path, "commits not present");
946                 return 0;
947         }
948
949         /* check whether both changes are forward */
950         if (!in_merge_bases(commit_base, commit_a) ||
951             !in_merge_bases(commit_base, commit_b)) {
952                 MERGE_WARNING(path, "commits don't follow merge-base");
953                 return 0;
954         }
955
956         /* Case #1: a is contained in b or vice versa */
957         if (in_merge_bases(commit_a, commit_b)) {
958                 hashcpy(result, b);
959                 return 1;
960         }
961         if (in_merge_bases(commit_b, commit_a)) {
962                 hashcpy(result, a);
963                 return 1;
964         }
965
966         /*
967          * Case #2: There are one or more merges that contain a and b in
968          * the submodule. If there is only one, then present it as a
969          * suggestion to the user, but leave it marked unmerged so the
970          * user needs to confirm the resolution.
971          */
972
973         /* Skip the search if makes no sense to the calling context.  */
974         if (!search)
975                 return 0;
976
977         /* find commit which merges them */
978         parent_count = find_first_merges(&merges, path, commit_a, commit_b);
979         switch (parent_count) {
980         case 0:
981                 MERGE_WARNING(path, "merge following commits not found");
982                 break;
983
984         case 1:
985                 MERGE_WARNING(path, "not fast-forward");
986                 fprintf(stderr, "Found a possible merge resolution "
987                                 "for the submodule:\n");
988                 print_commit((struct commit *) merges.objects[0].item);
989                 fprintf(stderr,
990                         "If this is correct simply add it to the index "
991                         "for example\n"
992                         "by using:\n\n"
993                         "  git update-index --cacheinfo 160000 %s \"%s\"\n\n"
994                         "which will accept this suggestion.\n",
995                         sha1_to_hex(merges.objects[0].item->sha1), path);
996                 break;
997
998         default:
999                 MERGE_WARNING(path, "multiple merges found");
1000                 for (i = 0; i < merges.nr; i++)
1001                         print_commit((struct commit *) merges.objects[i].item);
1002         }
1003
1004         free(merges.objects);
1005         return 0;
1006 }