submodule.c: add .gitmodules staging helper functions
[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 #include "blob.h"
14
15 static struct string_list config_name_for_path;
16 static struct string_list config_fetch_recurse_submodules_for_name;
17 static struct string_list config_ignore_for_name;
18 static int config_fetch_recurse_submodules = RECURSE_SUBMODULES_ON_DEMAND;
19 static struct string_list changed_submodule_paths;
20 static int initialized_fetch_ref_tips;
21 static struct sha1_array ref_tips_before_fetch;
22 static struct sha1_array ref_tips_after_fetch;
23
24 /*
25  * The following flag is set if the .gitmodules file is unmerged. We then
26  * disable recursion for all submodules where .git/config doesn't have a
27  * matching config entry because we can't guess what might be configured in
28  * .gitmodules unless the user resolves the conflict. When a command line
29  * option is given (which always overrides configuration) this flag will be
30  * ignored.
31  */
32 static int gitmodules_is_unmerged;
33
34 /*
35  * This flag is set if the .gitmodules file had unstaged modifications on
36  * startup. This must be checked before allowing modifications to the
37  * .gitmodules file with the intention to stage them later, because when
38  * continuing we would stage the modifications the user didn't stage herself
39  * too. That might change in a future version when we learn to stage the
40  * changes we do ourselves without staging any previous modifications.
41  */
42 static int gitmodules_is_modified;
43
44
45 int is_staging_gitmodules_ok(void)
46 {
47         return !gitmodules_is_modified;
48 }
49
50 void stage_updated_gitmodules(void)
51 {
52         struct strbuf buf = STRBUF_INIT;
53         struct stat st;
54         int pos;
55         struct cache_entry *ce;
56         int namelen = strlen(".gitmodules");
57
58         pos = cache_name_pos(".gitmodules", namelen);
59         if (pos < 0) {
60                 warning(_("could not find .gitmodules in index"));
61                 return;
62         }
63         ce = active_cache[pos];
64         ce->ce_flags = namelen;
65         if (strbuf_read_file(&buf, ".gitmodules", 0) < 0)
66                 die(_("reading updated .gitmodules failed"));
67         if (lstat(".gitmodules", &st) < 0)
68                 die_errno(_("unable to stat updated .gitmodules"));
69         fill_stat_cache_info(ce, &st);
70         ce->ce_mode = ce_mode_from_stat(ce, st.st_mode);
71         if (remove_cache_entry_at(pos) < 0)
72                 die(_("unable to remove .gitmodules from index"));
73         if (write_sha1_file(buf.buf, buf.len, blob_type, ce->sha1))
74                 die(_("adding updated .gitmodules failed"));
75         if (add_cache_entry(ce, ADD_CACHE_OK_TO_ADD|ADD_CACHE_OK_TO_REPLACE))
76                 die(_("staging updated .gitmodules failed"));
77 }
78
79 static int add_submodule_odb(const char *path)
80 {
81         struct strbuf objects_directory = STRBUF_INIT;
82         struct alternate_object_database *alt_odb;
83         int ret = 0;
84         const char *git_dir;
85
86         strbuf_addf(&objects_directory, "%s/.git", path);
87         git_dir = read_gitfile(objects_directory.buf);
88         if (git_dir) {
89                 strbuf_reset(&objects_directory);
90                 strbuf_addstr(&objects_directory, git_dir);
91         }
92         strbuf_addstr(&objects_directory, "/objects/");
93         if (!is_directory(objects_directory.buf)) {
94                 ret = -1;
95                 goto done;
96         }
97         /* avoid adding it twice */
98         for (alt_odb = alt_odb_list; alt_odb; alt_odb = alt_odb->next)
99                 if (alt_odb->name - alt_odb->base == objects_directory.len &&
100                                 !strncmp(alt_odb->base, objects_directory.buf,
101                                         objects_directory.len))
102                         goto done;
103
104         alt_odb = xmalloc(objects_directory.len + 42 + sizeof(*alt_odb));
105         alt_odb->next = alt_odb_list;
106         strcpy(alt_odb->base, objects_directory.buf);
107         alt_odb->name = alt_odb->base + objects_directory.len;
108         alt_odb->name[2] = '/';
109         alt_odb->name[40] = '\0';
110         alt_odb->name[41] = '\0';
111         alt_odb_list = alt_odb;
112
113         /* add possible alternates from the submodule */
114         read_info_alternates(objects_directory.buf, 0);
115         prepare_alt_odb();
116 done:
117         strbuf_release(&objects_directory);
118         return ret;
119 }
120
121 void set_diffopt_flags_from_submodule_config(struct diff_options *diffopt,
122                                              const char *path)
123 {
124         struct string_list_item *path_option, *ignore_option;
125         path_option = unsorted_string_list_lookup(&config_name_for_path, path);
126         if (path_option) {
127                 ignore_option = unsorted_string_list_lookup(&config_ignore_for_name, path_option->util);
128                 if (ignore_option)
129                         handle_ignore_submodules_arg(diffopt, ignore_option->util);
130                 else if (gitmodules_is_unmerged)
131                         DIFF_OPT_SET(diffopt, IGNORE_SUBMODULES);
132         }
133 }
134
135 int submodule_config(const char *var, const char *value, void *cb)
136 {
137         if (!prefixcmp(var, "submodule."))
138                 return parse_submodule_config_option(var, value);
139         else if (!strcmp(var, "fetch.recursesubmodules")) {
140                 config_fetch_recurse_submodules = parse_fetch_recurse_submodules_arg(var, value);
141                 return 0;
142         }
143         return 0;
144 }
145
146 void gitmodules_config(void)
147 {
148         const char *work_tree = get_git_work_tree();
149         if (work_tree) {
150                 struct strbuf gitmodules_path = STRBUF_INIT;
151                 int pos;
152                 strbuf_addstr(&gitmodules_path, work_tree);
153                 strbuf_addstr(&gitmodules_path, "/.gitmodules");
154                 if (read_cache() < 0)
155                         die("index file corrupt");
156                 pos = cache_name_pos(".gitmodules", 11);
157                 if (pos < 0) { /* .gitmodules not found or isn't merged */
158                         pos = -1 - pos;
159                         if (active_nr > pos) {  /* there is a .gitmodules */
160                                 const struct cache_entry *ce = active_cache[pos];
161                                 if (ce_namelen(ce) == 11 &&
162                                     !memcmp(ce->name, ".gitmodules", 11))
163                                         gitmodules_is_unmerged = 1;
164                         }
165                 } else if (pos < active_nr) {
166                         struct stat st;
167                         if (lstat(".gitmodules", &st) == 0 &&
168                             ce_match_stat(active_cache[pos], &st, 0) & DATA_CHANGED)
169                                 gitmodules_is_modified = 1;
170                 }
171
172                 if (!gitmodules_is_unmerged)
173                         git_config_from_file(submodule_config, gitmodules_path.buf, NULL);
174                 strbuf_release(&gitmodules_path);
175         }
176 }
177
178 int parse_submodule_config_option(const char *var, const char *value)
179 {
180         struct string_list_item *config;
181         const char *name, *key;
182         int namelen;
183
184         if (parse_config_key(var, "submodule", &name, &namelen, &key) < 0 || !name)
185                 return 0;
186
187         if (!strcmp(key, "path")) {
188                 config = unsorted_string_list_lookup(&config_name_for_path, value);
189                 if (config)
190                         free(config->util);
191                 else
192                         config = string_list_append(&config_name_for_path, xstrdup(value));
193                 config->util = xmemdupz(name, namelen);
194         } else if (!strcmp(key, "fetchrecursesubmodules")) {
195                 char *name_cstr = xmemdupz(name, namelen);
196                 config = unsorted_string_list_lookup(&config_fetch_recurse_submodules_for_name, name_cstr);
197                 if (!config)
198                         config = string_list_append(&config_fetch_recurse_submodules_for_name, name_cstr);
199                 else
200                         free(name_cstr);
201                 config->util = (void *)(intptr_t)parse_fetch_recurse_submodules_arg(var, value);
202         } else if (!strcmp(key, "ignore")) {
203                 char *name_cstr;
204
205                 if (strcmp(value, "untracked") && strcmp(value, "dirty") &&
206                     strcmp(value, "all") && strcmp(value, "none")) {
207                         warning("Invalid parameter \"%s\" for config option \"submodule.%s.ignore\"", value, var);
208                         return 0;
209                 }
210
211                 name_cstr = xmemdupz(name, namelen);
212                 config = unsorted_string_list_lookup(&config_ignore_for_name, name_cstr);
213                 if (config) {
214                         free(config->util);
215                         free(name_cstr);
216                 } else
217                         config = string_list_append(&config_ignore_for_name, name_cstr);
218                 config->util = xstrdup(value);
219                 return 0;
220         }
221         return 0;
222 }
223
224 void handle_ignore_submodules_arg(struct diff_options *diffopt,
225                                   const char *arg)
226 {
227         DIFF_OPT_CLR(diffopt, IGNORE_SUBMODULES);
228         DIFF_OPT_CLR(diffopt, IGNORE_UNTRACKED_IN_SUBMODULES);
229         DIFF_OPT_CLR(diffopt, IGNORE_DIRTY_SUBMODULES);
230
231         if (!strcmp(arg, "all"))
232                 DIFF_OPT_SET(diffopt, IGNORE_SUBMODULES);
233         else if (!strcmp(arg, "untracked"))
234                 DIFF_OPT_SET(diffopt, IGNORE_UNTRACKED_IN_SUBMODULES);
235         else if (!strcmp(arg, "dirty"))
236                 DIFF_OPT_SET(diffopt, IGNORE_DIRTY_SUBMODULES);
237         else if (strcmp(arg, "none"))
238                 die("bad --ignore-submodules argument: %s", arg);
239 }
240
241 static int prepare_submodule_summary(struct rev_info *rev, const char *path,
242                 struct commit *left, struct commit *right,
243                 int *fast_forward, int *fast_backward)
244 {
245         struct commit_list *merge_bases, *list;
246
247         init_revisions(rev, NULL);
248         setup_revisions(0, NULL, rev, NULL);
249         rev->left_right = 1;
250         rev->first_parent_only = 1;
251         left->object.flags |= SYMMETRIC_LEFT;
252         add_pending_object(rev, &left->object, path);
253         add_pending_object(rev, &right->object, path);
254         merge_bases = get_merge_bases(left, right, 1);
255         if (merge_bases) {
256                 if (merge_bases->item == left)
257                         *fast_forward = 1;
258                 else if (merge_bases->item == right)
259                         *fast_backward = 1;
260         }
261         for (list = merge_bases; list; list = list->next) {
262                 list->item->object.flags |= UNINTERESTING;
263                 add_pending_object(rev, &list->item->object,
264                         sha1_to_hex(list->item->object.sha1));
265         }
266         return prepare_revision_walk(rev);
267 }
268
269 static void print_submodule_summary(struct rev_info *rev, FILE *f,
270                 const char *line_prefix,
271                 const char *del, const char *add, const char *reset)
272 {
273         static const char format[] = "  %m %s";
274         struct strbuf sb = STRBUF_INIT;
275         struct commit *commit;
276
277         while ((commit = get_revision(rev))) {
278                 struct pretty_print_context ctx = {0};
279                 ctx.date_mode = rev->date_mode;
280                 ctx.output_encoding = get_log_output_encoding();
281                 strbuf_setlen(&sb, 0);
282                 strbuf_addstr(&sb, line_prefix);
283                 if (commit->object.flags & SYMMETRIC_LEFT) {
284                         if (del)
285                                 strbuf_addstr(&sb, del);
286                 }
287                 else if (add)
288                         strbuf_addstr(&sb, add);
289                 format_commit_message(commit, format, &sb, &ctx);
290                 if (reset)
291                         strbuf_addstr(&sb, reset);
292                 strbuf_addch(&sb, '\n');
293                 fprintf(f, "%s", sb.buf);
294         }
295         strbuf_release(&sb);
296 }
297
298 int parse_fetch_recurse_submodules_arg(const char *opt, const char *arg)
299 {
300         switch (git_config_maybe_bool(opt, arg)) {
301         case 1:
302                 return RECURSE_SUBMODULES_ON;
303         case 0:
304                 return RECURSE_SUBMODULES_OFF;
305         default:
306                 if (!strcmp(arg, "on-demand"))
307                         return RECURSE_SUBMODULES_ON_DEMAND;
308                 die("bad %s argument: %s", opt, arg);
309         }
310 }
311
312 void show_submodule_summary(FILE *f, const char *path,
313                 const char *line_prefix,
314                 unsigned char one[20], unsigned char two[20],
315                 unsigned dirty_submodule, const char *meta,
316                 const char *del, const char *add, const char *reset)
317 {
318         struct rev_info rev;
319         struct commit *left = NULL, *right = NULL;
320         const char *message = NULL;
321         struct strbuf sb = STRBUF_INIT;
322         int fast_forward = 0, fast_backward = 0;
323
324         if (is_null_sha1(two))
325                 message = "(submodule deleted)";
326         else if (add_submodule_odb(path))
327                 message = "(not checked out)";
328         else if (is_null_sha1(one))
329                 message = "(new submodule)";
330         else if (!(left = lookup_commit_reference(one)) ||
331                  !(right = lookup_commit_reference(two)))
332                 message = "(commits not present)";
333         else if (prepare_submodule_summary(&rev, path, left, right,
334                                            &fast_forward, &fast_backward))
335                 message = "(revision walker failed)";
336
337         if (dirty_submodule & DIRTY_SUBMODULE_UNTRACKED)
338                 fprintf(f, "%sSubmodule %s contains untracked content\n",
339                         line_prefix, path);
340         if (dirty_submodule & DIRTY_SUBMODULE_MODIFIED)
341                 fprintf(f, "%sSubmodule %s contains modified content\n",
342                         line_prefix, path);
343
344         if (!hashcmp(one, two)) {
345                 strbuf_release(&sb);
346                 return;
347         }
348
349         strbuf_addf(&sb, "%s%sSubmodule %s %s..", line_prefix, meta, path,
350                         find_unique_abbrev(one, DEFAULT_ABBREV));
351         if (!fast_backward && !fast_forward)
352                 strbuf_addch(&sb, '.');
353         strbuf_addf(&sb, "%s", find_unique_abbrev(two, DEFAULT_ABBREV));
354         if (message)
355                 strbuf_addf(&sb, " %s%s\n", message, reset);
356         else
357                 strbuf_addf(&sb, "%s:%s\n", fast_backward ? " (rewind)" : "", reset);
358         fwrite(sb.buf, sb.len, 1, f);
359
360         if (!message) /* only NULL if we succeeded in setting up the walk */
361                 print_submodule_summary(&rev, f, line_prefix, del, add, reset);
362         if (left)
363                 clear_commit_marks(left, ~0);
364         if (right)
365                 clear_commit_marks(right, ~0);
366
367         strbuf_release(&sb);
368 }
369
370 void set_config_fetch_recurse_submodules(int value)
371 {
372         config_fetch_recurse_submodules = value;
373 }
374
375 static int has_remote(const char *refname, const unsigned char *sha1, int flags, void *cb_data)
376 {
377         return 1;
378 }
379
380 static int submodule_needs_pushing(const char *path, const unsigned char sha1[20])
381 {
382         if (add_submodule_odb(path) || !lookup_commit_reference(sha1))
383                 return 0;
384
385         if (for_each_remote_ref_submodule(path, has_remote, NULL) > 0) {
386                 struct child_process cp;
387                 const char *argv[] = {"rev-list", NULL, "--not", "--remotes", "-n", "1" , NULL};
388                 struct strbuf buf = STRBUF_INIT;
389                 int needs_pushing = 0;
390
391                 argv[1] = sha1_to_hex(sha1);
392                 memset(&cp, 0, sizeof(cp));
393                 cp.argv = argv;
394                 cp.env = local_repo_env;
395                 cp.git_cmd = 1;
396                 cp.no_stdin = 1;
397                 cp.out = -1;
398                 cp.dir = path;
399                 if (start_command(&cp))
400                         die("Could not run 'git rev-list %s --not --remotes -n 1' command in submodule %s",
401                                 sha1_to_hex(sha1), path);
402                 if (strbuf_read(&buf, cp.out, 41))
403                         needs_pushing = 1;
404                 finish_command(&cp);
405                 close(cp.out);
406                 strbuf_release(&buf);
407                 return needs_pushing;
408         }
409
410         return 0;
411 }
412
413 static void collect_submodules_from_diff(struct diff_queue_struct *q,
414                                          struct diff_options *options,
415                                          void *data)
416 {
417         int i;
418         struct string_list *needs_pushing = data;
419
420         for (i = 0; i < q->nr; i++) {
421                 struct diff_filepair *p = q->queue[i];
422                 if (!S_ISGITLINK(p->two->mode))
423                         continue;
424                 if (submodule_needs_pushing(p->two->path, p->two->sha1))
425                         string_list_insert(needs_pushing, p->two->path);
426         }
427 }
428
429 static void find_unpushed_submodule_commits(struct commit *commit,
430                 struct string_list *needs_pushing)
431 {
432         struct rev_info rev;
433
434         init_revisions(&rev, NULL);
435         rev.diffopt.output_format |= DIFF_FORMAT_CALLBACK;
436         rev.diffopt.format_callback = collect_submodules_from_diff;
437         rev.diffopt.format_callback_data = needs_pushing;
438         diff_tree_combined_merge(commit, 1, &rev);
439 }
440
441 int find_unpushed_submodules(unsigned char new_sha1[20],
442                 const char *remotes_name, struct string_list *needs_pushing)
443 {
444         struct rev_info rev;
445         struct commit *commit;
446         const char *argv[] = {NULL, NULL, "--not", "NULL", NULL};
447         int argc = ARRAY_SIZE(argv) - 1;
448         char *sha1_copy;
449
450         struct strbuf remotes_arg = STRBUF_INIT;
451
452         strbuf_addf(&remotes_arg, "--remotes=%s", remotes_name);
453         init_revisions(&rev, NULL);
454         sha1_copy = xstrdup(sha1_to_hex(new_sha1));
455         argv[1] = sha1_copy;
456         argv[3] = remotes_arg.buf;
457         setup_revisions(argc, argv, &rev, NULL);
458         if (prepare_revision_walk(&rev))
459                 die("revision walk setup failed");
460
461         while ((commit = get_revision(&rev)) != NULL)
462                 find_unpushed_submodule_commits(commit, needs_pushing);
463
464         reset_revision_walk();
465         free(sha1_copy);
466         strbuf_release(&remotes_arg);
467
468         return needs_pushing->nr;
469 }
470
471 static int push_submodule(const char *path)
472 {
473         if (add_submodule_odb(path))
474                 return 1;
475
476         if (for_each_remote_ref_submodule(path, has_remote, NULL) > 0) {
477                 struct child_process cp;
478                 const char *argv[] = {"push", NULL};
479
480                 memset(&cp, 0, sizeof(cp));
481                 cp.argv = argv;
482                 cp.env = local_repo_env;
483                 cp.git_cmd = 1;
484                 cp.no_stdin = 1;
485                 cp.dir = path;
486                 if (run_command(&cp))
487                         return 0;
488                 close(cp.out);
489         }
490
491         return 1;
492 }
493
494 int push_unpushed_submodules(unsigned char new_sha1[20], const char *remotes_name)
495 {
496         int i, ret = 1;
497         struct string_list needs_pushing;
498
499         memset(&needs_pushing, 0, sizeof(struct string_list));
500         needs_pushing.strdup_strings = 1;
501
502         if (!find_unpushed_submodules(new_sha1, remotes_name, &needs_pushing))
503                 return 1;
504
505         for (i = 0; i < needs_pushing.nr; i++) {
506                 const char *path = needs_pushing.items[i].string;
507                 fprintf(stderr, "Pushing submodule '%s'\n", path);
508                 if (!push_submodule(path)) {
509                         fprintf(stderr, "Unable to push submodule '%s'\n", path);
510                         ret = 0;
511                 }
512         }
513
514         string_list_clear(&needs_pushing, 0);
515
516         return ret;
517 }
518
519 static int is_submodule_commit_present(const char *path, unsigned char sha1[20])
520 {
521         int is_present = 0;
522         if (!add_submodule_odb(path) && lookup_commit_reference(sha1)) {
523                 /* Even if the submodule is checked out and the commit is
524                  * present, make sure it is reachable from a ref. */
525                 struct child_process cp;
526                 const char *argv[] = {"rev-list", "-n", "1", NULL, "--not", "--all", NULL};
527                 struct strbuf buf = STRBUF_INIT;
528
529                 argv[3] = sha1_to_hex(sha1);
530                 memset(&cp, 0, sizeof(cp));
531                 cp.argv = argv;
532                 cp.env = local_repo_env;
533                 cp.git_cmd = 1;
534                 cp.no_stdin = 1;
535                 cp.out = -1;
536                 cp.dir = path;
537                 if (!run_command(&cp) && !strbuf_read(&buf, cp.out, 1024))
538                         is_present = 1;
539
540                 close(cp.out);
541                 strbuf_release(&buf);
542         }
543         return is_present;
544 }
545
546 static void submodule_collect_changed_cb(struct diff_queue_struct *q,
547                                          struct diff_options *options,
548                                          void *data)
549 {
550         int i;
551         for (i = 0; i < q->nr; i++) {
552                 struct diff_filepair *p = q->queue[i];
553                 if (!S_ISGITLINK(p->two->mode))
554                         continue;
555
556                 if (S_ISGITLINK(p->one->mode)) {
557                         /* NEEDSWORK: We should honor the name configured in
558                          * the .gitmodules file of the commit we are examining
559                          * here to be able to correctly follow submodules
560                          * being moved around. */
561                         struct string_list_item *path;
562                         path = unsorted_string_list_lookup(&changed_submodule_paths, p->two->path);
563                         if (!path && !is_submodule_commit_present(p->two->path, p->two->sha1))
564                                 string_list_append(&changed_submodule_paths, xstrdup(p->two->path));
565                 } else {
566                         /* Submodule is new or was moved here */
567                         /* NEEDSWORK: When the .git directories of submodules
568                          * live inside the superprojects .git directory some
569                          * day we should fetch new submodules directly into
570                          * that location too when config or options request
571                          * that so they can be checked out from there. */
572                         continue;
573                 }
574         }
575 }
576
577 static int add_sha1_to_array(const char *ref, const unsigned char *sha1,
578                              int flags, void *data)
579 {
580         sha1_array_append(data, sha1);
581         return 0;
582 }
583
584 void check_for_new_submodule_commits(unsigned char new_sha1[20])
585 {
586         if (!initialized_fetch_ref_tips) {
587                 for_each_ref(add_sha1_to_array, &ref_tips_before_fetch);
588                 initialized_fetch_ref_tips = 1;
589         }
590
591         sha1_array_append(&ref_tips_after_fetch, new_sha1);
592 }
593
594 static void add_sha1_to_argv(const unsigned char sha1[20], void *data)
595 {
596         argv_array_push(data, sha1_to_hex(sha1));
597 }
598
599 static void calculate_changed_submodule_paths(void)
600 {
601         struct rev_info rev;
602         struct commit *commit;
603         struct argv_array argv = ARGV_ARRAY_INIT;
604
605         /* No need to check if there are no submodules configured */
606         if (!config_name_for_path.nr)
607                 return;
608
609         init_revisions(&rev, NULL);
610         argv_array_push(&argv, "--"); /* argv[0] program name */
611         sha1_array_for_each_unique(&ref_tips_after_fetch,
612                                    add_sha1_to_argv, &argv);
613         argv_array_push(&argv, "--not");
614         sha1_array_for_each_unique(&ref_tips_before_fetch,
615                                    add_sha1_to_argv, &argv);
616         setup_revisions(argv.argc, argv.argv, &rev, NULL);
617         if (prepare_revision_walk(&rev))
618                 die("revision walk setup failed");
619
620         /*
621          * Collect all submodules (whether checked out or not) for which new
622          * commits have been recorded upstream in "changed_submodule_paths".
623          */
624         while ((commit = get_revision(&rev))) {
625                 struct commit_list *parent = commit->parents;
626                 while (parent) {
627                         struct diff_options diff_opts;
628                         diff_setup(&diff_opts);
629                         DIFF_OPT_SET(&diff_opts, RECURSIVE);
630                         diff_opts.output_format |= DIFF_FORMAT_CALLBACK;
631                         diff_opts.format_callback = submodule_collect_changed_cb;
632                         diff_setup_done(&diff_opts);
633                         diff_tree_sha1(parent->item->object.sha1, commit->object.sha1, "", &diff_opts);
634                         diffcore_std(&diff_opts);
635                         diff_flush(&diff_opts);
636                         parent = parent->next;
637                 }
638         }
639
640         argv_array_clear(&argv);
641         sha1_array_clear(&ref_tips_before_fetch);
642         sha1_array_clear(&ref_tips_after_fetch);
643         initialized_fetch_ref_tips = 0;
644 }
645
646 int fetch_populated_submodules(const struct argv_array *options,
647                                const char *prefix, int command_line_option,
648                                int quiet)
649 {
650         int i, result = 0;
651         struct child_process cp;
652         struct argv_array argv = ARGV_ARRAY_INIT;
653         struct string_list_item *name_for_path;
654         const char *work_tree = get_git_work_tree();
655         if (!work_tree)
656                 goto out;
657
658         if (read_cache() < 0)
659                 die("index file corrupt");
660
661         argv_array_push(&argv, "fetch");
662         for (i = 0; i < options->argc; i++)
663                 argv_array_push(&argv, options->argv[i]);
664         argv_array_push(&argv, "--recurse-submodules-default");
665         /* default value, "--submodule-prefix" and its value are added later */
666
667         memset(&cp, 0, sizeof(cp));
668         cp.env = local_repo_env;
669         cp.git_cmd = 1;
670         cp.no_stdin = 1;
671
672         calculate_changed_submodule_paths();
673
674         for (i = 0; i < active_nr; i++) {
675                 struct strbuf submodule_path = STRBUF_INIT;
676                 struct strbuf submodule_git_dir = STRBUF_INIT;
677                 struct strbuf submodule_prefix = STRBUF_INIT;
678                 struct cache_entry *ce = active_cache[i];
679                 const char *git_dir, *name, *default_argv;
680
681                 if (!S_ISGITLINK(ce->ce_mode))
682                         continue;
683
684                 name = ce->name;
685                 name_for_path = unsorted_string_list_lookup(&config_name_for_path, ce->name);
686                 if (name_for_path)
687                         name = name_for_path->util;
688
689                 default_argv = "yes";
690                 if (command_line_option == RECURSE_SUBMODULES_DEFAULT) {
691                         struct string_list_item *fetch_recurse_submodules_option;
692                         fetch_recurse_submodules_option = unsorted_string_list_lookup(&config_fetch_recurse_submodules_for_name, name);
693                         if (fetch_recurse_submodules_option) {
694                                 if ((intptr_t)fetch_recurse_submodules_option->util == RECURSE_SUBMODULES_OFF)
695                                         continue;
696                                 if ((intptr_t)fetch_recurse_submodules_option->util == RECURSE_SUBMODULES_ON_DEMAND) {
697                                         if (!unsorted_string_list_lookup(&changed_submodule_paths, ce->name))
698                                                 continue;
699                                         default_argv = "on-demand";
700                                 }
701                         } else {
702                                 if ((config_fetch_recurse_submodules == RECURSE_SUBMODULES_OFF) ||
703                                     gitmodules_is_unmerged)
704                                         continue;
705                                 if (config_fetch_recurse_submodules == RECURSE_SUBMODULES_ON_DEMAND) {
706                                         if (!unsorted_string_list_lookup(&changed_submodule_paths, ce->name))
707                                                 continue;
708                                         default_argv = "on-demand";
709                                 }
710                         }
711                 } else if (command_line_option == RECURSE_SUBMODULES_ON_DEMAND) {
712                         if (!unsorted_string_list_lookup(&changed_submodule_paths, ce->name))
713                                 continue;
714                         default_argv = "on-demand";
715                 }
716
717                 strbuf_addf(&submodule_path, "%s/%s", work_tree, ce->name);
718                 strbuf_addf(&submodule_git_dir, "%s/.git", submodule_path.buf);
719                 strbuf_addf(&submodule_prefix, "%s%s/", prefix, ce->name);
720                 git_dir = read_gitfile(submodule_git_dir.buf);
721                 if (!git_dir)
722                         git_dir = submodule_git_dir.buf;
723                 if (is_directory(git_dir)) {
724                         if (!quiet)
725                                 printf("Fetching submodule %s%s\n", prefix, ce->name);
726                         cp.dir = submodule_path.buf;
727                         argv_array_push(&argv, default_argv);
728                         argv_array_push(&argv, "--submodule-prefix");
729                         argv_array_push(&argv, submodule_prefix.buf);
730                         cp.argv = argv.argv;
731                         if (run_command(&cp))
732                                 result = 1;
733                         argv_array_pop(&argv);
734                         argv_array_pop(&argv);
735                         argv_array_pop(&argv);
736                 }
737                 strbuf_release(&submodule_path);
738                 strbuf_release(&submodule_git_dir);
739                 strbuf_release(&submodule_prefix);
740         }
741         argv_array_clear(&argv);
742 out:
743         string_list_clear(&changed_submodule_paths, 1);
744         return result;
745 }
746
747 unsigned is_submodule_modified(const char *path, int ignore_untracked)
748 {
749         ssize_t len;
750         struct child_process cp;
751         const char *argv[] = {
752                 "status",
753                 "--porcelain",
754                 NULL,
755                 NULL,
756         };
757         struct strbuf buf = STRBUF_INIT;
758         unsigned dirty_submodule = 0;
759         const char *line, *next_line;
760         const char *git_dir;
761
762         strbuf_addf(&buf, "%s/.git", path);
763         git_dir = read_gitfile(buf.buf);
764         if (!git_dir)
765                 git_dir = buf.buf;
766         if (!is_directory(git_dir)) {
767                 strbuf_release(&buf);
768                 /* The submodule is not checked out, so it is not modified */
769                 return 0;
770
771         }
772         strbuf_reset(&buf);
773
774         if (ignore_untracked)
775                 argv[2] = "-uno";
776
777         memset(&cp, 0, sizeof(cp));
778         cp.argv = argv;
779         cp.env = local_repo_env;
780         cp.git_cmd = 1;
781         cp.no_stdin = 1;
782         cp.out = -1;
783         cp.dir = path;
784         if (start_command(&cp))
785                 die("Could not run 'git status --porcelain' in submodule %s", path);
786
787         len = strbuf_read(&buf, cp.out, 1024);
788         line = buf.buf;
789         while (len > 2) {
790                 if ((line[0] == '?') && (line[1] == '?')) {
791                         dirty_submodule |= DIRTY_SUBMODULE_UNTRACKED;
792                         if (dirty_submodule & DIRTY_SUBMODULE_MODIFIED)
793                                 break;
794                 } else {
795                         dirty_submodule |= DIRTY_SUBMODULE_MODIFIED;
796                         if (ignore_untracked ||
797                             (dirty_submodule & DIRTY_SUBMODULE_UNTRACKED))
798                                 break;
799                 }
800                 next_line = strchr(line, '\n');
801                 if (!next_line)
802                         break;
803                 next_line++;
804                 len -= (next_line - line);
805                 line = next_line;
806         }
807         close(cp.out);
808
809         if (finish_command(&cp))
810                 die("'git status --porcelain' failed in submodule %s", path);
811
812         strbuf_release(&buf);
813         return dirty_submodule;
814 }
815
816 int submodule_uses_gitfile(const char *path)
817 {
818         struct child_process cp;
819         const char *argv[] = {
820                 "submodule",
821                 "foreach",
822                 "--quiet",
823                 "--recursive",
824                 "test -f .git",
825                 NULL,
826         };
827         struct strbuf buf = STRBUF_INIT;
828         const char *git_dir;
829
830         strbuf_addf(&buf, "%s/.git", path);
831         git_dir = read_gitfile(buf.buf);
832         if (!git_dir) {
833                 strbuf_release(&buf);
834                 return 0;
835         }
836         strbuf_release(&buf);
837
838         /* Now test that all nested submodules use a gitfile too */
839         memset(&cp, 0, sizeof(cp));
840         cp.argv = argv;
841         cp.env = local_repo_env;
842         cp.git_cmd = 1;
843         cp.no_stdin = 1;
844         cp.no_stderr = 1;
845         cp.no_stdout = 1;
846         cp.dir = path;
847         if (run_command(&cp))
848                 return 0;
849
850         return 1;
851 }
852
853 int ok_to_remove_submodule(const char *path)
854 {
855         struct stat st;
856         ssize_t len;
857         struct child_process cp;
858         const char *argv[] = {
859                 "status",
860                 "--porcelain",
861                 "-u",
862                 "--ignore-submodules=none",
863                 NULL,
864         };
865         struct strbuf buf = STRBUF_INIT;
866         int ok_to_remove = 1;
867
868         if ((lstat(path, &st) < 0) || is_empty_dir(path))
869                 return 1;
870
871         if (!submodule_uses_gitfile(path))
872                 return 0;
873
874         memset(&cp, 0, sizeof(cp));
875         cp.argv = argv;
876         cp.env = local_repo_env;
877         cp.git_cmd = 1;
878         cp.no_stdin = 1;
879         cp.out = -1;
880         cp.dir = path;
881         if (start_command(&cp))
882                 die("Could not run 'git status --porcelain -uall --ignore-submodules=none' in submodule %s", path);
883
884         len = strbuf_read(&buf, cp.out, 1024);
885         if (len > 2)
886                 ok_to_remove = 0;
887         close(cp.out);
888
889         if (finish_command(&cp))
890                 die("'git status --porcelain -uall --ignore-submodules=none' failed in submodule %s", path);
891
892         strbuf_release(&buf);
893         return ok_to_remove;
894 }
895
896 static int find_first_merges(struct object_array *result, const char *path,
897                 struct commit *a, struct commit *b)
898 {
899         int i, j;
900         struct object_array merges = OBJECT_ARRAY_INIT;
901         struct commit *commit;
902         int contains_another;
903
904         char merged_revision[42];
905         const char *rev_args[] = { "rev-list", "--merges", "--ancestry-path",
906                                    "--all", merged_revision, NULL };
907         struct rev_info revs;
908         struct setup_revision_opt rev_opts;
909
910         memset(result, 0, sizeof(struct object_array));
911         memset(&rev_opts, 0, sizeof(rev_opts));
912
913         /* get all revisions that merge commit a */
914         snprintf(merged_revision, sizeof(merged_revision), "^%s",
915                         sha1_to_hex(a->object.sha1));
916         init_revisions(&revs, NULL);
917         rev_opts.submodule = path;
918         setup_revisions(sizeof(rev_args)/sizeof(char *)-1, rev_args, &revs, &rev_opts);
919
920         /* save all revisions from the above list that contain b */
921         if (prepare_revision_walk(&revs))
922                 die("revision walk setup failed");
923         while ((commit = get_revision(&revs)) != NULL) {
924                 struct object *o = &(commit->object);
925                 if (in_merge_bases(b, commit))
926                         add_object_array(o, NULL, &merges);
927         }
928         reset_revision_walk();
929
930         /* Now we've got all merges that contain a and b. Prune all
931          * merges that contain another found merge and save them in
932          * result.
933          */
934         for (i = 0; i < merges.nr; i++) {
935                 struct commit *m1 = (struct commit *) merges.objects[i].item;
936
937                 contains_another = 0;
938                 for (j = 0; j < merges.nr; j++) {
939                         struct commit *m2 = (struct commit *) merges.objects[j].item;
940                         if (i != j && in_merge_bases(m2, m1)) {
941                                 contains_another = 1;
942                                 break;
943                         }
944                 }
945
946                 if (!contains_another)
947                         add_object_array(merges.objects[i].item, NULL, result);
948         }
949
950         free(merges.objects);
951         return result->nr;
952 }
953
954 static void print_commit(struct commit *commit)
955 {
956         struct strbuf sb = STRBUF_INIT;
957         struct pretty_print_context ctx = {0};
958         ctx.date_mode = DATE_NORMAL;
959         format_commit_message(commit, " %h: %m %s", &sb, &ctx);
960         fprintf(stderr, "%s\n", sb.buf);
961         strbuf_release(&sb);
962 }
963
964 #define MERGE_WARNING(path, msg) \
965         warning("Failed to merge submodule %s (%s)", path, msg);
966
967 int merge_submodule(unsigned char result[20], const char *path,
968                     const unsigned char base[20], const unsigned char a[20],
969                     const unsigned char b[20], int search)
970 {
971         struct commit *commit_base, *commit_a, *commit_b;
972         int parent_count;
973         struct object_array merges;
974
975         int i;
976
977         /* store a in result in case we fail */
978         hashcpy(result, a);
979
980         /* we can not handle deletion conflicts */
981         if (is_null_sha1(base))
982                 return 0;
983         if (is_null_sha1(a))
984                 return 0;
985         if (is_null_sha1(b))
986                 return 0;
987
988         if (add_submodule_odb(path)) {
989                 MERGE_WARNING(path, "not checked out");
990                 return 0;
991         }
992
993         if (!(commit_base = lookup_commit_reference(base)) ||
994             !(commit_a = lookup_commit_reference(a)) ||
995             !(commit_b = lookup_commit_reference(b))) {
996                 MERGE_WARNING(path, "commits not present");
997                 return 0;
998         }
999
1000         /* check whether both changes are forward */
1001         if (!in_merge_bases(commit_base, commit_a) ||
1002             !in_merge_bases(commit_base, commit_b)) {
1003                 MERGE_WARNING(path, "commits don't follow merge-base");
1004                 return 0;
1005         }
1006
1007         /* Case #1: a is contained in b or vice versa */
1008         if (in_merge_bases(commit_a, commit_b)) {
1009                 hashcpy(result, b);
1010                 return 1;
1011         }
1012         if (in_merge_bases(commit_b, commit_a)) {
1013                 hashcpy(result, a);
1014                 return 1;
1015         }
1016
1017         /*
1018          * Case #2: There are one or more merges that contain a and b in
1019          * the submodule. If there is only one, then present it as a
1020          * suggestion to the user, but leave it marked unmerged so the
1021          * user needs to confirm the resolution.
1022          */
1023
1024         /* Skip the search if makes no sense to the calling context.  */
1025         if (!search)
1026                 return 0;
1027
1028         /* find commit which merges them */
1029         parent_count = find_first_merges(&merges, path, commit_a, commit_b);
1030         switch (parent_count) {
1031         case 0:
1032                 MERGE_WARNING(path, "merge following commits not found");
1033                 break;
1034
1035         case 1:
1036                 MERGE_WARNING(path, "not fast-forward");
1037                 fprintf(stderr, "Found a possible merge resolution "
1038                                 "for the submodule:\n");
1039                 print_commit((struct commit *) merges.objects[0].item);
1040                 fprintf(stderr,
1041                         "If this is correct simply add it to the index "
1042                         "for example\n"
1043                         "by using:\n\n"
1044                         "  git update-index --cacheinfo 160000 %s \"%s\"\n\n"
1045                         "which will accept this suggestion.\n",
1046                         sha1_to_hex(merges.objects[0].item->sha1), path);
1047                 break;
1048
1049         default:
1050                 MERGE_WARNING(path, "multiple merges found");
1051                 for (i = 0; i < merges.nr; i++)
1052                         print_commit((struct commit *) merges.objects[i].item);
1053         }
1054
1055         free(merges.objects);
1056         return 0;
1057 }
1058
1059 /* Update gitfile and core.worktree setting to connect work tree and git dir */
1060 void connect_work_tree_and_git_dir(const char *work_tree, const char *git_dir)
1061 {
1062         struct strbuf file_name = STRBUF_INIT;
1063         struct strbuf rel_path = STRBUF_INIT;
1064         const char *real_work_tree = xstrdup(real_path(work_tree));
1065         FILE *fp;
1066
1067         /* Update gitfile */
1068         strbuf_addf(&file_name, "%s/.git", work_tree);
1069         fp = fopen(file_name.buf, "w");
1070         if (!fp)
1071                 die(_("Could not create git link %s"), file_name.buf);
1072         fprintf(fp, "gitdir: %s\n", relative_path(git_dir, real_work_tree,
1073                                                   &rel_path));
1074         fclose(fp);
1075
1076         /* Update core.worktree setting */
1077         strbuf_reset(&file_name);
1078         strbuf_addf(&file_name, "%s/config", git_dir);
1079         if (git_config_set_in_file(file_name.buf, "core.worktree",
1080                                    relative_path(real_work_tree, git_dir,
1081                                                  &rel_path)))
1082                 die(_("Could not set core.worktree in %s"),
1083                     file_name.buf);
1084
1085         strbuf_release(&file_name);
1086         strbuf_release(&rel_path);
1087         free((void *)real_work_tree);
1088 }