mv: update the path entry in .gitmodules for moved submodules
[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 /*
51  * Try to update the "path" entry in the "submodule.<name>" section of the
52  * .gitmodules file. Return 0 only if a .gitmodules file was found, a section
53  * with the correct path=<oldpath> setting was found and we could update it.
54  */
55 int update_path_in_gitmodules(const char *oldpath, const char *newpath)
56 {
57         struct strbuf entry = STRBUF_INIT;
58         struct string_list_item *path_option;
59
60         if (!file_exists(".gitmodules")) /* Do nothing without .gitmodules */
61                 return -1;
62
63         if (gitmodules_is_unmerged)
64                 die(_("Cannot change unmerged .gitmodules, resolve merge conflicts first"));
65
66         path_option = unsorted_string_list_lookup(&config_name_for_path, oldpath);
67         if (!path_option) {
68                 warning(_("Could not find section in .gitmodules where path=%s"), oldpath);
69                 return -1;
70         }
71         strbuf_addstr(&entry, "submodule.");
72         strbuf_addstr(&entry, path_option->util);
73         strbuf_addstr(&entry, ".path");
74         if (git_config_set_in_file(".gitmodules", entry.buf, newpath) < 0) {
75                 /* Maybe the user already did that, don't error out here */
76                 warning(_("Could not update .gitmodules entry %s"), entry.buf);
77                 strbuf_release(&entry);
78                 return -1;
79         }
80         strbuf_release(&entry);
81         return 0;
82 }
83
84 void stage_updated_gitmodules(void)
85 {
86         struct strbuf buf = STRBUF_INIT;
87         struct stat st;
88         int pos;
89         struct cache_entry *ce;
90         int namelen = strlen(".gitmodules");
91
92         pos = cache_name_pos(".gitmodules", namelen);
93         if (pos < 0) {
94                 warning(_("could not find .gitmodules in index"));
95                 return;
96         }
97         ce = active_cache[pos];
98         ce->ce_flags = namelen;
99         if (strbuf_read_file(&buf, ".gitmodules", 0) < 0)
100                 die(_("reading updated .gitmodules failed"));
101         if (lstat(".gitmodules", &st) < 0)
102                 die_errno(_("unable to stat updated .gitmodules"));
103         fill_stat_cache_info(ce, &st);
104         ce->ce_mode = ce_mode_from_stat(ce, st.st_mode);
105         if (remove_cache_entry_at(pos) < 0)
106                 die(_("unable to remove .gitmodules from index"));
107         if (write_sha1_file(buf.buf, buf.len, blob_type, ce->sha1))
108                 die(_("adding updated .gitmodules failed"));
109         if (add_cache_entry(ce, ADD_CACHE_OK_TO_ADD|ADD_CACHE_OK_TO_REPLACE))
110                 die(_("staging updated .gitmodules failed"));
111 }
112
113 static int add_submodule_odb(const char *path)
114 {
115         struct strbuf objects_directory = STRBUF_INIT;
116         struct alternate_object_database *alt_odb;
117         int ret = 0;
118         const char *git_dir;
119
120         strbuf_addf(&objects_directory, "%s/.git", path);
121         git_dir = read_gitfile(objects_directory.buf);
122         if (git_dir) {
123                 strbuf_reset(&objects_directory);
124                 strbuf_addstr(&objects_directory, git_dir);
125         }
126         strbuf_addstr(&objects_directory, "/objects/");
127         if (!is_directory(objects_directory.buf)) {
128                 ret = -1;
129                 goto done;
130         }
131         /* avoid adding it twice */
132         for (alt_odb = alt_odb_list; alt_odb; alt_odb = alt_odb->next)
133                 if (alt_odb->name - alt_odb->base == objects_directory.len &&
134                                 !strncmp(alt_odb->base, objects_directory.buf,
135                                         objects_directory.len))
136                         goto done;
137
138         alt_odb = xmalloc(objects_directory.len + 42 + sizeof(*alt_odb));
139         alt_odb->next = alt_odb_list;
140         strcpy(alt_odb->base, objects_directory.buf);
141         alt_odb->name = alt_odb->base + objects_directory.len;
142         alt_odb->name[2] = '/';
143         alt_odb->name[40] = '\0';
144         alt_odb->name[41] = '\0';
145         alt_odb_list = alt_odb;
146
147         /* add possible alternates from the submodule */
148         read_info_alternates(objects_directory.buf, 0);
149         prepare_alt_odb();
150 done:
151         strbuf_release(&objects_directory);
152         return ret;
153 }
154
155 void set_diffopt_flags_from_submodule_config(struct diff_options *diffopt,
156                                              const char *path)
157 {
158         struct string_list_item *path_option, *ignore_option;
159         path_option = unsorted_string_list_lookup(&config_name_for_path, path);
160         if (path_option) {
161                 ignore_option = unsorted_string_list_lookup(&config_ignore_for_name, path_option->util);
162                 if (ignore_option)
163                         handle_ignore_submodules_arg(diffopt, ignore_option->util);
164                 else if (gitmodules_is_unmerged)
165                         DIFF_OPT_SET(diffopt, IGNORE_SUBMODULES);
166         }
167 }
168
169 int submodule_config(const char *var, const char *value, void *cb)
170 {
171         if (!prefixcmp(var, "submodule."))
172                 return parse_submodule_config_option(var, value);
173         else if (!strcmp(var, "fetch.recursesubmodules")) {
174                 config_fetch_recurse_submodules = parse_fetch_recurse_submodules_arg(var, value);
175                 return 0;
176         }
177         return 0;
178 }
179
180 void gitmodules_config(void)
181 {
182         const char *work_tree = get_git_work_tree();
183         if (work_tree) {
184                 struct strbuf gitmodules_path = STRBUF_INIT;
185                 int pos;
186                 strbuf_addstr(&gitmodules_path, work_tree);
187                 strbuf_addstr(&gitmodules_path, "/.gitmodules");
188                 if (read_cache() < 0)
189                         die("index file corrupt");
190                 pos = cache_name_pos(".gitmodules", 11);
191                 if (pos < 0) { /* .gitmodules not found or isn't merged */
192                         pos = -1 - pos;
193                         if (active_nr > pos) {  /* there is a .gitmodules */
194                                 const struct cache_entry *ce = active_cache[pos];
195                                 if (ce_namelen(ce) == 11 &&
196                                     !memcmp(ce->name, ".gitmodules", 11))
197                                         gitmodules_is_unmerged = 1;
198                         }
199                 } else if (pos < active_nr) {
200                         struct stat st;
201                         if (lstat(".gitmodules", &st) == 0 &&
202                             ce_match_stat(active_cache[pos], &st, 0) & DATA_CHANGED)
203                                 gitmodules_is_modified = 1;
204                 }
205
206                 if (!gitmodules_is_unmerged)
207                         git_config_from_file(submodule_config, gitmodules_path.buf, NULL);
208                 strbuf_release(&gitmodules_path);
209         }
210 }
211
212 int parse_submodule_config_option(const char *var, const char *value)
213 {
214         struct string_list_item *config;
215         const char *name, *key;
216         int namelen;
217
218         if (parse_config_key(var, "submodule", &name, &namelen, &key) < 0 || !name)
219                 return 0;
220
221         if (!strcmp(key, "path")) {
222                 config = unsorted_string_list_lookup(&config_name_for_path, value);
223                 if (config)
224                         free(config->util);
225                 else
226                         config = string_list_append(&config_name_for_path, xstrdup(value));
227                 config->util = xmemdupz(name, namelen);
228         } else if (!strcmp(key, "fetchrecursesubmodules")) {
229                 char *name_cstr = xmemdupz(name, namelen);
230                 config = unsorted_string_list_lookup(&config_fetch_recurse_submodules_for_name, name_cstr);
231                 if (!config)
232                         config = string_list_append(&config_fetch_recurse_submodules_for_name, name_cstr);
233                 else
234                         free(name_cstr);
235                 config->util = (void *)(intptr_t)parse_fetch_recurse_submodules_arg(var, value);
236         } else if (!strcmp(key, "ignore")) {
237                 char *name_cstr;
238
239                 if (strcmp(value, "untracked") && strcmp(value, "dirty") &&
240                     strcmp(value, "all") && strcmp(value, "none")) {
241                         warning("Invalid parameter \"%s\" for config option \"submodule.%s.ignore\"", value, var);
242                         return 0;
243                 }
244
245                 name_cstr = xmemdupz(name, namelen);
246                 config = unsorted_string_list_lookup(&config_ignore_for_name, name_cstr);
247                 if (config) {
248                         free(config->util);
249                         free(name_cstr);
250                 } else
251                         config = string_list_append(&config_ignore_for_name, name_cstr);
252                 config->util = xstrdup(value);
253                 return 0;
254         }
255         return 0;
256 }
257
258 void handle_ignore_submodules_arg(struct diff_options *diffopt,
259                                   const char *arg)
260 {
261         DIFF_OPT_CLR(diffopt, IGNORE_SUBMODULES);
262         DIFF_OPT_CLR(diffopt, IGNORE_UNTRACKED_IN_SUBMODULES);
263         DIFF_OPT_CLR(diffopt, IGNORE_DIRTY_SUBMODULES);
264
265         if (!strcmp(arg, "all"))
266                 DIFF_OPT_SET(diffopt, IGNORE_SUBMODULES);
267         else if (!strcmp(arg, "untracked"))
268                 DIFF_OPT_SET(diffopt, IGNORE_UNTRACKED_IN_SUBMODULES);
269         else if (!strcmp(arg, "dirty"))
270                 DIFF_OPT_SET(diffopt, IGNORE_DIRTY_SUBMODULES);
271         else if (strcmp(arg, "none"))
272                 die("bad --ignore-submodules argument: %s", arg);
273 }
274
275 static int prepare_submodule_summary(struct rev_info *rev, const char *path,
276                 struct commit *left, struct commit *right,
277                 int *fast_forward, int *fast_backward)
278 {
279         struct commit_list *merge_bases, *list;
280
281         init_revisions(rev, NULL);
282         setup_revisions(0, NULL, rev, NULL);
283         rev->left_right = 1;
284         rev->first_parent_only = 1;
285         left->object.flags |= SYMMETRIC_LEFT;
286         add_pending_object(rev, &left->object, path);
287         add_pending_object(rev, &right->object, path);
288         merge_bases = get_merge_bases(left, right, 1);
289         if (merge_bases) {
290                 if (merge_bases->item == left)
291                         *fast_forward = 1;
292                 else if (merge_bases->item == right)
293                         *fast_backward = 1;
294         }
295         for (list = merge_bases; list; list = list->next) {
296                 list->item->object.flags |= UNINTERESTING;
297                 add_pending_object(rev, &list->item->object,
298                         sha1_to_hex(list->item->object.sha1));
299         }
300         return prepare_revision_walk(rev);
301 }
302
303 static void print_submodule_summary(struct rev_info *rev, FILE *f,
304                 const char *line_prefix,
305                 const char *del, const char *add, const char *reset)
306 {
307         static const char format[] = "  %m %s";
308         struct strbuf sb = STRBUF_INIT;
309         struct commit *commit;
310
311         while ((commit = get_revision(rev))) {
312                 struct pretty_print_context ctx = {0};
313                 ctx.date_mode = rev->date_mode;
314                 ctx.output_encoding = get_log_output_encoding();
315                 strbuf_setlen(&sb, 0);
316                 strbuf_addstr(&sb, line_prefix);
317                 if (commit->object.flags & SYMMETRIC_LEFT) {
318                         if (del)
319                                 strbuf_addstr(&sb, del);
320                 }
321                 else if (add)
322                         strbuf_addstr(&sb, add);
323                 format_commit_message(commit, format, &sb, &ctx);
324                 if (reset)
325                         strbuf_addstr(&sb, reset);
326                 strbuf_addch(&sb, '\n');
327                 fprintf(f, "%s", sb.buf);
328         }
329         strbuf_release(&sb);
330 }
331
332 int parse_fetch_recurse_submodules_arg(const char *opt, const char *arg)
333 {
334         switch (git_config_maybe_bool(opt, arg)) {
335         case 1:
336                 return RECURSE_SUBMODULES_ON;
337         case 0:
338                 return RECURSE_SUBMODULES_OFF;
339         default:
340                 if (!strcmp(arg, "on-demand"))
341                         return RECURSE_SUBMODULES_ON_DEMAND;
342                 die("bad %s argument: %s", opt, arg);
343         }
344 }
345
346 void show_submodule_summary(FILE *f, const char *path,
347                 const char *line_prefix,
348                 unsigned char one[20], unsigned char two[20],
349                 unsigned dirty_submodule, const char *meta,
350                 const char *del, const char *add, const char *reset)
351 {
352         struct rev_info rev;
353         struct commit *left = NULL, *right = NULL;
354         const char *message = NULL;
355         struct strbuf sb = STRBUF_INIT;
356         int fast_forward = 0, fast_backward = 0;
357
358         if (is_null_sha1(two))
359                 message = "(submodule deleted)";
360         else if (add_submodule_odb(path))
361                 message = "(not checked out)";
362         else if (is_null_sha1(one))
363                 message = "(new submodule)";
364         else if (!(left = lookup_commit_reference(one)) ||
365                  !(right = lookup_commit_reference(two)))
366                 message = "(commits not present)";
367         else if (prepare_submodule_summary(&rev, path, left, right,
368                                            &fast_forward, &fast_backward))
369                 message = "(revision walker failed)";
370
371         if (dirty_submodule & DIRTY_SUBMODULE_UNTRACKED)
372                 fprintf(f, "%sSubmodule %s contains untracked content\n",
373                         line_prefix, path);
374         if (dirty_submodule & DIRTY_SUBMODULE_MODIFIED)
375                 fprintf(f, "%sSubmodule %s contains modified content\n",
376                         line_prefix, path);
377
378         if (!hashcmp(one, two)) {
379                 strbuf_release(&sb);
380                 return;
381         }
382
383         strbuf_addf(&sb, "%s%sSubmodule %s %s..", line_prefix, meta, path,
384                         find_unique_abbrev(one, DEFAULT_ABBREV));
385         if (!fast_backward && !fast_forward)
386                 strbuf_addch(&sb, '.');
387         strbuf_addf(&sb, "%s", find_unique_abbrev(two, DEFAULT_ABBREV));
388         if (message)
389                 strbuf_addf(&sb, " %s%s\n", message, reset);
390         else
391                 strbuf_addf(&sb, "%s:%s\n", fast_backward ? " (rewind)" : "", reset);
392         fwrite(sb.buf, sb.len, 1, f);
393
394         if (!message) /* only NULL if we succeeded in setting up the walk */
395                 print_submodule_summary(&rev, f, line_prefix, del, add, reset);
396         if (left)
397                 clear_commit_marks(left, ~0);
398         if (right)
399                 clear_commit_marks(right, ~0);
400
401         strbuf_release(&sb);
402 }
403
404 void set_config_fetch_recurse_submodules(int value)
405 {
406         config_fetch_recurse_submodules = value;
407 }
408
409 static int has_remote(const char *refname, const unsigned char *sha1, int flags, void *cb_data)
410 {
411         return 1;
412 }
413
414 static int submodule_needs_pushing(const char *path, const unsigned char sha1[20])
415 {
416         if (add_submodule_odb(path) || !lookup_commit_reference(sha1))
417                 return 0;
418
419         if (for_each_remote_ref_submodule(path, has_remote, NULL) > 0) {
420                 struct child_process cp;
421                 const char *argv[] = {"rev-list", NULL, "--not", "--remotes", "-n", "1" , NULL};
422                 struct strbuf buf = STRBUF_INIT;
423                 int needs_pushing = 0;
424
425                 argv[1] = sha1_to_hex(sha1);
426                 memset(&cp, 0, sizeof(cp));
427                 cp.argv = argv;
428                 cp.env = local_repo_env;
429                 cp.git_cmd = 1;
430                 cp.no_stdin = 1;
431                 cp.out = -1;
432                 cp.dir = path;
433                 if (start_command(&cp))
434                         die("Could not run 'git rev-list %s --not --remotes -n 1' command in submodule %s",
435                                 sha1_to_hex(sha1), path);
436                 if (strbuf_read(&buf, cp.out, 41))
437                         needs_pushing = 1;
438                 finish_command(&cp);
439                 close(cp.out);
440                 strbuf_release(&buf);
441                 return needs_pushing;
442         }
443
444         return 0;
445 }
446
447 static void collect_submodules_from_diff(struct diff_queue_struct *q,
448                                          struct diff_options *options,
449                                          void *data)
450 {
451         int i;
452         struct string_list *needs_pushing = data;
453
454         for (i = 0; i < q->nr; i++) {
455                 struct diff_filepair *p = q->queue[i];
456                 if (!S_ISGITLINK(p->two->mode))
457                         continue;
458                 if (submodule_needs_pushing(p->two->path, p->two->sha1))
459                         string_list_insert(needs_pushing, p->two->path);
460         }
461 }
462
463 static void find_unpushed_submodule_commits(struct commit *commit,
464                 struct string_list *needs_pushing)
465 {
466         struct rev_info rev;
467
468         init_revisions(&rev, NULL);
469         rev.diffopt.output_format |= DIFF_FORMAT_CALLBACK;
470         rev.diffopt.format_callback = collect_submodules_from_diff;
471         rev.diffopt.format_callback_data = needs_pushing;
472         diff_tree_combined_merge(commit, 1, &rev);
473 }
474
475 int find_unpushed_submodules(unsigned char new_sha1[20],
476                 const char *remotes_name, struct string_list *needs_pushing)
477 {
478         struct rev_info rev;
479         struct commit *commit;
480         const char *argv[] = {NULL, NULL, "--not", "NULL", NULL};
481         int argc = ARRAY_SIZE(argv) - 1;
482         char *sha1_copy;
483
484         struct strbuf remotes_arg = STRBUF_INIT;
485
486         strbuf_addf(&remotes_arg, "--remotes=%s", remotes_name);
487         init_revisions(&rev, NULL);
488         sha1_copy = xstrdup(sha1_to_hex(new_sha1));
489         argv[1] = sha1_copy;
490         argv[3] = remotes_arg.buf;
491         setup_revisions(argc, argv, &rev, NULL);
492         if (prepare_revision_walk(&rev))
493                 die("revision walk setup failed");
494
495         while ((commit = get_revision(&rev)) != NULL)
496                 find_unpushed_submodule_commits(commit, needs_pushing);
497
498         reset_revision_walk();
499         free(sha1_copy);
500         strbuf_release(&remotes_arg);
501
502         return needs_pushing->nr;
503 }
504
505 static int push_submodule(const char *path)
506 {
507         if (add_submodule_odb(path))
508                 return 1;
509
510         if (for_each_remote_ref_submodule(path, has_remote, NULL) > 0) {
511                 struct child_process cp;
512                 const char *argv[] = {"push", NULL};
513
514                 memset(&cp, 0, sizeof(cp));
515                 cp.argv = argv;
516                 cp.env = local_repo_env;
517                 cp.git_cmd = 1;
518                 cp.no_stdin = 1;
519                 cp.dir = path;
520                 if (run_command(&cp))
521                         return 0;
522                 close(cp.out);
523         }
524
525         return 1;
526 }
527
528 int push_unpushed_submodules(unsigned char new_sha1[20], const char *remotes_name)
529 {
530         int i, ret = 1;
531         struct string_list needs_pushing;
532
533         memset(&needs_pushing, 0, sizeof(struct string_list));
534         needs_pushing.strdup_strings = 1;
535
536         if (!find_unpushed_submodules(new_sha1, remotes_name, &needs_pushing))
537                 return 1;
538
539         for (i = 0; i < needs_pushing.nr; i++) {
540                 const char *path = needs_pushing.items[i].string;
541                 fprintf(stderr, "Pushing submodule '%s'\n", path);
542                 if (!push_submodule(path)) {
543                         fprintf(stderr, "Unable to push submodule '%s'\n", path);
544                         ret = 0;
545                 }
546         }
547
548         string_list_clear(&needs_pushing, 0);
549
550         return ret;
551 }
552
553 static int is_submodule_commit_present(const char *path, unsigned char sha1[20])
554 {
555         int is_present = 0;
556         if (!add_submodule_odb(path) && lookup_commit_reference(sha1)) {
557                 /* Even if the submodule is checked out and the commit is
558                  * present, make sure it is reachable from a ref. */
559                 struct child_process cp;
560                 const char *argv[] = {"rev-list", "-n", "1", NULL, "--not", "--all", NULL};
561                 struct strbuf buf = STRBUF_INIT;
562
563                 argv[3] = sha1_to_hex(sha1);
564                 memset(&cp, 0, sizeof(cp));
565                 cp.argv = argv;
566                 cp.env = local_repo_env;
567                 cp.git_cmd = 1;
568                 cp.no_stdin = 1;
569                 cp.out = -1;
570                 cp.dir = path;
571                 if (!run_command(&cp) && !strbuf_read(&buf, cp.out, 1024))
572                         is_present = 1;
573
574                 close(cp.out);
575                 strbuf_release(&buf);
576         }
577         return is_present;
578 }
579
580 static void submodule_collect_changed_cb(struct diff_queue_struct *q,
581                                          struct diff_options *options,
582                                          void *data)
583 {
584         int i;
585         for (i = 0; i < q->nr; i++) {
586                 struct diff_filepair *p = q->queue[i];
587                 if (!S_ISGITLINK(p->two->mode))
588                         continue;
589
590                 if (S_ISGITLINK(p->one->mode)) {
591                         /* NEEDSWORK: We should honor the name configured in
592                          * the .gitmodules file of the commit we are examining
593                          * here to be able to correctly follow submodules
594                          * being moved around. */
595                         struct string_list_item *path;
596                         path = unsorted_string_list_lookup(&changed_submodule_paths, p->two->path);
597                         if (!path && !is_submodule_commit_present(p->two->path, p->two->sha1))
598                                 string_list_append(&changed_submodule_paths, xstrdup(p->two->path));
599                 } else {
600                         /* Submodule is new or was moved here */
601                         /* NEEDSWORK: When the .git directories of submodules
602                          * live inside the superprojects .git directory some
603                          * day we should fetch new submodules directly into
604                          * that location too when config or options request
605                          * that so they can be checked out from there. */
606                         continue;
607                 }
608         }
609 }
610
611 static int add_sha1_to_array(const char *ref, const unsigned char *sha1,
612                              int flags, void *data)
613 {
614         sha1_array_append(data, sha1);
615         return 0;
616 }
617
618 void check_for_new_submodule_commits(unsigned char new_sha1[20])
619 {
620         if (!initialized_fetch_ref_tips) {
621                 for_each_ref(add_sha1_to_array, &ref_tips_before_fetch);
622                 initialized_fetch_ref_tips = 1;
623         }
624
625         sha1_array_append(&ref_tips_after_fetch, new_sha1);
626 }
627
628 static void add_sha1_to_argv(const unsigned char sha1[20], void *data)
629 {
630         argv_array_push(data, sha1_to_hex(sha1));
631 }
632
633 static void calculate_changed_submodule_paths(void)
634 {
635         struct rev_info rev;
636         struct commit *commit;
637         struct argv_array argv = ARGV_ARRAY_INIT;
638
639         /* No need to check if there are no submodules configured */
640         if (!config_name_for_path.nr)
641                 return;
642
643         init_revisions(&rev, NULL);
644         argv_array_push(&argv, "--"); /* argv[0] program name */
645         sha1_array_for_each_unique(&ref_tips_after_fetch,
646                                    add_sha1_to_argv, &argv);
647         argv_array_push(&argv, "--not");
648         sha1_array_for_each_unique(&ref_tips_before_fetch,
649                                    add_sha1_to_argv, &argv);
650         setup_revisions(argv.argc, argv.argv, &rev, NULL);
651         if (prepare_revision_walk(&rev))
652                 die("revision walk setup failed");
653
654         /*
655          * Collect all submodules (whether checked out or not) for which new
656          * commits have been recorded upstream in "changed_submodule_paths".
657          */
658         while ((commit = get_revision(&rev))) {
659                 struct commit_list *parent = commit->parents;
660                 while (parent) {
661                         struct diff_options diff_opts;
662                         diff_setup(&diff_opts);
663                         DIFF_OPT_SET(&diff_opts, RECURSIVE);
664                         diff_opts.output_format |= DIFF_FORMAT_CALLBACK;
665                         diff_opts.format_callback = submodule_collect_changed_cb;
666                         diff_setup_done(&diff_opts);
667                         diff_tree_sha1(parent->item->object.sha1, commit->object.sha1, "", &diff_opts);
668                         diffcore_std(&diff_opts);
669                         diff_flush(&diff_opts);
670                         parent = parent->next;
671                 }
672         }
673
674         argv_array_clear(&argv);
675         sha1_array_clear(&ref_tips_before_fetch);
676         sha1_array_clear(&ref_tips_after_fetch);
677         initialized_fetch_ref_tips = 0;
678 }
679
680 int fetch_populated_submodules(const struct argv_array *options,
681                                const char *prefix, int command_line_option,
682                                int quiet)
683 {
684         int i, result = 0;
685         struct child_process cp;
686         struct argv_array argv = ARGV_ARRAY_INIT;
687         struct string_list_item *name_for_path;
688         const char *work_tree = get_git_work_tree();
689         if (!work_tree)
690                 goto out;
691
692         if (read_cache() < 0)
693                 die("index file corrupt");
694
695         argv_array_push(&argv, "fetch");
696         for (i = 0; i < options->argc; i++)
697                 argv_array_push(&argv, options->argv[i]);
698         argv_array_push(&argv, "--recurse-submodules-default");
699         /* default value, "--submodule-prefix" and its value are added later */
700
701         memset(&cp, 0, sizeof(cp));
702         cp.env = local_repo_env;
703         cp.git_cmd = 1;
704         cp.no_stdin = 1;
705
706         calculate_changed_submodule_paths();
707
708         for (i = 0; i < active_nr; i++) {
709                 struct strbuf submodule_path = STRBUF_INIT;
710                 struct strbuf submodule_git_dir = STRBUF_INIT;
711                 struct strbuf submodule_prefix = STRBUF_INIT;
712                 struct cache_entry *ce = active_cache[i];
713                 const char *git_dir, *name, *default_argv;
714
715                 if (!S_ISGITLINK(ce->ce_mode))
716                         continue;
717
718                 name = ce->name;
719                 name_for_path = unsorted_string_list_lookup(&config_name_for_path, ce->name);
720                 if (name_for_path)
721                         name = name_for_path->util;
722
723                 default_argv = "yes";
724                 if (command_line_option == RECURSE_SUBMODULES_DEFAULT) {
725                         struct string_list_item *fetch_recurse_submodules_option;
726                         fetch_recurse_submodules_option = unsorted_string_list_lookup(&config_fetch_recurse_submodules_for_name, name);
727                         if (fetch_recurse_submodules_option) {
728                                 if ((intptr_t)fetch_recurse_submodules_option->util == RECURSE_SUBMODULES_OFF)
729                                         continue;
730                                 if ((intptr_t)fetch_recurse_submodules_option->util == RECURSE_SUBMODULES_ON_DEMAND) {
731                                         if (!unsorted_string_list_lookup(&changed_submodule_paths, ce->name))
732                                                 continue;
733                                         default_argv = "on-demand";
734                                 }
735                         } else {
736                                 if ((config_fetch_recurse_submodules == RECURSE_SUBMODULES_OFF) ||
737                                     gitmodules_is_unmerged)
738                                         continue;
739                                 if (config_fetch_recurse_submodules == RECURSE_SUBMODULES_ON_DEMAND) {
740                                         if (!unsorted_string_list_lookup(&changed_submodule_paths, ce->name))
741                                                 continue;
742                                         default_argv = "on-demand";
743                                 }
744                         }
745                 } else if (command_line_option == RECURSE_SUBMODULES_ON_DEMAND) {
746                         if (!unsorted_string_list_lookup(&changed_submodule_paths, ce->name))
747                                 continue;
748                         default_argv = "on-demand";
749                 }
750
751                 strbuf_addf(&submodule_path, "%s/%s", work_tree, ce->name);
752                 strbuf_addf(&submodule_git_dir, "%s/.git", submodule_path.buf);
753                 strbuf_addf(&submodule_prefix, "%s%s/", prefix, ce->name);
754                 git_dir = read_gitfile(submodule_git_dir.buf);
755                 if (!git_dir)
756                         git_dir = submodule_git_dir.buf;
757                 if (is_directory(git_dir)) {
758                         if (!quiet)
759                                 printf("Fetching submodule %s%s\n", prefix, ce->name);
760                         cp.dir = submodule_path.buf;
761                         argv_array_push(&argv, default_argv);
762                         argv_array_push(&argv, "--submodule-prefix");
763                         argv_array_push(&argv, submodule_prefix.buf);
764                         cp.argv = argv.argv;
765                         if (run_command(&cp))
766                                 result = 1;
767                         argv_array_pop(&argv);
768                         argv_array_pop(&argv);
769                         argv_array_pop(&argv);
770                 }
771                 strbuf_release(&submodule_path);
772                 strbuf_release(&submodule_git_dir);
773                 strbuf_release(&submodule_prefix);
774         }
775         argv_array_clear(&argv);
776 out:
777         string_list_clear(&changed_submodule_paths, 1);
778         return result;
779 }
780
781 unsigned is_submodule_modified(const char *path, int ignore_untracked)
782 {
783         ssize_t len;
784         struct child_process cp;
785         const char *argv[] = {
786                 "status",
787                 "--porcelain",
788                 NULL,
789                 NULL,
790         };
791         struct strbuf buf = STRBUF_INIT;
792         unsigned dirty_submodule = 0;
793         const char *line, *next_line;
794         const char *git_dir;
795
796         strbuf_addf(&buf, "%s/.git", path);
797         git_dir = read_gitfile(buf.buf);
798         if (!git_dir)
799                 git_dir = buf.buf;
800         if (!is_directory(git_dir)) {
801                 strbuf_release(&buf);
802                 /* The submodule is not checked out, so it is not modified */
803                 return 0;
804
805         }
806         strbuf_reset(&buf);
807
808         if (ignore_untracked)
809                 argv[2] = "-uno";
810
811         memset(&cp, 0, sizeof(cp));
812         cp.argv = argv;
813         cp.env = local_repo_env;
814         cp.git_cmd = 1;
815         cp.no_stdin = 1;
816         cp.out = -1;
817         cp.dir = path;
818         if (start_command(&cp))
819                 die("Could not run 'git status --porcelain' in submodule %s", path);
820
821         len = strbuf_read(&buf, cp.out, 1024);
822         line = buf.buf;
823         while (len > 2) {
824                 if ((line[0] == '?') && (line[1] == '?')) {
825                         dirty_submodule |= DIRTY_SUBMODULE_UNTRACKED;
826                         if (dirty_submodule & DIRTY_SUBMODULE_MODIFIED)
827                                 break;
828                 } else {
829                         dirty_submodule |= DIRTY_SUBMODULE_MODIFIED;
830                         if (ignore_untracked ||
831                             (dirty_submodule & DIRTY_SUBMODULE_UNTRACKED))
832                                 break;
833                 }
834                 next_line = strchr(line, '\n');
835                 if (!next_line)
836                         break;
837                 next_line++;
838                 len -= (next_line - line);
839                 line = next_line;
840         }
841         close(cp.out);
842
843         if (finish_command(&cp))
844                 die("'git status --porcelain' failed in submodule %s", path);
845
846         strbuf_release(&buf);
847         return dirty_submodule;
848 }
849
850 int submodule_uses_gitfile(const char *path)
851 {
852         struct child_process cp;
853         const char *argv[] = {
854                 "submodule",
855                 "foreach",
856                 "--quiet",
857                 "--recursive",
858                 "test -f .git",
859                 NULL,
860         };
861         struct strbuf buf = STRBUF_INIT;
862         const char *git_dir;
863
864         strbuf_addf(&buf, "%s/.git", path);
865         git_dir = read_gitfile(buf.buf);
866         if (!git_dir) {
867                 strbuf_release(&buf);
868                 return 0;
869         }
870         strbuf_release(&buf);
871
872         /* Now test that all nested submodules use a gitfile too */
873         memset(&cp, 0, sizeof(cp));
874         cp.argv = argv;
875         cp.env = local_repo_env;
876         cp.git_cmd = 1;
877         cp.no_stdin = 1;
878         cp.no_stderr = 1;
879         cp.no_stdout = 1;
880         cp.dir = path;
881         if (run_command(&cp))
882                 return 0;
883
884         return 1;
885 }
886
887 int ok_to_remove_submodule(const char *path)
888 {
889         struct stat st;
890         ssize_t len;
891         struct child_process cp;
892         const char *argv[] = {
893                 "status",
894                 "--porcelain",
895                 "-u",
896                 "--ignore-submodules=none",
897                 NULL,
898         };
899         struct strbuf buf = STRBUF_INIT;
900         int ok_to_remove = 1;
901
902         if ((lstat(path, &st) < 0) || is_empty_dir(path))
903                 return 1;
904
905         if (!submodule_uses_gitfile(path))
906                 return 0;
907
908         memset(&cp, 0, sizeof(cp));
909         cp.argv = argv;
910         cp.env = local_repo_env;
911         cp.git_cmd = 1;
912         cp.no_stdin = 1;
913         cp.out = -1;
914         cp.dir = path;
915         if (start_command(&cp))
916                 die("Could not run 'git status --porcelain -uall --ignore-submodules=none' in submodule %s", path);
917
918         len = strbuf_read(&buf, cp.out, 1024);
919         if (len > 2)
920                 ok_to_remove = 0;
921         close(cp.out);
922
923         if (finish_command(&cp))
924                 die("'git status --porcelain -uall --ignore-submodules=none' failed in submodule %s", path);
925
926         strbuf_release(&buf);
927         return ok_to_remove;
928 }
929
930 static int find_first_merges(struct object_array *result, const char *path,
931                 struct commit *a, struct commit *b)
932 {
933         int i, j;
934         struct object_array merges = OBJECT_ARRAY_INIT;
935         struct commit *commit;
936         int contains_another;
937
938         char merged_revision[42];
939         const char *rev_args[] = { "rev-list", "--merges", "--ancestry-path",
940                                    "--all", merged_revision, NULL };
941         struct rev_info revs;
942         struct setup_revision_opt rev_opts;
943
944         memset(result, 0, sizeof(struct object_array));
945         memset(&rev_opts, 0, sizeof(rev_opts));
946
947         /* get all revisions that merge commit a */
948         snprintf(merged_revision, sizeof(merged_revision), "^%s",
949                         sha1_to_hex(a->object.sha1));
950         init_revisions(&revs, NULL);
951         rev_opts.submodule = path;
952         setup_revisions(sizeof(rev_args)/sizeof(char *)-1, rev_args, &revs, &rev_opts);
953
954         /* save all revisions from the above list that contain b */
955         if (prepare_revision_walk(&revs))
956                 die("revision walk setup failed");
957         while ((commit = get_revision(&revs)) != NULL) {
958                 struct object *o = &(commit->object);
959                 if (in_merge_bases(b, commit))
960                         add_object_array(o, NULL, &merges);
961         }
962         reset_revision_walk();
963
964         /* Now we've got all merges that contain a and b. Prune all
965          * merges that contain another found merge and save them in
966          * result.
967          */
968         for (i = 0; i < merges.nr; i++) {
969                 struct commit *m1 = (struct commit *) merges.objects[i].item;
970
971                 contains_another = 0;
972                 for (j = 0; j < merges.nr; j++) {
973                         struct commit *m2 = (struct commit *) merges.objects[j].item;
974                         if (i != j && in_merge_bases(m2, m1)) {
975                                 contains_another = 1;
976                                 break;
977                         }
978                 }
979
980                 if (!contains_another)
981                         add_object_array(merges.objects[i].item, NULL, result);
982         }
983
984         free(merges.objects);
985         return result->nr;
986 }
987
988 static void print_commit(struct commit *commit)
989 {
990         struct strbuf sb = STRBUF_INIT;
991         struct pretty_print_context ctx = {0};
992         ctx.date_mode = DATE_NORMAL;
993         format_commit_message(commit, " %h: %m %s", &sb, &ctx);
994         fprintf(stderr, "%s\n", sb.buf);
995         strbuf_release(&sb);
996 }
997
998 #define MERGE_WARNING(path, msg) \
999         warning("Failed to merge submodule %s (%s)", path, msg);
1000
1001 int merge_submodule(unsigned char result[20], const char *path,
1002                     const unsigned char base[20], const unsigned char a[20],
1003                     const unsigned char b[20], int search)
1004 {
1005         struct commit *commit_base, *commit_a, *commit_b;
1006         int parent_count;
1007         struct object_array merges;
1008
1009         int i;
1010
1011         /* store a in result in case we fail */
1012         hashcpy(result, a);
1013
1014         /* we can not handle deletion conflicts */
1015         if (is_null_sha1(base))
1016                 return 0;
1017         if (is_null_sha1(a))
1018                 return 0;
1019         if (is_null_sha1(b))
1020                 return 0;
1021
1022         if (add_submodule_odb(path)) {
1023                 MERGE_WARNING(path, "not checked out");
1024                 return 0;
1025         }
1026
1027         if (!(commit_base = lookup_commit_reference(base)) ||
1028             !(commit_a = lookup_commit_reference(a)) ||
1029             !(commit_b = lookup_commit_reference(b))) {
1030                 MERGE_WARNING(path, "commits not present");
1031                 return 0;
1032         }
1033
1034         /* check whether both changes are forward */
1035         if (!in_merge_bases(commit_base, commit_a) ||
1036             !in_merge_bases(commit_base, commit_b)) {
1037                 MERGE_WARNING(path, "commits don't follow merge-base");
1038                 return 0;
1039         }
1040
1041         /* Case #1: a is contained in b or vice versa */
1042         if (in_merge_bases(commit_a, commit_b)) {
1043                 hashcpy(result, b);
1044                 return 1;
1045         }
1046         if (in_merge_bases(commit_b, commit_a)) {
1047                 hashcpy(result, a);
1048                 return 1;
1049         }
1050
1051         /*
1052          * Case #2: There are one or more merges that contain a and b in
1053          * the submodule. If there is only one, then present it as a
1054          * suggestion to the user, but leave it marked unmerged so the
1055          * user needs to confirm the resolution.
1056          */
1057
1058         /* Skip the search if makes no sense to the calling context.  */
1059         if (!search)
1060                 return 0;
1061
1062         /* find commit which merges them */
1063         parent_count = find_first_merges(&merges, path, commit_a, commit_b);
1064         switch (parent_count) {
1065         case 0:
1066                 MERGE_WARNING(path, "merge following commits not found");
1067                 break;
1068
1069         case 1:
1070                 MERGE_WARNING(path, "not fast-forward");
1071                 fprintf(stderr, "Found a possible merge resolution "
1072                                 "for the submodule:\n");
1073                 print_commit((struct commit *) merges.objects[0].item);
1074                 fprintf(stderr,
1075                         "If this is correct simply add it to the index "
1076                         "for example\n"
1077                         "by using:\n\n"
1078                         "  git update-index --cacheinfo 160000 %s \"%s\"\n\n"
1079                         "which will accept this suggestion.\n",
1080                         sha1_to_hex(merges.objects[0].item->sha1), path);
1081                 break;
1082
1083         default:
1084                 MERGE_WARNING(path, "multiple merges found");
1085                 for (i = 0; i < merges.nr; i++)
1086                         print_commit((struct commit *) merges.objects[i].item);
1087         }
1088
1089         free(merges.objects);
1090         return 0;
1091 }
1092
1093 /* Update gitfile and core.worktree setting to connect work tree and git dir */
1094 void connect_work_tree_and_git_dir(const char *work_tree, const char *git_dir)
1095 {
1096         struct strbuf file_name = STRBUF_INIT;
1097         struct strbuf rel_path = STRBUF_INIT;
1098         const char *real_work_tree = xstrdup(real_path(work_tree));
1099         FILE *fp;
1100
1101         /* Update gitfile */
1102         strbuf_addf(&file_name, "%s/.git", work_tree);
1103         fp = fopen(file_name.buf, "w");
1104         if (!fp)
1105                 die(_("Could not create git link %s"), file_name.buf);
1106         fprintf(fp, "gitdir: %s\n", relative_path(git_dir, real_work_tree,
1107                                                   &rel_path));
1108         fclose(fp);
1109
1110         /* Update core.worktree setting */
1111         strbuf_reset(&file_name);
1112         strbuf_addf(&file_name, "%s/config", git_dir);
1113         if (git_config_set_in_file(file_name.buf, "core.worktree",
1114                                    relative_path(real_work_tree, git_dir,
1115                                                  &rel_path)))
1116                 die(_("Could not set core.worktree in %s"),
1117                     file_name.buf);
1118
1119         strbuf_release(&file_name);
1120         strbuf_release(&rel_path);
1121         free((void *)real_work_tree);
1122 }