clone: clarify option_reference as required
[git] / submodule.c
1 #include "cache.h"
2 #include "submodule-config.h"
3 #include "submodule.h"
4 #include "dir.h"
5 #include "diff.h"
6 #include "commit.h"
7 #include "revision.h"
8 #include "run-command.h"
9 #include "diffcore.h"
10 #include "refs.h"
11 #include "string-list.h"
12 #include "sha1-array.h"
13 #include "argv-array.h"
14 #include "blob.h"
15 #include "thread-utils.h"
16 #include "quote.h"
17
18 static int config_fetch_recurse_submodules = RECURSE_SUBMODULES_ON_DEMAND;
19 static int parallel_jobs = 1;
20 static struct string_list changed_submodule_paths = STRING_LIST_INIT_NODUP;
21 static int initialized_fetch_ref_tips;
22 static struct sha1_array ref_tips_before_fetch;
23 static struct sha1_array ref_tips_after_fetch;
24
25 /*
26  * The following flag is set if the .gitmodules file is unmerged. We then
27  * disable recursion for all submodules where .git/config doesn't have a
28  * matching config entry because we can't guess what might be configured in
29  * .gitmodules unless the user resolves the conflict. When a command line
30  * option is given (which always overrides configuration) this flag will be
31  * ignored.
32  */
33 static int gitmodules_is_unmerged;
34
35 /*
36  * This flag is set if the .gitmodules file had unstaged modifications on
37  * startup. This must be checked before allowing modifications to the
38  * .gitmodules file with the intention to stage them later, because when
39  * continuing we would stage the modifications the user didn't stage herself
40  * too. That might change in a future version when we learn to stage the
41  * changes we do ourselves without staging any previous modifications.
42  */
43 static int gitmodules_is_modified;
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         const struct submodule *submodule;
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         submodule = submodule_from_path(null_sha1, oldpath);
67         if (!submodule || !submodule->name) {
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, submodule->name);
73         strbuf_addstr(&entry, ".path");
74         if (git_config_set_in_file_gently(".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 /*
85  * Try to remove the "submodule.<name>" section from .gitmodules where the given
86  * path is configured. Return 0 only if a .gitmodules file was found, a section
87  * with the correct path=<path> setting was found and we could remove it.
88  */
89 int remove_path_from_gitmodules(const char *path)
90 {
91         struct strbuf sect = STRBUF_INIT;
92         const struct submodule *submodule;
93
94         if (!file_exists(".gitmodules")) /* Do nothing without .gitmodules */
95                 return -1;
96
97         if (gitmodules_is_unmerged)
98                 die(_("Cannot change unmerged .gitmodules, resolve merge conflicts first"));
99
100         submodule = submodule_from_path(null_sha1, path);
101         if (!submodule || !submodule->name) {
102                 warning(_("Could not find section in .gitmodules where path=%s"), path);
103                 return -1;
104         }
105         strbuf_addstr(&sect, "submodule.");
106         strbuf_addstr(&sect, submodule->name);
107         if (git_config_rename_section_in_file(".gitmodules", sect.buf, NULL) < 0) {
108                 /* Maybe the user already did that, don't error out here */
109                 warning(_("Could not remove .gitmodules entry for %s"), path);
110                 strbuf_release(&sect);
111                 return -1;
112         }
113         strbuf_release(&sect);
114         return 0;
115 }
116
117 void stage_updated_gitmodules(void)
118 {
119         if (add_file_to_cache(".gitmodules", 0))
120                 die(_("staging updated .gitmodules failed"));
121 }
122
123 static int add_submodule_odb(const char *path)
124 {
125         struct strbuf objects_directory = STRBUF_INIT;
126         struct alternate_object_database *alt_odb;
127         int ret = 0;
128         size_t alloc;
129
130         strbuf_git_path_submodule(&objects_directory, path, "objects/");
131         if (!is_directory(objects_directory.buf)) {
132                 ret = -1;
133                 goto done;
134         }
135         /* avoid adding it twice */
136         prepare_alt_odb();
137         for (alt_odb = alt_odb_list; alt_odb; alt_odb = alt_odb->next)
138                 if (alt_odb->name - alt_odb->base == objects_directory.len &&
139                                 !strncmp(alt_odb->base, objects_directory.buf,
140                                         objects_directory.len))
141                         goto done;
142
143         alloc = st_add(objects_directory.len, 42); /* for "12/345..." sha1 */
144         alt_odb = xmalloc(st_add(sizeof(*alt_odb), alloc));
145         alt_odb->next = alt_odb_list;
146         xsnprintf(alt_odb->base, alloc, "%s", objects_directory.buf);
147         alt_odb->name = alt_odb->base + objects_directory.len;
148         alt_odb->name[2] = '/';
149         alt_odb->name[40] = '\0';
150         alt_odb->name[41] = '\0';
151         alt_odb_list = alt_odb;
152
153         /* add possible alternates from the submodule */
154         read_info_alternates(objects_directory.buf, 0);
155 done:
156         strbuf_release(&objects_directory);
157         return ret;
158 }
159
160 void set_diffopt_flags_from_submodule_config(struct diff_options *diffopt,
161                                              const char *path)
162 {
163         const struct submodule *submodule = submodule_from_path(null_sha1, path);
164         if (submodule) {
165                 if (submodule->ignore)
166                         handle_ignore_submodules_arg(diffopt, submodule->ignore);
167                 else if (gitmodules_is_unmerged)
168                         DIFF_OPT_SET(diffopt, IGNORE_SUBMODULES);
169         }
170 }
171
172 int submodule_config(const char *var, const char *value, void *cb)
173 {
174         if (!strcmp(var, "submodule.fetchjobs")) {
175                 parallel_jobs = git_config_int(var, value);
176                 if (parallel_jobs < 0)
177                         die(_("negative values not allowed for submodule.fetchJobs"));
178                 return 0;
179         } else if (starts_with(var, "submodule."))
180                 return parse_submodule_config_option(var, value);
181         else if (!strcmp(var, "fetch.recursesubmodules")) {
182                 config_fetch_recurse_submodules = parse_fetch_recurse_submodules_arg(var, value);
183                 return 0;
184         }
185         return 0;
186 }
187
188 void gitmodules_config(void)
189 {
190         const char *work_tree = get_git_work_tree();
191         if (work_tree) {
192                 struct strbuf gitmodules_path = STRBUF_INIT;
193                 int pos;
194                 strbuf_addstr(&gitmodules_path, work_tree);
195                 strbuf_addstr(&gitmodules_path, "/.gitmodules");
196                 if (read_cache() < 0)
197                         die("index file corrupt");
198                 pos = cache_name_pos(".gitmodules", 11);
199                 if (pos < 0) { /* .gitmodules not found or isn't merged */
200                         pos = -1 - pos;
201                         if (active_nr > pos) {  /* there is a .gitmodules */
202                                 const struct cache_entry *ce = active_cache[pos];
203                                 if (ce_namelen(ce) == 11 &&
204                                     !memcmp(ce->name, ".gitmodules", 11))
205                                         gitmodules_is_unmerged = 1;
206                         }
207                 } else if (pos < active_nr) {
208                         struct stat st;
209                         if (lstat(".gitmodules", &st) == 0 &&
210                             ce_match_stat(active_cache[pos], &st, 0) & DATA_CHANGED)
211                                 gitmodules_is_modified = 1;
212                 }
213
214                 if (!gitmodules_is_unmerged)
215                         git_config_from_file(submodule_config, gitmodules_path.buf, NULL);
216                 strbuf_release(&gitmodules_path);
217         }
218 }
219
220 int parse_submodule_update_strategy(const char *value,
221                 struct submodule_update_strategy *dst)
222 {
223         free((void*)dst->command);
224         dst->command = NULL;
225         if (!strcmp(value, "none"))
226                 dst->type = SM_UPDATE_NONE;
227         else if (!strcmp(value, "checkout"))
228                 dst->type = SM_UPDATE_CHECKOUT;
229         else if (!strcmp(value, "rebase"))
230                 dst->type = SM_UPDATE_REBASE;
231         else if (!strcmp(value, "merge"))
232                 dst->type = SM_UPDATE_MERGE;
233         else if (skip_prefix(value, "!", &value)) {
234                 dst->type = SM_UPDATE_COMMAND;
235                 dst->command = xstrdup(value);
236         } else
237                 return -1;
238         return 0;
239 }
240
241 const char *submodule_strategy_to_string(const struct submodule_update_strategy *s)
242 {
243         struct strbuf sb = STRBUF_INIT;
244         switch (s->type) {
245         case SM_UPDATE_CHECKOUT:
246                 return "checkout";
247         case SM_UPDATE_MERGE:
248                 return "merge";
249         case SM_UPDATE_REBASE:
250                 return "rebase";
251         case SM_UPDATE_NONE:
252                 return "none";
253         case SM_UPDATE_UNSPECIFIED:
254                 return NULL;
255         case SM_UPDATE_COMMAND:
256                 strbuf_addf(&sb, "!%s", s->command);
257                 return strbuf_detach(&sb, NULL);
258         }
259         return NULL;
260 }
261
262 void handle_ignore_submodules_arg(struct diff_options *diffopt,
263                                   const char *arg)
264 {
265         DIFF_OPT_CLR(diffopt, IGNORE_SUBMODULES);
266         DIFF_OPT_CLR(diffopt, IGNORE_UNTRACKED_IN_SUBMODULES);
267         DIFF_OPT_CLR(diffopt, IGNORE_DIRTY_SUBMODULES);
268
269         if (!strcmp(arg, "all"))
270                 DIFF_OPT_SET(diffopt, IGNORE_SUBMODULES);
271         else if (!strcmp(arg, "untracked"))
272                 DIFF_OPT_SET(diffopt, IGNORE_UNTRACKED_IN_SUBMODULES);
273         else if (!strcmp(arg, "dirty"))
274                 DIFF_OPT_SET(diffopt, IGNORE_DIRTY_SUBMODULES);
275         else if (strcmp(arg, "none"))
276                 die("bad --ignore-submodules argument: %s", arg);
277 }
278
279 static int prepare_submodule_summary(struct rev_info *rev, const char *path,
280                 struct commit *left, struct commit *right,
281                 int *fast_forward, int *fast_backward)
282 {
283         struct commit_list *merge_bases, *list;
284
285         init_revisions(rev, NULL);
286         setup_revisions(0, NULL, rev, NULL);
287         rev->left_right = 1;
288         rev->first_parent_only = 1;
289         left->object.flags |= SYMMETRIC_LEFT;
290         add_pending_object(rev, &left->object, path);
291         add_pending_object(rev, &right->object, path);
292         merge_bases = get_merge_bases(left, right);
293         if (merge_bases) {
294                 if (merge_bases->item == left)
295                         *fast_forward = 1;
296                 else if (merge_bases->item == right)
297                         *fast_backward = 1;
298         }
299         for (list = merge_bases; list; list = list->next) {
300                 list->item->object.flags |= UNINTERESTING;
301                 add_pending_object(rev, &list->item->object,
302                         oid_to_hex(&list->item->object.oid));
303         }
304         return prepare_revision_walk(rev);
305 }
306
307 static void print_submodule_summary(struct rev_info *rev, FILE *f,
308                 const char *line_prefix,
309                 const char *del, const char *add, const char *reset)
310 {
311         static const char format[] = "  %m %s";
312         struct strbuf sb = STRBUF_INIT;
313         struct commit *commit;
314
315         while ((commit = get_revision(rev))) {
316                 struct pretty_print_context ctx = {0};
317                 ctx.date_mode = rev->date_mode;
318                 ctx.output_encoding = get_log_output_encoding();
319                 strbuf_setlen(&sb, 0);
320                 strbuf_addstr(&sb, line_prefix);
321                 if (commit->object.flags & SYMMETRIC_LEFT) {
322                         if (del)
323                                 strbuf_addstr(&sb, del);
324                 }
325                 else if (add)
326                         strbuf_addstr(&sb, add);
327                 format_commit_message(commit, format, &sb, &ctx);
328                 if (reset)
329                         strbuf_addstr(&sb, reset);
330                 strbuf_addch(&sb, '\n');
331                 fprintf(f, "%s", sb.buf);
332         }
333         strbuf_release(&sb);
334 }
335
336 void show_submodule_summary(FILE *f, const char *path,
337                 const char *line_prefix,
338                 unsigned char one[20], unsigned char two[20],
339                 unsigned dirty_submodule, const char *meta,
340                 const char *del, const char *add, const char *reset)
341 {
342         struct rev_info rev;
343         struct commit *left = NULL, *right = NULL;
344         const char *message = NULL;
345         struct strbuf sb = STRBUF_INIT;
346         int fast_forward = 0, fast_backward = 0;
347
348         if (is_null_sha1(two))
349                 message = "(submodule deleted)";
350         else if (add_submodule_odb(path))
351                 message = "(not checked out)";
352         else if (is_null_sha1(one))
353                 message = "(new submodule)";
354         else if (!(left = lookup_commit_reference(one)) ||
355                  !(right = lookup_commit_reference(two)))
356                 message = "(commits not present)";
357         else if (prepare_submodule_summary(&rev, path, left, right,
358                                            &fast_forward, &fast_backward))
359                 message = "(revision walker failed)";
360
361         if (dirty_submodule & DIRTY_SUBMODULE_UNTRACKED)
362                 fprintf(f, "%sSubmodule %s contains untracked content\n",
363                         line_prefix, path);
364         if (dirty_submodule & DIRTY_SUBMODULE_MODIFIED)
365                 fprintf(f, "%sSubmodule %s contains modified content\n",
366                         line_prefix, path);
367
368         if (!hashcmp(one, two)) {
369                 strbuf_release(&sb);
370                 return;
371         }
372
373         strbuf_addf(&sb, "%s%sSubmodule %s %s..", line_prefix, meta, path,
374                         find_unique_abbrev(one, DEFAULT_ABBREV));
375         if (!fast_backward && !fast_forward)
376                 strbuf_addch(&sb, '.');
377         strbuf_addf(&sb, "%s", find_unique_abbrev(two, DEFAULT_ABBREV));
378         if (message)
379                 strbuf_addf(&sb, " %s%s\n", message, reset);
380         else
381                 strbuf_addf(&sb, "%s:%s\n", fast_backward ? " (rewind)" : "", reset);
382         fwrite(sb.buf, sb.len, 1, f);
383
384         if (!message) /* only NULL if we succeeded in setting up the walk */
385                 print_submodule_summary(&rev, f, line_prefix, del, add, reset);
386         if (left)
387                 clear_commit_marks(left, ~0);
388         if (right)
389                 clear_commit_marks(right, ~0);
390
391         strbuf_release(&sb);
392 }
393
394 void set_config_fetch_recurse_submodules(int value)
395 {
396         config_fetch_recurse_submodules = value;
397 }
398
399 static int has_remote(const char *refname, const struct object_id *oid,
400                       int flags, void *cb_data)
401 {
402         return 1;
403 }
404
405 static int submodule_needs_pushing(const char *path, const unsigned char sha1[20])
406 {
407         if (add_submodule_odb(path) || !lookup_commit_reference(sha1))
408                 return 0;
409
410         if (for_each_remote_ref_submodule(path, has_remote, NULL) > 0) {
411                 struct child_process cp = CHILD_PROCESS_INIT;
412                 const char *argv[] = {"rev-list", NULL, "--not", "--remotes", "-n", "1" , NULL};
413                 struct strbuf buf = STRBUF_INIT;
414                 int needs_pushing = 0;
415
416                 argv[1] = sha1_to_hex(sha1);
417                 cp.argv = argv;
418                 prepare_submodule_repo_env(&cp.env_array);
419                 cp.git_cmd = 1;
420                 cp.no_stdin = 1;
421                 cp.out = -1;
422                 cp.dir = path;
423                 if (start_command(&cp))
424                         die("Could not run 'git rev-list %s --not --remotes -n 1' command in submodule %s",
425                                 sha1_to_hex(sha1), path);
426                 if (strbuf_read(&buf, cp.out, 41))
427                         needs_pushing = 1;
428                 finish_command(&cp);
429                 close(cp.out);
430                 strbuf_release(&buf);
431                 return needs_pushing;
432         }
433
434         return 0;
435 }
436
437 static void collect_submodules_from_diff(struct diff_queue_struct *q,
438                                          struct diff_options *options,
439                                          void *data)
440 {
441         int i;
442         struct string_list *needs_pushing = data;
443
444         for (i = 0; i < q->nr; i++) {
445                 struct diff_filepair *p = q->queue[i];
446                 if (!S_ISGITLINK(p->two->mode))
447                         continue;
448                 if (submodule_needs_pushing(p->two->path, p->two->oid.hash))
449                         string_list_insert(needs_pushing, p->two->path);
450         }
451 }
452
453 static void find_unpushed_submodule_commits(struct commit *commit,
454                 struct string_list *needs_pushing)
455 {
456         struct rev_info rev;
457
458         init_revisions(&rev, NULL);
459         rev.diffopt.output_format |= DIFF_FORMAT_CALLBACK;
460         rev.diffopt.format_callback = collect_submodules_from_diff;
461         rev.diffopt.format_callback_data = needs_pushing;
462         diff_tree_combined_merge(commit, 1, &rev);
463 }
464
465 int find_unpushed_submodules(unsigned char new_sha1[20],
466                 const char *remotes_name, struct string_list *needs_pushing)
467 {
468         struct rev_info rev;
469         struct commit *commit;
470         const char *argv[] = {NULL, NULL, "--not", "NULL", NULL};
471         int argc = ARRAY_SIZE(argv) - 1;
472         char *sha1_copy;
473
474         struct strbuf remotes_arg = STRBUF_INIT;
475
476         strbuf_addf(&remotes_arg, "--remotes=%s", remotes_name);
477         init_revisions(&rev, NULL);
478         sha1_copy = xstrdup(sha1_to_hex(new_sha1));
479         argv[1] = sha1_copy;
480         argv[3] = remotes_arg.buf;
481         setup_revisions(argc, argv, &rev, NULL);
482         if (prepare_revision_walk(&rev))
483                 die("revision walk setup failed");
484
485         while ((commit = get_revision(&rev)) != NULL)
486                 find_unpushed_submodule_commits(commit, needs_pushing);
487
488         reset_revision_walk();
489         free(sha1_copy);
490         strbuf_release(&remotes_arg);
491
492         return needs_pushing->nr;
493 }
494
495 static int push_submodule(const char *path)
496 {
497         if (add_submodule_odb(path))
498                 return 1;
499
500         if (for_each_remote_ref_submodule(path, has_remote, NULL) > 0) {
501                 struct child_process cp = CHILD_PROCESS_INIT;
502                 const char *argv[] = {"push", NULL};
503
504                 cp.argv = argv;
505                 prepare_submodule_repo_env(&cp.env_array);
506                 cp.git_cmd = 1;
507                 cp.no_stdin = 1;
508                 cp.dir = path;
509                 if (run_command(&cp))
510                         return 0;
511                 close(cp.out);
512         }
513
514         return 1;
515 }
516
517 int push_unpushed_submodules(unsigned char new_sha1[20], const char *remotes_name)
518 {
519         int i, ret = 1;
520         struct string_list needs_pushing = STRING_LIST_INIT_DUP;
521
522         if (!find_unpushed_submodules(new_sha1, remotes_name, &needs_pushing))
523                 return 1;
524
525         for (i = 0; i < needs_pushing.nr; i++) {
526                 const char *path = needs_pushing.items[i].string;
527                 fprintf(stderr, "Pushing submodule '%s'\n", path);
528                 if (!push_submodule(path)) {
529                         fprintf(stderr, "Unable to push submodule '%s'\n", path);
530                         ret = 0;
531                 }
532         }
533
534         string_list_clear(&needs_pushing, 0);
535
536         return ret;
537 }
538
539 static int is_submodule_commit_present(const char *path, unsigned char sha1[20])
540 {
541         int is_present = 0;
542         if (!add_submodule_odb(path) && lookup_commit_reference(sha1)) {
543                 /* Even if the submodule is checked out and the commit is
544                  * present, make sure it is reachable from a ref. */
545                 struct child_process cp = CHILD_PROCESS_INIT;
546                 const char *argv[] = {"rev-list", "-n", "1", NULL, "--not", "--all", NULL};
547                 struct strbuf buf = STRBUF_INIT;
548
549                 argv[3] = sha1_to_hex(sha1);
550                 cp.argv = argv;
551                 prepare_submodule_repo_env(&cp.env_array);
552                 cp.git_cmd = 1;
553                 cp.no_stdin = 1;
554                 cp.dir = path;
555                 if (!capture_command(&cp, &buf, 1024) && !buf.len)
556                         is_present = 1;
557
558                 strbuf_release(&buf);
559         }
560         return is_present;
561 }
562
563 static void submodule_collect_changed_cb(struct diff_queue_struct *q,
564                                          struct diff_options *options,
565                                          void *data)
566 {
567         int i;
568         for (i = 0; i < q->nr; i++) {
569                 struct diff_filepair *p = q->queue[i];
570                 if (!S_ISGITLINK(p->two->mode))
571                         continue;
572
573                 if (S_ISGITLINK(p->one->mode)) {
574                         /* NEEDSWORK: We should honor the name configured in
575                          * the .gitmodules file of the commit we are examining
576                          * here to be able to correctly follow submodules
577                          * being moved around. */
578                         struct string_list_item *path;
579                         path = unsorted_string_list_lookup(&changed_submodule_paths, p->two->path);
580                         if (!path && !is_submodule_commit_present(p->two->path, p->two->oid.hash))
581                                 string_list_append(&changed_submodule_paths, xstrdup(p->two->path));
582                 } else {
583                         /* Submodule is new or was moved here */
584                         /* NEEDSWORK: When the .git directories of submodules
585                          * live inside the superprojects .git directory some
586                          * day we should fetch new submodules directly into
587                          * that location too when config or options request
588                          * that so they can be checked out from there. */
589                         continue;
590                 }
591         }
592 }
593
594 static int add_sha1_to_array(const char *ref, const struct object_id *oid,
595                              int flags, void *data)
596 {
597         sha1_array_append(data, oid->hash);
598         return 0;
599 }
600
601 void check_for_new_submodule_commits(unsigned char new_sha1[20])
602 {
603         if (!initialized_fetch_ref_tips) {
604                 for_each_ref(add_sha1_to_array, &ref_tips_before_fetch);
605                 initialized_fetch_ref_tips = 1;
606         }
607
608         sha1_array_append(&ref_tips_after_fetch, new_sha1);
609 }
610
611 static void add_sha1_to_argv(const unsigned char sha1[20], void *data)
612 {
613         argv_array_push(data, sha1_to_hex(sha1));
614 }
615
616 static void calculate_changed_submodule_paths(void)
617 {
618         struct rev_info rev;
619         struct commit *commit;
620         struct argv_array argv = ARGV_ARRAY_INIT;
621
622         /* No need to check if there are no submodules configured */
623         if (!submodule_from_path(NULL, NULL))
624                 return;
625
626         init_revisions(&rev, NULL);
627         argv_array_push(&argv, "--"); /* argv[0] program name */
628         sha1_array_for_each_unique(&ref_tips_after_fetch,
629                                    add_sha1_to_argv, &argv);
630         argv_array_push(&argv, "--not");
631         sha1_array_for_each_unique(&ref_tips_before_fetch,
632                                    add_sha1_to_argv, &argv);
633         setup_revisions(argv.argc, argv.argv, &rev, NULL);
634         if (prepare_revision_walk(&rev))
635                 die("revision walk setup failed");
636
637         /*
638          * Collect all submodules (whether checked out or not) for which new
639          * commits have been recorded upstream in "changed_submodule_paths".
640          */
641         while ((commit = get_revision(&rev))) {
642                 struct commit_list *parent = commit->parents;
643                 while (parent) {
644                         struct diff_options diff_opts;
645                         diff_setup(&diff_opts);
646                         DIFF_OPT_SET(&diff_opts, RECURSIVE);
647                         diff_opts.output_format |= DIFF_FORMAT_CALLBACK;
648                         diff_opts.format_callback = submodule_collect_changed_cb;
649                         diff_setup_done(&diff_opts);
650                         diff_tree_sha1(parent->item->object.oid.hash, commit->object.oid.hash, "", &diff_opts);
651                         diffcore_std(&diff_opts);
652                         diff_flush(&diff_opts);
653                         parent = parent->next;
654                 }
655         }
656
657         argv_array_clear(&argv);
658         sha1_array_clear(&ref_tips_before_fetch);
659         sha1_array_clear(&ref_tips_after_fetch);
660         initialized_fetch_ref_tips = 0;
661 }
662
663 struct submodule_parallel_fetch {
664         int count;
665         struct argv_array args;
666         const char *work_tree;
667         const char *prefix;
668         int command_line_option;
669         int quiet;
670         int result;
671 };
672 #define SPF_INIT {0, ARGV_ARRAY_INIT, NULL, NULL, 0, 0, 0}
673
674 static int get_next_submodule(struct child_process *cp,
675                               struct strbuf *err, void *data, void **task_cb)
676 {
677         int ret = 0;
678         struct submodule_parallel_fetch *spf = data;
679
680         for (; spf->count < active_nr; spf->count++) {
681                 struct strbuf submodule_path = STRBUF_INIT;
682                 struct strbuf submodule_git_dir = STRBUF_INIT;
683                 struct strbuf submodule_prefix = STRBUF_INIT;
684                 const struct cache_entry *ce = active_cache[spf->count];
685                 const char *git_dir, *default_argv;
686                 const struct submodule *submodule;
687
688                 if (!S_ISGITLINK(ce->ce_mode))
689                         continue;
690
691                 submodule = submodule_from_path(null_sha1, ce->name);
692                 if (!submodule)
693                         submodule = submodule_from_name(null_sha1, ce->name);
694
695                 default_argv = "yes";
696                 if (spf->command_line_option == RECURSE_SUBMODULES_DEFAULT) {
697                         if (submodule &&
698                             submodule->fetch_recurse !=
699                                                 RECURSE_SUBMODULES_NONE) {
700                                 if (submodule->fetch_recurse ==
701                                                 RECURSE_SUBMODULES_OFF)
702                                         continue;
703                                 if (submodule->fetch_recurse ==
704                                                 RECURSE_SUBMODULES_ON_DEMAND) {
705                                         if (!unsorted_string_list_lookup(&changed_submodule_paths, ce->name))
706                                                 continue;
707                                         default_argv = "on-demand";
708                                 }
709                         } else {
710                                 if ((config_fetch_recurse_submodules == RECURSE_SUBMODULES_OFF) ||
711                                     gitmodules_is_unmerged)
712                                         continue;
713                                 if (config_fetch_recurse_submodules == RECURSE_SUBMODULES_ON_DEMAND) {
714                                         if (!unsorted_string_list_lookup(&changed_submodule_paths, ce->name))
715                                                 continue;
716                                         default_argv = "on-demand";
717                                 }
718                         }
719                 } else if (spf->command_line_option == RECURSE_SUBMODULES_ON_DEMAND) {
720                         if (!unsorted_string_list_lookup(&changed_submodule_paths, ce->name))
721                                 continue;
722                         default_argv = "on-demand";
723                 }
724
725                 strbuf_addf(&submodule_path, "%s/%s", spf->work_tree, ce->name);
726                 strbuf_addf(&submodule_git_dir, "%s/.git", submodule_path.buf);
727                 strbuf_addf(&submodule_prefix, "%s%s/", spf->prefix, ce->name);
728                 git_dir = read_gitfile(submodule_git_dir.buf);
729                 if (!git_dir)
730                         git_dir = submodule_git_dir.buf;
731                 if (is_directory(git_dir)) {
732                         child_process_init(cp);
733                         cp->dir = strbuf_detach(&submodule_path, NULL);
734                         prepare_submodule_repo_env(&cp->env_array);
735                         cp->git_cmd = 1;
736                         if (!spf->quiet)
737                                 strbuf_addf(err, "Fetching submodule %s%s\n",
738                                             spf->prefix, ce->name);
739                         argv_array_init(&cp->args);
740                         argv_array_pushv(&cp->args, spf->args.argv);
741                         argv_array_push(&cp->args, default_argv);
742                         argv_array_push(&cp->args, "--submodule-prefix");
743                         argv_array_push(&cp->args, submodule_prefix.buf);
744                         ret = 1;
745                 }
746                 strbuf_release(&submodule_path);
747                 strbuf_release(&submodule_git_dir);
748                 strbuf_release(&submodule_prefix);
749                 if (ret) {
750                         spf->count++;
751                         return 1;
752                 }
753         }
754         return 0;
755 }
756
757 static int fetch_start_failure(struct strbuf *err,
758                                void *cb, void *task_cb)
759 {
760         struct submodule_parallel_fetch *spf = cb;
761
762         spf->result = 1;
763
764         return 0;
765 }
766
767 static int fetch_finish(int retvalue, struct strbuf *err,
768                         void *cb, void *task_cb)
769 {
770         struct submodule_parallel_fetch *spf = cb;
771
772         if (retvalue)
773                 spf->result = 1;
774
775         return 0;
776 }
777
778 int fetch_populated_submodules(const struct argv_array *options,
779                                const char *prefix, int command_line_option,
780                                int quiet, int max_parallel_jobs)
781 {
782         int i;
783         struct submodule_parallel_fetch spf = SPF_INIT;
784
785         spf.work_tree = get_git_work_tree();
786         spf.command_line_option = command_line_option;
787         spf.quiet = quiet;
788         spf.prefix = prefix;
789
790         if (!spf.work_tree)
791                 goto out;
792
793         if (read_cache() < 0)
794                 die("index file corrupt");
795
796         argv_array_push(&spf.args, "fetch");
797         for (i = 0; i < options->argc; i++)
798                 argv_array_push(&spf.args, options->argv[i]);
799         argv_array_push(&spf.args, "--recurse-submodules-default");
800         /* default value, "--submodule-prefix" and its value are added later */
801
802         if (max_parallel_jobs < 0)
803                 max_parallel_jobs = parallel_jobs;
804
805         calculate_changed_submodule_paths();
806         run_processes_parallel(max_parallel_jobs,
807                                get_next_submodule,
808                                fetch_start_failure,
809                                fetch_finish,
810                                &spf);
811
812         argv_array_clear(&spf.args);
813 out:
814         string_list_clear(&changed_submodule_paths, 1);
815         return spf.result;
816 }
817
818 unsigned is_submodule_modified(const char *path, int ignore_untracked)
819 {
820         ssize_t len;
821         struct child_process cp = CHILD_PROCESS_INIT;
822         const char *argv[] = {
823                 "status",
824                 "--porcelain",
825                 NULL,
826                 NULL,
827         };
828         struct strbuf buf = STRBUF_INIT;
829         unsigned dirty_submodule = 0;
830         const char *line, *next_line;
831         const char *git_dir;
832
833         strbuf_addf(&buf, "%s/.git", path);
834         git_dir = read_gitfile(buf.buf);
835         if (!git_dir)
836                 git_dir = buf.buf;
837         if (!is_directory(git_dir)) {
838                 strbuf_release(&buf);
839                 /* The submodule is not checked out, so it is not modified */
840                 return 0;
841
842         }
843         strbuf_reset(&buf);
844
845         if (ignore_untracked)
846                 argv[2] = "-uno";
847
848         cp.argv = argv;
849         prepare_submodule_repo_env(&cp.env_array);
850         cp.git_cmd = 1;
851         cp.no_stdin = 1;
852         cp.out = -1;
853         cp.dir = path;
854         if (start_command(&cp))
855                 die("Could not run 'git status --porcelain' in submodule %s", path);
856
857         len = strbuf_read(&buf, cp.out, 1024);
858         line = buf.buf;
859         while (len > 2) {
860                 if ((line[0] == '?') && (line[1] == '?')) {
861                         dirty_submodule |= DIRTY_SUBMODULE_UNTRACKED;
862                         if (dirty_submodule & DIRTY_SUBMODULE_MODIFIED)
863                                 break;
864                 } else {
865                         dirty_submodule |= DIRTY_SUBMODULE_MODIFIED;
866                         if (ignore_untracked ||
867                             (dirty_submodule & DIRTY_SUBMODULE_UNTRACKED))
868                                 break;
869                 }
870                 next_line = strchr(line, '\n');
871                 if (!next_line)
872                         break;
873                 next_line++;
874                 len -= (next_line - line);
875                 line = next_line;
876         }
877         close(cp.out);
878
879         if (finish_command(&cp))
880                 die("'git status --porcelain' failed in submodule %s", path);
881
882         strbuf_release(&buf);
883         return dirty_submodule;
884 }
885
886 int submodule_uses_gitfile(const char *path)
887 {
888         struct child_process cp = CHILD_PROCESS_INIT;
889         const char *argv[] = {
890                 "submodule",
891                 "foreach",
892                 "--quiet",
893                 "--recursive",
894                 "test -f .git",
895                 NULL,
896         };
897         struct strbuf buf = STRBUF_INIT;
898         const char *git_dir;
899
900         strbuf_addf(&buf, "%s/.git", path);
901         git_dir = read_gitfile(buf.buf);
902         if (!git_dir) {
903                 strbuf_release(&buf);
904                 return 0;
905         }
906         strbuf_release(&buf);
907
908         /* Now test that all nested submodules use a gitfile too */
909         cp.argv = argv;
910         prepare_submodule_repo_env(&cp.env_array);
911         cp.git_cmd = 1;
912         cp.no_stdin = 1;
913         cp.no_stderr = 1;
914         cp.no_stdout = 1;
915         cp.dir = path;
916         if (run_command(&cp))
917                 return 0;
918
919         return 1;
920 }
921
922 int ok_to_remove_submodule(const char *path)
923 {
924         ssize_t len;
925         struct child_process cp = CHILD_PROCESS_INIT;
926         const char *argv[] = {
927                 "status",
928                 "--porcelain",
929                 "-u",
930                 "--ignore-submodules=none",
931                 NULL,
932         };
933         struct strbuf buf = STRBUF_INIT;
934         int ok_to_remove = 1;
935
936         if (!file_exists(path) || is_empty_dir(path))
937                 return 1;
938
939         if (!submodule_uses_gitfile(path))
940                 return 0;
941
942         cp.argv = argv;
943         prepare_submodule_repo_env(&cp.env_array);
944         cp.git_cmd = 1;
945         cp.no_stdin = 1;
946         cp.out = -1;
947         cp.dir = path;
948         if (start_command(&cp))
949                 die("Could not run 'git status --porcelain -uall --ignore-submodules=none' in submodule %s", path);
950
951         len = strbuf_read(&buf, cp.out, 1024);
952         if (len > 2)
953                 ok_to_remove = 0;
954         close(cp.out);
955
956         if (finish_command(&cp))
957                 die("'git status --porcelain -uall --ignore-submodules=none' failed in submodule %s", path);
958
959         strbuf_release(&buf);
960         return ok_to_remove;
961 }
962
963 static int find_first_merges(struct object_array *result, const char *path,
964                 struct commit *a, struct commit *b)
965 {
966         int i, j;
967         struct object_array merges = OBJECT_ARRAY_INIT;
968         struct commit *commit;
969         int contains_another;
970
971         char merged_revision[42];
972         const char *rev_args[] = { "rev-list", "--merges", "--ancestry-path",
973                                    "--all", merged_revision, NULL };
974         struct rev_info revs;
975         struct setup_revision_opt rev_opts;
976
977         memset(result, 0, sizeof(struct object_array));
978         memset(&rev_opts, 0, sizeof(rev_opts));
979
980         /* get all revisions that merge commit a */
981         snprintf(merged_revision, sizeof(merged_revision), "^%s",
982                         oid_to_hex(&a->object.oid));
983         init_revisions(&revs, NULL);
984         rev_opts.submodule = path;
985         setup_revisions(ARRAY_SIZE(rev_args)-1, rev_args, &revs, &rev_opts);
986
987         /* save all revisions from the above list that contain b */
988         if (prepare_revision_walk(&revs))
989                 die("revision walk setup failed");
990         while ((commit = get_revision(&revs)) != NULL) {
991                 struct object *o = &(commit->object);
992                 if (in_merge_bases(b, commit))
993                         add_object_array(o, NULL, &merges);
994         }
995         reset_revision_walk();
996
997         /* Now we've got all merges that contain a and b. Prune all
998          * merges that contain another found merge and save them in
999          * result.
1000          */
1001         for (i = 0; i < merges.nr; i++) {
1002                 struct commit *m1 = (struct commit *) merges.objects[i].item;
1003
1004                 contains_another = 0;
1005                 for (j = 0; j < merges.nr; j++) {
1006                         struct commit *m2 = (struct commit *) merges.objects[j].item;
1007                         if (i != j && in_merge_bases(m2, m1)) {
1008                                 contains_another = 1;
1009                                 break;
1010                         }
1011                 }
1012
1013                 if (!contains_another)
1014                         add_object_array(merges.objects[i].item, NULL, result);
1015         }
1016
1017         free(merges.objects);
1018         return result->nr;
1019 }
1020
1021 static void print_commit(struct commit *commit)
1022 {
1023         struct strbuf sb = STRBUF_INIT;
1024         struct pretty_print_context ctx = {0};
1025         ctx.date_mode.type = DATE_NORMAL;
1026         format_commit_message(commit, " %h: %m %s", &sb, &ctx);
1027         fprintf(stderr, "%s\n", sb.buf);
1028         strbuf_release(&sb);
1029 }
1030
1031 #define MERGE_WARNING(path, msg) \
1032         warning("Failed to merge submodule %s (%s)", path, msg);
1033
1034 int merge_submodule(unsigned char result[20], const char *path,
1035                     const unsigned char base[20], const unsigned char a[20],
1036                     const unsigned char b[20], int search)
1037 {
1038         struct commit *commit_base, *commit_a, *commit_b;
1039         int parent_count;
1040         struct object_array merges;
1041
1042         int i;
1043
1044         /* store a in result in case we fail */
1045         hashcpy(result, a);
1046
1047         /* we can not handle deletion conflicts */
1048         if (is_null_sha1(base))
1049                 return 0;
1050         if (is_null_sha1(a))
1051                 return 0;
1052         if (is_null_sha1(b))
1053                 return 0;
1054
1055         if (add_submodule_odb(path)) {
1056                 MERGE_WARNING(path, "not checked out");
1057                 return 0;
1058         }
1059
1060         if (!(commit_base = lookup_commit_reference(base)) ||
1061             !(commit_a = lookup_commit_reference(a)) ||
1062             !(commit_b = lookup_commit_reference(b))) {
1063                 MERGE_WARNING(path, "commits not present");
1064                 return 0;
1065         }
1066
1067         /* check whether both changes are forward */
1068         if (!in_merge_bases(commit_base, commit_a) ||
1069             !in_merge_bases(commit_base, commit_b)) {
1070                 MERGE_WARNING(path, "commits don't follow merge-base");
1071                 return 0;
1072         }
1073
1074         /* Case #1: a is contained in b or vice versa */
1075         if (in_merge_bases(commit_a, commit_b)) {
1076                 hashcpy(result, b);
1077                 return 1;
1078         }
1079         if (in_merge_bases(commit_b, commit_a)) {
1080                 hashcpy(result, a);
1081                 return 1;
1082         }
1083
1084         /*
1085          * Case #2: There are one or more merges that contain a and b in
1086          * the submodule. If there is only one, then present it as a
1087          * suggestion to the user, but leave it marked unmerged so the
1088          * user needs to confirm the resolution.
1089          */
1090
1091         /* Skip the search if makes no sense to the calling context.  */
1092         if (!search)
1093                 return 0;
1094
1095         /* find commit which merges them */
1096         parent_count = find_first_merges(&merges, path, commit_a, commit_b);
1097         switch (parent_count) {
1098         case 0:
1099                 MERGE_WARNING(path, "merge following commits not found");
1100                 break;
1101
1102         case 1:
1103                 MERGE_WARNING(path, "not fast-forward");
1104                 fprintf(stderr, "Found a possible merge resolution "
1105                                 "for the submodule:\n");
1106                 print_commit((struct commit *) merges.objects[0].item);
1107                 fprintf(stderr,
1108                         "If this is correct simply add it to the index "
1109                         "for example\n"
1110                         "by using:\n\n"
1111                         "  git update-index --cacheinfo 160000 %s \"%s\"\n\n"
1112                         "which will accept this suggestion.\n",
1113                         oid_to_hex(&merges.objects[0].item->oid), path);
1114                 break;
1115
1116         default:
1117                 MERGE_WARNING(path, "multiple merges found");
1118                 for (i = 0; i < merges.nr; i++)
1119                         print_commit((struct commit *) merges.objects[i].item);
1120         }
1121
1122         free(merges.objects);
1123         return 0;
1124 }
1125
1126 /* Update gitfile and core.worktree setting to connect work tree and git dir */
1127 void connect_work_tree_and_git_dir(const char *work_tree, const char *git_dir)
1128 {
1129         struct strbuf file_name = STRBUF_INIT;
1130         struct strbuf rel_path = STRBUF_INIT;
1131         const char *real_work_tree = xstrdup(real_path(work_tree));
1132
1133         /* Update gitfile */
1134         strbuf_addf(&file_name, "%s/.git", work_tree);
1135         write_file(file_name.buf, "gitdir: %s",
1136                    relative_path(git_dir, real_work_tree, &rel_path));
1137
1138         /* Update core.worktree setting */
1139         strbuf_reset(&file_name);
1140         strbuf_addf(&file_name, "%s/config", git_dir);
1141         git_config_set_in_file(file_name.buf, "core.worktree",
1142                                relative_path(real_work_tree, git_dir,
1143                                              &rel_path));
1144
1145         strbuf_release(&file_name);
1146         strbuf_release(&rel_path);
1147         free((void *)real_work_tree);
1148 }
1149
1150 int parallel_submodules(void)
1151 {
1152         return parallel_jobs;
1153 }
1154
1155 void prepare_submodule_repo_env(struct argv_array *out)
1156 {
1157         const char * const *var;
1158
1159         for (var = local_repo_env; *var; var++) {
1160                 if (strcmp(*var, CONFIG_DATA_ENVIRONMENT))
1161                         argv_array_push(out, *var);
1162         }
1163 }