Merge branch 'jc/cocci-xstrdup-or-null' into maint
[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 ", line_prefix, meta, path);
374         strbuf_add_unique_abbrev(&sb, one, DEFAULT_ABBREV);
375         strbuf_addstr(&sb, (fast_backward || fast_forward) ? ".." : "...");
376         strbuf_add_unique_abbrev(&sb, two, DEFAULT_ABBREV);
377         if (message)
378                 strbuf_addf(&sb, " %s%s\n", message, reset);
379         else
380                 strbuf_addf(&sb, "%s:%s\n", fast_backward ? " (rewind)" : "", reset);
381         fwrite(sb.buf, sb.len, 1, f);
382
383         if (!message) /* only NULL if we succeeded in setting up the walk */
384                 print_submodule_summary(&rev, f, line_prefix, del, add, reset);
385         if (left)
386                 clear_commit_marks(left, ~0);
387         if (right)
388                 clear_commit_marks(right, ~0);
389
390         strbuf_release(&sb);
391 }
392
393 void set_config_fetch_recurse_submodules(int value)
394 {
395         config_fetch_recurse_submodules = value;
396 }
397
398 static int has_remote(const char *refname, const struct object_id *oid,
399                       int flags, void *cb_data)
400 {
401         return 1;
402 }
403
404 static int submodule_needs_pushing(const char *path, const unsigned char sha1[20])
405 {
406         if (add_submodule_odb(path) || !lookup_commit_reference(sha1))
407                 return 0;
408
409         if (for_each_remote_ref_submodule(path, has_remote, NULL) > 0) {
410                 struct child_process cp = CHILD_PROCESS_INIT;
411                 const char *argv[] = {"rev-list", NULL, "--not", "--remotes", "-n", "1" , NULL};
412                 struct strbuf buf = STRBUF_INIT;
413                 int needs_pushing = 0;
414
415                 argv[1] = sha1_to_hex(sha1);
416                 cp.argv = argv;
417                 prepare_submodule_repo_env(&cp.env_array);
418                 cp.git_cmd = 1;
419                 cp.no_stdin = 1;
420                 cp.out = -1;
421                 cp.dir = path;
422                 if (start_command(&cp))
423                         die("Could not run 'git rev-list %s --not --remotes -n 1' command in submodule %s",
424                                 sha1_to_hex(sha1), path);
425                 if (strbuf_read(&buf, cp.out, 41))
426                         needs_pushing = 1;
427                 finish_command(&cp);
428                 close(cp.out);
429                 strbuf_release(&buf);
430                 return needs_pushing;
431         }
432
433         return 0;
434 }
435
436 static void collect_submodules_from_diff(struct diff_queue_struct *q,
437                                          struct diff_options *options,
438                                          void *data)
439 {
440         int i;
441         struct string_list *needs_pushing = data;
442
443         for (i = 0; i < q->nr; i++) {
444                 struct diff_filepair *p = q->queue[i];
445                 if (!S_ISGITLINK(p->two->mode))
446                         continue;
447                 if (submodule_needs_pushing(p->two->path, p->two->oid.hash))
448                         string_list_insert(needs_pushing, p->two->path);
449         }
450 }
451
452 static void find_unpushed_submodule_commits(struct commit *commit,
453                 struct string_list *needs_pushing)
454 {
455         struct rev_info rev;
456
457         init_revisions(&rev, NULL);
458         rev.diffopt.output_format |= DIFF_FORMAT_CALLBACK;
459         rev.diffopt.format_callback = collect_submodules_from_diff;
460         rev.diffopt.format_callback_data = needs_pushing;
461         diff_tree_combined_merge(commit, 1, &rev);
462 }
463
464 int find_unpushed_submodules(unsigned char new_sha1[20],
465                 const char *remotes_name, struct string_list *needs_pushing)
466 {
467         struct rev_info rev;
468         struct commit *commit;
469         const char *argv[] = {NULL, NULL, "--not", "NULL", NULL};
470         int argc = ARRAY_SIZE(argv) - 1;
471         char *sha1_copy;
472
473         struct strbuf remotes_arg = STRBUF_INIT;
474
475         strbuf_addf(&remotes_arg, "--remotes=%s", remotes_name);
476         init_revisions(&rev, NULL);
477         sha1_copy = xstrdup(sha1_to_hex(new_sha1));
478         argv[1] = sha1_copy;
479         argv[3] = remotes_arg.buf;
480         setup_revisions(argc, argv, &rev, NULL);
481         if (prepare_revision_walk(&rev))
482                 die("revision walk setup failed");
483
484         while ((commit = get_revision(&rev)) != NULL)
485                 find_unpushed_submodule_commits(commit, needs_pushing);
486
487         reset_revision_walk();
488         free(sha1_copy);
489         strbuf_release(&remotes_arg);
490
491         return needs_pushing->nr;
492 }
493
494 static int push_submodule(const char *path)
495 {
496         if (add_submodule_odb(path))
497                 return 1;
498
499         if (for_each_remote_ref_submodule(path, has_remote, NULL) > 0) {
500                 struct child_process cp = CHILD_PROCESS_INIT;
501                 const char *argv[] = {"push", NULL};
502
503                 cp.argv = argv;
504                 prepare_submodule_repo_env(&cp.env_array);
505                 cp.git_cmd = 1;
506                 cp.no_stdin = 1;
507                 cp.dir = path;
508                 if (run_command(&cp))
509                         return 0;
510                 close(cp.out);
511         }
512
513         return 1;
514 }
515
516 int push_unpushed_submodules(unsigned char new_sha1[20], const char *remotes_name)
517 {
518         int i, ret = 1;
519         struct string_list needs_pushing = STRING_LIST_INIT_DUP;
520
521         if (!find_unpushed_submodules(new_sha1, remotes_name, &needs_pushing))
522                 return 1;
523
524         for (i = 0; i < needs_pushing.nr; i++) {
525                 const char *path = needs_pushing.items[i].string;
526                 fprintf(stderr, "Pushing submodule '%s'\n", path);
527                 if (!push_submodule(path)) {
528                         fprintf(stderr, "Unable to push submodule '%s'\n", path);
529                         ret = 0;
530                 }
531         }
532
533         string_list_clear(&needs_pushing, 0);
534
535         return ret;
536 }
537
538 static int is_submodule_commit_present(const char *path, unsigned char sha1[20])
539 {
540         int is_present = 0;
541         if (!add_submodule_odb(path) && lookup_commit_reference(sha1)) {
542                 /* Even if the submodule is checked out and the commit is
543                  * present, make sure it is reachable from a ref. */
544                 struct child_process cp = CHILD_PROCESS_INIT;
545                 const char *argv[] = {"rev-list", "-n", "1", NULL, "--not", "--all", NULL};
546                 struct strbuf buf = STRBUF_INIT;
547
548                 argv[3] = sha1_to_hex(sha1);
549                 cp.argv = argv;
550                 prepare_submodule_repo_env(&cp.env_array);
551                 cp.git_cmd = 1;
552                 cp.no_stdin = 1;
553                 cp.dir = path;
554                 if (!capture_command(&cp, &buf, 1024) && !buf.len)
555                         is_present = 1;
556
557                 strbuf_release(&buf);
558         }
559         return is_present;
560 }
561
562 static void submodule_collect_changed_cb(struct diff_queue_struct *q,
563                                          struct diff_options *options,
564                                          void *data)
565 {
566         int i;
567         for (i = 0; i < q->nr; i++) {
568                 struct diff_filepair *p = q->queue[i];
569                 if (!S_ISGITLINK(p->two->mode))
570                         continue;
571
572                 if (S_ISGITLINK(p->one->mode)) {
573                         /* NEEDSWORK: We should honor the name configured in
574                          * the .gitmodules file of the commit we are examining
575                          * here to be able to correctly follow submodules
576                          * being moved around. */
577                         struct string_list_item *path;
578                         path = unsorted_string_list_lookup(&changed_submodule_paths, p->two->path);
579                         if (!path && !is_submodule_commit_present(p->two->path, p->two->oid.hash))
580                                 string_list_append(&changed_submodule_paths, xstrdup(p->two->path));
581                 } else {
582                         /* Submodule is new or was moved here */
583                         /* NEEDSWORK: When the .git directories of submodules
584                          * live inside the superprojects .git directory some
585                          * day we should fetch new submodules directly into
586                          * that location too when config or options request
587                          * that so they can be checked out from there. */
588                         continue;
589                 }
590         }
591 }
592
593 static int add_sha1_to_array(const char *ref, const struct object_id *oid,
594                              int flags, void *data)
595 {
596         sha1_array_append(data, oid->hash);
597         return 0;
598 }
599
600 void check_for_new_submodule_commits(unsigned char new_sha1[20])
601 {
602         if (!initialized_fetch_ref_tips) {
603                 for_each_ref(add_sha1_to_array, &ref_tips_before_fetch);
604                 initialized_fetch_ref_tips = 1;
605         }
606
607         sha1_array_append(&ref_tips_after_fetch, new_sha1);
608 }
609
610 static void add_sha1_to_argv(const unsigned char sha1[20], void *data)
611 {
612         argv_array_push(data, sha1_to_hex(sha1));
613 }
614
615 static void calculate_changed_submodule_paths(void)
616 {
617         struct rev_info rev;
618         struct commit *commit;
619         struct argv_array argv = ARGV_ARRAY_INIT;
620
621         /* No need to check if there are no submodules configured */
622         if (!submodule_from_path(NULL, NULL))
623                 return;
624
625         init_revisions(&rev, NULL);
626         argv_array_push(&argv, "--"); /* argv[0] program name */
627         sha1_array_for_each_unique(&ref_tips_after_fetch,
628                                    add_sha1_to_argv, &argv);
629         argv_array_push(&argv, "--not");
630         sha1_array_for_each_unique(&ref_tips_before_fetch,
631                                    add_sha1_to_argv, &argv);
632         setup_revisions(argv.argc, argv.argv, &rev, NULL);
633         if (prepare_revision_walk(&rev))
634                 die("revision walk setup failed");
635
636         /*
637          * Collect all submodules (whether checked out or not) for which new
638          * commits have been recorded upstream in "changed_submodule_paths".
639          */
640         while ((commit = get_revision(&rev))) {
641                 struct commit_list *parent = commit->parents;
642                 while (parent) {
643                         struct diff_options diff_opts;
644                         diff_setup(&diff_opts);
645                         DIFF_OPT_SET(&diff_opts, RECURSIVE);
646                         diff_opts.output_format |= DIFF_FORMAT_CALLBACK;
647                         diff_opts.format_callback = submodule_collect_changed_cb;
648                         diff_setup_done(&diff_opts);
649                         diff_tree_sha1(parent->item->object.oid.hash, commit->object.oid.hash, "", &diff_opts);
650                         diffcore_std(&diff_opts);
651                         diff_flush(&diff_opts);
652                         parent = parent->next;
653                 }
654         }
655
656         argv_array_clear(&argv);
657         sha1_array_clear(&ref_tips_before_fetch);
658         sha1_array_clear(&ref_tips_after_fetch);
659         initialized_fetch_ref_tips = 0;
660 }
661
662 struct submodule_parallel_fetch {
663         int count;
664         struct argv_array args;
665         const char *work_tree;
666         const char *prefix;
667         int command_line_option;
668         int quiet;
669         int result;
670 };
671 #define SPF_INIT {0, ARGV_ARRAY_INIT, NULL, NULL, 0, 0, 0}
672
673 static int get_next_submodule(struct child_process *cp,
674                               struct strbuf *err, void *data, void **task_cb)
675 {
676         int ret = 0;
677         struct submodule_parallel_fetch *spf = data;
678
679         for (; spf->count < active_nr; spf->count++) {
680                 struct strbuf submodule_path = STRBUF_INIT;
681                 struct strbuf submodule_git_dir = STRBUF_INIT;
682                 struct strbuf submodule_prefix = STRBUF_INIT;
683                 const struct cache_entry *ce = active_cache[spf->count];
684                 const char *git_dir, *default_argv;
685                 const struct submodule *submodule;
686
687                 if (!S_ISGITLINK(ce->ce_mode))
688                         continue;
689
690                 submodule = submodule_from_path(null_sha1, ce->name);
691                 if (!submodule)
692                         submodule = submodule_from_name(null_sha1, ce->name);
693
694                 default_argv = "yes";
695                 if (spf->command_line_option == RECURSE_SUBMODULES_DEFAULT) {
696                         if (submodule &&
697                             submodule->fetch_recurse !=
698                                                 RECURSE_SUBMODULES_NONE) {
699                                 if (submodule->fetch_recurse ==
700                                                 RECURSE_SUBMODULES_OFF)
701                                         continue;
702                                 if (submodule->fetch_recurse ==
703                                                 RECURSE_SUBMODULES_ON_DEMAND) {
704                                         if (!unsorted_string_list_lookup(&changed_submodule_paths, ce->name))
705                                                 continue;
706                                         default_argv = "on-demand";
707                                 }
708                         } else {
709                                 if ((config_fetch_recurse_submodules == RECURSE_SUBMODULES_OFF) ||
710                                     gitmodules_is_unmerged)
711                                         continue;
712                                 if (config_fetch_recurse_submodules == RECURSE_SUBMODULES_ON_DEMAND) {
713                                         if (!unsorted_string_list_lookup(&changed_submodule_paths, ce->name))
714                                                 continue;
715                                         default_argv = "on-demand";
716                                 }
717                         }
718                 } else if (spf->command_line_option == RECURSE_SUBMODULES_ON_DEMAND) {
719                         if (!unsorted_string_list_lookup(&changed_submodule_paths, ce->name))
720                                 continue;
721                         default_argv = "on-demand";
722                 }
723
724                 strbuf_addf(&submodule_path, "%s/%s", spf->work_tree, ce->name);
725                 strbuf_addf(&submodule_git_dir, "%s/.git", submodule_path.buf);
726                 strbuf_addf(&submodule_prefix, "%s%s/", spf->prefix, ce->name);
727                 git_dir = read_gitfile(submodule_git_dir.buf);
728                 if (!git_dir)
729                         git_dir = submodule_git_dir.buf;
730                 if (is_directory(git_dir)) {
731                         child_process_init(cp);
732                         cp->dir = strbuf_detach(&submodule_path, NULL);
733                         prepare_submodule_repo_env(&cp->env_array);
734                         cp->git_cmd = 1;
735                         if (!spf->quiet)
736                                 strbuf_addf(err, "Fetching submodule %s%s\n",
737                                             spf->prefix, ce->name);
738                         argv_array_init(&cp->args);
739                         argv_array_pushv(&cp->args, spf->args.argv);
740                         argv_array_push(&cp->args, default_argv);
741                         argv_array_push(&cp->args, "--submodule-prefix");
742                         argv_array_push(&cp->args, submodule_prefix.buf);
743                         ret = 1;
744                 }
745                 strbuf_release(&submodule_path);
746                 strbuf_release(&submodule_git_dir);
747                 strbuf_release(&submodule_prefix);
748                 if (ret) {
749                         spf->count++;
750                         return 1;
751                 }
752         }
753         return 0;
754 }
755
756 static int fetch_start_failure(struct strbuf *err,
757                                void *cb, void *task_cb)
758 {
759         struct submodule_parallel_fetch *spf = cb;
760
761         spf->result = 1;
762
763         return 0;
764 }
765
766 static int fetch_finish(int retvalue, struct strbuf *err,
767                         void *cb, void *task_cb)
768 {
769         struct submodule_parallel_fetch *spf = cb;
770
771         if (retvalue)
772                 spf->result = 1;
773
774         return 0;
775 }
776
777 int fetch_populated_submodules(const struct argv_array *options,
778                                const char *prefix, int command_line_option,
779                                int quiet, int max_parallel_jobs)
780 {
781         int i;
782         struct submodule_parallel_fetch spf = SPF_INIT;
783
784         spf.work_tree = get_git_work_tree();
785         spf.command_line_option = command_line_option;
786         spf.quiet = quiet;
787         spf.prefix = prefix;
788
789         if (!spf.work_tree)
790                 goto out;
791
792         if (read_cache() < 0)
793                 die("index file corrupt");
794
795         argv_array_push(&spf.args, "fetch");
796         for (i = 0; i < options->argc; i++)
797                 argv_array_push(&spf.args, options->argv[i]);
798         argv_array_push(&spf.args, "--recurse-submodules-default");
799         /* default value, "--submodule-prefix" and its value are added later */
800
801         if (max_parallel_jobs < 0)
802                 max_parallel_jobs = parallel_jobs;
803
804         calculate_changed_submodule_paths();
805         run_processes_parallel(max_parallel_jobs,
806                                get_next_submodule,
807                                fetch_start_failure,
808                                fetch_finish,
809                                &spf);
810
811         argv_array_clear(&spf.args);
812 out:
813         string_list_clear(&changed_submodule_paths, 1);
814         return spf.result;
815 }
816
817 unsigned is_submodule_modified(const char *path, int ignore_untracked)
818 {
819         ssize_t len;
820         struct child_process cp = CHILD_PROCESS_INIT;
821         const char *argv[] = {
822                 "status",
823                 "--porcelain",
824                 NULL,
825                 NULL,
826         };
827         struct strbuf buf = STRBUF_INIT;
828         unsigned dirty_submodule = 0;
829         const char *line, *next_line;
830         const char *git_dir;
831
832         strbuf_addf(&buf, "%s/.git", path);
833         git_dir = read_gitfile(buf.buf);
834         if (!git_dir)
835                 git_dir = buf.buf;
836         if (!is_directory(git_dir)) {
837                 strbuf_release(&buf);
838                 /* The submodule is not checked out, so it is not modified */
839                 return 0;
840
841         }
842         strbuf_reset(&buf);
843
844         if (ignore_untracked)
845                 argv[2] = "-uno";
846
847         cp.argv = argv;
848         prepare_submodule_repo_env(&cp.env_array);
849         cp.git_cmd = 1;
850         cp.no_stdin = 1;
851         cp.out = -1;
852         cp.dir = path;
853         if (start_command(&cp))
854                 die("Could not run 'git status --porcelain' in submodule %s", path);
855
856         len = strbuf_read(&buf, cp.out, 1024);
857         line = buf.buf;
858         while (len > 2) {
859                 if ((line[0] == '?') && (line[1] == '?')) {
860                         dirty_submodule |= DIRTY_SUBMODULE_UNTRACKED;
861                         if (dirty_submodule & DIRTY_SUBMODULE_MODIFIED)
862                                 break;
863                 } else {
864                         dirty_submodule |= DIRTY_SUBMODULE_MODIFIED;
865                         if (ignore_untracked ||
866                             (dirty_submodule & DIRTY_SUBMODULE_UNTRACKED))
867                                 break;
868                 }
869                 next_line = strchr(line, '\n');
870                 if (!next_line)
871                         break;
872                 next_line++;
873                 len -= (next_line - line);
874                 line = next_line;
875         }
876         close(cp.out);
877
878         if (finish_command(&cp))
879                 die("'git status --porcelain' failed in submodule %s", path);
880
881         strbuf_release(&buf);
882         return dirty_submodule;
883 }
884
885 int submodule_uses_gitfile(const char *path)
886 {
887         struct child_process cp = CHILD_PROCESS_INIT;
888         const char *argv[] = {
889                 "submodule",
890                 "foreach",
891                 "--quiet",
892                 "--recursive",
893                 "test -f .git",
894                 NULL,
895         };
896         struct strbuf buf = STRBUF_INIT;
897         const char *git_dir;
898
899         strbuf_addf(&buf, "%s/.git", path);
900         git_dir = read_gitfile(buf.buf);
901         if (!git_dir) {
902                 strbuf_release(&buf);
903                 return 0;
904         }
905         strbuf_release(&buf);
906
907         /* Now test that all nested submodules use a gitfile too */
908         cp.argv = argv;
909         prepare_submodule_repo_env(&cp.env_array);
910         cp.git_cmd = 1;
911         cp.no_stdin = 1;
912         cp.no_stderr = 1;
913         cp.no_stdout = 1;
914         cp.dir = path;
915         if (run_command(&cp))
916                 return 0;
917
918         return 1;
919 }
920
921 int ok_to_remove_submodule(const char *path)
922 {
923         ssize_t len;
924         struct child_process cp = CHILD_PROCESS_INIT;
925         const char *argv[] = {
926                 "status",
927                 "--porcelain",
928                 "-u",
929                 "--ignore-submodules=none",
930                 NULL,
931         };
932         struct strbuf buf = STRBUF_INIT;
933         int ok_to_remove = 1;
934
935         if (!file_exists(path) || is_empty_dir(path))
936                 return 1;
937
938         if (!submodule_uses_gitfile(path))
939                 return 0;
940
941         cp.argv = argv;
942         prepare_submodule_repo_env(&cp.env_array);
943         cp.git_cmd = 1;
944         cp.no_stdin = 1;
945         cp.out = -1;
946         cp.dir = path;
947         if (start_command(&cp))
948                 die("Could not run 'git status --porcelain -uall --ignore-submodules=none' in submodule %s", path);
949
950         len = strbuf_read(&buf, cp.out, 1024);
951         if (len > 2)
952                 ok_to_remove = 0;
953         close(cp.out);
954
955         if (finish_command(&cp))
956                 die("'git status --porcelain -uall --ignore-submodules=none' failed in submodule %s", path);
957
958         strbuf_release(&buf);
959         return ok_to_remove;
960 }
961
962 static int find_first_merges(struct object_array *result, const char *path,
963                 struct commit *a, struct commit *b)
964 {
965         int i, j;
966         struct object_array merges = OBJECT_ARRAY_INIT;
967         struct commit *commit;
968         int contains_another;
969
970         char merged_revision[42];
971         const char *rev_args[] = { "rev-list", "--merges", "--ancestry-path",
972                                    "--all", merged_revision, NULL };
973         struct rev_info revs;
974         struct setup_revision_opt rev_opts;
975
976         memset(result, 0, sizeof(struct object_array));
977         memset(&rev_opts, 0, sizeof(rev_opts));
978
979         /* get all revisions that merge commit a */
980         snprintf(merged_revision, sizeof(merged_revision), "^%s",
981                         oid_to_hex(&a->object.oid));
982         init_revisions(&revs, NULL);
983         rev_opts.submodule = path;
984         setup_revisions(ARRAY_SIZE(rev_args)-1, rev_args, &revs, &rev_opts);
985
986         /* save all revisions from the above list that contain b */
987         if (prepare_revision_walk(&revs))
988                 die("revision walk setup failed");
989         while ((commit = get_revision(&revs)) != NULL) {
990                 struct object *o = &(commit->object);
991                 if (in_merge_bases(b, commit))
992                         add_object_array(o, NULL, &merges);
993         }
994         reset_revision_walk();
995
996         /* Now we've got all merges that contain a and b. Prune all
997          * merges that contain another found merge and save them in
998          * result.
999          */
1000         for (i = 0; i < merges.nr; i++) {
1001                 struct commit *m1 = (struct commit *) merges.objects[i].item;
1002
1003                 contains_another = 0;
1004                 for (j = 0; j < merges.nr; j++) {
1005                         struct commit *m2 = (struct commit *) merges.objects[j].item;
1006                         if (i != j && in_merge_bases(m2, m1)) {
1007                                 contains_another = 1;
1008                                 break;
1009                         }
1010                 }
1011
1012                 if (!contains_another)
1013                         add_object_array(merges.objects[i].item, NULL, result);
1014         }
1015
1016         free(merges.objects);
1017         return result->nr;
1018 }
1019
1020 static void print_commit(struct commit *commit)
1021 {
1022         struct strbuf sb = STRBUF_INIT;
1023         struct pretty_print_context ctx = {0};
1024         ctx.date_mode.type = DATE_NORMAL;
1025         format_commit_message(commit, " %h: %m %s", &sb, &ctx);
1026         fprintf(stderr, "%s\n", sb.buf);
1027         strbuf_release(&sb);
1028 }
1029
1030 #define MERGE_WARNING(path, msg) \
1031         warning("Failed to merge submodule %s (%s)", path, msg);
1032
1033 int merge_submodule(unsigned char result[20], const char *path,
1034                     const unsigned char base[20], const unsigned char a[20],
1035                     const unsigned char b[20], int search)
1036 {
1037         struct commit *commit_base, *commit_a, *commit_b;
1038         int parent_count;
1039         struct object_array merges;
1040
1041         int i;
1042
1043         /* store a in result in case we fail */
1044         hashcpy(result, a);
1045
1046         /* we can not handle deletion conflicts */
1047         if (is_null_sha1(base))
1048                 return 0;
1049         if (is_null_sha1(a))
1050                 return 0;
1051         if (is_null_sha1(b))
1052                 return 0;
1053
1054         if (add_submodule_odb(path)) {
1055                 MERGE_WARNING(path, "not checked out");
1056                 return 0;
1057         }
1058
1059         if (!(commit_base = lookup_commit_reference(base)) ||
1060             !(commit_a = lookup_commit_reference(a)) ||
1061             !(commit_b = lookup_commit_reference(b))) {
1062                 MERGE_WARNING(path, "commits not present");
1063                 return 0;
1064         }
1065
1066         /* check whether both changes are forward */
1067         if (!in_merge_bases(commit_base, commit_a) ||
1068             !in_merge_bases(commit_base, commit_b)) {
1069                 MERGE_WARNING(path, "commits don't follow merge-base");
1070                 return 0;
1071         }
1072
1073         /* Case #1: a is contained in b or vice versa */
1074         if (in_merge_bases(commit_a, commit_b)) {
1075                 hashcpy(result, b);
1076                 return 1;
1077         }
1078         if (in_merge_bases(commit_b, commit_a)) {
1079                 hashcpy(result, a);
1080                 return 1;
1081         }
1082
1083         /*
1084          * Case #2: There are one or more merges that contain a and b in
1085          * the submodule. If there is only one, then present it as a
1086          * suggestion to the user, but leave it marked unmerged so the
1087          * user needs to confirm the resolution.
1088          */
1089
1090         /* Skip the search if makes no sense to the calling context.  */
1091         if (!search)
1092                 return 0;
1093
1094         /* find commit which merges them */
1095         parent_count = find_first_merges(&merges, path, commit_a, commit_b);
1096         switch (parent_count) {
1097         case 0:
1098                 MERGE_WARNING(path, "merge following commits not found");
1099                 break;
1100
1101         case 1:
1102                 MERGE_WARNING(path, "not fast-forward");
1103                 fprintf(stderr, "Found a possible merge resolution "
1104                                 "for the submodule:\n");
1105                 print_commit((struct commit *) merges.objects[0].item);
1106                 fprintf(stderr,
1107                         "If this is correct simply add it to the index "
1108                         "for example\n"
1109                         "by using:\n\n"
1110                         "  git update-index --cacheinfo 160000 %s \"%s\"\n\n"
1111                         "which will accept this suggestion.\n",
1112                         oid_to_hex(&merges.objects[0].item->oid), path);
1113                 break;
1114
1115         default:
1116                 MERGE_WARNING(path, "multiple merges found");
1117                 for (i = 0; i < merges.nr; i++)
1118                         print_commit((struct commit *) merges.objects[i].item);
1119         }
1120
1121         free(merges.objects);
1122         return 0;
1123 }
1124
1125 /* Update gitfile and core.worktree setting to connect work tree and git dir */
1126 void connect_work_tree_and_git_dir(const char *work_tree, const char *git_dir)
1127 {
1128         struct strbuf file_name = STRBUF_INIT;
1129         struct strbuf rel_path = STRBUF_INIT;
1130         const char *real_work_tree = xstrdup(real_path(work_tree));
1131
1132         /* Update gitfile */
1133         strbuf_addf(&file_name, "%s/.git", work_tree);
1134         write_file(file_name.buf, "gitdir: %s",
1135                    relative_path(git_dir, real_work_tree, &rel_path));
1136
1137         /* Update core.worktree setting */
1138         strbuf_reset(&file_name);
1139         strbuf_addf(&file_name, "%s/config", git_dir);
1140         git_config_set_in_file(file_name.buf, "core.worktree",
1141                                relative_path(real_work_tree, git_dir,
1142                                              &rel_path));
1143
1144         strbuf_release(&file_name);
1145         strbuf_release(&rel_path);
1146         free((void *)real_work_tree);
1147 }
1148
1149 int parallel_submodules(void)
1150 {
1151         return parallel_jobs;
1152 }
1153
1154 void prepare_submodule_repo_env(struct argv_array *out)
1155 {
1156         const char * const *var;
1157
1158         for (var = local_repo_env; *var; var++) {
1159                 if (strcmp(*var, CONFIG_DATA_ENVIRONMENT))
1160                         argv_array_push(out, *var);
1161         }
1162         argv_array_push(out, "GIT_DIR=.git");
1163 }