Merge branch 'rs/cocci'
[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         int ret = 0;
127
128         ret = strbuf_git_path_submodule(&objects_directory, path, "objects/");
129         if (ret)
130                 goto done;
131         if (!is_directory(objects_directory.buf)) {
132                 ret = -1;
133                 goto done;
134         }
135         add_to_alternates_memory(objects_directory.buf);
136 done:
137         strbuf_release(&objects_directory);
138         return ret;
139 }
140
141 void set_diffopt_flags_from_submodule_config(struct diff_options *diffopt,
142                                              const char *path)
143 {
144         const struct submodule *submodule = submodule_from_path(null_sha1, path);
145         if (submodule) {
146                 if (submodule->ignore)
147                         handle_ignore_submodules_arg(diffopt, submodule->ignore);
148                 else if (gitmodules_is_unmerged)
149                         DIFF_OPT_SET(diffopt, IGNORE_SUBMODULES);
150         }
151 }
152
153 int submodule_config(const char *var, const char *value, void *cb)
154 {
155         if (!strcmp(var, "submodule.fetchjobs")) {
156                 parallel_jobs = git_config_int(var, value);
157                 if (parallel_jobs < 0)
158                         die(_("negative values not allowed for submodule.fetchJobs"));
159                 return 0;
160         } else if (starts_with(var, "submodule."))
161                 return parse_submodule_config_option(var, value);
162         else if (!strcmp(var, "fetch.recursesubmodules")) {
163                 config_fetch_recurse_submodules = parse_fetch_recurse_submodules_arg(var, value);
164                 return 0;
165         }
166         return 0;
167 }
168
169 void gitmodules_config(void)
170 {
171         const char *work_tree = get_git_work_tree();
172         if (work_tree) {
173                 struct strbuf gitmodules_path = STRBUF_INIT;
174                 int pos;
175                 strbuf_addstr(&gitmodules_path, work_tree);
176                 strbuf_addstr(&gitmodules_path, "/.gitmodules");
177                 if (read_cache() < 0)
178                         die("index file corrupt");
179                 pos = cache_name_pos(".gitmodules", 11);
180                 if (pos < 0) { /* .gitmodules not found or isn't merged */
181                         pos = -1 - pos;
182                         if (active_nr > pos) {  /* there is a .gitmodules */
183                                 const struct cache_entry *ce = active_cache[pos];
184                                 if (ce_namelen(ce) == 11 &&
185                                     !memcmp(ce->name, ".gitmodules", 11))
186                                         gitmodules_is_unmerged = 1;
187                         }
188                 } else if (pos < active_nr) {
189                         struct stat st;
190                         if (lstat(".gitmodules", &st) == 0 &&
191                             ce_match_stat(active_cache[pos], &st, 0) & DATA_CHANGED)
192                                 gitmodules_is_modified = 1;
193                 }
194
195                 if (!gitmodules_is_unmerged)
196                         git_config_from_file(submodule_config, gitmodules_path.buf, NULL);
197                 strbuf_release(&gitmodules_path);
198         }
199 }
200
201 int parse_submodule_update_strategy(const char *value,
202                 struct submodule_update_strategy *dst)
203 {
204         free((void*)dst->command);
205         dst->command = NULL;
206         if (!strcmp(value, "none"))
207                 dst->type = SM_UPDATE_NONE;
208         else if (!strcmp(value, "checkout"))
209                 dst->type = SM_UPDATE_CHECKOUT;
210         else if (!strcmp(value, "rebase"))
211                 dst->type = SM_UPDATE_REBASE;
212         else if (!strcmp(value, "merge"))
213                 dst->type = SM_UPDATE_MERGE;
214         else if (skip_prefix(value, "!", &value)) {
215                 dst->type = SM_UPDATE_COMMAND;
216                 dst->command = xstrdup(value);
217         } else
218                 return -1;
219         return 0;
220 }
221
222 const char *submodule_strategy_to_string(const struct submodule_update_strategy *s)
223 {
224         struct strbuf sb = STRBUF_INIT;
225         switch (s->type) {
226         case SM_UPDATE_CHECKOUT:
227                 return "checkout";
228         case SM_UPDATE_MERGE:
229                 return "merge";
230         case SM_UPDATE_REBASE:
231                 return "rebase";
232         case SM_UPDATE_NONE:
233                 return "none";
234         case SM_UPDATE_UNSPECIFIED:
235                 return NULL;
236         case SM_UPDATE_COMMAND:
237                 strbuf_addf(&sb, "!%s", s->command);
238                 return strbuf_detach(&sb, NULL);
239         }
240         return NULL;
241 }
242
243 void handle_ignore_submodules_arg(struct diff_options *diffopt,
244                                   const char *arg)
245 {
246         DIFF_OPT_CLR(diffopt, IGNORE_SUBMODULES);
247         DIFF_OPT_CLR(diffopt, IGNORE_UNTRACKED_IN_SUBMODULES);
248         DIFF_OPT_CLR(diffopt, IGNORE_DIRTY_SUBMODULES);
249
250         if (!strcmp(arg, "all"))
251                 DIFF_OPT_SET(diffopt, IGNORE_SUBMODULES);
252         else if (!strcmp(arg, "untracked"))
253                 DIFF_OPT_SET(diffopt, IGNORE_UNTRACKED_IN_SUBMODULES);
254         else if (!strcmp(arg, "dirty"))
255                 DIFF_OPT_SET(diffopt, IGNORE_DIRTY_SUBMODULES);
256         else if (strcmp(arg, "none"))
257                 die("bad --ignore-submodules argument: %s", arg);
258 }
259
260 static int prepare_submodule_summary(struct rev_info *rev, const char *path,
261                 struct commit *left, struct commit *right,
262                 struct commit_list *merge_bases)
263 {
264         struct commit_list *list;
265
266         init_revisions(rev, NULL);
267         setup_revisions(0, NULL, rev, NULL);
268         rev->left_right = 1;
269         rev->first_parent_only = 1;
270         left->object.flags |= SYMMETRIC_LEFT;
271         add_pending_object(rev, &left->object, path);
272         add_pending_object(rev, &right->object, path);
273         for (list = merge_bases; list; list = list->next) {
274                 list->item->object.flags |= UNINTERESTING;
275                 add_pending_object(rev, &list->item->object,
276                         oid_to_hex(&list->item->object.oid));
277         }
278         return prepare_revision_walk(rev);
279 }
280
281 static void print_submodule_summary(struct rev_info *rev, FILE *f,
282                 const char *line_prefix,
283                 const char *del, const char *add, const char *reset)
284 {
285         static const char format[] = "  %m %s";
286         struct strbuf sb = STRBUF_INIT;
287         struct commit *commit;
288
289         while ((commit = get_revision(rev))) {
290                 struct pretty_print_context ctx = {0};
291                 ctx.date_mode = rev->date_mode;
292                 ctx.output_encoding = get_log_output_encoding();
293                 strbuf_setlen(&sb, 0);
294                 strbuf_addstr(&sb, line_prefix);
295                 if (commit->object.flags & SYMMETRIC_LEFT) {
296                         if (del)
297                                 strbuf_addstr(&sb, del);
298                 }
299                 else if (add)
300                         strbuf_addstr(&sb, add);
301                 format_commit_message(commit, format, &sb, &ctx);
302                 if (reset)
303                         strbuf_addstr(&sb, reset);
304                 strbuf_addch(&sb, '\n');
305                 fprintf(f, "%s", sb.buf);
306         }
307         strbuf_release(&sb);
308 }
309
310 /* Helper function to display the submodule header line prior to the full
311  * summary output. If it can locate the submodule objects directory it will
312  * attempt to lookup both the left and right commits and put them into the
313  * left and right pointers.
314  */
315 static void show_submodule_header(FILE *f, const char *path,
316                 const char *line_prefix,
317                 struct object_id *one, struct object_id *two,
318                 unsigned dirty_submodule, const char *meta,
319                 const char *reset,
320                 struct commit **left, struct commit **right,
321                 struct commit_list **merge_bases)
322 {
323         const char *message = NULL;
324         struct strbuf sb = STRBUF_INIT;
325         int fast_forward = 0, fast_backward = 0;
326
327         if (dirty_submodule & DIRTY_SUBMODULE_UNTRACKED)
328                 fprintf(f, "%sSubmodule %s contains untracked content\n",
329                         line_prefix, path);
330         if (dirty_submodule & DIRTY_SUBMODULE_MODIFIED)
331                 fprintf(f, "%sSubmodule %s contains modified content\n",
332                         line_prefix, path);
333
334         if (is_null_oid(one))
335                 message = "(new submodule)";
336         else if (is_null_oid(two))
337                 message = "(submodule deleted)";
338
339         if (add_submodule_odb(path)) {
340                 if (!message)
341                         message = "(not initialized)";
342                 goto output_header;
343         }
344
345         /*
346          * Attempt to lookup the commit references, and determine if this is
347          * a fast forward or fast backwards update.
348          */
349         *left = lookup_commit_reference(one->hash);
350         *right = lookup_commit_reference(two->hash);
351
352         /*
353          * Warn about missing commits in the submodule project, but only if
354          * they aren't null.
355          */
356         if ((!is_null_oid(one) && !*left) ||
357              (!is_null_oid(two) && !*right))
358                 message = "(commits not present)";
359
360         *merge_bases = get_merge_bases(*left, *right);
361         if (*merge_bases) {
362                 if ((*merge_bases)->item == *left)
363                         fast_forward = 1;
364                 else if ((*merge_bases)->item == *right)
365                         fast_backward = 1;
366         }
367
368         if (!oidcmp(one, two)) {
369                 strbuf_release(&sb);
370                 return;
371         }
372
373 output_header:
374         strbuf_addf(&sb, "%s%sSubmodule %s ", line_prefix, meta, path);
375         strbuf_add_unique_abbrev(&sb, one->hash, DEFAULT_ABBREV);
376         strbuf_addstr(&sb, (fast_backward || fast_forward) ? ".." : "...");
377         strbuf_add_unique_abbrev(&sb, two->hash, 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         strbuf_release(&sb);
385 }
386
387 void show_submodule_summary(FILE *f, const char *path,
388                 const char *line_prefix,
389                 struct object_id *one, struct object_id *two,
390                 unsigned dirty_submodule, const char *meta,
391                 const char *del, const char *add, const char *reset)
392 {
393         struct rev_info rev;
394         struct commit *left = NULL, *right = NULL;
395         struct commit_list *merge_bases = NULL;
396
397         show_submodule_header(f, path, line_prefix, one, two, dirty_submodule,
398                               meta, reset, &left, &right, &merge_bases);
399
400         /*
401          * If we don't have both a left and a right pointer, there is no
402          * reason to try and display a summary. The header line should contain
403          * all the information the user needs.
404          */
405         if (!left || !right)
406                 goto out;
407
408         /* Treat revision walker failure the same as missing commits */
409         if (prepare_submodule_summary(&rev, path, left, right, merge_bases)) {
410                 fprintf(f, "%s(revision walker failed)\n", line_prefix);
411                 goto out;
412         }
413
414         print_submodule_summary(&rev, f, line_prefix, del, add, reset);
415
416 out:
417         if (merge_bases)
418                 free_commit_list(merge_bases);
419         clear_commit_marks(left, ~0);
420         clear_commit_marks(right, ~0);
421 }
422
423 void show_submodule_inline_diff(FILE *f, const char *path,
424                 const char *line_prefix,
425                 struct object_id *one, struct object_id *two,
426                 unsigned dirty_submodule, const char *meta,
427                 const char *del, const char *add, const char *reset,
428                 const struct diff_options *o)
429 {
430         const struct object_id *old = &empty_tree_oid, *new = &empty_tree_oid;
431         struct commit *left = NULL, *right = NULL;
432         struct commit_list *merge_bases = NULL;
433         struct strbuf submodule_dir = STRBUF_INIT;
434         struct child_process cp = CHILD_PROCESS_INIT;
435
436         show_submodule_header(f, path, line_prefix, one, two, dirty_submodule,
437                               meta, reset, &left, &right, &merge_bases);
438
439         /* We need a valid left and right commit to display a difference */
440         if (!(left || is_null_oid(one)) ||
441             !(right || is_null_oid(two)))
442                 goto done;
443
444         if (left)
445                 old = one;
446         if (right)
447                 new = two;
448
449         fflush(f);
450         cp.git_cmd = 1;
451         cp.dir = path;
452         cp.out = dup(fileno(f));
453         cp.no_stdin = 1;
454
455         /* TODO: other options may need to be passed here. */
456         argv_array_push(&cp.args, "diff");
457         argv_array_pushf(&cp.args, "--line-prefix=%s", line_prefix);
458         if (DIFF_OPT_TST(o, REVERSE_DIFF)) {
459                 argv_array_pushf(&cp.args, "--src-prefix=%s%s/",
460                                  o->b_prefix, path);
461                 argv_array_pushf(&cp.args, "--dst-prefix=%s%s/",
462                                  o->a_prefix, path);
463         } else {
464                 argv_array_pushf(&cp.args, "--src-prefix=%s%s/",
465                                  o->a_prefix, path);
466                 argv_array_pushf(&cp.args, "--dst-prefix=%s%s/",
467                                  o->b_prefix, path);
468         }
469         argv_array_push(&cp.args, oid_to_hex(old));
470         /*
471          * If the submodule has modified content, we will diff against the
472          * work tree, under the assumption that the user has asked for the
473          * diff format and wishes to actually see all differences even if they
474          * haven't yet been committed to the submodule yet.
475          */
476         if (!(dirty_submodule & DIRTY_SUBMODULE_MODIFIED))
477                 argv_array_push(&cp.args, oid_to_hex(new));
478
479         if (run_command(&cp))
480                 fprintf(f, "(diff failed)\n");
481
482 done:
483         strbuf_release(&submodule_dir);
484         if (merge_bases)
485                 free_commit_list(merge_bases);
486         if (left)
487                 clear_commit_marks(left, ~0);
488         if (right)
489                 clear_commit_marks(right, ~0);
490 }
491
492 void set_config_fetch_recurse_submodules(int value)
493 {
494         config_fetch_recurse_submodules = value;
495 }
496
497 static int has_remote(const char *refname, const struct object_id *oid,
498                       int flags, void *cb_data)
499 {
500         return 1;
501 }
502
503 static int submodule_needs_pushing(const char *path, const unsigned char sha1[20])
504 {
505         if (add_submodule_odb(path) || !lookup_commit_reference(sha1))
506                 return 0;
507
508         if (for_each_remote_ref_submodule(path, has_remote, NULL) > 0) {
509                 struct child_process cp = CHILD_PROCESS_INIT;
510                 const char *argv[] = {"rev-list", NULL, "--not", "--remotes", "-n", "1" , NULL};
511                 struct strbuf buf = STRBUF_INIT;
512                 int needs_pushing = 0;
513
514                 argv[1] = sha1_to_hex(sha1);
515                 cp.argv = argv;
516                 prepare_submodule_repo_env(&cp.env_array);
517                 cp.git_cmd = 1;
518                 cp.no_stdin = 1;
519                 cp.out = -1;
520                 cp.dir = path;
521                 if (start_command(&cp))
522                         die("Could not run 'git rev-list %s --not --remotes -n 1' command in submodule %s",
523                                 sha1_to_hex(sha1), path);
524                 if (strbuf_read(&buf, cp.out, 41))
525                         needs_pushing = 1;
526                 finish_command(&cp);
527                 close(cp.out);
528                 strbuf_release(&buf);
529                 return needs_pushing;
530         }
531
532         return 0;
533 }
534
535 static void collect_submodules_from_diff(struct diff_queue_struct *q,
536                                          struct diff_options *options,
537                                          void *data)
538 {
539         int i;
540         struct string_list *needs_pushing = data;
541
542         for (i = 0; i < q->nr; i++) {
543                 struct diff_filepair *p = q->queue[i];
544                 if (!S_ISGITLINK(p->two->mode))
545                         continue;
546                 if (submodule_needs_pushing(p->two->path, p->two->oid.hash))
547                         string_list_insert(needs_pushing, p->two->path);
548         }
549 }
550
551 static void find_unpushed_submodule_commits(struct commit *commit,
552                 struct string_list *needs_pushing)
553 {
554         struct rev_info rev;
555
556         init_revisions(&rev, NULL);
557         rev.diffopt.output_format |= DIFF_FORMAT_CALLBACK;
558         rev.diffopt.format_callback = collect_submodules_from_diff;
559         rev.diffopt.format_callback_data = needs_pushing;
560         diff_tree_combined_merge(commit, 1, &rev);
561 }
562
563 int find_unpushed_submodules(unsigned char new_sha1[20],
564                 const char *remotes_name, struct string_list *needs_pushing)
565 {
566         struct rev_info rev;
567         struct commit *commit;
568         const char *argv[] = {NULL, NULL, "--not", "NULL", NULL};
569         int argc = ARRAY_SIZE(argv) - 1;
570         char *sha1_copy;
571
572         struct strbuf remotes_arg = STRBUF_INIT;
573
574         strbuf_addf(&remotes_arg, "--remotes=%s", remotes_name);
575         init_revisions(&rev, NULL);
576         sha1_copy = xstrdup(sha1_to_hex(new_sha1));
577         argv[1] = sha1_copy;
578         argv[3] = remotes_arg.buf;
579         setup_revisions(argc, argv, &rev, NULL);
580         if (prepare_revision_walk(&rev))
581                 die("revision walk setup failed");
582
583         while ((commit = get_revision(&rev)) != NULL)
584                 find_unpushed_submodule_commits(commit, needs_pushing);
585
586         reset_revision_walk();
587         free(sha1_copy);
588         strbuf_release(&remotes_arg);
589
590         return needs_pushing->nr;
591 }
592
593 static int push_submodule(const char *path)
594 {
595         if (add_submodule_odb(path))
596                 return 1;
597
598         if (for_each_remote_ref_submodule(path, has_remote, NULL) > 0) {
599                 struct child_process cp = CHILD_PROCESS_INIT;
600                 const char *argv[] = {"push", NULL};
601
602                 cp.argv = argv;
603                 prepare_submodule_repo_env(&cp.env_array);
604                 cp.git_cmd = 1;
605                 cp.no_stdin = 1;
606                 cp.dir = path;
607                 if (run_command(&cp))
608                         return 0;
609                 close(cp.out);
610         }
611
612         return 1;
613 }
614
615 int push_unpushed_submodules(unsigned char new_sha1[20], const char *remotes_name)
616 {
617         int i, ret = 1;
618         struct string_list needs_pushing = STRING_LIST_INIT_DUP;
619
620         if (!find_unpushed_submodules(new_sha1, remotes_name, &needs_pushing))
621                 return 1;
622
623         for (i = 0; i < needs_pushing.nr; i++) {
624                 const char *path = needs_pushing.items[i].string;
625                 fprintf(stderr, "Pushing submodule '%s'\n", path);
626                 if (!push_submodule(path)) {
627                         fprintf(stderr, "Unable to push submodule '%s'\n", path);
628                         ret = 0;
629                 }
630         }
631
632         string_list_clear(&needs_pushing, 0);
633
634         return ret;
635 }
636
637 static int is_submodule_commit_present(const char *path, unsigned char sha1[20])
638 {
639         int is_present = 0;
640         if (!add_submodule_odb(path) && lookup_commit_reference(sha1)) {
641                 /* Even if the submodule is checked out and the commit is
642                  * present, make sure it is reachable from a ref. */
643                 struct child_process cp = CHILD_PROCESS_INIT;
644                 const char *argv[] = {"rev-list", "-n", "1", NULL, "--not", "--all", NULL};
645                 struct strbuf buf = STRBUF_INIT;
646
647                 argv[3] = sha1_to_hex(sha1);
648                 cp.argv = argv;
649                 prepare_submodule_repo_env(&cp.env_array);
650                 cp.git_cmd = 1;
651                 cp.no_stdin = 1;
652                 cp.dir = path;
653                 if (!capture_command(&cp, &buf, 1024) && !buf.len)
654                         is_present = 1;
655
656                 strbuf_release(&buf);
657         }
658         return is_present;
659 }
660
661 static void submodule_collect_changed_cb(struct diff_queue_struct *q,
662                                          struct diff_options *options,
663                                          void *data)
664 {
665         int i;
666         for (i = 0; i < q->nr; i++) {
667                 struct diff_filepair *p = q->queue[i];
668                 if (!S_ISGITLINK(p->two->mode))
669                         continue;
670
671                 if (S_ISGITLINK(p->one->mode)) {
672                         /* NEEDSWORK: We should honor the name configured in
673                          * the .gitmodules file of the commit we are examining
674                          * here to be able to correctly follow submodules
675                          * being moved around. */
676                         struct string_list_item *path;
677                         path = unsorted_string_list_lookup(&changed_submodule_paths, p->two->path);
678                         if (!path && !is_submodule_commit_present(p->two->path, p->two->oid.hash))
679                                 string_list_append(&changed_submodule_paths, xstrdup(p->two->path));
680                 } else {
681                         /* Submodule is new or was moved here */
682                         /* NEEDSWORK: When the .git directories of submodules
683                          * live inside the superprojects .git directory some
684                          * day we should fetch new submodules directly into
685                          * that location too when config or options request
686                          * that so they can be checked out from there. */
687                         continue;
688                 }
689         }
690 }
691
692 static int add_sha1_to_array(const char *ref, const struct object_id *oid,
693                              int flags, void *data)
694 {
695         sha1_array_append(data, oid->hash);
696         return 0;
697 }
698
699 void check_for_new_submodule_commits(unsigned char new_sha1[20])
700 {
701         if (!initialized_fetch_ref_tips) {
702                 for_each_ref(add_sha1_to_array, &ref_tips_before_fetch);
703                 initialized_fetch_ref_tips = 1;
704         }
705
706         sha1_array_append(&ref_tips_after_fetch, new_sha1);
707 }
708
709 static int add_sha1_to_argv(const unsigned char sha1[20], void *data)
710 {
711         argv_array_push(data, sha1_to_hex(sha1));
712         return 0;
713 }
714
715 static void calculate_changed_submodule_paths(void)
716 {
717         struct rev_info rev;
718         struct commit *commit;
719         struct argv_array argv = ARGV_ARRAY_INIT;
720
721         /* No need to check if there are no submodules configured */
722         if (!submodule_from_path(NULL, NULL))
723                 return;
724
725         init_revisions(&rev, NULL);
726         argv_array_push(&argv, "--"); /* argv[0] program name */
727         sha1_array_for_each_unique(&ref_tips_after_fetch,
728                                    add_sha1_to_argv, &argv);
729         argv_array_push(&argv, "--not");
730         sha1_array_for_each_unique(&ref_tips_before_fetch,
731                                    add_sha1_to_argv, &argv);
732         setup_revisions(argv.argc, argv.argv, &rev, NULL);
733         if (prepare_revision_walk(&rev))
734                 die("revision walk setup failed");
735
736         /*
737          * Collect all submodules (whether checked out or not) for which new
738          * commits have been recorded upstream in "changed_submodule_paths".
739          */
740         while ((commit = get_revision(&rev))) {
741                 struct commit_list *parent = commit->parents;
742                 while (parent) {
743                         struct diff_options diff_opts;
744                         diff_setup(&diff_opts);
745                         DIFF_OPT_SET(&diff_opts, RECURSIVE);
746                         diff_opts.output_format |= DIFF_FORMAT_CALLBACK;
747                         diff_opts.format_callback = submodule_collect_changed_cb;
748                         diff_setup_done(&diff_opts);
749                         diff_tree_sha1(parent->item->object.oid.hash, commit->object.oid.hash, "", &diff_opts);
750                         diffcore_std(&diff_opts);
751                         diff_flush(&diff_opts);
752                         parent = parent->next;
753                 }
754         }
755
756         argv_array_clear(&argv);
757         sha1_array_clear(&ref_tips_before_fetch);
758         sha1_array_clear(&ref_tips_after_fetch);
759         initialized_fetch_ref_tips = 0;
760 }
761
762 struct submodule_parallel_fetch {
763         int count;
764         struct argv_array args;
765         const char *work_tree;
766         const char *prefix;
767         int command_line_option;
768         int quiet;
769         int result;
770 };
771 #define SPF_INIT {0, ARGV_ARRAY_INIT, NULL, NULL, 0, 0, 0}
772
773 static int get_next_submodule(struct child_process *cp,
774                               struct strbuf *err, void *data, void **task_cb)
775 {
776         int ret = 0;
777         struct submodule_parallel_fetch *spf = data;
778
779         for (; spf->count < active_nr; spf->count++) {
780                 struct strbuf submodule_path = STRBUF_INIT;
781                 struct strbuf submodule_git_dir = STRBUF_INIT;
782                 struct strbuf submodule_prefix = STRBUF_INIT;
783                 const struct cache_entry *ce = active_cache[spf->count];
784                 const char *git_dir, *default_argv;
785                 const struct submodule *submodule;
786
787                 if (!S_ISGITLINK(ce->ce_mode))
788                         continue;
789
790                 submodule = submodule_from_path(null_sha1, ce->name);
791                 if (!submodule)
792                         submodule = submodule_from_name(null_sha1, ce->name);
793
794                 default_argv = "yes";
795                 if (spf->command_line_option == RECURSE_SUBMODULES_DEFAULT) {
796                         if (submodule &&
797                             submodule->fetch_recurse !=
798                                                 RECURSE_SUBMODULES_NONE) {
799                                 if (submodule->fetch_recurse ==
800                                                 RECURSE_SUBMODULES_OFF)
801                                         continue;
802                                 if (submodule->fetch_recurse ==
803                                                 RECURSE_SUBMODULES_ON_DEMAND) {
804                                         if (!unsorted_string_list_lookup(&changed_submodule_paths, ce->name))
805                                                 continue;
806                                         default_argv = "on-demand";
807                                 }
808                         } else {
809                                 if ((config_fetch_recurse_submodules == RECURSE_SUBMODULES_OFF) ||
810                                     gitmodules_is_unmerged)
811                                         continue;
812                                 if (config_fetch_recurse_submodules == RECURSE_SUBMODULES_ON_DEMAND) {
813                                         if (!unsorted_string_list_lookup(&changed_submodule_paths, ce->name))
814                                                 continue;
815                                         default_argv = "on-demand";
816                                 }
817                         }
818                 } else if (spf->command_line_option == RECURSE_SUBMODULES_ON_DEMAND) {
819                         if (!unsorted_string_list_lookup(&changed_submodule_paths, ce->name))
820                                 continue;
821                         default_argv = "on-demand";
822                 }
823
824                 strbuf_addf(&submodule_path, "%s/%s", spf->work_tree, ce->name);
825                 strbuf_addf(&submodule_git_dir, "%s/.git", submodule_path.buf);
826                 strbuf_addf(&submodule_prefix, "%s%s/", spf->prefix, ce->name);
827                 git_dir = read_gitfile(submodule_git_dir.buf);
828                 if (!git_dir)
829                         git_dir = submodule_git_dir.buf;
830                 if (is_directory(git_dir)) {
831                         child_process_init(cp);
832                         cp->dir = strbuf_detach(&submodule_path, NULL);
833                         prepare_submodule_repo_env(&cp->env_array);
834                         cp->git_cmd = 1;
835                         if (!spf->quiet)
836                                 strbuf_addf(err, "Fetching submodule %s%s\n",
837                                             spf->prefix, ce->name);
838                         argv_array_init(&cp->args);
839                         argv_array_pushv(&cp->args, spf->args.argv);
840                         argv_array_push(&cp->args, default_argv);
841                         argv_array_push(&cp->args, "--submodule-prefix");
842                         argv_array_push(&cp->args, submodule_prefix.buf);
843                         ret = 1;
844                 }
845                 strbuf_release(&submodule_path);
846                 strbuf_release(&submodule_git_dir);
847                 strbuf_release(&submodule_prefix);
848                 if (ret) {
849                         spf->count++;
850                         return 1;
851                 }
852         }
853         return 0;
854 }
855
856 static int fetch_start_failure(struct strbuf *err,
857                                void *cb, void *task_cb)
858 {
859         struct submodule_parallel_fetch *spf = cb;
860
861         spf->result = 1;
862
863         return 0;
864 }
865
866 static int fetch_finish(int retvalue, struct strbuf *err,
867                         void *cb, void *task_cb)
868 {
869         struct submodule_parallel_fetch *spf = cb;
870
871         if (retvalue)
872                 spf->result = 1;
873
874         return 0;
875 }
876
877 int fetch_populated_submodules(const struct argv_array *options,
878                                const char *prefix, int command_line_option,
879                                int quiet, int max_parallel_jobs)
880 {
881         int i;
882         struct submodule_parallel_fetch spf = SPF_INIT;
883
884         spf.work_tree = get_git_work_tree();
885         spf.command_line_option = command_line_option;
886         spf.quiet = quiet;
887         spf.prefix = prefix;
888
889         if (!spf.work_tree)
890                 goto out;
891
892         if (read_cache() < 0)
893                 die("index file corrupt");
894
895         argv_array_push(&spf.args, "fetch");
896         for (i = 0; i < options->argc; i++)
897                 argv_array_push(&spf.args, options->argv[i]);
898         argv_array_push(&spf.args, "--recurse-submodules-default");
899         /* default value, "--submodule-prefix" and its value are added later */
900
901         if (max_parallel_jobs < 0)
902                 max_parallel_jobs = parallel_jobs;
903
904         calculate_changed_submodule_paths();
905         run_processes_parallel(max_parallel_jobs,
906                                get_next_submodule,
907                                fetch_start_failure,
908                                fetch_finish,
909                                &spf);
910
911         argv_array_clear(&spf.args);
912 out:
913         string_list_clear(&changed_submodule_paths, 1);
914         return spf.result;
915 }
916
917 unsigned is_submodule_modified(const char *path, int ignore_untracked)
918 {
919         ssize_t len;
920         struct child_process cp = CHILD_PROCESS_INIT;
921         const char *argv[] = {
922                 "status",
923                 "--porcelain",
924                 NULL,
925                 NULL,
926         };
927         struct strbuf buf = STRBUF_INIT;
928         unsigned dirty_submodule = 0;
929         const char *line, *next_line;
930         const char *git_dir;
931
932         strbuf_addf(&buf, "%s/.git", path);
933         git_dir = read_gitfile(buf.buf);
934         if (!git_dir)
935                 git_dir = buf.buf;
936         if (!is_directory(git_dir)) {
937                 strbuf_release(&buf);
938                 /* The submodule is not checked out, so it is not modified */
939                 return 0;
940
941         }
942         strbuf_reset(&buf);
943
944         if (ignore_untracked)
945                 argv[2] = "-uno";
946
947         cp.argv = argv;
948         prepare_submodule_repo_env(&cp.env_array);
949         cp.git_cmd = 1;
950         cp.no_stdin = 1;
951         cp.out = -1;
952         cp.dir = path;
953         if (start_command(&cp))
954                 die("Could not run 'git status --porcelain' in submodule %s", path);
955
956         len = strbuf_read(&buf, cp.out, 1024);
957         line = buf.buf;
958         while (len > 2) {
959                 if ((line[0] == '?') && (line[1] == '?')) {
960                         dirty_submodule |= DIRTY_SUBMODULE_UNTRACKED;
961                         if (dirty_submodule & DIRTY_SUBMODULE_MODIFIED)
962                                 break;
963                 } else {
964                         dirty_submodule |= DIRTY_SUBMODULE_MODIFIED;
965                         if (ignore_untracked ||
966                             (dirty_submodule & DIRTY_SUBMODULE_UNTRACKED))
967                                 break;
968                 }
969                 next_line = strchr(line, '\n');
970                 if (!next_line)
971                         break;
972                 next_line++;
973                 len -= (next_line - line);
974                 line = next_line;
975         }
976         close(cp.out);
977
978         if (finish_command(&cp))
979                 die("'git status --porcelain' failed in submodule %s", path);
980
981         strbuf_release(&buf);
982         return dirty_submodule;
983 }
984
985 int submodule_uses_gitfile(const char *path)
986 {
987         struct child_process cp = CHILD_PROCESS_INIT;
988         const char *argv[] = {
989                 "submodule",
990                 "foreach",
991                 "--quiet",
992                 "--recursive",
993                 "test -f .git",
994                 NULL,
995         };
996         struct strbuf buf = STRBUF_INIT;
997         const char *git_dir;
998
999         strbuf_addf(&buf, "%s/.git", path);
1000         git_dir = read_gitfile(buf.buf);
1001         if (!git_dir) {
1002                 strbuf_release(&buf);
1003                 return 0;
1004         }
1005         strbuf_release(&buf);
1006
1007         /* Now test that all nested submodules use a gitfile too */
1008         cp.argv = argv;
1009         prepare_submodule_repo_env(&cp.env_array);
1010         cp.git_cmd = 1;
1011         cp.no_stdin = 1;
1012         cp.no_stderr = 1;
1013         cp.no_stdout = 1;
1014         cp.dir = path;
1015         if (run_command(&cp))
1016                 return 0;
1017
1018         return 1;
1019 }
1020
1021 int ok_to_remove_submodule(const char *path)
1022 {
1023         ssize_t len;
1024         struct child_process cp = CHILD_PROCESS_INIT;
1025         const char *argv[] = {
1026                 "status",
1027                 "--porcelain",
1028                 "-u",
1029                 "--ignore-submodules=none",
1030                 NULL,
1031         };
1032         struct strbuf buf = STRBUF_INIT;
1033         int ok_to_remove = 1;
1034
1035         if (!file_exists(path) || is_empty_dir(path))
1036                 return 1;
1037
1038         if (!submodule_uses_gitfile(path))
1039                 return 0;
1040
1041         cp.argv = argv;
1042         prepare_submodule_repo_env(&cp.env_array);
1043         cp.git_cmd = 1;
1044         cp.no_stdin = 1;
1045         cp.out = -1;
1046         cp.dir = path;
1047         if (start_command(&cp))
1048                 die("Could not run 'git status --porcelain -uall --ignore-submodules=none' in submodule %s", path);
1049
1050         len = strbuf_read(&buf, cp.out, 1024);
1051         if (len > 2)
1052                 ok_to_remove = 0;
1053         close(cp.out);
1054
1055         if (finish_command(&cp))
1056                 die("'git status --porcelain -uall --ignore-submodules=none' failed in submodule %s", path);
1057
1058         strbuf_release(&buf);
1059         return ok_to_remove;
1060 }
1061
1062 static int find_first_merges(struct object_array *result, const char *path,
1063                 struct commit *a, struct commit *b)
1064 {
1065         int i, j;
1066         struct object_array merges = OBJECT_ARRAY_INIT;
1067         struct commit *commit;
1068         int contains_another;
1069
1070         char merged_revision[42];
1071         const char *rev_args[] = { "rev-list", "--merges", "--ancestry-path",
1072                                    "--all", merged_revision, NULL };
1073         struct rev_info revs;
1074         struct setup_revision_opt rev_opts;
1075
1076         memset(result, 0, sizeof(struct object_array));
1077         memset(&rev_opts, 0, sizeof(rev_opts));
1078
1079         /* get all revisions that merge commit a */
1080         snprintf(merged_revision, sizeof(merged_revision), "^%s",
1081                         oid_to_hex(&a->object.oid));
1082         init_revisions(&revs, NULL);
1083         rev_opts.submodule = path;
1084         setup_revisions(ARRAY_SIZE(rev_args)-1, rev_args, &revs, &rev_opts);
1085
1086         /* save all revisions from the above list that contain b */
1087         if (prepare_revision_walk(&revs))
1088                 die("revision walk setup failed");
1089         while ((commit = get_revision(&revs)) != NULL) {
1090                 struct object *o = &(commit->object);
1091                 if (in_merge_bases(b, commit))
1092                         add_object_array(o, NULL, &merges);
1093         }
1094         reset_revision_walk();
1095
1096         /* Now we've got all merges that contain a and b. Prune all
1097          * merges that contain another found merge and save them in
1098          * result.
1099          */
1100         for (i = 0; i < merges.nr; i++) {
1101                 struct commit *m1 = (struct commit *) merges.objects[i].item;
1102
1103                 contains_another = 0;
1104                 for (j = 0; j < merges.nr; j++) {
1105                         struct commit *m2 = (struct commit *) merges.objects[j].item;
1106                         if (i != j && in_merge_bases(m2, m1)) {
1107                                 contains_another = 1;
1108                                 break;
1109                         }
1110                 }
1111
1112                 if (!contains_another)
1113                         add_object_array(merges.objects[i].item, NULL, result);
1114         }
1115
1116         free(merges.objects);
1117         return result->nr;
1118 }
1119
1120 static void print_commit(struct commit *commit)
1121 {
1122         struct strbuf sb = STRBUF_INIT;
1123         struct pretty_print_context ctx = {0};
1124         ctx.date_mode.type = DATE_NORMAL;
1125         format_commit_message(commit, " %h: %m %s", &sb, &ctx);
1126         fprintf(stderr, "%s\n", sb.buf);
1127         strbuf_release(&sb);
1128 }
1129
1130 #define MERGE_WARNING(path, msg) \
1131         warning("Failed to merge submodule %s (%s)", path, msg);
1132
1133 int merge_submodule(unsigned char result[20], const char *path,
1134                     const unsigned char base[20], const unsigned char a[20],
1135                     const unsigned char b[20], int search)
1136 {
1137         struct commit *commit_base, *commit_a, *commit_b;
1138         int parent_count;
1139         struct object_array merges;
1140
1141         int i;
1142
1143         /* store a in result in case we fail */
1144         hashcpy(result, a);
1145
1146         /* we can not handle deletion conflicts */
1147         if (is_null_sha1(base))
1148                 return 0;
1149         if (is_null_sha1(a))
1150                 return 0;
1151         if (is_null_sha1(b))
1152                 return 0;
1153
1154         if (add_submodule_odb(path)) {
1155                 MERGE_WARNING(path, "not checked out");
1156                 return 0;
1157         }
1158
1159         if (!(commit_base = lookup_commit_reference(base)) ||
1160             !(commit_a = lookup_commit_reference(a)) ||
1161             !(commit_b = lookup_commit_reference(b))) {
1162                 MERGE_WARNING(path, "commits not present");
1163                 return 0;
1164         }
1165
1166         /* check whether both changes are forward */
1167         if (!in_merge_bases(commit_base, commit_a) ||
1168             !in_merge_bases(commit_base, commit_b)) {
1169                 MERGE_WARNING(path, "commits don't follow merge-base");
1170                 return 0;
1171         }
1172
1173         /* Case #1: a is contained in b or vice versa */
1174         if (in_merge_bases(commit_a, commit_b)) {
1175                 hashcpy(result, b);
1176                 return 1;
1177         }
1178         if (in_merge_bases(commit_b, commit_a)) {
1179                 hashcpy(result, a);
1180                 return 1;
1181         }
1182
1183         /*
1184          * Case #2: There are one or more merges that contain a and b in
1185          * the submodule. If there is only one, then present it as a
1186          * suggestion to the user, but leave it marked unmerged so the
1187          * user needs to confirm the resolution.
1188          */
1189
1190         /* Skip the search if makes no sense to the calling context.  */
1191         if (!search)
1192                 return 0;
1193
1194         /* find commit which merges them */
1195         parent_count = find_first_merges(&merges, path, commit_a, commit_b);
1196         switch (parent_count) {
1197         case 0:
1198                 MERGE_WARNING(path, "merge following commits not found");
1199                 break;
1200
1201         case 1:
1202                 MERGE_WARNING(path, "not fast-forward");
1203                 fprintf(stderr, "Found a possible merge resolution "
1204                                 "for the submodule:\n");
1205                 print_commit((struct commit *) merges.objects[0].item);
1206                 fprintf(stderr,
1207                         "If this is correct simply add it to the index "
1208                         "for example\n"
1209                         "by using:\n\n"
1210                         "  git update-index --cacheinfo 160000 %s \"%s\"\n\n"
1211                         "which will accept this suggestion.\n",
1212                         oid_to_hex(&merges.objects[0].item->oid), path);
1213                 break;
1214
1215         default:
1216                 MERGE_WARNING(path, "multiple merges found");
1217                 for (i = 0; i < merges.nr; i++)
1218                         print_commit((struct commit *) merges.objects[i].item);
1219         }
1220
1221         free(merges.objects);
1222         return 0;
1223 }
1224
1225 /* Update gitfile and core.worktree setting to connect work tree and git dir */
1226 void connect_work_tree_and_git_dir(const char *work_tree, const char *git_dir)
1227 {
1228         struct strbuf file_name = STRBUF_INIT;
1229         struct strbuf rel_path = STRBUF_INIT;
1230         const char *real_work_tree = xstrdup(real_path(work_tree));
1231
1232         /* Update gitfile */
1233         strbuf_addf(&file_name, "%s/.git", work_tree);
1234         write_file(file_name.buf, "gitdir: %s",
1235                    relative_path(git_dir, real_work_tree, &rel_path));
1236
1237         /* Update core.worktree setting */
1238         strbuf_reset(&file_name);
1239         strbuf_addf(&file_name, "%s/config", git_dir);
1240         git_config_set_in_file(file_name.buf, "core.worktree",
1241                                relative_path(real_work_tree, git_dir,
1242                                              &rel_path));
1243
1244         strbuf_release(&file_name);
1245         strbuf_release(&rel_path);
1246         free((void *)real_work_tree);
1247 }
1248
1249 int parallel_submodules(void)
1250 {
1251         return parallel_jobs;
1252 }
1253
1254 void prepare_submodule_repo_env(struct argv_array *out)
1255 {
1256         const char * const *var;
1257
1258         for (var = local_repo_env; *var; var++) {
1259                 if (strcmp(*var, CONFIG_DATA_ENVIRONMENT))
1260                         argv_array_push(out, *var);
1261         }
1262         argv_array_push(out, "GIT_DIR=.git");
1263 }