http-walker: simplify process_alternates_response() using strbuf
[git] / submodule.c
1 #include "cache.h"
2 #include "submodule.h"
3 #include "dir.h"
4 #include "diff.h"
5 #include "commit.h"
6 #include "revision.h"
7 #include "run-command.h"
8 #include "diffcore.h"
9 #include "refs.h"
10 #include "string-list.h"
11 #include "sha1-array.h"
12 #include "argv-array.h"
13 #include "blob.h"
14
15 static struct string_list config_name_for_path;
16 static struct string_list config_fetch_recurse_submodules_for_name;
17 static struct string_list config_ignore_for_name;
18 static int config_fetch_recurse_submodules = RECURSE_SUBMODULES_ON_DEMAND;
19 static struct string_list changed_submodule_paths;
20 static int initialized_fetch_ref_tips;
21 static struct sha1_array ref_tips_before_fetch;
22 static struct sha1_array ref_tips_after_fetch;
23
24 /*
25  * The following flag is set if the .gitmodules file is unmerged. We then
26  * disable recursion for all submodules where .git/config doesn't have a
27  * matching config entry because we can't guess what might be configured in
28  * .gitmodules unless the user resolves the conflict. When a command line
29  * option is given (which always overrides configuration) this flag will be
30  * ignored.
31  */
32 static int gitmodules_is_unmerged;
33
34 /*
35  * This flag is set if the .gitmodules file had unstaged modifications on
36  * startup. This must be checked before allowing modifications to the
37  * .gitmodules file with the intention to stage them later, because when
38  * continuing we would stage the modifications the user didn't stage herself
39  * too. That might change in a future version when we learn to stage the
40  * changes we do ourselves without staging any previous modifications.
41  */
42 static int gitmodules_is_modified;
43
44
45 int is_staging_gitmodules_ok(void)
46 {
47         return !gitmodules_is_modified;
48 }
49
50 /*
51  * Try to update the "path" entry in the "submodule.<name>" section of the
52  * .gitmodules file. Return 0 only if a .gitmodules file was found, a section
53  * with the correct path=<oldpath> setting was found and we could update it.
54  */
55 int update_path_in_gitmodules(const char *oldpath, const char *newpath)
56 {
57         struct strbuf entry = STRBUF_INIT;
58         struct string_list_item *path_option;
59
60         if (!file_exists(".gitmodules")) /* Do nothing without .gitmodules */
61                 return -1;
62
63         if (gitmodules_is_unmerged)
64                 die(_("Cannot change unmerged .gitmodules, resolve merge conflicts first"));
65
66         path_option = unsorted_string_list_lookup(&config_name_for_path, oldpath);
67         if (!path_option) {
68                 warning(_("Could not find section in .gitmodules where path=%s"), oldpath);
69                 return -1;
70         }
71         strbuf_addstr(&entry, "submodule.");
72         strbuf_addstr(&entry, path_option->util);
73         strbuf_addstr(&entry, ".path");
74         if (git_config_set_in_file(".gitmodules", entry.buf, newpath) < 0) {
75                 /* Maybe the user already did that, don't error out here */
76                 warning(_("Could not update .gitmodules entry %s"), entry.buf);
77                 strbuf_release(&entry);
78                 return -1;
79         }
80         strbuf_release(&entry);
81         return 0;
82 }
83
84 /*
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         struct string_list_item *path_option;
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         path_option = unsorted_string_list_lookup(&config_name_for_path, path);
101         if (!path_option) {
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, path_option->util);
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         const char *git_dir;
129
130         strbuf_addf(&objects_directory, "%s/.git", path);
131         git_dir = read_gitfile(objects_directory.buf);
132         if (git_dir) {
133                 strbuf_reset(&objects_directory);
134                 strbuf_addstr(&objects_directory, git_dir);
135         }
136         strbuf_addstr(&objects_directory, "/objects/");
137         if (!is_directory(objects_directory.buf)) {
138                 ret = -1;
139                 goto done;
140         }
141         /* avoid adding it twice */
142         for (alt_odb = alt_odb_list; alt_odb; alt_odb = alt_odb->next)
143                 if (alt_odb->name - alt_odb->base == objects_directory.len &&
144                                 !strncmp(alt_odb->base, objects_directory.buf,
145                                         objects_directory.len))
146                         goto done;
147
148         alt_odb = xmalloc(objects_directory.len + 42 + sizeof(*alt_odb));
149         alt_odb->next = alt_odb_list;
150         strcpy(alt_odb->base, objects_directory.buf);
151         alt_odb->name = alt_odb->base + objects_directory.len;
152         alt_odb->name[2] = '/';
153         alt_odb->name[40] = '\0';
154         alt_odb->name[41] = '\0';
155         alt_odb_list = alt_odb;
156
157         /* add possible alternates from the submodule */
158         read_info_alternates(objects_directory.buf, 0);
159         prepare_alt_odb();
160 done:
161         strbuf_release(&objects_directory);
162         return ret;
163 }
164
165 void set_diffopt_flags_from_submodule_config(struct diff_options *diffopt,
166                                              const char *path)
167 {
168         struct string_list_item *path_option, *ignore_option;
169         path_option = unsorted_string_list_lookup(&config_name_for_path, path);
170         if (path_option) {
171                 ignore_option = unsorted_string_list_lookup(&config_ignore_for_name, path_option->util);
172                 if (ignore_option)
173                         handle_ignore_submodules_arg(diffopt, ignore_option->util);
174                 else if (gitmodules_is_unmerged)
175                         DIFF_OPT_SET(diffopt, IGNORE_SUBMODULES);
176         }
177 }
178
179 int submodule_config(const char *var, const char *value, void *cb)
180 {
181         if (starts_with(var, "submodule."))
182                 return parse_submodule_config_option(var, value);
183         else if (!strcmp(var, "fetch.recursesubmodules")) {
184                 config_fetch_recurse_submodules = parse_fetch_recurse_submodules_arg(var, value);
185                 return 0;
186         }
187         return 0;
188 }
189
190 void gitmodules_config(void)
191 {
192         const char *work_tree = get_git_work_tree();
193         if (work_tree) {
194                 struct strbuf gitmodules_path = STRBUF_INIT;
195                 int pos;
196                 strbuf_addstr(&gitmodules_path, work_tree);
197                 strbuf_addstr(&gitmodules_path, "/.gitmodules");
198                 if (read_cache() < 0)
199                         die("index file corrupt");
200                 pos = cache_name_pos(".gitmodules", 11);
201                 if (pos < 0) { /* .gitmodules not found or isn't merged */
202                         pos = -1 - pos;
203                         if (active_nr > pos) {  /* there is a .gitmodules */
204                                 const struct cache_entry *ce = active_cache[pos];
205                                 if (ce_namelen(ce) == 11 &&
206                                     !memcmp(ce->name, ".gitmodules", 11))
207                                         gitmodules_is_unmerged = 1;
208                         }
209                 } else if (pos < active_nr) {
210                         struct stat st;
211                         if (lstat(".gitmodules", &st) == 0 &&
212                             ce_match_stat(active_cache[pos], &st, 0) & DATA_CHANGED)
213                                 gitmodules_is_modified = 1;
214                 }
215
216                 if (!gitmodules_is_unmerged)
217                         git_config_from_file(submodule_config, gitmodules_path.buf, NULL);
218                 strbuf_release(&gitmodules_path);
219         }
220 }
221
222 int parse_submodule_config_option(const char *var, const char *value)
223 {
224         struct string_list_item *config;
225         const char *name, *key;
226         int namelen;
227
228         if (parse_config_key(var, "submodule", &name, &namelen, &key) < 0 || !name)
229                 return 0;
230
231         if (!strcmp(key, "path")) {
232                 if (!value)
233                         return config_error_nonbool(var);
234
235                 config = unsorted_string_list_lookup(&config_name_for_path, value);
236                 if (config)
237                         free(config->util);
238                 else
239                         config = string_list_append(&config_name_for_path, xstrdup(value));
240                 config->util = xmemdupz(name, namelen);
241         } else if (!strcmp(key, "fetchrecursesubmodules")) {
242                 char *name_cstr = xmemdupz(name, namelen);
243                 config = unsorted_string_list_lookup(&config_fetch_recurse_submodules_for_name, name_cstr);
244                 if (!config)
245                         config = string_list_append(&config_fetch_recurse_submodules_for_name, name_cstr);
246                 else
247                         free(name_cstr);
248                 config->util = (void *)(intptr_t)parse_fetch_recurse_submodules_arg(var, value);
249         } else if (!strcmp(key, "ignore")) {
250                 char *name_cstr;
251
252                 if (!value)
253                         return config_error_nonbool(var);
254
255                 if (strcmp(value, "untracked") && strcmp(value, "dirty") &&
256                     strcmp(value, "all") && strcmp(value, "none")) {
257                         warning("Invalid parameter \"%s\" for config option \"submodule.%s.ignore\"", value, var);
258                         return 0;
259                 }
260
261                 name_cstr = xmemdupz(name, namelen);
262                 config = unsorted_string_list_lookup(&config_ignore_for_name, name_cstr);
263                 if (config) {
264                         free(config->util);
265                         free(name_cstr);
266                 } else
267                         config = string_list_append(&config_ignore_for_name, name_cstr);
268                 config->util = xstrdup(value);
269                 return 0;
270         }
271         return 0;
272 }
273
274 void handle_ignore_submodules_arg(struct diff_options *diffopt,
275                                   const char *arg)
276 {
277         DIFF_OPT_CLR(diffopt, IGNORE_SUBMODULES);
278         DIFF_OPT_CLR(diffopt, IGNORE_UNTRACKED_IN_SUBMODULES);
279         DIFF_OPT_CLR(diffopt, IGNORE_DIRTY_SUBMODULES);
280
281         if (!strcmp(arg, "all"))
282                 DIFF_OPT_SET(diffopt, IGNORE_SUBMODULES);
283         else if (!strcmp(arg, "untracked"))
284                 DIFF_OPT_SET(diffopt, IGNORE_UNTRACKED_IN_SUBMODULES);
285         else if (!strcmp(arg, "dirty"))
286                 DIFF_OPT_SET(diffopt, IGNORE_DIRTY_SUBMODULES);
287         else if (strcmp(arg, "none"))
288                 die("bad --ignore-submodules argument: %s", arg);
289 }
290
291 static int prepare_submodule_summary(struct rev_info *rev, const char *path,
292                 struct commit *left, struct commit *right,
293                 int *fast_forward, int *fast_backward)
294 {
295         struct commit_list *merge_bases, *list;
296
297         init_revisions(rev, NULL);
298         setup_revisions(0, NULL, rev, NULL);
299         rev->left_right = 1;
300         rev->first_parent_only = 1;
301         left->object.flags |= SYMMETRIC_LEFT;
302         add_pending_object(rev, &left->object, path);
303         add_pending_object(rev, &right->object, path);
304         merge_bases = get_merge_bases(left, right, 1);
305         if (merge_bases) {
306                 if (merge_bases->item == left)
307                         *fast_forward = 1;
308                 else if (merge_bases->item == right)
309                         *fast_backward = 1;
310         }
311         for (list = merge_bases; list; list = list->next) {
312                 list->item->object.flags |= UNINTERESTING;
313                 add_pending_object(rev, &list->item->object,
314                         sha1_to_hex(list->item->object.sha1));
315         }
316         return prepare_revision_walk(rev);
317 }
318
319 static void print_submodule_summary(struct rev_info *rev, FILE *f,
320                 const char *line_prefix,
321                 const char *del, const char *add, const char *reset)
322 {
323         static const char format[] = "  %m %s";
324         struct strbuf sb = STRBUF_INIT;
325         struct commit *commit;
326
327         while ((commit = get_revision(rev))) {
328                 struct pretty_print_context ctx = {0};
329                 ctx.date_mode = rev->date_mode;
330                 ctx.output_encoding = get_log_output_encoding();
331                 strbuf_setlen(&sb, 0);
332                 strbuf_addstr(&sb, line_prefix);
333                 if (commit->object.flags & SYMMETRIC_LEFT) {
334                         if (del)
335                                 strbuf_addstr(&sb, del);
336                 }
337                 else if (add)
338                         strbuf_addstr(&sb, add);
339                 format_commit_message(commit, format, &sb, &ctx);
340                 if (reset)
341                         strbuf_addstr(&sb, reset);
342                 strbuf_addch(&sb, '\n');
343                 fprintf(f, "%s", sb.buf);
344         }
345         strbuf_release(&sb);
346 }
347
348 int parse_fetch_recurse_submodules_arg(const char *opt, const char *arg)
349 {
350         switch (git_config_maybe_bool(opt, arg)) {
351         case 1:
352                 return RECURSE_SUBMODULES_ON;
353         case 0:
354                 return RECURSE_SUBMODULES_OFF;
355         default:
356                 if (!strcmp(arg, "on-demand"))
357                         return RECURSE_SUBMODULES_ON_DEMAND;
358                 die("bad %s argument: %s", opt, arg);
359         }
360 }
361
362 void show_submodule_summary(FILE *f, const char *path,
363                 const char *line_prefix,
364                 unsigned char one[20], unsigned char two[20],
365                 unsigned dirty_submodule, const char *meta,
366                 const char *del, const char *add, const char *reset)
367 {
368         struct rev_info rev;
369         struct commit *left = NULL, *right = NULL;
370         const char *message = NULL;
371         struct strbuf sb = STRBUF_INIT;
372         int fast_forward = 0, fast_backward = 0;
373
374         if (is_null_sha1(two))
375                 message = "(submodule deleted)";
376         else if (add_submodule_odb(path))
377                 message = "(not checked out)";
378         else if (is_null_sha1(one))
379                 message = "(new submodule)";
380         else if (!(left = lookup_commit_reference(one)) ||
381                  !(right = lookup_commit_reference(two)))
382                 message = "(commits not present)";
383         else if (prepare_submodule_summary(&rev, path, left, right,
384                                            &fast_forward, &fast_backward))
385                 message = "(revision walker failed)";
386
387         if (dirty_submodule & DIRTY_SUBMODULE_UNTRACKED)
388                 fprintf(f, "%sSubmodule %s contains untracked content\n",
389                         line_prefix, path);
390         if (dirty_submodule & DIRTY_SUBMODULE_MODIFIED)
391                 fprintf(f, "%sSubmodule %s contains modified content\n",
392                         line_prefix, path);
393
394         if (!hashcmp(one, two)) {
395                 strbuf_release(&sb);
396                 return;
397         }
398
399         strbuf_addf(&sb, "%s%sSubmodule %s %s..", line_prefix, meta, path,
400                         find_unique_abbrev(one, DEFAULT_ABBREV));
401         if (!fast_backward && !fast_forward)
402                 strbuf_addch(&sb, '.');
403         strbuf_addf(&sb, "%s", find_unique_abbrev(two, DEFAULT_ABBREV));
404         if (message)
405                 strbuf_addf(&sb, " %s%s\n", message, reset);
406         else
407                 strbuf_addf(&sb, "%s:%s\n", fast_backward ? " (rewind)" : "", reset);
408         fwrite(sb.buf, sb.len, 1, f);
409
410         if (!message) /* only NULL if we succeeded in setting up the walk */
411                 print_submodule_summary(&rev, f, line_prefix, del, add, reset);
412         if (left)
413                 clear_commit_marks(left, ~0);
414         if (right)
415                 clear_commit_marks(right, ~0);
416
417         strbuf_release(&sb);
418 }
419
420 void set_config_fetch_recurse_submodules(int value)
421 {
422         config_fetch_recurse_submodules = value;
423 }
424
425 static int has_remote(const char *refname, const unsigned char *sha1, int flags, void *cb_data)
426 {
427         return 1;
428 }
429
430 static int submodule_needs_pushing(const char *path, const unsigned char sha1[20])
431 {
432         if (add_submodule_odb(path) || !lookup_commit_reference(sha1))
433                 return 0;
434
435         if (for_each_remote_ref_submodule(path, has_remote, NULL) > 0) {
436                 struct child_process cp;
437                 const char *argv[] = {"rev-list", NULL, "--not", "--remotes", "-n", "1" , NULL};
438                 struct strbuf buf = STRBUF_INIT;
439                 int needs_pushing = 0;
440
441                 argv[1] = sha1_to_hex(sha1);
442                 memset(&cp, 0, sizeof(cp));
443                 cp.argv = argv;
444                 cp.env = local_repo_env;
445                 cp.git_cmd = 1;
446                 cp.no_stdin = 1;
447                 cp.out = -1;
448                 cp.dir = path;
449                 if (start_command(&cp))
450                         die("Could not run 'git rev-list %s --not --remotes -n 1' command in submodule %s",
451                                 sha1_to_hex(sha1), path);
452                 if (strbuf_read(&buf, cp.out, 41))
453                         needs_pushing = 1;
454                 finish_command(&cp);
455                 close(cp.out);
456                 strbuf_release(&buf);
457                 return needs_pushing;
458         }
459
460         return 0;
461 }
462
463 static void collect_submodules_from_diff(struct diff_queue_struct *q,
464                                          struct diff_options *options,
465                                          void *data)
466 {
467         int i;
468         struct string_list *needs_pushing = data;
469
470         for (i = 0; i < q->nr; i++) {
471                 struct diff_filepair *p = q->queue[i];
472                 if (!S_ISGITLINK(p->two->mode))
473                         continue;
474                 if (submodule_needs_pushing(p->two->path, p->two->sha1))
475                         string_list_insert(needs_pushing, p->two->path);
476         }
477 }
478
479 static void find_unpushed_submodule_commits(struct commit *commit,
480                 struct string_list *needs_pushing)
481 {
482         struct rev_info rev;
483
484         init_revisions(&rev, NULL);
485         rev.diffopt.output_format |= DIFF_FORMAT_CALLBACK;
486         rev.diffopt.format_callback = collect_submodules_from_diff;
487         rev.diffopt.format_callback_data = needs_pushing;
488         diff_tree_combined_merge(commit, 1, &rev);
489 }
490
491 int find_unpushed_submodules(unsigned char new_sha1[20],
492                 const char *remotes_name, struct string_list *needs_pushing)
493 {
494         struct rev_info rev;
495         struct commit *commit;
496         const char *argv[] = {NULL, NULL, "--not", "NULL", NULL};
497         int argc = ARRAY_SIZE(argv) - 1;
498         char *sha1_copy;
499
500         struct strbuf remotes_arg = STRBUF_INIT;
501
502         strbuf_addf(&remotes_arg, "--remotes=%s", remotes_name);
503         init_revisions(&rev, NULL);
504         sha1_copy = xstrdup(sha1_to_hex(new_sha1));
505         argv[1] = sha1_copy;
506         argv[3] = remotes_arg.buf;
507         setup_revisions(argc, argv, &rev, NULL);
508         if (prepare_revision_walk(&rev))
509                 die("revision walk setup failed");
510
511         while ((commit = get_revision(&rev)) != NULL)
512                 find_unpushed_submodule_commits(commit, needs_pushing);
513
514         reset_revision_walk();
515         free(sha1_copy);
516         strbuf_release(&remotes_arg);
517
518         return needs_pushing->nr;
519 }
520
521 static int push_submodule(const char *path)
522 {
523         if (add_submodule_odb(path))
524                 return 1;
525
526         if (for_each_remote_ref_submodule(path, has_remote, NULL) > 0) {
527                 struct child_process cp;
528                 const char *argv[] = {"push", NULL};
529
530                 memset(&cp, 0, sizeof(cp));
531                 cp.argv = argv;
532                 cp.env = local_repo_env;
533                 cp.git_cmd = 1;
534                 cp.no_stdin = 1;
535                 cp.dir = path;
536                 if (run_command(&cp))
537                         return 0;
538                 close(cp.out);
539         }
540
541         return 1;
542 }
543
544 int push_unpushed_submodules(unsigned char new_sha1[20], const char *remotes_name)
545 {
546         int i, ret = 1;
547         struct string_list needs_pushing = STRING_LIST_INIT_DUP;
548
549         if (!find_unpushed_submodules(new_sha1, remotes_name, &needs_pushing))
550                 return 1;
551
552         for (i = 0; i < needs_pushing.nr; i++) {
553                 const char *path = needs_pushing.items[i].string;
554                 fprintf(stderr, "Pushing submodule '%s'\n", path);
555                 if (!push_submodule(path)) {
556                         fprintf(stderr, "Unable to push submodule '%s'\n", path);
557                         ret = 0;
558                 }
559         }
560
561         string_list_clear(&needs_pushing, 0);
562
563         return ret;
564 }
565
566 static int is_submodule_commit_present(const char *path, unsigned char sha1[20])
567 {
568         int is_present = 0;
569         if (!add_submodule_odb(path) && lookup_commit_reference(sha1)) {
570                 /* Even if the submodule is checked out and the commit is
571                  * present, make sure it is reachable from a ref. */
572                 struct child_process cp;
573                 const char *argv[] = {"rev-list", "-n", "1", NULL, "--not", "--all", NULL};
574                 struct strbuf buf = STRBUF_INIT;
575
576                 argv[3] = sha1_to_hex(sha1);
577                 memset(&cp, 0, sizeof(cp));
578                 cp.argv = argv;
579                 cp.env = local_repo_env;
580                 cp.git_cmd = 1;
581                 cp.no_stdin = 1;
582                 cp.out = -1;
583                 cp.dir = path;
584                 if (!run_command(&cp) && !strbuf_read(&buf, cp.out, 1024))
585                         is_present = 1;
586
587                 close(cp.out);
588                 strbuf_release(&buf);
589         }
590         return is_present;
591 }
592
593 static void submodule_collect_changed_cb(struct diff_queue_struct *q,
594                                          struct diff_options *options,
595                                          void *data)
596 {
597         int i;
598         for (i = 0; i < q->nr; i++) {
599                 struct diff_filepair *p = q->queue[i];
600                 if (!S_ISGITLINK(p->two->mode))
601                         continue;
602
603                 if (S_ISGITLINK(p->one->mode)) {
604                         /* NEEDSWORK: We should honor the name configured in
605                          * the .gitmodules file of the commit we are examining
606                          * here to be able to correctly follow submodules
607                          * being moved around. */
608                         struct string_list_item *path;
609                         path = unsorted_string_list_lookup(&changed_submodule_paths, p->two->path);
610                         if (!path && !is_submodule_commit_present(p->two->path, p->two->sha1))
611                                 string_list_append(&changed_submodule_paths, xstrdup(p->two->path));
612                 } else {
613                         /* Submodule is new or was moved here */
614                         /* NEEDSWORK: When the .git directories of submodules
615                          * live inside the superprojects .git directory some
616                          * day we should fetch new submodules directly into
617                          * that location too when config or options request
618                          * that so they can be checked out from there. */
619                         continue;
620                 }
621         }
622 }
623
624 static int add_sha1_to_array(const char *ref, const unsigned char *sha1,
625                              int flags, void *data)
626 {
627         sha1_array_append(data, sha1);
628         return 0;
629 }
630
631 void check_for_new_submodule_commits(unsigned char new_sha1[20])
632 {
633         if (!initialized_fetch_ref_tips) {
634                 for_each_ref(add_sha1_to_array, &ref_tips_before_fetch);
635                 initialized_fetch_ref_tips = 1;
636         }
637
638         sha1_array_append(&ref_tips_after_fetch, new_sha1);
639 }
640
641 static void add_sha1_to_argv(const unsigned char sha1[20], void *data)
642 {
643         argv_array_push(data, sha1_to_hex(sha1));
644 }
645
646 static void calculate_changed_submodule_paths(void)
647 {
648         struct rev_info rev;
649         struct commit *commit;
650         struct argv_array argv = ARGV_ARRAY_INIT;
651
652         /* No need to check if there are no submodules configured */
653         if (!config_name_for_path.nr)
654                 return;
655
656         init_revisions(&rev, NULL);
657         argv_array_push(&argv, "--"); /* argv[0] program name */
658         sha1_array_for_each_unique(&ref_tips_after_fetch,
659                                    add_sha1_to_argv, &argv);
660         argv_array_push(&argv, "--not");
661         sha1_array_for_each_unique(&ref_tips_before_fetch,
662                                    add_sha1_to_argv, &argv);
663         setup_revisions(argv.argc, argv.argv, &rev, NULL);
664         if (prepare_revision_walk(&rev))
665                 die("revision walk setup failed");
666
667         /*
668          * Collect all submodules (whether checked out or not) for which new
669          * commits have been recorded upstream in "changed_submodule_paths".
670          */
671         while ((commit = get_revision(&rev))) {
672                 struct commit_list *parent = commit->parents;
673                 while (parent) {
674                         struct diff_options diff_opts;
675                         diff_setup(&diff_opts);
676                         DIFF_OPT_SET(&diff_opts, RECURSIVE);
677                         diff_opts.output_format |= DIFF_FORMAT_CALLBACK;
678                         diff_opts.format_callback = submodule_collect_changed_cb;
679                         diff_setup_done(&diff_opts);
680                         diff_tree_sha1(parent->item->object.sha1, commit->object.sha1, "", &diff_opts);
681                         diffcore_std(&diff_opts);
682                         diff_flush(&diff_opts);
683                         parent = parent->next;
684                 }
685         }
686
687         argv_array_clear(&argv);
688         sha1_array_clear(&ref_tips_before_fetch);
689         sha1_array_clear(&ref_tips_after_fetch);
690         initialized_fetch_ref_tips = 0;
691 }
692
693 int fetch_populated_submodules(const struct argv_array *options,
694                                const char *prefix, int command_line_option,
695                                int quiet)
696 {
697         int i, result = 0;
698         struct child_process cp;
699         struct argv_array argv = ARGV_ARRAY_INIT;
700         struct string_list_item *name_for_path;
701         const char *work_tree = get_git_work_tree();
702         if (!work_tree)
703                 goto out;
704
705         if (read_cache() < 0)
706                 die("index file corrupt");
707
708         argv_array_push(&argv, "fetch");
709         for (i = 0; i < options->argc; i++)
710                 argv_array_push(&argv, options->argv[i]);
711         argv_array_push(&argv, "--recurse-submodules-default");
712         /* default value, "--submodule-prefix" and its value are added later */
713
714         memset(&cp, 0, sizeof(cp));
715         cp.env = local_repo_env;
716         cp.git_cmd = 1;
717         cp.no_stdin = 1;
718
719         calculate_changed_submodule_paths();
720
721         for (i = 0; i < active_nr; i++) {
722                 struct strbuf submodule_path = STRBUF_INIT;
723                 struct strbuf submodule_git_dir = STRBUF_INIT;
724                 struct strbuf submodule_prefix = STRBUF_INIT;
725                 const struct cache_entry *ce = active_cache[i];
726                 const char *git_dir, *name, *default_argv;
727
728                 if (!S_ISGITLINK(ce->ce_mode))
729                         continue;
730
731                 name = ce->name;
732                 name_for_path = unsorted_string_list_lookup(&config_name_for_path, ce->name);
733                 if (name_for_path)
734                         name = name_for_path->util;
735
736                 default_argv = "yes";
737                 if (command_line_option == RECURSE_SUBMODULES_DEFAULT) {
738                         struct string_list_item *fetch_recurse_submodules_option;
739                         fetch_recurse_submodules_option = unsorted_string_list_lookup(&config_fetch_recurse_submodules_for_name, name);
740                         if (fetch_recurse_submodules_option) {
741                                 if ((intptr_t)fetch_recurse_submodules_option->util == RECURSE_SUBMODULES_OFF)
742                                         continue;
743                                 if ((intptr_t)fetch_recurse_submodules_option->util == RECURSE_SUBMODULES_ON_DEMAND) {
744                                         if (!unsorted_string_list_lookup(&changed_submodule_paths, ce->name))
745                                                 continue;
746                                         default_argv = "on-demand";
747                                 }
748                         } else {
749                                 if ((config_fetch_recurse_submodules == RECURSE_SUBMODULES_OFF) ||
750                                     gitmodules_is_unmerged)
751                                         continue;
752                                 if (config_fetch_recurse_submodules == RECURSE_SUBMODULES_ON_DEMAND) {
753                                         if (!unsorted_string_list_lookup(&changed_submodule_paths, ce->name))
754                                                 continue;
755                                         default_argv = "on-demand";
756                                 }
757                         }
758                 } else if (command_line_option == RECURSE_SUBMODULES_ON_DEMAND) {
759                         if (!unsorted_string_list_lookup(&changed_submodule_paths, ce->name))
760                                 continue;
761                         default_argv = "on-demand";
762                 }
763
764                 strbuf_addf(&submodule_path, "%s/%s", work_tree, ce->name);
765                 strbuf_addf(&submodule_git_dir, "%s/.git", submodule_path.buf);
766                 strbuf_addf(&submodule_prefix, "%s%s/", prefix, ce->name);
767                 git_dir = read_gitfile(submodule_git_dir.buf);
768                 if (!git_dir)
769                         git_dir = submodule_git_dir.buf;
770                 if (is_directory(git_dir)) {
771                         if (!quiet)
772                                 printf("Fetching submodule %s%s\n", prefix, ce->name);
773                         cp.dir = submodule_path.buf;
774                         argv_array_push(&argv, default_argv);
775                         argv_array_push(&argv, "--submodule-prefix");
776                         argv_array_push(&argv, submodule_prefix.buf);
777                         cp.argv = argv.argv;
778                         if (run_command(&cp))
779                                 result = 1;
780                         argv_array_pop(&argv);
781                         argv_array_pop(&argv);
782                         argv_array_pop(&argv);
783                 }
784                 strbuf_release(&submodule_path);
785                 strbuf_release(&submodule_git_dir);
786                 strbuf_release(&submodule_prefix);
787         }
788         argv_array_clear(&argv);
789 out:
790         string_list_clear(&changed_submodule_paths, 1);
791         return result;
792 }
793
794 unsigned is_submodule_modified(const char *path, int ignore_untracked)
795 {
796         ssize_t len;
797         struct child_process cp;
798         const char *argv[] = {
799                 "status",
800                 "--porcelain",
801                 NULL,
802                 NULL,
803         };
804         struct strbuf buf = STRBUF_INIT;
805         unsigned dirty_submodule = 0;
806         const char *line, *next_line;
807         const char *git_dir;
808
809         strbuf_addf(&buf, "%s/.git", path);
810         git_dir = read_gitfile(buf.buf);
811         if (!git_dir)
812                 git_dir = buf.buf;
813         if (!is_directory(git_dir)) {
814                 strbuf_release(&buf);
815                 /* The submodule is not checked out, so it is not modified */
816                 return 0;
817
818         }
819         strbuf_reset(&buf);
820
821         if (ignore_untracked)
822                 argv[2] = "-uno";
823
824         memset(&cp, 0, sizeof(cp));
825         cp.argv = argv;
826         cp.env = local_repo_env;
827         cp.git_cmd = 1;
828         cp.no_stdin = 1;
829         cp.out = -1;
830         cp.dir = path;
831         if (start_command(&cp))
832                 die("Could not run 'git status --porcelain' in submodule %s", path);
833
834         len = strbuf_read(&buf, cp.out, 1024);
835         line = buf.buf;
836         while (len > 2) {
837                 if ((line[0] == '?') && (line[1] == '?')) {
838                         dirty_submodule |= DIRTY_SUBMODULE_UNTRACKED;
839                         if (dirty_submodule & DIRTY_SUBMODULE_MODIFIED)
840                                 break;
841                 } else {
842                         dirty_submodule |= DIRTY_SUBMODULE_MODIFIED;
843                         if (ignore_untracked ||
844                             (dirty_submodule & DIRTY_SUBMODULE_UNTRACKED))
845                                 break;
846                 }
847                 next_line = strchr(line, '\n');
848                 if (!next_line)
849                         break;
850                 next_line++;
851                 len -= (next_line - line);
852                 line = next_line;
853         }
854         close(cp.out);
855
856         if (finish_command(&cp))
857                 die("'git status --porcelain' failed in submodule %s", path);
858
859         strbuf_release(&buf);
860         return dirty_submodule;
861 }
862
863 int submodule_uses_gitfile(const char *path)
864 {
865         struct child_process cp;
866         const char *argv[] = {
867                 "submodule",
868                 "foreach",
869                 "--quiet",
870                 "--recursive",
871                 "test -f .git",
872                 NULL,
873         };
874         struct strbuf buf = STRBUF_INIT;
875         const char *git_dir;
876
877         strbuf_addf(&buf, "%s/.git", path);
878         git_dir = read_gitfile(buf.buf);
879         if (!git_dir) {
880                 strbuf_release(&buf);
881                 return 0;
882         }
883         strbuf_release(&buf);
884
885         /* Now test that all nested submodules use a gitfile too */
886         memset(&cp, 0, sizeof(cp));
887         cp.argv = argv;
888         cp.env = local_repo_env;
889         cp.git_cmd = 1;
890         cp.no_stdin = 1;
891         cp.no_stderr = 1;
892         cp.no_stdout = 1;
893         cp.dir = path;
894         if (run_command(&cp))
895                 return 0;
896
897         return 1;
898 }
899
900 int ok_to_remove_submodule(const char *path)
901 {
902         struct stat st;
903         ssize_t len;
904         struct child_process cp;
905         const char *argv[] = {
906                 "status",
907                 "--porcelain",
908                 "-u",
909                 "--ignore-submodules=none",
910                 NULL,
911         };
912         struct strbuf buf = STRBUF_INIT;
913         int ok_to_remove = 1;
914
915         if ((lstat(path, &st) < 0) || is_empty_dir(path))
916                 return 1;
917
918         if (!submodule_uses_gitfile(path))
919                 return 0;
920
921         memset(&cp, 0, sizeof(cp));
922         cp.argv = argv;
923         cp.env = local_repo_env;
924         cp.git_cmd = 1;
925         cp.no_stdin = 1;
926         cp.out = -1;
927         cp.dir = path;
928         if (start_command(&cp))
929                 die("Could not run 'git status --porcelain -uall --ignore-submodules=none' in submodule %s", path);
930
931         len = strbuf_read(&buf, cp.out, 1024);
932         if (len > 2)
933                 ok_to_remove = 0;
934         close(cp.out);
935
936         if (finish_command(&cp))
937                 die("'git status --porcelain -uall --ignore-submodules=none' failed in submodule %s", path);
938
939         strbuf_release(&buf);
940         return ok_to_remove;
941 }
942
943 static int find_first_merges(struct object_array *result, const char *path,
944                 struct commit *a, struct commit *b)
945 {
946         int i, j;
947         struct object_array merges = OBJECT_ARRAY_INIT;
948         struct commit *commit;
949         int contains_another;
950
951         char merged_revision[42];
952         const char *rev_args[] = { "rev-list", "--merges", "--ancestry-path",
953                                    "--all", merged_revision, NULL };
954         struct rev_info revs;
955         struct setup_revision_opt rev_opts;
956
957         memset(result, 0, sizeof(struct object_array));
958         memset(&rev_opts, 0, sizeof(rev_opts));
959
960         /* get all revisions that merge commit a */
961         snprintf(merged_revision, sizeof(merged_revision), "^%s",
962                         sha1_to_hex(a->object.sha1));
963         init_revisions(&revs, NULL);
964         rev_opts.submodule = path;
965         setup_revisions(ARRAY_SIZE(rev_args)-1, rev_args, &revs, &rev_opts);
966
967         /* save all revisions from the above list that contain b */
968         if (prepare_revision_walk(&revs))
969                 die("revision walk setup failed");
970         while ((commit = get_revision(&revs)) != NULL) {
971                 struct object *o = &(commit->object);
972                 if (in_merge_bases(b, commit))
973                         add_object_array(o, NULL, &merges);
974         }
975         reset_revision_walk();
976
977         /* Now we've got all merges that contain a and b. Prune all
978          * merges that contain another found merge and save them in
979          * result.
980          */
981         for (i = 0; i < merges.nr; i++) {
982                 struct commit *m1 = (struct commit *) merges.objects[i].item;
983
984                 contains_another = 0;
985                 for (j = 0; j < merges.nr; j++) {
986                         struct commit *m2 = (struct commit *) merges.objects[j].item;
987                         if (i != j && in_merge_bases(m2, m1)) {
988                                 contains_another = 1;
989                                 break;
990                         }
991                 }
992
993                 if (!contains_another)
994                         add_object_array(merges.objects[i].item, NULL, result);
995         }
996
997         free(merges.objects);
998         return result->nr;
999 }
1000
1001 static void print_commit(struct commit *commit)
1002 {
1003         struct strbuf sb = STRBUF_INIT;
1004         struct pretty_print_context ctx = {0};
1005         ctx.date_mode = DATE_NORMAL;
1006         format_commit_message(commit, " %h: %m %s", &sb, &ctx);
1007         fprintf(stderr, "%s\n", sb.buf);
1008         strbuf_release(&sb);
1009 }
1010
1011 #define MERGE_WARNING(path, msg) \
1012         warning("Failed to merge submodule %s (%s)", path, msg);
1013
1014 int merge_submodule(unsigned char result[20], const char *path,
1015                     const unsigned char base[20], const unsigned char a[20],
1016                     const unsigned char b[20], int search)
1017 {
1018         struct commit *commit_base, *commit_a, *commit_b;
1019         int parent_count;
1020         struct object_array merges;
1021
1022         int i;
1023
1024         /* store a in result in case we fail */
1025         hashcpy(result, a);
1026
1027         /* we can not handle deletion conflicts */
1028         if (is_null_sha1(base))
1029                 return 0;
1030         if (is_null_sha1(a))
1031                 return 0;
1032         if (is_null_sha1(b))
1033                 return 0;
1034
1035         if (add_submodule_odb(path)) {
1036                 MERGE_WARNING(path, "not checked out");
1037                 return 0;
1038         }
1039
1040         if (!(commit_base = lookup_commit_reference(base)) ||
1041             !(commit_a = lookup_commit_reference(a)) ||
1042             !(commit_b = lookup_commit_reference(b))) {
1043                 MERGE_WARNING(path, "commits not present");
1044                 return 0;
1045         }
1046
1047         /* check whether both changes are forward */
1048         if (!in_merge_bases(commit_base, commit_a) ||
1049             !in_merge_bases(commit_base, commit_b)) {
1050                 MERGE_WARNING(path, "commits don't follow merge-base");
1051                 return 0;
1052         }
1053
1054         /* Case #1: a is contained in b or vice versa */
1055         if (in_merge_bases(commit_a, commit_b)) {
1056                 hashcpy(result, b);
1057                 return 1;
1058         }
1059         if (in_merge_bases(commit_b, commit_a)) {
1060                 hashcpy(result, a);
1061                 return 1;
1062         }
1063
1064         /*
1065          * Case #2: There are one or more merges that contain a and b in
1066          * the submodule. If there is only one, then present it as a
1067          * suggestion to the user, but leave it marked unmerged so the
1068          * user needs to confirm the resolution.
1069          */
1070
1071         /* Skip the search if makes no sense to the calling context.  */
1072         if (!search)
1073                 return 0;
1074
1075         /* find commit which merges them */
1076         parent_count = find_first_merges(&merges, path, commit_a, commit_b);
1077         switch (parent_count) {
1078         case 0:
1079                 MERGE_WARNING(path, "merge following commits not found");
1080                 break;
1081
1082         case 1:
1083                 MERGE_WARNING(path, "not fast-forward");
1084                 fprintf(stderr, "Found a possible merge resolution "
1085                                 "for the submodule:\n");
1086                 print_commit((struct commit *) merges.objects[0].item);
1087                 fprintf(stderr,
1088                         "If this is correct simply add it to the index "
1089                         "for example\n"
1090                         "by using:\n\n"
1091                         "  git update-index --cacheinfo 160000 %s \"%s\"\n\n"
1092                         "which will accept this suggestion.\n",
1093                         sha1_to_hex(merges.objects[0].item->sha1), path);
1094                 break;
1095
1096         default:
1097                 MERGE_WARNING(path, "multiple merges found");
1098                 for (i = 0; i < merges.nr; i++)
1099                         print_commit((struct commit *) merges.objects[i].item);
1100         }
1101
1102         free(merges.objects);
1103         return 0;
1104 }
1105
1106 /* Update gitfile and core.worktree setting to connect work tree and git dir */
1107 void connect_work_tree_and_git_dir(const char *work_tree, const char *git_dir)
1108 {
1109         struct strbuf file_name = STRBUF_INIT;
1110         struct strbuf rel_path = STRBUF_INIT;
1111         const char *real_work_tree = xstrdup(real_path(work_tree));
1112         FILE *fp;
1113
1114         /* Update gitfile */
1115         strbuf_addf(&file_name, "%s/.git", work_tree);
1116         fp = fopen(file_name.buf, "w");
1117         if (!fp)
1118                 die(_("Could not create git link %s"), file_name.buf);
1119         fprintf(fp, "gitdir: %s\n", relative_path(git_dir, real_work_tree,
1120                                                   &rel_path));
1121         fclose(fp);
1122
1123         /* Update core.worktree setting */
1124         strbuf_reset(&file_name);
1125         strbuf_addf(&file_name, "%s/config", git_dir);
1126         if (git_config_set_in_file(file_name.buf, "core.worktree",
1127                                    relative_path(real_work_tree, git_dir,
1128                                                  &rel_path)))
1129                 die(_("Could not set core.worktree in %s"),
1130                     file_name.buf);
1131
1132         strbuf_release(&file_name);
1133         strbuf_release(&rel_path);
1134         free((void *)real_work_tree);
1135 }