Andrew's git / gitweb.git / submodule.c
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submodule.con commit Update draft release notes to 1.8.2 (2f19ada)
   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
  14static struct string_list config_name_for_path;
  15static struct string_list config_fetch_recurse_submodules_for_name;
  16static struct string_list config_ignore_for_name;
  17static int config_fetch_recurse_submodules = RECURSE_SUBMODULES_ON_DEMAND;
  18static struct string_list changed_submodule_paths;
  19static int initialized_fetch_ref_tips;
  20static struct sha1_array ref_tips_before_fetch;
  21static struct sha1_array ref_tips_after_fetch;
  22
  23/*
  24 * The following flag is set if the .gitmodules file is unmerged. We then
  25 * disable recursion for all submodules where .git/config doesn't have a
  26 * matching config entry because we can't guess what might be configured in
  27 * .gitmodules unless the user resolves the conflict. When a command line
  28 * option is given (which always overrides configuration) this flag will be
  29 * ignored.
  30 */
  31static int gitmodules_is_unmerged;
  32
  33static int add_submodule_odb(const char *path)
  34{
  35        struct strbuf objects_directory = STRBUF_INIT;
  36        struct alternate_object_database *alt_odb;
  37        int ret = 0;
  38        const char *git_dir;
  39
  40        strbuf_addf(&objects_directory, "%s/.git", path);
  41        git_dir = read_gitfile(objects_directory.buf);
  42        if (git_dir) {
  43                strbuf_reset(&objects_directory);
  44                strbuf_addstr(&objects_directory, git_dir);
  45        }
  46        strbuf_addstr(&objects_directory, "/objects/");
  47        if (!is_directory(objects_directory.buf)) {
  48                ret = -1;
  49                goto done;
  50        }
  51        /* avoid adding it twice */
  52        for (alt_odb = alt_odb_list; alt_odb; alt_odb = alt_odb->next)
  53                if (alt_odb->name - alt_odb->base == objects_directory.len &&
  54                                !strncmp(alt_odb->base, objects_directory.buf,
  55                                        objects_directory.len))
  56                        goto done;
  57
  58        alt_odb = xmalloc(objects_directory.len + 42 + sizeof(*alt_odb));
  59        alt_odb->next = alt_odb_list;
  60        strcpy(alt_odb->base, objects_directory.buf);
  61        alt_odb->name = alt_odb->base + objects_directory.len;
  62        alt_odb->name[2] = '/';
  63        alt_odb->name[40] = '\0';
  64        alt_odb->name[41] = '\0';
  65        alt_odb_list = alt_odb;
  66
  67        /* add possible alternates from the submodule */
  68        read_info_alternates(objects_directory.buf, 0);
  69        prepare_alt_odb();
  70done:
  71        strbuf_release(&objects_directory);
  72        return ret;
  73}
  74
  75void set_diffopt_flags_from_submodule_config(struct diff_options *diffopt,
  76                                             const char *path)
  77{
  78        struct string_list_item *path_option, *ignore_option;
  79        path_option = unsorted_string_list_lookup(&config_name_for_path, path);
  80        if (path_option) {
  81                ignore_option = unsorted_string_list_lookup(&config_ignore_for_name, path_option->util);
  82                if (ignore_option)
  83                        handle_ignore_submodules_arg(diffopt, ignore_option->util);
  84                else if (gitmodules_is_unmerged)
  85                        DIFF_OPT_SET(diffopt, IGNORE_SUBMODULES);
  86        }
  87}
  88
  89int submodule_config(const char *var, const char *value, void *cb)
  90{
  91        if (!prefixcmp(var, "submodule."))
  92                return parse_submodule_config_option(var, value);
  93        else if (!strcmp(var, "fetch.recursesubmodules")) {
  94                config_fetch_recurse_submodules = parse_fetch_recurse_submodules_arg(var, value);
  95                return 0;
  96        }
  97        return 0;
  98}
  99
 100void gitmodules_config(void)
 101{
 102        const char *work_tree = get_git_work_tree();
 103        if (work_tree) {
 104                struct strbuf gitmodules_path = STRBUF_INIT;
 105                int pos;
 106                strbuf_addstr(&gitmodules_path, work_tree);
 107                strbuf_addstr(&gitmodules_path, "/.gitmodules");
 108                if (read_cache() < 0)
 109                        die("index file corrupt");
 110                pos = cache_name_pos(".gitmodules", 11);
 111                if (pos < 0) { /* .gitmodules not found or isn't merged */
 112                        pos = -1 - pos;
 113                        if (active_nr > pos) {  /* there is a .gitmodules */
 114                                const struct cache_entry *ce = active_cache[pos];
 115                                if (ce_namelen(ce) == 11 &&
 116                                    !memcmp(ce->name, ".gitmodules", 11))
 117                                        gitmodules_is_unmerged = 1;
 118                        }
 119                }
 120
 121                if (!gitmodules_is_unmerged)
 122                        git_config_from_file(submodule_config, gitmodules_path.buf, NULL);
 123                strbuf_release(&gitmodules_path);
 124        }
 125}
 126
 127int parse_submodule_config_option(const char *var, const char *value)
 128{
 129        struct string_list_item *config;
 130        const char *name, *key;
 131        int namelen;
 132
 133        if (parse_config_key(var, "submodule", &name, &namelen, &key) < 0 || !name)
 134                return 0;
 135
 136        if (!strcmp(key, "path")) {
 137                config = unsorted_string_list_lookup(&config_name_for_path, value);
 138                if (config)
 139                        free(config->util);
 140                else
 141                        config = string_list_append(&config_name_for_path, xstrdup(value));
 142                config->util = xmemdupz(name, namelen);
 143        } else if (!strcmp(key, "fetchrecursesubmodules")) {
 144                char *name_cstr = xmemdupz(name, namelen);
 145                config = unsorted_string_list_lookup(&config_fetch_recurse_submodules_for_name, name_cstr);
 146                if (!config)
 147                        config = string_list_append(&config_fetch_recurse_submodules_for_name, name_cstr);
 148                else
 149                        free(name_cstr);
 150                config->util = (void *)(intptr_t)parse_fetch_recurse_submodules_arg(var, value);
 151        } else if (!strcmp(key, "ignore")) {
 152                char *name_cstr;
 153
 154                if (strcmp(value, "untracked") && strcmp(value, "dirty") &&
 155                    strcmp(value, "all") && strcmp(value, "none")) {
 156                        warning("Invalid parameter \"%s\" for config option \"submodule.%s.ignore\"", value, var);
 157                        return 0;
 158                }
 159
 160                name_cstr = xmemdupz(name, namelen);
 161                config = unsorted_string_list_lookup(&config_ignore_for_name, name_cstr);
 162                if (config) {
 163                        free(config->util);
 164                        free(name_cstr);
 165                } else
 166                        config = string_list_append(&config_ignore_for_name, name_cstr);
 167                config->util = xstrdup(value);
 168                return 0;
 169        }
 170        return 0;
 171}
 172
 173void handle_ignore_submodules_arg(struct diff_options *diffopt,
 174                                  const char *arg)
 175{
 176        DIFF_OPT_CLR(diffopt, IGNORE_SUBMODULES);
 177        DIFF_OPT_CLR(diffopt, IGNORE_UNTRACKED_IN_SUBMODULES);
 178        DIFF_OPT_CLR(diffopt, IGNORE_DIRTY_SUBMODULES);
 179
 180        if (!strcmp(arg, "all"))
 181                DIFF_OPT_SET(diffopt, IGNORE_SUBMODULES);
 182        else if (!strcmp(arg, "untracked"))
 183                DIFF_OPT_SET(diffopt, IGNORE_UNTRACKED_IN_SUBMODULES);
 184        else if (!strcmp(arg, "dirty"))
 185                DIFF_OPT_SET(diffopt, IGNORE_DIRTY_SUBMODULES);
 186        else if (strcmp(arg, "none"))
 187                die("bad --ignore-submodules argument: %s", arg);
 188}
 189
 190static int prepare_submodule_summary(struct rev_info *rev, const char *path,
 191                struct commit *left, struct commit *right,
 192                int *fast_forward, int *fast_backward)
 193{
 194        struct commit_list *merge_bases, *list;
 195
 196        init_revisions(rev, NULL);
 197        setup_revisions(0, NULL, rev, NULL);
 198        rev->left_right = 1;
 199        rev->first_parent_only = 1;
 200        left->object.flags |= SYMMETRIC_LEFT;
 201        add_pending_object(rev, &left->object, path);
 202        add_pending_object(rev, &right->object, path);
 203        merge_bases = get_merge_bases(left, right, 1);
 204        if (merge_bases) {
 205                if (merge_bases->item == left)
 206                        *fast_forward = 1;
 207                else if (merge_bases->item == right)
 208                        *fast_backward = 1;
 209        }
 210        for (list = merge_bases; list; list = list->next) {
 211                list->item->object.flags |= UNINTERESTING;
 212                add_pending_object(rev, &list->item->object,
 213                        sha1_to_hex(list->item->object.sha1));
 214        }
 215        return prepare_revision_walk(rev);
 216}
 217
 218static void print_submodule_summary(struct rev_info *rev, FILE *f,
 219                const char *del, const char *add, const char *reset)
 220{
 221        static const char format[] = "  %m %s";
 222        struct strbuf sb = STRBUF_INIT;
 223        struct commit *commit;
 224
 225        while ((commit = get_revision(rev))) {
 226                struct pretty_print_context ctx = {0};
 227                ctx.date_mode = rev->date_mode;
 228                strbuf_setlen(&sb, 0);
 229                if (commit->object.flags & SYMMETRIC_LEFT) {
 230                        if (del)
 231                                strbuf_addstr(&sb, del);
 232                }
 233                else if (add)
 234                        strbuf_addstr(&sb, add);
 235                format_commit_message(commit, format, &sb, &ctx);
 236                if (reset)
 237                        strbuf_addstr(&sb, reset);
 238                strbuf_addch(&sb, '\n');
 239                fprintf(f, "%s", sb.buf);
 240        }
 241        strbuf_release(&sb);
 242}
 243
 244int parse_fetch_recurse_submodules_arg(const char *opt, const char *arg)
 245{
 246        switch (git_config_maybe_bool(opt, arg)) {
 247        case 1:
 248                return RECURSE_SUBMODULES_ON;
 249        case 0:
 250                return RECURSE_SUBMODULES_OFF;
 251        default:
 252                if (!strcmp(arg, "on-demand"))
 253                        return RECURSE_SUBMODULES_ON_DEMAND;
 254                die("bad %s argument: %s", opt, arg);
 255        }
 256}
 257
 258void show_submodule_summary(FILE *f, const char *path,
 259                unsigned char one[20], unsigned char two[20],
 260                unsigned dirty_submodule, const char *meta,
 261                const char *del, const char *add, const char *reset)
 262{
 263        struct rev_info rev;
 264        struct commit *left = left, *right = right;
 265        const char *message = NULL;
 266        struct strbuf sb = STRBUF_INIT;
 267        int fast_forward = 0, fast_backward = 0;
 268
 269        if (is_null_sha1(two))
 270                message = "(submodule deleted)";
 271        else if (add_submodule_odb(path))
 272                message = "(not checked out)";
 273        else if (is_null_sha1(one))
 274                message = "(new submodule)";
 275        else if (!(left = lookup_commit_reference(one)) ||
 276                 !(right = lookup_commit_reference(two)))
 277                message = "(commits not present)";
 278
 279        if (!message &&
 280            prepare_submodule_summary(&rev, path, left, right,
 281                                        &fast_forward, &fast_backward))
 282                message = "(revision walker failed)";
 283
 284        if (dirty_submodule & DIRTY_SUBMODULE_UNTRACKED)
 285                fprintf(f, "Submodule %s contains untracked content\n", path);
 286        if (dirty_submodule & DIRTY_SUBMODULE_MODIFIED)
 287                fprintf(f, "Submodule %s contains modified content\n", path);
 288
 289        if (!hashcmp(one, two)) {
 290                strbuf_release(&sb);
 291                return;
 292        }
 293
 294        strbuf_addf(&sb, "%sSubmodule %s %s..", meta, path,
 295                        find_unique_abbrev(one, DEFAULT_ABBREV));
 296        if (!fast_backward && !fast_forward)
 297                strbuf_addch(&sb, '.');
 298        strbuf_addf(&sb, "%s", find_unique_abbrev(two, DEFAULT_ABBREV));
 299        if (message)
 300                strbuf_addf(&sb, " %s%s\n", message, reset);
 301        else
 302                strbuf_addf(&sb, "%s:%s\n", fast_backward ? " (rewind)" : "", reset);
 303        fwrite(sb.buf, sb.len, 1, f);
 304
 305        if (!message) {
 306                print_submodule_summary(&rev, f, del, add, reset);
 307                clear_commit_marks(left, ~0);
 308                clear_commit_marks(right, ~0);
 309        }
 310
 311        strbuf_release(&sb);
 312}
 313
 314void set_config_fetch_recurse_submodules(int value)
 315{
 316        config_fetch_recurse_submodules = value;
 317}
 318
 319static int has_remote(const char *refname, const unsigned char *sha1, int flags, void *cb_data)
 320{
 321        return 1;
 322}
 323
 324static int submodule_needs_pushing(const char *path, const unsigned char sha1[20])
 325{
 326        if (add_submodule_odb(path) || !lookup_commit_reference(sha1))
 327                return 0;
 328
 329        if (for_each_remote_ref_submodule(path, has_remote, NULL) > 0) {
 330                struct child_process cp;
 331                const char *argv[] = {"rev-list", NULL, "--not", "--remotes", "-n", "1" , NULL};
 332                struct strbuf buf = STRBUF_INIT;
 333                int needs_pushing = 0;
 334
 335                argv[1] = sha1_to_hex(sha1);
 336                memset(&cp, 0, sizeof(cp));
 337                cp.argv = argv;
 338                cp.env = local_repo_env;
 339                cp.git_cmd = 1;
 340                cp.no_stdin = 1;
 341                cp.out = -1;
 342                cp.dir = path;
 343                if (start_command(&cp))
 344                        die("Could not run 'git rev-list %s --not --remotes -n 1' command in submodule %s",
 345                                sha1_to_hex(sha1), path);
 346                if (strbuf_read(&buf, cp.out, 41))
 347                        needs_pushing = 1;
 348                finish_command(&cp);
 349                close(cp.out);
 350                strbuf_release(&buf);
 351                return needs_pushing;
 352        }
 353
 354        return 0;
 355}
 356
 357static void collect_submodules_from_diff(struct diff_queue_struct *q,
 358                                         struct diff_options *options,
 359                                         void *data)
 360{
 361        int i;
 362        struct string_list *needs_pushing = data;
 363
 364        for (i = 0; i < q->nr; i++) {
 365                struct diff_filepair *p = q->queue[i];
 366                if (!S_ISGITLINK(p->two->mode))
 367                        continue;
 368                if (submodule_needs_pushing(p->two->path, p->two->sha1))
 369                        string_list_insert(needs_pushing, p->two->path);
 370        }
 371}
 372
 373static void find_unpushed_submodule_commits(struct commit *commit,
 374                struct string_list *needs_pushing)
 375{
 376        struct rev_info rev;
 377
 378        init_revisions(&rev, NULL);
 379        rev.diffopt.output_format |= DIFF_FORMAT_CALLBACK;
 380        rev.diffopt.format_callback = collect_submodules_from_diff;
 381        rev.diffopt.format_callback_data = needs_pushing;
 382        diff_tree_combined_merge(commit, 1, &rev);
 383}
 384
 385int find_unpushed_submodules(unsigned char new_sha1[20],
 386                const char *remotes_name, struct string_list *needs_pushing)
 387{
 388        struct rev_info rev;
 389        struct commit *commit;
 390        const char *argv[] = {NULL, NULL, "--not", "NULL", NULL};
 391        int argc = ARRAY_SIZE(argv) - 1;
 392        char *sha1_copy;
 393
 394        struct strbuf remotes_arg = STRBUF_INIT;
 395
 396        strbuf_addf(&remotes_arg, "--remotes=%s", remotes_name);
 397        init_revisions(&rev, NULL);
 398        sha1_copy = xstrdup(sha1_to_hex(new_sha1));
 399        argv[1] = sha1_copy;
 400        argv[3] = remotes_arg.buf;
 401        setup_revisions(argc, argv, &rev, NULL);
 402        if (prepare_revision_walk(&rev))
 403                die("revision walk setup failed");
 404
 405        while ((commit = get_revision(&rev)) != NULL)
 406                find_unpushed_submodule_commits(commit, needs_pushing);
 407
 408        reset_revision_walk();
 409        free(sha1_copy);
 410        strbuf_release(&remotes_arg);
 411
 412        return needs_pushing->nr;
 413}
 414
 415static int push_submodule(const char *path)
 416{
 417        if (add_submodule_odb(path))
 418                return 1;
 419
 420        if (for_each_remote_ref_submodule(path, has_remote, NULL) > 0) {
 421                struct child_process cp;
 422                const char *argv[] = {"push", NULL};
 423
 424                memset(&cp, 0, sizeof(cp));
 425                cp.argv = argv;
 426                cp.env = local_repo_env;
 427                cp.git_cmd = 1;
 428                cp.no_stdin = 1;
 429                cp.dir = path;
 430                if (run_command(&cp))
 431                        return 0;
 432                close(cp.out);
 433        }
 434
 435        return 1;
 436}
 437
 438int push_unpushed_submodules(unsigned char new_sha1[20], const char *remotes_name)
 439{
 440        int i, ret = 1;
 441        struct string_list needs_pushing;
 442
 443        memset(&needs_pushing, 0, sizeof(struct string_list));
 444        needs_pushing.strdup_strings = 1;
 445
 446        if (!find_unpushed_submodules(new_sha1, remotes_name, &needs_pushing))
 447                return 1;
 448
 449        for (i = 0; i < needs_pushing.nr; i++) {
 450                const char *path = needs_pushing.items[i].string;
 451                fprintf(stderr, "Pushing submodule '%s'\n", path);
 452                if (!push_submodule(path)) {
 453                        fprintf(stderr, "Unable to push submodule '%s'\n", path);
 454                        ret = 0;
 455                }
 456        }
 457
 458        string_list_clear(&needs_pushing, 0);
 459
 460        return ret;
 461}
 462
 463static int is_submodule_commit_present(const char *path, unsigned char sha1[20])
 464{
 465        int is_present = 0;
 466        if (!add_submodule_odb(path) && lookup_commit_reference(sha1)) {
 467                /* Even if the submodule is checked out and the commit is
 468                 * present, make sure it is reachable from a ref. */
 469                struct child_process cp;
 470                const char *argv[] = {"rev-list", "-n", "1", NULL, "--not", "--all", NULL};
 471                struct strbuf buf = STRBUF_INIT;
 472
 473                argv[3] = sha1_to_hex(sha1);
 474                memset(&cp, 0, sizeof(cp));
 475                cp.argv = argv;
 476                cp.env = local_repo_env;
 477                cp.git_cmd = 1;
 478                cp.no_stdin = 1;
 479                cp.out = -1;
 480                cp.dir = path;
 481                if (!run_command(&cp) && !strbuf_read(&buf, cp.out, 1024))
 482                        is_present = 1;
 483
 484                close(cp.out);
 485                strbuf_release(&buf);
 486        }
 487        return is_present;
 488}
 489
 490static void submodule_collect_changed_cb(struct diff_queue_struct *q,
 491                                         struct diff_options *options,
 492                                         void *data)
 493{
 494        int i;
 495        for (i = 0; i < q->nr; i++) {
 496                struct diff_filepair *p = q->queue[i];
 497                if (!S_ISGITLINK(p->two->mode))
 498                        continue;
 499
 500                if (S_ISGITLINK(p->one->mode)) {
 501                        /* NEEDSWORK: We should honor the name configured in
 502                         * the .gitmodules file of the commit we are examining
 503                         * here to be able to correctly follow submodules
 504                         * being moved around. */
 505                        struct string_list_item *path;
 506                        path = unsorted_string_list_lookup(&changed_submodule_paths, p->two->path);
 507                        if (!path && !is_submodule_commit_present(p->two->path, p->two->sha1))
 508                                string_list_append(&changed_submodule_paths, xstrdup(p->two->path));
 509                } else {
 510                        /* Submodule is new or was moved here */
 511                        /* NEEDSWORK: When the .git directories of submodules
 512                         * live inside the superprojects .git directory some
 513                         * day we should fetch new submodules directly into
 514                         * that location too when config or options request
 515                         * that so they can be checked out from there. */
 516                        continue;
 517                }
 518        }
 519}
 520
 521static int add_sha1_to_array(const char *ref, const unsigned char *sha1,
 522                             int flags, void *data)
 523{
 524        sha1_array_append(data, sha1);
 525        return 0;
 526}
 527
 528void check_for_new_submodule_commits(unsigned char new_sha1[20])
 529{
 530        if (!initialized_fetch_ref_tips) {
 531                for_each_ref(add_sha1_to_array, &ref_tips_before_fetch);
 532                initialized_fetch_ref_tips = 1;
 533        }
 534
 535        sha1_array_append(&ref_tips_after_fetch, new_sha1);
 536}
 537
 538static void add_sha1_to_argv(const unsigned char sha1[20], void *data)
 539{
 540        argv_array_push(data, sha1_to_hex(sha1));
 541}
 542
 543static void calculate_changed_submodule_paths(void)
 544{
 545        struct rev_info rev;
 546        struct commit *commit;
 547        struct argv_array argv = ARGV_ARRAY_INIT;
 548
 549        /* No need to check if there are no submodules configured */
 550        if (!config_name_for_path.nr)
 551                return;
 552
 553        init_revisions(&rev, NULL);
 554        argv_array_push(&argv, "--"); /* argv[0] program name */
 555        sha1_array_for_each_unique(&ref_tips_after_fetch,
 556                                   add_sha1_to_argv, &argv);
 557        argv_array_push(&argv, "--not");
 558        sha1_array_for_each_unique(&ref_tips_before_fetch,
 559                                   add_sha1_to_argv, &argv);
 560        setup_revisions(argv.argc, argv.argv, &rev, NULL);
 561        if (prepare_revision_walk(&rev))
 562                die("revision walk setup failed");
 563
 564        /*
 565         * Collect all submodules (whether checked out or not) for which new
 566         * commits have been recorded upstream in "changed_submodule_paths".
 567         */
 568        while ((commit = get_revision(&rev))) {
 569                struct commit_list *parent = commit->parents;
 570                while (parent) {
 571                        struct diff_options diff_opts;
 572                        diff_setup(&diff_opts);
 573                        DIFF_OPT_SET(&diff_opts, RECURSIVE);
 574                        diff_opts.output_format |= DIFF_FORMAT_CALLBACK;
 575                        diff_opts.format_callback = submodule_collect_changed_cb;
 576                        diff_setup_done(&diff_opts);
 577                        diff_tree_sha1(parent->item->object.sha1, commit->object.sha1, "", &diff_opts);
 578                        diffcore_std(&diff_opts);
 579                        diff_flush(&diff_opts);
 580                        parent = parent->next;
 581                }
 582        }
 583
 584        argv_array_clear(&argv);
 585        sha1_array_clear(&ref_tips_before_fetch);
 586        sha1_array_clear(&ref_tips_after_fetch);
 587        initialized_fetch_ref_tips = 0;
 588}
 589
 590int fetch_populated_submodules(const struct argv_array *options,
 591                               const char *prefix, int command_line_option,
 592                               int quiet)
 593{
 594        int i, result = 0;
 595        struct child_process cp;
 596        struct argv_array argv = ARGV_ARRAY_INIT;
 597        struct string_list_item *name_for_path;
 598        const char *work_tree = get_git_work_tree();
 599        if (!work_tree)
 600                goto out;
 601
 602        if (!the_index.initialized)
 603                if (read_cache() < 0)
 604                        die("index file corrupt");
 605
 606        argv_array_push(&argv, "fetch");
 607        for (i = 0; i < options->argc; i++)
 608                argv_array_push(&argv, options->argv[i]);
 609        argv_array_push(&argv, "--recurse-submodules-default");
 610        /* default value, "--submodule-prefix" and its value are added later */
 611
 612        memset(&cp, 0, sizeof(cp));
 613        cp.env = local_repo_env;
 614        cp.git_cmd = 1;
 615        cp.no_stdin = 1;
 616
 617        calculate_changed_submodule_paths();
 618
 619        for (i = 0; i < active_nr; i++) {
 620                struct strbuf submodule_path = STRBUF_INIT;
 621                struct strbuf submodule_git_dir = STRBUF_INIT;
 622                struct strbuf submodule_prefix = STRBUF_INIT;
 623                struct cache_entry *ce = active_cache[i];
 624                const char *git_dir, *name, *default_argv;
 625
 626                if (!S_ISGITLINK(ce->ce_mode))
 627                        continue;
 628
 629                name = ce->name;
 630                name_for_path = unsorted_string_list_lookup(&config_name_for_path, ce->name);
 631                if (name_for_path)
 632                        name = name_for_path->util;
 633
 634                default_argv = "yes";
 635                if (command_line_option == RECURSE_SUBMODULES_DEFAULT) {
 636                        struct string_list_item *fetch_recurse_submodules_option;
 637                        fetch_recurse_submodules_option = unsorted_string_list_lookup(&config_fetch_recurse_submodules_for_name, name);
 638                        if (fetch_recurse_submodules_option) {
 639                                if ((intptr_t)fetch_recurse_submodules_option->util == RECURSE_SUBMODULES_OFF)
 640                                        continue;
 641                                if ((intptr_t)fetch_recurse_submodules_option->util == RECURSE_SUBMODULES_ON_DEMAND) {
 642                                        if (!unsorted_string_list_lookup(&changed_submodule_paths, ce->name))
 643                                                continue;
 644                                        default_argv = "on-demand";
 645                                }
 646                        } else {
 647                                if ((config_fetch_recurse_submodules == RECURSE_SUBMODULES_OFF) ||
 648                                    gitmodules_is_unmerged)
 649                                        continue;
 650                                if (config_fetch_recurse_submodules == RECURSE_SUBMODULES_ON_DEMAND) {
 651                                        if (!unsorted_string_list_lookup(&changed_submodule_paths, ce->name))
 652                                                continue;
 653                                        default_argv = "on-demand";
 654                                }
 655                        }
 656                } else if (command_line_option == RECURSE_SUBMODULES_ON_DEMAND) {
 657                        if (!unsorted_string_list_lookup(&changed_submodule_paths, ce->name))
 658                                continue;
 659                        default_argv = "on-demand";
 660                }
 661
 662                strbuf_addf(&submodule_path, "%s/%s", work_tree, ce->name);
 663                strbuf_addf(&submodule_git_dir, "%s/.git", submodule_path.buf);
 664                strbuf_addf(&submodule_prefix, "%s%s/", prefix, ce->name);
 665                git_dir = read_gitfile(submodule_git_dir.buf);
 666                if (!git_dir)
 667                        git_dir = submodule_git_dir.buf;
 668                if (is_directory(git_dir)) {
 669                        if (!quiet)
 670                                printf("Fetching submodule %s%s\n", prefix, ce->name);
 671                        cp.dir = submodule_path.buf;
 672                        argv_array_push(&argv, default_argv);
 673                        argv_array_push(&argv, "--submodule-prefix");
 674                        argv_array_push(&argv, submodule_prefix.buf);
 675                        cp.argv = argv.argv;
 676                        if (run_command(&cp))
 677                                result = 1;
 678                        argv_array_pop(&argv);
 679                        argv_array_pop(&argv);
 680                        argv_array_pop(&argv);
 681                }
 682                strbuf_release(&submodule_path);
 683                strbuf_release(&submodule_git_dir);
 684                strbuf_release(&submodule_prefix);
 685        }
 686        argv_array_clear(&argv);
 687out:
 688        string_list_clear(&changed_submodule_paths, 1);
 689        return result;
 690}
 691
 692unsigned is_submodule_modified(const char *path, int ignore_untracked)
 693{
 694        ssize_t len;
 695        struct child_process cp;
 696        const char *argv[] = {
 697                "status",
 698                "--porcelain",
 699                NULL,
 700                NULL,
 701        };
 702        struct strbuf buf = STRBUF_INIT;
 703        unsigned dirty_submodule = 0;
 704        const char *line, *next_line;
 705        const char *git_dir;
 706
 707        strbuf_addf(&buf, "%s/.git", path);
 708        git_dir = read_gitfile(buf.buf);
 709        if (!git_dir)
 710                git_dir = buf.buf;
 711        if (!is_directory(git_dir)) {
 712                strbuf_release(&buf);
 713                /* The submodule is not checked out, so it is not modified */
 714                return 0;
 715
 716        }
 717        strbuf_reset(&buf);
 718
 719        if (ignore_untracked)
 720                argv[2] = "-uno";
 721
 722        memset(&cp, 0, sizeof(cp));
 723        cp.argv = argv;
 724        cp.env = local_repo_env;
 725        cp.git_cmd = 1;
 726        cp.no_stdin = 1;
 727        cp.out = -1;
 728        cp.dir = path;
 729        if (start_command(&cp))
 730                die("Could not run 'git status --porcelain' in submodule %s", path);
 731
 732        len = strbuf_read(&buf, cp.out, 1024);
 733        line = buf.buf;
 734        while (len > 2) {
 735                if ((line[0] == '?') && (line[1] == '?')) {
 736                        dirty_submodule |= DIRTY_SUBMODULE_UNTRACKED;
 737                        if (dirty_submodule & DIRTY_SUBMODULE_MODIFIED)
 738                                break;
 739                } else {
 740                        dirty_submodule |= DIRTY_SUBMODULE_MODIFIED;
 741                        if (ignore_untracked ||
 742                            (dirty_submodule & DIRTY_SUBMODULE_UNTRACKED))
 743                                break;
 744                }
 745                next_line = strchr(line, '\n');
 746                if (!next_line)
 747                        break;
 748                next_line++;
 749                len -= (next_line - line);
 750                line = next_line;
 751        }
 752        close(cp.out);
 753
 754        if (finish_command(&cp))
 755                die("'git status --porcelain' failed in submodule %s", path);
 756
 757        strbuf_release(&buf);
 758        return dirty_submodule;
 759}
 760
 761int submodule_uses_gitfile(const char *path)
 762{
 763        struct child_process cp;
 764        const char *argv[] = {
 765                "submodule",
 766                "foreach",
 767                "--quiet",
 768                "--recursive",
 769                "test -f .git",
 770                NULL,
 771        };
 772        struct strbuf buf = STRBUF_INIT;
 773        const char *git_dir;
 774
 775        strbuf_addf(&buf, "%s/.git", path);
 776        git_dir = read_gitfile(buf.buf);
 777        if (!git_dir) {
 778                strbuf_release(&buf);
 779                return 0;
 780        }
 781        strbuf_release(&buf);
 782
 783        /* Now test that all nested submodules use a gitfile too */
 784        memset(&cp, 0, sizeof(cp));
 785        cp.argv = argv;
 786        cp.env = local_repo_env;
 787        cp.git_cmd = 1;
 788        cp.no_stdin = 1;
 789        cp.no_stderr = 1;
 790        cp.no_stdout = 1;
 791        cp.dir = path;
 792        if (run_command(&cp))
 793                return 0;
 794
 795        return 1;
 796}
 797
 798int ok_to_remove_submodule(const char *path)
 799{
 800        struct stat st;
 801        ssize_t len;
 802        struct child_process cp;
 803        const char *argv[] = {
 804                "status",
 805                "--porcelain",
 806                "-u",
 807                "--ignore-submodules=none",
 808                NULL,
 809        };
 810        struct strbuf buf = STRBUF_INIT;
 811        int ok_to_remove = 1;
 812
 813        if ((lstat(path, &st) < 0) || is_empty_dir(path))
 814                return 1;
 815
 816        if (!submodule_uses_gitfile(path))
 817                return 0;
 818
 819        memset(&cp, 0, sizeof(cp));
 820        cp.argv = argv;
 821        cp.env = local_repo_env;
 822        cp.git_cmd = 1;
 823        cp.no_stdin = 1;
 824        cp.out = -1;
 825        cp.dir = path;
 826        if (start_command(&cp))
 827                die("Could not run 'git status --porcelain -uall --ignore-submodules=none' in submodule %s", path);
 828
 829        len = strbuf_read(&buf, cp.out, 1024);
 830        if (len > 2)
 831                ok_to_remove = 0;
 832        close(cp.out);
 833
 834        if (finish_command(&cp))
 835                die("'git status --porcelain -uall --ignore-submodules=none' failed in submodule %s", path);
 836
 837        strbuf_release(&buf);
 838        return ok_to_remove;
 839}
 840
 841static int find_first_merges(struct object_array *result, const char *path,
 842                struct commit *a, struct commit *b)
 843{
 844        int i, j;
 845        struct object_array merges;
 846        struct commit *commit;
 847        int contains_another;
 848
 849        char merged_revision[42];
 850        const char *rev_args[] = { "rev-list", "--merges", "--ancestry-path",
 851                                   "--all", merged_revision, NULL };
 852        struct rev_info revs;
 853        struct setup_revision_opt rev_opts;
 854
 855        memset(&merges, 0, sizeof(merges));
 856        memset(result, 0, sizeof(struct object_array));
 857        memset(&rev_opts, 0, sizeof(rev_opts));
 858
 859        /* get all revisions that merge commit a */
 860        snprintf(merged_revision, sizeof(merged_revision), "^%s",
 861                        sha1_to_hex(a->object.sha1));
 862        init_revisions(&revs, NULL);
 863        rev_opts.submodule = path;
 864        setup_revisions(sizeof(rev_args)/sizeof(char *)-1, rev_args, &revs, &rev_opts);
 865
 866        /* save all revisions from the above list that contain b */
 867        if (prepare_revision_walk(&revs))
 868                die("revision walk setup failed");
 869        while ((commit = get_revision(&revs)) != NULL) {
 870                struct object *o = &(commit->object);
 871                if (in_merge_bases(b, commit))
 872                        add_object_array(o, NULL, &merges);
 873        }
 874        reset_revision_walk();
 875
 876        /* Now we've got all merges that contain a and b. Prune all
 877         * merges that contain another found merge and save them in
 878         * result.
 879         */
 880        for (i = 0; i < merges.nr; i++) {
 881                struct commit *m1 = (struct commit *) merges.objects[i].item;
 882
 883                contains_another = 0;
 884                for (j = 0; j < merges.nr; j++) {
 885                        struct commit *m2 = (struct commit *) merges.objects[j].item;
 886                        if (i != j && in_merge_bases(m2, m1)) {
 887                                contains_another = 1;
 888                                break;
 889                        }
 890                }
 891
 892                if (!contains_another)
 893                        add_object_array(merges.objects[i].item,
 894                                         merges.objects[i].name, result);
 895        }
 896
 897        free(merges.objects);
 898        return result->nr;
 899}
 900
 901static void print_commit(struct commit *commit)
 902{
 903        struct strbuf sb = STRBUF_INIT;
 904        struct pretty_print_context ctx = {0};
 905        ctx.date_mode = DATE_NORMAL;
 906        format_commit_message(commit, " %h: %m %s", &sb, &ctx);
 907        fprintf(stderr, "%s\n", sb.buf);
 908        strbuf_release(&sb);
 909}
 910
 911#define MERGE_WARNING(path, msg) \
 912        warning("Failed to merge submodule %s (%s)", path, msg);
 913
 914int merge_submodule(unsigned char result[20], const char *path,
 915                    const unsigned char base[20], const unsigned char a[20],
 916                    const unsigned char b[20], int search)
 917{
 918        struct commit *commit_base, *commit_a, *commit_b;
 919        int parent_count;
 920        struct object_array merges;
 921
 922        int i;
 923
 924        /* store a in result in case we fail */
 925        hashcpy(result, a);
 926
 927        /* we can not handle deletion conflicts */
 928        if (is_null_sha1(base))
 929                return 0;
 930        if (is_null_sha1(a))
 931                return 0;
 932        if (is_null_sha1(b))
 933                return 0;
 934
 935        if (add_submodule_odb(path)) {
 936                MERGE_WARNING(path, "not checked out");
 937                return 0;
 938        }
 939
 940        if (!(commit_base = lookup_commit_reference(base)) ||
 941            !(commit_a = lookup_commit_reference(a)) ||
 942            !(commit_b = lookup_commit_reference(b))) {
 943                MERGE_WARNING(path, "commits not present");
 944                return 0;
 945        }
 946
 947        /* check whether both changes are forward */
 948        if (!in_merge_bases(commit_base, commit_a) ||
 949            !in_merge_bases(commit_base, commit_b)) {
 950                MERGE_WARNING(path, "commits don't follow merge-base");
 951                return 0;
 952        }
 953
 954        /* Case #1: a is contained in b or vice versa */
 955        if (in_merge_bases(commit_a, commit_b)) {
 956                hashcpy(result, b);
 957                return 1;
 958        }
 959        if (in_merge_bases(commit_b, commit_a)) {
 960                hashcpy(result, a);
 961                return 1;
 962        }
 963
 964        /*
 965         * Case #2: There are one or more merges that contain a and b in
 966         * the submodule. If there is only one, then present it as a
 967         * suggestion to the user, but leave it marked unmerged so the
 968         * user needs to confirm the resolution.
 969         */
 970
 971        /* Skip the search if makes no sense to the calling context.  */
 972        if (!search)
 973                return 0;
 974
 975        /* find commit which merges them */
 976        parent_count = find_first_merges(&merges, path, commit_a, commit_b);
 977        switch (parent_count) {
 978        case 0:
 979                MERGE_WARNING(path, "merge following commits not found");
 980                break;
 981
 982        case 1:
 983                MERGE_WARNING(path, "not fast-forward");
 984                fprintf(stderr, "Found a possible merge resolution "
 985                                "for the submodule:\n");
 986                print_commit((struct commit *) merges.objects[0].item);
 987                fprintf(stderr,
 988                        "If this is correct simply add it to the index "
 989                        "for example\n"
 990                        "by using:\n\n"
 991                        "  git update-index --cacheinfo 160000 %s \"%s\"\n\n"
 992                        "which will accept this suggestion.\n",
 993                        sha1_to_hex(merges.objects[0].item->sha1), path);
 994                break;
 995
 996        default:
 997                MERGE_WARNING(path, "multiple merges found");
 998                for (i = 0; i < merges.nr; i++)
 999                        print_commit((struct commit *) merges.objects[i].item);
1000        }
1001
1002        free(merges.objects);
1003        return 0;
1004}