Andrew's git / gitweb.git / submodule.c
?
submodule.con commit push: allow already-exists advice to be disabled (b450568)
   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        int len;
 130        struct string_list_item *config;
 131        struct strbuf submodname = STRBUF_INIT;
 132
 133        var += 10;              /* Skip "submodule." */
 134
 135        len = strlen(var);
 136        if ((len > 5) && !strcmp(var + len - 5, ".path")) {
 137                strbuf_add(&submodname, var, len - 5);
 138                config = unsorted_string_list_lookup(&config_name_for_path, value);
 139                if (config)
 140                        free(config->util);
 141                else
 142                        config = string_list_append(&config_name_for_path, xstrdup(value));
 143                config->util = strbuf_detach(&submodname, NULL);
 144                strbuf_release(&submodname);
 145        } else if ((len > 23) && !strcmp(var + len - 23, ".fetchrecursesubmodules")) {
 146                strbuf_add(&submodname, var, len - 23);
 147                config = unsorted_string_list_lookup(&config_fetch_recurse_submodules_for_name, submodname.buf);
 148                if (!config)
 149                        config = string_list_append(&config_fetch_recurse_submodules_for_name,
 150                                                    strbuf_detach(&submodname, NULL));
 151                config->util = (void *)(intptr_t)parse_fetch_recurse_submodules_arg(var, value);
 152                strbuf_release(&submodname);
 153        } else if ((len > 7) && !strcmp(var + len - 7, ".ignore")) {
 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                strbuf_add(&submodname, var, len - 7);
 161                config = unsorted_string_list_lookup(&config_ignore_for_name, submodname.buf);
 162                if (config)
 163                        free(config->util);
 164                else
 165                        config = string_list_append(&config_ignore_for_name,
 166                                                    strbuf_detach(&submodname, NULL));
 167                strbuf_release(&submodname);
 168                config->util = xstrdup(value);
 169                return 0;
 170        }
 171        return 0;
 172}
 173
 174void handle_ignore_submodules_arg(struct diff_options *diffopt,
 175                                  const char *arg)
 176{
 177        DIFF_OPT_CLR(diffopt, IGNORE_SUBMODULES);
 178        DIFF_OPT_CLR(diffopt, IGNORE_UNTRACKED_IN_SUBMODULES);
 179        DIFF_OPT_CLR(diffopt, IGNORE_DIRTY_SUBMODULES);
 180
 181        if (!strcmp(arg, "all"))
 182                DIFF_OPT_SET(diffopt, IGNORE_SUBMODULES);
 183        else if (!strcmp(arg, "untracked"))
 184                DIFF_OPT_SET(diffopt, IGNORE_UNTRACKED_IN_SUBMODULES);
 185        else if (!strcmp(arg, "dirty"))
 186                DIFF_OPT_SET(diffopt, IGNORE_DIRTY_SUBMODULES);
 187        else if (strcmp(arg, "none"))
 188                die("bad --ignore-submodules argument: %s", arg);
 189}
 190
 191static int prepare_submodule_summary(struct rev_info *rev, const char *path,
 192                struct commit *left, struct commit *right,
 193                int *fast_forward, int *fast_backward)
 194{
 195        struct commit_list *merge_bases, *list;
 196
 197        init_revisions(rev, NULL);
 198        setup_revisions(0, NULL, rev, NULL);
 199        rev->left_right = 1;
 200        rev->first_parent_only = 1;
 201        left->object.flags |= SYMMETRIC_LEFT;
 202        add_pending_object(rev, &left->object, path);
 203        add_pending_object(rev, &right->object, path);
 204        merge_bases = get_merge_bases(left, right, 1);
 205        if (merge_bases) {
 206                if (merge_bases->item == left)
 207                        *fast_forward = 1;
 208                else if (merge_bases->item == right)
 209                        *fast_backward = 1;
 210        }
 211        for (list = merge_bases; list; list = list->next) {
 212                list->item->object.flags |= UNINTERESTING;
 213                add_pending_object(rev, &list->item->object,
 214                        sha1_to_hex(list->item->object.sha1));
 215        }
 216        return prepare_revision_walk(rev);
 217}
 218
 219static void print_submodule_summary(struct rev_info *rev, FILE *f,
 220                const char *del, const char *add, const char *reset)
 221{
 222        static const char format[] = "  %m %s";
 223        struct strbuf sb = STRBUF_INIT;
 224        struct commit *commit;
 225
 226        while ((commit = get_revision(rev))) {
 227                struct pretty_print_context ctx = {0};
 228                ctx.date_mode = rev->date_mode;
 229                strbuf_setlen(&sb, 0);
 230                if (commit->object.flags & SYMMETRIC_LEFT) {
 231                        if (del)
 232                                strbuf_addstr(&sb, del);
 233                }
 234                else if (add)
 235                        strbuf_addstr(&sb, add);
 236                format_commit_message(commit, format, &sb, &ctx);
 237                if (reset)
 238                        strbuf_addstr(&sb, reset);
 239                strbuf_addch(&sb, '\n');
 240                fprintf(f, "%s", sb.buf);
 241        }
 242        strbuf_release(&sb);
 243}
 244
 245int parse_fetch_recurse_submodules_arg(const char *opt, const char *arg)
 246{
 247        switch (git_config_maybe_bool(opt, arg)) {
 248        case 1:
 249                return RECURSE_SUBMODULES_ON;
 250        case 0:
 251                return RECURSE_SUBMODULES_OFF;
 252        default:
 253                if (!strcmp(arg, "on-demand"))
 254                        return RECURSE_SUBMODULES_ON_DEMAND;
 255                die("bad %s argument: %s", opt, arg);
 256        }
 257}
 258
 259void show_submodule_summary(FILE *f, const char *path,
 260                unsigned char one[20], unsigned char two[20],
 261                unsigned dirty_submodule,
 262                const char *del, const char *add, const char *reset)
 263{
 264        struct rev_info rev;
 265        struct commit *left = left, *right = right;
 266        const char *message = NULL;
 267        struct strbuf sb = STRBUF_INIT;
 268        int fast_forward = 0, fast_backward = 0;
 269
 270        if (is_null_sha1(two))
 271                message = "(submodule deleted)";
 272        else if (add_submodule_odb(path))
 273                message = "(not checked out)";
 274        else if (is_null_sha1(one))
 275                message = "(new submodule)";
 276        else if (!(left = lookup_commit_reference(one)) ||
 277                 !(right = lookup_commit_reference(two)))
 278                message = "(commits not present)";
 279
 280        if (!message &&
 281            prepare_submodule_summary(&rev, path, left, right,
 282                                        &fast_forward, &fast_backward))
 283                message = "(revision walker failed)";
 284
 285        if (dirty_submodule & DIRTY_SUBMODULE_UNTRACKED)
 286                fprintf(f, "Submodule %s contains untracked content\n", path);
 287        if (dirty_submodule & DIRTY_SUBMODULE_MODIFIED)
 288                fprintf(f, "Submodule %s contains modified content\n", path);
 289
 290        if (!hashcmp(one, two)) {
 291                strbuf_release(&sb);
 292                return;
 293        }
 294
 295        strbuf_addf(&sb, "Submodule %s %s..", path,
 296                        find_unique_abbrev(one, DEFAULT_ABBREV));
 297        if (!fast_backward && !fast_forward)
 298                strbuf_addch(&sb, '.');
 299        strbuf_addf(&sb, "%s", find_unique_abbrev(two, DEFAULT_ABBREV));
 300        if (message)
 301                strbuf_addf(&sb, " %s\n", message);
 302        else
 303                strbuf_addf(&sb, "%s:\n", fast_backward ? " (rewind)" : "");
 304        fwrite(sb.buf, sb.len, 1, f);
 305
 306        if (!message) {
 307                print_submodule_summary(&rev, f, del, add, reset);
 308                clear_commit_marks(left, ~0);
 309                clear_commit_marks(right, ~0);
 310        }
 311
 312        strbuf_release(&sb);
 313}
 314
 315void set_config_fetch_recurse_submodules(int value)
 316{
 317        config_fetch_recurse_submodules = value;
 318}
 319
 320static int has_remote(const char *refname, const unsigned char *sha1, int flags, void *cb_data)
 321{
 322        return 1;
 323}
 324
 325static int submodule_needs_pushing(const char *path, const unsigned char sha1[20])
 326{
 327        if (add_submodule_odb(path) || !lookup_commit_reference(sha1))
 328                return 0;
 329
 330        if (for_each_remote_ref_submodule(path, has_remote, NULL) > 0) {
 331                struct child_process cp;
 332                const char *argv[] = {"rev-list", NULL, "--not", "--remotes", "-n", "1" , NULL};
 333                struct strbuf buf = STRBUF_INIT;
 334                int needs_pushing = 0;
 335
 336                argv[1] = sha1_to_hex(sha1);
 337                memset(&cp, 0, sizeof(cp));
 338                cp.argv = argv;
 339                cp.env = local_repo_env;
 340                cp.git_cmd = 1;
 341                cp.no_stdin = 1;
 342                cp.out = -1;
 343                cp.dir = path;
 344                if (start_command(&cp))
 345                        die("Could not run 'git rev-list %s --not --remotes -n 1' command in submodule %s",
 346                                sha1_to_hex(sha1), path);
 347                if (strbuf_read(&buf, cp.out, 41))
 348                        needs_pushing = 1;
 349                finish_command(&cp);
 350                close(cp.out);
 351                strbuf_release(&buf);
 352                return needs_pushing;
 353        }
 354
 355        return 0;
 356}
 357
 358static void collect_submodules_from_diff(struct diff_queue_struct *q,
 359                                         struct diff_options *options,
 360                                         void *data)
 361{
 362        int i;
 363        struct string_list *needs_pushing = data;
 364
 365        for (i = 0; i < q->nr; i++) {
 366                struct diff_filepair *p = q->queue[i];
 367                if (!S_ISGITLINK(p->two->mode))
 368                        continue;
 369                if (submodule_needs_pushing(p->two->path, p->two->sha1))
 370                        string_list_insert(needs_pushing, p->two->path);
 371        }
 372}
 373
 374static void find_unpushed_submodule_commits(struct commit *commit,
 375                struct string_list *needs_pushing)
 376{
 377        struct rev_info rev;
 378
 379        init_revisions(&rev, NULL);
 380        rev.diffopt.output_format |= DIFF_FORMAT_CALLBACK;
 381        rev.diffopt.format_callback = collect_submodules_from_diff;
 382        rev.diffopt.format_callback_data = needs_pushing;
 383        diff_tree_combined_merge(commit, 1, &rev);
 384}
 385
 386int find_unpushed_submodules(unsigned char new_sha1[20],
 387                const char *remotes_name, struct string_list *needs_pushing)
 388{
 389        struct rev_info rev;
 390        struct commit *commit;
 391        const char *argv[] = {NULL, NULL, "--not", "NULL", NULL};
 392        int argc = ARRAY_SIZE(argv) - 1;
 393        char *sha1_copy;
 394
 395        struct strbuf remotes_arg = STRBUF_INIT;
 396
 397        strbuf_addf(&remotes_arg, "--remotes=%s", remotes_name);
 398        init_revisions(&rev, NULL);
 399        sha1_copy = xstrdup(sha1_to_hex(new_sha1));
 400        argv[1] = sha1_copy;
 401        argv[3] = remotes_arg.buf;
 402        setup_revisions(argc, argv, &rev, NULL);
 403        if (prepare_revision_walk(&rev))
 404                die("revision walk setup failed");
 405
 406        while ((commit = get_revision(&rev)) != NULL)
 407                find_unpushed_submodule_commits(commit, needs_pushing);
 408
 409        reset_revision_walk();
 410        free(sha1_copy);
 411        strbuf_release(&remotes_arg);
 412
 413        return needs_pushing->nr;
 414}
 415
 416static int push_submodule(const char *path)
 417{
 418        if (add_submodule_odb(path))
 419                return 1;
 420
 421        if (for_each_remote_ref_submodule(path, has_remote, NULL) > 0) {
 422                struct child_process cp;
 423                const char *argv[] = {"push", NULL};
 424
 425                memset(&cp, 0, sizeof(cp));
 426                cp.argv = argv;
 427                cp.env = local_repo_env;
 428                cp.git_cmd = 1;
 429                cp.no_stdin = 1;
 430                cp.dir = path;
 431                if (run_command(&cp))
 432                        return 0;
 433                close(cp.out);
 434        }
 435
 436        return 1;
 437}
 438
 439int push_unpushed_submodules(unsigned char new_sha1[20], const char *remotes_name)
 440{
 441        int i, ret = 1;
 442        struct string_list needs_pushing;
 443
 444        memset(&needs_pushing, 0, sizeof(struct string_list));
 445        needs_pushing.strdup_strings = 1;
 446
 447        if (!find_unpushed_submodules(new_sha1, remotes_name, &needs_pushing))
 448                return 1;
 449
 450        for (i = 0; i < needs_pushing.nr; i++) {
 451                const char *path = needs_pushing.items[i].string;
 452                fprintf(stderr, "Pushing submodule '%s'\n", path);
 453                if (!push_submodule(path)) {
 454                        fprintf(stderr, "Unable to push submodule '%s'\n", path);
 455                        ret = 0;
 456                }
 457        }
 458
 459        string_list_clear(&needs_pushing, 0);
 460
 461        return ret;
 462}
 463
 464static int is_submodule_commit_present(const char *path, unsigned char sha1[20])
 465{
 466        int is_present = 0;
 467        if (!add_submodule_odb(path) && lookup_commit_reference(sha1)) {
 468                /* Even if the submodule is checked out and the commit is
 469                 * present, make sure it is reachable from a ref. */
 470                struct child_process cp;
 471                const char *argv[] = {"rev-list", "-n", "1", NULL, "--not", "--all", NULL};
 472                struct strbuf buf = STRBUF_INIT;
 473
 474                argv[3] = sha1_to_hex(sha1);
 475                memset(&cp, 0, sizeof(cp));
 476                cp.argv = argv;
 477                cp.env = local_repo_env;
 478                cp.git_cmd = 1;
 479                cp.no_stdin = 1;
 480                cp.out = -1;
 481                cp.dir = path;
 482                if (!run_command(&cp) && !strbuf_read(&buf, cp.out, 1024))
 483                        is_present = 1;
 484
 485                close(cp.out);
 486                strbuf_release(&buf);
 487        }
 488        return is_present;
 489}
 490
 491static void submodule_collect_changed_cb(struct diff_queue_struct *q,
 492                                         struct diff_options *options,
 493                                         void *data)
 494{
 495        int i;
 496        for (i = 0; i < q->nr; i++) {
 497                struct diff_filepair *p = q->queue[i];
 498                if (!S_ISGITLINK(p->two->mode))
 499                        continue;
 500
 501                if (S_ISGITLINK(p->one->mode)) {
 502                        /* NEEDSWORK: We should honor the name configured in
 503                         * the .gitmodules file of the commit we are examining
 504                         * here to be able to correctly follow submodules
 505                         * being moved around. */
 506                        struct string_list_item *path;
 507                        path = unsorted_string_list_lookup(&changed_submodule_paths, p->two->path);
 508                        if (!path && !is_submodule_commit_present(p->two->path, p->two->sha1))
 509                                string_list_append(&changed_submodule_paths, xstrdup(p->two->path));
 510                } else {
 511                        /* Submodule is new or was moved here */
 512                        /* NEEDSWORK: When the .git directories of submodules
 513                         * live inside the superprojects .git directory some
 514                         * day we should fetch new submodules directly into
 515                         * that location too when config or options request
 516                         * that so they can be checked out from there. */
 517                        continue;
 518                }
 519        }
 520}
 521
 522static int add_sha1_to_array(const char *ref, const unsigned char *sha1,
 523                             int flags, void *data)
 524{
 525        sha1_array_append(data, sha1);
 526        return 0;
 527}
 528
 529void check_for_new_submodule_commits(unsigned char new_sha1[20])
 530{
 531        if (!initialized_fetch_ref_tips) {
 532                for_each_ref(add_sha1_to_array, &ref_tips_before_fetch);
 533                initialized_fetch_ref_tips = 1;
 534        }
 535
 536        sha1_array_append(&ref_tips_after_fetch, new_sha1);
 537}
 538
 539static void add_sha1_to_argv(const unsigned char sha1[20], void *data)
 540{
 541        argv_array_push(data, sha1_to_hex(sha1));
 542}
 543
 544static void calculate_changed_submodule_paths(void)
 545{
 546        struct rev_info rev;
 547        struct commit *commit;
 548        struct argv_array argv = ARGV_ARRAY_INIT;
 549
 550        /* No need to check if there are no submodules configured */
 551        if (!config_name_for_path.nr)
 552                return;
 553
 554        init_revisions(&rev, NULL);
 555        argv_array_push(&argv, "--"); /* argv[0] program name */
 556        sha1_array_for_each_unique(&ref_tips_after_fetch,
 557                                   add_sha1_to_argv, &argv);
 558        argv_array_push(&argv, "--not");
 559        sha1_array_for_each_unique(&ref_tips_before_fetch,
 560                                   add_sha1_to_argv, &argv);
 561        setup_revisions(argv.argc, argv.argv, &rev, NULL);
 562        if (prepare_revision_walk(&rev))
 563                die("revision walk setup failed");
 564
 565        /*
 566         * Collect all submodules (whether checked out or not) for which new
 567         * commits have been recorded upstream in "changed_submodule_paths".
 568         */
 569        while ((commit = get_revision(&rev))) {
 570                struct commit_list *parent = commit->parents;
 571                while (parent) {
 572                        struct diff_options diff_opts;
 573                        diff_setup(&diff_opts);
 574                        DIFF_OPT_SET(&diff_opts, RECURSIVE);
 575                        diff_opts.output_format |= DIFF_FORMAT_CALLBACK;
 576                        diff_opts.format_callback = submodule_collect_changed_cb;
 577                        diff_setup_done(&diff_opts);
 578                        diff_tree_sha1(parent->item->object.sha1, commit->object.sha1, "", &diff_opts);
 579                        diffcore_std(&diff_opts);
 580                        diff_flush(&diff_opts);
 581                        parent = parent->next;
 582                }
 583        }
 584
 585        argv_array_clear(&argv);
 586        sha1_array_clear(&ref_tips_before_fetch);
 587        sha1_array_clear(&ref_tips_after_fetch);
 588        initialized_fetch_ref_tips = 0;
 589}
 590
 591int fetch_populated_submodules(const struct argv_array *options,
 592                               const char *prefix, int command_line_option,
 593                               int quiet)
 594{
 595        int i, result = 0;
 596        struct child_process cp;
 597        struct argv_array argv = ARGV_ARRAY_INIT;
 598        struct string_list_item *name_for_path;
 599        const char *work_tree = get_git_work_tree();
 600        if (!work_tree)
 601                goto out;
 602
 603        if (!the_index.initialized)
 604                if (read_cache() < 0)
 605                        die("index file corrupt");
 606
 607        argv_array_push(&argv, "fetch");
 608        for (i = 0; i < options->argc; i++)
 609                argv_array_push(&argv, options->argv[i]);
 610        argv_array_push(&argv, "--recurse-submodules-default");
 611        /* default value, "--submodule-prefix" and its value are added later */
 612
 613        memset(&cp, 0, sizeof(cp));
 614        cp.env = local_repo_env;
 615        cp.git_cmd = 1;
 616        cp.no_stdin = 1;
 617
 618        calculate_changed_submodule_paths();
 619
 620        for (i = 0; i < active_nr; i++) {
 621                struct strbuf submodule_path = STRBUF_INIT;
 622                struct strbuf submodule_git_dir = STRBUF_INIT;
 623                struct strbuf submodule_prefix = STRBUF_INIT;
 624                struct cache_entry *ce = active_cache[i];
 625                const char *git_dir, *name, *default_argv;
 626
 627                if (!S_ISGITLINK(ce->ce_mode))
 628                        continue;
 629
 630                name = ce->name;
 631                name_for_path = unsorted_string_list_lookup(&config_name_for_path, ce->name);
 632                if (name_for_path)
 633                        name = name_for_path->util;
 634
 635                default_argv = "yes";
 636                if (command_line_option == RECURSE_SUBMODULES_DEFAULT) {
 637                        struct string_list_item *fetch_recurse_submodules_option;
 638                        fetch_recurse_submodules_option = unsorted_string_list_lookup(&config_fetch_recurse_submodules_for_name, name);
 639                        if (fetch_recurse_submodules_option) {
 640                                if ((intptr_t)fetch_recurse_submodules_option->util == RECURSE_SUBMODULES_OFF)
 641                                        continue;
 642                                if ((intptr_t)fetch_recurse_submodules_option->util == RECURSE_SUBMODULES_ON_DEMAND) {
 643                                        if (!unsorted_string_list_lookup(&changed_submodule_paths, ce->name))
 644                                                continue;
 645                                        default_argv = "on-demand";
 646                                }
 647                        } else {
 648                                if ((config_fetch_recurse_submodules == RECURSE_SUBMODULES_OFF) ||
 649                                    gitmodules_is_unmerged)
 650                                        continue;
 651                                if (config_fetch_recurse_submodules == RECURSE_SUBMODULES_ON_DEMAND) {
 652                                        if (!unsorted_string_list_lookup(&changed_submodule_paths, ce->name))
 653                                                continue;
 654                                        default_argv = "on-demand";
 655                                }
 656                        }
 657                } else if (command_line_option == RECURSE_SUBMODULES_ON_DEMAND) {
 658                        if (!unsorted_string_list_lookup(&changed_submodule_paths, ce->name))
 659                                continue;
 660                        default_argv = "on-demand";
 661                }
 662
 663                strbuf_addf(&submodule_path, "%s/%s", work_tree, ce->name);
 664                strbuf_addf(&submodule_git_dir, "%s/.git", submodule_path.buf);
 665                strbuf_addf(&submodule_prefix, "%s%s/", prefix, ce->name);
 666                git_dir = read_gitfile(submodule_git_dir.buf);
 667                if (!git_dir)
 668                        git_dir = submodule_git_dir.buf;
 669                if (is_directory(git_dir)) {
 670                        if (!quiet)
 671                                printf("Fetching submodule %s%s\n", prefix, ce->name);
 672                        cp.dir = submodule_path.buf;
 673                        argv_array_push(&argv, default_argv);
 674                        argv_array_push(&argv, "--submodule-prefix");
 675                        argv_array_push(&argv, submodule_prefix.buf);
 676                        cp.argv = argv.argv;
 677                        if (run_command(&cp))
 678                                result = 1;
 679                        argv_array_pop(&argv);
 680                        argv_array_pop(&argv);
 681                        argv_array_pop(&argv);
 682                }
 683                strbuf_release(&submodule_path);
 684                strbuf_release(&submodule_git_dir);
 685                strbuf_release(&submodule_prefix);
 686        }
 687        argv_array_clear(&argv);
 688out:
 689        string_list_clear(&changed_submodule_paths, 1);
 690        return result;
 691}
 692
 693unsigned is_submodule_modified(const char *path, int ignore_untracked)
 694{
 695        ssize_t len;
 696        struct child_process cp;
 697        const char *argv[] = {
 698                "status",
 699                "--porcelain",
 700                NULL,
 701                NULL,
 702        };
 703        struct strbuf buf = STRBUF_INIT;
 704        unsigned dirty_submodule = 0;
 705        const char *line, *next_line;
 706        const char *git_dir;
 707
 708        strbuf_addf(&buf, "%s/.git", path);
 709        git_dir = read_gitfile(buf.buf);
 710        if (!git_dir)
 711                git_dir = buf.buf;
 712        if (!is_directory(git_dir)) {
 713                strbuf_release(&buf);
 714                /* The submodule is not checked out, so it is not modified */
 715                return 0;
 716
 717        }
 718        strbuf_reset(&buf);
 719
 720        if (ignore_untracked)
 721                argv[2] = "-uno";
 722
 723        memset(&cp, 0, sizeof(cp));
 724        cp.argv = argv;
 725        cp.env = local_repo_env;
 726        cp.git_cmd = 1;
 727        cp.no_stdin = 1;
 728        cp.out = -1;
 729        cp.dir = path;
 730        if (start_command(&cp))
 731                die("Could not run 'git status --porcelain' in submodule %s", path);
 732
 733        len = strbuf_read(&buf, cp.out, 1024);
 734        line = buf.buf;
 735        while (len > 2) {
 736                if ((line[0] == '?') && (line[1] == '?')) {
 737                        dirty_submodule |= DIRTY_SUBMODULE_UNTRACKED;
 738                        if (dirty_submodule & DIRTY_SUBMODULE_MODIFIED)
 739                                break;
 740                } else {
 741                        dirty_submodule |= DIRTY_SUBMODULE_MODIFIED;
 742                        if (ignore_untracked ||
 743                            (dirty_submodule & DIRTY_SUBMODULE_UNTRACKED))
 744                                break;
 745                }
 746                next_line = strchr(line, '\n');
 747                if (!next_line)
 748                        break;
 749                next_line++;
 750                len -= (next_line - line);
 751                line = next_line;
 752        }
 753        close(cp.out);
 754
 755        if (finish_command(&cp))
 756                die("'git status --porcelain' failed in submodule %s", path);
 757
 758        strbuf_release(&buf);
 759        return dirty_submodule;
 760}
 761
 762int submodule_uses_gitfile(const char *path)
 763{
 764        struct child_process cp;
 765        const char *argv[] = {
 766                "submodule",
 767                "foreach",
 768                "--quiet",
 769                "--recursive",
 770                "test -f .git",
 771                NULL,
 772        };
 773        struct strbuf buf = STRBUF_INIT;
 774        const char *git_dir;
 775
 776        strbuf_addf(&buf, "%s/.git", path);
 777        git_dir = read_gitfile(buf.buf);
 778        if (!git_dir) {
 779                strbuf_release(&buf);
 780                return 0;
 781        }
 782        strbuf_release(&buf);
 783
 784        /* Now test that all nested submodules use a gitfile too */
 785        memset(&cp, 0, sizeof(cp));
 786        cp.argv = argv;
 787        cp.env = local_repo_env;
 788        cp.git_cmd = 1;
 789        cp.no_stdin = 1;
 790        cp.no_stderr = 1;
 791        cp.no_stdout = 1;
 792        cp.dir = path;
 793        if (run_command(&cp))
 794                return 0;
 795
 796        return 1;
 797}
 798
 799int ok_to_remove_submodule(const char *path)
 800{
 801        struct stat st;
 802        ssize_t len;
 803        struct child_process cp;
 804        const char *argv[] = {
 805                "status",
 806                "--porcelain",
 807                "-u",
 808                "--ignore-submodules=none",
 809                NULL,
 810        };
 811        struct strbuf buf = STRBUF_INIT;
 812        int ok_to_remove = 1;
 813
 814        if ((lstat(path, &st) < 0) || is_empty_dir(path))
 815                return 1;
 816
 817        if (!submodule_uses_gitfile(path))
 818                return 0;
 819
 820        memset(&cp, 0, sizeof(cp));
 821        cp.argv = argv;
 822        cp.env = local_repo_env;
 823        cp.git_cmd = 1;
 824        cp.no_stdin = 1;
 825        cp.out = -1;
 826        cp.dir = path;
 827        if (start_command(&cp))
 828                die("Could not run 'git status --porcelain -uall --ignore-submodules=none' in submodule %s", path);
 829
 830        len = strbuf_read(&buf, cp.out, 1024);
 831        if (len > 2)
 832                ok_to_remove = 0;
 833        close(cp.out);
 834
 835        if (finish_command(&cp))
 836                die("'git status --porcelain -uall --ignore-submodules=none' failed in submodule %s", path);
 837
 838        strbuf_release(&buf);
 839        return ok_to_remove;
 840}
 841
 842static int find_first_merges(struct object_array *result, const char *path,
 843                struct commit *a, struct commit *b)
 844{
 845        int i, j;
 846        struct object_array merges;
 847        struct commit *commit;
 848        int contains_another;
 849
 850        char merged_revision[42];
 851        const char *rev_args[] = { "rev-list", "--merges", "--ancestry-path",
 852                                   "--all", merged_revision, NULL };
 853        struct rev_info revs;
 854        struct setup_revision_opt rev_opts;
 855
 856        memset(&merges, 0, sizeof(merges));
 857        memset(result, 0, sizeof(struct object_array));
 858        memset(&rev_opts, 0, sizeof(rev_opts));
 859
 860        /* get all revisions that merge commit a */
 861        snprintf(merged_revision, sizeof(merged_revision), "^%s",
 862                        sha1_to_hex(a->object.sha1));
 863        init_revisions(&revs, NULL);
 864        rev_opts.submodule = path;
 865        setup_revisions(sizeof(rev_args)/sizeof(char *)-1, rev_args, &revs, &rev_opts);
 866
 867        /* save all revisions from the above list that contain b */
 868        if (prepare_revision_walk(&revs))
 869                die("revision walk setup failed");
 870        while ((commit = get_revision(&revs)) != NULL) {
 871                struct object *o = &(commit->object);
 872                if (in_merge_bases(b, commit))
 873                        add_object_array(o, NULL, &merges);
 874        }
 875        reset_revision_walk();
 876
 877        /* Now we've got all merges that contain a and b. Prune all
 878         * merges that contain another found merge and save them in
 879         * result.
 880         */
 881        for (i = 0; i < merges.nr; i++) {
 882                struct commit *m1 = (struct commit *) merges.objects[i].item;
 883
 884                contains_another = 0;
 885                for (j = 0; j < merges.nr; j++) {
 886                        struct commit *m2 = (struct commit *) merges.objects[j].item;
 887                        if (i != j && in_merge_bases(m2, m1)) {
 888                                contains_another = 1;
 889                                break;
 890                        }
 891                }
 892
 893                if (!contains_another)
 894                        add_object_array(merges.objects[i].item,
 895                                         merges.objects[i].name, result);
 896        }
 897
 898        free(merges.objects);
 899        return result->nr;
 900}
 901
 902static void print_commit(struct commit *commit)
 903{
 904        struct strbuf sb = STRBUF_INIT;
 905        struct pretty_print_context ctx = {0};
 906        ctx.date_mode = DATE_NORMAL;
 907        format_commit_message(commit, " %h: %m %s", &sb, &ctx);
 908        fprintf(stderr, "%s\n", sb.buf);
 909        strbuf_release(&sb);
 910}
 911
 912#define MERGE_WARNING(path, msg) \
 913        warning("Failed to merge submodule %s (%s)", path, msg);
 914
 915int merge_submodule(unsigned char result[20], const char *path,
 916                    const unsigned char base[20], const unsigned char a[20],
 917                    const unsigned char b[20], int search)
 918{
 919        struct commit *commit_base, *commit_a, *commit_b;
 920        int parent_count;
 921        struct object_array merges;
 922
 923        int i;
 924
 925        /* store a in result in case we fail */
 926        hashcpy(result, a);
 927
 928        /* we can not handle deletion conflicts */
 929        if (is_null_sha1(base))
 930                return 0;
 931        if (is_null_sha1(a))
 932                return 0;
 933        if (is_null_sha1(b))
 934                return 0;
 935
 936        if (add_submodule_odb(path)) {
 937                MERGE_WARNING(path, "not checked out");
 938                return 0;
 939        }
 940
 941        if (!(commit_base = lookup_commit_reference(base)) ||
 942            !(commit_a = lookup_commit_reference(a)) ||
 943            !(commit_b = lookup_commit_reference(b))) {
 944                MERGE_WARNING(path, "commits not present");
 945                return 0;
 946        }
 947
 948        /* check whether both changes are forward */
 949        if (!in_merge_bases(commit_base, commit_a) ||
 950            !in_merge_bases(commit_base, commit_b)) {
 951                MERGE_WARNING(path, "commits don't follow merge-base");
 952                return 0;
 953        }
 954
 955        /* Case #1: a is contained in b or vice versa */
 956        if (in_merge_bases(commit_a, commit_b)) {
 957                hashcpy(result, b);
 958                return 1;
 959        }
 960        if (in_merge_bases(commit_b, commit_a)) {
 961                hashcpy(result, a);
 962                return 1;
 963        }
 964
 965        /*
 966         * Case #2: There are one or more merges that contain a and b in
 967         * the submodule. If there is only one, then present it as a
 968         * suggestion to the user, but leave it marked unmerged so the
 969         * user needs to confirm the resolution.
 970         */
 971
 972        /* Skip the search if makes no sense to the calling context.  */
 973        if (!search)
 974                return 0;
 975
 976        /* find commit which merges them */
 977        parent_count = find_first_merges(&merges, path, commit_a, commit_b);
 978        switch (parent_count) {
 979        case 0:
 980                MERGE_WARNING(path, "merge following commits not found");
 981                break;
 982
 983        case 1:
 984                MERGE_WARNING(path, "not fast-forward");
 985                fprintf(stderr, "Found a possible merge resolution "
 986                                "for the submodule:\n");
 987                print_commit((struct commit *) merges.objects[0].item);
 988                fprintf(stderr,
 989                        "If this is correct simply add it to the index "
 990                        "for example\n"
 991                        "by using:\n\n"
 992                        "  git update-index --cacheinfo 160000 %s \"%s\"\n\n"
 993                        "which will accept this suggestion.\n",
 994                        sha1_to_hex(merges.objects[0].item->sha1), path);
 995                break;
 996
 997        default:
 998                MERGE_WARNING(path, "multiple merges found");
 999                for (i = 0; i < merges.nr; i++)
1000                        print_commit((struct commit *) merges.objects[i].item);
1001        }
1002
1003        free(merges.objects);
1004        return 0;
1005}