Andrew's git / gitweb.git / submodule.c
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submodule.con commit test: modernize style of t4006 (ec57a82)
   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        prepare_alt_odb();
  67done:
  68        strbuf_release(&objects_directory);
  69        return ret;
  70}
  71
  72void set_diffopt_flags_from_submodule_config(struct diff_options *diffopt,
  73                                             const char *path)
  74{
  75        struct string_list_item *path_option, *ignore_option;
  76        path_option = unsorted_string_list_lookup(&config_name_for_path, path);
  77        if (path_option) {
  78                ignore_option = unsorted_string_list_lookup(&config_ignore_for_name, path_option->util);
  79                if (ignore_option)
  80                        handle_ignore_submodules_arg(diffopt, ignore_option->util);
  81                else if (gitmodules_is_unmerged)
  82                        DIFF_OPT_SET(diffopt, IGNORE_SUBMODULES);
  83        }
  84}
  85
  86int submodule_config(const char *var, const char *value, void *cb)
  87{
  88        if (!prefixcmp(var, "submodule."))
  89                return parse_submodule_config_option(var, value);
  90        else if (!strcmp(var, "fetch.recursesubmodules")) {
  91                config_fetch_recurse_submodules = parse_fetch_recurse_submodules_arg(var, value);
  92                return 0;
  93        }
  94        return 0;
  95}
  96
  97void gitmodules_config(void)
  98{
  99        const char *work_tree = get_git_work_tree();
 100        if (work_tree) {
 101                struct strbuf gitmodules_path = STRBUF_INIT;
 102                int pos;
 103                strbuf_addstr(&gitmodules_path, work_tree);
 104                strbuf_addstr(&gitmodules_path, "/.gitmodules");
 105                if (read_cache() < 0)
 106                        die("index file corrupt");
 107                pos = cache_name_pos(".gitmodules", 11);
 108                if (pos < 0) { /* .gitmodules not found or isn't merged */
 109                        pos = -1 - pos;
 110                        if (active_nr > pos) {  /* there is a .gitmodules */
 111                                const struct cache_entry *ce = active_cache[pos];
 112                                if (ce_namelen(ce) == 11 &&
 113                                    !memcmp(ce->name, ".gitmodules", 11))
 114                                        gitmodules_is_unmerged = 1;
 115                        }
 116                }
 117
 118                if (!gitmodules_is_unmerged)
 119                        git_config_from_file(submodule_config, gitmodules_path.buf, NULL);
 120                strbuf_release(&gitmodules_path);
 121        }
 122}
 123
 124int parse_submodule_config_option(const char *var, const char *value)
 125{
 126        int len;
 127        struct string_list_item *config;
 128        struct strbuf submodname = STRBUF_INIT;
 129
 130        var += 10;              /* Skip "submodule." */
 131
 132        len = strlen(var);
 133        if ((len > 5) && !strcmp(var + len - 5, ".path")) {
 134                strbuf_add(&submodname, var, len - 5);
 135                config = unsorted_string_list_lookup(&config_name_for_path, value);
 136                if (config)
 137                        free(config->util);
 138                else
 139                        config = string_list_append(&config_name_for_path, xstrdup(value));
 140                config->util = strbuf_detach(&submodname, NULL);
 141                strbuf_release(&submodname);
 142        } else if ((len > 23) && !strcmp(var + len - 23, ".fetchrecursesubmodules")) {
 143                strbuf_add(&submodname, var, len - 23);
 144                config = unsorted_string_list_lookup(&config_fetch_recurse_submodules_for_name, submodname.buf);
 145                if (!config)
 146                        config = string_list_append(&config_fetch_recurse_submodules_for_name,
 147                                                    strbuf_detach(&submodname, NULL));
 148                config->util = (void *)(intptr_t)parse_fetch_recurse_submodules_arg(var, value);
 149                strbuf_release(&submodname);
 150        } else if ((len > 7) && !strcmp(var + len - 7, ".ignore")) {
 151                if (strcmp(value, "untracked") && strcmp(value, "dirty") &&
 152                    strcmp(value, "all") && strcmp(value, "none")) {
 153                        warning("Invalid parameter \"%s\" for config option \"submodule.%s.ignore\"", value, var);
 154                        return 0;
 155                }
 156
 157                strbuf_add(&submodname, var, len - 7);
 158                config = unsorted_string_list_lookup(&config_ignore_for_name, submodname.buf);
 159                if (config)
 160                        free(config->util);
 161                else
 162                        config = string_list_append(&config_ignore_for_name,
 163                                                    strbuf_detach(&submodname, NULL));
 164                strbuf_release(&submodname);
 165                config->util = xstrdup(value);
 166                return 0;
 167        }
 168        return 0;
 169}
 170
 171void handle_ignore_submodules_arg(struct diff_options *diffopt,
 172                                  const char *arg)
 173{
 174        DIFF_OPT_CLR(diffopt, IGNORE_SUBMODULES);
 175        DIFF_OPT_CLR(diffopt, IGNORE_UNTRACKED_IN_SUBMODULES);
 176        DIFF_OPT_CLR(diffopt, IGNORE_DIRTY_SUBMODULES);
 177
 178        if (!strcmp(arg, "all"))
 179                DIFF_OPT_SET(diffopt, IGNORE_SUBMODULES);
 180        else if (!strcmp(arg, "untracked"))
 181                DIFF_OPT_SET(diffopt, IGNORE_UNTRACKED_IN_SUBMODULES);
 182        else if (!strcmp(arg, "dirty"))
 183                DIFF_OPT_SET(diffopt, IGNORE_DIRTY_SUBMODULES);
 184        else if (strcmp(arg, "none"))
 185                die("bad --ignore-submodules argument: %s", arg);
 186}
 187
 188static int prepare_submodule_summary(struct rev_info *rev, const char *path,
 189                struct commit *left, struct commit *right,
 190                int *fast_forward, int *fast_backward)
 191{
 192        struct commit_list *merge_bases, *list;
 193
 194        init_revisions(rev, NULL);
 195        setup_revisions(0, NULL, rev, NULL);
 196        rev->left_right = 1;
 197        rev->first_parent_only = 1;
 198        left->object.flags |= SYMMETRIC_LEFT;
 199        add_pending_object(rev, &left->object, path);
 200        add_pending_object(rev, &right->object, path);
 201        merge_bases = get_merge_bases(left, right, 1);
 202        if (merge_bases) {
 203                if (merge_bases->item == left)
 204                        *fast_forward = 1;
 205                else if (merge_bases->item == right)
 206                        *fast_backward = 1;
 207        }
 208        for (list = merge_bases; list; list = list->next) {
 209                list->item->object.flags |= UNINTERESTING;
 210                add_pending_object(rev, &list->item->object,
 211                        sha1_to_hex(list->item->object.sha1));
 212        }
 213        return prepare_revision_walk(rev);
 214}
 215
 216static void print_submodule_summary(struct rev_info *rev, FILE *f,
 217                const char *del, const char *add, const char *reset)
 218{
 219        static const char format[] = "  %m %s";
 220        struct strbuf sb = STRBUF_INIT;
 221        struct commit *commit;
 222
 223        while ((commit = get_revision(rev))) {
 224                struct pretty_print_context ctx = {0};
 225                ctx.date_mode = rev->date_mode;
 226                strbuf_setlen(&sb, 0);
 227                if (commit->object.flags & SYMMETRIC_LEFT) {
 228                        if (del)
 229                                strbuf_addstr(&sb, del);
 230                }
 231                else if (add)
 232                        strbuf_addstr(&sb, add);
 233                format_commit_message(commit, format, &sb, &ctx);
 234                if (reset)
 235                        strbuf_addstr(&sb, reset);
 236                strbuf_addch(&sb, '\n');
 237                fprintf(f, "%s", sb.buf);
 238        }
 239        strbuf_release(&sb);
 240}
 241
 242int parse_fetch_recurse_submodules_arg(const char *opt, const char *arg)
 243{
 244        switch (git_config_maybe_bool(opt, arg)) {
 245        case 1:
 246                return RECURSE_SUBMODULES_ON;
 247        case 0:
 248                return RECURSE_SUBMODULES_OFF;
 249        default:
 250                if (!strcmp(arg, "on-demand"))
 251                        return RECURSE_SUBMODULES_ON_DEMAND;
 252                die("bad %s argument: %s", opt, arg);
 253        }
 254}
 255
 256void show_submodule_summary(FILE *f, const char *path,
 257                unsigned char one[20], unsigned char two[20],
 258                unsigned dirty_submodule,
 259                const char *del, const char *add, const char *reset)
 260{
 261        struct rev_info rev;
 262        struct commit *left = left, *right = right;
 263        const char *message = NULL;
 264        struct strbuf sb = STRBUF_INIT;
 265        int fast_forward = 0, fast_backward = 0;
 266
 267        if (is_null_sha1(two))
 268                message = "(submodule deleted)";
 269        else if (add_submodule_odb(path))
 270                message = "(not checked out)";
 271        else if (is_null_sha1(one))
 272                message = "(new submodule)";
 273        else if (!(left = lookup_commit_reference(one)) ||
 274                 !(right = lookup_commit_reference(two)))
 275                message = "(commits not present)";
 276
 277        if (!message &&
 278            prepare_submodule_summary(&rev, path, left, right,
 279                                        &fast_forward, &fast_backward))
 280                message = "(revision walker failed)";
 281
 282        if (dirty_submodule & DIRTY_SUBMODULE_UNTRACKED)
 283                fprintf(f, "Submodule %s contains untracked content\n", path);
 284        if (dirty_submodule & DIRTY_SUBMODULE_MODIFIED)
 285                fprintf(f, "Submodule %s contains modified content\n", path);
 286
 287        if (!hashcmp(one, two)) {
 288                strbuf_release(&sb);
 289                return;
 290        }
 291
 292        strbuf_addf(&sb, "Submodule %s %s..", path,
 293                        find_unique_abbrev(one, DEFAULT_ABBREV));
 294        if (!fast_backward && !fast_forward)
 295                strbuf_addch(&sb, '.');
 296        strbuf_addf(&sb, "%s", find_unique_abbrev(two, DEFAULT_ABBREV));
 297        if (message)
 298                strbuf_addf(&sb, " %s\n", message);
 299        else
 300                strbuf_addf(&sb, "%s:\n", fast_backward ? " (rewind)" : "");
 301        fwrite(sb.buf, sb.len, 1, f);
 302
 303        if (!message) {
 304                print_submodule_summary(&rev, f, del, add, reset);
 305                clear_commit_marks(left, ~0);
 306                clear_commit_marks(right, ~0);
 307        }
 308
 309        strbuf_release(&sb);
 310}
 311
 312void set_config_fetch_recurse_submodules(int value)
 313{
 314        config_fetch_recurse_submodules = value;
 315}
 316
 317static int has_remote(const char *refname, const unsigned char *sha1, int flags, void *cb_data)
 318{
 319        return 1;
 320}
 321
 322static int submodule_needs_pushing(const char *path, const unsigned char sha1[20])
 323{
 324        if (add_submodule_odb(path) || !lookup_commit_reference(sha1))
 325                return 0;
 326
 327        if (for_each_remote_ref_submodule(path, has_remote, NULL) > 0) {
 328                struct child_process cp;
 329                const char *argv[] = {"rev-list", NULL, "--not", "--remotes", "-n", "1" , NULL};
 330                struct strbuf buf = STRBUF_INIT;
 331                int needs_pushing = 0;
 332
 333                argv[1] = sha1_to_hex(sha1);
 334                memset(&cp, 0, sizeof(cp));
 335                cp.argv = argv;
 336                cp.env = local_repo_env;
 337                cp.git_cmd = 1;
 338                cp.no_stdin = 1;
 339                cp.out = -1;
 340                cp.dir = path;
 341                if (start_command(&cp))
 342                        die("Could not run 'git rev-list %s --not --remotes -n 1' command in submodule %s",
 343                                sha1_to_hex(sha1), path);
 344                if (strbuf_read(&buf, cp.out, 41))
 345                        needs_pushing = 1;
 346                finish_command(&cp);
 347                close(cp.out);
 348                strbuf_release(&buf);
 349                return needs_pushing;
 350        }
 351
 352        return 0;
 353}
 354
 355static void collect_submodules_from_diff(struct diff_queue_struct *q,
 356                                         struct diff_options *options,
 357                                         void *data)
 358{
 359        int i;
 360        struct string_list *needs_pushing = data;
 361
 362        for (i = 0; i < q->nr; i++) {
 363                struct diff_filepair *p = q->queue[i];
 364                if (!S_ISGITLINK(p->two->mode))
 365                        continue;
 366                if (submodule_needs_pushing(p->two->path, p->two->sha1))
 367                        string_list_insert(needs_pushing, p->two->path);
 368        }
 369}
 370
 371static void find_unpushed_submodule_commits(struct commit *commit,
 372                struct string_list *needs_pushing)
 373{
 374        struct rev_info rev;
 375
 376        init_revisions(&rev, NULL);
 377        rev.diffopt.output_format |= DIFF_FORMAT_CALLBACK;
 378        rev.diffopt.format_callback = collect_submodules_from_diff;
 379        rev.diffopt.format_callback_data = needs_pushing;
 380        diff_tree_combined_merge(commit, 1, &rev);
 381}
 382
 383int find_unpushed_submodules(unsigned char new_sha1[20],
 384                const char *remotes_name, struct string_list *needs_pushing)
 385{
 386        struct rev_info rev;
 387        struct commit *commit;
 388        const char *argv[] = {NULL, NULL, "--not", "NULL", NULL};
 389        int argc = ARRAY_SIZE(argv) - 1;
 390        char *sha1_copy;
 391
 392        struct strbuf remotes_arg = STRBUF_INIT;
 393
 394        strbuf_addf(&remotes_arg, "--remotes=%s", remotes_name);
 395        init_revisions(&rev, NULL);
 396        sha1_copy = xstrdup(sha1_to_hex(new_sha1));
 397        argv[1] = sha1_copy;
 398        argv[3] = remotes_arg.buf;
 399        setup_revisions(argc, argv, &rev, NULL);
 400        if (prepare_revision_walk(&rev))
 401                die("revision walk setup failed");
 402
 403        while ((commit = get_revision(&rev)) != NULL)
 404                find_unpushed_submodule_commits(commit, needs_pushing);
 405
 406        reset_revision_walk();
 407        free(sha1_copy);
 408        strbuf_release(&remotes_arg);
 409
 410        return needs_pushing->nr;
 411}
 412
 413static int push_submodule(const char *path)
 414{
 415        if (add_submodule_odb(path))
 416                return 1;
 417
 418        if (for_each_remote_ref_submodule(path, has_remote, NULL) > 0) {
 419                struct child_process cp;
 420                const char *argv[] = {"push", NULL};
 421
 422                memset(&cp, 0, sizeof(cp));
 423                cp.argv = argv;
 424                cp.env = local_repo_env;
 425                cp.git_cmd = 1;
 426                cp.no_stdin = 1;
 427                cp.dir = path;
 428                if (run_command(&cp))
 429                        return 0;
 430                close(cp.out);
 431        }
 432
 433        return 1;
 434}
 435
 436int push_unpushed_submodules(unsigned char new_sha1[20], const char *remotes_name)
 437{
 438        int i, ret = 1;
 439        struct string_list needs_pushing;
 440
 441        memset(&needs_pushing, 0, sizeof(struct string_list));
 442        needs_pushing.strdup_strings = 1;
 443
 444        if (!find_unpushed_submodules(new_sha1, remotes_name, &needs_pushing))
 445                return 1;
 446
 447        for (i = 0; i < needs_pushing.nr; i++) {
 448                const char *path = needs_pushing.items[i].string;
 449                fprintf(stderr, "Pushing submodule '%s'\n", path);
 450                if (!push_submodule(path)) {
 451                        fprintf(stderr, "Unable to push submodule '%s'\n", path);
 452                        ret = 0;
 453                }
 454        }
 455
 456        string_list_clear(&needs_pushing, 0);
 457
 458        return ret;
 459}
 460
 461static int is_submodule_commit_present(const char *path, unsigned char sha1[20])
 462{
 463        int is_present = 0;
 464        if (!add_submodule_odb(path) && lookup_commit_reference(sha1)) {
 465                /* Even if the submodule is checked out and the commit is
 466                 * present, make sure it is reachable from a ref. */
 467                struct child_process cp;
 468                const char *argv[] = {"rev-list", "-n", "1", NULL, "--not", "--all", NULL};
 469                struct strbuf buf = STRBUF_INIT;
 470
 471                argv[3] = sha1_to_hex(sha1);
 472                memset(&cp, 0, sizeof(cp));
 473                cp.argv = argv;
 474                cp.env = local_repo_env;
 475                cp.git_cmd = 1;
 476                cp.no_stdin = 1;
 477                cp.out = -1;
 478                cp.dir = path;
 479                if (!run_command(&cp) && !strbuf_read(&buf, cp.out, 1024))
 480                        is_present = 1;
 481
 482                close(cp.out);
 483                strbuf_release(&buf);
 484        }
 485        return is_present;
 486}
 487
 488static void submodule_collect_changed_cb(struct diff_queue_struct *q,
 489                                         struct diff_options *options,
 490                                         void *data)
 491{
 492        int i;
 493        for (i = 0; i < q->nr; i++) {
 494                struct diff_filepair *p = q->queue[i];
 495                if (!S_ISGITLINK(p->two->mode))
 496                        continue;
 497
 498                if (S_ISGITLINK(p->one->mode)) {
 499                        /* NEEDSWORK: We should honor the name configured in
 500                         * the .gitmodules file of the commit we are examining
 501                         * here to be able to correctly follow submodules
 502                         * being moved around. */
 503                        struct string_list_item *path;
 504                        path = unsorted_string_list_lookup(&changed_submodule_paths, p->two->path);
 505                        if (!path && !is_submodule_commit_present(p->two->path, p->two->sha1))
 506                                string_list_append(&changed_submodule_paths, xstrdup(p->two->path));
 507                } else {
 508                        /* Submodule is new or was moved here */
 509                        /* NEEDSWORK: When the .git directories of submodules
 510                         * live inside the superprojects .git directory some
 511                         * day we should fetch new submodules directly into
 512                         * that location too when config or options request
 513                         * that so they can be checked out from there. */
 514                        continue;
 515                }
 516        }
 517}
 518
 519static int add_sha1_to_array(const char *ref, const unsigned char *sha1,
 520                             int flags, void *data)
 521{
 522        sha1_array_append(data, sha1);
 523        return 0;
 524}
 525
 526void check_for_new_submodule_commits(unsigned char new_sha1[20])
 527{
 528        if (!initialized_fetch_ref_tips) {
 529                for_each_ref(add_sha1_to_array, &ref_tips_before_fetch);
 530                initialized_fetch_ref_tips = 1;
 531        }
 532
 533        sha1_array_append(&ref_tips_after_fetch, new_sha1);
 534}
 535
 536static void add_sha1_to_argv(const unsigned char sha1[20], void *data)
 537{
 538        argv_array_push(data, sha1_to_hex(sha1));
 539}
 540
 541static void calculate_changed_submodule_paths(void)
 542{
 543        struct rev_info rev;
 544        struct commit *commit;
 545        struct argv_array argv = ARGV_ARRAY_INIT;
 546
 547        /* No need to check if there are no submodules configured */
 548        if (!config_name_for_path.nr)
 549                return;
 550
 551        init_revisions(&rev, NULL);
 552        argv_array_push(&argv, "--"); /* argv[0] program name */
 553        sha1_array_for_each_unique(&ref_tips_after_fetch,
 554                                   add_sha1_to_argv, &argv);
 555        argv_array_push(&argv, "--not");
 556        sha1_array_for_each_unique(&ref_tips_before_fetch,
 557                                   add_sha1_to_argv, &argv);
 558        setup_revisions(argv.argc, argv.argv, &rev, NULL);
 559        if (prepare_revision_walk(&rev))
 560                die("revision walk setup failed");
 561
 562        /*
 563         * Collect all submodules (whether checked out or not) for which new
 564         * commits have been recorded upstream in "changed_submodule_paths".
 565         */
 566        while ((commit = get_revision(&rev))) {
 567                struct commit_list *parent = commit->parents;
 568                while (parent) {
 569                        struct diff_options diff_opts;
 570                        diff_setup(&diff_opts);
 571                        DIFF_OPT_SET(&diff_opts, RECURSIVE);
 572                        diff_opts.output_format |= DIFF_FORMAT_CALLBACK;
 573                        diff_opts.format_callback = submodule_collect_changed_cb;
 574                        if (diff_setup_done(&diff_opts) < 0)
 575                                die("diff_setup_done failed");
 576                        diff_tree_sha1(parent->item->object.sha1, commit->object.sha1, "", &diff_opts);
 577                        diffcore_std(&diff_opts);
 578                        diff_flush(&diff_opts);
 579                        parent = parent->next;
 580                }
 581        }
 582
 583        argv_array_clear(&argv);
 584        sha1_array_clear(&ref_tips_before_fetch);
 585        sha1_array_clear(&ref_tips_after_fetch);
 586        initialized_fetch_ref_tips = 0;
 587}
 588
 589int fetch_populated_submodules(int num_options, const char **options,
 590                               const char *prefix, int command_line_option,
 591                               int quiet)
 592{
 593        int i, result = 0, argc = 0, default_argc;
 594        struct child_process cp;
 595        const char **argv;
 596        struct string_list_item *name_for_path;
 597        const char *work_tree = get_git_work_tree();
 598        if (!work_tree)
 599                goto out;
 600
 601        if (!the_index.initialized)
 602                if (read_cache() < 0)
 603                        die("index file corrupt");
 604
 605        /* 6: "fetch" (options) --recurse-submodules-default default "--submodule-prefix" prefix NULL */
 606        argv = xcalloc(num_options + 6, sizeof(const char *));
 607        argv[argc++] = "fetch";
 608        for (i = 0; i < num_options; i++)
 609                argv[argc++] = options[i];
 610        argv[argc++] = "--recurse-submodules-default";
 611        default_argc = argc++;
 612        argv[argc++] = "--submodule-prefix";
 613
 614        memset(&cp, 0, sizeof(cp));
 615        cp.argv = argv;
 616        cp.env = local_repo_env;
 617        cp.git_cmd = 1;
 618        cp.no_stdin = 1;
 619
 620        calculate_changed_submodule_paths();
 621
 622        for (i = 0; i < active_nr; i++) {
 623                struct strbuf submodule_path = STRBUF_INIT;
 624                struct strbuf submodule_git_dir = STRBUF_INIT;
 625                struct strbuf submodule_prefix = STRBUF_INIT;
 626                struct cache_entry *ce = active_cache[i];
 627                const char *git_dir, *name, *default_argv;
 628
 629                if (!S_ISGITLINK(ce->ce_mode))
 630                        continue;
 631
 632                name = ce->name;
 633                name_for_path = unsorted_string_list_lookup(&config_name_for_path, ce->name);
 634                if (name_for_path)
 635                        name = name_for_path->util;
 636
 637                default_argv = "yes";
 638                if (command_line_option == RECURSE_SUBMODULES_DEFAULT) {
 639                        struct string_list_item *fetch_recurse_submodules_option;
 640                        fetch_recurse_submodules_option = unsorted_string_list_lookup(&config_fetch_recurse_submodules_for_name, name);
 641                        if (fetch_recurse_submodules_option) {
 642                                if ((intptr_t)fetch_recurse_submodules_option->util == RECURSE_SUBMODULES_OFF)
 643                                        continue;
 644                                if ((intptr_t)fetch_recurse_submodules_option->util == RECURSE_SUBMODULES_ON_DEMAND) {
 645                                        if (!unsorted_string_list_lookup(&changed_submodule_paths, ce->name))
 646                                                continue;
 647                                        default_argv = "on-demand";
 648                                }
 649                        } else {
 650                                if ((config_fetch_recurse_submodules == RECURSE_SUBMODULES_OFF) ||
 651                                    gitmodules_is_unmerged)
 652                                        continue;
 653                                if (config_fetch_recurse_submodules == RECURSE_SUBMODULES_ON_DEMAND) {
 654                                        if (!unsorted_string_list_lookup(&changed_submodule_paths, ce->name))
 655                                                continue;
 656                                        default_argv = "on-demand";
 657                                }
 658                        }
 659                } else if (command_line_option == RECURSE_SUBMODULES_ON_DEMAND) {
 660                        if (!unsorted_string_list_lookup(&changed_submodule_paths, ce->name))
 661                                continue;
 662                        default_argv = "on-demand";
 663                }
 664
 665                strbuf_addf(&submodule_path, "%s/%s", work_tree, ce->name);
 666                strbuf_addf(&submodule_git_dir, "%s/.git", submodule_path.buf);
 667                strbuf_addf(&submodule_prefix, "%s%s/", prefix, ce->name);
 668                git_dir = read_gitfile(submodule_git_dir.buf);
 669                if (!git_dir)
 670                        git_dir = submodule_git_dir.buf;
 671                if (is_directory(git_dir)) {
 672                        if (!quiet)
 673                                printf("Fetching submodule %s%s\n", prefix, ce->name);
 674                        cp.dir = submodule_path.buf;
 675                        argv[default_argc] = default_argv;
 676                        argv[argc] = submodule_prefix.buf;
 677                        if (run_command(&cp))
 678                                result = 1;
 679                }
 680                strbuf_release(&submodule_path);
 681                strbuf_release(&submodule_git_dir);
 682                strbuf_release(&submodule_prefix);
 683        }
 684        free(argv);
 685out:
 686        string_list_clear(&changed_submodule_paths, 1);
 687        return result;
 688}
 689
 690unsigned is_submodule_modified(const char *path, int ignore_untracked)
 691{
 692        ssize_t len;
 693        struct child_process cp;
 694        const char *argv[] = {
 695                "status",
 696                "--porcelain",
 697                NULL,
 698                NULL,
 699        };
 700        struct strbuf buf = STRBUF_INIT;
 701        unsigned dirty_submodule = 0;
 702        const char *line, *next_line;
 703        const char *git_dir;
 704
 705        strbuf_addf(&buf, "%s/.git", path);
 706        git_dir = read_gitfile(buf.buf);
 707        if (!git_dir)
 708                git_dir = buf.buf;
 709        if (!is_directory(git_dir)) {
 710                strbuf_release(&buf);
 711                /* The submodule is not checked out, so it is not modified */
 712                return 0;
 713
 714        }
 715        strbuf_reset(&buf);
 716
 717        if (ignore_untracked)
 718                argv[2] = "-uno";
 719
 720        memset(&cp, 0, sizeof(cp));
 721        cp.argv = argv;
 722        cp.env = local_repo_env;
 723        cp.git_cmd = 1;
 724        cp.no_stdin = 1;
 725        cp.out = -1;
 726        cp.dir = path;
 727        if (start_command(&cp))
 728                die("Could not run 'git status --porcelain' in submodule %s", path);
 729
 730        len = strbuf_read(&buf, cp.out, 1024);
 731        line = buf.buf;
 732        while (len > 2) {
 733                if ((line[0] == '?') && (line[1] == '?')) {
 734                        dirty_submodule |= DIRTY_SUBMODULE_UNTRACKED;
 735                        if (dirty_submodule & DIRTY_SUBMODULE_MODIFIED)
 736                                break;
 737                } else {
 738                        dirty_submodule |= DIRTY_SUBMODULE_MODIFIED;
 739                        if (ignore_untracked ||
 740                            (dirty_submodule & DIRTY_SUBMODULE_UNTRACKED))
 741                                break;
 742                }
 743                next_line = strchr(line, '\n');
 744                if (!next_line)
 745                        break;
 746                next_line++;
 747                len -= (next_line - line);
 748                line = next_line;
 749        }
 750        close(cp.out);
 751
 752        if (finish_command(&cp))
 753                die("'git status --porcelain' failed in submodule %s", path);
 754
 755        strbuf_release(&buf);
 756        return dirty_submodule;
 757}
 758
 759static int find_first_merges(struct object_array *result, const char *path,
 760                struct commit *a, struct commit *b)
 761{
 762        int i, j;
 763        struct object_array merges;
 764        struct commit *commit;
 765        int contains_another;
 766
 767        char merged_revision[42];
 768        const char *rev_args[] = { "rev-list", "--merges", "--ancestry-path",
 769                                   "--all", merged_revision, NULL };
 770        struct rev_info revs;
 771        struct setup_revision_opt rev_opts;
 772
 773        memset(&merges, 0, sizeof(merges));
 774        memset(result, 0, sizeof(struct object_array));
 775        memset(&rev_opts, 0, sizeof(rev_opts));
 776
 777        /* get all revisions that merge commit a */
 778        snprintf(merged_revision, sizeof(merged_revision), "^%s",
 779                        sha1_to_hex(a->object.sha1));
 780        init_revisions(&revs, NULL);
 781        rev_opts.submodule = path;
 782        setup_revisions(sizeof(rev_args)/sizeof(char *)-1, rev_args, &revs, &rev_opts);
 783
 784        /* save all revisions from the above list that contain b */
 785        if (prepare_revision_walk(&revs))
 786                die("revision walk setup failed");
 787        while ((commit = get_revision(&revs)) != NULL) {
 788                struct object *o = &(commit->object);
 789                if (in_merge_bases(b, &commit, 1))
 790                        add_object_array(o, NULL, &merges);
 791        }
 792        reset_revision_walk();
 793
 794        /* Now we've got all merges that contain a and b. Prune all
 795         * merges that contain another found merge and save them in
 796         * result.
 797         */
 798        for (i = 0; i < merges.nr; i++) {
 799                struct commit *m1 = (struct commit *) merges.objects[i].item;
 800
 801                contains_another = 0;
 802                for (j = 0; j < merges.nr; j++) {
 803                        struct commit *m2 = (struct commit *) merges.objects[j].item;
 804                        if (i != j && in_merge_bases(m2, &m1, 1)) {
 805                                contains_another = 1;
 806                                break;
 807                        }
 808                }
 809
 810                if (!contains_another)
 811                        add_object_array(merges.objects[i].item,
 812                                         merges.objects[i].name, result);
 813        }
 814
 815        free(merges.objects);
 816        return result->nr;
 817}
 818
 819static void print_commit(struct commit *commit)
 820{
 821        struct strbuf sb = STRBUF_INIT;
 822        struct pretty_print_context ctx = {0};
 823        ctx.date_mode = DATE_NORMAL;
 824        format_commit_message(commit, " %h: %m %s", &sb, &ctx);
 825        fprintf(stderr, "%s\n", sb.buf);
 826        strbuf_release(&sb);
 827}
 828
 829#define MERGE_WARNING(path, msg) \
 830        warning("Failed to merge submodule %s (%s)", path, msg);
 831
 832int merge_submodule(unsigned char result[20], const char *path,
 833                    const unsigned char base[20], const unsigned char a[20],
 834                    const unsigned char b[20], int search)
 835{
 836        struct commit *commit_base, *commit_a, *commit_b;
 837        int parent_count;
 838        struct object_array merges;
 839
 840        int i;
 841
 842        /* store a in result in case we fail */
 843        hashcpy(result, a);
 844
 845        /* we can not handle deletion conflicts */
 846        if (is_null_sha1(base))
 847                return 0;
 848        if (is_null_sha1(a))
 849                return 0;
 850        if (is_null_sha1(b))
 851                return 0;
 852
 853        if (add_submodule_odb(path)) {
 854                MERGE_WARNING(path, "not checked out");
 855                return 0;
 856        }
 857
 858        if (!(commit_base = lookup_commit_reference(base)) ||
 859            !(commit_a = lookup_commit_reference(a)) ||
 860            !(commit_b = lookup_commit_reference(b))) {
 861                MERGE_WARNING(path, "commits not present");
 862                return 0;
 863        }
 864
 865        /* check whether both changes are forward */
 866        if (!in_merge_bases(commit_base, &commit_a, 1) ||
 867            !in_merge_bases(commit_base, &commit_b, 1)) {
 868                MERGE_WARNING(path, "commits don't follow merge-base");
 869                return 0;
 870        }
 871
 872        /* Case #1: a is contained in b or vice versa */
 873        if (in_merge_bases(commit_a, &commit_b, 1)) {
 874                hashcpy(result, b);
 875                return 1;
 876        }
 877        if (in_merge_bases(commit_b, &commit_a, 1)) {
 878                hashcpy(result, a);
 879                return 1;
 880        }
 881
 882        /*
 883         * Case #2: There are one or more merges that contain a and b in
 884         * the submodule. If there is only one, then present it as a
 885         * suggestion to the user, but leave it marked unmerged so the
 886         * user needs to confirm the resolution.
 887         */
 888
 889        /* Skip the search if makes no sense to the calling context.  */
 890        if (!search)
 891                return 0;
 892
 893        /* find commit which merges them */
 894        parent_count = find_first_merges(&merges, path, commit_a, commit_b);
 895        switch (parent_count) {
 896        case 0:
 897                MERGE_WARNING(path, "merge following commits not found");
 898                break;
 899
 900        case 1:
 901                MERGE_WARNING(path, "not fast-forward");
 902                fprintf(stderr, "Found a possible merge resolution "
 903                                "for the submodule:\n");
 904                print_commit((struct commit *) merges.objects[0].item);
 905                fprintf(stderr,
 906                        "If this is correct simply add it to the index "
 907                        "for example\n"
 908                        "by using:\n\n"
 909                        "  git update-index --cacheinfo 160000 %s \"%s\"\n\n"
 910                        "which will accept this suggestion.\n",
 911                        sha1_to_hex(merges.objects[0].item->sha1), path);
 912                break;
 913
 914        default:
 915                MERGE_WARNING(path, "multiple merges found");
 916                for (i = 0; i < merges.nr; i++)
 917                        print_commit((struct commit *) merges.objects[i].item);
 918        }
 919
 920        free(merges.objects);
 921        return 0;
 922}