submodule.con commit Merge branch 'qp/bisect-docfix' (263fd04)
   1#include "cache.h"
   2#include "submodule-config.h"
   3#include "submodule.h"
   4#include "dir.h"
   5#include "diff.h"
   6#include "commit.h"
   7#include "revision.h"
   8#include "run-command.h"
   9#include "diffcore.h"
  10#include "refs.h"
  11#include "string-list.h"
  12#include "sha1-array.h"
  13#include "argv-array.h"
  14#include "blob.h"
  15#include "thread-utils.h"
  16#include "quote.h"
  17#include "worktree.h"
  18
  19static int config_fetch_recurse_submodules = RECURSE_SUBMODULES_ON_DEMAND;
  20static int config_update_recurse_submodules = RECURSE_SUBMODULES_DEFAULT;
  21static int parallel_jobs = 1;
  22static struct string_list changed_submodule_paths = STRING_LIST_INIT_NODUP;
  23static int initialized_fetch_ref_tips;
  24static struct sha1_array ref_tips_before_fetch;
  25static struct sha1_array ref_tips_after_fetch;
  26
  27/*
  28 * The following flag is set if the .gitmodules file is unmerged. We then
  29 * disable recursion for all submodules where .git/config doesn't have a
  30 * matching config entry because we can't guess what might be configured in
  31 * .gitmodules unless the user resolves the conflict. When a command line
  32 * option is given (which always overrides configuration) this flag will be
  33 * ignored.
  34 */
  35static int gitmodules_is_unmerged;
  36
  37/*
  38 * This flag is set if the .gitmodules file had unstaged modifications on
  39 * startup. This must be checked before allowing modifications to the
  40 * .gitmodules file with the intention to stage them later, because when
  41 * continuing we would stage the modifications the user didn't stage herself
  42 * too. That might change in a future version when we learn to stage the
  43 * changes we do ourselves without staging any previous modifications.
  44 */
  45static int gitmodules_is_modified;
  46
  47int is_staging_gitmodules_ok(void)
  48{
  49        return !gitmodules_is_modified;
  50}
  51
  52/*
  53 * Try to update the "path" entry in the "submodule.<name>" section of the
  54 * .gitmodules file. Return 0 only if a .gitmodules file was found, a section
  55 * with the correct path=<oldpath> setting was found and we could update it.
  56 */
  57int update_path_in_gitmodules(const char *oldpath, const char *newpath)
  58{
  59        struct strbuf entry = STRBUF_INIT;
  60        const struct submodule *submodule;
  61
  62        if (!file_exists(".gitmodules")) /* Do nothing without .gitmodules */
  63                return -1;
  64
  65        if (gitmodules_is_unmerged)
  66                die(_("Cannot change unmerged .gitmodules, resolve merge conflicts first"));
  67
  68        submodule = submodule_from_path(null_sha1, oldpath);
  69        if (!submodule || !submodule->name) {
  70                warning(_("Could not find section in .gitmodules where path=%s"), oldpath);
  71                return -1;
  72        }
  73        strbuf_addstr(&entry, "submodule.");
  74        strbuf_addstr(&entry, submodule->name);
  75        strbuf_addstr(&entry, ".path");
  76        if (git_config_set_in_file_gently(".gitmodules", entry.buf, newpath) < 0) {
  77                /* Maybe the user already did that, don't error out here */
  78                warning(_("Could not update .gitmodules entry %s"), entry.buf);
  79                strbuf_release(&entry);
  80                return -1;
  81        }
  82        strbuf_release(&entry);
  83        return 0;
  84}
  85
  86/*
  87 * Try to remove the "submodule.<name>" section from .gitmodules where the given
  88 * path is configured. Return 0 only if a .gitmodules file was found, a section
  89 * with the correct path=<path> setting was found and we could remove it.
  90 */
  91int remove_path_from_gitmodules(const char *path)
  92{
  93        struct strbuf sect = STRBUF_INIT;
  94        const struct submodule *submodule;
  95
  96        if (!file_exists(".gitmodules")) /* Do nothing without .gitmodules */
  97                return -1;
  98
  99        if (gitmodules_is_unmerged)
 100                die(_("Cannot change unmerged .gitmodules, resolve merge conflicts first"));
 101
 102        submodule = submodule_from_path(null_sha1, path);
 103        if (!submodule || !submodule->name) {
 104                warning(_("Could not find section in .gitmodules where path=%s"), path);
 105                return -1;
 106        }
 107        strbuf_addstr(&sect, "submodule.");
 108        strbuf_addstr(&sect, submodule->name);
 109        if (git_config_rename_section_in_file(".gitmodules", sect.buf, NULL) < 0) {
 110                /* Maybe the user already did that, don't error out here */
 111                warning(_("Could not remove .gitmodules entry for %s"), path);
 112                strbuf_release(&sect);
 113                return -1;
 114        }
 115        strbuf_release(&sect);
 116        return 0;
 117}
 118
 119void stage_updated_gitmodules(void)
 120{
 121        if (add_file_to_cache(".gitmodules", 0))
 122                die(_("staging updated .gitmodules failed"));
 123}
 124
 125static int add_submodule_odb(const char *path)
 126{
 127        struct strbuf objects_directory = STRBUF_INIT;
 128        int ret = 0;
 129
 130        ret = strbuf_git_path_submodule(&objects_directory, path, "objects/");
 131        if (ret)
 132                goto done;
 133        if (!is_directory(objects_directory.buf)) {
 134                ret = -1;
 135                goto done;
 136        }
 137        add_to_alternates_memory(objects_directory.buf);
 138done:
 139        strbuf_release(&objects_directory);
 140        return ret;
 141}
 142
 143void set_diffopt_flags_from_submodule_config(struct diff_options *diffopt,
 144                                             const char *path)
 145{
 146        const struct submodule *submodule = submodule_from_path(null_sha1, path);
 147        if (submodule) {
 148                if (submodule->ignore)
 149                        handle_ignore_submodules_arg(diffopt, submodule->ignore);
 150                else if (gitmodules_is_unmerged)
 151                        DIFF_OPT_SET(diffopt, IGNORE_SUBMODULES);
 152        }
 153}
 154
 155int submodule_config(const char *var, const char *value, void *cb)
 156{
 157        if (!strcmp(var, "submodule.fetchjobs")) {
 158                parallel_jobs = git_config_int(var, value);
 159                if (parallel_jobs < 0)
 160                        die(_("negative values not allowed for submodule.fetchJobs"));
 161                return 0;
 162        } else if (starts_with(var, "submodule."))
 163                return parse_submodule_config_option(var, value);
 164        else if (!strcmp(var, "fetch.recursesubmodules")) {
 165                config_fetch_recurse_submodules = parse_fetch_recurse_submodules_arg(var, value);
 166                return 0;
 167        }
 168        return 0;
 169}
 170
 171void gitmodules_config(void)
 172{
 173        const char *work_tree = get_git_work_tree();
 174        if (work_tree) {
 175                struct strbuf gitmodules_path = STRBUF_INIT;
 176                int pos;
 177                strbuf_addstr(&gitmodules_path, work_tree);
 178                strbuf_addstr(&gitmodules_path, "/.gitmodules");
 179                if (read_cache() < 0)
 180                        die("index file corrupt");
 181                pos = cache_name_pos(".gitmodules", 11);
 182                if (pos < 0) { /* .gitmodules not found or isn't merged */
 183                        pos = -1 - pos;
 184                        if (active_nr > pos) {  /* there is a .gitmodules */
 185                                const struct cache_entry *ce = active_cache[pos];
 186                                if (ce_namelen(ce) == 11 &&
 187                                    !memcmp(ce->name, ".gitmodules", 11))
 188                                        gitmodules_is_unmerged = 1;
 189                        }
 190                } else if (pos < active_nr) {
 191                        struct stat st;
 192                        if (lstat(".gitmodules", &st) == 0 &&
 193                            ce_match_stat(active_cache[pos], &st, 0) & DATA_CHANGED)
 194                                gitmodules_is_modified = 1;
 195                }
 196
 197                if (!gitmodules_is_unmerged)
 198                        git_config_from_file(submodule_config, gitmodules_path.buf, NULL);
 199                strbuf_release(&gitmodules_path);
 200        }
 201}
 202
 203void gitmodules_config_sha1(const unsigned char *commit_sha1)
 204{
 205        struct strbuf rev = STRBUF_INIT;
 206        unsigned char sha1[20];
 207
 208        if (gitmodule_sha1_from_commit(commit_sha1, sha1, &rev)) {
 209                git_config_from_blob_sha1(submodule_config, rev.buf,
 210                                          sha1, NULL);
 211        }
 212        strbuf_release(&rev);
 213}
 214
 215/*
 216 * NEEDSWORK: With the addition of different configuration options to determine
 217 * if a submodule is of interests, the validity of this function's name comes
 218 * into question.  Once the dust has settled and more concrete terminology is
 219 * decided upon, come up with a more proper name for this function.  One
 220 * potential candidate could be 'is_submodule_active()'.
 221 *
 222 * Determine if a submodule has been initialized at a given 'path'
 223 */
 224int is_submodule_initialized(const char *path)
 225{
 226        int ret = 0;
 227        char *key = NULL;
 228        char *value = NULL;
 229        const struct string_list *sl;
 230        const struct submodule *module = submodule_from_path(null_sha1, path);
 231
 232        /* early return if there isn't a path->module mapping */
 233        if (!module)
 234                return 0;
 235
 236        /* submodule.<name>.active is set */
 237        key = xstrfmt("submodule.%s.active", module->name);
 238        if (!git_config_get_bool(key, &ret)) {
 239                free(key);
 240                return ret;
 241        }
 242        free(key);
 243
 244        /* submodule.active is set */
 245        sl = git_config_get_value_multi("submodule.active");
 246        if (sl) {
 247                struct pathspec ps;
 248                struct argv_array args = ARGV_ARRAY_INIT;
 249                const struct string_list_item *item;
 250
 251                for_each_string_list_item(item, sl) {
 252                        argv_array_push(&args, item->string);
 253                }
 254
 255                parse_pathspec(&ps, 0, 0, NULL, args.argv);
 256                ret = match_pathspec(&ps, path, strlen(path), 0, NULL, 1);
 257
 258                argv_array_clear(&args);
 259                clear_pathspec(&ps);
 260                return ret;
 261        }
 262
 263        /* fallback to checking if the URL is set */
 264        key = xstrfmt("submodule.%s.url", module->name);
 265        ret = !git_config_get_string(key, &value);
 266
 267        free(value);
 268        free(key);
 269        return ret;
 270}
 271
 272int is_submodule_populated_gently(const char *path, int *return_error_code)
 273{
 274        int ret = 0;
 275        char *gitdir = xstrfmt("%s/.git", path);
 276
 277        if (resolve_gitdir_gently(gitdir, return_error_code))
 278                ret = 1;
 279
 280        free(gitdir);
 281        return ret;
 282}
 283
 284int parse_submodule_update_strategy(const char *value,
 285                struct submodule_update_strategy *dst)
 286{
 287        free((void*)dst->command);
 288        dst->command = NULL;
 289        if (!strcmp(value, "none"))
 290                dst->type = SM_UPDATE_NONE;
 291        else if (!strcmp(value, "checkout"))
 292                dst->type = SM_UPDATE_CHECKOUT;
 293        else if (!strcmp(value, "rebase"))
 294                dst->type = SM_UPDATE_REBASE;
 295        else if (!strcmp(value, "merge"))
 296                dst->type = SM_UPDATE_MERGE;
 297        else if (skip_prefix(value, "!", &value)) {
 298                dst->type = SM_UPDATE_COMMAND;
 299                dst->command = xstrdup(value);
 300        } else
 301                return -1;
 302        return 0;
 303}
 304
 305const char *submodule_strategy_to_string(const struct submodule_update_strategy *s)
 306{
 307        struct strbuf sb = STRBUF_INIT;
 308        switch (s->type) {
 309        case SM_UPDATE_CHECKOUT:
 310                return "checkout";
 311        case SM_UPDATE_MERGE:
 312                return "merge";
 313        case SM_UPDATE_REBASE:
 314                return "rebase";
 315        case SM_UPDATE_NONE:
 316                return "none";
 317        case SM_UPDATE_UNSPECIFIED:
 318                return NULL;
 319        case SM_UPDATE_COMMAND:
 320                strbuf_addf(&sb, "!%s", s->command);
 321                return strbuf_detach(&sb, NULL);
 322        }
 323        return NULL;
 324}
 325
 326void handle_ignore_submodules_arg(struct diff_options *diffopt,
 327                                  const char *arg)
 328{
 329        DIFF_OPT_CLR(diffopt, IGNORE_SUBMODULES);
 330        DIFF_OPT_CLR(diffopt, IGNORE_UNTRACKED_IN_SUBMODULES);
 331        DIFF_OPT_CLR(diffopt, IGNORE_DIRTY_SUBMODULES);
 332
 333        if (!strcmp(arg, "all"))
 334                DIFF_OPT_SET(diffopt, IGNORE_SUBMODULES);
 335        else if (!strcmp(arg, "untracked"))
 336                DIFF_OPT_SET(diffopt, IGNORE_UNTRACKED_IN_SUBMODULES);
 337        else if (!strcmp(arg, "dirty"))
 338                DIFF_OPT_SET(diffopt, IGNORE_DIRTY_SUBMODULES);
 339        else if (strcmp(arg, "none"))
 340                die("bad --ignore-submodules argument: %s", arg);
 341}
 342
 343static int prepare_submodule_summary(struct rev_info *rev, const char *path,
 344                struct commit *left, struct commit *right,
 345                struct commit_list *merge_bases)
 346{
 347        struct commit_list *list;
 348
 349        init_revisions(rev, NULL);
 350        setup_revisions(0, NULL, rev, NULL);
 351        rev->left_right = 1;
 352        rev->first_parent_only = 1;
 353        left->object.flags |= SYMMETRIC_LEFT;
 354        add_pending_object(rev, &left->object, path);
 355        add_pending_object(rev, &right->object, path);
 356        for (list = merge_bases; list; list = list->next) {
 357                list->item->object.flags |= UNINTERESTING;
 358                add_pending_object(rev, &list->item->object,
 359                        oid_to_hex(&list->item->object.oid));
 360        }
 361        return prepare_revision_walk(rev);
 362}
 363
 364static void print_submodule_summary(struct rev_info *rev, FILE *f,
 365                const char *line_prefix,
 366                const char *del, const char *add, const char *reset)
 367{
 368        static const char format[] = "  %m %s";
 369        struct strbuf sb = STRBUF_INIT;
 370        struct commit *commit;
 371
 372        while ((commit = get_revision(rev))) {
 373                struct pretty_print_context ctx = {0};
 374                ctx.date_mode = rev->date_mode;
 375                ctx.output_encoding = get_log_output_encoding();
 376                strbuf_setlen(&sb, 0);
 377                strbuf_addstr(&sb, line_prefix);
 378                if (commit->object.flags & SYMMETRIC_LEFT) {
 379                        if (del)
 380                                strbuf_addstr(&sb, del);
 381                }
 382                else if (add)
 383                        strbuf_addstr(&sb, add);
 384                format_commit_message(commit, format, &sb, &ctx);
 385                if (reset)
 386                        strbuf_addstr(&sb, reset);
 387                strbuf_addch(&sb, '\n');
 388                fprintf(f, "%s", sb.buf);
 389        }
 390        strbuf_release(&sb);
 391}
 392
 393static void prepare_submodule_repo_env_no_git_dir(struct argv_array *out)
 394{
 395        const char * const *var;
 396
 397        for (var = local_repo_env; *var; var++) {
 398                if (strcmp(*var, CONFIG_DATA_ENVIRONMENT))
 399                        argv_array_push(out, *var);
 400        }
 401}
 402
 403void prepare_submodule_repo_env(struct argv_array *out)
 404{
 405        prepare_submodule_repo_env_no_git_dir(out);
 406        argv_array_pushf(out, "%s=%s", GIT_DIR_ENVIRONMENT,
 407                         DEFAULT_GIT_DIR_ENVIRONMENT);
 408}
 409
 410/* Helper function to display the submodule header line prior to the full
 411 * summary output. If it can locate the submodule objects directory it will
 412 * attempt to lookup both the left and right commits and put them into the
 413 * left and right pointers.
 414 */
 415static void show_submodule_header(FILE *f, const char *path,
 416                const char *line_prefix,
 417                struct object_id *one, struct object_id *two,
 418                unsigned dirty_submodule, const char *meta,
 419                const char *reset,
 420                struct commit **left, struct commit **right,
 421                struct commit_list **merge_bases)
 422{
 423        const char *message = NULL;
 424        struct strbuf sb = STRBUF_INIT;
 425        int fast_forward = 0, fast_backward = 0;
 426
 427        if (dirty_submodule & DIRTY_SUBMODULE_UNTRACKED)
 428                fprintf(f, "%sSubmodule %s contains untracked content\n",
 429                        line_prefix, path);
 430        if (dirty_submodule & DIRTY_SUBMODULE_MODIFIED)
 431                fprintf(f, "%sSubmodule %s contains modified content\n",
 432                        line_prefix, path);
 433
 434        if (is_null_oid(one))
 435                message = "(new submodule)";
 436        else if (is_null_oid(two))
 437                message = "(submodule deleted)";
 438
 439        if (add_submodule_odb(path)) {
 440                if (!message)
 441                        message = "(not initialized)";
 442                goto output_header;
 443        }
 444
 445        /*
 446         * Attempt to lookup the commit references, and determine if this is
 447         * a fast forward or fast backwards update.
 448         */
 449        *left = lookup_commit_reference(one->hash);
 450        *right = lookup_commit_reference(two->hash);
 451
 452        /*
 453         * Warn about missing commits in the submodule project, but only if
 454         * they aren't null.
 455         */
 456        if ((!is_null_oid(one) && !*left) ||
 457             (!is_null_oid(two) && !*right))
 458                message = "(commits not present)";
 459
 460        *merge_bases = get_merge_bases(*left, *right);
 461        if (*merge_bases) {
 462                if ((*merge_bases)->item == *left)
 463                        fast_forward = 1;
 464                else if ((*merge_bases)->item == *right)
 465                        fast_backward = 1;
 466        }
 467
 468        if (!oidcmp(one, two)) {
 469                strbuf_release(&sb);
 470                return;
 471        }
 472
 473output_header:
 474        strbuf_addf(&sb, "%s%sSubmodule %s ", line_prefix, meta, path);
 475        strbuf_add_unique_abbrev(&sb, one->hash, DEFAULT_ABBREV);
 476        strbuf_addstr(&sb, (fast_backward || fast_forward) ? ".." : "...");
 477        strbuf_add_unique_abbrev(&sb, two->hash, DEFAULT_ABBREV);
 478        if (message)
 479                strbuf_addf(&sb, " %s%s\n", message, reset);
 480        else
 481                strbuf_addf(&sb, "%s:%s\n", fast_backward ? " (rewind)" : "", reset);
 482        fwrite(sb.buf, sb.len, 1, f);
 483
 484        strbuf_release(&sb);
 485}
 486
 487void show_submodule_summary(FILE *f, const char *path,
 488                const char *line_prefix,
 489                struct object_id *one, struct object_id *two,
 490                unsigned dirty_submodule, const char *meta,
 491                const char *del, const char *add, const char *reset)
 492{
 493        struct rev_info rev;
 494        struct commit *left = NULL, *right = NULL;
 495        struct commit_list *merge_bases = NULL;
 496
 497        show_submodule_header(f, path, line_prefix, one, two, dirty_submodule,
 498                              meta, reset, &left, &right, &merge_bases);
 499
 500        /*
 501         * If we don't have both a left and a right pointer, there is no
 502         * reason to try and display a summary. The header line should contain
 503         * all the information the user needs.
 504         */
 505        if (!left || !right)
 506                goto out;
 507
 508        /* Treat revision walker failure the same as missing commits */
 509        if (prepare_submodule_summary(&rev, path, left, right, merge_bases)) {
 510                fprintf(f, "%s(revision walker failed)\n", line_prefix);
 511                goto out;
 512        }
 513
 514        print_submodule_summary(&rev, f, line_prefix, del, add, reset);
 515
 516out:
 517        if (merge_bases)
 518                free_commit_list(merge_bases);
 519        clear_commit_marks(left, ~0);
 520        clear_commit_marks(right, ~0);
 521}
 522
 523void show_submodule_inline_diff(FILE *f, const char *path,
 524                const char *line_prefix,
 525                struct object_id *one, struct object_id *two,
 526                unsigned dirty_submodule, const char *meta,
 527                const char *del, const char *add, const char *reset,
 528                const struct diff_options *o)
 529{
 530        const struct object_id *old = &empty_tree_oid, *new = &empty_tree_oid;
 531        struct commit *left = NULL, *right = NULL;
 532        struct commit_list *merge_bases = NULL;
 533        struct strbuf submodule_dir = STRBUF_INIT;
 534        struct child_process cp = CHILD_PROCESS_INIT;
 535
 536        show_submodule_header(f, path, line_prefix, one, two, dirty_submodule,
 537                              meta, reset, &left, &right, &merge_bases);
 538
 539        /* We need a valid left and right commit to display a difference */
 540        if (!(left || is_null_oid(one)) ||
 541            !(right || is_null_oid(two)))
 542                goto done;
 543
 544        if (left)
 545                old = one;
 546        if (right)
 547                new = two;
 548
 549        fflush(f);
 550        cp.git_cmd = 1;
 551        cp.dir = path;
 552        cp.out = dup(fileno(f));
 553        cp.no_stdin = 1;
 554
 555        /* TODO: other options may need to be passed here. */
 556        argv_array_push(&cp.args, "diff");
 557        argv_array_pushf(&cp.args, "--line-prefix=%s", line_prefix);
 558        if (DIFF_OPT_TST(o, REVERSE_DIFF)) {
 559                argv_array_pushf(&cp.args, "--src-prefix=%s%s/",
 560                                 o->b_prefix, path);
 561                argv_array_pushf(&cp.args, "--dst-prefix=%s%s/",
 562                                 o->a_prefix, path);
 563        } else {
 564                argv_array_pushf(&cp.args, "--src-prefix=%s%s/",
 565                                 o->a_prefix, path);
 566                argv_array_pushf(&cp.args, "--dst-prefix=%s%s/",
 567                                 o->b_prefix, path);
 568        }
 569        argv_array_push(&cp.args, oid_to_hex(old));
 570        /*
 571         * If the submodule has modified content, we will diff against the
 572         * work tree, under the assumption that the user has asked for the
 573         * diff format and wishes to actually see all differences even if they
 574         * haven't yet been committed to the submodule yet.
 575         */
 576        if (!(dirty_submodule & DIRTY_SUBMODULE_MODIFIED))
 577                argv_array_push(&cp.args, oid_to_hex(new));
 578
 579        if (run_command(&cp))
 580                fprintf(f, "(diff failed)\n");
 581
 582done:
 583        strbuf_release(&submodule_dir);
 584        if (merge_bases)
 585                free_commit_list(merge_bases);
 586        if (left)
 587                clear_commit_marks(left, ~0);
 588        if (right)
 589                clear_commit_marks(right, ~0);
 590}
 591
 592void set_config_fetch_recurse_submodules(int value)
 593{
 594        config_fetch_recurse_submodules = value;
 595}
 596
 597void set_config_update_recurse_submodules(int value)
 598{
 599        config_update_recurse_submodules = value;
 600}
 601
 602int should_update_submodules(void)
 603{
 604        return config_update_recurse_submodules == RECURSE_SUBMODULES_ON;
 605}
 606
 607const struct submodule *submodule_from_ce(const struct cache_entry *ce)
 608{
 609        if (!S_ISGITLINK(ce->ce_mode))
 610                return NULL;
 611
 612        if (!should_update_submodules())
 613                return NULL;
 614
 615        return submodule_from_path(null_sha1, ce->name);
 616}
 617
 618static int has_remote(const char *refname, const struct object_id *oid,
 619                      int flags, void *cb_data)
 620{
 621        return 1;
 622}
 623
 624static int append_sha1_to_argv(const unsigned char sha1[20], void *data)
 625{
 626        struct argv_array *argv = data;
 627        argv_array_push(argv, sha1_to_hex(sha1));
 628        return 0;
 629}
 630
 631static int check_has_commit(const unsigned char sha1[20], void *data)
 632{
 633        int *has_commit = data;
 634
 635        if (!lookup_commit_reference(sha1))
 636                *has_commit = 0;
 637
 638        return 0;
 639}
 640
 641static int submodule_has_commits(const char *path, struct sha1_array *commits)
 642{
 643        int has_commit = 1;
 644
 645        if (add_submodule_odb(path))
 646                return 0;
 647
 648        sha1_array_for_each_unique(commits, check_has_commit, &has_commit);
 649        return has_commit;
 650}
 651
 652static int submodule_needs_pushing(const char *path, struct sha1_array *commits)
 653{
 654        if (!submodule_has_commits(path, commits))
 655                /*
 656                 * NOTE: We do consider it safe to return "no" here. The
 657                 * correct answer would be "We do not know" instead of
 658                 * "No push needed", but it is quite hard to change
 659                 * the submodule pointer without having the submodule
 660                 * around. If a user did however change the submodules
 661                 * without having the submodule around, this indicates
 662                 * an expert who knows what they are doing or a
 663                 * maintainer integrating work from other people. In
 664                 * both cases it should be safe to skip this check.
 665                 */
 666                return 0;
 667
 668        if (for_each_remote_ref_submodule(path, has_remote, NULL) > 0) {
 669                struct child_process cp = CHILD_PROCESS_INIT;
 670                struct strbuf buf = STRBUF_INIT;
 671                int needs_pushing = 0;
 672
 673                argv_array_push(&cp.args, "rev-list");
 674                sha1_array_for_each_unique(commits, append_sha1_to_argv, &cp.args);
 675                argv_array_pushl(&cp.args, "--not", "--remotes", "-n", "1" , NULL);
 676
 677                prepare_submodule_repo_env(&cp.env_array);
 678                cp.git_cmd = 1;
 679                cp.no_stdin = 1;
 680                cp.out = -1;
 681                cp.dir = path;
 682                if (start_command(&cp))
 683                        die("Could not run 'git rev-list <commits> --not --remotes -n 1' command in submodule %s",
 684                                        path);
 685                if (strbuf_read(&buf, cp.out, 41))
 686                        needs_pushing = 1;
 687                finish_command(&cp);
 688                close(cp.out);
 689                strbuf_release(&buf);
 690                return needs_pushing;
 691        }
 692
 693        return 0;
 694}
 695
 696static struct sha1_array *submodule_commits(struct string_list *submodules,
 697                                            const char *path)
 698{
 699        struct string_list_item *item;
 700
 701        item = string_list_insert(submodules, path);
 702        if (item->util)
 703                return (struct sha1_array *) item->util;
 704
 705        /* NEEDSWORK: should we have sha1_array_init()? */
 706        item->util = xcalloc(1, sizeof(struct sha1_array));
 707        return (struct sha1_array *) item->util;
 708}
 709
 710static void collect_submodules_from_diff(struct diff_queue_struct *q,
 711                                         struct diff_options *options,
 712                                         void *data)
 713{
 714        int i;
 715        struct string_list *submodules = data;
 716
 717        for (i = 0; i < q->nr; i++) {
 718                struct diff_filepair *p = q->queue[i];
 719                struct sha1_array *commits;
 720                if (!S_ISGITLINK(p->two->mode))
 721                        continue;
 722                commits = submodule_commits(submodules, p->two->path);
 723                sha1_array_append(commits, p->two->oid.hash);
 724        }
 725}
 726
 727static void find_unpushed_submodule_commits(struct commit *commit,
 728                struct string_list *needs_pushing)
 729{
 730        struct rev_info rev;
 731
 732        init_revisions(&rev, NULL);
 733        rev.diffopt.output_format |= DIFF_FORMAT_CALLBACK;
 734        rev.diffopt.format_callback = collect_submodules_from_diff;
 735        rev.diffopt.format_callback_data = needs_pushing;
 736        diff_tree_combined_merge(commit, 1, &rev);
 737}
 738
 739static void free_submodules_sha1s(struct string_list *submodules)
 740{
 741        struct string_list_item *item;
 742        for_each_string_list_item(item, submodules)
 743                sha1_array_clear((struct sha1_array *) item->util);
 744        string_list_clear(submodules, 1);
 745}
 746
 747int find_unpushed_submodules(struct sha1_array *commits,
 748                const char *remotes_name, struct string_list *needs_pushing)
 749{
 750        struct rev_info rev;
 751        struct commit *commit;
 752        struct string_list submodules = STRING_LIST_INIT_DUP;
 753        struct string_list_item *submodule;
 754        struct argv_array argv = ARGV_ARRAY_INIT;
 755
 756        init_revisions(&rev, NULL);
 757
 758        /* argv.argv[0] will be ignored by setup_revisions */
 759        argv_array_push(&argv, "find_unpushed_submodules");
 760        sha1_array_for_each_unique(commits, append_sha1_to_argv, &argv);
 761        argv_array_push(&argv, "--not");
 762        argv_array_pushf(&argv, "--remotes=%s", remotes_name);
 763
 764        setup_revisions(argv.argc, argv.argv, &rev, NULL);
 765        if (prepare_revision_walk(&rev))
 766                die("revision walk setup failed");
 767
 768        while ((commit = get_revision(&rev)) != NULL)
 769                find_unpushed_submodule_commits(commit, &submodules);
 770
 771        reset_revision_walk();
 772        argv_array_clear(&argv);
 773
 774        for_each_string_list_item(submodule, &submodules) {
 775                struct sha1_array *commits = (struct sha1_array *) submodule->util;
 776
 777                if (submodule_needs_pushing(submodule->string, commits))
 778                        string_list_insert(needs_pushing, submodule->string);
 779        }
 780        free_submodules_sha1s(&submodules);
 781
 782        return needs_pushing->nr;
 783}
 784
 785static int push_submodule(const char *path, int dry_run)
 786{
 787        if (add_submodule_odb(path))
 788                return 1;
 789
 790        if (for_each_remote_ref_submodule(path, has_remote, NULL) > 0) {
 791                struct child_process cp = CHILD_PROCESS_INIT;
 792                argv_array_push(&cp.args, "push");
 793                if (dry_run)
 794                        argv_array_push(&cp.args, "--dry-run");
 795
 796                prepare_submodule_repo_env(&cp.env_array);
 797                cp.git_cmd = 1;
 798                cp.no_stdin = 1;
 799                cp.dir = path;
 800                if (run_command(&cp))
 801                        return 0;
 802                close(cp.out);
 803        }
 804
 805        return 1;
 806}
 807
 808int push_unpushed_submodules(struct sha1_array *commits,
 809                             const char *remotes_name,
 810                             int dry_run)
 811{
 812        int i, ret = 1;
 813        struct string_list needs_pushing = STRING_LIST_INIT_DUP;
 814
 815        if (!find_unpushed_submodules(commits, remotes_name, &needs_pushing))
 816                return 1;
 817
 818        for (i = 0; i < needs_pushing.nr; i++) {
 819                const char *path = needs_pushing.items[i].string;
 820                fprintf(stderr, "Pushing submodule '%s'\n", path);
 821                if (!push_submodule(path, dry_run)) {
 822                        fprintf(stderr, "Unable to push submodule '%s'\n", path);
 823                        ret = 0;
 824                }
 825        }
 826
 827        string_list_clear(&needs_pushing, 0);
 828
 829        return ret;
 830}
 831
 832static int is_submodule_commit_present(const char *path, unsigned char sha1[20])
 833{
 834        int is_present = 0;
 835        if (!add_submodule_odb(path) && lookup_commit_reference(sha1)) {
 836                /* Even if the submodule is checked out and the commit is
 837                 * present, make sure it is reachable from a ref. */
 838                struct child_process cp = CHILD_PROCESS_INIT;
 839                const char *argv[] = {"rev-list", "-n", "1", NULL, "--not", "--all", NULL};
 840                struct strbuf buf = STRBUF_INIT;
 841
 842                argv[3] = sha1_to_hex(sha1);
 843                cp.argv = argv;
 844                prepare_submodule_repo_env(&cp.env_array);
 845                cp.git_cmd = 1;
 846                cp.no_stdin = 1;
 847                cp.dir = path;
 848                if (!capture_command(&cp, &buf, 1024) && !buf.len)
 849                        is_present = 1;
 850
 851                strbuf_release(&buf);
 852        }
 853        return is_present;
 854}
 855
 856static void submodule_collect_changed_cb(struct diff_queue_struct *q,
 857                                         struct diff_options *options,
 858                                         void *data)
 859{
 860        int i;
 861        for (i = 0; i < q->nr; i++) {
 862                struct diff_filepair *p = q->queue[i];
 863                if (!S_ISGITLINK(p->two->mode))
 864                        continue;
 865
 866                if (S_ISGITLINK(p->one->mode)) {
 867                        /* NEEDSWORK: We should honor the name configured in
 868                         * the .gitmodules file of the commit we are examining
 869                         * here to be able to correctly follow submodules
 870                         * being moved around. */
 871                        struct string_list_item *path;
 872                        path = unsorted_string_list_lookup(&changed_submodule_paths, p->two->path);
 873                        if (!path && !is_submodule_commit_present(p->two->path, p->two->oid.hash))
 874                                string_list_append(&changed_submodule_paths, xstrdup(p->two->path));
 875                } else {
 876                        /* Submodule is new or was moved here */
 877                        /* NEEDSWORK: When the .git directories of submodules
 878                         * live inside the superprojects .git directory some
 879                         * day we should fetch new submodules directly into
 880                         * that location too when config or options request
 881                         * that so they can be checked out from there. */
 882                        continue;
 883                }
 884        }
 885}
 886
 887static int add_sha1_to_array(const char *ref, const struct object_id *oid,
 888                             int flags, void *data)
 889{
 890        sha1_array_append(data, oid->hash);
 891        return 0;
 892}
 893
 894void check_for_new_submodule_commits(unsigned char new_sha1[20])
 895{
 896        if (!initialized_fetch_ref_tips) {
 897                for_each_ref(add_sha1_to_array, &ref_tips_before_fetch);
 898                initialized_fetch_ref_tips = 1;
 899        }
 900
 901        sha1_array_append(&ref_tips_after_fetch, new_sha1);
 902}
 903
 904static int add_sha1_to_argv(const unsigned char sha1[20], void *data)
 905{
 906        argv_array_push(data, sha1_to_hex(sha1));
 907        return 0;
 908}
 909
 910static void calculate_changed_submodule_paths(void)
 911{
 912        struct rev_info rev;
 913        struct commit *commit;
 914        struct argv_array argv = ARGV_ARRAY_INIT;
 915
 916        /* No need to check if there are no submodules configured */
 917        if (!submodule_from_path(NULL, NULL))
 918                return;
 919
 920        init_revisions(&rev, NULL);
 921        argv_array_push(&argv, "--"); /* argv[0] program name */
 922        sha1_array_for_each_unique(&ref_tips_after_fetch,
 923                                   add_sha1_to_argv, &argv);
 924        argv_array_push(&argv, "--not");
 925        sha1_array_for_each_unique(&ref_tips_before_fetch,
 926                                   add_sha1_to_argv, &argv);
 927        setup_revisions(argv.argc, argv.argv, &rev, NULL);
 928        if (prepare_revision_walk(&rev))
 929                die("revision walk setup failed");
 930
 931        /*
 932         * Collect all submodules (whether checked out or not) for which new
 933         * commits have been recorded upstream in "changed_submodule_paths".
 934         */
 935        while ((commit = get_revision(&rev))) {
 936                struct commit_list *parent = commit->parents;
 937                while (parent) {
 938                        struct diff_options diff_opts;
 939                        diff_setup(&diff_opts);
 940                        DIFF_OPT_SET(&diff_opts, RECURSIVE);
 941                        diff_opts.output_format |= DIFF_FORMAT_CALLBACK;
 942                        diff_opts.format_callback = submodule_collect_changed_cb;
 943                        diff_setup_done(&diff_opts);
 944                        diff_tree_sha1(parent->item->object.oid.hash, commit->object.oid.hash, "", &diff_opts);
 945                        diffcore_std(&diff_opts);
 946                        diff_flush(&diff_opts);
 947                        parent = parent->next;
 948                }
 949        }
 950
 951        argv_array_clear(&argv);
 952        sha1_array_clear(&ref_tips_before_fetch);
 953        sha1_array_clear(&ref_tips_after_fetch);
 954        initialized_fetch_ref_tips = 0;
 955}
 956
 957struct submodule_parallel_fetch {
 958        int count;
 959        struct argv_array args;
 960        const char *work_tree;
 961        const char *prefix;
 962        int command_line_option;
 963        int quiet;
 964        int result;
 965};
 966#define SPF_INIT {0, ARGV_ARRAY_INIT, NULL, NULL, 0, 0, 0}
 967
 968static int get_next_submodule(struct child_process *cp,
 969                              struct strbuf *err, void *data, void **task_cb)
 970{
 971        int ret = 0;
 972        struct submodule_parallel_fetch *spf = data;
 973
 974        for (; spf->count < active_nr; spf->count++) {
 975                struct strbuf submodule_path = STRBUF_INIT;
 976                struct strbuf submodule_git_dir = STRBUF_INIT;
 977                struct strbuf submodule_prefix = STRBUF_INIT;
 978                const struct cache_entry *ce = active_cache[spf->count];
 979                const char *git_dir, *default_argv;
 980                const struct submodule *submodule;
 981
 982                if (!S_ISGITLINK(ce->ce_mode))
 983                        continue;
 984
 985                submodule = submodule_from_path(null_sha1, ce->name);
 986                if (!submodule)
 987                        submodule = submodule_from_name(null_sha1, ce->name);
 988
 989                default_argv = "yes";
 990                if (spf->command_line_option == RECURSE_SUBMODULES_DEFAULT) {
 991                        if (submodule &&
 992                            submodule->fetch_recurse !=
 993                                                RECURSE_SUBMODULES_NONE) {
 994                                if (submodule->fetch_recurse ==
 995                                                RECURSE_SUBMODULES_OFF)
 996                                        continue;
 997                                if (submodule->fetch_recurse ==
 998                                                RECURSE_SUBMODULES_ON_DEMAND) {
 999                                        if (!unsorted_string_list_lookup(&changed_submodule_paths, ce->name))
1000                                                continue;
1001                                        default_argv = "on-demand";
1002                                }
1003                        } else {
1004                                if ((config_fetch_recurse_submodules == RECURSE_SUBMODULES_OFF) ||
1005                                    gitmodules_is_unmerged)
1006                                        continue;
1007                                if (config_fetch_recurse_submodules == RECURSE_SUBMODULES_ON_DEMAND) {
1008                                        if (!unsorted_string_list_lookup(&changed_submodule_paths, ce->name))
1009                                                continue;
1010                                        default_argv = "on-demand";
1011                                }
1012                        }
1013                } else if (spf->command_line_option == RECURSE_SUBMODULES_ON_DEMAND) {
1014                        if (!unsorted_string_list_lookup(&changed_submodule_paths, ce->name))
1015                                continue;
1016                        default_argv = "on-demand";
1017                }
1018
1019                strbuf_addf(&submodule_path, "%s/%s", spf->work_tree, ce->name);
1020                strbuf_addf(&submodule_git_dir, "%s/.git", submodule_path.buf);
1021                strbuf_addf(&submodule_prefix, "%s%s/", spf->prefix, ce->name);
1022                git_dir = read_gitfile(submodule_git_dir.buf);
1023                if (!git_dir)
1024                        git_dir = submodule_git_dir.buf;
1025                if (is_directory(git_dir)) {
1026                        child_process_init(cp);
1027                        cp->dir = strbuf_detach(&submodule_path, NULL);
1028                        prepare_submodule_repo_env(&cp->env_array);
1029                        cp->git_cmd = 1;
1030                        if (!spf->quiet)
1031                                strbuf_addf(err, "Fetching submodule %s%s\n",
1032                                            spf->prefix, ce->name);
1033                        argv_array_init(&cp->args);
1034                        argv_array_pushv(&cp->args, spf->args.argv);
1035                        argv_array_push(&cp->args, default_argv);
1036                        argv_array_push(&cp->args, "--submodule-prefix");
1037                        argv_array_push(&cp->args, submodule_prefix.buf);
1038                        ret = 1;
1039                }
1040                strbuf_release(&submodule_path);
1041                strbuf_release(&submodule_git_dir);
1042                strbuf_release(&submodule_prefix);
1043                if (ret) {
1044                        spf->count++;
1045                        return 1;
1046                }
1047        }
1048        return 0;
1049}
1050
1051static int fetch_start_failure(struct strbuf *err,
1052                               void *cb, void *task_cb)
1053{
1054        struct submodule_parallel_fetch *spf = cb;
1055
1056        spf->result = 1;
1057
1058        return 0;
1059}
1060
1061static int fetch_finish(int retvalue, struct strbuf *err,
1062                        void *cb, void *task_cb)
1063{
1064        struct submodule_parallel_fetch *spf = cb;
1065
1066        if (retvalue)
1067                spf->result = 1;
1068
1069        return 0;
1070}
1071
1072int fetch_populated_submodules(const struct argv_array *options,
1073                               const char *prefix, int command_line_option,
1074                               int quiet, int max_parallel_jobs)
1075{
1076        int i;
1077        struct submodule_parallel_fetch spf = SPF_INIT;
1078
1079        spf.work_tree = get_git_work_tree();
1080        spf.command_line_option = command_line_option;
1081        spf.quiet = quiet;
1082        spf.prefix = prefix;
1083
1084        if (!spf.work_tree)
1085                goto out;
1086
1087        if (read_cache() < 0)
1088                die("index file corrupt");
1089
1090        argv_array_push(&spf.args, "fetch");
1091        for (i = 0; i < options->argc; i++)
1092                argv_array_push(&spf.args, options->argv[i]);
1093        argv_array_push(&spf.args, "--recurse-submodules-default");
1094        /* default value, "--submodule-prefix" and its value are added later */
1095
1096        if (max_parallel_jobs < 0)
1097                max_parallel_jobs = parallel_jobs;
1098
1099        calculate_changed_submodule_paths();
1100        run_processes_parallel(max_parallel_jobs,
1101                               get_next_submodule,
1102                               fetch_start_failure,
1103                               fetch_finish,
1104                               &spf);
1105
1106        argv_array_clear(&spf.args);
1107out:
1108        string_list_clear(&changed_submodule_paths, 1);
1109        return spf.result;
1110}
1111
1112unsigned is_submodule_modified(const char *path, int ignore_untracked)
1113{
1114        ssize_t len;
1115        struct child_process cp = CHILD_PROCESS_INIT;
1116        const char *argv[] = {
1117                "status",
1118                "--porcelain",
1119                NULL,
1120                NULL,
1121        };
1122        struct strbuf buf = STRBUF_INIT;
1123        unsigned dirty_submodule = 0;
1124        const char *line, *next_line;
1125        const char *git_dir;
1126
1127        strbuf_addf(&buf, "%s/.git", path);
1128        git_dir = read_gitfile(buf.buf);
1129        if (!git_dir)
1130                git_dir = buf.buf;
1131        if (!is_directory(git_dir)) {
1132                strbuf_release(&buf);
1133                /* The submodule is not checked out, so it is not modified */
1134                return 0;
1135
1136        }
1137        strbuf_reset(&buf);
1138
1139        if (ignore_untracked)
1140                argv[2] = "-uno";
1141
1142        cp.argv = argv;
1143        prepare_submodule_repo_env(&cp.env_array);
1144        cp.git_cmd = 1;
1145        cp.no_stdin = 1;
1146        cp.out = -1;
1147        cp.dir = path;
1148        if (start_command(&cp))
1149                die("Could not run 'git status --porcelain' in submodule %s", path);
1150
1151        len = strbuf_read(&buf, cp.out, 1024);
1152        line = buf.buf;
1153        while (len > 2) {
1154                if ((line[0] == '?') && (line[1] == '?')) {
1155                        dirty_submodule |= DIRTY_SUBMODULE_UNTRACKED;
1156                        if (dirty_submodule & DIRTY_SUBMODULE_MODIFIED)
1157                                break;
1158                } else {
1159                        dirty_submodule |= DIRTY_SUBMODULE_MODIFIED;
1160                        if (ignore_untracked ||
1161                            (dirty_submodule & DIRTY_SUBMODULE_UNTRACKED))
1162                                break;
1163                }
1164                next_line = strchr(line, '\n');
1165                if (!next_line)
1166                        break;
1167                next_line++;
1168                len -= (next_line - line);
1169                line = next_line;
1170        }
1171        close(cp.out);
1172
1173        if (finish_command(&cp))
1174                die("'git status --porcelain' failed in submodule %s", path);
1175
1176        strbuf_release(&buf);
1177        return dirty_submodule;
1178}
1179
1180int submodule_uses_gitfile(const char *path)
1181{
1182        struct child_process cp = CHILD_PROCESS_INIT;
1183        const char *argv[] = {
1184                "submodule",
1185                "foreach",
1186                "--quiet",
1187                "--recursive",
1188                "test -f .git",
1189                NULL,
1190        };
1191        struct strbuf buf = STRBUF_INIT;
1192        const char *git_dir;
1193
1194        strbuf_addf(&buf, "%s/.git", path);
1195        git_dir = read_gitfile(buf.buf);
1196        if (!git_dir) {
1197                strbuf_release(&buf);
1198                return 0;
1199        }
1200        strbuf_release(&buf);
1201
1202        /* Now test that all nested submodules use a gitfile too */
1203        cp.argv = argv;
1204        prepare_submodule_repo_env(&cp.env_array);
1205        cp.git_cmd = 1;
1206        cp.no_stdin = 1;
1207        cp.no_stderr = 1;
1208        cp.no_stdout = 1;
1209        cp.dir = path;
1210        if (run_command(&cp))
1211                return 0;
1212
1213        return 1;
1214}
1215
1216/*
1217 * Check if it is a bad idea to remove a submodule, i.e. if we'd lose data
1218 * when doing so.
1219 *
1220 * Return 1 if we'd lose data, return 0 if the removal is fine,
1221 * and negative values for errors.
1222 */
1223int bad_to_remove_submodule(const char *path, unsigned flags)
1224{
1225        ssize_t len;
1226        struct child_process cp = CHILD_PROCESS_INIT;
1227        struct strbuf buf = STRBUF_INIT;
1228        int ret = 0;
1229
1230        if (!file_exists(path) || is_empty_dir(path))
1231                return 0;
1232
1233        if (!submodule_uses_gitfile(path))
1234                return 1;
1235
1236        argv_array_pushl(&cp.args, "status", "--porcelain",
1237                                   "--ignore-submodules=none", NULL);
1238
1239        if (flags & SUBMODULE_REMOVAL_IGNORE_UNTRACKED)
1240                argv_array_push(&cp.args, "-uno");
1241        else
1242                argv_array_push(&cp.args, "-uall");
1243
1244        if (!(flags & SUBMODULE_REMOVAL_IGNORE_IGNORED_UNTRACKED))
1245                argv_array_push(&cp.args, "--ignored");
1246
1247        prepare_submodule_repo_env(&cp.env_array);
1248        cp.git_cmd = 1;
1249        cp.no_stdin = 1;
1250        cp.out = -1;
1251        cp.dir = path;
1252        if (start_command(&cp)) {
1253                if (flags & SUBMODULE_REMOVAL_DIE_ON_ERROR)
1254                        die(_("could not start 'git status in submodule '%s'"),
1255                                path);
1256                ret = -1;
1257                goto out;
1258        }
1259
1260        len = strbuf_read(&buf, cp.out, 1024);
1261        if (len > 2)
1262                ret = 1;
1263        close(cp.out);
1264
1265        if (finish_command(&cp)) {
1266                if (flags & SUBMODULE_REMOVAL_DIE_ON_ERROR)
1267                        die(_("could not run 'git status in submodule '%s'"),
1268                                path);
1269                ret = -1;
1270        }
1271out:
1272        strbuf_release(&buf);
1273        return ret;
1274}
1275
1276static const char *get_super_prefix_or_empty(void)
1277{
1278        const char *s = get_super_prefix();
1279        if (!s)
1280                s = "";
1281        return s;
1282}
1283
1284static int submodule_has_dirty_index(const struct submodule *sub)
1285{
1286        struct child_process cp = CHILD_PROCESS_INIT;
1287
1288        prepare_submodule_repo_env_no_git_dir(&cp.env_array);
1289
1290        cp.git_cmd = 1;
1291        argv_array_pushl(&cp.args, "diff-index", "--quiet",
1292                                   "--cached", "HEAD", NULL);
1293        cp.no_stdin = 1;
1294        cp.no_stdout = 1;
1295        cp.dir = sub->path;
1296        if (start_command(&cp))
1297                die("could not recurse into submodule '%s'", sub->path);
1298
1299        return finish_command(&cp);
1300}
1301
1302static void submodule_reset_index(const char *path)
1303{
1304        struct child_process cp = CHILD_PROCESS_INIT;
1305        prepare_submodule_repo_env_no_git_dir(&cp.env_array);
1306
1307        cp.git_cmd = 1;
1308        cp.no_stdin = 1;
1309        cp.dir = path;
1310
1311        argv_array_pushf(&cp.args, "--super-prefix=%s%s/",
1312                                   get_super_prefix_or_empty(), path);
1313        argv_array_pushl(&cp.args, "read-tree", "-u", "--reset", NULL);
1314
1315        argv_array_push(&cp.args, EMPTY_TREE_SHA1_HEX);
1316
1317        if (run_command(&cp))
1318                die("could not reset submodule index");
1319}
1320
1321/**
1322 * Moves a submodule at a given path from a given head to another new head.
1323 * For edge cases (a submodule coming into existence or removing a submodule)
1324 * pass NULL for old or new respectively.
1325 */
1326int submodule_move_head(const char *path,
1327                         const char *old,
1328                         const char *new,
1329                         unsigned flags)
1330{
1331        int ret = 0;
1332        struct child_process cp = CHILD_PROCESS_INIT;
1333        const struct submodule *sub;
1334
1335        sub = submodule_from_path(null_sha1, path);
1336
1337        if (!sub)
1338                die("BUG: could not get submodule information for '%s'", path);
1339
1340        if (old && !(flags & SUBMODULE_MOVE_HEAD_FORCE)) {
1341                /* Check if the submodule has a dirty index. */
1342                if (submodule_has_dirty_index(sub))
1343                        return error(_("submodule '%s' has dirty index"), path);
1344        }
1345
1346        if (!(flags & SUBMODULE_MOVE_HEAD_DRY_RUN)) {
1347                if (old) {
1348                        if (!submodule_uses_gitfile(path))
1349                                absorb_git_dir_into_superproject("", path,
1350                                        ABSORB_GITDIR_RECURSE_SUBMODULES);
1351                } else {
1352                        struct strbuf sb = STRBUF_INIT;
1353                        strbuf_addf(&sb, "%s/modules/%s",
1354                                    get_git_common_dir(), sub->name);
1355                        connect_work_tree_and_git_dir(path, sb.buf);
1356                        strbuf_release(&sb);
1357
1358                        /* make sure the index is clean as well */
1359                        submodule_reset_index(path);
1360                }
1361        }
1362
1363        prepare_submodule_repo_env_no_git_dir(&cp.env_array);
1364
1365        cp.git_cmd = 1;
1366        cp.no_stdin = 1;
1367        cp.dir = path;
1368
1369        argv_array_pushf(&cp.args, "--super-prefix=%s%s/",
1370                        get_super_prefix_or_empty(), path);
1371        argv_array_pushl(&cp.args, "read-tree", NULL);
1372
1373        if (flags & SUBMODULE_MOVE_HEAD_DRY_RUN)
1374                argv_array_push(&cp.args, "-n");
1375        else
1376                argv_array_push(&cp.args, "-u");
1377
1378        if (flags & SUBMODULE_MOVE_HEAD_FORCE)
1379                argv_array_push(&cp.args, "--reset");
1380        else
1381                argv_array_push(&cp.args, "-m");
1382
1383        argv_array_push(&cp.args, old ? old : EMPTY_TREE_SHA1_HEX);
1384        argv_array_push(&cp.args, new ? new : EMPTY_TREE_SHA1_HEX);
1385
1386        if (run_command(&cp)) {
1387                ret = -1;
1388                goto out;
1389        }
1390
1391        if (!(flags & SUBMODULE_MOVE_HEAD_DRY_RUN)) {
1392                if (new) {
1393                        struct child_process cp1 = CHILD_PROCESS_INIT;
1394                        /* also set the HEAD accordingly */
1395                        cp1.git_cmd = 1;
1396                        cp1.no_stdin = 1;
1397                        cp1.dir = path;
1398
1399                        argv_array_pushl(&cp1.args, "update-ref", "HEAD",
1400                                         new ? new : EMPTY_TREE_SHA1_HEX, NULL);
1401
1402                        if (run_command(&cp1)) {
1403                                ret = -1;
1404                                goto out;
1405                        }
1406                } else {
1407                        struct strbuf sb = STRBUF_INIT;
1408
1409                        strbuf_addf(&sb, "%s/.git", path);
1410                        unlink_or_warn(sb.buf);
1411                        strbuf_release(&sb);
1412
1413                        if (is_empty_dir(path))
1414                                rmdir_or_warn(path);
1415                }
1416        }
1417out:
1418        return ret;
1419}
1420
1421static int find_first_merges(struct object_array *result, const char *path,
1422                struct commit *a, struct commit *b)
1423{
1424        int i, j;
1425        struct object_array merges = OBJECT_ARRAY_INIT;
1426        struct commit *commit;
1427        int contains_another;
1428
1429        char merged_revision[42];
1430        const char *rev_args[] = { "rev-list", "--merges", "--ancestry-path",
1431                                   "--all", merged_revision, NULL };
1432        struct rev_info revs;
1433        struct setup_revision_opt rev_opts;
1434
1435        memset(result, 0, sizeof(struct object_array));
1436        memset(&rev_opts, 0, sizeof(rev_opts));
1437
1438        /* get all revisions that merge commit a */
1439        xsnprintf(merged_revision, sizeof(merged_revision), "^%s",
1440                        oid_to_hex(&a->object.oid));
1441        init_revisions(&revs, NULL);
1442        rev_opts.submodule = path;
1443        setup_revisions(ARRAY_SIZE(rev_args)-1, rev_args, &revs, &rev_opts);
1444
1445        /* save all revisions from the above list that contain b */
1446        if (prepare_revision_walk(&revs))
1447                die("revision walk setup failed");
1448        while ((commit = get_revision(&revs)) != NULL) {
1449                struct object *o = &(commit->object);
1450                if (in_merge_bases(b, commit))
1451                        add_object_array(o, NULL, &merges);
1452        }
1453        reset_revision_walk();
1454
1455        /* Now we've got all merges that contain a and b. Prune all
1456         * merges that contain another found merge and save them in
1457         * result.
1458         */
1459        for (i = 0; i < merges.nr; i++) {
1460                struct commit *m1 = (struct commit *) merges.objects[i].item;
1461
1462                contains_another = 0;
1463                for (j = 0; j < merges.nr; j++) {
1464                        struct commit *m2 = (struct commit *) merges.objects[j].item;
1465                        if (i != j && in_merge_bases(m2, m1)) {
1466                                contains_another = 1;
1467                                break;
1468                        }
1469                }
1470
1471                if (!contains_another)
1472                        add_object_array(merges.objects[i].item, NULL, result);
1473        }
1474
1475        free(merges.objects);
1476        return result->nr;
1477}
1478
1479static void print_commit(struct commit *commit)
1480{
1481        struct strbuf sb = STRBUF_INIT;
1482        struct pretty_print_context ctx = {0};
1483        ctx.date_mode.type = DATE_NORMAL;
1484        format_commit_message(commit, " %h: %m %s", &sb, &ctx);
1485        fprintf(stderr, "%s\n", sb.buf);
1486        strbuf_release(&sb);
1487}
1488
1489#define MERGE_WARNING(path, msg) \
1490        warning("Failed to merge submodule %s (%s)", path, msg);
1491
1492int merge_submodule(unsigned char result[20], const char *path,
1493                    const unsigned char base[20], const unsigned char a[20],
1494                    const unsigned char b[20], int search)
1495{
1496        struct commit *commit_base, *commit_a, *commit_b;
1497        int parent_count;
1498        struct object_array merges;
1499
1500        int i;
1501
1502        /* store a in result in case we fail */
1503        hashcpy(result, a);
1504
1505        /* we can not handle deletion conflicts */
1506        if (is_null_sha1(base))
1507                return 0;
1508        if (is_null_sha1(a))
1509                return 0;
1510        if (is_null_sha1(b))
1511                return 0;
1512
1513        if (add_submodule_odb(path)) {
1514                MERGE_WARNING(path, "not checked out");
1515                return 0;
1516        }
1517
1518        if (!(commit_base = lookup_commit_reference(base)) ||
1519            !(commit_a = lookup_commit_reference(a)) ||
1520            !(commit_b = lookup_commit_reference(b))) {
1521                MERGE_WARNING(path, "commits not present");
1522                return 0;
1523        }
1524
1525        /* check whether both changes are forward */
1526        if (!in_merge_bases(commit_base, commit_a) ||
1527            !in_merge_bases(commit_base, commit_b)) {
1528                MERGE_WARNING(path, "commits don't follow merge-base");
1529                return 0;
1530        }
1531
1532        /* Case #1: a is contained in b or vice versa */
1533        if (in_merge_bases(commit_a, commit_b)) {
1534                hashcpy(result, b);
1535                return 1;
1536        }
1537        if (in_merge_bases(commit_b, commit_a)) {
1538                hashcpy(result, a);
1539                return 1;
1540        }
1541
1542        /*
1543         * Case #2: There are one or more merges that contain a and b in
1544         * the submodule. If there is only one, then present it as a
1545         * suggestion to the user, but leave it marked unmerged so the
1546         * user needs to confirm the resolution.
1547         */
1548
1549        /* Skip the search if makes no sense to the calling context.  */
1550        if (!search)
1551                return 0;
1552
1553        /* find commit which merges them */
1554        parent_count = find_first_merges(&merges, path, commit_a, commit_b);
1555        switch (parent_count) {
1556        case 0:
1557                MERGE_WARNING(path, "merge following commits not found");
1558                break;
1559
1560        case 1:
1561                MERGE_WARNING(path, "not fast-forward");
1562                fprintf(stderr, "Found a possible merge resolution "
1563                                "for the submodule:\n");
1564                print_commit((struct commit *) merges.objects[0].item);
1565                fprintf(stderr,
1566                        "If this is correct simply add it to the index "
1567                        "for example\n"
1568                        "by using:\n\n"
1569                        "  git update-index --cacheinfo 160000 %s \"%s\"\n\n"
1570                        "which will accept this suggestion.\n",
1571                        oid_to_hex(&merges.objects[0].item->oid), path);
1572                break;
1573
1574        default:
1575                MERGE_WARNING(path, "multiple merges found");
1576                for (i = 0; i < merges.nr; i++)
1577                        print_commit((struct commit *) merges.objects[i].item);
1578        }
1579
1580        free(merges.objects);
1581        return 0;
1582}
1583
1584int parallel_submodules(void)
1585{
1586        return parallel_jobs;
1587}
1588
1589/*
1590 * Embeds a single submodules git directory into the superprojects git dir,
1591 * non recursively.
1592 */
1593static void relocate_single_git_dir_into_superproject(const char *prefix,
1594                                                      const char *path)
1595{
1596        char *old_git_dir = NULL, *real_old_git_dir = NULL, *real_new_git_dir = NULL;
1597        const char *new_git_dir;
1598        const struct submodule *sub;
1599
1600        if (submodule_uses_worktrees(path))
1601                die(_("relocate_gitdir for submodule '%s' with "
1602                      "more than one worktree not supported"), path);
1603
1604        old_git_dir = xstrfmt("%s/.git", path);
1605        if (read_gitfile(old_git_dir))
1606                /* If it is an actual gitfile, it doesn't need migration. */
1607                return;
1608
1609        real_old_git_dir = real_pathdup(old_git_dir, 1);
1610
1611        sub = submodule_from_path(null_sha1, path);
1612        if (!sub)
1613                die(_("could not lookup name for submodule '%s'"), path);
1614
1615        new_git_dir = git_path("modules/%s", sub->name);
1616        if (safe_create_leading_directories_const(new_git_dir) < 0)
1617                die(_("could not create directory '%s'"), new_git_dir);
1618        real_new_git_dir = real_pathdup(new_git_dir, 1);
1619
1620        fprintf(stderr, _("Migrating git directory of '%s%s' from\n'%s' to\n'%s'\n"),
1621                get_super_prefix_or_empty(), path,
1622                real_old_git_dir, real_new_git_dir);
1623
1624        relocate_gitdir(path, real_old_git_dir, real_new_git_dir);
1625
1626        free(old_git_dir);
1627        free(real_old_git_dir);
1628        free(real_new_git_dir);
1629}
1630
1631/*
1632 * Migrate the git directory of the submodule given by path from
1633 * having its git directory within the working tree to the git dir nested
1634 * in its superprojects git dir under modules/.
1635 */
1636void absorb_git_dir_into_superproject(const char *prefix,
1637                                      const char *path,
1638                                      unsigned flags)
1639{
1640        int err_code;
1641        const char *sub_git_dir;
1642        struct strbuf gitdir = STRBUF_INIT;
1643        strbuf_addf(&gitdir, "%s/.git", path);
1644        sub_git_dir = resolve_gitdir_gently(gitdir.buf, &err_code);
1645
1646        /* Not populated? */
1647        if (!sub_git_dir) {
1648                const struct submodule *sub;
1649
1650                if (err_code == READ_GITFILE_ERR_STAT_FAILED) {
1651                        /* unpopulated as expected */
1652                        strbuf_release(&gitdir);
1653                        return;
1654                }
1655
1656                if (err_code != READ_GITFILE_ERR_NOT_A_REPO)
1657                        /* We don't know what broke here. */
1658                        read_gitfile_error_die(err_code, path, NULL);
1659
1660                /*
1661                * Maybe populated, but no git directory was found?
1662                * This can happen if the superproject is a submodule
1663                * itself and was just absorbed. The absorption of the
1664                * superproject did not rewrite the git file links yet,
1665                * fix it now.
1666                */
1667                sub = submodule_from_path(null_sha1, path);
1668                if (!sub)
1669                        die(_("could not lookup name for submodule '%s'"), path);
1670                connect_work_tree_and_git_dir(path,
1671                        git_path("modules/%s", sub->name));
1672        } else {
1673                /* Is it already absorbed into the superprojects git dir? */
1674                char *real_sub_git_dir = real_pathdup(sub_git_dir, 1);
1675                char *real_common_git_dir = real_pathdup(get_git_common_dir(), 1);
1676
1677                if (!starts_with(real_sub_git_dir, real_common_git_dir))
1678                        relocate_single_git_dir_into_superproject(prefix, path);
1679
1680                free(real_sub_git_dir);
1681                free(real_common_git_dir);
1682        }
1683        strbuf_release(&gitdir);
1684
1685        if (flags & ABSORB_GITDIR_RECURSE_SUBMODULES) {
1686                struct child_process cp = CHILD_PROCESS_INIT;
1687                struct strbuf sb = STRBUF_INIT;
1688
1689                if (flags & ~ABSORB_GITDIR_RECURSE_SUBMODULES)
1690                        die("BUG: we don't know how to pass the flags down?");
1691
1692                strbuf_addstr(&sb, get_super_prefix_or_empty());
1693                strbuf_addstr(&sb, path);
1694                strbuf_addch(&sb, '/');
1695
1696                cp.dir = path;
1697                cp.git_cmd = 1;
1698                cp.no_stdin = 1;
1699                argv_array_pushl(&cp.args, "--super-prefix", sb.buf,
1700                                           "submodule--helper",
1701                                           "absorb-git-dirs", NULL);
1702                prepare_submodule_repo_env(&cp.env_array);
1703                if (run_command(&cp))
1704                        die(_("could not recurse into submodule '%s'"), path);
1705
1706                strbuf_release(&sb);
1707        }
1708}
1709
1710const char *get_superproject_working_tree(void)
1711{
1712        struct child_process cp = CHILD_PROCESS_INIT;
1713        struct strbuf sb = STRBUF_INIT;
1714        const char *one_up = real_path_if_valid("../");
1715        const char *cwd = xgetcwd();
1716        const char *ret = NULL;
1717        const char *subpath;
1718        int code;
1719        ssize_t len;
1720
1721        if (!is_inside_work_tree())
1722                /*
1723                 * FIXME:
1724                 * We might have a superproject, but it is harder
1725                 * to determine.
1726                 */
1727                return NULL;
1728
1729        if (!one_up)
1730                return NULL;
1731
1732        subpath = relative_path(cwd, one_up, &sb);
1733
1734        prepare_submodule_repo_env(&cp.env_array);
1735        argv_array_pop(&cp.env_array);
1736
1737        argv_array_pushl(&cp.args, "--literal-pathspecs", "-C", "..",
1738                        "ls-files", "-z", "--stage", "--full-name", "--",
1739                        subpath, NULL);
1740        strbuf_reset(&sb);
1741
1742        cp.no_stdin = 1;
1743        cp.no_stderr = 1;
1744        cp.out = -1;
1745        cp.git_cmd = 1;
1746
1747        if (start_command(&cp))
1748                die(_("could not start ls-files in .."));
1749
1750        len = strbuf_read(&sb, cp.out, PATH_MAX);
1751        close(cp.out);
1752
1753        if (starts_with(sb.buf, "160000")) {
1754                int super_sub_len;
1755                int cwd_len = strlen(cwd);
1756                char *super_sub, *super_wt;
1757
1758                /*
1759                 * There is a superproject having this repo as a submodule.
1760                 * The format is <mode> SP <hash> SP <stage> TAB <full name> \0,
1761                 * We're only interested in the name after the tab.
1762                 */
1763                super_sub = strchr(sb.buf, '\t') + 1;
1764                super_sub_len = sb.buf + sb.len - super_sub - 1;
1765
1766                if (super_sub_len > cwd_len ||
1767                    strcmp(&cwd[cwd_len - super_sub_len], super_sub))
1768                        die (_("BUG: returned path string doesn't match cwd?"));
1769
1770                super_wt = xstrdup(cwd);
1771                super_wt[cwd_len - super_sub_len] = '\0';
1772
1773                ret = real_path(super_wt);
1774                free(super_wt);
1775        }
1776        strbuf_release(&sb);
1777
1778        code = finish_command(&cp);
1779
1780        if (code == 128)
1781                /* '../' is not a git repository */
1782                return NULL;
1783        if (code == 0 && len == 0)
1784                /* There is an unrelated git repository at '../' */
1785                return NULL;
1786        if (code)
1787                die(_("ls-tree returned unexpected return code %d"), code);
1788
1789        return ret;
1790}