diff options
Diffstat (limited to 'submodule.c')
| -rw-r--r-- | submodule.c | 881 |
1 files changed, 881 insertions, 0 deletions
diff --git a/submodule.c b/submodule.c new file mode 100644 index 0000000000..0b709bc291 --- /dev/null +++ b/submodule.c @@ -0,0 +1,881 @@ +#include "cache.h" +#include "submodule.h" +#include "dir.h" +#include "diff.h" +#include "commit.h" +#include "revision.h" +#include "run-command.h" +#include "diffcore.h" +#include "refs.h" +#include "string-list.h" +#include "sha1-array.h" +#include "argv-array.h" + +static struct string_list config_name_for_path; +static struct string_list config_fetch_recurse_submodules_for_name; +static struct string_list config_ignore_for_name; +static int config_fetch_recurse_submodules = RECURSE_SUBMODULES_ON_DEMAND; +static struct string_list changed_submodule_paths; +static int initialized_fetch_ref_tips; +static struct sha1_array ref_tips_before_fetch; +static struct sha1_array ref_tips_after_fetch; + +/* + * The following flag is set if the .gitmodules file is unmerged. We then + * disable recursion for all submodules where .git/config doesn't have a + * matching config entry because we can't guess what might be configured in + * .gitmodules unless the user resolves the conflict. When a command line + * option is given (which always overrides configuration) this flag will be + * ignored. + */ +static int gitmodules_is_unmerged; + +static int add_submodule_odb(const char *path) +{ + struct strbuf objects_directory = STRBUF_INIT; + struct alternate_object_database *alt_odb; + int ret = 0; + const char *git_dir; + + strbuf_addf(&objects_directory, "%s/.git", path); + git_dir = read_gitfile(objects_directory.buf); + if (git_dir) { + strbuf_reset(&objects_directory); + strbuf_addstr(&objects_directory, git_dir); + } + strbuf_addstr(&objects_directory, "/objects/"); + if (!is_directory(objects_directory.buf)) { + ret = -1; + goto done; + } + /* avoid adding it twice */ + for (alt_odb = alt_odb_list; alt_odb; alt_odb = alt_odb->next) + if (alt_odb->name - alt_odb->base == objects_directory.len && + !strncmp(alt_odb->base, objects_directory.buf, + objects_directory.len)) + goto done; + + alt_odb = xmalloc(objects_directory.len + 42 + sizeof(*alt_odb)); + alt_odb->next = alt_odb_list; + strcpy(alt_odb->base, objects_directory.buf); + alt_odb->name = alt_odb->base + objects_directory.len; + alt_odb->name[2] = '/'; + alt_odb->name[40] = '\0'; + alt_odb->name[41] = '\0'; + alt_odb_list = alt_odb; + prepare_alt_odb(); +done: + strbuf_release(&objects_directory); + return ret; +} + +void set_diffopt_flags_from_submodule_config(struct diff_options *diffopt, + const char *path) +{ + struct string_list_item *path_option, *ignore_option; + path_option = unsorted_string_list_lookup(&config_name_for_path, path); + if (path_option) { + ignore_option = unsorted_string_list_lookup(&config_ignore_for_name, path_option->util); + if (ignore_option) + handle_ignore_submodules_arg(diffopt, ignore_option->util); + else if (gitmodules_is_unmerged) + DIFF_OPT_SET(diffopt, IGNORE_SUBMODULES); + } +} + +int submodule_config(const char *var, const char *value, void *cb) +{ + if (!prefixcmp(var, "submodule.")) + return parse_submodule_config_option(var, value); + else if (!strcmp(var, "fetch.recursesubmodules")) { + config_fetch_recurse_submodules = parse_fetch_recurse_submodules_arg(var, value); + return 0; + } + return 0; +} + +void gitmodules_config(void) +{ + const char *work_tree = get_git_work_tree(); + if (work_tree) { + struct strbuf gitmodules_path = STRBUF_INIT; + int pos; + strbuf_addstr(&gitmodules_path, work_tree); + strbuf_addstr(&gitmodules_path, "/.gitmodules"); + if (read_cache() < 0) + die("index file corrupt"); + pos = cache_name_pos(".gitmodules", 11); + if (pos < 0) { /* .gitmodules not found or isn't merged */ + pos = -1 - pos; + if (active_nr > pos) { /* there is a .gitmodules */ + const struct cache_entry *ce = active_cache[pos]; + if (ce_namelen(ce) == 11 && + !memcmp(ce->name, ".gitmodules", 11)) + gitmodules_is_unmerged = 1; + } + } + + if (!gitmodules_is_unmerged) + git_config_from_file(submodule_config, gitmodules_path.buf, NULL); + strbuf_release(&gitmodules_path); + } +} + +int parse_submodule_config_option(const char *var, const char *value) +{ + int len; + struct string_list_item *config; + struct strbuf submodname = STRBUF_INIT; + + var += 10; /* Skip "submodule." */ + + len = strlen(var); + if ((len > 5) && !strcmp(var + len - 5, ".path")) { + strbuf_add(&submodname, var, len - 5); + config = unsorted_string_list_lookup(&config_name_for_path, value); + if (config) + free(config->util); + else + config = string_list_append(&config_name_for_path, xstrdup(value)); + config->util = strbuf_detach(&submodname, NULL); + strbuf_release(&submodname); + } else if ((len > 23) && !strcmp(var + len - 23, ".fetchrecursesubmodules")) { + strbuf_add(&submodname, var, len - 23); + config = unsorted_string_list_lookup(&config_fetch_recurse_submodules_for_name, submodname.buf); + if (!config) + config = string_list_append(&config_fetch_recurse_submodules_for_name, + strbuf_detach(&submodname, NULL)); + config->util = (void *)(intptr_t)parse_fetch_recurse_submodules_arg(var, value); + strbuf_release(&submodname); + } else if ((len > 7) && !strcmp(var + len - 7, ".ignore")) { + if (strcmp(value, "untracked") && strcmp(value, "dirty") && + strcmp(value, "all") && strcmp(value, "none")) { + warning("Invalid parameter \"%s\" for config option \"submodule.%s.ignore\"", value, var); + return 0; + } + + strbuf_add(&submodname, var, len - 7); + config = unsorted_string_list_lookup(&config_ignore_for_name, submodname.buf); + if (config) + free(config->util); + else + config = string_list_append(&config_ignore_for_name, + strbuf_detach(&submodname, NULL)); + strbuf_release(&submodname); + config->util = xstrdup(value); + return 0; + } + return 0; +} + +void handle_ignore_submodules_arg(struct diff_options *diffopt, + const char *arg) +{ + DIFF_OPT_CLR(diffopt, IGNORE_SUBMODULES); + DIFF_OPT_CLR(diffopt, IGNORE_UNTRACKED_IN_SUBMODULES); + DIFF_OPT_CLR(diffopt, IGNORE_DIRTY_SUBMODULES); + + if (!strcmp(arg, "all")) + DIFF_OPT_SET(diffopt, IGNORE_SUBMODULES); + else if (!strcmp(arg, "untracked")) + DIFF_OPT_SET(diffopt, IGNORE_UNTRACKED_IN_SUBMODULES); + else if (!strcmp(arg, "dirty")) + DIFF_OPT_SET(diffopt, IGNORE_DIRTY_SUBMODULES); + else if (strcmp(arg, "none")) + die("bad --ignore-submodules argument: %s", arg); +} + +static int prepare_submodule_summary(struct rev_info *rev, const char *path, + struct commit *left, struct commit *right, + int *fast_forward, int *fast_backward) +{ + struct commit_list *merge_bases, *list; + + init_revisions(rev, NULL); + setup_revisions(0, NULL, rev, NULL); + rev->left_right = 1; + rev->first_parent_only = 1; + left->object.flags |= SYMMETRIC_LEFT; + add_pending_object(rev, &left->object, path); + add_pending_object(rev, &right->object, path); + merge_bases = get_merge_bases(left, right, 1); + if (merge_bases) { + if (merge_bases->item == left) + *fast_forward = 1; + else if (merge_bases->item == right) + *fast_backward = 1; + } + for (list = merge_bases; list; list = list->next) { + list->item->object.flags |= UNINTERESTING; + add_pending_object(rev, &list->item->object, + sha1_to_hex(list->item->object.sha1)); + } + return prepare_revision_walk(rev); +} + +static void print_submodule_summary(struct rev_info *rev, FILE *f, + const char *del, const char *add, const char *reset) +{ + static const char format[] = " %m %s"; + struct strbuf sb = STRBUF_INIT; + struct commit *commit; + + while ((commit = get_revision(rev))) { + struct pretty_print_context ctx = {0}; + ctx.date_mode = rev->date_mode; + strbuf_setlen(&sb, 0); + if (commit->object.flags & SYMMETRIC_LEFT) { + if (del) + strbuf_addstr(&sb, del); + } + else if (add) + strbuf_addstr(&sb, add); + format_commit_message(commit, format, &sb, &ctx); + if (reset) + strbuf_addstr(&sb, reset); + strbuf_addch(&sb, '\n'); + fprintf(f, "%s", sb.buf); + } + strbuf_release(&sb); +} + +int parse_fetch_recurse_submodules_arg(const char *opt, const char *arg) +{ + switch (git_config_maybe_bool(opt, arg)) { + case 1: + return RECURSE_SUBMODULES_ON; + case 0: + return RECURSE_SUBMODULES_OFF; + default: + if (!strcmp(arg, "on-demand")) + return RECURSE_SUBMODULES_ON_DEMAND; + die("bad %s argument: %s", opt, arg); + } +} + +void show_submodule_summary(FILE *f, const char *path, + unsigned char one[20], unsigned char two[20], + unsigned dirty_submodule, + const char *del, const char *add, const char *reset) +{ + struct rev_info rev; + struct commit *left = left, *right = right; + const char *message = NULL; + struct strbuf sb = STRBUF_INIT; + int fast_forward = 0, fast_backward = 0; + + if (is_null_sha1(two)) + message = "(submodule deleted)"; + else if (add_submodule_odb(path)) + message = "(not checked out)"; + else if (is_null_sha1(one)) + message = "(new submodule)"; + else if (!(left = lookup_commit_reference(one)) || + !(right = lookup_commit_reference(two))) + message = "(commits not present)"; + + if (!message && + prepare_submodule_summary(&rev, path, left, right, + &fast_forward, &fast_backward)) + message = "(revision walker failed)"; + + if (dirty_submodule & DIRTY_SUBMODULE_UNTRACKED) + fprintf(f, "Submodule %s contains untracked content\n", path); + if (dirty_submodule & DIRTY_SUBMODULE_MODIFIED) + fprintf(f, "Submodule %s contains modified content\n", path); + + if (!hashcmp(one, two)) { + strbuf_release(&sb); + return; + } + + strbuf_addf(&sb, "Submodule %s %s..", path, + find_unique_abbrev(one, DEFAULT_ABBREV)); + if (!fast_backward && !fast_forward) + strbuf_addch(&sb, '.'); + strbuf_addf(&sb, "%s", find_unique_abbrev(two, DEFAULT_ABBREV)); + if (message) + strbuf_addf(&sb, " %s\n", message); + else + strbuf_addf(&sb, "%s:\n", fast_backward ? " (rewind)" : ""); + fwrite(sb.buf, sb.len, 1, f); + + if (!message) { + print_submodule_summary(&rev, f, del, add, reset); + clear_commit_marks(left, ~0); + clear_commit_marks(right, ~0); + } + + strbuf_release(&sb); +} + +void set_config_fetch_recurse_submodules(int value) +{ + config_fetch_recurse_submodules = value; +} + +static int has_remote(const char *refname, const unsigned char *sha1, int flags, void *cb_data) +{ + return 1; +} + +static int submodule_needs_pushing(const char *path, const unsigned char sha1[20]) +{ + if (add_submodule_odb(path) || !lookup_commit_reference(sha1)) + return 0; + + if (for_each_remote_ref_submodule(path, has_remote, NULL) > 0) { + struct child_process cp; + const char *argv[] = {"rev-list", NULL, "--not", "--remotes", "-n", "1" , NULL}; + struct strbuf buf = STRBUF_INIT; + int needs_pushing = 0; + + argv[1] = sha1_to_hex(sha1); + memset(&cp, 0, sizeof(cp)); + cp.argv = argv; + cp.env = local_repo_env; + cp.git_cmd = 1; + cp.no_stdin = 1; + cp.out = -1; + cp.dir = path; + if (start_command(&cp)) + die("Could not run 'git rev-list %s --not --remotes -n 1' command in submodule %s", + sha1_to_hex(sha1), path); + if (strbuf_read(&buf, cp.out, 41)) + needs_pushing = 1; + finish_command(&cp); + close(cp.out); + strbuf_release(&buf); + return needs_pushing; + } + + return 0; +} + +static void collect_submodules_from_diff(struct diff_queue_struct *q, + struct diff_options *options, + void *data) +{ + int i; + int *needs_pushing = data; + + for (i = 0; i < q->nr; i++) { + struct diff_filepair *p = q->queue[i]; + if (!S_ISGITLINK(p->two->mode)) + continue; + if (submodule_needs_pushing(p->two->path, p->two->sha1)) { + *needs_pushing = 1; + break; + } + } +} + + +static void commit_need_pushing(struct commit *commit, struct commit_list *parent, int *needs_pushing) +{ + const unsigned char (*parents)[20]; + unsigned int i, n; + struct rev_info rev; + + n = commit_list_count(parent); + parents = xmalloc(n * sizeof(*parents)); + + for (i = 0; i < n; i++) { + hashcpy((unsigned char *)(parents + i), parent->item->object.sha1); + parent = parent->next; + } + + init_revisions(&rev, NULL); + rev.diffopt.output_format |= DIFF_FORMAT_CALLBACK; + rev.diffopt.format_callback = collect_submodules_from_diff; + rev.diffopt.format_callback_data = needs_pushing; + diff_tree_combined(commit->object.sha1, parents, n, 1, &rev); + + free(parents); +} + +int check_submodule_needs_pushing(unsigned char new_sha1[20], const char *remotes_name) +{ + struct rev_info rev; + struct commit *commit; + const char *argv[] = {NULL, NULL, "--not", "NULL", NULL}; + int argc = ARRAY_SIZE(argv) - 1; + char *sha1_copy; + int needs_pushing = 0; + struct strbuf remotes_arg = STRBUF_INIT; + + strbuf_addf(&remotes_arg, "--remotes=%s", remotes_name); + init_revisions(&rev, NULL); + sha1_copy = xstrdup(sha1_to_hex(new_sha1)); + argv[1] = sha1_copy; + argv[3] = remotes_arg.buf; + setup_revisions(argc, argv, &rev, NULL); + if (prepare_revision_walk(&rev)) + die("revision walk setup failed"); + + while ((commit = get_revision(&rev)) && !needs_pushing) + commit_need_pushing(commit, commit->parents, &needs_pushing); + + free(sha1_copy); + strbuf_release(&remotes_arg); + + return needs_pushing; +} + +static int is_submodule_commit_present(const char *path, unsigned char sha1[20]) +{ + int is_present = 0; + if (!add_submodule_odb(path) && lookup_commit_reference(sha1)) { + /* Even if the submodule is checked out and the commit is + * present, make sure it is reachable from a ref. */ + struct child_process cp; + const char *argv[] = {"rev-list", "-n", "1", NULL, "--not", "--all", NULL}; + struct strbuf buf = STRBUF_INIT; + + argv[3] = sha1_to_hex(sha1); + memset(&cp, 0, sizeof(cp)); + cp.argv = argv; + cp.env = local_repo_env; + cp.git_cmd = 1; + cp.no_stdin = 1; + cp.out = -1; + cp.dir = path; + if (!run_command(&cp) && !strbuf_read(&buf, cp.out, 1024)) + is_present = 1; + + close(cp.out); + strbuf_release(&buf); + } + return is_present; +} + +static void submodule_collect_changed_cb(struct diff_queue_struct *q, + struct diff_options *options, + void *data) +{ + int i; + for (i = 0; i < q->nr; i++) { + struct diff_filepair *p = q->queue[i]; + if (!S_ISGITLINK(p->two->mode)) + continue; + + if (S_ISGITLINK(p->one->mode)) { + /* NEEDSWORK: We should honor the name configured in + * the .gitmodules file of the commit we are examining + * here to be able to correctly follow submodules + * being moved around. */ + struct string_list_item *path; + path = unsorted_string_list_lookup(&changed_submodule_paths, p->two->path); + if (!path && !is_submodule_commit_present(p->two->path, p->two->sha1)) + string_list_append(&changed_submodule_paths, xstrdup(p->two->path)); + } else { + /* Submodule is new or was moved here */ + /* NEEDSWORK: When the .git directories of submodules + * live inside the superprojects .git directory some + * day we should fetch new submodules directly into + * that location too when config or options request + * that so they can be checked out from there. */ + continue; + } + } +} + +static int add_sha1_to_array(const char *ref, const unsigned char *sha1, + int flags, void *data) +{ + sha1_array_append(data, sha1); + return 0; +} + +void check_for_new_submodule_commits(unsigned char new_sha1[20]) +{ + if (!initialized_fetch_ref_tips) { + for_each_ref(add_sha1_to_array, &ref_tips_before_fetch); + initialized_fetch_ref_tips = 1; + } + + sha1_array_append(&ref_tips_after_fetch, new_sha1); +} + +static void add_sha1_to_argv(const unsigned char sha1[20], void *data) +{ + argv_array_push(data, sha1_to_hex(sha1)); +} + +static void calculate_changed_submodule_paths(void) +{ + struct rev_info rev; + struct commit *commit; + struct argv_array argv = ARGV_ARRAY_INIT; + + /* No need to check if there are no submodules configured */ + if (!config_name_for_path.nr) + return; + + init_revisions(&rev, NULL); + argv_array_push(&argv, "--"); /* argv[0] program name */ + sha1_array_for_each_unique(&ref_tips_after_fetch, + add_sha1_to_argv, &argv); + argv_array_push(&argv, "--not"); + sha1_array_for_each_unique(&ref_tips_before_fetch, + add_sha1_to_argv, &argv); + setup_revisions(argv.argc, argv.argv, &rev, NULL); + if (prepare_revision_walk(&rev)) + die("revision walk setup failed"); + + /* + * Collect all submodules (whether checked out or not) for which new + * commits have been recorded upstream in "changed_submodule_paths". + */ + while ((commit = get_revision(&rev))) { + struct commit_list *parent = commit->parents; + while (parent) { + struct diff_options diff_opts; + diff_setup(&diff_opts); + DIFF_OPT_SET(&diff_opts, RECURSIVE); + diff_opts.output_format |= DIFF_FORMAT_CALLBACK; + diff_opts.format_callback = submodule_collect_changed_cb; + if (diff_setup_done(&diff_opts) < 0) + die("diff_setup_done failed"); + diff_tree_sha1(parent->item->object.sha1, commit->object.sha1, "", &diff_opts); + diffcore_std(&diff_opts); + diff_flush(&diff_opts); + parent = parent->next; + } + } + + argv_array_clear(&argv); + sha1_array_clear(&ref_tips_before_fetch); + sha1_array_clear(&ref_tips_after_fetch); + initialized_fetch_ref_tips = 0; +} + +int fetch_populated_submodules(int num_options, const char **options, + const char *prefix, int command_line_option, + int quiet) +{ + int i, result = 0, argc = 0, default_argc; + struct child_process cp; + const char **argv; + struct string_list_item *name_for_path; + const char *work_tree = get_git_work_tree(); + if (!work_tree) + goto out; + + if (!the_index.initialized) + if (read_cache() < 0) + die("index file corrupt"); + + /* 6: "fetch" (options) --recurse-submodules-default default "--submodule-prefix" prefix NULL */ + argv = xcalloc(num_options + 6, sizeof(const char *)); + argv[argc++] = "fetch"; + for (i = 0; i < num_options; i++) + argv[argc++] = options[i]; + argv[argc++] = "--recurse-submodules-default"; + default_argc = argc++; + argv[argc++] = "--submodule-prefix"; + + memset(&cp, 0, sizeof(cp)); + cp.argv = argv; + cp.env = local_repo_env; + cp.git_cmd = 1; + cp.no_stdin = 1; + + calculate_changed_submodule_paths(); + + for (i = 0; i < active_nr; i++) { + struct strbuf submodule_path = STRBUF_INIT; + struct strbuf submodule_git_dir = STRBUF_INIT; + struct strbuf submodule_prefix = STRBUF_INIT; + struct cache_entry *ce = active_cache[i]; + const char *git_dir, *name, *default_argv; + + if (!S_ISGITLINK(ce->ce_mode)) + continue; + + name = ce->name; + name_for_path = unsorted_string_list_lookup(&config_name_for_path, ce->name); + if (name_for_path) + name = name_for_path->util; + + default_argv = "yes"; + if (command_line_option == RECURSE_SUBMODULES_DEFAULT) { + struct string_list_item *fetch_recurse_submodules_option; + fetch_recurse_submodules_option = unsorted_string_list_lookup(&config_fetch_recurse_submodules_for_name, name); + if (fetch_recurse_submodules_option) { + if ((intptr_t)fetch_recurse_submodules_option->util == RECURSE_SUBMODULES_OFF) + continue; + if ((intptr_t)fetch_recurse_submodules_option->util == RECURSE_SUBMODULES_ON_DEMAND) { + if (!unsorted_string_list_lookup(&changed_submodule_paths, ce->name)) + continue; + default_argv = "on-demand"; + } + } else { + if ((config_fetch_recurse_submodules == RECURSE_SUBMODULES_OFF) || + gitmodules_is_unmerged) + continue; + if (config_fetch_recurse_submodules == RECURSE_SUBMODULES_ON_DEMAND) { + if (!unsorted_string_list_lookup(&changed_submodule_paths, ce->name)) + continue; + default_argv = "on-demand"; + } + } + } else if (command_line_option == RECURSE_SUBMODULES_ON_DEMAND) { + if (!unsorted_string_list_lookup(&changed_submodule_paths, ce->name)) + continue; + default_argv = "on-demand"; + } + + strbuf_addf(&submodule_path, "%s/%s", work_tree, ce->name); + strbuf_addf(&submodule_git_dir, "%s/.git", submodule_path.buf); + strbuf_addf(&submodule_prefix, "%s%s/", prefix, ce->name); + git_dir = read_gitfile(submodule_git_dir.buf); + if (!git_dir) + git_dir = submodule_git_dir.buf; + if (is_directory(git_dir)) { + if (!quiet) + printf("Fetching submodule %s%s\n", prefix, ce->name); + cp.dir = submodule_path.buf; + argv[default_argc] = default_argv; + argv[argc] = submodule_prefix.buf; + if (run_command(&cp)) + result = 1; + } + strbuf_release(&submodule_path); + strbuf_release(&submodule_git_dir); + strbuf_release(&submodule_prefix); + } + free(argv); +out: + string_list_clear(&changed_submodule_paths, 1); + return result; +} + +unsigned is_submodule_modified(const char *path, int ignore_untracked) +{ + ssize_t len; + struct child_process cp; + const char *argv[] = { + "status", + "--porcelain", + NULL, + NULL, + }; + struct strbuf buf = STRBUF_INIT; + unsigned dirty_submodule = 0; + const char *line, *next_line; + const char *git_dir; + + strbuf_addf(&buf, "%s/.git", path); + git_dir = read_gitfile(buf.buf); + if (!git_dir) + git_dir = buf.buf; + if (!is_directory(git_dir)) { + strbuf_release(&buf); + /* The submodule is not checked out, so it is not modified */ + return 0; + + } + strbuf_reset(&buf); + + if (ignore_untracked) + argv[2] = "-uno"; + + memset(&cp, 0, sizeof(cp)); + cp.argv = argv; + cp.env = local_repo_env; + cp.git_cmd = 1; + cp.no_stdin = 1; + cp.out = -1; + cp.dir = path; + if (start_command(&cp)) + die("Could not run git status --porcelain"); + + len = strbuf_read(&buf, cp.out, 1024); + line = buf.buf; + while (len > 2) { + if ((line[0] == '?') && (line[1] == '?')) { + dirty_submodule |= DIRTY_SUBMODULE_UNTRACKED; + if (dirty_submodule & DIRTY_SUBMODULE_MODIFIED) + break; + } else { + dirty_submodule |= DIRTY_SUBMODULE_MODIFIED; + if (ignore_untracked || + (dirty_submodule & DIRTY_SUBMODULE_UNTRACKED)) + break; + } + next_line = strchr(line, '\n'); + if (!next_line) + break; + next_line++; + len -= (next_line - line); + line = next_line; + } + close(cp.out); + + if (finish_command(&cp)) + die("git status --porcelain failed"); + + strbuf_release(&buf); + return dirty_submodule; +} + +static int find_first_merges(struct object_array *result, const char *path, + struct commit *a, struct commit *b) +{ + int i, j; + struct object_array merges; + struct commit *commit; + int contains_another; + + char merged_revision[42]; + const char *rev_args[] = { "rev-list", "--merges", "--ancestry-path", + "--all", merged_revision, NULL }; + struct rev_info revs; + struct setup_revision_opt rev_opts; + + memset(&merges, 0, sizeof(merges)); + memset(result, 0, sizeof(struct object_array)); + memset(&rev_opts, 0, sizeof(rev_opts)); + + /* get all revisions that merge commit a */ + snprintf(merged_revision, sizeof(merged_revision), "^%s", + sha1_to_hex(a->object.sha1)); + init_revisions(&revs, NULL); + rev_opts.submodule = path; + setup_revisions(sizeof(rev_args)/sizeof(char *)-1, rev_args, &revs, &rev_opts); + + /* save all revisions from the above list that contain b */ + if (prepare_revision_walk(&revs)) + die("revision walk setup failed"); + while ((commit = get_revision(&revs)) != NULL) { + struct object *o = &(commit->object); + if (in_merge_bases(b, &commit, 1)) + add_object_array(o, NULL, &merges); + } + + /* Now we've got all merges that contain a and b. Prune all + * merges that contain another found merge and save them in + * result. + */ + for (i = 0; i < merges.nr; i++) { + struct commit *m1 = (struct commit *) merges.objects[i].item; + + contains_another = 0; + for (j = 0; j < merges.nr; j++) { + struct commit *m2 = (struct commit *) merges.objects[j].item; + if (i != j && in_merge_bases(m2, &m1, 1)) { + contains_another = 1; + break; + } + } + + if (!contains_another) + add_object_array(merges.objects[i].item, + merges.objects[i].name, result); + } + + free(merges.objects); + return result->nr; +} + +static void print_commit(struct commit *commit) +{ + struct strbuf sb = STRBUF_INIT; + struct pretty_print_context ctx = {0}; + ctx.date_mode = DATE_NORMAL; + format_commit_message(commit, " %h: %m %s", &sb, &ctx); + fprintf(stderr, "%s\n", sb.buf); + strbuf_release(&sb); +} + +#define MERGE_WARNING(path, msg) \ + warning("Failed to merge submodule %s (%s)", path, msg); + +int merge_submodule(unsigned char result[20], const char *path, + const unsigned char base[20], const unsigned char a[20], + const unsigned char b[20]) +{ + struct commit *commit_base, *commit_a, *commit_b; + int parent_count; + struct object_array merges; + + int i; + + /* store a in result in case we fail */ + hashcpy(result, a); + + /* we can not handle deletion conflicts */ + if (is_null_sha1(base)) + return 0; + if (is_null_sha1(a)) + return 0; + if (is_null_sha1(b)) + return 0; + + if (add_submodule_odb(path)) { + MERGE_WARNING(path, "not checked out"); + return 0; + } + + if (!(commit_base = lookup_commit_reference(base)) || + !(commit_a = lookup_commit_reference(a)) || + !(commit_b = lookup_commit_reference(b))) { + MERGE_WARNING(path, "commits not present"); + return 0; + } + + /* check whether both changes are forward */ + if (!in_merge_bases(commit_base, &commit_a, 1) || + !in_merge_bases(commit_base, &commit_b, 1)) { + MERGE_WARNING(path, "commits don't follow merge-base"); + return 0; + } + + /* Case #1: a is contained in b or vice versa */ + if (in_merge_bases(commit_a, &commit_b, 1)) { + hashcpy(result, b); + return 1; + } + if (in_merge_bases(commit_b, &commit_a, 1)) { + hashcpy(result, a); + return 1; + } + + /* + * Case #2: There are one or more merges that contain a and b in + * the submodule. If there is only one, then present it as a + * suggestion to the user, but leave it marked unmerged so the + * user needs to confirm the resolution. + */ + + /* find commit which merges them */ + parent_count = find_first_merges(&merges, path, commit_a, commit_b); + switch (parent_count) { + case 0: + MERGE_WARNING(path, "merge following commits not found"); + break; + + case 1: + MERGE_WARNING(path, "not fast-forward"); + fprintf(stderr, "Found a possible merge resolution " + "for the submodule:\n"); + print_commit((struct commit *) merges.objects[0].item); + fprintf(stderr, + "If this is correct simply add it to the index " + "for example\n" + "by using:\n\n" + " git update-index --cacheinfo 160000 %s \"%s\"\n\n" + "which will accept this suggestion.\n", + sha1_to_hex(merges.objects[0].item->sha1), path); + break; + + default: + MERGE_WARNING(path, "multiple merges found"); + for (i = 0; i < merges.nr; i++) + print_commit((struct commit *) merges.objects[i].item); + } + + free(merges.objects); + return 0; +} |