From 8b944b5678efcbbbedfd555e5eef1500dc6074d1 Mon Sep 17 00:00:00 2001 From: Junio C Hamano Date: Wed, 10 Jan 2007 11:20:58 -0800 Subject: [PATCH] merge-recursive: do not use on-file index when not needed. This revamps the merge-recursive implementation following the outline in: Message-ID: <7v8xgileza.fsf@assigned-by-dhcp.cox.net> There is no need to write out the index until the very end just once from merge-recursive. Also there is no need to write out the resulting tree object for the simple case of merging with a single merge base. Signed-off-by: Junio C Hamano --- merge-recursive.c | 169 +++++++++++++--------------------------------- 1 file changed, 46 insertions(+), 123 deletions(-) diff --git a/merge-recursive.c b/merge-recursive.c index aab4c3458..523702130 100644 --- a/merge-recursive.c +++ b/merge-recursive.c @@ -110,35 +110,6 @@ static void output_commit_title(struct commit *commit) } } -static const char *current_index_file = NULL; -static const char *original_index_file; -static const char *temporary_index_file; -static int cache_dirty = 0; - -static int flush_cache(void) -{ - /* flush temporary index */ - struct lock_file *lock = xcalloc(1, sizeof(struct lock_file)); - int fd = hold_lock_file_for_update(lock, current_index_file, 1); - if (write_cache(fd, active_cache, active_nr) || - close(fd) || commit_lock_file(lock)) - die ("unable to write %s", current_index_file); - discard_cache(); - cache_dirty = 0; - return 0; -} - -static void setup_index(int temp) -{ - current_index_file = temp ? temporary_index_file: original_index_file; - if (cache_dirty) { - discard_cache(); - cache_dirty = 0; - } - unlink(temporary_index_file); - discard_cache(); -} - static struct cache_entry *make_cache_entry(unsigned int mode, const unsigned char *sha1, const char *path, int stage, int refresh) { @@ -167,9 +138,6 @@ static int add_cacheinfo(unsigned int mode, const unsigned char *sha1, const char *path, int stage, int refresh, int options) { struct cache_entry *ce; - if (!cache_dirty) - read_cache_from(current_index_file); - cache_dirty++; ce = make_cache_entry(mode, sha1 ? sha1 : null_sha1, path, stage, refresh); if (!ce) return error("cache_addinfo failed: %s", strerror(cache_errno)); @@ -187,26 +155,6 @@ static int add_cacheinfo(unsigned int mode, const unsigned char *sha1, */ static int index_only = 0; -static int git_read_tree(struct tree *tree) -{ - int rc; - struct object_list *trees = NULL; - struct unpack_trees_options opts; - - if (cache_dirty) - die("read-tree with dirty cache"); - - memset(&opts, 0, sizeof(opts)); - object_list_append(&tree->object, &trees); - rc = unpack_trees(trees, &opts); - cache_tree_free(&active_cache_tree); - - if (rc == 0) - cache_dirty = 1; - - return rc; -} - static int git_merge_trees(int index_only, struct tree *common, struct tree *head, @@ -216,11 +164,6 @@ static int git_merge_trees(int index_only, struct object_list *trees = NULL; struct unpack_trees_options opts; - if (!cache_dirty) { - read_cache_from(current_index_file); - cache_dirty = 1; - } - memset(&opts, 0, sizeof(opts)); if (index_only) opts.index_only = 1; @@ -236,39 +179,37 @@ static int git_merge_trees(int index_only, rc = unpack_trees(trees, &opts); cache_tree_free(&active_cache_tree); - - cache_dirty = 1; - return rc; } +static int unmerged_index(void) +{ + int i; + for (i = 0; i < active_nr; i++) { + struct cache_entry *ce = active_cache[i]; + if (ce_stage(ce)) + return 1; + } + return 0; +} + static struct tree *git_write_tree(void) { struct tree *result = NULL; - if (cache_dirty) { - unsigned i; - for (i = 0; i < active_nr; i++) { - struct cache_entry *ce = active_cache[i]; - if (ce_stage(ce)) - return NULL; - } - } else - read_cache_from(current_index_file); + if (unmerged_index()) + return NULL; if (!active_cache_tree) active_cache_tree = cache_tree(); if (!cache_tree_fully_valid(active_cache_tree) && - cache_tree_update(active_cache_tree, - active_cache, active_nr, 0, 0) < 0) + cache_tree_update(active_cache_tree, + active_cache, active_nr, 0, 0) < 0) die("error building trees"); result = lookup_tree(active_cache_tree->sha1); - flush_cache(); - cache_dirty = 0; - return result; } @@ -331,10 +272,7 @@ static struct path_list *get_unmerged(void) int i; unmerged->strdup_paths = 1; - if (!cache_dirty) { - read_cache_from(current_index_file); - cache_dirty++; - } + for (i = 0; i < active_nr; i++) { struct path_list_item *item; struct stage_data *e; @@ -469,9 +407,6 @@ static int remove_file(int clean, const char *path, int no_wd) int update_working_directory = !index_only && !no_wd; if (update_cache) { - if (!cache_dirty) - read_cache_from(current_index_file); - cache_dirty++; if (remove_file_from_cache(path)) return -1; } @@ -1105,9 +1040,7 @@ static int merge_trees(struct tree *head, sha1_to_hex(head->object.sha1), sha1_to_hex(merge->object.sha1)); - *result = git_write_tree(); - - if (!*result) { + if (unmerged_index()) { struct path_list *entries, *re_head, *re_merge; int i; path_list_clear(¤t_file_set, 1); @@ -1128,17 +1061,11 @@ static int merge_trees(struct tree *head, if (!process_entry(path, e, branch1, branch2)) clean = 0; } - if (cache_dirty) - flush_cache(); path_list_clear(re_merge, 0); path_list_clear(re_head, 0); path_list_clear(entries, 1); - if (clean || index_only) - *result = git_write_tree(); - else - *result = NULL; } else { clean = 1; printf("merging of trees %s and %s resulted in %s\n", @@ -1146,6 +1073,8 @@ static int merge_trees(struct tree *head, sha1_to_hex(merge->object.sha1), sha1_to_hex((*result)->object.sha1)); } + if (index_only) + *result = git_write_tree(); return clean; } @@ -1170,10 +1099,10 @@ static int merge(struct commit *h1, const char *branch1, const char *branch2, int call_depth /* =0 */, - struct commit *ancestor /* =None */, + struct commit_list *ca, struct commit **result) { - struct commit_list *ca = NULL, *iter; + struct commit_list *iter; struct commit *merged_common_ancestors; struct tree *mrtree; int clean; @@ -1182,10 +1111,10 @@ static int merge(struct commit *h1, output_commit_title(h1); output_commit_title(h2); - if (ancestor) - commit_list_insert(ancestor, &ca); - else - ca = reverse_commit_list(get_merge_bases(h1, h2, 1)); + if (!ca) { + ca = get_merge_bases(h1, h2, 1); + ca = reverse_commit_list(ca); + } output("found %u common ancestor(s):", commit_list_count(ca)); for (iter = ca; iter; iter = iter->next) @@ -1211,6 +1140,7 @@ static int merge(struct commit *h1, * merge_trees has always overwritten it: the commited * "conflicts" were already resolved. */ + discard_cache(); merge(merged_common_ancestors, iter->item, "Temporary merge branch 1", "Temporary merge branch 2", @@ -1223,25 +1153,21 @@ static int merge(struct commit *h1, die("merge returned no commit"); } + discard_cache(); if (call_depth == 0) { - setup_index(0 /* $GIT_DIR/index */); + read_cache(); index_only = 0; - } else { - setup_index(1 /* temporary index */); - git_read_tree(h1->tree); + } else index_only = 1; - } clean = merge_trees(h1->tree, h2->tree, merged_common_ancestors->tree, branch1, branch2, &mrtree); - if (!ancestor && (clean || index_only)) { + if (index_only) { *result = make_virtual_commit(mrtree, "merged tree"); commit_list_insert(h1, &(*result)->parents); commit_list_insert(h2, &(*result)->parents->next); - } else - *result = NULL; - + } return clean; } @@ -1277,19 +1203,16 @@ static struct commit *get_ref(const char *ref) int main(int argc, char *argv[]) { - static const char *bases[2]; + static const char *bases[20]; static unsigned bases_count = 0; int i, clean; const char *branch1, *branch2; struct commit *result, *h1, *h2; + struct commit_list *ca = NULL; + struct lock_file *lock = xcalloc(1, sizeof(struct lock_file)); + int index_fd; git_config(git_default_config); /* core.filemode */ - original_index_file = getenv(INDEX_ENVIRONMENT); - - if (!original_index_file) - original_index_file = xstrdup(git_path("index")); - - temporary_index_file = xstrdup(git_path("mrg-rcrsv-tmp-idx")); if (argc < 4) die("Usage: %s ... -- ...\n", argv[0]); @@ -1313,18 +1236,18 @@ int main(int argc, char *argv[]) branch2 = better_branch_name(branch2); printf("Merging %s with %s\n", branch1, branch2); - if (bases_count == 1) { - struct commit *ancestor = get_ref(bases[0]); - clean = merge(h1, h2, branch1, branch2, 0, ancestor, &result); - } else - clean = merge(h1, h2, branch1, branch2, 0, NULL, &result); + index_fd = hold_lock_file_for_update(lock, get_index_file(), 1); - if (cache_dirty) - flush_cache(); + for (i = 0; i < bases_count; i++) { + struct commit *ancestor = get_ref(bases[i]); + ca = commit_list_insert(ancestor, &ca); + } + clean = merge(h1, h2, branch1, branch2, 0, ca, &result); + + if (active_cache_changed && + (write_cache(index_fd, active_cache, active_nr) || + close(index_fd) || commit_lock_file(lock))) + die ("unable to write %s", get_index_file()); return clean ? 0: 1; } - -/* -vim: sw=8 noet -*/ -- 2.45.2