From 076b0adcf9dac7bd9d18624087f679cc811aeb77 Mon Sep 17 00:00:00 2001 From: Johannes Schindelin Date: Sun, 30 Jul 2006 20:26:15 +0200 Subject: read-tree: move merge functions to the library This will allow merge-recursive to use the read-tree functionality without exec()ing git-read-tree. Signed-off-by: Johannes Schindelin Signed-off-by: Junio C Hamano --- builtin-read-tree.c | 398 +--------------------------------------------------- 1 file changed, 1 insertion(+), 397 deletions(-) (limited to 'builtin-read-tree.c') diff --git a/builtin-read-tree.c b/builtin-read-tree.c index 6bc042f852..8869cedea1 100644 --- a/builtin-read-tree.c +++ b/builtin-read-tree.c @@ -3,10 +3,8 @@ * * Copyright (C) Linus Torvalds, 2005 */ -#define DBRT_DEBUG 1 #include "cache.h" - #include "object.h" #include "tree.h" #include "tree-walk.h" @@ -16,12 +14,6 @@ static struct object_list *trees = NULL; -static void reject_merge(struct cache_entry *ce) -{ - die("Entry '%s' would be overwritten by merge. Cannot merge.", - ce->name); -} - static int list_tree(unsigned char *sha1) { struct tree *tree = parse_tree_indirect(sha1); @@ -31,394 +23,6 @@ static int list_tree(unsigned char *sha1) return 0; } -static int same(struct cache_entry *a, struct cache_entry *b) -{ - if (!!a != !!b) - return 0; - if (!a && !b) - return 1; - return a->ce_mode == b->ce_mode && - !memcmp(a->sha1, b->sha1, 20); -} - - -/* - * When a CE gets turned into an unmerged entry, we - * want it to be up-to-date - */ -static void verify_uptodate(struct cache_entry *ce, - struct unpack_trees_options *o) -{ - struct stat st; - - if (o->index_only || o->reset) - return; - - if (!lstat(ce->name, &st)) { - unsigned changed = ce_match_stat(ce, &st, 1); - if (!changed) - return; - errno = 0; - } - if (o->reset) { - ce->ce_flags |= htons(CE_UPDATE); - return; - } - if (errno == ENOENT) - return; - die("Entry '%s' not uptodate. Cannot merge.", ce->name); -} - -static void invalidate_ce_path(struct cache_entry *ce) -{ - if (ce) - cache_tree_invalidate_path(active_cache_tree, ce->name); -} - -/* - * We do not want to remove or overwrite a working tree file that - * is not tracked. - */ -static void verify_absent(const char *path, const char *action, - struct unpack_trees_options *o) -{ - struct stat st; - - if (o->index_only || o->reset || !o->update) - return; - if (!lstat(path, &st)) - die("Untracked working tree file '%s' " - "would be %s by merge.", path, action); -} - -static int merged_entry(struct cache_entry *merge, struct cache_entry *old, - struct unpack_trees_options *o) -{ - merge->ce_flags |= htons(CE_UPDATE); - if (old) { - /* - * See if we can re-use the old CE directly? - * That way we get the uptodate stat info. - * - * This also removes the UPDATE flag on - * a match. - */ - if (same(old, merge)) { - *merge = *old; - } else { - verify_uptodate(old, o); - invalidate_ce_path(old); - } - } - else { - verify_absent(merge->name, "overwritten", o); - invalidate_ce_path(merge); - } - - merge->ce_flags &= ~htons(CE_STAGEMASK); - add_cache_entry(merge, ADD_CACHE_OK_TO_ADD|ADD_CACHE_OK_TO_REPLACE); - return 1; -} - -static int deleted_entry(struct cache_entry *ce, struct cache_entry *old, - struct unpack_trees_options *o) -{ - if (old) - verify_uptodate(old, o); - else - verify_absent(ce->name, "removed", o); - ce->ce_mode = 0; - add_cache_entry(ce, ADD_CACHE_OK_TO_ADD|ADD_CACHE_OK_TO_REPLACE); - invalidate_ce_path(ce); - return 1; -} - -static int keep_entry(struct cache_entry *ce) -{ - add_cache_entry(ce, ADD_CACHE_OK_TO_ADD); - return 1; -} - -#if DBRT_DEBUG -static void show_stage_entry(FILE *o, - const char *label, const struct cache_entry *ce) -{ - if (!ce) - fprintf(o, "%s (missing)\n", label); - else - fprintf(o, "%s%06o %s %d\t%s\n", - label, - ntohl(ce->ce_mode), - sha1_to_hex(ce->sha1), - ce_stage(ce), - ce->name); -} -#endif - -static int threeway_merge(struct cache_entry **stages, - struct unpack_trees_options *o) -{ - struct cache_entry *index; - struct cache_entry *head; - struct cache_entry *remote = stages[o->head_idx + 1]; - int count; - int head_match = 0; - int remote_match = 0; - const char *path = NULL; - - int df_conflict_head = 0; - int df_conflict_remote = 0; - - int any_anc_missing = 0; - int no_anc_exists = 1; - int i; - - for (i = 1; i < o->head_idx; i++) { - if (!stages[i]) - any_anc_missing = 1; - else { - if (!path) - path = stages[i]->name; - no_anc_exists = 0; - } - } - - index = stages[0]; - head = stages[o->head_idx]; - - if (head == &o->df_conflict_entry) { - df_conflict_head = 1; - head = NULL; - } - - if (remote == &o->df_conflict_entry) { - df_conflict_remote = 1; - remote = NULL; - } - - if (!path && index) - path = index->name; - if (!path && head) - path = head->name; - if (!path && remote) - path = remote->name; - - /* First, if there's a #16 situation, note that to prevent #13 - * and #14. - */ - if (!same(remote, head)) { - for (i = 1; i < o->head_idx; i++) { - if (same(stages[i], head)) { - head_match = i; - } - if (same(stages[i], remote)) { - remote_match = i; - } - } - } - - /* We start with cases where the index is allowed to match - * something other than the head: #14(ALT) and #2ALT, where it - * is permitted to match the result instead. - */ - /* #14, #14ALT, #2ALT */ - if (remote && !df_conflict_head && head_match && !remote_match) { - if (index && !same(index, remote) && !same(index, head)) - reject_merge(index); - return merged_entry(remote, index, o); - } - /* - * If we have an entry in the index cache, then we want to - * make sure that it matches head. - */ - if (index && !same(index, head)) { - reject_merge(index); - } - - if (head) { - /* #5ALT, #15 */ - if (same(head, remote)) - return merged_entry(head, index, o); - /* #13, #3ALT */ - if (!df_conflict_remote && remote_match && !head_match) - return merged_entry(head, index, o); - } - - /* #1 */ - if (!head && !remote && any_anc_missing) - return 0; - - /* Under the new "aggressive" rule, we resolve mostly trivial - * cases that we historically had git-merge-one-file resolve. - */ - if (o->aggressive) { - int head_deleted = !head && !df_conflict_head; - int remote_deleted = !remote && !df_conflict_remote; - /* - * Deleted in both. - * Deleted in one and unchanged in the other. - */ - if ((head_deleted && remote_deleted) || - (head_deleted && remote && remote_match) || - (remote_deleted && head && head_match)) { - if (index) - return deleted_entry(index, index, o); - else if (path) - verify_absent(path, "removed", o); - return 0; - } - /* - * Added in both, identically. - */ - if (no_anc_exists && head && remote && same(head, remote)) - return merged_entry(head, index, o); - - } - - /* Below are "no merge" cases, which require that the index be - * up-to-date to avoid the files getting overwritten with - * conflict resolution files. - */ - if (index) { - verify_uptodate(index, o); - } - else if (path) - verify_absent(path, "overwritten", o); - - o->nontrivial_merge = 1; - - /* #2, #3, #4, #6, #7, #9, #11. */ - count = 0; - if (!head_match || !remote_match) { - for (i = 1; i < o->head_idx; i++) { - if (stages[i]) { - keep_entry(stages[i]); - count++; - break; - } - } - } -#if DBRT_DEBUG - else { - fprintf(stderr, "read-tree: warning #16 detected\n"); - show_stage_entry(stderr, "head ", stages[head_match]); - show_stage_entry(stderr, "remote ", stages[remote_match]); - } -#endif - if (head) { count += keep_entry(head); } - if (remote) { count += keep_entry(remote); } - return count; -} - -/* - * Two-way merge. - * - * The rule is to "carry forward" what is in the index without losing - * information across a "fast forward", favoring a successful merge - * over a merge failure when it makes sense. For details of the - * "carry forward" rule, please see . - * - */ -static int twoway_merge(struct cache_entry **src, - struct unpack_trees_options *o) -{ - struct cache_entry *current = src[0]; - struct cache_entry *oldtree = src[1], *newtree = src[2]; - - if (o->merge_size != 2) - return error("Cannot do a twoway merge of %d trees", - o->merge_size); - - if (current) { - if ((!oldtree && !newtree) || /* 4 and 5 */ - (!oldtree && newtree && - same(current, newtree)) || /* 6 and 7 */ - (oldtree && newtree && - same(oldtree, newtree)) || /* 14 and 15 */ - (oldtree && newtree && - !same(oldtree, newtree) && /* 18 and 19*/ - same(current, newtree))) { - return keep_entry(current); - } - else if (oldtree && !newtree && same(current, oldtree)) { - /* 10 or 11 */ - return deleted_entry(oldtree, current, o); - } - else if (oldtree && newtree && - same(current, oldtree) && !same(current, newtree)) { - /* 20 or 21 */ - return merged_entry(newtree, current, o); - } - else { - /* all other failures */ - if (oldtree) - reject_merge(oldtree); - if (current) - reject_merge(current); - if (newtree) - reject_merge(newtree); - return -1; - } - } - else if (newtree) - return merged_entry(newtree, current, o); - else - return deleted_entry(oldtree, current, o); -} - -/* - * Bind merge. - * - * Keep the index entries at stage0, collapse stage1 but make sure - * stage0 does not have anything there. - */ -static int bind_merge(struct cache_entry **src, - struct unpack_trees_options *o) -{ - struct cache_entry *old = src[0]; - struct cache_entry *a = src[1]; - - if (o->merge_size != 1) - return error("Cannot do a bind merge of %d trees\n", - o->merge_size); - if (a && old) - die("Entry '%s' overlaps. Cannot bind.", a->name); - if (!a) - return keep_entry(old); - else - return merged_entry(a, NULL, o); -} - -/* - * One-way merge. - * - * The rule is: - * - take the stat information from stage0, take the data from stage1 - */ -static int oneway_merge(struct cache_entry **src, - struct unpack_trees_options *o) -{ - struct cache_entry *old = src[0]; - struct cache_entry *a = src[1]; - - if (o->merge_size != 1) - return error("Cannot do a oneway merge of %d trees", - o->merge_size); - - if (!a) - return deleted_entry(old, old, o); - if (old && same(old, a)) { - if (o->reset) { - struct stat st; - if (lstat(old->name, &st) || - ce_match_stat(old, &st, 1)) - old->ce_flags |= htons(CE_UPDATE); - } - return keep_entry(old); - } - return merged_entry(a, old, o); -} - static int read_cache_unmerged(void) { int i; @@ -432,7 +36,7 @@ static int read_cache_unmerged(void) if (ce_stage(ce)) { if (last && !strcmp(ce->name, last->name)) continue; - invalidate_ce_path(ce); + cache_tree_invalidate_path(active_cache_tree, ce->name); last = ce; ce->ce_mode = 0; ce->ce_flags &= ~htons(CE_STAGEMASK); -- cgit v1.2.3