Merge branch 'lt/unpack-trees'

* lt/unpack-trees:
  unpack_trees(): fix diff-index regression.
  traverse_trees_recursive(): propagate merge errors up
  unpack_trees(): minor memory leak fix in unused destination index
  Make 'unpack_trees()' have a separate source and destination index
  Make 'unpack_trees()' take the index to work on as an argument
  Add 'const' where appropriate to index handling functions
  Fix tree-walking compare_entry() in the presense of --prefix
  Move 'unpack_trees()' over to 'traverse_trees()' interface
  Make 'traverse_trees()' traverse conflicting DF entries in parallel
  Add return value to 'traverse_tree()' callback
  Make 'traverse_tree()' use linked structure rather than 'const char *base'
  Add 'df_name_compare()' helper function

builtin-checkout.c

@@ -152,13 +152,16 @@ static int reset_to_new(struct tree *tree, int quiet)
 {
 	struct unpack_trees_options opts;
 	struct tree_desc tree_desc;
+
 	memset(&opts, 0, sizeof(opts));
 	opts.head_idx = -1;
 	opts.update = 1;
 	opts.reset = 1;
 	opts.merge = 1;
 	opts.fn = oneway_merge;
 	opts.verbose_update = !quiet;
+	opts.src_index = &the_index;
+	opts.dst_index = &the_index;
 	parse_tree(tree);
 	init_tree_desc(&tree_desc, tree->buffer, tree->size);
 	if (unpack_trees(1, &tree_desc, &opts))
@@ -170,13 +173,16 @@ static void reset_clean_to_new(struct tree *tree, int quiet)
 {
 	struct unpack_trees_options opts;
 	struct tree_desc tree_desc;
+
 	memset(&opts, 0, sizeof(opts));
 	opts.head_idx = -1;
 	opts.skip_unmerged = 1;
 	opts.reset = 1;
 	opts.merge = 1;
 	opts.fn = oneway_merge;
 	opts.verbose_update = !quiet;
+	opts.src_index = &the_index;
+	opts.dst_index = &the_index;
 	parse_tree(tree);
 	init_tree_desc(&tree_desc, tree->buffer, tree->size);
 	if (unpack_trees(1, &tree_desc, &opts))
@@ -224,8 +230,11 @@ static int merge_working_tree(struct checkout_opts *opts,
 		struct tree_desc trees[2];
 		struct tree *tree;
 		struct unpack_trees_options topts;
+
 		memset(&topts, 0, sizeof(topts));
 		topts.head_idx = -1;
+		topts.src_index = &the_index;
+		topts.dst_index = &the_index;
 
 		refresh_cache(REFRESH_QUIET);
 

builtin-commit.c

@@ -198,6 +198,8 @@ static void create_base_index(void)
 	opts.head_idx = 1;
 	opts.index_only = 1;
 	opts.merge = 1;
+	opts.src_index = &the_index;
+	opts.dst_index = &the_index;
 
 	opts.fn = oneway_merge;
 	tree = parse_tree_indirect(head_sha1);

builtin-merge-recursive.c

@@ -213,6 +213,8 @@ static int git_merge_trees(int index_only,
 	opts.merge = 1;
 	opts.head_idx = 2;
 	opts.fn = threeway_merge;
+	opts.src_index = &the_index;
+	opts.dst_index = &the_index;
 
 	init_tree_desc_from_tree(t+0, common);
 	init_tree_desc_from_tree(t+1, head);

builtin-read-tree.c

@@ -102,6 +102,8 @@ int cmd_read_tree(int argc, const char **argv, const char *unused_prefix)
 
 	memset(&opts, 0, sizeof(opts));
 	opts.head_idx = -1;
+	opts.src_index = &the_index;
+	opts.dst_index = &the_index;
 
 	git_config(git_default_config);
 
@@ -220,27 +222,6 @@ int cmd_read_tree(int argc, const char **argv, const char *unused_prefix)
 	if ((opts.dir && !opts.update))
 		die("--exclude-per-directory is meaningless unless -u");
 
-	if (opts.prefix) {
-		int pfxlen = strlen(opts.prefix);
-		int pos;
-		if (opts.prefix[pfxlen-1] != '/')
-			die("prefix must end with /");
-		if (stage != 2)
-			die("binding merge takes only one tree");
-		pos = cache_name_pos(opts.prefix, pfxlen);
-		if (0 <= pos)
-			die("corrupt index file");
-		pos = -pos-1;
-		if (pos < active_nr &&
-		    !strncmp(active_cache[pos]->name, opts.prefix, pfxlen))
-			die("subdirectory '%s' already exists.", opts.prefix);
-		pos = cache_name_pos(opts.prefix, pfxlen-1);
-		if (0 <= pos)
-			die("file '%.*s' already exists.",
-					pfxlen-1, opts.prefix);
-		opts.pos = -1 - pos;
-	}
-
 	if (opts.merge) {
 		if (stage < 2)
 			die("just how do you expect me to merge %d trees?", stage-1);

cache.h

@@ -346,12 +346,12 @@ extern void verify_non_filename(const char *prefix, const char *name);
 /* Initialize and use the cache information */
 extern int read_index(struct index_state *);
 extern int read_index_from(struct index_state *, const char *path);
-extern int write_index(struct index_state *, int newfd);
+extern int write_index(const struct index_state *, int newfd);
 extern int discard_index(struct index_state *);
-extern int unmerged_index(struct index_state *);
+extern int unmerged_index(const struct index_state *);
 extern int verify_path(const char *path);
 extern int index_name_exists(struct index_state *istate, const char *name, int namelen);
-extern int index_name_pos(struct index_state *, const char *name, int namelen);
+extern int index_name_pos(const struct index_state *, const char *name, int namelen);
 #define ADD_CACHE_OK_TO_ADD 1		/* Ok to add */
 #define ADD_CACHE_OK_TO_REPLACE 2	/* Ok to replace file/directory */
 #define ADD_CACHE_SKIP_DFCHECK 4	/* Ok to skip DF conflict checks */
@@ -368,8 +368,8 @@ extern int ce_same_name(struct cache_entry *a, struct cache_entry *b);
 #define CE_MATCH_IGNORE_VALID		01
 /* do not check the contents but report dirty on racily-clean entries */
 #define CE_MATCH_RACY_IS_DIRTY	02
-extern int ie_match_stat(struct index_state *, struct cache_entry *, struct stat *, unsigned int);
-extern int ie_modified(struct index_state *, struct cache_entry *, struct stat *, unsigned int);
+extern int ie_match_stat(const struct index_state *, struct cache_entry *, struct stat *, unsigned int);
+extern int ie_modified(const struct index_state *, struct cache_entry *, struct stat *, unsigned int);
 
 extern int ce_path_match(const struct cache_entry *ce, const char **pathspec);
 extern int index_fd(unsigned char *sha1, int fd, struct stat *st, int write_object, enum object_type type, const char *path);
@@ -536,6 +536,7 @@ extern int create_symref(const char *ref, const char *refs_heads_master, const c
 extern int validate_headref(const char *ref);
 
 extern int base_name_compare(const char *name1, int len1, int mode1, const char *name2, int len2, int mode2);
+extern int df_name_compare(const char *name1, int len1, int mode1, const char *name2, int len2, int mode2);
 extern int cache_name_compare(const char *name1, int len1, const char *name2, int len2);
 
 extern void *read_object_with_reference(const unsigned char *sha1,

diff-lib.c

@@ -600,8 +600,7 @@ static void mark_merge_entries(void)
  */
 static void do_oneway_diff(struct unpack_trees_options *o,
 	struct cache_entry *idx,
-	struct cache_entry *tree,
-	int idx_pos, int idx_nr)
+	struct cache_entry *tree)
 {
 	struct rev_info *revs = o->unpack_data;
 	int match_missing, cached;
@@ -642,32 +641,19 @@ static void do_oneway_diff(struct unpack_trees_options *o,
 	show_modified(revs, tree, idx, 1, cached, match_missing);
 }
 
-/*
- * Count how many index entries go with the first one
- */
-static inline int count_skip(const struct cache_entry *src, int pos)
+static inline void skip_same_name(struct cache_entry *ce, struct unpack_trees_options *o)
 {
-	int skip = 1;
-
-	/* We can only have multiple entries if the first one is not stage-0 */
-	if (ce_stage(src)) {
-		struct cache_entry **p = active_cache + pos;
-		int namelen = ce_namelen(src);
-
-		for (;;) {
-			const struct cache_entry *ce;
-			pos++;
-			if (pos >= active_nr)
-				break;
-			ce = *++p;
-			if (ce_namelen(ce) != namelen)
-				break;
-			if (memcmp(ce->name, src->name, namelen))
-				break;
-			skip++;
-		}
+	int len = ce_namelen(ce);
+	const struct index_state *index = o->src_index;
+
+	while (o->pos < index->cache_nr) {
+		struct cache_entry *next = index->cache[o->pos];
+		if (len != ce_namelen(next))
+			break;
+		if (memcmp(ce->name, next->name, len))
+			break;
+		o->pos++;
 	}
-	return skip;
 }
 
 /*
@@ -685,17 +671,14 @@ static inline int count_skip(const struct cache_entry *src, int pos)
  * the fairly complex unpack_trees() semantic requirements, including
  * the skipping, the path matching, the type conflict cases etc.
  */
-static int oneway_diff(struct cache_entry **src,
-	struct unpack_trees_options *o,
-	int index_pos)
+static int oneway_diff(struct cache_entry **src, struct unpack_trees_options *o)
 {
-	int skip = 0;
 	struct cache_entry *idx = src[0];
 	struct cache_entry *tree = src[1];
 	struct rev_info *revs = o->unpack_data;
 
-	if (index_pos >= 0)
-		skip = count_skip(idx, index_pos);
+	if (idx && ce_stage(idx))
+		skip_same_name(idx, o);
 
 	/*
 	 * Unpack-trees generates a DF/conflict entry if
@@ -707,9 +690,9 @@ static int oneway_diff(struct cache_entry **src,
 		tree = NULL;
 
 	if (ce_path_match(idx ? idx : tree, revs->prune_data))
-		do_oneway_diff(o, idx, tree, index_pos, skip);
+		do_oneway_diff(o, idx, tree);
 
-	return skip;
+	return 0;
 }
 
 int run_diff_index(struct rev_info *revs, int cached)
@@ -734,6 +717,8 @@ int run_diff_index(struct rev_info *revs, int cached)
 	opts.merge = 1;
 	opts.fn = oneway_diff;
 	opts.unpack_data = revs;
+	opts.src_index = &the_index;
+	opts.dst_index = NULL;
 
 	init_tree_desc(&t, tree->buffer, tree->size);
 	if (unpack_trees(1, &t, &opts))
@@ -787,6 +772,8 @@ int do_diff_cache(const unsigned char *tree_sha1, struct diff_options *opt)
 	opts.merge = 1;
 	opts.fn = oneway_diff;
 	opts.unpack_data = &revs;
+	opts.src_index = &the_index;
+	opts.dst_index = &the_index;
 
 	init_tree_desc(&t, tree->buffer, tree->size);
 	if (unpack_trees(1, &t, &opts))

hash.c

@@ -9,7 +9,7 @@
  * the existing entry, or the empty slot if none existed. The caller
  * can then look at the (*ptr) to see whether it existed or not.
  */
-static struct hash_table_entry *lookup_hash_entry(unsigned int hash, struct hash_table *table)
+static struct hash_table_entry *lookup_hash_entry(unsigned int hash, const struct hash_table *table)
 {
 	unsigned int size = table->size, nr = hash % size;
 	struct hash_table_entry *array = table->array;
@@ -66,7 +66,7 @@ static void grow_hash_table(struct hash_table *table)
 	free(old_array);
 }
 
-void *lookup_hash(unsigned int hash, struct hash_table *table)
+void *lookup_hash(unsigned int hash, const struct hash_table *table)
 {
 	if (!table->array)
 		return NULL;
@@ -81,7 +81,7 @@ void **insert_hash(unsigned int hash, void *ptr, struct hash_table *table)
 	return insert_hash_entry(hash, ptr, table);
 }
 
-int for_each_hash(struct hash_table *table, int (*fn)(void *))
+int for_each_hash(const struct hash_table *table, int (*fn)(void *))
 {
 	int sum = 0;
 	unsigned int i;

hash.h

@@ -28,9 +28,9 @@ struct hash_table {
 	struct hash_table_entry *array;
 };
 
-extern void *lookup_hash(unsigned int hash, struct hash_table *table);
+extern void *lookup_hash(unsigned int hash, const struct hash_table *table);
 extern void **insert_hash(unsigned int hash, void *ptr, struct hash_table *table);
-extern int for_each_hash(struct hash_table *table, int (*fn)(void *));
+extern int for_each_hash(const struct hash_table *table, int (*fn)(void *));
 extern void free_hash(struct hash_table *table);
 
 static inline void init_hash(struct hash_table *table)