1 files changed, 301 insertions, 0 deletions
diff --git a/tree.c b/tree.c
new file mode 100644
index 0000000000..8c0819fa72
--- /dev/null
+++ b/tree.c
@@ -0,0 +1,301 @@
+#include "cache.h"
+#include "cache-tree.h"
+#include "tree.h"
+#include "blob.h"
+#include "commit.h"
+#include "tag.h"
+#include "tree-walk.h"
+
+const char *tree_type = "tree";
+
+static int read_one_entry_opt(const unsigned char *sha1, const char *base, int baselen, const char *pathname, unsigned mode, int stage, int opt)
+{
+	int len;
+	unsigned int size;
+	struct cache_entry *ce;
+
+	if (S_ISDIR(mode))
+		return READ_TREE_RECURSIVE;
+
+	len = strlen(pathname);
+	size = cache_entry_size(baselen + len);
+	ce = xcalloc(1, size);
+
+	ce->ce_mode = create_ce_mode(mode);
+	ce->ce_flags = create_ce_flags(baselen + len, stage);
+	memcpy(ce->name, base, baselen);
+	memcpy(ce->name + baselen, pathname, len+1);
+	hashcpy(ce->sha1, sha1);
+	return add_cache_entry(ce, opt);
+}
+
+static int read_one_entry(const unsigned char *sha1, const char *base, int baselen, const char *pathname, unsigned mode, int stage)
+{
+	return read_one_entry_opt(sha1, base, baselen, pathname, mode, stage,
+				  ADD_CACHE_OK_TO_ADD|ADD_CACHE_SKIP_DFCHECK);
+}
+
+/*
+ * This is used when the caller knows there is no existing entries at
+ * the stage that will conflict with the entry being added.
+ */
+static int read_one_entry_quick(const unsigned char *sha1, const char *base, int baselen, const char *pathname, unsigned mode, int stage)
+{
+	return read_one_entry_opt(sha1, base, baselen, pathname, mode, stage,
+				  ADD_CACHE_JUST_APPEND);
+}
+
+static int match_tree_entry(const char *base, int baselen, const char *path, unsigned int mode, const char **paths)
+{
+	const char *match;
+	int pathlen;
+
+	if (!paths)
+		return 1;
+	pathlen = strlen(path);
+	while ((match = *paths++) != NULL) {
+		int matchlen = strlen(match);
+
+		if (baselen >= matchlen) {
+			/* If it doesn't match, move along... */
+			if (strncmp(base, match, matchlen))
+				continue;
+			/* The base is a subdirectory of a path which was specified. */
+			return 1;
+		}
+
+		/* Does the base match? */
+		if (strncmp(base, match, baselen))
+			continue;
+
+		match += baselen;
+		matchlen -= baselen;
+
+		if (pathlen > matchlen)
+			continue;
+
+		if (matchlen > pathlen) {
+			if (match[pathlen] != '/')
+				continue;
+			if (!S_ISDIR(mode))
+				continue;
+		}
+
+		if (strncmp(path, match, pathlen))
+			continue;
+
+		return 1;
+	}
+	return 0;
+}
+
+int read_tree_recursive(struct tree *tree,
+			const char *base, int baselen,
+			int stage, const char **match,
+			read_tree_fn_t fn)
+{
+	struct tree_desc desc;
+	struct name_entry entry;
+
+	if (parse_tree(tree))
+		return -1;
+
+	init_tree_desc(&desc, tree->buffer, tree->size);
+
+	while (tree_entry(&desc, &entry)) {
+		if (!match_tree_entry(base, baselen, entry.path, entry.mode, match))
+			continue;
+
+		switch (fn(entry.sha1, base, baselen, entry.path, entry.mode, stage)) {
+		case 0:
+			continue;
+		case READ_TREE_RECURSIVE:
+			break;;
+		default:
+			return -1;
+		}
+		if (S_ISDIR(entry.mode)) {
+			int retval;
+			char *newbase;
+			unsigned int pathlen = tree_entry_len(entry.path, entry.sha1);
+
+			newbase = xmalloc(baselen + 1 + pathlen);
+			memcpy(newbase, base, baselen);
+			memcpy(newbase + baselen, entry.path, pathlen);
+			newbase[baselen + pathlen] = '/';
+			retval = read_tree_recursive(lookup_tree(entry.sha1),
+						     newbase,
+						     baselen + pathlen + 1,
+						     stage, match, fn);
+			free(newbase);
+			if (retval)
+				return -1;
+			continue;
+		}
+	}
+	return 0;
+}
+
+static int cmp_cache_name_compare(const void *a_, const void *b_)
+{
+	const struct cache_entry *ce1, *ce2;
+
+	ce1 = *((const struct cache_entry **)a_);
+	ce2 = *((const struct cache_entry **)b_);
+	return cache_name_compare(ce1->name, ntohs(ce1->ce_flags),
+				  ce2->name, ntohs(ce2->ce_flags));
+}
+
+int read_tree(struct tree *tree, int stage, const char **match)
+{
+	read_tree_fn_t fn = NULL;
+	int i, err;
+
+	/*
+	 * Currently the only existing callers of this function all
+	 * call it with stage=1 and after making sure there is nothing
+	 * at that stage; we could always use read_one_entry_quick().
+	 *
+	 * But when we decide to straighten out git-read-tree not to
+	 * use unpack_trees() in some cases, this will probably start
+	 * to matter.
+	 */
+
+	/*
+	 * See if we have cache entry at the stage.  If so,
+	 * do it the original slow way, otherwise, append and then
+	 * sort at the end.
+	 */
+	for (i = 0; !fn && i < active_nr; i++) {
+		struct cache_entry *ce = active_cache[i];
+		if (ce_stage(ce) == stage)
+			fn = read_one_entry;
+	}
+
+	if (!fn)
+		fn = read_one_entry_quick;
+	err = read_tree_recursive(tree, "", 0, stage, match, fn);
+	if (fn == read_one_entry || err)
+		return err;
+
+	/*
+	 * Sort the cache entry -- we need to nuke the cache tree, though.
+	 */
+	cache_tree_free(&active_cache_tree);
+	qsort(active_cache, active_nr, sizeof(active_cache[0]),
+	      cmp_cache_name_compare);
+	return 0;
+}
+
+struct tree *lookup_tree(const unsigned char *sha1)
+{
+	struct object *obj = lookup_object(sha1);
+	if (!obj)
+		return create_object(sha1, OBJ_TREE, alloc_tree_node());
+	if (!obj->type)
+		obj->type = OBJ_TREE;
+	if (obj->type != OBJ_TREE) {
+		error("Object %s is a %s, not a tree",
+		      sha1_to_hex(sha1), typename(obj->type));
+		return NULL;
+	}
+	return (struct tree *) obj;
+}
+
+/*
+ * NOTE! Tree refs to external git repositories
+ * (ie gitlinks) do not count as real references.
+ *
+ * You don't have to have those repositories
+ * available at all, much less have the objects
+ * accessible from the current repository.
+ */
+static void track_tree_refs(struct tree *item)
+{
+	int n_refs = 0, i;
+	struct object_refs *refs;
+	struct tree_desc desc;
+	struct name_entry entry;
+
+	/* Count how many entries there are.. */
+	init_tree_desc(&desc, item->buffer, item->size);
+	while (tree_entry(&desc, &entry)) {
+		if (S_ISGITLINK(entry.mode))
+			continue;
+		n_refs++;
+	}
+
+	/* Allocate object refs and walk it again.. */
+	i = 0;
+	refs = alloc_object_refs(n_refs);
+	init_tree_desc(&desc, item->buffer, item->size);
+	while (tree_entry(&desc, &entry)) {
+		struct object *obj;
+
+		if (S_ISGITLINK(entry.mode))
+			continue;
+		if (S_ISDIR(entry.mode))
+			obj = &lookup_tree(entry.sha1)->object;
+		else if (S_ISREG(entry.mode) || S_ISLNK(entry.mode))
+			obj = &lookup_blob(entry.sha1)->object;
+		else {
+			warning("in tree %s: entry %s has bad mode %.6o\n",
+			     sha1_to_hex(item->object.sha1), entry.path, entry.mode);
+			obj = lookup_unknown_object(entry.sha1);
+		}
+		refs->ref[i++] = obj;
+	}
+	set_object_refs(&item->object, refs);
+}
+
+int parse_tree_buffer(struct tree *item, void *buffer, unsigned long size)
+{
+	if (item->object.parsed)
+		return 0;
+	item->object.parsed = 1;
+	item->buffer = buffer;
+	item->size = size;
+
+	if (track_object_refs)
+		track_tree_refs(item);
+	return 0;
+}
+
+int parse_tree(struct tree *item)
+{
+	 enum object_type type;
+	 void *buffer;
+	 unsigned long size;
+
+	if (item->object.parsed)
+		return 0;
+	buffer = read_sha1_file(item->object.sha1, &type, &size);
+	if (!buffer)
+		return error("Could not read %s",
+			     sha1_to_hex(item->object.sha1));
+	if (type != OBJ_TREE) {
+		free(buffer);
+		return error("Object %s not a tree",
+			     sha1_to_hex(item->object.sha1));
+	}
+	return parse_tree_buffer(item, buffer, size);
+}
+
+struct tree *parse_tree_indirect(const unsigned char *sha1)
+{
+	struct object *obj = parse_object(sha1);
+	do {
+		if (!obj)
+			return NULL;
+		if (obj->type == OBJ_TREE)
+			return (struct tree *) obj;
+		else if (obj->type == OBJ_COMMIT)
+			obj = &(((struct commit *) obj)->tree->object);
+		else if (obj->type == OBJ_TAG)
+			obj = ((struct tag *) obj)->tagged;
+		else
+			return NULL;
+		if (!obj->parsed)
+			parse_object(obj->sha1);
+	} while (1);
+}