X-Git-Url: https://git.tokkee.org/?a=blobdiff_plain;f=tree-walk.c;h=8d4b67317f21508a105175686c7ec98a090ed9b5;hb=fcd056a6d23bafb13f991ffb673fb87c7100b8f2;hp=297c6972b9256578f9cd7a92404dda55c8e34a2e;hpb=16a4c6ee0d9a3d07d4d0afbbc4e3467e78065eca;p=git.git

diff --git a/tree-walk.c b/tree-walk.c
index 297c6972b..8d4b67317 100644
--- a/tree-walk.c
+++ b/tree-walk.c
@@ -2,6 +2,44 @@
 #include "tree-walk.h"
 #include "tree.h"
 
+static const char *get_mode(const char *str, unsigned int *modep)
+{
+	unsigned char c;
+	unsigned int mode = 0;
+
+	while ((c = *str++) != ' ') {
+		if (c < '0' || c > '7')
+			return NULL;
+		mode = (mode << 3) + (c - '0');
+	}
+	*modep = mode;
+	return str;
+}
+
+static void decode_tree_entry(struct tree_desc *desc, const void *buf, unsigned long size)
+{
+	const char *path;
+	unsigned int mode, len;
+
+	path = get_mode(buf, &mode);
+	if (!path)
+		die("corrupt tree file");
+	len = strlen(path) + 1;
+
+	/* Initialize the descriptor entry */
+	desc->entry.path = path;
+	desc->entry.mode = mode;
+	desc->entry.sha1 = (const unsigned char *)(path + len);
+}
+
+void init_tree_desc(struct tree_desc *desc, const void *buffer, unsigned long size)
+{
+	desc->buffer = buffer;
+	desc->size = size;
+	if (size)
+		decode_tree_entry(desc, buffer, size);
+}
+
 void *fill_tree_descriptor(struct tree_desc *desc, const unsigned char *sha1)
 {
 	unsigned long size = 0;
@@ -12,16 +50,15 @@ void *fill_tree_descriptor(struct tree_desc *desc, const unsigned char *sha1)
 		if (!buf)
 			die("unable to read tree %s", sha1_to_hex(sha1));
 	}
-	desc->size = size;
-	desc->buf = buf;
+	init_tree_desc(desc, buf, size);
 	return buf;
 }
 
 static int entry_compare(struct name_entry *a, struct name_entry *b)
 {
 	return base_name_compare(
-			a->path, a->pathlen, a->mode,
-			b->path, b->pathlen, b->mode);
+			a->path, tree_entry_len(a->path, a->sha1), a->mode,
+			b->path, tree_entry_len(b->path, b->sha1), b->mode);
 }
 
 static void entry_clear(struct name_entry *a)
@@ -31,79 +68,33 @@ static void entry_clear(struct name_entry *a)
 
 static void entry_extract(struct tree_desc *t, struct name_entry *a)
 {
-	a->sha1 = tree_entry_extract(t, &a->path, &a->mode);
-	a->pathlen = strlen(a->path);
+	*a = t->entry;
 }
 
 void update_tree_entry(struct tree_desc *desc)
 {
-	const void *buf = desc->buf;
+	const void *buf = desc->buffer;
+	const unsigned char *end = desc->entry.sha1 + 20;
 	unsigned long size = desc->size;
-	int len = strlen(buf) + 1 + 20;
+	unsigned long len = end - (const unsigned char *)buf;
 
 	if (size < len)
 		die("corrupt tree file");
-	desc->buf = buf + len;
-	desc->size = size - len;
-}
-
-static const char *get_mode(const char *str, unsigned int *modep)
-{
-	unsigned char c;
-	unsigned int mode = 0;
-
-	while ((c = *str++) != ' ') {
-		if (c < '0' || c > '7')
-			return NULL;
-		mode = (mode << 3) + (c - '0');
-	}
-	*modep = mode;
-	return str;
-}
-
-const unsigned char *tree_entry_extract(struct tree_desc *desc, const char **pathp, unsigned int *modep)
-{
-	const void *tree = desc->buf;
-	unsigned long size = desc->size;
-	int len = strlen(tree)+1;
-	const unsigned char *sha1 = tree + len;
-	const char *path;
-	unsigned int mode;
-
-	path = get_mode(tree, &mode);
-	if (!path || size < len + 20)
-		die("corrupt tree file");
-	*pathp = path;
-	*modep = canon_mode(mode);
-	return sha1;
+	buf = end;
+	size -= len;
+	desc->buffer = buf;
+	desc->size = size;
+	if (size)
+		decode_tree_entry(desc, buf, size);
 }
 
 int tree_entry(struct tree_desc *desc, struct name_entry *entry)
 {
-	const void *tree = desc->buf, *path;
-	unsigned long len, size = desc->size;
-
-	if (!size)
+	if (!desc->size)
 		return 0;
 
-	path = get_mode(tree, &entry->mode);
-	if (!path)
-		die("corrupt tree file");
-
-	entry->path = path;
-	len = strlen(path);
-	entry->pathlen = len;
-
-	path += len + 1;
-	entry->sha1 = path;
-
-	path += 20;
-	len = path - tree;
-	if (len > size)
-		die("corrupt tree file");
-
-	desc->buf = path;
-	desc->size = size - len;
+	*entry = desc->entry;
+	update_tree_entry(desc);
 	return 1;
 }
 
@@ -112,7 +103,6 @@ void traverse_trees(int n, struct tree_desc *t, const char *base, traverse_callb
 	struct name_entry *entry = xmalloc(n*sizeof(*entry));
 
 	for (;;) {
-		struct name_entry entry[3];
 		unsigned long mask = 0;
 		int i, last;
 
@@ -169,7 +159,7 @@ static int find_tree_entry(struct tree_desc *t, const char *name, unsigned char
 
 		sha1 = tree_entry_extract(t, &entry, mode);
 		update_tree_entry(t);
-		entrylen = strlen(entry);
+		entrylen = tree_entry_len(entry, sha1);
 		if (entrylen > namelen)
 			continue;
 		cmp = memcmp(name, entry, entrylen);
@@ -178,7 +168,7 @@ static int find_tree_entry(struct tree_desc *t, const char *name, unsigned char
 		if (cmp < 0)
 			break;
 		if (entrylen == namelen) {
-			memcpy(result, sha1, 20);
+			hashcpy(result, sha1);
 			return 0;
 		}
 		if (name[entrylen] != '/')
@@ -186,7 +176,7 @@ static int find_tree_entry(struct tree_desc *t, const char *name, unsigned char
 		if (!S_ISDIR(*mode))
 			break;
 		if (++entrylen == namelen) {
-			memcpy(result, sha1, 20);
+			hashcpy(result, sha1);
 			return 0;
 		}
 		return get_tree_entry(sha1, name + entrylen, result, mode);
@@ -198,14 +188,21 @@ int get_tree_entry(const unsigned char *tree_sha1, const char *name, unsigned ch
 {
 	int retval;
 	void *tree;
+	unsigned long size;
 	struct tree_desc t;
+	unsigned char root[20];
 
-	tree = read_object_with_reference(tree_sha1, tree_type, &t.size, NULL);
+	tree = read_object_with_reference(tree_sha1, tree_type, &size, root);
 	if (!tree)
 		return -1;
-	t.buf = tree;
+
+	if (name[0] == '\0') {
+		hashcpy(sha1, root);
+		return 0;
+	}
+
+	init_tree_desc(&t, tree, size);
 	retval = find_tree_entry(&t, name, sha1, mode);
 	free(tree);
 	return retval;
 }
-