X-Git-Url: https://git.tokkee.org/?a=blobdiff_plain;f=tree-walk.c;h=8d4b67317f21508a105175686c7ec98a090ed9b5;hb=f09c9b8c5ff9d8a15499b09ccd6c3e7b3c76af77;hp=0735f4046dd8524e92e97a8ce6cc5c0991208b01;hpb=b4a081b428c607f98c5d0a0eec8d543dc1f2abcd;p=git.git

diff --git a/tree-walk.c b/tree-walk.c
index 0735f4046..8d4b67317 100644
--- a/tree-walk.c
+++ b/tree-walk.c
@@ -1,5 +1,44 @@
 #include "cache.h"
 #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)
 {
@@ -7,20 +46,19 @@ void *fill_tree_descriptor(struct tree_desc *desc, const unsigned char *sha1)
 	void *buf = NULL;
 
 	if (sha1) {
-		buf = read_object_with_reference(sha1, "tree", &size, NULL);
+		buf = read_object_with_reference(sha1, tree_type, &size, NULL);
 		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)
@@ -30,36 +68,34 @@ 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)
 {
-	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;
+	buf = end;
+	size -= len;
+	desc->buffer = buf;
+	desc->size = size;
+	if (size)
+		decode_tree_entry(desc, buf, size);
 }
 
-const unsigned char *tree_entry_extract(struct tree_desc *desc, const char **pathp, unsigned int *modep)
+int tree_entry(struct tree_desc *desc, struct name_entry *entry)
 {
-	void *tree = desc->buf;
-	unsigned long size = desc->size;
-	int len = strlen(tree)+1;
-	const unsigned char *sha1 = tree + len;
-	const char *path = strchr(tree, ' ');
-	unsigned int mode;
+	if (!desc->size)
+		return 0;
 
-	if (!path || size < len + 20 || sscanf(tree, "%o", &mode) != 1)
-		die("corrupt tree file");
-	*pathp = path+1;
-	*modep = canon_mode(mode);
-	return sha1;
+	*entry = desc->entry;
+	update_tree_entry(desc);
+	return 1;
 }
 
 void traverse_trees(int n, struct tree_desc *t, const char *base, traverse_callback_t callback)
@@ -67,7 +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;
 
@@ -114,3 +149,60 @@ void traverse_trees(int n, struct tree_desc *t, const char *base, traverse_callb
 	free(entry);
 }
 
+static int find_tree_entry(struct tree_desc *t, const char *name, unsigned char *result, unsigned *mode)
+{
+	int namelen = strlen(name);
+	while (t->size) {
+		const char *entry;
+		const unsigned char *sha1;
+		int entrylen, cmp;
+
+		sha1 = tree_entry_extract(t, &entry, mode);
+		update_tree_entry(t);
+		entrylen = tree_entry_len(entry, sha1);
+		if (entrylen > namelen)
+			continue;
+		cmp = memcmp(name, entry, entrylen);
+		if (cmp > 0)
+			continue;
+		if (cmp < 0)
+			break;
+		if (entrylen == namelen) {
+			hashcpy(result, sha1);
+			return 0;
+		}
+		if (name[entrylen] != '/')
+			continue;
+		if (!S_ISDIR(*mode))
+			break;
+		if (++entrylen == namelen) {
+			hashcpy(result, sha1);
+			return 0;
+		}
+		return get_tree_entry(sha1, name + entrylen, result, mode);
+	}
+	return -1;
+}
+
+int get_tree_entry(const unsigned char *tree_sha1, const char *name, unsigned char *sha1, unsigned *mode)
+{
+	int retval;
+	void *tree;
+	unsigned long size;
+	struct tree_desc t;
+	unsigned char root[20];
+
+	tree = read_object_with_reference(tree_sha1, tree_type, &size, root);
+	if (!tree)
+		return -1;
+
+	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;
+}