X-Git-Url: https://git.octo.it/?a=blobdiff_plain;f=delta.h;h=31d1820f80f2887d51808170fc86585ada42d42e;hb=794f9fe7db30e2aff8f8f0543c6d18bf579cdbc2;hp=ccc0c9ecebfa160f1f33ce3285deaa3557814941;hpb=75c42d8cc3b42e4b82946848b8ba902b4bbcc38d;p=git.git

diff --git a/delta.h b/delta.h
index ccc0c9ec..31d1820f 100644
--- a/delta.h
+++ b/delta.h
@@ -9,13 +9,26 @@ extern void *patch_delta(void *src_buf, unsigned long src_size,
 			 void *delta_buf, unsigned long delta_size,
 			 unsigned long *dst_size);
 
-/* handling of delta objects */
-struct delta;
-struct object_list;
-extern struct delta *lookup_delta(const unsigned char *sha1);
-extern int parse_delta_buffer(struct delta *item, void *buffer, unsigned long size);
-extern int parse_delta(struct delta *item, unsigned char sha1);
-extern int process_deltas(void *src, unsigned long src_size,
-			  const char *src_type, struct object_list *delta);
+/* the smallest possible delta size is 4 bytes */
+#define DELTA_SIZE_MIN	4
+
+/*
+ * This must be called twice on the delta data buffer, first to get the
+ * expected reference buffer size, and again to get the result buffer size.
+ */
+static inline unsigned long get_delta_hdr_size(const unsigned char **datap)
+{
+	const unsigned char *data = *datap;
+	unsigned char cmd = *data++;
+	unsigned long size = cmd & ~0x80;
+	int i = 7;
+	while (cmd & 0x80) {
+		cmd = *data++;
+		size |= (cmd & ~0x80) << i;
+		i += 7;
+	}
+	*datap = data;
+	return size;
+}
 
 #endif