1 files changed, 91 insertions, 0 deletions
diff --git a/src/engine/e_snapshot.h b/src/engine/e_snapshot.h
new file mode 100644
index 00000000..0a74b0dc
--- /dev/null
+++ b/src/engine/e_snapshot.h
@@ -0,0 +1,91 @@
+/* copyright (c) 2007 magnus auvinen, see licence.txt for more info */
+#ifndef ENGINE_SNAPSHOT_H
+#define ENGINE_SNAPSHOT_H
+
+#include "e_system.h"
+
+/* SNAPSHOT */
+
+enum
+{
+	MAX_SNAPSHOT_SIZE=64*1024
+};
+
+typedef struct
+{
+	int type_and_id;
+} SNAPSHOT_ITEM;
+
+typedef struct 
+{
+	int data_size;
+	int num_items;
+} SNAPSHOT;
+
+int *snapitem_data(SNAPSHOT_ITEM *item);
+int snapitem_type(SNAPSHOT_ITEM *item);
+int snapitem_id(SNAPSHOT_ITEM *item);
+int snapitem_key(SNAPSHOT_ITEM *item);
+
+int *snapshot_offsets(SNAPSHOT *snap);
+char *snapshot_datastart(SNAPSHOT *snap);
+
+SNAPSHOT_ITEM *snapshot_get_item(SNAPSHOT *snap, int index);
+int snapshot_get_item_datasize(SNAPSHOT *snap, int index);
+int snapshot_get_item_index(SNAPSHOT *snap, int key);
+
+void *snapshot_empty_delta();
+int snapshot_crc(SNAPSHOT *snap);
+void snapshot_debug_dump(SNAPSHOT *snap);
+int snapshot_create_delta(SNAPSHOT *from, SNAPSHOT *to, void *data);
+int snapshot_unpack_delta(SNAPSHOT *from, SNAPSHOT *to, void *data, int data_size);
+
+/* SNAPSTORAGE */
+
+typedef struct SNAPSTORAGE_HOLDER_t
+{
+	struct SNAPSTORAGE_HOLDER_t *prev;
+	struct SNAPSTORAGE_HOLDER_t *next;
+	
+	int64 tagtime;
+	int tick;
+	
+	int snap_size;
+	SNAPSHOT *snap;
+} SNAPSTORAGE_HOLDER;
+ 
+typedef struct SNAPSTORAGE_t
+{
+	SNAPSTORAGE_HOLDER *first;
+	SNAPSTORAGE_HOLDER *last;
+} SNAPSTORAGE;
+
+void snapstorage_init(SNAPSTORAGE *ss);
+void snapstorage_purge_all(SNAPSTORAGE *ss);
+void snapstorage_purge_until(SNAPSTORAGE *ss, int tick);
+void snapstorage_add(SNAPSTORAGE *ss, int tick, int64 tagtime, int data_size, void *data);
+int snapstorage_get(SNAPSTORAGE *ss, int tick, int64 *tagtime, SNAPSHOT **data);
+
+/* SNAPBUILD */
+
+enum
+{
+	SNAPBUILD_MAX_ITEMS = 512
+};
+
+typedef struct SNAPBUILD
+{
+	char data[MAX_SNAPSHOT_SIZE];
+	int data_size;
+
+	int offsets[SNAPBUILD_MAX_ITEMS];
+	int num_items;
+} SNAPBUILD;
+
+void snapbuild_init(SNAPBUILD *sb);
+SNAPSHOT_ITEM *snapbuild_get_item(SNAPBUILD *sb, int index);
+int *snapbuild_get_item_data(SNAPBUILD *sb, int key);
+int snapbuild_finish(SNAPBUILD *sb, void *snapdata);
+void *snapbuild_new_item(SNAPBUILD *sb, int type, int id, int size);
+
+#endif /* ENGINE_SNAPSHOT_H */