1 files changed, 60 insertions, 19 deletions

diff --git a/scumm/saveload.h b/scumm/saveload.h
index 914d6b9346..1667aeb045 100644
--- a/scumm/saveload.h
+++ b/scumm/saveload.h
@@ -22,6 +22,17 @@
 #ifndef SAVELOAD_H
 #define SAVELOAD_H
 
+// Support for "old" savegames (made with 2501 CVS build)
+// Can be useful for other ports too :)
+
+#define VER_V10 10
+#define VER_V9 9
+#define VER_V8 8
+#define VER_V7 7
+
+#define CURRENT_VER VER_V10
+
+
 // To work around a warning in GCC 3.2 (and 3.1 ?) regarding non-POD types,
 // we use a small trick: instead of 0 we use 42. Why? Well, it seems newer GCC
 // versions hae a heuristic built in to detect "offset-of" patterns - which is exactly
@@ -32,11 +43,29 @@
 
 #define OFFS(type,item) (((int)(&((type*)42)->type::item))-42)
 #define SIZE(type,item) sizeof(((type*)42)->type::item)
-#define MKLINE(type,item,saveas) {OFFS(type,item),saveas,SIZE(type,item)}
-#define MKARRAY(type,item,saveas,num) {OFFS(type,item),128|saveas,SIZE(type,item)}, {num,0,0}
-#define MKEND() {0xFFFF,0xFF,0xFF}
 
-#define MKREF(type,item,refid) {OFFS(type,item),refid,0xFF}
+// Any item that is still in use automatically gets a maxVersion equal to CURRENT_VER
+#define MKLINE(type,item,saveas,minVer) {OFFS(type,item),saveas,SIZE(type,item),minVer,CURRENT_VER}
+#define MKARRAY(type,item,saveas,num,minVer) {OFFS(type,item),128|saveas,SIZE(type,item),minVer,CURRENT_VER}, {num,0,0,0,0}
+
+// Use this if you have an entry that used to be smaller:
+#define MKLINE_OLD(type,item,saveas,minVer,maxVer) {OFFS(type,item),saveas,SIZE(type,item),minVer,maxVer}
+#define MKARRAY_OLD(type,item,saveas,num,minVer,maxVer) {OFFS(type,item),128|saveas,SIZE(type,item),minVer,maxVer}, {num,0,0,0,0}
+
+// An obsolete item/array, to be ignored upon load. We retain the type/item params to make it easier to debug.
+// Obsolete items have size == 0.
+#define MK_OBSOLETE(type,item,saveas,minVer,maxVer) {0,saveas,0,minVer,maxVer}
+#define MK_OBSOLETE_ARRAY(type,item,saveas,num,minVer,maxVer) {0,128|saveas,0,minVer,maxVer}, {num,0,0,0,0}
+
+// End marker
+#define MKEND() {0xFFFF,0xFF,0xFF,0,0}
+
+// A reference
+#define MKREF(type,item,refid,minVer) {OFFS(type,item),refid,0xFF,minVer,CURRENT_VER}
+
+// An obsolete reference.
+#define MK_OBSOLETE_REF(type,item,refid,minVer,maxVer) {0,sleUint16,0,minVer,maxVer}
+
 
 enum {
 	sleByte = 1,
@@ -52,6 +81,8 @@ struct SaveLoadEntry {
 	uint32 offs;
 	uint8 type;
 	uint8 size;
+	uint8 minVersion;
+	uint8 maxVersion;
 };
 
 struct SerializerStream {
@@ -83,24 +114,25 @@ struct SerializerStream {
 typedef int SerializerSaveReference(void *me, byte type, void *ref);
 typedef void *SerializerLoadReference(void *me, byte type, int ref);
 
-struct Serializer {
-	SerializerStream _saveLoadStream;
+class Serializer {
+public:
+	Serializer(SerializerStream stream, bool saveOrLoad, uint32 savegameVersion)
+		: _save_ref(0), _load_ref(0), _ref_me(0),
+		  _saveLoadStream(stream), _saveOrLoad(saveOrLoad),
+		  _savegameVersion(savegameVersion)
+	{ }
 
-	union {
-		SerializerSaveReference *_save_ref;
-		SerializerLoadReference *_load_ref;
-		void *_saveload_ref;
-	};
+	SerializerSaveReference *_save_ref;
+	SerializerLoadReference *_load_ref;
 	void *_ref_me;
 
-	bool _saveOrLoad;
-
-	void saveBytes(void *b, int len);
-	void loadBytes(void *b, int len);
-	
 	void saveLoadArrayOf(void *b, int len, int datasize, byte filetype);
-	void saveLoadEntries(void *d, const SaveLoadEntry *sle);
 	void saveLoadArrayOf(void *b, int num, int datasize, const SaveLoadEntry *sle);
+	void saveLoadEntries(void *d, const SaveLoadEntry *sle);
+
+	bool isSaving() { return _saveOrLoad; }
+
+	bool checkEOFLoadStream();
 
 	void saveUint32(uint32 d);
 	void saveWord(uint16 d);
@@ -110,10 +142,19 @@ struct Serializer {
 	uint16 loadWord();
 	uint32 loadUint32();
 
-	bool isSaving() { return _saveOrLoad; }
+	void saveBytes(void *b, int len);
+	void loadBytes(void *b, int len);
+	
+protected:
+	SerializerStream _saveLoadStream;
+	bool _saveOrLoad;
+	uint32 _savegameVersion;
 
-	bool checkEOFLoadStream();
+	void saveArrayOf(void *b, int len, int datasize, byte filetype);
+	void loadArrayOf(void *b, int len, int datasize, byte filetype);
 
+	void saveEntries(void *d, const SaveLoadEntry *sle);
+	void loadEntries(void *d, const SaveLoadEntry *sle);
 };
 
 #endif