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diff --git a/engines/scumm/saveload.h b/engines/scumm/saveload.h
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+/* ScummVM - Scumm Interpreter
+ * Copyright (C) 2002-2006 The ScummVM project
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ * $URL$
+ * $Id$
+ *
+ */
+
+#ifndef SAVELOAD_H
+#define SAVELOAD_H
+
+#include "common/scummsys.h"
+
+namespace Common {
+	class InSaveFile;
+	class OutSaveFile;
+}
+
+namespace Scumm {
+
+
+/**
+ * The current savegame format version.
+ * Our save/load system uses an elaborate scheme to allow us to modify the
+ * savegame while keeping full backward compatibility, in the sense that newer
+ * ScummVM versions always are able to load old savegames.
+ * In order to achieve that, we store a version in the savegame files, and whenever
+ * the savegame layout is modified, the version is incremented.
+ *
+ * This roughly works by marking each savegame entry with a range of versions
+ * for which it is valid; the save/load code iterates over all entries, but
+ * only saves/loads those which are valid for the version of the savegame
+ * which is being loaded/saved currently.
+ */
+#define CURRENT_VER 64
+
+/**
+ * An auxillary macro, used to specify savegame versions. We use this instead
+ * of just writing the raw version, because this way they stand out more to
+ * the reading eye, making it a bit easier to navigate through the code.
+ */
+#define VER(x) x
+
+
+/**
+ * The OFFS macro essentially provides the functionality of offsetof(), that
+ * is, it determines the offset of a struct/class member within instances of
+ * that class.
+ *
+ * This is a place where we cheat a bit and sacrifice some potential portability
+ * (although so far we haven't encountered any platform where this matters).
+ *
+ * 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 have a heuristic built in to detect "offset-of" patterns - which is exactly
+ * what our OFFS macro does. Now, for non-POD types this is not really legal, because
+ * member need not be at a fixed offset relative to the variable, even if they are in
+ * current reality (many of our complex structs are non-POD; for an explanation of
+ * what POD means refer to http://www-cpd.fnal.gov/personal/wb/boost/ISOcxx/doc/POD.html)
+ */
+#define OFFS(type,item) (((long)(&((type*)42)->type::item))-42)
+
+/**
+ * Similar to the OFFS macro, this macro computes the size (in bytes) of a
+ * member of a given struct/class type.
+ */
+#define SIZE(type,item) sizeof(((type*)42)->type::item)
+
+// 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,dim,minVer) {OFFS(type,item),128|saveas,SIZE(type,item),minVer,CURRENT_VER}, {dim,1,0,0,0}
+#define MKARRAY2(type,item,saveas,dim,dim2,rowlen,minVer) {OFFS(type,item),128|saveas,SIZE(type,item),minVer,CURRENT_VER}, {dim,dim2,rowlen,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,dim,minVer,maxVer) {OFFS(type,item),128|saveas,SIZE(type,item),minVer,maxVer}, {dim,1,0,0,0}
+#define MKARRAY2_OLD(type,item,saveas,dim,dim2,rowlen,minVer,maxVer) {OFFS(type,item),128|saveas,SIZE(type,item),minVer,maxVer}, {dim,dim2,rowlen,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,dim,minVer,maxVer) {0,128|saveas,0,minVer,maxVer}, {dim,1,0,0,0}
+#define MK_OBSOLETE_ARRAY2(type,item,saveas,dim,dim2,rowlen,minVer,maxVer) {0,128|saveas,0,minVer,maxVer}, {dim,dim2,rowlen,0,0}
+
+// End marker
+#define MKEND() {0xFFFF,0xFF,0xFF,0,0}
+
+
+enum {
+	sleByte = 1,
+	sleUint8 = 1,
+	sleInt8 = 1,
+	sleInt16 = 2,
+	sleUint16 = 3,
+	sleInt32 = 4,
+	sleUint32 = 5
+};
+
+struct SaveLoadEntry {
+	uint32 offs;	// or: array dimension
+	uint16 type;	// or: array dimension 2
+	uint16 size;	// or: array row length
+	uint8 minVersion;
+	uint8 maxVersion;
+};
+
+class Serializer {
+public:
+	Serializer(Common::InSaveFile *in, Common::OutSaveFile *out, uint32 savegameVersion)
+		: _loadStream(in), _saveStream(out),
+		  _savegameVersion(savegameVersion)
+	{ }
+
+	void saveLoadArrayOf(void *b, int len, int datasize, byte filetype);
+	void saveLoadArrayOf(void *b, int num, int datasize, const SaveLoadEntry *sle);
+	void saveLoadEntries(void *d, const SaveLoadEntry *sle);
+
+	bool isSaving() { return (_saveStream != 0); }
+	bool isLoading() { return (_loadStream != 0); }
+	uint32 getVersion() { return _savegameVersion; }
+
+	void saveUint32(uint32 d);
+	void saveUint16(uint16 d);
+	void saveByte(byte b);
+
+	byte loadByte();
+	uint16 loadUint16();
+	uint32 loadUint32();
+
+	void saveBytes(void *b, int len);
+	void loadBytes(void *b, int len);
+
+protected:
+	Common::InSaveFile *_loadStream;
+	Common::OutSaveFile *_saveStream;
+	uint32 _savegameVersion;
+
+	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);
+};
+
+
+// Mixin class / interface. Maybe call it ISerializable or SerializableMixin ?
+class Serializable {
+public:
+	virtual ~Serializable() {}
+	virtual void saveLoadWithSerializer(Serializer *ser) = 0;
+};
+
+} // End of namespace Scumm
+
+#endif