SCI: script patcher is now a separate class

1 files changed, 100 insertions, 0 deletions

diff --git a/engines/sci/engine/script_patches.h b/engines/sci/engine/script_patches.h
new file mode 100644
index 0000000000..77cb2c7ef1
--- /dev/null
+++ b/engines/sci/engine/script_patches.h
@@ -0,0 +1,100 @@
+/* ScummVM - Graphic Adventure Engine
+ *
+ * ScummVM is the legal property of its developers, whose names
+ * are too numerous to list here. Please refer to the COPYRIGHT
+ * file distributed with this source distribution.
+ *
+ * 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.
+ *
+ */
+
+#ifndef SCI_ENGINE_SCRIPT_PATCHES_H
+#define SCI_ENGINE_SCRIPT_PATCHES_H
+
+#include "sci/sci.h"
+
+namespace Sci {
+
+#define SIG_END               0xFFFF
+#define SIG_MISMATCH          0xFFFE
+#define SIG_COMMANDMASK       0xF000
+#define SIG_VALUEMASK         0x0FFF
+#define SIG_BYTEMASK          0x00FF
+#define SIG_MAGICDWORD        0xF000
+#define SIG_ADDTOOFFSET       0xE000
+#define SIG_SELECTOR16        0x9000
+#define SIG_SELECTOR8         0x8000
+#define SIG_UINT16            0x1000
+#define SIG_BYTE              0x0000
+
+#define PATCH_END                   SIG_END
+#define PATCH_COMMANDMASK           SIG_COMMANDMASK
+#define PATCH_VALUEMASK             SIG_VALUEMASK
+#define PATCH_BYTEMASK              SIG_BYTEMASK
+#define PATCH_ADDTOOFFSET           SIG_ADDTOOFFSET
+#define PATCH_GETORIGINALBYTE       0xD000
+#define PATCH_GETORIGINALBYTEADJUST 0xC000
+#define PATCH_SELECTOR16            SIG_SELECTOR16
+#define PATCH_SELECTOR8             SIG_SELECTOR8
+#define PATCH_UINT16                SIG_UINT16
+#define PATCH_BYTE                  SIG_BYTE
+
+// defines maximum scratch area for getting original bytes from unpatched script data
+#define PATCH_VALUELIMIT      4096
+
+struct SciScriptPatcherEntry {
+	bool defaultActive;
+//	bool active;
+	uint16 scriptNr;
+	const char *description;
+	int16 applyCount;
+//	uint32 magicDWord;
+//	int magicOffset;
+	const uint16 *signatureData;
+	const uint16 *patchData;
+};
+
+//#define SCI_SIGNATUREENTRY_TERMINATOR { false, 0, NULL, 0, 0, 0, NULL, NULL }
+#define SCI_SIGNATUREENTRY_TERMINATOR { false, 0, NULL, 0, NULL, NULL }
+
+struct SciScriptPatcherRuntimeEntry {
+	bool active;
+	uint32 magicDWord;
+	int magicOffset;
+};
+
+/**
+ * ScriptPatcher class, handles on-the-fly patching of script data
+ */
+class ScriptPatcher {
+public:
+	ScriptPatcher();
+	~ScriptPatcher();
+
+	void processScript(uint16 scriptNr, byte *scriptData, const uint32 scriptSize);
+
+private:
+	void initSignature(SciScriptPatcherEntry *patchTable, bool isMacSci11);
+	void enablePatch(SciScriptPatcherEntry *patchTable, const char *searchDescription);
+	int32 findSignature(const SciScriptPatcherEntry *patchEntry, SciScriptPatcherRuntimeEntry *runtimeEntry, const byte *scriptData, const uint32 scriptSize, bool isMacSci11);
+	void applyPatch(const SciScriptPatcherEntry *patchEntry, byte *scriptData, const uint32 scriptSize, int32 signatureOffset, bool isMacSci11);
+	
+	Selector *_selectorIdTable;
+	SciScriptPatcherRuntimeEntry *_runtimeTable;
+};
+
+} // End of namespace Sci
+
+#endif // SCI_ENGINE_WORKAROUNDS_H