diff options
Diffstat (limited to 'engines/sci/engine/script_patches.h')
| -rw-r--r-- | engines/sci/engine/script_patches.h | 109 |
1 files changed, 109 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..d15fce321b --- /dev/null +++ b/engines/sci/engine/script_patches.h @@ -0,0 +1,109 @@ +/* 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 { + +// Please do not use the #defines, that are called SIG_CODE_* / PATCH_CODE_* inside signature/patch-tables +#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_CODE_ADDTOOFFSET 0xE000 +#define SIG_ADDTOOFFSET(_offset_) SIG_CODE_ADDTOOFFSET | _offset_ +#define SIG_CODE_SELECTOR16 0x9000 +#define SIG_SELECTOR16(_selectorID_) SIG_CODE_SELECTOR16 | SELECTOR_##_selectorID_ +#define SIG_CODE_SELECTOR8 0x8000 +#define SIG_SELECTOR8(_selectorID_) SIG_CODE_SELECTOR8 | SELECTOR_##_selectorID_ +#define SIG_CODE_UINT16 0x1000 +#define SIG_UINT16(_value_) SIG_CODE_UINT16 | (_value_ & 0xFF), (_value_ >> 8) +#define SIG_CODE_BYTE 0x0000 + +#define PATCH_END SIG_END +#define PATCH_COMMANDMASK SIG_COMMANDMASK +#define PATCH_VALUEMASK SIG_VALUEMASK +#define PATCH_BYTEMASK SIG_BYTEMASK +#define PATCH_CODE_ADDTOOFFSET SIG_CODE_ADDTOOFFSET +#define PATCH_ADDTOOFFSET(_offset_) SIG_CODE_ADDTOOFFSET | _offset_ +#define PATCH_CODE_GETORIGINALBYTE 0xD000 +#define PATCH_GETORIGINALBYTE(_offset_) PATCH_CODE_GETORIGINALBYTE | _offset_ +#define PATCH_CODE_GETORIGINALBYTEADJUST 0xC000 +#define PATCH_GETORIGINALBYTEADJUST(_offset_, _adjustValue_) PATCH_CODE_GETORIGINALBYTEADJUST | _offset_, (uint16)(_adjustValue_) +#define PATCH_CODE_SELECTOR16 SIG_CODE_SELECTOR16 +#define PATCH_SELECTOR16(_selectorID_) SIG_CODE_SELECTOR16 | SELECTOR_##_selectorID_ +#define PATCH_CODE_SELECTOR8 SIG_CODE_SELECTOR8 +#define PATCH_SELECTOR8(_selectorID_) SIG_CODE_SELECTOR8 | SELECTOR_##_selectorID_ +#define PATCH_CODE_UINT16 SIG_CODE_UINT16 +#define PATCH_UINT16(_value_) SIG_CODE_UINT16 | (_value_ & 0xFF), (_value_ >> 8) +#define PATCH_CODE_BYTE SIG_CODE_BYTE + +// defines maximum scratch area for getting original bytes from unpatched script data +#define PATCH_VALUELIMIT 4096 + +struct SciScriptPatcherEntry { + bool defaultActive; + uint16 scriptNr; + const char *description; + int16 applyCount; + const uint16 *signatureData; + const uint16 *patchData; +}; + +#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); + bool verifySignature(uint32 byteOffset, const uint16 *signatureData, const char *signatureDescription, const byte *scriptData, const uint32 scriptSize); + +private: + void initSignature(const SciScriptPatcherEntry *patchTable); + void enablePatch(const SciScriptPatcherEntry *patchTable, const char *searchDescription); + int32 findSignature(const SciScriptPatcherEntry *patchEntry, SciScriptPatcherRuntimeEntry *runtimeEntry, const byte *scriptData, const uint32 scriptSize); + void applyPatch(const SciScriptPatcherEntry *patchEntry, byte *scriptData, const uint32 scriptSize, int32 signatureOffset); + + Selector *_selectorIdTable; + SciScriptPatcherRuntimeEntry *_runtimeTable; + bool _isMacSci11; +}; + +} // End of namespace Sci + +#endif // SCI_ENGINE_WORKAROUNDS_H |