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SCI: patching cleanup (+orgbyte/adjust command)

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the new commands were meant for castle/brain hangman puzzle patch, but the patch didn't work well, so I removed it. Still the commands could/should come in handy

svn-id: r52695
This commit is contained in:
Martin Kiewitz 2010-09-12 22:09:01 +00:00
parent c073369f0a
commit c447b99d4e
1 changed files with 45 additions and 9 deletions
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54
engines/sci/engine/script_patches.cpp
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@ -32,9 +32,14 @@
namespace Sci { namespace Sci {
#define PATCH_END 0xFFFF #define PATCH_END 0xFFFF
#define PATCH_ADDTOOFFSET 0x8000 #define PATCH_COMMANDMASK 0xF000
#define PATCH_GETORIGINALBYTE 0x4000 #define PATCH_VALUEMASK 0x0FFF
#define PATCH_ADDTOOFFSET 0xE000
#define PATCH_GETORIGINALBYTE 0xD000
#define PATCH_ADJUSTWORD 0xC000
#define PATCH_ADJUSTWORD_NEG 0xB000
#define PATCH_MAGICDWORD(a, b, c, d) CONSTANT_LE_32(a | (b << 8) | (c << 16) | (d << 24)) #define PATCH_MAGICDWORD(a, b, c, d) CONSTANT_LE_32(a | (b << 8) | (c << 16) | (d << 24))
#define PATCH_VALUELIMIT 4096
struct SciScriptSignature { struct SciScriptSignature {
uint16 scriptNr; uint16 scriptNr;
@ -779,17 +784,48 @@ const SciScriptSignature sq5Signatures[] = {
// will actually patch previously found signature area // will actually patch previously found signature area
void Script::applyPatch(const uint16 *patch, byte *scriptData, const uint32 scriptSize, int32 signatureOffset) { void Script::applyPatch(const uint16 *patch, byte *scriptData, const uint32 scriptSize, int32 signatureOffset) {
byte orgData[PATCH_VALUELIMIT];
int32 offset = signatureOffset; int32 offset = signatureOffset;
uint16 patchWord = *patch; uint16 patchWord = *patch;
// Copy over original bytes from script
uint32 orgDataSize = scriptSize - offset;
if (orgDataSize > PATCH_VALUELIMIT)
orgDataSize = PATCH_VALUELIMIT;
memcpy(&orgData, &scriptData[offset], orgDataSize);
while (patchWord != PATCH_END) { while (patchWord != PATCH_END) {
if (patchWord & PATCH_ADDTOOFFSET) { uint16 patchValue = patchWord & PATCH_VALUEMASK;
offset += patchWord & ~PATCH_ADDTOOFFSET; switch (patchWord & PATCH_COMMANDMASK) {
} else if (patchWord & PATCH_GETORIGINALBYTE) { case PATCH_ADDTOOFFSET:
// TODO: implement this // add value to offset
// Can be used to patch in some bytes from the original script into another location offset += patchValue & ~PATCH_ADDTOOFFSET;
} else { break;
scriptData[offset] = patchWord & 0xFF; case PATCH_GETORIGINALBYTE:
// get original byte from script
if (patchValue >= orgDataSize)
error("patching: can not get requested original byte from script");
scriptData[offset] = orgData[patchValue];
offset++;
break;
case PATCH_ADJUSTWORD: {
// Adjust word right before current position
byte *adjustPtr = &scriptData[offset - 2];
uint16 adjustWord = READ_LE_UINT16(adjustPtr);
adjustWord += patchValue;
WRITE_LE_UINT16(adjustPtr, adjustWord);
break;
}
case PATCH_ADJUSTWORD_NEG: {
// Adjust word right before current position (negative way)
byte *adjustPtr = &scriptData[offset - 2];
uint16 adjustWord = READ_LE_UINT16(adjustPtr);
adjustWord -= patchValue;
WRITE_LE_UINT16(adjustPtr, adjustWord);
break;
}
default:
scriptData[offset] = patchValue & 0xFF;
offset++; offset++;
} }
patch++; patch++;