libretro/scummvm
1
0
Fork 0
mirror of https://github.com/libretro/scummvm.git synced 2025-03-06 02:10:28 +00:00
Code Issues Actions Packages Projects Releases Wiki Activity

SCI: Switch GameFeatures::autoDetectFeature to using readPMachineInstruction

Browse Source 
svn-id: r47959
This commit is contained in:
Max Horn 2010-02-07 12:15:12 +00:00
parent 4cfcf57546
commit f3ef11cdc5
1 changed files with 20 additions and 74 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

94
engines/sci/engine/features.cpp
View File

@ -102,27 +102,22 @@ bool GameFeatures::autoDetectFeature(FeatureDetection featureDetection, int meth
uint16 intParam = 0xFFFF;
do {
uint16 kFuncNum;
int opsize = script->_buf[offset++];
uint opcode = opsize >> 1;
int i = 0;
byte argc;
int16 opparams[4];
byte opsize;
offset += readPMachineInstruction(script->_buf + offset, opsize, opparams);
const byte opcode = opsize >> 1;
if (opcode == op_ret)
break;
if (featureDetection == kDetectLofsType) {
if (opcode == op_lofsa || opcode == op_lofss) {
uint16 lofs;
// Load lofs operand
if (opsize & 1) {
if (offset >= script->_bufSize)
break;
lofs = script->_buf[offset++];
} else {
if ((uint32)offset + 1 >= (uint32)script->_bufSize)
break;
lofs = READ_LE_UINT16(script->_buf + offset);
offset += 2;
}
uint16 lofs = opparams[0];
// Sanity check
if (offset >= script->_bufSize)
break;
// Check for going out of bounds when interpreting as abs/rel
if (lofs >= script->_bufSize)
@ -137,10 +132,8 @@ bool GameFeatures::autoDetectFeature(FeatureDetection featureDetection, int meth
if (_lofsType != SCI_VERSION_NONE)
return true;
// If we reach here, we haven't been able to deduce the lofs parameter
// type, but we have advanced the offset pointer already. So move on
// to the next opcode
continue;
// If we reach here, we haven't been able to deduce the lofs
// parameter type.
}
}
@ -151,49 +144,17 @@ bool GameFeatures::autoDetectFeature(FeatureDetection featureDetection, int meth
// of the sound commands has changed at some point during SCI1 middle
if (opcode == op_pushi) {
// Load the pushi parameter
if (opsize & 1) {
if (offset >= script->_bufSize)
break;
intParam = script->_buf[offset++];
} else {
if ((uint32)offset + 1 >= (uint32)script->_bufSize)
break;
intParam = READ_LE_UINT16(script->_buf + offset);
offset += 2;
}
intParam = opparams[0];
continue;
// Sanity check
if (offset >= script->_bufSize)
break;
}
}
while (g_opcode_formats[opcode][i]) {
switch (g_opcode_formats[opcode][i++]) {
case Script_Invalid:
break;
case Script_SByte:
case Script_Byte:
offset++;
break;
case Script_Word:
case Script_SWord:
offset += 2;
break;
case Script_SVariable:
case Script_Variable:
case Script_Property:
case Script_Global:
case Script_Local:
case Script_Temp:
case Script_Param:
if (opsize & 1)
kFuncNum = script->_buf[offset++];
else {
kFuncNum = 0xffff & (script->_buf[offset] | (script->_buf[offset + 1] << 8));
offset += 2;
}
if (opcode == op_callk) {
argc = script->_buf[offset++];
uint16 kFuncNum = opparams[0];
uint16 argc = opparams[1];
switch (featureDetection) {
case kDetectGfxFunctions:
@ -259,22 +220,7 @@ bool GameFeatures::autoDetectFeature(FeatureDetection featureDetection, int meth
break;
}
}
break;
case Script_Offset:
case Script_SRelative:
offset++;
if (!opsize & 1)
offset++;
break;
case Script_End:
offset = 0; // exit loop
break;
default:
warning("opcode %02x: Invalid", opcode);
}
}
} while (offset > 0);
return false; // not found