diff options
| -rw-r--r-- | engines/sci/engine/features.cpp | 94 |
1 files changed, 20 insertions, 74 deletions
diff --git a/engines/sci/engine/features.cpp b/engines/sci/engine/features.cpp index 736a125b88..cce67fb85a 100644 --- a/engines/sci/engine/features.cpp +++ b/engines/sci/engine/features.cpp @@ -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 |