void IDkmLanguageConditionEvaluator.EvaluateCondition(DkmEvaluationBreakpointCondition evaluationCondition, DkmStackWalkFrame stackFrame, out bool stop, out string errorText)
{
DkmProcess process = stackFrame.Process;
var processData = DebugHelpers.GetOrCreateDataItem <LuaRemoteProcessData>(process);
if (processData.locations == null)
{
stop = true;
errorText = "Debug helper data for conditional breakpoint is missing";
return;
}
DkmInspectionSession inspectionSession = DkmInspectionSession.Create(process, null);
ulong stateAddress = DebugHelpers.ReadPointerVariable(process, processData.locations.helperBreakHitLuaStateAddress).GetValueOrDefault(0);
if (stateAddress == 0)
{
inspectionSession.Close();
stop = true;
errorText = "Failed to evaluate current Lua state address";
return;
}
ulong callInfoAddress = 0;
// Read lua_State
ulong temp = stateAddress;
ulong?savedProgramCounterAddress = null;
// CommonHeader
DebugHelpers.SkipStructPointer(process, ref temp);
DebugHelpers.SkipStructByte(process, ref temp);
DebugHelpers.SkipStructByte(process, ref temp);
if (processData.luaVersion == 501)
{
DebugHelpers.SkipStructByte(process, ref temp); // status
DebugHelpers.SkipStructPointer(process, ref temp); // top
DebugHelpers.SkipStructPointer(process, ref temp); // base
DebugHelpers.SkipStructPointer(process, ref temp); // l_G
callInfoAddress = DebugHelpers.ReadStructPointer(process, ref temp).GetValueOrDefault(0);
savedProgramCounterAddress = DebugHelpers.ReadStructPointer(process, ref temp).GetValueOrDefault(0);
}
else if (processData.luaVersion == 502)
{
DebugHelpers.SkipStructByte(process, ref temp); // status
DebugHelpers.SkipStructPointer(process, ref temp); // top
DebugHelpers.SkipStructPointer(process, ref temp); // l_G
callInfoAddress = DebugHelpers.ReadStructPointer(process, ref temp).GetValueOrDefault(0);
}
else if (processData.luaVersion == 503)
{
DebugHelpers.SkipStructShort(process, ref temp); // nci
DebugHelpers.SkipStructByte(process, ref temp); // status
DebugHelpers.SkipStructPointer(process, ref temp); // top
DebugHelpers.SkipStructPointer(process, ref temp); // l_G
callInfoAddress = DebugHelpers.ReadStructPointer(process, ref temp).GetValueOrDefault(0);
}
else if (processData.luaVersion == 504)
{
DebugHelpers.SkipStructByte(process, ref temp); // status
DebugHelpers.SkipStructByte(process, ref temp); // allowhook
DebugHelpers.SkipStructShort(process, ref temp); // nci
DebugHelpers.SkipStructPointer(process, ref temp); // top
DebugHelpers.SkipStructPointer(process, ref temp); // l_G
callInfoAddress = DebugHelpers.ReadStructPointer(process, ref temp).GetValueOrDefault(0);
}
if (callInfoAddress == 0)
{
inspectionSession.Close();
stop = true;
errorText = $"Failed to evaluate current Lua call frame (Lua version {processData.luaVersion})";
return;
}
// Load call info data (to get base stack address)
LuaFunctionCallInfoData callInfoData = new LuaFunctionCallInfoData();
callInfoData.ReadFrom(process, callInfoAddress); // TODO: cache?
callInfoData.ReadFunction(process);
if (callInfoData.func == null)
{
inspectionSession.Close();
stop = true;
errorText = $"Failed to evaluate current Lua call frame function (Lua version {processData.luaVersion})";
return;
}
if (callInfoData.func.extendedType != LuaExtendedType.LuaFunction)
{
inspectionSession.Close();
stop = true;
errorText = "Breakpoint location has to be inside a Lua function";
return;
}
LuaValueDataLuaFunction currCallLuaFunction = callInfoData.func as LuaValueDataLuaFunction;
LuaClosureData closureData = currCallLuaFunction.value;
LuaFunctionData functionData = null;
if (processData.functionDataCache.ContainsKey(closureData.functionAddress))
{
functionData = processData.functionDataCache[closureData.functionAddress];
}
else
{
functionData = closureData.ReadFunction(process);
functionData.ReadUpvalues(process);
functionData.ReadLocals(process, -1);
processData.functionDataCache.Add(closureData.functionAddress, functionData);
}
if (!savedProgramCounterAddress.HasValue)
{
savedProgramCounterAddress = callInfoData.savedInstructionPointerAddress;
}
// Possible in bad break locations
if (savedProgramCounterAddress < functionData.codeDataAddress)
{
inspectionSession.Close();
stop = true;
errorText = "Invalid saved program counter";
return;
}
long currInstructionPointer = ((long)savedProgramCounterAddress - (long)functionData.codeDataAddress) / 4; // unsigned size instructions
// If the call was already made, savedpc will be offset by 1 (return location)
int prevInstructionPointer = currInstructionPointer == 0 ? 0 : (int)currInstructionPointer - 1;
functionData.UpdateLocals(process, prevInstructionPointer);
ExpressionEvaluation evaluation = new ExpressionEvaluation(process, functionData, callInfoData.stackBaseAddress, closureData);
var result = evaluation.Evaluate(evaluationCondition.Source.Text);
if (result as LuaValueDataError != null)
{
var resultAsError = result as LuaValueDataError;
inspectionSession.Close();
stop = true;
errorText = resultAsError.value;
return;
}
if (result.baseType == LuaBaseType.Nil)
{
inspectionSession.Close();
stop = false;
errorText = null;
return;
}
if (result is LuaValueDataBool resultBool)
{
inspectionSession.Close();
stop = resultBool.value;
errorText = null;
return;
}
var resultNumber = result as LuaValueDataNumber;
if (resultNumber == null)
{
inspectionSession.Close();
stop = true;
errorText = $"Value can't be used as condition: {result.AsSimpleDisplayString(10)}";
return;
}
inspectionSession.Close();
stop = resultNumber.value != 0.0;
errorText = null;
}
void IDkmLanguageConditionEvaluator.ParseCondition(DkmEvaluationBreakpointCondition evaluationCondition, out string errorText)
{
// This place could be used to typecheck of pre-compile the expression
errorText = null;
}
