ErrorCode Thread::step(int signal, Address const &address) {
// Windows doesn't have a dedicated single-step call. We have to set the
// single step flag (TF, 8th bit) in eflags and resume the thread.
ErrorCode error = modifyRegisters(
[](Architecture::CPUState &state) { state.gp.eflags |= (1 << 8); });
if (error != kSuccess) {
return error;
}
return resume(signal, address);
}
ErrorCode Thread::resume(int signal, Address const &address) {
// TODO(sas): Not sure how to translate the signal concept to Windows yet.
// We'll probably have to get rid of these at some point.
DS2ASSERT(signal == 0);
if (address.valid()) {
CHK(modifyRegisters(
[&address](Architecture::CPUState &state) { state.setPC(address); }));
}
switch (_state) {
case kInvalid:
case kRunning:
DS2BUG("trying to suspend tid %" PRI_PID " in state %s", tid(),
Stringify::ThreadState(_state));
break;
case kTerminated:
return kErrorProcessNotFound;
case kStopped:
case kStepped: {
if (_stopInfo.event == StopInfo::kEventStop &&
_stopInfo.reason == StopInfo::kReasonNone) {
DWORD result = ::ResumeThread(_handle);
if (result == (DWORD)-1) {
return Platform::TranslateError();
}
} else {
BOOL result = ::ContinueDebugEvent(_process->pid(), _tid, DBG_CONTINUE);
if (!result) {
return Platform::TranslateError();
}
}
_state = kRunning;
return kSuccess;
}
}
// Silence warnings without using a `default:` case for the above switch.
DS2_UNREACHABLE();
}
