ErrorCode PTrace::step(ProcessThreadId const &ptid, ProcessInfo const &pinfo,
int signal, Address const &address) {
pid_t pid;
if (!ptid.valid())
return kErrorInvalidArgument;
if (!(ptid.tid <= kAnyThreadId)) {
pid = ptid.tid;
} else {
pid = ptid.pid;
}
//
// Continuation from address?
//
if (address.valid()) {
Architecture::CPUState state;
ErrorCode error = readCPUState(ptid, pinfo, state);
if (error != kSuccess)
return error;
state.setPC(address);
error = writeCPUState(ptid, pinfo, state);
if (error != kSuccess)
return error;
}
// (caddr_t)1 indicate that execution is to pick up where it left off.
if (wrapPtrace(PT_STEP, pid, (caddr_t)1, signal) < 0)
return Platform::TranslateError();
return kSuccess;
}
ErrorCode PTrace::prepareAddressForResume(ProcessThreadId const &ptid,
ProcessInfo const &pinfo,
Address const &address) {
if (address.valid()) {
Architecture::CPUState state;
ErrorCode error = readCPUState(ptid, pinfo, state);
if (error != kSuccess) {
return error;
}
state.setPC(address);
error = writeCPUState(ptid, pinfo, state);
if (error != kSuccess) {
return error;
}
}
return kSuccess;
}