size_t
Communication::Read (void *dst, size_t dst_len, uint32_t timeout_usec, ConnectionStatus &status, Error *error_ptr)
{
lldb_private::LogIfAnyCategoriesSet (LIBLLDB_LOG_COMMUNICATION,
"%p Communication::Read (dst = %p, dst_len = %" PRIu64 ", timeout = %u usec) connection = %p",
this,
dst,
(uint64_t)dst_len,
timeout_usec,
m_connection_sp.get());
if (m_read_thread_enabled)
{
// We have a dedicated read thread that is getting data for us
size_t cached_bytes = GetCachedBytes (dst, dst_len);
if (cached_bytes > 0 || timeout_usec == 0)
{
status = eConnectionStatusSuccess;
return cached_bytes;
}
if (m_connection_sp.get() == NULL)
{
if (error_ptr)
error_ptr->SetErrorString("Invalid connection.");
status = eConnectionStatusNoConnection;
return 0;
}
// Set the timeout appropriately
TimeValue timeout_time;
if (timeout_usec != UINT32_MAX)
{
timeout_time = TimeValue::Now();
timeout_time.OffsetWithMicroSeconds (timeout_usec);
}
Listener listener ("Communication::Read");
listener.StartListeningForEvents (this, eBroadcastBitReadThreadGotBytes | eBroadcastBitReadThreadDidExit);
EventSP event_sp;
while (listener.WaitForEvent (timeout_time.IsValid() ? &timeout_time : NULL, event_sp))
{
const uint32_t event_type = event_sp->GetType();
if (event_type & eBroadcastBitReadThreadGotBytes)
{
return GetCachedBytes (dst, dst_len);
}
if (event_type & eBroadcastBitReadThreadDidExit)
{
Disconnect (NULL);
break;
}
}
return 0;
}
// We aren't using a read thread, just read the data synchronously in this
// thread.
lldb::ConnectionSP connection_sp (m_connection_sp);
if (connection_sp.get())
{
return connection_sp->Read (dst, dst_len, timeout_usec, status, error_ptr);
}
if (error_ptr)
error_ptr->SetErrorString("Invalid connection.");
status = eConnectionStatusNoConnection;
return 0;
}
void *
ProcessKDP::AsyncThread (void *arg)
{
ProcessKDP *process = (ProcessKDP*) arg;
const lldb::pid_t pid = process->GetID();
Log *log (ProcessKDPLog::GetLogIfAllCategoriesSet (KDP_LOG_PROCESS));
if (log)
log->Printf ("ProcessKDP::AsyncThread (arg = %p, pid = %" PRIu64 ") thread starting...", arg, pid);
Listener listener ("ProcessKDP::AsyncThread");
EventSP event_sp;
const uint32_t desired_event_mask = eBroadcastBitAsyncContinue |
eBroadcastBitAsyncThreadShouldExit;
if (listener.StartListeningForEvents (&process->m_async_broadcaster, desired_event_mask) == desired_event_mask)
{
bool done = false;
while (!done)
{
if (log)
log->Printf ("ProcessKDP::AsyncThread (pid = %" PRIu64 ") listener.WaitForEvent (NULL, event_sp)...",
pid);
if (listener.WaitForEvent (NULL, event_sp))
{
uint32_t event_type = event_sp->GetType();
if (log)
log->Printf ("ProcessKDP::AsyncThread (pid = %" PRIu64 ") Got an event of type: %d...",
pid,
event_type);
// When we are running, poll for 1 second to try and get an exception
// to indicate the process has stopped. If we don't get one, check to
// make sure no one asked us to exit
bool is_running = false;
DataExtractor exc_reply_packet;
do
{
switch (event_type)
{
case eBroadcastBitAsyncContinue:
{
is_running = true;
if (process->m_comm.WaitForPacketWithTimeoutMicroSeconds (exc_reply_packet, 1 * USEC_PER_SEC))
{
ThreadSP thread_sp (process->GetKernelThread());
if (thread_sp)
{
lldb::RegisterContextSP reg_ctx_sp (thread_sp->GetRegisterContext());
if (reg_ctx_sp)
reg_ctx_sp->InvalidateAllRegisters();
static_cast<ThreadKDP *>(thread_sp.get())->SetStopInfoFrom_KDP_EXCEPTION (exc_reply_packet);
}
// TODO: parse the stop reply packet
is_running = false;
process->SetPrivateState(eStateStopped);
}
else
{
// Check to see if we are supposed to exit. There is no way to
// interrupt a running kernel, so all we can do is wait for an
// exception or detach...
if (listener.GetNextEvent(event_sp))
{
// We got an event, go through the loop again
event_type = event_sp->GetType();
}
}
}
break;
case eBroadcastBitAsyncThreadShouldExit:
if (log)
log->Printf ("ProcessKDP::AsyncThread (pid = %" PRIu64 ") got eBroadcastBitAsyncThreadShouldExit...",
pid);
done = true;
is_running = false;
break;
default:
if (log)
log->Printf ("ProcessKDP::AsyncThread (pid = %" PRIu64 ") got unknown event 0x%8.8x",
pid,
event_type);
done = true;
is_running = false;
break;
}
} while (is_running);
}
else
{
if (log)
log->Printf ("ProcessKDP::AsyncThread (pid = %" PRIu64 ") listener.WaitForEvent (NULL, event_sp) => false",
pid);
done = true;
}
}
}
if (log)
log->Printf ("ProcessKDP::AsyncThread (arg = %p, pid = %" PRIu64 ") thread exiting...",
arg,
pid);
process->m_async_thread.Reset();
return NULL;
}
