Make sure that DoResume doesn't stall if we shut down the async thread while DoResume is waiting

for packet confirmation.  
Also added a bit more logging.
Also, unlock the writer end of the run lock in Process.cpp on our way out of the private state
thread so that the Process can shut down cleanly.

<rdar://problem/11228538>

llvm-svn: 154601

2 files changed, 24 insertions, 1 deletions

diff --git a/lldb/source/Plugins/Process/gdb-remote/ProcessGDBRemote.cpp b/lldb/source/Plugins/Process/gdb-remote/ProcessGDBRemote.cpp
index 9b875012a6a..4dba00bb43f 100644
--- a/lldb/source/Plugins/Process/gdb-remote/ProcessGDBRemote.cpp
+++ b/lldb/source/Plugins/Process/gdb-remote/ProcessGDBRemote.cpp
@@ -175,6 +175,7 @@ ProcessGDBRemote::ProcessGDBRemote(Target& target, Listener &listener) :
 {
     m_async_broadcaster.SetEventName (eBroadcastBitAsyncThreadShouldExit,   "async thread should exit");
     m_async_broadcaster.SetEventName (eBroadcastBitAsyncContinue,           "async thread continue");
+    m_async_broadcaster.SetEventName (eBroadcastBitAsyncThreadDidExit,      "async thread did exit");
 }
 
 //----------------------------------------------------------------------
@@ -927,6 +928,8 @@ ProcessGDBRemote::DoResume ()
     Listener listener ("gdb-remote.resume-packet-sent");
     if (listener.StartListeningForEvents (&m_gdb_comm, GDBRemoteCommunication::eBroadcastBitRunPacketSent))
     {
+        listener.StartListeningForEvents (&m_async_broadcaster, ProcessGDBRemote::eBroadcastBitAsyncThreadDidExit);
+        
         StreamString continue_packet;
         bool continue_packet_error = false;
         if (m_gdb_comm.HasAnyVContSupport ())
@@ -1122,10 +1125,29 @@ ProcessGDBRemote::DoResume ()
             TimeValue timeout;
             timeout = TimeValue::Now();
             timeout.OffsetWithSeconds (5);
+            if (!IS_VALID_LLDB_HOST_THREAD(m_async_thread))
+            {
+                error.SetErrorString ("Trying to resume but the async thread is dead.");
+                if (log)
+                    log->Printf ("ProcessGDBRemote::DoResume: Trying to resume but the async thread is dead.");
+                return error;
+            }
+            
             m_async_broadcaster.BroadcastEvent (eBroadcastBitAsyncContinue, new EventDataBytes (continue_packet.GetData(), continue_packet.GetSize()));
 
             if (listener.WaitForEvent (&timeout, event_sp) == false)
+            {
                 error.SetErrorString("Resume timed out.");
+                if (log)
+                    log->Printf ("ProcessGDBRemote::DoResume: Resume timed out.");
+            }
+            else if (event_sp->BroadcasterIs (&m_async_broadcaster))
+            {
+                error.SetErrorString ("Broadcast continue, but the async thread was killed before we got an ack back.");
+                if (log)
+                    log->Printf ("ProcessGDBRemote::DoResume: Broadcast continue, but the async thread was killed before we got an ack back.");
+                return error;
+            }
         }
     }
 
diff --git a/lldb/source/Plugins/Process/gdb-remote/ProcessGDBRemote.h b/lldb/source/Plugins/Process/gdb-remote/ProcessGDBRemote.h
index 6a0758bf199..f0cd5aab18b 100644
--- a/lldb/source/Plugins/Process/gdb-remote/ProcessGDBRemote.h
+++ b/lldb/source/Plugins/Process/gdb-remote/ProcessGDBRemote.h
@@ -293,7 +293,8 @@ protected:
     enum
     {
         eBroadcastBitAsyncContinue                  = (1 << 0),
-        eBroadcastBitAsyncThreadShouldExit          = (1 << 1)
+        eBroadcastBitAsyncThreadShouldExit          = (1 << 1),
+        eBroadcastBitAsyncThreadDidExit             = (1 << 2)
     };
 
     lldb_private::Flags m_flags;            // Process specific flags (see eFlags enums)