[Lldb-commits] [lldb] r154368 - /lldb/trunk/source/Target/Process.cpp

[Jim Ingham]

Author: jingham
Date: Mon Apr  9 20:21:57 2012
New Revision: 154368

URL: http://llvm.org/viewvc/llvm-project?rev=154368&view=rev
Log:
Two changes, 

1) Start the PrivateStateThread stopped, and then in
StartPrivateStateThread, make the private state thread and then
resume it before we say the thread is created.  That way we know it is
listening for events by the time we get out of
StartPrivateStateThread.

2) Backstop running a thread plan when calling Process::RunThreadPlan
on the private state thread with a ThreadPlanBase so that running the
plan doesn't pass its stop events to whatever plans happen to be above
us on the thread plan stack.

Modified:
    lldb/trunk/source/Target/Process.cpp

Modified: lldb/trunk/source/Target/Process.cpp
URL: http://llvm.org/viewvc/llvm-project/lldb/trunk/source/Target/Process.cpp?rev=154368&r1=154367&r2=154368&view=diff
==============================================================================
--- lldb/trunk/source/Target/Process.cpp (original)
+++ lldb/trunk/source/Target/Process.cpp Mon Apr  9 20:21:57 2012
@@ -36,6 +36,7 @@
 #include "lldb/Target/TargetList.h"
 #include "lldb/Target/Thread.h"
 #include "lldb/Target/ThreadPlan.h"
+#include "lldb/Target/ThreadPlanBase.h"
 
 using namespace lldb;
 using namespace lldb_private;
@@ -3102,8 +3103,17 @@
         snprintf(thread_name, sizeof(thread_name), "<lldb.process.internal-state-override(pid=%llu)>", GetID());
     else
         snprintf(thread_name, sizeof(thread_name), "<lldb.process.internal-state(pid=%llu)>", GetID());
+        
+    // Create the private state thread, and start it running.
     m_private_state_thread = Host::ThreadCreate (thread_name, Process::PrivateStateThread, this, NULL);
-    return IS_VALID_LLDB_HOST_THREAD(m_private_state_thread);
+    bool success = IS_VALID_LLDB_HOST_THREAD(m_private_state_thread);
+    if (success)
+    {
+        ResumePrivateStateThread();
+        return true;
+    }
+    else
+        return false;
 }
 
 void
@@ -3247,8 +3257,8 @@
 void *
 Process::RunPrivateStateThread ()
 {
-    bool control_only = false;
-    m_private_state_control_wait.SetValue (false, eBroadcastNever);
+    bool control_only = true;
+    m_private_state_control_wait.SetValue (true, eBroadcastNever);
 
     LogSP log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_PROCESS));
     if (log)
@@ -3910,15 +3920,35 @@
     }
 
     lldb::thread_t backup_private_state_thread = LLDB_INVALID_HOST_THREAD;
+    lldb::StateType old_state;
+    lldb::ThreadPlanSP stopper_base_plan_sp;
     
+    lldb::LogSP log(lldb_private::GetLogIfAnyCategoriesSet (LIBLLDB_LOG_STEP | LIBLLDB_LOG_PROCESS));
     if (Host::GetCurrentThread() == m_private_state_thread)
     {
-        // Yikes, we are running on the private state thread!  So we can't call DoRunThreadPlan on this thread, since
-        // then nobody will be around to fetch internal events.
+        // Yikes, we are running on the private state thread!  So we can't wait for public events on this thread, since
+        // we are the thread that is generating public events.
         // The simplest thing to do is to spin up a temporary thread to handle private state thread events while
-        // we are doing the RunThreadPlan here.
+        // we are fielding public events here.
+        if (log)
+			log->Printf ("Running thread plan on private state thread, spinning up another state thread to handle the events.");
+            
+
         backup_private_state_thread = m_private_state_thread;
-        printf ("Running thread plan on private state thread, spinning up another state thread to handle the events.\n");
+
+        // One other bit of business: we want to run just this thread plan and anything it pushes, and then stop,
+        // returning control here.
+        // But in the normal course of things, the plan above us on the stack would be given a shot at the stop
+        // event before deciding to stop, and we don't want that.  So we insert a "stopper" base plan on the stack
+        // before the plan we want to run.  Since base plans always stop and return control to the user, that will
+        // do just what we want.
+        stopper_base_plan_sp.reset(new ThreadPlanBase (*thread));
+        thread->QueueThreadPlan (stopper_base_plan_sp, false);
+        // Have to make sure our public state is stopped, since otherwise the reporting logic below doesn't work correctly.
+        old_state = m_public_state.GetValue();
+        m_public_state.SetValueNoLock(eStateStopped);
+        
+        // Now spin up the private state thread:
         StartPrivateStateThread(true);
     }
     
@@ -3931,7 +3961,6 @@
     
     ProcessEventHijacker run_thread_plan_hijacker (*this, &listener);
         
-    lldb::LogSP log(lldb_private::GetLogIfAnyCategoriesSet (LIBLLDB_LOG_STEP | LIBLLDB_LOG_PROCESS));
     if (log)
     {
         StreamString s;
@@ -3975,7 +4004,7 @@
             timeout_ptr = &real_timeout;
             
             got_event = listener.WaitForEvent(timeout_ptr, event_sp);
-            if (!got_event) 
+            if (!got_event)
             {
                 if (log)
                     log->PutCString("Didn't get any event after initial resume, exiting.");
@@ -4284,8 +4313,13 @@
     {
         StopPrivateStateThread();
         Error error;
-        // Host::ThreadJoin(m_private_state_thread, &thread_result, &error);
         m_private_state_thread = backup_private_state_thread;
+        if (stopper_base_plan_sp != NULL)
+        {
+            thread->DiscardThreadPlansUpToPlan(stopper_base_plan_sp);
+        }
+        m_public_state.SetValueNoLock(old_state);
+
     }