NaCl VS Addin Crash Fix

visual_studio/NativeClientVSAddIn/NativeClientVSAddIn/PluginDebuggerBase.cs

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 namespace NativeClientVSAddIn
 {
   using System;
   using System.Collections.Generic;
   using System.Windows.Forms;
 
@@ skipping 105 matching lines @@
     }
 
     /// <summary>
     /// This is called periodically by the Visual Studio UI thread to look for our plug-in process
     /// and attach the debugger to it.  The call is triggered by the pluginFinderTimer_ object.
     /// </summary>
     /// <param name="unused">The parameter is not used.</param>
     /// <param name="unused1">The parameter is not used.</param>
     public void FindAndAttachToPlugin(object unused, EventArgs unused1)
     {
+      StringComparison ignoreCase = StringComparison.InvariantCultureIgnoreCase;
+
       // This function is called by the main Visual Studio event loop and we may have put the event
       // on the queue just before disposing it meaning this could be called after we've disposed.
       if (Disposed)
       {
         return;
       }
 
-      StringComparison ignoreCase = StringComparison.InvariantCultureIgnoreCase;
-
       // Set the main chrome process that was started by visual studio.  If it's not chrome
       // or not found then we have no business attaching to any plug-ins so return.
       if (debuggedChromeMainProcess_ == null)
       {
         foreach (Process proc in Dte.Debugger.DebuggedProcesses)
         {
           if (proc.Name.EndsWith(Strings.ChromeProcessName, ignoreCase))
           {
             debuggedChromeMainProcess_ = System.Diagnostics.Process.GetProcessById(proc.ProcessID);
             break;
           }
         }
 
         return;
       }
 
+      if (debuggedChromeMainProcess_.HasExited)
+      {
+        // Might happen if we're shutting down debugging.
+        return;
+      }
+
       // Get the list of all descendants of the main chrome process.
       uint mainChromeProcId = (uint)debuggedChromeMainProcess_.Id;
       List<ProcessInfo> chromeDescendants = processSearcher_.GetDescendants(mainChromeProcId);
-      string mainChromeFlags = chromeDescendants.Find(p => p.ID == mainChromeProcId).CommandLine;
+      if (chromeDescendants.Count == 0)
+      {
+        // Might happen if we're shutting down debugging.
+        return;
+      }
+
+      ProcessInfo mainProcInfo = chromeDescendants.Find(p => p.ID == mainChromeProcId);
+      if (mainProcInfo == null)
+      {
+        // Might happen if we're shutting down debugging.
+        return;
+      }
+
+      string mainChromeFlags = mainProcInfo.CommandLine;
 
       // From the list of descendants, find the plug-in by it's command line arguments and
       // process name as well as not being attached to already.
       List<ProcessInfo> plugins = chromeDescendants.FindAll(p =>
           IsPluginProcess(p, mainChromeFlags) && !pluginFinderForbiddenPids_.Contains(p.ID));
 
       // Attach to all plug-ins that we found.
       foreach (ProcessInfo process in plugins)
       {
         // If we are attaching to a plug-in, add it to the forbidden list to ensure we
@@ skipping 46 matching lines @@
         this.ProcessID = pid;
       }
 
       /// <summary>
       /// Gets or sets process ID of the found plug-in.
       /// </summary>
       public uint ProcessID { get; set; }
     }
   }
 }