Guard against the plugin being deleted unexpectedly.

BUG=none
TEST=manually stress tested plugin creation and destruction

Review URL: http://codereview.chromium.org/2848004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@49869 0039d316-1c4b-4281-b951-d872f2087c98

4 files changed, 27 insertions, 2 deletions

diff --git a/o3d/core/cross/client.cc b/o3d/core/cross/client.cc
index a6f9c32..271df8e42 100644
--- a/o3d/core/cross/client.cc
+++ b/o3d/core/cross/client.cc
@@ -252,6 +252,16 @@ void Client::RenderClientInner(bool present, bool send_callback) {
     profiler_->ProfileStart("Render callback");
     if (send_callback)
       render_callback_manager_.Run(render_event_);
+
+    // Calling back to JavaScript may have caused the plugin to be
+    // torn down. Guard carefully against this.
+    if (!profiler_.IsAvailable()) {
+      if (renderer_.IsAvailable()) {
+        renderer_->FinishRendering();
+      }
+      return;
+    }
+
     profiler_->ProfileStop("Render callback");
 
     if (!render_tree_called_) {
diff --git a/o3d/plugin/cross/main.cc b/o3d/plugin/cross/main.cc
index fe49c7c..e552bce 100644
--- a/o3d/plugin/cross/main.cc
+++ b/o3d/plugin/cross/main.cc
@@ -109,8 +109,11 @@ void NPP_URLNotify(NPP instance, const char *url, NPReason reason,
                    void *notifyData) {
   HANDLE_CRASHES;
   PluginObject *obj = static_cast<PluginObject*>(instance->pdata);
-  StreamManager *stream_manager = obj->stream_manager();
-  stream_manager->URLNotify(url, reason, notifyData);
+  // Make sure the plugin hasn't been destroyed already.
+  if (obj) {
+    StreamManager *stream_manager = obj->stream_manager();
+    stream_manager->URLNotify(url, reason, notifyData);
+  }
 }
 
 NPError NPP_GetValue(NPP instance, NPPVariable variable, void *value) {
diff --git a/o3d/plugin/mac/main_mac.mm b/o3d/plugin/mac/main_mac.mm
index 6f3a15d..2daefe5 100644
--- a/o3d/plugin/mac/main_mac.mm
+++ b/o3d/plugin/mac/main_mac.mm
@@ -983,6 +983,14 @@ NPError NPP_Destroy(NPP instance, NPSavedData** save) {
 
     // TODO(maf) / TODO(kbr): are we leaking AGL / CGL contexts?
 
+    if (obj->drawing_model_ == NPDrawingModelCoreAnimation) {
+      O3DLayer* layer = ObjO3DLayer(obj);
+      if (layer) {
+        // Prevent the layer from rendering any more.
+        [layer setPluginObject:NULL];
+      }
+    }
+
     obj->TearDown();
     NPN_ReleaseObject(obj);
     instance->pdata = NULL;
diff --git a/o3d/plugin/mac/o3d_layer.mm b/o3d/plugin/mac/o3d_layer.mm
index a566f1b6..ee85df9 100644
--- a/o3d/plugin/mac/o3d_layer.mm
+++ b/o3d/plugin/mac/o3d_layer.mm
@@ -71,6 +71,10 @@ using o3d::DisplayWindowMac;
              pixelFormat:(CGLPixelFormatObj)pf
             forLayerTime:(CFTimeInterval)t
              displayTime:(const CVTimeStamp *)ts {
+  // Watch out for the plugin being destroyed out from under us.
+  if (!obj_) {
+    return;
+  }
 
   // Set the current context to the one given to us.
   CGLSetCurrentContext(ctx);