Pipeline will execute a callback whenever an run-time error has happened.

BUG=16738
TEST=pipeline_impl_unittest.cc
Review URL: http://codereview.chromium.org/159373

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@21877 0039d316-1c4b-4281-b951-d872f2087c98

3 files changed, 25 insertions, 1 deletions

diff --git a/media/base/pipeline_impl.cc b/media/base/pipeline_impl.cc
index 9b482f8..20bd4cb 100644
--- a/media/base/pipeline_impl.cc
+++ b/media/base/pipeline_impl.cc
@@ -237,6 +237,10 @@ PipelineError PipelineImpl::GetError() const {
   return error_;
 }
 
+void PipelineImpl::SetPipelineErrorCallback(PipelineCallback* error_callback) {
+  error_callback_.reset(error_callback);
+}
+
 void PipelineImpl::ResetState() {
   AutoLock auto_lock(lock_);
   running_          = false;
@@ -533,6 +537,12 @@ void PipelineImpl::ErrorChangedTask(PipelineError error) {
 
   // Destroy every filter and reset the pipeline as well.
   DestroyFilters();
+
+  // If our owner has requested to be notified of an error, execute
+  // |error_callback_| unless we have a "good" error.
+  if (error_callback_.get() && error != PIPELINE_STOPPING) {
+    error_callback_->Run();
+  }
 }
 
 void PipelineImpl::PlaybackRateChangedTask(float playback_rate) {
diff --git a/media/base/pipeline_impl.h b/media/base/pipeline_impl.h
index 4eed436..be3ad28 100644
--- a/media/base/pipeline_impl.h
+++ b/media/base/pipeline_impl.h
@@ -7,9 +7,10 @@
 #ifndef MEDIA_BASE_PIPELINE_IMPL_H_
 #define MEDIA_BASE_PIPELINE_IMPL_H_
 
+#include <map>
+#include <set>
 #include <string>
 #include <vector>
-#include <set>
 
 #include "base/message_loop.h"
 #include "base/ref_counted.h"
@@ -82,6 +83,11 @@ class PipelineImpl : public Pipeline, public FilterHost {
   virtual void GetVideoSize(size_t* width_out, size_t* height_out) const;
   virtual PipelineError GetError() const;
 
+  // |error_callback_| will be executed upon an error in the pipeline. If
+  // |error_callback_| is NULL, it is ignored. The pipeline takes ownernship
+  // of |error_callback|.
+  virtual void SetPipelineErrorCallback(PipelineCallback* error_callback);
+
  private:
   // Pipeline states, as described above.
   enum State {
@@ -314,6 +320,7 @@ class PipelineImpl : public Pipeline, public FilterHost {
   // Callbacks for various pipeline operations.
   scoped_ptr<PipelineCallback> seek_callback_;
   scoped_ptr<PipelineCallback> stop_callback_;
+  scoped_ptr<PipelineCallback> error_callback_;
 
   // Vector of our filters and map maintaining the relationship between the
   // FilterType and the filter itself.
diff --git a/media/base/pipeline_impl_unittest.cc b/media/base/pipeline_impl_unittest.cc
index e745761..6913cdc 100644
--- a/media/base/pipeline_impl_unittest.cc
+++ b/media/base/pipeline_impl_unittest.cc
@@ -32,6 +32,7 @@ class CallbackHelper {
   MOCK_METHOD0(OnStart, void());
   MOCK_METHOD0(OnSeek, void());
   MOCK_METHOD0(OnStop, void());
+  MOCK_METHOD0(OnError, void());
 
  private:
   DISALLOW_COPY_AND_ASSIGN(CallbackHelper);
@@ -48,6 +49,9 @@ class PipelineImplTest : public ::testing::Test {
   PipelineImplTest()
       : pipeline_(new PipelineImpl(&message_loop_)),
         mocks_(new MockFilterFactory()) {
+    pipeline_->SetPipelineErrorCallback(NewCallback(
+        reinterpret_cast<CallbackHelper*>(&callbacks_),
+        &CallbackHelper::OnError));
   }
 
   virtual ~PipelineImplTest() {
@@ -232,6 +236,7 @@ TEST_F(PipelineImplTest, NeverInitializes) {
 }
 
 TEST_F(PipelineImplTest, RequiredFilterMissing) {
+  EXPECT_CALL(callbacks_, OnError());
   mocks_->set_creation_successful(false);
 
   InitializePipeline();
@@ -245,6 +250,7 @@ TEST_F(PipelineImplTest, URLNotFound) {
       .WillOnce(DoAll(SetError(mocks_->data_source(),
                                PIPELINE_ERROR_URL_NOT_FOUND),
                       Invoke(&RunFilterCallback)));
+  EXPECT_CALL(callbacks_, OnError());
   EXPECT_CALL(*mocks_->data_source(), Stop());
 
   InitializePipeline();
@@ -264,6 +270,7 @@ TEST_F(PipelineImplTest, NoStreams) {
   EXPECT_CALL(*mocks_->demuxer(), GetNumberOfStreams())
       .WillRepeatedly(Return(0));
   EXPECT_CALL(*mocks_->demuxer(), Stop());
+  EXPECT_CALL(callbacks_, OnError());
 
   InitializePipeline();
   EXPECT_FALSE(pipeline_->IsInitialized());