ppapi: MediaStreamBufferManager: add methods to query queued buffers

BUG=461222

Review URL: https://codereview.chromium.org/1418873003

Cr-Commit-Position: refs/heads/master@{#355825}

3 files changed, 9 insertions, 0 deletions

diff --git a/ppapi/shared_impl/media_stream_buffer_manager.cc b/ppapi/shared_impl/media_stream_buffer_manager.cc
index 29bc153..a9e0e4f 100644
--- a/ppapi/shared_impl/media_stream_buffer_manager.cc
+++ b/ppapi/shared_impl/media_stream_buffer_manager.cc
@@ -72,6 +72,10 @@ void MediaStreamBufferManager::EnqueueBuffer(int32_t index) {
   delegate_->OnNewBufferEnqueued();
 }
 
+bool MediaStreamBufferManager::HasAvailableBuffer() {
+  return !buffer_queue_.empty();
+}
+
 MediaStreamBuffer* MediaStreamBufferManager::GetBufferPointer(int32_t index) {
   if (index < 0 || index >= number_of_buffers_)
     return NULL;
diff --git a/ppapi/shared_impl/media_stream_buffer_manager.h b/ppapi/shared_impl/media_stream_buffer_manager.h
index 28d8e80..7633624 100644
--- a/ppapi/shared_impl/media_stream_buffer_manager.h
+++ b/ppapi/shared_impl/media_stream_buffer_manager.h
@@ -70,6 +70,9 @@ class PPAPI_SHARED_EXPORT MediaStreamBufferManager {
   // Puts a buffer into |buffer_queue_|.
   void EnqueueBuffer(int32_t index);
 
+  // Queries whether a buffer will be returned by DequeueBuffer().
+  bool HasAvailableBuffer();
+
   // Gets the buffer address for the given buffer index.
   MediaStreamBuffer* GetBufferPointer(int32_t index);
 
diff --git a/ppapi/shared_impl/media_stream_buffer_manager_unittest.cc b/ppapi/shared_impl/media_stream_buffer_manager_unittest.cc
index 3db0117..75c5660 100644
--- a/ppapi/shared_impl/media_stream_buffer_manager_unittest.cc
+++ b/ppapi/shared_impl/media_stream_buffer_manager_unittest.cc
@@ -56,6 +56,7 @@ TEST(MediaStreamBufferManager, General) {
 
     EXPECT_EQ(kNumberOfBuffers, manager.number_of_buffers());
     EXPECT_EQ(kBufferSize, manager.buffer_size());
+    EXPECT_TRUE(manager.HasAvailableBuffer());
 
     // Test DequeueBuffer() and GetBufferPointer()
     for (int32_t i = 0; i < kNumberOfBuffers; ++i) {
@@ -78,6 +79,7 @@ TEST(MediaStreamBufferManager, General) {
     EXPECT_EQ(2, manager.DequeueBuffer());
     EXPECT_EQ(PP_ERROR_FAILED, manager.DequeueBuffer());
     EXPECT_EQ(PP_ERROR_FAILED, manager.DequeueBuffer());
+    EXPECT_FALSE(manager.HasAvailableBuffer());
 
     // Returns NULL for invalid index to GetBufferPointer()
     EXPECT_EQ(NULL, manager.GetBufferPointer(-1));