From d17ceb8a8f9965f199a547f007298c1d6192504f Mon Sep 17 00:00:00 2001
From: Karl Tomlinson <karlt+@karlt.net>
Date: Wed, 16 Aug 2017 18:37:30 +1200
Subject: [PATCH] bug 1391482 permit AudioChunk channel data initialization
 when mBuffer is not shared r=padenot

MozReview-Commit-ID: AZ30fTVHHce

--HG--
extra : rebase_source : 313f0e643c9fce3500fe4c238929c4636560834e
---
 dom/media/AudioSegment.h | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/dom/media/AudioSegment.h b/dom/media/AudioSegment.h
index 00b805db1021..c78f56872bf3 100644
--- a/dom/media/AudioSegment.h
+++ b/dom/media/AudioSegment.h
@@ -233,6 +233,18 @@ struct AudioChunk {
       (&mChannelData);
   }
 
+  /**
+   * ChannelFloatsForWrite() should be used only when mBuffer is owned solely
+   * by the calling thread.
+   */
+  template<typename T>
+  T* ChannelDataForWrite(size_t aChannel)
+  {
+    MOZ_ASSERT(AudioSampleTypeToFormat<T>::Format == mBufferFormat);
+    MOZ_ASSERT(!mBuffer->IsShared());
+    return static_cast<T*>(const_cast<void*>(mChannelData[aChannel]));
+  }
+
   PrincipalHandle GetPrincipalHandle() const { return mPrincipalHandle; }
 
   StreamTime mDuration; // in frames within the buffer