diff -r 000000000000 -r 6474c204b198 content/media/BufferMediaResource.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/content/media/BufferMediaResource.h	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,173 @@
+/* vim:set ts=2 sw=2 sts=2 et cindent: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#if !defined(BufferMediaResource_h_)
+#define BufferMediaResource_h_
+
+#include "MediaResource.h"
+#include "nsISeekableStream.h"
+#include "nsIPrincipal.h"
+#include <algorithm>
+
+namespace mozilla {
+
+// A simple MediaResource based on an in memory buffer.  This class accepts
+// the address and the length of the buffer, and simulates a read/seek API
+// on top of it.  The Read implementation involves copying memory, which is
+// unfortunate, but the MediaResource interface mandates that.
+class BufferMediaResource : public MediaResource
+{
+public:
+  BufferMediaResource(const uint8_t* aBuffer,
+                      uint32_t aLength,
+                      nsIPrincipal* aPrincipal,
+                      const nsACString& aContentType) :
+    mBuffer(aBuffer),
+    mLength(aLength),
+    mOffset(0),
+    mPrincipal(aPrincipal),
+    mContentType(aContentType)
+  {
+    MOZ_COUNT_CTOR(BufferMediaResource);
+  }
+
+  virtual ~BufferMediaResource()
+  {
+    MOZ_COUNT_DTOR(BufferMediaResource);
+  }
+
+  virtual nsresult Close() { return NS_OK; }
+  virtual void Suspend(bool aCloseImmediately) {}
+  virtual void Resume() {}
+  // Get the current principal for the channel
+  virtual already_AddRefed<nsIPrincipal> GetCurrentPrincipal()
+  {
+    nsCOMPtr<nsIPrincipal> principal = mPrincipal;
+    return principal.forget();
+  }
+  virtual bool CanClone() { return false; }
+  virtual already_AddRefed<MediaResource> CloneData(MediaDecoder* aDecoder)
+  {
+    return nullptr;
+  }
+
+  // These methods are called off the main thread.
+  // The mode is initially MODE_PLAYBACK.
+  virtual void SetReadMode(MediaCacheStream::ReadMode aMode) {}
+  virtual void SetPlaybackRate(uint32_t aBytesPerSecond) {}
+  virtual nsresult Read(char* aBuffer, uint32_t aCount, uint32_t* aBytes)
+  {
+    *aBytes = std::min(mLength - mOffset, aCount);
+    memcpy(aBuffer, mBuffer + mOffset, *aBytes);
+    mOffset += *aBytes;
+    MOZ_ASSERT(mOffset <= mLength);
+    return NS_OK;
+  }
+  virtual nsresult ReadAt(int64_t aOffset, char* aBuffer,
+                          uint32_t aCount, uint32_t* aBytes)
+  {
+    nsresult rv = Seek(nsISeekableStream::NS_SEEK_SET, aOffset);
+    if (NS_FAILED(rv)) return rv;
+    return Read(aBuffer, aCount, aBytes);
+  }
+  virtual nsresult Seek(int32_t aWhence, int64_t aOffset)
+  {
+    MOZ_ASSERT(aOffset <= UINT32_MAX);
+    switch (aWhence) {
+    case nsISeekableStream::NS_SEEK_SET:
+      if (aOffset < 0 || aOffset > mLength) {
+        return NS_ERROR_FAILURE;
+      }
+      mOffset = static_cast<uint32_t> (aOffset);
+      break;
+    case nsISeekableStream::NS_SEEK_CUR:
+      if (aOffset >= mLength - mOffset) {
+        return NS_ERROR_FAILURE;
+      }
+      mOffset += static_cast<uint32_t> (aOffset);
+      break;
+    case nsISeekableStream::NS_SEEK_END:
+      if (aOffset < 0 || aOffset > mLength) {
+        return NS_ERROR_FAILURE;
+      }
+      mOffset = mLength - aOffset;
+      break;
+    }
+
+    return NS_OK;
+  }
+  virtual void StartSeekingForMetadata() {}
+  virtual void EndSeekingForMetadata() {}
+  virtual int64_t Tell() { return mOffset; }
+
+  virtual void Pin() {}
+  virtual void Unpin() {}
+  virtual double GetDownloadRate(bool* aIsReliable) { return 0.; }
+  virtual int64_t GetLength() { return mLength; }
+  virtual int64_t GetNextCachedData(int64_t aOffset) { return aOffset; }
+  virtual int64_t GetCachedDataEnd(int64_t aOffset) { return mLength; }
+  virtual bool IsDataCachedToEndOfResource(int64_t aOffset) { return true; }
+  virtual bool IsSuspendedByCache() { return false; }
+  virtual bool IsSuspended() { return false; }
+  virtual nsresult ReadFromCache(char* aBuffer,
+                                 int64_t aOffset,
+                                 uint32_t aCount)
+  {
+    if (aOffset < 0) {
+      return NS_ERROR_FAILURE;
+    }
+
+    uint32_t bytes = std::min(mLength - static_cast<uint32_t>(aOffset), aCount);
+    memcpy(aBuffer, mBuffer + aOffset, bytes);
+    return NS_OK;
+  }
+
+  virtual nsresult Open(nsIStreamListener** aStreamListener)
+  {
+    return NS_ERROR_FAILURE;
+  }
+
+  virtual nsresult GetCachedRanges(nsTArray<MediaByteRange>& aRanges)
+  {
+    aRanges.AppendElement(MediaByteRange(0, mLength));
+    return NS_OK;
+  }
+
+  bool IsTransportSeekable() MOZ_OVERRIDE { return true; }
+
+  virtual const nsCString& GetContentType() const MOZ_OVERRIDE
+  {
+    return mContentType;
+  }
+
+  virtual size_t SizeOfExcludingThis(
+                        MallocSizeOf aMallocSizeOf) const MOZ_OVERRIDE
+  {
+    // Not owned:
+    // - mBuffer
+    // - mPrincipal
+    size_t size = MediaResource::SizeOfExcludingThis(aMallocSizeOf);
+    size += mContentType.SizeOfExcludingThisIfUnshared(aMallocSizeOf);
+
+    return size;
+  }
+
+  virtual size_t SizeOfIncludingThis(
+                        MallocSizeOf aMallocSizeOf) const MOZ_OVERRIDE
+  {
+    return aMallocSizeOf(this) + SizeOfExcludingThis(aMallocSizeOf);
+  }
+
+private:
+  const uint8_t * mBuffer;
+  uint32_t mLength;
+  uint32_t mOffset;
+  nsCOMPtr<nsIPrincipal> mPrincipal;
+  const nsAutoCString mContentType;
+};
+
+}
+
+#endif