import FIREFOX_52_6_0esr_RELEASE from mozilla-esr52 hg repo

dom/media/BufferMediaResource.h

@@ -0,0 +1,141 @@
+/* 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);
+  }
+
+protected:
+  virtual ~BufferMediaResource()
+  {
+    MOZ_COUNT_DTOR(BufferMediaResource);
+  }
+
+private:
+  nsresult Close() override { return NS_OK; }
+  void Suspend(bool aCloseImmediately) override {}
+  void Resume() override {}
+  // Get the current principal for the channel
+  already_AddRefed<nsIPrincipal> GetCurrentPrincipal() override
+  {
+    nsCOMPtr<nsIPrincipal> principal = mPrincipal;
+    return principal.forget();
+  }
+  bool CanClone() override { return false; }
+  already_AddRefed<MediaResource> CloneData(MediaResourceCallback*) override
+  {
+    return nullptr;
+  }
+
+  // These methods are called off the main thread.
+  // The mode is initially MODE_PLAYBACK.
+  void SetReadMode(MediaCacheStream::ReadMode aMode) override {}
+  void SetPlaybackRate(uint32_t aBytesPerSecond) override {}
+  nsresult ReadAt(int64_t aOffset, char* aBuffer,
+                  uint32_t aCount, uint32_t* aBytes) override
+  {
+    if (aOffset < 0 || aOffset > mLength) {
+      return NS_ERROR_FAILURE;
+    }
+    *aBytes = std::min(mLength - static_cast<uint32_t>(aOffset), aCount);
+    memcpy(aBuffer, mBuffer + aOffset, *aBytes);
+    mOffset = aOffset + *aBytes;
+    return NS_OK;
+  }
+  int64_t Tell() override { return mOffset; }
+
+  void Pin() override {}
+  void Unpin() override {}
+  double GetDownloadRate(bool* aIsReliable) override { *aIsReliable = false; return 0.; }
+  int64_t GetLength() override { return mLength; }
+  int64_t GetNextCachedData(int64_t aOffset) override { return aOffset; }
+  int64_t GetCachedDataEnd(int64_t aOffset) override { return mLength; }
+  bool IsDataCachedToEndOfResource(int64_t aOffset) override { return true; }
+  bool IsSuspendedByCache() override { return false; }
+  bool IsSuspended() override { return false; }
+  nsresult ReadFromCache(char* aBuffer,
+                         int64_t aOffset,
+                         uint32_t aCount) override
+  {
+    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;
+  }
+
+  nsresult Open(nsIStreamListener** aStreamListener) override
+  {
+    return NS_ERROR_FAILURE;
+  }
+
+  nsresult GetCachedRanges(MediaByteRangeSet& aRanges) override
+  {
+    aRanges += MediaByteRange(0, int64_t(mLength));
+    return NS_OK;
+  }
+
+  bool IsTransportSeekable() override { return true; }
+
+  const nsCString& GetContentType() const override
+  {
+    return mContentType;
+  }
+
+  size_t SizeOfExcludingThis(MallocSizeOf aMallocSizeOf) const override
+  {
+    // Not owned:
+    // - mBuffer
+    // - mPrincipal
+    size_t size = MediaResource::SizeOfExcludingThis(aMallocSizeOf);
+    size += mContentType.SizeOfExcludingThisIfUnshared(aMallocSizeOf);
+
+    return size;
+  }
+
+  size_t SizeOfIncludingThis(MallocSizeOf aMallocSizeOf) const override
+  {
+    return aMallocSizeOf(this) + SizeOfExcludingThis(aMallocSizeOf);
+  }
+
+private:
+  const uint8_t * mBuffer;
+  uint32_t mLength;
+  uint32_t mOffset;
+  nsCOMPtr<nsIPrincipal> mPrincipal;
+  const nsCString mContentType;
+};
+
+} // namespace mozilla
+
+#endif