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