1 files changed, 91 insertions, 0 deletions
diff --git a/netwerk/base/PartiallySeekableInputStream.h b/netwerk/base/PartiallySeekableInputStream.h
new file mode 100644
index 0000000000..92ad4114c5
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+++ b/netwerk/base/PartiallySeekableInputStream.h
@@ -0,0 +1,91 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* 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/. */
+
+#ifndef PartiallySeekableInputStream_h
+#define PartiallySeekableInputStream_h
+
+#include "mozilla/Attributes.h"
+#include "mozilla/Mutex.h"
+#include "nsCOMPtr.h"
+#include "nsIAsyncInputStream.h"
+#include "nsICloneableInputStream.h"
+#include "nsIInputStreamLength.h"
+#include "nsIIPCSerializableInputStream.h"
+#include "nsISeekableStream.h"
+
+namespace mozilla {
+namespace net {
+
+// A wrapper for making a stream seekable for the first |aBufferSize| bytes.
+// Note that this object takes the ownership of the underlying stream.
+
+class PartiallySeekableInputStream final : public nsISeekableStream,
+                                           public nsIAsyncInputStream,
+                                           public nsICloneableInputStream,
+                                           public nsIIPCSerializableInputStream,
+                                           public nsIInputStreamCallback,
+                                           public nsIInputStreamLength,
+                                           public nsIAsyncInputStreamLength,
+                                           public nsIInputStreamLengthCallback {
+ public:
+  NS_DECL_THREADSAFE_ISUPPORTS
+  NS_DECL_NSIINPUTSTREAM
+  NS_DECL_NSISEEKABLESTREAM
+  NS_DECL_NSITELLABLESTREAM
+  NS_DECL_NSIASYNCINPUTSTREAM
+  NS_DECL_NSICLONEABLEINPUTSTREAM
+  NS_DECL_NSIIPCSERIALIZABLEINPUTSTREAM
+  NS_DECL_NSIINPUTSTREAMCALLBACK
+  NS_DECL_NSIINPUTSTREAMLENGTH
+  NS_DECL_NSIASYNCINPUTSTREAMLENGTH
+  NS_DECL_NSIINPUTSTREAMLENGTHCALLBACK
+
+  explicit PartiallySeekableInputStream(
+      already_AddRefed<nsIInputStream> aInputStream,
+      uint64_t aBufferSize = 4096);
+
+ private:
+  PartiallySeekableInputStream(
+      already_AddRefed<nsIInputStream> aClonedBaseStream,
+      PartiallySeekableInputStream* aClonedFrom);
+
+  ~PartiallySeekableInputStream() = default;
+
+  void Init();
+
+  template <typename M>
+  void SerializeInternal(mozilla::ipc::InputStreamParams& aParams,
+                         FileDescriptorArray& aFileDescriptors,
+                         bool aDelayedStart, uint32_t aMaxSize,
+                         uint32_t* aSizeUsed, M* aManager);
+
+  nsCOMPtr<nsIInputStream> mInputStream;
+
+  // Raw pointers because these are just QI of mInputStream.
+  nsICloneableInputStream* mWeakCloneableInputStream;
+  nsIIPCSerializableInputStream* mWeakIPCSerializableInputStream;
+  nsIAsyncInputStream* mWeakAsyncInputStream;
+  nsIInputStreamLength* mWeakInputStreamLength;
+  nsIAsyncInputStreamLength* mWeakAsyncInputStreamLength;
+
+  // Protected by mutex.
+  nsCOMPtr<nsIInputStreamCallback> mAsyncWaitCallback;
+
+  // Protected by mutex.
+  nsCOMPtr<nsIInputStreamLengthCallback> mAsyncInputStreamLengthCallback;
+
+  nsTArray<char> mCachedBuffer;
+
+  uint64_t mBufferSize;
+  uint64_t mPos;
+  bool mClosed;
+
+  Mutex mMutex;
+};
+
+}  // namespace net
+}  // namespace mozilla
+
+#endif  // PartiallySeekableInputStream_h