Project import generated by Copybara.

PiperOrigin-RevId: 237361882
Change-Id: I109a68f44db867b20f8c6a7732b0ce657133e52a
diff --git a/quic/core/quic_packet_writer_wrapper.h b/quic/core/quic_packet_writer_wrapper.h
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+++ b/quic/core/quic_packet_writer_wrapper.h
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+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef QUICHE_QUIC_CORE_QUIC_PACKET_WRITER_WRAPPER_H_
+#define QUICHE_QUIC_CORE_QUIC_PACKET_WRITER_WRAPPER_H_
+
+#include <cstddef>
+#include <memory>
+
+#include "base/macros.h"
+#include "net/third_party/quiche/src/quic/core/quic_packet_writer.h"
+
+namespace quic {
+
+// Wraps a writer object to allow dynamically extending functionality. Use
+// cases: replace writer while dispatcher and connections hold on to the
+// wrapper; mix in monitoring; mix in mocks in unit tests.
+class QuicPacketWriterWrapper : public QuicPacketWriter {
+ public:
+  QuicPacketWriterWrapper();
+  QuicPacketWriterWrapper(const QuicPacketWriterWrapper&) = delete;
+  QuicPacketWriterWrapper& operator=(const QuicPacketWriterWrapper&) = delete;
+  ~QuicPacketWriterWrapper() override;
+
+  // Default implementation of the QuicPacketWriter interface. Passes everything
+  // to |writer_|.
+  WriteResult WritePacket(const char* buffer,
+                          size_t buf_len,
+                          const QuicIpAddress& self_address,
+                          const QuicSocketAddress& peer_address,
+                          PerPacketOptions* options) override;
+  bool IsWriteBlocked() const override;
+  void SetWritable() override;
+  QuicByteCount GetMaxPacketSize(
+      const QuicSocketAddress& peer_address) const override;
+  bool SupportsReleaseTime() const override;
+  bool IsBatchMode() const override;
+  char* GetNextWriteLocation(const QuicIpAddress& self_address,
+                             const QuicSocketAddress& peer_address) override;
+  WriteResult Flush() override;
+
+  // Takes ownership of |writer|.
+  void set_writer(QuicPacketWriter* writer);
+
+  // Does not take ownership of |writer|.
+  void set_non_owning_writer(QuicPacketWriter* writer);
+
+  virtual void set_peer_address(const QuicSocketAddress& peer_address) {}
+
+  QuicPacketWriter* writer() { return writer_; }
+
+ private:
+  void unset_writer();
+
+  QuicPacketWriter* writer_ = nullptr;
+  bool owns_writer_ = false;
+};
+
+}  // namespace quic
+
+#endif  // QUICHE_QUIC_CORE_QUIC_PACKET_WRITER_WRAPPER_H_