chromium/services/network/public/cpp/net_adapters.h

// Copyright 2017 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef SERVICES_NETWORK_PUBLIC_CPP_NET_ADAPTERS_H_
#define SERVICES_NETWORK_PUBLIC_CPP_NET_ADAPTERS_H_

#include <stdint.h>

#include "base/component_export.h"
#include "base/containers/span.h"
#include "mojo/public/cpp/system/data_pipe.h"
#include "net/base/io_buffer.h"

namespace network {

// These adapters are used to transfer data between a Mojo pipe and the net
// library.
//
//   Mojo pipe              Data flow    Network library
//   ----------------------------------------------------------
//   MojoToNetPendingBuffer    --->      MojoToNetIOBuffer
//   NetToMojoPendingBuffer    <---      NetToMojoIOBuffer
//
// While the operation is in progress, the Mojo-side objects keep ownership
// of the Mojo pipe, which in turn is kept alive by the IOBuffer. This allows
// the request to potentially outlive the object managing the translation.
// Mojo side of a Net -> Mojo copy. The buffer is allocated by Mojo.
class COMPONENT_EXPORT(NETWORK_CPP) NetToMojoPendingBuffer
    : public base::RefCountedThreadSafe<NetToMojoPendingBuffer> { … };

// Net side of a Net -> Mojo copy. The data will be read from the network and
// copied into the buffer associated with the pending mojo write.
class COMPONENT_EXPORT(NETWORK_CPP) NetToMojoIOBuffer
    : public net::WrappedIOBuffer { … };

class COMPONENT_EXPORT(NETWORK_CPP) MojoToNetPendingBuffer
    : public base::RefCountedThreadSafe<MojoToNetPendingBuffer> { … };

// Net side of a Mojo -> Net copy. The data will already be in the
// MojoToNetPendingBuffer's buffer.
class COMPONENT_EXPORT(NETWORK_CPP) MojoToNetIOBuffer
    : public net::WrappedIOBuffer { … };

}  // namespace network

#endif  // SERVICES_NETWORK_PUBLIC_CPP_NET_ADAPTERS_H_