src/dawn/wire/ChunkedCommandHandler.h

// Copyright 2020 The Dawn & Tint Authors
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#ifndef SRC_DAWN_WIRE_CHUNKEDCOMMANDHANDLER_H_
#define SRC_DAWN_WIRE_CHUNKEDCOMMANDHANDLER_H_

#include <cstdint>
#include <limits>
#include <memory>

#include "absl/container/flat_hash_map.h"
#include "dawn/common/Assert.h"
#include "dawn/wire/Wire.h"
#include "dawn/wire/WireCmd_autogen.h"
#include "dawn/wire/WireDeserializeAllocator.h"

namespace dawn::wire {

class ChunkedCommandHandler : public CommandHandler {
  public:
    ChunkedCommandHandler();
    ~ChunkedCommandHandler() override;

  protected:
    WireResult HandleChunkedCommand(DeserializeBuffer* deserializeBuffer);

    WireDeserializeAllocator mAllocator;

  private:
    // This map keeps track of all in-flight chunked commands. Note that because |HandleCommands|
    // must be called in a thread-safe manner, we do not need to explicitly synchronize access to
    // this map.
    struct ChunkedCommand {
        size_t remainingSize = 0;
        size_t putOffset = 0;
        std::unique_ptr<char[]> data = nullptr;
    };
    absl::flat_hash_map<uint64_t, ChunkedCommand> mChunkedCommands;
};

}  // namespace dawn::wire

#endif  // SRC_DAWN_WIRE_CHUNKEDCOMMANDHANDLER_H_