system/ulib/blobfs/include/blobfs/compression/compressor.h

// Copyright 2019 The Fuchsia Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#pragma once

#include <fbl/macros.h>
#include <lz4/lz4frame.h>
#include <zircon/types.h>
#include <zstd/zstd.h>

namespace blobfs {

enum class CompressionAlgorithm {
    LZ4,
    ZSTD,
};

// A Compressor is used to compress data transparently before it is written
// back to disk.
class Compressor {
public:
    Compressor() = default;
    virtual ~Compressor() = default;
    DISALLOW_COPY_ASSIGN_AND_MOVE(Compressor);

    // Returns the compressed size of the data so far. Simply starting initialization
    // may result in a nonzero |Size()|.
    virtual size_t Size() const = 0;

    // Continues the compression after initialization.
    virtual zx_status_t Update(const void* input_data, size_t input_length) = 0;

    // Finishes the compression process.
    // Must be called before compression is considered complete.
    virtual zx_status_t End() = 0;
};

} // namespace blobfs