tdlight/tdutils/td/utils/Gzip.h

107 lines
2.1 KiB
C++

//
// Copyright Aliaksei Levin (levlam@telegram.org), Arseny Smirnov (arseny30@gmail.com) 2014-2021
//
// Distributed under the Boost Software License, Version 1.0. (See accompanying
// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
//
#pragma once
#include "td/utils/common.h"
#if TD_HAVE_ZLIB
#include "td/utils/buffer.h"
#include "td/utils/Slice.h"
#include "td/utils/Status.h"
namespace td {
class Gzip {
public:
Gzip();
Gzip(const Gzip &) = delete;
Gzip &operator=(const Gzip &) = delete;
Gzip(Gzip &&other) noexcept;
Gzip &operator=(Gzip &&other) noexcept;
~Gzip();
enum class Mode { Empty, Encode, Decode };
Status init(Mode mode) TD_WARN_UNUSED_RESULT {
if (mode == Mode::Encode) {
return init_encode();
} else if (mode == Mode::Decode) {
return init_decode();
}
clear();
return Status::OK();
}
Status init_encode() TD_WARN_UNUSED_RESULT;
Status init_decode() TD_WARN_UNUSED_RESULT;
void set_input(Slice input);
void set_output(MutableSlice output);
void close_input() {
close_input_flag_ = true;
}
bool need_input() const {
return left_input() == 0;
}
bool need_output() const {
return left_output() == 0;
}
size_t left_input() const;
size_t left_output() const;
size_t used_input() const {
return input_size_ - left_input();
}
size_t used_output() const {
return output_size_ - left_output();
}
size_t flush_input() {
auto res = used_input();
input_size_ = left_input();
return res;
}
size_t flush_output() {
auto res = used_output();
output_size_ = left_output();
return res;
}
enum class State { Running, Done };
Result<State> run() TD_WARN_UNUSED_RESULT;
private:
class Impl;
unique_ptr<Impl> impl_;
size_t input_size_ = 0;
size_t output_size_ = 0;
bool close_input_flag_ = false;
Mode mode_ = Mode::Empty;
void init_common();
void clear();
void swap(Gzip &other);
};
BufferSlice gzdecode(Slice s);
BufferSlice gzencode(Slice s, double max_compression_ratio);
} // namespace td
#endif