ladybird/Userland/Libraries/LibCompress/Gzip.h
Tim Schumacher d5871f5717 AK: Rename Stream::{read,write} to Stream::{read_some,write_some}
Similar to POSIX read, the basic read and write functions of AK::Stream
do not have a lower limit of how much data they read or write (apart
from "none at all").

Rename the functions to "read some [data]" and "write some [data]" (with
"data" being omitted, since everything here is reading and writing data)
to make them sufficiently distinct from the functions that ensure to
use the entire buffer (which should be the go-to function for most
usages).

No functional changes, just a lot of new FIXMEs.
2023-03-13 15:16:20 +00:00

99 lines
2.7 KiB
C++

/*
* Copyright (c) 2020-2022, the SerenityOS developers.
* Copyright (c) 2021, Idan Horowitz <idan.horowitz@serenityos.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#pragma once
#include <AK/NonnullOwnPtr.h>
#include <AK/OwnPtr.h>
#include <AK/Stream.h>
#include <LibCompress/Deflate.h>
#include <LibCrypto/Checksum/CRC32.h>
namespace Compress {
constexpr u8 gzip_magic_1 = 0x1f;
constexpr u8 gzip_magic_2 = 0x8b;
struct [[gnu::packed]] BlockHeader {
u8 identification_1;
u8 identification_2;
u8 compression_method;
u8 flags;
LittleEndian<u32> modification_time;
u8 extra_flags;
u8 operating_system;
bool valid_magic_number() const;
bool supported_by_implementation() const;
};
struct Flags {
static constexpr u8 FTEXT = 1 << 0;
static constexpr u8 FHCRC = 1 << 1;
static constexpr u8 FEXTRA = 1 << 2;
static constexpr u8 FNAME = 1 << 3;
static constexpr u8 FCOMMENT = 1 << 4;
static constexpr u8 MAX = FTEXT | FHCRC | FEXTRA | FNAME | FCOMMENT;
};
class GzipDecompressor final : public Stream {
public:
GzipDecompressor(NonnullOwnPtr<Stream>);
~GzipDecompressor();
virtual ErrorOr<Bytes> read_some(Bytes) override;
virtual ErrorOr<size_t> write_some(ReadonlyBytes) override;
virtual bool is_eof() const override;
virtual bool is_open() const override { return true; }
virtual void close() override {};
static ErrorOr<ByteBuffer> decompress_all(ReadonlyBytes);
static Optional<DeprecatedString> describe_header(ReadonlyBytes);
static bool is_likely_compressed(ReadonlyBytes bytes);
private:
class Member {
public:
static ErrorOr<NonnullOwnPtr<Member>> construct(BlockHeader header, Stream&);
BlockHeader m_header;
NonnullOwnPtr<DeflateDecompressor> m_stream;
Crypto::Checksum::CRC32 m_checksum;
size_t m_nread { 0 };
private:
Member(BlockHeader, NonnullOwnPtr<DeflateDecompressor>);
};
Member const& current_member() const { return *m_current_member; }
Member& current_member() { return *m_current_member; }
NonnullOwnPtr<Stream> m_input_stream;
u8 m_partial_header[sizeof(BlockHeader)];
size_t m_partial_header_offset { 0 };
OwnPtr<Member> m_current_member {};
bool m_eof { false };
};
class GzipCompressor final : public Stream {
public:
GzipCompressor(MaybeOwned<Stream>);
virtual ErrorOr<Bytes> read_some(Bytes) override;
virtual ErrorOr<size_t> write_some(ReadonlyBytes) override;
virtual bool is_eof() const override;
virtual bool is_open() const override;
virtual void close() override;
static ErrorOr<ByteBuffer> compress_all(ReadonlyBytes bytes);
private:
MaybeOwned<Stream> m_output_stream;
};
}