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LibCompress: Port ZlibDecompressor to AK::Stream

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This commit is contained in:
Tim Schumacher 2023-06-08 19:35:44 +02:00 • committed by Sam Atkins
parent 90780d9ade
commit 8a853278d0
7 changed files with 96 additions and 68 deletions
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57
Userland/Libraries/LibCompress/Zlib.cpp
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@ -4,6 +4,7 @@
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <AK/BitStream.h>
#include <AK/IntegralMath.h>
#include <AK/MemoryStream.h>
#include <AK/Span.h>
@ -14,59 +15,53 @@
namespace Compress {
constexpr static size_t Adler32Size = sizeof(u32);
Optional<ZlibDecompressor> ZlibDecompressor::try_create(ReadonlyBytes data)
ErrorOr<NonnullOwnPtr<ZlibDecompressor>> ZlibDecompressor::create(MaybeOwned<Stream> stream)
{
if (data.size() < (sizeof(ZlibHeader) + Adler32Size))
return {};
ZlibHeader header { .as_u16 = data.at(0) << 8 | data.at(1) };
auto header = TRY(stream->read_value<ZlibHeader>());
if (header.compression_method != ZlibCompressionMethod::Deflate || header.compression_info > 7)
return {}; // non-deflate compression
return Error::from_string_literal("Non-DEFLATE compression inside Zlib is not supported");
if (header.present_dictionary)
return {}; // we dont support pre-defined dictionaries
return Error::from_string_literal("Zlib compression with a pre-defined dictionary is currently not supported");
if (header.as_u16 % 31 != 0)
return {}; // error correction code doesn't match
return Error::from_string_literal("Zlib error correction code does not match");
ZlibDecompressor zlib { header, data };
zlib.m_data_bytes = data.slice(2, data.size() - sizeof(ZlibHeader) - Adler32Size);
return zlib;
auto bit_stream = make<LittleEndianInputBitStream>(move(stream));
auto deflate_stream = TRY(Compress::DeflateDecompressor::construct(move(bit_stream)));
return adopt_nonnull_own_or_enomem(new (nothrow) ZlibDecompressor(header, move(deflate_stream)));
}
ZlibDecompressor::ZlibDecompressor(ZlibHeader header, ReadonlyBytes data)
ZlibDecompressor::ZlibDecompressor(ZlibHeader header, NonnullOwnPtr<Stream> stream)
: m_header(header)
, m_input_data(data)
, m_stream(move(stream))
{
}
Optional<ByteBuffer> ZlibDecompressor::decompress()
ErrorOr<Bytes> ZlibDecompressor::read_some(Bytes bytes)
{
auto buffer_or_error = DeflateDecompressor::decompress_all(m_data_bytes);
if (buffer_or_error.is_error())
return {};
return buffer_or_error.release_value();
return m_stream->read_some(bytes);
}
Optional<ByteBuffer> ZlibDecompressor::decompress_all(ReadonlyBytes bytes)
ErrorOr<size_t> ZlibDecompressor::write_some(ReadonlyBytes)
{
auto zlib = try_create(bytes);
if (!zlib.has_value())
return {};
return zlib->decompress();
return Error::from_errno(EBADF);
}
u32 ZlibDecompressor::checksum()
bool ZlibDecompressor::is_eof() const
{
if (!m_checksum) {
auto bytes = m_input_data.slice_from_end(Adler32Size);
m_checksum = bytes.at(0) << 24 | bytes.at(1) << 16 | bytes.at(2) << 8 || bytes.at(3);
}
return m_stream->is_eof();
}
return m_checksum;
bool ZlibDecompressor::is_open() const
{
return m_stream->is_open();
}
void ZlibDecompressor::close()
{
}
ErrorOr<NonnullOwnPtr<ZlibCompressor>> ZlibCompressor::construct(MaybeOwned<Stream> stream, ZlibCompressionLevel compression_level)