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Libraries: Move to Userland/Libraries/

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This commit is contained in:
Andreas Kling 2021-01-12 12:17:30 +01:00
parent dc28c07fa5
commit 13d7c09125
1857 changed files with 266 additions and 274 deletions
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183
Libraries/LibCompress/Gzip.cpp
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@ -1,183 +0,0 @@
/*
* Copyright (c) 2020, the SerenityOS developers.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <LibCompress/Gzip.h>
#include <AK/MemoryStream.h>
#include <AK/String.h>
namespace Compress {
bool GzipDecompressor::BlockHeader::valid_magic_number() const
{
return identification_1 == 0x1f && identification_2 == 0x8b;
}
bool GzipDecompressor::BlockHeader::supported_by_implementation() const
{
if (compression_method != 0x08) {
// RFC 1952 does not define any compression methods other than deflate.
return false;
}
if (flags > Flags::MAX) {
// RFC 1952 does not define any more flags.
return false;
}
if (flags & Flags::FHCRC) {
TODO();
}
return true;
}
GzipDecompressor::GzipDecompressor(InputStream& stream)
: m_input_stream(stream)
{
}
GzipDecompressor::~GzipDecompressor()
{
m_current_member.clear();
}
// FIXME: Again, there are surely a ton of bugs because the code doesn't check for read errors.
size_t GzipDecompressor::read(Bytes bytes)
{
if (has_any_error() || m_eof)
return 0;
if (m_current_member.has_value()) {
size_t nread = current_member().m_stream.read(bytes);
current_member().m_checksum.update(bytes.trim(nread));
current_member().m_nread += nread;
if (nread < bytes.size()) {
LittleEndian<u32> crc32, input_size;
m_input_stream >> crc32 >> input_size;
if (crc32 != current_member().m_checksum.digest()) {
// FIXME: Somehow the checksum is incorrect?
set_fatal_error();
return 0;
}
if (input_size != current_member().m_nread) {
set_fatal_error();
return 0;
}
m_current_member.clear();
return nread + read(bytes.slice(nread));
}
return nread;
} else {
BlockHeader header;
m_input_stream >> Bytes { &header, sizeof(header) };
if (m_input_stream.handle_any_error()) {
m_eof = true;
return 0;
}
if (!header.valid_magic_number() || !header.supported_by_implementation()) {
set_fatal_error();
return 0;
}
if (header.flags & Flags::FEXTRA) {
LittleEndian<u16> subfield_id, length;
m_input_stream >> subfield_id >> length;
m_input_stream.discard_or_error(length);
}
if (header.flags & Flags::FNAME) {
String original_filename;
m_input_stream >> original_filename;
}
if (header.flags & Flags::FCOMMENT) {
String comment;
m_input_stream >> comment;
}
m_current_member.emplace(header, m_input_stream);
return read(bytes);
}
}
bool GzipDecompressor::read_or_error(Bytes bytes)
{
if (read(bytes) < bytes.size()) {
set_fatal_error();
return false;
}
return true;
}
bool GzipDecompressor::discard_or_error(size_t count)
{
u8 buffer[4096];
size_t ndiscarded = 0;
while (ndiscarded < count) {
if (unreliable_eof()) {
set_fatal_error();
return false;
}
ndiscarded += read({ buffer, min<size_t>(count - ndiscarded, sizeof(buffer)) });
}
return true;
}
Optional<ByteBuffer> GzipDecompressor::decompress_all(ReadonlyBytes bytes)
{
InputMemoryStream memory_stream { bytes };
GzipDecompressor gzip_stream { memory_stream };
DuplexMemoryStream output_stream;
u8 buffer[4096];
while (!gzip_stream.has_any_error() && !gzip_stream.unreliable_eof()) {
const auto nread = gzip_stream.read({ buffer, sizeof(buffer) });
output_stream.write_or_error({ buffer, nread });
}
if (gzip_stream.handle_any_error())
return {};
return output_stream.copy_into_contiguous_buffer();
}
bool GzipDecompressor::unreliable_eof() const { return m_eof; }
}