mirror of
https://github.com/LadybirdBrowser/ladybird.git
synced 2024-08-17 09:20:28 +03:00
LibCore+LibHTTP+LibGfx: Switch to LibCompress
This commit removes the only 3rd party library (and its usages) in serenity: puff, which is used for deflate decompression. and replaces it with the existing original serenity implementation in LibCompress. :^)
This commit is contained in:
parent
373a595c56
commit
c12781a6a2
Notes:
sideshowbarker
2024-07-18 21:44:21 +09:00
Author: https://github.com/IdanHo Commit: https://github.com/SerenityOS/serenity/commit/c12781a6a2d Pull-request: https://github.com/SerenityOS/serenity/pull/5625
@ -22,8 +22,6 @@ files = subprocess.run(
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":!:Base",
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":!:Kernel/FileSystem/ext2_fs.h",
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":!:Userland/Libraries/LibC/getopt.cpp",
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":!:Userland/Libraries/LibCore/puff.h",
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":!:Userland/Libraries/LibCore/puff.cpp",
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":!:Userland/Libraries/LibELF/exec_elf.h"
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],
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capture_output=True
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@ -42,8 +42,6 @@ done < <(git ls-files -- \
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':!:Base' \
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':!:Kernel/FileSystem/ext2_fs.h' \
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':!:Userland/Libraries/LibC/getopt.cpp' \
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':!:Userland/Libraries/LibCore/puff.h' \
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':!:Userland/Libraries/LibCore/puff.cpp' \
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':!:Userland/Libraries/LibELF/exec_elf.h' \
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)
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@ -14,8 +14,6 @@ if [ "$#" -eq "1" ]; then
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':!:Kernel/FileSystem/ext2_fs.h' \
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':!:Userland/Libraries/LibC/getopt.cpp' \
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':!:Userland/Libraries/LibC/syslog.h' \
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':!:Userland/Libraries/LibCore/puff.h' \
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':!:Userland/Libraries/LibCore/puff.cpp' \
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':!:Userland/Libraries/LibELF/exec_elf.h'
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)
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else
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@ -31,9 +31,14 @@
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namespace Compress {
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bool GzipDecompressor::is_likely_compressed(ReadonlyBytes bytes)
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{
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return bytes.size() >= 2 && bytes[0] == gzip_magic_1 && bytes[1] == gzip_magic_2;
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}
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bool GzipDecompressor::BlockHeader::valid_magic_number() const
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{
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return identification_1 == 0x1f && identification_2 == 0x8b;
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return identification_1 == gzip_magic_1 && identification_2 == gzip_magic_2;
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}
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bool GzipDecompressor::BlockHeader::supported_by_implementation() const
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@ -48,10 +53,6 @@ bool GzipDecompressor::BlockHeader::supported_by_implementation() const
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return false;
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}
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if (flags & Flags::FHCRC) {
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TODO();
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}
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return true;
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}
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@ -128,6 +129,12 @@ size_t GzipDecompressor::read(Bytes bytes)
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m_input_stream >> comment;
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}
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if (header.flags & Flags::FHCRC) {
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LittleEndian<u16> crc16;
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m_input_stream >> crc16;
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// FIXME: we should probably verify this instead of just assuming it matches
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}
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m_current_member.emplace(header, m_input_stream);
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return read(bytes);
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}
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@ -31,6 +31,9 @@
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namespace Compress {
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constexpr u8 gzip_magic_1 = 0x1f;
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constexpr u8 gzip_magic_2 = 0x8b;
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class GzipDecompressor final : public InputStream {
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public:
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GzipDecompressor(InputStream&);
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@ -43,6 +46,7 @@ public:
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bool unreliable_eof() const override;
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static Optional<ByteBuffer> decompress_all(ReadonlyBytes);
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static bool is_likely_compressed(ReadonlyBytes bytes);
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private:
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struct [[gnu::packed]] BlockHeader {
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@ -12,7 +12,6 @@ set(SOURCES
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FileWatcher.cpp
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File.cpp
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GetPassword.cpp
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Gzip.cpp
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IODevice.cpp
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LocalServer.cpp
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LocalSocket.cpp
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@ -23,7 +22,6 @@ set(SOURCES
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Object.cpp
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ProcessStatisticsReader.cpp
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Property.cpp
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puff.cpp
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SocketAddress.cpp
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Socket.cpp
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StandardPaths.cpp
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@ -1,160 +0,0 @@
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/*
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* Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
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* All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions are met:
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*
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* 1. Redistributions of source code must retain the above copyright notice, this
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* list of conditions and the following disclaimer.
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*
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* 2. Redistributions in binary form must reproduce the above copyright notice,
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* this list of conditions and the following disclaimer in the documentation
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* and/or other materials provided with the distribution.
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*
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* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
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* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
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* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
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* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
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* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
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* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
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* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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*/
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#include <AK/ByteBuffer.h>
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#include <AK/Debug.h>
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#include <AK/Optional.h>
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#include <LibCore/Gzip.h>
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#include <LibCore/puff.h>
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#include <limits.h>
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#include <stddef.h>
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namespace Core {
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bool Gzip::is_compressed(const ByteBuffer& data)
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{
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return data.size() > 2 && data[0] == 0x1F && data[1] == 0x8b;
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}
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// skips the gzip header
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// see: https://tools.ietf.org/html/rfc1952#page-5
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static Optional<ByteBuffer> get_gzip_payload(const ByteBuffer& data)
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{
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size_t current = 0;
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auto read_byte = [&]() {
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if (current >= data.size()) {
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VERIFY_NOT_REACHED();
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return (u8)0;
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}
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return data[current++];
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};
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#if GZIP_DEBUG
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dbgln("get_gzip_payload: Skipping over gzip header.");
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#endif
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// Magic Header
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if (read_byte() != 0x1F || read_byte() != 0x8B) {
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dbgln("get_gzip_payload: Wrong magic number.");
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return Optional<ByteBuffer>();
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}
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// Compression method
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auto method = read_byte();
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if (method != 8) {
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dbgln("get_gzip_payload: Wrong compression method={}", method);
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return Optional<ByteBuffer>();
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}
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u8 flags = read_byte();
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// Timestamp, Extra flags, OS
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current += 6;
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// FEXTRA
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if (flags & 4) {
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u16 length = read_byte() & read_byte() << 8;
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dbgln("get_gzip_payload: Header has FEXTRA flag set. length={}", length);
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current += length;
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}
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// FNAME
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if (flags & 8) {
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dbgln("get_gzip_payload: Header has FNAME flag set.");
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while (read_byte() != '\0')
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;
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}
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// FCOMMENT
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if (flags & 16) {
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dbgln("get_gzip_payload: Header has FCOMMENT flag set.");
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while (read_byte() != '\0')
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;
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}
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// FHCRC
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if (flags & 2) {
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dbgln("get_gzip_payload: Header has FHCRC flag set.");
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current += 2;
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}
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auto new_size = data.size() - current;
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dbgln_if(GZIP_DEBUG, "get_gzip_payload: Returning slice from {} with size {}", current, new_size);
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return data.slice(current, new_size);
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}
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Optional<ByteBuffer> Gzip::decompress(const ByteBuffer& data)
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{
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VERIFY(is_compressed(data));
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dbgln_if(GZIP_DEBUG, "Gzip::decompress: Decompressing gzip compressed data. size={}", data.size());
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auto optional_payload = get_gzip_payload(data);
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if (!optional_payload.has_value()) {
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return Optional<ByteBuffer>();
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}
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auto source = optional_payload.value();
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unsigned long source_len = source.size();
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auto destination = ByteBuffer::create_uninitialized(1024);
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while (true) {
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unsigned long destination_len = destination.size();
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if constexpr (GZIP_DEBUG) {
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dbgln("Gzip::decompress: Calling puff()");
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dbgln(" destination_data = {}", destination.data());
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dbgln(" destination_len = {}", destination_len);
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dbgln(" source_data = {}", source.data());
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dbgln(" source_len = {}", source_len);
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}
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auto puff_ret = puff(
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destination.data(), &destination_len,
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source.data(), &source_len);
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if (puff_ret == 0) {
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#if GZIP_DEBUG
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dbgln("Gzip::decompress: Decompression success.");
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#endif
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destination.trim(destination_len);
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break;
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}
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if (puff_ret == 1) {
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// FIXME: Find a better way of decompressing without needing to try over and over again.
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#if GZIP_DEBUG
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dbgln("Gzip::decompress: Output buffer exhausted. Growing.");
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#endif
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destination.grow(destination.size() * 2);
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} else {
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dbgln("Gzip::decompress: Error. puff() returned: {}", puff_ret);
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VERIFY_NOT_REACHED();
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}
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}
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return destination;
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}
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}
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@ -1,41 +0,0 @@
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/*
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* Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
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* All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions are met:
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*
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* 1. Redistributions of source code must retain the above copyright notice, this
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* list of conditions and the following disclaimer.
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*
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* 2. Redistributions in binary form must reproduce the above copyright notice,
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* this list of conditions and the following disclaimer in the documentation
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* and/or other materials provided with the distribution.
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*
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* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
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* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
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* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
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* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
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* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
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* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
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* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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*/
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#pragma once
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#include <AK/ByteBuffer.h>
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#include <AK/Optional.h>
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#include <AK/String.h>
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namespace Core {
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class Gzip {
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public:
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static bool is_compressed(const ByteBuffer& data);
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static Optional<ByteBuffer> decompress(const ByteBuffer& data);
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};
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}
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@ -1,832 +0,0 @@
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/*
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* puff.c
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* Copyright (C) 2002-2013 Mark Adler
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* For conditions of distribution and use, see copyright notice in puff.h
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* version 2.3, 21 Jan 2013
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*
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* puff.c is a simple inflate written to be an unambiguous way to specify the
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* deflate format. It is not written for speed but rather simplicity. As a
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* side benefit, this code might actually be useful when small code is more
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* important than speed, such as bootstrap applications. For typical deflate
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* data, zlib's inflate() is about four times as fast as puff(). zlib's
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* inflate compiles to around 20K on my machine, whereas puff.c compiles to
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* around 4K on my machine (a PowerPC using GNU cc). If the faster decode()
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* function here is used, then puff() is only twice as slow as zlib's
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* inflate().
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*
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* All dynamically allocated memory comes from the stack. The stack required
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* is less than 2K bytes. This code is compatible with 16-bit int's and
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* assumes that long's are at least 32 bits. puff.c uses the short data type,
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* assumed to be 16 bits, for arrays in order to conserve memory. The code
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* works whether integers are stored big endian or little endian.
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*
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* In the comments below are "Format notes" that describe the inflate process
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* and document some of the less obvious aspects of the format. This source
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* code is meant to supplement RFC 1951, which formally describes the deflate
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* format:
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*
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* http://www.zlib.org/rfc-deflate.html
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*/
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/*
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* Change history:
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*
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* 1.0 10 Feb 2002 - First version
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* 1.1 17 Feb 2002 - Clarifications of some comments and notes
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* - Update puff() dest and source pointers on negative
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* errors to facilitate debugging deflators
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* - Remove longest from struct huffman -- not needed
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* - Simplify offs[] index in construct()
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* - Add input size and checking, using longjmp() to
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* maintain easy readability
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* - Use short data type for large arrays
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* - Use pointers instead of long to specify source and
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* destination sizes to avoid arbitrary 4 GB limits
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* 1.2 17 Mar 2002 - Add faster version of decode(), doubles speed (!),
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* but leave simple version for readabilty
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* - Make sure invalid distances detected if pointers
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* are 16 bits
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* - Fix fixed codes table error
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* - Provide a scanning mode for determining size of
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* uncompressed data
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* 1.3 20 Mar 2002 - Go back to lengths for puff() parameters [Gailly]
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* - Add a puff.h file for the interface
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* - Add braces in puff() for else do [Gailly]
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* - Use indexes instead of pointers for readability
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* 1.4 31 Mar 2002 - Simplify construct() code set check
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* - Fix some comments
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* - Add FIXLCODES #define
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* 1.5 6 Apr 2002 - Minor comment fixes
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* 1.6 7 Aug 2002 - Minor format changes
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* 1.7 3 Mar 2003 - Added test code for distribution
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* - Added zlib-like license
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* 1.8 9 Jan 2004 - Added some comments on no distance codes case
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* 1.9 21 Feb 2008 - Fix bug on 16-bit integer architectures [Pohland]
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* - Catch missing end-of-block symbol error
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* 2.0 25 Jul 2008 - Add #define to permit distance too far back
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* - Add option in TEST code for puff to write the data
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* - Add option in TEST code to skip input bytes
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* - Allow TEST code to read from piped stdin
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* 2.1 4 Apr 2010 - Avoid variable initialization for happier compilers
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* - Avoid unsigned comparisons for even happier compilers
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* 2.2 25 Apr 2010 - Fix bug in variable initializations [Oberhumer]
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* - Add const where appropriate [Oberhumer]
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* - Split if's and ?'s for coverage testing
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* - Break out test code to separate file
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* - Move NIL to puff.h
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* - Allow incomplete code only if single code length is 1
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* - Add full code coverage test to Makefile
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* 2.3 21 Jan 2013 - Check for invalid code length codes in dynamic blocks
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*/
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#include "puff.h" /* prototype for puff() */
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#include <setjmp.h> /* for setjmp(), longjmp(), and jmp_buf */
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#define local static /* for local function definitions */
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/*
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* Maximums for allocations and loops. It is not useful to change these --
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* they are fixed by the deflate format.
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*/
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#define MAXBITS 15 /* maximum bits in a code */
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#define MAXLCODES 286 /* maximum number of literal/length codes */
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#define MAXDCODES 30 /* maximum number of distance codes */
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#define MAXCODES (MAXLCODES + MAXDCODES) /* maximum codes lengths to read */
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#define FIXLCODES 288 /* number of fixed literal/length codes */
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/* input and output state */
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struct state {
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/* output state */
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unsigned char* out; /* output buffer */
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unsigned long outlen; /* available space at out */
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unsigned long outcnt; /* bytes written to out so far */
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/* input state */
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const unsigned char* in; /* input buffer */
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unsigned long inlen; /* available input at in */
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unsigned long incnt; /* bytes read so far */
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int bitbuf; /* bit buffer */
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int bitcnt; /* number of bits in bit buffer */
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/* input limit error return state for bits() and decode() */
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jmp_buf env;
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};
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/*
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* Return need bits from the input stream. This always leaves less than
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* eight bits in the buffer. bits() works properly for need == 0.
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*
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* Format notes:
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*
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* - Bits are stored in bytes from the least significant bit to the most
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* significant bit. Therefore bits are dropped from the bottom of the bit
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* buffer, using shift right, and new bytes are appended to the top of the
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* bit buffer, using shift left.
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*/
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local int bits(struct state* s, int need)
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{
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long val; /* bit accumulator (can use up to 20 bits) */
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/* load at least need bits into val */
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val = s->bitbuf;
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while (s->bitcnt < need) {
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if (s->incnt == s->inlen)
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longjmp(s->env, 1); /* out of input */
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val |= (long)(s->in[s->incnt++]) << s->bitcnt; /* load eight bits */
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s->bitcnt += 8;
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}
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/* drop need bits and update buffer, always zero to seven bits left */
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s->bitbuf = (int)(val >> need);
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s->bitcnt -= need;
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/* return need bits, zeroing the bits above that */
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return (int)(val & ((1L << need) - 1));
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}
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/*
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* Process a stored block.
|
||||
*
|
||||
* Format notes:
|
||||
*
|
||||
* - After the two-bit stored block type (00), the stored block length and
|
||||
* stored bytes are byte-aligned for fast copying. Therefore any leftover
|
||||
* bits in the byte that has the last bit of the type, as many as seven, are
|
||||
* discarded. The value of the discarded bits are not defined and should not
|
||||
* be checked against any expectation.
|
||||
*
|
||||
* - The second inverted copy of the stored block length does not have to be
|
||||
* checked, but it's probably a good idea to do so anyway.
|
||||
*
|
||||
* - A stored block can have zero length. This is sometimes used to byte-align
|
||||
* subsets of the compressed data for random access or partial recovery.
|
||||
*/
|
||||
local int stored(struct state* s)
|
||||
{
|
||||
unsigned len; /* length of stored block */
|
||||
|
||||
/* discard leftover bits from current byte (assumes s->bitcnt < 8) */
|
||||
s->bitbuf = 0;
|
||||
s->bitcnt = 0;
|
||||
|
||||
/* get length and check against its one's complement */
|
||||
if (s->incnt + 4 > s->inlen)
|
||||
return 2; /* not enough input */
|
||||
len = s->in[s->incnt++];
|
||||
len |= s->in[s->incnt++] << 8;
|
||||
if (s->in[s->incnt++] != (~len & 0xff) || s->in[s->incnt++] != ((~len >> 8) & 0xff))
|
||||
return -2; /* didn't match complement! */
|
||||
|
||||
/* copy len bytes from in to out */
|
||||
if (s->incnt + len > s->inlen)
|
||||
return 2; /* not enough input */
|
||||
if (s->out != NIL) {
|
||||
if (s->outcnt + len > s->outlen)
|
||||
return 1; /* not enough output space */
|
||||
while (len--)
|
||||
s->out[s->outcnt++] = s->in[s->incnt++];
|
||||
} else { /* just scanning */
|
||||
s->outcnt += len;
|
||||
s->incnt += len;
|
||||
}
|
||||
|
||||
/* done with a valid stored block */
|
||||
return 0;
|
||||
}
|
||||
|
||||
/*
|
||||
* Huffman code decoding tables. count[1..MAXBITS] is the number of symbols of
|
||||
* each length, which for a canonical code are stepped through in order.
|
||||
* symbol[] are the symbol values in canonical order, where the number of
|
||||
* entries is the sum of the counts in count[]. The decoding process can be
|
||||
* seen in the function decode() below.
|
||||
*/
|
||||
struct huffman {
|
||||
short* count; /* number of symbols of each length */
|
||||
short* symbol; /* canonically ordered symbols */
|
||||
};
|
||||
|
||||
/*
|
||||
* Decode a code from the stream s using huffman table h. Return the symbol or
|
||||
* a negative value if there is an error. If all of the lengths are zero, i.e.
|
||||
* an empty code, or if the code is incomplete and an invalid code is received,
|
||||
* then -10 is returned after reading MAXBITS bits.
|
||||
*
|
||||
* Format notes:
|
||||
*
|
||||
* - The codes as stored in the compressed data are bit-reversed relative to
|
||||
* a simple integer ordering of codes of the same lengths. Hence below the
|
||||
* bits are pulled from the compressed data one at a time and used to
|
||||
* build the code value reversed from what is in the stream in order to
|
||||
* permit simple integer comparisons for decoding. A table-based decoding
|
||||
* scheme (as used in zlib) does not need to do this reversal.
|
||||
*
|
||||
* - The first code for the shortest length is all zeros. Subsequent codes of
|
||||
* the same length are simply integer increments of the previous code. When
|
||||
* moving up a length, a zero bit is appended to the code. For a complete
|
||||
* code, the last code of the longest length will be all ones.
|
||||
*
|
||||
* - Incomplete codes are handled by this decoder, since they are permitted
|
||||
* in the deflate format. See the format notes for fixed() and dynamic().
|
||||
*/
|
||||
#ifdef SLOW
|
||||
local int decode(struct state* s, const struct huffman* h)
|
||||
{
|
||||
int len; /* current number of bits in code */
|
||||
int code; /* len bits being decoded */
|
||||
int first; /* first code of length len */
|
||||
int count; /* number of codes of length len */
|
||||
int index; /* index of first code of length len in symbol table */
|
||||
|
||||
code = first = index = 0;
|
||||
for (len = 1; len <= MAXBITS; len++) {
|
||||
code |= bits(s, 1); /* get next bit */
|
||||
count = h->count[len];
|
||||
if (code - count < first) /* if length len, return symbol */
|
||||
return h->symbol[index + (code - first)];
|
||||
index += count; /* else update for next length */
|
||||
first += count;
|
||||
first <<= 1;
|
||||
code <<= 1;
|
||||
}
|
||||
return -10; /* ran out of codes */
|
||||
}
|
||||
|
||||
/*
|
||||
* A faster version of decode() for real applications of this code. It's not
|
||||
* as readable, but it makes puff() twice as fast. And it only makes the code
|
||||
* a few percent larger.
|
||||
*/
|
||||
#else /* !SLOW */
|
||||
local int decode(struct state* s, const struct huffman* h)
|
||||
{
|
||||
int len; /* current number of bits in code */
|
||||
int code; /* len bits being decoded */
|
||||
int first; /* first code of length len */
|
||||
int count; /* number of codes of length len */
|
||||
int index; /* index of first code of length len in symbol table */
|
||||
int bitbuf; /* bits from stream */
|
||||
int left; /* bits left in next or left to process */
|
||||
short* next; /* next number of codes */
|
||||
|
||||
bitbuf = s->bitbuf;
|
||||
left = s->bitcnt;
|
||||
code = first = index = 0;
|
||||
len = 1;
|
||||
next = h->count + 1;
|
||||
while (1) {
|
||||
while (left--) {
|
||||
code |= bitbuf & 1;
|
||||
bitbuf >>= 1;
|
||||
count = *next++;
|
||||
if (code - count < first) { /* if length len, return symbol */
|
||||
s->bitbuf = bitbuf;
|
||||
s->bitcnt = (s->bitcnt - len) & 7;
|
||||
return h->symbol[index + (code - first)];
|
||||
}
|
||||
index += count; /* else update for next length */
|
||||
first += count;
|
||||
first <<= 1;
|
||||
code <<= 1;
|
||||
len++;
|
||||
}
|
||||
left = (MAXBITS + 1) - len;
|
||||
if (left == 0)
|
||||
break;
|
||||
if (s->incnt == s->inlen)
|
||||
longjmp(s->env, 1); /* out of input */
|
||||
bitbuf = s->in[s->incnt++];
|
||||
if (left > 8)
|
||||
left = 8;
|
||||
}
|
||||
return -10; /* ran out of codes */
|
||||
}
|
||||
#endif /* SLOW */
|
||||
|
||||
/*
|
||||
* Given the list of code lengths length[0..n-1] representing a canonical
|
||||
* Huffman code for n symbols, construct the tables required to decode those
|
||||
* codes. Those tables are the number of codes of each length, and the symbols
|
||||
* sorted by length, retaining their original order within each length. The
|
||||
* return value is zero for a complete code set, negative for an over-
|
||||
* subscribed code set, and positive for an incomplete code set. The tables
|
||||
* can be used if the return value is zero or positive, but they cannot be used
|
||||
* if the return value is negative. If the return value is zero, it is not
|
||||
* possible for decode() using that table to return an error--any stream of
|
||||
* enough bits will resolve to a symbol. If the return value is positive, then
|
||||
* it is possible for decode() using that table to return an error for received
|
||||
* codes past the end of the incomplete lengths.
|
||||
*
|
||||
* Not used by decode(), but used for error checking, h->count[0] is the number
|
||||
* of the n symbols not in the code. So n - h->count[0] is the number of
|
||||
* codes. This is useful for checking for incomplete codes that have more than
|
||||
* one symbol, which is an error in a dynamic block.
|
||||
*
|
||||
* Assumption: for all i in 0..n-1, 0 <= length[i] <= MAXBITS
|
||||
* This is assured by the construction of the length arrays in dynamic() and
|
||||
* fixed() and is not verified by construct().
|
||||
*
|
||||
* Format notes:
|
||||
*
|
||||
* - Permitted and expected examples of incomplete codes are one of the fixed
|
||||
* codes and any code with a single symbol which in deflate is coded as one
|
||||
* bit instead of zero bits. See the format notes for fixed() and dynamic().
|
||||
*
|
||||
* - Within a given code length, the symbols are kept in ascending order for
|
||||
* the code bits definition.
|
||||
*/
|
||||
local int construct(struct huffman* h, const short* length, int n)
|
||||
{
|
||||
int symbol; /* current symbol when stepping through length[] */
|
||||
int len; /* current length when stepping through h->count[] */
|
||||
int left; /* number of possible codes left of current length */
|
||||
short offs[MAXBITS + 1]; /* offsets in symbol table for each length */
|
||||
|
||||
/* count number of codes of each length */
|
||||
for (len = 0; len <= MAXBITS; len++)
|
||||
h->count[len] = 0;
|
||||
for (symbol = 0; symbol < n; symbol++)
|
||||
(h->count[length[symbol]])++; /* assumes lengths are within bounds */
|
||||
if (h->count[0] == n) /* no codes! */
|
||||
return 0; /* complete, but decode() will fail */
|
||||
|
||||
/* check for an over-subscribed or incomplete set of lengths */
|
||||
left = 1; /* one possible code of zero length */
|
||||
for (len = 1; len <= MAXBITS; len++) {
|
||||
left <<= 1; /* one more bit, double codes left */
|
||||
left -= h->count[len]; /* deduct count from possible codes */
|
||||
if (left < 0)
|
||||
return left; /* over-subscribed--return negative */
|
||||
} /* left > 0 means incomplete */
|
||||
|
||||
/* generate offsets into symbol table for each length for sorting */
|
||||
offs[1] = 0;
|
||||
for (len = 1; len < MAXBITS; len++)
|
||||
offs[len + 1] = offs[len] + h->count[len];
|
||||
|
||||
/*
|
||||
* put symbols in table sorted by length, by symbol order within each
|
||||
* length
|
||||
*/
|
||||
for (symbol = 0; symbol < n; symbol++)
|
||||
if (length[symbol] != 0)
|
||||
h->symbol[offs[length[symbol]]++] = symbol;
|
||||
|
||||
/* return zero for complete set, positive for incomplete set */
|
||||
return left;
|
||||
}
|
||||
|
||||
/*
|
||||
* Decode literal/length and distance codes until an end-of-block code.
|
||||
*
|
||||
* Format notes:
|
||||
*
|
||||
* - Compressed data that is after the block type if fixed or after the code
|
||||
* description if dynamic is a combination of literals and length/distance
|
||||
* pairs terminated by and end-of-block code. Literals are simply Huffman
|
||||
* coded bytes. A length/distance pair is a coded length followed by a
|
||||
* coded distance to represent a string that occurs earlier in the
|
||||
* uncompressed data that occurs again at the current location.
|
||||
*
|
||||
* - Literals, lengths, and the end-of-block code are combined into a single
|
||||
* code of up to 286 symbols. They are 256 literals (0..255), 29 length
|
||||
* symbols (257..285), and the end-of-block symbol (256).
|
||||
*
|
||||
* - There are 256 possible lengths (3..258), and so 29 symbols are not enough
|
||||
* to represent all of those. Lengths 3..10 and 258 are in fact represented
|
||||
* by just a length symbol. Lengths 11..257 are represented as a symbol and
|
||||
* some number of extra bits that are added as an integer to the base length
|
||||
* of the length symbol. The number of extra bits is determined by the base
|
||||
* length symbol. These are in the static arrays below, lens[] for the base
|
||||
* lengths and lext[] for the corresponding number of extra bits.
|
||||
*
|
||||
* - The reason that 258 gets its own symbol is that the longest length is used
|
||||
* often in highly redundant files. Note that 258 can also be coded as the
|
||||
* base value 227 plus the maximum extra value of 31. While a good deflate
|
||||
* should never do this, it is not an error, and should be decoded properly.
|
||||
*
|
||||
* - If a length is decoded, including its extra bits if any, then it is
|
||||
* followed a distance code. There are up to 30 distance symbols. Again
|
||||
* there are many more possible distances (1..32768), so extra bits are added
|
||||
* to a base value represented by the symbol. The distances 1..4 get their
|
||||
* own symbol, but the rest require extra bits. The base distances and
|
||||
* corresponding number of extra bits are below in the static arrays dist[]
|
||||
* and dext[].
|
||||
*
|
||||
* - Literal bytes are simply written to the output. A length/distance pair is
|
||||
* an instruction to copy previously uncompressed bytes to the output. The
|
||||
* copy is from distance bytes back in the output stream, copying for length
|
||||
* bytes.
|
||||
*
|
||||
* - Distances pointing before the beginning of the output data are not
|
||||
* permitted.
|
||||
*
|
||||
* - Overlapped copies, where the length is greater than the distance, are
|
||||
* allowed and common. For example, a distance of one and a length of 258
|
||||
* simply copies the last byte 258 times. A distance of four and a length of
|
||||
* twelve copies the last four bytes three times. A simple forward copy
|
||||
* ignoring whether the length is greater than the distance or not implements
|
||||
* this correctly. You should not use memcpy() since its behavior is not
|
||||
* defined for overlapped arrays. You should not use memmove() or bcopy()
|
||||
* since though their behavior -is- defined for overlapping arrays, it is
|
||||
* defined to do the wrong thing in this case.
|
||||
*/
|
||||
local int codes(struct state* s,
|
||||
const struct huffman* lencode,
|
||||
const struct huffman* distcode)
|
||||
{
|
||||
int symbol; /* decoded symbol */
|
||||
int len; /* length for copy */
|
||||
unsigned dist; /* distance for copy */
|
||||
static const short lens[29] = { /* Size base for length codes 257..285 */
|
||||
3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 15, 17, 19, 23, 27, 31,
|
||||
35, 43, 51, 59, 67, 83, 99, 115, 131, 163, 195, 227, 258
|
||||
};
|
||||
static const short lext[29] = { /* Extra bits for length codes 257..285 */
|
||||
0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 2, 2,
|
||||
3, 3, 3, 3, 4, 4, 4, 4, 5, 5, 5, 5, 0
|
||||
};
|
||||
static const short dists[30] = { /* Offset base for distance codes 0..29 */
|
||||
1, 2, 3, 4, 5, 7, 9, 13, 17, 25, 33, 49, 65, 97, 129, 193,
|
||||
257, 385, 513, 769, 1025, 1537, 2049, 3073, 4097, 6145,
|
||||
8193, 12289, 16385, 24577
|
||||
};
|
||||
static const short dext[30] = { /* Extra bits for distance codes 0..29 */
|
||||
0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6,
|
||||
7, 7, 8, 8, 9, 9, 10, 10, 11, 11,
|
||||
12, 12, 13, 13
|
||||
};
|
||||
|
||||
/* decode literals and length/distance pairs */
|
||||
do {
|
||||
symbol = decode(s, lencode);
|
||||
if (symbol < 0)
|
||||
return symbol; /* invalid symbol */
|
||||
if (symbol < 256) { /* literal: symbol is the byte */
|
||||
/* write out the literal */
|
||||
if (s->out != NIL) {
|
||||
if (s->outcnt == s->outlen)
|
||||
return 1;
|
||||
s->out[s->outcnt] = symbol;
|
||||
}
|
||||
s->outcnt++;
|
||||
} else if (symbol > 256) { /* length */
|
||||
/* get and compute length */
|
||||
symbol -= 257;
|
||||
if (symbol >= 29)
|
||||
return -10; /* invalid fixed code */
|
||||
len = lens[symbol] + bits(s, lext[symbol]);
|
||||
|
||||
/* get and check distance */
|
||||
symbol = decode(s, distcode);
|
||||
if (symbol < 0)
|
||||
return symbol; /* invalid symbol */
|
||||
dist = dists[symbol] + bits(s, dext[symbol]);
|
||||
#ifndef INFLATE_ALLOW_INVALID_DISTANCE_TOOFAR_ARRR
|
||||
if (dist > s->outcnt)
|
||||
return -11; /* distance too far back */
|
||||
#endif
|
||||
|
||||
/* copy length bytes from distance bytes back */
|
||||
if (s->out != NIL) {
|
||||
if (s->outcnt + len > s->outlen)
|
||||
return 1;
|
||||
while (len--) {
|
||||
s->out[s->outcnt] =
|
||||
#ifdef INFLATE_ALLOW_INVALID_DISTANCE_TOOFAR_ARRR
|
||||
dist > s->outcnt ? 0 :
|
||||
#endif
|
||||
s->out[s->outcnt - dist];
|
||||
s->outcnt++;
|
||||
}
|
||||
} else
|
||||
s->outcnt += len;
|
||||
}
|
||||
} while (symbol != 256); /* end of block symbol */
|
||||
|
||||
/* done with a valid fixed or dynamic block */
|
||||
return 0;
|
||||
}
|
||||
|
||||
/*
|
||||
* Process a fixed codes block.
|
||||
*
|
||||
* Format notes:
|
||||
*
|
||||
* - This block type can be useful for compressing small amounts of data for
|
||||
* which the size of the code descriptions in a dynamic block exceeds the
|
||||
* benefit of custom codes for that block. For fixed codes, no bits are
|
||||
* spent on code descriptions. Instead the code lengths for literal/length
|
||||
* codes and distance codes are fixed. The specific lengths for each symbol
|
||||
* can be seen in the "for" loops below.
|
||||
*
|
||||
* - The literal/length code is complete, but has two symbols that are invalid
|
||||
* and should result in an error if received. This cannot be implemented
|
||||
* simply as an incomplete code since those two symbols are in the "middle"
|
||||
* of the code. They are eight bits long and the longest literal/length\
|
||||
* code is nine bits. Therefore the code must be constructed with those
|
||||
* symbols, and the invalid symbols must be detected after decoding.
|
||||
*
|
||||
* - The fixed distance codes also have two invalid symbols that should result
|
||||
* in an error if received. Since all of the distance codes are the same
|
||||
* length, this can be implemented as an incomplete code. Then the invalid
|
||||
* codes are detected while decoding.
|
||||
*/
|
||||
local int fixed(struct state* s)
|
||||
{
|
||||
static int virgin = 1;
|
||||
static short lencnt[MAXBITS + 1], lensym[FIXLCODES];
|
||||
static short distcnt[MAXBITS + 1], distsym[MAXDCODES];
|
||||
static struct huffman lencode, distcode;
|
||||
|
||||
/* build fixed huffman tables if first call (may not be thread safe) */
|
||||
if (virgin) {
|
||||
int symbol;
|
||||
short lengths[FIXLCODES];
|
||||
|
||||
/* construct lencode and distcode */
|
||||
lencode.count = lencnt;
|
||||
lencode.symbol = lensym;
|
||||
distcode.count = distcnt;
|
||||
distcode.symbol = distsym;
|
||||
|
||||
/* literal/length table */
|
||||
for (symbol = 0; symbol < 144; symbol++)
|
||||
lengths[symbol] = 8;
|
||||
for (; symbol < 256; symbol++)
|
||||
lengths[symbol] = 9;
|
||||
for (; symbol < 280; symbol++)
|
||||
lengths[symbol] = 7;
|
||||
for (; symbol < FIXLCODES; symbol++)
|
||||
lengths[symbol] = 8;
|
||||
construct(&lencode, lengths, FIXLCODES);
|
||||
|
||||
/* distance table */
|
||||
for (symbol = 0; symbol < MAXDCODES; symbol++)
|
||||
lengths[symbol] = 5;
|
||||
construct(&distcode, lengths, MAXDCODES);
|
||||
|
||||
/* do this just once */
|
||||
virgin = 0;
|
||||
}
|
||||
|
||||
/* decode data until end-of-block code */
|
||||
return codes(s, &lencode, &distcode);
|
||||
}
|
||||
|
||||
/*
|
||||
* Process a dynamic codes block.
|
||||
*
|
||||
* Format notes:
|
||||
*
|
||||
* - A dynamic block starts with a description of the literal/length and
|
||||
* distance codes for that block. New dynamic blocks allow the compressor to
|
||||
* rapidly adapt to changing data with new codes optimized for that data.
|
||||
*
|
||||
* - The codes used by the deflate format are "canonical", which means that
|
||||
* the actual bits of the codes are generated in an unambiguous way simply
|
||||
* from the number of bits in each code. Therefore the code descriptions
|
||||
* are simply a list of code lengths for each symbol.
|
||||
*
|
||||
* - The code lengths are stored in order for the symbols, so lengths are
|
||||
* provided for each of the literal/length symbols, and for each of the
|
||||
* distance symbols.
|
||||
*
|
||||
* - If a symbol is not used in the block, this is represented by a zero as
|
||||
* as the code length. This does not mean a zero-length code, but rather
|
||||
* that no code should be created for this symbol. There is no way in the
|
||||
* deflate format to represent a zero-length code.
|
||||
*
|
||||
* - The maximum number of bits in a code is 15, so the possible lengths for
|
||||
* any code are 1..15.
|
||||
*
|
||||
* - The fact that a length of zero is not permitted for a code has an
|
||||
* interesting consequence. Normally if only one symbol is used for a given
|
||||
* code, then in fact that code could be represented with zero bits. However
|
||||
* in deflate, that code has to be at least one bit. So for example, if
|
||||
* only a single distance base symbol appears in a block, then it will be
|
||||
* represented by a single code of length one, in particular one 0 bit. This
|
||||
* is an incomplete code, since if a 1 bit is received, it has no meaning,
|
||||
* and should result in an error. So incomplete distance codes of one symbol
|
||||
* should be permitted, and the receipt of invalid codes should be handled.
|
||||
*
|
||||
* - It is also possible to have a single literal/length code, but that code
|
||||
* must be the end-of-block code, since every dynamic block has one. This
|
||||
* is not the most efficient way to create an empty block (an empty fixed
|
||||
* block is fewer bits), but it is allowed by the format. So incomplete
|
||||
* literal/length codes of one symbol should also be permitted.
|
||||
*
|
||||
* - If there are only literal codes and no lengths, then there are no distance
|
||||
* codes. This is represented by one distance code with zero bits.
|
||||
*
|
||||
* - The list of up to 286 length/literal lengths and up to 30 distance lengths
|
||||
* are themselves compressed using Huffman codes and run-length encoding. In
|
||||
* the list of code lengths, a 0 symbol means no code, a 1..15 symbol means
|
||||
* that length, and the symbols 16, 17, and 18 are run-length instructions.
|
||||
* Each of 16, 17, and 18 are follwed by extra bits to define the length of
|
||||
* the run. 16 copies the last length 3 to 6 times. 17 represents 3 to 10
|
||||
* zero lengths, and 18 represents 11 to 138 zero lengths. Unused symbols
|
||||
* are common, hence the special coding for zero lengths.
|
||||
*
|
||||
* - The symbols for 0..18 are Huffman coded, and so that code must be
|
||||
* described first. This is simply a sequence of up to 19 three-bit values
|
||||
* representing no code (0) or the code length for that symbol (1..7).
|
||||
*
|
||||
* - A dynamic block starts with three fixed-size counts from which is computed
|
||||
* the number of literal/length code lengths, the number of distance code
|
||||
* lengths, and the number of code length code lengths (ok, you come up with
|
||||
* a better name!) in the code descriptions. For the literal/length and
|
||||
* distance codes, lengths after those provided are considered zero, i.e. no
|
||||
* code. The code length code lengths are received in a permuted order (see
|
||||
* the order[] array below) to make a short code length code length list more
|
||||
* likely. As it turns out, very short and very long codes are less likely
|
||||
* to be seen in a dynamic code description, hence what may appear initially
|
||||
* to be a peculiar ordering.
|
||||
*
|
||||
* - Given the number of literal/length code lengths (nlen) and distance code
|
||||
* lengths (ndist), then they are treated as one long list of nlen + ndist
|
||||
* code lengths. Therefore run-length coding can and often does cross the
|
||||
* boundary between the two sets of lengths.
|
||||
*
|
||||
* - So to summarize, the code description at the start of a dynamic block is
|
||||
* three counts for the number of code lengths for the literal/length codes,
|
||||
* the distance codes, and the code length codes. This is followed by the
|
||||
* code length code lengths, three bits each. This is used to construct the
|
||||
* code length code which is used to read the remainder of the lengths. Then
|
||||
* the literal/length code lengths and distance lengths are read as a single
|
||||
* set of lengths using the code length codes. Codes are constructed from
|
||||
* the resulting two sets of lengths, and then finally you can start
|
||||
* decoding actual compressed data in the block.
|
||||
*
|
||||
* - For reference, a "typical" size for the code description in a dynamic
|
||||
* block is around 80 bytes.
|
||||
*/
|
||||
local int dynamic(struct state* s)
|
||||
{
|
||||
int nlen, ndist, ncode; /* number of lengths in descriptor */
|
||||
int index; /* index of lengths[] */
|
||||
int err; /* construct() return value */
|
||||
short lengths[MAXCODES]; /* descriptor code lengths */
|
||||
short lencnt[MAXBITS + 1], lensym[MAXLCODES]; /* lencode memory */
|
||||
short distcnt[MAXBITS + 1], distsym[MAXDCODES]; /* distcode memory */
|
||||
struct huffman lencode, distcode; /* length and distance codes */
|
||||
static const short order[19] = /* permutation of code length codes */
|
||||
{ 16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15 };
|
||||
|
||||
/* construct lencode and distcode */
|
||||
lencode.count = lencnt;
|
||||
lencode.symbol = lensym;
|
||||
distcode.count = distcnt;
|
||||
distcode.symbol = distsym;
|
||||
|
||||
/* get number of lengths in each table, check lengths */
|
||||
nlen = bits(s, 5) + 257;
|
||||
ndist = bits(s, 5) + 1;
|
||||
ncode = bits(s, 4) + 4;
|
||||
if (nlen > MAXLCODES || ndist > MAXDCODES)
|
||||
return -3; /* bad counts */
|
||||
|
||||
/* read code length code lengths (really), missing lengths are zero */
|
||||
for (index = 0; index < ncode; index++)
|
||||
lengths[order[index]] = bits(s, 3);
|
||||
for (; index < 19; index++)
|
||||
lengths[order[index]] = 0;
|
||||
|
||||
/* build huffman table for code lengths codes (use lencode temporarily) */
|
||||
err = construct(&lencode, lengths, 19);
|
||||
if (err != 0) /* require complete code set here */
|
||||
return -4;
|
||||
|
||||
/* read length/literal and distance code length tables */
|
||||
index = 0;
|
||||
while (index < nlen + ndist) {
|
||||
int symbol; /* decoded value */
|
||||
int len; /* last length to repeat */
|
||||
|
||||
symbol = decode(s, &lencode);
|
||||
if (symbol < 0)
|
||||
return symbol; /* invalid symbol */
|
||||
if (symbol < 16) /* length in 0..15 */
|
||||
lengths[index++] = symbol;
|
||||
else { /* repeat instruction */
|
||||
len = 0; /* assume repeating zeros */
|
||||
if (symbol == 16) { /* repeat last length 3..6 times */
|
||||
if (index == 0)
|
||||
return -5; /* no last length! */
|
||||
len = lengths[index - 1]; /* last length */
|
||||
symbol = 3 + bits(s, 2);
|
||||
} else if (symbol == 17) /* repeat zero 3..10 times */
|
||||
symbol = 3 + bits(s, 3);
|
||||
else /* == 18, repeat zero 11..138 times */
|
||||
symbol = 11 + bits(s, 7);
|
||||
if (index + symbol > nlen + ndist)
|
||||
return -6; /* too many lengths! */
|
||||
while (symbol--) /* repeat last or zero symbol times */
|
||||
lengths[index++] = len;
|
||||
}
|
||||
}
|
||||
|
||||
/* check for end-of-block code -- there better be one! */
|
||||
if (lengths[256] == 0)
|
||||
return -9;
|
||||
|
||||
/* build huffman table for literal/length codes */
|
||||
err = construct(&lencode, lengths, nlen);
|
||||
if (err && (err < 0 || nlen != lencode.count[0] + lencode.count[1]))
|
||||
return -7; /* incomplete code ok only for single length 1 code */
|
||||
|
||||
/* build huffman table for distance codes */
|
||||
err = construct(&distcode, lengths + nlen, ndist);
|
||||
if (err && (err < 0 || ndist != distcode.count[0] + distcode.count[1]))
|
||||
return -8; /* incomplete code ok only for single length 1 code */
|
||||
|
||||
/* decode data until end-of-block code */
|
||||
return codes(s, &lencode, &distcode);
|
||||
}
|
||||
|
||||
/*
|
||||
* Inflate source to dest. On return, destlen and sourcelen are updated to the
|
||||
* size of the uncompressed data and the size of the deflate data respectively.
|
||||
* On success, the return value of puff() is zero. If there is an error in the
|
||||
* source data, i.e. it is not in the deflate format, then a negative value is
|
||||
* returned. If there is not enough input available or there is not enough
|
||||
* output space, then a positive error is returned. In that case, destlen and
|
||||
* sourcelen are not updated to facilitate retrying from the beginning with the
|
||||
* provision of more input data or more output space. In the case of invalid
|
||||
* inflate data (a negative error), the dest and source pointers are updated to
|
||||
* facilitate the debugging of deflators.
|
||||
*
|
||||
* puff() also has a mode to determine the size of the uncompressed output with
|
||||
* no output written. For this dest must be (unsigned char *)0. In this case,
|
||||
* the input value of *destlen is ignored, and on return *destlen is set to the
|
||||
* size of the uncompressed output.
|
||||
*
|
||||
* The return codes are:
|
||||
*
|
||||
* 2: available inflate data did not terminate
|
||||
* 1: output space exhausted before completing inflate
|
||||
* 0: successful inflate
|
||||
* -1: invalid block type (type == 3)
|
||||
* -2: stored block length did not match one's complement
|
||||
* -3: dynamic block code description: too many length or distance codes
|
||||
* -4: dynamic block code description: code lengths codes incomplete
|
||||
* -5: dynamic block code description: repeat lengths with no first length
|
||||
* -6: dynamic block code description: repeat more than specified lengths
|
||||
* -7: dynamic block code description: invalid literal/length code lengths
|
||||
* -8: dynamic block code description: invalid distance code lengths
|
||||
* -9: dynamic block code description: missing end-of-block code
|
||||
* -10: invalid literal/length or distance code in fixed or dynamic block
|
||||
* -11: distance is too far back in fixed or dynamic block
|
||||
*
|
||||
* Format notes:
|
||||
*
|
||||
* - Three bits are read for each block to determine the kind of block and
|
||||
* whether or not it is the last block. Then the block is decoded and the
|
||||
* process repeated if it was not the last block.
|
||||
*
|
||||
* - The leftover bits in the last byte of the deflate data after the last
|
||||
* block (if it was a fixed or dynamic block) are undefined and have no
|
||||
* expected values to check.
|
||||
*/
|
||||
int puff(unsigned char* dest, /* pointer to destination pointer */
|
||||
unsigned long* destlen, /* amount of output space */
|
||||
const unsigned char* source, /* pointer to source data pointer */
|
||||
unsigned long* sourcelen) /* amount of input available */
|
||||
{
|
||||
struct state s; /* input/output state */
|
||||
int last, type; /* block information */
|
||||
int err; /* return value */
|
||||
|
||||
/* initialize output state */
|
||||
s.out = dest;
|
||||
s.outlen = *destlen; /* ignored if dest is NIL */
|
||||
s.outcnt = 0;
|
||||
|
||||
/* initialize input state */
|
||||
s.in = source;
|
||||
s.inlen = *sourcelen;
|
||||
s.incnt = 0;
|
||||
s.bitbuf = 0;
|
||||
s.bitcnt = 0;
|
||||
|
||||
/* return if bits() or decode() tries to read past available input */
|
||||
if (setjmp(s.env) != 0) /* if came back here via longjmp() */
|
||||
err = 2; /* then skip do-loop, return error */
|
||||
else {
|
||||
/* process blocks until last block or error */
|
||||
do {
|
||||
last = bits(&s, 1); /* one if last block */
|
||||
type = bits(&s, 2); /* block type 0..3 */
|
||||
err = type == 0 ? stored(&s) : (type == 1 ? fixed(&s) : (type == 2 ? dynamic(&s) : -1)); /* type == 3, invalid */
|
||||
if (err != 0)
|
||||
break; /* return with error */
|
||||
} while (!last);
|
||||
}
|
||||
|
||||
/* update the lengths and return */
|
||||
if (err <= 0) {
|
||||
*destlen = s.outcnt;
|
||||
*sourcelen = s.incnt;
|
||||
}
|
||||
return err;
|
||||
}
|
@ -1,44 +0,0 @@
|
||||
#pragma once
|
||||
|
||||
/* puff.h
|
||||
Copyright (C) 2002-2013 Mark Adler, all rights reserved
|
||||
version 2.3, 21 Jan 2013
|
||||
|
||||
This software is provided 'as-is', without any express or implied
|
||||
warranty. In no event will the author be held liable for any damages
|
||||
arising from the use of this software.
|
||||
|
||||
Permission is granted to anyone to use this software for any purpose,
|
||||
including commercial applications, and to alter it and redistribute it
|
||||
freely, subject to the following restrictions:
|
||||
|
||||
1. The origin of this software must not be misrepresented; you must not
|
||||
claim that you wrote the original software. If you use this software
|
||||
in a product, an acknowledgment in the product documentation would be
|
||||
appreciated but is not required.
|
||||
2. Altered source versions must be plainly marked as such, and must not be
|
||||
misrepresented as being the original software.
|
||||
3. This notice may not be removed or altered from any source distribution.
|
||||
|
||||
Mark Adler madler@alumni.caltech.edu
|
||||
*/
|
||||
|
||||
#ifdef __cplusplus
|
||||
extern "C" {
|
||||
#endif
|
||||
|
||||
/*
|
||||
* See puff.c for purpose and usage.
|
||||
*/
|
||||
#ifndef NIL
|
||||
# define NIL ((unsigned char*)0) /* for no output option */
|
||||
#endif
|
||||
|
||||
int puff(unsigned char* dest, /* pointer to destination pointer */
|
||||
unsigned long* destlen, /* amount of output space */
|
||||
const unsigned char* source, /* pointer to source data pointer */
|
||||
unsigned long* sourcelen); /* amount of input available */
|
||||
|
||||
#ifdef __cplusplus
|
||||
}
|
||||
#endif
|
@ -35,4 +35,4 @@ set(SOURCES
|
||||
)
|
||||
|
||||
serenity_lib(LibGfx gfx)
|
||||
target_link_libraries(LibGfx LibM LibCore LibTTF)
|
||||
target_link_libraries(LibGfx LibM LibCompress LibCore LibTTF)
|
||||
|
@ -28,7 +28,7 @@
|
||||
#include <AK/Endian.h>
|
||||
#include <AK/LexicalPath.h>
|
||||
#include <AK/MappedFile.h>
|
||||
#include <LibCore/puff.h>
|
||||
#include <LibCompress/Gzip.h>
|
||||
#include <LibGfx/PNGLoader.h>
|
||||
#include <fcntl.h>
|
||||
#include <math.h>
|
||||
@ -39,6 +39,7 @@
|
||||
#include <unistd.h>
|
||||
|
||||
#ifdef __serenity__
|
||||
# include <LibCompress/Deflate.h>
|
||||
# include <serenity.h>
|
||||
#endif
|
||||
|
||||
@ -120,8 +121,7 @@ struct PNGLoadingContext {
|
||||
bool has_alpha() const { return color_type & 4 || palette_transparency_data.size() > 0; }
|
||||
Vector<Scanline> scanlines;
|
||||
RefPtr<Gfx::Bitmap> bitmap;
|
||||
u8* decompression_buffer { nullptr };
|
||||
size_t decompression_buffer_size { 0 };
|
||||
ByteBuffer decompression_buffer;
|
||||
Vector<u8> compressed_data;
|
||||
Vector<PaletteEntry> palette_data;
|
||||
Vector<u8> palette_transparency_data;
|
||||
@ -603,7 +603,7 @@ static bool decode_png_chunks(PNGLoadingContext& context)
|
||||
|
||||
static bool decode_png_bitmap_simple(PNGLoadingContext& context)
|
||||
{
|
||||
Streamer streamer(context.decompression_buffer, context.decompression_buffer_size);
|
||||
Streamer streamer(context.decompression_buffer.data(), context.decompression_buffer.size());
|
||||
|
||||
for (int y = 0; y < context.height; ++y) {
|
||||
u8 filter;
|
||||
@ -749,7 +749,7 @@ static bool decode_adam7_pass(PNGLoadingContext& context, Streamer& streamer, in
|
||||
|
||||
static bool decode_png_adam7(PNGLoadingContext& context)
|
||||
{
|
||||
Streamer streamer(context.decompression_buffer, context.decompression_buffer_size);
|
||||
Streamer streamer(context.decompression_buffer.data(), context.decompression_buffer.size());
|
||||
context.bitmap = Bitmap::create_purgeable(context.has_alpha() ? BitmapFormat::RGBA32 : BitmapFormat::RGB32, { context.width, context.height });
|
||||
if (!context.bitmap)
|
||||
return false;
|
||||
@ -777,25 +777,12 @@ static bool decode_png_bitmap(PNGLoadingContext& context)
|
||||
if (context.color_type == 3 && context.palette_data.is_empty())
|
||||
return false; // Didn't see a PLTE chunk for a palettized image, or it was empty.
|
||||
|
||||
unsigned long srclen = context.compressed_data.size() - 6;
|
||||
unsigned long destlen = 0;
|
||||
int ret = puff(nullptr, &destlen, context.compressed_data.data() + 2, &srclen);
|
||||
if (ret != 0) {
|
||||
context.state = PNGLoadingContext::State::Error;
|
||||
return false;
|
||||
}
|
||||
context.decompression_buffer_size = destlen;
|
||||
#ifdef __serenity__
|
||||
context.decompression_buffer = (u8*)mmap_with_name(nullptr, context.decompression_buffer_size, PROT_READ | PROT_WRITE, MAP_ANONYMOUS | MAP_PRIVATE, 0, 0, "PNG decompression buffer");
|
||||
#else
|
||||
context.decompression_buffer = (u8*)mmap(nullptr, context.decompression_buffer_size, PROT_READ | PROT_WRITE, MAP_ANONYMOUS | MAP_PRIVATE, 0, 0);
|
||||
#endif
|
||||
|
||||
ret = puff(context.decompression_buffer, &destlen, context.compressed_data.data() + 2, &srclen);
|
||||
if (ret != 0) {
|
||||
auto result = Compress::DeflateDecompressor::decompress_all(context.compressed_data.span().slice(2));
|
||||
if (!result.has_value()) {
|
||||
context.state = PNGLoadingContext::State::Error;
|
||||
return false;
|
||||
}
|
||||
context.decompression_buffer = result.value();
|
||||
context.compressed_data.clear();
|
||||
|
||||
context.scanlines.ensure_capacity(context.height);
|
||||
@ -812,9 +799,7 @@ static bool decode_png_bitmap(PNGLoadingContext& context)
|
||||
VERIFY_NOT_REACHED();
|
||||
}
|
||||
|
||||
munmap(context.decompression_buffer, context.decompression_buffer_size);
|
||||
context.decompression_buffer = nullptr;
|
||||
context.decompression_buffer_size = 0;
|
||||
context.decompression_buffer.clear();
|
||||
|
||||
context.state = PNGLoadingContext::State::BitmapDecoded;
|
||||
return true;
|
||||
|
@ -7,4 +7,4 @@ set(SOURCES
|
||||
)
|
||||
|
||||
serenity_lib(LibHTTP http)
|
||||
target_link_libraries(LibHTTP LibCore LibTLS)
|
||||
target_link_libraries(LibHTTP LibCompress LibCore LibTLS)
|
||||
|
@ -25,7 +25,6 @@
|
||||
*/
|
||||
|
||||
#include <AK/Debug.h>
|
||||
#include <LibCore/Gzip.h>
|
||||
#include <LibCore/TCPSocket.h>
|
||||
#include <LibHTTP/HttpJob.h>
|
||||
#include <LibHTTP/HttpResponse.h>
|
||||
|
@ -26,7 +26,6 @@
|
||||
|
||||
#include <AK/Debug.h>
|
||||
#include <LibCore/EventLoop.h>
|
||||
#include <LibCore/Gzip.h>
|
||||
#include <LibHTTP/HttpResponse.h>
|
||||
#include <LibHTTP/HttpsJob.h>
|
||||
#include <LibTLS/TLSv12.h>
|
||||
|
@ -25,7 +25,7 @@
|
||||
*/
|
||||
|
||||
#include <AK/Debug.h>
|
||||
#include <LibCore/Gzip.h>
|
||||
#include <LibCompress/Gzip.h>
|
||||
#include <LibCore/TCPSocket.h>
|
||||
#include <LibHTTP/HttpResponse.h>
|
||||
#include <LibHTTP/Job.h>
|
||||
@ -39,13 +39,13 @@ static ByteBuffer handle_content_encoding(const ByteBuffer& buf, const String& c
|
||||
dbgln_if(JOB_DEBUG, "Job::handle_content_encoding: buf has content_encoding={}", content_encoding);
|
||||
|
||||
if (content_encoding == "gzip") {
|
||||
if (!Core::Gzip::is_compressed(buf)) {
|
||||
if (!Compress::GzipDecompressor::is_likely_compressed(buf)) {
|
||||
dbgln("Job::handle_content_encoding: buf is not gzip compressed!");
|
||||
}
|
||||
|
||||
dbgln_if(JOB_DEBUG, "Job::handle_content_encoding: buf is gzip compressed!");
|
||||
|
||||
auto uncompressed = Core::Gzip::decompress(buf);
|
||||
auto uncompressed = Compress::GzipDecompressor::decompress_all(buf);
|
||||
if (!uncompressed.has_value()) {
|
||||
dbgln("Job::handle_content_encoding: Gzip::decompress() failed. Returning original buffer.");
|
||||
return buf;
|
||||
@ -352,6 +352,7 @@ void Job::finish_up()
|
||||
m_received_buffers.clear();
|
||||
|
||||
// For the time being, we cannot stream stuff with content-encoding set to _anything_.
|
||||
// FIXME: LibCompress exposes a streaming interface, so this can be resolved
|
||||
auto content_encoding = m_headers.get("Content-Encoding");
|
||||
if (content_encoding.has_value()) {
|
||||
flattened_buffer = handle_content_encoding(flattened_buffer, content_encoding.value());
|
||||
|
Loading…
Reference in New Issue
Block a user