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/*
* Copyright (c) 2021, Idan Horowitz <idan.horowitz@gmail.com>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#pragma once
#include <AK/Function.h>
#include <AK/IterationDecision.h>
#include <AK/Span.h>
#include <AK/Stream.h>
#include <AK/String.h>
#include <AK/Vector.h>
#include <string.h>
namespace Archive {
// NOTE: Due to the format of zip files compression is streamed and decompression is random access.
static constexpr u8 end_of_central_directory_signature[] = { 0x50, 0x4b, 0x05, 0x06 }; // 'PK\x05\x06'
struct [[gnu::packed]] EndOfCentralDirectory {
u16 disk_number;
u16 central_directory_start_disk;
u16 disk_records_count;
u16 total_records_count;
u32 central_directory_size;
u32 central_directory_offset;
u16 comment_length;
const u8* comment;
bool read(ReadonlyBytes buffer)
{
auto fields_size = sizeof(EndOfCentralDirectory) - sizeof(u8*);
if (buffer.size() < sizeof(end_of_central_directory_signature) + fields_size)
return false;
if (memcmp(buffer.data(), end_of_central_directory_signature, sizeof(end_of_central_directory_signature)) != 0)
return false;
memcpy(reinterpret_cast<void*>(&disk_number), buffer.data() + sizeof(end_of_central_directory_signature), fields_size);
if (buffer.size() < sizeof(end_of_central_directory_signature) + fields_size + comment_length)
return false;
comment = buffer.data() + sizeof(end_of_central_directory_signature) + fields_size;
return true;
}
void write(OutputStream& stream) const
{
stream.write_or_error({ end_of_central_directory_signature, sizeof(end_of_central_directory_signature) });
stream << disk_number;
stream << central_directory_start_disk;
stream << disk_records_count;
stream << total_records_count;
stream << central_directory_size;
stream << central_directory_offset;
stream << comment_length;
if (comment_length > 0)
stream.write_or_error({ comment, comment_length });
}
};
static constexpr u8 central_directory_record_signature[] = { 0x50, 0x4b, 0x01, 0x02 }; // 'PK\x01\x02'
struct [[gnu::packed]] CentralDirectoryRecord {
u16 made_by_version;
u16 minimum_version;
u16 general_purpose_flags;
u16 compression_method;
u16 modification_time;
u16 modification_date;
u32 crc32;
u32 compressed_size;
u32 uncompressed_size;
u16 name_length;
u16 extra_data_length;
u16 comment_length;
u16 start_disk;
u16 internal_attributes;
u32 external_attributes;
u32 local_file_header_offset;
const u8* name;
const u8* extra_data;
const u8* comment;
bool read(ReadonlyBytes buffer)
{
auto fields_size = sizeof(CentralDirectoryRecord) - (sizeof(u8*) * 3);
if (buffer.size() < sizeof(central_directory_record_signature) + fields_size)
return false;
if (memcmp(buffer.data(), central_directory_record_signature, sizeof(central_directory_record_signature)) != 0)
return false;
memcpy(reinterpret_cast<void*>(&made_by_version), buffer.data() + sizeof(central_directory_record_signature), fields_size);
if (buffer.size() < sizeof(end_of_central_directory_signature) + fields_size + comment_length + name_length + extra_data_length)
return false;
name = buffer.data() + sizeof(central_directory_record_signature) + fields_size;
extra_data = name + name_length;
comment = extra_data + extra_data_length;
return true;
}
void write(OutputStream& stream) const
{
stream.write_or_error({ central_directory_record_signature, sizeof(central_directory_record_signature) });
stream << made_by_version;
stream << minimum_version;
stream << general_purpose_flags;
stream << compression_method;
stream << modification_time;
stream << modification_date;
stream << crc32;
stream << compressed_size;
stream << uncompressed_size;
stream << name_length;
stream << extra_data_length;
stream << comment_length;
stream << start_disk;
stream << internal_attributes;
stream << external_attributes;
stream << local_file_header_offset;
if (name_length > 0)
stream.write_or_error({ name, name_length });
if (extra_data_length > 0)
stream.write_or_error({ extra_data, extra_data_length });
if (comment_length > 0)
stream.write_or_error({ comment, comment_length });
}
[[nodiscard]] size_t size() const
{
return sizeof(central_directory_record_signature) + (sizeof(CentralDirectoryRecord) - (sizeof(u8*) * 3)) + name_length + extra_data_length + comment_length;
}
};
static constexpr u32 zip_directory_external_attribute = 1 << 4;
static constexpr u8 local_file_header_signature[] = { 0x50, 0x4b, 0x03, 0x04 }; // 'PK\x03\x04'
struct [[gnu::packed]] LocalFileHeader {
u16 minimum_version;
u16 general_purpose_flags;
u16 compression_method;
u16 modification_time;
u16 modification_date;
u32 crc32;
u32 compressed_size;
u32 uncompressed_size;
u16 name_length;
u16 extra_data_length;
const u8* name;
const u8* extra_data;
const u8* compressed_data;
bool read(ReadonlyBytes buffer)
{
auto fields_size = sizeof(LocalFileHeader) - (sizeof(u8*) * 3);
if (buffer.size() < sizeof(local_file_header_signature) + fields_size)
return false;
if (memcmp(buffer.data(), local_file_header_signature, sizeof(local_file_header_signature)) != 0)
return false;
memcpy(reinterpret_cast<void*>(&minimum_version), buffer.data() + sizeof(local_file_header_signature), fields_size);
if (buffer.size() < sizeof(end_of_central_directory_signature) + fields_size + name_length + extra_data_length + compressed_size)
return false;
name = buffer.data() + sizeof(local_file_header_signature) + fields_size;
extra_data = name + name_length;
compressed_data = extra_data + extra_data_length;
return true;
}
void write(OutputStream& stream) const
{
stream.write_or_error({ local_file_header_signature, sizeof(local_file_header_signature) });
stream << minimum_version;
stream << general_purpose_flags;
stream << compression_method;
stream << modification_time;
stream << modification_date;
stream << crc32;
stream << compressed_size;
stream << uncompressed_size;
stream << name_length;
stream << extra_data_length;
if (name_length > 0)
stream.write_or_error({ name, name_length });
if (extra_data_length > 0)
stream.write_or_error({ extra_data, extra_data_length });
if (compressed_size > 0)
stream.write_or_error({ compressed_data, compressed_size });
}
};
enum ZipCompressionMethod : u16 {
Store = 0,
Shrink = 1,
Reduce1 = 2,
Reduce2 = 3,
Reduce3 = 4,
Reduce4 = 5,
Implode = 6,
Reserved = 7,
Deflate = 8
};
struct ZipMember {
String name;
ReadonlyBytes compressed_data; // TODO: maybe the decompression/compression should be handled by LibArchive instead of the user?
ZipCompressionMethod compression_method;
u32 uncompressed_size;
u32 crc32;
bool is_directory;
};
class Zip {
public:
static Optional<Zip> try_create(const ReadonlyBytes& buffer);
bool for_each_member(Function<IterationDecision(const ZipMember&)>);
private:
static bool find_end_of_central_directory_offset(const ReadonlyBytes&, size_t& offset);
u16 member_count { 0 };
size_t members_start_offset { 0 };
ReadonlyBytes m_input_data;
};
class ZipOutputStream {
public:
ZipOutputStream(OutputStream&);
void add_member(const ZipMember&);
void finish();
private:
OutputStream& m_stream;
Vector<ZipMember> m_members;
bool m_finished { false };
};
}
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