bsnes/nall/encode/zip.hpp

102 lines
3.8 KiB
C++

#pragma once
//creates uncompressed ZIP archives
#include <nall/string.hpp>
#include <nall/hash/crc32.hpp>
namespace nall { namespace Encode {
struct ZIP {
ZIP(const string& filename) {
fp.open(filename, file::mode::write);
timestamp = time(nullptr);
}
//append path: append("path/");
//append file: append("path/file", data, size);
auto append(string filename, const uint8_t* data = nullptr, uint size = 0u, time_t timestamp = 0) -> void {
filename.transform("\\", "/");
if(!timestamp) timestamp = this->timestamp;
uint32_t checksum = Hash::CRC32(data, size).digest().hex();
directory.append({filename, timestamp, checksum, size, fp.offset()});
fp.writel(0x04034b50, 4); //signature
fp.writel(0x0014, 2); //minimum version (2.0)
fp.writel(0x0000, 2); //general purpose bit flags
fp.writel(0x0000, 2); //compression method (0 = uncompressed)
fp.writel(makeTime(timestamp), 2);
fp.writel(makeDate(timestamp), 2);
fp.writel(checksum, 4);
fp.writel(size, 4); //compressed size
fp.writel(size, 4); //uncompressed size
fp.writel(filename.length(), 2); //file name length
fp.writel(0x0000, 2); //extra field length
fp.print(filename); //file name
fp.write(data, size); //file data
}
~ZIP() {
//central directory
uint baseOffset = fp.offset();
for(auto& entry : directory) {
fp.writel(0x02014b50, 4); //signature
fp.writel(0x0014, 2); //version made by (2.0)
fp.writel(0x0014, 2); //version needed to extract (2.0)
fp.writel(0x0000, 2); //general purpose bit flags
fp.writel(0x0000, 2); //compression method (0 = uncompressed)
fp.writel(makeTime(entry.timestamp), 2);
fp.writel(makeDate(entry.timestamp), 2);
fp.writel(entry.checksum, 4);
fp.writel(entry.size, 4); //compressed size
fp.writel(entry.size, 4); //uncompressed size
fp.writel(entry.filename.length(), 2); //file name length
fp.writel(0x0000, 2); //extra field length
fp.writel(0x0000, 2); //file comment length
fp.writel(0x0000, 2); //disk number start
fp.writel(0x0000, 2); //internal file attributes
fp.writel(0x00000000, 4); //external file attributes
fp.writel(entry.offset, 4); //relative offset of file header
fp.print(entry.filename);
}
uint finishOffset = fp.offset();
//end of central directory
fp.writel(0x06054b50, 4); //signature
fp.writel(0x0000, 2); //number of this disk
fp.writel(0x0000, 2); //disk where central directory starts
fp.writel(directory.size(), 2); //number of central directory records on this disk
fp.writel(directory.size(), 2); //total number of central directory records
fp.writel(finishOffset - baseOffset, 4); //size of central directory
fp.writel(baseOffset, 4); //offset of central directory
fp.writel(0x0000, 2); //comment length
fp.close();
}
protected:
auto makeTime(time_t timestamp) -> uint16_t {
tm* info = localtime(&timestamp);
return (info->tm_hour << 11) | (info->tm_min << 5) | (info->tm_sec >> 1);
}
auto makeDate(time_t timestamp) -> uint16_t {
tm* info = localtime(&timestamp);
return ((info->tm_year - 80) << 9) | ((1 + info->tm_mon) << 5) + (info->tm_mday);
}
file fp;
time_t timestamp;
struct entry_t {
string filename;
time_t timestamp;
uint32_t checksum;
uint32_t size;
uint32_t offset;
};
vector<entry_t> directory;
};
}}