bsnes/nall/decode/zip.hpp

137 lines
3.2 KiB
C++

#pragma once
#include <nall/file-map.hpp>
#include <nall/string.hpp>
#include <nall/vector.hpp>
#include <nall/decode/inflate.hpp>
namespace nall::Decode {
struct ZIP {
struct File {
string name;
const uint8_t* data;
uint size;
uint csize;
uint cmode; //0 = uncompressed, 8 = deflate
uint crc32;
time_t timestamp;
};
~ZIP() {
close();
}
auto open(const string& filename) -> bool {
close();
if(fm.open(filename, file::mode::read) == false) return false;
if(open(fm.data(), fm.size()) == false) {
fm.close();
return false;
}
return true;
}
auto open(const uint8_t* data, uint size) -> bool {
if(size < 22) return false;
filedata = data;
filesize = size;
file.reset();
const uint8_t* footer = data + size - 22;
while(true) {
if(footer <= data + 22) return false;
if(read(footer, 4) == 0x06054b50) {
uint commentlength = read(footer + 20, 2);
if(footer + 22 + commentlength == data + size) break;
}
footer--;
}
const uint8_t* directory = data + read(footer + 16, 4);
while(true) {
uint signature = read(directory + 0, 4);
if(signature != 0x02014b50) break;
File file;
file.cmode = read(directory + 10, 2);
file.crc32 = read(directory + 16, 4);
file.csize = read(directory + 20, 4);
file.size = read(directory + 24, 4);
uint16_t dosTime = read(directory + 12, 2);
uint16_t dosDate = read(directory + 14, 2);
tm info = {};
info.tm_sec = (dosTime >> 0 & 31) << 1;
info.tm_min = (dosTime >> 5 & 63);
info.tm_hour = (dosTime >> 11 & 31);
info.tm_mday = (dosDate >> 0 & 31);
info.tm_mon = (dosDate >> 5 & 15) - 1;
info.tm_year = (dosDate >> 9 & 127) + 80;
info.tm_isdst = -1;
file.timestamp = mktime(&info);
uint namelength = read(directory + 28, 2);
uint extralength = read(directory + 30, 2);
uint commentlength = read(directory + 32, 2);
char* filename = new char[namelength + 1];
memcpy(filename, directory + 46, namelength);
filename[namelength] = 0;
file.name = filename;
delete[] filename;
uint offset = read(directory + 42, 4);
uint offsetNL = read(data + offset + 26, 2);
uint offsetEL = read(data + offset + 28, 2);
file.data = data + offset + 30 + offsetNL + offsetEL;
directory += 46 + namelength + extralength + commentlength;
this->file.append(file);
}
return true;
}
auto extract(File& file) -> vector<uint8_t> {
vector<uint8_t> buffer;
if(file.cmode == 0) {
buffer.resize(file.size);
memcpy(buffer.data(), file.data, file.size);
}
if(file.cmode == 8) {
buffer.resize(file.size);
if(inflate(buffer.data(), buffer.size(), file.data, file.csize) == false) {
buffer.reset();
}
}
return buffer;
}
auto close() -> void {
if(fm) fm.close();
}
protected:
file_map fm;
const uint8_t* filedata;
uint filesize;
auto read(const uint8_t* data, uint size) -> uint {
uint result = 0, shift = 0;
while(size--) { result |= *data++ << shift; shift += 8; }
return result;
}
public:
vector<File> file;
};
}