bsnes/nall/unzip.hpp

127 lines
2.8 KiB
C++

#ifndef NALL_UNZIP_HPP
#define NALL_UNZIP_HPP
#include <nall/filemap.hpp>
#include <nall/inflate.hpp>
#include <nall/string.hpp>
#include <nall/vector.hpp>
namespace nall {
struct unzip {
struct File {
string name;
const uint8_t* data;
unsigned size;
unsigned csize;
unsigned cmode; //0 = uncompressed, 8 = deflate
unsigned crc32;
};
inline bool open(const string& filename) {
close();
if(fm.open(filename, filemap::mode::read) == false) return false;
if(open(fm.data(), fm.size()) == false) {
fm.close();
return false;
}
return true;
}
inline bool open(const uint8_t* data, unsigned size) {
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) {
unsigned commentlength = read(footer + 20, 2);
if(footer + 22 + commentlength == data + size) break;
}
footer--;
}
const uint8_t* directory = data + read(footer + 16, 4);
while(true) {
unsigned 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);
unsigned namelength = read(directory + 28, 2);
unsigned extralength = read(directory + 30, 2);
unsigned commentlength = read(directory + 32, 2);
char* filename = new char[namelength + 1];
memcpy(filename, directory + 46, namelength);
filename[namelength] = 0;
file.name = filename;
delete[] filename;
unsigned offset = read(directory + 42, 4);
unsigned offsetNL = read(data + offset + 26, 2);
unsigned offsetEL = read(data + offset + 28, 2);
file.data = data + offset + 30 + offsetNL + offsetEL;
directory += 46 + namelength + extralength + commentlength;
this->file.append(file);
}
return true;
}
inline vector<uint8_t> extract(File& file) {
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;
}
inline void close() {
if(fm.open()) fm.close();
}
~unzip() {
close();
}
protected:
filemap fm;
const uint8_t* filedata;
unsigned filesize;
unsigned read(const uint8_t* data, unsigned size) {
unsigned result = 0, shift = 0;
while(size--) { result |= *data++ << shift; shift += 8; }
return result;
}
public:
vector<File> file;
};
}
#endif