Files
2023-04-22 15:16:21 +02:00

104 lines
2.3 KiB
C++

#include <vector>
#include <string>
#include <iostream> // std::cout
#include <fstream> // ifstream, ofstream
#include <libgen.h> // basename()
#include <iterator>
using namespace std;
string filePath = "";
vector<unsigned char> buffer;
int desp = 0x2000;
int numBytes = 0x2000;
int firstByte = desp + 0x200;
int lastByte = desp + numBytes - 1;
int checksum1 = desp + 0x270;
int checksum2 = desp + 0x271;
void checkParameters(int argc, char *argv[])
{
if (argc != 2)
{
cout << "Uso: " << basename(argv[0]) << " FILE" << endl;
exit(EXIT_FAILURE);
}
else
filePath = argv[1];
}
void loadFile(string s)
{
ifstream inputFile(s, ios::binary);
if (inputFile.good())
buffer.assign(istreambuf_iterator<char>(inputFile), {});
else
{
cout << "No se puede abrir el archivo: " << s << endl;
exit(EXIT_FAILURE);
}
inputFile.close();
}
void saveFile(string s)
{
ofstream outputFile(s, ios::binary);
if (outputFile.good())
{
for (auto i : buffer)
{
outputFile << i;
}
cout << "Fichero guardado: " << s << endl;
}
else
{
cout << "No se puede abrir el archivo: " << s << endl;
exit(EXIT_FAILURE);
}
outputFile.close();
}
void printBuffer()
{
int count = 0;
for (auto i : buffer)
{
cout << static_cast<unsigned>(i) << " ";
count++;
if (count % 16 == 0)
cout << static_cast<unsigned>(i) << endl;
}
}
int calcChecksum()
{
int sum = 0;
for (int i = firstByte; i <= lastByte; i++)
{
if (i != checksum1 and i != checksum2)
sum += static_cast<unsigned>(buffer.at(i));
}
sum += 3328; // Corrige el checksum
buffer.at(checksum1) = sum % 256;
buffer.at(checksum2) = (sum >> 8) % 256;
return sum;
}
int main(int argc, char *argv[])
{
checkParameters(argc, argv);
loadFile(filePath);
saveFile(filePath + ".bak");
calcChecksum();
saveFile(filePath);
//cout << hex;
//cout << "0x" << checksum1 << ": 0x" << static_cast<unsigned>(buffer.at(checksum1)) << endl;
//cout << "0x" << checksum2 << ": 0x" << static_cast<unsigned>(buffer.at(checksum2)) << endl;
//cout << "checksum (0x" << firstByte << " .. 0x" << lastByte << "): 0x" << sum << endl;
return 0;
}