pass

main.cpp

#include <iostream>
#include <termios.h>
#include <unistd.h>

using namespace std;

// no conio on linux
// thanks AI
// This function manually implements the logic of getch() on Linux
char getch()
{
    char buf = 0;
    struct termios old = {0};
    if (tcgetattr(0, &old) < 0)
        perror("tcsetattr()");
    old.c_lflag &= ~ICANON; // Disable buffered I/O
    old.c_lflag &= ~ECHO;   // Disable echo
    old.c_cc[VMIN] = 1;
    old.c_cc[VTIME] = 0;
    if (tcsetattr(0, TCSANOW, &old) < 0)
        perror("tcsetattr ICANON");
    if (read(0, &buf, 1) < 0)
        perror("read()");
    old.c_lflag |= ICANON; // Restore buffered I/O
    old.c_lflag |= ECHO;   // Restore echo
    if (tcsetattr(0, TCSADRAIN, &old) < 0)
        perror("tcsetattr ~ICANON");
    return (buf);
}

int main()
{
    cout << "Enter password: " << flush;
    char *right_pass = "1234";
    int right_len = 4;

    char *pass = new char;
    char c = 0;
    int idx = 0;

    while (true)
    {
        c = getch();

        if (c == '\n')
        {
            break;
        }

        cout << "*" << flush;

        pass[idx] = c;
        idx++;
    }

    cout << endl;

    int len = 0;
    while (*pass != NULL)
    {
        pass++;
        len++;
    }

    for (int i = len; i > 0; i--)
    {
        pass--;
    }

    bool verified = true;
    // validate
    if (right_len == len)
    {
        while (*pass != NULL)
        {
            if (*pass != *right_pass)
            {
                verified = false;
            }

            pass++;
            right_pass++;
        }
    }
    else
    {
        verified = false;
    }

    cout << "Verified: " << (verified ? "true" : "false") << endl;

    return 0;
}