gistfile1.h

void
process_keystroke(int fd, short which, keyboard_t *kb)
{
    struct input_event input_event;
    ssize_t            bytes_read;
    char               key;

    bytes_read = read(fd, &input_event, sizeof(struct input_event));

    if (bytes_read != sizeof(struct input_event)) {
        fprintf(stderr, "[*] error reading device, ABORTING!\n");
        return;
    }

    /* make sure this is a keypress of some sort */
    if (input_event.type != EV_KEY) {
        return;
    }

    /* look for some things that may modify the next stroke */
    switch (input_event.code) {
        case KEY_RIGHTSHIFT:
        case KEY_LEFTSHIFT:
            kb->shift_mod = input_event.value;
            return;
        case KEY_RIGHTCTRL:
        case KEY_LEFTCTRL:
            /* I don't really care about ctrl chars */
            return;
        case KEY_CAPSLOCK:
            if (input_event.value == 1) {
                if (kb->caps_mod) {
                    kb->caps_mod = 0;
                } else {
                    kb->caps_mod = 1;
                }
            }
            return;
    }

    if (input_event.value != 1) {
        return;
    }

    if (input_event.code > sizeof(lowercase_map)) {
        return;
    }

    if (kb->shift_mod) {
        key = uppercase_map[input_event.code];

        if (kb->caps_mod) {
            key = tolower(key);
        }

    } else {
        key = lowercase_map[input_event.code];

        if (kb->caps_mod) {
            key = toupper(key);
        }
    }

    fprintf(stdout, "%c", key ? key : 0);
    fflush(stdout);

    return;
}