/* sample of usage: see detection of VirtualBox in the table below to check registry path */
int vbox_reg_key7() {
    return pafish_exists_regkey(HKEY_LOCAL_MACHINE, "HARDWARE\\ACPI\\FADT\\VBOX__");
}

/* code is taken from "pafish" project, see references on the parent page */
int pafish_exists_regkey(HKEY hKey, char * regkey_s) {
    HKEY regkey;
    LONG ret;

    /* regkey_s == "HARDWARE\\ACPI\\FADT\\VBOX__"; */
    if (pafish_iswow64()) {
        ret = RegOpenKeyEx(hKey, regkey_s, 0, KEY_READ | KEY_WOW64_64KEY, &regkey);
    }
    else {
        ret = RegOpenKeyEx(hKey, regkey_s, 0, KEY_READ, &regkey);
    }

    if (ret == ERROR_SUCCESS) {
        RegCloseKey(regkey);
        return TRUE;
    }
    else
        return FALSE;
}

/* sample of usage: see detection of VirtualBox in the table below to check registry path and key values */
int vbox_reg_key2() {
    return pafish_exists_regkey_value_str(HKEY_LOCAL_MACHINE, "HARDWARE\\Description\\System", "SystemBiosVersion", "VBOX");
}

/* code is taken from "pafish" project, see references on the parent page */
int pafish_exists_regkey_value_str(HKEY hKey, char * regkey_s, char * value_s, char * lookup) {
    /*
        regkey_s == "HARDWARE\\Description\\System";
        value_s == "SystemBiosVersion";
        lookup == "VBOX";
    */

    HKEY regkey;
    LONG ret;
    DWORD size;
    char value[1024], * lookup_str;
    size_t lookup_size;

    lookup_size = strlen(lookup);
    lookup_str = malloc(lookup_size+sizeof(char));
    strncpy(lookup_str, lookup, lookup_size+sizeof(char));
    size = sizeof(value);

    /* regkey_s == "HARDWARE\\Description\\System"; */
    if (pafish_iswow64()) {
        ret = RegOpenKeyEx(hKey, regkey_s, 0, KEY_READ | KEY_WOW64_64KEY, &regkey);
    }
    else {
        ret = RegOpenKeyEx(hKey, regkey_s, 0, KEY_READ, &regkey);
    }

    if (ret == ERROR_SUCCESS) {
        /* value_s == "SystemBiosVersion"; */
        ret = RegQueryValueEx(regkey, value_s, NULL, NULL, (BYTE*)value, &size);
        RegCloseKey(regkey);

        if (ret == ERROR_SUCCESS) {
            size_t i;
            for (i = 0; i < strlen(value); i++) { /* case-insensitive */
                value[i] = toupper(value[i]);
            }
            for (i = 0; i < lookup_size; i++) { /* case-insensitive */
                lookup_str[i] = toupper(lookup_str[i]);
            }
            if (strstr(value, lookup_str) != NULL) {
                free(lookup_str);
                return TRUE;
            }
        }
    }

    free(lookup_str);
    return FALSE;
}