/*---------------------------------------------------
called when the window received WSOCK_SELECT.
receive SNTP data and set time.
---------------------------------------------------*/
void OnReceive(HWND hwnd, WPARAM wParam, LPARAM lParam)
{
struct sockaddr_in serversockaddr;
struct NTP_Packet NTP_Recv;
int sockaddr_Size;
if(g_socket == -1) return;
if(WSAGETSELECTERROR(lParam))
{
SocketClose(hwnd, "failed to receive");
return;
}
if(g_socket != (int)wParam ||
WSAGETSELECTEVENT(lParam) != FD_READ) return;
// receive data
sockaddr_Size = sizeof(serversockaddr);
if(recvfrom(g_socket, (char *)&NTP_Recv, sizeof(NTP_Recv), 0,
(struct sockaddr *)&serversockaddr, &sockaddr_Size) == SOCKET_ERROR)
{
SocketClose(hwnd, "recvfrom() failed");
return;
}
// if Leap Indicator is 3
/*
if(ntohl(NTP_Recv.Control_Word) >> 30 == 3)
{
SocketClose(hwnd, "server is unhealthy");
return;
}
*/
// set system time
SynchronizeSystemTime(ntohl(NTP_Recv.transmit_timestamp_seconds),
ntohl(NTP_Recv.transmit_timestamp_fractions));
// close socket
SocketClose(hwnd, NULL);
}
/*---------------------------------------------------
called when the window received WSOCK_SELECT.
receive SNTP data and set time.
---------------------------------------------------*/
void OnReceive(HWND hwndSNTP, WPARAM wParam, LPARAM lParam)
{
struct sockaddr_in serversockaddr;
struct NTP_Packet NTP_Recv;
int sockaddr_Size;
if(m_socket == INVALID_SOCKET) return;
if(WSAGETSELECTERROR(lParam))
{
SocketClose(hwndSNTP, "failed to receive");
return;
}
if(m_socket != (SOCKET)wParam ||
WSAGETSELECTEVENT(lParam) != FD_READ) return;
// receive data
m_dwTickCountOnRecv = timeGetTime();
sockaddr_Size = sizeof(serversockaddr);
if(recvfrom(m_socket, (char *)&NTP_Recv, sizeof(NTP_Recv), 0,
(struct sockaddr *)&serversockaddr, &sockaddr_Size) == SOCKET_ERROR)
{
SocketClose(hwndSNTP, "recvfrom() failed");
return;
}
// if Leap Indicator is 3
if((NTP_Recv.Control_Byte >> 6) == 3)
{
SocketClose(hwndSNTP, "server is unhealthy");
return;
}
// set system time
SynchronizeSystemTime(hwndSNTP, &NTP_Recv);
// close socket
SocketClose(hwndSNTP, NULL);
}
