/*!
* main loop. Accept contribution from clients and dispatch digest of
* the frame to all clients
*/
void
serve_dispatch (global_option_type * global_option)
{
global_status_type global_status;
int client_index;
/*
* Initialize global_status fields
*/
global_status.frame_number = 1;
global_status.number_identified_players = 0;
global_status.number_allocation_request = 0;
#if defined(GTK)
gtk_stop_asked = 0;
#endif
for (client_index = 0; client_index < MAX_NUMBER_PLAYER; client_index++)
{
global_status.player_status[client_index] = UNIDENTIFIED;
}
global_status.server_socket = SDLNet_UDP_Open (global_option->server_port);
if (global_status.server_socket == NULL)
{
printf_screen ("Couldn't open UDP socket on port %d.\nCheck privileges and availability.\n",
global_option->server_port);
return;
}
/* global_status.server_socket is ready to serve our needs :) */
global_status.current_packet = SDLNet_AllocPacket (CLIENT_PACKET_SIZE);
if (global_status.current_packet == NULL)
{
SDLNet_UDP_Close (global_status.server_socket);
printf_screen ("Failed to allocate a buffer for receiving client packets (size: %d bytes) (Not enough memory ?)",
CLIENT_PACKET_SIZE);
return;
}
global_status.digest_packet = SDLNet_AllocPacket (SERVER_PACKET_SIZE);
if (global_status.digest_packet == NULL)
{
SDLNet_UDP_Close (global_status.server_socket);
SDLNet_FreePacket (global_status.digest_packet);
printf_screen ("Failed to allocate a buffer for sending packets (size: %d bytes) (Not enough memory ?)",
SERVER_PACKET_SIZE);
return;
}
/* Allocate enough space for a single socket */
global_status.server_socket_set = SDLNet_AllocSocketSet (1);
if (global_status.server_socket_set == NULL)
{
SDLNet_UDP_Close (global_status.server_socket);
SDLNet_FreePacket (global_status.current_packet);
SDLNet_FreePacket (global_status.digest_packet);
printf_screen ("Couldn't allocate a socket set (not enough memory ?).\n");
return;
}
if (SDLNet_UDP_AddSocket (global_status.server_socket_set, global_status.server_socket) !=
1)
{
SDLNet_UDP_Close (global_status.server_socket);
SDLNet_FreePacket (global_status.current_packet);
SDLNet_FreePacket (global_status.digest_packet);
SDLNet_FreeSocketSet (global_status.server_socket_set);
printf_screen ("Error when adding socket to socket set.\n");
return;
}
/* Identification loop */
/*
* We're expecting identification packets until we've filled all slots, then
* we can proceed to the real meat
*/
for (;;)
{
int number_ready_socket;
#if defined(DEBUG)
printf_screen ("Waiting for identification\n");
#endif
if (read_incoming_server_packet (&global_status))
{
identify_client (&global_status, global_option);
if (count_remaining_slot (&global_status, global_option) == 0)
{
/* Perfect, we've finished the identification of all slots */
break;
}
printf_screen("%d slots open.\n", count_remaining_slot (&global_status, global_option));
/* Going back to the identification loop */
continue;
}
#if defined(GTK)
gtk_iteration = GTK_SERVER_SOCKET_RATIO;
do {
number_ready_socket =
SDLNet_CheckSockets (global_status.server_socket_set, SERVER_SOCKET_TIMEOUT / GTK_SERVER_SOCKET_RATIO);
while (gtk_events_pending())
{
if (gtk_main_iteration())
{
gtk_stop_asked = 1;
}
}
} while ( (number_ready_socket == 0) && (--gtk_iteration != 0) && !gtk_stop_asked);
#else
number_ready_socket =
SDLNet_CheckSockets (global_status.server_socket_set, SERVER_SOCKET_TIMEOUT);
#endif
if (gtk_stop_asked)
{
break;
}
if (number_ready_socket == -1)
{
printf_screen ("Error in socket waiting (disconnection ?).\n");
break;
}
if (number_ready_socket == 1)
{
#if defined(DEBUG)
printf_screen ("Got a packet\n");
#endif
/* We're awaiting a packet in the server socket */
if (read_incoming_server_packet (&global_status))
{
/*
* If we haven't identified all clients yet, we're trying to use the current packet
* to improve our knowledge of the typography
*/
identify_client (&global_status, global_option);
if (count_remaining_slot (&global_status, global_option) == 0)
{
/* Perfect, we've finished the identification of all slots */
break;
}
printf_screen("%d slots open.\n", count_remaining_slot (&global_status, global_option));
}
}
}
if (!gtk_stop_asked)
{
printf_screen ("Identification finished\n");
#if defined(DEBUG)
for (client_index = 0; client_index < MAX_NUMBER_PLAYER; client_index++)
{
printf_screen ("Mapping[%d] = { { 0x%08X, %d }, %d }\n", client_index,
global_status.input_mapping[client_index].address.host,
global_status.input_mapping[client_index].address.port,
global_status.input_mapping[client_index].remote_input_device);
}
#endif
switch (global_option->type_server)
{
case LAN_PROTOCOL_TYPE:
serve_clients_lan_protocol(&global_status, global_option);
break;
case INTERNET_PROTOCOL_TYPE:
serve_clients_internet_protocol(&global_status, global_option);
break;
default:
printf_screen("Internal error, unknown internal server type : %d\n", global_option->type_server);
break;
}
} // gtk_stop_asked
/*
* Free resources
*/
SDLNet_FreePacket (global_status.current_packet);
SDLNet_FreePacket (global_status.digest_packet);
SDLNet_FreeSocketSet (global_status.server_socket_set);
SDLNet_UDP_Close (global_status.server_socket);
global_status.server_socket = NULL;
}
/*!
* Process an identification request from a client, filling the interesting
* fields in the global_status structure to find later the client
*/
void
identify_client (global_status_type * global_status,
global_option_type * global_option)
{
int requested_slots;
int allocated_slots;
int slot_index;
int already_allocated_slot_by_client;
if (global_status->current_packet->len != PACKET_IDENTIFICATION_LENGTH)
{
/* Discarding invalid packet */
#if defined(DEBUG)
fprintf (stderr,
"Invalid packet received when in identification phase (received length: %d, expected length: %d)\n",
global_status->current_packet->len,
PACKET_IDENTIFICATION_LENGTH);
#endif
return;
}
if (global_status->current_packet->data[PACKET_IDENTIFIER] !=
PACKET_IDENTIFICATION_ID)
{
/* Discarding invalid packet */
#if defined(DEBUG)
fprintf (stderr,
"Invalid packet received when in identification phase (received ID: 0x%02x, expected ID: 0x%02x)\n",
global_status->current_packet->data[PACKET_IDENTIFIER],
PACKET_IDENTIFICATION_ID);
#endif
return;
}
if (global_status->current_packet->data[PACKET_IDENTIFICATION_CHECKSUM] !=
compute_checksum (global_status->current_packet->data,
PACKET_IDENTIFIER, PACKET_IDENTIFICATION_CHECKSUM))
{
/* Discarding invalid packet */
#if defined(DEBUG)
fprintf (stderr,
"Packet checksum received when in identification phase (received checksum: 0x%02x, expected checksum: 0x%02x)\n",
global_status->current_packet->
data[PACKET_IDENTIFICATION_CHECKSUM],
compute_checksum (global_status->current_packet->data,
PACKET_IDENTIFIER,
PACKET_IDENTIFICATION_CHECKSUM));
#endif
return;
}
requested_slots =
global_status->current_packet->
data[PACKET_IDENTIFICATION_NUMBER_REQUESTED_SLOTS];
allocated_slots =
min (requested_slots,
count_remaining_slot (global_status, global_option));
/* Check if it's a new request or a re-request (happens when the client didn't get the acknowledgement) */
already_allocated_slot_by_client =
compare_request_to_previous (global_status,
global_status->current_packet->address);
if (already_allocated_slot_by_client != -1)
{
/* We already answered this client, we'll reacknowledge */
send_identification_acknowledge_packet (global_status,
already_allocated_slot_by_client);
return;
}
for (slot_index = global_status->number_identified_players;
slot_index <
global_status->number_identified_players + allocated_slots;
slot_index++)
{
/* Set the address for identified player */
global_status->input_mapping[slot_index].address.port =
global_status->current_packet->address.port;
global_status->input_mapping[slot_index].address.host =
global_status->current_packet->address.host;
/* Set the remote input device number */
global_status->input_mapping[slot_index].remote_input_device =
global_status->current_packet->
data[PACKET_IDENTIFICATION_INPUT_DEVICE_INDEX + slot_index -
global_status->number_identified_players];
/* Change status from UNIDENTIFIED */
global_status->player_status[slot_index] = WAITING;
}
global_status->allocation_request[global_status->number_allocation_request].
address.port = global_status->current_packet->address.port;
global_status->allocation_request[global_status->number_allocation_request].
address.host = global_status->current_packet->address.host;
global_status->allocation_request[global_status->number_allocation_request].
allocated_slots = allocated_slots;
global_status->number_allocation_request++;
global_status->number_identified_players += allocated_slots;
send_identification_acknowledge_packet (global_status, allocated_slots);
}