ref: 9d7126c11b5f1577b00987b8d5f0f7f761b012d7
dir: /src/net_query.c/
// Emacs style mode select -*- C++ -*-
//-----------------------------------------------------------------------------
//
// Copyright(C) 2005 Simon Howard
//
// This program is free software; you can redistribute it and/or
// modify it under the terms of the GNU General Public License
// as published by the Free Software Foundation; either version 2
// of the License, or (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
// 02111-1307, USA.
//
// DESCRIPTION:
// Querying servers to find their current status.
//
#include <stdarg.h>
#include <stdlib.h>
#include "i_system.h"
#include "i_timer.h"
#include "net_common.h"
#include "net_defs.h"
#include "net_io.h"
#include "net_packet.h"
#include "net_query.h"
#include "net_structrw.h"
#include "net_sdl.h"
typedef struct
{
net_addr_t *addr;
net_querydata_t data;
} queryresponse_t;
static net_context_t *query_context;
static queryresponse_t *responders;
static int num_responses;
// Add a new address to the list of hosts that has responded
static queryresponse_t *AddResponder(net_addr_t *addr,
net_querydata_t *data)
{
queryresponse_t *response;
responders = realloc(responders,
sizeof(queryresponse_t) * (num_responses + 1));
response = &responders[num_responses];
response->addr = addr;
response->data = *data;
++num_responses;
return response;
}
// Returns true if the reply is from a host that has not previously
// responded.
static boolean CheckResponder(net_addr_t *addr)
{
int i;
for (i=0; i<num_responses; ++i)
{
if (responders[i].addr == addr)
{
return false;
}
}
return true;
}
// Transmit a query packet
static void NET_Query_SendQuery(net_addr_t *addr)
{
net_packet_t *request;
request = NET_NewPacket(10);
NET_WriteInt16(request, NET_PACKET_TYPE_QUERY);
if (addr == NULL)
{
NET_SendBroadcast(query_context, request);
}
else
{
NET_SendPacket(addr, request);
}
NET_FreePacket(request);
}
static void formatted_printf(int wide, char *s, ...)
{
va_list args;
int i;
va_start(args, s);
i = vprintf(s, args);
va_end(args);
while (i < wide)
{
putchar(' ');
++i;
}
}
static char *GameDescription(GameMode_t mode, GameMission_t mission)
{
switch (mode)
{
case shareware:
return "shareware";
case registered:
return "registered";
case retail:
return "ultimate";
case commercial:
if (mission == doom2)
return "doom2";
else if (mission == pack_tnt)
return "tnt";
else if (mission == pack_plut)
return "plutonia";
default:
return "unknown";
}
}
static void PrintHeader(void)
{
int i;
formatted_printf(18, "Address");
formatted_printf(8, "Players");
puts("Description");
for (i=0; i<70; ++i)
putchar('=');
putchar('\n');
}
static void PrintResponse(queryresponse_t *response)
{
formatted_printf(18, "%s: ", NET_AddrToString(response->addr));
formatted_printf(8, "%i/%i", response->data.num_players,
response->data.max_players);
if (response->data.gamemode != indetermined)
{
printf("(%s) ", GameDescription(response->data.gamemode,
response->data.gamemission));
}
if (response->data.server_state)
{
printf("(game running) ");
}
NET_SafePuts(response->data.description);
}
static void NET_Query_ParsePacket(net_addr_t *addr, net_packet_t *packet)
{
unsigned int packet_type;
net_querydata_t querydata;
queryresponse_t *response;
// Have we already received a packet from this host?
if (!CheckResponder(addr))
{
return;
}
// Read the header
if (!NET_ReadInt16(packet, &packet_type)
|| packet_type != NET_PACKET_TYPE_QUERY_RESPONSE)
{
return;
}
// Read query data
if (!NET_ReadQueryData(packet, &querydata))
{
return;
}
if (num_responses <= 0)
{
// If this is the first response, print the table header
PrintHeader();
}
response = AddResponder(addr, &querydata);
PrintResponse(response);
}
static void NET_Query_GetResponse(void)
{
net_addr_t *addr;
net_packet_t *packet;
if (NET_RecvPacket(query_context, &addr, &packet))
{
NET_Query_ParsePacket(addr, packet);
NET_FreePacket(packet);
}
}
static net_addr_t *NET_Query_QueryLoop(net_addr_t *addr,
boolean find_one)
{
int start_time;
int last_send_time;
last_send_time = -1;
start_time = I_GetTimeMS();
while (I_GetTimeMS() < start_time + 5000)
{
// Send a query once every second
if (last_send_time < 0 || I_GetTimeMS() > last_send_time + 1000)
{
NET_Query_SendQuery(addr);
last_send_time = I_GetTimeMS();
}
// Check for a response
NET_Query_GetResponse();
// Found a response?
if (find_one && num_responses > 0)
break;
// Don't thrash the CPU
I_Sleep(100);
}
if (num_responses > 0)
return responders[0].addr;
else
return NULL;
}
void NET_Query_Init(void)
{
query_context = NET_NewContext();
NET_AddModule(query_context, &net_sdl_module);
net_sdl_module.InitClient();
responders = NULL;
num_responses = 0;
}
void NET_QueryAddress(char *addr)
{
net_addr_t *net_addr;
NET_Query_Init();
net_addr = NET_ResolveAddress(query_context, addr);
if (net_addr == NULL)
{
I_Error("NET_QueryAddress: Host '%s' not found!", addr);
}
printf("\nQuerying '%s'...\n\n", addr);
if (!NET_Query_QueryLoop(net_addr, true))
{
I_Error("No response from '%s'", addr);
}
exit(0);
}
net_addr_t *NET_FindLANServer(void)
{
NET_Query_Init();
return NET_Query_QueryLoop(NULL, true);
}
void NET_LANQuery(void)
{
NET_Query_Init();
printf("\nSearching for servers on local LAN ...\n\n");
if (!NET_Query_QueryLoop(NULL, false))
{
I_Error("No servers found");
}
exit(0);
}