net_loop.c

/*  Copyright (C) 1996-1997 Id Software, Inc.
    Copyright (C) 1999-2012 other authors as noted in code comments

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 3 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.   */
// net_loop.c

#include "quakedef.h"
#include "net_loop.h"

qboolean	localconnectpending = false;
qsocket_t	*loop_client = NULL;
qsocket_t	*loop_server = NULL;

int Loop_Init (void)
{
    if (cls.state == ca_dedicated)
        return -1;
    return 0;
}


void Loop_Shutdown (void)
{
}


void Loop_Listen (qboolean state)
{
}


void Loop_SearchForHosts (qboolean xmit)
{
    if (!sv.active)
        return;

    hostCacheCount = 1;
    if (Q_strcmp(hostname.string, "UNNAMED") == 0)
        Q_strcpy(hostcache[0].name, "local");
    else
        Q_strcpy(hostcache[0].name, hostname.string);
    Q_strcpy(hostcache[0].map, sv.name);
    hostcache[0].users = net_activeconnections;
    hostcache[0].maxusers = svs.maxclients;
    hostcache[0].driver = net_driverlevel;
    Q_strcpy(hostcache[0].cname, "local");
}


qsocket_t *Loop_Connect (char *host)
{
    if (Q_strcmp(host,"local") != 0)
        return NULL;

    localconnectpending = true;

    if (!loop_client)
    {
        if ((loop_client = NET_NewQSocket ()) == NULL)
        {
            Con_Printf("Loop_Connect: no qsocket available\n");
            return NULL;
        }
        Q_strcpy (loop_client->address, "localhost");
    }
    loop_client->receiveMessageLength = 0;
    loop_client->sendMessageLength = 0;
    loop_client->canSend = true;

    if (!loop_server)
    {
        if ((loop_server = NET_NewQSocket ()) == NULL)
        {
            Con_Printf("Loop_Connect: no qsocket available\n");
            return NULL;
        }
        Q_strcpy (loop_server->address, "LOCAL");
    }
    loop_server->receiveMessageLength = 0;
    loop_server->sendMessageLength = 0;
    loop_server->canSend = true;

    loop_client->driverdata = (void *)loop_server;
    loop_server->driverdata = (void *)loop_client;

    return loop_client;
}


qsocket_t *Loop_CheckNewConnections (void)
{
    if (!localconnectpending)
        return NULL;

    localconnectpending = false;
    loop_server->sendMessageLength = 0;
    loop_server->receiveMessageLength = 0;
    loop_server->canSend = true;
    loop_client->sendMessageLength = 0;
    loop_client->receiveMessageLength = 0;
    loop_client->canSend = true;
    return loop_server;
}


static int IntAlign(int value)
{
    return (value + (sizeof(int) - 1)) & (~(sizeof(int) - 1));
}


int Loop_GetMessage (qsocket_t *sock)
{
    int		ret;
    int		length;

    if (sock->receiveMessageLength == 0)
        return 0;

    ret = sock->receiveMessage[0];
    length = sock->receiveMessage[1] + (sock->receiveMessage[2] << 8);
    // alignment byte skipped here
    SZ_Clear (&net_message);
    SZ_Write (&net_message, &sock->receiveMessage[4], length);

    length = IntAlign(length + 4);
    sock->receiveMessageLength -= length;

    if (sock->receiveMessageLength)
        memcpy(sock->receiveMessage, &sock->receiveMessage[length], sock->receiveMessageLength);

    if (sock->driverdata && ret == 1)
        ((qsocket_t *)sock->driverdata)->canSend = true;

    return ret;
}


int Loop_SendMessage (qsocket_t *sock, sizebuf_t *data)
{
    byte *buffer;
    unsigned int  *bufferLength;

    if (!sock->driverdata)
        return -1;

    bufferLength = &((qsocket_t *)sock->driverdata)->receiveMessageLength;

    if ((*bufferLength + data->cursize + 4) > NET_MAXMESSAGE)
        Sys_Error("Loop_SendMessage: overflow\n");

    buffer = ((qsocket_t *)sock->driverdata)->receiveMessage + *bufferLength;

    // message type
    *buffer++ = 1;

    // length
    *buffer++ = data->cursize & 0xff;
    *buffer++ = data->cursize >> 8;

    // align
    buffer++;

    // message
    memcpy(buffer, data->data, data->cursize);
    *bufferLength = IntAlign(*bufferLength + data->cursize + 4);

    sock->canSend = false;
    return 1;
}


int Loop_SendUnreliableMessage (qsocket_t *sock, sizebuf_t *data)
{
    byte *buffer;
    int  *bufferLength;

    if (!sock->driverdata)
        return -1;

    bufferLength = &((qsocket_t *)sock->driverdata)->receiveMessageLength;

    if ((*bufferLength + data->cursize + sizeof(byte) + sizeof(short)) > NET_MAXMESSAGE)
        return 0;

    buffer = ((qsocket_t *)sock->driverdata)->receiveMessage + *bufferLength;

    // message type
    *buffer++ = 2;

    // length
    *buffer++ = data->cursize & 0xff;
    *buffer++ = data->cursize >> 8;

    // align
    buffer++;

    // message
    memcpy(buffer, data->data, data->cursize);
    *bufferLength = IntAlign(*bufferLength + data->cursize + 4);
    return 1;
}


qboolean Loop_CanSendMessage (qsocket_t *sock)
{
    if (!sock->driverdata)
        return false;
    return sock->canSend;
}


qboolean Loop_CanSendUnreliableMessage (qsocket_t *sock)
{
    return true;
}


void Loop_Close (qsocket_t *sock)
{
    if (sock->driverdata)
        ((qsocket_t *)sock->driverdata)->driverdata = NULL;
    sock->receiveMessageLength = 0;
    sock->sendMessageLength = 0;
    sock->canSend = true;
    if (sock == loop_client)
        loop_client = NULL;
    else
        loop_server = NULL;
}