/**

 * vim: set ts=4 :

 * =============================================================================

 * SourceMod SDKTools Extension

 * Copyright (C) 2004-2008 AlliedModders LLC.  All rights reserved.

 * =============================================================================

 *

 * This program is free software; you can redistribute it and/or modify it under

 * the terms of the GNU General Public License, version 3.0, as published by the

 * Free Software Foundation.

 * 

 * 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, see <http://www.gnu.org/licenses/>.

 *

 * As a special exception, AlliedModders LLC gives you permission to link the

 * code of this program (as well as its derivative works) to "Half-Life 2," the

 * "Source Engine," the "SourcePawn JIT," and any Game MODs that run on software

 * by the Valve Corporation.  You must obey the GNU General Public License in

 * all respects for all other code used.  Additionally, AlliedModders LLC grants

 * this exception to all derivative works.  AlliedModders LLC defines further

 * exceptions, found in LICENSE.txt (as of this writing, version JULY-31-2007),

 * or <http://www.sourcemod.net/license.php>.

 *

 * Version: $Id$

 */

#include "extension.h"

void **g_pGameRules = NULL;

void *g_EntList = NULL;

#ifdef PLATFORM_WINDOWS

void InitializeValveGlobals()

{

	char *addr = NULL;

	int offset;

	/* gEntList and/or g_pEntityList */

	if (!g_pGameConf->GetMemSig("LevelShutdown", (void **)&addr) || !addr)

	{

		return;

	}

	if (!g_pGameConf->GetOffset("gEntList", &offset) || !offset)

	{

		return;

	}

	g_EntList = *reinterpret_cast<void **>(addr + offset);

	/* g_pGameRules */

	if (!g_pGameConf->GetMemSig("CreateGameRulesObject", (void **)&addr) || !addr)

	{

		return;

	}

	if (!g_pGameConf->GetOffset("g_pGameRules", &offset) || !offset)

	{

		return;

	}

	g_pGameRules = *reinterpret_cast<void ***>(addr + offset);

}

#elif defined PLATFORM_LINUX

void InitializeValveGlobals()

{

	char *addr = NULL;

	/* gEntList and/or g_pEntityList */

	if (!g_pGameConf->GetMemSig("gEntList", (void **)&addr) || !addr)

	{

		return;

	}

	g_EntList = reinterpret_cast<void *>(addr);

	/* g_pGameRules */

	if (!g_pGameConf->GetMemSig("g_pGameRules", (void **)&addr) || !addr)

	{

		return;

	}

	g_pGameRules = reinterpret_cast<void **>(addr);

}

#endif

bool vcmp(const void *_addr1, const void *_addr2, size_t len)

{

	unsigned char *addr1 = (unsigned char *)_addr1;

	unsigned char *addr2 = (unsigned char *)_addr2;

	for (size_t i=0; i<len; i++)

	{

		if (addr2[i] == '*')

			continue;

		if (addr1[i] != addr2[i])

			return false;

	}

	return true;

}

#if defined PLATFORM_WINDOWS

	/* Thanks to DS for the sigs */

	#define ISERVER_WIN_SIG				"\x8B\x44\x24\x2A\x50\xB9\x2A\x2A\x2A\x2A\xE8"

	#define ISERVER_WIN_SIG_LEN			11

void GetIServer()

{

	int offset;

	void *vfunc = NULL;

	/* Get the offset into CreateFakeClient */

	if (!g_pGameConf->GetOffset("sv", &offset))

	{

		return;

	}

#if defined METAMOD_PLAPI_VERSION

	/* Get the CreateFakeClient function pointer */

	if (!(vfunc=SH_GET_ORIG_VFNPTR_ENTRY(engine, &IVEngineServer::CreateFakeClient)))

	{

		return;

	}

	/* Check if we're on the expected function */

	if (!vcmp(vfunc, ISERVER_WIN_SIG, ISERVER_WIN_SIG_LEN))

	{

		return;

	}

	/* Finally we have the interface we were looking for */

	iserver = *reinterpret_cast<IServer **>(reinterpret_cast<unsigned char *>(vfunc) + offset);

#else

	/* Get the interface manually */

	SourceHook::MemFuncInfo info = {true, -1, 0, 0};

	SourceHook::GetFuncInfo(&IVEngineServer::CreateFakeClient, info);

	vfunc = enginePatch->GetOrigFunc(info.vtbloffs, info.vtblindex);

	if (!vfunc)

	{

		void **vtable = *reinterpret_cast<void ***>(enginePatch->GetThisPtr() + info.thisptroffs + info.vtbloffs);

		vfunc = vtable[info.vtblindex];

	}

	/* Check if we're on the expected function */

	if (!vcmp(vfunc, ISERVER_WIN_SIG, ISERVER_WIN_SIG_LEN))

	{

		return;

	}

	iserver = *reinterpret_cast<IServer **>(reinterpret_cast<unsigned char *>(vfunc) + offset);

#endif

}

#elif defined PLATFORM_POSIX

void GetIServer()

{

	void *addr;

	if (!g_pGameConf->GetMemSig("sv", &addr) || !addr)

	{

		return;

	}

	iserver = reinterpret_cast<IServer *>(addr);

}

#endif