// Copyright (c) 2004-2009 Nokia Corporation and/or its subsidiary(-ies).

// All rights reserved.

// This component and the accompanying materials are made available

// under the terms of "Eclipse Public License v1.0"

// which accompanies this distribution, and is available

// at the URL "http://www.eclipse.org/legal/epl-v10.html".

//

// Initial Contributors:

// Nokia Corporation - initial contribution.

//

// Contributors:

//

// Description:

// engine.cpp - name resolver core engine

//

#include "dnd.hrh"

#include "engine.h"

#include "listener.h"

#include "dnd_ini.h"

#include "inet6log.h"

#include <es_ini.h>

#include <timeout.h>

#include "in6_version.h"

//

MDemonEngine *MDemonEngine::NewL(MDemonMain &aMain)

	/**

	* Create the instance of CDndEngine.

	* There can only be one of these.

	* @param aMain The DLL/EXE "main" interface

	* @return The Engine interface

	*/

	{

	return new (ELeave) CDndEngine(aMain);

	}

//

CDndEngine::~CDndEngine()

	{

	//

	// Ordering is important... Do not close iSS before

	// all sockets associated with it have been closed!

	//

	iHostsFile.Close();

	delete iListener;

	delete iConfig;

	delete iTimer;

	iSocket.Close();

	iFS.Close();

	iSS.Close();

	}

TInt CDndEngine::GetIniValue(const TDesC &aSection, const TDesC &aName, TInt aDefault, TInt aMin, TInt aMax)

	/**

	* Read an integer value from the INI file.

	*

	* The INI is a text file (currently named by #DND_INI_DATA).

	* The used sections are [resolver] and [llmnr]

	*

	* @param aSection The INI section name

	* @param aName The INI variable name

	* @param aDefault The value returned if variable name not found or is out of range

	* @param aMin The min of the accepted range

	* @param aMax The max of the accepted range

	*/

	{

	LOG(_LIT(KFormat, "\t[%S] %S = %d"));

	LOG(_LIT(KFormatInv, "\t[%S] %S = %d is invalid"));

	TInt value;

	if (!FindVar(aSection, aName, value))

		value = aDefault;

	else if (value < aMin || value > aMax)

		{

		LOG(Log::Printf(KFormatInv, &aSection, &aName, value));

		value = aDefault;

		}

	LOG(Log::Printf(KFormat, &aSection, &aName, value));

	return value;

	}

void CDndEngine::GetIniAddress(const TDesC &aSection, const TDesC &aName, const TDesC &aDefault, TIp6Addr &aAddr)

	/**

	* Read an address value from the INI file.

	*

	* The INI is a text file (currently named by #DND_INI_DATA).

	* The currently used sections are [resolver] and [llmnr].

	*

	* The default is used if INI file does not specify address or the specified

	* address is not syntactically correct. If the default is also bad, the

	* aAddr will be unspecified.

	*

	* @param aSection The INI section name

	* @param aName The INI variable name

	* @param aDefault The default value for the variable (string format)

	* @retval aAddr The address

	*/

	{

	TInetAddr addr;

	TPtrC str;

	if (!FindVar(aSection, aName, str))

		str.Set(aDefault);

	const TInt value = addr.Input(str);

	// If the parameter is bad, then use the aDefault, but show the

	// parameter value and result. (If aDefault is bad, Input is done

	// twice to it, both fail and address will be unspecified.)

	if (value != KErrNone)

		(void)addr.Input(aDefault);

	if (addr.Family() != KAfInet6)

		addr.ConvertToV4Mapped();

	aAddr = addr.Ip6Address();

	LOG(_LIT(KFormatAddr, "\t[%S] %S = %S [err=%d]"));

	LOG(Log::Printf(KFormatAddr, &aSection, &aName, &str, value));

	}

void CDndEngine::ConstructL()

	/**

	* Construct the engine.

	*

	* Open file and socket server sessions, read configuration parameters

	* from [resolver] and [lmnr] sections, create the timeout

	* manager (MTimeoutManager) and listener (CDndListener) instances.

	*/

	{

	LOG(Log::Printf(_L("--- DND starting, version: [%S] ---"), &KInet6Version));

	//

	// Start Socket Reader activity

	//

	CheckResultL(_L("Active Scheduler"), CActiveScheduler::Current() == NULL);

	CheckResultL(_L("Connect to File server"), iFS.Connect());

	CheckResultL(_L("Connect to Socket server"), iSS.Connect());

	CheckResultL(_L("Opening socket for Get/SetOpt"), iSocket.Open(iSS,  KAfInet, KSockDatagram, KProtocolInetUdp));

	// The utility socket should be pretty much "invisible", so disable some things...

	(void)iSocket.SetOpt(KSoUserSocket, KSolInetIp, 0);

	(void)iSocket.SetOpt(KSoKeepInterfaceUp, KSolInetIp, 0);

	// Failing to open hosts file is not a fatal error.

	(void)CheckResult(_L("Opening hosts file"), iHostsFile.Open());

	//

	// Setup Configuration Parameters

	//

	iParams.iRetries = GetIniValue(DND_INI_RESOLVER, DND_INI_RETRIES, KDndIni_Retries, 1, 255);

	iParams.iMinTime = GetIniValue(DND_INI_RESOLVER, DND_INI_MINTIME, KDndIni_MinTime, 1, KMaxTInt);

	iParams.iMaxTime = GetIniValue(DND_INI_RESOLVER, DND_INI_MAXTIME, KDndIni_MaxTime, 1, KMaxTInt);

	iParams.iSetupTime = GetIniValue(DND_INI_RESOLVER, DND_INI_SETUPTIME, KDndIni_SetupTime, 1, KMaxTInt);

	iParams.iSetupPoll = GetIniValue(DND_INI_RESOLVER, DND_INI_SETUPPOLL, KDndIni_SetupPoll, 1, KMaxTInt);

	iParams.iSprayMode = GetIniValue(DND_INI_RESOLVER, DND_INI_SPRAYMODE);

	iParams.iSkipNotFound = GetIniValue(DND_INI_RESOLVER, DND_INI_SKIPNOTFOUND);

	iParams.iQueryHack = GetIniValue(DND_INI_RESOLVER, DND_INI_QUERYHACK);

	iParams.iFlushOnConfig = GetIniValue(DND_INI_RESOLVER, DND_INI_FLUSHONCONFIG);

	iParams.iQueryOrder = GetIniValue(DND_INI_RESOLVER, DND_INI_QUERYORDER, KDndIni_QueryOrder, 0, 5);

#ifdef _LOG

		{

		if (iParams.iQueryOrder & KQueryOrder_OneQuery)

			{

			_LIT(a, "A");

			_LIT(aaaa, "AAAA");

			Log::Printf(_L("\t\t= (only %S)"),

				(iParams.iQueryOrder & KQueryOrder_PreferA) ? &a : &aaaa);

			}

		else

			{

			_LIT(sequentially, "sequentially");

			_LIT(parallel, "in parallel");

			_LIT(aaaa_a, "AAAA, A");

			_LIT(a_aaaa, "A, AAAA");

			Log::Printf(_L("\t\t= (%S %S)"),

				(iParams.iQueryOrder & KQueryOrder_PreferA) ? &a_aaaa : &aaaa_a,

				(iParams.iQueryOrder & KQueryOrder_Parallel) ? &parallel : &sequentially);

			}

		}

#endif

	iParams.iEDNS0 = GetIniValue(DND_INI_RESOLVER, DND_INI_EDNS0, KDndIni_EDNS0, KDnsMinHeader, 65000);

#ifdef LLMNR_ENABLED

	iParams.iLlmnrLlOnly = GetIniValue(DND_INI_LLMNR, LLMNR_INI_LLONLY, KLlmnrIni_LlOnly);

	iParams.iLlmnrPort = GetIniValue(DND_INI_LLMNR, LLMNR_INI_PORT, KLlmnrIni_Port, 0, 65535);

	iParams.iLlmnrRetries = GetIniValue(DND_INI_LLMNR, LLMNR_INI_RETRIES, KLlmnrIni_Retries, 1, 255);

	iParams.iLlmnrMinTime = GetIniValue(DND_INI_LLMNR, LLMNR_INI_MINTIME, KLlmnrIni_MinTime, 0, KMaxTInt);

	iParams.iLlmnrMaxTime = GetIniValue(DND_INI_LLMNR, LLMNR_INI_MAXTIME, KLlmnrIni_MaxTime, 1, KMaxTInt);

	iParams.iLlmnrHoplimit = GetIniValue(DND_INI_LLMNR, LLMNR_INI_HOPLIMIT, KLlmnrIni_Hoplimit, -1, 255);

	// Note: both addresses are stored as IPv6 (TIp6Addr)

	GetIniAddress(DND_INI_LLMNR, LLMNR_INI_IPV4ADDR, KLlmnrIni_Ipv4Addr, iParams.iLlmnrIpv4);

	GetIniAddress(DND_INI_LLMNR, LLMNR_INI_IPV6ADDR, KLlmnrIni_Ipv6Addr, iParams.iLlmnrIpv6);

#endif

	// Setup the timeout manager

	iTimer = TimeoutFactory::NewL();

	// Setup the "real" DNS resolver main

	iListener = MDndListener::NewL(*this);

	UnloadConfigurationFile();

	}

void CDndEngine::HandleCommandL(TInt aCommand)

	{

	switch(aCommand)

		{

		case EDndDump:

			if (iListener)

				iListener->HandleCommandL(aCommand);

			else

				iMain.Write(_L("Listener not active.\n"));

			break;

		default:

			// No own commands, pass the buck to other modules

			if (iListener)

				iListener->HandleCommandL(aCommand);

		}

	}

// CDndEngine::CheckResult

// ***********************

TInt CDndEngine::CheckResult(const TDesC &aText, TInt aResult)

	/**

	* If the result parameter is not KErrNone, output the

	* error message (with error number).

	*

	* @param aText	message to be output in case of error

	* @param aResult to be tested

	* @return aResult

	*/

	{

	_LIT(KFormat, "%S Error=%d");

	if (aResult != KErrNone)

		ShowTextf(KFormat, &aText, aResult);

	return aResult;

	}

// CDndEngine::CheckResultL

// ************************

void CDndEngine::CheckResultL(const TDesC &aText, TInt aResult)

	/**

	* Output success or fail message, and Leave if the code is not

	* KErrNone.

	*

	* @param aText	message to be output in case of error

	* @param aResult to be tested

	*/

	{

	if (CheckResult(aText, aResult) != KErrNone)

		User::Leave(aResult);

	}

// CDndEngine::ShowText

// ********************

void CDndEngine::ShowText(const TDesC &aText)

	/**

	* Write a text message.

	*

	* @param aText	is the message

	*/

	{

	iMain.Write(aText);

	}

// CDndEngine::ShowTextf

// *********************

void CDndEngine::ShowTextf(TRefByValue<const TDesC> aFmt, ...)

	/**

	* Write a message using format string.

	*

	* @param aFmt	is the format string

	*/

	{

	//coverity[var_decl];

	VA_LIST list;

	VA_START(list,aFmt);

	//coverity[uninit_use_in_call];

	iMain.WriteList(aFmt, list);

	}

// CDndEngine::LoadConfigurationFile

// *********************************

TBool CDndEngine::LoadConfigurationFile()

	/**

	* Load the configuration file.

	* Load the DND configuration file (INI file) into memory (iConfig),

	* if not already loaded. Only try loading once, if attempt

	* fails.

	* The CDndEngine::FindVar functions call this implicitly. There is

	* no need to call this explicitly.

	*

	* @return

	* @li	TRUE, if configuration availabe (iConfig != NULL)

	* @li	FALSE, if configuration file is not available

	*/

	{

	if (iConfig)

		return TRUE;	// Already loaded!

	// if iConfigErr != 0 (KErrNone), then an attempt for

	// loading configuration has been made and failed,

	// assume it never will succeed and avoid further

	// attemps on each FindVar...

	if (iConfigErr)

		return FALSE;

	LOG(Log::Printf(_L("CDndEngine::LoadConfigurationFile(): %S"), &DND_INI_DATA));

	TRAP(iConfigErr, iConfig = CESockIniData::NewL(DND_INI_DATA));

	return (iConfig != NULL);

	}

// CDndEngine::UnloadConfigurationFile

// ***********************************

void CDndEngine::UnloadConfigurationFile()

	/**

	* Free the configuration data.

	* The configuration information (INI file in iConfig) can be unloaded, if it is

	* assumed that no further need for configuration is required.

	*/

	{

	delete iConfig;

	iConfig = NULL;

	iConfigErr = 0;

	}

//

// Access to the configuration file

TBool CDndEngine::FindVar(const TDesC &aSection, const TDesC &aVarName, TPtrC &aResult)

	/**

	* @param aSection	the section name in the configution

	* @param aVarName	the variable name within section

	* @retval aResult	variable value, if found

	* @return

	* @li TRUE, if variable found

	* @li FALSE, if not found

	*/

	{

	if (LoadConfigurationFile())

		{

		ASSERT(iConfig);	// <-- lint gag

		return iConfig->FindVar(aSection, aVarName, aResult);

		}

	return FALSE;

	}

TBool CDndEngine::FindVar(const TDesC &aSection, const TDesC &aVarName, TInt &aResult)

	/**

	* @param aSection	the section name in the configution

	* @param aVarName	the variable name within section

	* @retval aResult	variable value, if found

	* @return

	* @li TRUE, if variable found

	* @li FALSE, if not found

	*/

	{

	if (LoadConfigurationFile())

		{

		ASSERT(iConfig);	// <-- lint gag

		return iConfig->FindVar(aSection, aVarName, aResult);

		}

	return FALSE;

	}