// Copyright (c) 2005-2009 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:

// Name        : setpriority.cpp

// Part of     : LIBC

// Contains the source for fchdir

// Version     : 1.0

//

#include <sys/time.h>

#include <sys/resource.h>

#include <errno.h>

#include <e32std.h>

#include <e32const.h>

#if (defined(__SYMBIAN32__) && (defined(__WINSCW__) || defined(__WINS__)))

#include "libc_wsd_defs.h"

#endif

#ifdef EMULATOR

int *GET_WSD_VAR_NAME(ProcPriority, g)();

#define ProcPriority (*GET_WSD_VAR_NAME(ProcPriority, g)())

#else

extern int ProcPriority;

#endif //EMULATOR

/*

This function checks where in the priority range the parameter falls

and sets the priority accordingly.

It returns -1 if the paramter is out of range.

*/

TProcessPriority convPri( int pri)

	{

	TProcessPriority priority = TProcessPriority(-1);

	if((pri >= UPPER_LIMIT_PRIORITY_LOWEST) &&

		 ( pri <= LOWER_LIMIT_PRIORITY_LOWEST))

		{

		priority = EPriorityLow;

		}

	else if	((pri >= UPPER_LIMIT_PRIORITY_BELOW_NORMAL) &&

			   ( pri <= LOWER_LIMIT_PRIORITY_BELOW_NORMAL))

		{

		priority = EPriorityBackground;

		}

	else if((pri >= UPPER_LIMIT_PRIORITY_NORMAL) && 

	  		  ( pri <= LOWER_LIMIT_PRIORITY_NORMAL))

		{

		priority = EPriorityForeground;

		}

	else if((pri >= UPPER_LIMIT_PRIORITY_ABOVE_NORMAL) &&

			  ( pri <= LOWER_LIMIT_PRIORITY_ABOVE_NORMAL))

		{

		priority = EPriorityHigh;

		}

	/* If priority is anything other than this,

	   Symbian wont change it for user process/thread*/

	return priority;

	}	

/*

This function setpriority() checks if the which and who parameters

sent are 'the process priority' and 'the current process' respectively,

i.e. PROC_PROCESS and 0 respectively. And calls the function convPri()

to check in which range the priority falls and returns likewise.

It returns a value in the range 0 on success and -1 on failure.

The function setpriority() shall ignore the values PRIO_PGRP,

PRIO_USER as the argument 'which' and any other value other than

0 for 'who' shall not be considered. For effective change in priority,

the  'value' should be in the range of -15 to 19. If the 'value' is 

greater than the greatest or less than the least, it will set the 'value'

to the maximum or minimum value respectively.

*/	

extern "C" {

EXPORT_C int setpriority( int which, int who, int value )

	{

	int retval = -1;

	if((who == 0) && (which == PRIO_PROCESS ))

		{

		if(value > LOWER_LIMIT_PRIORITY_LOWEST)

			{

			value = LOWER_LIMIT_PRIORITY_LOWEST;

			}

		if(value < UPPER_LIMIT_PRIORITY_HIGHEST)

			{

			value = UPPER_LIMIT_PRIORITY_ABOVE_NORMAL;

			}

		int priority = convPri( value );

		if( priority != -1 )

			{

			RProcess pro;

			pro.SetPriority( convPri( value ) );

			ProcPriority = value;

			retval = 0;

			}

		}

	//handling error case and not supported case

	if( retval == -1 )

		{

		errno = ENOSYS;

		}

	return retval;

	}

} //extern "C"