commands/backup/backup.cpp
author Tom Sutcliffe <thomas.sutcliffe@accenture.com>
Thu, 26 Aug 2010 00:49:35 +0100
changeset 45 534b01198c2d
parent 0 7f656887cf89
permissions -rw-r--r--
Added ENotifyKeypresses and ECaptureCtrlC flags to CCommandBase. Commands can now get keypresses and handle ctrl-C via callbacks instead of having to implement custom active objects. As part of this extended the CCommandBase extension interface to MCommandExtensionsV2 for the new virtual functions KeyPressed(TUint aKeyCode, TUint aModifiers) and CtrlCPressed(). sudo now cleans up correctly by using ECaptureCtrlC.

// backup.cpp
// 
// Copyright (c) 2008 - 2010 Accenture. All rights reserved.
// This component and the accompanying materials are made available
// under the terms of the "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:
// Accenture - Initial contribution
//

#include "backup.h"

_LIT(KBackupOp,		"-b");

//
// CBackupDriver
//
CBackupDriver* CBackupDriver::NewL(MBackupParent& aParent)
	{
	CBackupDriver* self = new (ELeave) CBackupDriver(aParent);
	CleanupStack::PushL(self);
	self->ConstructL();
	CleanupStack::Pop(self);
	return self;
	}

CBackupDriver::CBackupDriver(MBackupParent& aParent):
CActive(CActive::EPriorityStandard), iParent(aParent)
	{
	CActiveScheduler::Add(this);
	}

CBackupDriver::~CBackupDriver()
	{
	Cancel();
	}

void CBackupDriver::ConstructL()
	{
	}

void CBackupDriver::SendInstructionL(MBackupObserver::TFileLockFlags aInstruction)
	{
	iInstruction = aInstruction;
	switch (iInstruction)
		{
		case MBackupObserver::EReleaseLockNoAccess:
			LaunchProcessL();
		break;

		case MBackupObserver::ETakeLock:
			TerminateProcessL();
		break;

		default:
			User::Leave(KErrNotSupported);
		break;		
		};
	}

//
// CBackupDriver::ChildProcessExists
// checks whether the backup_child process
// is already running
//
TBool CBackupDriver::ChildProcessExists()
	{
	_LIT(KWildCard, "*");
	TName woop(KBackupProcessName);
	woop.Append(KWildCard);
	TFindProcess check(woop);
	TFullName name;
	TInt result = check.Next(name);
	if (result == KErrNone)
		return ETrue;	
	return EFalse;
	}

//
// CBackupDriver::LaunchProcessL
// spawns the backup_child process
// & waits to rendezvous
//
void CBackupDriver::LaunchProcessL()
	{
	if (ChildProcessExists())
		User::Leave(KErrInUse);
	
	_LIT(KExeExt, ".exe");
	TName name(KBackupProcessName);
	name.Append(KExeExt);
	User::LeaveIfError(iChild.Create(name, KBackupOp, EOwnerProcess));
	iChild.Resume();
	iChild.Rendezvous(iStatus);
	SetActive();
	}

//
// CBackupDriver::TerminateProcessL
// open the backup_child process & signal it's semaphore
// that semaphore is the signal to shut itself down cleanly
//
void CBackupDriver::TerminateProcessL()
	{
	if (!ChildProcessExists())
		User::Leave(KErrNotFound);
	
	// signal the semaphore 
	RSemaphore sem;
	User::LeaveIfError(sem.OpenGlobal(KBackupSemaphore, EOwnerProcess));
	sem.Signal();

	SelfComplete(KErrNone);
	}

void CBackupDriver::SelfComplete(const TInt aError)
	{
	ASSERT(!IsActive());
	iStatus = KRequestPending;
	TRequestStatus* status = &iStatus;
	User::RequestComplete(status, aError);
	SetActive();
	}

//
// CBackupDriver::RunL
// 
void CBackupDriver::RunL()
	{
	iParent.Finished(iStatus.Int());
	}

//
// CBackupDriver::DoCancel
//
void CBackupDriver::DoCancel()
	{
	ASSERT(EFalse); // not dealing with this!
	}


//
// CCmdBackup
//
CCommandBase* CCmdBackup::NewLC()
	{
	CCmdBackup* self = new (ELeave) CCmdBackup();
	CleanupStack::PushL(self);
	self->BaseConstructL();
	return self;
	}

CCmdBackup::~CCmdBackup()
	{
	delete iBackup;
	}

CCmdBackup::CCmdBackup() : 
CCommandBase(CCommandBase::EManualComplete)
	{
	}

const TDesC& CCmdBackup::Name() const
	{
	_LIT(KName, "backup");	
	return KName;
	}

void CCmdBackup::DoRunL()
	{
	// spawn the stuff I need to do the task
	iBackup = CBackupDriver::NewL(*this);

	// process the argument
	MBackupObserver::TFileLockFlags flag = MBackupObserver::EReleaseLockNoAccess;
	switch (iOperation)
		{
	case EStart:
		flag = MBackupObserver::EReleaseLockNoAccess;
		break;
	case EStop:
		flag = MBackupObserver::ETakeLock;
		break;
	default:
		User::LeaveIfError(KErrArgument);
		}
			
	// send the instruction through
	iBackup->SendInstructionL(flag);
	}

void CCmdBackup::ArgumentsL(RCommandArgumentList& aArguments)
	{
	_LIT(KArgOperation, "operation");
	aArguments.AppendEnumL((TInt&)iOperation, KArgOperation);
	}

void CCmdBackup::Finished(const TInt aError)
	{
	Complete(aError);
	}

EXE_BOILER_PLATE(CCmdBackup)