examples/SysLibs/TaskSchedulerExample/taskexecutor.cpp

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/*
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  may be used to endorse or promote products derived from this software
  without specific prior written permission.

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Description:
This is simple code that executes the task scheduled by the task scheduler. 
The code also checks if the task requester has the required capability.
This window belongs to the task scheduled to execute by the main program. 
It shows the details of the task information passed by the Task Scheduler 
to the executed program.   
*/





#include <schtask.h>
#include <e32cons.h>

_LIT(KTaskConsoleName, "TaskExecutor");
_LIT(KContent,"\nContents of task file:\n");
_LIT(KTask,"\nRunning task: %S");
_LIT(KTaskData,"\nThis is the task data for a");
_LIT(KTaskId,"\nThe task Id is: %d\n");
_LIT(KValidity,"Task is valid until %S\n");
_LIT(KDateString,"%H%:1%T %*E%*D%X%*N%Y %1 %2 %3");
_LIT(KPressAnyKey,"Press any key to continue \n");
_LIT(KAbort,"\nCapabilities of the task scheduler and the executor do not match. Task aborted\n");
_LIT(KSidMismatch,"SID of the task executor is not same as that of the scheduler. Task aborted\n");
// Uid of the task requester
const TUint32 KTaskSchedulerSid = 0xE80000B5;
const TCapability KTaskCapability = ECapabilityWriteDeviceData;

void TaskExecuteL(RFile& aTaskFile)
        {
        // Construct console
        CConsoleBase* console = Console::NewL(KTaskConsoleName, TSize(KConsFullScreen, KConsFullScreen));
        CleanupStack::PushL(console);
        console->Printf(KContent);
        
        // Open the filestore
        CFileStore*     store = CDirectFileStore::FromLC(aTaskFile);//pushes store onto CleanupStack
        RStoreReadStream instream;
        
        // Open the file containing the store
        instream.OpenLC(*store,store->Root());//pushes instream onto CleanupStack

        // Get task count
        TInt count = instream.ReadInt32L();
        for (TInt i=0;i<count;i++)
                {
                CScheduledTask* task = CScheduledTask::NewLC(instream); //pushes task onto CleanupStack
                
                // Check if this is the SID of task requester
                if(task->SecurityInfo().iSecureId == KTaskSchedulerSid)
                        {
                        
                        // Check if the requester has the necessary capability to run 
                        // the scheduled tasks.
                        if(task->SecurityInfo().iCaps.HasCapability(KTaskCapability))
                                {
                                TBuf<50> buf;
                                buf.Format(KTask, &task->Info().iName);
                                console->Printf(buf);
                        
                                HBufC* data = const_cast<HBufC*>(&(task->Data()));
                
                                console->Printf(KTaskData);
                                console->Printf(*data);
                                
                                console->Printf(KTaskId,task->Info().iTaskId);
                
                                // Get the time when the task stops being valid
                                TTsTime tstime = task->ValidUntil();
                                const TTime time = tstime.GetLocalTime();
                                TBuf<30> dateString;
                                time.FormatL(dateString,(KDateString));
                                console->Printf(KValidity, &dateString);
                                }
                        else
                                {
                                console->Printf(KAbort);        
                                }
                        }
                else
                        {
                        console->Printf(KSidMismatch);
                        }
                console->Printf(KPressAnyKey);
                console->Getch();

                CleanupStack::PopAndDestroy(task);
                        
                }
        
        CleanupStack::PopAndDestroy(3); // instream, store, console
        }


TInt Execute()
        {
        TInt err = KErrNoMemory;
        CTrapCleanup* cleanup = CTrapCleanup::New();
        if (cleanup)
                {
                RFile file;
                
                // Needs to be called early-on to allow the task scheduler server
                // to adopt the already open task file from the task scheduler
                err = file.AdoptFromCreator(TScheduledTaskFile::FsHandleIndex(),
                                                                        TScheduledTaskFile::FileHandleIndex());
                if (err != KErrNone)
                        {
                        return err;             
                        }
                        
                // Execute 
                TRAPD(err,TaskExecuteL(file));
                if(err != KErrNone)
                        {
                        User::Panic(_L("Failed to complete"),err);
                        }
        
                // Close the file
                file.Close();           
                delete cleanup;
                }               
        return err;
        }


GLDEF_C TInt E32Main()
        {
        return Execute();
        }

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