1 /*

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

     3  * All rights reserved.

     4  * This component and the accompanying materials are made available

     5  * under the terms of "Eclipse Public License v1.0"

     6  * which accompanies this distribution, and is available

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

     8  *

     9  * Initial Contributors:

    10  * Nokia Corporation - initial contribution.

    11  *

    12  * Contributors:

    13  *

    14  * Description:

    15  *

    16  */

    17 #include "cxestatemachinebase.h"

    18 #include "cxutils.h"

    19 #include "cxeerrormappingsymbian.h"

    20 #include "cxestate.h"

    21 

    22 CxeStateMachineBase::CxeStateMachineBase( const char* stateMachineName ) :

    23     mStateId(0), mName(stateMachineName)

    24 {

    25 }

    26 

    27 CxeStateMachineBase::~CxeStateMachineBase()

    28 {

    29     qDeleteAll(mStates);

    30     mStates.clear();

    31 }

    32 

    33 bool CxeStateMachineBase::addState( CxeState* state )

    34 {

    35     bool success = true;

    36 

    37     if (!state) {

    38         // given parameter is null pointer

    39         success = false;

    40     } else {

    41         // Make sure any of the existing stateId don't have overlapping bits.

    42         // We need to be able to use bitwise AND operator for stateIds.

    43         QList<int> stateIds = mStates.keys();

    44         foreach(int i, stateIds) {

    45             if ((i & state->stateId()) != 0) {

    46                 success = false;

    47                 break;

    48             }

    49         }

    50     }

    51 

    52     // if no errors

    53     if (success) {

    54         mStates[state->stateId()] = state; // state is now owned by the state machine

    55     }

    56 

    57     return success;

    58 }

    59 

    60 bool CxeStateMachineBase::setState( int stateId, int error )

    61 {

    62     bool success = true;

    63 

    64     if (stateId == mStateId) {

    65         // No transition, nothing needs to be done

    66         return success;

    67     }

    68 

    69     if (mStates.contains(stateId)) {

    70         // New state name known, print it

    71         CX_DEBUG(("%s::setState(%s, %d)", mName.toAscii().constData(),

    72                 mStates[stateId]->name().toAscii().constData(), error));

    73     } else {

    74         // Unknown state...

    75         CX_DEBUG(("%s::setState(UNKNOWN[%d], %d)", mName.toAscii().constData(),

    76                 stateId, error));

    77     }

    78 

    79     // State state machine does not use the error parameter itself.

    80     // It is only forwarded to handleStateChanged to be passed

    81     // on as a parameter in the stateChanged() signal.

    82 

    83     // setStateId itself will never return an error.

    84     // If an illegal state or state change is detected, it will panic the application (because it is a design error).

    85 

    86     success = verifyStateChange(stateId);

    87 

    88     if (success) {

    89         mStateId = stateId;

    90         handleStateChanged(mStateId, CxeErrorHandlingSymbian::map(error));

    91     }

    92 

    93     return success;

    94 }

    95 

    96 bool CxeStateMachineBase::setInitialState( int stateId )

    97 {

    98     bool success = mStates.contains(stateId);

    99 

   100     if (success) {

   101         // New state name known, print it

   102         CX_DEBUG(("%s::setInitialState(%s)", mName.toAscii().constData(),

   103                 mStates[stateId]->name().toAscii().constData()));

   104     } else {

   105         // Unknown state...

   106         CX_DEBUG(("%s::setInitialState(UNKNOWN[%d])", mName.toAscii().constData(),

   107                 stateId));

   108     }

   109 

   110     // check that state changes have not been made

   111     // and this is the one and only setInitialState call

   112     success = (success && mStateId == 0);

   113 

   114     if (success) {

   115         mStateId = stateId;

   116     } else {

   117         CX_DEBUG(("%s state has already been set", mName.toAscii().constData()));

   118     }

   119     return success;

   120 }

   121 

   122 int CxeStateMachineBase::stateId() const

   123 {

   124     return mStateId;

   125 }

   126 

   127 bool CxeStateMachineBase::verifyStateChange( int newStateId )

   128 {

   129     bool allowStateChange = false;

   130 

   131     // Check that current state can be found in the state chart

   132     if ( mStates.contains(stateId()) ) {

   133         // Check that current state allows change to the new state

   134         CxeState *currentState = mStates[stateId()];

   135         allowStateChange = (currentState->allowedNextStates() & newStateId);

   136     }

   137 

   138     return allowStateChange;

   139 }

   140 

   141 

   142 

   143