framework/inc/threadhelp/resetableguard.hxx

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  30
  31 #ifndef __FRAMEWORK_THREADHELP_RESETABLEGUARD_HXX_
  32 #define __FRAMEWORK_THREADHELP_RESETABLEGUARD_HXX_
  33
  34 //_________________________________________________________________________________________________________________
  35 //      my own includes
  36 //_________________________________________________________________________________________________________________
  37
  38 #include <threadhelp/inoncopyable.h>
  39 #include <threadhelp/imutex.h>
  40
  41 //#ifndef __FRAMEWORK_THREADHELP_THREADHELPBASE_HXX_
  42 //#include <threadhelp/threadhelpbase.hxx>
  43 //#endif
  44
  45 //_________________________________________________________________________________________________________________
  46 //      interface includes
  47 //_________________________________________________________________________________________________________________
  48
  49 //_________________________________________________________________________________________________________________
  50 //      other includes
  51 //_________________________________________________________________________________________________________________
  52 #include <sal/types.h>
  53
  54 //_________________________________________________________________________________________________________________
  55 //      namespace
  56 //_________________________________________________________________________________________________________________
  57
  58 namespace framework{
  59
  60 //_________________________________________________________________________________________________________________
  61 //      const
  62 //_________________________________________________________________________________________________________________
  63
  64 //_________________________________________________________________________________________________________________
  65 //      declarations
  66 //_________________________________________________________________________________________________________________
  67
  68 /*-************************************************************************************************************//**
  69     @short          implement a guard for implementing save thread access
  70     @descr                      These guard has an additional feature to well known one ::osl::Guard.
  71                     You can lock() and unlock() it very often!
  72                     A set bool flag inside protect this implementation against multiple lock() calls
  73                     without any unlock()! So the increasing of guarded mutex couldn't be greater then 1 ...
  74
  75     @attention      a) To prevent us against wrong using, the default ctor, copy ctor and the =operator are maked private!
  76                     b) Use interface "IMutex" of set LockHelper only - because we must support an exclusiv locking.
  77                        Interface "IRWLock" should be used by special guard implementations ... like "ReadGuard" or "WriteGuard"!
  78
  79     @implements         -
  80     @base           INonCopyable
  81
  82     @devstatus          ready to use
  83 *//*-*************************************************************************************************************/
  84 class ResetableGuard : private INonCopyable
  85 {
  86     //-------------------------------------------------------------------------------------------------------------
  87     //  public methods
  88     //-------------------------------------------------------------------------------------------------------------
  89     public:
  90
  91         /*-****************************************************************************************************//**
  92             @short              ctors
  93             @descr              Use these ctor methods to initialize the guard right.
  94                         Given lock reference must be valid - otherwise crashes could occure!
  95
  96             @seealso    -
  97
  98             @param      "pLock", pointer to lock helper of user
  99             @param      "rLock", reference to lock helper of user
 100             @return             -
 101
 102             @onerror    -
 103         *//*-*****************************************************************************************************/
 104         inline ResetableGuard( IMutex* pLock )
 105             :   m_pLock    ( pLock     )
 106             ,   m_bLocked  ( sal_False )
 107         {
 108             lock();
 109         }
 110
 111         //*********************************************************************************************************
 112         inline ResetableGuard( IMutex& rLock )
 113             :   m_pLock    ( &rLock    )
 114             ,   m_bLocked  ( sal_False )
 115         {
 116             lock();
 117         }
 118
 119         /*-****************************************************************************************************//**
 120             @short              dtor
 121             @descr              We must release set mutex if programmer forget it ...
 122
 123             @seealso    -
 124
 125             @param              -
 126             @return             -
 127
 128             @onerror    -
 129         *//*-*****************************************************************************************************/
 130         inline ~ResetableGuard()
 131         {
 132             unlock();
 133         }
 134
 135         /*-****************************************************************************************************//**
 136             @short              enable/disable the lock
 137             @descr              Use this methods to lock or unlock the mutex.
 138                         You can do it so often you wish to do that ...
 139
 140             @attention  We use another member to prevent us against multiple acquire calls of the same guard
 141                         without suitable release calls!
 142                         You don't must protect access at these bool member by using an own mutex ....
 143                         because nobody use the same guard instance from different threads!
 144                         It will be a function-local object every time.
 145
 146             @seealso    -
 147
 148             @param              -
 149             @return             -
 150
 151             @onerror    -
 152         *//*-*****************************************************************************************************/
 153         inline void lock()
 154         {
 155             if( m_bLocked == sal_False )
 156             {
 157                 m_pLock->acquire();
 158                 m_bLocked = sal_True;
 159             }
 160         }
 161
 162         //*********************************************************************************************************
 163         inline void unlock()
 164         {
 165             if( m_bLocked == sal_True )
 166             {
 167                 m_pLock->release();
 168                 m_bLocked = sal_False;
 169             }
 170         }
 171
 172     //-------------------------------------------------------------------------------------------------------------
 173     //  private methods
 174     //-------------------------------------------------------------------------------------------------------------
 175     private:
 176
 177         /*-****************************************************************************************************//**
 178             @short              disable using of these functions!
 179             @descr              It's not allowed to use this methods. Different problem can occure otherwise.
 180                         Thats why we disable it by make it private.
 181
 182             @seealso    other ctor
 183
 184             @param              -
 185             @return             -
 186
 187             @onerror    -
 188         *//*-*****************************************************************************************************/
 189         ResetableGuard();
 190
 191     //-------------------------------------------------------------------------------------------------------------
 192     //  private member
 193     //-------------------------------------------------------------------------------------------------------------
 194     private:
 195
 196         IMutex*         m_pLock     ;   /// pointer to safed lock member of user
 197         sal_Bool                m_bLocked       ;       /// protection against multiple lock() calls without unlock()
 198
 199 };              //      class ResetableGuard
 200
 201 }               //      namespace framework
 202
 203 #endif  //      #ifndef __FRAMEWORK_THREADHELP_RESETABLEGUARD_HXX_