framework/inc/threadhelp/irwlock.h

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  19
  20 #ifndef __FRAMEWORK_THREADHELP_IRWLOCK_H_
  21 #define __FRAMEWORK_THREADHELP_IRWLOCK_H_
  22
  23 namespace framework{
  24
  25 /*-************************************************************************************************************//**
  26     @descr          A guard (specialy a write guard) support different internal working states.
  27                     His lock can set for reading or writing/reading! Or he was unlocked by user ...
  28 *//*-*************************************************************************************************************/
  29 enum ELockMode
  30 {
  31     E_NOLOCK    ,
  32     E_READLOCK  ,
  33     E_WRITELOCK
  34 };
  35
  36 /*-************************************************************************************************************//**
  37     @descr          We implement two guards for using an rw-lock. But if you wish to implement
  38                     different rw-locks to you will have problems by using with same guard implementation!
  39                     Thats why we define this "pure virtual base class" ...
  40                     All rw-locks must support this base interface for working and all guard must use this one too!
  41 *//*-*************************************************************************************************************/
  42 class IRWLock
  43 {
  44     //-------------------------------------------------------------------------------------------------------------
  45     //  public methods
  46     //-------------------------------------------------------------------------------------------------------------
  47     public:
  48
  49         /*-****************************************************************************************************//**
  50             @descr      These functions must be supported by a derived class!
  51                             acquireReadAccess()     -try to register thread as reader
  52                             releaseReadAccess()     -unregister thread as reader
  53                             acquireWriteAccess()    -try to register thread as writer
  54                             releaseWriteAccess()    -unregister thread as writer
  55                             downgradeWriteAccess()  -make writer to reader
  56         *//*-*****************************************************************************************************/
  57         virtual void acquireReadAccess    () =0;
  58         virtual void releaseReadAccess    () =0;
  59         virtual void acquireWriteAccess   () =0;
  60         virtual void releaseWriteAccess   () =0;
  61         virtual void downgradeWriteAccess () =0;
  62
  63     protected:
  64         ~IRWLock() {}
  65 };      //  class IRWLock
  66
  67 }       //  namespace framework
  68
  69 #endif  //  #ifndef __FRAMEWORK_THREADHELP_IRWLOCK_H_
  70
  71 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */