margintestertotalfreespace.h

来自「C++封装的视频采集代码」· C头文件 代码 · 共 141 行

#ifndef MarginTesterTotalFreeSpace_H
#define MarginTesterTotalFreeSpace_H

#include "CircularBufferSpaceInfo.h"

namespace oxsemi
{
    namespace circular_buffer
    {

        /**
         * @class MarginTesterTotalFreeSpace
         * is a simple policy class that determinds how the Thresholds of space in
         * a buffer class are tested against a Threshold value.
         * This implemntation will test the total remaining space in the buffer
         * against the Threshold, and is best suited to use where data is written, or
         * read accross the wrap-around boundry of the circular buffer.
         */        
        class MarginTesterTotalFreeSpace
        {
        
        public:
        
            /**     
             * @ctor.
             * @param iThreshold is an unsigned long the describes the new Threshold
             * to be used by the object.
             */
            MarginTesterTotalFreeSpace( unsigned long iThreshold = 0 )
                :
                miThreshold_( iThreshold )
            {};
            
            
            /**     
             * IsAboveThreshold tests the space info data against the Threshold held
             * by this object. The policy reports if the Threshold was violated.
             * @param spaceInfo is a reference to a CircularBufferSpaceInfo that#
             * holds information about the state of the circular buffer.
             * @return a boolean that is true if the implementation decides that
             * the buffer Threshold has been exceeded.
             */
            bool IsAboveThreshold( const CircularBufferSpaceInfo&  spaceInfo ) const;

            
            /**     
             * SetBufferDetails setter function.
             * @param iStartAddress is an unsigned long the describes the circular
             * buffer base address.
             * @param iLength is an unsigned long the describes the buffer length
             */
            void  SetBufferDetails( unsigned long iStartAddress,  unsigned long iLength ) {};

            
            /**     
             * SetThreshold setter function.
             * @param iThreshold is an unsigned long the describes the new Threshold
             * to be used by the object.
             */
            void  SetThreshold( unsigned long iThreshold );

            
            /**     
             * SetThreshold getter function.
             * @return an unsigned long that describes the Threshold used by the 
             * object.
             */
            unsigned long  GetThreshold() const;
            
        private:
        
            // storage for the Threshold value that is tested against
            unsigned long  miThreshold_; 
            
            
        }; // end class MarginTesterTotalFreeSpace

        // =====================================================================
        // =====================================================================
        // =====================================================================
        // =====================================================================

        /**     
         * IsAboveThreshold tests the space info data against the Threshold held
         * by this object. The policy reports if the Threshold was violated.
         * @param spaceInfo is a reference to a CircularBufferSpaceInfo that#
         * holds information about the state of the circular buffer.
         * @return a boolean that is true if the implementation decides that
         * the buffer Threshold has been exceeded.
         */
        inline bool MarginTesterTotalFreeSpace::IsAboveThreshold( const CircularBufferSpaceInfo&  spaceInfo ) const
        // {{{
        {
            // this implementation tests the total space left in the circular buffer 
            // against the Threshold.
            bool bAboveThreshold = 
                ( spaceInfo.GetFirstAvailableSection().GetLength() +
                  spaceInfo.GetSecondAvailableSection().GetLength()  ) >= miThreshold_;
//TRACE("$[%lu+%lu]:: %s (%lu)$n\n", spaceInfo.GetFirstAvailableSection().GetLength(), spaceInfo.GetSecondAvailableSection().GetLength(), bAboveThreshold ? "above" : "below", miThreshold_);

            return bAboveThreshold;
            
        }
        // }}}

        
        /**     
         * SetThreshold getter function.
         * @return an unsigned long that describes the Threshold used by the 
         * object.
         */
        inline unsigned long  MarginTesterTotalFreeSpace::GetThreshold() const
        // {{{
        {
            return miThreshold_;
        }
        // }}}
        

        /**     
         * SetThreshold setter function.
         * @param iThreshold is an unsigned long the describes the new Threshold
         * to be used by the object.
         */
        inline void  MarginTesterTotalFreeSpace::SetThreshold( unsigned long iThreshold )
        // {{{
        {
            miThreshold_ = iThreshold;
        }
        // }}}

        
        
    } // end namespace circular_buffer

} // end namespace oxsemi


#endif // __MarginTesterTotalFreeSpace_H__