libbu++ is finally laid out the way it should be, trunk, branches, and tags.

1 files changed, 112 insertions, 0 deletions

diff --git a/src/ringlist.h b/src/ringlist.h
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+#ifndef RINGLIST_H
+#define RINGLIST_H
+
+#include "list.h"
+
+/**
+ * A RingList or Ring Buffer implementation.  This is a list that never grows in
+ * size once it is created, but instead once it is full new items added to the
+ * RingList replace the oldest items and the zero-index is virtually shifted.
+ * Since no data is actually moved when zero-index moves, this is very
+ * efficient.
+ * <br>
+ * The items removed are not actually deleted by the RingList, so instead they
+ * are first moved into a temporary "Push Buffer" that can be accessed so that
+ * elements pushed off the edge of the RingList can be accessed for cleanup.
+ *@author Mike Buland
+ */
+class RingList : public List
+{
+public:
+        /**
+         * Construct a RingList with a fixed initial size.  This size never changes
+         * unless setSize is called later during normal operation.
+         *@param nInitSize The number of elements to allocate.
+         */
+        RingList( int nInitSize );
+
+        /**
+         * Clean up the data structures, but not the contained elements.
+         */
+        ~RingList();
+        
+        /**
+         * Get an element at the specified index.
+         *@param nIndex The index of the element to retreive.
+         *@returns A pointer to the requested element, or NULL if the element is
+         * not found or not initialized yet.
+         */
+        void *getAt( int nIndex );
+
+        /**
+         * Append an element to the end of the list, overwriting the begining if
+         * necesarry.
+         *@param pData The pointer to append to the RingList.
+         */
+        void append( void *pData );
+
+        /**
+         * Insert an element before another in the RingList, pushing all after it
+         * down the list.
+         *@param pData The data to insert.
+         *@param nPos The position that new the element should occupy in the list.
+         */
+        void insertBefore( void *pData, int nPos = 0 );
+
+        /**
+         * Get the size of the array.
+         */
+        int getSize();
+
+        /**
+         * Is the RingList empty?
+         *@returns True if it is empty, false otherwise.
+         */
+        bool isEmpty();
+
+        /**
+         * Delete an element in the list, moving all later elements down one index.
+         *@param nIndex The index of the element to delete.
+         */
+        void deleteAt( int nIndex );
+
+        /**
+         * Remove all elements from the RingList.
+         */
+        void empty();
+
+        /**
+         * Set a new size for the RingList.  Be careful with this one, if shrinking
+         * this may quietly create a memory leak.
+         *@param nNewSize The new size to set the RingList to.
+         *@todo Either fix this memory leak somehow or remove this function.
+         */
+        void setSize( int nNewSize );
+        
+        /**
+         * Set a specific element to a new value.
+         *@param nIndex The zero-based index to change the value of.
+         *@param pData The data to put at the location specified by nIndex.
+         */
+        void setAt( int nIndex, void *pData );
+
+        /**
+         * Retrieve the contents of the push buffer.  This is the data that is
+         * pushed off the end of the array if you append data and the list is full.
+         * This should be checked after every append operation to be sure there
+         * isn't anything that needs deleting.
+         *@returns The last value pushed off the RingList, or NULL if nothing was
+         * pushed off.
+         */
+        void *getPushBuf();
+        
+private:
+        int nFirstIndex;        /**< The index to be translated as zero. */
+        int nRealLength;        /**< The Amount of storage space available. */
+        int nDataLength;        /**< The number of elements filled in. */
+        void **apData;          /**< The actual data storage. */
+        void *pPushBuf;         /**< The push buffer. */
+
+};
+
+#endif