// file: cb.cc//// this file contains an implementation of the circular buffer class.// for convenience, we have grouped all methods into a single file.//////-----------------------------------------------------------------------------// system include files//#include <stdlib.h>#include <memory.h>// isip include files//#include "cb.h"//-----------------------------------------------------------------------------//// class: Circular_buffer//// description: a circular buffer class implemented as a linear array//              with logic that checks for wrap-around of pointers////-----------------------------------------------------------------------------// constructors/destructors//-----------------------------------------------------------------------------Circular_buffer::Circular_buffer() {  idx_d = -1;  size_d = 0;  buf_d = (float*)NULL;}Circular_buffer::~Circular_buffer() {  idx_d = -1;  size_d = 0;  delete [] buf_d;}//-----------------------------------------------------------------------------// allocation//-----------------------------------------------------------------------------void Circular_buffer::allocate_cc(int num_elements) {  // check if a buffer already exists  //  if (buf_d != (float*)NULL)    {delete [] buf_d;}  // allocate a buffer  //  idx_d = 0;  size_d = num_elements;  buf_d = new float[size_d];  // clear memory  //  memset(buf_d, (int)0, size_d*sizeof(float));  // exit gracefully  //}//-----------------------------------------------------------------------------// indexing methods//-----------------------------------------------------------------------------int Circular_buffer::add_cc(float new_value) {  // increment the pointer  //  idx_d++;  if (idx_d >= size_d)    {idx_d -= size_d;}  else if (idx_d < (int)0)    {idx_d += size_d;}      // assign the value  //  buf_d[idx_d] = new_value;  // return the new pointer  //  return idx_d;}//-----------------------------------------------------------------------------// overloaded operators//-----------------------------------------------------------------------------float Circular_buffer::operator() (int index) {  // note that the index is actually an offset from idx_d  //  int idx = idx_d + index;  // check the index  //  if (idx > size_d)    {idx -= size_d;}  else if (idx < (int)0)    {idx += size_d;}  // return the corresponding value  //  return buf_d[idx];}