CPP/Common/MyBuffer.h

// Common/MyBuffer.h

#ifndef __COMMON_MY_BUFFER_H
#define __COMMON_MY_BUFFER_H

#include "Defs.h"

/* 7-Zip now uses CBuffer only as CByteBuffer.
   So there is no need to use MY_ARRAY_NEW macro in CBuffer code. */

template <class T> class CBuffer
{
  T *_items;
  size_t _size;

public:
  void Free()
  {
    if (_items)
    {
      delete []_items;
      _items = 0;
    }
    _size = 0;
  }
  
  CBuffer(): _items(0), _size(0) {};
  CBuffer(size_t size): _items(0), _size(0) { _items = new T[size]; _size = size; }
  CBuffer(const CBuffer &buffer): _items(0), _size(0)
  {
    size_t size = buffer._size;
    if (size != 0)
    {
      _items = new T[size];
      memcpy(_items, buffer._items, size * sizeof(T));
      _size = size;
    }
  }

  ~CBuffer() { delete []_items; }

  operator       T *()       { return _items; }
  operator const T *() const { return _items; }
  size_t Size() const { return _size; }

  void Alloc(size_t size)
  {
    if (size != _size)
    {
      Free();
      if (size != 0)
      {
        _items = new T[size];
        _size = size;
      }
    }
  }

  void AllocAtLeast(size_t size)
  {
    if (size > _size)
    {
      Free();
      _items = new T[size];
      _size = size;
    }
  }

  void CopyFrom(const T *data, size_t size)
  {
    Alloc(size);
    if (size != 0)
      memcpy(_items, data, size * sizeof(T));
  }

  void ChangeSize_KeepData(size_t newSize, size_t keepSize)
  {
    if (newSize == _size)
      return;
    T *newBuffer = NULL;
    if (newSize != 0)
    {
      newBuffer = new T[newSize];
      if (keepSize > _size)
        keepSize = _size;
      if (keepSize != 0)
        memcpy(newBuffer, _items, MyMin(keepSize, newSize) * sizeof(T));
    }
    delete []_items;
    _items = newBuffer;
    _size = newSize;
  }

  CBuffer& operator=(const CBuffer &buffer)
  {
    if (&buffer != this)
      CopyFrom(buffer, buffer._size);
    return *this;
  }
};

template <class T>
bool operator==(const CBuffer<T>& b1, const CBuffer<T>& b2)
{
  size_t size1 = b1.Size();
  if (size1 != b2.Size())
    return false;
  if (size1 == 0)
    return true;
  return memcmp(b1, b2, size1 * sizeof(T)) == 0;
}

template <class T>
bool operator!=(const CBuffer<T>& b1, const CBuffer<T>& b2)
{
  size_t size1 = b1.Size();
  if (size1 != b2.Size())
    return true;
  if (size1 == 0)
    return false;
  return memcmp(b1, b2, size1 * sizeof(T)) != 0;
}


// typedef CBuffer<char> CCharBuffer;
// typedef CBuffer<wchar_t> CWCharBuffer;
typedef CBuffer<unsigned char> CByteBuffer;


template <class T> class CObjArray
{
protected:
  T *_items;
private:
  // we disable copy
  CObjArray(const CObjArray &buffer);
  void operator=(const CObjArray &buffer);
public:
  void Free()
  {
    delete []_items;
    _items = 0;
  }
  CObjArray(size_t size): _items(0)
  {
    if (size != 0)
    {
      MY_ARRAY_NEW(_items, T, size)
      // _items = new T[size];
    }
  }
  CObjArray(): _items(0) {};
  ~CObjArray() { delete []_items; }
  
  operator       T *()       { return _items; }
  operator const T *() const { return _items; }
  
  void Alloc(size_t newSize)
  {
    delete []_items;
    _items = 0;
    MY_ARRAY_NEW(_items, T, newSize)
    // _items = new T[newSize];
  }
};

typedef CObjArray<unsigned char> CByteArr;
typedef CObjArray<bool> CBoolArr;
typedef CObjArray<int> CIntArr;
typedef CObjArray<unsigned> CUIntArr;


template <class T> class CObjArray2
{
  T *_items;
  unsigned _size;

  // we disable copy
  CObjArray2(const CObjArray2 &buffer);
  void operator=(const CObjArray2 &buffer);
public:
  
  void Free()
  {
    delete []_items;
    _items = 0;
    _size = 0;
  }
  CObjArray2(): _items(0), _size(0) {};
  /*
  CObjArray2(const CObjArray2 &buffer): _items(0), _size(0)
  {
    size_t newSize = buffer._size;
    if (newSize != 0)
    {
      T *newBuffer = new T[newSize];;
      _items = newBuffer;
      _size = newSize;
      const T *src = buffer;
      for (size_t i = 0; i < newSize; i++)
        newBuffer[i] = src[i];
    }
  }
  */
  /*
  CObjArray2(size_t size): _items(0), _size(0)
  {
    if (size != 0)
    {
      _items = new T[size];
      _size = size;
    }
  }
  */

  ~CObjArray2() { delete []_items; }
  
  operator       T *()       { return _items; }
  operator const T *() const { return _items; }
  
  unsigned Size() const { return (unsigned)_size; }
  bool IsEmpty() const { return _size == 0; }

  // SetSize doesn't keep old items. It allocates new array if size is not equal
  void SetSize(unsigned size)
  {
    if (size == _size)
      return;
    T *newBuffer = NULL;
    if (size != 0)
    {
      MY_ARRAY_NEW(newBuffer, T, size)
      // newBuffer = new T[size];
    }
    delete []_items;
    _items = newBuffer;
    _size = size;
  }

  /*
  CObjArray2& operator=(const CObjArray2 &buffer)
  {
    Free();
    size_t newSize = buffer._size;
    if (newSize != 0)
    {
      T *newBuffer = new T[newSize];;
      _items = newBuffer;
      _size = newSize;
      const T *src = buffer;
      for (size_t i = 0; i < newSize; i++)
        newBuffer[i] = src[i];
    }
    return *this;
  }
  */
};

#endif