c++ - 我如何 "reset"一个缓冲区？

Question

假设我创建了一个成员变量指针pBuffer。我将此缓冲区发送到某个未知区域以填充数据。现在假设 pBuffer 中有任意数量的数据。

问:有没有办法在不完全删除 pBuffer 的情况下重置它，同时仍然释放它占用的所有不必要的内存？

例子:

class Blah
{
public:

    unsigned char* pBuffer;

    Blah(){pBuffer = NULL;}
    ~Blah(){}

    FillBuffer()
    {
        //fill the buffer with data, doesn't matter how
    }

    ResetBuffer()
    {
        //????? reset the buffer without deleting it, still deallocate memory ?????
    }

};

int main()
{
    Blah b;
    b.FillBuffer();
    b.ResetBuffer();
    b.FillBuffer(); //if pBuffer were deleted, this wouldn't work
}

Answer 1

如果您知道缓冲区中的内容量与缓冲区中的剩余空间，请尝试 realloc()。