C/C++函数调用栈的实现方法

#pragma once

const int BUFFERSIZE = 1024;

const int growfactor = 2;

 

// this stack is used as call stack.

class TStack{

private:

size_t size;   // the stack length

size_t pos;    // the stack top position    

char *buffer;  // the buffer

private: void push(void* D, size_t bytecount);  // the implementation of push void* pop(size_t bytecount);   // the implementation of pop public: TStack(size_t _size = BUFFERSIZE, size_t _pos = 0);  // initialize TStack(const TStack& o);  // copy TStack& operator=(const TStack& o);  // assignment void pushInt(int i) { push(&i, sizeof(int)); }  // push an int void pushLong(long l) { push(&l, sizeof(long)); }  // push a long void pushfloat(double f) { push(&f, sizeof(f));}  // push  a double void pushPointer(void* p){ push(p, sizeof(p)); } // int int popInt() { return *(int *)pop(sizeof(int));}  // pop an int long popLong() { return *(long *)pop(sizeof(long)); }  // pop an int    double* popfloat() { return (double*)pop(sizeof(double)); }  // pop a double void* popPointer() { return pop(sizeof(void*)) ; } void clear() { pos = 0; }  };

#include "stdafx.h"

#include "TStack.h"

#include "new.h"

 

void TStack::push( void* D, size_t bytecount )

{

// if memory is not enough

// if run under multithread envionment,

// a lock or critical section should be added

if (pos + bytecount > size)

{    

  size_t oldsize = size;

       size *= growfactor;   

  char *newbuffer = new char[size];

  memcpy(newbuffer, buffer, oldsize);

  delete buffer;

  buffer = newbuffer;    

}

memcpy(buffer+pos, D, bytecount);

pos += bytecount;

}

 

void* TStack::pop( size_t bytecount )

{

// need synchronization for multithread environment

pos -= bytecount;

return &buffer[pos];

}

 

TStack::TStack( size_t _size , size_t _pos )

:size(_size),

pos(_pos),

buffer(new char[size])

{

}

 

TStack::TStack( const TStack &O )

:size(O.size),

pos(O.pos)

{

   buffer = new char[size];

   if (buffer != NULL)

   {

  memcpy(buffer, O.buffer, size);

   }

}

 

TStack& TStack::operator=( const TStack& O )

{

if (this == &O)

 return *this;      

    this->size = O.size;

this->pos = O.pos;

 

if (buffer != NULL)

{

delete buffer;

}

    buffer = new char[this->size]; 

if (buffer != NULL)

{

      memcpy(buffer, O.buffer, this->size);

}

return *this;

}