memcpy实现

版权声明：本文为博主原创文章，未经博主允许不得转载。 https://blog.youkuaiyun.com/x30465947/article/details/80493069

   
   

     
     

      
      

     
     
     
     

      
      

       
       void *memcpy(void *dest, const void *src, int count)
      
      
     
     

     
     

      
      

     
     
     
     

      
      

       
       {
      
      
     
     

     
     

      
      

     
     
     
     

      
      
	
       
       void *ptr = dest;
      
      
     
     

     
     

      
      

     
     
     
     

      
      
 
      
      
     
     

     
     

      
      

     
     
     
     

      
      
	
       
       if (
       
       NULL == dest || 
       
       NULL == src || count <= 
       
       0)
      
      
     
     

     
     

      
      

     
     
     
     

      
      

       
       	{
      
      
     
     

     
     

      
      

     
     
     
     

      
      
		
       
       return 
       
       NULL;
      
      
     
     

     
     

      
      

     
     
     
     

      
      

       
       	}
      
      
     
     

     
     

      
      

     
     
     
     

      
      
 
      
      
     
     

     
     

      
      

     
     
     
     

      
      
	
       
       while (count--)
      
      
     
     

     
     

      
      

     
     
     
     

      
      
 
      
      
     
     

     
     

      
      

     
     
     
     

      
      

       
       	*(
       
       char *)dest++ = *(
       
       char *)src++;
      
      
     
     

     
     

      
      

     
     
     
     

      
      
 
      
      
     
     

     
     

      
      

     
     
     
     

      
      
	
       
       return ptr;
      
      
     
     

     
     

      
      

     
     
     
     

      
      

       
       }