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/*
* File : lfq_test.c
* Author : Jérémy Zurcher <jeremy@asynk.ch>
* Date : 01/11/09
* License :
*
* Permission is hereby granted, free of charge, to any person obtaining
* a copy of this software and associated documentation files (the
* "Software"), to deal in the Software without restriction, including
* without limitation the rights to use, copy, modify, merge, publish,
* distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so, subject to
* the following conditions:
*
* The above copyright notice and this permission notice shall be
* included in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
* LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
* WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*
*/
#include "stdio.h"
#include "stdlib.h"
#include "stddef.h"
#define container_of(ptr, type, member) ({ \
const typeof( ((type *)0)->member ) *__mptr = (ptr); \
(type *)( (char *)__mptr - offsetof(type,member) );})
struct node {
int data1;
int data2;
int data3;
int data4;
int data5;
};
#define my_offset(ptr, type, member) ( { (type*)(((char*)ptr)-offsetof(type,member)); } )
struct node n;
struct node* use_container_of() {
return container_of( &n.data3, struct node, data3);
}
struct node* use_mine() {
return my_offset( &n.data3, struct node, data3);
/* return (struct node*)(((char*)&n.daat3)-OFFSET); */
}
struct node* use_struct(){
return &n;
}
int main(int argc, char *argv[]) {
printf ("%X\n", (int)use_container_of());
printf ("%X\n", (int)use_mine());
printf ("%X\n", (int)use_struct());
return EXIT_SUCCESS;
}
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