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#include "config.h"
#include <stdio.h>
#include <string.h>
/**
* container_of - routine for upcasting
*
* It is often convenient to create code where the caller registers a pointer
* to a generic structure and a callback. The callback might know that the
* pointer points to within a larger structure, and container_of gives a
* convenient and fairly type-safe way of returning to the enclosing structure.
*
* This idiom is an alternative to providing a void * pointer for every
* callback.
*
* Example:
* #include <stdio.h>
* #include <ccan/container_of/container_of.h>
*
* struct timer {
* void *members;
* };
*
* struct info {
* int my_stuff;
* struct timer timer;
* };
*
* static void my_timer_callback(struct timer *timer)
* {
* struct info *info = container_of(timer, struct info, timer);
* printf("my_stuff is %u\n", info->my_stuff);
* }
*
* static void register_timer(struct timer *timer)
* {
* (void)timer;
* (void)my_timer_callback;
* //...
* }
*
* int main(void)
* {
* struct info info = { .my_stuff = 1 };
*
* register_timer(&info.timer);
* // ...
* return 0;
* }
*
* License: CC0 (Public domain)
* Author: Rusty Russell <rusty@rustcorp.com.au>
*/
int main(int argc, char *argv[])
{
if (argc != 2)
return 1;
if (strcmp(argv[1], "depends") == 0) {
printf("ccan/check_type\n");
return 0;
}
return 1;
}
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