Include all the tools under ccan_tools dir, hacked to work for me.
[ccan] / container_of / container_of.h
1 #ifndef CCAN_CONTAINER_OF_H
2 #define CCAN_CONTAINER_OF_H
3 #include <stddef.h>
4
5 #include "config.h"
6 #include "check_type/check_type.h"
7
8 /**
9  * container_of - get pointer to enclosing structure
10  * @member_ptr: pointer to the structure member
11  * @containing_type: the type this member is within
12  * @member: the name of this member within the structure.
13  *
14  * Given a pointer to a member of a structure, this macro does pointer
15  * subtraction to return the pointer to the enclosing type.
16  *
17  * Example:
18  *      struct info
19  *      {
20  *              int some_other_field;
21  *              struct foo my_foo;
22  *      };
23  *
24  *      struct info *foo_to_info(struct foo *foop)
25  *      {
26  *              return container_of(foo, struct info, my_foo);
27  *      }
28  */
29 #define container_of(member_ptr, containing_type, member)               \
30          ((containing_type *)                                           \
31           ((char *)(member_ptr) - offsetof(containing_type, member))    \
32           - check_types_match(*(member_ptr), ((containing_type *)0)->member))
33
34
35 #endif /* CCAN_CONTAINER_OF_H */