diff options
Diffstat (limited to 'lib/util.h')
| -rw-r--r-- | lib/util.h | 10 |
1 files changed, 10 insertions, 0 deletions
diff --git a/lib/util.h b/lib/util.h index 9eca8ec9a..5147ffc55 100644 --- a/lib/util.h +++ b/lib/util.h @@ -82,6 +82,16 @@ extern const char *program_name; #define CONTAINER_OF(POINTER, STRUCT, MEMBER) \ ((STRUCT *) (void *) ((char *) (POINTER) - offsetof (STRUCT, MEMBER))) +/* Given POINTER, the address of the given MEMBER within an object of the type + * that that OBJECT points to, returns OBJECT as a "void *" pointer. OBJECT + * must be an lvalue. + * + * This is the same as CONTAINER_OF except that it infers the structure type + * from the type of '*OBJECT'. */ +#define OBJECT_CONTAINING(POINTER, OBJECT, MEMBER) \ + ((void *) ((char *) (POINTER) \ + - ((char *) &(OBJECT)->MEMBER - (char *) (OBJECT)))) + #ifdef __cplusplus extern "C" { #endif |