include/linux/stddef.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #ifndef _LINUX_STDDEF_H
   3 #define _LINUX_STDDEF_H
   4
   5 #include <uapi/linux/stddef.h>
   6
   7 #undef NULL
   8 #define NULL ((void *)0)
   9
  10 enum {
  11         false   = 0,
  12         true    = 1
  13 };
  14
  15 #undef offsetof
  16 #ifdef __compiler_offsetof
  17 #define offsetof(TYPE, MEMBER)  __compiler_offsetof(TYPE, MEMBER)
  18 #else
  19 #define offsetof(TYPE, MEMBER)  ((size_t)&((TYPE *)0)->MEMBER)
  20 #endif
  21
  22 /**
  23  * sizeof_field(TYPE, MEMBER)
  24  *
  25  * @TYPE: The structure containing the field of interest
  26  * @MEMBER: The field to return the size of
  27  */
  28 #define sizeof_field(TYPE, MEMBER) sizeof((((TYPE *)0)->MEMBER))
  29
  30 /**
  31  * offsetofend(TYPE, MEMBER)
  32  *
  33  * @TYPE: The type of the structure
  34  * @MEMBER: The member within the structure to get the end offset of
  35  */
  36 #define offsetofend(TYPE, MEMBER) \
  37         (offsetof(TYPE, MEMBER) + sizeof_field(TYPE, MEMBER))
  38
  39 #endif