LXR linux/include/linux/kconfig.h

   1#ifndef __LINUX_KCONFIG_H
   2#define __LINUX_KCONFIG_H
   3
   4#include <generated/autoconf.h>
   5
   6/*
   7 * Helper macros to use CONFIG_ options in C/CPP expressions. Note that
   8 * these only work with boolean and tristate options.
   9 */
  10
  11/*
  12 * Getting something that works in C and CPP for an arg that may or may
  13 * not be defined is tricky.  Here, if we have "#define CONFIG_BOOGER 1"
  14 * we match on the placeholder define, insert the "0," for arg1 and generate
  15 * the triplet (0, 1, 0).  Then the last step cherry picks the 2nd arg (a one).
  16 * When CONFIG_BOOGER is not defined, we generate a (... 1, 0) pair, and when
  17 * the last step cherry picks the 2nd arg, we get a zero.
  18 */
  19#define __ARG_PLACEHOLDER_1 0,
  20#define config_enabled(cfg) _config_enabled(cfg)
  21#define _config_enabled(value) __config_enabled(__ARG_PLACEHOLDER_##value)
  22#define __config_enabled(arg1_or_junk) ___config_enabled(arg1_or_junk 1, 0)
  23#define ___config_enabled(__ignored, val, ...) val
  24
  25/*
  26 * IS_ENABLED(CONFIG_FOO) evaluates to 1 if CONFIG_FOO is set to 'y' or 'm',
  27 * 0 otherwise.
  28 *
  29 */
  30#define IS_ENABLED(option) \
  31        (config_enabled(option) || config_enabled(option##_MODULE))
  32
  33/*
  34 * IS_BUILTIN(CONFIG_FOO) evaluates to 1 if CONFIG_FOO is set to 'y', 0
  35 * otherwise. For boolean options, this is equivalent to
  36 * IS_ENABLED(CONFIG_FOO).
  37 */
  38#define IS_BUILTIN(option) config_enabled(option)
  39
  40/*
  41 * IS_MODULE(CONFIG_FOO) evaluates to 1 if CONFIG_FOO is set to 'm', 0
  42 * otherwise.
  43 */
  44#define IS_MODULE(option) config_enabled(option##_MODULE)
  45
  46#endif /* __LINUX_KCONFIG_H */
  47