linux/include/linux/kconfig.h

55 lines
1.9 KiB
C

#ifndef __LINUX_KCONFIG_H
#define __LINUX_KCONFIG_H
#include <generated/autoconf.h>
/*
* Helper macros to use CONFIG_ options in C/CPP expressions. Note that
* these only work with boolean and tristate options.
*/
/*
* Getting something that works in C and CPP for an arg that may or may
* not be defined is tricky. Here, if we have "#define CONFIG_BOOGER 1"
* we match on the placeholder define, insert the "0," for arg1 and generate
* the triplet (0, 1, 0). Then the last step cherry picks the 2nd arg (a one).
* When CONFIG_BOOGER is not defined, we generate a (... 1, 0) pair, and when
* the last step cherry picks the 2nd arg, we get a zero.
*/
#define __ARG_PLACEHOLDER_1 0,
#define config_enabled(cfg) _config_enabled(cfg)
#define _config_enabled(value) __config_enabled(__ARG_PLACEHOLDER_##value)
#define __config_enabled(arg1_or_junk) ___config_enabled(arg1_or_junk 1, 0)
#define ___config_enabled(__ignored, val, ...) val
/*
* IS_BUILTIN(CONFIG_FOO) evaluates to 1 if CONFIG_FOO is set to 'y', 0
* otherwise. For boolean options, this is equivalent to
* IS_ENABLED(CONFIG_FOO).
*/
#define IS_BUILTIN(option) config_enabled(option)
/*
* IS_MODULE(CONFIG_FOO) evaluates to 1 if CONFIG_FOO is set to 'm', 0
* otherwise.
*/
#define IS_MODULE(option) config_enabled(option##_MODULE)
/*
* IS_REACHABLE(CONFIG_FOO) evaluates to 1 if the currently compiled
* code can call a function defined in code compiled based on CONFIG_FOO.
* This is similar to IS_ENABLED(), but returns false when invoked from
* built-in code when CONFIG_FOO is set to 'm'.
*/
#define IS_REACHABLE(option) (config_enabled(option) || \
(config_enabled(option##_MODULE) && config_enabled(MODULE)))
/*
* IS_ENABLED(CONFIG_FOO) evaluates to 1 if CONFIG_FOO is set to 'y' or 'm',
* 0 otherwise.
*/
#define IS_ENABLED(option) \
(IS_BUILTIN(option) || IS_MODULE(option))
#endif /* __LINUX_KCONFIG_H */