diff options
Diffstat (limited to 'include/linux/kconfig.h')
| -rw-r--r-- | include/linux/kconfig.h | 22 |
1 files changed, 18 insertions, 4 deletions
diff --git a/include/linux/kconfig.h b/include/linux/kconfig.h index 067eda0e4b3..be342b94c64 100644 --- a/include/linux/kconfig.h +++ b/include/linux/kconfig.h @@ -4,29 +4,43 @@ #include <generated/autoconf.h> /* - * Helper macros to use CONFIG_ options in C expressions. Note that + * 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_ENABLED(CONFIG_FOO) evaluates to 1 if CONFIG_FOO is set to 'y' or 'm', * 0 otherwise. * */ #define IS_ENABLED(option) \ - (__enabled_ ## option || __enabled_ ## option ## _MODULE) + (config_enabled(option) || config_enabled(option##_MODULE)) /* * 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) __enabled_ ## option +#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) __enabled_ ## option ## _MODULE +#define IS_MODULE(option) config_enabled(option##_MODULE) #endif /* __LINUX_KCONFIG_H */ |