| Message ID | 1454147250-7704-2-git-send-email-zhaoshenglong@huawei.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 1/30/16 3:47 AM, Shannon Zhao wrote: > From: Shannon Zhao <shannon.zhao@linaro.org> > > To support using CONFIG_ options in C/CPP expressions, import kconfig.h > from the Linux v4.3 tag (commit id > 6a13feb9c82803e2b815eca72fa7a9f5561d7861). > Only import IS_ENABLED for Xen since Xen doesn't support loadable > modules. > > CC: Doug Goldstein <cardoe@cardoe.com> > Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org> Reviewed-by: Doug Goldstein <cardoe@cardoe.com> > --- > xen/include/xen/kconfig.h | 31 +++++++++++++++++++++++++++++++ > 1 file changed, 31 insertions(+) > create mode 100644 xen/include/xen/kconfig.h > > diff --git a/xen/include/xen/kconfig.h b/xen/include/xen/kconfig.h > new file mode 100644 > index 0000000..4d58c5b > --- /dev/null > +++ b/xen/include/xen/kconfig.h > @@ -0,0 +1,31 @@ > +#ifndef __XEN_KCONFIG_H > +#define __XEN_KCONFIG_H > + > +#include <generated/autoconf.h> > + > +/* > + * Helper macros to use CONFIG_ options in C/CPP expressions. Note that > + * these only work with boolean option. > + */ > + > +/* > + * 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', 0 > + * otherwise. > + */ > +#define IS_ENABLED(option) config_enabled(option) > + > +#endif /* __XEN_KCONFIG_H */ >
diff --git a/xen/include/xen/kconfig.h b/xen/include/xen/kconfig.h new file mode 100644 index 0000000..4d58c5b --- /dev/null +++ b/xen/include/xen/kconfig.h @@ -0,0 +1,31 @@ +#ifndef __XEN_KCONFIG_H +#define __XEN_KCONFIG_H + +#include <generated/autoconf.h> + +/* + * Helper macros to use CONFIG_ options in C/CPP expressions. Note that + * these only work with boolean option. + */ + +/* + * 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', 0 + * otherwise. + */ +#define IS_ENABLED(option) config_enabled(option) + +#endif /* __XEN_KCONFIG_H */