1  #ifndef __KCONFIG_H__
 2  #define __KCONFIG_H__
 3  
 4  #include <config.h>
 5  
 6  /*
 7   * Getting something that works in C and CPP for an arg that may or may
 8   * not be defined is tricky.  Here, if we have "#define CONFIG_BOOGER 1"
 9   * we match on the placeholder define, insert the "0," for arg1 and generate
10   * the triplet (0, 1, 0).  Then the last step cherry picks the 2nd arg (a one).
11   * When CONFIG_BOOGER is not defined, we generate a (... 1, 0) pair, and when
12   * the last step cherry picks the 2nd arg, we get a zero.
13   */
14  #define __ARG_PLACEHOLDER_1 0,
15  #define config_enabled(cfg) _config_enabled(cfg)
16  #define _config_enabled(value) __config_enabled(__ARG_PLACEHOLDER_##value)
17  #define __config_enabled(arg1_or_junk) ___config_enabled(arg1_or_junk 1, 0, 0)
18  #define ___config_enabled(__ignored, val, ...) val
19  
20  #define CONFIG(option) config_enabled(CONFIG_##option)
21  
22  #endif