kernel: add c++ support

include/socks/bitmap.h

@@ -3,6 +3,10 @@
 
 #include <stdbool.h>
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 #define BITS_PER_WORD (8 * sizeof(unsigned long))
 #define __DIV_ROUND_UP(n, d) (((n) + (d) - 1) / (d))
 #define BITMAP_WORDS(nbits) __DIV_ROUND_UP(nbits, BITS_PER_WORD)
@@ -23,4 +27,8 @@ extern unsigned int bitmap_highest_clear(unsigned long *map, unsigned long nbits
 extern unsigned int bitmap_lowest_set(unsigned long *map, unsigned long nbits);
 extern unsigned int bitmap_lowest_clear(unsigned long *map, unsigned long nbits);
 
+#ifdef __cplusplus
+}
+#endif
+
 #endif