kernel: add c++ support

include/socks/btree.h

@@ -14,7 +14,7 @@
   - Redistributions in binary form must reproduce the above copyright
     notice, this list of conditions and the following disclaimer in the
     documentation and/or other materials provided with the distribution.
-  
+
   - Neither the name of the copyright holder nor the names of its
     contributors may be used to endorse or promote products derived from this
     software without specific prior written permission.
@@ -25,6 +25,10 @@
 
 #include <stdint.h>
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 /* if your custom structure contains a btree_node_t (i.e. it can be part of a btree),
    you can use this macro to convert a btree_node_t* to a your_type*
 
@@ -94,8 +98,8 @@
 		}                                                                                         \
                                                                                                           \
 		btree_insert_fixup(tree, &node->container_node_member);                                   \
-	} 
-	
+	}
+
 /* defines a node insertion function.
    this function should be used for trees with complex node keys that cannot be directly compared.
    a comparator for your keys must be supplied.
@@ -114,9 +118,9 @@
 
    Which implements the following:
 
-     return -1   if a < b 
-     return  0   if a == b 
-     return  1   if a > b 
+     return -1   if a < b
+     return  0   if a == b
+     return  1   if a > b
 
    You would use the following call to generate an insert function for a tree with this node type:
 
@@ -370,4 +374,8 @@ static inline unsigned short btree_height(btree_node_t *node)
 	return node->b_height;
 }
 
+#ifdef __cplusplus
+}
+#endif
+
 #endif