Fix codeQL scan defects

Author: TheCloudlet

src/map.c

@@ -20,7 +20,7 @@
 
 #include "map.h"
 
-/* FIXME: Avoid relying on key_size and data_size */
+/* TODO: Avoid relying on key_size and data_size */
 struct map_head_t {
     map_node_t *root;
 
@@ -110,7 +110,7 @@ static inline void rb_node_init(map_node_t *node)
         rb_node_set_right((r_node), (x_node));                   \
     } while (0)
 
-/* FIXME: embed cmp (00, 01, 11) into @node pointer as 'right_red' does */
+/* TODO: embed cmp (00, 01, 11) into @node pointer as 'right_red' does */
 typedef struct {
     map_node_t *node;
     map_cmp_t cmp;
@@ -131,7 +131,7 @@ static inline map_node_t *rb_search(map_t rb, const map_node_t *node)
             ret = rb_node_get_right(ret);
             break;
         default:
-            //__UNREACHABLE;
+            assert(0);
             break;
         }
     }
@@ -159,8 +159,7 @@ static void rb_insert(map_t rb, map_node_t *node)
             pathp[1].node = rb_node_get_right(pathp->node);
             break;
         default:
-            assert(cmp != _CMP_EQUAL);
-            //__UNREACHABLE;
+            /* igore duplicate key */
             break;
         }
     }

src/map.h

@@ -22,7 +22,7 @@ typedef struct map_node {
     struct map_node *left, *right_red; /* red-black tree */
 } map_node_t;
 
-/* FIXME: Change to binary representation and utilize a pointer to the node
+/* TODO: Change to binary representation and utilize a pointer to the node
  * embedding comparator values similar to 'right_red'.
  * _CMP_EQUAL   : 00
  * _CMP_GREATER : 01