From 8172a163cd8ae41424cf1690b2ac1840c247a1bd Mon Sep 17 00:00:00 2001
From: Greg Burd <greg@burd.me>
Date: Sun, 17 Mar 2024 14:12:56 -0400
Subject: [PATCH] fixing

---
 examples/slm.c | 16 ++++++++++------
 include/sl.h   | 16 +++++++++-------
 2 files changed, 19 insertions(+), 13 deletions(-)

diff --git a/examples/slm.c b/examples/slm.c
index 3fa44fd..67a6458 100644
--- a/examples/slm.c
+++ b/examples/slm.c
@@ -48,7 +48,7 @@ int main() {
 #define STATIC_INIT
 #ifdef STATIC_INIT
   skip_t _list = SKIP_HEAD_DEFAULT_INITIALIZER(__skip_cmp_entry);
-  _list.slh_tail = (struct entry *)_list.slh_head; // TODO...
+  _list.slh_tail = (struct entry *)&_list.slh_head; // TODO...
   skip_t *list = &_list;
 #else /* Dynamic allocation, init. */
   skip_t *list = (skip_t *)malloc(sizeof(skip_t));
@@ -56,13 +56,17 @@ int main() {
 #endif
 
   /* Insert 10 key/value pairs into the list. */
+  struct entry *n;
   for (int i = 0; i < 10; i++) {
-    struct entry *n;
-    SKIP_ALLOC_NODE(list, n, entry, entries);
-    n->key = i;
-    n->value = i;
-    SKIP_INSERT(list, entry, n, entries);
+      SKIP_ALLOC_NODE(list, n, entry, entries);
+      n->key = i;
+      n->value = i;
+      SKIP_INSERT(list, entry, n, entries);
   }
+  SKIP_ALLOC_NODE(list, n, entry, entries);
+  n->key = -1;
+  n->value = -1;
+  SKIP_INSERT(list, entry, n, entries);
 
 #if 0
   /* Delete a specific element in the list. */
diff --git a/include/sl.h b/include/sl.h
index 22c256f..d8c7104 100644
--- a/include/sl.h
+++ b/include/sl.h
@@ -217,7 +217,7 @@ struct sl_trace {
     (var) = (struct type *)calloc(1, sizeof(struct type) + amt + 3);	\
     if ((var) != NULL) {						\
       (var)->field.sle_prev = (struct type *)(var) + sizeof(struct type); \
-      (var)->field.sle_next = (struct type **)(var) + sizeof(struct type) + (sizeof(struct type *) * 3); \
+      (var)->field.sle_next = (struct type **)((var)->field.sle_prev + (sizeof(void *) * 3)); \
       ARRAY_SET_SIZE((var)->field.sle_next, (head)->max);		\
       ARRAY_SET_LENGTH((var)->field.sle_next, 0);			\
     }									\
@@ -235,13 +235,14 @@ struct sl_trace {
 
 #define SKIP_INSERT(head, type, listelm, field) do {			\
     struct type *__elm = SKIP_FIRST(head);				\
-    unsigned int __i = (head)->level;					\
+    unsigned int __i;							\
     struct type **__path;						\
-    if (__elm == NULL) {						\
+    if ((listelm) == NULL) break;					\
+    if (__elm == NULL) { \
       /* Empty list, setup header and add first element. */		\
-      ARRAY_ALLOC((head)->slh_head, type, (head)->max);	\
-      ARRAY_FORALL(__j, (head)->slh_head) {				\
-	(head)->slh_head[__j] = (head)->slh_tail;			\
+      ARRAY_ALLOC((head)->slh_head, type, (head)->max);			\
+      ARRAY_FORALL(__i, (head)->slh_head) {				\
+	(head)->slh_head[__i] = (head)->slh_tail;			\
       }									\
       (head)->slh_head[0] = (listelm);					\
       (head)->slh_tail = (listelm);					\
@@ -250,11 +251,12 @@ struct sl_trace {
       (head)->length = 1;						\
       break;								\
     }									\
+    __i = (head)->level;						\
     ARRAY_ALLOC(__path, type, (head)->max);				\
     if (__path == NULL) break; /* ENOMEM */				\
     /* Find the position in the list where this element belongs. */	\
     do {								\
-      while(__elm && (head)->cmp((head), __elm->field.sle_next[__i], __elm, (head)->aux) < 0) \
+      while(__elm && (head)->cmp((head), __elm->field.sle_next[__i], (listelm), (head)->aux) < 0) \
 	__elm = __elm->field.sle_next[__i];				\
       __path[__i] = __elm;						\
     } while(__i--);							\