1 files changed, 26 insertions, 1 deletions
diff --git a/lichen.h b/lichen.h
index fe68d52..b30c8cb 100644
--- a/lichen.h
+++ b/lichen.h
@@ -1,9 +1,10 @@
 #ifndef LICHEN_H
 #define LICHEN_H
 
+#include <stdlib.h>
 #include <stdint.h>
 
-// random number generation
+/* --===== random number generation =====-- */
 typedef struct li_rand32_t {
   uint32_t (*rand)(void *);
   void *state;
@@ -21,4 +22,28 @@ void li_xorshift32_seed(struct li_xorshift32_t *xor, uint32_t seed);
 uint32_t li_xorshift32(void *s);
 
 
+/* --===== generic linked lists =====-- */
+
+
+typedef struct li_llnode_t {
+  int tag;
+  void *data;
+  struct li_llnode_t *next;
+} li_llnode_t;
+
+
+li_llnode_t * li_alloc_llnode();
+li_llnode_t * li_copy_llnode(li_llnode_t *n);
+void li_free_llnode(li_llnode_t *n, void (*free_data)(void*));
+
+
+typedef struct li_ll_t {
+  int tag;
+  size_t count;
+  li_llnode_t *head;
+} li_ll_t;
+
+
+
+
 #endif