Redo tail closer to the original design. Add more tests for large data sets. (Still no -f support yet.)

2 files changed, 12 insertions, 1 deletions

diff --git a/lib/lib.h b/lib/lib.h
index 09a68252..a71582c7 100644
--- a/lib/lib.h
+++ b/lib/lib.h
@@ -36,7 +36,8 @@ struct double_list {
 };
 
 void llist_traverse(void *list, void (*using)(void *data));
-void *llist_pop(void *list);  // actually void **list, but the compiler's dumb
+void *llist_pop(void *list);  // actually void **list
+void *dlist_pop(void *list);  // actually struct double_list **list
 void dlist_add_nomalloc(struct double_list **list, struct double_list *new);
 struct double_list *dlist_add(struct double_list **list, char *data);
 
diff --git a/lib/llist.c b/lib/llist.c
index 7b41fd08..596da40f 100644
--- a/lib/llist.c
+++ b/lib/llist.c
@@ -33,6 +33,16 @@ void *llist_pop(void *list)
   return (void *)next;
 }
 
+void *dlist_pop(void *list)
+{
+  struct double_list **pdlist = (struct double_list **)list, *dlist = *pdlist;
+
+  dlist->next->prev = dlist->prev;
+  dlist->prev->next = *pdlist = dlist->next;
+
+  return dlist;
+}
+
 void dlist_add_nomalloc(struct double_list **list, struct double_list *new)
 {
   if (*list) {