fixing slist api and implementation

1 files changed, 59 insertions, 46 deletions

diff --git a/src/util/container_slist.c b/src/util/container_slist.c
index c279bb2ea..874068bdb 100644
--- a/src/util/container_slist.c
+++ b/src/util/container_slist.c
@@ -29,19 +29,21 @@
 
 struct GNUNET_CONTAINER_SList_Elem
 {
-  void *elem;
+  struct GNUNET_CONTAINER_SList_Elem *next;
+  const void *elem;
   size_t len;
   int disp;
-  struct GNUNET_CONTAINER_SList_Elem *next;
 };
 
 struct GNUNET_CONTAINER_SList
 {
-  struct GNUNET_CONTAINER_SList_Elem head;
+  struct GNUNET_CONTAINER_SList_Elem *head;
+  unsigned int length;
 };
 
 struct GNUNET_CONTAINER_SList_Iterator
 {
+  struct GNUNET_CONTAINER_SList *list;
   struct GNUNET_CONTAINER_SList_Elem *last;
   struct GNUNET_CONTAINER_SList_Elem *elem;
 };
@@ -59,20 +61,23 @@ create_elem (int disp, const void *buf, size_t len)
 {
   struct GNUNET_CONTAINER_SList_Elem *e;
 
-  e = GNUNET_malloc (sizeof (struct GNUNET_CONTAINER_SList_Elem));
-  e->disp = disp;
   if (disp == GNUNET_MEM_DISP_TRANSIENT)
     {
-      e->elem = GNUNET_malloc (len);
-      memcpy (e->elem, buf, len);
+      e = GNUNET_malloc (sizeof (struct GNUNET_CONTAINER_SList_Elem) + len);
+      memcpy (&e[1], buf, len);
+      e->elem = (const void*) &e[1];
     }
   else
-    e->elem = (void *) buf;
+    {
+      e = GNUNET_malloc (sizeof (struct GNUNET_CONTAINER_SList_Elem));
+      e->elem = buf;
+    }
+  e->disp = disp;
   e->len = len;
-
   return e;
 }
 
+
 /**
  * Add a new element to the list
  * @param l list
@@ -87,10 +92,12 @@ GNUNET_CONTAINER_slist_add (struct GNUNET_CONTAINER_SList *l, int disp,
   struct GNUNET_CONTAINER_SList_Elem *e;
 
   e = create_elem (disp, buf, len);
-  e->next = l->head.next;
-  l->head.next = e;
+  e->next = l->head;
+  l->head = e;
+  l->length++;
 }
 
+
 /**
  * Create a new singly linked list
  * @return the new list
@@ -98,15 +105,7 @@ GNUNET_CONTAINER_slist_add (struct GNUNET_CONTAINER_SList *l, int disp,
 struct GNUNET_CONTAINER_SList *
 GNUNET_CONTAINER_slist_create ()
 {
-  struct GNUNET_CONTAINER_SList *ret;
-
-  ret = GNUNET_malloc (sizeof (struct GNUNET_CONTAINER_SList));
-  if (NULL == ret)
-    return NULL;
-
-  memset (&ret->head, 0, sizeof (struct GNUNET_CONTAINER_SList));
-
-  return ret;
+  return GNUNET_malloc (sizeof (struct GNUNET_CONTAINER_SList));
 }
 
 /**
@@ -120,22 +119,24 @@ GNUNET_CONTAINER_slist_destroy (struct GNUNET_CONTAINER_SList *l)
   GNUNET_free (l);
 }
 
+
 /**
  * Return the beginning of a list
  * @param l list
  * @return iterator pointing to the beginning
  */
-const struct GNUNET_CONTAINER_SList_Iterator *
-GNUNET_CONTAINER_slist_begin (const struct GNUNET_CONTAINER_SList *l)
+struct GNUNET_CONTAINER_SList_Iterator *
+GNUNET_CONTAINER_slist_begin (struct GNUNET_CONTAINER_SList *l)
 {
   struct GNUNET_CONTAINER_SList_Iterator *ret;
 
   ret = GNUNET_malloc (sizeof (struct GNUNET_CONTAINER_SList_Iterator));
-  ret->elem = l->head.next;
-  ret->last = (struct GNUNET_CONTAINER_SList_Elem *) &l->head;
+  ret->elem = l->head;
+  ret->list = l;
   return ret;
 }
 
+
 /**
  * Clear a list
  * @param l list
@@ -143,22 +144,24 @@ GNUNET_CONTAINER_slist_begin (const struct GNUNET_CONTAINER_SList *l)
 void
 GNUNET_CONTAINER_slist_clear (struct GNUNET_CONTAINER_SList *l)
 {
-  struct GNUNET_CONTAINER_SList_Elem *e, *n;
+  struct GNUNET_CONTAINER_SList_Elem *e;
+  struct GNUNET_CONTAINER_SList_Elem *n;
 
-  e = l->head.next;
+  e = l->head;
   while (e != NULL)
     {
-      if (e->disp != GNUNET_MEM_DISP_STATIC)
-        GNUNET_free (e->elem);
       n = e->next;
       GNUNET_free (e);
       e = n;
     }
-  l->head.next = NULL;
+  l->head = NULL;
+  l->length = 0;
 }
 
+
 /**
  * Check if a list contains a certain element
+ *
  * @param l list
  * @param buf payload buffer to find
  * @param lenght of the payload
@@ -169,13 +172,14 @@ GNUNET_CONTAINER_slist_contains (const struct GNUNET_CONTAINER_SList *l,
 {
   struct GNUNET_CONTAINER_SList_Elem *e;
 
-  for (e = l->head.next; e != NULL; e = e->next)
-    if (e->len == len && memcmp (buf, e->elem, len) == 0)
+  for (e = l->head; e != NULL; e = e->next)
+    if ( (e->len == len) && 
+         (memcmp (buf, e->elem, len) == 0) )
       return GNUNET_YES;
-
   return GNUNET_NO;
 }
 
+
 /**
  * Count the elements of a list
  * @param l list
@@ -184,17 +188,13 @@ GNUNET_CONTAINER_slist_contains (const struct GNUNET_CONTAINER_SList *l,
 int
 GNUNET_CONTAINER_slist_count (const struct GNUNET_CONTAINER_SList *l)
 {
-  int n;
-  struct GNUNET_CONTAINER_SList_Elem *e;
-
-  for (n = 0, e = l->head.next; e != NULL; e = e->next)
-    n++;
-
-  return n;
+  return l->length;
 }
 
+
 /**
  * Remove an element from the list
+ *
  * @param i iterator that points to the element to be removed
  */
 void
@@ -203,13 +203,16 @@ GNUNET_CONTAINER_slist_erase (struct GNUNET_CONTAINER_SList_Iterator *i)
   struct GNUNET_CONTAINER_SList_Elem *next;
 
   next = i->elem->next;
-  i->last->next = next;
-  if (i->elem->disp != GNUNET_MEM_DISP_STATIC)
-    GNUNET_free (i->elem->elem);
+  if (i->last != NULL)
+    i->last->next = next;
+  else
+    i->list->head = next;
   GNUNET_free (i->elem);
+  i->list->length--;
   i->elem = next;
 }
 
+
 /**
  * Insert an element into a list at a specific position
  * @param before where to insert the new element
@@ -225,9 +228,14 @@ GNUNET_CONTAINER_slist_insert (struct GNUNET_CONTAINER_SList_Iterator *before,
 
   e = create_elem (disp, buf, len);
   e->next = before->elem;
-  before->last->next = e;
+  if (before->last != NULL)
+    before->last->next = e;
+  else
+    before->list->head = e;
+  before->list->length++;
 }
 
+
 /**
  * Advance an iterator to the next element
  * @param i iterator
@@ -239,11 +247,13 @@ GNUNET_CONTAINER_slist_next (struct GNUNET_CONTAINER_SList_Iterator *i)
   i->last = i->elem;
   i->elem = i->elem->next;
 
-  return i->elem != NULL;
+  return (i->elem != NULL) ? GNUNET_YES : GNUNET_NO;
 }
 
+
 /**
  * Check if an iterator points beyond the end of a list
+ *
  * @param i iterator
  * @return GNUNET_YES if the end has been reached, GNUNET_NO if the iterator
  *         points to a valid element
@@ -251,16 +261,17 @@ GNUNET_CONTAINER_slist_next (struct GNUNET_CONTAINER_SList_Iterator *i)
 int
 GNUNET_CONTAINER_slist_end (struct GNUNET_CONTAINER_SList_Iterator *i)
 {
-  return i->elem == NULL;
+  return (i->elem == NULL) ? GNUNET_YES : GNUNET_NO;
 }
 
+
 /**
  * Retrieve the element at a specific position in a list
  * @param i iterator
  * @param len payload length
  * @return payload
  */
-void *
+const void *
 GNUNET_CONTAINER_slist_get (const struct GNUNET_CONTAINER_SList_Iterator *i,
                             size_t * len)
 {
@@ -268,3 +279,5 @@ GNUNET_CONTAINER_slist_get (const struct GNUNET_CONTAINER_SList_Iterator *i,
     *len = i->elem->len;
   return i->elem->elem;
 }
+
+/* end of container_slist.c */