From ced952a4c6244134f1578f1ef69be3ed7f09c81d Mon Sep 17 00:00:00 2001
From: Geoffrey McRae <geoff@hostfission.com>
Date: Wed, 12 Jan 2022 09:33:36 +1100
Subject: [PATCH] [client] ll: add new functionallity to allow removal of items

---
 client/include/ll.h | 80 +++++++++++++++++++++++++++++++++++++++++++--
 client/src/ll.c     | 39 +++-------------------
 2 files changed, 82 insertions(+), 37 deletions(-)

diff --git a/client/include/ll.h b/client/include/ll.h
index a8a24dfe..a9b1e69a 100644
--- a/client/include/ll.h
+++ b/client/include/ll.h
@@ -18,8 +18,27 @@
  * Temple Place, Suite 330, Boston, MA 02111-1307 USA
  */
 
+#ifndef _H_LL_
+#define _H_LL_
+
 #include <stdbool.h>
-struct ll;
+
+#include "common/locking.h"
+
+struct ll_item
+{
+  void           * data;
+  struct ll_item * prev, * next;
+};
+
+struct ll
+{
+  struct ll_item * head;
+  struct ll_item * tail;
+  struct ll_item * pos;
+  unsigned int count;
+  LG_Lock lock;
+};
 
 struct ll *  ll_new();
 void         ll_free     (struct ll * list);
@@ -27,7 +46,62 @@ void         ll_push     (struct ll * list, void * data);
 bool         ll_shift    (struct ll * list, void ** data);
 bool         ll_peek_head(struct ll * list, void ** data);
 bool         ll_peek_tail(struct ll * list, void ** data);
-unsigned int ll_count    (struct ll * list);
 
-void         ll_reset    (struct ll * list);
 bool         ll_walk     (struct ll * list, void ** data);
+
+#define ll_lock(ll) LG_LOCK((ll)->lock)
+#define ll_unlock(ll) LG_UNLOCK((ll)->lock)
+
+#define ll_forEachNL(ll, item, v) \
+  for(struct ll_item * item = (ll)->head, * _ = (ll)->head->next; (item);) \
+    for((v) = (__typeof__(v))((item)->data); (item); (item) = _, \
+        _ = _ ? _->next : NULL, (v) = (__typeof__(v))((item)->data))
+
+static inline unsigned int ll_count(struct ll * list)
+{
+  return list->count;
+}
+
+static inline void ll_reset (struct ll * list)
+{
+  LG_LOCK(list->lock);
+  list->pos = NULL;
+  LG_UNLOCK(list->lock);
+}
+
+static inline void ll_removeNL(struct ll * list, struct ll_item * item)
+{
+  --list->count;
+
+  if (list->head == item)
+    list->head = item->next;
+
+  if (list->tail == item)
+    list->tail = item->prev;
+
+  if (item->prev)
+    item->prev->next = item->next;
+
+  if (item->next)
+    item->next->prev = item->prev;
+
+  list->pos = NULL;
+}
+
+static inline bool ll_removeData(struct ll * list, void * match)
+{
+  void * data;
+  ll_lock(list);
+  ll_forEachNL(list, item, data)
+    if (data == match)
+    {
+      ll_removeNL(list, item);
+      ll_unlock(list);
+      return true;
+    }
+  ll_unlock(list);
+
+  return false;
+}
+
+#endif
diff --git a/client/src/ll.c b/client/src/ll.c
index a5587465..9642694a 100644
--- a/client/src/ll.c
+++ b/client/src/ll.c
@@ -24,21 +24,6 @@
 #include "common/locking.h"
 #include <stdlib.h>
 
-struct ll_item
-{
-  void           * data;
-  struct ll_item * next;
-};
-
-struct ll
-{
-  struct ll_item * head;
-  struct ll_item * tail;
-  struct ll_item * pos;
-  unsigned int count;
-  LG_Lock lock;
-};
-
 struct ll * ll_new(void)
 {
   struct ll * list = malloc(sizeof(*list));
@@ -70,14 +55,18 @@ void ll_push(struct ll * list, void * data)
 
   if (!list->head)
   {
+    item->prev = NULL;
     list->head = item;
     list->tail = item;
     LG_UNLOCK(list->lock);
     return;
   }
 
+  item->prev = list->tail;
+
   list->tail->next = item;
   list->tail       = item;
+
   LG_UNLOCK(list->lock);
 }
 
@@ -90,13 +79,8 @@ bool ll_shift(struct ll * list, void ** data)
     return false;
   }
 
-  --list->count;
   struct ll_item * item = list->head;
-  list->head = item->next;
-  list->pos  = NULL;
-  if (list->tail == item)
-    list->tail = NULL;
-
+  ll_removeNL(list, item);
   LG_UNLOCK(list->lock);
 
   if (data)
@@ -136,19 +120,6 @@ bool ll_peek_tail(struct ll * list, void ** data)
   return true;
 }
 
-unsigned int ll_count(struct ll * list)
-{
-  return list->count;
-}
-
-void ll_reset (struct ll * list)
-{
-  LG_LOCK(list->lock);
-  list->pos = NULL;
-  LG_UNLOCK(list->lock);
-}
-
-
 bool ll_walk(struct ll * list, void ** data)
 {
   LG_LOCK(list->lock);