From 048d2cc363fe786e765f61634dd916650faed927 Mon Sep 17 00:00:00 2001
From: Bert Belder <bertbelder@gmail.com>
Date: Thu, 14 Sep 2017 16:37:31 +0200
Subject: [PATCH] queue: add internal queue_move_first() and queue_move_last()
 APIs

---
 src/queue.c | 21 +++++++++++++++++----
 src/queue.h |  2 ++
 2 files changed, 19 insertions(+), 4 deletions(-)

diff --git a/src/queue.c b/src/queue.c
index 0ee814e..3ad927e 100644
--- a/src/queue.c
+++ b/src/queue.c
@@ -12,6 +12,11 @@ void queue_node_init(queue_node_t* node) {
   node->next = node;
 }
 
+static inline void _queue_detach(queue_node_t* node) {
+  node->prev->next = node->next;
+  node->next->prev = node->prev;
+}
+
 queue_node_t* queue_first(const queue_t* queue) {
   return !queue_empty(queue) ? queue->head.next : NULL;
 }
@@ -34,11 +39,19 @@ void queue_append(queue_t* queue, queue_node_t* node) {
   queue->head.prev = node;
 }
 
+void queue_move_first(queue_t* queue, queue_node_t* node) {
+  _queue_detach(node);
+  queue_prepend(queue, node);
+}
+
+void queue_move_last(queue_t* queue, queue_node_t* node) {
+  _queue_detach(node);
+  queue_append(queue, node);
+}
+
 void queue_remove(queue_node_t* node) {
-  node->prev->next = node->next;
-  node->next->prev = node->prev;
-  node->prev = node;
-  node->next = node;
+  _queue_detach(node);
+  queue_node_init(node);
 }
 
 bool queue_empty(const queue_t* queue) {
diff --git a/src/queue.h b/src/queue.h
index 4061b0b..ce30a6d 100644
--- a/src/queue.h
+++ b/src/queue.h
@@ -24,6 +24,8 @@ EPOLL_INTERNAL queue_node_t* queue_last(const queue_t* queue);
 
 EPOLL_INTERNAL void queue_prepend(queue_t* queue, queue_node_t* node);
 EPOLL_INTERNAL void queue_append(queue_t* queue, queue_node_t* node);
+EPOLL_INTERNAL void queue_move_first(queue_t* queue, queue_node_t* node);
+EPOLL_INTERNAL void queue_move_last(queue_t* queue, queue_node_t* node);
 EPOLL_INTERNAL void queue_remove(queue_node_t* node);
 
 EPOLL_INTERNAL bool queue_empty(const queue_t* queue);