/* GLIB - Library of useful routines for C programming
- * Copyright (C) 1999 Free Software Foundation, Inc.
+ * Copyright (C) 1995-1997 Peter Mattis, Spencer Kimball and Josh MacDonald
+ *
+ * GQueue: Double ended queue implementation, piggy backed on GList.
+ * Copyright (C) 1998 Tim Janik
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* Boston, MA 02111-1307, USA.
*/
+/*
+ * MT safe
+ */
-#ifdef HAVE_CONFIG_H
-# include <config.h>
-#endif
+#include "glib.h"
-#include <glib.h>
+G_LOCK_DEFINE_STATIC (queue_memchunk);
+static GMemChunk *queue_memchunk = NULL;
+static GTrashStack *free_queue_nodes = NULL;
+GQueue*
+g_queue_create (void)
+{
+ GQueue *queue;
+ G_LOCK (queue_memchunk);
+ queue = g_trash_stack_pop (&free_queue_nodes);
-GQueue *
-g_queue_new (void)
-{
- GQueue *q = g_new (GQueue, 1);
+ if (!queue)
+ {
+ if (!queue_memchunk)
+ queue_memchunk = g_mem_chunk_new ("GLib GQueue chunk",
+ sizeof (GNode),
+ sizeof (GNode) * 128,
+ G_ALLOC_ONLY);
+ queue = g_chunk_new (GQueue, queue_memchunk);
+ }
+ G_UNLOCK (queue_memchunk);
- q->list = q->list_end = NULL;
- q->list_size = 0;
+ queue->head = NULL;
+ queue->tail = NULL;
+ queue->length = 0;
- return q;
+ return queue;
}
-
void
-g_queue_free (GQueue *q)
+g_queue_free (GQueue *queue)
{
- if (q)
- {
- if (q->list)
- g_list_free (q->list);
- g_free (q);
- }
-}
+ g_return_if_fail (queue != NULL);
+ g_list_free (queue->head);
-guint
-g_queue_get_size (GQueue *q)
-{
- return (q == NULL) ? 0 : q->list_size;
+ G_LOCK (queue_memchunk);
+ g_trash_stack_push (&free_queue_nodes, queue);
+ G_UNLOCK (queue_memchunk);
}
-
void
-g_queue_push_front (GQueue *q, gpointer data)
+g_queue_push_head (GQueue *queue,
+ gpointer data)
{
- if (q)
- {
- q->list = g_list_prepend (q->list, data);
+ g_return_if_fail (queue != NULL);
- if (q->list_end == NULL)
- q->list_end = q->list;
+ queue->head = g_list_prepend (queue->head, data);
+ if (!queue->tail)
+ queue->tail = queue->head;
+ queue->length++;
+}
- q->list_size++;
- }
+void
+g_queue_push_head_link (GQueue *queue,
+ GList *link)
+{
+ g_return_if_fail (queue != NULL);
+ g_return_if_fail (link != NULL);
+ g_return_if_fail (link->prev != NULL);
+ g_return_if_fail (link->next != NULL);
+
+ link->next = queue->head;
+ if (queue->head)
+ queue->head->prev = link;
+ else
+ queue->tail = link;
+ queue->head = link;
+ queue->length++;
}
+void
+g_queue_push_tail (GQueue *queue,
+ gpointer data)
+{
+ g_return_if_fail (queue != NULL);
+
+ queue->tail = g_list_append (queue->tail, data);
+ if (queue->tail->next)
+ queue->tail = queue->tail->next;
+ else
+ queue->head = queue->tail;
+ queue->length++;
+}
void
-g_queue_push_back (GQueue *q, gpointer data)
+g_queue_push_tail_link (GQueue *queue,
+ GList *link)
{
- if (q)
+ g_return_if_fail (queue != NULL);
+ g_return_if_fail (link != NULL);
+ g_return_if_fail (link->prev != NULL);
+ g_return_if_fail (link->next != NULL);
+
+ link->prev = queue->tail;
+ if (queue->tail)
+ queue->tail->next = link;
+ else
+ queue->head = link;
+ queue->tail = link;
+ queue->length++;
+}
+
+gpointer
+g_queue_pop_head (GQueue *queue)
+{
+ g_return_val_if_fail (queue != NULL, NULL);
+
+ if (queue->head)
{
- q->list_end = g_list_append (q->list_end, data);
+ GList *node = queue->head;
+ gpointer data = node->data;
- if (! q->list)
- q->list = q->list_end;
+ queue->head = node->next;
+ if (queue->head)
+ queue->head->prev = NULL;
else
- q->list_end = q->list_end->next;
+ queue->tail = NULL;
+ g_list_free_1 (node);
+ queue->length--;
- q->list_size++;
+ return data;
}
-}
+ return NULL;
+}
-gpointer
-g_queue_pop_front (GQueue *q)
+GList*
+g_queue_pop_head_link (GQueue *queue)
{
- gpointer data = NULL;
+ g_return_val_if_fail (queue != NULL, NULL);
- if ((q) && (q->list))
+ if (queue->head)
{
- GList *node;
+ GList *node = queue->head;
- node = q->list;
- data = node->data;
-
- if (! node->next)
- {
- q->list = q->list_end = NULL;
- q->list_size = 0;
- }
+ queue->head = node->next;
+ if (queue->head)
+ {
+ queue->head->prev = NULL;
+ node->next = NULL;
+ }
else
- {
- q->list = node->next;
- q->list->prev = NULL;
- q->list_size--;
- }
+ queue->tail = NULL;
+ queue->length--;
- g_list_free_1 (node);
+ return node;
}
- return data;
+ return NULL;
}
-
gpointer
-g_queue_pop_back (GQueue *q)
+g_queue_pop_tail (GQueue *queue)
{
- gpointer data = NULL;
+ g_return_val_if_fail (queue != NULL, NULL);
- if ((q) && (q->list))
+ if (queue->tail)
{
- GList *node;
+ GList *node = queue->tail;
+ gpointer data = node->data;
+
+ queue->tail = node->prev;
+ if (queue->tail)
+ queue->tail->next = NULL;
+ else
+ queue->head = NULL;
+ queue->length--;
+ g_list_free_1 (node);
- node = q->list_end;
- data = node->data;
+ return data;
+ }
+
+ return NULL;
+}
- if (! node->prev)
+GList*
+g_queue_pop_tail_link (GQueue *queue)
+{
+ g_return_val_if_fail (queue != NULL, NULL);
+
+ if (queue->tail)
+ {
+ GList *node = queue->tail;
+
+ queue->tail = node->prev;
+ if (queue->tail)
{
- q->list = q->list_end = NULL;
- q->list_size = 0;
- }
+ queue->tail->next = NULL;
+ node->prev = NULL;
+ }
else
- {
- q->list_end = node->prev;
- q->list_end->next = NULL;
- q->list_size--;
- }
-
- g_list_free_1 (node);
+ queue->head = NULL;
+ queue->length--;
+
+ return node;
}
+
+ return NULL;
+}
- return data;
+gboolean
+g_queue_is_empty (GQueue *queue)
+{
+ g_return_val_if_fail (queue != NULL, TRUE);
+
+ return queue->head == NULL;
}
+gpointer
+g_queue_peek_head (GQueue *queue)
+{
+ g_return_val_if_fail (queue != NULL, NULL);
+ return queue->head ? queue->head->data : NULL;
+}
+
+gpointer
+g_queue_peek_tail (GQueue *queue)
+{
+ g_return_val_if_fail (queue != NULL, NULL);
+
+ return queue->tail ? queue->tail->data : NULL;
+}