1 files changed, 122 insertions, 0 deletions
diff --git a/src/nautilus-file-queue.c b/src/nautilus-file-queue.c
new file mode 100644
index 000000000..846b1c4df
--- /dev/null
+++ b/src/nautilus-file-queue.c
@@ -0,0 +1,122 @@
+/*
+   Copyright (C) 2001 Maciej Stachowiak
+  
+   This program is free software; you can redistribute it and/or
+   modify it under the terms of the GNU General Public License as
+   published by the Free Software Foundation; either version 2 of the
+   License, or (at your option) any later version.
+  
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   General Public License for more details.
+  
+   You should have received a copy of the GNU General Public
+   License along with this program; if not, see <http://www.gnu.org/licenses/>.
+
+   Author: Maciej Stachowiak <mjs@noisehavoc.org>
+*/
+
+#include <config.h>
+#include "nautilus-file-queue.h"
+
+#include <glib.h>
+
+struct NautilusFileQueue {
+	GList *head;
+	GList *tail;
+	GHashTable *item_to_link_map;
+};
+
+NautilusFileQueue *
+nautilus_file_queue_new (void)
+{
+	NautilusFileQueue *queue;
+	
+	queue = g_new0 (NautilusFileQueue, 1);
+	queue->item_to_link_map = g_hash_table_new (g_direct_hash, g_direct_equal);
+
+	return queue;
+}
+
+void
+nautilus_file_queue_destroy (NautilusFileQueue *queue)
+{
+	g_hash_table_destroy (queue->item_to_link_map);
+	nautilus_file_list_free (queue->head);
+	g_free (queue);
+}
+
+void
+nautilus_file_queue_enqueue (NautilusFileQueue *queue,
+			     NautilusFile      *file)
+{
+	if (g_hash_table_lookup (queue->item_to_link_map, file) != NULL) {
+		/* It's already on the queue. */
+		return;
+	}
+
+	if (queue->tail == NULL) {
+		queue->head = g_list_append (NULL, file);
+		queue->tail = queue->head;
+	} else {
+		queue->tail = g_list_append (queue->tail, file);
+		queue->tail = queue->tail->next;
+	}
+
+	nautilus_file_ref (file);
+	g_hash_table_insert (queue->item_to_link_map, file, queue->tail);
+}
+
+NautilusFile *
+nautilus_file_queue_dequeue (NautilusFileQueue *queue)
+{
+	NautilusFile *file;
+
+	file = nautilus_file_queue_head (queue);
+	nautilus_file_queue_remove (queue, file);
+
+	return file;
+}
+
+
+void
+nautilus_file_queue_remove (NautilusFileQueue *queue,
+			    NautilusFile *file)
+{
+	GList *link;
+
+	link = g_hash_table_lookup (queue->item_to_link_map, file);
+
+	if (link == NULL) {
+		/* It's not on the queue */
+		return;
+	}
+
+	if (link == queue->tail) {
+		/* Need to special-case removing the tail. */
+		queue->tail = queue->tail->prev;
+	}
+
+	queue->head =  g_list_remove_link (queue->head, link);
+	g_list_free (link);
+	g_hash_table_remove (queue->item_to_link_map, file);
+
+	nautilus_file_unref (file);
+}
+
+NautilusFile *
+nautilus_file_queue_head (NautilusFileQueue *queue)
+{
+	if (queue->head == NULL) {
+		return NULL;
+	}
+
+	return NAUTILUS_FILE (queue->head->data);
+}
+
+gboolean
+nautilus_file_queue_is_empty (NautilusFileQueue *queue)
+{
+	return (queue->head == NULL);
+}