(DISTFILES): Comment out a few missing files.

[mono-project.git] / mcs / class / corlib / System.Collections.Generic / Queue.cs

// -*- Mode: csharp; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
//
// System.Collections.Generic.Queue
//
// Author:
//    Martin Baulig (martin@ximian.com)
//
// (C) 2003 Novell, Inc.
//

//
// Copyright (C) 2004 Novell, Inc (http://www.novell.com)
//
// Permission is hereby granted, free of charge, to any person obtaining
// a copy of this software and associated documentation files (the
// "Software"), to deal in the Software without restriction, including
// without limitation the rights to use, copy, modify, merge, publish,
// distribute, sublicense, and/or sell copies of the Software, and to
// permit persons to whom the Software is furnished to do so, subject to
// the following conditions:
// 
// The above copyright notice and this permission notice shall be
// included in all copies or substantial portions of the Software.
// 
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
// LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
// OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
// WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
//

#if NET_2_0
using System;
using System.Runtime.InteropServices;

namespace System.Collections.Generic
{
        [CLSCompliant(false)]
        [ComVisible(false)]
        public class Queue<T> : ICollection<T>, IEnumerable<T>,
                ICollection, IEnumerable
        {
                int count;
                protected int modified;
                protected Node head;
                Node tail;

                public void Clear ()
                {
                        head = tail = null;
                        count = 0;
                        modified++;
                }

                public void Enqueue (T item)
                {
                        tail = new Node (tail, item);
                        if (head == null)
                                head = tail;
                        count++;
                        modified++;
                }

                public T Peek ()
                {
                        if (head == null)
                                throw new ArgumentException ();

                        return head.Item;
                }

                public T Dequeue ()
                {
                        if (head == null)
                                throw new ArgumentException ();

                        T retval = head.Item;
                        head = head.Next;
                        if (head == null)
                                tail = null;
                        count--;
                        modified++;
                        return retval;
                }

                public bool Contains (T item)
                {
                        for (Node node = head; node != null; node = node.Next)
                                if (node.Item == item)
                                        return true;

                        return false;
                }

                public virtual void CopyTo (T[] array, int start)
                {
                        // re-ordered to avoid possible integer overflow
                        if (start >= array.Length - count)
                                throw new ArgumentException ();

                        for (Node node = head; node != null; node = node.Next)
                                array [start++] = node.Item;
                }

                void ICollection.CopyTo (Array array, int start)
                {
                        // re-ordered to avoid possible integer overflow
                        if (start >= array.Length - count)
                                throw new ArgumentException ();

                        for (Node node = head; node != null; node = node.Next)
                                array.SetValue (node.Item, start++);
                }

                public T[] ToArray ()
                {
                        int pos = 0;
                        T[] retval = new T [count];
                        for (Node node = head; node != null; node = node.Next)
                                retval [pos++] = node.Item;

                        return retval;
                }

                public void TrimToSize ()
                { }

                public int Count {
                        get { return count; }
                }

                public bool IsSynchronized {
                        get { return false; }
                }

                public object SyncRoot {
                        get { return this; }
                }

                public bool IsReadOnly {
                        get { return false; }
                }

                public void Add (T item)
                {
                        Enqueue (item);
                }

                public bool Remove (T item)
                {
                        throw new NotImplementedException ();
                }

                public IEnumerator<T> GetEnumerator ()
                {
                        return new Enumerator (this);
                }

                IEnumerator IEnumerable.GetEnumerator ()
                {
                        return new Enumerator (this);
                }

                protected sealed class Node
                {
                        public readonly T Item;
                        public readonly Node Next;

                        public Node (Node next, T item)
                        {
                                this.Next = next;
                                this.Item = item;
                        }
                }

                protected class Enumerator : IEnumerator<T>, IEnumerator
                {
                        Queue<T> queue;
                        int modified;
                        Node current;

                        public Enumerator (Queue<T> queue)
                        {
                                this.queue = queue;
                                this.modified = queue.modified;
                                this.current = queue.head;
                        }

                        public T Current {
                                get {
                                        if (queue.modified != modified)
                                                throw new InvalidOperationException ();
                                        if (current == null)
                                                throw new ArgumentException ();
                                        return current.Item;
                                }
                        }

                        object IEnumerator.Current {
                                get {
                                        return Current;
                                }
                        }

                        public bool MoveNext ()
                        {
                                if (queue.modified != modified)
                                        throw new InvalidOperationException ();
                                if (current == null)
                                        throw new ArgumentException ();

                                current = current.Next;
                                return current != null;
                        }

                        public void Reset () {
                                if (queue.modified != modified)
                                        throw new InvalidOperationException();

                                current = queue.head;
                        }

                        public void Dispose ()
                        {
                                modified = -1;
                        }
                }
        }
}
#endif