12 files changed, 767 insertions, 36 deletions

diff --git a/crypto/src/util/collections/CollectionUtilities.cs b/crypto/src/util/collections/CollectionUtilities.cs
index fd0bdcc7a..18fcb6774 100644
--- a/crypto/src/util/collections/CollectionUtilities.cs
+++ b/crypto/src/util/collections/CollectionUtilities.cs
@@ -4,13 +4,9 @@ using System.Text;
 
 namespace Org.BouncyCastle.Utilities.Collections
 {
-	public sealed class CollectionUtilities
-	{
-		private CollectionUtilities()
-		{
-		}
-
-        public static void AddRange(IList to, ICollection range)
+    public abstract class CollectionUtilities
+    {
+        public static void AddRange(IList to, IEnumerable range)
         {
             foreach (object o in range)
             {
@@ -18,17 +14,15 @@ namespace Org.BouncyCastle.Utilities.Collections
             }
         }
 
-        public static bool CheckElementsAreOfType(
-			IEnumerable e,
-			Type		t)
-		{
-			foreach (object o in e)
-			{
-				if (!t.IsInstanceOfType(o))
-					return false;
-			}
-			return true;
-		}
+        public static bool CheckElementsAreOfType(IEnumerable e, Type t)
+        {
+            foreach (object o in e)
+            {
+                if (!t.IsInstanceOfType(o))
+                    return false;
+            }
+            return true;
+        }
 
         public static IDictionary ReadOnly(IDictionary d)
         {
@@ -45,27 +39,26 @@ namespace Org.BouncyCastle.Utilities.Collections
             return new UnmodifiableSetProxy(s);
         }
 
-        public static string ToString(
-			IEnumerable c)
-		{
-			StringBuilder sb = new StringBuilder("[");
+        public static string ToString(IEnumerable c)
+        {
+            StringBuilder sb = new StringBuilder("[");
 
-			IEnumerator e = c.GetEnumerator();
+            IEnumerator e = c.GetEnumerator();
 
-			if (e.MoveNext())
-			{
-				sb.Append(e.Current.ToString());
+            if (e.MoveNext())
+            {
+                sb.Append(e.Current.ToString());
 
-				while (e.MoveNext())
-				{
-					sb.Append(", ");
-					sb.Append(e.Current.ToString());
-				}
-			}
+                while (e.MoveNext())
+                {
+                    sb.Append(", ");
+                    sb.Append(e.Current.ToString());
+                }
+            }
 
-			sb.Append(']');
+            sb.Append(']');
 
-			return sb.ToString();
-		}
-	}
+            return sb.ToString();
+        }
+    }
 }
diff --git a/crypto/src/util/collections/EmptyEnumerable.cs b/crypto/src/util/collections/EmptyEnumerable.cs
new file mode 100644
index 000000000..a61a0789a
--- /dev/null
+++ b/crypto/src/util/collections/EmptyEnumerable.cs
@@ -0,0 +1,44 @@
+using System;
+using System.Collections;
+
+namespace Org.BouncyCastle.Utilities.Collections
+{
+	public sealed class EmptyEnumerable
+		: IEnumerable
+	{
+		public static readonly IEnumerable Instance = new EmptyEnumerable();
+
+		private EmptyEnumerable()
+		{
+		}
+
+		public IEnumerator GetEnumerator()
+		{
+			return EmptyEnumerator.Instance;
+		}
+	}
+
+	public sealed class EmptyEnumerator
+		: IEnumerator
+	{
+		public static readonly IEnumerator Instance = new EmptyEnumerator();
+
+		private EmptyEnumerator()
+		{
+		}
+
+		public bool MoveNext()
+		{
+			return false;
+		}
+
+		public void Reset()
+		{
+		}
+
+		public object Current
+		{
+			get { throw new InvalidOperationException("No elements"); }
+		}
+	}
+}
diff --git a/crypto/src/util/collections/EnumerableProxy.cs b/crypto/src/util/collections/EnumerableProxy.cs
new file mode 100644
index 000000000..9eec4af21
--- /dev/null
+++ b/crypto/src/util/collections/EnumerableProxy.cs
@@ -0,0 +1,25 @@
+using System;
+using System.Collections;
+
+namespace Org.BouncyCastle.Utilities.Collections
+{
+	public sealed class EnumerableProxy
+		: IEnumerable
+	{
+		private readonly IEnumerable inner;
+
+		public EnumerableProxy(
+			IEnumerable inner)
+		{
+			if (inner == null)
+				throw new ArgumentNullException("inner");
+
+			this.inner = inner;
+		}
+
+		public IEnumerator GetEnumerator()
+		{
+			return inner.GetEnumerator();
+		}
+	}
+}
diff --git a/crypto/src/util/collections/HashSet.cs b/crypto/src/util/collections/HashSet.cs
new file mode 100644
index 000000000..1facb58e3
--- /dev/null
+++ b/crypto/src/util/collections/HashSet.cs
@@ -0,0 +1,99 @@
+using System;
+using System.Collections;
+
+namespace Org.BouncyCastle.Utilities.Collections
+{
+	public class HashSet
+		: ISet
+	{
+		private readonly IDictionary impl = Platform.CreateHashtable();
+
+		public HashSet()
+		{
+		}
+
+		public HashSet(IEnumerable s)
+		{
+			foreach (object o in s)
+			{
+				Add(o);
+			}
+		}
+
+		public virtual void Add(object o)
+		{
+			impl[o] = null;
+		}
+
+		public virtual void AddAll(IEnumerable e)
+		{
+			foreach (object o in e)
+			{
+				Add(o);
+			}
+		}
+
+		public virtual void Clear()
+		{
+			impl.Clear();
+		}
+
+		public virtual bool Contains(object o)
+		{
+			return impl.Contains(o);
+		}
+
+		public virtual void CopyTo(Array array, int index)
+		{
+			impl.Keys.CopyTo(array, index);
+		}
+
+		public virtual int Count
+		{
+			get { return impl.Count; }
+		}
+
+		public virtual IEnumerator GetEnumerator()
+		{
+			return impl.Keys.GetEnumerator();
+		}
+
+		public virtual bool IsEmpty
+		{
+			get { return impl.Count == 0; }
+		}
+
+		public virtual bool IsFixedSize
+		{
+			get { return impl.IsFixedSize; }
+		}
+
+		public virtual bool IsReadOnly
+		{
+			get { return impl.IsReadOnly; }
+		}
+
+		public virtual bool IsSynchronized
+		{
+			get { return impl.IsSynchronized; }
+		}
+
+		public virtual void Remove(object o)
+		{
+			impl.Remove(o);
+		}
+
+		public virtual void RemoveAll(IEnumerable e)
+		{
+			foreach (object o in e)
+			{
+				Remove(o);
+			}
+		}
+
+		public virtual object SyncRoot
+		{
+			get { return impl.SyncRoot; }
+		}
+	}
+}
diff --git a/crypto/src/util/collections/ISet.cs b/crypto/src/util/collections/ISet.cs
new file mode 100644
index 000000000..1f8edba40
--- /dev/null
+++ b/crypto/src/util/collections/ISet.cs
@@ -0,0 +1,19 @@
+using System;
+using System.Collections;
+
+namespace Org.BouncyCastle.Utilities.Collections
+{
+	public interface ISet
+		: ICollection
+	{
+		void Add(object o);
+		void AddAll(IEnumerable e);
+		void Clear();
+		bool Contains(object o);
+		bool IsEmpty { get; }
+		bool IsFixedSize { get; }
+		bool IsReadOnly { get; }
+		void Remove(object o);
+		void RemoveAll(IEnumerable e);
+	}
+}
diff --git a/crypto/src/util/collections/LinkedDictionary.cs b/crypto/src/util/collections/LinkedDictionary.cs
new file mode 100644
index 000000000..933d38ded
--- /dev/null
+++ b/crypto/src/util/collections/LinkedDictionary.cs
@@ -0,0 +1,178 @@
+using System;
+using System.Collections;
+
+namespace Org.BouncyCastle.Utilities.Collections
+{
+	public class LinkedDictionary
+		: IDictionary
+	{
+		internal readonly IDictionary hash = Platform.CreateHashtable();
+		internal readonly IList keys = Platform.CreateArrayList();
+
+		public LinkedDictionary()
+		{
+		}
+
+		public virtual void Add(object k, object v)
+		{
+			hash.Add(k, v);
+			keys.Add(k);
+		}
+
+		public virtual void Clear()
+		{
+			hash.Clear();
+			keys.Clear();
+		}
+
+		public virtual bool Contains(object k)
+		{
+			return hash.Contains(k);
+		}
+
+		public virtual void CopyTo(Array array, int index)
+		{
+			foreach (object k in keys)
+			{
+				array.SetValue(hash[k], index++);
+			}
+		}
+
+		public virtual int Count
+		{
+			get { return hash.Count; }
+		}
+
+		IEnumerator IEnumerable.GetEnumerator()
+		{
+			return GetEnumerator();
+		}
+
+		public virtual IDictionaryEnumerator GetEnumerator()
+		{
+			return new LinkedDictionaryEnumerator(this);
+		}
+
+		public virtual void Remove(object k)
+		{
+			hash.Remove(k);
+			keys.Remove(k);
+		}
+
+		public virtual bool IsFixedSize
+		{
+			get { return false; }
+		}
+
+		public virtual bool IsReadOnly
+		{
+			get { return false; }
+		}
+
+		public virtual bool IsSynchronized
+		{
+			get { return false; }
+		}
+
+		public virtual object SyncRoot
+		{
+			get { return false; }
+		}
+
+		public virtual ICollection Keys
+		{
+            get { return Platform.CreateArrayList(keys); }
+		}
+
+		public virtual ICollection Values
+		{
+			// NB: Order has to be the same as for Keys property
+			get
+			{
+                IList values = Platform.CreateArrayList(keys.Count);
+				foreach (object k in keys)
+				{
+					values.Add(hash[k]);
+				}
+				return values;
+			}
+		}
+
+		public virtual object this[object k]
+		{
+			get
+			{
+				return hash[k];
+			}
+			set
+			{
+				if (!hash.Contains(k))
+					keys.Add(k);
+				hash[k] = value;
+			}
+		}
+	}
+
+	internal class LinkedDictionaryEnumerator : IDictionaryEnumerator
+	{
+		private readonly LinkedDictionary parent;
+		private int pos = -1;
+
+		internal LinkedDictionaryEnumerator(LinkedDictionary parent)
+		{
+			this.parent = parent;
+		}
+
+		public virtual object Current
+		{
+			get { return Entry; }
+		}
+
+		public virtual DictionaryEntry Entry
+		{
+			get
+			{
+				object k = CurrentKey;
+				return new DictionaryEntry(k, parent.hash[k]);
+			}
+		}
+
+		public virtual object Key
+		{
+			get
+			{
+				return CurrentKey;
+			}
+		}
+
+		public virtual bool MoveNext()
+		{
+			if (pos >= parent.keys.Count)
+				return false;
+			return ++pos < parent.keys.Count;
+		}
+
+		public virtual void Reset()
+		{
+			this.pos = -1;
+		}
+
+		public virtual object Value
+		{
+			get
+			{
+				return parent.hash[CurrentKey];
+			}
+		}
+
+		private object CurrentKey
+		{
+			get
+			{
+				if (pos < 0 || pos >= parent.keys.Count)
+					throw new InvalidOperationException();
+				return parent.keys[pos];
+			}
+		}
+	}
+}
diff --git a/crypto/src/util/collections/UnmodifiableDictionary.cs b/crypto/src/util/collections/UnmodifiableDictionary.cs
new file mode 100644
index 000000000..0bdf70ad7
--- /dev/null
+++ b/crypto/src/util/collections/UnmodifiableDictionary.cs
@@ -0,0 +1,64 @@
+using System;
+using System.Collections;
+
+namespace Org.BouncyCastle.Utilities.Collections
+{
+	public abstract class UnmodifiableDictionary
+		: IDictionary
+	{
+		protected UnmodifiableDictionary()
+		{
+		}
+
+		public virtual void Add(object k, object v)
+		{
+			throw new NotSupportedException();
+		}
+
+		public virtual void Clear()
+		{
+			throw new NotSupportedException();
+		}
+
+		public abstract bool Contains(object k);
+
+		public abstract void CopyTo(Array array, int index);
+
+		public abstract int Count { get; }
+
+		IEnumerator IEnumerable.GetEnumerator()
+		{
+			return GetEnumerator();
+		}
+
+		public abstract IDictionaryEnumerator GetEnumerator();
+
+		public virtual void Remove(object k)
+		{
+			throw new NotSupportedException();
+		}
+
+		public abstract bool IsFixedSize { get; }
+
+		public virtual bool IsReadOnly
+		{
+			get { return true; }
+		}
+
+		public abstract bool IsSynchronized { get; }
+
+		public abstract object SyncRoot { get; }
+
+		public abstract ICollection Keys { get; }
+
+		public abstract ICollection Values { get; }
+
+		public virtual object this[object k]
+		{
+			get { return GetValue(k); }
+			set { throw new NotSupportedException(); }
+		}
+
+		protected abstract object GetValue(object k);
+	}
+}
diff --git a/crypto/src/util/collections/UnmodifiableDictionaryProxy.cs b/crypto/src/util/collections/UnmodifiableDictionaryProxy.cs
new file mode 100644
index 000000000..0fca909a3
--- /dev/null
+++ b/crypto/src/util/collections/UnmodifiableDictionaryProxy.cs
@@ -0,0 +1,66 @@
+using System;
+using System.Collections;
+
+namespace Org.BouncyCastle.Utilities.Collections
+{
+	public class UnmodifiableDictionaryProxy
+		: UnmodifiableDictionary
+	{
+		private readonly IDictionary d;
+
+		public UnmodifiableDictionaryProxy(IDictionary d)
+		{
+			this.d = d;
+		}
+
+		public override bool Contains(object k)
+		{
+			return d.Contains(k);
+		}
+
+		public override void CopyTo(Array array, int index)
+		{
+			d.CopyTo(array, index);
+		}
+
+		public override int Count
+		{
+			get { return d.Count; }
+		}
+
+		public override IDictionaryEnumerator GetEnumerator()
+		{
+			return d.GetEnumerator();
+		}
+
+		public override bool IsFixedSize
+		{
+			get { return d.IsFixedSize; }
+		}
+
+		public override bool IsSynchronized
+		{
+			get { return d.IsSynchronized; }
+		}
+
+		public override object SyncRoot
+		{
+			get { return d.SyncRoot; }
+		}
+
+		public override ICollection Keys
+		{
+			get { return d.Keys; }
+		}
+
+		public override ICollection Values
+		{
+			get { return d.Values; }
+		}
+
+		protected override object GetValue(object k)
+		{
+			return d[k];
+		}
+	}
+}
diff --git a/crypto/src/util/collections/UnmodifiableList.cs b/crypto/src/util/collections/UnmodifiableList.cs
new file mode 100644
index 000000000..28e49eac3
--- /dev/null
+++ b/crypto/src/util/collections/UnmodifiableList.cs
@@ -0,0 +1,67 @@
+using System;
+using System.Collections;
+
+namespace Org.BouncyCastle.Utilities.Collections
+{
+	public abstract class UnmodifiableList
+		: IList
+	{
+		protected UnmodifiableList()
+		{
+		}
+
+		public virtual int Add(object o)
+		{
+			throw new NotSupportedException();
+		}
+
+		public virtual void Clear()
+		{
+			throw new NotSupportedException();
+		}
+
+		public abstract bool Contains(object o);
+
+		public abstract void CopyTo(Array array, int index);
+
+		public abstract int Count { get; }
+
+		public abstract IEnumerator GetEnumerator();
+
+		public abstract int IndexOf(object o);
+
+		public virtual void Insert(int i, object o)
+		{
+			throw new NotSupportedException();
+		}
+
+		public abstract bool IsFixedSize { get; }
+
+		public virtual bool IsReadOnly
+		{
+			get { return true; }
+		}
+
+		public abstract bool IsSynchronized { get; }
+
+		public virtual void Remove(object o)
+		{
+			throw new NotSupportedException();
+		}
+
+		public virtual void RemoveAt(int i)
+		{
+			throw new NotSupportedException();
+		}
+
+		public abstract object SyncRoot { get; }
+		
+		public virtual object this[int i]
+		{
+			get { return GetValue(i); }
+			set { throw new NotSupportedException(); }
+		}
+
+		protected abstract object GetValue(int i);
+	}
+}
diff --git a/crypto/src/util/collections/UnmodifiableListProxy.cs b/crypto/src/util/collections/UnmodifiableListProxy.cs
new file mode 100644
index 000000000..9d00737ef
--- /dev/null
+++ b/crypto/src/util/collections/UnmodifiableListProxy.cs
@@ -0,0 +1,61 @@
+using System;
+using System.Collections;
+
+namespace Org.BouncyCastle.Utilities.Collections
+{
+	public class UnmodifiableListProxy
+		: UnmodifiableList
+	{
+		private readonly IList l;
+
+		public UnmodifiableListProxy(IList l)
+		{
+			this.l = l;
+		}
+
+		public override bool Contains(object o)
+		{
+			return l.Contains(o);
+		}
+
+		public override void CopyTo(Array array, int index)
+		{
+			l.CopyTo(array, index);
+		}
+
+		public override int Count
+		{
+			get { return l.Count; }
+		}
+
+		public override IEnumerator GetEnumerator()
+		{
+			return l.GetEnumerator();
+		}
+
+		public override int IndexOf(object o)
+		{
+			return l.IndexOf(o);
+		}
+
+		public override bool IsFixedSize
+		{
+			get { return l.IsFixedSize; }
+		}
+
+		public override bool IsSynchronized
+		{
+			get { return l.IsSynchronized; }
+		}
+
+		public override object SyncRoot
+		{
+			get { return l.SyncRoot; }
+		}
+
+		protected override object GetValue(int i)
+		{
+			return l[i];
+		}
+	}
+}
diff --git a/crypto/src/util/collections/UnmodifiableSet.cs b/crypto/src/util/collections/UnmodifiableSet.cs
new file mode 100644
index 000000000..8792815ac
--- /dev/null
+++ b/crypto/src/util/collections/UnmodifiableSet.cs
@@ -0,0 +1,59 @@
+using System;
+using System.Collections;
+
+namespace Org.BouncyCastle.Utilities.Collections
+{
+	public abstract class UnmodifiableSet
+		: ISet
+	{
+		protected UnmodifiableSet()
+		{
+		}
+
+		public virtual void Add(object o)
+		{
+			throw new NotSupportedException();
+		}
+
+		public virtual void AddAll(IEnumerable e)
+		{
+			throw new NotSupportedException();
+		}
+
+		public virtual void Clear()
+		{
+			throw new NotSupportedException();
+		}
+		
+		public abstract bool Contains(object o);
+
+		public abstract void CopyTo(Array array, int index);
+
+		public abstract int Count { get; }
+
+		public abstract IEnumerator GetEnumerator();
+
+		public abstract bool IsEmpty { get; }
+
+		public abstract bool IsFixedSize { get; }
+
+		public virtual bool IsReadOnly
+		{
+			get { return true; }
+		}
+
+		public abstract bool IsSynchronized { get; }
+
+		public abstract object SyncRoot { get; }
+
+		public virtual void Remove(object o)
+		{
+			throw new NotSupportedException();
+		}
+
+		public virtual void RemoveAll(IEnumerable e)
+		{
+			throw new NotSupportedException();
+		}
+	}
+}
diff --git a/crypto/src/util/collections/UnmodifiableSetProxy.cs b/crypto/src/util/collections/UnmodifiableSetProxy.cs
new file mode 100644
index 000000000..e119e2957
--- /dev/null
+++ b/crypto/src/util/collections/UnmodifiableSetProxy.cs
@@ -0,0 +1,56 @@
+using System;
+using System.Collections;
+
+namespace Org.BouncyCastle.Utilities.Collections
+{
+	public class UnmodifiableSetProxy
+		: UnmodifiableSet
+	{
+		private readonly ISet s;
+
+		public UnmodifiableSetProxy (ISet s)
+		{
+			this.s = s;
+		}
+
+		public override bool Contains(object o)
+		{
+			return s.Contains(o);
+		}
+
+		public override void CopyTo(Array array, int index)
+		{
+			s.CopyTo(array, index);
+		}
+
+		public override int Count
+		{
+			get { return s.Count; }
+		}
+
+		public override IEnumerator GetEnumerator()
+		{
+			return s.GetEnumerator();
+		}
+
+		public override bool IsEmpty
+		{
+			get { return s.IsEmpty; }
+		}
+
+		public override bool IsFixedSize
+		{
+			get { return s.IsFixedSize; }
+		}
+
+		public override bool IsSynchronized
+		{
+			get { return s.IsSynchronized; }
+		}
+
+		public override object SyncRoot
+		{
+			get { return s.SyncRoot; }
+		}
+	}
+}