2 // Mono.Data.TdsClient.TdsConnectionPool.cs
5 // Lluis Sanchez Gual (lluis@ximian.com)
6 // Christian Hergert (christian.hergert@gmail.com)
7 // Gonzalo Paniagua Javier (gonzalo@novell.com)
9 // Copyright (C) 2004 Novell, Inc.
10 // Copyright (C) 2009 Novell, Inc.
13 // Permission is hereby granted, free of charge, to any person obtaining
14 // a copy of this software and associated documentation files (the
15 // "Software"), to deal in the Software without restriction, including
16 // without limitation the rights to use, copy, modify, merge, publish,
17 // distribute, sublicense, and/or sell copies of the Software, and to
18 // permit persons to whom the Software is furnished to do so, subject to
19 // the following conditions:
21 // The above copyright notice and this permission notice shall be
22 // included in all copies or substantial portions of the Software.
24 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
25 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
26 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
27 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
28 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
29 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
30 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
34 using System.Collections;
36 using System.Threading;
38 namespace Mono.Data.Tds.Protocol
40 public class TdsConnectionPoolManager
42 Hashtable pools = Hashtable.Synchronized (new Hashtable ());
45 public TdsConnectionPoolManager (TdsVersion version)
47 this.version = version;
50 public TdsConnectionPool GetConnectionPool (string connectionString, TdsConnectionInfo info)
52 TdsConnectionPool pool = (TdsConnectionPool) pools [connectionString];
54 pools [connectionString] = new TdsConnectionPool (this, info);
55 pool = (TdsConnectionPool) pools [connectionString];
60 public TdsConnectionPool GetConnectionPool (string connectionString)
62 return (TdsConnectionPool) pools [connectionString];
65 public virtual Tds CreateConnection (TdsConnectionInfo info)
67 //Console.WriteLine ("CreateConnection: TdsVersion:{0}", version);
70 case TdsVersion.tds42:
71 return new Tds42 (info.DataSource, info.Port, info.PacketSize, info.Timeout);
72 case TdsVersion.tds50:
73 return new Tds50 (info.DataSource, info.Port, info.PacketSize, info.Timeout);
74 case TdsVersion.tds70:
75 return new Tds70 (info.DataSource, info.Port, info.PacketSize, info.Timeout, info.LifeTime);
76 case TdsVersion.tds80:
77 return new Tds80 (info.DataSource, info.Port, info.PacketSize, info.Timeout, info.LifeTime);
79 throw new NotSupportedException ();
82 public IDictionary GetConnectionPool ()
88 public class TdsConnectionInfo
90 [Obsolete ("Use the constructor that receives a lifetime parameter")]
91 public TdsConnectionInfo (string dataSource, int port, int packetSize, int timeout, int minSize, int maxSize)
92 : this (dataSource, port, packetSize, timeout, minSize, maxSize, 0)
96 public TdsConnectionInfo (string dataSource, int port, int packetSize, int timeout, int minSize, int maxSize, int lifeTime)
98 DataSource = dataSource;
100 PacketSize = packetSize;
102 PoolMinSize = minSize;
103 PoolMaxSize = maxSize;
107 public string DataSource;
109 public int PacketSize;
112 public int PoolMinSize;
113 public int PoolMaxSize;
115 public override string ToString ()
117 StringBuilder sb = new StringBuilder ();
118 sb.AppendFormat ("DataSouce: {0}\n", DataSource);
119 sb.AppendFormat ("Port: {0}\n", Port);
120 sb.AppendFormat ("PacketSize: {0}\n", PacketSize);
121 sb.AppendFormat ("Timeout: {0}\n", Timeout);
122 sb.AppendFormat ("PoolMinSize: {0}\n", PoolMinSize);
123 sb.AppendFormat ("PoolMaxSize: {0}", PoolMaxSize);
124 return sb.ToString ();
128 public class TdsConnectionPool
130 TdsConnectionInfo info;
132 TdsConnectionPoolManager manager;
136 public TdsConnectionPool (TdsConnectionPoolManager manager, TdsConnectionInfo info)
139 this.manager = manager;
140 conns = new ArrayList (info.PoolMaxSize);
141 available = new Queue (info.PoolMaxSize);
145 void InitializePool ()
147 /* conns.Count might not be 0 when we are resetting the connection pool */
148 for (int i = conns.Count; i < info.PoolMinSize; i++) {
150 Tds t = manager.CreateConnection (info);
152 available.Enqueue (t);
154 // Ignore. GetConnection will throw again.
159 public bool Pooling {
160 get { return !no_pooling; }
161 set { no_pooling = !value; }
167 public Tds GetConnection ()
170 return manager.CreateConnection (info);
174 int retries = info.PoolMaxSize * 2;
176 while (result == null) {
179 if (available.Count > 0) {
180 result = (Tds) available.Dequeue ();
181 break; // .. and do the reset out of the loop
183 Monitor.Enter (conns);
185 if (conns.Count >= info.PoolMaxSize - in_progress) {
186 Monitor.Exit (conns);
187 bool got_lock = Monitor.Wait (available, info.Timeout * 1000);
189 throw new InvalidOperationException (
190 "Timeout expired. The timeout period elapsed before a " +
191 "connection could be obtained. A possible explanation " +
192 "is that all the connections in the pool are in use, " +
193 "and the maximum pool size is reached.");
194 } else if (available.Count > 0) {
195 result = (Tds) available.Dequeue ();
196 break; // .. and do the reset out of the loop
204 Monitor.Exit (conns); // Exiting if not owned is ok < 2.x
209 result = manager.CreateConnection (info);
220 bool remove_cnc = true;
221 Exception exc = null;
223 remove_cnc = (!result.IsConnected || !result.Reset ());
224 } catch (Exception e) {
230 conns.Remove (result);
231 result.Disconnect ();
241 public void ReleaseConnection (Tds connection)
243 if (connection == null)
246 connection.Disconnect ();
250 if (connection.poolStatus == 2 || connection.Expired) {
252 conns.Remove (connection);
253 connection.Disconnect ();
257 if (connection != null) // connection is still open
258 available.Enqueue (connection);
259 // We pulse even if we don't queue, because null means that there's a slot
260 // available in 'conns'
261 Monitor.Pulse (available);
266 public void ResetConnectionPool ()
272 for (i = conns.Count - 1; i >= 0; i--) {
273 tds = (Tds) conns [i];
274 tds.poolStatus = 2; // 2 -> disconnect me upon release
276 for (i = available.Count - 1; i >= 0; i--) {
277 tds = (Tds) available.Dequeue ();
284 Monitor.PulseAll (available);
288 #endregion // Methods