mcs/class/System/System.Threading/Semaphore.cs

   1 //
   2 // System.Threading.Semaphore.cs
   3 //
   4 // Author:
   5 //      Sebastien Pouliot  <sebastien@ximian.com>
   6 //
   7 // Copyright (C) 2005 Novell, Inc (http://www.novell.com)
   8 //
   9 // Permission is hereby granted, free of charge, to any person obtaining
  10 // a copy of this software and associated documentation files (the
  11 // "Software"), to deal in the Software without restriction, including
  12 // without limitation the rights to use, copy, modify, merge, publish,
  13 // distribute, sublicense, and/or sell copies of the Software, and to
  14 // permit persons to whom the Software is furnished to do so, subject to
  15 // the following conditions:
  16 //
  17 // The above copyright notice and this permission notice shall be
  18 // included in all copies or substantial portions of the Software.
  19 //
  20 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  21 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  22 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  23 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  24 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  25 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  26 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  27 //
  28
  29 #if NET_2_0
  30
  31 using System.Runtime.ConstrainedExecution;
  32 using System.Runtime.InteropServices;
  33 using System.Security.AccessControl;
  34 using System.Runtime.CompilerServices;
  35 using System.IO;
  36
  37 namespace System.Threading {
  38
  39         [ComVisible (false)]
  40         public sealed class Semaphore : WaitHandle {
  41
  42 #if !TARGET_JVM
  43                 [MethodImplAttribute(MethodImplOptions.InternalCall)]
  44                 private static extern IntPtr CreateSemaphore_internal (
  45                         int initialCount, int maximumCount, string name,
  46                         out bool createdNew);
  47
  48                 [MethodImplAttribute(MethodImplOptions.InternalCall)]
  49                 private static extern int ReleaseSemaphore_internal (
  50                         IntPtr handle, int releaseCount, out bool fail);
  51
  52                 [MethodImplAttribute (MethodImplOptions.InternalCall)]
  53                 private static extern IntPtr OpenSemaphore_internal (string name, SemaphoreRights rights, out MonoIOError error);
  54 #endif
  55
  56                 private Semaphore (IntPtr handle)
  57                 {
  58                         Handle = handle;
  59                 }
  60
  61                 public Semaphore (int initialCount, int maximumCount)
  62                         : this (initialCount, maximumCount, null)
  63                 {
  64                 }
  65
  66                 public Semaphore (int initialCount, int maximumCount, string name)
  67                 {
  68                         if (initialCount < 0)
  69                                 throw new ArgumentOutOfRangeException ("initialCount", "< 0");
  70                         if (maximumCount < 1)
  71                                 throw new ArgumentOutOfRangeException ("maximumCount", "< 1");
  72                         if (initialCount > maximumCount)
  73                                 throw new ArgumentException ("initialCount > maximumCount");
  74
  75                         bool created;
  76
  77                         Handle = CreateSemaphore_internal (initialCount,
  78                                                            maximumCount, name,
  79                                                            out created);
  80                 }
  81
  82                 public Semaphore (int initialCount, int maximumCount, string name, out bool createdNew)
  83                         : this (initialCount, maximumCount, name, out createdNew, null)
  84                 {
  85                 }
  86
  87                 [MonoTODO ("Does not support access control, semaphoreSecurity is ignored")]
  88                 public Semaphore (int initialCount, int maximumCount, string name, out bool createdNew,
  89                         SemaphoreSecurity semaphoreSecurity)
  90                 {
  91                         if (initialCount < 0)
  92                                 throw new ArgumentOutOfRangeException ("initialCount", "< 0");
  93                         if (maximumCount < 1)
  94                                 throw new ArgumentOutOfRangeException ("maximumCount", "< 1");
  95                         if (initialCount > maximumCount)
  96                                 throw new ArgumentException ("initialCount > maximumCount");
  97
  98                         Handle = CreateSemaphore_internal (initialCount,
  99                                                            maximumCount, name,
 100                                                            out createdNew);
 101                 }
 102
 103                 [MonoTODO]
 104                 public SemaphoreSecurity GetAccessControl ()
 105                 {
 106                         throw new NotImplementedException ();
 107                 }
 108
 109                 [PrePrepareMethod]
 110                 [ReliabilityContract (Consistency.WillNotCorruptState, Cer.Success)]
 111                 public int Release ()
 112                 {
 113                         return (Release (1));
 114                 }
 115
 116                 [ReliabilityContract (Consistency.WillNotCorruptState, Cer.Success)]
 117                 public int Release (int releaseCount)
 118                 {
 119 #if TARGET_JVM
 120                         throw new NotImplementedException ();
 121 #else
 122                         if (releaseCount < 1)
 123                                 throw new ArgumentOutOfRangeException ("releaseCount");
 124
 125                         int ret;
 126                         bool fail;
 127
 128                         ret = ReleaseSemaphore_internal (Handle, releaseCount,
 129                                                          out fail);
 130
 131                         if (fail) {
 132                                 throw new SemaphoreFullException ();
 133                         }
 134
 135                         return (ret);
 136 #endif
 137                 }
 138
 139                 [MonoTODO]
 140                 public void SetAccessControl (SemaphoreSecurity semaphoreSecurity)
 141                 {
 142                         if (semaphoreSecurity == null)
 143                                 throw new ArgumentNullException ("semaphoreSecurity");
 144
 145                         throw new NotImplementedException ();
 146                 }
 147
 148                 // static methods
 149
 150                 public static Semaphore OpenExisting (string name)
 151                 {
 152                         return OpenExisting (name, SemaphoreRights.Synchronize | SemaphoreRights.Modify);
 153                 }
 154
 155                 public static Semaphore OpenExisting (string name, SemaphoreRights rights)
 156                 {
 157                         if (name == null)
 158                                 throw new ArgumentNullException ("name");
 159                         if ((name.Length ==0) || (name.Length > 260))
 160                                 throw new ArgumentException ("name", Locale.GetText ("Invalid length [1-260]."));
 161
 162 #if !TARGET_JVM
 163                         MonoIOError error;
 164                         IntPtr handle = OpenSemaphore_internal (name, rights,
 165                                                                 out error);
 166                         if (handle == (IntPtr)null) {
 167                                 if (error == MonoIOError.ERROR_FILE_NOT_FOUND) {
 168                                         throw new WaitHandleCannotBeOpenedException (Locale.GetText ("Named Semaphore handle does not exist: ") + name);
 169                                 } else if (error == MonoIOError.ERROR_ACCESS_DENIED) {
 170                                         throw new UnauthorizedAccessException ();
 171                                 } else {
 172                                         throw new IOException (Locale.GetText ("Win32 IO error: ") + error.ToString ());
 173                                 }
 174                         }
 175
 176                         return(new Semaphore (handle));
 177 #else
 178                         return null;
 179 #endif
 180                 }
 181         }
 182 }
 183
 184 #endif