mcs/class/corlib/System.Threading/Mutex.cs

   1 //
   2 // System.Threading.Mutex.cs
   3 //
   4 // Author:
   5 //   Dick Porter (dick@ximian.com)
   6 //   Veronica De Santis (veron78@interfree.it)
   7 //
   8 // (C) Ximian, Inc.  http://www.ximian.com
   9 // Copyright (C) 2004-2005 Novell, Inc (http://www.novell.com)
  10 //
  11 // Permission is hereby granted, free of charge, to any person obtaining
  12 // a copy of this software and associated documentation files (the
  13 // "Software"), to deal in the Software without restriction, including
  14 // without limitation the rights to use, copy, modify, merge, publish,
  15 // distribute, sublicense, and/or sell copies of the Software, and to
  16 // permit persons to whom the Software is furnished to do so, subject to
  17 // the following conditions:
  18 //
  19 // The above copyright notice and this permission notice shall be
  20 // included in all copies or substantial portions of the Software.
  21 //
  22 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  23 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  24 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  25 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  26 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  27 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  28 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  29 //
  30
  31 using System.Runtime.CompilerServices;
  32 using System.Security.Permissions;
  33
  34 using System.Runtime.ConstrainedExecution;
  35 using System.IO;
  36 using System.Runtime.InteropServices;
  37 using System.Security.AccessControl;
  38
  39 namespace System.Threading
  40 {
  41         [ComVisible (true)]
  42         public sealed class Mutex : WaitHandle
  43         {
  44                 [MethodImplAttribute(MethodImplOptions.InternalCall)]
  45                 private unsafe static extern IntPtr CreateMutex_icall (bool initiallyOwned, char *name,
  46                         int name_length, out bool created);
  47
  48                 [MethodImplAttribute(MethodImplOptions.InternalCall)]
  49                 private unsafe static extern IntPtr OpenMutex_icall (char *name, int name_length,
  50                         MutexRights rights, out MonoIOError error);
  51
  52                 [MethodImplAttribute(MethodImplOptions.InternalCall)]
  53                 private static extern bool ReleaseMutex_internal(IntPtr handle);
  54
  55                 private unsafe static IntPtr CreateMutex_internal (bool initiallyOwned,
  56                         string name, out bool created)
  57                 {
  58                         fixed (char *fixed_name = name)
  59                                 return CreateMutex_icall (initiallyOwned, fixed_name,
  60                                         name?.Length ?? 0, out created);
  61                 }
  62
  63                 private unsafe static IntPtr OpenMutex_internal (string name, MutexRights rights, out MonoIOError error)
  64                 {
  65                         fixed (char *fixed_name = name)
  66                                 return OpenMutex_icall (fixed_name, name?.Length ?? 0, rights, out error);
  67                 }
  68
  69                 private Mutex (IntPtr handle)
  70                 {
  71                         Handle = handle;
  72                 }
  73
  74                 [ReliabilityContractAttribute (Consistency.WillNotCorruptState, Cer.MayFail)]
  75                 public Mutex() {
  76                         bool created;
  77
  78                         Handle=CreateMutex_internal(false, null, out created);
  79                 }
  80
  81                 [ReliabilityContractAttribute (Consistency.WillNotCorruptState, Cer.MayFail)]
  82                 public Mutex(bool initiallyOwned) {
  83                         bool created;
  84
  85                         Handle=CreateMutex_internal(initiallyOwned, null,
  86                                                     out created);
  87                 }
  88
  89 #if !MOBILE
  90                 [ReliabilityContractAttribute (Consistency.WillNotCorruptState, Cer.MayFail)]
  91                 [SecurityPermission (SecurityAction.LinkDemand, UnmanagedCode = true)]
  92                 public Mutex (bool initiallyOwned, string name)
  93                 {
  94                         bool created;
  95                         Handle = CreateMutex_internal (initiallyOwned, name, out created);
  96                 }
  97
  98                 [ReliabilityContractAttribute (Consistency.WillNotCorruptState, Cer.MayFail)]
  99                 [SecurityPermission (SecurityAction.LinkDemand, UnmanagedCode = true)]
 100                 public Mutex (bool initiallyOwned, string name, out bool createdNew)
 101                 {
 102                         Handle = CreateMutex_internal (initiallyOwned, name, out createdNew);
 103                 }
 104
 105                 [MonoTODO ("Use MutexSecurity in CreateMutex_internal")]
 106                 [ReliabilityContractAttribute (Consistency.WillNotCorruptState, Cer.MayFail)]
 107                 public Mutex (bool initiallyOwned, string name, out bool createdNew, MutexSecurity mutexSecurity)
 108                 {
 109                         Handle = CreateMutex_internal (initiallyOwned, name, out createdNew);
 110                 }
 111
 112                 public MutexSecurity GetAccessControl ()
 113                 {
 114                         return new MutexSecurity (SafeWaitHandle,
 115                                                   AccessControlSections.Owner |
 116                                                   AccessControlSections.Group |
 117                                                   AccessControlSections.Access);
 118                 }
 119
 120                 public static Mutex OpenExisting (string name)
 121                 {
 122                         return(OpenExisting (name, MutexRights.Synchronize |
 123                                              MutexRights.Modify));
 124                 }
 125
 126                 public static Mutex OpenExisting (string name,
 127                                                   MutexRights rights)
 128                 {
 129                         if (name == null) {
 130                                 throw new ArgumentNullException ("name");
 131                         }
 132                         if ((name.Length == 0) ||
 133                             (name.Length > 260)) {
 134                                 throw new ArgumentException ("name", Locale.GetText ("Invalid length [1-260]."));
 135                         }
 136
 137                         MonoIOError error;
 138                         IntPtr handle = OpenMutex_internal (name, rights,
 139                                                             out error);
 140                         if (handle == (IntPtr)null) {
 141                                 if (error == MonoIOError.ERROR_FILE_NOT_FOUND) {
 142                                         throw new WaitHandleCannotBeOpenedException (Locale.GetText ("Named Mutex handle does not exist: ") + name);
 143                                 } else if (error == MonoIOError.ERROR_ACCESS_DENIED) {
 144                                         throw new UnauthorizedAccessException ();
 145                                 } else {
 146                                         throw new IOException (Locale.GetText ("Win32 IO error: ") +  error.ToString ());
 147                                 }
 148                         }
 149
 150                         return(new Mutex (handle));
 151                 }
 152
 153                 public static bool TryOpenExisting (string name, out Mutex result)
 154                 {
 155                         return TryOpenExisting (name, MutexRights.Synchronize | MutexRights.Modify, out result);
 156                 }
 157
 158                 public static bool TryOpenExisting (string name, MutexRights rights, out Mutex result)
 159                 {
 160                         if (name == null) {
 161                                 throw new ArgumentNullException ("name");
 162                         }
 163                         if ((name.Length == 0) || (name.Length > 260)) {
 164                                 throw new ArgumentException ("name", Locale.GetText ("Invalid length [1-260]."));
 165                         }
 166
 167                         MonoIOError error;
 168                         IntPtr handle = OpenMutex_internal (name, rights, out error);
 169                         if (handle == (IntPtr)null) {
 170                                 result = null;
 171                                 return false;
 172                         }
 173
 174                         result = new Mutex (handle);
 175                         return true;
 176                 }
 177 #else
 178                 public Mutex (bool initiallyOwned, string name)
 179                 {
 180                         throw new NotSupportedException ();
 181                 }
 182
 183                 public Mutex (bool initiallyOwned, string name, out bool createdNew)
 184                 {
 185                         throw new NotSupportedException ();
 186                 }
 187
 188                 public Mutex (bool initiallyOwned, string name, out bool createdNew, MutexSecurity mutexSecurity)
 189                 {
 190                         throw new NotSupportedException ();
 191                 }
 192
 193                 public static Mutex OpenExisting (string name)
 194                 {
 195                         throw new NotSupportedException ();
 196                 }
 197
 198                 public static Mutex OpenExisting (string name, MutexRights rights)
 199                 {
 200                         throw new NotSupportedException ();
 201                 }
 202
 203                 public static bool TryOpenExisting (string name, out Mutex result)
 204                 {
 205                         throw new NotSupportedException ();
 206                 }
 207
 208                 public static bool TryOpenExisting (string name, MutexRights rights, out Mutex result)
 209                 {
 210                         throw new NotSupportedException ();
 211                 }
 212 #endif
 213
 214                 [ReliabilityContractAttribute (Consistency.WillNotCorruptState, Cer.MayFail)]
 215                 public void ReleaseMutex() {
 216                         bool success = ReleaseMutex_internal(Handle);
 217                         if (!success) {
 218                                 throw new ApplicationException ("Mutex is not owned");
 219                         }
 220                 }
 221
 222 #if !MOBILE
 223                 public void SetAccessControl (MutexSecurity mutexSecurity)
 224                 {
 225                         if (null == mutexSecurity)
 226                                 throw new ArgumentNullException ("mutexSecurity");
 227
 228                         mutexSecurity.PersistModifications (SafeWaitHandle);
 229                 }
 230 #endif
 231         }
 232 }