mcs/class/Mono.Posix/Mono.Unix/UnixSignal.cs

   1 //
   2 // Mono.Unix/UnixSignal.cs
   3 //
   4 // Authors:
   5 //   Jonathan Pryor (jpryor@novell.com)
   6 //   Tim Jenks (tim.jenks@realtimeworlds.com)
   7 //
   8 // (C) 2008 Novell, Inc.
   9 //
  10 // Permission is hereby granted, free of charge, to any person obtaining
  11 // a copy of this software and associated documentation files (the
  12 // "Software"), to deal in the Software without restriction, including
  13 // without limitation the rights to use, copy, modify, merge, publish,
  14 // distribute, sublicense, and/or sell copies of the Software, and to
  15 // permit persons to whom the Software is furnished to do so, subject to
  16 // the following conditions:
  17 //
  18 // The above copyright notice and this permission notice shall be
  19 // included in all copies or substantial portions of the Software.
  20 //
  21 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  22 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  23 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  24 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  25 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  26 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  27 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  28 //
  29
  30 using System;
  31 using System.Runtime.InteropServices;
  32 using System.Threading;
  33
  34 using Mono.Unix.Native;
  35
  36 namespace Mono.Unix {
  37
  38         public class UnixSignal : WaitHandle {
  39                 private int signum;
  40                 private IntPtr signal_info;
  41
  42                 static UnixSignal ()
  43                 {
  44                         Stdlib.VersionCheck ();
  45                 }
  46
  47                 public UnixSignal (Signum signum)
  48                 {
  49                         this.signum = NativeConvert.FromSignum (signum);
  50                         this.signal_info = install (this.signum);
  51                         if (this.signal_info == IntPtr.Zero) {
  52                                 throw new ArgumentException ("Unable to handle signal", "signum");
  53                         }
  54                 }
  55
  56                 public UnixSignal (Mono.Unix.Native.RealTimeSignum rtsig)
  57                 {
  58                         signum = NativeConvert.FromRealTimeSignum (rtsig);
  59                         this.signal_info = install (this.signum);
  60                         Native.Errno err = Native.Stdlib.GetLastError ();
  61                         if (this.signal_info == IntPtr.Zero) {
  62                                 if (err == Native.Errno.EADDRINUSE)
  63                                         throw new ArgumentException ("Signal registered outside of Mono.Posix", "signum");
  64                                 throw new ArgumentException ("Unable to handle signal", "signum");
  65                         }
  66                 }
  67
  68                 public Signum Signum {
  69                         get {
  70                                 if (IsRealTimeSignal)
  71                                         throw new InvalidOperationException ("This signal is a RealTimeSignum");
  72                                 return NativeConvert.ToSignum (signum);
  73                         }
  74                 }
  75
  76                 public RealTimeSignum RealTimeSignum {
  77                         get {
  78                                 if (!IsRealTimeSignal)
  79                                         throw new InvalidOperationException ("This signal is not a RealTimeSignum");
  80                                 return NativeConvert.ToRealTimeSignum (signum-GetSIGRTMIN ());
  81                         }
  82                 }
  83
  84                 public bool IsRealTimeSignal {
  85                         get {
  86                                 AssertValid ();
  87                                 int sigrtmin = GetSIGRTMIN ();
  88                                 if (sigrtmin == -1)
  89                                         return false;
  90                                 return signum >= sigrtmin;
  91                         }
  92                 }
  93
  94                 [DllImport (Stdlib.MPH, CallingConvention=CallingConvention.Cdecl,
  95                                 EntryPoint="Mono_Unix_UnixSignal_install", SetLastError=true)]
  96                 private static extern IntPtr install (int signum);
  97
  98                 [DllImport (Stdlib.MPH, CallingConvention=CallingConvention.Cdecl,
  99                                 EntryPoint="Mono_Unix_UnixSignal_uninstall")]
 100                 private static extern int uninstall (IntPtr info);
 101
 102                 [UnmanagedFunctionPointer (CallingConvention.Cdecl)]
 103                 delegate int Mono_Posix_RuntimeIsShuttingDown ();
 104                 static Mono_Posix_RuntimeIsShuttingDown ShuttingDown = RuntimeShuttingDownCallback;
 105
 106                 static int RuntimeShuttingDownCallback ()
 107                 {
 108                         return Environment.HasShutdownStarted ? 1 : 0;
 109                 }
 110
 111                 [DllImport (Stdlib.MPH, CallingConvention=CallingConvention.Cdecl,
 112                                 EntryPoint="Mono_Unix_UnixSignal_WaitAny")]
 113                 private static extern int WaitAny (IntPtr[] infos, int count, int timeout, Mono_Posix_RuntimeIsShuttingDown shutting_down);
 114
 115                 [DllImport (Stdlib.MPH, CallingConvention=CallingConvention.Cdecl,
 116                                 EntryPoint="Mono_Posix_SIGRTMIN")]
 117                 internal static extern int GetSIGRTMIN ();
 118
 119                 [DllImport (Stdlib.MPH, CallingConvention=CallingConvention.Cdecl,
 120                                 EntryPoint="Mono_Posix_SIGRTMAX")]
 121                 internal static extern int GetSIGRTMAX ();
 122
 123                 private void AssertValid ()
 124                 {
 125                         if (signal_info == IntPtr.Zero)
 126                                 throw new ObjectDisposedException (GetType().FullName);
 127                 }
 128
 129                 private unsafe SignalInfo* Info {
 130                         get {
 131                                 AssertValid ();
 132                                 return (SignalInfo*) signal_info;
 133                         }
 134                 }
 135
 136                 public bool IsSet {
 137                         get {
 138                                 return Count > 0;
 139                         }
 140                 }
 141
 142                 public unsafe bool Reset ()
 143                 {
 144                         int n = Interlocked.Exchange (ref Info->count, 0);
 145                         return n != 0;
 146                 }
 147
 148                 public unsafe int Count {
 149                         get {return Info->count;}
 150                         set {Interlocked.Exchange (ref Info->count, value);}
 151                 }
 152
 153                 // signum, count, write_fd, pipecnt, and pipelock are read from a signal handler thread
 154                 // count and pipelock are both read and written from the signal handler thread
 155                 [Map]
 156                 struct SignalInfo {
 157                         public int signum, count, read_fd, write_fd, pipecnt, pipelock, have_handler;
 158                         public IntPtr handler; // Backed-up handler to restore when signal unregistered
 159                 }
 160
 161                 #region WaitHandle overrides
 162                 protected unsafe override void Dispose (bool disposing)
 163                 {
 164                         base.Dispose (disposing);
 165                         if (signal_info == IntPtr.Zero)
 166                                 return;
 167                         uninstall (signal_info);
 168                         signal_info = IntPtr.Zero;
 169                 }
 170
 171                 public override bool WaitOne ()
 172                 {
 173                         return WaitOne (-1, false);
 174                 }
 175
 176                 public override bool WaitOne (TimeSpan timeout, bool exitContext)
 177                 {
 178                         long ms = (long) timeout.TotalMilliseconds;
 179                         if (ms < -1 || ms > Int32.MaxValue)
 180                                 throw new ArgumentOutOfRangeException ("timeout");
 181                         return WaitOne ((int) ms, exitContext);
 182                 }
 183
 184                 public override bool WaitOne (int millisecondsTimeout, bool exitContext)
 185                 {
 186                         AssertValid ();
 187                         if (exitContext)
 188                                 throw new InvalidOperationException ("exitContext is not supported");
 189                         return WaitAny (new UnixSignal[]{this}, millisecondsTimeout) == 0;
 190                 }
 191                 #endregion
 192
 193                 public static int WaitAny (UnixSignal[] signals)
 194                 {
 195                         return WaitAny (signals, -1);
 196                 }
 197
 198                 public static int WaitAny (UnixSignal[] signals, TimeSpan timeout)
 199                 {
 200                         long ms = (long) timeout.TotalMilliseconds;
 201                         if (ms < -1 || ms > Int32.MaxValue)
 202                                 throw new ArgumentOutOfRangeException ("timeout");
 203                         return WaitAny (signals, (int) ms);
 204                 }
 205
 206
 207                 public static unsafe int WaitAny (UnixSignal[] signals, int millisecondsTimeout)
 208                 {
 209                         if (signals == null)
 210                                 throw new ArgumentNullException ("signals");
 211                         if (millisecondsTimeout < -1)
 212                                 throw new ArgumentOutOfRangeException ("millisecondsTimeout");
 213                         IntPtr[] infos = new IntPtr [signals.Length];
 214                         for (int i = 0; i < signals.Length; ++i) {
 215                                 infos [i] = signals [i].signal_info;
 216                                 if (infos [i] == IntPtr.Zero)
 217                                         throw new InvalidOperationException ("Disposed UnixSignal");
 218                         }
 219                         return WaitAny (infos, infos.Length, millisecondsTimeout, ShuttingDown);
 220                 }
 221         }
 222 }
 223