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                 public UnixSignal (Signum signum)
  43                 {
  44                         this.signum = NativeConvert.FromSignum (signum);
  45                         this.signal_info = install (this.signum);
  46                         if (this.signal_info == IntPtr.Zero) {
  47                                 throw new ArgumentException ("Unable to handle signal", "signum");
  48                         }
  49                 }
  50
  51                 public UnixSignal (Mono.Unix.Native.RealTimeSignum rtsig)
  52                 {
  53                         signum = NativeConvert.FromRealTimeSignum (rtsig);
  54                         this.signal_info = install (this.signum);
  55                         Native.Errno err = Native.Stdlib.GetLastError ();
  56                         if (this.signal_info == IntPtr.Zero) {
  57                                 if (err == Native.Errno.EADDRINUSE)
  58                                         throw new ArgumentException ("Signal registered outside of Mono.Posix", "signum");
  59                                 throw new ArgumentException ("Unable to handle signal", "signum");
  60                         }
  61                 }
  62
  63                 public Signum Signum {
  64                         get {
  65                                 if (IsRealTimeSignal)
  66                                         throw new InvalidOperationException ("This signal is a RealTimeSignum");
  67                                 return NativeConvert.ToSignum (signum);
  68                         }
  69                 }
  70
  71                 public RealTimeSignum RealTimeSignum {
  72                         get {
  73                                 if (!IsRealTimeSignal)
  74                                         throw new InvalidOperationException ("This signal is not a RealTimeSignum");
  75                                 return NativeConvert.ToRealTimeSignum (signum-GetSIGRTMIN ());
  76                         }
  77                 }
  78
  79                 public bool IsRealTimeSignal {
  80                         get {
  81                                 AssertValid ();
  82                                 int sigrtmin = GetSIGRTMIN ();
  83                                 if (sigrtmin == -1)
  84                                         return false;
  85                                 return signum >= sigrtmin;
  86                         }
  87                 }
  88
  89                 [DllImport (Stdlib.MPH, CallingConvention=CallingConvention.Cdecl,
  90                                 EntryPoint="Mono_Unix_UnixSignal_install", SetLastError=true)]
  91                 private static extern IntPtr install (int signum);
  92
  93                 [DllImport (Stdlib.MPH, CallingConvention=CallingConvention.Cdecl,
  94                                 EntryPoint="Mono_Unix_UnixSignal_uninstall")]
  95                 private static extern int uninstall (IntPtr info);
  96
  97                 [UnmanagedFunctionPointer (CallingConvention.Cdecl)]
  98                 delegate int Mono_Posix_RuntimeIsShuttingDown ();
  99
 100                 [DllImport (Stdlib.MPH, CallingConvention=CallingConvention.Cdecl,
 101                                 EntryPoint="Mono_Unix_UnixSignal_WaitAny")]
 102                 private static extern int WaitAny (IntPtr[] infos, int count, int timeout, Mono_Posix_RuntimeIsShuttingDown shutting_down);
 103
 104                 [DllImport (Stdlib.MPH, CallingConvention=CallingConvention.Cdecl,
 105                                 EntryPoint="Mono_Posix_SIGRTMIN")]
 106                 internal static extern int GetSIGRTMIN ();
 107
 108                 [DllImport (Stdlib.MPH, CallingConvention=CallingConvention.Cdecl,
 109                                 EntryPoint="Mono_Posix_SIGRTMAX")]
 110                 internal static extern int GetSIGRTMAX ();
 111
 112                 private void AssertValid ()
 113                 {
 114                         if (signal_info == IntPtr.Zero)
 115                                 throw new ObjectDisposedException (GetType().FullName);
 116                 }
 117
 118                 private unsafe SignalInfo* Info {
 119                         get {
 120                                 AssertValid ();
 121                                 return (SignalInfo*) signal_info;
 122                         }
 123                 }
 124
 125                 public bool IsSet {
 126                         get {
 127                                 return Count > 0;
 128                         }
 129                 }
 130
 131                 public unsafe bool Reset ()
 132                 {
 133                         int n = Interlocked.Exchange (ref Info->count, 0);
 134                         return n != 0;
 135                 }
 136
 137                 public unsafe int Count {
 138                         get {return Info->count;}
 139                         set {Interlocked.Exchange (ref Info->count, value);}
 140                 }
 141
 142                 [Map]
 143                 struct SignalInfo {
 144                         public int signum, count, read_fd, write_fd, have_handler, pipecnt;
 145                         public IntPtr handler;
 146                 }
 147
 148                 #region WaitHandle overrides
 149                 protected unsafe override void Dispose (bool disposing)
 150                 {
 151                         base.Dispose (disposing);
 152                         if (signal_info == IntPtr.Zero)
 153                                 return;
 154                         uninstall (signal_info);
 155                         signal_info = IntPtr.Zero;
 156                 }
 157
 158                 public override bool WaitOne ()
 159                 {
 160                         return WaitOne (-1, false);
 161                 }
 162
 163                 public override bool WaitOne (TimeSpan timeout, bool exitContext)
 164                 {
 165                         long ms = (long) timeout.TotalMilliseconds;
 166                         if (ms < -1 || ms > Int32.MaxValue)
 167                                 throw new ArgumentOutOfRangeException ("timeout");
 168                         return WaitOne ((int) ms, exitContext);
 169                 }
 170
 171                 public override bool WaitOne (int millisecondsTimeout, bool exitContext)
 172                 {
 173                         AssertValid ();
 174                         if (exitContext)
 175                                 throw new InvalidOperationException ("exitContext is not supported");
 176                         return WaitAny (new UnixSignal[]{this}, millisecondsTimeout) == 0;
 177                 }
 178                 #endregion
 179
 180                 public static int WaitAny (UnixSignal[] signals)
 181                 {
 182                         return WaitAny (signals, -1);
 183                 }
 184
 185                 public static int WaitAny (UnixSignal[] signals, TimeSpan timeout)
 186                 {
 187                         long ms = (long) timeout.TotalMilliseconds;
 188                         if (ms < -1 || ms > Int32.MaxValue)
 189                                 throw new ArgumentOutOfRangeException ("timeout");
 190                         return WaitAny (signals, (int) ms);
 191                 }
 192
 193                 public static unsafe int WaitAny (UnixSignal[] signals, int millisecondsTimeout)
 194                 {
 195                         if (signals == null)
 196                                 throw new ArgumentNullException ("signals");
 197                         if (millisecondsTimeout < -1)
 198                                 throw new ArgumentOutOfRangeException ("millisecondsTimeout");
 199                         IntPtr[] infos = new IntPtr [signals.Length];
 200                         for (int i = 0; i < signals.Length; ++i) {
 201                                 infos [i] = signals [i].signal_info;
 202                                 if (infos [i] == IntPtr.Zero)
 203                                         throw new InvalidOperationException ("Disposed UnixSignal");
 204                         }
 205                         return WaitAny (infos, infos.Length, millisecondsTimeout, () => Environment.HasShutdownStarted ? 1 : 0);
 206                 }
 207         }
 208 }
 209