mcs/class/Managed.Windows.Forms/System.Windows.Forms/XEventQueue.cs

   1 // Permission is hereby granted, free of charge, to any person obtaining
   2 // a copy of this software and associated documentation files (the
   3 // "Software"), to deal in the Software without restriction, including
   4 // without limitation the rights to use, copy, modify, merge, publish,
   5 // distribute, sublicense, and/or sell copies of the Software, and to
   6 // permit persons to whom the Software is furnished to do so, subject to
   7 // the following conditions:
   8 //
   9 // The above copyright notice and this permission notice shall be
  10 // included in all copies or substantial portions of the Software.
  11 //
  12 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  13 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  14 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  15 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  16 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  17 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  18 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  19 //
  20 // Copyright (c) 2004-2006 Novell, Inc.
  21 //
  22 // System.Windows.Forms.XEventQueue
  23 //
  24 // Authors:
  25 //  Jackson Harper (jackson@ximian.com)
  26 //  Peter Dennis Bartok (pbartok@novell.com)
  27 //
  28
  29 using System;
  30 using System.Threading;
  31 using System.Collections;
  32
  33 namespace System.Windows.Forms {
  34
  35         internal class XEventQueue {
  36
  37                 private XQueue          xqueue;
  38                 private XQueue          lqueue; // Events inserted from threads other then the main X thread
  39                 private PaintQueue      paint;  // Paint-only queue
  40                 internal ArrayList      timer_list;
  41                 private Thread          thread;
  42                 private bool            quit_posted;
  43                 private bool            dispatch_idle;
  44
  45                 private static readonly int InitialXEventSize = 100;
  46                 private static readonly int InitialLXEventSize = 10;
  47                 private static readonly int InitialPaintSize = 50;
  48
  49                 public XEventQueue (Thread thread) {
  50                         xqueue = new XQueue (InitialXEventSize);
  51                         lqueue = new XQueue (InitialLXEventSize);
  52                         paint = new PaintQueue(InitialPaintSize);
  53                         timer_list = new ArrayList ();
  54                         this.thread = thread;
  55                         this.quit_posted = false;
  56                         this.dispatch_idle = true;
  57                 }
  58
  59                 public int Count {
  60                         get {
  61                                 lock (lqueue) {
  62                                         return xqueue.Count + lqueue.Count;
  63                                 }
  64                         }
  65                 }
  66
  67                 public PaintQueue Paint {
  68                         get {
  69                                 return paint;
  70                         }
  71                 }
  72
  73                 public Thread Thread {
  74                         get {
  75                                 return thread;
  76                         }
  77                 }
  78
  79                 public void Enqueue (XEvent xevent)
  80                 {
  81                         if (Thread.CurrentThread != thread) {
  82                                 Console.WriteLine ("Hwnd.Queue.Enqueue called from a different thread without locking.");
  83                                 Console.WriteLine (Environment.StackTrace);
  84                         }
  85
  86                         xqueue.Enqueue (xevent);
  87                 }
  88
  89                 public void EnqueueLocked (XEvent xevent)
  90                 {
  91                         lock (lqueue) {
  92                                 lqueue.Enqueue (xevent);
  93                         }
  94                 }
  95
  96                 public XEvent Dequeue ()
  97                 {
  98                         if (Thread.CurrentThread != thread) {
  99                                 Console.WriteLine ("Hwnd.Queue.Dequeue called from a different thread without locking.");
 100                                 Console.WriteLine (Environment.StackTrace);
 101                         }
 102
 103                         if (xqueue.Count == 0) {
 104                                 lock (lqueue) {
 105                                         return lqueue.Dequeue ();
 106                                 }
 107                         }
 108                         return xqueue.Dequeue ();
 109                 }
 110
 111                 public XEvent Peek()
 112                 {
 113                         if (Thread.CurrentThread != thread) {
 114                                 Console.WriteLine ("Hwnd.Queue.Peek called from a different thread without locking.");
 115                                 Console.WriteLine (Environment.StackTrace);
 116                         }
 117
 118                         if (xqueue.Count == 0) {
 119                                 lock (lqueue) {
 120                                         return lqueue.Peek ();
 121                                 }
 122                         }
 123                         return xqueue.Peek();
 124                 }
 125
 126                 public bool DispatchIdle {
 127                         get {
 128                                 return dispatch_idle;
 129                         }
 130                         set {
 131                                 dispatch_idle = value;
 132                         }
 133                 }
 134
 135                 public bool PostQuitState {
 136                         get {
 137                                 return quit_posted;
 138                         }
 139
 140                         set {
 141                                 quit_posted = value;
 142                         }
 143                 }
 144
 145                 public class PaintQueue {
 146
 147                         private ArrayList       hwnds;
 148                         private XEvent          xevent;
 149
 150                         public PaintQueue (int size) {
 151                                 hwnds = new ArrayList(size);
 152                                 xevent = new XEvent();
 153                                 xevent.AnyEvent.type = XEventName.Expose;
 154                         }
 155
 156                         public int Count {
 157                                 get { return hwnds.Count; }
 158                         }
 159
 160                         public void Enqueue (Hwnd hwnd) {
 161                                 hwnds.Add(hwnd);
 162                         }
 163
 164                         public void Remove(Hwnd hwnd) {
 165                                 if (!hwnd.expose_pending && !hwnd.nc_expose_pending) {
 166                                         hwnds.Remove(hwnd);
 167                                 }
 168                         }
 169
 170                         public XEvent Dequeue () {
 171                                 Hwnd            hwnd;
 172                                 IEnumerator     next;
 173
 174                                 if (hwnds.Count == 0) {
 175                                         xevent.ExposeEvent.window = IntPtr.Zero;
 176                                         return xevent;
 177                                 }
 178
 179                                 next = hwnds.GetEnumerator();
 180                                 next.MoveNext();
 181                                 hwnd = (Hwnd)next.Current;
 182
 183                                 // We only remove the event from the queue if we have one expose left since
 184                                 // a single 'entry in our queue may be for both NC and Client exposed
 185                                 if ( !(hwnd.nc_expose_pending && hwnd.expose_pending)) {
 186                                         hwnds.Remove(hwnd);
 187                                 }
 188                                 if (hwnd.expose_pending) {
 189                                         xevent.ExposeEvent.window = hwnd.client_window;
 190 #if not
 191                                         xevent.ExposeEvent.x = hwnd.invalid.X;
 192                                         xevent.ExposeEvent.y = hwnd.invalid.Y;
 193                                         xevent.ExposeEvent.width = hwnd.invalid.Width;
 194                                         xevent.ExposeEvent.height = hwnd.invalid.Height;
 195 #endif
 196                                         return xevent;
 197                                 } else {
 198                                         xevent.ExposeEvent.window = hwnd.whole_window;
 199                                         xevent.ExposeEvent.x = hwnd.nc_invalid.X;
 200                                         xevent.ExposeEvent.y = hwnd.nc_invalid.Y;
 201                                         xevent.ExposeEvent.width = hwnd.nc_invalid.Width;
 202                                         xevent.ExposeEvent.height = hwnd.nc_invalid.Height;
 203                                         return xevent;
 204                                 }
 205                         }
 206                 }
 207
 208                 private class XQueue {
 209
 210                         private XEvent [] xevents;
 211                         private int head;
 212                         private int tail;
 213                         private int size;
 214
 215                         public XQueue (int size)
 216                         {
 217                                 xevents = new XEvent [size];
 218                         }
 219
 220                         public int Count {
 221                                 get { return size; }
 222                         }
 223
 224                         public void Enqueue (XEvent xevent)
 225                         {
 226                                 if (size == xevents.Length)
 227                                         Grow ();
 228
 229                                 xevents [tail] = xevent;
 230                                 tail = (tail + 1) % xevents.Length;
 231                                 size++;
 232                         }
 233
 234                         public XEvent Dequeue ()
 235                         {
 236                                 if (size < 1)
 237                                         throw new Exception ("Attempt to dequeue empty queue.");
 238                                 XEvent res = xevents [head];
 239                                 head = (head + 1) % xevents.Length;
 240                                 size--;
 241                                 return res;
 242                         }
 243
 244                         public XEvent Peek() {
 245                                 if (size < 1) {
 246                                         throw new Exception ("Attempt to peek at empty queue");
 247                                 }
 248                                 return xevents[head];
 249                         }
 250
 251                         private void Grow ()
 252                         {
 253                                 int newcap = (xevents.Length * 2);
 254                                 XEvent [] na = new XEvent [newcap];
 255                                 xevents.CopyTo (na, 0);
 256                                 xevents = na;
 257                                 head = 0;
 258                                 tail = head + size;
 259                         }
 260                 }
 261         }
 262 }
 263