mcs/class/System.Xaml/System.Xaml/XamlBackgroundReader.cs

   1 //
   2 // Copyright (C) 2011 Novell Inc. http://novell.com
   3 //
   4 // Permission is hereby granted, free of charge, to any person obtaining
   5 // a copy of this software and associated documentation files (the
   6 // "Software"), to deal in the Software without restriction, including
   7 // without limitation the rights to use, copy, modify, merge, publish,
   8 // distribute, sublicense, and/or sell copies of the Software, and to
   9 // permit persons to whom the Software is furnished to do so, subject to
  10 // the following conditions:
  11 //
  12 // The above copyright notice and this permission notice shall be
  13 // included in all copies or substantial portions of the Software.
  14 //
  15 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  16 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  17 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  18 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  19 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  20 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  21 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  22 //
  23 using System;
  24 using System.Collections.Generic;
  25 using System.Threading;
  26
  27 namespace System.Xaml
  28 {
  29         public class XamlBackgroundReader : XamlReader, IXamlLineInfo
  30         {
  31                 public XamlBackgroundReader (XamlReader wrappedReader)
  32                 {
  33                         if (wrappedReader == null)
  34                                 throw new ArgumentNullException ("wrappedReader");
  35                         r = wrappedReader;
  36                         q = new XamlNodeQueue (r.SchemaContext) { LineInfoProvider = r as IXamlLineInfo };
  37                 }
  38
  39                 Thread thread;
  40                 XamlReader r;
  41                 XamlNodeQueue q;
  42                 bool read_all_done, do_work = true;
  43                 ManualResetEvent wait = new ManualResetEvent (true);
  44
  45                 public bool HasLineInfo {
  46                         get { return ((IXamlLineInfo) q.Reader).HasLineInfo; }
  47                 }
  48
  49                 public override bool IsEof {
  50                         get { return read_all_done && q.IsEmpty; }
  51                 }
  52
  53                 public int LineNumber {
  54                         get { return ((IXamlLineInfo) q.Reader).LineNumber; }
  55                 }
  56
  57                 [MonoTODO ("always returns 0")]
  58                 public int LinePosition {
  59                         get { return ((IXamlLineInfo) q.Reader).LinePosition; }
  60                 }
  61
  62                 public override XamlMember Member {
  63                         get { return q.Reader.Member; }
  64                 }
  65
  66                 public override NamespaceDeclaration Namespace {
  67                         get { return q.Reader.Namespace; }
  68                 }
  69
  70                 public override XamlNodeType NodeType {
  71                         get { return q.Reader.NodeType; }
  72                 }
  73
  74                 public override XamlSchemaContext SchemaContext {
  75                         get { return q.Reader.SchemaContext; }
  76                 }
  77
  78                 public override XamlType Type {
  79                         get { return q.Reader.Type; }
  80                 }
  81
  82                 public override object Value {
  83                         get { return q.Reader.Value; }
  84                 }
  85
  86                 protected override void Dispose (bool disposing)
  87                 {
  88                         do_work = false;
  89                 }
  90
  91                 public override bool Read ()
  92                 {
  93                         if (q.IsEmpty)
  94                                 wait.WaitOne ();
  95                         return q.Reader.Read ();
  96                 }
  97
  98                 public void StartThread ()
  99                 {
 100                         StartThread ("XAML reader thread"); // documented name
 101                 }
 102
 103                 public void StartThread (string threadName)
 104                 {
 105                         if (thread != null)
 106                                 throw new InvalidOperationException ("Thread has already started");
 107                         thread = new Thread (new ParameterizedThreadStart (delegate {
 108                                 while (do_work && r.Read ()) {
 109                                         q.Writer.WriteNode (r);
 110                                         wait.Set ();
 111                                 }
 112                                 read_all_done = true;
 113                         })) { Name = threadName };
 114                         thread.Start ();
 115                 }
 116         }
 117 }