mcs/class/System.XML/Mono.Xml.Xsl.Operations/XslVariable.cs

   1 //
   2 // XslVariable.cs
   3 //
   4 // Authors:
   5 //      Ben Maurer (bmaurer@users.sourceforge.net)
   6 //      Atsushi Enomoto (ginga@kit.hi-ho.ne.jp)
   7 //
   8 // (C) 2003 Ben Maurer
   9 // (C) 2003 Atsushi Enomoto
  10 //
  11
  12 //
  13 // Permission is hereby granted, free of charge, to any person obtaining
  14 // a copy of this software and associated documentation files (the
  15 // "Software"), to deal in the Software without restriction, including
  16 // without limitation the rights to use, copy, modify, merge, publish,
  17 // distribute, sublicense, and/or sell copies of the Software, and to
  18 // permit persons to whom the Software is furnished to do so, subject to
  19 // the following conditions:
  20 //
  21 // The above copyright notice and this permission notice shall be
  22 // included in all copies or substantial portions of the Software.
  23 //
  24 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  25 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  26 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  27 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  28 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  29 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  30 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  31 //
  32
  33 using System;
  34 using System.Collections;
  35 using System.Xml;
  36 using System.Xml.XPath;
  37 using System.Xml.Xsl;
  38 using Mono.Xml.XPath;
  39
  40 using QName = System.Xml.XmlQualifiedName;
  41
  42 namespace Mono.Xml.Xsl.Operations {
  43
  44         internal class XslVariableInformation
  45         {
  46                 QName name;
  47                 XPathExpression select;
  48                 XslOperation content;
  49
  50                 public XslVariableInformation (Compiler c)
  51                 {
  52                         c.AssertAttribute ("name");
  53                         c.Input.MoveToFirstAttribute ();
  54                         do {
  55                                 if (c.Input.NamespaceURI != String.Empty)
  56                                         continue;
  57                                 switch (c.Input.LocalName) {
  58                                 case "name":
  59                                 case "select":
  60                                         break;
  61                                 default:
  62                                         throw new XsltCompileException ("Invalid attribute " + c.Input.Name, null, c.Input);
  63                                 }
  64                         } while (c.Input.MoveToNextAttribute ());
  65                         c.Input.MoveToParent ();
  66
  67                         name = c.ParseQNameAttribute ("name");
  68                         try {
  69                                 XmlConvert.VerifyName (name.Name);
  70                         } catch (XmlException ex) {
  71                                 throw new XsltCompileException ("Variable name is not qualified name.", ex, c.Input);
  72                         }
  73
  74                         string sel = c.GetAttribute ("select");
  75                         if (sel != null && sel != "" ) {
  76                                 select = c.CompileExpression (c.GetAttribute ("select"));
  77                                 // TODO assert empty
  78                         } else  if (c.Input.MoveToFirstChild ()) {
  79                                 content = c.CompileTemplateContent ();
  80                                 c.Input.MoveToParent ();
  81                         }
  82                 }
  83
  84                 public object Evaluate (XslTransformProcessor p)
  85                 {
  86                         if (select != null) {
  87                                 object o = p.Evaluate (select);
  88                                 // To resolve variable references correctly, we
  89                                 // have to collect all the target nodes here.
  90                                 // (otherwise, variables might be resolved with
  91                                 // different level of variable stack in
  92                                 // XslTransformProcessor).
  93                                 if (o is XPathNodeIterator) {
  94                                         ArrayList al = new ArrayList ();
  95                                         XPathNodeIterator iter = (XPathNodeIterator) o;
  96                                         while (iter.MoveNext ())
  97                                                 al.Add (iter.Current);
  98                                         o = new ListIterator (al, p.XPathContext, false);
  99                                 }
 100                                 return o;
 101                         } else if (content != null) {
 102 //                              XmlNodeWriter w = new XmlNodeWriter (false);
 103                                 DTMXPathDocumentWriter w = new DTMXPathDocumentWriter (p.CurrentNode.NameTable, 200);
 104                                 Outputter outputter = new GenericOutputter(w, p.Outputs, null, true);
 105                                 p.PushOutput (outputter);
 106                                 content.Evaluate (p);
 107                                 p.PopOutput ();
 108 //                              return w.Document.CreateNavigator ().SelectChildren (XPathNodeType.All);
 109 //                              return w.CreateDocument ().CreateNavigator ().SelectChildren (XPathNodeType.All);
 110 //                              return w.Document.CreateNavigator ();
 111                                 return w.CreateDocument ().CreateNavigator ();
 112                         } else {
 113                                 return "";
 114                         }
 115                 }
 116
 117                 public QName Name { get { return name; }}
 118         }
 119
 120         internal abstract class XslGeneralVariable : XslCompiledElement, IXsltContextVariable {
 121                 protected XslVariableInformation var;
 122
 123                 public XslGeneralVariable (Compiler c) : base (c) {}
 124
 125                 protected override void Compile (Compiler c)
 126                 {
 127                         this.var = new XslVariableInformation (c);
 128                 }
 129
 130                 public override abstract void Evaluate (XslTransformProcessor p);
 131                 protected abstract object GetValue (XslTransformProcessor p);
 132
 133
 134                 public object Evaluate (XsltContext xsltContext)
 135                 {
 136                         object value = GetValue (((XsltCompiledContext)xsltContext).Processor);
 137
 138                         if (value is XPathNodeIterator)
 139                                 return ((XPathNodeIterator)value).Clone ();
 140
 141                         return value;
 142                 }
 143
 144                 public QName Name {get {return  var.Name;}}
 145                 public XPathResultType VariableType { get {return XPathResultType.Any;}}
 146                 public abstract bool IsLocal { get; }
 147                 public abstract bool IsParam { get; }
 148         }
 149
 150         internal class XslGlobalVariable : XslGeneralVariable {
 151                 public XslGlobalVariable (Compiler c) : base (c) {}
 152                 static object busyObject = new Object ();
 153
 154
 155                 public override void Evaluate (XslTransformProcessor p)
 156                 {
 157                         Hashtable varInfo = p.globalVariableTable;
 158
 159                         if (varInfo.Contains (this)) {
 160                                 if (varInfo [this] == busyObject)
 161                                         throw new XsltException ("Circular dependency was detected.", null, p.CurrentNode);
 162                                 return;
 163                         }
 164
 165                         varInfo [this] = busyObject;
 166                         varInfo [this] = var.Evaluate (p);
 167
 168                 }
 169
 170                 protected override object GetValue (XslTransformProcessor p)
 171                 {
 172                         Evaluate (p);
 173                         return p.globalVariableTable [this];
 174                 }
 175
 176                 public override bool IsLocal { get { return false; }}
 177                 public override bool IsParam { get { return false; }}
 178         }
 179
 180         internal class XslGlobalParam : XslGlobalVariable {
 181                 bool overriden;
 182                 object paramVal;
 183
 184                 public XslGlobalParam (Compiler c) : base (c) {}
 185
 186                 public void Override (XslTransformProcessor p, object paramVal)
 187                 {
 188                         Debug.Assert (!p.globalVariableTable.Contains (this), "Shouldn't have been evaluated by this point");
 189
 190                         p.globalVariableTable [this] = paramVal;
 191                 }
 192
 193                 public override bool IsParam { get { return true; }}
 194         }
 195
 196         internal class XslLocalVariable : XslGeneralVariable {
 197                 protected int slot;
 198
 199                 public XslLocalVariable (Compiler c) : base (c)
 200                 {
 201                         slot = c.AddVariable (this);
 202                 }
 203
 204                 public override void Evaluate (XslTransformProcessor p)
 205                 {
 206                         p.SetStackItem (slot, var.Evaluate (p));
 207                 }
 208
 209                 protected override object GetValue (XslTransformProcessor p)
 210                 {
 211                         return p.GetStackItem (slot);
 212                 }
 213
 214                 public bool IsEvaluated (XslTransformProcessor p)
 215                 {
 216                         return p.GetStackItem (slot) != null;
 217                 }
 218
 219                 public override bool IsLocal { get { return true; }}
 220                 public override bool IsParam { get { return false; }}
 221         }
 222
 223         internal class XslLocalParam : XslLocalVariable {
 224                 bool overriden;
 225                 object paramVal;
 226
 227                 public XslLocalParam (Compiler c) : base (c) {}
 228
 229                 public override void Evaluate (XslTransformProcessor p)
 230                 {
 231                         if (p.GetStackItem (slot) != null)
 232                                 return; // evaluated already
 233
 234                         base.Evaluate (p);
 235                 }
 236
 237                 public void Override (XslTransformProcessor p, object paramVal)
 238                 {
 239                         p.SetStackItem (slot, paramVal);
 240                 }
 241
 242                 public override bool IsParam { get { return true; }}
 243         }
 244
 245         internal class XPathVariableBinding : Expression {
 246                 XslGeneralVariable v;
 247                 public XPathVariableBinding (XslGeneralVariable v)
 248                 {
 249                         this.v = v;
 250                 }
 251                 public override String ToString () { return "$" + v.Name.ToString (); }
 252                 public override XPathResultType ReturnType { get { return XPathResultType.Any; }}
 253                 public override XPathResultType GetReturnType (BaseIterator iter)
 254                 {
 255                         return XPathResultType.Any;
 256                 }
 257
 258                 public override object Evaluate (BaseIterator iter)
 259                 {
 260                         return v.Evaluate (iter.NamespaceManager as XsltContext);
 261                 }
 262         }
 263 }