mcs/class/Microsoft.Build.Engine/Microsoft.Build.BuildEngine/ConditionParser.cs

   1 //
   2 // ConditionParser.cs
   3 //
   4 // Author:
   5 //   Marek Sieradzki (marek.sieradzki@gmail.com)
   6 //   Jaroslaw Kowalski <jaak@jkowalski.net>
   7 //
   8 // (C) 2006 Marek Sieradzki
   9 // (C) 2004-2006 Jaroslaw Kowalski
  10 //
  11 // Permission is hereby granted, free of charge, to any person obtaining
  12 // a copy of this software and associated documentation files (the
  13 // "Software"), to deal in the Software without restriction, including
  14 // without limitation the rights to use, copy, modify, merge, publish,
  15 // distribute, sublicense, and/or sell copies of the Software, and to
  16 // permit persons to whom the Software is furnished to do so, subject to
  17 // the following conditions:
  18 //
  19 // The above copyright notice and this permission notice shall be
  20 // included in all copies or substantial portions of the Software.
  21 //
  22 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  23 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  24 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  25 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  26 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  27 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  28 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  29
  30 #if NET_2_0
  31
  32 using System;
  33 using System.Collections;
  34 using System.Text;
  35
  36 namespace Microsoft.Build.BuildEngine {
  37
  38         internal class ConditionParser {
  39
  40                 ConditionTokenizer tokenizer = new ConditionTokenizer ();
  41
  42                 private ConditionParser (string condition)
  43                 {
  44                         tokenizer.Tokenize (condition);
  45                 }
  46
  47                 public static ConditionExpression ParseCondition (string condition)
  48                 {
  49                         ConditionParser parser = new ConditionParser (condition);
  50                         ConditionExpression e = parser.ParseExpression ();
  51
  52                         if (!parser.tokenizer.IsEOF ())
  53                                 throw new ExpressionParseException (String.Format ("Unexpected token: {0}", parser.tokenizer.Token.Value));
  54
  55                         return e;
  56                 }
  57
  58                 private ConditionExpression ParseExpression ()
  59                 {
  60                         return ParseBooleanExpression ();
  61                 }
  62
  63                 private ConditionExpression ParseBooleanExpression ()
  64                 {
  65                         return ParseBooleanAnd ();
  66                 }
  67
  68                 private ConditionExpression ParseBooleanAnd ()
  69                 {
  70                         ConditionExpression e = ParseBooleanOr ();
  71
  72                         while (tokenizer.IsToken (TokenType.And)) {
  73                                 tokenizer.GetNextToken ();
  74                                 e = new ConditionAndExpression ((ConditionExpression) e, (ConditionExpression) ParseBooleanOr ());
  75                         }
  76
  77                         return e;
  78                 }
  79
  80                 private ConditionExpression ParseBooleanOr ()
  81                 {
  82                         ConditionExpression e = ParseRelationalExpression ();
  83
  84                         while (tokenizer.IsToken (TokenType.Or)) {
  85                                 tokenizer.GetNextToken ();
  86                                 e = new ConditionOrExpression ((ConditionExpression) e, (ConditionExpression) ParseRelationalExpression ());
  87                         }
  88
  89                         return e;
  90                 }
  91
  92                 private ConditionExpression ParseRelationalExpression ()
  93                 {
  94                         ConditionExpression e = ParseFactorExpression ();
  95                         Token opToken;
  96                         RelationOperator op;
  97
  98                         if (tokenizer.IsToken (TokenType.Less) ||
  99                                 tokenizer.IsToken (TokenType.Greater) ||
 100                                 tokenizer.IsToken (TokenType.Equal) ||
 101                                 tokenizer.IsToken (TokenType.NotEqual) ||
 102                                 tokenizer.IsToken (TokenType.LessOrEqual) ||
 103                                 tokenizer.IsToken (TokenType.GreaterOrEqual)) {
 104
 105                                 opToken = tokenizer.Token;
 106                                 tokenizer.GetNextToken ();
 107
 108                                 switch (opToken.Type) {
 109                                 case TokenType.Equal:
 110                                         op = RelationOperator.Equal;
 111                                         break;
 112                                 case TokenType.NotEqual:
 113                                         op = RelationOperator.NotEqual;
 114                                         break;
 115                                 case TokenType.Less:
 116                                         op = RelationOperator.Less;
 117                                         break;
 118                                 case TokenType.LessOrEqual:
 119                                         op = RelationOperator.LessOrEqual;
 120                                         break;
 121                                 case TokenType.Greater:
 122                                         op = RelationOperator.Greater;
 123                                         break;
 124                                 case TokenType.GreaterOrEqual:
 125                                         op = RelationOperator.GreaterOrEqual;
 126                                         break;
 127                                 default:
 128                                         throw new ExpressionParseException (String.Format ("Wrong relation operator {0}", opToken.Value));
 129                                 }
 130
 131                                 e =  new ConditionRelationalExpression ((ConditionExpression) e, ParseFactorExpression (), op);
 132                         }
 133
 134                         return e;
 135                 }
 136
 137                 // FIXME: parse sub expression in parens, parse TokenType.Not, parse functions
 138                 private ConditionExpression ParseFactorExpression ()
 139                 {
 140                         Token token = tokenizer.Token;
 141                         tokenizer.GetNextToken ();
 142
 143                         if (token.Type != TokenType.String && token.Type != TokenType.Number)
 144                                 throw new ExpressionParseException (String.Format ("Unexpected token type {0}.", token.Type));
 145
 146                         return new ConditionFactorExpression (token);
 147                 }
 148         }
 149 }
 150
 151 #endif