mcs/mcs/attribute.cs

   1 //\r
   2 // attribute.cs: Attribute Handler\r
   3 //\r
   4 // Author: Ravi Pratap (ravi@ximian.com)\r
   5 //\r
   6 // Licensed under the terms of the GNU GPL\r
   7 //\r
   8 // (C) 2001 Ximian, Inc (http://www.ximian.com)\r
   9 //\r
  10 //\r
  11 \r
  12 using System;\r
  13 using System.Collections;\r
  14 using System.Reflection;\r
  15 using System.Reflection.Emit;\r
  16 \r
  17 namespace CIR {\r
  18 \r
  19         public class Attribute {\r
  20                 \r
  21                 public readonly string    Name;\r
  22                 public readonly ArrayList Arguments;\r
  23 \r
  24                 Location Location;\r
  25                 \r
  26                 public Attribute (string name, ArrayList args, Location loc)\r
  27                 {\r
  28                         Name = name;\r
  29                         Arguments = args;\r
  30                         Location = loc;\r
  31                 }\r
  32 \r
  33                 void error617 (string name)\r
  34                 {\r
  35                         Report.Error (617, Location, "'" + name + "' is not a valid named attribute " +\r
  36                                       "argument. Named attribute arguments must be fields which are not " +\r
  37                                       "readonly, static or const, or properties with a set accessor which "+\r
  38                                       "are not static.");\r
  39                 }\r
  40 \r
  41                 void error182 ()\r
  42                 {\r
  43                         Report.Error (182, Location,\r
  44                                       "An attribute argument must be a constant expression, typeof " +\r
  45                                       "expression or array creation expression");\r
  46                 }\r
  47 \r
  48                 public CustomAttributeBuilder Resolve (EmitContext ec)\r
  49                 {\r
  50                         string name = Name;\r
  51 \r
  52                         if (Name.IndexOf ("Attribute") == -1)\r
  53                                 name = Name + "Attribute";\r
  54                         else if (Name.LastIndexOf ("Attribute") == 0)\r
  55                                 name = Name + "Attribute";\r
  56                         \r
  57                         Type attribute_type = ec.TypeContainer.LookupType (name, false);\r
  58 \r
  59                         if (attribute_type == null) {\r
  60                                 Report.Error (246, Location, "Could not find attribute '" + Name + "' (are you" +\r
  61                                               " missing a using directive or an assembly reference ?)");\r
  62                                 return null;\r
  63                         }\r
  64                         \r
  65                         // Now we extract the positional and named arguments\r
  66                         \r
  67                         ArrayList pos_args = new ArrayList ();\r
  68                         ArrayList named_args = new ArrayList ();\r
  69                         \r
  70                         if (Arguments != null) {\r
  71                                 pos_args = (ArrayList) Arguments [0];\r
  72                                 if (Arguments.Count > 1)\r
  73                                         named_args = (ArrayList) Arguments [1];\r
  74                         }\r
  75                                 \r
  76                         object [] pos_values = new object [pos_args.Count];\r
  77 \r
  78                         //\r
  79                         // First process positional arguments \r
  80                         //\r
  81                         \r
  82                         int i;\r
  83                         for (i = 0; i < pos_args.Count; i++) {\r
  84 \r
  85                                 Argument a = (Argument) pos_args [i];\r
  86 \r
  87                                 if (!a.Resolve (ec))\r
  88                                         return null;\r
  89 \r
  90                                 Expression e = Expression.Reduce (ec, a.Expr);\r
  91 \r
  92                                 if (e is Literal) \r
  93                                         pos_values [i] = ((Literal) e).GetValue ();\r
  94                                 else { \r
  95                                         error182 ();\r
  96                                         return null;\r
  97                                 }\r
  98                         }\r
  99 \r
 100                         //\r
 101                         // Now process named arguments\r
 102                         //\r
 103 \r
 104                         ArrayList field_infos = new ArrayList ();\r
 105                         ArrayList prop_infos  = new ArrayList ();\r
 106                         ArrayList field_values = new ArrayList ();\r
 107                         ArrayList prop_values = new ArrayList ();\r
 108 \r
 109                         for (i = 0; i < named_args.Count; i++) {\r
 110 \r
 111                                 DictionaryEntry de = (DictionaryEntry) named_args [i];\r
 112 \r
 113                                 string member_name = (string) de.Key;\r
 114                                 Argument a  = (Argument) de.Value;\r
 115 \r
 116                                 if (!a.Resolve (ec))\r
 117                                         return null;\r
 118 \r
 119                                 Expression member = Expression.MemberLookup (ec, attribute_type, member_name, false,\r
 120                                                                              MemberTypes.Field | MemberTypes.Property,\r
 121                                                                              BindingFlags.Public | BindingFlags.Instance,\r
 122                                                                              Location);\r
 123 \r
 124                                 if (member == null || !(member is PropertyExpr || member is FieldExpr)) {\r
 125                                         error617 (member_name);\r
 126                                         return null;\r
 127                                 }\r
 128 \r
 129                                 if (member is PropertyExpr) {\r
 130                                         PropertyExpr pe = (PropertyExpr) member;\r
 131                                         PropertyInfo pi = pe.PropertyInfo;\r
 132 \r
 133                                         if (!pi.CanWrite) {\r
 134                                                 error617 (member_name);\r
 135                                                 return null;\r
 136                                         }\r
 137 \r
 138                                         Expression e = Expression.Reduce (ec, a.Expr);\r
 139                                         \r
 140                                         if (e is Literal) \r
 141                                                 prop_values.Add (((Literal) e).GetValue ());\r
 142                                         else { \r
 143                                                 error182 ();\r
 144                                                 return null;\r
 145                                         }\r
 146                                         \r
 147                                         prop_infos.Add (pi);\r
 148                                         \r
 149                                 } else if (member is FieldExpr) {\r
 150                                         FieldExpr fe = (FieldExpr) member;\r
 151                                         FieldInfo fi = fe.FieldInfo;\r
 152 \r
 153                                         if (fi.IsInitOnly) {\r
 154                                                 error617 (member_name);\r
 155                                                 return null;\r
 156                                         }\r
 157 \r
 158                                         Expression e = Expression.Reduce (ec, a.Expr);\r
 159                                         \r
 160                                         if (e is Literal) \r
 161                                                 field_values.Add (((Literal) e).GetValue ());\r
 162                                         else { \r
 163                                                 error182 ();\r
 164                                                 return null;\r
 165                                         }\r
 166                                         \r
 167                                         field_infos.Add (fi);\r
 168                                 }\r
 169                         }\r
 170                         \r
 171                         Expression mg = Expression.MemberLookup (ec, attribute_type, ".ctor", false,\r
 172                                                                  MemberTypes.Constructor,\r
 173                                                                  BindingFlags.Public | BindingFlags.Instance,\r
 174                                                                  Location);\r
 175 \r
 176                         if (mg == null) {\r
 177                                 Report.Error (-6, Location, "Could not find a constructor for this argument list.");\r
 178                                 return null;\r
 179                         }\r
 180 \r
 181                         MethodBase constructor = Invocation.OverloadResolve (ec, (MethodGroupExpr) mg, pos_args, Location);\r
 182 \r
 183                         if (constructor == null) {\r
 184                                 Report.Error (-6, Location, "Could not find a constructor for this argument list.");\r
 185                                 return null;\r
 186                         }\r
 187                         \r
 188                         PropertyInfo [] prop_info_arr = new PropertyInfo [prop_infos.Count];\r
 189                         FieldInfo [] field_info_arr = new FieldInfo [field_infos.Count];\r
 190                         object [] field_values_arr = new object [field_values.Count];\r
 191                         object [] prop_values_arr = new object [prop_values.Count];\r
 192 \r
 193                         field_infos.CopyTo  (field_info_arr, 0);\r
 194                         field_values.CopyTo (field_values_arr, 0);\r
 195 \r
 196                         prop_values.CopyTo  (prop_values_arr, 0);\r
 197                         prop_infos.CopyTo   (prop_info_arr, 0);\r
 198                         \r
 199                         CustomAttributeBuilder cb = new CustomAttributeBuilder ((ConstructorInfo) constructor, pos_values,\r
 200                                                                                 prop_info_arr, prop_values_arr,\r
 201                                                                                 field_info_arr, field_values_arr); \r
 202                         \r
 203                         return cb;\r
 204                 }\r
 205 \r
 206         }\r
 207         \r
 208         public class AttributeSection {\r
 209                 \r
 210                 public readonly string    Target;\r
 211                 public readonly ArrayList Attributes;\r
 212                 \r
 213                 public AttributeSection (string target, ArrayList attrs)\r
 214                 {\r
 215                         Target = target;\r
 216                         Attributes = attrs;\r
 217                 }\r
 218                 \r
 219         }\r
 220 \r
 221         public class Attributes {\r
 222 \r
 223                 public ArrayList AttributeSections;\r
 224 \r
 225                 public Attributes (AttributeSection a)\r
 226                 {\r
 227                         AttributeSections = new ArrayList ();\r
 228                         AttributeSections.Add (a);\r
 229 \r
 230                 }\r
 231 \r
 232                 public void AddAttribute (AttributeSection a)\r
 233                 {\r
 234                         if (a != null)\r
 235                                 AttributeSections.Add (a);\r
 236                 }\r
 237                 \r
 238         }\r
 239 }\r