mcs/mcs/modifiers.cs

   1 //
   2 // modifiers.cs: Modifier handling.
   3 //
   4 using System;
   5 using System.Reflection;
   6
   7 namespace Mono.CSharp {
   8         public class Modifiers {
   9
  10                 //
  11                 // The ordering of the following 4 constants
  12                 // has been carefully done.
  13                 //
  14                 public const int PROTECTED = 0x0001;
  15                 public const int PUBLIC    = 0x0002;
  16                 public const int PRIVATE   = 0x0004;
  17                 public const int INTERNAL  = 0x0008;
  18                 public const int NEW       = 0x0010;
  19                 public const int ABSTRACT  = 0x0020;
  20                 public const int SEALED    = 0x0040;
  21                 public const int STATIC    = 0x0080;
  22                 public const int READONLY  = 0x0100;
  23                 public const int VIRTUAL   = 0x0200;
  24                 public const int OVERRIDE  = 0x0400;
  25                 public const int EXTERN    = 0x0800;
  26                 public const int VOLATILE  = 0x1000;
  27                 public const int UNSAFE    = 0x2000;
  28                 public const int TOP       = 0x2000;
  29
  30                 public const int PROPERTY_CUSTOM = 0x4000; // Custom property modifier
  31
  32                 //
  33                 // We use this internally to flag that the method contains an iterator
  34                 //
  35                 public const int METHOD_YIELDS = 0x8000;
  36
  37                 public const int Accessibility =
  38                         PUBLIC | PROTECTED | INTERNAL | PRIVATE;
  39                 public const int AllowedExplicitImplFlags =
  40                         UNSAFE | EXTERN;
  41
  42                 static public string Name (int i)
  43                 {
  44                         string s = "";
  45
  46                         switch (i) {
  47                         case Modifiers.NEW:
  48                                 s = "new"; break;
  49                         case Modifiers.PUBLIC:
  50                                 s = "public"; break;
  51                         case Modifiers.PROTECTED:
  52                                 s = "protected"; break;
  53                         case Modifiers.INTERNAL:
  54                                 s = "internal"; break;
  55                         case Modifiers.PRIVATE:
  56                                 s = "private"; break;
  57                         case Modifiers.ABSTRACT:
  58                                 s = "abstract"; break;
  59                         case Modifiers.SEALED:
  60                                 s = "sealed"; break;
  61                         case Modifiers.STATIC:
  62                                 s = "static"; break;
  63                         case Modifiers.READONLY:
  64                                 s = "readonly"; break;
  65                         case Modifiers.VIRTUAL:
  66                                 s = "virtual"; break;
  67                         case Modifiers.OVERRIDE:
  68                                 s = "override"; break;
  69                         case Modifiers.EXTERN:
  70                                 s = "extern"; break;
  71                         case Modifiers.VOLATILE:
  72                                 s = "volatile"; break;
  73                         case Modifiers.UNSAFE:
  74                                 s = "unsafe"; break;
  75                         }
  76
  77                         return s;
  78                 }
  79
  80                 public static string GetDescription (MethodAttributes ma)
  81                 {
  82                         if ((ma & MethodAttributes.Assembly) != 0)
  83                                 return "internal";
  84
  85                         if ((ma & MethodAttributes.Family) != 0)
  86                                 return "protected";
  87
  88                         if ((ma & MethodAttributes.Public) != 0)
  89                                 return "public";
  90
  91                         if ((ma & MethodAttributes.FamANDAssem) != 0)
  92                                 return "protected internal";
  93
  94                         if ((ma & MethodAttributes.Private) != 0)
  95                                 return "private";
  96
  97                         throw new NotImplementedException (ma.ToString ());
  98                 }
  99
 100                 public static TypeAttributes TypeAttr (int mod_flags, bool is_toplevel)
 101                 {
 102                         TypeAttributes t = 0;
 103
 104                         if (is_toplevel){
 105                                 if ((mod_flags & PUBLIC) != 0)
 106                                         t |= TypeAttributes.Public;
 107                                 if ((mod_flags & PRIVATE) != 0)
 108                                         t |= TypeAttributes.NotPublic;
 109                         } else {
 110                                 if ((mod_flags & PUBLIC) != 0)
 111                                         t |= TypeAttributes.NestedPublic;
 112                                 if ((mod_flags & PRIVATE) != 0)
 113                                         t |= TypeAttributes.NestedPrivate;
 114                                 if ((mod_flags & PROTECTED) != 0 && (mod_flags & INTERNAL) != 0)
 115                                         t |= TypeAttributes.NestedFamORAssem;
 116                                 if ((mod_flags & PROTECTED) != 0)
 117                                         t |= TypeAttributes.NestedFamily;
 118                                 if ((mod_flags & INTERNAL) != 0)
 119                                         t |= TypeAttributes.NestedAssembly;
 120                         }
 121
 122                         if ((mod_flags & SEALED) != 0)
 123                                 t |= TypeAttributes.Sealed;
 124                         if ((mod_flags & ABSTRACT) != 0)
 125                                 t |= TypeAttributes.Abstract;
 126
 127                         return t;
 128                 }
 129
 130                 public static TypeAttributes TypeAttr (int mod_flags, TypeContainer caller)
 131                 {
 132                         TypeAttributes t = TypeAttr (mod_flags, caller.IsTopLevel);
 133
 134                         // If we do not have static constructors, static methods
 135                         // can be invoked without initializing the type.
 136                         if (!caller.UserDefinedStaticConstructor &&
 137                             (caller.Kind != Kind.Interface))
 138                                 t |= TypeAttributes.BeforeFieldInit;
 139
 140                         return t;
 141                 }
 142
 143                 public static FieldAttributes FieldAttr (int mod_flags)
 144                 {
 145                         FieldAttributes fa = 0;
 146
 147                         if ((mod_flags & PUBLIC) != 0)
 148                                 fa |= FieldAttributes.Public;
 149                         if ((mod_flags & PRIVATE) != 0)
 150                                 fa |= FieldAttributes.Private;
 151                         if ((mod_flags & PROTECTED) != 0){
 152                                 if ((mod_flags & INTERNAL) != 0)
 153                                         fa |= FieldAttributes.FamORAssem;
 154                                 else
 155                                         fa |= FieldAttributes.Family;
 156                         } else {
 157                                 if ((mod_flags & INTERNAL) != 0)
 158                                         fa |= FieldAttributes.Assembly;
 159                         }
 160
 161                         if ((mod_flags & STATIC) != 0)
 162                                 fa |= FieldAttributes.Static;
 163                         if ((mod_flags & READONLY) != 0)
 164                                 fa |= FieldAttributes.InitOnly;
 165
 166                         return fa;
 167                 }
 168
 169                 public static MethodAttributes MethodAttr (int mod_flags)
 170                 {
 171                         MethodAttributes ma = MethodAttributes.HideBySig;
 172
 173                         if ((mod_flags & PUBLIC) != 0)
 174                                 ma |= MethodAttributes.Public;
 175                         if ((mod_flags & PRIVATE) != 0)
 176                                 ma |= MethodAttributes.Private;
 177                         if ((mod_flags & PROTECTED) != 0){
 178                                 if ((mod_flags & INTERNAL) != 0)
 179                                         ma |= MethodAttributes.FamORAssem;
 180                                 else
 181                                         ma |= MethodAttributes.Family;
 182                         } else {
 183                                 if ((mod_flags & INTERNAL) != 0)
 184                                         ma |= MethodAttributes.Assembly;
 185                         }
 186
 187                         if ((mod_flags & STATIC) != 0)
 188                                 ma |= MethodAttributes.Static;
 189                         if ((mod_flags & ABSTRACT) != 0){
 190                                 ma |= MethodAttributes.Abstract | MethodAttributes.Virtual;
 191                         }
 192                         if ((mod_flags & SEALED) != 0)
 193                                 ma |= MethodAttributes.Final;
 194
 195                         if ((mod_flags & VIRTUAL) != 0)
 196                                 ma |= MethodAttributes.Virtual;
 197
 198                         if ((mod_flags & OVERRIDE) != 0)
 199                                 ma |= MethodAttributes.Virtual;
 200                         else {
 201                                 if ((ma & MethodAttributes.Virtual) != 0)
 202                                         ma |= MethodAttributes.NewSlot;
 203                         }
 204
 205                         return ma;
 206                 }
 207
 208                 // <summary>
 209                 //   Checks the object @mod modifiers to be in @allowed.
 210                 //   Returns the new mask.  Side effect: reports any
 211                 //   incorrect attributes.
 212                 // </summary>
 213                 public static int Check (int allowed, int mod, int def_access, Location l)
 214                 {
 215                         int invalid_flags  = (~allowed) & mod;
 216                         int i;
 217
 218                         if (invalid_flags == 0){
 219                                 int a = mod;
 220
 221                                 if ((mod & Modifiers.UNSAFE) != 0){
 222                                         RootContext.CheckUnsafeOption (l);
 223                                 }
 224
 225                                 //
 226                                 // If no accessibility bits provided
 227                                 // then provide the defaults.
 228                                 //
 229                                 if ((mod & Accessibility) == 0){
 230                                         mod |= def_access;
 231                                         return mod;
 232                                 }
 233
 234                                 //
 235                                 // Make sure that no conflicting accessibility
 236                                 // bits have been set.  Protected+Internal is
 237                                 // allowed, that is why they are placed on bits
 238                                 // 1 and 4 (so the shift 3 basically merges them)
 239                                 //
 240                                 a &= 15;
 241                                 a |= (a >> 3);
 242                                 a = ((a & 2) >> 1) + (a & 5);
 243                                 a = ((a & 4) >> 2) + (a & 3);
 244                                 if (a > 1)
 245                                         Report.Error (107, l, "More than one protection modifier specified");
 246
 247                                 return mod;
 248                         }
 249
 250                         for (i = 1; i <= TOP; i <<= 1){
 251                                 if ((i & invalid_flags) == 0)
 252                                         continue;
 253
 254                                 Error_InvalidModifier (l, Name (i));
 255                         }
 256
 257                         return allowed & mod;
 258                 }
 259
 260                 public static void Error_InvalidModifier (Location l, string name)
 261                 {
 262                         Report.Error (106, l, "The modifier `" + name + "' is not valid for this item");
 263                 }
 264         }
 265 }