mcs/gmcs/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                 public const int METHOD_GENERIC = 0x10000;
  37
  38                 public const int Accessibility =
  39                         PUBLIC | PROTECTED | INTERNAL | PRIVATE;
  40                 public const int AllowedExplicitImplFlags =
  41                         UNSAFE | EXTERN;
  42
  43                 static public string Name (int i)
  44                 {
  45                         string s = "";
  46
  47                         switch (i) {
  48                         case Modifiers.NEW:
  49                                 s = "new"; break;
  50                         case Modifiers.PUBLIC:
  51                                 s = "public"; break;
  52                         case Modifiers.PROTECTED:
  53                                 s = "protected"; break;
  54                         case Modifiers.INTERNAL:
  55                                 s = "internal"; break;
  56                         case Modifiers.PRIVATE:
  57                                 s = "private"; break;
  58                         case Modifiers.ABSTRACT:
  59                                 s = "abstract"; break;
  60                         case Modifiers.SEALED:
  61                                 s = "sealed"; break;
  62                         case Modifiers.STATIC:
  63                                 s = "static"; break;
  64                         case Modifiers.READONLY:
  65                                 s = "readonly"; break;
  66                         case Modifiers.VIRTUAL:
  67                                 s = "virtual"; break;
  68                         case Modifiers.OVERRIDE:
  69                                 s = "override"; break;
  70                         case Modifiers.EXTERN:
  71                                 s = "extern"; break;
  72                         case Modifiers.VOLATILE:
  73                                 s = "volatile"; break;
  74                         case Modifiers.UNSAFE:
  75                                 s = "unsafe"; break;
  76                         }
  77
  78                         return s;
  79                 }
  80
  81                 public static string GetDescription (MethodAttributes ma)
  82                 {
  83                         if ((ma & MethodAttributes.Assembly) != 0)
  84                                 return "internal";
  85
  86                         if ((ma & MethodAttributes.Family) != 0)
  87                                 return "protected";
  88
  89                         if ((ma & MethodAttributes.Public) != 0)
  90                                 return "public";
  91
  92                         if ((ma & MethodAttributes.FamANDAssem) != 0)
  93                                 return "protected internal";
  94
  95                         if ((ma & MethodAttributes.Private) != 0)
  96                                 return "private";
  97
  98                         throw new NotImplementedException (ma.ToString ());
  99                 }
 100
 101                 public static TypeAttributes TypeAttr (int mod_flags, bool is_toplevel)
 102                 {
 103                         TypeAttributes t = 0;
 104
 105                         if (is_toplevel){
 106                                 if ((mod_flags & PUBLIC) != 0)
 107                                         t |= TypeAttributes.Public;
 108                                 if ((mod_flags & PRIVATE) != 0)
 109                                         t |= TypeAttributes.NotPublic;
 110                         } else {
 111                                 if ((mod_flags & PUBLIC) != 0)
 112                                         t |= TypeAttributes.NestedPublic;
 113                                 if ((mod_flags & PRIVATE) != 0)
 114                                         t |= TypeAttributes.NestedPrivate;
 115                                 if ((mod_flags & PROTECTED) != 0 && (mod_flags & INTERNAL) != 0)
 116                                         t |= TypeAttributes.NestedFamORAssem;
 117                                 if ((mod_flags & PROTECTED) != 0)
 118                                         t |= TypeAttributes.NestedFamily;
 119                                 if ((mod_flags & INTERNAL) != 0)
 120                                         t |= TypeAttributes.NestedAssembly;
 121                         }
 122
 123                         if ((mod_flags & SEALED) != 0)
 124                                 t |= TypeAttributes.Sealed;
 125                         if ((mod_flags & ABSTRACT) != 0)
 126                                 t |= TypeAttributes.Abstract;
 127
 128                         return t;
 129                 }
 130
 131                 public static TypeAttributes TypeAttr (int mod_flags, TypeContainer caller)
 132                 {
 133                         TypeAttributes t = TypeAttr (mod_flags, caller.IsTopLevel);
 134
 135                         // If we do not have static constructors, static methods
 136                         // can be invoked without initializing the type.
 137                         if (!caller.UserDefinedStaticConstructor &&
 138                             (caller.Kind != Kind.Interface))
 139                                 t |= TypeAttributes.BeforeFieldInit;
 140
 141                         return t;
 142                 }
 143
 144                 public static FieldAttributes FieldAttr (int mod_flags)
 145                 {
 146                         FieldAttributes fa = 0;
 147
 148                         if ((mod_flags & PUBLIC) != 0)
 149                                 fa |= FieldAttributes.Public;
 150                         if ((mod_flags & PRIVATE) != 0)
 151                                 fa |= FieldAttributes.Private;
 152                         if ((mod_flags & PROTECTED) != 0){
 153                                 if ((mod_flags & INTERNAL) != 0)
 154                                         fa |= FieldAttributes.FamORAssem;
 155                                 else
 156                                         fa |= FieldAttributes.Family;
 157                         } else {
 158                                 if ((mod_flags & INTERNAL) != 0)
 159                                         fa |= FieldAttributes.Assembly;
 160                         }
 161
 162                         if ((mod_flags & STATIC) != 0)
 163                                 fa |= FieldAttributes.Static;
 164                         if ((mod_flags & READONLY) != 0)
 165                                 fa |= FieldAttributes.InitOnly;
 166
 167                         return fa;
 168                 }
 169
 170                 public static MethodAttributes MethodAttr (int mod_flags)
 171                 {
 172                         MethodAttributes ma = MethodAttributes.HideBySig;
 173
 174                         if ((mod_flags & PUBLIC) != 0)
 175                                 ma |= MethodAttributes.Public;
 176                         if ((mod_flags & PRIVATE) != 0)
 177                                 ma |= MethodAttributes.Private;
 178                         if ((mod_flags & PROTECTED) != 0){
 179                                 if ((mod_flags & INTERNAL) != 0)
 180                                         ma |= MethodAttributes.FamORAssem;
 181                                 else
 182                                         ma |= MethodAttributes.Family;
 183                         } else {
 184                                 if ((mod_flags & INTERNAL) != 0)
 185                                         ma |= MethodAttributes.Assembly;
 186                         }
 187
 188                         if ((mod_flags & STATIC) != 0)
 189                                 ma |= MethodAttributes.Static;
 190                         if ((mod_flags & ABSTRACT) != 0){
 191                                 ma |= MethodAttributes.Abstract | MethodAttributes.Virtual;
 192                         }
 193                         if ((mod_flags & SEALED) != 0)
 194                                 ma |= MethodAttributes.Final;
 195
 196                         if ((mod_flags & VIRTUAL) != 0)
 197                                 ma |= MethodAttributes.Virtual;
 198
 199                         if ((mod_flags & OVERRIDE) != 0)
 200                                 ma |= MethodAttributes.Virtual;
 201                         else {
 202                                 if ((ma & MethodAttributes.Virtual) != 0)
 203                                         ma |= MethodAttributes.NewSlot;
 204                         }
 205
 206                         return ma;
 207                 }
 208
 209                 // <summary>
 210                 //   Checks the object @mod modifiers to be in @allowed.
 211                 //   Returns the new mask.  Side effect: reports any
 212                 //   incorrect attributes.
 213                 // </summary>
 214                 public static int Check (int allowed, int mod, int def_access, Location l)
 215                 {
 216                         int invalid_flags  = (~allowed) & mod;
 217                         int i;
 218
 219                         if (invalid_flags == 0){
 220                                 int a = mod;
 221
 222                                 if ((mod & Modifiers.UNSAFE) != 0){
 223                                         RootContext.CheckUnsafeOption (l);
 224                                 }
 225
 226                                 //
 227                                 // If no accessibility bits provided
 228                                 // then provide the defaults.
 229                                 //
 230                                 if ((mod & Accessibility) == 0){
 231                                         mod |= def_access;
 232                                         return mod;
 233                                 }
 234
 235                                 //
 236                                 // Make sure that no conflicting accessibility
 237                                 // bits have been set.  Protected+Internal is
 238                                 // allowed, that is why they are placed on bits
 239                                 // 1 and 4 (so the shift 3 basically merges them)
 240                                 //
 241                                 a &= 15;
 242                                 a |= (a >> 3);
 243                                 a = ((a & 2) >> 1) + (a & 5);
 244                                 a = ((a & 4) >> 2) + (a & 3);
 245                                 if (a > 1)
 246                                         Report.Error (107, l, "More than one protection modifier specified");
 247
 248                                 return mod;
 249                         }
 250
 251                         for (i = 1; i <= TOP; i <<= 1){
 252                                 if ((i & invalid_flags) == 0)
 253                                         continue;
 254
 255                                 Error_InvalidModifier (l, Name (i));
 256                         }
 257
 258                         return allowed & mod;
 259                 }
 260
 261                 public static void Error_InvalidModifier (Location l, string name)
 262                 {
 263                         Report.Error (106, l, "The modifier `" + name + "' is not valid for this item");
 264                 }
 265         }
 266 }