mcs/modifiers.cs

   1 //
   2 // modifiers.cs: Modifier handling.
   3 //
   4 using System;
   5 using System.Reflection;
   6
   7 namespace Mono.CSharp
   8 {
   9         [Flags]
  10         public enum Modifiers
  11         {
  12                 //
  13                 // The ordering of the following 4 constants
  14                 // has been carefully done.
  15                 //
  16                 PROTECTED = 0x0001,
  17                 PUBLIC    = 0x0002,
  18                 PRIVATE   = 0x0004,
  19                 INTERNAL  = 0x0008,
  20                 NEW       = 0x0010,
  21                 ABSTRACT  = 0x0020,
  22                 SEALED    = 0x0040,
  23                 STATIC    = 0x0080,
  24                 READONLY  = 0x0100,
  25                 VIRTUAL   = 0x0200,
  26                 OVERRIDE  = 0x0400,
  27                 EXTERN    = 0x0800,
  28                 VOLATILE  = 0x1000,
  29                 UNSAFE    = 0x2000,
  30                 TOP       = 0x4000,
  31
  32                 //
  33                 // Compiler specific flags
  34                 //
  35                 PROPERTY_CUSTOM                 = 0x4000,
  36                 OVERRIDE_UNCHECKED              = 0x8000,
  37                 PARTIAL                                 = 0x20000,
  38                 DEFAULT_ACCESS_MODIFER  = 0x40000,
  39                 METHOD_EXTENSION                = 0x80000,
  40                 COMPILER_GENERATED              = 0x100000,
  41                 BACKING_FIELD                   = 0x200000,
  42                 DEBUGGER_HIDDEN                 = 0x400000,
  43
  44                 AccessibilityMask = PUBLIC | PROTECTED | INTERNAL | PRIVATE,
  45                 AllowedExplicitImplFlags = UNSAFE | EXTERN,
  46         }
  47
  48         static class ModifiersExtensions
  49         {
  50                 public static string AccessibilityName (Modifiers mod)
  51                 {
  52                         switch (mod & Modifiers.AccessibilityMask) {
  53                         case Modifiers.PUBLIC:
  54                                 return "public";
  55                         case Modifiers.PROTECTED:
  56                                 return "protected";
  57                         case Modifiers.PROTECTED | Modifiers.INTERNAL:
  58                                 return "protected internal";
  59                         case Modifiers.INTERNAL:
  60                                 return "internal";
  61                         case Modifiers.PRIVATE:
  62                                 return "private";
  63                         default:
  64                                 throw new NotImplementedException (mod.ToString ());
  65                         }
  66                 }
  67
  68                 static public string Name (Modifiers i)
  69                 {
  70                         string s = "";
  71
  72                         switch (i) {
  73                         case Modifiers.NEW:
  74                                 s = "new"; break;
  75                         case Modifiers.PUBLIC:
  76                                 s = "public"; break;
  77                         case Modifiers.PROTECTED:
  78                                 s = "protected"; break;
  79                         case Modifiers.INTERNAL:
  80                                 s = "internal"; break;
  81                         case Modifiers.PRIVATE:
  82                                 s = "private"; break;
  83                         case Modifiers.ABSTRACT:
  84                                 s = "abstract"; break;
  85                         case Modifiers.SEALED:
  86                                 s = "sealed"; break;
  87                         case Modifiers.STATIC:
  88                                 s = "static"; break;
  89                         case Modifiers.READONLY:
  90                                 s = "readonly"; break;
  91                         case Modifiers.VIRTUAL:
  92                                 s = "virtual"; break;
  93                         case Modifiers.OVERRIDE:
  94                                 s = "override"; break;
  95                         case Modifiers.EXTERN:
  96                                 s = "extern"; break;
  97                         case Modifiers.VOLATILE:
  98                                 s = "volatile"; break;
  99                         case Modifiers.UNSAFE:
 100                                 s = "unsafe"; break;
 101                         }
 102
 103                         return s;
 104                 }
 105
 106                 //
 107                 // Used by custom property accessors to check whether @modA is more restrictive than @modB
 108                 //
 109                 public static bool IsRestrictedModifier (Modifiers modA, Modifiers modB)
 110                 {
 111                         Modifiers flags = 0;
 112
 113                         if ((modB & Modifiers.PUBLIC) != 0) {
 114                                 flags = Modifiers.PROTECTED | Modifiers.INTERNAL | Modifiers.PRIVATE;
 115                         } else if ((modB & Modifiers.PROTECTED) != 0) {
 116                                 if ((modB & Modifiers.INTERNAL) != 0)
 117                                         flags = Modifiers.PROTECTED | Modifiers.INTERNAL;
 118
 119                                 flags |= Modifiers.PRIVATE;
 120                         } else if ((modB & Modifiers.INTERNAL) != 0)
 121                                 flags = Modifiers.PRIVATE;
 122
 123                         return modB != modA && (modA & (~flags)) == 0;
 124                 }
 125
 126                 public static TypeAttributes TypeAttr (Modifiers mod_flags, bool is_toplevel)
 127                 {
 128                         TypeAttributes t = 0;
 129
 130                         if (is_toplevel){
 131                                 if ((mod_flags & Modifiers.PUBLIC) != 0)
 132                                         t = TypeAttributes.Public;
 133                                 else if ((mod_flags & Modifiers.PRIVATE) != 0)
 134                                         t = TypeAttributes.NotPublic;
 135                         } else {
 136                                 if ((mod_flags & Modifiers.PUBLIC) != 0)
 137                                         t = TypeAttributes.NestedPublic;
 138                                 else if ((mod_flags & Modifiers.PRIVATE) != 0)
 139                                         t = TypeAttributes.NestedPrivate;
 140                                 else if ((mod_flags & (Modifiers.PROTECTED | Modifiers.INTERNAL)) == (Modifiers.PROTECTED | Modifiers.INTERNAL))
 141                                         t = TypeAttributes.NestedFamORAssem;
 142                                 else if ((mod_flags & Modifiers.PROTECTED) != 0)
 143                                         t = TypeAttributes.NestedFamily;
 144                                 else if ((mod_flags & Modifiers.INTERNAL) != 0)
 145                                         t = TypeAttributes.NestedAssembly;
 146                         }
 147
 148                         if ((mod_flags & Modifiers.SEALED) != 0)
 149                                 t |= TypeAttributes.Sealed;
 150                         if ((mod_flags & Modifiers.ABSTRACT) != 0)
 151                                 t |= TypeAttributes.Abstract;
 152
 153                         return t;
 154                 }
 155
 156                 public static FieldAttributes FieldAttr (Modifiers mod_flags)
 157                 {
 158                         FieldAttributes fa = 0;
 159
 160                         if ((mod_flags & Modifiers.PUBLIC) != 0)
 161                                 fa |= FieldAttributes.Public;
 162                         if ((mod_flags & Modifiers.PRIVATE) != 0)
 163                                 fa |= FieldAttributes.Private;
 164                         if ((mod_flags & Modifiers.PROTECTED) != 0) {
 165                                 if ((mod_flags & Modifiers.INTERNAL) != 0)
 166                                         fa |= FieldAttributes.FamORAssem;
 167                                 else
 168                                         fa |= FieldAttributes.Family;
 169                         } else {
 170                                 if ((mod_flags & Modifiers.INTERNAL) != 0)
 171                                         fa |= FieldAttributes.Assembly;
 172                         }
 173
 174                         if ((mod_flags & Modifiers.STATIC) != 0)
 175                                 fa |= FieldAttributes.Static;
 176                         if ((mod_flags & Modifiers.READONLY) != 0)
 177                                 fa |= FieldAttributes.InitOnly;
 178
 179                         return fa;
 180                 }
 181
 182                 public static MethodAttributes MethodAttr (Modifiers mod_flags)
 183                 {
 184                         MethodAttributes ma = MethodAttributes.HideBySig;
 185
 186                         switch (mod_flags & Modifiers.AccessibilityMask) {
 187                         case Modifiers.PUBLIC:
 188                                 ma |= MethodAttributes.Public;
 189                                 break;
 190                         case Modifiers.PRIVATE:
 191                                 ma |= MethodAttributes.Private;
 192                                 break;
 193                         case Modifiers.PROTECTED | Modifiers.INTERNAL:
 194                                 ma |= MethodAttributes.FamORAssem;
 195                                 break;
 196                         case Modifiers.PROTECTED:
 197                                 ma |= MethodAttributes.Family;
 198                                 break;
 199                         case Modifiers.INTERNAL:
 200                                 ma |= MethodAttributes.Assembly;
 201                                 break;
 202                         default:
 203                                 throw new NotImplementedException (mod_flags.ToString ());
 204                         }
 205
 206                         if ((mod_flags & Modifiers.STATIC) != 0)
 207                                 ma |= MethodAttributes.Static;
 208                         if ((mod_flags & Modifiers.ABSTRACT) != 0) {
 209                                 ma |= MethodAttributes.Abstract | MethodAttributes.Virtual;
 210                         }
 211                         if ((mod_flags & Modifiers.SEALED) != 0)
 212                                 ma |= MethodAttributes.Final;
 213
 214                         if ((mod_flags & Modifiers.VIRTUAL) != 0)
 215                                 ma |= MethodAttributes.Virtual;
 216
 217                         if ((mod_flags & Modifiers.OVERRIDE) != 0) {
 218                                 ma |= MethodAttributes.Virtual;
 219                         } else {
 220                                 if ((ma & MethodAttributes.Virtual) != 0)
 221                                         ma |= MethodAttributes.NewSlot;
 222                         }
 223
 224                         return ma;
 225                 }
 226
 227                 // <summary>
 228                 //   Checks the object @mod modifiers to be in @allowed.
 229                 //   Returns the new mask.  Side effect: reports any
 230                 //   incorrect attributes.
 231                 // </summary>
 232                 public static Modifiers Check (Modifiers allowed, Modifiers mod, Modifiers def_access, Location l, Report Report)
 233                 {
 234                         int invalid_flags = (~(int) allowed) & ((int) mod & ((int) Modifiers.TOP - 1));
 235                         int i;
 236
 237                         if (invalid_flags == 0){
 238
 239                                 if ((mod & Modifiers.UNSAFE) != 0){
 240                                         RootContext.CheckUnsafeOption (l, Report);
 241                                 }
 242
 243                                 //
 244                                 // If no accessibility bits provided
 245                                 // then provide the defaults.
 246                                 //
 247                                 if ((mod & Modifiers.AccessibilityMask) == 0) {
 248                                         mod |= def_access;
 249                                         if (def_access != 0)
 250                                                 mod |= Modifiers.DEFAULT_ACCESS_MODIFER;
 251                                         return mod;
 252                                 }
 253
 254                                 //
 255                                 // Make sure that no conflicting accessibility
 256                                 // bits have been set.  Protected+Internal is
 257                                 // allowed, that is why they are placed on bits
 258                                 // 1 and 4 (so the shift 3 basically merges them)
 259                                 //
 260                                 int a = (int) mod;
 261                                 a &= 15;
 262                                 a |= (a >> 3);
 263                                 a = ((a & 2) >> 1) + (a & 5);
 264                                 a = ((a & 4) >> 2) + (a & 3);
 265                                 if (a > 1)
 266                                         Report.Error (107, l, "More than one protection modifier specified");
 267
 268                                 return mod;
 269                         }
 270
 271                         for (i = 1; i <= (int) Modifiers.TOP; i <<= 1) {
 272                                 if ((i & invalid_flags) == 0)
 273                                         continue;
 274
 275                                 Error_InvalidModifier (l, Name ((Modifiers) i), Report);
 276                         }
 277
 278                         return allowed & mod;
 279                 }
 280
 281                 public static void Error_InvalidModifier (Location l, string name, Report Report)
 282                 {
 283                         Report.Error (106, l, "The modifier `{0}' is not valid for this item", name);
 284                 }
 285         }
 286 }