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 Accessibility =
  31                         PUBLIC | PROTECTED | INTERNAL | PRIVATE;
  32
  33                 static public string Name (int i)
  34                 {
  35                         string s = "";
  36
  37                         switch (i) {
  38                         case Modifiers.NEW:
  39                                 s = "new"; break;
  40                         case Modifiers.PUBLIC:
  41                                 s = "public"; break;
  42                         case Modifiers.PROTECTED:
  43                                 s = "protected"; break;
  44                         case Modifiers.INTERNAL:
  45                                 s = "internal"; break;
  46                         case Modifiers.PRIVATE:
  47                                 s = "private"; break;
  48                         case Modifiers.ABSTRACT:
  49                                 s = "abstract"; break;
  50                         case Modifiers.SEALED:
  51                                 s = "sealed"; break;
  52                         case Modifiers.STATIC:
  53                                 s = "static"; break;
  54                         case Modifiers.READONLY:
  55                                 s = "readonly"; break;
  56                         case Modifiers.VIRTUAL:
  57                                 s = "virtual"; break;
  58                         case Modifiers.OVERRIDE:
  59                                 s = "override"; break;
  60                         case Modifiers.EXTERN:
  61                                 s = "extern"; break;
  62                         case Modifiers.VOLATILE:
  63                                 s = "volatile"; break;
  64                         }
  65
  66                         return s;
  67                 }
  68
  69                 public static TypeAttributes TypeAttr (int mod_flags, TypeContainer caller)
  70                 {
  71                         TypeAttributes t = 0;
  72                         bool top_level = caller.IsTopLevel;
  73
  74                         if (top_level){
  75                                 if ((mod_flags & PUBLIC) != 0)
  76                                         t |= TypeAttributes.Public;
  77                                 if ((mod_flags & PRIVATE) != 0)
  78                                         t |= TypeAttributes.NotPublic;
  79                         } else {
  80                                 if ((mod_flags & PUBLIC) != 0)
  81                                         t |= TypeAttributes.NestedPublic;
  82                                 if ((mod_flags & PRIVATE) != 0)
  83                                         t |= TypeAttributes.NestedPrivate;
  84                                 if ((mod_flags & PROTECTED) != 0 && (mod_flags & INTERNAL) != 0)
  85                                         t |= TypeAttributes.NestedFamORAssem;
  86                                 if ((mod_flags & PROTECTED) != 0)
  87                                         t |= TypeAttributes.NestedFamily;
  88                                 if ((mod_flags & INTERNAL) != 0)
  89                                         t |= TypeAttributes.NestedAssembly;
  90                         }
  91
  92                         if ((mod_flags & SEALED) != 0)
  93                                 t |= TypeAttributes.Sealed;
  94                         if ((mod_flags & ABSTRACT) != 0)
  95                                 t |= TypeAttributes.Abstract;
  96
  97                         // If we do not have static constructors, static methods
  98                         // can be invoked without initializing the type.
  99                         if (!caller.HaveStaticConstructor)
 100                                 t |= TypeAttributes.BeforeFieldInit;
 101
 102                         return t;
 103                 }
 104
 105                 public static FieldAttributes FieldAttr (int mod_flags)
 106                 {
 107                         FieldAttributes fa = 0;
 108
 109                         if ((mod_flags & PUBLIC) != 0)
 110                                 fa |= FieldAttributes.Public;
 111                         if ((mod_flags & PRIVATE) != 0)
 112                                 fa |= FieldAttributes.Private;
 113                         if ((mod_flags & PROTECTED) != 0 && (mod_flags & INTERNAL) != 0)
 114                                 fa |= FieldAttributes.FamORAssem;
 115                         if ((mod_flags & PROTECTED) != 0)
 116                                 fa |= FieldAttributes.Family;
 117                         if ((mod_flags & INTERNAL) != 0)
 118                                 fa |= FieldAttributes.Assembly;
 119
 120                         if ((mod_flags & STATIC) != 0)
 121                                 fa |= FieldAttributes.Static;
 122                         if ((mod_flags & READONLY) != 0)
 123                                 fa |= FieldAttributes.InitOnly;
 124
 125                         return fa;
 126                 }
 127
 128                 public static MethodAttributes MethodAttr (int mod_flags)
 129                 {
 130                         MethodAttributes ma = 0;
 131
 132                         if ((mod_flags & PUBLIC) != 0)
 133                                 ma |= MethodAttributes.Public;
 134                         if ((mod_flags & PRIVATE) != 0)
 135                                 ma |= MethodAttributes.Private;
 136                         if ((mod_flags & PROTECTED) != 0 && (mod_flags & INTERNAL) != 0)
 137                                 ma |= MethodAttributes.FamORAssem;
 138                         if ((mod_flags & PROTECTED) != 0)
 139                                 ma |= MethodAttributes.Family;
 140                         if ((mod_flags & INTERNAL) != 0)
 141                                 ma |= MethodAttributes.Assembly;
 142
 143
 144                         if ((mod_flags & STATIC) != 0)
 145                                 ma |= MethodAttributes.Static;
 146                         if ((mod_flags & ABSTRACT) != 0){
 147                                 ma |= MethodAttributes.Abstract | MethodAttributes.Virtual |
 148                                         MethodAttributes.HideBySig;
 149                         }
 150                         if ((mod_flags & SEALED) != 0)
 151                                 ma |= MethodAttributes.Final;
 152                         if ((mod_flags & VIRTUAL) != 0)
 153                                 ma |= MethodAttributes.Virtual;
 154
 155                         if ((mod_flags & OVERRIDE) != 0)
 156                                 ma |= MethodAttributes.Virtual | MethodAttributes.HideBySig;
 157                         else {
 158                                 if ((ma & MethodAttributes.Virtual) != 0)
 159                                         ma |= MethodAttributes.NewSlot;
 160                         }
 161
 162                         if ((mod_flags & NEW) != 0)
 163                                 ma |= MethodAttributes.HideBySig;
 164
 165                         return ma;
 166                 }
 167
 168                 // <summary>
 169                 //   Checks the object @mod modifiers to be in @allowed.
 170                 //   Returns the new mask.  Side effect: reports any
 171                 //   incorrect attributes.
 172                 // </summary>
 173                 public static int Check (int allowed, int mod, int def_access, Location l)
 174                 {
 175                         int invalid_flags  = (~allowed) & mod;
 176                         int i;
 177
 178                         if (invalid_flags == 0){
 179                                 int a = mod;
 180
 181                                 if ((mod & Modifiers.UNSAFE) != 0){
 182                                         if (!RootContext.Unsafe){
 183                                                 Report.Error (227, l,
 184                                                               "Unsafe code requires the --unsafe command " +
 185                                                               "line option to be specified");
 186                                         }
 187                                 }
 188
 189                                 //
 190                                 // If no accessibility bits provided
 191                                 // then provide the defaults.
 192                                 //
 193                                 if ((mod & Accessibility) == 0){
 194                                         mod |= def_access;
 195                                         return mod;
 196                                 }
 197
 198                                 //
 199                                 // Make sure that no conflicting accessibility
 200                                 // bits have been set.  Protected+Internal is
 201                                 // allowed, that is why they are placed on bits
 202                                 // 1 and 4 (so the shift 3 basically merges them)
 203                                 //
 204                                 a &= 15;
 205                                 a |= (a >> 3);
 206                                 a = ((a & 2) >> 1) + (a & 5);
 207                                 a = ((a & 4) >> 2) + (a & 3);
 208                                 if (a > 1)
 209                                         Report.Error (107, l, "More than one protection modifier specified");
 210
 211                                 return mod;
 212                         }
 213
 214                         for (i = 1; i < TOP; i <<= 1){
 215                                 if ((i & invalid_flags) == 0)
 216                                         continue;
 217
 218                                 Report.Error (106, l, "the modifier `" + Name (i) +
 219                                               "' is not valid for this item");
 220                         }
 221
 222                         return allowed & mod;
 223                 }
 224         }
 225 }