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