mcs/class/corlib/System.Reflection.Emit/CustomAttributeBuilder.cs

   1
   2 //
   3 // System.Reflection.Emit/CustomAttributeBuilder.cs
   4 //
   5 // Author:
   6 //   Paolo Molaro (lupus@ximian.com)
   7 //
   8 // (C) 2001 Ximian, Inc.  http://www.ximian.com
   9 //
  10
  11 using System;
  12 using System.Reflection;
  13 using System.Reflection.Emit;
  14 using System.Runtime.CompilerServices;
  15 using System.Runtime.InteropServices;
  16
  17 namespace System.Reflection.Emit {
  18         public class CustomAttributeBuilder {
  19                 ConstructorInfo ctor;
  20                 byte[] data;
  21
  22                 internal ConstructorInfo Ctor {
  23                         get {return ctor;}
  24                 }
  25
  26                 internal byte[] Data {
  27                         get {return data;}
  28                 }
  29
  30                 [MethodImplAttribute(MethodImplOptions.InternalCall)]
  31                 static extern byte[] GetBlob(ConstructorInfo con, object[] constructorArgs, PropertyInfo[] namedProperties, object[] propertyValues, FieldInfo[] namedFields, object[] fieldValues);
  32
  33                 internal CustomAttributeBuilder( ConstructorInfo con, byte[] cdata) {
  34                         ctor = con;
  35                         data = (byte[])cdata.Clone ();
  36                         /* should we check that the user supplied data is correct? */
  37                 }
  38
  39                 public CustomAttributeBuilder( ConstructorInfo con, object[] constructorArgs)
  40                         : this (con, constructorArgs, null, null, null, null) {
  41                 }
  42                 public CustomAttributeBuilder( ConstructorInfo con, object[] constructorArgs, FieldInfo[] namedFields, object[] fieldValues)
  43                         : this (con, constructorArgs, null, null, namedFields, fieldValues) {
  44                 }
  45                 public CustomAttributeBuilder( ConstructorInfo con, object[] constructorArgs, PropertyInfo[] namedProperties, object[] propertyValues)
  46                         : this (con, constructorArgs, namedProperties, propertyValues, null, null) {
  47                 }
  48                 public CustomAttributeBuilder( ConstructorInfo con, object[] constructorArgs, PropertyInfo[] namedProperties, object[] propertyValues, FieldInfo[] namedFields, object[] fieldValues) {
  49                         ctor = con;
  50                         data = GetBlob (con, constructorArgs, namedProperties, propertyValues, namedFields, fieldValues);
  51                 }
  52
  53                 /* helper methods */
  54                 internal static int decode_len (byte[] data, int pos, out int rpos) {
  55                         int len = 0;
  56                         if ((data [pos] & 0x80) == 0) {
  57                                 len = (int)(data [pos++] & 0x7f);
  58                         } else if ((data [pos] & 0x40) == 0) {
  59                                 len = ((data [pos] & 0x3f) << 8) + data [pos + 1];
  60                                 pos += 2;
  61                         } else {
  62                                 len = ((data [pos] & 0x1f) << 24) + (data [pos + 1] << 16) + (data [pos + 2] << 8) + data [pos + 3];
  63                                 pos += 4;
  64                         }
  65                         rpos = pos;
  66                         return len;
  67                 }
  68
  69                 internal static string string_from_bytes (byte[] data, int pos, int len) {
  70                         char[] chars = new char [len];
  71                         // FIXME: use a utf8 decoder here
  72                         for (int i = 0; i < len; ++i)
  73                                 chars [i] = (char)data [pos + i];
  74                         return new String (chars);
  75                 }
  76
  77                 internal static UnmanagedMarshal get_umarshal (CustomAttributeBuilder customBuilder, bool is_field) {
  78                         byte[] data = customBuilder.Data;
  79                         UnmanagedType subtype = UnmanagedType.I4;
  80                         int value;
  81                         int utype; /* the (stupid) ctor takes a short or an enum ... */
  82                         utype = (int)data [2];
  83                         utype |= ((int)data [3]) << 8;
  84
  85                         string first_type_name = customBuilder.Ctor.GetParameters()[0].ParameterType.FullName;
  86                         int pos = 6;
  87                         if (first_type_name == "System.Int16")
  88                                 pos = 4;
  89                         int nnamed = (int)data [pos++];
  90                         nnamed |= ((int)data [pos++]) << 8;
  91
  92                         for (int i = 0; i < nnamed; ++i) {
  93                                 byte type = data [pos++];
  94                                 int len = decode_len (data, pos, out pos);
  95                                 string named_name = string_from_bytes (data, pos, len);
  96                                 pos += len;
  97                                 switch (named_name) {
  98                                 case "ArraySubType":
  99                                         value = (int)data [pos++];
 100                                         value |= ((int)data [pos++]) << 8;
 101                                         value |= ((int)data [pos++]) << 16;
 102                                         value |= ((int)data [pos++]) << 24;
 103                                         subtype = (UnmanagedType)value;
 104                                         break;
 105                                 default:
 106                                         break;
 107                                 }
 108                         }
 109
 110                         switch ((UnmanagedType)utype) {
 111                         case UnmanagedType.LPArray:
 112                                 return UnmanagedMarshal.DefineLPArray (subtype);
 113                         case UnmanagedType.SafeArray:
 114                                 return UnmanagedMarshal.DefineSafeArray (subtype);
 115                         case UnmanagedType.ByValArray:
 116                         case UnmanagedType.ByValTStr:
 117                         default:
 118                                 return UnmanagedMarshal.DefineUnmanagedMarshal ((UnmanagedType)utype);
 119                         }
 120                 }
 121
 122         }
 123 }