mcs/ilasm/scanner/NumberHelper.cs

   1 // NumberHelper.cs\r
   2 // Author: Sergey Chaban (serge@wildwestsoftware.com)\r
   3 \r
   4 using System;\r
   5 using System.Text;\r
   6 using System.Globalization;\r
   7 \r
   8 namespace Mono.ILASM {\r
   9 \r
  10         /// <summary>\r
  11         /// </summary>\r
  12         internal class NumberHelper : StringHelperBase {\r
  13 \r
  14                 private ILToken result;\r
  15 \r
  16                 /// <summary>\r
  17                 /// </summary>\r
  18                 /// <param name="host"></param>\r
  19                 public NumberHelper (ILTokenizer host) : base (host)\r
  20                 {\r
  21                         Reset ();\r
  22                 }\r
  23 \r
  24 \r
  25                 private void Reset ()\r
  26                 {\r
  27                         result = ILToken.Invalid.Clone() as ILToken;\r
  28                 }\r
  29 \r
  30                 /// <summary>\r
  31                 /// </summary>\r
  32                 /// <returns></returns>\r
  33                 public override bool Start (char ch)\r
  34                 {\r
  35                         bool res = (Char.IsDigit (ch) || ch == '-' || (ch == '.' && Char.IsDigit ((char) host.Reader.Peek ())));\r
  36                         Reset ();\r
  37                         return res;\r
  38                 }\r
  39 \r
  40                 bool is_hex (int e)\r
  41                 {\r
  42                         return (e >= '0' && e <= '9') || (e >= 'A' && e <= 'F') || (e >= 'a' && e <= 'f');\r
  43                 }\r
  44 \r
  45                 bool is_sign (int ch)\r
  46                 {\r
  47                         return ((ch == '+') || (ch == '-'));\r
  48                 }\r
  49 \r
  50                 bool is_e (int ch)\r
  51                 {\r
  52                         return ((ch == 'e') || (ch == 'E'));\r
  53                 }\r
  54 \r
  55                 /// <summary>\r
  56                 /// </summary>\r
  57                 /// <returns></returns>\r
  58                 public override string Build ()\r
  59                 {\r
  60                         ILReader reader = host.Reader;\r
  61                         reader.MarkLocation ();\r
  62                         StringBuilder num_builder = new StringBuilder ();\r
  63                         string num;\r
  64                         int ch;\r
  65                         int peek;\r
  66                         bool is_real = false;\r
  67                         bool dec_found = false;\r
  68 \r
  69                         NumberStyles nstyles = NumberStyles.AllowExponent | NumberStyles.AllowDecimalPoint |\r
  70                                 NumberStyles.AllowLeadingSign;\r
  71 \r
  72                         ch = reader.Read ();\r
  73                         peek = reader.Peek ();\r
  74                         reader.Unread (ch);\r
  75 \r
  76                         if (ch == '0' && (peek == 'x' || peek == 'X'))\r
  77                                 return BuildHex ();\r
  78 \r
  79                         if (is_sign (reader.Peek ()))\r
  80                                 num_builder.Append ((char) reader.Read ());\r
  81 \r
  82                         do {\r
  83                                 ch = reader.Read ();\r
  84                                 peek = reader.Peek ();\r
  85                                 num_builder.Append ((char) ch);\r
  86 \r
  87                                 if (is_e (ch)) {\r
  88                                         if (is_real)\r
  89                                                 throw new ILTokenizingException (reader.Location, num_builder.ToString ());\r
  90 \r
  91                                         is_real = true;\r
  92                                 }\r
  93                                 if (ch == '.')\r
  94                                         dec_found = true;\r
  95                                 if (!is_hex(peek) &&\r
  96                                     !(peek == '.' && !dec_found) && !is_e (peek) &&\r
  97                                     !(is_sign (peek) && is_real)) {\r
  98                                         break;\r
  99                                 }\r
 100                         } while (ch != -1);\r
 101 \r
 102                         num = num_builder.ToString ();\r
 103 \r
 104                         // Check for hexbytes\r
 105                         if (num.Length == 2) {\r
 106                                 if (Char.IsLetter (num[0]) || Char.IsLetter (num[1])) {\r
 107                                         result.token = Token.HEXBYTE;\r
 108                                         result.val = Byte.Parse (num, NumberStyles.HexNumber);\r
 109                                         return num;\r
 110                                 }\r
 111                         }\r
 112 \r
 113                         if (ch == '.' && peek == '.') {\r
 114                                 num = num.Substring (0, num.Length-1);\r
 115                                 reader.Unread ('.');\r
 116                         } else if (ch == '.') {\r
 117                                 num += '0';\r
 118                         }\r
 119 \r
 120                         try {\r
 121                                 if (dec_found || is_real) {\r
 122                                         double d = Double.Parse (num, nstyles, NumberFormatInfo.InvariantInfo);\r
 123                                         result.token = Token.FLOAT64;\r
 124                                         result.val = d;\r
 125                                 } else {\r
 126                                         long i = Int64.Parse (num, nstyles);\r
 127                                         // if (i < Int32.MinValue || i > Int32.MaxValue) {\r
 128                                                 result.token = Token.INT64;\r
 129                                                 result.val = i;\r
 130                                         // } else {\r
 131                                         //        result.token = Token.INT32;\r
 132                                         //        result.val = (int) i;\r
 133                                         // }\r
 134                                 }\r
 135                         } catch {\r
 136                                 reader.Unread (num.ToCharArray ());\r
 137                                 reader.RestoreLocation ();\r
 138                                 num = String.Empty;\r
 139                                 Reset ();\r
 140                                 throw new ILTokenizingException (reader.Location, num_builder.ToString ());\r
 141                         }\r
 142                         return num;\r
 143                 }\r
 144 \r
 145                 public string BuildHex ()\r
 146                 {\r
 147                         ILReader reader = host.Reader;\r
 148                         reader.MarkLocation ();\r
 149                         StringBuilder num_builder = new StringBuilder ();\r
 150                         NumberStyles nstyles = NumberStyles.HexNumber;\r
 151 \r
 152                         string num;\r
 153                         int ch;\r
 154                         int peek;\r
 155 \r
 156                         ch = reader.Read ();\r
 157                         if (ch != '0')\r
 158                                 throw new ILTokenizingException (reader.Location, ((char) ch).ToString ());\r
 159 \r
 160                         ch = reader.Read ();\r
 161 \r
 162                         if (ch != 'x' && ch != 'X')\r
 163                                 throw new ILTokenizingException (reader.Location, "0" + (char) ch);\r
 164 \r
 165                         do {\r
 166                                 ch = reader.Read ();\r
 167                                 peek = reader.Peek ();\r
 168                                 num_builder.Append ((char) ch);\r
 169 \r
 170                                 if (!is_hex ((char) peek))\r
 171                                         break;\r
 172 \r
 173                                 if (num_builder.Length == 32)\r
 174                                         throw new ILTokenizingException (reader.Location, num_builder.ToString ());\r
 175 \r
 176                         } while (ch != -1);\r
 177 \r
 178                         num = num_builder.ToString ();\r
 179 \r
 180                         try {\r
 181                                 long i = (long) UInt64.Parse (num, nstyles);\r
 182                                 //if (i < Int32.MinValue || i > Int32.MaxValue) {\r
 183                                         result.token = Token.INT64;\r
 184                                         result.val = i;\r
 185                                 //} else {\r
 186                                 //        result.token = Token.INT32;\r
 187                                 //        result.val = (int) i;\r
 188                                 //}\r
 189                         } catch {\r
 190                                 string tnum = num;\r
 191                                 reader.Unread (num.ToCharArray ());\r
 192                                 reader.RestoreLocation ();\r
 193                                 num = String.Empty;\r
 194                                 Reset ();\r
 195                                 throw new ILTokenizingException (reader.Location, tnum);\r
 196                         }\r
 197                         return num;\r
 198                 }\r
 199 \r
 200                 /// <summary>\r
 201                 /// </summary>\r
 202                 public ILToken ResultToken {\r
 203                         get {\r
 204                                 return result;\r
 205                         }\r
 206                 }\r
 207 \r
 208 \r
 209         }\r
 210 \r
 211 }\r