mcs/class/FirebirdSql.Data.Firebird/FirebirdSql.Data.Common/BinaryEncoding.cs

   1 /*\r
   2  *  BinaryEncoding handler for .Net.  This class implements\r
   3  *      a symmetric encoding that will convert string to byte[]\r
   4  *  and byte[] to string without any character set\r
   5  *  transliteration.\r
   6  *\r
   7  *  The contents of this file were written by jimb\r
   8  *  at connectedsw.com on Dec 9, 2004.  It is placed in\r
   9  *  the Public Domain and may be used as you see fit.\r
  10  */\r
  11 \r
  12 using System;\r
  13 using System.Text;\r
  14 \r
  15 namespace FirebirdSql.Data.Common\r
  16 {\r
  17         internal class BinaryEncoding : Encoding\r
  18         {\r
  19                 #region Static Methods\r
  20 \r
  21                 public static string BytesToString(byte[] byteArray)\r
  22                 {\r
  23                         // This code isn't great because it requires a double copy,\r
  24                         // but it requires unsafe code to solve the problem efficiently.\r
  25                         char[] charArray = new char[byteArray.GetLength(0)];\r
  26                         Array.Copy(byteArray, charArray, byteArray.Length);\r
  27 \r
  28                         return new string(charArray);\r
  29                 }\r
  30 \r
  31                 static void Validate(object data, int dataLength, int index, int count)\r
  32                 {\r
  33                         if (data == null)\r
  34                         {\r
  35                                 throw new ArgumentNullException();\r
  36                         }\r
  37 \r
  38                         if (index < 0 || count < 0 || dataLength - index < count)\r
  39                         {\r
  40                                 throw new ArgumentOutOfRangeException();\r
  41                         }\r
  42                 }\r
  43 \r
  44                 #endregion\r
  45 \r
  46                 #region Methods\r
  47 \r
  48                 public override int GetByteCount(char[] chars, int index, int count)\r
  49                 {\r
  50                         Validate(chars, chars.Length, index, count);\r
  51 \r
  52                         return count;\r
  53                 }\r
  54 \r
  55                 public override int GetByteCount(string chars)\r
  56                 {\r
  57                         return chars.Length;\r
  58                 }\r
  59 \r
  60                 public override int GetBytes(char[] chars, int charIndex, int charCount, byte[] bytes, int index)\r
  61                 {\r
  62                         Validate(chars, chars.Length, charIndex, charCount);\r
  63 \r
  64                         if (index < 0 || index > bytes.Length)\r
  65                         {\r
  66                                 throw new ArgumentOutOfRangeException();\r
  67                         }\r
  68                         if (bytes.Length - index < charCount)\r
  69                         {\r
  70                                 throw new ArgumentException();\r
  71                         }\r
  72 \r
  73                         int charEnd = charIndex + charCount;\r
  74                         while (charIndex < charEnd)\r
  75                         {\r
  76                                 bytes[index++] = (byte)chars[charIndex++];\r
  77                         }\r
  78 \r
  79                         return charCount;\r
  80                 }\r
  81 \r
  82                 public override int GetBytes(string chars, int charIndex, int charCount, byte[] bytes, int index)\r
  83                 {\r
  84                         Validate(chars, chars.Length, charIndex, charCount);\r
  85 \r
  86                         if (index < 0 || index > bytes.Length)\r
  87                         {\r
  88                                 throw new ArgumentOutOfRangeException();\r
  89                         }\r
  90                         if (bytes.Length - index < charCount)\r
  91                         {\r
  92                                 throw new ArgumentException();\r
  93                         }\r
  94 \r
  95                         int charEnd = charIndex + charCount;\r
  96                         while (charIndex < charEnd)\r
  97                         {\r
  98                                 bytes[index++] = (byte)chars[charIndex++];\r
  99                         }\r
 100 \r
 101                         return charCount;\r
 102                 }\r
 103 \r
 104                 public override int GetCharCount(byte[] bytes, int index, int count)\r
 105                 {\r
 106                         Validate(bytes, bytes.Length, index, count);\r
 107 \r
 108                         return (count);\r
 109                 }\r
 110 \r
 111                 public override int GetChars(byte[] bytes, int index, int count, char[] chars, int charIndex)\r
 112                 {\r
 113                         Validate(bytes, bytes.Length, index, count);\r
 114 \r
 115                         if (charIndex < 0 || charIndex > chars.Length)\r
 116                         {\r
 117                                 throw new ArgumentOutOfRangeException();\r
 118                         }\r
 119                         if (chars.Length - charIndex < count)\r
 120                         {\r
 121                                 throw new ArgumentException();\r
 122                         }\r
 123 \r
 124                         int byteEnd = index + count;\r
 125                         while (index < byteEnd)\r
 126                         {\r
 127                                 chars[charIndex++] = (char)bytes[index++];\r
 128                         }\r
 129 \r
 130                         return count;\r
 131                 }\r
 132 \r
 133 #if (!NETCF)\r
 134         \r
 135         public override string GetString(byte[] bytes)\r
 136                 {\r
 137                         return BytesToString(bytes);\r
 138                 }\r
 139 \r
 140 #endif\r
 141 \r
 142                 public override string GetString(byte[] bytes, int index, int count)\r
 143                 {\r
 144                         Validate(bytes, bytes.Length, index, count);\r
 145 \r
 146                         return BytesToString(bytes);\r
 147                 }\r
 148 \r
 149                 public override int GetMaxByteCount(int charCount)\r
 150                 {\r
 151                         return charCount;\r
 152                 }\r
 153 \r
 154                 public override int GetMaxCharCount(int count)\r
 155                 {\r
 156                         return count;\r
 157                 }\r
 158 \r
 159                 #endregion\r
 160         }\r
 161 }\r