class/corlib/System/Buffer.cs

   1 //
   2 // System.Buffer.cs
   3 //
   4 // Authors:
   5 //   Paolo Molaro (lupus@ximian.com)
   6 //   Dan Lewis (dihlewis@yahoo.co.uk)
   7 //
   8 // (C) 2001 Ximian, Inc.  http://www.ximian.com
   9 //
  10
  11 //
  12 // Copyright (C) 2004 Novell, Inc (http://www.novell.com)
  13 //
  14 // Permission is hereby granted, free of charge, to any person obtaining
  15 // a copy of this software and associated documentation files (the
  16 // "Software"), to deal in the Software without restriction, including
  17 // without limitation the rights to use, copy, modify, merge, publish,
  18 // distribute, sublicense, and/or sell copies of the Software, and to
  19 // permit persons to whom the Software is furnished to do so, subject to
  20 // the following conditions:
  21 //
  22 // The above copyright notice and this permission notice shall be
  23 // included in all copies or substantial portions of the Software.
  24 //
  25 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  26 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  27 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  28 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  29 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  30 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  31 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  32 //
  33
  34 using System.Runtime.CompilerServices;
  35 using System.Runtime.InteropServices;
  36
  37 namespace System {
  38         [ComVisible (true)]
  39         public static class Buffer {
  40
  41                 public static int ByteLength (Array array)
  42                 {
  43                         // note: the other methods in this class also use ByteLength to test for
  44                         // null and non-primitive arguments as a side-effect.
  45
  46                         if (array == null)
  47                                 throw new ArgumentNullException ("array");
  48
  49                         int length = ByteLengthInternal (array);
  50                         if (length < 0)
  51                                 throw new ArgumentException (Locale.GetText ("Object must be an array of primitives."));
  52
  53                         return length;
  54                 }
  55
  56                 public static byte GetByte (Array array, int index)
  57                 {
  58                         if (index < 0 || index >= ByteLength (array))
  59                                 throw new ArgumentOutOfRangeException ("index", Locale.GetText(
  60                                         "Value must be non-negative and less than the size of the collection."));
  61
  62                         return GetByteInternal (array, index);
  63                 }
  64
  65                 public static void SetByte (Array array, int index, byte value)
  66                 {
  67                         if (index < 0 || index >= ByteLength (array))
  68                                 throw new ArgumentOutOfRangeException ("index", Locale.GetText(
  69                                         "Value must be non-negative and less than the size of the collection."));
  70
  71                         SetByteInternal (array, index, value);
  72                 }
  73
  74                 public static void BlockCopy (Array src, int srcOffset, Array dst, int dstOffset, int count)
  75                 {
  76                         if (src == null)
  77                                 throw new ArgumentNullException ("src");
  78
  79                         if (dst == null)
  80                                 throw new ArgumentNullException ("dst");
  81
  82                         if (srcOffset < 0)
  83                                 throw new ArgumentOutOfRangeException ("srcOffset", Locale.GetText(
  84                                         "Non-negative number required."));
  85
  86                         if (dstOffset < 0)
  87                                 throw new ArgumentOutOfRangeException ("dstOffset", Locale.GetText (
  88                                         "Non-negative number required."));
  89
  90                         if (count < 0)
  91                                 throw new ArgumentOutOfRangeException ("count", Locale.GetText (
  92                                         "Non-negative number required."));
  93
  94                         // We do the checks in unmanaged code for performance reasons
  95                         bool res = BlockCopyInternal (src, srcOffset, dst, dstOffset, count);
  96                         if (!res) {
  97                                 // watch for integer overflow
  98                                 if ((srcOffset > ByteLength (src) - count) || (dstOffset > ByteLength (dst) - count))
  99                                         throw new ArgumentException (Locale.GetText (
 100                                                 "Offset and length were out of bounds for the array or count is greater than " +
 101                                                 "the number of elements from index to the end of the source collection."));
 102                         }
 103                 }
 104
 105                 // private
 106                 [MethodImplAttribute (MethodImplOptions.InternalCall)]
 107                 private extern static int ByteLengthInternal (Array array);
 108
 109                 [MethodImplAttribute (MethodImplOptions.InternalCall)]
 110                 private extern static byte GetByteInternal (Array array, int index);
 111
 112                 [MethodImplAttribute (MethodImplOptions.InternalCall)]
 113                 private extern static void SetByteInternal (Array array, int index, int value);
 114
 115                 [MethodImplAttribute (MethodImplOptions.InternalCall)]
 116                 internal extern static bool BlockCopyInternal (Array src, int src_offset, Array dest, int dest_offset, int count);
 117         }
 118 }