1 #region Copyright notice and license 2 // Protocol Buffers - Google's data interchange format 3 // Copyright 2008 Google Inc. All rights reserved. 4 // https://developers.google.com/protocol-buffers/ 5 // 6 // Redistribution and use in source and binary forms, with or without 7 // modification, are permitted provided that the following conditions are 8 // met: 9 // 10 // * Redistributions of source code must retain the above copyright 11 // notice, this list of conditions and the following disclaimer. 12 // * Redistributions in binary form must reproduce the above 13 // copyright notice, this list of conditions and the following disclaimer 14 // in the documentation and/or other materials provided with the 15 // distribution. 16 // * Neither the name of Google Inc. nor the names of its 17 // contributors may be used to endorse or promote products derived from 18 // this software without specific prior written permission. 19 // 20 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 21 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 22 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 23 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 24 // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 25 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 26 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 27 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 28 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 29 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 30 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 31 #endregion 32 33 using System; 34 35 namespace Google.Protobuf 36 { 37 /// <summary> 38 /// Provides a utility routine to copy small arrays much more quickly than Buffer.BlockCopy 39 /// </summary> 40 internal static class ByteArray 41 { 42 /// <summary> 43 /// The threshold above which you should use Buffer.BlockCopy rather than ByteArray.Copy 44 /// </summary> 45 private const int CopyThreshold = 12; 46 47 /// <summary> 48 /// Determines which copy routine to use based on the number of bytes to be copied. 49 /// </summary> Copy(byte[] src, int srcOffset, byte[] dst, int dstOffset, int count)50 internal static void Copy(byte[] src, int srcOffset, byte[] dst, int dstOffset, int count) 51 { 52 if (count > CopyThreshold) 53 { 54 Buffer.BlockCopy(src, srcOffset, dst, dstOffset, count); 55 } 56 else 57 { 58 int stop = srcOffset + count; 59 for (int i = srcOffset; i < stop; i++) 60 { 61 dst[dstOffset++] = src[i]; 62 } 63 } 64 } 65 66 /// <summary> 67 /// Reverses the order of bytes in the array 68 /// </summary> Reverse(byte[] bytes)69 internal static void Reverse(byte[] bytes) 70 { 71 for (int first = 0, last = bytes.Length - 1; first < last; first++, last--) 72 { 73 byte temp = bytes[first]; 74 bytes[first] = bytes[last]; 75 bytes[last] = temp; 76 } 77 } 78 } 79 }