| 1 | // Copyright (c) .NET Foundation and contributors. All rights reserved. Licensed under the Microsoft Reciprocal License. See LICENSE.TXT file in the project root for full license information. |
| 2 | |
| 3 | namespace WixToolset.Core.WindowsInstaller.Bind |
| 4 | { |
| 5 | using System; |
| 6 | using System.Collections.Generic; |
| 7 | using System.IO; |
| 8 | using WixToolset.Extensibility; |
| 9 | using WixToolset.Extensibility.Services; |
| 10 | |
| 11 | internal class FileSystemManager |
| 12 | { |
| 13 | public FileSystemManager(IFileSystem fileSystem, IEnumerable<IFileSystemExtension> fileSystemExtensions) |
| 14 | { |
| 15 | this.FileSystem = fileSystem; |
| 16 | this.Extensions = fileSystemExtensions; |
| 17 | } |
| 18 | |
| 19 | private IFileSystem FileSystem { get; } |
| 20 | |
| 21 | private IEnumerable<IFileSystemExtension> Extensions { get; } |
| 22 | |
| 23 | public bool CompareFiles(string firstPath, string secondPath) |
| 24 | { |
| 25 | foreach (var extension in this.Extensions) |
| 26 | { |
| 27 | var compared = extension.CompareFiles(firstPath, secondPath); |
| 28 | if (compared.HasValue) |
| 29 | { |
| 30 | return compared.Value; |
| 31 | } |
| 32 | } |
| 33 | |
| 34 | return this.BuiltinCompareFiles(firstPath, secondPath); |
| 35 | } |
| 36 | |
| 37 | private bool BuiltinCompareFiles(string firstPath, string secondPath) |
| 38 | { |
| 39 | if (String.Equals(firstPath, secondPath, StringComparison.OrdinalIgnoreCase)) |
| 40 | { |
| 41 | return true; |
| 42 | } |
| 43 | |
| 44 | using (var firstStream = this.FileSystem.OpenFile(null, firstPath, FileMode.Open, FileAccess.Read, FileShare.Read)) |
| 45 | using (var secondStream = this.FileSystem.OpenFile(null, secondPath, FileMode.Open, FileAccess.Read, FileShare.Read)) |
| 46 | { |
| 47 | if (firstStream.Length != secondStream.Length) |
| 48 | { |
| 49 | return false; |
| 50 | } |
| 51 | |
| 52 | // Using a larger buffer than the default buffer of 4 * 1024 used by FileStream.ReadByte improves performance. |
| 53 | // The buffer size is based on user feedback. Based on performance results, a better buffer size may be determined. |
| 54 | var firstBuffer = new byte[16 * 1024]; |
| 55 | var secondBuffer = new byte[16 * 1024]; |
| 56 | |
| 57 | var firstReadLength = 0; |
| 58 | do |
| 59 | { |
| 60 | firstReadLength = firstStream.Read(firstBuffer, 0, firstBuffer.Length); |
| 61 | var secondReadLength = secondStream.Read(secondBuffer, 0, secondBuffer.Length); |
| 62 | |
| 63 | if (firstReadLength != secondReadLength) |
| 64 | { |
| 65 | return false; |
| 66 | } |
| 67 | |
| 68 | for (var i = 0; i < firstReadLength; ++i) |
| 69 | { |
| 70 | if (firstBuffer[i] != secondBuffer[i]) |
| 71 | { |
| 72 | return false; |
| 73 | } |
| 74 | } |
| 75 | } while (0 < firstReadLength); |
| 76 | } |
| 77 | |
| 78 | return true; |
| 79 | } |
| 80 | } |
| 81 | } |