1 files changed, 146 insertions, 0 deletions

diff --git a/src/WixToolset.BuildTasks/GenerateCompileWithObjectPath.cs b/src/WixToolset.BuildTasks/GenerateCompileWithObjectPath.cs
new file mode 100644
index 00000000..06c8b98a
--- /dev/null
+++ b/src/WixToolset.BuildTasks/GenerateCompileWithObjectPath.cs
@@ -0,0 +1,146 @@
+// 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.
+
+namespace WixToolset.BuildTasks
+{
+    using System;
+    using System.Collections.Generic;
+    using System.Diagnostics.CodeAnalysis;
+    using System.Globalization;
+    using System.IO;
+    using System.Security.Cryptography;
+    using System.Text;
+    using Microsoft.Build.Framework;
+    using Microsoft.Build.Utilities;
+
+    /// <summary>
+    /// This task generates metadata on the for compile output objects.
+    /// </summary>
+    public class GenerateCompileWithObjectPath : Task
+    {
+        /// <summary>
+        /// The list of files to generate outputs for.
+        /// </summary>
+        [Required]
+        public ITaskItem[] Compile
+        {
+            get;
+            set;
+        }
+
+        /// <summary>
+        /// The list of files with ObjectPath metadata.
+        /// </summary>
+        [Output]
+        public ITaskItem[] CompileWithObjectPath
+        {
+            get;
+            private set;
+        }
+
+        /// <summary>
+        /// The folder under which all ObjectPaths should reside.
+        /// </summary>
+        [Required]
+        public string IntermediateOutputPath
+        {
+            get;
+            set;
+        }
+
+        /// <summary>
+        /// Generate an identifier by hashing data from the row.
+        /// </summary>
+        /// <param name="prefix">Three letter or less prefix for generated row identifier.</param>
+        /// <param name="args">Information to hash.</param>
+        /// <returns>The generated identifier.</returns>
+        [SuppressMessage("Microsoft.Globalization", "CA1303:DoNotPassLiteralsAsLocalizedParameters", MessageId = "System.InvalidOperationException.#ctor(System.String)")]
+        public static string GenerateIdentifier(string prefix, params string[] args)
+        {
+            string stringData = String.Join("|", args);
+            byte[] data = Encoding.Unicode.GetBytes(stringData);
+
+            // hash the data
+            byte[] hash;
+
+            using (MD5 md5 = new MD5CryptoServiceProvider())
+            {
+                hash = md5.ComputeHash(data);
+            }
+
+            // build up the identifier
+            StringBuilder identifier = new StringBuilder(35, 35);
+            identifier.Append(prefix);
+
+            // hard coded to 16 as that is the most bytes that can be used to meet the length requirements. SHA1 is 20 bytes.
+            for (int i = 0; i < 16; i++)
+            {
+                identifier.Append(hash[i].ToString("X2", CultureInfo.InvariantCulture.NumberFormat));
+            }
+
+            return identifier.ToString();
+        }
+
+        /// <summary>
+        /// Gets the full path of the directory in which the file is found.
+        /// </summary>
+        /// <param name='file'>The file from which to extract the directory.</param>
+        /// <returns>The generated identifier.</returns>
+        private static string GetDirectory(ITaskItem file)
+        {
+            return file.GetMetadata("RootDir") + file.GetMetadata("Directory");
+        }
+
+        /// <summary>
+        /// Sets the object path to use for the file.
+        /// </summary>
+        /// <param name='file'>The file on which to set the ObjectPath metadata.</param>
+        /// <remarks>
+        /// For the same input path it will return the same ObjectPath. Case is not ignored, however that isn't a problem.
+        /// </remarks>
+        private void SetObjectPath(ITaskItem file)
+        {
+            // If the source file is in the project directory or in the intermediate directory, use the intermediate directory.
+            if (string.IsNullOrEmpty(file.GetMetadata("RelativeDir")) || string.Compare(file.GetMetadata("RelativeDir"), this.IntermediateOutputPath, StringComparison.OrdinalIgnoreCase) == 0)
+            {
+                file.SetMetadata("ObjectPath", this.IntermediateOutputPath);
+            }
+            // Otherwise use a subdirectory of the intermediate directory. The subfolder's name is based on the full path of the folder containing the source file.
+            else
+            {
+                file.SetMetadata("ObjectPath", Path.Combine(this.IntermediateOutputPath, GenerateIdentifier("pth", GetDirectory(file))) + Path.DirectorySeparatorChar);
+            }
+        }
+
+        /// <summary>
+        /// Gets a complete list of external cabs referenced by the given installer database file.
+        /// </summary>
+        /// <returns>True upon completion of the task execution.</returns>
+        public override bool Execute()
+        {
+            if (string.IsNullOrEmpty(this.IntermediateOutputPath))
+            {
+                this.Log.LogError("IntermediateOutputPath parameter is required and cannot be empty");
+                return false;
+            }
+
+            if (this.Compile == null || this.Compile.Length == 0)
+            {
+                return true;
+            }
+
+            this.CompileWithObjectPath = new ITaskItem[this.Compile.Length];
+            for (int i = 0; i < this.Compile.Length; ++i)
+            {
+                this.CompileWithObjectPath[i] = new TaskItem(this.Compile[i].ItemSpec, this.Compile[i].CloneCustomMetadata());
+
+                // Do not overwrite the ObjectPath metadata if it already was set.
+                if (string.IsNullOrEmpty(this.CompileWithObjectPath[i].GetMetadata("ObjectPath")))
+                {
+                    SetObjectPath(this.CompileWithObjectPath[i]);
+                }
+            }
+
+            return true;
+        }
+    }
+}