1 files changed, 127 insertions, 0 deletions

diff --git a/src/samples/Dtf/DDiff/MspDiffEngine.cs b/src/samples/Dtf/DDiff/MspDiffEngine.cs
new file mode 100644
index 00000000..285bc83d
--- /dev/null
+++ b/src/samples/Dtf/DDiff/MspDiffEngine.cs
@@ -0,0 +1,127 @@
+// 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.
+
+using System;
+using System.IO;
+using WixToolset.Dtf.WindowsInstaller;
+using WixToolset.Dtf.WindowsInstaller.Package;
+
+namespace WixToolset.Dtf.Samples.DDiff
+{
+        public class MspDiffEngine : MsiDiffEngine
+        {
+                public MspDiffEngine()
+                {
+                }
+
+                private string GetPatchTargetOption(string[] options)
+                {
+                        for(int i = 0; i < options.Length - 1; i++)
+                        {
+                                switch(options[i].ToLower())
+                                {
+                                        case "/p": goto case "-patchtarget";
+                                        case "-p": goto case "-patchtarget";
+                                        case "/patchtarget": goto case "-patchtarget";
+                                        case "-patchtarget": return options[i+1];
+                                }
+                        }
+                        return null;
+                }
+
+                public override float GetDiffQuality(string diffInput1, string diffInput2, string[] options, IDiffEngineFactory diffFactory)
+                {
+                        if(diffInput1 != null && File.Exists(diffInput1) &&
+                                diffInput2 != null && File.Exists(diffInput2) &&
+                                GetPatchTargetOption(options) != null &&
+                                (IsMspPatch(diffInput1) && IsMspPatch(diffInput2)))
+                        {
+                                return .80f;
+                        }
+                        else if(diffInput1 != null && File.Exists(diffInput1) &&
+                                diffInput2 != null && File.Exists(diffInput2) &&
+                                GetPatchTargetOption(options) == null &&
+                                (IsMspPatch(diffInput1) && IsMsiDatabase(diffInput2)) ||
+                                (IsMsiDatabase(diffInput1) && IsMspPatch(diffInput2)))
+                        {
+                                return .75f;
+                        }
+                        else
+                        {
+                                return 0;
+                        }
+                }
+
+                public override bool GetDiff(string diffInput1, string diffInput2, string[] options, TextWriter diffOutput, string linePrefix, IDiffEngineFactory diffFactory)
+                {
+                        bool difference = false;
+
+                        InstallPackage db1, db2;
+                        if(IsMspPatch(diffInput1))
+                        {
+                                string patchTargetDbFile = GetPatchTargetOption(options);
+                                if(patchTargetDbFile == null) patchTargetDbFile = diffInput2;
+                                string tempPatchedDbFile = Path.GetTempFileName();
+                                File.Copy(patchTargetDbFile, tempPatchedDbFile, true);
+                                File.SetAttributes(tempPatchedDbFile, File.GetAttributes(tempPatchedDbFile) & ~System.IO.FileAttributes.ReadOnly);
+                                db1 = new InstallPackage(tempPatchedDbFile, DatabaseOpenMode.Direct);
+                                db1.ApplyPatch(new PatchPackage(diffInput1), null);
+                                db1.Commit();
+                        }
+                        else
+                        {
+                                db1 = new InstallPackage(diffInput1, DatabaseOpenMode.ReadOnly);
+                        }
+                        if(IsMspPatch(diffInput2))
+                        {
+                                string patchTargetDbFile = GetPatchTargetOption(options);
+                                if(patchTargetDbFile == null) patchTargetDbFile = diffInput1;
+                                string tempPatchedDbFile = Path.GetTempFileName();
+                                File.Copy(patchTargetDbFile, tempPatchedDbFile, true);
+                                File.SetAttributes(tempPatchedDbFile, File.GetAttributes(tempPatchedDbFile) & ~System.IO.FileAttributes.ReadOnly);
+                                db2 = new InstallPackage(tempPatchedDbFile, DatabaseOpenMode.Direct);
+                                db2.ApplyPatch(new PatchPackage(diffInput2), null);
+                                db2.Commit();
+                        }
+                        else
+                        {
+                                db2 = new InstallPackage(diffInput2, DatabaseOpenMode.ReadOnly);
+                        }
+
+                        if(GetSummaryInfoDiff(db1, db2, options, diffOutput, linePrefix, diffFactory)) difference = true;
+                        if(GetDatabaseDiff(db1, db2, options, diffOutput, linePrefix, diffFactory)) difference = true;
+                        if(GetStreamsDiff(db1, db2, options, diffOutput, linePrefix, diffFactory)) difference = true;
+
+                        db1.Close();
+                        db2.Close();
+
+                        try
+                        {
+                                if(IsMspPatch(diffInput1)) File.Delete(db1.FilePath);
+                                if(IsMspPatch(diffInput1)) File.Delete(db2.FilePath);
+                        }
+                        catch(IOException)
+                        {
+                                #if DEBUG
+                                Console.WriteLine("Could not delete temporary files {0} and {1}", db1.FilePath, db2.FilePath);
+                                #endif
+                        }
+
+                        if(IsMspPatch(diffInput1) && IsMspPatch(diffInput2))
+                        {
+                                Database dbp1 = new Database(diffInput1, DatabaseOpenMode.ReadOnly);
+                                Database dbp2 = new Database(diffInput2, DatabaseOpenMode.ReadOnly);
+
+                                if(GetStreamsDiff(dbp1, dbp2, options, diffOutput, linePrefix, diffFactory)) difference = true;
+                                dbp1.Close();
+                                dbp2.Close();
+                        }
+
+                        return difference;
+                }
+
+                public override IDiffEngine Clone()
+                {
+                        return new MspDiffEngine();
+                }
+        }
+}