MspDiffEngine.cs :  » Installers-Generators » WiX » Microsoft » Deployment » Samples » DDiff » C# / CSharp Open Source

using System;
using System.IO;
using Microsoft.Deployment.WindowsInstaller;
using Microsoft.Deployment.WindowsInstaller.Package;

namespace Microsoft.Deployment.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();
    }
  }
}