LogFileCopy.targets

<Project xmlns="http://schemas.microsoft.com/developer/msbuild/2003">

    <UsingTask TaskName="Copy" TaskFactory="CodeTaskFactory" AssemblyFile="$(MSBuildToolsPath)\Microsoft.Build.Tasks.Core.dll">
    <ParameterGroup>
      <SourceFiles Required="true" ParameterType="Microsoft.Build.Framework.ITaskItem[]" />
      <DestinationFolder ParameterType="Microsoft.Build.Framework.ITaskItem" />
      <Retries ParameterType="System.Int32" />
      <RetryDelayMilliseconds ParameterType="System.Int32" />
      <UseHardlinksIfPossible ParameterType="System.Boolean" />
      <SkipUnchangedFiles ParameterType="System.Boolean" />
      <DestinationFiles Output="true" ParameterType="Microsoft.Build.Framework.ITaskItem[]" />
      <CopiedFiles Output="true" ParameterType="Microsoft.Build.Framework.ITaskItem[]" />
      <OverwriteReadOnlyFiles ParameterType="System.Boolean" />
    </ParameterGroup>
    <Task>
      <Reference Include="mscorlib" />
      <Reference Include="Microsoft.Build" />
      <Reference Include="Microsoft.Build.Framework" />
      <Reference Include="Microsoft.Build.Tasks.Core" />
      <Using Namespace="System" />
      <Using Namespace="System.Linq" />
      <Using Namespace="System.Text" />
      <Using Namespace="Microsoft.Build.Framework" />
      <Using Namespace="Microsoft.Build.Shared" />
      <Using Namespace="Microsoft.Build.Tasks" />
      <Using Namespace="Microsoft.Build.Utilities" />
      <Code Type="Fragment" Language="cs">
        <![CDATA[

Func<Microsoft.Build.Tasks.Copy, string> PrintItems = c => 
{
    var sb = new StringBuilder();

    for (int i = 0; i < c.SourceFiles.Length; i++)
    {
        var sourcePath = c.SourceFiles[i].GetMetadata("FullPath");
        var destinationPath = c.DestinationFiles[i].GetMetadata("FullPath");
        if (sourcePath != destinationPath)
        {
            sb.AppendLine(sourcePath);
            sb.AppendLine(destinationPath);
        }
    }

    return sb.ToString();
};

var copy = new Microsoft.Build.Tasks.Copy();
copy.BuildEngine = BuildEngine;
copy.SourceFiles = SourceFiles;
copy.DestinationFolder = DestinationFolder;
copy.DestinationFiles = DestinationFiles;
copy.Retries = Retries;
copy.RetryDelayMilliseconds = RetryDelayMilliseconds;
copy.UseHardlinksIfPossible = UseHardlinksIfPossible;
copy.SkipUnchangedFiles = SkipUnchangedFiles;
copy.OverwriteReadOnlyFiles = OverwriteReadOnlyFiles;
var result = copy.Execute();

lock(this.GetType())
{
    File.AppendAllText("copylog.txt", PrintItems(copy));
}

return result;
]]>
      </Code>
    </Task>
  </UsingTask>

</Project>