Determine whether it's a build or rebuild in .cmd script called in prelink step inside Visual Studio

Question

How can a .cmd script run from within a Visual Studio (2005, 2008, 2010, 2012 and 2013 respectively) project's pre-link stage determine whether this is a full rebuild (Build.RebuildSolution/Build.RebuildOnlyProject) or "ordinary" build (Build.BuildSolution/Build.BuildOnlyProject)?

This is an external script (LuaJIT, if you must know) and I don't want to rebuild the library every single build of the project. Instead I'd like to limit the complete rebuild to situations where I choose exactly that option.

Answer 1

How can a .cmd script run from within a Visual Studio (2005, 2008, 2010, 2012 and 2013 respectively) project's pre-link stage determine whether this is a full rebuild ... or "ordinary" build ... ?

I do not know if the exact thing that you are asking can be done - perhaps someone else knows how to do it. I will, however, suggest an alternate approach.

My approach is to remove the build of the Lua library from the pre-link step to a separate Visual Studio NMake project. If you create an NMake project, you will be able to know which type of build (build or rebuild) is occurring.

Note that later versions of Visual Studio simply refer to the project type as "Make". For discussion purposes here, I will refer to the project type as "NMake". I believe this is just a naming difference, and that the underlying build project remains the same between the two versions.

As a simple test, I created two Visual Studio applications: 1) an NMake project that calls a batch file to create a static library, and 2) a console application that consumes the library from step 1.

The NMake Project

In Visual Studio, if you create a new NMake project, you will see a dialog that allows you to provide MS-DOS commands:

As you can see, there are commands for: Build, Clean, Rebuild, and others. I don't have a screen shot of the above dialog with my commands, but here is my NMake project's properties:

My Build command just checks for the existence of the output file (lua.lib). If it does not exist, then it calls the rebuild.bat batch file. My Rebuild command always calls the batch file. My Clean command just deletes the output. I am not really sure what the Output command is used for, but I just filled in the path to the build output (lua.lib).

Now if you do a build, the lua.lib file will only be created if it is not there. If it is already there, nothing is done. If you do a rebuild, then a new lua.lib file is created.

The Console Application

In my console application, I added a reference to the NMake project - this way the NMake project is built prior to the console application. Here is the console application's reference page:

I also added the lua.lib file as an input during the application's link stage:

When the console application is built (during a build), it will build the NMake project if needed, and use the output (lua.lib) during the linker stage. When the console application is rebuilt (during a rebuild), it will also rebuild the NMake project.

Other Thoughts

My screen shots above only show the debug version of the properties. Your projects will have to account for the release version. There probably is a VS macro to handle this, but I am not sure since it has been ages since I've done anything with C/ C++.

In my testing above I use a single build batch file for both the build and rebuild. Obviously, you could do the same or you could use different batch files.

Answer 2

Ok, this is going to be a long one.

First of all - do not take my code 'as is' - it is terrible one with lots of hacks, I had no idea msbuild is so broken by default (it seems at work I have access to waaaay more commands that make life easier). And another thing - it seems vcxproj is broken at some poin - I was not able to integrate the way I wanted with only BeforeRebuild and AfterRebuild targets - I had to redefine hole Rebuild target (it is located in C:\Windows\Microsoft.NET\Framework\v4.0.30319\Microsoft.Common.targets)

So, the idea is the following: when a Rebuild is happening we create an anchor. Then, during PreLink stage we execute cmd which is able to use created anchor. If the anchor is in place - we deal with Rebuild, if there is no anchor - it is a simple Build. After Rebuild is done - we delete the anchor.

modifications in vcxproj file:

<?xml version="1.0" encoding="utf-8"?>
<Project DefaultTargets="Build" ToolsVersion="4.0" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
  ....
  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'" Label="Configuration">
    ....
    <PreLinkEventUseInBuild>true</PreLinkEventUseInBuild>
    ....
  </PropertyGroup>
  ....
  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">
    .....
    <PreLinkEvent>
      <Command>D:\PreLink\b.cmd</Command>
    </PreLinkEvent>
    .....
  </ItemDefinitionGroup>
  .....
  <Target Name="BeforeRebuild">
    <Exec Command="echo 2 &gt; D:\PreLink\2.txt" />
  </Target>
  <Target Name="AfterRebuild">
    <Exec Command="del D:\PreLink\2.txt" />
  </Target>
  <!-- This was copied from MS file -->
  <PropertyGroup>

    <_ProjectDefaultTargets Condition="'$(MSBuildProjectDefaultTargets)' != ''">$(MSBuildProjectDefaultTargets)</_ProjectDefaultTargets>
    <_ProjectDefaultTargets Condition="'$(MSBuildProjectDefaultTargets)' == ''">Build</_ProjectDefaultTargets>

    <RebuildDependsOn>
      BeforeRebuild;
      Clean;
      $(_ProjectDefaultTargets);
      AfterRebuild;
    </RebuildDependsOn>

    <RebuildDependsOn Condition=" '$(MSBuildProjectDefaultTargets)' == 'Rebuild' " >
      BeforeRebuild;
      Clean;
      Build;
      AfterRebuild;
    </RebuildDependsOn>
  </PropertyGroup>


  <Target
      Name="Rebuild"
      Condition=" '$(_InvalidConfigurationWarning)' != 'true' "
      DependsOnTargets="$(RebuildDependsOn)"
      Returns="$(TargetPath)"/>
  <!-- End of copy -->
</Project>

And the cmd looks like this:

if exist 2.txt (
    echo Rebuild818181
) else (
    echo Build12312312 
)

The output from Output window:

1>Task "Exec" (TaskId:41)
1>  Task Parameter:Command=D:\PreLink\b.cmd
1>  :VCEnd (TaskId:41)
1>  Build12312312 (TaskId:41)

Things to improve:

1. Use normal variables instead of external file (it seems MsBuild extension pack should do it)

2. Probably find a way to override only BeforeRebuild and AfterRebuild instead of the hole Rebuild part

Answer 3

It may be a bit of a hack, but in .csproj file there are sections

<Target Name="BeforeBuild">
</Target>
<Target Name="AfterBuild">
</Target>

You can set an variable from BeforeBuild and retrieve it from cmd script. Later on reset this variable in AfterBuild and you should be good to go.

Answer 4

It is much easier. Just add the following target to your build file or visual Studio Project

  <Target Name="AfterRebuild">
    <Message Text="AFTER REBUILD" Importance="High" />
    <!-- 
        Do whatever Needs to be done on Rebuild - as the message shows in VS Output 
        window it is only executed when an explicit rebuild is triggered  
    -->
  </Target>

If you want a two step solution use this as a template:

  <PropertyGroup>
    <IsRebuild>false</IsRebuild>
  </PropertyGroup>
  <Target Name="BeforeRebuild">
    <Message Text="BEFORE REBUILD" Importance="High" />
      <PropertyGroup>
        <IsRebuild>true</IsRebuild>
      </PropertyGroup>
  </Target>
  <Target Name="BeforeBuild">
    <Message Text="BEFORE BUILD: IsRebuild: $(IsRebuild)" Importance="High" />
  </Target>