Customizing NSIS installer using CPACK

Question

I am trying to customize an NSIS installer using CMAKE and CPACK. In particular I would like to include in the generated project.nsi an external script.

Something like:

!include "@SCRIPT_PATH@\@[email protected]"

To do so I am following the example shown here: https://gitlab.kitware.com/cmake/community/-/wikis/doc/cpack/NSISAdvancedTips

I have copied the template script file (NSIS.template.in) and added the required commands. I now need to configure the two variables "@SCRIPT_PATH@ and @SCRIPT_NAME@ accordingly.

I tried to set them like standard CMAKE variables

SET(SCRIPT_PATH "somePath")
SET(SCRIPT_NAME "someName")

but the template variables are simply left blank by CPACK

Any clue?

Answer 1

I have found a working solution.

Start by adding a placeholder in the main NSIS.template.in where you want to insert new commands, for instance:

@NSIS_ADDITIONAL_SCRIPT@

Then you need to configure a template file containing options that will be passed to the CPACK build.

The CPackOptions.cmake contains the following:

SET(NSIS_ADDITIONAL_SCRIPT ${NSIS_ADDITIONAL_SCRIPT})

Then in your CMAKE script before including CPACK you need to set the NSIS_ADDITIONAL_SCRIPT variable (the path is reworked in order to have the correct set of backslashes on window systems)

SET(scriptPath "[path to the script location]" )
FILE(TO_NATIVE_PATH ${scriptPath} scriptPath )
STRING(REPLACE "\\" "\\\\" scriptPath  ${scriptPath} ) 

and finally configure the CPackOption.cmake file (watch out for the correct number of slashes and comas)

SET(NSIS_ADDITIONAL_SCRIPT " \"!include \\\"${scriptPath}\\\" \\n  \" ")
CONFIGURE_FILE( ${CMAKE_SOURCE_DIR}/CMakeConf/CPackOptions.cmake ${PROJECT_BINARY_DIR}/CPackOptions.cmake)

If you do everything correctly:

• by configuring and generating the CMAKE script you will find the file CPackOptions.cmake in your project build folder.
• This configured file will be then used by CPACK to fill in the variable added in the NSIStemplate.in.
• The final generated project.nsi will contain the additional !include instruction

Answer 2

I know this is old but it may help some folks out there:

The solution to your problem is to prefix your variables, SCRIPT_PATH and SCRIPT_NAME by CPACK. So that it will be CPACK_SCRIPT_PATH...

That way when CMake process your CmakeLists it knows that your variables should be set for CPack (in other word when generating CPackConfig.cmake).