Compile-time wildcards in cmake install targets

Question

I'm new to cmake and I'm finding it very frustrating. I am trying to use wildcards in file paths that are evaluated when the build runs, not when the build is generated.

I have created a build that uses SWIG to generate Java wrappers for some C++ code. I can write the commands to generate the native code, compile it, and produce a working shared library, and even use the INSTALL command to install that shared library correctly. What I can't figure out how to do is to write an INSTALL command that can copy all *.java files generated by SWIG into that same install location.

It seems that cmake's FILE GLOB command does the globbing when cmake is executed, and not when the build actually runs. Of course, when cmake is executed, SWIG hasn't run yet, and the Java files don't exist.

Is there a way to do what I want? Am I going about things wrong? It seems like this is such a fundamental part of what Makefiles need to do, I'm really surprised not to find an easy way to do it.

Answer 1

Assuming that the Java wrappers are located in the current binary directory, you can use the following install command to copy the Java files upon install:

install(
    CODE "file( GLOB _GeneratedJavaSources \"${CMAKE_CURRENT_BINARY_DIR}/*.java\" )"
    CODE "file( INSTALL \${_GeneratedJavaSources} DESTINATION \"$ENV{HOME}\" )"
)

The CODE form of the install command is used to execute two CMake commands upon running the install target. The first one collects all generated Java files in a helper variable. The second one uses the INSTALL form of the file command to copy the files.

Answer 2

you can use install(SCRIPT swigInstaller.cmake) or install(DIRECTORY) both of which supports doing file globing at install time. You can read more about the install command at:

http://cmake.org/cmake/help/cmake-2-8-docs.html#command:install