CMake graphviz auto generated

Question

I know the common way to generate a CMake project dependencies graph by the CLI:

cmake --graphviz=[file]

But is there a way for it to be autogenerated by just setting a flag or command within a CMakeList? The idea is for the CMakeLists.txt itself to trigger the graph generation, and not the user through command line.

Answer 1

You could call CMake inside your script again, e.g. like:

add_custom_target(graphviz ALL
                  "${CMAKE_COMMAND}" "--graphviz=foo" .
                  WORKING_DIRECTORY "${CMAKE_BINARY_DIR}")

Answer 2

Not only can you create a CMake custom target for running Graphviz, but you can take it a step further, and have it also generate the image files for you using Dot:

add_custom_target(graphviz ALL
    COMMAND ${CMAKE_COMMAND} "--graphviz=foo.dot" .
    COMMAND dot -Tpng foo.dot -o foo.png
    WORKING_DIRECTORY "${CMAKE_BINARY_DIR}"
)

This way, the custom target runs the second command dot -Tpng foo.dot -o foo.png as well. You can output the image files anywhere on your system by pre-pending foo.png with a path of your choosing.