Default STM32_CUBE_family_PATH is not being set

[BenArtes]

Describe the bug
After a clean clone of this repository, I installed the STM32CubeF4 drivers to /opt/STM32CubeF4 and tried to build the blinky example. Instead of using the default path I was met with an error indicating that a blank path was being used and that CMSIS could NOT be found:

-- No STM32_TOOLCHAIN_PATH specified, using default: /usr
-- No STM32_TARGET_TRIPLET specified, using default: arm-none-eabi
-- The C compiler identification is GNU 6.3.1
-- The ASM compiler identification is GNU
-- Found assembler: /usr/bin/arm-none-eabi-gcc
-- Check for working C compiler: /usr/bin/arm-none-eabi-gcc
-- Check for working C compiler: /usr/bin/arm-none-eabi-gcc -- works
-- Detecting C compiler ABI info
-- Detecting C compiler ABI info - done
-- Detecting C compile features
-- Detecting C compile features - done
-- Neither STM32_CUBE_F4_PATH nor STM32_CMSIS_F4_PATH specified using default  STM32_CUBE_F4_PATH: 
CMake Error at /usr/local/lib/python3.6/dist-packages/cmake/data/share/cmake-3.13/Modules/FindPackageHandleStandardArgs.cmake:137 (message):
  Could NOT find CMSIS (missing: CMSIS_INCLUDE_DIRS CMSIS_SOURCES STM32F4)
  (found version "v1.0.4")
Call Stack (most recent call first):
  /usr/local/lib/python3.6/dist-packages/cmake/data/share/cmake-3.13/Modules/FindPackageHandleStandardArgs.cmake:378 (_FPHSA_FAILURE_MESSAGE)
  /home/terminus/stm32-cmake/cmake/FindCMSIS.cmake:183 (find_package_handle_standard_args)
  CMakeLists.txt:30 (find_package)

In FindCMSIS.cmake lines 74-81 there are two attempts to set STM32_CUBE_${family}_PATH, first from an ENV variable, then from the default value. Both use cmake's set(... CACHE PATH) and I'm wondering if the first attempt to set from the ENV variable is preventing the default from succeeding.

Two different modifications to this file worked, but I'm not sure which is preferred:

1) Checking ENV variable before attempting to set STM32_CUBE_${FAMILY}_PATH

    if((NOT STM32_CMSIS_${FAMILY}_PATH) AND (NOT STM32_CUBE_${FAMILY}_PATH) AND ($ENV{STM32_CUBE_${FAMILY}_PATH}))
        set(STM32_CUBE_${FAMILY}_PATH $ENV{STM32_CUBE_${FAMILY}_PATH} CACHE PATH "Path to STM32Cube${FAMILY}")
    endif()

    if((NOT STM32_CMSIS_${FAMILY}_PATH) AND (NOT STM32_CUBE_${FAMILY}_PATH))
        set(STM32_CUBE_${FAMILY}_PATH /opt/STM32Cube${FAMILY} CACHE PATH "Path to STM32Cube${FAMILY}")
        message(STATUS "Neither STM32_CUBE_${FAMILY}_PATH nor STM32_CMSIS_${FAMILY}_PATH specified using default  STM32_CUBE_${FAMILY}_PATH: ${STM32_CUBE_${FAMILY}_PATH}")
    endif()

2) Forcing Default Setting using set's FORCE optional

    if((NOT STM32_CMSIS_${FAMILY}_PATH) AND (NOT STM32_CUBE_${FAMILY}_PATH))
        set(STM32_CUBE_${FAMILY}_PATH $ENV{STM32_CUBE_${FAMILY}_PATH} CACHE PATH "Path to STM32Cube${FAMILY}")
    endif()

    if((NOT STM32_CMSIS_${FAMILY}_PATH) AND (NOT STM32_CUBE_${FAMILY}_PATH))
        set(STM32_CUBE_${FAMILY}_PATH /opt/STM32Cube${FAMILY} CACHE PATH "Path to STM32Cube${FAMILY}" FORCE)
        message(STATUS "Neither STM32_CUBE_${FAMILY}_PATH nor STM32_CMSIS_${FAMILY}_PATH specified using default  STM32_CUBE_${FAMILY}_PATH: ${STM32_CUBE_${FAMILY}_PATH}")
    endif()

A similar code is located in FindHAL.cmake Line74-81 and FinaBSP.cmake Lines 265-272, though these don't seem to cause the same issue.

I'm happy to create a pull request with these changes once I know which files to change and the preferred solution.

Environment (please complete the following information):

• OS: Ubuntu 18.04
• Compiler: arm-none-eabi-gcc (15:6.3.1+svn253039-1build1) 6.3.1 20170620
• stm32-cmake: cebbda6

[atsju]

Thank you for reporting this issue. It may be linked to a recent merge of #226. I had no issue running on windows.
Could you please print (message) the value of STM32_CUBE_${FAMILY}_PATH at 3 points (before first if, after first if and at the end) ? I expect path to be something in format -NOT-FOUND.

just for notification: @rmspacefish

[BenArtes]

Message Changes to cmake:

    message("Before First If: " ${STM32_CUBE_${FAMILY}_PATH})
    if((NOT STM32_CMSIS_${FAMILY}_PATH) AND (NOT STM32_CUBE_${FAMILY}_PATH))
        set(STM32_CUBE_${FAMILY}_PATH $ENV{STM32_CUBE_${FAMILY}_PATH} CACHE PATH "Path to STM32Cube${FAMILY}")
    endif()

    message("After First If: " ${STM32_CUBE_${FAMILY}_PATH})
    if((NOT STM32_CMSIS_${FAMILY}_PATH) AND (NOT STM32_CUBE_${FAMILY}_PATH))
        set(STM32_CUBE_${FAMILY}_PATH /opt/STM32Cube${FAMILY} CACHE PATH "Path to STM32Cube${FAMILY}" )
        message(STATUS "Neither STM32_CUBE_${FAMILY}_PATH nor STM32_CMSIS_${FAMILY}_PATH specified using default  STM32_CUBE_${FAMILY}_PATH: ${STM32_CUBE_${FAMILY}_PATH}")
    endif()
    message("End: " ${STM32_CUBE_${FAMILY}_PATH})

Messages Without Fixes:

Before First If: 
After First If: 
-- Neither STM32_CUBE_F4_PATH nor STM32_CMSIS_F4_PATH specified using default  STM32_CUBE_F4_PATH: 
End: 

Messages With Fixes:

Before First If: 
After First If: 
-- Neither STM32_CUBE_F4_PATH nor STM32_CMSIS_F4_PATH specified using default  STM32_CUBE_F4_PATH: /opt/STM32CubeF4
End: /opt/STM32CubeF4

[atsju]

Thank you very much.
Please do the PR with FORCE solution. Also have a look at #226 and add the FORCE to all relevant places.

[robamu]

I did not account for the ENV variable being empty. I might look into checking the existence of ENV variables for other cases like the FREERTOS_PATH as well.

It might also be a good idea to check whether /opt/STM32Cube${FAMILY} exists as a directory as mentioned in #232 .
If all check fails because the variable was not defined as a regular CMake variable, passed via command line, set in ENV or Cube installed in default location, I would say its best to stop with message(FATAL_ERROR ...).

[atsju]

@BenArtes
I think @rmspacefish is right and it was your proposal number 1 but I did read too fast.
Could you please use the defined env format if it's not too much asking for this modification.

Side note about the PR: I think you misconfigured your email address localy. Github doesn't see "you" as author of commit.

[BenArtes]

Updated the PR, to use defined envs, and check path for existence.

Also updated local email address.