cmake: new add_option_defs helper, add KEYLOG_EXPORT build param

[redbaron]

Description

Add add_option_defs helper which cover simple case of setting compile definitions when build option is selected. New helper uses named arguments and adds following QoL improvements:

• optionally infer default values from list of possible values. First possible value becomes default.
• optionally append default value to helper string. Helper string and default values can't go out of sync
• support adding defines if build option is set. It covers many simple cases like new WOLFSSL_KEYLOG_EXPORT

Fixes #8165

Testing

1. Build before and after patch, diffed CMakeCache.txt files to find only new WOLFSSL_KEYLOG_EXPORT function is different.

Checklist

• added tests
• updated/added doxygen
• updated appropriate READMEs
• Updated manual and documentation

[wolfSSL-Bot]

Can one of the admins verify this patch?

[redbaron]

I don't understand purpose this if() in original function. I transformed it mechanically to new args so it should work as before.

when building there is no difference in CMakeCache.txt before and after, so this branch either never triggered or mechanical transformation works as before.

[redbaron]

OK, I think I get it. It triggers when build options is passed via command line with value which is not among the list of supported values, like we pass "ON" for values like "yes|no" This works with booleans, but doesn't it break build options where string input is expected?

[bigbrett]

@redbaron sorry accidentally deleted my previous response.

You are correct, this looks like it squashes non-boolean values inappropriately. Could you add a check for this case, to ensure this doesn't happen? Something like this to fall back to defaults maybe?

if(DEFINED ${NAME})
    list(FIND VALUES ${${NAME}} IDX)

    # Apply override only if VALUES is yes/no
    if (VALUES STREQUAL "yes;no" OR VALUES STREQUAL "no;yes")
        if (${IDX} EQUAL -1)
            # Interpret CMake truthiness for boolean-like values
            if(${${NAME}})
                override_cache(${NAME} "yes")
            else()
                override_cache(${NAME} "no")
            endif()
        endif()
    else()
        # For non-boolean VALUES, reset to default or error on invalid input
        if (${IDX} EQUAL -1)
            message(WARNING "Invalid value for ${NAME}. Resetting to default: ${DEFAULT}")
            set(${NAME} ${DEFAULT} CACHE STRING "${HELP_STRING}")
        endif()
    endif()
endif()

[embhorn]

Hi @redbaron

Thanks for opening this PR. We require contributors to be approved by the wolfSSL team. Could you please send an email to [email protected] to request an application form?

Thanks,
@embhorn - wolfSSL Support

[embhorn]

@redbaron is approved as a wolfSSL contributor

[bigbrett]

@redbaron sorry accidentally deleted my previous response.

You are correct, this looks like it squashes non-boolean values inappropriately. Could you add a check for this case, to ensure this doesn't happen? Something like this to fall back to defaults maybe?

if(DEFINED ${NAME})
    list(FIND VALUES ${${NAME}} IDX)

    # Apply override only if VALUES is yes/no
    if (VALUES STREQUAL "yes;no" OR VALUES STREQUAL "no;yes")
        if (${IDX} EQUAL -1)
            # Interpret CMake truthiness for boolean-like values
            if(${${NAME}})
                override_cache(${NAME} "yes")
            else()
                override_cache(${NAME} "no")
            endif()
        endif()
    else()
        # For non-boolean VALUES, reset to default or error on invalid input
        if (${IDX} EQUAL -1)
            message(WARNING "Invalid value for ${NAME}. Resetting to default: ${DEFAULT}")
            set(${NAME} ${DEFAULT} CACHE STRING "${HELP_STRING}")
        endif()
    endif()
endif()