Re: [PATCH v2 5/5] cmake: set up proper dependencies for generated clar headers

[Phillip Wood <phillip.wood123@gmail.com>]

Hi Johannes

On 05/11/2024 19:55, Johannes Schindelin wrote:
> Hi Patrick,
> 
> On Mon, 21 Oct 2024, Patrick Steinhardt wrote:
> 
>> The auto-generated headers used by clar are written at configure time
>> and thus do not get regenerated automatically. Refactor the build
>> recipes such that we use custom commands instead, which also has the
>> benefit that we can reuse the same infrastructure as our Makefile.
> 
> For the record: I did not use a shell script to generate the header for a
> specific reason: Unix shell scripts are not native to Windows. Therefore
> they cannot in general be run on Windows, however that was precisely the
> idea for the CMake definition: to be run on a vanilla Windows with Visual
> Studio installed.
> 
> Sadly, even Git's CI definition sets things up in a way that Git for
> Windows' Bash can be used in the CMake definition, but in the intended use
> case (opening a checkout of git/git in Visual Studio without any further
> tools required) won't have a usable Bash.
> 
> Therefore I am unsure whether this patch is desirable.

CMakeLists.txt tries to find sh.exe from git-for-windows and errors out 
if it cannot be found. It then uses that shell to run a number of 
scripts. Perhaps we should do the same in this patch? It would certainly 
be a worthwhile improvement to regenerate this file at build time if the 
source has changed.

Best Wishes

Phillip

> Ciao,
> Johannes
> 
>>
>> Signed-off-by: Patrick Steinhardt <ps@pks.im>
>> ---
>>   contrib/buildsystems/CMakeLists.txt | 50 +++++++----------------------
>>   1 file changed, 12 insertions(+), 38 deletions(-)
>>
>> diff --git a/contrib/buildsystems/CMakeLists.txt b/contrib/buildsystems/CMakeLists.txt
>> index 093852ad9d6..9f80ab92656 100644
>> --- a/contrib/buildsystems/CMakeLists.txt
>> +++ b/contrib/buildsystems/CMakeLists.txt
>> @@ -1002,46 +1002,20 @@ foreach(unit_test ${unit_test_PROGRAMS})
>>   endforeach()
>>
>>   parse_makefile_for_scripts(clar_test_SUITES "CLAR_TEST_SUITES" "")
>> -
>> -set(clar_decls "")
>> -set(clar_cbs "")
>> -set(clar_cbs_count 0)
>> -set(clar_suites "static struct clar_suite _clar_suites[] = {\n")
>> -list(LENGTH clar_test_SUITES clar_suites_count)
>> -foreach(suite ${clar_test_SUITES})
>> -	file(STRINGS "${CMAKE_SOURCE_DIR}/t/unit-tests/${suite}.c" decls
>> -		REGEX "^void test_${suite}__[a-zA-Z_0-9][a-zA-Z_0-9]*\\(void\\)$")
>> -
>> -	list(LENGTH decls decls_count)
>> -	string(REGEX REPLACE "void (test_${suite}__([a-zA-Z_0-9]*))\\(void\\)" "    { \"\\2\", &\\1 },\n" cbs ${decls})
>> -	string(JOIN "" cbs ${cbs})
>> -	list(TRANSFORM decls PREPEND "extern ")
>> -	string(JOIN ";\n" decls ${decls})
>> -
>> -	string(APPEND clar_decls "${decls};\n")
>> -	string(APPEND clar_cbs
>> -		"static const struct clar_func _clar_cb_${suite}[] = {\n"
>> -		${cbs}
>> -		"};\n")
>> -	string(APPEND clar_suites
>> -		"    {\n"
>> -		"        \"${suite}\",\n"
>> -		"        { NULL, NULL },\n"
>> -		"        { NULL, NULL },\n"
>> -		"        _clar_cb_${suite}, ${decls_count}, 1\n"
>> -		"    },\n")
>> -	math(EXPR clar_cbs_count "${clar_cbs_count}+${decls_count}")
>> -endforeach()
>> -string(APPEND clar_suites
>> -	"};\n"
>> -	"static const size_t _clar_suite_count = ${clar_suites_count};\n"
>> -	"static const size_t _clar_callback_count = ${clar_cbs_count};\n")
>> -file(WRITE "${CMAKE_BINARY_DIR}/t/unit-tests/clar-decls.h" "${clar_decls}")
>> -file(WRITE "${CMAKE_BINARY_DIR}/t/unit-tests/clar.suite" "${clar_decls}" "${clar_cbs}" "${clar_suites}")
>> -
>>   list(TRANSFORM clar_test_SUITES PREPEND "${CMAKE_SOURCE_DIR}/t/unit-tests/")
>>   list(TRANSFORM clar_test_SUITES APPEND ".c")
>> -add_library(unit-tests-lib ${clar_test_SUITES} "${CMAKE_SOURCE_DIR}/t/unit-tests/clar/clar.c")
>> +add_custom_command(OUTPUT "${CMAKE_BINARY_DIR}/t/unit-tests/clar-decls.h"
>> +	COMMAND ${CMAKE_SOURCE_DIR}/t/unit-tests/generate-clar-decls.sh "${CMAKE_BINARY_DIR}/t/unit-tests/clar-decls.h" ${clar_test_SUITES}
>> +	DEPENDS ${CMAKE_SOURCE_DIR}/t/unit-tests/generate-clar-decls.sh ${clar_test_SUITES})
>> +add_custom_command(OUTPUT "${CMAKE_BINARY_DIR}/t/unit-tests/clar.suite"
>> +	COMMAND awk -f "${CMAKE_SOURCE_DIR}/t/unit-tests/clar-generate.awk" "${CMAKE_BINARY_DIR}/t/unit-tests/clar-decls.h" > "${CMAKE_BINARY_DIR}/t/unit-tests/clar.suite"
>> +	DEPENDS "${CMAKE_SOURCE_DIR}/t/unit-tests/clar-generate.awk" "${CMAKE_BINARY_DIR}/t/unit-tests/clar-decls.h")
>> +
>> +add_library(unit-tests-lib ${clar_test_SUITES}
>> +	"${CMAKE_SOURCE_DIR}/t/unit-tests/clar/clar.c"
>> +	"${CMAKE_BINARY_DIR}/t/unit-tests/clar-decls.h"
>> +	"${CMAKE_BINARY_DIR}/t/unit-tests/clar.suite"
>> +)
>>   target_include_directories(unit-tests-lib PUBLIC "${CMAKE_BINARY_DIR}/t/unit-tests")
>>   add_executable(unit-tests "${CMAKE_SOURCE_DIR}/t/unit-tests/unit-test.c")
>>   target_link_libraries(unit-tests unit-tests-lib common-main)
>> --
>> 2.47.0.72.gef8ce8f3d4.dirty
>>
>>
>