Re: [PATCH v5] Allow to build and run sign/digest on Windows

[Eric Biggers <ebiggers@kernel.org>]

On Mon, Dec 21, 2020 at 10:19:53PM +0000, Luca Boccassi wrote:
> From: Luca Boccassi <luca.boccassi@microsoft.com>
> 
> stub out the enable/measure sources.

That's not the case anymore, right?  Now those files are just omitted.

> diff --git a/Makefile b/Makefile
> index bfe83c4..d850ae3 100644
> --- a/Makefile
> +++ b/Makefile
> @@ -35,6 +35,11 @@
>  cc-option = $(shell if $(CC) $(1) -c -x c /dev/null -o /dev/null > /dev/null 2>&1; \
>  	      then echo $(1); fi)
>  
> +# Support building with MinGW for minimal Windows fsverity.exe
> +ifneq ($(findstring -mingw,$(shell $(CC) -dumpmachine 2>/dev/null)),)
> +MINGW = 1
> +endif

It would be helpful if this comment mentioned that libfsverity isn't built as a
proper Windows library.  At the moment it is not very clear.

Also, a note in the README about the Windows support would be helpful.

> -override CPPFLAGS := -Iinclude -D_FILE_OFFSET_BITS=64 $(CPPFLAGS)
> +override CPPFLAGS := -Iinclude -D_FILE_OFFSET_BITS=64 -D_GNU_SOURCE $(CPPFLAGS)

The _GNU_SOURCE change should go in a separate patch.

>  # Rebuild if a user-specified setting that affects the build changed.
>  .build-config: FORCE
> @@ -87,9 +97,9 @@ CFLAGS          += $(shell "$(PKGCONF)" libcrypto --cflags 2>/dev/null || echo)
>  # If we are dynamically linking, when running tests we need to override
>  # LD_LIBRARY_PATH as no RPATH is set
>  ifdef USE_SHARED_LIB
> -RUN_FSVERITY    = LD_LIBRARY_PATH=./ ./fsverity
> +RUN_FSVERITY    = LD_LIBRARY_PATH=./ $(TEST_WRAPPER_PROG) ./fsverity$(EXEEXT)
>  else
> -RUN_FSVERITY    = ./fsverity
> +RUN_FSVERITY    = $(TEST_WRAPPER_PROG) ./fsverity$(EXEEXT)
>  endif

Adding $(TEST_WRAPPER_PROG) here should go in a separate patch too.  It also
affects valgrind testing on Linux.

>  # Link the fsverity program
>  ifdef USE_SHARED_LIB
> -fsverity: $(FSVERITY_PROG_OBJ) libfsverity.so
> +fsverity$(EXEEXT): $(FSVERITY_PROG_OBJ) libfsverity.so

It would be easier to read if there was a variable $(FSVERITY) that had the
value of fsverity$(EXEEXT).

>  # Link the test programs
>  $(TEST_PROGRAMS): %: programs/%.o $(PROG_COMMON_OBJ) libfsverity.a
> @@ -184,25 +200,25 @@ test_programs:$(TEST_PROGRAMS)

This still doesn't actually add the .exe extension to the test programs.
Try 'make CC=x86_64-w64-mingw32-gcc help'; the targets to build the test
programs don't have the .exe extension.

- Eric