RE: [PATCH v2 07/12] fsmonitor: prepare to share code between Mac OS and Linux

From: Eric DeCosta <edecosta@mathworks.com>
Date: Oct 17, 2022, 21:30 UTC
Message-ID: <BL0PR05MB557147E13EFF24F664A14832D9299@BL0PR05MB5571.namprd05.prod.outlook.com>
In-Reply-To: <xmqqmt9y55py.fsf@gitster.g>

Show 55 quoted lines

> -----Original Message-----
> From: Junio C Hamano <gitster@pobox.com>
> Sent: Friday, October 14, 2022 7:46 PM
> To: Eric DeCosta via GitGitGadget <gitgitgadget@gmail.com>
> Cc: git@vger.kernel.org; Eric Sunshine <sunshine@sunshineco.com>; Ævar
> Arnfjörð Bjarmason <avarab@gmail.com>; Eric DeCosta
> <edecosta@mathworks.com>
> Subject: Re: [PATCH v2 07/12] fsmonitor: prepare to share code between
> Mac OS and Linux
> 
> "Eric DeCosta via GitGitGadget" <gitgitgadget@gmail.com> writes:
> 
> >  ifdef FSMONITOR_DAEMON_BACKEND
> >  	COMPAT_CFLAGS += -DHAVE_FSMONITOR_DAEMON_BACKEND
> > +	ifdef FSMONITOR_DAEMON_COMMON
> > +		COMPAT_OBJS += compat/fsmonitor/fsm-ipc-
> $(FSMONITOR_DAEMON_COMMON).o
> > +	else
> > +		COMPAT_OBJS += compat/fsmonitor/fsm-ipc-
> $(FSMONITOR_DAEMON_BACKEND).o
> > +	endif
> >  	COMPAT_OBJS += compat/fsmonitor/fsm-listen-
> $(FSMONITOR_DAEMON_BACKEND).o
> >  	COMPAT_OBJS += compat/fsmonitor/fsm-health-
> $(FSMONITOR_DAEMON_BACKEND).o
> > -	COMPAT_OBJS += compat/fsmonitor/fsm-ipc-
> $(FSMONITOR_DAEMON_BACKEND).o
> >  endif
> >
> >  ifdef FSMONITOR_OS_SETTINGS
> >  	COMPAT_CFLAGS += -DHAVE_FSMONITOR_OS_SETTINGS
> > +	ifdef FSMONITOR_DAEMON_COMMON
> > +		COMPAT_OBJS += compat/fsmonitor/fsm-settings-
> $(FSMONITOR_DAEMON_COMMON).o
> > +	endif
> >  	COMPAT_OBJS += compat/fsmonitor/fsm-settings-
> $(FSMONITOR_OS_SETTINGS).o
> >  	COMPAT_OBJS +=
> > compat/fsmonitor/fsm-path-utils-$(FSMONITOR_OS_SETTINGS).o
> >  endif
> 
> Ugly.
> 
> One overrides backend with common, while the other one doesn't.
> That asymmetry alone should stop us and wonder if there is something fishy
> in the approach that can be improved.  It makes it look like the word
> "common" means something quite different between the -ipc and the -
> settings world.
> 
> I suspect that in both, you should not expose "unix" to this part of the
> Makefile.  Linux and macOS occasionally being similar in some places does
> not have to be exposed here.  INstead you can use backend "linux" and
> "macos", whose C sources may include from a separate C source file whose
> name may contain "unix".  That would allow you to get rid of
> FSMONITOR_DAEMON_COMMON in a cleaner way.

Let me see if I am understanding you correctly. Are you suggesting something like:

ifdef FSMONITOR_DAEMON_BACKEND_LINUX
	COMPAT_CFLAGS += -DHAVE_FSMONITOR_DAEMON_BACKEND
	COMPAT_OBJS += compat/fsmonitor/fsm-ipc-unix.o
	COMPAT_OBJS += compat/fsmonitor/fsm-ipc-$(FSMONITOR_DAEMON_BACKEND_LINUX).o
	COMPAT_OBJS += compat/fsmonitor/fsm-listen-$(FSMONITOR_DAEMON_BACKEND_LINUX).o
	COMPAT_OBJS += compat/fsmonitor/fsm-health-$(FSMONITOR_DAEMON_BACKEND_LINUX).o
endif

ifdef FSMONITOR_DAEMON_BACKEND_DARWIN
	COMPAT_CFLAGS += -DHAVE_FSMONITOR_DAEMON_BACKEND
	COMPAT_OBJS += compat/fsmonitor/fsm-ipc-unix.o
	COMPAT_OBJS += compat/fsmonitor/fsm-ipc-$(FSMONITOR_DAEMON_BACKEND_DARWIN).o
	COMPAT_OBJS += compat/fsmonitor/fsm-listen-$(FSMONITOR_DAEMON_BACKEND_DARWIN).o
	COMPAT_OBJS += compat/fsmonitor/fsm-health-$(FSMONITOR_DAEMON_BACKEND_DARWIN).o
endif

And similarly for settings:

ifdef FSMONITOR_DAEMON_SETTINGS_LINUX
	COMPAT_CFLAGS += -DHAVE_FSMONITOR_OS_SETTINGS
	COMPAT_OBJS += compat/fsmonitor/fsm-settings-unix.o
	COMPAT_OBJS += compat/fsmonitor/fsm-settings-$(FSMONITOR_DAEMON_SETTINGS_LINUX).o
	COMPAT_OBJS += compat/fsmonitor/fsm-path-utils-$(FSMONITOR_DAEMON_SETTINGS_LINUX).o
endif

ifdef FSMONITOR_DAEMON_SETTINGS_DARWIN
	COMPAT_CFLAGS += -DHAVE_FSMONITOR_OS_SETTINGS
	COMPAT_OBJS += compat/fsmonitor/fsm-settings-unix.o
	COMPAT_OBJS += compat/fsmonitor/fsm-settings-$(FSMONITOR_DAEMON_SETTINGS_DARWIN).o
	COMPAT_OBJS += compat/fsmonitor/fsm-path-utils-$(FSMONITOR_DAEMON_SETTINGS_DARWIN).o
endif

And the rest of the platforms remain as was, with FSMONITOR_DAEMON_BACKEND and FSMONITOR_OS_SETTINGS

-Eric