Đoàn Trần Công Danh <congdanhqx@xxxxxxxxx> writes:
> On 2020-08-14 10:26:24-0700, Junio C Hamano <gitster@xxxxxxxxx> wrote:
>> > Since both git-citool and git-gui will be installed into same
>> > directory "$(libexecdir)", I think it would make more sense to use:
>> >
>> > LN = ln -s
>> >
>> > here instead?
>>
>> In the top-level Makefile, INSTALL_SYMLINKS make macro does exist,
>> but it is not exported to submakes. If it were, something like
>>
>> ifdef INSTALL_SYMLINKS
>> LN = ln -s
>> else
>> ifdef NO_INSTALL_HARDLINKS
>> LN = cp
>> else
>> LN = ln
>> endif
>> endif
>>
>> might become possible, but you'd need to audit what is fed to $(LN)
>> at the locations the macro is used and make necessary adjustment
>> accordingly. "cp A ../B" or "ln A ../B" will make a usable copy of
>> file A appear inside ../B directory, but "ln -s A ../B" will not,
>> and I didn't see if all uses of $(LN) was to give synonyms to what
>> is already installed, or some of them were truly installing from the
>> build location when I gave the "something along this line" example.
>
> Yes, the top-level Makefile seems to have a special branch for
> BUILT_INS, in which, we will create symlink for those builtin in
> libexecdr if NO_INSTALL_HARDLINKS is defined.
Did you mean pieces like this?
for p in $(filter $(install_bindir_programs),$(BUILT_INS)); do \
$(RM) "$$bindir/$$p" && \
test -n "$(INSTALL_SYMLINKS)" && \
ln -s "git$X" "$$bindir/$$p" || \
{ test -z "$(NO_INSTALL_HARDLINKS)" && \
ln "$$bindir/git$X" "$$bindir/$$p" 2>/dev/null || \
ln -s "git$X" "$$bindir/$$p" 2>/dev/null || \
cp "$$bindir/git$X" "$$bindir/$$p" || exit; } \
done && \
The symlinks happen ONLY when INSTALL_SYMLINKS is asked for. Not
all filesystems support symbolic links, hardlinks never suffer from
dangling link problem, and often they are cheaper.
> I was aiming for something like this to make git-gui a bit more
> consistent with top-level Git, with or without INSTALL_SYMLINKS
> exported:
So with or without optional INSTALL_SYMLINKS exported, what I gave
you is what is the most consistent with the top-level, that is, if
INSTALL_SYMLINKS is there, we do "ln -s". Otherwise, we check
NO_INSTALL_HARDLINKS and we do either "ln" or "cp".
