Re: [PATCH 1/2] Makefile: Use the same source directory for "ln -s" as for "ln" / "cp"

From: Jeff King <peff@peff.net>
Date: Feb 5, 2015, 20:45 UTC
Message-ID: <20150205204534.GE15326@peff.net>
In-Reply-To: <CAHGBnuPL7NN9J+4xd7xifsmbSPcC5V2ze05ji7P_qnvWHPGV+A@mail.gmail.com>

On Thu, Feb 05, 2015 at 09:29:04PM +0100, Sebastian Schuberth wrote:

Show 26 quoted lines

> > We would still want an equivalent to 2/2 to set up a relative symlink
> > for $(ALL_PROGRAMS), though, right?
> 
> Probably. But I'm not sure how to calculate the relative path
> correctly so that it'll work with all possible bin / execdir
> combinations. A simple
> 
> diff --git a/Makefile b/Makefile
> index 21f23cb..d2849c3 100644
> 
> --- a/Makefile
> +++ b/Makefile
> 
> @@ -2258,8 +2258,8 @@
> 
>  endif
>  ········$(RM)·"$$execdir/$$p"·&&·\
>  ········test·-z·"$(NO_INSTALL_HARDLINKS)$(NO_CROSS_DIRECTORY_HARDLINKS)"·&&·\
>  ········ln·"$$bindir/$$p"·"$$execdir/$$p"·2>/dev/null·||·\
> +········ln·-s·"../$$p"·"$$execdir/$$p"·2>/dev/null·||·\
>  ········cp·"$$bindir/$$p"·"$$execdir/$$p"·||·exit;·\
>  ······done;·\
>  ····}·&&·\
> --·
> 
> does not seem to be correct in all cases.

Ah, I see. Yeah, you'd have to calculate that relative path between $bindir and $execdir. We have C code already to do that (see relative_path() in path.c), so in theory you could build a wrapper during the build phase and then run:

  ln -s $(./my-wrapper "$bindir" "$execdir")/$p $execdir/$p

or something during the install phase.

-Peff