Fw: Aw: Re: git equivalent to pulling the most recent date from ChangeLog?

[Bastian M. <bma...@we...>]

Forgot to reply to the list.

> > On Monday, 25 December 2017 22:08:24 Bastian Märkisch wrote:
> > > > Building from git tip fails to insert a valid date into
> > > > the "last modified" field.   This used to be pulled from the
> > > > top of ChangeLog and inserted into timestamp.h but that 
> > > > mechanism does not track the date of git commits.
> > > 
> > > That might do the trick:
> > >   git log -1 --format=%ci | cut -b-10
> > > 
> > >   Bastian
> > 
> > That looks promising.
> > Can someone wrap that in the appropriate Makefile syntax to
> > substitute for the rule currently in src/Makefile.am?
> > 
> > timestamp.h: $(top_srcdir)/ChangeLog Makefile
> >         @echo Making $@
> >         @echo "#ifndef GNUPLOT_TIMEBASE_H_INCLUDED" >$@t
> >         @echo "#define GNUPLOT_TIMEBASE_H_INCLUDED" >>$@t
> >         @head -1 $< | sed -e 's,\(^[0-9-]* \).*$$,const char gnuplot_date[] = "\1";,' >>$@t
> >         @echo "#endif /* GNUPLOT_TIMEBASE_H_INCLUDED */" >> $@t
> >         @if cmp -s $@ $@t; then rm -f $@t; else mv $@t $@; fi
> > 
> > 
> > 
> > I suppose the dependency rule would become something like
> > 
> > timestamp.h: $(top_srcdir)/.git/objects Makefile
> > 
> > but how does one get "make" to track the change status of .git/objects ?
> > 
> > 	Ethan
> 
> 
> Pleae find below my attempt on a solution.  Note that the dependency
> "trick" is taken from 
> http://www.howtobuildsoftware.com/index.php/how-do/ceio/git-makefile-hook-track-branch-changes-from-a-makefile
> 
>   Bastian
> 
> diff --git a/src/Makefile.am b/src/Makefile.am
> index 0af79fe..9c57550 100644
> --- a/src/Makefile.am
> +++ b/src/Makefile.am
> @@ -105,11 +105,12 @@ endif
>  
>  DISTCLEANFILES = timestamp.h
>  BUILT_SOURCES = timestamp.h
> -timestamp.h: $(top_srcdir)/ChangeLog Makefile
> +git_current := $(shell cut -c6- $(top_srcdir)/.git/HEAD)
> +timestamp.h: $(top_srcdir)/.git/${git_current} Makefile
>         @echo Making $@
>         @echo "#ifndef GNUPLOT_TIMEBASE_H_INCLUDED" >$@t
>         @echo "#define GNUPLOT_TIMEBASE_H_INCLUDED" >>$@t
> -       @head -1 $< | sed -e 's,\(^[0-9-]* \).*$$,const char gnuplot_date[] = "\1";,' >>$@t
> +       @echo "const char gnuplot_date[] = \"`git log -1 --format=%ci | cut -b-11`\";" >>$@t
>         @echo "#endif /* GNUPLOT_TIMEBASE_H_INCLUDED */" >> $@t
>         @if cmp -s $@ $@t; then rm -f $@t; else mv $@t $@; fi
>