Subject: Re: a problem with git describe

From: SZEDER Gábor <[email-masked]>
Date: Mon, 25 Apr 2022 07:05:49 +0200

On Sun, Apr 24, 2022 at 07:01:08PM -0700, Carlo Marcelo Arenas Belón wrote:
> On Sat, Apr 23, 2022 at 04:44:57PM -0700, Junio C Hamano wrote:
> > 
> > Actually, not quite.  when "git" runs in "sudo git", the real
> > identity has long lost
> 
> Right, but in this specific case, the terminal is still a good indication
> of who the user is, so the following would work.
> 
> diff --git a/git-compat-util.h b/git-compat-util.h
> index 58fd813bd01..5d5d91688ee 100644
> --- a/git-compat-util.h
> +++ b/git-compat-util.h
> @@ -442,6 +442,11 @@ static inline int is_path_owned_by_current_uid(const char *path)
>  	struct stat st;
>  	if (lstat(path, &st))
>  		return 0;
> +	if (isatty(1)) {
> +		struct stat ttyst;
> +		if (!stat(ttyname(1), &ttyst))
> +			return st.st_uid == ttyst.st_uid;
> +	}
>  	return st.st_uid == geteuid();
>  }

Our 'GIT-VERSION-GEN' runs 'var=$(git describe ...)', so standard
output is not a terminal during 'sudo make install'

> It obviously needs more polishing and portability work, though, and I don't
> like that it makes the general case more complicated, so maybe would be better
> to only do it running as root?
> 
> At that point, though you might as well excempt root from this check
> 
> Carlo