[pacman-dev] [PATCH] makepkg: canonicalize paths from environmental variables

[Dave Reisner]

On Mon, Oct 04, 2010 at 03:01:50PM +1000, Allan McRae wrote:
> This prevents circular symlinks and weird final package locations
> when using commands like  'PKGDEST="." makepkg'.
> 
> Fixes FS#20922.
> 
> Signed-off-by: Allan McRae <allan at archlinux.org>
> ---
>  scripts/makepkg.sh.in |   21 +++++++++++++++++----
>  1 files changed, 17 insertions(+), 4 deletions(-)
> 
> diff --git a/scripts/makepkg.sh.in b/scripts/makepkg.sh.in
> index 9bcd446..ccf4213 100644
> --- a/scripts/makepkg.sh.in
> +++ b/scripts/makepkg.sh.in
> @@ -1410,6 +1410,19 @@ run_split_packaging() {
>  	done
>  }
>  
> +# Canonicalize a path if it exists
> +canonicalize_path() {
> +	local path=$1;
> +
> +	if [[ -d $path ]]; then
> +		cd $path
> +		path=$(pwd)
> +		cd - &>/dev/null
> +	fi
> +
> +	echo $path
> +}
> +
>  # getopt like parser
>  parse_options() {
>  	local short_options=$1; shift;
> @@ -1615,10 +1628,10 @@ while true; do
>  	shift
>  done
>  
> -#preserve environment variables
> -_PKGDEST=${PKGDEST}
> -_SRCDEST=${SRCDEST}
> -_SRCPKGDEST=${SRCPKGDEST}
> +# preserve environment variables and canonicalize path
> +[[ -n ${PKGDEST} ]] && _PKGDEST=$(canonicalize_path ${PKGDEST})
> +[[ -n ${SRCDEST} ]] && _SRCDEST=$(canonicalize_path ${SRCDEST})
> +[[ -n ${SRCPKGDEST} ]] && _SRCPKGDEST=$(canonicalize_path ${SRCPKGDEST})
>  
>  # default config is makepkg.conf
>  MAKEPKG_CONF=${MAKEPKG_CONF:-$confdir/makepkg.conf}
> -- 
> 1.7.3.1
> 
> 
> 

Your cd inside the if needs quoting, and you can get away with just
referencing $PWD instead of forking to pwd (GNU coreutils just returns
$PWD anyways). However, using pwd might have an advantage. The -P flag
will resolve symlinks, and it seems to be common in other 'nixes. This
would solve the case of multiple nested symlinks.

d