[pacman-dev] [PATCH 2/3] libmakepkg: use readelf instead of file for finding ELF file types

[Allan McRae]

On 27/11/19 7:29 am, Ethan Sommer wrote:
> Signed-off-by: Ethan Sommer <e5ten.arch at gmail.com>
> ---
>  scripts/libmakepkg/tidy/strip.sh.in | 26 ++++++++++++--------------
>  1 file changed, 12 insertions(+), 14 deletions(-)
> 

This diff is an absolute pain to read!

I went through all files on my system, and confirmed this change does
what it is supposed to.  Files are all stripped the same way.

Onto the issues Eli brought up:

1) Hiding errors from readelf.   If readelf errors in any way, we are
not going to be stripping the file anyway.  So I am fine with that.

2) Format of output.  I am OK with this given multiple implementations
use the same format, and we already rely on parsing the readelf output
when making debug packages.

In summmary.  Ack.

A

> diff --git a/scripts/libmakepkg/tidy/strip.sh.in b/scripts/libmakepkg/tidy/strip.sh.in
> index 1bd810f0..301d1989 100644
> --- a/scripts/libmakepkg/tidy/strip.sh.in
> +++ b/scripts/libmakepkg/tidy/strip.sh.in
> @@ -111,22 +111,20 @@ tidy_strip() {
>  
>  		local binary strip_flags
>  		find . -type f -perm -u+w -print0 2>/dev/null | while IFS= read -rd '' binary ; do
> -			case "$(file -bi "$binary")" in
> -				*application/x-sharedlib*)  # Libraries (.so)
> +			case "$(LC_ALL=C readelf -h "$binary" 2>/dev/null)" in
> +				*Type:*'DYN (Shared object file)'*) # Libraries (.so) or Relocatable binaries
>  					strip_flags="$STRIP_SHARED";;
> -				*application/x-archive*)    # Libraries (.a)
> -					strip_flags="$STRIP_STATIC";;
> -				*application/x-object*)
> -					case "$binary" in
> -						*.ko)                   # Kernel module
> -							strip_flags="$STRIP_SHARED";;
> -						*)
> -							continue;;
> -					esac;;
> -				*application/x-executable*) # Binaries
> +				*Type:*'EXEC (Executable file)'*) # Binaries
>  					strip_flags="$STRIP_BINARIES";;
> -				*application/x-pie-executable*)  # Relocatable binaries
> -					strip_flags="$STRIP_SHARED";;
> +				*Type:*'REL (Relocatable file)'*) # Libraries (.a) or objects
> +					if ar t "$binary" &>/dev/null; then # Libraries (.a)
> +						strip_flags="$STRIP_STATIC"
> +					elif [[ $binary = *'.ko' ]]; then # Kernel module
> +						strip_flags="$STRIP_SHARED"
> +					else
> +						continue
> +					fi
> +					;;
>  				*)
>  					continue ;;
>  			esac
>