#!/bin/sh

REAL_NM=binutils-nm
PARENT="$(readlink /proc/$PPID/exe)"
WRAPPED=false

# If /proc isn't mounted, let's do the least evil thing we can
if [ -z "$PARENT" ]; then
	WRAPPED=true
# If we're being called by gcc-nm or llvm-nm, we're already
# wrapped (and need to make sure we don't call ourselves recursively)
elif echo "$PARENT" |grep -qE -- '-nm$'; then
	WRAPPED=true
# Fun... We're running inside qemu binfmt_misc emulation,
# so we have to determine our parent the evil and less
# reliable way...
elif echo "$PARENT" |grep -qE -- 'qemu'; then
	if grep -qE -- '-nm' /proc/$PPID/cmdline; then
		WRAPPED=true
    fi
fi

# If we're being called by gcc-nm or llvm-nm, we're
# already wrapped...
if ! "$WRAPPED"; then

	which llvm-nm &>/dev/null && IS_LLVM_NM=true
	which gcc-nm &>/dev/null && IS_GCC_NM=true
	[[ -z "$IS_GCC_NM" ]] && echo "${0}-wrapper ERROR: GCC-NM missing, cannot continue!" && exit 1
    for i in "$@"; do
		[ "$(echo $i |cut -b1)" = '-' ] && continue
		if echo "$i" |grep -qE '\.(o|a)$' && [ -e "$i" ]; then
			if LANG=C gcc-nm "$i" 2>&1 |grep -qi "file format not recognized"; then
				if [[ -n "$IS_LLVM_NM" ]]; then
					REAL_NM=llvm-nm
					break
				else
					echo "${0}-wrapper ERROR: LLVM-LTO code but missing llvm-nm, cannot continue!"
					exit 1
				fi
			fi

			if LANG=C readelf -s "$i" | grep -q "gnu_lto"; then
				# already checked
				REAL_NM=gcc-nm
				break
			fi
	fi
    done
fi
exec "$REAL_NM" "$@"