#!/usr/bin/sh

# Create a new file to be patched
binary=/usr/lib/systemd/systemd-volatile-root
target=/usr/lib/systemd/systemd-volatile-root.reliant-profiling
cp $binary $target

# We must NOP calls to umount and rmdir
hex_offsets=$(objdump -d "$binary" | grep -E 'call.*(umount|rmdir)' | awk '{ print $1 }' | tr -d ':')
for hex_offset in $hex_offsets; do
    dec_offset=$(perl -le "print hex(\"$hex_offset\")")
    printf '\x90\x90\x90\x90\x90' | dd of="$target" bs=1 seek=$dec_offset conv=notrunc
done

# Verify the patch has succeeded
for hex_offset in $hex_offsets; do
    echo -n "$hex_offset: "
    opcode=$(objdump -d "$target" | grep $hex_offset | awk '{ print $2 }')
    if [ "$opcode" -eq 90 ]; then
	echo "OK"
    else
	echo "FAIL"
    fi
done