#!/bin/sh

search() {
  echo "$1"
  prefix="$(printf "%s\n" "$1"|sed 's|[^/]*$||')"
  deps="$(grep -E '^#include "[^"]*"$' "$1"|cut '-d"' -f2|
    \sed "s|^|$prefix|;s|\.h\$|.c|"|grep -v "^$1")"
  for i in $deps; do search $i; done
}

search "$1"|sort -u|grep -v "^$1"|sed 's|\.c$|.o|'