You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: elf_decode.rb
    path of file: ./repos/grinder/node/lib/metasm/metasm/exe_format
    
    the code of the file until where you have to start completion: #    This file is part of Metasm, the Ruby assembly manipulation suite
#    Copyright (C) 2006-2009 Yoann GUILLOT
#
#    Licence is LGPL, see LICENCE in the top-level directory


require 'metasm/decode'
require 'metasm/exe_format/elf' unless defined? Metasm::ELF

module Metasm
class ELF
	class Header
		# hook the decode sequence, to fixup elf data based on info
		# we have (endianness & xword size, needed in decode_word etc)
		decode_hook(:type) { |elf, hdr|
			raise InvalidExeFormat, "E: ELF: invalid ELF signature #{hdr.magic.inspect}" if hdr.magic != "\x7fELF"

			case hdr.e_class
			when '32'; elf.bitsize = 32
			when '64', '64_icc'; elf.bitsize = 64
			else puts "W: ELF: unsupported class #{hdr.e_class}, assuming 32bit"; elf.bitsize = 32
			end

			case hdr.data
			when 'LSB'; elf.endianness = :little
			when 'MSB'; elf.endianness = :b
    
	def check_symbols_gnu_hash(off = @tag['GNU_HASH'], just_get_count=false)
		return if not @encoded.ptr = off

		# when present: the symndx first symbols are not sorted (SECTION/LOCAL/FILE/etc) symtable[symndx] is sorted (1st sorted symbol)
		# the sorted symbols are sorted by [gnu_hash_symbol_name(symbol.name) % hash_bucket_len]
		hash_bucket_len = decode_word
		symndx = decode_word		# index of first sorted symbol in symtab
		maskwords = decode_word		# number of words in the second part of the ghash section (32 or 64 bits)
		shift2 = decode_word		# used in the bloom filter

		bloomfilter = [] ; maskwords.times { bloomfilter << decode_xword }
		# "bloomfilter[N] has bit B cleared if there is no M (M > symndx) which satisfies (C = @header.class)
		# ((gnu_hash(sym[M].name) / C) % maskwords) == N	&&
		# ((gnu_hash(sym[M].name) % C) == B			||
		# ((gnu_hash(sym[M].name) >> shift2) % C) == B"
		# bloomfilter may be [~0]
		if shift2
		end