rubyx/lib/elf/object_writer.rb
2020-03-26 11:24:33 +02:00

88 lines
2.5 KiB
Ruby

require_relative "stream_writer"
require_relative 'object_file'
require_relative 'symbol_table_section'
require_relative 'text_section'
require_relative 'string_table_section'
module Elf
class ObjectWriter
attr_reader :text
def initialize( linker , options = {} )
@linker = linker
target = Elf::Constants::TARGET_ARM
@object = Elf::ObjectFile.new(target)
sym_strtab = Elf::StringTableSection.new(".strtab")
@object.add_section sym_strtab
@symbol_table = Elf::SymbolTableSection.new(".symtab", sym_strtab)
@object.add_section @symbol_table
@text = Elf::TextSection.new(".text")
@object.add_section @text
assembler = Risc::TextWriter.new(@linker)
set_text assembler.write_as_string
add_debug_symbols(options)
end
# for debug add labels for labels
def add_debug_symbols(options)
debug = options[:debug]
return unless debug
@linker.assemblers.each do |asm|
meth = asm.callable
asm.instructions.each do |label|
next unless label.is_a?(Risc::Label)
add_symbol "#{meth.self_type.name}_#{meth.name}:Label=#{label.name}" , Risc::Position.get(label).at
end
meth.binary.each_block do |code|
label = "BinaryCode_#{meth.name}"
add_symbol label , Risc::Position.get(code).at
end
end
@linker.object_positions.each do |slot , position|
next if slot.is_a?(Parfait::BinaryCode)
next if slot.class.name.include?("Arm")
if( slot.respond_to? :rxf_reference_name )
label = "#{slot.rxf_reference_name}"
else
label = "#{slot.class.name}::#{Risc::Position.get(slot)}"
end
label += "=#{slot}" if slot.is_a?(Symbol) or slot.is_a?(String)
add_symbol label , Risc::Position.get(slot).at
end
end
def set_text(text)
@text.text = text
add_symbol "_start", 0
end
def add_symbol(name, offset, linkage = Elf::Constants::STB_GLOBAL)
return add_symbol( name + "_" , offset ) if @symbol_table.has_name(name)
@symbol_table.add_func_symbol name, offset, @text, linkage
end
# save to either file or io
# Pass Filename as string
# or any io object
def save(file)
case file
when String
io = File.open(file, 'wb')
when IO , StringIO
io = file
else
raise "must pass io or filename, not #{file}"
end
@object.write io
io.close
end
end
end