48 lines
1.3 KiB
Ruby
48 lines
1.3 KiB
Ruby
require 'elf/object_file'
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require 'elf/symbol_table_section'
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require 'elf/text_section'
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require 'elf/string_table_section'
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module Elf
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class ObjectWriter
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def initialize(program , target)
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@object = Elf::ObjectFile.new(target)
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@program = program
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sym_strtab = Elf::StringTableSection.new(".strtab")
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@object.add_section sym_strtab
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@symbol_table = Elf::SymbolTableSection.new(".symtab", sym_strtab)
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@object.add_section @symbol_table
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@text = Elf::TextSection.new(".text")
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@object.add_section @text
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program.link_at( 0 , program.context )
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binary = program.assemble(StringIO.new )
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blocks = []
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program.functions.each {|f| blocks += f.blocks }
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blocks += [program.entry , program.exit , program.main]
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blocks.flatten.each do |b|
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add_symbol b.name.to_s , b.position
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end
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set_text binary.string
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end
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attr_reader :text
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def set_text(text)
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@text.text = text
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add_symbol "_start", 0
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end
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def add_symbol(name, offset, linkage = Elf::Constants::STB_GLOBAL)
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@symbol_table.add_func_symbol name, offset, @text, linkage
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end
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def save(filename)
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to = File.open(filename, 'wb')
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@object.write to
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to.close
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end
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end
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end |