Модуль: OS::Linux::Elf Приватный

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# File 'os/linux/elf/os.rb', line 11

def self.expand_elf_dst(str, ref, repl)
  # ELF gABI rules for DSTs:
  #   - Longest possible sequence using the rules (greedy).
  #   - Must start with a $ (enforced by caller).
  #   - Must follow $ with one underscore or ASCII [A-Za-z] (caller
  #     follows these rules for REF) or '{' (start curly quoted name).
  #   - Must follow first two characters with zero or more [A-Za-z0-9_]
  #     (enforced by caller) or '}' (end curly quoted name).
  # (from https://github.com/bminor/glibc/blob/41903cb6f460d62ba6dd2f4883116e2a624ee6f8/elf/dl-load.c#L182-L228)

  # In addition to capturing a token, also attempt to capture opening/closing braces and check that they are not
  # mismatched before expanding.
  str.gsub(/\$({?)([a-zA-Z_][a-zA-Z0-9_]*)(}?)/) do |orig_str|
    has_opening_brace = ::Regexp.last_match(1).present?
    matched_text = ::Regexp.last_match(2)
    has_closing_brace = ::Regexp.last_match(3).present?
    if (matched_text == ref) && (has_opening_brace == has_closing_brace)
      repl
    else
      orig_str
    end
  end
end