class GDB

# File bin/gdbruby.rb, line 114
def initialize(config)
  @config = config
  @exec_options = ['gdb', '-silent', '-nw', @config.exe, @config.core_or_pid]
end

# File bin/gdbruby.rb, line 158
def cmd_exec(cmd)
  log_gdb('C', cmd)
  if cmd
    send_cmd = cmd.empty? ? cmd : "#{cmd}\n"
    r = @gdb_stdin.syswrite(send_cmd)
    if r < send_cmd.length
      raise "failed to send: [#{cmd}]"
    end
  end

  responses = []
  while true
    # TODO: specify buffer size
    begin
      buf = @gdb_stdout.sysread(COMMAND_READ_BUFFER_SIZE)
    rescue
      break
    end
    responses << buf
    break if buf =~ /\(gdb\) $/
  end

  response = responses.join('')
  log_gdb('R', response)
  response
end

# File bin/gdbruby.rb, line 152
def cmd_get_pointer(cmd, type)
  response = cmd_exec(cmd)
  raise "Invalid pointer #{response}" unless response =~ /\(#{type} \*\) (0x[0-9a-f]+)/
  $1
end

# File bin/gdbruby.rb, line 185
def cmd_get_value(cmd)
  response = cmd_exec(cmd)
  return '' unless response =~ /\A\$\d+ =\s+(.+)/

  value = $1
  if value =~ /0x\w+\s+\"(.+)\"/
    $1
  else
    value
  end
end

# File bin/gdbruby.rb, line 140
def detach
  cmd_get_value("detach")
  cmd_get_value("quit")
end

# File bin/gdbruby.rb, line 145
def log_gdb(pre, message)
  return unless @config['verbose_gdb', false]
  message.each_line do |line|
    puts "#{pre}: #{line}"
  end
end

# File bin/gdbruby.rb, line 135
def prepare
  cmd_exec('')
  cmd_exec('set pagination off')
end

# File bin/gdbruby.rb, line 119
def run
  @gdb_stdin, @gdb_stdout, @gdb_stderr = *Open3.popen3(*@exec_options)
  prepare
  begin
    yield
    detach
  ensure
    if @config.is_pid
      Process.kill('CONT', @config.core_or_pid.to_i)
    end
    @gdb_stdin.close
    @gdb_stdout.close
    @gdb_stderr.close
  end
end