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# rubocop:todo all
module Utils
extend self
# JRuby chokes when strings like "\xfe\x00\xff", which are not valid UTF-8,
# appear in the source. Use this method to build such strings.
# char_array is an array of byte values to use for the string.
def make_byte_string(char_array, encoding = 'BINARY')
char_array.map do |char|
char.chr.force_encoding('BINARY')
end.join.force_encoding(encoding)
end
# Forks the current process and executes the given block in the child.
# The value returned by the block is then returned in the parent process
# by this method.
#
# @return [ Object ] the value returned by the block
def perform_in_child(&block)
reader, writer = IO.pipe
if fork
parent_worker(reader, writer)
else
child_worker(reader, writer, &block)
end
end
private
# A utility method for #perform_in_child, to handle tasks for the parent
# side of the fork.
#
# @param [ IO ] reader The reader IO for the pipe
# @param [ IO ] writer The writer IO for the pipe
#
# @return [ Object ] the value returned by the child process
def parent_worker(reader, writer)
writer.close
blob = reader.read
reader.close
Process.wait
Marshal.load(blob)
end
# A utility method for #perform_in_child, to handle tasks for the child
# side of the fork.
#
# @param [ IO ] reader The reader IO for the pipe
# @param [ IO ] writer The writer IO for the pipe
def child_worker(reader, writer, &block)
reader.close
result = block.call
writer.write Marshal.dump(result)
writer.close
exit! 0
end
end
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