reuse.cr

require "socket"

class TCPServer
  def initialize(port, backlog = 128)
    @sock = C.socket(C::AF_INET, C::SOCK_STREAM, 0)

    optval = 1
    C.setsockopt(@sock, C::SOL_SOCKET, 2, pointerof(optval) as Void*, sizeof(Int32))

    addr = C::SockAddrIn.new
    addr.family = C::AF_INET
    addr.addr = 0_u32
    addr.port = C.htons(port)
    if C.bind(@sock, pointerof(addr), 16) != 0
      raise Errno.new("Error binding TCP server at #{port}")
    end

    if C.listen(@sock, backlog) != 0
      raise Errno.new("Error listening TCP server at #{port}")
    end
  end
end