#! /usr/local/bin/python --

"""
usage: %(progname)s [args]
"""

import bisect
import os
import select
import socket
import string
import sys
import time
import whrandom

import coro
import fcntl, FCNTL



class coroutine_device:
	"socket that automatically suspends/resumes instead of blocking."

	def __init__ (self, _fileno=None):
	  self._fileno = _fileno
	  self._closed = 0

	  if self._fileno:
	    flags = fcntl.fcntl(self._fileno, FCNTL.F_GETFL, 0)
	    fcntl.fcntl(self._fileno, FCNTL.F_SETFL, flags | FCNTL.O_NONBLOCK)

	def fileno (self):
	  return self._fileno

	TimeoutError = coro.TimeoutError

	def wait_for_read (self, timeout=None):
	  me = coro.current_thread()
	  if timeout is not None:
	    triple = coro.the_event_list.insert_event (me, time.time()+timeout, TIMEOUT_VALUE)
	  if me is None:
	    raise coro.CoroutineSocketError, "coroutine sockets cannot run in 'main'"
	  else:
	    coro.read_set[self._fileno] = me
	    try:
	      result = me.yield_()
	    except:
	      raise coro.CoroutineSocketError, "coroutine socket could not yield_"
	    if result == coro.TIMEOUT_VALUE:
	      # i.e, we timed out
	      del coro.read_set[self._fileno]
	      raise TimeoutError
	    elif timeout is not None:
	      try:
		# remove event
		coro.the_event_list.remove_event (triple)
	      except:
		print "Error removing: result=%s" % result
	    if result == coro.BADF_ERROR:
	      # ie, bad socket for select
	      raise coro.CoroutineSocketError, "bad file descriptor"

	def wait_for_write (self, timeout=None):
	  me = coro.current_thread()
	  if timeout is not None:
	    triple = coro.the_event_list.insert_event (me, time.time()+timeout, TIMEOUT_VALUE)
	  if me is None:
	    raise coro.CoroutineSocketError, "coroutine sockets cannot run in 'main'"
	  else:
	    coro.write_set[self._fileno] = me
	    try:
	      result = me.yield_()
	    except:
	      raise coro.CoroutineSocketError, "coroutine socket could not yield_"
	    if result == coro.TIMEOUT_VALUE:
	      # i.e, we timed out
	      del coro.write_set[self._fileno]
	      raise TimeoutError
	    elif timeout is not None:
	      # remove event
	      coro.the_event_list.remove_event (triple)
	    if result == coro.BADF_ERROR:
	      # ie, bad socket for select
	      raise coro.CoroutineSocketError, "bad file descriptor"

	def read(self, buffer_size):
	  self.wait_for_read()
	  return os.read(self._fileno, buffer_size)

	def write(self, data):
	  self.wait_for_write()
	  return os.write(self._fileno, data)


	def close (self):
	  if not self._closed:
	    self._closed = 1
	    if self._fileno:
	      return os.close(self._fileno)
	    else:
	      return None

	def __del__ (self):
	  self.close()