Automatically find a free display

This commit is contained in:
Marco Pesenti Gritti 2006-07-15 15:32:05 +02:00
parent 21b46a0022
commit faac100ba5

View File

@ -1,20 +1,46 @@
import logging
import os
import socket
from Process import Process
class XephyrProcess(Process):
def __init__(self):
# FIXME How to pick a free display number?
self._display = 100
self._display = self.get_display_number()
cmd = 'Xephyr :%d -ac -screen 640x480' % (self._display)
Process.__init__(self, cmd)
def get_display_number(self):
"""Find a free display number trying to connect to 6000+ sockets"""
retries = 20
display_number = 1
display_is_free = False
while not display_is_free and retries > 0:
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
try:
s.connect(('127.0.0.1', 6000 + display_number))
logging.info('Display %d is already in use. Trying next.' % (display_number))
display_number += 1
retries -= 1
except:
display_is_free = True
if display_is_free:
return display_number
return -1
def get_name(self):
return 'Xephyr'
def start(self):
Process.start(self)
os.environ['DISPLAY'] = ":%d" % (self._display)
if self._display < 0:
logging.error('Cannot find a free display.')
else:
Process.start(self)
os.environ['DISPLAY'] = ":%d" % (self._display)
class Emulator:
"""The OLPC emulator"""