-import re, pg
+# vim:ts=4
+import re
from CRC import do_crc
from select import select
SWITCH = 2
KEY = 3
+class VendingException(Exception): pass
+
class VendingMachine:
def __init__(self, rfh, wfh):
self.events = []
self.wfh.write('PING\n')
code = ''
while code != '000':
- (code, _) = self.get_response()
+ code = self.get_response()[0]
self.get_switches()
def await_prompt(self):
prefix = ''
s = ''
while True:
- s = self.rfh.read(1)
- if s == '': raise Exception
+ try:
+ s = self.rfh.read(1)
+ except socket.error:
+ print "Blah, seems DEC server has fallen over"
+ raise VendingException('failed to read input from vending machine')
+ if s == '': raise VendingException('nothing read!')
if s == '\n' or s == '\r':
state = 1
prefix = ''
self.challenge = int(prefix, 16)
return
- def get_response(self):
+ def get_response(self, async = False):
self.wfh.flush()
while True:
s = ''
while s == '':
s = self.rfh.readline()
- if s == '': return None
+ if s == '':
+ raise VendingException('Input socket has closed!')
s = s.strip('\r\n')
code = s[0:3]
text = s[4:]
if code in asynchronous_responses:
self.handle_event(code, text)
+ if async: return None
else:
self.await_prompt()
return (code, text)
elif code == '401':
self.events.append((DOOR, 1))
elif code == '610':
- self.events_append((SWITCH, None))
+ self.events.append((SWITCH, None))
self.interpret_switches(text)
elif code[0] == '2':
self.events.append((KEY, int(code[1:3])))
msg += '%02x'%duration
self.wfh.write(msg+'\n')
(code, string) = self.get_response()
- # FIXME: workaround a bug in rom W. should be just: return (code == '500', code, string)
- return (code == '500' or code == '501', code, string)
+ return (code == '501', code, string)
def display(self, string):
if len(string) > 10:
(code, string) = self.get_response()
return (code == '300', code, string)
- def next_event(self):
- if len(self.events) > 0:
- ret = self.events[0]
- del self.events[0]
- return ret
- return None
-
- def wait_for_events(self, timeout = None):
- (r, _, _) = select([self.rfh], [], [], timeout)
- if not r: return False
- event_added = False
+ def next_event(self, timeout = None):
+ # we don't want to buffer in the serial port, so we get all the events
+ # we can ASAP.
+ if len(self.events) > 0: timeout = 0
while True:
- r.get_response()
- (r, _, _) = select([self.rfh], [], [], 0)
- if not r: return event_added
+ (r, _, _) = select([self.rfh], [], [], timeout)
+ if r:
+ self.get_response(async = True)
+ timeout = 0
+ else:
+ break
+ if len(self.events) == 0: return None
+ ret = self.events[0]
+ del self.events[0]
+ return ret