X-Git-Url: https://git.ucc.asn.au/?p=zanchey%2Fdispense2.git;a=blobdiff_plain;f=sql-edition%2Fservers%2FVendingMachine.py;h=9fe524519e7666579c09245f6110fbcc0050fe24;hp=2574c6d36a23ffc9c82adb62200df5d30ebbae3c;hb=753f7f6d9b81b406cdb9b5d48fbbf2005fead1a7;hpb=01c3723145f0bfb635fea3c3a254859e396e3e2a

diff --git a/sql-edition/servers/VendingMachine.py b/sql-edition/servers/VendingMachine.py
index 2574c6d..9fe5245 100644
--- a/sql-edition/servers/VendingMachine.py
+++ b/sql-edition/servers/VendingMachine.py
@@ -1,4 +1,5 @@
-import re, pg
+# vim:ts=4
+import re
 from CRC import do_crc
 from select import select
 
@@ -11,6 +12,8 @@ DOOR = 1
 SWITCH = 2
 KEY = 3
 
+class VendingException(Exception): pass
+
 class VendingMachine:
 	def __init__(self, rfh, wfh):
 		self.events = []
@@ -26,7 +29,7 @@ class VendingMachine:
 		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):
@@ -35,8 +38,12 @@ class VendingMachine:
 		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 = ''
@@ -49,7 +56,7 @@ class VendingMachine:
 					self.challenge = int(prefix, 16)
 					return
 
-	def get_response(self):
+	def get_response(self, async = False):
 		self.wfh.flush()
 		while True:
 			s = ''
@@ -61,6 +68,7 @@ class VendingMachine:
 			text = s[4:]
 			if code in asynchronous_responses:
 				self.handle_event(code, text)
+				if async: return None
 			else:
 				self.await_prompt()
 				return (code, text)
@@ -82,7 +90,7 @@ class VendingMachine:
 		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])))
@@ -129,8 +137,7 @@ class VendingMachine:
 			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:
@@ -139,18 +146,18 @@ class VendingMachine:
 		(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