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tea4cups @ 631

Revision 631, 41.4 kB (checked in by jerome, 19 years ago)
Improved the IPP parser
Property svn:executable set to ``* Property svn:keywords set to `Author Date Id Rev`

Rev	Line
[565]	1	#! /usr/bin/env python
	2	# -- coding: ISO-8859-15 --
	3
[576]	4	# Tea4CUPS : Tee for CUPS
[565]	5	#
	6	# (c) 2005 Jerome Alet <alet@librelogiciel.com>
	7	# This program is free software; you can redistribute it and/or modify
	8	# it under the terms of the GNU General Public License as published by
	9	# the Free Software Foundation; either version 2 of the License, or
	10	# (at your option) any later version.
	11	#
	12	# This program is distributed in the hope that it will be useful,
	13	# but WITHOUT ANY WARRANTY; without even the implied warranty of
	14	# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	15	# GNU General Public License for more details.
	16	#
	17	# You should have received a copy of the GNU General Public License
	18	# along with this program; if not, write to the Free Software
	19	# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307, USA.
	20	#
	21	# $Id$
	22	#
	23	#
	24
	25	import sys
	26	import os
[630]	27	import pwd
[584]	28	import popen2
[568]	29	import errno
[577]	30	import md5
[565]	31	import cStringIO
	32	import shlex
[568]	33	import tempfile
[570]	34	import ConfigParser
[588]	35	import select
	36	import signal
	37	import time
[581]	38	from struct import unpack
[565]	39
[630]	40	version = "2.12alpha_unofficial"
[585]	41
[570]	42	class TeeError(Exception):
[576]	43	"""Base exception for Tea4CUPS related stuff."""
[570]	44	def __init__(self, message = ""):
	45	self.message = message
	46	Exception.__init__(self, message)
	47	def __repr__(self):
	48	return self.message
	49	__str__ = __repr__
	50
	51	class ConfigError(TeeError) :
	52	"""Configuration related exceptions."""
	53	pass
	54
[581]	55	class IPPError(TeeError) :
	56	"""IPP related exceptions."""
	57	pass
	58
[584]	59	class Popen4ForCUPS(popen2.Popen4) :
	60	"""Our own class to execute real backends.
	61
	62	Their first argument is different from their path so using
	63	native popen2.Popen3 would not be feasible.
	64	"""
	65	def __init__(self, cmd, bufsize=-1, arg0=None) :
	66	self.arg0 = arg0
	67	popen2.Popen4.__init__(self, cmd, bufsize)
	68
	69	def _run_child(self, cmd):
	70	try :
	71	MAXFD = os.sysconf("SC_OPEN_MAX")
	72	except (AttributeError, ValueError) :
	73	MAXFD = 256
	74	for i in range(3, MAXFD) :
	75	try:
	76	os.close(i)
	77	except OSError:
	78	pass
	79	try:
	80	os.execvpe(cmd[0], [self.arg0 or cmd[0]] + cmd[1:], os.environ)
	81	finally:
	82	os._exit(1)
	83
[582]	84	# Some IPP constants
	85	OPERATION_ATTRIBUTES_TAG = 0x01
	86	JOB_ATTRIBUTES_TAG = 0x02
	87	END_OF_ATTRIBUTES_TAG = 0x03
	88	PRINTER_ATTRIBUTES_TAG = 0x04
	89	UNSUPPORTED_ATTRIBUTES_TAG = 0x05
	90
[581]	91	class IPPMessage :
	92	"""A class for IPP message files."""
[631]	93	def __init__(self, data, debug=0) :
[581]	94	"""Initializes an IPP Message object."""
[631]	95	self.debug = debug
[581]	96	self.data = data
[631]	97	self.operation_attributes = {}
	98	self.job_attributes = {}
	99	self.printer_attributes = {}
[581]	100	self.tags = [ None ] * 256 # by default all tags reserved
	101
	102	# Delimiter tags
	103	self.tags[0x01] = "operation-attributes-tag"
	104	self.tags[0x02] = "job-attributes-tag"
	105	self.tags[0x03] = "end-of-attributes-tag"
	106	self.tags[0x04] = "printer-attributes-tag"
	107	self.tags[0x05] = "unsupported-attributes-tag"
	108
	109	# out of band values
	110	self.tags[0x10] = "unsupported"
	111	self.tags[0x11] = "reserved-for-future-default"
	112	self.tags[0x12] = "unknown"
	113	self.tags[0x13] = "no-value"
	114
	115	# integer values
	116	self.tags[0x20] = "generic-integer"
	117	self.tags[0x21] = "integer"
	118	self.tags[0x22] = "boolean"
	119	self.tags[0x23] = "enum"
	120
	121	# octetString
	122	self.tags[0x30] = "octetString-with-an-unspecified-format"
	123	self.tags[0x31] = "dateTime"
	124	self.tags[0x32] = "resolution"
	125	self.tags[0x33] = "rangeOfInteger"
	126	self.tags[0x34] = "reserved-for-collection"
	127	self.tags[0x35] = "textWithLanguage"
	128	self.tags[0x36] = "nameWithLanguage"
	129
	130	# character strings
	131	self.tags[0x20] = "generic-character-string"
	132	self.tags[0x41] = "textWithoutLanguage"
	133	self.tags[0x42] = "nameWithoutLanguage"
	134	# self.tags[0x43] = "reserved"
	135	self.tags[0x44] = "keyword"
	136	self.tags[0x45] = "uri"
	137	self.tags[0x46] = "uriScheme"
	138	self.tags[0x47] = "charset"
	139	self.tags[0x48] = "naturalLanguage"
	140	self.tags[0x49] = "mimeMediaType"
	141
	142	# now parses the IPP message
	143	self.parse()
	144
	145	def parseTag(self) :
	146	"""Extracts information from an IPP tag."""
	147	pos = self.position
	148	valuetag = self.tags[ord(self.data[pos])]
	149	pos += 1
	150	posend = pos2 = pos + 2
	151	namelength = unpack(">H", self.data[pos:pos2])[0]
	152	if not namelength :
[631]	153	name = self._curname
[581]	154	else :
	155	posend += namelength
[631]	156	self._curname = name = self.data[pos2:posend]
[581]	157	pos2 = posend + 2
	158	valuelength = unpack(">H", self.data[posend:pos2])[0]
	159	posend = pos2 + valuelength
	160	value = self.data[pos2:posend]
[631]	161	oldval = self._curdict.setdefault(name, [])
	162	oldval.append((valuetag, value))
	163	self.printInfo("%s(%s) %s" % (name, valuetag, value))
[581]	164	return posend - self.position
	165
	166	def operation_attributes_tag(self) :
	167	"""Indicates that the parser enters into an operation-attributes-tag group."""
[631]	168	self.printInfo("Start of operation_attributes_tag")
	169	self._curdict = self.operation_attributes
[581]	170	return self.parseTag()
	171
	172	def job_attributes_tag(self) :
[631]	173	"""Indicates that the parser enters into an operation-attributes-tag group."""
	174	self.printInfo("Start of job_attributes_tag")
	175	self._curdict = self.job_attributes
[581]	176	return self.parseTag()
	177
	178	def printer_attributes_tag(self) :
[631]	179	"""Indicates that the parser enters into an operation-attributes-tag group."""
	180	self.printInfo("Start of printer_attributes_tag")
	181	self._curdict = self.printer_attributes
[581]	182	return self.parseTag()
	183
[631]	184	def printInfo(self, msg) :
	185	"""Prints a debug message."""
	186	if self.debug :
	187	sys.stderr.write("%s\n" % msg)
	188	sys.stderr.flush()
	189
[581]	190	def parse(self) :
	191	"""Parses an IPP Message.
	192
	193	NB : Only a subset of RFC2910 is implemented.
	194	We are only interested in textual informations for now anyway.
	195	"""
[631]	196	self._curname = None
	197	self._curdict = None
[581]	198	self.version = "%s.%s" % (ord(self.data[0]), ord(self.data[1]))
	199	self.operation_id = "0x%04x" % unpack(">H", self.data[2:4])[0]
	200	self.request_id = "0x%08x" % unpack(">I", self.data[4:8])[0]
	201	self.position = 8
	202	try :
	203	tag = ord(self.data[self.position])
	204	while tag != END_OF_ATTRIBUTES_TAG :
	205	self.position += 1
	206	name = self.tags[tag]
	207	if name is not None :
	208	func = getattr(self, name.replace("-", "_"), None)
	209	if func is not None :
	210	self.position += func()
	211	if ord(self.data[self.position]) > UNSUPPORTED_ATTRIBUTES_TAG :
	212	self.position -= 1
	213	continue
	214	tag = ord(self.data[self.position])
	215	except IndexError :
	216	raise IPPError, "Unexpected end of IPP message."
	217
[631]	218	# Now transform all one-element lists into single values
	219	for attrtype in ("operation", "job", "printer") :
	220	attrdict = getattr(self, "%s_attributes" % attrtype)
	221	for (key, value) in attrdict.items() :
	222	if len(value) == 1 :
	223	attrdict[key] = value[0]
	224
[570]	225	class FakeConfig :
	226	"""Fakes a configuration file parser."""
	227	def get(self, section, option, raw=0) :
[626]	228	"""Fakes the retrieval of an option."""
[570]	229	raise ConfigError, "Invalid configuration file : no option %s in section [%s]" % (option, section)
	230
[568]	231	class CupsBackend :
	232	"""Base class for tools with no database access."""
	233	def __init__(self) :
	234	"""Initializes the CUPS backend wrapper."""
[588]	235	signal.signal(signal.SIGTERM, signal.SIG_IGN)
	236	signal.signal(signal.SIGPIPE, signal.SIG_IGN)
[577]	237	self.MyName = "Tea4CUPS"
	238	self.myname = "tea4cups"
	239	self.pid = os.getpid()
[626]	240
	241	def readConfig(self) :
	242	"""Reads the configuration file."""
[570]	243	confdir = os.environ.get("CUPS_SERVERROOT", ".")
[577]	244	self.conffile = os.path.join(confdir, "%s.conf" % self.myname)
[570]	245	if os.path.isfile(self.conffile) :
	246	self.config = ConfigParser.ConfigParser()
	247	self.config.read([self.conffile])
[573]	248	self.debug = self.isTrue(self.getGlobalOption("debug", ignore=1))
[570]	249	else :
	250	self.config = FakeConfig()
	251	self.debug = 1 # no config, so force debug mode !
	252
[574]	253	def logInfo(self, message, level="info") :
	254	"""Logs a message to CUPS' error_log file."""
[589]	255	sys.stderr.write("%s: %s v%s (PID %i) : %s\n" % (level.upper(), self.MyName, version, os.getpid(), message))
[574]	256	sys.stderr.flush()
	257
[585]	258	def logDebug(self, message) :
	259	"""Logs something to debug output if debug is enabled."""
	260	if self.debug :
	261	self.logInfo(message, level="debug")
	262
[570]	263	def isTrue(self, option) :
	264	"""Returns 1 if option is set to true, else 0."""
	265	if (option is not None) and (option.upper().strip() in ['Y', 'YES', '1', 'ON', 'T', 'TRUE']) :
	266	return 1
	267	else :
	268	return 0
	269
	270	def getGlobalOption(self, option, ignore=0) :
	271	"""Returns an option from the global section, or raises a ConfigError if ignore is not set, else returns None."""
	272	try :
	273	return self.config.get("global", option, raw=1)
	274	except (ConfigParser.NoSectionError, ConfigParser.NoOptionError) :
[577]	275	if not ignore :
[570]	276	raise ConfigError, "Option %s not found in section global of %s" % (option, self.conffile)
	277
[577]	278	def getPrintQueueOption(self, printqueuename, option, ignore=0) :
[570]	279	"""Returns an option from the printer section, or the global section, or raises a ConfigError."""
	280	globaloption = self.getGlobalOption(option, ignore=1)
	281	try :
[574]	282	return self.config.get(printqueuename, option, raw=1)
[570]	283	except (ConfigParser.NoSectionError, ConfigParser.NoOptionError) :
	284	if globaloption is not None :
	285	return globaloption
[577]	286	elif not ignore :
[574]	287	raise ConfigError, "Option %s not found in section [%s] of %s" % (option, printqueuename, self.conffile)
[571]	288
[597]	289	def enumBranches(self, printqueuename, branchtype="tee") :
	290	"""Returns the list of branchtypes branches for a particular section's."""
	291	branchbasename = "%s_" % branchtype.lower()
[573]	292	try :
[627]	293	# globalbranches = [ (k, v) for (k, v) in self.config.items("global") if k.startswith(branchbasename) ]
	294	globalbranches = [ (k, self.config.get("global", k)) for k in self.config.options("global") if k.startswith(branchbasename) ]
[573]	295	except ConfigParser.NoSectionError, msg :
[579]	296	raise ConfigError, "Invalid configuration file : %s" % msg
[573]	297	try :
[627]	298	# sectionbranches = [ (k, v) for (k, v) in self.config.items(printqueuename) if k.startswith(branchbasename) ]
	299	sectionbranches = [ (k, self.config.get(printqueuename, k)) for k in self.config.options(printqueuename) if k.startswith(branchbasename) ]
[573]	300	except ConfigParser.NoSectionError, msg :
[583]	301	self.logInfo("No section for print queue %s : %s" % (printqueuename, msg))
[573]	302	sectionbranches = []
	303	branches = {}
	304	for (k, v) in globalbranches :
	305	value = v.strip()
	306	if value :
	307	branches[k] = value
	308	for (k, v) in sectionbranches :
	309	value = v.strip()
	310	if value :
	311	branches[k] = value # overwrite any global option or set a new value
	312	else :
	313	del branches[k] # empty value disables a global option
	314	return branches
[568]	315
	316	def discoverOtherBackends(self) :
	317	"""Discovers the other CUPS backends.
	318
	319	Executes each existing backend in turn in device enumeration mode.
	320	Returns the list of available backends.
	321	"""
[569]	322	# Unfortunately this method can't output any debug information
	323	# to stdout or stderr, else CUPS considers that the device is
	324	# not available.
[568]	325	available = []
[569]	326	(directory, myname) = os.path.split(sys.argv[0])
[588]	327	if not directory :
	328	directory = "./"
[568]	329	tmpdir = tempfile.gettempdir()
[569]	330	lockfilename = os.path.join(tmpdir, "%s..LCK" % myname)
[568]	331	if os.path.exists(lockfilename) :
	332	lockfile = open(lockfilename, "r")
	333	pid = int(lockfile.read())
	334	lockfile.close()
	335	try :
	336	# see if the pid contained in the lock file is still running
	337	os.kill(pid, 0)
	338	except OSError, e :
	339	if e.errno != errno.EPERM :
	340	# process doesn't exist anymore
	341	os.remove(lockfilename)
	342
	343	if not os.path.exists(lockfilename) :
	344	lockfile = open(lockfilename, "w")
[577]	345	lockfile.write("%i" % self.pid)
[568]	346	lockfile.close()
[569]	347	allbackends = [ os.path.join(directory, b) \
	348	for b in os.listdir(directory)
	349	if os.access(os.path.join(directory, b), os.X_OK) \
	350	and (b != myname)]
	351	for backend in allbackends :
[568]	352	answer = os.popen(backend, "r")
	353	try :
	354	devices = [line.strip() for line in answer.readlines()]
	355	except :
	356	devices = []
	357	status = answer.close()
	358	if status is None :
	359	for d in devices :
	360	# each line is of the form :
	361	# 'xxxx xxxx "xxxx xxx" "xxxx xxx"'
	362	# so we have to decompose it carefully
	363	fdevice = cStringIO.StringIO(d)
	364	tokenizer = shlex.shlex(fdevice)
	365	tokenizer.wordchars = tokenizer.wordchars + \
	366	r".:,?!~/\_$*-+={}[]()#"
	367	arguments = []
	368	while 1 :
	369	token = tokenizer.get_token()
	370	if token :
	371	arguments.append(token)
	372	else :
	373	break
	374	fdevice.close()
	375	try :
	376	(devicetype, device, name, fullname) = arguments
	377	except ValueError :
	378	pass # ignore this 'bizarre' device
	379	else :
	380	if name.startswith('"') and name.endswith('"') :
	381	name = name[1:-1]
	382	if fullname.startswith('"') and fullname.endswith('"') :
	383	fullname = fullname[1:-1]
[577]	384	available.append('%s %s:%s "%s+%s" "%s managed %s"' \
	385	% (devicetype, self.myname, device, self.MyName, name, self.MyName, fullname))
[568]	386	os.remove(lockfilename)
[599]	387	available.append('direct %s:// "%s+Nothing" "%s managed Virtual Printer"' \
	388	% (self.myname, self.MyName, self.MyName))
[568]	389	return available
	390
[577]	391	def initBackend(self) :
	392	"""Initializes the backend's attributes."""
	393	# check that the DEVICE_URI environment variable's value is
	394	# prefixed with self.myname otherwise don't touch it.
	395	# If this is the case, we have to remove the prefix from
	396	# the environment before launching the real backend
	397	muststartwith = "%s:" % self.myname
	398	device_uri = os.environ.get("DEVICE_URI", "")
	399	if device_uri.startswith(muststartwith) :
	400	fulldevice_uri = device_uri[:]
	401	device_uri = fulldevice_uri[len(muststartwith):]
[583]	402	for i in range(2) :
	403	if device_uri.startswith("/") :
	404	device_uri = device_uri[1:]
[577]	405	try :
	406	(backend, destination) = device_uri.split(":", 1)
	407	except ValueError :
[583]	408	if not device_uri :
[600]	409	self.logDebug("Not attached to an existing print queue.")
[583]	410	backend = ""
	411	else :
	412	raise TeeError, "Invalid DEVICE_URI : %s\n" % device_uri
[577]	413
	414	self.JobId = sys.argv[1].strip()
[630]	415	self.UserName = sys.argv[2].strip() or pwd.getpwuid(os.geteuid())[0] # use CUPS' user when printing test pages from CUPS' web interface
[577]	416	self.Title = sys.argv[3].strip()
	417	self.Copies = int(sys.argv[4].strip())
	418	self.Options = sys.argv[5].strip()
	419	if len(sys.argv) == 7 :
	420	self.InputFile = sys.argv[6] # read job's datas from file
	421	else :
	422	self.InputFile = None # read job's datas from stdin
	423
	424	self.RealBackend = backend
	425	self.DeviceURI = device_uri
	426	self.PrinterName = os.environ.get("PRINTER", "")
	427	self.Directory = self.getPrintQueueOption(self.PrinterName, "directory")
[581]	428	self.DataFile = os.path.join(self.Directory, "%s-%s-%s-%s" % (self.myname, self.PrinterName, self.UserName, self.JobId))
[615]	429	(ippfilename, ippmessage) = self.parseIPPMessageFile()
	430	self.ControlFile = ippfilename
[631]	431	(chtype, self.ClientHost) = ippmessage.operation_attributes.get("job-originating-host-name", \
	432	ippmessage.job_attributes.get("job-originating-host-name", (None, None)))
	433	(jbtype, self.JobBilling) = ippmessage.job_attributes.get("job-billing", (None, None))
[577]	434
[583]	435	def getCupsConfigDirectives(self, directives=[]) :
	436	"""Retrieves some CUPS directives from its configuration file.
	437
	438	Returns a mapping with lowercased directives as keys and
	439	their setting as values.
	440	"""
	441	dirvalues = {}
	442	cupsroot = os.environ.get("CUPS_SERVERROOT", "/etc/cups")
	443	cupsdconf = os.path.join(cupsroot, "cupsd.conf")
	444	try :
	445	conffile = open(cupsdconf, "r")
	446	except IOError :
	447	raise TeeError, "Unable to open %s" % cupsdconf
	448	else :
	449	for line in conffile.readlines() :
	450	linecopy = line.strip().lower()
	451	for di in [d.lower() for d in directives] :
	452	if linecopy.startswith("%s " % di) :
	453	try :
	454	val = line.split()[1]
	455	except :
	456	pass # ignore errors, we take the last value in any case.
	457	else :
	458	dirvalues[di] = val
	459	conffile.close()
	460	return dirvalues
	461
[615]	462	def parseIPPMessageFile(self) :
[624]	463	"""Parses the IPP message file and returns a tuple (filename, parsedvalue)."""
[583]	464	cupsdconf = self.getCupsConfigDirectives(["RequestRoot"])
[582]	465	requestroot = cupsdconf.get("requestroot", "/var/spool/cups")
	466	if (len(self.JobId) < 5) and self.JobId.isdigit() :
	467	ippmessagefile = "c%05i" % int(self.JobId)
	468	else :
	469	ippmessagefile = "c%s" % self.JobId
	470	ippmessagefile = os.path.join(requestroot, ippmessagefile)
	471	ippmessage = {}
	472	try :
	473	ippdatafile = open(ippmessagefile)
	474	except :
	475	self.logInfo("Unable to open IPP message file %s" % ippmessagefile, "warn")
	476	else :
	477	self.logDebug("Parsing of IPP message file %s begins." % ippmessagefile)
	478	try :
	479	ippmessage = IPPMessage(ippdatafile.read())
	480	except IPPError, msg :
	481	self.logInfo("Error while parsing %s : %s" % (ippmessagefile, msg), "warn")
	482	else :
	483	self.logDebug("Parsing of IPP message file %s ends." % ippmessagefile)
	484	ippdatafile.close()
[615]	485	return (ippmessagefile, ippmessage)
[582]	486
[577]	487	def exportAttributes(self) :
	488	"""Exports our backend's attributes to the environment."""
	489	os.environ["DEVICE_URI"] = self.DeviceURI # WARNING !
	490	os.environ["TEAPRINTERNAME"] = self.PrinterName
	491	os.environ["TEADIRECTORY"] = self.Directory
	492	os.environ["TEADATAFILE"] = self.DataFile
[579]	493	os.environ["TEAJOBSIZE"] = str(self.JobSize)
[577]	494	os.environ["TEAMD5SUM"] = self.JobMD5Sum
[582]	495	os.environ["TEACLIENTHOST"] = self.ClientHost or ""
[577]	496	os.environ["TEAJOBID"] = self.JobId
	497	os.environ["TEAUSERNAME"] = self.UserName
	498	os.environ["TEATITLE"] = self.Title
	499	os.environ["TEACOPIES"] = str(self.Copies)
	500	os.environ["TEAOPTIONS"] = self.Options
	501	os.environ["TEAINPUTFILE"] = self.InputFile or ""
[615]	502	os.environ["TEABILLING"] = self.JobBilling or ""
	503	os.environ["TEACONTROLFILE"] = self.ControlFile
[577]	504
	505	def saveDatasAndCheckSum(self) :
	506	"""Saves the input datas into a static file."""
[583]	507	self.logDebug("Duplicating data stream into %s" % self.DataFile)
[577]	508	mustclose = 0
	509	if self.InputFile is not None :
	510	infile = open(self.InputFile, "rb")
	511	mustclose = 1
	512	else :
	513	infile = sys.stdin
	514	CHUNK = 64*1024 # read 64 Kb at a time
	515	dummy = 0
	516	sizeread = 0
	517	checksum = md5.new()
	518	outfile = open(self.DataFile, "wb")
	519	while 1 :
	520	data = infile.read(CHUNK)
	521	if not data :
	522	break
	523	sizeread += len(data)
	524	outfile.write(data)
	525	checksum.update(data)
	526	if not (dummy % 32) : # Only display every 2 Mb
	527	self.logDebug("%s bytes saved..." % sizeread)
	528	dummy += 1
	529	outfile.close()
	530	if mustclose :
[579]	531	infile.close()
[577]	532	self.JobSize = sizeread
	533	self.JobMD5Sum = checksum.hexdigest()
	534	self.logDebug("Job %s is %s bytes long." % (self.JobId, self.JobSize))
	535	self.logDebug("Job %s MD5 sum is %s" % (self.JobId, self.JobMD5Sum))
[568]	536
[577]	537	def cleanUp(self) :
	538	"""Cleans up the place."""
	539	if not self.isTrue(self.getPrintQueueOption(self.PrinterName, "keepfiles", ignore=1)) :
	540	os.remove(self.DataFile)
[579]	541
[588]	542	def sigtermHandler(self, signum, frame) :
	543	"""Sets an attribute whenever SIGTERM is received."""
	544	self.gotSigTerm = 1
	545	self.logInfo("SIGTERM received for Job %s." % self.JobId)
	546
[579]	547	def runBranches(self) :
[598]	548	"""Launches each hook or tee defined for the current print queue."""
[584]	549	exitcode = 0
[604]	550	self.isCancelled = 0 # did a prehook cancel the print job ?
	551	self.gotSigTerm = 0
[588]	552	signal.signal(signal.SIGTERM, self.sigtermHandler)
[598]	553	serialize = self.isTrue(self.getPrintQueueOption(self.PrinterName, "serialize", ignore=1))
	554	for branchtype in ["prehook", "tee", "posthook"] :
	555	branches = self.enumBranches(self.PrinterName, branchtype)
	556	status = self.runCommands(branchtype, branches, serialize)
	557	if status :
[625]	558	if branchtype != "posthook" :
	559	exitcode = status
	560	else :
	561	# we just ignore error in posthooks
	562	self.logInfo("An error occured during the execution of posthooks.", "warn")
[602]	563	if (branchtype == "prehook") and self.isCancelled :
[601]	564	break # We don't want to execute tees or posthooks in this case
[598]	565	signal.signal(signal.SIGTERM, signal.SIG_IGN)
[600]	566	if not exitcode :
	567	self.logInfo("OK")
	568	else :
	569	self.logInfo("An error occured, please check CUPS' error_log file.")
[598]	570	return exitcode
	571
	572	def runCommands(self, btype, branches, serialize) :
	573	"""Runs the commands for a particular branch type."""
	574	exitcode = 0
	575	btype = btype.lower()
	576	btypetitle = btype.title()
	577	branchlist = branches.keys()
	578	branchlist.sort()
	579	if serialize :
[600]	580	self.logDebug("Begin serialized %ss" % btypetitle)
[598]	581	if (btype == "tee") and self.RealBackend :
[587]	582	self.logDebug("Launching original backend %s for printer %s" % (self.RealBackend, self.PrinterName))
[608]	583	retcode = self.runOriginalBackend()
	584	if os.WIFEXITED(retcode) :
	585	retcode = os.WEXITSTATUS(retcode)
	586	os.environ["TEASTATUS"] = str(retcode)
	587	exitcode = retcode
[598]	588	for branch in branchlist :
	589	command = branches[branch]
[588]	590	if self.gotSigTerm :
	591	break
[581]	592	self.logDebug("Launching %s : %s" % (branch, command))
[584]	593	retcode = os.system(command)
[598]	594	self.logDebug("Exit code for %s %s on printer %s is %s" % (btype, branch, self.PrinterName, retcode))
[584]	595	if os.WIFEXITED(retcode) :
	596	retcode = os.WEXITSTATUS(retcode)
	597	if retcode :
[601]	598	if (btype == "prehook") and (retcode == 255) : # -1
	599	self.logInfo("Job %s cancelled by prehook %s" % (self.JobId, branch))
[602]	600	self.isCancelled = 1
[601]	601	else :
	602	self.logInfo("%s %s on printer %s didn't exit successfully." % (btypetitle, branch, self.PrinterName), "error")
	603	exitcode = 1
[600]	604	self.logDebug("End serialized %ss" % btypetitle)
[581]	605	else :
[600]	606	self.logDebug("Begin forked %ss" % btypetitle)
[584]	607	pids = {}
[598]	608	if (btype == "tee") and self.RealBackend :
[587]	609	branches["Original backend"] = None # Fakes a tee to launch one more child
[598]	610	branchlist = ["Original backend"] + branchlist
	611	for branch in branchlist :
	612	command = branches[branch]
[588]	613	if self.gotSigTerm :
	614	break
[584]	615	pid = os.fork()
	616	if pid :
	617	pids[branch] = pid
	618	else :
[587]	619	if branch == "Original backend" :
	620	self.logDebug("Launching original backend %s for printer %s" % (self.RealBackend, self.PrinterName))
	621	sys.exit(self.runOriginalBackend())
	622	else :
	623	self.logDebug("Launching %s : %s" % (branch, command))
	624	retcode = os.system(command)
	625	if os.WIFEXITED(retcode) :
	626	retcode = os.WEXITSTATUS(retcode)
	627	else :
	628	retcode = -1
	629	sys.exit(retcode)
[584]	630	for (branch, pid) in pids.items() :
	631	(childpid, retcode) = os.waitpid(pid, 0)
[598]	632	self.logDebug("Exit code for %s %s (PID %s) on printer %s is %s" % (btype, branch, childpid, self.PrinterName, retcode))
[584]	633	if os.WIFEXITED(retcode) :
	634	retcode = os.WEXITSTATUS(retcode)
	635	if retcode :
[601]	636	if (btype == "prehook") and (retcode == 255) : # -1
	637	self.logInfo("Job %s cancelled by prehook %s" % (self.JobId, branch))
[602]	638	self.isCancelled = 1
[601]	639	else :
	640	self.logInfo("%s %s (PID %s) on printer %s didn't exit successfully." % (btypetitle, branch, childpid, self.PrinterName), "error")
	641	exitcode = 1
[598]	642	if branch == "Original backend" :
	643	os.environ["TEASTATUS"] = str(retcode)
[600]	644	self.logDebug("End forked %ss" % btypetitle)
[584]	645	return exitcode
[577]	646
[588]	647	def unregisterFileNo(self, pollobj, fileno) :
	648	"""Removes a file handle from the polling object."""
	649	try :
	650	pollobj.unregister(fileno)
	651	except KeyError :
	652	self.logInfo("File number %s unregistered twice from polling object, ignored." % fileno, "warn")
	653	except :
	654	self.logDebug("Error while unregistering file number %s from polling object." % fileno)
	655	else :
	656	self.logDebug("File number %s unregistered from polling object." % fileno)
	657
	658	def formatFileEvent(self, fd, mask) :
	659	"""Formats file debug info."""
	660	maskval = []
	661	if mask & select.POLLIN :
	662	maskval.append("POLLIN")
	663	if mask & select.POLLOUT :
	664	maskval.append("POLLOUT")
	665	if mask & select.POLLPRI :
	666	maskval.append("POLLPRI")
	667	if mask & select.POLLERR :
	668	maskval.append("POLLERR")
	669	if mask & select.POLLHUP :
	670	maskval.append("POLLHUP")
	671	if mask & select.POLLNVAL :
	672	maskval.append("POLLNVAL")
	673	return "%s (%s)" % (fd, " \| ".join(maskval))
	674
[587]	675	def runOriginalBackend(self) :
	676	"""Launches the original backend."""
	677	originalbackend = os.path.join(os.path.split(sys.argv[0])[0], self.RealBackend)
	678	arguments = sys.argv
	679	self.logDebug("Starting original backend %s with args %s" % (originalbackend, " ".join(['"%s"' % a for a in ([os.environ["DEVICE_URI"]] + arguments[1:])])))
	680	subprocess = Popen4ForCUPS([originalbackend] + arguments[1:], bufsize=0, arg0=os.environ["DEVICE_URI"])
[588]	681
	682	# Save file descriptors, we will need them later.
	683	stderrfno = sys.stderr.fileno()
	684	fromcfno = subprocess.fromchild.fileno()
	685	tocfno = subprocess.tochild.fileno()
	686
	687	# We will have to be careful when dealing with I/O
	688	# So we use a poll object to know when to read or write
	689	pollster = select.poll()
	690	pollster.register(fromcfno, select.POLLIN \| select.POLLPRI)
	691	pollster.register(stderrfno, select.POLLOUT)
	692	pollster.register(tocfno, select.POLLOUT)
	693
	694	# Initialize our buffers
	695	indata = ""
	696	outdata = ""
	697	endinput = endoutput = 0
	698	inputclosed = outputclosed = 0
	699	totaltochild = totalfromcups = 0
	700	totalfromchild = totaltocups = 0
	701
[587]	702	if self.InputFile is None :
[588]	703	# this is not a real file, we read the job's data
	704	# from our temporary file which is a copy of stdin
	705	inf = open(self.DataFile, "rb")
	706	infno = inf.fileno()
	707	pollster.register(infno, select.POLLIN \| select.POLLPRI)
	708	else :
	709	# job's data is in a file, no need to pass the data
	710	# to the original backend
	711	self.logDebug("Job's data is in %s" % self.InputFile)
	712	infno = None
	713	endinput = 1
	714
	715	self.logDebug("Entering streams polling loop...")
	716	MEGABYTE = 1024*1024
	717	killed = 0
	718	status = -1
	719	while (status == -1) and (not killed) and not (inputclosed and outputclosed) :
	720	# First check if original backend is still alive
	721	status = subprocess.poll()
[587]	722
[588]	723	# Now if we got SIGTERM, we have
	724	# to kill -TERM the original backend
	725	if self.gotSigTerm and not killed :
	726	try :
	727	os.kill(subprocess.pid, signal.SIGTERM)
	728	except OSError, msg : # ignore but logs if process was already killed.
	729	self.logDebug("Error while sending signal to pid %s : %s" % (subprocess.pid, msg))
	730	else :
	731	self.logInfo(_("SIGTERM was sent to original backend %s (PID %s)") % (originalbackend, subprocess.pid))
	732	killed = 1
	733
	734	# In any case, deal with any remaining I/O
	735	try :
	736	availablefds = pollster.poll(5000)
	737	except select.error, msg :
	738	self.logDebug("Interrupted poll : %s" % msg)
	739	availablefds = []
	740	if not availablefds :
	741	self.logDebug("Nothing to do, sleeping a bit...")
	742	time.sleep(0.01) # give some time to the system
	743	else :
	744	for (fd, mask) in availablefds :
	745	try :
	746	if mask & select.POLLOUT :
	747	# We can write
	748	if fd == tocfno :
	749	if indata :
	750	try :
	751	nbwritten = os.write(fd, indata)
	752	except (OSError, IOError), msg :
	753	self.logDebug("Error while writing to original backend's stdin %s : %s" % (fd, msg))
	754	else :
	755	if len(indata) != nbwritten :
	756	self.logDebug("Short write to original backend's input !")
	757	totaltochild += nbwritten
	758	self.logDebug("%s bytes sent to original backend so far..." % totaltochild)
	759	indata = indata[nbwritten:]
	760	else :
	761	self.logDebug("No data to send to original backend yet, sleeping a bit...")
	762	time.sleep(0.01)
	763
	764	if endinput :
	765	self.unregisterFileNo(pollster, tocfno)
	766	self.logDebug("Closing original backend's stdin.")
	767	os.close(tocfno)
	768	inputclosed = 1
	769	elif fd == stderrfno :
	770	if outdata :
	771	try :
	772	nbwritten = os.write(fd, outdata)
	773	except (OSError, IOError), msg :
	774	self.logDebug("Error while writing to CUPS back channel (stderr) %s : %s" % (fd, msg))
	775	else :
	776	if len(outdata) != nbwritten :
	777	self.logDebug("Short write to stderr (CUPS) !")
	778	totaltocups += nbwritten
	779	self.logDebug("%s bytes sent back to CUPS so far..." % totaltocups)
	780	outdata = outdata[nbwritten:]
	781	else :
	782	# self.logDebug("No data to send back to CUPS yet, sleeping a bit...") # Uncommenting this fills your logs
	783	time.sleep(0.01) # Give some time to the system, stderr is ALWAYS writeable it seems.
	784
	785	if endoutput :
	786	self.unregisterFileNo(pollster, stderrfno)
	787	outputclosed = 1
	788	else :
	789	self.logDebug("Unexpected : %s - Sleeping a bit..." % self.formatFileEvent(fd, mask))
	790	time.sleep(0.01)
	791
	792	if mask & (select.POLLIN \| select.POLLPRI) :
	793	# We have something to read
	794	try :
	795	data = os.read(fd, MEGABYTE)
	796	except (IOError, OSError), msg :
	797	self.logDebug("Error while reading file %s : %s" % (fd, msg))
	798	else :
	799	if fd == infno :
	800	if not data : # If yes, then no more input data
	801	self.unregisterFileNo(pollster, infno)
	802	self.logDebug("Input data ends.")
	803	endinput = 1 # this happens with real files.
	804	else :
	805	indata += data
	806	totalfromcups += len(data)
	807	self.logDebug("%s bytes read from CUPS so far..." % totalfromcups)
	808	elif fd == fromcfno :
	809	if not data :
	810	self.logDebug("No back channel data to read from original backend yet, sleeping a bit...")
	811	time.sleep(0.01)
	812	else :
	813	outdata += data
	814	totalfromchild += len(data)
	815	self.logDebug("%s bytes read from original backend so far..." % totalfromchild)
	816	else :
	817	self.logDebug("Unexpected : %s - Sleeping a bit..." % self.formatFileEvent(fd, mask))
	818	time.sleep(0.01)
	819
	820	if mask & (select.POLLHUP \| select.POLLERR) :
	821	# Treat POLLERR as an EOF.
	822	# Some standard I/O stream has no more datas
	823	self.unregisterFileNo(pollster, fd)
	824	if fd == infno :
	825	# Here we are in the case where the input file is stdin.
	826	# which has no more data to be read.
	827	self.logDebug("Input data ends.")
	828	endinput = 1
	829	elif fd == fromcfno :
	830	# We are no more interested in this file descriptor
	831	self.logDebug("Closing original backend's stdout+stderr.")
	832	os.close(fromcfno)
	833	endoutput = 1
	834	else :
	835	self.logDebug("Unexpected : %s - Sleeping a bit..." % self.formatFileEvent(fd, mask))
	836	time.sleep(0.01)
	837
	838	if mask & select.POLLNVAL :
	839	self.logDebug("File %s was closed. Unregistering from polling object." % fd)
	840	self.unregisterFileNo(pollster, fd)
	841	except IOError, msg :
	842	self.logDebug("Got an IOError : %s" % msg) # we got signalled during an I/O
	843
	844	# We must close the original backend's input stream
	845	if killed and not inputclosed :
	846	self.logDebug("Forcing close of original backend's stdin.")
	847	os.close(tocfno)
	848
	849	self.logDebug("Exiting streams polling loop...")
	850
	851	self.logDebug("input data's final length : %s" % len(indata))
	852	self.logDebug("back-channel data's final length : %s" % len(outdata))
	853
	854	self.logDebug("Total bytes read from CUPS (job's datas) : %s" % totalfromcups)
	855	self.logDebug("Total bytes sent to original backend (job's datas) : %s" % totaltochild)
	856
	857	self.logDebug("Total bytes read from original backend (back-channel datas) : %s" % totalfromchild)
	858	self.logDebug("Total bytes sent back to CUPS (back-channel datas) : %s" % totaltocups)
	859
	860	# Check exit code of original CUPS backend.
	861	if status == -1 :
	862	# we exited the loop before the original backend exited
	863	# now we have to wait for it to finish and get its status
	864	self.logDebug("Waiting for original backend to exit...")
	865	try :
	866	status = subprocess.wait()
	867	except OSError : # already dead : TODO : detect when abnormal
	868	status = 0
[587]	869	if os.WIFEXITED(status) :
	870	return os.WEXITSTATUS(status)
[588]	871	elif not killed :
	872	self.logInfo("CUPS backend %s died abnormally." % originalbackend, "error")
	873	return -1
[587]	874	else :
	875	return 1
	876
[565]	877	if __name__ == "__main__" :
	878	# This is a CUPS backend, we should act and die like a CUPS backend
[568]	879	wrapper = CupsBackend()
[565]	880	if len(sys.argv) == 1 :
[568]	881	print "\n".join(wrapper.discoverOtherBackends())
	882	sys.exit(0)
[565]	883	elif len(sys.argv) not in (6, 7) :
[568]	884	sys.stderr.write("ERROR: %s job-id user title copies options [file]\n"\
	885	% sys.argv[0])
	886	sys.exit(1)
[565]	887	else :
[585]	888	try :
[626]	889	wrapper.readConfig()
[585]	890	wrapper.initBackend()
	891	wrapper.saveDatasAndCheckSum()
	892	wrapper.exportAttributes()
	893	retcode = wrapper.runBranches()
	894	wrapper.cleanUp()
	895	except SystemExit, e :
	896	retcode = e.code
	897	except :
	898	import traceback
	899	lines = []
	900	for line in traceback.format_exception(*sys.exc_info()) :
	901	lines.extend([l for l in line.split("\n") if l])
	902	msg = "ERROR: ".join(["%s (PID %s) : %s\n" % (wrapper.MyName, wrapper.pid, l) for l in (["ERROR: Tea4CUPS v%s" % version] + lines)])
	903	sys.stderr.write(msg)
	904	sys.stderr.flush()
	905	retcode = 1
[579]	906	sys.exit(retcode)

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