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source: server/lib/ippvalue.py @ 5cfb358

no-cups

Last change on this file since 5cfb358 was 5cfb358, checked in by Jessica B. Hamrick <jhamrick@…>, 13 years ago
Change structure of ippvalue.Value to make it easier to manipulate.
Property mode set to `100644`
File size: 15.2 KB

Rev	Line
[8979f90]	1	#!/usr/bin/python
	2
	3	import sys, struct, logging
[2646571]	4	from ippconstants import *
[8979f90]	5
	6	# initialize logger
	7	logger = logging.getLogger("ippLogger")
	8
[ebf327d]	9	class Value():
[8979f90]	10	"""
[5cfb358]	11	An IPP value consists of a tag and a value.
[8979f90]	12
	13	From RFC 2565:
	14	-----------------------------------------------
	15	\| value-tag \| 1 byte
	16	-----------------------------------------------
[5cfb358]	17	\| name-length (value is 0x0000) \| 2 bytes
[8979f90]	18	-----------------------------------------------
	19	\| value-length (value is v) \| 2 bytes
	20	-----------------------------------------------
	21	\| value \| v bytes
	22	-----------------------------------------------
	23	"""
	24
[5cfb358]	25	def __init__(self, value_tag=None, value=None, unpack=True):
[8979f90]	26	"""
[5cfb358]	27	Initialize a Value. There are three different ways you can
	28	call this method:
	29
	30	Value() -- creates an empty Value instance
	31
	32	Value(value_tag, value) -- creates a Value instance from
	33	binary values
	34
	35	Value(value_tag, value, unpack=False) -- creates a Value
	36	instance from non-binary values
	37
	38	If you create an empty Value instance, once you have set
	39	value_tag and value, you should call pack(), or if you set
	40	value_tag and binary_value, call unpack().
[8979f90]	41
	42	Arguments:
	43
	44	value_tag -- one byte, identifying the type of value
	45
[5cfb358]	46	value -- variable size, containing the actual value. If
	47	unpack is True, then this should be a binary value,
	48	otherwise it should be a string or number.
	49
	50	unpack -- boolean which indicates whether the value passed
	51	in is binary (i.e., should be unpacked) or not (i.e., does
	52	not need to be unpacked)
[8979f90]	53	"""
	54
[5cfb358]	55	# make sure the arguments are valid
	56	if value_tag is not None:
	57	assert value is not None, \
	58	"value must not be null because " + \
	59	"value_tag is not null!"
	60	elif value_tag is None:
	61	assert value is None, \
	62	"value must be null because value_tag is null!"
[8979f90]	63
[5cfb358]	64	# initialize member variables
	65	self.value_tag = None # one byte, the type of value
	66	self.value = None # non-binary value of self.value
	67	self.value_size = None # size of self.value
	68	self.binary_value = None # binary value of self.value
	69
	70	if value_tag is not None and value is not None:
	71	if unpack:
	72	self.value_tag = value_tag
	73	self.binary_value = value
	74	self.unpack()
	75	self.pack()
	76	else:
	77	self.value_tag = value_tag
	78	self.value = value
	79	self.pack()
	80	self.unpack()
	81
	82	def unpack(self):
	83	"""
	84	Given self.value_tag and self.binary_value, unpack the binary
	85	value into either a string or number. These values MUST NOT
	86	be null. Furthermore, if self.value and self.value_size are
	87	set, this method will check to make sure that unpacking
	88	self.binary_value matches up.
	89
	90	Returns: tuple of (value_size, value)
	91	"""
[8979f90]	92
[5cfb358]	93	assert self.value_tag is not None, \
	94	"Cannot unpack values with unspecified value tag!"
	95	assert self.binary_value is not None, \
	96	"Cannot unpack null values!"
	97
	98	value_size = None
	99	value = None
[8979f90]	100
	101	# out-of-band value tags
[2646571]	102	if self.value_tag == OutOfBandTags.UNSUPPORTED or \
	103	self.value_tag == OutOfBandTags.DEFAULT or \
	104	self.value_tag == OutOfBandTags.UNKNOWN or \
	105	self.value_tag == OutOfBandTags.NO_VALUE:
[5cfb358]	106	value_size = 0
	107	value = ''
[8979f90]	108
	109	# integer value tags
[2646571]	110	elif self.value_tag == IntegerTags.INTEGER:
[5cfb358]	111	value_size = 4
	112	value = struct.unpack('>i', self.binary_value)[0]
[2646571]	113	elif self.value_tag == IntegerTags.BOOLEAN:
[5cfb358]	114	value_size = 1
	115	value = struct.unpack('>?', self.binary_value)[0]
[2646571]	116	elif self.value_tag == IntegerTags.ENUM:
[5cfb358]	117	value_size = 4
	118	value = struct.unpack('>i', self.binary_value)[0]
[8979f90]	119
	120
[2646571]	121	elif self.value_tag == OctetStringTags.DATETIME:
[8979f90]	122	# field octets contents range
	123	# ----- ------ -------- -----
	124	# 1 1-2 year 0..65536
	125	# 2 3 month 1..12
	126	# 3 4 day 1..31
	127	# 4 5 hour 0..23
	128	# 5 6 minutes 0..59
	129	# 6 7 seconds 0..60
	130	# (use 60 for leap-second)
	131	# 7 8 deci-seconds 0..9
	132	# 8 9 direction from UTC '+' / '-'
	133	# 9 10 hours from UTC 0..11
	134	# 10 11 minutes from UTC 0..59
	135
[5cfb358]	136	value_size = 11
	137	value = struct.unpack('>hbbbbbbcbb', self.binary_value)[0]
[8979f90]	138
[2646571]	139	elif self.value_tag == OctetStringTags.RESOLUTION:
[8979f90]	140	# OCTET-STRING consisting of nine octets of 2
	141	# SIGNED-INTEGERs followed by a SIGNED-BYTE. The first
	142	# SIGNED-INTEGER contains the value of cross feed
	143	# direction resolution. The second SIGNED-INTEGER contains
	144	# the value of feed direction resolution. The SIGNED-BYTE
	145	# contains the units
	146
[5cfb358]	147	value_size = 9
	148	value = struct.unpack('>iib', self.binary_value)
[8979f90]	149
[2646571]	150	elif self.value_tag == OctetStringTags.RANGE_OF_INTEGER:
[8979f90]	151	# Eight octets consisting of 2 SIGNED-INTEGERs. The first
	152	# SIGNED-INTEGER contains the lower bound and the second
	153	# SIGNED-INTEGER contains the upper bound.
	154
[5cfb358]	155	value_size = 8
	156	value = struct.unpack('>ii', self.binary_value)
[8979f90]	157
[2646571]	158	elif self.value_tag == OctetStringTags.TEXT_WITH_LANGUAGE or \
	159	self.value_tag == OctetStringTags.NAME_WITH_LANGUAGE:
[5cfb358]	160	a = struct.unpack('>h', self.binary_value[:2])[0]
	161	b = struct.unpack('>%ss' % a, self.binary_value[2:a+2])[0]
	162	c = struct.unpack('>h', self.binary_value[a+2:a+4])[0]
	163	d = struct.unpack('>%ss' % c, self.binary_value[a+4:][0])
	164	value_size = 4 + a + c
	165	value = (a, b, c, d)
[8979f90]	166
	167	# character string value tags
[5cfb358]	168	elif self.value_tag == \
	169	CharacterStringTags.TEXT_WITHOUT_LANGUAGE or \
	170	self.value_tag == \
	171	CharacterStringTags.NAME_WITHOUT_LANGUAGE:
	172	value_size = len(str(self.binary_value))
	173	value = str(self.binary_value)
[2646571]	174	elif self.value_tag == CharacterStringTags.GENERIC or \
	175	self.value_tag == CharacterStringTags.KEYWORD or \
	176	self.value_tag == CharacterStringTags.URI or \
	177	self.value_tag == CharacterStringTags.URI_SCHEME or \
	178	self.value_tag == CharacterStringTags.CHARSET or \
	179	self.value_tag == CharacterStringTags.NATURAL_LANGUAGE or \
	180	self.value_tag == CharacterStringTags.MIME_MEDIA_TYPE:
[5cfb358]	181	value_size = len(str(self.binary_value))
	182	value = str(self.binary_value)
[8979f90]	183
[5cfb358]	184	# anything else that we didn't handle
	185	else:
	186	if value_size is None and value is None:
	187	value_size = len(self.binary_value)
	188	value = self.binary_value
	189
	190	if self.value_size is not None:
	191	assert value_size == self.value_size, \
	192	"unpacked value_size is not the same " + \
	193	"as self.value_size!"
	194	if self.value is not None:
	195	assert value == self.value, \
	196	"unpacked value is not the same as self.value!"
	197
	198	self.value_size = value_size
	199	self.value = value
	200
	201	return value_size, value
	202
	203	def pack(self):
	204	"""
	205	Given self.value_tag and self.value, pack the value into
	206	binary formo. These values MUST NOT be null. Furthermore, if
	207	self.binary_value and self.value_size are set, this method
	208	will check to make sure that packing self.value matches up.
	209
	210	Returns: tuple of (value_size, binary_value)
	211	"""
	212
	213	assert self.value_tag is not None, \
	214	"cannot pack value with null value tag!"
	215	assert self.value is not None, \
	216	"cannot pack null value!"
	217
	218	value_size = None
	219	binary_value = None
[8979f90]	220
	221	# out-of-band value tags
[2646571]	222	if self.value_tag == OutOfBandTags.UNSUPPORTED or \
	223	self.value_tag == OutOfBandTags.DEFAULT or \
	224	self.value_tag == OutOfBandTags.UNKNOWN or \
	225	self.value_tag == OutOfBandTags.NO_VALUE:
[5cfb358]	226	value_size = 0
	227	binary_value = ''
[8979f90]	228
	229	# integer value tags
[2646571]	230	elif self.value_tag == IntegerTags.INTEGER:
[5cfb358]	231	value_size = 4
	232	binary_value = struct.pack('>i', self.value)
[2646571]	233	elif self.value_tag == IntegerTags.BOOLEAN:
[5cfb358]	234	value_size = 1
	235	binary_value = struct.pack('>?', self.value)
[2646571]	236	elif self.value_tag == IntegerTags.ENUM:
[5cfb358]	237	value_size = 4
	238	binary_value = struct.pack('>i', self.value)
[8979f90]	239
	240	# octet string value tags
[2646571]	241	elif self.value_tag == OctetStringTags.DATETIME:
[8979f90]	242	# field octets contents range
	243	# ----- ------ -------- -----
	244	# 1 1-2 year 0..65536
	245	# 2 3 month 1..12
	246	# 3 4 day 1..31
	247	# 4 5 hour 0..23
	248	# 5 6 minutes 0..59
	249	# 6 7 seconds 0..60
	250	# (use 60 for leap-second)
	251	# 7 8 deci-seconds 0..9
	252	# 8 9 direction from UTC '+' / '-'
	253	# 9 10 hours from UTC 0..11
	254	# 10 11 minutes from UTC 0..59
[5cfb358]	255
	256	value_size = 11
	257	binary_value = struct.pack('>hbbbbbbcbb', self.value)
[8979f90]	258
[2646571]	259	elif self.value_tag == OctetStringTags.RESOLUTION:
[8979f90]	260	# OCTET-STRING consisting of nine octets of 2
	261	# SIGNED-INTEGERs followed by a SIGNED-BYTE. The first
	262	# SIGNED-INTEGER contains the value of cross feed
	263	# direction resolution. The second SIGNED-INTEGER contains
	264	# the value of feed direction resolution. The SIGNED-BYTE
	265	# contains the units
[5cfb358]	266
	267	value_size = 9
	268	binary_value = truct.pack('>iib', self.value)
[8979f90]	269
[2646571]	270	elif self.value_tag == OctetStringTags.RANGE_OF_INTEGER:
[8979f90]	271	# Eight octets consisting of 2 SIGNED-INTEGERs. The first
	272	# SIGNED-INTEGER contains the lower bound and the second
	273	# SIGNED-INTEGER contains the upper bound.
[5cfb358]	274
	275	value_size = 8
	276	binary_value = struct.pack('>ii', self.value)
[8979f90]	277
[2646571]	278	elif self.value_tag == OctetStringTags.TEXT_WITH_LANGUAGE or \
	279	self.value_tag == OctetStringTags.NAME_WITH_LANGUAGE:
[5cfb358]	280
[8979f90]	281	a_bin = struct.pack('>h', self.value[0])
	282	b_bin = struct.pack('>%ss' % self.value[0], self.value[1])
	283	c_bin = struct.pack('>h', self.value[2])
	284	d_bin = struct.pack('>%ss' % self.value[2], self.value[3])
[5cfb358]	285
	286	value_size = 4 + self.value[0] + self.value[2]
	287	binary_value = a_bin + b_bin + c_bin + d_bin
[8979f90]	288
	289	# character string value tags
[5cfb358]	290	elif self.value_tag == \
	291	CharacterStringTags.TEXT_WITHOUT_LANGUAGE or \
	292	self.value_tag == \
	293	CharacterStringTags.NAME_WITHOUT_LANGUAGE:
	294
	295	value_size = len(self.value)
	296	binary_value = struct.pack('>%ss' % len(self.value),
	297	self.value)
	298
[2646571]	299	elif self.value_tag == CharacterStringTags.GENERIC or \
	300	self.value_tag == CharacterStringTags.KEYWORD or \
	301	self.value_tag == CharacterStringTags.URI or \
	302	self.value_tag == CharacterStringTags.URI_SCHEME or \
	303	self.value_tag == CharacterStringTags.CHARSET or \
	304	self.value_tag == CharacterStringTags.NATURAL_LANGUAGE or \
	305	self.value_tag == CharacterStringTags.MIME_MEDIA_TYPE:
[5cfb358]	306
	307	value_size = len(self.value)
	308	binary_value = struct.pack('>%ss' % len(self.value),
	309	self.value)
	310
	311	else:
	312	value_size = len(self.value)
	313	binary_value = self.value
	314
	315	if self.value_size is not None:
	316	assert value_size == self.value_size, \
	317	"packed value size is not the same as " + \
	318	"self.value_size!"
	319	if self.binary_value is not None:
	320	assert binary_value == self.binary_value, \
	321	"packed binary value is not the same as " + \
	322	"self.binary_value!"
	323
	324	self.value_size = value_size
	325	self.binary_value = binary_value
	326
	327	return value_size, binary_value
	328
	329	def verify(self):
	330	"""
	331	Verifies that the binary and non-binary values for this Value
	332	instance line up. All of self.value, self.binary_value,
	333	self.value_size, and self.value_tag must be defined.
	334
	335	This function will throw an assertion error if the Value
	336	instance is not valid.
	337	"""
	338
	339	assert self.value is not None, \
	340	"value is null!"
	341	assert self.binary_value is not None, \
	342	"binary value is null!"
	343	assert self.value_size is not None, \
	344	"value size is unknown!"
	345	assert self.value_tag is not None, \
	346	"value type is unknown!"
	347
	348	self.pack()
	349	self.unpack()
	350
	351	def getValue(self):
	352	"""
	353	Get the non-binary value.
	354	"""
	355
	356	return self.value
	357
	358	def getBinaryValue(self):
	359	"""
	360	Get the binary value.
	361	"""
	362
	363	return self.binary_value
	364
	365	def getValueTag(self):
	366	"""
	367	Get the value tag (type of value). This is an integer
	368	corresponding to a value in ippconstants.
	369	"""
	370
	371	return self.value_tag
	372
	373	def getSize(self):
	374	"""
	375	Get the size of the value in bytes.
	376	"""
	377
	378	return self.value_size
	379
	380	def setValue(self, value):
	381	"""
	382	Set the non-binary value.
	383	"""
	384
	385	self.value = value
	386
	387	def setBinaryValue(self, binary_value):
	388	"""
	389	Set the binary value.
	390	"""
	391	self.binary_value = binary_value
	392
	393	def setValueTag(self, value_tag):
	394	"""
	395	Set the type (tag) of the value. This should correspond to an
	396	integer defined in ippconstants.
	397	"""
	398
	399	self.value_tag = value_tag
	400
	401	def setSize(self, size):
	402	"""
	403	Set the size of the value in bytes.
	404	"""
	405
	406	self.value_size = size
[8979f90]	407
[5cfb358]	408	def __str__(self):
	409	return self.value

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