| | 54 | class IPPError(TeeError) : |
| | 55 | """IPP related exceptions.""" |
| | 56 | pass |
| | 57 | |
| | 58 | class IPPMessage : |
| | 59 | """A class for IPP message files.""" |
| | 60 | def __init__(self, data) : |
| | 61 | """Initializes an IPP Message object.""" |
| | 62 | self.data = data |
| | 63 | self._attributes = {} |
| | 64 | self.curname = None |
| | 65 | self.tags = [ None ] * 256 # by default all tags reserved |
| | 66 | |
| | 67 | # Delimiter tags |
| | 68 | self.tags[0x01] = "operation-attributes-tag" |
| | 69 | self.tags[0x02] = "job-attributes-tag" |
| | 70 | self.tags[0x03] = "end-of-attributes-tag" |
| | 71 | self.tags[0x04] = "printer-attributes-tag" |
| | 72 | self.tags[0x05] = "unsupported-attributes-tag" |
| | 73 | |
| | 74 | # out of band values |
| | 75 | self.tags[0x10] = "unsupported" |
| | 76 | self.tags[0x11] = "reserved-for-future-default" |
| | 77 | self.tags[0x12] = "unknown" |
| | 78 | self.tags[0x13] = "no-value" |
| | 79 | |
| | 80 | # integer values |
| | 81 | self.tags[0x20] = "generic-integer" |
| | 82 | self.tags[0x21] = "integer" |
| | 83 | self.tags[0x22] = "boolean" |
| | 84 | self.tags[0x23] = "enum" |
| | 85 | |
| | 86 | # octetString |
| | 87 | self.tags[0x30] = "octetString-with-an-unspecified-format" |
| | 88 | self.tags[0x31] = "dateTime" |
| | 89 | self.tags[0x32] = "resolution" |
| | 90 | self.tags[0x33] = "rangeOfInteger" |
| | 91 | self.tags[0x34] = "reserved-for-collection" |
| | 92 | self.tags[0x35] = "textWithLanguage" |
| | 93 | self.tags[0x36] = "nameWithLanguage" |
| | 94 | |
| | 95 | # character strings |
| | 96 | self.tags[0x20] = "generic-character-string" |
| | 97 | self.tags[0x41] = "textWithoutLanguage" |
| | 98 | self.tags[0x42] = "nameWithoutLanguage" |
| | 99 | # self.tags[0x43] = "reserved" |
| | 100 | self.tags[0x44] = "keyword" |
| | 101 | self.tags[0x45] = "uri" |
| | 102 | self.tags[0x46] = "uriScheme" |
| | 103 | self.tags[0x47] = "charset" |
| | 104 | self.tags[0x48] = "naturalLanguage" |
| | 105 | self.tags[0x49] = "mimeMediaType" |
| | 106 | |
| | 107 | # now parses the IPP message |
| | 108 | self.parse() |
| | 109 | |
| | 110 | def __getattr__(self, attrname) : |
| | 111 | """Allows self.attributes to return the attributes names.""" |
| | 112 | if attrname == "attributes" : |
| | 113 | keys = self._attributes.keys() |
| | 114 | keys.sort() |
| | 115 | return keys |
| | 116 | raise AttributeError, attrname |
| | 117 | |
| | 118 | def __getitem__(self, ippattrname) : |
| | 119 | """Fakes a dictionnary d['key'] notation.""" |
| | 120 | value = self._attributes.get(ippattrname) |
| | 121 | if value is not None : |
| | 122 | if len(value) == 1 : |
| | 123 | value = value[0] |
| | 124 | return value |
| | 125 | get = __getitem__ |
| | 126 | |
| | 127 | def parseTag(self) : |
| | 128 | """Extracts information from an IPP tag.""" |
| | 129 | pos = self.position |
| | 130 | valuetag = self.tags[ord(self.data[pos])] |
| | 131 | # print valuetag.get("name") |
| | 132 | pos += 1 |
| | 133 | posend = pos2 = pos + 2 |
| | 134 | namelength = unpack(">H", self.data[pos:pos2])[0] |
| | 135 | if not namelength : |
| | 136 | name = self.curname |
| | 137 | else : |
| | 138 | posend += namelength |
| | 139 | self.curname = name = self.data[pos2:posend] |
| | 140 | pos2 = posend + 2 |
| | 141 | valuelength = unpack(">H", self.data[posend:pos2])[0] |
| | 142 | posend = pos2 + valuelength |
| | 143 | value = self.data[pos2:posend] |
| | 144 | oldval = self._attributes.setdefault(name, []) |
| | 145 | oldval.append(value) |
| | 146 | return posend - self.position |
| | 147 | |
| | 148 | def operation_attributes_tag(self) : |
| | 149 | """Indicates that the parser enters into an operation-attributes-tag group.""" |
| | 150 | return self.parseTag() |
| | 151 | |
| | 152 | def job_attributes_tag(self) : |
| | 153 | """Indicates that the parser enters into an operation-attributes-tag group.""" |
| | 154 | return self.parseTag() |
| | 155 | |
| | 156 | def printer_attributes_tag(self) : |
| | 157 | """Indicates that the parser enters into an operation-attributes-tag group.""" |
| | 158 | return self.parseTag() |
| | 159 | |
| | 160 | def parse(self) : |
| | 161 | """Parses an IPP Message. |
| | 162 | |
| | 163 | NB : Only a subset of RFC2910 is implemented. |
| | 164 | We are only interested in textual informations for now anyway. |
| | 165 | """ |
| | 166 | self.version = "%s.%s" % (ord(self.data[0]), ord(self.data[1])) |
| | 167 | self.operation_id = "0x%04x" % unpack(">H", self.data[2:4])[0] |
| | 168 | self.request_id = "0x%08x" % unpack(">I", self.data[4:8])[0] |
| | 169 | self.position = 8 |
| | 170 | try : |
| | 171 | tag = ord(self.data[self.position]) |
| | 172 | while tag != END_OF_ATTRIBUTES_TAG : |
| | 173 | self.position += 1 |
| | 174 | name = self.tags[tag] |
| | 175 | if name is not None : |
| | 176 | func = getattr(self, name.replace("-", "_"), None) |
| | 177 | if func is not None : |
| | 178 | self.position += func() |
| | 179 | if ord(self.data[self.position]) > UNSUPPORTED_ATTRIBUTES_TAG : |
| | 180 | self.position -= 1 |
| | 181 | continue |
| | 182 | tag = ord(self.data[self.position]) |
| | 183 | except IndexError : |
| | 184 | raise IPPError, "Unexpected end of IPP message." |
| | 185 | |
