bb42f2fb5e8189d442f3db4d4461ea6b230824b3
[sdc/sdc-distribution-client.git] /
1 ######################## BEGIN LICENSE BLOCK ########################
2 # The Original Code is Mozilla Universal charset detector code.
3 #
4 # The Initial Developer of the Original Code is
5 # Netscape Communications Corporation.
6 # Portions created by the Initial Developer are Copyright (C) 2001
7 # the Initial Developer. All Rights Reserved.
8 #
9 # Contributor(s):
10 #   Mark Pilgrim - port to Python
11 #   Shy Shalom - original C code
12 #   Proofpoint, Inc.
13 #
14 # This library is free software; you can redistribute it and/or
15 # modify it under the terms of the GNU Lesser General Public
16 # License as published by the Free Software Foundation; either
17 # version 2.1 of the License, or (at your option) any later version.
18 #
19 # This library is distributed in the hope that it will be useful,
20 # but WITHOUT ANY WARRANTY; without even the implied warranty of
21 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
22 # Lesser General Public License for more details.
23 #
24 # You should have received a copy of the GNU Lesser General Public
25 # License along with this library; if not, write to the Free Software
26 # Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
27 # 02110-1301  USA
28 ######################### END LICENSE BLOCK #########################
29
30 import sys
31 from . import constants
32 from .charsetprober import CharSetProber
33
34
35 class MultiByteCharSetProber(CharSetProber):
36     def __init__(self):
37         CharSetProber.__init__(self)
38         self._mDistributionAnalyzer = None
39         self._mCodingSM = None
40         self._mLastChar = [0, 0]
41
42     def reset(self):
43         CharSetProber.reset(self)
44         if self._mCodingSM:
45             self._mCodingSM.reset()
46         if self._mDistributionAnalyzer:
47             self._mDistributionAnalyzer.reset()
48         self._mLastChar = [0, 0]
49
50     def get_charset_name(self):
51         pass
52
53     def feed(self, aBuf):
54         aLen = len(aBuf)
55         for i in range(0, aLen):
56             codingState = self._mCodingSM.next_state(aBuf[i])
57             if codingState == constants.eError:
58                 if constants._debug:
59                     sys.stderr.write(self.get_charset_name()
60                                      + ' prober hit error at byte ' + str(i)
61                                      + '\n')
62                 self._mState = constants.eNotMe
63                 break
64             elif codingState == constants.eItsMe:
65                 self._mState = constants.eFoundIt
66                 break
67             elif codingState == constants.eStart:
68                 charLen = self._mCodingSM.get_current_charlen()
69                 if i == 0:
70                     self._mLastChar[1] = aBuf[0]
71                     self._mDistributionAnalyzer.feed(self._mLastChar, charLen)
72                 else:
73                     self._mDistributionAnalyzer.feed(aBuf[i - 1:i + 1],
74                                                      charLen)
75
76         self._mLastChar[0] = aBuf[aLen - 1]
77
78         if self.get_state() == constants.eDetecting:
79             if (self._mDistributionAnalyzer.got_enough_data() and
80                     (self.get_confidence() > constants.SHORTCUT_THRESHOLD)):
81                 self._mState = constants.eFoundIt
82
83         return self.get_state()
84
85     def get_confidence(self):
86         return self._mDistributionAnalyzer.get_confidence()