| ######################## BEGIN LICENSE BLOCK ######################## |
| # The Original Code is mozilla.org code. |
| # |
| # The Initial Developer of the Original Code is |
| # Netscape Communications Corporation. |
| # Portions created by the Initial Developer are Copyright (C) 1998 |
| # the Initial Developer. All Rights Reserved. |
| # |
| # Contributor(s): |
| # Mark Pilgrim - port to Python |
| # |
| # This library is free software; you can redistribute it and/or |
| # modify it under the terms of the GNU Lesser General Public |
| # License as published by the Free Software Foundation; either |
| # version 2.1 of the License, or (at your option) any later version. |
| # |
| # This library is distributed in the hope that it will be useful, |
| # but WITHOUT ANY WARRANTY; without even the implied warranty of |
| # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| # Lesser General Public License for more details. |
| # |
| # You should have received a copy of the GNU Lesser General Public |
| # License along with this library; if not, write to the Free Software |
| # Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA |
| # 02110-1301 USA |
| ######################### END LICENSE BLOCK ######################### |
| |
| from . import constants |
| from .charsetprober import CharSetProber |
| from .codingstatemachine import CodingStateMachine |
| from .mbcssm import UTF8SMModel |
| |
| ONE_CHAR_PROB = 0.5 |
| |
| |
| class UTF8Prober(CharSetProber): |
| def __init__(self): |
| CharSetProber.__init__(self) |
| self._mCodingSM = CodingStateMachine(UTF8SMModel) |
| self.reset() |
| |
| def reset(self): |
| CharSetProber.reset(self) |
| self._mCodingSM.reset() |
| self._mNumOfMBChar = 0 |
| |
| def get_charset_name(self): |
| return "utf-8" |
| |
| def feed(self, aBuf): |
| for c in aBuf: |
| codingState = self._mCodingSM.next_state(c) |
| if codingState == constants.eError: |
| self._mState = constants.eNotMe |
| break |
| elif codingState == constants.eItsMe: |
| self._mState = constants.eFoundIt |
| break |
| elif codingState == constants.eStart: |
| if self._mCodingSM.get_current_charlen() >= 2: |
| self._mNumOfMBChar += 1 |
| |
| if self.get_state() == constants.eDetecting: |
| if self.get_confidence() > constants.SHORTCUT_THRESHOLD: |
| self._mState = constants.eFoundIt |
| |
| return self.get_state() |
| |
| def get_confidence(self): |
| unlike = 0.99 |
| if self._mNumOfMBChar < 6: |
| for i in range(0, self._mNumOfMBChar): |
| unlike = unlike * ONE_CHAR_PROB |
| return 1.0 - unlike |
| else: |
| return unlike |
