| ######################## 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 .charsetprober import CharSetProber |
| from .codingstatemachine import CodingStateMachine |
| from .enums import LanguageFilter, MachineState, ProbingState |
| from .escsm import ( |
| HZ_SM_MODEL, |
| ISO2022CN_SM_MODEL, |
| ISO2022JP_SM_MODEL, |
| ISO2022KR_SM_MODEL, |
| ) |
| |
| |
| class EscCharSetProber(CharSetProber): |
| """ |
| This CharSetProber uses a "code scheme" approach for detecting encodings, |
| whereby easily recognizable escape or shift sequences are relied on to |
| identify these encodings. |
| """ |
| |
| def __init__(self, lang_filter=None): |
| super().__init__(lang_filter=lang_filter) |
| self.coding_sm = [] |
| if self.lang_filter & LanguageFilter.CHINESE_SIMPLIFIED: |
| self.coding_sm.append(CodingStateMachine(HZ_SM_MODEL)) |
| self.coding_sm.append(CodingStateMachine(ISO2022CN_SM_MODEL)) |
| if self.lang_filter & LanguageFilter.JAPANESE: |
| self.coding_sm.append(CodingStateMachine(ISO2022JP_SM_MODEL)) |
| if self.lang_filter & LanguageFilter.KOREAN: |
| self.coding_sm.append(CodingStateMachine(ISO2022KR_SM_MODEL)) |
| self.active_sm_count = None |
| self._detected_charset = None |
| self._detected_language = None |
| self._state = None |
| self.reset() |
| |
| def reset(self): |
| super().reset() |
| for coding_sm in self.coding_sm: |
| if not coding_sm: |
| continue |
| coding_sm.active = True |
| coding_sm.reset() |
| self.active_sm_count = len(self.coding_sm) |
| self._detected_charset = None |
| self._detected_language = None |
| |
| @property |
| def charset_name(self): |
| return self._detected_charset |
| |
| @property |
| def language(self): |
| return self._detected_language |
| |
| def get_confidence(self): |
| return 0.99 if self._detected_charset else 0.00 |
| |
| def feed(self, byte_str): |
| for c in byte_str: |
| for coding_sm in self.coding_sm: |
| if not coding_sm or not coding_sm.active: |
| continue |
| coding_state = coding_sm.next_state(c) |
| if coding_state == MachineState.ERROR: |
| coding_sm.active = False |
| self.active_sm_count -= 1 |
| if self.active_sm_count <= 0: |
| self._state = ProbingState.NOT_ME |
| return self.state |
| elif coding_state == MachineState.ITS_ME: |
| self._state = ProbingState.FOUND_IT |
| self._detected_charset = coding_sm.get_coding_state_machine() |
| self._detected_language = coding_sm.language |
| return self.state |
| |
| return self.state |
