diff options
Diffstat (limited to 'lib/chardet/sjisprober.py')
-rw-r--r-- | lib/chardet/sjisprober.py | 98 |
1 files changed, 98 insertions, 0 deletions
diff --git a/lib/chardet/sjisprober.py b/lib/chardet/sjisprober.py new file mode 100644 index 0000000..3bcbdb7 --- /dev/null +++ b/lib/chardet/sjisprober.py @@ -0,0 +1,98 @@ +######################## 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 .chardistribution import SJISDistributionAnalysis +from .codingstatemachine import CodingStateMachine +from .enums import MachineState, ProbingState +from .jpcntx import SJISContextAnalysis +from .mbcharsetprober import MultiByteCharSetProber +from .mbcssm import SJIS_SM_MODEL + + +class SJISProber(MultiByteCharSetProber): + def __init__(self): + super().__init__() + self.coding_sm = CodingStateMachine(SJIS_SM_MODEL) + self.distribution_analyzer = SJISDistributionAnalysis() + self.context_analyzer = SJISContextAnalysis() + self.reset() + + def reset(self): + super().reset() + self.context_analyzer.reset() + + @property + def charset_name(self): + return self.context_analyzer.charset_name + + @property + def language(self): + return "Japanese" + + def feed(self, byte_str): + for i, byte in enumerate(byte_str): + coding_state = self.coding_sm.next_state(byte) + if coding_state == MachineState.ERROR: + self.logger.debug( + "%s %s prober hit error at byte %s", + self.charset_name, + self.language, + i, + ) + self._state = ProbingState.NOT_ME + break + if coding_state == MachineState.ITS_ME: + self._state = ProbingState.FOUND_IT + break + if coding_state == MachineState.START: + char_len = self.coding_sm.get_current_charlen() + if i == 0: + self._last_char[1] = byte + self.context_analyzer.feed( + self._last_char[2 - char_len :], char_len + ) + self.distribution_analyzer.feed(self._last_char, char_len) + else: + self.context_analyzer.feed( + byte_str[i + 1 - char_len : i + 3 - char_len], char_len + ) + self.distribution_analyzer.feed(byte_str[i - 1 : i + 1], char_len) + + self._last_char[0] = byte_str[-1] + + if self.state == ProbingState.DETECTING: + if self.context_analyzer.got_enough_data() and ( + self.get_confidence() > self.SHORTCUT_THRESHOLD + ): + self._state = ProbingState.FOUND_IT + + return self.state + + def get_confidence(self): + context_conf = self.context_analyzer.get_confidence() + distrib_conf = self.distribution_analyzer.get_confidence() + return max(context_conf, distrib_conf) |