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Diffstat (limited to 'requests/packages/chardet/latin1prober.py')
| -rw-r--r-- | requests/packages/chardet/latin1prober.py | 139 |
1 files changed, 139 insertions, 0 deletions
diff --git a/requests/packages/chardet/latin1prober.py b/requests/packages/chardet/latin1prober.py new file mode 100644 index 0000000..ad695f5 --- /dev/null +++ b/requests/packages/chardet/latin1prober.py @@ -0,0 +1,139 @@ +######################## BEGIN LICENSE BLOCK ######################## +# The Original Code is Mozilla Universal charset detector code. +# +# The Initial Developer of the Original Code is +# Netscape Communications Corporation. +# Portions created by the Initial Developer are Copyright (C) 2001 +# the Initial Developer. All Rights Reserved. +# +# Contributor(s): +# Mark Pilgrim - port to Python +# Shy Shalom - original C code +# +# 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 .constants import eNotMe +from .compat import wrap_ord + +FREQ_CAT_NUM = 4 + +UDF = 0 # undefined +OTH = 1 # other +ASC = 2 # ascii capital letter +ASS = 3 # ascii small letter +ACV = 4 # accent capital vowel +ACO = 5 # accent capital other +ASV = 6 # accent small vowel +ASO = 7 # accent small other +CLASS_NUM = 8 # total classes + +Latin1_CharToClass = ( + OTH, OTH, OTH, OTH, OTH, OTH, OTH, OTH, # 00 - 07 + OTH, OTH, OTH, OTH, OTH, OTH, OTH, OTH, # 08 - 0F + OTH, OTH, OTH, OTH, OTH, OTH, OTH, OTH, # 10 - 17 + OTH, OTH, OTH, OTH, OTH, OTH, OTH, OTH, # 18 - 1F + OTH, OTH, OTH, OTH, OTH, OTH, OTH, OTH, # 20 - 27 + OTH, OTH, OTH, OTH, OTH, OTH, OTH, OTH, # 28 - 2F + OTH, OTH, OTH, OTH, OTH, OTH, OTH, OTH, # 30 - 37 + OTH, OTH, OTH, OTH, OTH, OTH, OTH, OTH, # 38 - 3F + OTH, ASC, ASC, ASC, ASC, ASC, ASC, ASC, # 40 - 47 + ASC, ASC, ASC, ASC, ASC, ASC, ASC, ASC, # 48 - 4F + ASC, ASC, ASC, ASC, ASC, ASC, ASC, ASC, # 50 - 57 + ASC, ASC, ASC, OTH, OTH, OTH, OTH, OTH, # 58 - 5F + OTH, ASS, ASS, ASS, ASS, ASS, ASS, ASS, # 60 - 67 + ASS, ASS, ASS, ASS, ASS, ASS, ASS, ASS, # 68 - 6F + ASS, ASS, ASS, ASS, ASS, ASS, ASS, ASS, # 70 - 77 + ASS, ASS, ASS, OTH, OTH, OTH, OTH, OTH, # 78 - 7F + OTH, UDF, OTH, ASO, OTH, OTH, OTH, OTH, # 80 - 87 + OTH, OTH, ACO, OTH, ACO, UDF, ACO, UDF, # 88 - 8F + UDF, OTH, OTH, OTH, OTH, OTH, OTH, OTH, # 90 - 97 + OTH, OTH, ASO, OTH, ASO, UDF, ASO, ACO, # 98 - 9F + OTH, OTH, OTH, OTH, OTH, OTH, OTH, OTH, # A0 - A7 + OTH, OTH, OTH, OTH, OTH, OTH, OTH, OTH, # A8 - AF + OTH, OTH, OTH, OTH, OTH, OTH, OTH, OTH, # B0 - B7 + OTH, OTH, OTH, OTH, OTH, OTH, OTH, OTH, # B8 - BF + ACV, ACV, ACV, ACV, ACV, ACV, ACO, ACO, # C0 - C7 + ACV, ACV, ACV, ACV, ACV, ACV, ACV, ACV, # C8 - CF + ACO, ACO, ACV, ACV, ACV, ACV, ACV, OTH, # D0 - D7 + ACV, ACV, ACV, ACV, ACV, ACO, ACO, ACO, # D8 - DF + ASV, ASV, ASV, ASV, ASV, ASV, ASO, ASO, # E0 - E7 + ASV, ASV, ASV, ASV, ASV, ASV, ASV, ASV, # E8 - EF + ASO, ASO, ASV, ASV, ASV, ASV, ASV, OTH, # F0 - F7 + ASV, ASV, ASV, ASV, ASV, ASO, ASO, ASO, # F8 - FF +) + +# 0 : illegal +# 1 : very unlikely +# 2 : normal +# 3 : very likely +Latin1ClassModel = ( + # UDF OTH ASC ASS ACV ACO ASV ASO + 0, 0, 0, 0, 0, 0, 0, 0, # UDF + 0, 3, 3, 3, 3, 3, 3, 3, # OTH + 0, 3, 3, 3, 3, 3, 3, 3, # ASC + 0, 3, 3, 3, 1, 1, 3, 3, # ASS + 0, 3, 3, 3, 1, 2, 1, 2, # ACV + 0, 3, 3, 3, 3, 3, 3, 3, # ACO + 0, 3, 1, 3, 1, 1, 1, 3, # ASV + 0, 3, 1, 3, 1, 1, 3, 3, # ASO +) + + +class Latin1Prober(CharSetProber): + def __init__(self): + CharSetProber.__init__(self) + self.reset() + + def reset(self): + self._mLastCharClass = OTH + self._mFreqCounter = [0] * FREQ_CAT_NUM + CharSetProber.reset(self) + + def get_charset_name(self): + return "windows-1252" + + def feed(self, aBuf): + aBuf = self.filter_with_english_letters(aBuf) + for c in aBuf: + charClass = Latin1_CharToClass[wrap_ord(c)] + freq = Latin1ClassModel[(self._mLastCharClass * CLASS_NUM) + + charClass] + if freq == 0: + self._mState = eNotMe + break + self._mFreqCounter[freq] += 1 + self._mLastCharClass = charClass + + return self.get_state() + + def get_confidence(self): + if self.get_state() == eNotMe: + return 0.01 + + total = sum(self._mFreqCounter) + if total < 0.01: + confidence = 0.0 + else: + confidence = ((self._mFreqCounter[3] / total) + - (self._mFreqCounter[1] * 20.0 / total)) + if confidence < 0.0: + confidence = 0.0 + # lower the confidence of latin1 so that other more accurate + # detector can take priority. + confidence = confidence * 0.5 + return confidence |