127 lines
4 KiB
C++
127 lines
4 KiB
C++
/* -*- Mode: C; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
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/* ***** BEGIN LICENSE BLOCK *****
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* Version: MPL 1.1/GPL 2.0/LGPL 2.1
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*
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* The contents of this file are subject to the Mozilla Public License Version
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* 1.1 (the "License"); you may not use this file except in compliance with
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* the License. You may obtain a copy of the License at
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* http://www.mozilla.org/MPL/
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*
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* Software distributed under the License is distributed on an "AS IS" basis,
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* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
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* for the specific language governing rights and limitations under the
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* License.
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*
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* The Original Code is Mozilla Universal charset detector code.
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*
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* The Initial Developer of the Original Code is
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* Netscape Communications Corporation.
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* Portions created by the Initial Developer are Copyright (C) 2001
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* the Initial Developer. All Rights Reserved.
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*
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* Contributor(s):
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* Shy Shalom <shooshX@gmail.com>
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*
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* Alternatively, the contents of this file may be used under the terms of
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* either the GNU General Public License Version 2 or later (the "GPL"), or
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* the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
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* in which case the provisions of the GPL or the LGPL are applicable instead
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* of those above. If you wish to allow use of your version of this file only
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* under the terms of either the GPL or the LGPL, and not to allow others to
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* use your version of this file under the terms of the MPL, indicate your
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* decision by deleting the provisions above and replace them with the notice
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* and other provisions required by the GPL or the LGPL. If you do not delete
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* the provisions above, a recipient may use your version of this file under
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* the terms of any one of the MPL, the GPL or the LGPL.
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*
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* ***** END LICENSE BLOCK ***** */
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#include <stdio.h>
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#include "nsSBCharSetProber.h"
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nsProbingState nsSingleByteCharSetProber::HandleData(const char* aBuf, PRUint32 aLen)
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{
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unsigned char order;
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for (PRUint32 i = 0; i < aLen; i++)
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{
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// Order is in [1-64] but we want 0-63 here.
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order = mModel->charToOrderMap[(unsigned char)aBuf[i]] -1;
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if (order < SYMBOL_CAT_ORDER)
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mTotalChar++;
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if (order < SAMPLE_SIZE)
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{
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mFreqChar++;
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if (mLastOrder < SAMPLE_SIZE)
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{
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mTotalSeqs++;
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if (!mReversed)
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++(mSeqCounters[mModel->precedenceMatrix[mLastOrder*SAMPLE_SIZE+order]]);
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else // reverse the order of the letters in the lookup
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++(mSeqCounters[mModel->precedenceMatrix[order*SAMPLE_SIZE+mLastOrder]]);
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}
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}
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mLastOrder = order;
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}
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if (mState == eDetecting)
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if (mTotalSeqs > SB_ENOUGH_REL_THRESHOLD)
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{
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float cf = GetConfidence();
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if (cf > POSITIVE_SHORTCUT_THRESHOLD)
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mState = eFoundIt;
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else if (cf < NEGATIVE_SHORTCUT_THRESHOLD)
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mState = eNotMe;
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}
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return mState;
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}
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void nsSingleByteCharSetProber::Reset(void)
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{
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mState = eDetecting;
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mLastOrder = 255;
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for (PRUint32 i = 0; i < NUMBER_OF_SEQ_CAT; i++)
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mSeqCounters[i] = 0;
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mTotalSeqs = 0;
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mTotalChar = 0;
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mFreqChar = 0;
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}
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//#define NEGATIVE_APPROACH 1
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float nsSingleByteCharSetProber::GetConfidence(void)
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{
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#ifdef NEGATIVE_APPROACH
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if (mTotalSeqs > 0)
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if (mTotalSeqs > mSeqCounters[NEGATIVE_CAT]*10 )
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return ((float)(mTotalSeqs - mSeqCounters[NEGATIVE_CAT]*10))/mTotalSeqs * mFreqChar / mTotalChar;
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return (float)0.01;
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#else //POSITIVE_APPROACH
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float r;
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if (mTotalSeqs > 0) {
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r = ((float)1.0) * mSeqCounters[POSITIVE_CAT] / mTotalSeqs / mModel->mTypicalPositiveRatio;
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r = r*mFreqChar/mTotalChar;
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if (r >= (float)1.00)
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r = (float)0.99;
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return r;
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}
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return (float)0.01;
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#endif
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}
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const char* nsSingleByteCharSetProber::GetCharSetName()
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{
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if (!mNameProber)
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return mModel->charsetName;
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return mNameProber->GetCharSetName();
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}
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#ifdef DEBUG_chardet
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void nsSingleByteCharSetProber::DumpStatus()
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{
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printf(" SBCS: %1.3f [%s] [%s]\r\n", GetConfidence(), mModel->langName, GetCharSetName());
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}
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#endif
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