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/* -*- 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.org 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) 1998 |
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* the Initial Developer. All Rights Reserved. |
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* |
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* Contributor(s): |
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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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|
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// for S-JIS encoding, obeserve characteristic: |
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// 1, kana character (or hankaku?) often have hight frequency of appereance |
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// 2, kana character often exist in group |
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// 3, certain combination of kana is never used in japanese language |
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|
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#include "nsSJISProber.h" |
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|
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void nsSJISProber::Reset(void) |
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{ |
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mCodingSM->Reset(); |
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mState = eDetecting; |
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mContextAnalyser.Reset(); |
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mDistributionAnalyser.Reset(); |
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} |
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|
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nsProbingState nsSJISProber::HandleData(const char* aBuf, PRUint32 aLen) |
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{ |
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nsSMState codingState; |
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|
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for (PRUint32 i = 0; i < aLen; i++) |
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{ |
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codingState = mCodingSM->NextState(aBuf[i]); |
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if (codingState == eItsMe) |
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{ |
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mState = eFoundIt; |
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break; |
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} |
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if (codingState == eStart) |
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{ |
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PRUint32 charLen = mCodingSM->GetCurrentCharLen(); |
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if (i == 0) |
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{ |
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mLastChar[1] = aBuf[0]; |
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mContextAnalyser.HandleOneChar(mLastChar+2-charLen, charLen); |
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mDistributionAnalyser.HandleOneChar(mLastChar, charLen); |
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} |
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else |
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{ |
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mContextAnalyser.HandleOneChar(aBuf+i+1-charLen, charLen); |
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mDistributionAnalyser.HandleOneChar(aBuf+i-1, charLen); |
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} |
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} |
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} |
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|
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mLastChar[0] = aBuf[aLen-1]; |
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|
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if (mState == eDetecting) |
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if (mContextAnalyser.GotEnoughData() && GetConfidence() > SHORTCUT_THRESHOLD) |
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mState = eFoundIt; |
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|
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return mState; |
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} |
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|
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float nsSJISProber::GetConfidence(void) |
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{ |
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float contxtCf = mContextAnalyser.GetConfidence(mIsPreferredLanguage); |
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float distribCf = mDistributionAnalyser.GetConfidence(mIsPreferredLanguage); |
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|
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return (contxtCf > distribCf ? contxtCf : distribCf); |
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} |
