Clementine-audio-player-Mac.../3rdparty/universalchardet/nsUTF8Prober.cpp

88 lines
2.6 KiB
C++

/* -*- Mode: C; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
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*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* 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):
*
* Alternatively, the contents of this file may be used under the terms of
* either the GNU General Public License Version 2 or later (the "GPL"), or
* the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
* in which case the provisions of the GPL or the LGPL are applicable instead
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* decision by deleting the provisions above and replace them with the notice
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* the provisions above, a recipient may use your version of this file under
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* ***** END LICENSE BLOCK ***** */
#include "nsUTF8Prober.h"
void nsUTF8Prober::Reset(void)
{
mCodingSM->Reset();
mNumOfMBChar = 0;
mState = eDetecting;
}
nsProbingState nsUTF8Prober::HandleData(const char* aBuf, uint32_t aLen)
{
nsSMState codingState;
for (uint32_t i = 0; i < aLen; i++)
{
codingState = mCodingSM->NextState(aBuf[i]);
if (codingState == eItsMe)
{
mState = eFoundIt;
break;
}
if (codingState == eStart)
{
if (mCodingSM->GetCurrentCharLen() >= 2)
mNumOfMBChar++;
}
}
if (mState == eDetecting)
if (GetConfidence() > SHORTCUT_THRESHOLD)
mState = eFoundIt;
return mState;
}
#define ONE_CHAR_PROB (float)0.50
float nsUTF8Prober::GetConfidence(void)
{
float unlike = (float)0.99;
if (mNumOfMBChar < 6)
{
for (uint32_t i = 0; i < mNumOfMBChar; i++)
unlike *= ONE_CHAR_PROB;
return (float)1.0 - unlike;
}
else
return (float)0.99;
}