Aegisub/aegisub/vendor/universalchardet/nsUTF8Prober.cpp
2014-03-11 08:59:45 -07:00

87 lines
2.6 KiB
C++

/* -*- Mode: C; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* ***** BEGIN LICENSE BLOCK *****
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* The contents of this file are subject to the Mozilla Public License Version
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*
* The Original Code is mozilla.org code.
*
* The Initial Developer of the Original Code is
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* the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
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#include "nsUTF8Prober.h"
void nsUTF8Prober::Reset(void)
{
mCodingSM->Reset();
mNumOfMBChar = 0;
mState = eDetecting;
}
nsProbingState nsUTF8Prober::HandleData(const char* aBuf, PRUint32 aLen)
{
nsSMState codingState;
for (PRUint32 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 (PRUint32 i = 0; i < mNumOfMBChar; i++)
unlike *= ONE_CHAR_PROB;
return (float)1.0 - unlike;
}
else
return (float)0.99;
}