Aegisub/vendor/universalchardet/nsMBCSGroupProber.cpp
2014-04-06 07:48:20 -07:00

230 lines
5.9 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
* http://www.mozilla.org/MPL/
*
* 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 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):
* Shy Shalom <shooshX@gmail.com>
* Proofpoint, Inc.
*
* 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
* of those above. If you wish to allow use of your version of this file only
* under the terms of either the GPL or the LGPL, and not to allow others to
* use your version of this file under the terms of the MPL, indicate your
* decision by deleting the provisions above and replace them with the notice
* and other provisions required by the GPL or the LGPL. If you do not delete
* the provisions above, a recipient may use your version of this file under
* the terms of any one of the MPL, the GPL or the LGPL.
*
* ***** END LICENSE BLOCK ***** */
#include <stdio.h>
#include "nsMBCSGroupProber.h"
#include "nsUniversalDetector.h"
#if defined(DEBUG_chardet) || defined(DEBUG_jgmyers)
const char *ProberName[] =
{
"UTF8",
"SJIS",
"EUCJP",
"GB18030",
"EUCKR",
"Big5",
"EUCTW",
};
#endif
nsMBCSGroupProber::nsMBCSGroupProber(PRUint32 aLanguageFilter)
{
for (PRUint32 i = 0; i < NUM_OF_PROBERS; i++)
mProbers[i] = nsnull;
mProbers[0] = new nsUTF8Prober();
if (aLanguageFilter & NS_FILTER_JAPANESE)
{
mProbers[1] = new nsSJISProber(aLanguageFilter == NS_FILTER_JAPANESE);
mProbers[2] = new nsEUCJPProber(aLanguageFilter == NS_FILTER_JAPANESE);
}
if (aLanguageFilter & NS_FILTER_CHINESE_SIMPLIFIED)
mProbers[3] = new nsGB18030Prober(aLanguageFilter == NS_FILTER_CHINESE_SIMPLIFIED);
if (aLanguageFilter & NS_FILTER_KOREAN)
mProbers[4] = new nsEUCKRProber(aLanguageFilter == NS_FILTER_KOREAN);
if (aLanguageFilter & NS_FILTER_CHINESE_TRADITIONAL)
{
mProbers[5] = new nsBig5Prober(aLanguageFilter == NS_FILTER_CHINESE_TRADITIONAL);
mProbers[6] = new nsEUCTWProber(aLanguageFilter == NS_FILTER_CHINESE_TRADITIONAL);
}
Reset();
}
nsMBCSGroupProber::~nsMBCSGroupProber()
{
for (PRUint32 i = 0; i < NUM_OF_PROBERS; i++)
{
delete mProbers[i];
}
}
const char* nsMBCSGroupProber::GetCharSetName()
{
if (mBestGuess == -1)
{
GetConfidence();
if (mBestGuess == -1)
mBestGuess = 0;
}
return mProbers[mBestGuess]->GetCharSetName();
}
void nsMBCSGroupProber::Reset(void)
{
mActiveNum = 0;
for (PRUint32 i = 0; i < NUM_OF_PROBERS; i++)
{
if (mProbers[i])
{
mProbers[i]->Reset();
mIsActive[i] = PR_TRUE;
++mActiveNum;
}
else
mIsActive[i] = PR_FALSE;
}
mBestGuess = -1;
mState = eDetecting;
mKeepNext = 0;
}
nsProbingState nsMBCSGroupProber::HandleData(const char* aBuf, PRUint32 aLen)
{
nsProbingState st;
PRUint32 start = 0;
PRUint32 keepNext = mKeepNext;
//do filtering to reduce load to probers
for (PRUint32 pos = 0; pos < aLen; ++pos)
{
if (aBuf[pos] & 0x80)
{
if (!keepNext)
start = pos;
keepNext = 2;
}
else if (keepNext)
{
if (--keepNext == 0)
{
for (PRUint32 i = 0; i < NUM_OF_PROBERS; i++)
{
if (!mIsActive[i])
continue;
st = mProbers[i]->HandleData(aBuf + start, pos + 1 - start);
if (st == eFoundIt)
{
mBestGuess = i;
mState = eFoundIt;
return mState;
}
}
}
}
}
if (keepNext) {
for (PRUint32 i = 0; i < NUM_OF_PROBERS; i++)
{
if (!mIsActive[i])
continue;
st = mProbers[i]->HandleData(aBuf + start, aLen - start);
if (st == eFoundIt)
{
mBestGuess = i;
mState = eFoundIt;
return mState;
}
}
}
mKeepNext = keepNext;
return mState;
}
float nsMBCSGroupProber::GetConfidence(void)
{
PRUint32 i;
float bestConf = 0.0, cf;
switch (mState)
{
case eFoundIt:
return (float)0.99;
case eNotMe:
return (float)0.01;
default:
for (i = 0; i < NUM_OF_PROBERS; i++)
{
if (!mIsActive[i])
continue;
cf = mProbers[i]->GetConfidence();
if (bestConf < cf)
{
bestConf = cf;
mBestGuess = i;
}
}
}
return bestConf;
}
#ifdef DEBUG_chardet
void nsMBCSGroupProber::DumpStatus()
{
PRUint32 i;
float cf;
GetConfidence();
for (i = 0; i < NUM_OF_PROBERS; i++)
{
if (!mIsActive[i])
printf(" MBCS inactive: [%s] (confidence is too low).\r\n", ProberName[i]);
else
{
cf = mProbers[i]->GetConfidence();
printf(" MBCS %1.3f: [%s]\r\n", cf, ProberName[i]);
}
}
}
#endif
#ifdef DEBUG_jgmyers
void nsMBCSGroupProber::GetDetectorState(nsUniversalDetector::DetectorState (&states)[nsUniversalDetector::NumDetectors], PRUint32 &offset)
{
for (PRUint32 i = 0; i < NUM_OF_PROBERS; ++i) {
states[offset].name = ProberName[i];
states[offset].isActive = mIsActive[i];
states[offset].confidence = mIsActive[i] ? mProbers[i]->GetConfidence() : 0.0;
++offset;
}
}
#endif /* DEBUG_jgmyers */