gecko-dev/intl/chardet/nsCyrillicDetector.cpp

126 lines
3.3 KiB
C++

/* -*- Mode: C; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#include "nscore.h"
#include "nsCyrillicProb.h"
#include <stdio.h>
#include "nsCOMPtr.h"
#include "nsISupports.h"
#include "nsICharsetDetector.h"
#include "nsICharsetDetectionObserver.h"
#include "nsIStringCharsetDetector.h"
#include "nsCyrillicDetector.h"
//----------------------------------------------------------------------
// Interface nsISupports [implementation]
NS_IMPL_ISUPPORTS(nsCyrXPCOMDetector, nsICharsetDetector)
void nsCyrillicDetector::HandleData(const char* aBuf, uint32_t aLen)
{
uint8_t cls;
const char* b;
uint32_t i;
if(mDone)
return;
for(i=0, b=aBuf;i<aLen;i++,b++)
{
for(unsigned j=0;j<mItems;j++)
{
if( 0x80 & *b)
cls = mCyrillicClass[j][(*b) & 0x7F];
else
cls = 0;
NS_ASSERTION( cls <= 32 , "illegal character class");
mProb[j] += gCyrillicProb[mLastCls[j]][cls];
mLastCls[j] = cls;
}
}
// We now only based on the first block we receive
DataEnd();
}
//---------------------------------------------------------------------
#define THRESHOLD_RATIO 1.5f
void nsCyrillicDetector::DataEnd()
{
uint32_t max=0;
uint8_t maxIdx=0;
uint8_t j;
if(mDone)
return;
for(j=0;j<mItems;j++) {
if(mProb[j] > max)
{
max = mProb[j];
maxIdx= j;
}
}
if( 0 == max ) // if we didn't get any 8 bits data
return;
#ifdef DEBUG
for(j=0;j<mItems;j++)
printf("Charset %s->\t%d\n", mCharsets[j], mProb[j]);
#endif
this->Report(mCharsets[maxIdx]);
mDone = true;
}
//---------------------------------------------------------------------
nsCyrXPCOMDetector:: nsCyrXPCOMDetector(uint8_t aItems,
const uint8_t ** aCyrillicClass,
const char **aCharsets)
: nsCyrillicDetector(aItems, aCyrillicClass, aCharsets)
{
mObserver = nullptr;
}
//---------------------------------------------------------------------
nsCyrXPCOMDetector::~nsCyrXPCOMDetector()
{
}
//---------------------------------------------------------------------
NS_IMETHODIMP nsCyrXPCOMDetector::Init(
nsICharsetDetectionObserver* aObserver)
{
NS_ASSERTION(mObserver == nullptr , "Init twice");
if(nullptr == aObserver)
return NS_ERROR_ILLEGAL_VALUE;
mObserver = aObserver;
return NS_OK;
}
//----------------------------------------------------------
NS_IMETHODIMP nsCyrXPCOMDetector::DoIt(
const char* aBuf, uint32_t aLen, bool* oDontFeedMe)
{
NS_ASSERTION(mObserver != nullptr , "have not init yet");
if((nullptr == aBuf) || (nullptr == oDontFeedMe))
return NS_ERROR_ILLEGAL_VALUE;
this->HandleData(aBuf, aLen);
*oDontFeedMe = false;
return NS_OK;
}
//----------------------------------------------------------
NS_IMETHODIMP nsCyrXPCOMDetector::Done()
{
NS_ASSERTION(mObserver != nullptr , "have not init yet");
this->DataEnd();
return NS_OK;
}
//----------------------------------------------------------
void nsCyrXPCOMDetector::Report(const char* aCharset)
{
NS_ASSERTION(mObserver != nullptr , "have not init yet");
mObserver->Notify(aCharset, eBestAnswer);
}