gecko-dev/intl/chardet/nsCyrillicDetector.cpp

110 строки
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);
}