File indexing completed on 2024-04-28 03:53:02

 /*  -*- C++ -*-
     SPDX-FileCopyrightText: 1998 Netscape Communications Corporation <developer@mozilla.org>
 
     SPDX-License-Identifier: MIT
 */
 
 #include "ChineseGroupProber.h"
 
 #include "UnicodeGroupProber.h"
 #include "nsBig5Prober.h"
 #include "nsGB2312Prober.h"
 
 #include <stdio.h>
 #include <stdlib.h>
 
 namespace kencodingprober
 {
 #ifdef DEBUG_PROBE
 static const char *const ProberName[] = {
     "Unicode",
     "GB18030",
     "Big5",
 };
 
 #endif
 
 ChineseGroupProber::ChineseGroupProber()
 {
     mProbers[0] = new UnicodeGroupProber();
     mProbers[1] = new nsGB18030Prober();
     mProbers[2] = new nsBig5Prober();
     Reset();
 }
 
 ChineseGroupProber::~ChineseGroupProber()
 {
     for (unsigned int i = 0; i < CN_NUM_OF_PROBERS; i++) {
         delete mProbers[i];
     }
 }
 
 const char *ChineseGroupProber::GetCharSetName()
 {
     if (mBestGuess == -1) {
         GetConfidence();
         if (mBestGuess == -1) {
             mBestGuess = 1; // assume it's GB18030
         }
     }
     return mProbers[mBestGuess]->GetCharSetName();
 }
 
 void ChineseGroupProber::Reset(void)
 {
     mActiveNum = 0;
     for (unsigned int i = 0; i < CN_NUM_OF_PROBERS; i++) {
         if (mProbers[i]) {
             mProbers[i]->Reset();
             mIsActive[i] = true;
             ++mActiveNum;
         } else {
             mIsActive[i] = false;
         }
     }
     mBestGuess = -1;
     mState = eDetecting;
 }
 
 nsProbingState ChineseGroupProber::HandleData(const char *aBuf, unsigned int aLen)
 {
     nsProbingState st;
     unsigned int i;
 
     // do filtering to reduce load to probers
     char *highbyteBuf;
     char *hptr;
     bool keepNext = true; // assume previous is not ascii, it will do no harm except add some noise
     hptr = highbyteBuf = (char *)malloc(aLen);
     if (!hptr) {
         return mState;
     }
     for (i = 0; i < aLen; ++i) {
         if (aBuf[i] & 0x80) {
             *hptr++ = aBuf[i];
             keepNext = true;
         } else {
             // if previous is highbyte, keep this even it is an ASCII
             if (keepNext) {
                 *hptr++ = aBuf[i];
                 keepNext = false;
             }
         }
     }
 
     for (i = 0; i < CN_NUM_OF_PROBERS; ++i) {
         if (!mIsActive[i]) {
             continue;
         }
         st = mProbers[i]->HandleData(highbyteBuf, hptr - highbyteBuf);
         if (st == eFoundIt) {
             mBestGuess = i;
             mState = eFoundIt;
             break;
         } else if (st == eNotMe) {
             mIsActive[i] = false;
             --mActiveNum;
             if (mActiveNum == 0) {
                 mState = eNotMe;
                 break;
             }
         }
     }
 
     free(highbyteBuf);
 
     return mState;
 }
 
 float ChineseGroupProber::GetConfidence(void)
 {
     unsigned int i;
     float bestConf = 0.0;
     float cf;
 
     switch (mState) {
     case eFoundIt:
         return (float)0.99;
     case eNotMe:
         return (float)0.01;
     default:
         for (i = 0; i < CN_NUM_OF_PROBERS; ++i) {
             if (!mIsActive[i]) {
                 continue;
             }
             cf = mProbers[i]->GetConfidence();
             if (bestConf < cf) {
                 bestConf = cf;
                 mBestGuess = i;
             }
         }
     }
     return bestConf;
 }
 
 #ifdef DEBUG_PROBE
 void ChineseGroupProber::DumpStatus()
 {
     unsigned int i;
     float cf;
 
     GetConfidence();
     for (i = 0; i < CN_NUM_OF_PROBERS; i++) {
         if (!mIsActive[i]) {
             printf("  Chinese group inactive: [%s] (confidence is too low).\r\n", ProberName[i]);
         } else {
             cf = mProbers[i]->GetConfidence();
             printf("  Chinese group %1.3f: [%s]\r\n", cf, ProberName[i]);
         }
     }
 }
 #endif
 }