/extensions/universalchardet/src/base/nsBig5Prober.cpp

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37
38#include "nsBig5Prober.h"
39#include "nsDebug.h"
40
41void  nsBig5Prober::Reset(void)
42{
43  mCodingSM->Reset(); 
44  mState = eDetecting;
45  mDistributionAnalyser.Reset(mIsPreferredLanguage);
46}
47
48nsProbingState nsBig5Prober::HandleData(const char* aBuf, PRUint32 aLen)
49{
50  NS_ASSERTION(aLen, "HandleData called with empty buffer");
51  nsSMState codingState;
52
53  for (PRUint32 i = 0; i < aLen; i++)
54  {
55    codingState = mCodingSM->NextState(aBuf[i]);
56    if (codingState == eItsMe)
57    {
58      mState = eFoundIt;
59      break;
60    }
61    if (codingState == eStart)
62    {
63      PRUint32 charLen = mCodingSM->GetCurrentCharLen();
64
65      if (i == 0)
66      {
67        mLastChar[1] = aBuf[0];
68        mDistributionAnalyser.HandleOneChar(mLastChar, charLen);
69      }
70      else
71        mDistributionAnalyser.HandleOneChar(aBuf+i-1, charLen);
72    }
73  }
74
75  mLastChar[0] = aBuf[aLen-1];
76
77  if (mState == eDetecting)
78    if (mDistributionAnalyser.GotEnoughData() && GetConfidence() > SHORTCUT_THRESHOLD)
79      mState = eFoundIt;
80
81  return mState;
82}
83
84float nsBig5Prober::GetConfidence(void)
85{
86  float distribCf = mDistributionAnalyser.GetConfidence();
87
88  return (float)distribCf;
89}
90