diff -r 000000000000 -r 6474c204b198 extensions/universalchardet/src/base/nsSBCharSetProber.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/extensions/universalchardet/src/base/nsSBCharSetProber.cpp	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,93 @@
+/* -*- 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 <stdio.h>
+#include "nsSBCharSetProber.h"
+
+nsProbingState nsSingleByteCharSetProber::HandleData(const char* aBuf, uint32_t aLen)
+{
+  unsigned char order;
+
+  for (uint32_t i = 0; i < aLen; i++)
+  {
+    order = mModel->charToOrderMap[(unsigned char)aBuf[i]];
+
+    if (order < SYMBOL_CAT_ORDER)
+      mTotalChar++;
+    if (order < SAMPLE_SIZE)
+    {
+        mFreqChar++;
+
+      if (mLastOrder < SAMPLE_SIZE)
+      {
+        mTotalSeqs++;
+        if (!mReversed)
+          ++(mSeqCounters[mModel->precedenceMatrix[mLastOrder*SAMPLE_SIZE+order]]);
+        else // reverse the order of the letters in the lookup
+          ++(mSeqCounters[mModel->precedenceMatrix[order*SAMPLE_SIZE+mLastOrder]]);
+      }
+    }
+    mLastOrder = order;
+  }
+
+  if (mState == eDetecting)
+    if (mTotalSeqs > SB_ENOUGH_REL_THRESHOLD)
+    {
+      float cf = GetConfidence();
+      if (cf > POSITIVE_SHORTCUT_THRESHOLD)
+        mState = eFoundIt;
+      else if (cf < NEGATIVE_SHORTCUT_THRESHOLD)
+        mState = eNotMe;
+    }
+
+  return mState;
+}
+
+void  nsSingleByteCharSetProber::Reset(void)
+{
+  mState = eDetecting;
+  mLastOrder = 255;
+  for (uint32_t i = 0; i < NUMBER_OF_SEQ_CAT; i++)
+    mSeqCounters[i] = 0;
+  mTotalSeqs = 0;
+  mTotalChar = 0;
+  mFreqChar = 0;
+}
+
+//#define NEGATIVE_APPROACH 1
+
+float nsSingleByteCharSetProber::GetConfidence(void)
+{
+#ifdef NEGATIVE_APPROACH
+  if (mTotalSeqs > 0)
+    if (mTotalSeqs > mSeqCounters[NEGATIVE_CAT]*10 )
+      return ((float)(mTotalSeqs - mSeqCounters[NEGATIVE_CAT]*10))/mTotalSeqs * mFreqChar / mTotalChar;
+  return (float)0.01;
+#else  //POSITIVE_APPROACH
+  float r;
+
+  if (mTotalSeqs > 0) {
+    r = ((float)1.0) * mSeqCounters[POSITIVE_CAT] / mTotalSeqs / mModel->mTypicalPositiveRatio;
+    r = r*mFreqChar/mTotalChar;
+    if (r >= (float)1.00)
+      r = (float)0.99;
+    return r;
+  }
+  return (float)0.01;
+#endif
+}
+
+const char* nsSingleByteCharSetProber::GetCharSetName() 
+{
+  if (!mNameProber)
+    return mModel->charsetName;
+  return mNameProber->GetCharSetName();
+}
+
+#ifdef DEBUG_chardet
+void nsSingleByteCharSetProber::DumpStatus()
+{
+  printf("  SBCS: %1.3f [%s]\r\n", GetConfidence(), GetCharSetName());
+}
+#endif