1 files changed, 136 insertions, 0 deletions
diff --git a/core/fxcodec/jbig2/JBig2_HuffmanTable.cpp b/core/fxcodec/jbig2/JBig2_HuffmanTable.cpp
new file mode 100644
index 0000000000..f4a838eb24
--- /dev/null
+++ b/core/fxcodec/jbig2/JBig2_HuffmanTable.cpp
@@ -0,0 +1,136 @@
+// Copyright 2014 PDFium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
+
+#include "core/fxcodec/jbig2/JBig2_HuffmanTable.h"
+
+#include <algorithm>
+#include <vector>
+
+#include "core/fxcodec/jbig2/JBig2_BitStream.h"
+#include "core/fxcodec/jbig2/JBig2_Define.h"
+#include "core/fxcodec/jbig2/JBig2_HuffmanTable_Standard.h"
+#include "core/include/fxcrt/fx_memory.h"
+
+CJBig2_HuffmanTable::CJBig2_HuffmanTable(const JBig2TableLine* pTable,
+                                         FX_DWORD nLines,
+                                         bool bHTOOB)
+    : m_bOK(true), HTOOB(bHTOOB), NTEMP(nLines) {
+  ParseFromStandardTable(pTable);
+}
+
+CJBig2_HuffmanTable::CJBig2_HuffmanTable(CJBig2_BitStream* pStream)
+    : HTOOB(false), NTEMP(0) {
+  m_bOK = ParseFromCodedBuffer(pStream);
+}
+
+CJBig2_HuffmanTable::~CJBig2_HuffmanTable() {}
+
+void CJBig2_HuffmanTable::ParseFromStandardTable(const JBig2TableLine* pTable) {
+  PREFLEN.resize(NTEMP);
+  RANGELEN.resize(NTEMP);
+  RANGELOW.resize(NTEMP);
+  for (FX_DWORD i = 0; i < NTEMP; ++i) {
+    PREFLEN[i] = pTable[i].PREFLEN;
+    RANGELEN[i] = pTable[i].RANDELEN;
+    RANGELOW[i] = pTable[i].RANGELOW;
+  }
+  InitCodes();
+}
+
+bool CJBig2_HuffmanTable::ParseFromCodedBuffer(CJBig2_BitStream* pStream) {
+  unsigned char cTemp;
+  if (pStream->read1Byte(&cTemp) == -1)
+    return false;
+
+  HTOOB = !!(cTemp & 0x01);
+  unsigned char HTPS = ((cTemp >> 1) & 0x07) + 1;
+  unsigned char HTRS = ((cTemp >> 4) & 0x07) + 1;
+  FX_DWORD HTLOW;
+  FX_DWORD HTHIGH;
+  if (pStream->readInteger(&HTLOW) == -1 ||
+      pStream->readInteger(&HTHIGH) == -1) {
+    return false;
+  }
+
+  const int low = static_cast<int>(HTLOW);
+  const int high = static_cast<int>(HTHIGH);
+  if (low > high)
+    return false;
+
+  ExtendBuffers(false);
+  int cur_low = low;
+  do {
+    if ((pStream->readNBits(HTPS, &PREFLEN[NTEMP]) == -1) ||
+        (pStream->readNBits(HTRS, &RANGELEN[NTEMP]) == -1)) {
+      return false;
+    }
+    RANGELOW[NTEMP] = cur_low;
+    cur_low += (1 << RANGELEN[NTEMP]);
+    ExtendBuffers(true);
+  } while (cur_low < high);
+
+  if (pStream->readNBits(HTPS, &PREFLEN[NTEMP]) == -1)
+    return false;
+
+  RANGELEN[NTEMP] = 32;
+  RANGELOW[NTEMP] = low - 1;
+  ExtendBuffers(true);
+
+  if (pStream->readNBits(HTPS, &PREFLEN[NTEMP]) == -1)
+    return false;
+
+  RANGELEN[NTEMP] = 32;
+  RANGELOW[NTEMP] = high;
+  ExtendBuffers(true);
+
+  if (HTOOB) {
+    if (pStream->readNBits(HTPS, &PREFLEN[NTEMP]) == -1)
+      return false;
+
+    ++NTEMP;
+  }
+
+  InitCodes();
+  return true;
+}
+
+void CJBig2_HuffmanTable::InitCodes() {
+  int lenmax = 0;
+  for (FX_DWORD i = 0; i < NTEMP; ++i)
+    lenmax = std::max(PREFLEN[i], lenmax);
+
+  CODES.resize(NTEMP);
+  std::vector<int> LENCOUNT(lenmax + 1);
+  std::vector<int> FIRSTCODE(lenmax + 1);
+  for (int len : PREFLEN)
+    ++LENCOUNT[len];
+
+  FIRSTCODE[0] = 0;
+  LENCOUNT[0] = 0;
+  for (int i = 1; i <= lenmax; ++i) {
+    FIRSTCODE[i] = (FIRSTCODE[i - 1] + LENCOUNT[i - 1]) << 1;
+    int CURCODE = FIRSTCODE[i];
+    for (FX_DWORD j = 0; j < NTEMP; ++j) {
+      if (PREFLEN[j] == i)
+        CODES[j] = CURCODE++;
+    }
+  }
+}
+
+void CJBig2_HuffmanTable::ExtendBuffers(bool increment) {
+  if (increment)
+    ++NTEMP;
+
+  size_t size = PREFLEN.size();
+  if (NTEMP < size)
+    return;
+
+  size += 16;
+  ASSERT(NTEMP < size);
+  PREFLEN.resize(size);
+  RANGELEN.resize(size);
+  RANGELOW.resize(size);
+}