| Index: core/src/fxcodec/jbig2/JBig2_BitStream.cpp
|
| diff --git a/core/src/fxcodec/jbig2/JBig2_BitStream.cpp b/core/src/fxcodec/jbig2/JBig2_BitStream.cpp
|
| new file mode 100644
|
| index 0000000000000000000000000000000000000000..4a4ed992c7fe387045546d7f4be81b8cd1e699f2
|
| --- /dev/null
|
| +++ b/core/src/fxcodec/jbig2/JBig2_BitStream.cpp
|
| @@ -0,0 +1,178 @@
|
| +// Copyright 2015 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 "JBig2_BitStream.h"
|
| +
|
| +#include <algorithm>
|
| +
|
| +CJBig2_BitStream::CJBig2_BitStream(const uint8_t* pBuffer, FX_DWORD dwLength)
|
| + : m_pBuf(pBuffer), m_dwLength(dwLength), m_dwByteIdx(0), m_dwBitIdx(0) {
|
| + if (m_dwLength > 256 * 1024 * 1024) {
|
| + m_dwLength = 0;
|
| + m_pBuf = nullptr;
|
| + }
|
| +}
|
| +
|
| +CJBig2_BitStream::~CJBig2_BitStream() {
|
| +}
|
| +
|
| +int32_t CJBig2_BitStream::readNBits(FX_DWORD dwBits, FX_DWORD* dwResult) {
|
| + FX_DWORD dwBitPos = getBitPos();
|
| + if (dwBitPos > LengthInBits())
|
| + return -1;
|
| +
|
| + *dwResult = 0;
|
| + if (dwBitPos + dwBits <= LengthInBits())
|
| + dwBitPos = dwBits;
|
| + else
|
| + dwBitPos = LengthInBits() - dwBitPos;
|
| +
|
| + for (; dwBitPos > 0; --dwBitPos) {
|
| + *dwResult =
|
| + (*dwResult << 1) | ((m_pBuf[m_dwByteIdx] >> (7 - m_dwBitIdx)) & 0x01);
|
| + AdvanceBit();
|
| + }
|
| + return 0;
|
| +}
|
| +
|
| +int32_t CJBig2_BitStream::readNBits(FX_DWORD dwBits, int32_t* nResult) {
|
| + FX_DWORD dwBitPos = getBitPos();
|
| + if (dwBitPos > LengthInBits())
|
| + return -1;
|
| +
|
| + *nResult = 0;
|
| + if (dwBitPos + dwBits <= LengthInBits())
|
| + dwBitPos = dwBits;
|
| + else
|
| + dwBitPos = LengthInBits() - dwBitPos;
|
| +
|
| + for (; dwBitPos > 0; --dwBitPos) {
|
| + *nResult =
|
| + (*nResult << 1) | ((m_pBuf[m_dwByteIdx] >> (7 - m_dwBitIdx)) & 0x01);
|
| + AdvanceBit();
|
| + }
|
| + return 0;
|
| +}
|
| +
|
| +int32_t CJBig2_BitStream::read1Bit(FX_DWORD* dwResult) {
|
| + if (!IsInBound())
|
| + return -1;
|
| +
|
| + *dwResult = (m_pBuf[m_dwByteIdx] >> (7 - m_dwBitIdx)) & 0x01;
|
| + AdvanceBit();
|
| + return 0;
|
| +}
|
| +
|
| +int32_t CJBig2_BitStream::read1Bit(FX_BOOL* bResult) {
|
| + if (!IsInBound())
|
| + return -1;
|
| +
|
| + *bResult = (m_pBuf[m_dwByteIdx] >> (7 - m_dwBitIdx)) & 0x01;
|
| + AdvanceBit();
|
| + return 0;
|
| +}
|
| +
|
| +int32_t CJBig2_BitStream::read1Byte(uint8_t* cResult) {
|
| + if (!IsInBound())
|
| + return -1;
|
| +
|
| + *cResult = m_pBuf[m_dwByteIdx];
|
| + ++m_dwByteIdx;
|
| + return 0;
|
| +}
|
| +
|
| +int32_t CJBig2_BitStream::readInteger(FX_DWORD* dwResult) {
|
| + if (m_dwByteIdx + 3 >= m_dwLength)
|
| + return -1;
|
| +
|
| + *dwResult = (m_pBuf[m_dwByteIdx] << 24) | (m_pBuf[m_dwByteIdx + 1] << 16) |
|
| + (m_pBuf[m_dwByteIdx + 2] << 8) | m_pBuf[m_dwByteIdx + 3];
|
| + m_dwByteIdx += 4;
|
| + return 0;
|
| +}
|
| +
|
| +int32_t CJBig2_BitStream::readShortInteger(FX_WORD* dwResult) {
|
| + if (m_dwByteIdx + 1 >= m_dwLength)
|
| + return -1;
|
| +
|
| + *dwResult = (m_pBuf[m_dwByteIdx] << 8) | m_pBuf[m_dwByteIdx + 1];
|
| + m_dwByteIdx += 2;
|
| + return 0;
|
| +}
|
| +
|
| +void CJBig2_BitStream::alignByte() {
|
| + if (m_dwBitIdx != 0) {
|
| + ++m_dwByteIdx;
|
| + m_dwBitIdx = 0;
|
| + }
|
| +}
|
| +
|
| +uint8_t CJBig2_BitStream::getCurByte() const {
|
| + return IsInBound() ? m_pBuf[m_dwByteIdx] : 0;
|
| +}
|
| +
|
| +void CJBig2_BitStream::incByteIdx() {
|
| + if (IsInBound())
|
| + ++m_dwByteIdx;
|
| +}
|
| +
|
| +uint8_t CJBig2_BitStream::getCurByte_arith() const {
|
| + return IsInBound() ? m_pBuf[m_dwByteIdx] : 0xFF;
|
| +}
|
| +
|
| +uint8_t CJBig2_BitStream::getNextByte_arith() const {
|
| + return m_dwByteIdx + 1 < m_dwLength ? m_pBuf[m_dwByteIdx + 1] : 0xFF;
|
| +}
|
| +
|
| +FX_DWORD CJBig2_BitStream::getOffset() const {
|
| + return m_dwByteIdx;
|
| +}
|
| +
|
| +void CJBig2_BitStream::setOffset(FX_DWORD dwOffset) {
|
| + m_dwByteIdx = std::min(dwOffset, m_dwLength);
|
| +}
|
| +
|
| +FX_DWORD CJBig2_BitStream::getBitPos() const {
|
| + return (m_dwByteIdx << 3) + m_dwBitIdx;
|
| +}
|
| +
|
| +void CJBig2_BitStream::setBitPos(FX_DWORD dwBitPos) {
|
| + m_dwByteIdx = dwBitPos >> 3;
|
| + m_dwBitIdx = dwBitPos & 7;
|
| +}
|
| +
|
| +const uint8_t* CJBig2_BitStream::getBuf() const {
|
| + return m_pBuf;
|
| +}
|
| +
|
| +const uint8_t* CJBig2_BitStream::getPointer() const {
|
| + return m_pBuf + m_dwByteIdx;
|
| +}
|
| +
|
| +void CJBig2_BitStream::offset(FX_DWORD dwOffset) {
|
| + m_dwByteIdx += dwOffset;
|
| +}
|
| +
|
| +FX_DWORD CJBig2_BitStream::getByteLeft() const {
|
| + return m_dwLength - m_dwByteIdx;
|
| +}
|
| +
|
| +void CJBig2_BitStream::AdvanceBit() {
|
| + if (m_dwBitIdx == 7) {
|
| + ++m_dwByteIdx;
|
| + m_dwBitIdx = 0;
|
| + } else {
|
| + ++m_dwBitIdx;
|
| + }
|
| +}
|
| +
|
| +bool CJBig2_BitStream::IsInBound() const {
|
| + return m_dwByteIdx < m_dwLength;
|
| +}
|
| +
|
| +FX_DWORD CJBig2_BitStream::LengthInBits() const {
|
| + return m_dwLength << 3;
|
| +}
|
|
|