| // 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/codec/ccodec_flatemodule.h" |
| |
| #include <algorithm> |
| #include <limits> |
| #include <memory> |
| #include <utility> |
| #include <vector> |
| |
| #include "core/fxcodec/codec/ccodec_scanlinedecoder.h" |
| #include "core/fxcodec/fx_codec.h" |
| #include "core/fxcrt/fx_extension.h" |
| #include "third_party/base/numerics/safe_conversions.h" |
| #include "third_party/base/ptr_util.h" |
| #include "third_party/base/span.h" |
| |
| #if defined(USE_SYSTEM_ZLIB) |
| #include <zlib.h> |
| #else |
| #include "third_party/zlib/zlib.h" |
| #endif |
| |
| extern "C" { |
| |
| static void* my_alloc_func(void* opaque, |
| unsigned int items, |
| unsigned int size) { |
| return FX_Alloc2D(uint8_t, items, size); |
| } |
| |
| static void my_free_func(void* opaque, void* address) { |
| FX_Free(address); |
| } |
| |
| } // extern "C" |
| |
| namespace { |
| |
| static constexpr uint32_t kMaxTotalOutSize = 1024 * 1024 * 1024; // 1 GiB |
| |
| uint32_t FlateGetPossiblyTruncatedTotalOut(z_stream* context) { |
| return std::min(pdfium::base::saturated_cast<uint32_t>(context->total_out), |
| kMaxTotalOutSize); |
| } |
| |
| uint32_t FlateGetPossiblyTruncatedTotalIn(z_stream* context) { |
| return pdfium::base::saturated_cast<uint32_t>(context->total_in); |
| } |
| |
| bool FlateCompress(unsigned char* dest_buf, |
| unsigned long* dest_size, |
| const unsigned char* src_buf, |
| uint32_t src_size) { |
| return compress(dest_buf, dest_size, src_buf, src_size) == Z_OK; |
| } |
| |
| z_stream* FlateInit() { |
| z_stream* p = FX_Alloc(z_stream, 1); |
| p->zalloc = my_alloc_func; |
| p->zfree = my_free_func; |
| inflateInit(p); |
| return p; |
| } |
| |
| void FlateInput(z_stream* context, pdfium::span<const uint8_t> src_buf) { |
| context->next_in = const_cast<unsigned char*>(src_buf.data()); |
| context->avail_in = static_cast<uint32_t>(src_buf.size()); |
| } |
| |
| uint32_t FlateOutput(z_stream* context, |
| unsigned char* dest_buf, |
| uint32_t dest_size) { |
| context->next_out = dest_buf; |
| context->avail_out = dest_size; |
| uint32_t pre_pos = FlateGetPossiblyTruncatedTotalOut(context); |
| int ret = inflate(static_cast<z_stream*>(context), Z_SYNC_FLUSH); |
| |
| uint32_t post_pos = FlateGetPossiblyTruncatedTotalOut(context); |
| ASSERT(post_pos >= pre_pos); |
| |
| uint32_t written = post_pos - pre_pos; |
| if (written < dest_size) |
| memset(dest_buf + written, '\0', dest_size - written); |
| |
| return ret; |
| } |
| |
| uint32_t FlateGetAvailOut(z_stream* context) { |
| return context->avail_out; |
| } |
| |
| void FlateEnd(z_stream* context) { |
| inflateEnd(context); |
| FX_Free(context); |
| } |
| |
| // For use with std::unique_ptr<z_stream>. |
| struct FlateDeleter { |
| inline void operator()(z_stream* context) { FlateEnd(context); } |
| }; |
| |
| class CLZWDecoder { |
| public: |
| int Decode(uint8_t* output, |
| uint32_t& outlen, |
| const uint8_t* input, |
| uint32_t& size, |
| bool bEarlyChange); |
| |
| private: |
| void AddCode(uint32_t prefix_code, uint8_t append_char); |
| void DecodeString(uint32_t code); |
| |
| uint32_t m_InPos; |
| uint32_t m_OutPos; |
| uint8_t* m_pOutput; |
| const uint8_t* m_pInput; |
| bool m_Early; |
| uint32_t m_nCodes; |
| uint32_t m_StackLen; |
| int m_CodeLen; |
| uint32_t m_CodeArray[5021]; |
| uint8_t m_DecodeStack[4000]; |
| }; |
| |
| void CLZWDecoder::AddCode(uint32_t prefix_code, uint8_t append_char) { |
| if (m_nCodes + m_Early == 4094) { |
| return; |
| } |
| m_CodeArray[m_nCodes++] = (prefix_code << 16) | append_char; |
| if (m_nCodes + m_Early == 512 - 258) { |
| m_CodeLen = 10; |
| } else if (m_nCodes + m_Early == 1024 - 258) { |
| m_CodeLen = 11; |
| } else if (m_nCodes + m_Early == 2048 - 258) { |
| m_CodeLen = 12; |
| } |
| } |
| |
| void CLZWDecoder::DecodeString(uint32_t code) { |
| while (1) { |
| int index = code - 258; |
| if (index < 0 || index >= (int)m_nCodes) { |
| break; |
| } |
| uint32_t data = m_CodeArray[index]; |
| if (m_StackLen >= sizeof(m_DecodeStack)) { |
| return; |
| } |
| m_DecodeStack[m_StackLen++] = (uint8_t)data; |
| code = data >> 16; |
| } |
| if (m_StackLen >= sizeof(m_DecodeStack)) { |
| return; |
| } |
| m_DecodeStack[m_StackLen++] = (uint8_t)code; |
| } |
| |
| int CLZWDecoder::Decode(uint8_t* dest_buf, |
| uint32_t& dest_size, |
| const uint8_t* src_buf, |
| uint32_t& src_size, |
| bool bEarlyChange) { |
| m_CodeLen = 9; |
| m_InPos = 0; |
| m_OutPos = 0; |
| m_pInput = src_buf; |
| m_pOutput = dest_buf; |
| m_Early = bEarlyChange ? 1 : 0; |
| m_nCodes = 0; |
| uint32_t old_code = 0xFFFFFFFF; |
| uint8_t last_char = 0; |
| while (1) { |
| if (m_InPos + m_CodeLen > src_size * 8) { |
| break; |
| } |
| int byte_pos = m_InPos / 8; |
| int bit_pos = m_InPos % 8, bit_left = m_CodeLen; |
| uint32_t code = 0; |
| if (bit_pos) { |
| bit_left -= 8 - bit_pos; |
| code = (m_pInput[byte_pos++] & ((1 << (8 - bit_pos)) - 1)) << bit_left; |
| } |
| if (bit_left < 8) { |
| code |= m_pInput[byte_pos] >> (8 - bit_left); |
| } else { |
| bit_left -= 8; |
| code |= m_pInput[byte_pos++] << bit_left; |
| if (bit_left) { |
| code |= m_pInput[byte_pos] >> (8 - bit_left); |
| } |
| } |
| m_InPos += m_CodeLen; |
| if (code == 257) |
| break; |
| if (code < 256) { |
| if (m_OutPos == dest_size) { |
| return -5; |
| } |
| if (m_pOutput) { |
| m_pOutput[m_OutPos] = (uint8_t)code; |
| } |
| m_OutPos++; |
| last_char = (uint8_t)code; |
| if (old_code != 0xFFFFFFFF) |
| AddCode(old_code, last_char); |
| old_code = code; |
| } else if (code == 256) { |
| m_CodeLen = 9; |
| m_nCodes = 0; |
| old_code = 0xFFFFFFFF; |
| } else { |
| // Else 257 or greater. |
| if (old_code == 0xFFFFFFFF) |
| return 2; |
| |
| m_StackLen = 0; |
| if (code >= m_nCodes + 258) { |
| if (m_StackLen < sizeof(m_DecodeStack)) { |
| m_DecodeStack[m_StackLen++] = last_char; |
| } |
| DecodeString(old_code); |
| } else { |
| DecodeString(code); |
| } |
| if (m_OutPos + m_StackLen > dest_size) { |
| return -5; |
| } |
| if (m_pOutput) { |
| for (uint32_t i = 0; i < m_StackLen; i++) { |
| m_pOutput[m_OutPos + i] = m_DecodeStack[m_StackLen - i - 1]; |
| } |
| } |
| m_OutPos += m_StackLen; |
| last_char = m_DecodeStack[m_StackLen - 1]; |
| if (old_code < 256) { |
| AddCode(old_code, last_char); |
| } else if (old_code - 258 >= m_nCodes) { |
| dest_size = m_OutPos; |
| src_size = (m_InPos + 7) / 8; |
| return 0; |
| } else { |
| AddCode(old_code, last_char); |
| } |
| old_code = code; |
| } |
| } |
| dest_size = m_OutPos; |
| src_size = (m_InPos + 7) / 8; |
| return 0; |
| } |
| |
| uint8_t PathPredictor(int a, int b, int c) { |
| int p = a + b - c; |
| int pa = abs(p - a); |
| int pb = abs(p - b); |
| int pc = abs(p - c); |
| if (pa <= pb && pa <= pc) |
| return (uint8_t)a; |
| if (pb <= pc) |
| return (uint8_t)b; |
| return (uint8_t)c; |
| } |
| |
| void PNG_PredictLine(uint8_t* pDestData, |
| const uint8_t* pSrcData, |
| const uint8_t* pLastLine, |
| int bpc, |
| int nColors, |
| int nPixels) { |
| const uint32_t row_size = CalculatePitch8(bpc, nColors, nPixels).ValueOrDie(); |
| const uint32_t BytesPerPixel = (bpc * nColors + 7) / 8; |
| uint8_t tag = pSrcData[0]; |
| if (tag == 0) { |
| memmove(pDestData, pSrcData + 1, row_size); |
| return; |
| } |
| for (uint32_t byte = 0; byte < row_size; ++byte) { |
| uint8_t raw_byte = pSrcData[byte + 1]; |
| switch (tag) { |
| case 1: { |
| uint8_t left = 0; |
| if (byte >= BytesPerPixel) { |
| left = pDestData[byte - BytesPerPixel]; |
| } |
| pDestData[byte] = raw_byte + left; |
| break; |
| } |
| case 2: { |
| uint8_t up = 0; |
| if (pLastLine) { |
| up = pLastLine[byte]; |
| } |
| pDestData[byte] = raw_byte + up; |
| break; |
| } |
| case 3: { |
| uint8_t left = 0; |
| if (byte >= BytesPerPixel) { |
| left = pDestData[byte - BytesPerPixel]; |
| } |
| uint8_t up = 0; |
| if (pLastLine) { |
| up = pLastLine[byte]; |
| } |
| pDestData[byte] = raw_byte + (up + left) / 2; |
| break; |
| } |
| case 4: { |
| uint8_t left = 0; |
| if (byte >= BytesPerPixel) { |
| left = pDestData[byte - BytesPerPixel]; |
| } |
| uint8_t up = 0; |
| if (pLastLine) { |
| up = pLastLine[byte]; |
| } |
| uint8_t upper_left = 0; |
| if (byte >= BytesPerPixel && pLastLine) { |
| upper_left = pLastLine[byte - BytesPerPixel]; |
| } |
| pDestData[byte] = raw_byte + PathPredictor(left, up, upper_left); |
| break; |
| } |
| default: |
| pDestData[byte] = raw_byte; |
| break; |
| } |
| } |
| } |
| |
| bool PNG_Predictor(uint8_t*& data_buf, |
| uint32_t& data_size, |
| int Colors, |
| int BitsPerComponent, |
| int Columns) { |
| // TODO(thestig): Look into using CalculatePitch8() here. |
| const int BytesPerPixel = (Colors * BitsPerComponent + 7) / 8; |
| const int row_size = (Colors * BitsPerComponent * Columns + 7) / 8; |
| if (row_size <= 0) |
| return false; |
| const int row_count = (data_size + row_size) / (row_size + 1); |
| if (row_count <= 0) |
| return false; |
| const int last_row_size = data_size % (row_size + 1); |
| uint8_t* dest_buf = FX_Alloc2D(uint8_t, row_size, row_count); |
| uint32_t byte_cnt = 0; |
| uint8_t* pSrcData = data_buf; |
| uint8_t* pDestData = dest_buf; |
| for (int row = 0; row < row_count; row++) { |
| uint8_t tag = pSrcData[0]; |
| byte_cnt++; |
| if (tag == 0) { |
| int move_size = row_size; |
| if ((row + 1) * (move_size + 1) > (int)data_size) { |
| move_size = last_row_size - 1; |
| } |
| memmove(pDestData, pSrcData + 1, move_size); |
| pSrcData += move_size + 1; |
| pDestData += move_size; |
| byte_cnt += move_size; |
| continue; |
| } |
| for (int byte = 0; byte < row_size && byte_cnt < data_size; |
| ++byte, ++byte_cnt) { |
| uint8_t raw_byte = pSrcData[byte + 1]; |
| switch (tag) { |
| case 1: { |
| uint8_t left = 0; |
| if (byte >= BytesPerPixel) { |
| left = pDestData[byte - BytesPerPixel]; |
| } |
| pDestData[byte] = raw_byte + left; |
| break; |
| } |
| case 2: { |
| uint8_t up = 0; |
| if (row) { |
| up = pDestData[byte - row_size]; |
| } |
| pDestData[byte] = raw_byte + up; |
| break; |
| } |
| case 3: { |
| uint8_t left = 0; |
| if (byte >= BytesPerPixel) { |
| left = pDestData[byte - BytesPerPixel]; |
| } |
| uint8_t up = 0; |
| if (row) { |
| up = pDestData[byte - row_size]; |
| } |
| pDestData[byte] = raw_byte + (up + left) / 2; |
| break; |
| } |
| case 4: { |
| uint8_t left = 0; |
| if (byte >= BytesPerPixel) { |
| left = pDestData[byte - BytesPerPixel]; |
| } |
| uint8_t up = 0; |
| if (row) { |
| up = pDestData[byte - row_size]; |
| } |
| uint8_t upper_left = 0; |
| if (byte >= BytesPerPixel && row) { |
| upper_left = pDestData[byte - row_size - BytesPerPixel]; |
| } |
| pDestData[byte] = raw_byte + PathPredictor(left, up, upper_left); |
| break; |
| } |
| default: |
| pDestData[byte] = raw_byte; |
| break; |
| } |
| } |
| pSrcData += row_size + 1; |
| pDestData += row_size; |
| } |
| FX_Free(data_buf); |
| data_buf = dest_buf; |
| data_size = row_size * row_count - |
| (last_row_size > 0 ? (row_size + 1 - last_row_size) : 0); |
| return true; |
| } |
| |
| void TIFF_PredictLine(uint8_t* dest_buf, |
| uint32_t row_size, |
| int BitsPerComponent, |
| int Colors, |
| int Columns) { |
| if (BitsPerComponent == 1) { |
| int row_bits = std::min(BitsPerComponent * Colors * Columns, |
| pdfium::base::checked_cast<int>(row_size * 8)); |
| int index_pre = 0; |
| int col_pre = 0; |
| for (int i = 1; i < row_bits; i++) { |
| int col = i % 8; |
| int index = i / 8; |
| if (((dest_buf[index] >> (7 - col)) & 1) ^ |
| ((dest_buf[index_pre] >> (7 - col_pre)) & 1)) { |
| dest_buf[index] |= 1 << (7 - col); |
| } else { |
| dest_buf[index] &= ~(1 << (7 - col)); |
| } |
| index_pre = index; |
| col_pre = col; |
| } |
| return; |
| } |
| int BytesPerPixel = BitsPerComponent * Colors / 8; |
| if (BitsPerComponent == 16) { |
| for (uint32_t i = BytesPerPixel; i + 1 < row_size; i += 2) { |
| uint16_t pixel = |
| (dest_buf[i - BytesPerPixel] << 8) | dest_buf[i - BytesPerPixel + 1]; |
| pixel += (dest_buf[i] << 8) | dest_buf[i + 1]; |
| dest_buf[i] = pixel >> 8; |
| dest_buf[i + 1] = (uint8_t)pixel; |
| } |
| } else { |
| for (uint32_t i = BytesPerPixel; i < row_size; i++) { |
| dest_buf[i] += dest_buf[i - BytesPerPixel]; |
| } |
| } |
| } |
| |
| bool TIFF_Predictor(uint8_t*& data_buf, |
| uint32_t& data_size, |
| int Colors, |
| int BitsPerComponent, |
| int Columns) { |
| int row_size = (Colors * BitsPerComponent * Columns + 7) / 8; |
| if (row_size == 0) |
| return false; |
| const int row_count = (data_size + row_size - 1) / row_size; |
| const int last_row_size = data_size % row_size; |
| for (int row = 0; row < row_count; row++) { |
| uint8_t* scan_line = data_buf + row * row_size; |
| if ((row + 1) * row_size > (int)data_size) { |
| row_size = last_row_size; |
| } |
| TIFF_PredictLine(scan_line, row_size, BitsPerComponent, Colors, Columns); |
| } |
| return true; |
| } |
| |
| void FlateUncompress(pdfium::span<const uint8_t> src_buf, |
| uint32_t orig_size, |
| uint8_t*& dest_buf, |
| uint32_t& dest_size, |
| uint32_t& offset) { |
| dest_buf = nullptr; |
| dest_size = 0; |
| |
| std::unique_ptr<z_stream, FlateDeleter> context(FlateInit()); |
| if (!context) |
| return; |
| |
| FlateInput(context.get(), src_buf); |
| |
| const uint32_t kMaxInitialAllocSize = 10000000; |
| uint32_t guess_size = orig_size ? orig_size : src_buf.size() * 2; |
| guess_size = std::min(guess_size, kMaxInitialAllocSize); |
| |
| uint32_t buf_size = guess_size; |
| uint32_t last_buf_size = buf_size; |
| std::unique_ptr<uint8_t, FxFreeDeleter> guess_buf( |
| FX_Alloc(uint8_t, guess_size + 1)); |
| guess_buf.get()[guess_size] = '\0'; |
| |
| std::vector<uint8_t*> result_tmp_bufs; |
| uint8_t* cur_buf = guess_buf.release(); |
| while (1) { |
| uint32_t ret = FlateOutput(context.get(), cur_buf, buf_size); |
| uint32_t avail_buf_size = FlateGetAvailOut(context.get()); |
| if (ret != Z_OK || avail_buf_size != 0) { |
| last_buf_size = buf_size - avail_buf_size; |
| result_tmp_bufs.push_back(cur_buf); |
| break; |
| } |
| result_tmp_bufs.push_back(cur_buf); |
| cur_buf = FX_Alloc(uint8_t, buf_size + 1); |
| cur_buf[buf_size] = '\0'; |
| } |
| |
| // The TotalOut size returned from the library may not be big enough to |
| // handle the content the library returns. We can only handle items |
| // up to 4GB in size. |
| dest_size = FlateGetPossiblyTruncatedTotalOut(context.get()); |
| offset = FlateGetPossiblyTruncatedTotalIn(context.get()); |
| if (result_tmp_bufs.size() == 1) { |
| dest_buf = result_tmp_bufs[0]; |
| return; |
| } |
| |
| uint8_t* result_buf = FX_Alloc(uint8_t, dest_size); |
| uint32_t result_pos = 0; |
| uint32_t remaining = dest_size; |
| for (size_t i = 0; i < result_tmp_bufs.size(); i++) { |
| uint8_t* tmp_buf = result_tmp_bufs[i]; |
| uint32_t tmp_buf_size = buf_size; |
| if (i == result_tmp_bufs.size() - 1) |
| tmp_buf_size = last_buf_size; |
| |
| uint32_t cp_size = std::min(tmp_buf_size, remaining); |
| memcpy(result_buf + result_pos, tmp_buf, cp_size); |
| result_pos += cp_size; |
| remaining -= cp_size; |
| |
| FX_Free(result_tmp_bufs[i]); |
| } |
| dest_buf = result_buf; |
| } |
| |
| enum class PredictorType : uint8_t { kNone, kFlate, kPng }; |
| static PredictorType GetPredictor(int predictor) { |
| if (predictor >= 10) |
| return PredictorType::kPng; |
| if (predictor == 2) |
| return PredictorType::kFlate; |
| return PredictorType::kNone; |
| } |
| |
| class CCodec_FlateScanlineDecoder : public CCodec_ScanlineDecoder { |
| public: |
| CCodec_FlateScanlineDecoder(const uint8_t* src_buf, |
| uint32_t src_size, |
| int width, |
| int height, |
| int nComps, |
| int bpc); |
| ~CCodec_FlateScanlineDecoder() override; |
| |
| // CCodec_ScanlineDecoder: |
| bool v_Rewind() override; |
| uint8_t* v_GetNextLine() override; |
| uint32_t GetSrcOffset() override; |
| |
| protected: |
| std::unique_ptr<z_stream, FlateDeleter> m_pFlate; |
| pdfium::span<const uint8_t> const m_SrcBuf; |
| std::unique_ptr<uint8_t, FxFreeDeleter> const m_pScanline; |
| }; |
| |
| CCodec_FlateScanlineDecoder::CCodec_FlateScanlineDecoder(const uint8_t* src_buf, |
| uint32_t src_size, |
| int width, |
| int height, |
| int nComps, |
| int bpc) |
| : CCodec_ScanlineDecoder(width, |
| height, |
| width, |
| height, |
| nComps, |
| bpc, |
| CalculatePitch8(bpc, nComps, width).ValueOrDie()), |
| m_SrcBuf(src_buf, src_size), |
| m_pScanline(FX_Alloc(uint8_t, m_Pitch)) {} |
| |
| CCodec_FlateScanlineDecoder::~CCodec_FlateScanlineDecoder() = default; |
| |
| bool CCodec_FlateScanlineDecoder::v_Rewind() { |
| m_pFlate.reset(FlateInit()); |
| if (!m_pFlate) |
| return false; |
| |
| FlateInput(m_pFlate.get(), m_SrcBuf); |
| return true; |
| } |
| |
| uint8_t* CCodec_FlateScanlineDecoder::v_GetNextLine() { |
| FlateOutput(m_pFlate.get(), m_pScanline.get(), m_Pitch); |
| return m_pScanline.get(); |
| } |
| |
| uint32_t CCodec_FlateScanlineDecoder::GetSrcOffset() { |
| return FlateGetPossiblyTruncatedTotalIn(m_pFlate.get()); |
| } |
| |
| class CCodec_FlatePredictorScanlineDecoder final |
| : public CCodec_FlateScanlineDecoder { |
| public: |
| CCodec_FlatePredictorScanlineDecoder(const uint8_t* src_buf, |
| uint32_t src_size, |
| int width, |
| int height, |
| int comps, |
| int bpc, |
| PredictorType predictor, |
| int Colors, |
| int BitsPerComponent, |
| int Columns); |
| ~CCodec_FlatePredictorScanlineDecoder() override; |
| |
| // CCodec_ScanlineDecoder: |
| bool v_Rewind() override; |
| uint8_t* v_GetNextLine() override; |
| |
| protected: |
| void GetNextLineWithPredictedPitch(); |
| void GetNextLineWithoutPredictedPitch(); |
| |
| const PredictorType m_Predictor; |
| int m_Colors = 0; |
| int m_BitsPerComponent = 0; |
| int m_Columns = 0; |
| uint32_t m_PredictPitch = 0; |
| size_t m_LeftOver = 0; |
| uint8_t* m_pLastLine = nullptr; |
| uint8_t* m_pPredictBuffer = nullptr; |
| uint8_t* m_pPredictRaw = nullptr; |
| }; |
| |
| CCodec_FlatePredictorScanlineDecoder::CCodec_FlatePredictorScanlineDecoder( |
| const uint8_t* src_buf, |
| uint32_t src_size, |
| int width, |
| int height, |
| int comps, |
| int bpc, |
| PredictorType predictor, |
| int Colors, |
| int BitsPerComponent, |
| int Columns) |
| : CCodec_FlateScanlineDecoder(src_buf, src_size, width, height, comps, bpc), |
| m_Predictor(predictor) { |
| ASSERT(m_Predictor != PredictorType::kNone); |
| if (BitsPerComponent * Colors * Columns == 0) { |
| BitsPerComponent = m_bpc; |
| Colors = m_nComps; |
| Columns = m_OrigWidth; |
| } |
| m_Colors = Colors; |
| m_BitsPerComponent = BitsPerComponent; |
| m_Columns = Columns; |
| m_PredictPitch = |
| CalculatePitch8(m_BitsPerComponent, m_Colors, m_Columns).ValueOrDie(); |
| m_pLastLine = FX_Alloc(uint8_t, m_PredictPitch); |
| m_pPredictBuffer = FX_Alloc(uint8_t, m_PredictPitch); |
| m_pPredictRaw = FX_Alloc(uint8_t, m_PredictPitch + 1); |
| } |
| |
| CCodec_FlatePredictorScanlineDecoder::~CCodec_FlatePredictorScanlineDecoder() { |
| FX_Free(m_pLastLine); |
| FX_Free(m_pPredictBuffer); |
| FX_Free(m_pPredictRaw); |
| } |
| |
| bool CCodec_FlatePredictorScanlineDecoder::v_Rewind() { |
| if (!CCodec_FlateScanlineDecoder::v_Rewind()) |
| return false; |
| |
| m_LeftOver = 0; |
| return true; |
| } |
| |
| uint8_t* CCodec_FlatePredictorScanlineDecoder::v_GetNextLine() { |
| if (m_Pitch == m_PredictPitch) |
| GetNextLineWithPredictedPitch(); |
| else |
| GetNextLineWithoutPredictedPitch(); |
| return m_pScanline.get(); |
| } |
| |
| void CCodec_FlatePredictorScanlineDecoder::GetNextLineWithPredictedPitch() { |
| switch (m_Predictor) { |
| case PredictorType::kPng: |
| FlateOutput(m_pFlate.get(), m_pPredictRaw, m_PredictPitch + 1); |
| PNG_PredictLine(m_pScanline.get(), m_pPredictRaw, m_pLastLine, |
| m_BitsPerComponent, m_Colors, m_Columns); |
| memcpy(m_pLastLine, m_pScanline.get(), m_PredictPitch); |
| break; |
| case PredictorType::kFlate: |
| FlateOutput(m_pFlate.get(), m_pScanline.get(), m_Pitch); |
| TIFF_PredictLine(m_pScanline.get(), m_PredictPitch, m_bpc, m_nComps, |
| m_OutputWidth); |
| break; |
| default: |
| NOTREACHED(); |
| break; |
| } |
| } |
| |
| void CCodec_FlatePredictorScanlineDecoder::GetNextLineWithoutPredictedPitch() { |
| size_t bytes_to_go = m_Pitch; |
| size_t read_leftover = m_LeftOver > bytes_to_go ? bytes_to_go : m_LeftOver; |
| if (read_leftover) { |
| memcpy(m_pScanline.get(), m_pPredictBuffer + m_PredictPitch - m_LeftOver, |
| read_leftover); |
| m_LeftOver -= read_leftover; |
| bytes_to_go -= read_leftover; |
| } |
| while (bytes_to_go) { |
| switch (m_Predictor) { |
| case PredictorType::kPng: |
| FlateOutput(m_pFlate.get(), m_pPredictRaw, m_PredictPitch + 1); |
| PNG_PredictLine(m_pPredictBuffer, m_pPredictRaw, m_pLastLine, |
| m_BitsPerComponent, m_Colors, m_Columns); |
| memcpy(m_pLastLine, m_pPredictBuffer, m_PredictPitch); |
| break; |
| case PredictorType::kFlate: |
| FlateOutput(m_pFlate.get(), m_pPredictBuffer, m_PredictPitch); |
| TIFF_PredictLine(m_pPredictBuffer, m_PredictPitch, m_BitsPerComponent, |
| m_Colors, m_Columns); |
| break; |
| default: |
| NOTREACHED(); |
| break; |
| } |
| size_t read_bytes = |
| m_PredictPitch > bytes_to_go ? bytes_to_go : m_PredictPitch; |
| memcpy(m_pScanline.get() + m_Pitch - bytes_to_go, m_pPredictBuffer, |
| read_bytes); |
| m_LeftOver += m_PredictPitch - read_bytes; |
| bytes_to_go -= read_bytes; |
| } |
| } |
| |
| } // namespace |
| |
| std::unique_ptr<CCodec_ScanlineDecoder> CCodec_FlateModule::CreateDecoder( |
| const uint8_t* src_buf, |
| uint32_t src_size, |
| int width, |
| int height, |
| int nComps, |
| int bpc, |
| int predictor, |
| int Colors, |
| int BitsPerComponent, |
| int Columns) { |
| PredictorType predictor_type = GetPredictor(predictor); |
| if (predictor_type == PredictorType::kNone) { |
| return pdfium::MakeUnique<CCodec_FlateScanlineDecoder>( |
| src_buf, src_size, width, height, nComps, bpc); |
| } |
| return pdfium::MakeUnique<CCodec_FlatePredictorScanlineDecoder>( |
| src_buf, src_size, width, height, nComps, bpc, predictor_type, Colors, |
| BitsPerComponent, Columns); |
| } |
| |
| uint32_t CCodec_FlateModule::FlateOrLZWDecode(bool bLZW, |
| const uint8_t* src_buf, |
| uint32_t src_size, |
| bool bEarlyChange, |
| int predictor, |
| int Colors, |
| int BitsPerComponent, |
| int Columns, |
| uint32_t estimated_size, |
| uint8_t** dest_buf, |
| uint32_t* dest_size) { |
| *dest_buf = nullptr; |
| uint32_t offset = 0; |
| PredictorType predictor_type = GetPredictor(predictor); |
| |
| if (bLZW) { |
| auto decoder = pdfium::MakeUnique<CLZWDecoder>(); |
| *dest_size = 0xFFFFFFFF; |
| offset = src_size; |
| int err = |
| decoder->Decode(nullptr, *dest_size, src_buf, offset, bEarlyChange); |
| if (err || *dest_size == 0 || *dest_size + 1 < *dest_size) |
| return FX_INVALID_OFFSET; |
| |
| decoder = pdfium::MakeUnique<CLZWDecoder>(); |
| *dest_buf = FX_Alloc(uint8_t, *dest_size + 1); |
| (*dest_buf)[*dest_size] = '\0'; |
| decoder->Decode(*dest_buf, *dest_size, src_buf, offset, bEarlyChange); |
| } else { |
| FlateUncompress(pdfium::make_span(src_buf, src_size), estimated_size, |
| *dest_buf, *dest_size, offset); |
| } |
| |
| bool ret = false; |
| switch (predictor_type) { |
| case PredictorType::kNone: |
| return offset; |
| case PredictorType::kPng: |
| ret = PNG_Predictor(*dest_buf, *dest_size, Colors, BitsPerComponent, |
| Columns); |
| break; |
| case PredictorType::kFlate: |
| ret = TIFF_Predictor(*dest_buf, *dest_size, Colors, BitsPerComponent, |
| Columns); |
| break; |
| default: |
| NOTREACHED(); |
| break; |
| } |
| return ret ? offset : FX_INVALID_OFFSET; |
| } |
| |
| bool CCodec_FlateModule::Encode(const uint8_t* src_buf, |
| uint32_t src_size, |
| uint8_t** dest_buf, |
| uint32_t* dest_size) { |
| *dest_size = src_size + src_size / 1000 + 12; |
| *dest_buf = FX_Alloc(uint8_t, *dest_size); |
| unsigned long temp_size = *dest_size; |
| if (!FlateCompress(*dest_buf, &temp_size, src_buf, src_size)) |
| return false; |
| |
| *dest_size = (uint32_t)temp_size; |
| return true; |
| } |