1 // Copyright 2017 PDFium Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 // Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com 6 7 #include "core/fxcrt/cfx_binarybuf.h" 8 9 #include <algorithm> 10 #include <utility> 11 12 CFX_BinaryBuf::CFX_BinaryBuf() 13 : m_AllocStep(0), m_AllocSize(0), m_DataSize(0) {} 14 15 CFX_BinaryBuf::~CFX_BinaryBuf() {} 16 17 void CFX_BinaryBuf::Delete(size_t start_index, size_t count) { 18 if (!m_pBuffer || count > m_DataSize || start_index > m_DataSize - count) 19 return; 20 21 memmove(m_pBuffer.get() + start_index, m_pBuffer.get() + start_index + count, 22 m_DataSize - start_index - count); 23 m_DataSize -= count; 24 } 25 26 size_t CFX_BinaryBuf::GetLength() const { 27 return m_DataSize; 28 } 29 30 void CFX_BinaryBuf::Clear() { 31 m_DataSize = 0; 32 } 33 34 std::unique_ptr<uint8_t, FxFreeDeleter> CFX_BinaryBuf::DetachBuffer() { 35 m_DataSize = 0; 36 m_AllocSize = 0; 37 return std::move(m_pBuffer); 38 } 39 40 void CFX_BinaryBuf::EstimateSize(size_t size, size_t step) { 41 m_AllocStep = step; 42 if (m_AllocSize < size) 43 ExpandBuf(size - m_DataSize); 44 } 45 46 void CFX_BinaryBuf::ExpandBuf(size_t add_size) { 47 FX_SAFE_SIZE_T new_size = m_DataSize; 48 new_size += add_size; 49 if (m_AllocSize >= new_size.ValueOrDie()) 50 return; 51 52 size_t alloc_step = std::max(static_cast<size_t>(128), 53 m_AllocStep ? m_AllocStep : m_AllocSize / 4); 54 new_size += alloc_step - 1; // Quantize, don't combine these lines. 55 new_size /= alloc_step; 56 new_size *= alloc_step; 57 m_AllocSize = new_size.ValueOrDie(); 58 m_pBuffer.reset(m_pBuffer 59 ? FX_Realloc(uint8_t, m_pBuffer.release(), m_AllocSize) 60 : FX_Alloc(uint8_t, m_AllocSize)); 61 } 62 63 void CFX_BinaryBuf::AppendBlock(const void* pBuf, size_t size) { 64 if (size == 0) 65 return; 66 67 ExpandBuf(size); 68 if (pBuf) { 69 memcpy(m_pBuffer.get() + m_DataSize, pBuf, size); 70 } else { 71 memset(m_pBuffer.get() + m_DataSize, 0, size); 72 } 73 m_DataSize += size; 74 } 75