| // Copyright 2018 The PDFium Authors |
| // 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 "fpdfsdk/cpdfsdk_customaccess.h" |
| |
| #include "core/fxcrt/fx_safe_types.h" |
| #include "core/fxcrt/numerics/safe_conversions.h" |
| |
| CPDFSDK_CustomAccess::CPDFSDK_CustomAccess(FPDF_FILEACCESS* pFileAccess) |
| : m_FileAccess(*pFileAccess) {} |
| |
| CPDFSDK_CustomAccess::~CPDFSDK_CustomAccess() = default; |
| |
| FX_FILESIZE CPDFSDK_CustomAccess::GetSize() { |
| return m_FileAccess.m_FileLen; |
| } |
| |
| bool CPDFSDK_CustomAccess::ReadBlockAtOffset(pdfium::span<uint8_t> buffer, |
| FX_FILESIZE offset) { |
| if (buffer.empty() || offset < 0) |
| return false; |
| |
| if (!pdfium::IsValueInRangeForNumericType<FX_FILESIZE>(buffer.size())) { |
| return false; |
| } |
| |
| FX_SAFE_FILESIZE new_pos = buffer.size(); |
| new_pos += offset; |
| return new_pos.IsValid() && new_pos.ValueOrDie() <= GetSize() && |
| m_FileAccess.m_GetBlock( |
| m_FileAccess.m_Param, pdfium::checked_cast<unsigned long>(offset), |
| buffer.data(), pdfium::checked_cast<unsigned long>(buffer.size())); |
| } |