xref: /aosp_15_r20/external/pdfium/fpdfsdk/cpdfsdk_customaccess.cpp (revision 3ac0a46f773bac49fa9476ec2b1cf3f8da5ec3a4)
1*3ac0a46fSAndroid Build Coastguard Worker // Copyright 2018 The PDFium Authors
2*3ac0a46fSAndroid Build Coastguard Worker // Use of this source code is governed by a BSD-style license that can be
3*3ac0a46fSAndroid Build Coastguard Worker // found in the LICENSE file.
4*3ac0a46fSAndroid Build Coastguard Worker 
5*3ac0a46fSAndroid Build Coastguard Worker // Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
6*3ac0a46fSAndroid Build Coastguard Worker 
7*3ac0a46fSAndroid Build Coastguard Worker #include "fpdfsdk/cpdfsdk_customaccess.h"
8*3ac0a46fSAndroid Build Coastguard Worker 
9*3ac0a46fSAndroid Build Coastguard Worker #include "core/fxcrt/fx_safe_types.h"
10*3ac0a46fSAndroid Build Coastguard Worker #include "third_party/base/numerics/safe_conversions.h"
11*3ac0a46fSAndroid Build Coastguard Worker 
CPDFSDK_CustomAccess(FPDF_FILEACCESS * pFileAccess)12*3ac0a46fSAndroid Build Coastguard Worker CPDFSDK_CustomAccess::CPDFSDK_CustomAccess(FPDF_FILEACCESS* pFileAccess)
13*3ac0a46fSAndroid Build Coastguard Worker     : m_FileAccess(*pFileAccess) {}
14*3ac0a46fSAndroid Build Coastguard Worker 
15*3ac0a46fSAndroid Build Coastguard Worker CPDFSDK_CustomAccess::~CPDFSDK_CustomAccess() = default;
16*3ac0a46fSAndroid Build Coastguard Worker 
GetSize()17*3ac0a46fSAndroid Build Coastguard Worker FX_FILESIZE CPDFSDK_CustomAccess::GetSize() {
18*3ac0a46fSAndroid Build Coastguard Worker   return m_FileAccess.m_FileLen;
19*3ac0a46fSAndroid Build Coastguard Worker }
20*3ac0a46fSAndroid Build Coastguard Worker 
ReadBlockAtOffset(pdfium::span<uint8_t> buffer,FX_FILESIZE offset)21*3ac0a46fSAndroid Build Coastguard Worker bool CPDFSDK_CustomAccess::ReadBlockAtOffset(pdfium::span<uint8_t> buffer,
22*3ac0a46fSAndroid Build Coastguard Worker                                              FX_FILESIZE offset) {
23*3ac0a46fSAndroid Build Coastguard Worker   if (buffer.empty() || offset < 0)
24*3ac0a46fSAndroid Build Coastguard Worker     return false;
25*3ac0a46fSAndroid Build Coastguard Worker 
26*3ac0a46fSAndroid Build Coastguard Worker   if (!pdfium::base::IsValueInRangeForNumericType<FX_FILESIZE>(buffer.size()))
27*3ac0a46fSAndroid Build Coastguard Worker     return false;
28*3ac0a46fSAndroid Build Coastguard Worker 
29*3ac0a46fSAndroid Build Coastguard Worker   FX_SAFE_FILESIZE new_pos = buffer.size();
30*3ac0a46fSAndroid Build Coastguard Worker   new_pos += offset;
31*3ac0a46fSAndroid Build Coastguard Worker   return new_pos.IsValid() && new_pos.ValueOrDie() <= GetSize() &&
32*3ac0a46fSAndroid Build Coastguard Worker          m_FileAccess.m_GetBlock(
33*3ac0a46fSAndroid Build Coastguard Worker              m_FileAccess.m_Param,
34*3ac0a46fSAndroid Build Coastguard Worker              pdfium::base::checked_cast<unsigned long>(offset), buffer.data(),
35*3ac0a46fSAndroid Build Coastguard Worker              pdfium::base::checked_cast<unsigned long>(buffer.size()));
36*3ac0a46fSAndroid Build Coastguard Worker }
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