Line data    Source code

       1              : /*
       2              :  *
       3              :  *    Copyright (c) 2021 Project CHIP Authors
       4              :  *    Copyright (c) 2013-2017 Nest Labs, Inc.
       5              :  *
       6              :  *    Licensed under the Apache License, Version 2.0 (the "License");
       7              :  *    you may not use this file except in compliance with the License.
       8              :  *    You may obtain a copy of the License at
       9              :  *
      10              :  *        http://www.apache.org/licenses/LICENSE-2.0
      11              :  *
      12              :  *    Unless required by applicable law or agreed to in writing, software
      13              :  *    distributed under the License is distributed on an "AS IS" BASIS,
      14              :  *    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
      15              :  *    See the License for the specific language governing permissions and
      16              :  *    limitations under the License.
      17              :  */
      18              : 
      19              : /**
      20              :  *    @file
      21              :  *      This file contains an implementation of TLVBackingStore using PacketBuffers.
      22              :  */
      23              : 
      24              : #include <system/TLVPacketBufferBackingStore.h>
      25              : 
      26              : #include <lib/support/SafeInt.h>
      27              : 
      28              : namespace chip {
      29              : namespace System {
      30              : 
      31           96 : CHIP_ERROR TLVPacketBufferBackingStore::OnInit(chip::TLV::TLVReader & reader, const uint8_t *& bufStart, uint32_t & bufLen)
      32              : {
      33           96 :     bufStart = mHeadBuffer->Start();
      34           96 :     VerifyOrReturnError(CanCastTo<uint32_t>(mHeadBuffer->DataLength()), CHIP_ERROR_INVALID_ARGUMENT);
      35           96 :     bufLen = static_cast<uint32_t>(mHeadBuffer->DataLength());
      36           96 :     return CHIP_NO_ERROR;
      37              : }
      38              : 
      39            0 : CHIP_ERROR TLVPacketBufferBackingStore::GetNextBuffer(chip::TLV::TLVReader & reader, const uint8_t *& bufStart, uint32_t & bufLen)
      40              : {
      41            0 :     if (mUseChainedBuffers)
      42              :     {
      43            0 :         mCurrentBuffer.Advance();
      44              :     }
      45              :     else
      46              :     {
      47            0 :         mCurrentBuffer = nullptr;
      48              :     }
      49              : 
      50            0 :     if (mCurrentBuffer.IsNull())
      51              :     {
      52            0 :         bufStart = nullptr;
      53            0 :         bufLen   = 0;
      54              :     }
      55              :     else
      56              :     {
      57            0 :         bufStart = mCurrentBuffer->Start();
      58            0 :         VerifyOrReturnError(CanCastTo<uint32_t>(mCurrentBuffer->DataLength()), CHIP_ERROR_INVALID_ARGUMENT);
      59            0 :         bufLen = static_cast<uint32_t>(mCurrentBuffer->DataLength());
      60              :     }
      61              : 
      62            0 :     return CHIP_NO_ERROR;
      63              : }
      64              : 
      65        19194 : CHIP_ERROR TLVPacketBufferBackingStore::OnInit(chip::TLV::TLVWriter & writer, uint8_t *& bufStart, uint32_t & bufLen)
      66              : {
      67        19194 :     bufStart = mHeadBuffer->Start() + mHeadBuffer->DataLength();
      68        19194 :     VerifyOrReturnError(CanCastTo<uint32_t>(mHeadBuffer->AvailableDataLength()), CHIP_ERROR_INVALID_ARGUMENT);
      69        19194 :     bufLen = static_cast<uint32_t>(mHeadBuffer->AvailableDataLength());
      70        19194 :     return CHIP_NO_ERROR;
      71              : }
      72              : 
      73        23252 : CHIP_ERROR TLVPacketBufferBackingStore::FinalizeBuffer(chip::TLV::TLVWriter & writer, uint8_t * bufStart, uint32_t dataLen)
      74              : {
      75        23252 :     uint8_t * endPtr = bufStart + dataLen;
      76              : 
      77        23252 :     intptr_t length = endPtr - mCurrentBuffer->Start();
      78        23252 :     if (!CanCastTo<uint32_t>(length))
      79              :     {
      80            0 :         return CHIP_ERROR_INVALID_ARGUMENT;
      81              :     }
      82        23252 :     mCurrentBuffer->SetDataLength(static_cast<uint32_t>(length), mHeadBuffer);
      83              : 
      84        23252 :     return CHIP_NO_ERROR;
      85              : }
      86              : 
      87         2591 : CHIP_ERROR TLVPacketBufferBackingStore::GetNewBuffer(chip::TLV::TLVWriter & writer, uint8_t *& bufStart, uint32_t & bufLen)
      88              : {
      89         2591 :     if (!mUseChainedBuffers)
      90              :     {
      91         2209 :         return CHIP_ERROR_NO_MEMORY;
      92              :     }
      93              : 
      94          382 :     mCurrentBuffer.Advance();
      95          382 :     if (mCurrentBuffer.IsNull())
      96              :     {
      97          382 :         mCurrentBuffer = PacketBufferHandle::New(System::PacketBuffer::kMaxSizeWithoutReserve, 0);
      98          382 :         if (mCurrentBuffer.IsNull())
      99              :         {
     100            0 :             return CHIP_ERROR_NO_MEMORY;
     101              :         }
     102          382 :         mHeadBuffer->AddToEnd(mCurrentBuffer.Retain());
     103              :     }
     104              : 
     105          382 :     if (mCurrentBuffer.IsNull())
     106              :     {
     107            0 :         bufStart = nullptr;
     108            0 :         bufLen   = 0;
     109              :     }
     110              :     else
     111              :     {
     112          382 :         bufStart = mCurrentBuffer->Start();
     113          382 :         VerifyOrReturnError(CanCastTo<uint32_t>(mCurrentBuffer->MaxDataLength()), CHIP_ERROR_INVALID_ARGUMENT);
     114          382 :         bufLen = static_cast<uint32_t>(mCurrentBuffer->MaxDataLength());
     115              :     }
     116              : 
     117          382 :     return CHIP_NO_ERROR;
     118              : }
     119              : 
     120              : } // namespace System
     121              : } // namespace chip