Line data    Source code

       1              : /*
       2              :  *
       3              :  *    Copyright (c) 2021 Project CHIP Authors
       4              :  *    All rights reserved.
       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              : #pragma once
      20              : 
      21              : #include "lib/core/TLV.h"
      22              : #include "system/SystemPacketBuffer.h"
      23              : #include "system/TLVPacketBufferBackingStore.h"
      24              : #include <app/AppConfig.h>
      25              : #include <app/AttributePathParams.h>
      26              : #include <app/ReadClient.h>
      27              : #include <vector>
      28              : 
      29              : #if CHIP_CONFIG_ENABLE_READ_CLIENT
      30              : namespace chip {
      31              : namespace app {
      32              : 
      33              : /*
      34              :  * This is an adapter that intercepts calls that deliver data from the ReadClient,
      35              :  * selectively buffers up list chunks in TLV and reconstitutes them into a singular, contiguous TLV array
      36              :  * upon completion of delivery of all chunks. This is then delivered to a compliant ReadClient::Callback
      37              :  * without any awareness on their part that chunking happened.
      38              :  *
      39              :  */
      40              : class BufferedReadCallback : public ReadClient::Callback
      41              : {
      42              : public:
      43          836 :     BufferedReadCallback(Callback & callback, bool allowLargePayload = false) :
      44          836 :         mAllowLargePayload(allowLargePayload), mCallback(callback)
      45          836 :     {}
      46              : 
      47              : private:
      48              :     /*
      49              :      * Generates the reconsistuted TLV array from the stored individual list elements
      50              :      */
      51              :     CHIP_ERROR GenerateListTLV(TLV::ScopedBufferTLVReader & reader);
      52              : 
      53              :     /*
      54              :      * Dispatch any buffered list data if we need to. Buffered data will only be dispatched if:
      55              :      *  1. The path provided in aPath is different from the buffered path being tracked internally AND the type of data
      56              :      *     in the buffer is list data
      57              :      *
      58              :      *     OR
      59              :      *
      60              :      *  2. The path provided in aPath is similar to what is buffered but we've hit the end of the report.
      61              :      *
      62              :      */
      63              :     CHIP_ERROR DispatchBufferedData(const ConcreteAttributePath & aPath, const StatusIB & aStatus, bool aEndOfReport = false);
      64              : 
      65              :     /*
      66              :      * Buffer up list data as they arrive.
      67              :      */
      68              :     CHIP_ERROR BufferData(const ConcreteDataAttributePath & aPath, TLV::TLVReader * apReader);
      69              : 
      70              :     //
      71              :     // ReadClient::Callback
      72              :     //
      73              :     void OnReportBegin() override;
      74              :     void OnReportEnd() override;
      75              :     void OnAttributeData(const ConcreteDataAttributePath & aPath, TLV::TLVReader * apData, const StatusIB & aStatus) override;
      76           98 :     void OnError(CHIP_ERROR aError) override
      77              :     {
      78           98 :         mBufferedList.clear();
      79           98 :         return mCallback.OnError(aError);
      80              :     }
      81              : 
      82         1532 :     void OnEventData(const EventHeader & aEventHeader, TLV::TLVReader * apData, const StatusIB * apStatus) override
      83              :     {
      84         1532 :         return mCallback.OnEventData(aEventHeader, apData, apStatus);
      85              :     }
      86              : 
      87          822 :     void OnDone(ReadClient * apReadClient) override { return mCallback.OnDone(apReadClient); }
      88          207 :     void OnSubscriptionEstablished(SubscriptionId aSubscriptionId) override
      89              :     {
      90          207 :         mCallback.OnSubscriptionEstablished(aSubscriptionId);
      91          207 :     }
      92              : 
      93            6 :     CHIP_ERROR OnResubscriptionNeeded(ReadClient * apReadClient, CHIP_ERROR aTerminationCause) override
      94              :     {
      95            6 :         return mCallback.OnResubscriptionNeeded(apReadClient, aTerminationCause);
      96              :     }
      97              : 
      98          208 :     void OnDeallocatePaths(chip::app::ReadPrepareParams && aReadPrepareParams) override
      99              :     {
     100          208 :         return mCallback.OnDeallocatePaths(std::move(aReadPrepareParams));
     101              :     }
     102              : 
     103         1253 :     virtual CHIP_ERROR OnUpdateDataVersionFilterList(DataVersionFilterIBs::Builder & aDataVersionFilterIBsBuilder,
     104              :                                                      const Span<AttributePathParams> & aAttributePaths,
     105              :                                                      bool & aEncodedDataVersionList) override
     106              :     {
     107         1253 :         return mCallback.OnUpdateDataVersionFilterList(aDataVersionFilterIBsBuilder, aAttributePaths, aEncodedDataVersionList);
     108              :     }
     109              : 
     110            4 :     virtual CHIP_ERROR GetHighestReceivedEventNumber(Optional<EventNumber> & aEventNumber) override
     111              :     {
     112            4 :         return mCallback.GetHighestReceivedEventNumber(aEventNumber);
     113              :     }
     114              : 
     115            9 :     void OnUnsolicitedMessageFromPublisher(ReadClient * apReadClient) override
     116              :     {
     117            9 :         return mCallback.OnUnsolicitedMessageFromPublisher(apReadClient);
     118              :     }
     119              : 
     120            0 :     void OnCASESessionEstablished(const SessionHandle & aSession, ReadPrepareParams & aSubscriptionParams) override
     121              :     {
     122            0 :         return mCallback.OnCASESessionEstablished(aSession, aSubscriptionParams);
     123              :     }
     124              : 
     125              :     /*
     126              :      * Given a reader positioned at a list element, allocate a packet buffer, copy the list item where
     127              :      * the reader is positioned into that buffer and add it to our buffered list for tracking.
     128              :      *
     129              :      * This should be called in list index order starting from the lowest index that needs to be buffered.
     130              :      *
     131              :      */
     132              :     CHIP_ERROR BufferListItem(TLV::TLVReader & reader);
     133              :     ConcreteDataAttributePath mBufferedPath;
     134              :     std::vector<System::PacketBufferHandle> mBufferedList;
     135              :     bool mAllowLargePayload = false;
     136              :     Callback & mCallback;
     137              : };
     138              : 
     139              : } // namespace app
     140              : } // namespace chip
     141              : #endif // CHIP_CONFIG_ENABLE_READ_CLIENT