Line data    Source code

       1              : /*
       2              :  *    Copyright (c) 2024 Project CHIP Authors
       3              :  *    All rights reserved.
       4              :  *
       5              :  *    Licensed under the Apache License, Version 2.0 (the "License");
       6              :  *    you may not use this file except in compliance with the License.
       7              :  *    You may obtain a copy of the License at
       8              :  *
       9              :  *        http://www.apache.org/licenses/LICENSE-2.0
      10              :  *
      11              :  *    Unless required by applicable law or agreed to in writing, software
      12              :  *    distributed under the License is distributed on an "AS IS" BASIS,
      13              :  *    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
      14              :  *    See the License for the specific language governing permissions and
      15              :  *    limitations under the License.
      16              :  */
      17              : 
      18              : #include "FabricScopedPreEncodedValue.h"
      19              : #include <lib/core/TLVReader.h>
      20              : #include <lib/support/CodeUtils.h>
      21              : 
      22              : #include <optional>
      23              : 
      24              : namespace chip {
      25              : namespace app {
      26              : namespace DataModel {
      27              : 
      28            4 : FabricScopedPreEncodedValue::FabricScopedPreEncodedValue(const ByteSpan & aData) : mData(aData) {}
      29              : 
      30            3 : CHIP_ERROR FabricScopedPreEncodedValue::EncodeForRead(TLV::TLVWriter & aWriter, TLV::Tag aTag, FabricIndex aFabricIndex) const
      31              : {
      32            3 :     TLV::TLVReader reader;
      33            3 :     reader.Init(mData);
      34              : 
      35            3 :     ReturnErrorOnFailure(reader.Next());
      36              : 
      37            3 :     return aWriter.CopyElement(aTag, reader);
      38              : }
      39              : 
      40            6 : FabricIndex FabricScopedPreEncodedValue::GetFabricIndex() const
      41              : {
      42            6 :     TLV::TLVReader reader;
      43            6 :     reader.Init(mData);
      44            6 :     CHIP_ERROR err = reader.Next();
      45            6 :     if (err != CHIP_NO_ERROR)
      46              :     {
      47            0 :         return kUndefinedFabricIndex;
      48              :     }
      49              : 
      50              :     // We must have a struct here.
      51            6 :     if (reader.GetType() != TLV::kTLVType_Structure)
      52              :     {
      53            0 :         return kUndefinedFabricIndex;
      54              :     }
      55              : 
      56              :     TLV::TLVType structType;
      57            6 :     err = reader.EnterContainer(structType);
      58            6 :     if (err != CHIP_NO_ERROR)
      59              :     {
      60            0 :         return kUndefinedFabricIndex;
      61              :     }
      62              : 
      63              :     // Now look for a single field with the right tag.
      64            6 :     std::optional<FabricIndex> foundFabricIndex;
      65            6 :     constexpr TLV::Tag kFabricIndexTag = TLV::ContextTag(254);
      66           18 :     while ((err = reader.Next()) == CHIP_NO_ERROR)
      67              :     {
      68           12 :         if (reader.GetTag() != kFabricIndexTag)
      69              :         {
      70            6 :             continue;
      71              :         }
      72              : 
      73            6 :         if (foundFabricIndex.has_value())
      74              :         {
      75              :             // Two fabric indices?  Just give up.  Note that this will lead to
      76              :             // errors encoding our value.
      77            0 :             return kUndefinedFabricIndex;
      78              :         }
      79              : 
      80            6 :         err = reader.Get(foundFabricIndex.emplace());
      81            6 :         if (err != CHIP_NO_ERROR)
      82              :         {
      83            0 :             return kUndefinedFabricIndex;
      84              :         }
      85              :     }
      86              : 
      87            6 :     if (err != CHIP_ERROR_END_OF_TLV)
      88              :     {
      89            0 :         return kUndefinedFabricIndex;
      90              :     }
      91              : 
      92            6 :     err = reader.ExitContainer(structType);
      93            6 :     if (err != CHIP_NO_ERROR)
      94              :     {
      95            0 :         return kUndefinedFabricIndex;
      96              :     }
      97              : 
      98            6 :     return foundFabricIndex.value_or(kUndefinedFabricIndex);
      99              : }
     100              : 
     101              : } // namespace DataModel
     102              : } // namespace app
     103              : } // namespace chip