Line data    Source code

       1             : /*
       2             :  *
       3             :  *    Copyright (c) 2020 Project CHIP Authors
       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             : #pragma once
      19             : 
      20             : #include <lib/support/BufferWriter.h>
      21             : 
      22             : #include <lib/dnssd/minimal_mdns/core/Constants.h>
      23             : #include <lib/dnssd/minimal_mdns/core/QName.h>
      24             : #include <lib/dnssd/minimal_mdns/core/RecordWriter.h>
      25             : 
      26             : namespace mdns {
      27             : namespace Minimal {
      28             : 
      29             : /// Represents a MDNS Query: QName and flags
      30             : class Query
      31             : {
      32             : public:
      33           0 :     Query(FullQName name) : mQName(name) {}
      34             : 
      35             :     bool IsAnswerViaUnicast() const { return mAnswerViaUnicast; }
      36           0 :     Query & SetAnswerViaUnicast(bool value)
      37             :     {
      38           0 :         mAnswerViaUnicast = value;
      39           0 :         return *this;
      40             :     }
      41             : 
      42             :     QType GetType() const { return mType; }
      43           0 :     Query & SetType(QType value)
      44             :     {
      45           0 :         mType = value;
      46           0 :         return *this;
      47             :     }
      48             : 
      49             :     QClass GetClass() const { return mClass; }
      50           0 :     Query & SetClass(QClass value)
      51             :     {
      52           0 :         mClass = value;
      53           0 :         return *this;
      54             :     }
      55             : 
      56             :     const FullQName & GetName() const { return mQName; }
      57             : 
      58             :     /// Append the query to the specified buffer
      59             :     ///
      60             :     /// @param hdr will be updated with a query count
      61             :     /// @param out where to write the query data
      62           0 :     bool Append(HeaderRef & hdr, RecordWriter & out) const
      63             :     {
      64             :         // Questions can only be appended before any other data is added
      65           0 :         if ((hdr.GetAdditionalCount() != 0) || (hdr.GetAnswerCount() != 0) || (hdr.GetAuthorityCount() != 0))
      66             :         {
      67           0 :             return false;
      68             :         }
      69             : 
      70           0 :         out.WriteQName(mQName)
      71           0 :             .Put16(static_cast<uint16_t>(mType))
      72           0 :             .Put16(static_cast<uint16_t>(static_cast<uint16_t>(mClass) | (mAnswerViaUnicast ? kQClassUnicastAnswerFlag : 0)));
      73             : 
      74           0 :         if (!out.Fit())
      75             :         {
      76           0 :             return false;
      77             :         }
      78             : 
      79           0 :         hdr.SetQueryCount(static_cast<uint16_t>(hdr.GetQueryCount() + 1));
      80           0 :         return true;
      81             :     }
      82             : 
      83             : private:
      84             :     const FullQName mQName;
      85             :     QType mType            = QType::ANY;
      86             :     QClass mClass          = QClass::IN;
      87             :     bool mAnswerViaUnicast = true;
      88             : };
      89             : 
      90             : } // namespace Minimal
      91             : 
      92             : } // namespace mdns