Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 3a319de5 authored by Hansong Zhang's avatar Hansong Zhang
Browse files

Introduce MultiPriorityQueue 

ACL and L2cap needs to prioritize some link/channels in some cases.  A
traditional priority queue requires predefined comparison, which can be
hard for our use case (PacketBuilder).  Instead, we specify the priority
value when we push to a queue.

Test: bluetooth_test_gd
Tag: #gd-refactor
Bug: 141555841
Change-Id: I33414b4bf81e9f63c88d8627376b565f5c5bb6de
parent 43ebd8c8

system/gd/common/Android.bp

+1 −0
Original line number Diff line number Diff line
@@ -17,6 +17,7 @@ filegroup { 
        "init_flags_test.cc",

        "list_map_test.cc",

        "lru_cache_test.cc",

        "multi_priority_queue_test.cc",

        "numbers_test.cc",

        "strings_test.cc",

    ],

system/gd/common/multi_priority_queue.h

0 → 100644
+69 −0
Original line number Diff line number Diff line 
/******************************************************************************

 *

 *  Copyright 2021 The Android Open Source Project

 *

 *  Licensed under the Apache License, Version 2.0 (the "License");

 *  you may not use this file except in compliance with the License.

 *  You may obtain a copy of the License at:

 *

 *  http://www.apache.org/licenses/LICENSE-2.0

 *

 *  Unless required by applicable law or agreed to in writing, software

 *  distributed under the License is distributed on an "AS IS" BASIS,

 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

 *  See the License for the specific language governing permissions and

 *  limitations under the License.

 *

 ******************************************************************************/



#pragma once



#include <array>

#include <queue>



namespace bluetooth {

namespace common {



/**

 * A queue implementation which supports items with multiple priorities.

 * Items with greater priority value will be dequeued first.

 * When Enqueuing, the user can specify the priority (0 by default).

 * This can be used by ACL or L2CAP lower queue end sender to prioritize some link or channel, used by A2DP.

 */

template <typename T, int NUM_PRIORITY_LEVELS = 2>

class MultiPriorityQueue {

  static_assert(NUM_PRIORITY_LEVELS > 1);



 public:

  // Get the front item with the highest priority.  Queue must be non-empty.

  T& front() {

    return queues_[next_to_dequeue_.top()].front();

  }



  [[nodiscard]] bool empty() const {

    return next_to_dequeue_.empty();

  }



  [[nodiscard]] size_t size() const {

    return next_to_dequeue_.size();

  }



  // Push the item with specified priority

  void push(const T& t, int priority = 0) {

    queues_[priority].push(t);

    next_to_dequeue_.push(priority);

  }



  // Pop the item in the front

  void pop() {

    queues_[next_to_dequeue_.top()].pop();

    next_to_dequeue_.pop();

  }



 private:

  std::array<std::queue<T>, NUM_PRIORITY_LEVELS> queues_;

  std::priority_queue<int> next_to_dequeue_;

};



}  // namespace common

}  // namespace bluetooth

system/gd/common/multi_priority_queue_test.cc

0 → 100644
+63 −0
Original line number Diff line number Diff line 
/******************************************************************************

 *

 *  Copyright 2021 The Android Open Source Project

 *

 *  Licensed under the Apache License, Version 2.0 (the "License");

 *  you may not use this file except in compliance with the License.

 *  You may obtain a copy of the License at:

 *

 *  http://www.apache.org/licenses/LICENSE-2.0

 *

 *  Unless required by applicable law or agreed to in writing, software

 *  distributed under the License is distributed on an "AS IS" BASIS,

 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

 *  See the License for the specific language governing permissions and

 *  limitations under the License.

 *

 ******************************************************************************/



#include <gtest/gtest.h>



#include "common/multi_priority_queue.h"



namespace bluetooth {

namespace common {



TEST(MultiPriorityQueueTest, without_high_priority_item) {

  common::MultiPriorityQueue<int, 2> q;

  EXPECT_TRUE(q.empty());

  q.push(0);

  q.push(1, 0);

  q.push(2);

  EXPECT_EQ(q.size(), 3);

  for (int i = 0; i < 3; i++) {

    EXPECT_EQ(q.front(), i);

    q.pop();

  }

  EXPECT_TRUE(q.empty());

}



TEST(MultiPriorityQueueTest, with_high_priority_item) {

  common::MultiPriorityQueue<int, 2> q;

  q.push(1);

  q.push(2);

  q.push(0, 1);

  for (int i = 0; i < 3; i++) {

    EXPECT_EQ(q.front(), i);

    q.pop();

  }

}



TEST(MultiPriorityQueueTest, with_multiple_priority_item) {

  common::MultiPriorityQueue<int, 3> q;

  q.push(1, 1);

  q.push(0, 2);

  q.push(2, 0);

  for (int i = 0; i < 3; i++) {

    EXPECT_EQ(q.front(), i);

    q.pop();

  }

}



}  // namespace common

}  // namespace bluetooth