github.com/uber/kraken@v0.1.4/lib/torrent/scheduler/dispatch/piecerequest/policy.go (about)

     1  // Copyright (c) 2016-2019 Uber Technologies, Inc.
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //     http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  package piecerequest
    15  
    16  import (
    17  	"github.com/uber/kraken/utils/syncutil"
    18  
    19  	"github.com/willf/bitset"
    20  )
    21  
    22  // pieceSelectionPolicy defines a policy for determining which pieces to request
    23  // given a set of candidates and relevant stats about them.
    24  // If 'valid' is not thread-safe, caller must handle locking.
    25  type pieceSelectionPolicy interface {
    26  	selectPieces(
    27  		limit int,
    28  		valid func(int) bool, // whether the given piece is a valid selection or not
    29  		candidates *bitset.BitSet,
    30  		numPeersByPiece syncutil.Counters) ([]int, error)
    31  }