github.com/ethereum/go-ethereum@v1.14.3/miner/pending.go (about)

     1  // Copyright 2024 The go-ethereum Authors
     2  // This file is part of the go-ethereum library.
     3  //
     4  // The go-ethereum library is free software: you can redistribute it and/or modify
     5  // it under the terms of the GNU Lesser General Public License as published by
     6  // the Free Software Foundation, either version 3 of the License, or
     7  // (at your option) any later version.
     8  //
     9  // The go-ethereum library is distributed in the hope that it will be useful,
    10  // but WITHOUT ANY WARRANTY; without even the implied warranty of
    11  // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
    12  // GNU Lesser General Public License for more details.
    13  //
    14  // You should have received a copy of the GNU Lesser General Public License
    15  // along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
    16  
    17  package miner
    18  
    19  import (
    20  	"sync"
    21  	"time"
    22  
    23  	"github.com/ethereum/go-ethereum/common"
    24  )
    25  
    26  // pendingTTL indicates the period of time a generated pending block should
    27  // exist to serve RPC requests before being discarded if the parent block
    28  // has not changed yet. The value is chosen to align with the recommit interval.
    29  const pendingTTL = 2 * time.Second
    30  
    31  // pending wraps a pending block with additional metadata.
    32  type pending struct {
    33  	created    time.Time
    34  	parentHash common.Hash
    35  	result     *newPayloadResult
    36  	lock       sync.Mutex
    37  }
    38  
    39  // resolve retrieves the cached pending result if it's available. Nothing will be
    40  // returned if the parentHash is not matched or the result is already too old.
    41  //
    42  // Note, don't modify the returned payload result.
    43  func (p *pending) resolve(parentHash common.Hash) *newPayloadResult {
    44  	p.lock.Lock()
    45  	defer p.lock.Unlock()
    46  
    47  	if p.result == nil {
    48  		return nil
    49  	}
    50  	if parentHash != p.parentHash {
    51  		return nil
    52  	}
    53  	if time.Since(p.created) > pendingTTL {
    54  		return nil
    55  	}
    56  	return p.result
    57  }
    58  
    59  // update refreshes the cached pending block with newly created one.
    60  func (p *pending) update(parent common.Hash, result *newPayloadResult) {
    61  	p.lock.Lock()
    62  	defer p.lock.Unlock()
    63  
    64  	p.parentHash = parent
    65  	p.result = result
    66  	p.created = time.Now()
    67  }