github.com/bcskill/bcschain/v3@v3.4.9-beta2/internal/ethapi/addrlock.go (about)

     1  // Copyright 2017 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 ethapi
    18  
    19  import (
    20  	"sync"
    21  
    22  	"github.com/bcskill/bcschain/v3/common"
    23  )
    24  
    25  // AddrLocker stores locks per account. This is used to prevent another tx getting the
    26  // same nonce, by holding the lock when signing a transaction.
    27  type AddrLocker struct {
    28  	mu    sync.RWMutex
    29  	locks map[common.Address]*sync.Mutex
    30  }
    31  
    32  func newAddrLocker() *AddrLocker {
    33  	return &AddrLocker{
    34  		locks: make(map[common.Address]*sync.Mutex),
    35  	}
    36  }
    37  
    38  // lock returns the lock of the given address.
    39  func (l *AddrLocker) lock(address common.Address) sync.Locker {
    40  	l.mu.RLock()
    41  	mu, ok := l.locks[address]
    42  	l.mu.RUnlock()
    43  	if ok {
    44  		return mu
    45  	}
    46  	l.mu.Lock()
    47  	mu, ok = l.locks[address]
    48  	if !ok {
    49  		mu = new(sync.Mutex)
    50  		l.locks[address] = mu
    51  	}
    52  	l.mu.Unlock()
    53  	return mu
    54  }