plugeth/accounts/watch.go
Felix Lange a9f26dcd0d accounts: cache key addresses
In order to avoid disk thrashing for Accounts and HasAccount,
address->key file mappings are now cached in memory. This makes it no
longer necessary to keep the key address in the file name. The address
of each key is derived from file content instead.

There are minor user-visible changes:

- "geth account list" now reports key file paths alongside the address.
- If multiple keys are present for an address, unlocking by address is
  not possible. Users are directed to remove the duplicate files
  instead. Unlocking by index is still possible.
- Key files are overwritten written in place when updating the password.
2016-04-12 15:58:07 +02:00

114 lines
2.7 KiB
Go

// Copyright 2016 The go-ethereum Authors
// This file is part of the go-ethereum library.
//
// The go-ethereum library is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// The go-ethereum library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
// +build darwin freebsd linux netbsd solaris windows
package accounts
import (
"time"
"github.com/ethereum/go-ethereum/logger"
"github.com/ethereum/go-ethereum/logger/glog"
"github.com/rjeczalik/notify"
)
type watcher struct {
ac *addrCache
starting bool
running bool
ev chan notify.EventInfo
quit chan struct{}
}
func newWatcher(ac *addrCache) *watcher {
return &watcher{
ac: ac,
ev: make(chan notify.EventInfo, 10),
quit: make(chan struct{}),
}
}
// starts the watcher loop in the background.
// Start a watcher in the background if that's not already in progress.
// The caller must hold w.ac.mu.
func (w *watcher) start() {
if w.starting || w.running {
return
}
w.starting = true
go w.loop()
}
func (w *watcher) close() {
close(w.quit)
}
func (w *watcher) loop() {
defer func() {
w.ac.mu.Lock()
w.running = false
w.starting = false
w.ac.mu.Unlock()
}()
err := notify.Watch(w.ac.keydir, w.ev, notify.All)
if err != nil {
glog.V(logger.Detail).Infof("can't watch %s: %v", w.ac.keydir, err)
return
}
defer notify.Stop(w.ev)
glog.V(logger.Detail).Infof("now watching %s", w.ac.keydir)
defer glog.V(logger.Detail).Infof("no longer watching %s", w.ac.keydir)
w.ac.mu.Lock()
w.running = true
w.ac.mu.Unlock()
// Wait for file system events and reload.
// When an event occurs, the reload call is delayed a bit so that
// multiple events arriving quickly only cause a single reload.
var (
debounce = time.NewTimer(0)
debounceDuration = 500 * time.Millisecond
inCycle, hadEvent bool
)
defer debounce.Stop()
for {
select {
case <-w.quit:
return
case <-w.ev:
if !inCycle {
debounce.Reset(debounceDuration)
inCycle = true
} else {
hadEvent = true
}
case <-debounce.C:
w.ac.mu.Lock()
w.ac.reload()
w.ac.mu.Unlock()
if hadEvent {
debounce.Reset(debounceDuration)
inCycle, hadEvent = true, false
} else {
inCycle, hadEvent = false, false
}
}
}
}