plugeth/vendor/github.com/syndtr/goleveldb/leveldb/util/util.go
Péter Szilágyi 289b30715d Godeps, vendor: convert dependency management to trash (#3198)
This commit converts the dependency management from Godeps to the vendor
folder, also switching the tool from godep to trash. Since the upstream tool
lacks a few features proposed via a few PRs, until those PRs are merged in
(if), use github.com/karalabe/trash.

You can update dependencies via trash --update.

All dependencies have been updated to their latest version.

Parts of the build system are reworked to drop old notions of Godeps and
invocation of the go vet command so that it doesn't run against the vendor
folder, as that will just blow up during vetting.

The conversion drops OpenCL (and hence GPU mining support) from ethash and our
codebase. The short reasoning is that there's noone to maintain and having
opencl libs in our deps messes up builds as go install ./... tries to build
them, failing with unsatisfied link errors for the C OpenCL deps.

golang.org/x/net/context is not vendored in. We expect it to be fetched by the
user (i.e. using go get). To keep ci.go builds reproducible the package is
"vendored" in build/_vendor.
2016-10-28 19:05:01 +02:00

74 lines
1.9 KiB
Go

// Copyright (c) 2013, Suryandaru Triandana <syndtr@gmail.com>
// All rights reserved.
//
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
// Package util provides utilities used throughout leveldb.
package util
import (
"errors"
)
var (
ErrReleased = errors.New("leveldb: resource already relesed")
ErrHasReleaser = errors.New("leveldb: releaser already defined")
)
// Releaser is the interface that wraps the basic Release method.
type Releaser interface {
// Release releases associated resources. Release should always success
// and can be called multipe times without causing error.
Release()
}
// ReleaseSetter is the interface that wraps the basic SetReleaser method.
type ReleaseSetter interface {
// SetReleaser associates the given releaser to the resources. The
// releaser will be called once coresponding resources released.
// Calling SetReleaser with nil will clear the releaser.
//
// This will panic if a releaser already present or coresponding
// resource is already released. Releaser should be cleared first
// before assigned a new one.
SetReleaser(releaser Releaser)
}
// BasicReleaser provides basic implementation of Releaser and ReleaseSetter.
type BasicReleaser struct {
releaser Releaser
released bool
}
// Released returns whether Release method already called.
func (r *BasicReleaser) Released() bool {
return r.released
}
// Release implements Releaser.Release.
func (r *BasicReleaser) Release() {
if !r.released {
if r.releaser != nil {
r.releaser.Release()
r.releaser = nil
}
r.released = true
}
}
// SetReleaser implements ReleaseSetter.SetReleaser.
func (r *BasicReleaser) SetReleaser(releaser Releaser) {
if r.released {
panic(ErrReleased)
}
if r.releaser != nil && releaser != nil {
panic(ErrHasReleaser)
}
r.releaser = releaser
}
type NoopReleaser struct{}
func (NoopReleaser) Release() {}