switch to go vendoring

vendor/github.com/gofrs/flock/.gitignore

@@ -0,0 +1,24 @@
+# Compiled Object files, Static and Dynamic libs (Shared Objects)
+*.o
+*.a
+*.so
+
+# Folders
+_obj
+_test
+
+# Architecture specific extensions/prefixes
+*.[568vq]
+[568vq].out
+
+*.cgo1.go
+*.cgo2.c
+_cgo_defun.c
+_cgo_gotypes.go
+_cgo_export.*
+
+_testmain.go
+
+*.exe
+*.test
+*.prof

vendor/github.com/gofrs/flock/.travis.yml

@@ -0,0 +1,10 @@
+language: go
+go:
+  - 1.14.x
+  - 1.15.x
+script: go test -v -check.vv -race ./...
+sudo: false
+notifications:
+  email:
+    on_success: never
+    on_failure: always

vendor/github.com/gofrs/flock/LICENSE

@@ -0,0 +1,27 @@
+Copyright (c) 2015-2020, Tim Heckman
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:
+
+* Redistributions of source code must retain the above copyright notice, this
+  list of conditions and the following disclaimer.
+
+* Redistributions in binary form must reproduce the above copyright notice,
+  this list of conditions and the following disclaimer in the documentation
+  and/or other materials provided with the distribution.
+
+* Neither the name of gofrs nor the names of its contributors may be used
+  to endorse or promote products derived from this software without
+  specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

vendor/github.com/gofrs/flock/README.md

@@ -0,0 +1,41 @@
+# flock
+[![TravisCI Build Status](https://img.shields.io/travis/gofrs/flock/master.svg?style=flat)](https://travis-ci.org/gofrs/flock)
+[![GoDoc](https://img.shields.io/badge/godoc-flock-blue.svg?style=flat)](https://godoc.org/github.com/gofrs/flock)
+[![License](https://img.shields.io/badge/license-BSD_3--Clause-brightgreen.svg?style=flat)](https://github.com/gofrs/flock/blob/master/LICENSE)
+[![Go Report Card](https://goreportcard.com/badge/github.com/gofrs/flock)](https://goreportcard.com/report/github.com/gofrs/flock)
+
+`flock` implements a thread-safe sync.Locker interface for file locking. It also
+includes a non-blocking TryLock() function to allow locking without blocking execution.
+
+## License
+`flock` is released under the BSD 3-Clause License. See the `LICENSE` file for more details.
+
+## Go Compatibility
+This package makes use of the `context` package that was introduced in Go 1.7. As such, this
+package has an implicit dependency on Go 1.7+.
+
+## Installation
+```
+go get -u github.com/gofrs/flock
+```
+
+## Usage
+```Go
+import "github.com/gofrs/flock"
+
+fileLock := flock.New("/var/lock/go-lock.lock")
+
+locked, err := fileLock.TryLock()
+
+if err != nil {
+	// handle locking error
+}
+
+if locked {
+	// do work
+	fileLock.Unlock()
+}
+```
+
+For more detailed usage information take a look at the package API docs on
+[GoDoc](https://godoc.org/github.com/gofrs/flock).

vendor/github.com/gofrs/flock/appveyor.yml

@@ -0,0 +1,25 @@
+version: '{build}'
+
+build: false
+deploy: false
+
+clone_folder: 'c:\gopath\src\github.com\gofrs\flock'
+
+environment:
+  GOPATH: 'c:\gopath'
+  GOVERSION: '1.15'
+
+init:
+  - git config --global core.autocrlf input
+
+install:
+  - rmdir c:\go /s /q
+  - appveyor DownloadFile https://storage.googleapis.com/golang/go%GOVERSION%.windows-amd64.msi
+  - msiexec /i go%GOVERSION%.windows-amd64.msi /q
+  - set Path=c:\go\bin;c:\gopath\bin;%Path%
+  - go version
+  - go env
+
+test_script:
+  - go get -t ./...
+  - go test -race -v ./...

vendor/github.com/gofrs/flock/flock.go

@@ -0,0 +1,144 @@
+// Copyright 2015 Tim Heckman. All rights reserved.
+// Use of this source code is governed by the BSD 3-Clause
+// license that can be found in the LICENSE file.
+
+// Package flock implements a thread-safe interface for file locking.
+// It also includes a non-blocking TryLock() function to allow locking
+// without blocking execution.
+//
+// Package flock is released under the BSD 3-Clause License. See the LICENSE file
+// for more details.
+//
+// While using this library, remember that the locking behaviors are not
+// guaranteed to be the same on each platform. For example, some UNIX-like
+// operating systems will transparently convert a shared lock to an exclusive
+// lock. If you Unlock() the flock from a location where you believe that you
+// have the shared lock, you may accidentally drop the exclusive lock.
+package flock
+
+import (
+	"context"
+	"os"
+	"runtime"
+	"sync"
+	"time"
+)
+
+// Flock is the struct type to handle file locking. All fields are unexported,
+// with access to some of the fields provided by getter methods (Path() and Locked()).
+type Flock struct {
+	path string
+	m    sync.RWMutex
+	fh   *os.File
+	l    bool
+	r    bool
+}
+
+// New returns a new instance of *Flock. The only parameter
+// it takes is the path to the desired lockfile.
+func New(path string) *Flock {
+	return &Flock{path: path}
+}
+
+// NewFlock returns a new instance of *Flock. The only parameter
+// it takes is the path to the desired lockfile.
+//
+// Deprecated: Use New instead.
+func NewFlock(path string) *Flock {
+	return New(path)
+}
+
+// Close is equivalent to calling Unlock.
+//
+// This will release the lock and close the underlying file descriptor.
+// It will not remove the file from disk, that's up to your application.
+func (f *Flock) Close() error {
+	return f.Unlock()
+}
+
+// Path returns the path as provided in NewFlock().
+func (f *Flock) Path() string {
+	return f.path
+}
+
+// Locked returns the lock state (locked: true, unlocked: false).
+//
+// Warning: by the time you use the returned value, the state may have changed.
+func (f *Flock) Locked() bool {
+	f.m.RLock()
+	defer f.m.RUnlock()
+	return f.l
+}
+
+// RLocked returns the read lock state (locked: true, unlocked: false).
+//
+// Warning: by the time you use the returned value, the state may have changed.
+func (f *Flock) RLocked() bool {
+	f.m.RLock()
+	defer f.m.RUnlock()
+	return f.r
+}
+
+func (f *Flock) String() string {
+	return f.path
+}
+
+// TryLockContext repeatedly tries to take an exclusive lock until one of the
+// conditions is met: TryLock succeeds, TryLock fails with error, or Context
+// Done channel is closed.
+func (f *Flock) TryLockContext(ctx context.Context, retryDelay time.Duration) (bool, error) {
+	return tryCtx(ctx, f.TryLock, retryDelay)
+}
+
+// TryRLockContext repeatedly tries to take a shared lock until one of the
+// conditions is met: TryRLock succeeds, TryRLock fails with error, or Context
+// Done channel is closed.
+func (f *Flock) TryRLockContext(ctx context.Context, retryDelay time.Duration) (bool, error) {
+	return tryCtx(ctx, f.TryRLock, retryDelay)
+}
+
+func tryCtx(ctx context.Context, fn func() (bool, error), retryDelay time.Duration) (bool, error) {
+	if ctx.Err() != nil {
+		return false, ctx.Err()
+	}
+	for {
+		if ok, err := fn(); ok || err != nil {
+			return ok, err
+		}
+		select {
+		case <-ctx.Done():
+			return false, ctx.Err()
+		case <-time.After(retryDelay):
+			// try again
+		}
+	}
+}
+
+func (f *Flock) setFh() error {
+	// open a new os.File instance
+	// create it if it doesn't exist, and open the file read-only.
+	flags := os.O_CREATE
+	if runtime.GOOS == "aix" {
+		// AIX cannot preform write-lock (ie exclusive) on a
+		// read-only file.
+		flags |= os.O_RDWR
+	} else {
+		flags |= os.O_RDONLY
+	}
+	fh, err := os.OpenFile(f.path, flags, os.FileMode(0600))
+	if err != nil {
+		return err
+	}
+
+	// set the filehandle on the struct
+	f.fh = fh
+	return nil
+}
+
+// ensure the file handle is closed if no lock is held
+func (f *Flock) ensureFhState() {
+	if !f.l && !f.r && f.fh != nil {
+		f.fh.Close()
+		f.fh = nil
+	}
+}

vendor/github.com/gofrs/flock/flock_aix.go

@@ -0,0 +1,281 @@
+// Copyright 2019 Tim Heckman. All rights reserved. Use of this source code is
+// governed by the BSD 3-Clause license that can be found in the LICENSE file.
+
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This code implements the filelock API using POSIX 'fcntl' locks, which attach
+// to an (inode, process) pair rather than a file descriptor. To avoid unlocking
+// files prematurely when the same file is opened through different descriptors,
+// we allow only one read-lock at a time.
+//
+// This code is adapted from the Go package:
+// cmd/go/internal/lockedfile/internal/filelock
+
+//+build aix
+
+package flock
+
+import (
+	"errors"
+	"io"
+	"os"
+	"sync"
+	"syscall"
+
+	"golang.org/x/sys/unix"
+)
+
+type lockType int16
+
+const (
+	readLock  lockType = unix.F_RDLCK
+	writeLock lockType = unix.F_WRLCK
+)
+
+type cmdType int
+
+const (
+	tryLock  cmdType = unix.F_SETLK
+	waitLock cmdType = unix.F_SETLKW
+)
+
+type inode = uint64
+
+type inodeLock struct {
+	owner *Flock
+	queue []<-chan *Flock
+}
+
+var (
+	mu     sync.Mutex
+	inodes = map[*Flock]inode{}
+	locks  = map[inode]inodeLock{}
+)
+
+// Lock is a blocking call to try and take an exclusive file lock. It will wait
+// until it is able to obtain the exclusive file lock. It's recommended that
+// TryLock() be used over this function. This function may block the ability to
+// query the current Locked() or RLocked() status due to a RW-mutex lock.
+//
+// If we are already exclusive-locked, this function short-circuits and returns
+// immediately assuming it can take the mutex lock.
+//
+// If the *Flock has a shared lock (RLock), this may transparently replace the
+// shared lock with an exclusive lock on some UNIX-like operating systems. Be
+// careful when using exclusive locks in conjunction with shared locks
+// (RLock()), because calling Unlock() may accidentally release the exclusive
+// lock that was once a shared lock.
+func (f *Flock) Lock() error {
+	return f.lock(&f.l, writeLock)
+}
+
+// RLock is a blocking call to try and take a shared file lock. It will wait
+// until it is able to obtain the shared file lock. It's recommended that
+// TryRLock() be used over this function. This function may block the ability to
+// query the current Locked() or RLocked() status due to a RW-mutex lock.
+//
+// If we are already shared-locked, this function short-circuits and returns
+// immediately assuming it can take the mutex lock.
+func (f *Flock) RLock() error {
+	return f.lock(&f.r, readLock)
+}
+
+func (f *Flock) lock(locked *bool, flag lockType) error {
+	f.m.Lock()
+	defer f.m.Unlock()
+
+	if *locked {
+		return nil
+	}
+
+	if f.fh == nil {
+		if err := f.setFh(); err != nil {
+			return err
+		}
+		defer f.ensureFhState()
+	}
+
+	if _, err := f.doLock(waitLock, flag, true); err != nil {
+		return err
+	}
+
+	*locked = true
+	return nil
+}
+
+func (f *Flock) doLock(cmd cmdType, lt lockType, blocking bool) (bool, error) {
+	// POSIX locks apply per inode and process, and the lock for an inode is
+	// released when *any* descriptor for that inode is closed. So we need to
+	// synchronize access to each inode internally, and must serialize lock and
+	// unlock calls that refer to the same inode through different descriptors.
+	fi, err := f.fh.Stat()
+	if err != nil {
+		return false, err
+	}
+	ino := inode(fi.Sys().(*syscall.Stat_t).Ino)
+
+	mu.Lock()
+	if i, dup := inodes[f]; dup && i != ino {
+		mu.Unlock()
+		return false, &os.PathError{
+			Path: f.Path(),
+			Err:  errors.New("inode for file changed since last Lock or RLock"),
+		}
+	}
+
+	inodes[f] = ino
+
+	var wait chan *Flock
+	l := locks[ino]
+	if l.owner == f {
+		// This file already owns the lock, but the call may change its lock type.
+	} else if l.owner == nil {
+		// No owner: it's ours now.
+		l.owner = f
+	} else if !blocking {
+		// Already owned: cannot take the lock.
+		mu.Unlock()
+		return false, nil
+	} else {
+		// Already owned: add a channel to wait on.
+		wait = make(chan *Flock)
+		l.queue = append(l.queue, wait)
+	}
+	locks[ino] = l
+	mu.Unlock()
+
+	if wait != nil {
+		wait <- f
+	}
+
+	err = setlkw(f.fh.Fd(), cmd, lt)
+
+	if err != nil {
+		f.doUnlock()
+		if cmd == tryLock && err == unix.EACCES {
+			return false, nil
+		}
+		return false, err
+	}
+
+	return true, nil
+}
+
+func (f *Flock) Unlock() error {
+	f.m.Lock()
+	defer f.m.Unlock()
+
+	// if we aren't locked or if the lockfile instance is nil
+	// just return a nil error because we are unlocked
+	if (!f.l && !f.r) || f.fh == nil {
+		return nil
+	}
+
+	if err := f.doUnlock(); err != nil {
+		return err
+	}
+
+	f.fh.Close()
+
+	f.l = false
+	f.r = false
+	f.fh = nil
+
+	return nil
+}
+
+func (f *Flock) doUnlock() (err error) {
+	var owner *Flock
+	mu.Lock()
+	ino, ok := inodes[f]
+	if ok {
+		owner = locks[ino].owner
+	}
+	mu.Unlock()
+
+	if owner == f {
+		err = setlkw(f.fh.Fd(), waitLock, unix.F_UNLCK)
+	}
+
+	mu.Lock()
+	l := locks[ino]
+	if len(l.queue) == 0 {
+		// No waiters: remove the map entry.
+		delete(locks, ino)
+	} else {
+		// The first waiter is sending us their file now.
+		// Receive it and update the queue.
+		l.owner = <-l.queue[0]
+		l.queue = l.queue[1:]
+		locks[ino] = l
+	}
+	delete(inodes, f)
+	mu.Unlock()
+
+	return err
+}
+
+// TryLock is the preferred function for taking an exclusive file lock. This
+// function takes an RW-mutex lock before it tries to lock the file, so there is
+// the possibility that this function may block for a short time if another
+// goroutine is trying to take any action.
+//
+// The actual file lock is non-blocking. If we are unable to get the exclusive
+// file lock, the function will return false instead of waiting for the lock. If
+// we get the lock, we also set the *Flock instance as being exclusive-locked.
+func (f *Flock) TryLock() (bool, error) {
+	return f.try(&f.l, writeLock)
+}
+
+// TryRLock is the preferred function for taking a shared file lock. This
+// function takes an RW-mutex lock before it tries to lock the file, so there is
+// the possibility that this function may block for a short time if another
+// goroutine is trying to take any action.
+//
+// The actual file lock is non-blocking. If we are unable to get the shared file
+// lock, the function will return false instead of waiting for the lock. If we
+// get the lock, we also set the *Flock instance as being share-locked.
+func (f *Flock) TryRLock() (bool, error) {
+	return f.try(&f.r, readLock)
+}
+
+func (f *Flock) try(locked *bool, flag lockType) (bool, error) {
+	f.m.Lock()
+	defer f.m.Unlock()
+
+	if *locked {
+		return true, nil
+	}
+
+	if f.fh == nil {
+		if err := f.setFh(); err != nil {
+			return false, err
+		}
+		defer f.ensureFhState()
+	}
+
+	haslock, err := f.doLock(tryLock, flag, false)
+	if err != nil {
+		return false, err
+	}
+
+	*locked = haslock
+	return haslock, nil
+}
+
+// setlkw calls FcntlFlock with cmd for the entire file indicated by fd.
+func setlkw(fd uintptr, cmd cmdType, lt lockType) error {
+	for {
+		err := unix.FcntlFlock(fd, int(cmd), &unix.Flock_t{
+			Type:   int16(lt),
+			Whence: io.SeekStart,
+			Start:  0,
+			Len:    0, // All bytes.
+		})
+		if err != unix.EINTR {
+			return err
+		}
+	}
+}

vendor/github.com/gofrs/flock/flock_unix.go

@@ -0,0 +1,197 @@
+// Copyright 2015 Tim Heckman. All rights reserved.
+// Use of this source code is governed by the BSD 3-Clause
+// license that can be found in the LICENSE file.
+
+// +build !aix,!windows
+
+package flock
+
+import (
+	"os"
+	"syscall"
+)
+
+// Lock is a blocking call to try and take an exclusive file lock. It will wait
+// until it is able to obtain the exclusive file lock. It's recommended that
+// TryLock() be used over this function. This function may block the ability to
+// query the current Locked() or RLocked() status due to a RW-mutex lock.
+//
+// If we are already exclusive-locked, this function short-circuits and returns
+// immediately assuming it can take the mutex lock.
+//
+// If the *Flock has a shared lock (RLock), this may transparently replace the
+// shared lock with an exclusive lock on some UNIX-like operating systems. Be
+// careful when using exclusive locks in conjunction with shared locks
+// (RLock()), because calling Unlock() may accidentally release the exclusive
+// lock that was once a shared lock.
+func (f *Flock) Lock() error {
+	return f.lock(&f.l, syscall.LOCK_EX)
+}
+
+// RLock is a blocking call to try and take a shared file lock. It will wait
+// until it is able to obtain the shared file lock. It's recommended that
+// TryRLock() be used over this function. This function may block the ability to
+// query the current Locked() or RLocked() status due to a RW-mutex lock.
+//
+// If we are already shared-locked, this function short-circuits and returns
+// immediately assuming it can take the mutex lock.
+func (f *Flock) RLock() error {
+	return f.lock(&f.r, syscall.LOCK_SH)
+}
+
+func (f *Flock) lock(locked *bool, flag int) error {
+	f.m.Lock()
+	defer f.m.Unlock()
+
+	if *locked {
+		return nil
+	}
+
+	if f.fh == nil {
+		if err := f.setFh(); err != nil {
+			return err
+		}
+		defer f.ensureFhState()
+	}
+
+	if err := syscall.Flock(int(f.fh.Fd()), flag); err != nil {
+		shouldRetry, reopenErr := f.reopenFDOnError(err)
+		if reopenErr != nil {
+			return reopenErr
+		}
+
+		if !shouldRetry {
+			return err
+		}
+
+		if err = syscall.Flock(int(f.fh.Fd()), flag); err != nil {
+			return err
+		}
+	}
+
+	*locked = true
+	return nil
+}
+
+// Unlock is a function to unlock the file. This file takes a RW-mutex lock, so
+// while it is running the Locked() and RLocked() functions will be blocked.
+//
+// This function short-circuits if we are unlocked already. If not, it calls
+// syscall.LOCK_UN on the file and closes the file descriptor. It does not
+// remove the file from disk. It's up to your application to do.
+//
+// Please note, if your shared lock became an exclusive lock this may
+// unintentionally drop the exclusive lock if called by the consumer that
+// believes they have a shared lock. Please see Lock() for more details.
+func (f *Flock) Unlock() error {
+	f.m.Lock()
+	defer f.m.Unlock()
+
+	// if we aren't locked or if the lockfile instance is nil
+	// just return a nil error because we are unlocked
+	if (!f.l && !f.r) || f.fh == nil {
+		return nil
+	}
+
+	// mark the file as unlocked
+	if err := syscall.Flock(int(f.fh.Fd()), syscall.LOCK_UN); err != nil {
+		return err
+	}
+
+	f.fh.Close()
+
+	f.l = false
+	f.r = false
+	f.fh = nil
+
+	return nil
+}
+
+// TryLock is the preferred function for taking an exclusive file lock. This
+// function takes an RW-mutex lock before it tries to lock the file, so there is
+// the possibility that this function may block for a short time if another
+// goroutine is trying to take any action.
+//
+// The actual file lock is non-blocking. If we are unable to get the exclusive
+// file lock, the function will return false instead of waiting for the lock. If
+// we get the lock, we also set the *Flock instance as being exclusive-locked.
+func (f *Flock) TryLock() (bool, error) {
+	return f.try(&f.l, syscall.LOCK_EX)
+}
+
+// TryRLock is the preferred function for taking a shared file lock. This
+// function takes an RW-mutex lock before it tries to lock the file, so there is
+// the possibility that this function may block for a short time if another
+// goroutine is trying to take any action.
+//
+// The actual file lock is non-blocking. If we are unable to get the shared file
+// lock, the function will return false instead of waiting for the lock. If we
+// get the lock, we also set the *Flock instance as being share-locked.
+func (f *Flock) TryRLock() (bool, error) {
+	return f.try(&f.r, syscall.LOCK_SH)
+}
+
+func (f *Flock) try(locked *bool, flag int) (bool, error) {
+	f.m.Lock()
+	defer f.m.Unlock()
+
+	if *locked {
+		return true, nil
+	}
+
+	if f.fh == nil {
+		if err := f.setFh(); err != nil {
+			return false, err
+		}
+		defer f.ensureFhState()
+	}
+
+	var retried bool
+retry:
+	err := syscall.Flock(int(f.fh.Fd()), flag|syscall.LOCK_NB)
+
+	switch err {
+	case syscall.EWOULDBLOCK:
+		return false, nil
+	case nil:
+		*locked = true
+		return true, nil
+	}
+	if !retried {
+		if shouldRetry, reopenErr := f.reopenFDOnError(err); reopenErr != nil {
+			return false, reopenErr
+		} else if shouldRetry {
+			retried = true
+			goto retry
+		}
+	}
+
+	return false, err
+}
+
+// reopenFDOnError determines whether we should reopen the file handle
+// in readwrite mode and try again. This comes from util-linux/sys-utils/flock.c:
+//  Since Linux 3.4 (commit 55725513)
+//  Probably NFSv4 where flock() is emulated by fcntl().
+func (f *Flock) reopenFDOnError(err error) (bool, error) {
+	if err != syscall.EIO && err != syscall.EBADF {
+		return false, nil
+	}
+	if st, err := f.fh.Stat(); err == nil {
+		// if the file is able to be read and written
+		if st.Mode()&0600 == 0600 {
+			f.fh.Close()
+			f.fh = nil
+
+			// reopen in read-write mode and set the filehandle
+			fh, err := os.OpenFile(f.path, os.O_CREATE|os.O_RDWR, os.FileMode(0600))
+			if err != nil {
+				return false, err
+			}
+			f.fh = fh
+			return true, nil
+		}
+	}
+
+	return false, nil
+}

vendor/github.com/gofrs/flock/flock_winapi.go

@@ -0,0 +1,76 @@
+// Copyright 2015 Tim Heckman. All rights reserved.
+// Use of this source code is governed by the BSD 3-Clause
+// license that can be found in the LICENSE file.
+
+// +build windows
+
+package flock
+
+import (
+	"syscall"
+	"unsafe"
+)
+
+var (
+	kernel32, _         = syscall.LoadLibrary("kernel32.dll")
+	procLockFileEx, _   = syscall.GetProcAddress(kernel32, "LockFileEx")
+	procUnlockFileEx, _ = syscall.GetProcAddress(kernel32, "UnlockFileEx")
+)
+
+const (
+	winLockfileFailImmediately = 0x00000001
+	winLockfileExclusiveLock   = 0x00000002
+	winLockfileSharedLock      = 0x00000000
+)
+
+// Use of 0x00000000 for the shared lock is a guess based on some the MS Windows
+// `LockFileEX` docs, which document the `LOCKFILE_EXCLUSIVE_LOCK` flag as:
+//
+// > The function requests an exclusive lock. Otherwise, it requests a shared
+// > lock.
+//
+// https://msdn.microsoft.com/en-us/library/windows/desktop/aa365203(v=vs.85).aspx
+
+func lockFileEx(handle syscall.Handle, flags uint32, reserved uint32, numberOfBytesToLockLow uint32, numberOfBytesToLockHigh uint32, offset *syscall.Overlapped) (bool, syscall.Errno) {
+	r1, _, errNo := syscall.Syscall6(
+		uintptr(procLockFileEx),
+		6,
+		uintptr(handle),
+		uintptr(flags),
+		uintptr(reserved),
+		uintptr(numberOfBytesToLockLow),
+		uintptr(numberOfBytesToLockHigh),
+		uintptr(unsafe.Pointer(offset)))
+
+	if r1 != 1 {
+		if errNo == 0 {
+			return false, syscall.EINVAL
+		}
+
+		return false, errNo
+	}
+
+	return true, 0
+}
+
+func unlockFileEx(handle syscall.Handle, reserved uint32, numberOfBytesToLockLow uint32, numberOfBytesToLockHigh uint32, offset *syscall.Overlapped) (bool, syscall.Errno) {
+	r1, _, errNo := syscall.Syscall6(
+		uintptr(procUnlockFileEx),
+		5,
+		uintptr(handle),
+		uintptr(reserved),
+		uintptr(numberOfBytesToLockLow),
+		uintptr(numberOfBytesToLockHigh),
+		uintptr(unsafe.Pointer(offset)),
+		0)
+
+	if r1 != 1 {
+		if errNo == 0 {
+			return false, syscall.EINVAL
+		}
+
+		return false, errNo
+	}
+
+	return true, 0
+}

vendor/github.com/gofrs/flock/flock_windows.go

@@ -0,0 +1,142 @@
+// Copyright 2015 Tim Heckman. All rights reserved.
+// Use of this source code is governed by the BSD 3-Clause
+// license that can be found in the LICENSE file.
+
+package flock
+
+import (
+	"syscall"
+)
+
+// ErrorLockViolation is the error code returned from the Windows syscall when a
+// lock would block and you ask to fail immediately.
+const ErrorLockViolation syscall.Errno = 0x21 // 33
+
+// Lock is a blocking call to try and take an exclusive file lock. It will wait
+// until it is able to obtain the exclusive file lock. It's recommended that
+// TryLock() be used over this function. This function may block the ability to
+// query the current Locked() or RLocked() status due to a RW-mutex lock.
+//
+// If we are already locked, this function short-circuits and returns
+// immediately assuming it can take the mutex lock.
+func (f *Flock) Lock() error {
+	return f.lock(&f.l, winLockfileExclusiveLock)
+}
+
+// RLock is a blocking call to try and take a shared file lock. It will wait
+// until it is able to obtain the shared file lock. It's recommended that
+// TryRLock() be used over this function. This function may block the ability to
+// query the current Locked() or RLocked() status due to a RW-mutex lock.
+//
+// If we are already locked, this function short-circuits and returns
+// immediately assuming it can take the mutex lock.
+func (f *Flock) RLock() error {
+	return f.lock(&f.r, winLockfileSharedLock)
+}
+
+func (f *Flock) lock(locked *bool, flag uint32) error {
+	f.m.Lock()
+	defer f.m.Unlock()
+
+	if *locked {
+		return nil
+	}
+
+	if f.fh == nil {
+		if err := f.setFh(); err != nil {
+			return err
+		}
+		defer f.ensureFhState()
+	}
+
+	if _, errNo := lockFileEx(syscall.Handle(f.fh.Fd()), flag, 0, 1, 0, &syscall.Overlapped{}); errNo > 0 {
+		return errNo
+	}
+
+	*locked = true
+	return nil
+}
+
+// Unlock is a function to unlock the file. This file takes a RW-mutex lock, so
+// while it is running the Locked() and RLocked() functions will be blocked.
+//
+// This function short-circuits if we are unlocked already. If not, it calls
+// UnlockFileEx() on the file and closes the file descriptor. It does not remove
+// the file from disk. It's up to your application to do.
+func (f *Flock) Unlock() error {
+	f.m.Lock()
+	defer f.m.Unlock()
+
+	// if we aren't locked or if the lockfile instance is nil
+	// just return a nil error because we are unlocked
+	if (!f.l && !f.r) || f.fh == nil {
+		return nil
+	}
+
+	// mark the file as unlocked
+	if _, errNo := unlockFileEx(syscall.Handle(f.fh.Fd()), 0, 1, 0, &syscall.Overlapped{}); errNo > 0 {
+		return errNo
+	}
+
+	f.fh.Close()
+
+	f.l = false
+	f.r = false
+	f.fh = nil
+
+	return nil
+}
+
+// TryLock is the preferred function for taking an exclusive file lock. This
+// function does take a RW-mutex lock before it tries to lock the file, so there
+// is the possibility that this function may block for a short time if another
+// goroutine is trying to take any action.
+//
+// The actual file lock is non-blocking. If we are unable to get the exclusive
+// file lock, the function will return false instead of waiting for the lock. If
+// we get the lock, we also set the *Flock instance as being exclusive-locked.
+func (f *Flock) TryLock() (bool, error) {
+	return f.try(&f.l, winLockfileExclusiveLock)
+}
+
+// TryRLock is the preferred function for taking a shared file lock. This
+// function does take a RW-mutex lock before it tries to lock the file, so there
+// is the possibility that this function may block for a short time if another
+// goroutine is trying to take any action.
+//
+// The actual file lock is non-blocking. If we are unable to get the shared file
+// lock, the function will return false instead of waiting for the lock. If we
+// get the lock, we also set the *Flock instance as being shared-locked.
+func (f *Flock) TryRLock() (bool, error) {
+	return f.try(&f.r, winLockfileSharedLock)
+}
+
+func (f *Flock) try(locked *bool, flag uint32) (bool, error) {
+	f.m.Lock()
+	defer f.m.Unlock()
+
+	if *locked {
+		return true, nil
+	}
+
+	if f.fh == nil {
+		if err := f.setFh(); err != nil {
+			return false, err
+		}
+		defer f.ensureFhState()
+	}
+
+	_, errNo := lockFileEx(syscall.Handle(f.fh.Fd()), flag|winLockfileFailImmediately, 0, 1, 0, &syscall.Overlapped{})
+
+	if errNo > 0 {
+		if errNo == ErrorLockViolation || errNo == syscall.ERROR_IO_PENDING {
+			return false, nil
+		}
+
+		return false, errNo
+	}
+
+	*locked = true
+
+	return true, nil
+}

vendor/github.com/gofrs/uuid/.gitignore

@@ -0,0 +1,15 @@
+# Binaries for programs and plugins
+*.exe
+*.exe~
+*.dll
+*.so
+*.dylib
+
+# Test binary, build with `go test -c`
+*.test
+
+# Output of the go coverage tool, specifically when used with LiteIDE
+*.out
+
+# binary bundle generated by go-fuzz
+uuid-fuzz.zip

vendor/github.com/gofrs/uuid/LICENSE

@@ -0,0 +1,20 @@
+Copyright (C) 2013-2018 by Maxim Bublis <b@codemonkey.ru>
+
+Permission is hereby granted, free of charge, to any person obtaining
+a copy of this software and associated documentation files (the
+"Software"), to deal in the Software without restriction, including
+without limitation the rights to use, copy, modify, merge, publish,
+distribute, sublicense, and/or sell copies of the Software, and to
+permit persons to whom the Software is furnished to do so, subject to
+the following conditions:
+
+The above copyright notice and this permission notice shall be
+included in all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

vendor/github.com/gofrs/uuid/README.md

@@ -0,0 +1,117 @@
+# UUID
+
+[![License](https://img.shields.io/github/license/gofrs/uuid.svg)](https://github.com/gofrs/uuid/blob/master/LICENSE)
+[![Build Status](https://travis-ci.org/gofrs/uuid.svg?branch=master)](https://travis-ci.org/gofrs/uuid)
+[![GoDoc](http://godoc.org/github.com/gofrs/uuid?status.svg)](http://godoc.org/github.com/gofrs/uuid)
+[![Coverage Status](https://codecov.io/gh/gofrs/uuid/branch/master/graphs/badge.svg?branch=master)](https://codecov.io/gh/gofrs/uuid/)
+[![Go Report Card](https://goreportcard.com/badge/github.com/gofrs/uuid)](https://goreportcard.com/report/github.com/gofrs/uuid)
+
+Package uuid provides a pure Go implementation of Universally Unique Identifiers
+(UUID) variant as defined in RFC-4122. This package supports both the creation
+and parsing of UUIDs in different formats.
+
+This package supports the following UUID versions:
+* Version 1, based on timestamp and MAC address (RFC-4122)
+* Version 3, based on MD5 hashing of a named value (RFC-4122)
+* Version 4, based on random numbers (RFC-4122)
+* Version 5, based on SHA-1 hashing of a named value (RFC-4122)
+
+This package also supports experimental Universally Unique Identifier implementations based on a
+[draft RFC](https://www.ietf.org/archive/id/draft-peabody-dispatch-new-uuid-format-04.html) that updates RFC-4122
+* Version 6, a k-sortable id based on timestamp, and field-compatible with v1 (draft-peabody-dispatch-new-uuid-format, RFC-4122)
+* Version 7, a k-sortable id based on timestamp (draft-peabody-dispatch-new-uuid-format, RFC-4122)
+
+The v6 and v7 IDs are **not** considered a part of the stable API, and may be subject to behavior or API changes as part of minor releases
+to this package. They will be updated as the draft RFC changes, and will become stable if and when the draft RFC is accepted.
+
+## Project History
+
+This project was originally forked from the
+[github.com/satori/go.uuid](https://github.com/satori/go.uuid) repository after
+it appeared to be no longer maintained, while exhibiting [critical
+flaws](https://github.com/satori/go.uuid/issues/73). We have decided to take
+over this project to ensure it receives regular maintenance for the benefit of
+the larger Go community.
+
+We'd like to thank Maxim Bublis for his hard work on the original iteration of
+the package.
+
+## License
+
+This source code of this package is released under the MIT License. Please see
+the [LICENSE](https://github.com/gofrs/uuid/blob/master/LICENSE) for the full
+content of the license.
+
+## Recommended Package Version
+
+We recommend using v2.0.0+ of this package, as versions prior to 2.0.0 were
+created before our fork of the original package and have some known
+deficiencies.
+
+## Installation
+
+It is recommended to use a package manager like `dep` that understands tagged
+releases of a package, as well as semantic versioning.
+
+If you are unable to make use of a dependency manager with your project, you can
+use the `go get` command to download it directly:
+
+```Shell
+$ go get github.com/gofrs/uuid
+```
+
+## Requirements
+
+Due to subtests not being supported in older versions of Go, this package is
+only regularly tested against Go 1.7+. This package may work perfectly fine with
+Go 1.2+, but support for these older versions is not actively maintained.
+
+## Go 1.11 Modules
+
+As of v3.2.0, this repository no longer adopts Go modules, and v3.2.0 no longer has a `go.mod` file.  As a result, v3.2.0 also drops support for the `github.com/gofrs/uuid/v3` import path. Only module-based consumers are impacted.  With the v3.2.0 release, _all_ gofrs/uuid consumers should use the `github.com/gofrs/uuid` import path.
+
+An existing module-based consumer will continue to be able to build using the `github.com/gofrs/uuid/v3` import path using any valid consumer `go.mod` that worked prior to the publishing of v3.2.0, but any module-based consumer should start using the `github.com/gofrs/uuid` import path when possible and _must_ use the `github.com/gofrs/uuid` import path prior to upgrading to v3.2.0.
+
+Please refer to [Issue #61](https://github.com/gofrs/uuid/issues/61) and [Issue #66](https://github.com/gofrs/uuid/issues/66) for more details.
+
+## Usage
+
+Here is a quick overview of how to use this package. For more detailed
+documentation, please see the [GoDoc Page](http://godoc.org/github.com/gofrs/uuid).
+
+```go
+package main
+
+import (
+	"log"
+
+	"github.com/gofrs/uuid"
+)
+
+// Create a Version 4 UUID, panicking on error.
+// Use this form to initialize package-level variables.
+var u1 = uuid.Must(uuid.NewV4())
+
+func main() {
+	// Create a Version 4 UUID.
+	u2, err := uuid.NewV4()
+	if err != nil {
+		log.Fatalf("failed to generate UUID: %v", err)
+	}
+	log.Printf("generated Version 4 UUID %v", u2)
+
+	// Parse a UUID from a string.
+	s := "6ba7b810-9dad-11d1-80b4-00c04fd430c8"
+	u3, err := uuid.FromString(s)
+	if err != nil {
+		log.Fatalf("failed to parse UUID %q: %v", s, err)
+	}
+	log.Printf("successfully parsed UUID %v", u3)
+}
+```
+
+## References
+
+* [RFC-4122](https://tools.ietf.org/html/rfc4122)
+* [DCE 1.1: Authentication and Security Services](http://pubs.opengroup.org/onlinepubs/9696989899/chap5.htm#tagcjh_08_02_01_01)
+* [New UUID Formats RFC Draft (Peabody) Rev 04](https://www.ietf.org/archive/id/draft-peabody-dispatch-new-uuid-format-04.html#)

vendor/github.com/gofrs/uuid/codec.go

@@ -0,0 +1,234 @@
+// Copyright (C) 2013-2018 by Maxim Bublis <b@codemonkey.ru>
+//
+// Permission is hereby granted, free of charge, to any person obtaining
+// a copy of this software and associated documentation files (the
+// "Software"), to deal in the Software without restriction, including
+// without limitation the rights to use, copy, modify, merge, publish,
+// distribute, sublicense, and/or sell copies of the Software, and to
+// permit persons to whom the Software is furnished to do so, subject to
+// the following conditions:
+//
+// The above copyright notice and this permission notice shall be
+// included in all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+// LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+// OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+// WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+package uuid
+
+import (
+	"errors"
+	"fmt"
+)
+
+// FromBytes returns a UUID generated from the raw byte slice input.
+// It will return an error if the slice isn't 16 bytes long.
+func FromBytes(input []byte) (UUID, error) {
+	u := UUID{}
+	err := u.UnmarshalBinary(input)
+	return u, err
+}
+
+// FromBytesOrNil returns a UUID generated from the raw byte slice input.
+// Same behavior as FromBytes(), but returns uuid.Nil instead of an error.
+func FromBytesOrNil(input []byte) UUID {
+	uuid, err := FromBytes(input)
+	if err != nil {
+		return Nil
+	}
+	return uuid
+}
+
+var errInvalidFormat = errors.New("uuid: invalid UUID format")
+
+func fromHexChar(c byte) byte {
+	switch {
+	case '0' <= c && c <= '9':
+		return c - '0'
+	case 'a' <= c && c <= 'f':
+		return c - 'a' + 10
+	case 'A' <= c && c <= 'F':
+		return c - 'A' + 10
+	}
+	return 255
+}
+
+// Parse parses the UUID stored in the string text. Parsing and supported
+// formats are the same as UnmarshalText.
+func (u *UUID) Parse(s string) error {
+	switch len(s) {
+	case 32: // hash
+	case 36: // canonical
+	case 34, 38:
+		if s[0] != '{' || s[len(s)-1] != '}' {
+			return fmt.Errorf("uuid: incorrect UUID format in string %q", s)
+		}
+		s = s[1 : len(s)-1]
+	case 41, 45:
+		if s[:9] != "urn:uuid:" {
+			return fmt.Errorf("uuid: incorrect UUID format in string %q", s[:9])
+		}
+		s = s[9:]
+	default:
+		return fmt.Errorf("uuid: incorrect UUID length %d in string %q", len(s), s)
+	}
+	// canonical
+	if len(s) == 36 {
+		if s[8] != '-' || s[13] != '-' || s[18] != '-' || s[23] != '-' {
+			return fmt.Errorf("uuid: incorrect UUID format in string %q", s)
+		}
+		for i, x := range [16]byte{
+			0, 2, 4, 6,
+			9, 11,
+			14, 16,
+			19, 21,
+			24, 26, 28, 30, 32, 34,
+		} {
+			v1 := fromHexChar(s[x])
+			v2 := fromHexChar(s[x+1])
+			if v1|v2 == 255 {
+				return errInvalidFormat
+			}
+			u[i] = (v1 << 4) | v2
+		}
+		return nil
+	}
+	// hash like
+	for i := 0; i < 32; i += 2 {
+		v1 := fromHexChar(s[i])
+		v2 := fromHexChar(s[i+1])
+		if v1|v2 == 255 {
+			return errInvalidFormat
+		}
+		u[i/2] = (v1 << 4) | v2
+	}
+	return nil
+}
+
+// FromString returns a UUID parsed from the input string.
+// Input is expected in a form accepted by UnmarshalText.
+func FromString(text string) (UUID, error) {
+	var u UUID
+	err := u.Parse(text)
+	return u, err
+}
+
+// FromStringOrNil returns a UUID parsed from the input string.
+// Same behavior as FromString(), but returns uuid.Nil instead of an error.
+func FromStringOrNil(input string) UUID {
+	uuid, err := FromString(input)
+	if err != nil {
+		return Nil
+	}
+	return uuid
+}
+
+// MarshalText implements the encoding.TextMarshaler interface.
+// The encoding is the same as returned by the String() method.
+func (u UUID) MarshalText() ([]byte, error) {
+	var buf [36]byte
+	encodeCanonical(buf[:], u)
+	return buf[:], nil
+}
+
+// UnmarshalText implements the encoding.TextUnmarshaler interface.
+// Following formats are supported:
+//
+//	"6ba7b810-9dad-11d1-80b4-00c04fd430c8",
+//	"{6ba7b810-9dad-11d1-80b4-00c04fd430c8}",
+//	"urn:uuid:6ba7b810-9dad-11d1-80b4-00c04fd430c8"
+//	"6ba7b8109dad11d180b400c04fd430c8"
+//	"{6ba7b8109dad11d180b400c04fd430c8}",
+//	"urn:uuid:6ba7b8109dad11d180b400c04fd430c8"
+//
+// ABNF for supported UUID text representation follows:
+//
+//	URN := 'urn'
+//	UUID-NID := 'uuid'
+//
+//	hexdig := '0' | '1' | '2' | '3' | '4' | '5' | '6' | '7' | '8' | '9' |
+//	          'a' | 'b' | 'c' | 'd' | 'e' | 'f' |
+//	          'A' | 'B' | 'C' | 'D' | 'E' | 'F'
+//
+//	hexoct := hexdig hexdig
+//	2hexoct := hexoct hexoct
+//	4hexoct := 2hexoct 2hexoct
+//	6hexoct := 4hexoct 2hexoct
+//	12hexoct := 6hexoct 6hexoct
+//
+//	hashlike := 12hexoct
+//	canonical := 4hexoct '-' 2hexoct '-' 2hexoct '-' 6hexoct
+//
+//	plain := canonical | hashlike
+//	uuid := canonical | hashlike | braced | urn
+//
+//	braced := '{' plain '}' | '{' hashlike  '}'
+//	urn := URN ':' UUID-NID ':' plain
+func (u *UUID) UnmarshalText(b []byte) error {
+	switch len(b) {
+	case 32: // hash
+	case 36: // canonical
+	case 34, 38:
+		if b[0] != '{' || b[len(b)-1] != '}' {
+			return fmt.Errorf("uuid: incorrect UUID format in string %q", b)
+		}
+		b = b[1 : len(b)-1]
+	case 41, 45:
+		if string(b[:9]) != "urn:uuid:" {
+			return fmt.Errorf("uuid: incorrect UUID format in string %q", b[:9])
+		}
+		b = b[9:]
+	default:
+		return fmt.Errorf("uuid: incorrect UUID length %d in string %q", len(b), b)
+	}
+	if len(b) == 36 {
+		if b[8] != '-' || b[13] != '-' || b[18] != '-' || b[23] != '-' {
+			return fmt.Errorf("uuid: incorrect UUID format in string %q", b)
+		}
+		for i, x := range [16]byte{
+			0, 2, 4, 6,
+			9, 11,
+			14, 16,
+			19, 21,
+			24, 26, 28, 30, 32, 34,
+		} {
+			v1 := fromHexChar(b[x])
+			v2 := fromHexChar(b[x+1])
+			if v1|v2 == 255 {
+				return errInvalidFormat
+			}
+			u[i] = (v1 << 4) | v2
+		}
+		return nil
+	}
+	for i := 0; i < 32; i += 2 {
+		v1 := fromHexChar(b[i])
+		v2 := fromHexChar(b[i+1])
+		if v1|v2 == 255 {
+			return errInvalidFormat
+		}
+		u[i/2] = (v1 << 4) | v2
+	}
+	return nil
+}
+
+// MarshalBinary implements the encoding.BinaryMarshaler interface.
+func (u UUID) MarshalBinary() ([]byte, error) {
+	return u.Bytes(), nil
+}
+
+// UnmarshalBinary implements the encoding.BinaryUnmarshaler interface.
+// It will return an error if the slice isn't 16 bytes long.
+func (u *UUID) UnmarshalBinary(data []byte) error {
+	if len(data) != Size {
+		return fmt.Errorf("uuid: UUID must be exactly 16 bytes long, got %d bytes", len(data))
+	}
+	copy(u[:], data)
+
+	return nil
+}

vendor/github.com/gofrs/uuid/fuzz.go

@@ -0,0 +1,48 @@
+// Copyright (c) 2018 Andrei Tudor Călin <mail@acln.ro>
+//
+// Permission is hereby granted, free of charge, to any person obtaining
+// a copy of this software and associated documentation files (the
+// "Software"), to deal in the Software without restriction, including
+// without limitation the rights to use, copy, modify, merge, publish,
+// distribute, sublicense, and/or sell copies of the Software, and to
+// permit persons to whom the Software is furnished to do so, subject to
+// the following conditions:
+//
+// The above copyright notice and this permission notice shall be
+// included in all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+// LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+// OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+// WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+//go:build gofuzz
+// +build gofuzz
+
+package uuid
+
+// Fuzz implements a simple fuzz test for FromString / UnmarshalText.
+//
+// To run:
+//
+//	$ go get github.com/dvyukov/go-fuzz/...
+//	$ cd $GOPATH/src/github.com/gofrs/uuid
+//	$ go-fuzz-build github.com/gofrs/uuid
+//	$ go-fuzz -bin=uuid-fuzz.zip -workdir=./testdata
+//
+// If you make significant changes to FromString / UnmarshalText and add
+// new cases to fromStringTests (in codec_test.go), please run
+//
+//	$ go test -seed_fuzz_corpus
+//
+// to seed the corpus with the new interesting inputs, then run the fuzzer.
+func Fuzz(data []byte) int {
+	_, err := FromString(string(data))
+	if err != nil {
+		return 0
+	}
+	return 1
+}

vendor/github.com/gofrs/uuid/generator.go

@@ -0,0 +1,456 @@
+// Copyright (C) 2013-2018 by Maxim Bublis <b@codemonkey.ru>
+//
+// Permission is hereby granted, free of charge, to any person obtaining
+// a copy of this software and associated documentation files (the
+// "Software"), to deal in the Software without restriction, including
+// without limitation the rights to use, copy, modify, merge, publish,
+// distribute, sublicense, and/or sell copies of the Software, and to
+// permit persons to whom the Software is furnished to do so, subject to
+// the following conditions:
+//
+// The above copyright notice and this permission notice shall be
+// included in all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+// LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+// OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+// WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+package uuid
+
+import (
+	"crypto/md5"
+	"crypto/rand"
+	"crypto/sha1"
+	"encoding/binary"
+	"fmt"
+	"hash"
+	"io"
+	"net"
+	"sync"
+	"time"
+)
+
+// Difference in 100-nanosecond intervals between
+// UUID epoch (October 15, 1582) and Unix epoch (January 1, 1970).
+const epochStart = 122192928000000000
+
+// EpochFunc is the function type used to provide the current time.
+type EpochFunc func() time.Time
+
+// HWAddrFunc is the function type used to provide hardware (MAC) addresses.
+type HWAddrFunc func() (net.HardwareAddr, error)
+
+// DefaultGenerator is the default UUID Generator used by this package.
+var DefaultGenerator Generator = NewGen()
+
+// NewV1 returns a UUID based on the current timestamp and MAC address.
+func NewV1() (UUID, error) {
+	return DefaultGenerator.NewV1()
+}
+
+// NewV3 returns a UUID based on the MD5 hash of the namespace UUID and name.
+func NewV3(ns UUID, name string) UUID {
+	return DefaultGenerator.NewV3(ns, name)
+}
+
+// NewV4 returns a randomly generated UUID.
+func NewV4() (UUID, error) {
+	return DefaultGenerator.NewV4()
+}
+
+// NewV5 returns a UUID based on SHA-1 hash of the namespace UUID and name.
+func NewV5(ns UUID, name string) UUID {
+	return DefaultGenerator.NewV5(ns, name)
+}
+
+// NewV6 returns a k-sortable UUID based on a timestamp and 48 bits of
+// pseudorandom data. The timestamp in a V6 UUID is the same as V1, with the bit
+// order being adjusted to allow the UUID to be k-sortable.
+//
+// This is implemented based on revision 03 of the Peabody UUID draft, and may
+// be subject to change pending further revisions. Until the final specification
+// revision is finished, changes required to implement updates to the spec will
+// not be considered a breaking change. They will happen as a minor version
+// releases until the spec is final.
+func NewV6() (UUID, error) {
+	return DefaultGenerator.NewV6()
+}
+
+// NewV7 returns a k-sortable UUID based on the current millisecond precision
+// UNIX epoch and 74 bits of pseudorandom data. It supports single-node batch generation (multiple UUIDs in the same timestamp) with a Monotonic Random counter.
+//
+// This is implemented based on revision 04 of the Peabody UUID draft, and may
+// be subject to change pending further revisions. Until the final specification
+// revision is finished, changes required to implement updates to the spec will
+// not be considered a breaking change. They will happen as a minor version
+// releases until the spec is final.
+func NewV7() (UUID, error) {
+	return DefaultGenerator.NewV7()
+}
+
+// Generator provides an interface for generating UUIDs.
+type Generator interface {
+	NewV1() (UUID, error)
+	NewV3(ns UUID, name string) UUID
+	NewV4() (UUID, error)
+	NewV5(ns UUID, name string) UUID
+	NewV6() (UUID, error)
+	NewV7() (UUID, error)
+}
+
+// Gen is a reference UUID generator based on the specifications laid out in
+// RFC-4122 and DCE 1.1: Authentication and Security Services. This type
+// satisfies the Generator interface as defined in this package.
+//
+// For consumers who are generating V1 UUIDs, but don't want to expose the MAC
+// address of the node generating the UUIDs, the NewGenWithHWAF() function has been
+// provided as a convenience. See the function's documentation for more info.
+//
+// The authors of this package do not feel that the majority of users will need
+// to obfuscate their MAC address, and so we recommend using NewGen() to create
+// a new generator.
+type Gen struct {
+	clockSequenceOnce sync.Once
+	hardwareAddrOnce  sync.Once
+	storageMutex      sync.Mutex
+
+	rand io.Reader
+
+	epochFunc     EpochFunc
+	hwAddrFunc    HWAddrFunc
+	lastTime      uint64
+	clockSequence uint16
+	hardwareAddr  [6]byte
+}
+
+// GenOption is a function type that can be used to configure a Gen generator.
+type GenOption func(*Gen)
+
+// interface check -- build will fail if *Gen doesn't satisfy Generator
+var _ Generator = (*Gen)(nil)
+
+// NewGen returns a new instance of Gen with some default values set. Most
+// people should use this.
+func NewGen() *Gen {
+	return NewGenWithHWAF(defaultHWAddrFunc)
+}
+
+// NewGenWithHWAF builds a new UUID generator with the HWAddrFunc provided. Most
+// consumers should use NewGen() instead.
+//
+// This is used so that consumers can generate their own MAC addresses, for use
+// in the generated UUIDs, if there is some concern about exposing the physical
+// address of the machine generating the UUID.
+//
+// The Gen generator will only invoke the HWAddrFunc once, and cache that MAC
+// address for all the future UUIDs generated by it. If you'd like to switch the
+// MAC address being used, you'll need to create a new generator using this
+// function.
+func NewGenWithHWAF(hwaf HWAddrFunc) *Gen {
+	return NewGenWithOptions(WithHWAddrFunc(hwaf))
+}
+
+// NewGenWithOptions returns a new instance of Gen with the options provided.
+// Most people should use NewGen() or NewGenWithHWAF() instead.
+//
+// To customize the generator, you can pass in one or more GenOption functions.
+// For example:
+//
+//	gen := NewGenWithOptions(
+//	    WithHWAddrFunc(myHWAddrFunc),
+//	    WithEpochFunc(myEpochFunc),
+//	    WithRandomReader(myRandomReader),
+//	)
+//
+// NewGenWithOptions(WithHWAddrFunc(myHWAddrFunc)) is equivalent to calling
+// NewGenWithHWAF(myHWAddrFunc)
+// NewGenWithOptions() is equivalent to calling NewGen()
+func NewGenWithOptions(opts ...GenOption) *Gen {
+	gen := &Gen{
+		epochFunc:  time.Now,
+		hwAddrFunc: defaultHWAddrFunc,
+		rand:       rand.Reader,
+	}
+
+	for _, opt := range opts {
+		opt(gen)
+	}
+
+	return gen
+}
+
+// WithHWAddrFunc is a GenOption that allows you to provide your own HWAddrFunc
+// function.
+// When this option is nil, the defaultHWAddrFunc is used.
+func WithHWAddrFunc(hwaf HWAddrFunc) GenOption {
+	return func(gen *Gen) {
+		if hwaf == nil {
+			hwaf = defaultHWAddrFunc
+		}
+
+		gen.hwAddrFunc = hwaf
+	}
+}
+
+// WithEpochFunc is a GenOption that allows you to provide your own EpochFunc
+// function.
+// When this option is nil, time.Now is used.
+func WithEpochFunc(epochf EpochFunc) GenOption {
+	return func(gen *Gen) {
+		if epochf == nil {
+			epochf = time.Now
+		}
+
+		gen.epochFunc = epochf
+	}
+}
+
+// WithRandomReader is a GenOption that allows you to provide your own random
+// reader.
+// When this option is nil, the default rand.Reader is used.
+func WithRandomReader(reader io.Reader) GenOption {
+	return func(gen *Gen) {
+		if reader == nil {
+			reader = rand.Reader
+		}
+
+		gen.rand = reader
+	}
+}
+
+// NewV1 returns a UUID based on the current timestamp and MAC address.
+func (g *Gen) NewV1() (UUID, error) {
+	u := UUID{}
+
+	timeNow, clockSeq, err := g.getClockSequence(false)
+	if err != nil {
+		return Nil, err
+	}
+	binary.BigEndian.PutUint32(u[0:], uint32(timeNow))
+	binary.BigEndian.PutUint16(u[4:], uint16(timeNow>>32))
+	binary.BigEndian.PutUint16(u[6:], uint16(timeNow>>48))
+	binary.BigEndian.PutUint16(u[8:], clockSeq)
+
+	hardwareAddr, err := g.getHardwareAddr()
+	if err != nil {
+		return Nil, err
+	}
+	copy(u[10:], hardwareAddr)
+
+	u.SetVersion(V1)
+	u.SetVariant(VariantRFC4122)
+
+	return u, nil
+}
+
+// NewV3 returns a UUID based on the MD5 hash of the namespace UUID and name.
+func (g *Gen) NewV3(ns UUID, name string) UUID {
+	u := newFromHash(md5.New(), ns, name)
+	u.SetVersion(V3)
+	u.SetVariant(VariantRFC4122)
+
+	return u
+}
+
+// NewV4 returns a randomly generated UUID.
+func (g *Gen) NewV4() (UUID, error) {
+	u := UUID{}
+	if _, err := io.ReadFull(g.rand, u[:]); err != nil {
+		return Nil, err
+	}
+	u.SetVersion(V4)
+	u.SetVariant(VariantRFC4122)
+
+	return u, nil
+}
+
+// NewV5 returns a UUID based on SHA-1 hash of the namespace UUID and name.
+func (g *Gen) NewV5(ns UUID, name string) UUID {
+	u := newFromHash(sha1.New(), ns, name)
+	u.SetVersion(V5)
+	u.SetVariant(VariantRFC4122)
+
+	return u
+}
+
+// NewV6 returns a k-sortable UUID based on a timestamp and 48 bits of
+// pseudorandom data. The timestamp in a V6 UUID is the same as V1, with the bit
+// order being adjusted to allow the UUID to be k-sortable.
+//
+// This is implemented based on revision 03 of the Peabody UUID draft, and may
+// be subject to change pending further revisions. Until the final specification
+// revision is finished, changes required to implement updates to the spec will
+// not be considered a breaking change. They will happen as a minor version
+// releases until the spec is final.
+func (g *Gen) NewV6() (UUID, error) {
+	var u UUID
+
+	if _, err := io.ReadFull(g.rand, u[10:]); err != nil {
+		return Nil, err
+	}
+
+	timeNow, clockSeq, err := g.getClockSequence(false)
+	if err != nil {
+		return Nil, err
+	}
+
+	binary.BigEndian.PutUint32(u[0:], uint32(timeNow>>28))   // set time_high
+	binary.BigEndian.PutUint16(u[4:], uint16(timeNow>>12))   // set time_mid
+	binary.BigEndian.PutUint16(u[6:], uint16(timeNow&0xfff)) // set time_low (minus four version bits)
+	binary.BigEndian.PutUint16(u[8:], clockSeq&0x3fff)       // set clk_seq_hi_res (minus two variant bits)
+
+	u.SetVersion(V6)
+	u.SetVariant(VariantRFC4122)
+
+	return u, nil
+}
+
+// getClockSequence returns the epoch and clock sequence for V1,V6 and V7 UUIDs.
+//
+//	When useUnixTSMs is false, it uses the Coordinated Universal Time (UTC) as a count of 100-
+//
+// nanosecond intervals since 00:00:00.00, 15 October 1582 (the date of Gregorian reform to the Christian calendar).
+func (g *Gen) getClockSequence(useUnixTSMs bool) (uint64, uint16, error) {
+	var err error
+	g.clockSequenceOnce.Do(func() {
+		buf := make([]byte, 2)
+		if _, err = io.ReadFull(g.rand, buf); err != nil {
+			return
+		}
+		g.clockSequence = binary.BigEndian.Uint16(buf)
+	})
+	if err != nil {
+		return 0, 0, err
+	}
+
+	g.storageMutex.Lock()
+	defer g.storageMutex.Unlock()
+
+	var timeNow uint64
+	if useUnixTSMs {
+		timeNow = uint64(g.epochFunc().UnixMilli())
+	} else {
+		timeNow = g.getEpoch()
+	}
+	// Clock didn't change since last UUID generation.
+	// Should increase clock sequence.
+	if timeNow <= g.lastTime {
+		g.clockSequence++
+	}
+	g.lastTime = timeNow
+
+	return timeNow, g.clockSequence, nil
+}
+
+// NewV7 returns a k-sortable UUID based on the current millisecond precision
+// UNIX epoch and 74 bits of pseudorandom data.
+//
+// This is implemented based on revision 04 of the Peabody UUID draft, and may
+// be subject to change pending further revisions. Until the final specification
+// revision is finished, changes required to implement updates to the spec will
+// not be considered a breaking change. They will happen as a minor version
+// releases until the spec is final.
+func (g *Gen) NewV7() (UUID, error) {
+	var u UUID
+	/* https://www.ietf.org/archive/id/draft-peabody-dispatch-new-uuid-format-04.html#name-uuid-version-7
+		0                   1                   2                   3
+	    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+	   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+	   |                           unix_ts_ms                          |
+	   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+	   |          unix_ts_ms           |  ver  |       rand_a          |
+	   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+	   |var|                        rand_b                             |
+	   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+	   |                            rand_b                             |
+	   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ */
+
+	ms, clockSeq, err := g.getClockSequence(true)
+	if err != nil {
+		return Nil, err
+	}
+	//UUIDv7 features a 48 bit timestamp. First 32bit (4bytes) represents seconds since 1970, followed by 2 bytes for the ms granularity.
+	u[0] = byte(ms >> 40) //1-6 bytes: big-endian unsigned number of Unix epoch timestamp
+	u[1] = byte(ms >> 32)
+	u[2] = byte(ms >> 24)
+	u[3] = byte(ms >> 16)
+	u[4] = byte(ms >> 8)
+	u[5] = byte(ms)
+
+	//support batching by using a monotonic pseudo-random sequence
+	//The 6th byte contains the version and partially rand_a data.
+	//We will lose the most significant bites from the clockSeq (with SetVersion), but it is ok, we need the least significant that contains the counter to ensure the monotonic property
+	binary.BigEndian.PutUint16(u[6:8], clockSeq) // set rand_a with clock seq which is random and monotonic
+
+	//override first 4bits of u[6].
+	u.SetVersion(V7)
+
+	//set rand_b 64bits of pseudo-random bits (first 2 will be overridden)
+	if _, err = io.ReadFull(g.rand, u[8:16]); err != nil {
+		return Nil, err
+	}
+	//override first 2 bits of byte[8] for the variant
+	u.SetVariant(VariantRFC4122)
+
+	return u, nil
+}
+
+// Returns the hardware address.
+func (g *Gen) getHardwareAddr() ([]byte, error) {
+	var err error
+	g.hardwareAddrOnce.Do(func() {
+		var hwAddr net.HardwareAddr
+		if hwAddr, err = g.hwAddrFunc(); err == nil {
+			copy(g.hardwareAddr[:], hwAddr)
+			return
+		}
+
+		// Initialize hardwareAddr randomly in case
+		// of real network interfaces absence.
+		if _, err = io.ReadFull(g.rand, g.hardwareAddr[:]); err != nil {
+			return
+		}
+		// Set multicast bit as recommended by RFC-4122
+		g.hardwareAddr[0] |= 0x01
+	})
+	if err != nil {
+		return []byte{}, err
+	}
+	return g.hardwareAddr[:], nil
+}
+
+// Returns the difference between UUID epoch (October 15, 1582)
+// and current time in 100-nanosecond intervals.
+func (g *Gen) getEpoch() uint64 {
+	return epochStart + uint64(g.epochFunc().UnixNano()/100)
+}
+
+// Returns the UUID based on the hashing of the namespace UUID and name.
+func newFromHash(h hash.Hash, ns UUID, name string) UUID {
+	u := UUID{}
+	h.Write(ns[:])
+	h.Write([]byte(name))
+	copy(u[:], h.Sum(nil))
+
+	return u
+}
+
+var netInterfaces = net.Interfaces
+
+// Returns the hardware address.
+func defaultHWAddrFunc() (net.HardwareAddr, error) {
+	ifaces, err := netInterfaces()
+	if err != nil {
+		return []byte{}, err
+	}
+	for _, iface := range ifaces {
+		if len(iface.HardwareAddr) >= 6 {
+			return iface.HardwareAddr, nil
+		}
+	}
+	return []byte{}, fmt.Errorf("uuid: no HW address found")
+}

vendor/github.com/gofrs/uuid/sql.go

@@ -0,0 +1,116 @@
+// Copyright (C) 2013-2018 by Maxim Bublis <b@codemonkey.ru>
+//
+// Permission is hereby granted, free of charge, to any person obtaining
+// a copy of this software and associated documentation files (the
+// "Software"), to deal in the Software without restriction, including
+// without limitation the rights to use, copy, modify, merge, publish,
+// distribute, sublicense, and/or sell copies of the Software, and to
+// permit persons to whom the Software is furnished to do so, subject to
+// the following conditions:
+//
+// The above copyright notice and this permission notice shall be
+// included in all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+// LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+// OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+// WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+package uuid
+
+import (
+	"database/sql"
+	"database/sql/driver"
+	"fmt"
+)
+
+var _ driver.Valuer = UUID{}
+var _ sql.Scanner = (*UUID)(nil)
+
+// Value implements the driver.Valuer interface.
+func (u UUID) Value() (driver.Value, error) {
+	return u.String(), nil
+}
+
+// Scan implements the sql.Scanner interface.
+// A 16-byte slice will be handled by UnmarshalBinary, while
+// a longer byte slice or a string will be handled by UnmarshalText.
+func (u *UUID) Scan(src interface{}) error {
+	switch src := src.(type) {
+	case UUID: // support gorm convert from UUID to NullUUID
+		*u = src
+		return nil
+
+	case []byte:
+		if len(src) == Size {
+			return u.UnmarshalBinary(src)
+		}
+		return u.UnmarshalText(src)
+
+	case string:
+		uu, err := FromString(src)
+		*u = uu
+		return err
+	}
+
+	return fmt.Errorf("uuid: cannot convert %T to UUID", src)
+}
+
+// NullUUID can be used with the standard sql package to represent a
+// UUID value that can be NULL in the database.
+type NullUUID struct {
+	UUID  UUID
+	Valid bool
+}
+
+// Value implements the driver.Valuer interface.
+func (u NullUUID) Value() (driver.Value, error) {
+	if !u.Valid {
+		return nil, nil
+	}
+	// Delegate to UUID Value function
+	return u.UUID.Value()
+}
+
+// Scan implements the sql.Scanner interface.
+func (u *NullUUID) Scan(src interface{}) error {
+	if src == nil {
+		u.UUID, u.Valid = Nil, false
+		return nil
+	}
+
+	// Delegate to UUID Scan function
+	u.Valid = true
+	return u.UUID.Scan(src)
+}
+
+var nullJSON = []byte("null")
+
+// MarshalJSON marshals the NullUUID as null or the nested UUID
+func (u NullUUID) MarshalJSON() ([]byte, error) {
+	if !u.Valid {
+		return nullJSON, nil
+	}
+	var buf [38]byte
+	buf[0] = '"'
+	encodeCanonical(buf[1:37], u.UUID)
+	buf[37] = '"'
+	return buf[:], nil
+}
+
+// UnmarshalJSON unmarshals a NullUUID
+func (u *NullUUID) UnmarshalJSON(b []byte) error {
+	if string(b) == "null" {
+		u.UUID, u.Valid = Nil, false
+		return nil
+	}
+	if n := len(b); n >= 2 && b[0] == '"' {
+		b = b[1 : n-1]
+	}
+	err := u.UUID.UnmarshalText(b)
+	u.Valid = (err == nil)
+	return err
+}

vendor/github.com/gofrs/uuid/uuid.go

@@ -0,0 +1,285 @@
+// Copyright (C) 2013-2018 by Maxim Bublis <b@codemonkey.ru>
+//
+// Permission is hereby granted, free of charge, to any person obtaining
+// a copy of this software and associated documentation files (the
+// "Software"), to deal in the Software without restriction, including
+// without limitation the rights to use, copy, modify, merge, publish,
+// distribute, sublicense, and/or sell copies of the Software, and to
+// permit persons to whom the Software is furnished to do so, subject to
+// the following conditions:
+//
+// The above copyright notice and this permission notice shall be
+// included in all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+// LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+// OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+// WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+// Package uuid provides implementations of the Universally Unique Identifier
+// (UUID), as specified in RFC-4122 and the Peabody RFC Draft (revision 03).
+//
+// RFC-4122[1] provides the specification for versions 1, 3, 4, and 5. The
+// Peabody UUID RFC Draft[2] provides the specification for the new k-sortable
+// UUIDs, versions 6 and 7.
+//
+// DCE 1.1[3] provides the specification for version 2, but version 2 support
+// was removed from this package in v4 due to some concerns with the
+// specification itself. Reading the spec, it seems that it would result in
+// generating UUIDs that aren't very unique. In having read the spec it seemed
+// that our implementation did not meet the spec. It also seems to be at-odds
+// with RFC 4122, meaning we would need quite a bit of special code to support
+// it. Lastly, there were no Version 2 implementations that we could find to
+// ensure we were understanding the specification correctly.
+//
+// [1] https://tools.ietf.org/html/rfc4122
+// [2] https://datatracker.ietf.org/doc/html/draft-peabody-dispatch-new-uuid-format-03
+// [3] http://pubs.opengroup.org/onlinepubs/9696989899/chap5.htm#tagcjh_08_02_01_01
+package uuid
+
+import (
+	"encoding/binary"
+	"encoding/hex"
+	"fmt"
+	"time"
+)
+
+// Size of a UUID in bytes.
+const Size = 16
+
+// UUID is an array type to represent the value of a UUID, as defined in RFC-4122.
+type UUID [Size]byte
+
+// UUID versions.
+const (
+	_  byte = iota
+	V1      // Version 1 (date-time and MAC address)
+	_       // Version 2 (date-time and MAC address, DCE security version) [removed]
+	V3      // Version 3 (namespace name-based)
+	V4      // Version 4 (random)
+	V5      // Version 5 (namespace name-based)
+	V6      // Version 6 (k-sortable timestamp and random data, field-compatible with v1) [peabody draft]
+	V7      // Version 7 (k-sortable timestamp and random data) [peabody draft]
+	_       // Version 8 (k-sortable timestamp, meant for custom implementations) [peabody draft] [not implemented]
+)
+
+// UUID layout variants.
+const (
+	VariantNCS byte = iota
+	VariantRFC4122
+	VariantMicrosoft
+	VariantFuture
+)
+
+// UUID DCE domains.
+const (
+	DomainPerson = iota
+	DomainGroup
+	DomainOrg
+)
+
+// Timestamp is the count of 100-nanosecond intervals since 00:00:00.00,
+// 15 October 1582 within a V1 UUID. This type has no meaning for other
+// UUID versions since they don't have an embedded timestamp.
+type Timestamp uint64
+
+const _100nsPerSecond = 10000000
+
+// Time returns the UTC time.Time representation of a Timestamp
+func (t Timestamp) Time() (time.Time, error) {
+	secs := uint64(t) / _100nsPerSecond
+	nsecs := 100 * (uint64(t) % _100nsPerSecond)
+
+	return time.Unix(int64(secs)-(epochStart/_100nsPerSecond), int64(nsecs)), nil
+}
+
+// TimestampFromV1 returns the Timestamp embedded within a V1 UUID.
+// Returns an error if the UUID is any version other than 1.
+func TimestampFromV1(u UUID) (Timestamp, error) {
+	if u.Version() != 1 {
+		err := fmt.Errorf("uuid: %s is version %d, not version 1", u, u.Version())
+		return 0, err
+	}
+
+	low := binary.BigEndian.Uint32(u[0:4])
+	mid := binary.BigEndian.Uint16(u[4:6])
+	hi := binary.BigEndian.Uint16(u[6:8]) & 0xfff
+
+	return Timestamp(uint64(low) + (uint64(mid) << 32) + (uint64(hi) << 48)), nil
+}
+
+// TimestampFromV6 returns the Timestamp embedded within a V6 UUID. This
+// function returns an error if the UUID is any version other than 6.
+//
+// This is implemented based on revision 03 of the Peabody UUID draft, and may
+// be subject to change pending further revisions. Until the final specification
+// revision is finished, changes required to implement updates to the spec will
+// not be considered a breaking change. They will happen as a minor version
+// releases until the spec is final.
+func TimestampFromV6(u UUID) (Timestamp, error) {
+	if u.Version() != 6 {
+		return 0, fmt.Errorf("uuid: %s is version %d, not version 6", u, u.Version())
+	}
+
+	hi := binary.BigEndian.Uint32(u[0:4])
+	mid := binary.BigEndian.Uint16(u[4:6])
+	low := binary.BigEndian.Uint16(u[6:8]) & 0xfff
+
+	return Timestamp(uint64(low) + (uint64(mid) << 12) + (uint64(hi) << 28)), nil
+}
+
+// Nil is the nil UUID, as specified in RFC-4122, that has all 128 bits set to
+// zero.
+var Nil = UUID{}
+
+// Predefined namespace UUIDs.
+var (
+	NamespaceDNS  = Must(FromString("6ba7b810-9dad-11d1-80b4-00c04fd430c8"))
+	NamespaceURL  = Must(FromString("6ba7b811-9dad-11d1-80b4-00c04fd430c8"))
+	NamespaceOID  = Must(FromString("6ba7b812-9dad-11d1-80b4-00c04fd430c8"))
+	NamespaceX500 = Must(FromString("6ba7b814-9dad-11d1-80b4-00c04fd430c8"))
+)
+
+// IsNil returns if the UUID is equal to the nil UUID
+func (u UUID) IsNil() bool {
+	return u == Nil
+}
+
+// Version returns the algorithm version used to generate the UUID.
+func (u UUID) Version() byte {
+	return u[6] >> 4
+}
+
+// Variant returns the UUID layout variant.
+func (u UUID) Variant() byte {
+	switch {
+	case (u[8] >> 7) == 0x00:
+		return VariantNCS
+	case (u[8] >> 6) == 0x02:
+		return VariantRFC4122
+	case (u[8] >> 5) == 0x06:
+		return VariantMicrosoft
+	case (u[8] >> 5) == 0x07:
+		fallthrough
+	default:
+		return VariantFuture
+	}
+}
+
+// Bytes returns a byte slice representation of the UUID.
+func (u UUID) Bytes() []byte {
+	return u[:]
+}
+
+// encodeCanonical encodes the canonical RFC-4122 form of UUID u into the
+// first 36 bytes dst.
+func encodeCanonical(dst []byte, u UUID) {
+	const hextable = "0123456789abcdef"
+	dst[8] = '-'
+	dst[13] = '-'
+	dst[18] = '-'
+	dst[23] = '-'
+	for i, x := range [16]byte{
+		0, 2, 4, 6,
+		9, 11,
+		14, 16,
+		19, 21,
+		24, 26, 28, 30, 32, 34,
+	} {
+		c := u[i]
+		dst[x] = hextable[c>>4]
+		dst[x+1] = hextable[c&0x0f]
+	}
+}
+
+// String returns a canonical RFC-4122 string representation of the UUID:
+// xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx.
+func (u UUID) String() string {
+	var buf [36]byte
+	encodeCanonical(buf[:], u)
+	return string(buf[:])
+}
+
+// Format implements fmt.Formatter for UUID values.
+//
+// The behavior is as follows:
+// The 'x' and 'X' verbs output only the hex digits of the UUID, using a-f for 'x' and A-F for 'X'.
+// The 'v', '+v', 's' and 'q' verbs return the canonical RFC-4122 string representation.
+// The 'S' verb returns the RFC-4122 format, but with capital hex digits.
+// The '#v' verb returns the "Go syntax" representation, which is a 16 byte array initializer.
+// All other verbs not handled directly by the fmt package (like '%p') are unsupported and will return
+// "%!verb(uuid.UUID=value)" as recommended by the fmt package.
+func (u UUID) Format(f fmt.State, c rune) {
+	if c == 'v' && f.Flag('#') {
+		fmt.Fprintf(f, "%#v", [Size]byte(u))
+		return
+	}
+	switch c {
+	case 'x', 'X':
+		b := make([]byte, 32)
+		hex.Encode(b, u[:])
+		if c == 'X' {
+			toUpperHex(b)
+		}
+		_, _ = f.Write(b)
+	case 'v', 's', 'S':
+		b, _ := u.MarshalText()
+		if c == 'S' {
+			toUpperHex(b)
+		}
+		_, _ = f.Write(b)
+	case 'q':
+		b := make([]byte, 38)
+		b[0] = '"'
+		encodeCanonical(b[1:], u)
+		b[37] = '"'
+		_, _ = f.Write(b)
+	default:
+		// invalid/unsupported format verb
+		fmt.Fprintf(f, "%%!%c(uuid.UUID=%s)", c, u.String())
+	}
+}
+
+func toUpperHex(b []byte) {
+	for i, c := range b {
+		if 'a' <= c && c <= 'f' {
+			b[i] = c - ('a' - 'A')
+		}
+	}
+}
+
+// SetVersion sets the version bits.
+func (u *UUID) SetVersion(v byte) {
+	u[6] = (u[6] & 0x0f) | (v << 4)
+}
+
+// SetVariant sets the variant bits.
+func (u *UUID) SetVariant(v byte) {
+	switch v {
+	case VariantNCS:
+		u[8] = (u[8]&(0xff>>1) | (0x00 << 7))
+	case VariantRFC4122:
+		u[8] = (u[8]&(0xff>>2) | (0x02 << 6))
+	case VariantMicrosoft:
+		u[8] = (u[8]&(0xff>>3) | (0x06 << 5))
+	case VariantFuture:
+		fallthrough
+	default:
+		u[8] = (u[8]&(0xff>>3) | (0x07 << 5))
+	}
+}
+
+// Must is a helper that wraps a call to a function returning (UUID, error)
+// and panics if the error is non-nil. It is intended for use in variable
+// initializations such as
+//
+//	var packageUUID = uuid.Must(uuid.FromString("123e4567-e89b-12d3-a456-426655440000"))
+func Must(u UUID, err error) UUID {
+	if err != nil {
+		panic(err)
+	}
+	return u
+}