status-go/vendor/github.com/anacrolix/chansync/flag.go

80 lines
1.1 KiB
Go

package chansync
import (
"sync"
"github.com/anacrolix/chansync/events"
)
// Flag wraps a boolean value that starts as false (off). You can wait for it to be on or off, and
// set the value as needed.
type Flag struct {
mu sync.Mutex
on chan struct{}
off chan struct{}
state bool
inited bool
}
func (me *Flag) Bool() bool {
me.mu.Lock()
defer me.mu.Unlock()
return me.state
}
func (me *Flag) On() events.Active {
me.mu.Lock()
defer me.mu.Unlock()
me.init()
return me.on
}
func (me *Flag) Off() events.Active {
me.mu.Lock()
defer me.mu.Unlock()
me.init()
return me.off
}
func (me *Flag) init() {
if me.inited {
return
}
me.on = make(chan struct{})
me.off = make(chan struct{})
close(me.off)
me.inited = true
}
func (me *Flag) SetBool(b bool) {
if b {
me.Set()
} else {
me.Clear()
}
}
func (me *Flag) Set() {
me.mu.Lock()
defer me.mu.Unlock()
me.init()
if me.state {
return
}
me.state = true
close(me.on)
me.off = make(chan struct{})
}
func (me *Flag) Clear() {
me.mu.Lock()
defer me.mu.Unlock()
me.init()
if !me.state {
return
}
me.state = false
close(me.off)
me.on = make(chan struct{})
}