diff options
Diffstat (limited to 'vendor/github.com/dexon-foundation/dexon-consensus-core/common/event.go')
-rw-r--r-- | vendor/github.com/dexon-foundation/dexon-consensus-core/common/event.go | 102 |
1 files changed, 102 insertions, 0 deletions
diff --git a/vendor/github.com/dexon-foundation/dexon-consensus-core/common/event.go b/vendor/github.com/dexon-foundation/dexon-consensus-core/common/event.go new file mode 100644 index 000000000..dab34a5f6 --- /dev/null +++ b/vendor/github.com/dexon-foundation/dexon-consensus-core/common/event.go @@ -0,0 +1,102 @@ +// Copyright 2018 The dexon-consensus-core Authors +// This file is part of the dexon-consensus-core library. +// +// The dexon-consensus-core 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 dexon-consensus-core 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 dexon-consensus-core library. If not, see +// <http://www.gnu.org/licenses/>. + +package common + +import ( + "container/heap" + "sync" + "time" +) + +type timeEventFn func(time.Time) + +type timeEvent struct { + t time.Time + fn timeEventFn +} + +// timeEvents implements a Min-Heap structure. +type timeEvents []timeEvent + +func (h timeEvents) Len() int { return len(h) } +func (h timeEvents) Less(i, j int) bool { return h[i].t.Before(h[j].t) } +func (h timeEvents) Swap(i, j int) { h[i], h[j] = h[j], h[i] } +func (h *timeEvents) Push(x interface{}) { + *h = append(*h, x.(timeEvent)) +} +func (h *timeEvents) Pop() interface{} { + old := *h + n := len(old) + x := old[n-1] + *h = old[0 : n-1] + return x +} + +// Event implements the Observer pattern. +type Event struct { + timeEvents timeEvents + timeEventsLock sync.Mutex +} + +// NewEvent creates a new event instance. +func NewEvent() *Event { + te := timeEvents{} + heap.Init(&te) + return &Event{ + timeEvents: te, + } +} + +// RegisterTime to get notified on and after specific time. +func (e *Event) RegisterTime(t time.Time, fn timeEventFn) { + e.timeEventsLock.Lock() + defer e.timeEventsLock.Unlock() + heap.Push(&e.timeEvents, timeEvent{ + t: t, + fn: fn, + }) +} + +// NotifyTime and trigger function callback. +func (e *Event) NotifyTime(t time.Time) { + fns := func() (fns []timeEventFn) { + e.timeEventsLock.Lock() + defer e.timeEventsLock.Unlock() + if len(e.timeEvents) == 0 { + return + } + for !t.Before(e.timeEvents[0].t) { + te := heap.Pop(&e.timeEvents).(timeEvent) + fns = append(fns, te.fn) + if len(e.timeEvents) == 0 { + return + } + } + return + }() + for _, fn := range fns { + fn(t) + } +} + +// Reset clears all pending event +func (e *Event) Reset() { + e.timeEventsLock.Lock() + defer e.timeEventsLock.Unlock() + e.timeEvents = timeEvents{} +} |