func (r *raftState) getLastIndex() uint64 {
	return max(r.getLastLogIndex(), r.getLastSnapshotIndex())
}
getLastIndex returns the last index in stable storage.
Either from the last log or from the last snapshot
package raft
import (
	"sync/atomic"
)
type RaftState uint32
const (
	Follower RaftState = iota
	Candidate
	Leader
	Shutdown
)
func (s RaftState) String() string {
	switch s {
	case Follower:
		return "Follower"
	case Candidate:
		return "Candidate"
	case Leader:
		return "Leader"
	case Shutdown:
		return "Shutdown"
	default:
		return "Unknown"
	}
}
type raftState struct {
	currentTerm uint64
	LastLogIndex uint64
	LastLogTerm  uint64
	commitIndex uint64
	lastApplied uint64
	lastSnapshotIndex uint64
	lastSnapshotTerm  uint64
	runningRoutines int32
	state RaftState
}
func (r *raftState) getState() RaftState {
	stateAddr := (*uint32)(&r.state)
	return RaftState(atomic.LoadUint32(stateAddr))
}
func (r *raftState) setState(s RaftState) {
	stateAddr := (*uint32)(&r.state)
	atomic.StoreUint32(stateAddr, uint32(s))
}
func (r *raftState) getCurrentTerm() uint64 {
	return atomic.LoadUint64(&r.currentTerm)
}
func (r *raftState) setCurrentTerm(term uint64) {
	atomic.StoreUint64(&r.currentTerm, term)
}
func (r *raftState) getLastLogIndex() uint64 {
	return atomic.LoadUint64(&r.LastLogIndex)
}
func (r *raftState) setLastLogIndex(term uint64) {
	atomic.StoreUint64(&r.LastLogIndex, term)
}
func (r *raftState) getLastLogTerm() uint64 {
	return atomic.LoadUint64(&r.LastLogTerm)
}
func (r *raftState) setLastLogTerm(term uint64) {
	atomic.StoreUint64(&r.LastLogTerm, term)
}
func (r *raftState) getCommitIndex() uint64 {
	return atomic.LoadUint64(&r.commitIndex)
}
func (r *raftState) setCommitIndex(term uint64) {
	atomic.StoreUint64(&r.commitIndex, term)
}
func (r *raftState) getLastApplied() uint64 {
	return atomic.LoadUint64(&r.lastApplied)
}
func (r *raftState) setLastApplied(term uint64) {
	atomic.StoreUint64(&r.lastApplied, term)
}
func (r *raftState) getLastSnapshotIndex() uint64 {
	return atomic.LoadUint64(&r.lastSnapshotIndex)
}
func (r *raftState) setLastSnapshotIndex(term uint64) {
	atomic.StoreUint64(&r.lastSnapshotIndex, term)
}
func (r *raftState) getLastSnapshotTerm() uint64 {
	return atomic.LoadUint64(&r.lastSnapshotTerm)
}
func (r *raftState) setLastSnapshotTerm(term uint64) {
	atomic.StoreUint64(&r.lastSnapshotTerm, term)
}
func (r *raftState) incrRoutines() {
	atomic.AddInt32(&r.runningRoutines, 1)
}
func (r *raftState) decrRoutines() {
	atomic.AddInt32(&r.runningRoutines, -1)
}
func (r *raftState) getRoutines() int32 {
	return atomic.LoadInt32(&r.runningRoutines)
}
func (r *raftState) goFunc(f func()) {
	r.incrRoutines()
	go func() {
		defer r.decrRoutines()
		f()
	}()
}