update

idGenerator/id_generator.go

@@ -0,0 +1,118 @@
+package idgenerator
+
+import (
+	"fmt"
+	"math"
+	"time"
+
+	_ "unsafe"
+)
+
+// 时间段开始时间 2022-01-01
+const startTimeStamp = 1640966400
+
+const (
+	MachineIdBits  = uint(8)                              //机器id所占的位数
+	SequenceBits   = uint(12)                             //序列所占的位数
+	MachineIdMax   = int64(-1 ^ (-1 << MachineIdBits))    //支持的最大机器id数量
+	SequenceMask   = uint64(-1 ^ (-1 << SequenceBits))    //
+	MachineIdShift = uint64(SequenceBits)                 //机器id左移位数
+	TimestampShift = uint64(SequenceBits + MachineIdBits) //时间戳左移位数
+)
+
+type TimePrecision int
+
+const (
+	Second TimePrecision = iota // 秒
+	Minute                      // 分
+	Day                         // 日
+)
+
+type Config struct {
+	Machine   int
+	TimeScope TimePrecision
+}
+
+type Generator struct {
+	machine   uint64
+	timeScope TimePrecision // 时间段精度
+	timestamp uint64        // 上次生成时间
+	sequence  uint64        // 上次使用序列
+}
+
+type Id struct {
+	machine   uint64 // 机器标识
+	Scope     int    // 时间精度
+	Timestamp uint64 // 生成时间
+	Sequence  uint64 // 标识序列
+}
+
+func New(cfg Config) *Generator {
+	return &Generator{
+		machine:   uint64(cfg.Machine),
+		timeScope: cfg.TimeScope,
+	}
+}
+
+func (g *Generator) Next() Id {
+
+	now := currentTimestamp()
+
+	if g.timestamp == now && g.sequence == 0 {
+		fmt.Println(time.Now().Format("2006-01-02 15:04:05.000"), "下一个时间点")
+		for now <= g.timestamp {
+			// runtime.Gosched()
+			now = currentTimestamp()
+		}
+	}
+
+	g.timestamp = now                            // 标识生成时间
+	g.sequence = (g.sequence + 1) & SequenceMask // 生成下一序列，超过最大值时返回零
+
+	return Id{
+		machine:   g.machine,
+		Timestamp: g.timestamp,
+		Sequence:  g.sequence,
+	}
+}
+
+func (i Id) Id() uint64 {
+	return i.Timestamp<<TimestampShift | i.machine<<MachineIdShift | i.Sequence
+}
+
+func (i Id) genCheck() uint64 {
+	return math.MaxUint64
+}
+
+func (i Id) String() string {
+	return fmt.Sprintf("Time:%d scope: %d Machine: %d Ser:%06d id:%d", i.Timestamp, i.Scope, i.machine, i.Sequence, i.Id())
+}
+
+func (g *Generator) NextId() uint64 {
+	return g.Next().Id()
+}
+
+func (g *Generator) Batch(num int) []uint64 {
+	ret := make([]uint64, num)
+
+	for i := 0; i < num; i++ {
+		ret[i] = g.NextId()
+	}
+
+	return ret
+}
+
+func Decode(id uint64) Id {
+	return Id{}
+}
+
+func Verify(id uint64) bool {
+	return false
+}
+
+func currentTimestamp() uint64 {
+	return uint64(time.Now().Unix() - startTimeStamp)
+}
+
+//go:linkname runtimeNano runtime.nanotime
+func runtimeNano() int64