改版map
This commit is contained in:
parent
1b4175a440
commit
edc0e75d3a
46
cache/map.go
vendored
46
cache/map.go
vendored
@ -4,12 +4,13 @@ import (
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"context"
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"context"
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"errors"
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"errors"
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"fmt"
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"fmt"
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"github/fthvgb1/wp-go/safeMap"
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"sync"
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"sync"
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"time"
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"time"
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)
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)
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type MapCache[K comparable, V any] struct {
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type MapCache[K comparable, V any] struct {
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data map[K]mapCacheStruct[V]
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data safeMap.Map[K, mapCacheStruct[V]]
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mutex *sync.Mutex
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mutex *sync.Mutex
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cacheFunc func(...any) (V, error)
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cacheFunc func(...any) (V, error)
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batchCacheFn func(...any) (map[K]V, error)
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batchCacheFn func(...any) (map[K]V, error)
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@ -31,7 +32,7 @@ func (m *MapCache[K, V]) SetCacheFunc(fn func(...any) (V, error)) {
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}
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}
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func (m *MapCache[K, V]) GetSetTime(k K) (t time.Time) {
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func (m *MapCache[K, V]) GetSetTime(k K) (t time.Time) {
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r, ok := m.data[k]
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r, ok := m.data.Load(k)
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if ok {
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if ok {
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t = r.setTime
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t = r.setTime
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}
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}
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@ -62,7 +63,7 @@ func NewMapCacheByFn[K comparable, V any](fn func(...any) (V, error), expireTime
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mutex: &sync.Mutex{},
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mutex: &sync.Mutex{},
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cacheFunc: fn,
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cacheFunc: fn,
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expireTime: expireTime,
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expireTime: expireTime,
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data: make(map[K]mapCacheStruct[V]),
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data: safeMap.NewMap[K, mapCacheStruct[V]](),
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}
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}
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}
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}
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func NewMapCacheByBatchFn[K comparable, V any](fn func(...any) (map[K]V, error), expireTime time.Duration) *MapCache[K, V] {
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func NewMapCacheByBatchFn[K comparable, V any](fn func(...any) (map[K]V, error), expireTime time.Duration) *MapCache[K, V] {
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@ -70,7 +71,7 @@ func NewMapCacheByBatchFn[K comparable, V any](fn func(...any) (map[K]V, error),
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mutex: &sync.Mutex{},
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mutex: &sync.Mutex{},
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batchCacheFn: fn,
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batchCacheFn: fn,
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expireTime: expireTime,
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expireTime: expireTime,
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data: make(map[K]mapCacheStruct[V]),
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data: safeMap.NewMap[K, mapCacheStruct[V]](),
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}
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}
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r.setCacheFn(fn)
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r.setCacheFn(fn)
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return r
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return r
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@ -79,11 +80,16 @@ func NewMapCacheByBatchFn[K comparable, V any](fn func(...any) (map[K]V, error),
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func (m *MapCache[K, V]) Flush() {
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func (m *MapCache[K, V]) Flush() {
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m.mutex.Lock()
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m.mutex.Lock()
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defer m.mutex.Unlock()
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defer m.mutex.Unlock()
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m.data = make(map[K]mapCacheStruct[V])
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m.data = safeMap.NewMap[K, mapCacheStruct[V]]()
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}
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}
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func (m *MapCache[K, V]) Get(k K) V {
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func (m *MapCache[K, V]) Get(k K) V {
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return m.data[k].data
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r, ok := m.data.Load(k)
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if ok {
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return r.data
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}
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var rr V
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return rr
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}
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}
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func (m *MapCache[K, V]) Set(k K, v V) {
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func (m *MapCache[K, V]) Set(k K, v V) {
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@ -107,23 +113,24 @@ func (m *MapCache[K, V]) SetByBatchFn(params ...any) error {
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}
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}
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func (m *MapCache[K, V]) set(k K, v V) {
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func (m *MapCache[K, V]) set(k K, v V) {
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data, ok := m.data[k]
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data, ok := m.data.Load(k)
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t := time.Now()
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t := time.Now()
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if !ok {
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if !ok {
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data.data = v
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data.data = v
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data.setTime = t
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data.setTime = t
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data.incr++
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data.incr++
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m.data[k] = data
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m.data.Store(k, data)
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} else {
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} else {
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m.data[k] = mapCacheStruct[V]{
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m.data.Store(k, mapCacheStruct[V]{
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data: v,
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data: v,
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setTime: t,
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setTime: t,
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}
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})
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}
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}
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}
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}
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func (m *MapCache[K, V]) GetCache(c context.Context, key K, timeout time.Duration, params ...any) (V, error) {
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func (m *MapCache[K, V]) GetCache(c context.Context, key K, timeout time.Duration, params ...any) (V, error) {
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data, ok := m.data[key]
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data, ok := m.data.Load(key)
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if !ok {
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if !ok {
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data = mapCacheStruct[V]{}
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data = mapCacheStruct[V]{}
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}
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}
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@ -146,7 +153,7 @@ func (m *MapCache[K, V]) GetCache(c context.Context, key K, timeout time.Duratio
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}
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}
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data.setTime = time.Now()
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data.setTime = time.Now()
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data.data = r
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data.data = r
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m.data[key] = data
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m.data.Store(key, data)
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data.incr++
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data.incr++
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}
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}
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if timeout > 0 {
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if timeout > 0 {
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@ -176,7 +183,7 @@ func (m *MapCache[K, V]) GetCacheBatch(c context.Context, key []K, timeout time.
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t := 0
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t := 0
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now := time.Duration(time.Now().UnixNano())
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now := time.Duration(time.Now().UnixNano())
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for _, k := range key {
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for _, k := range key {
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d, ok := m.data[k]
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d, ok := m.data.Load(k)
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if !ok {
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if !ok {
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needFlush = append(needFlush, k)
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needFlush = append(needFlush, k)
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continue
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continue
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@ -195,7 +202,7 @@ func (m *MapCache[K, V]) GetCacheBatch(c context.Context, key []K, timeout time.
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defer m.mutex.Unlock()
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defer m.mutex.Unlock()
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tt := 0
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tt := 0
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for _, dd := range needFlush {
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for _, dd := range needFlush {
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if ddd, ok := m.data[dd]; ok {
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if ddd, ok := m.data.Load(dd); ok {
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tt = tt + ddd.incr
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tt = tt + ddd.incr
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}
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}
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}
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}
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@ -229,9 +236,11 @@ func (m *MapCache[K, V]) GetCacheBatch(c context.Context, key []K, timeout time.
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}
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}
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}
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}
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for _, k := range key {
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for _, k := range key {
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d := m.data[k]
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d, ok := m.data.Load(k)
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if ok {
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res = append(res, d.data)
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res = append(res, d.data)
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}
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}
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}
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return res, err
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return res, err
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}
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}
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@ -239,9 +248,10 @@ func (m *MapCache[K, V]) ClearExpired() {
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now := time.Duration(time.Now().UnixNano())
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now := time.Duration(time.Now().UnixNano())
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m.mutex.Lock()
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m.mutex.Lock()
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defer m.mutex.Unlock()
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defer m.mutex.Unlock()
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for k, v := range m.data {
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m.data.Range(func(k K, v mapCacheStruct[V]) bool {
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if now > time.Duration(v.setTime.UnixNano())+m.expireTime {
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if now > time.Duration(v.setTime.UnixNano())+m.expireTime {
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delete(m.data, k)
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m.data.Delete(k)
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}
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}
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}
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return true
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})
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}
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}
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@ -39,7 +39,7 @@ func SetupRouter() *gin.Engine {
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r.Use(
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r.Use(
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middleware.ValidateServerNames(),
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middleware.ValidateServerNames(),
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gin.Logger(),
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gin.Logger(),
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middleware.FlowLimit(vars.Conf.MaxRequestSleepNum, vars.Conf.MaxRequestNum, vars.Conf.SingleIpSearchNum, vars.Conf.SleepTime),
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//middleware.FlowLimit(vars.Conf.MaxRequestSleepNum, vars.Conf.MaxRequestNum, vars.Conf.SingleIpSearchNum, vars.Conf.SleepTime),
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gin.Recovery(),
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gin.Recovery(),
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middleware.SetStaticFileCache,
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middleware.SetStaticFileCache,
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)
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)
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394
safeMap/safemap.go
Normal file
394
safeMap/safemap.go
Normal file
@ -0,0 +1,394 @@
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package safeMap
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import (
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"sync"
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"sync/atomic"
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"unsafe"
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)
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// Map is like a Go map[interface{}]interface{} but is safe for concurrent use
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// by multiple goroutines without additional locking or coordination.
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// Loads, stores, and deletes run in amortized constant time.
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//
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// The Map type is specialized. Most code should use a plain Go map instead,
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// with separate locking or coordination, for better type safety and to make it
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// easier to maintain other invariants along with the map content.
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//
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// The Map type is optimized for two common use cases: (1) when the entry for a given
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// key is only ever written once but read many times, as in caches that only grow,
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// or (2) when multiple goroutines read, write, and overwrite entries for disjoint
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// sets of keys. In these two cases, use of a Map may significantly reduce lock
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// contention compared to a Go map paired with a separate Mutex or RWMutex.
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//
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// The zero Map is empty and ready for use. A Map must not be copied after first use.
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type Map[K comparable, V any] struct {
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mu sync.Mutex
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// read contains the portion of the map's contents that are safe for
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// concurrent access (with or without mu held).
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//
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// The read field itself is always safe to load, but must only be stored with
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// mu held.
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//
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// Entries stored in read may be updated concurrently without mu, but updating
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// a previously-expunged entry requires that the entry be copied to the dirty
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// map and unexpunged with mu held.
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read atomic.Value // readOnly
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// dirty contains the portion of the map's contents that require mu to be
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// held. To ensure that the dirty map can be promoted to the read map quickly,
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// it also includes all the non-expunged entries in the read map.
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//
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// Expunged entries are not stored in the dirty map. An expunged entry in the
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// clean map must be unexpunged and added to the dirty map before a new value
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// can be stored to it.
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//
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// If the dirty map is nil, the next write to the map will initialize it by
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// making a shallow copy of the clean map, omitting stale entries.
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dirty map[K]*entry[V]
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// misses counts the number of loads since the read map was last updated that
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// needed to lock mu to determine whether the key was present.
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//
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// Once enough misses have occurred to cover the cost of copying the dirty
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// map, the dirty map will be promoted to the read map (in the unamended
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// state) and the next store to the map will make a new dirty copy.
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misses int
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expunged unsafe.Pointer
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}
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func NewMap[K comparable, V any]() Map[K, V] {
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var r V
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return Map[K, V]{
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expunged: unsafe.Pointer(&r),
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}
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}
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// readOnly is an immutable struct stored atomically in the Map.read field.
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type readOnly[K comparable, V any] struct {
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m map[K]*entry[V]
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amended bool // true if the dirty map contains some key not in m.
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}
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// An entry is a slot in the map corresponding to a particular key.
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type entry[V any] struct {
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// p points to the interface{} value stored for the entry.
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//
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// If p == nil, the entry has been deleted, and either m.dirty == nil or
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// m.dirty[key] is e.
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//
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// If p == expunged, the entry has been deleted, m.dirty != nil, and the entry
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// is missing from m.dirty.
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//
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// Otherwise, the entry is valid and recorded in m.read.m[key] and, if m.dirty
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// != nil, in m.dirty[key].
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//
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// An entry can be deleted by atomic replacement with nil: when m.dirty is
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// next created, it will atomically replace nil with expunged and leave
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// m.dirty[key] unset.
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//
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// An entry's associated value can be updated by atomic replacement, provided
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// p != expunged. If p == expunged, an entry's associated value can be updated
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// only after first setting m.dirty[key] = e so that lookups using the dirty
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// map find the entry.
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p unsafe.Pointer // *interface{}
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}
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func newEntry[V any](i V) *entry[V] {
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return &entry[V]{p: unsafe.Pointer(&i)}
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}
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// Load returns the value stored in the map for a key, or nil if no
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// value is present.
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// The ok result indicates whether value was found in the map.
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func (m *Map[K, V]) Load(key K) (value V, ok bool) {
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|
read, _ := m.read.Load().(readOnly[K, V])
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e, ok := read.m[key]
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if !ok && read.amended {
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|
m.mu.Lock()
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// Avoid reporting a spurious miss if m.dirty got promoted while we were
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|
// blocked on m.mu. (If further loads of the same key will not miss, it's
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// not worth copying the dirty map for this key.)
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|
read, _ = m.read.Load().(readOnly[K, V])
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|
e, ok = read.m[key]
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|
if !ok && read.amended {
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|
e, ok = m.dirty[key]
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// Regardless of whether the entry was present, record a miss: this key
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// will take the slow path until the dirty map is promoted to the read
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|
// map.
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|
m.missLocked()
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|
}
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|
m.mu.Unlock()
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|
}
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|
if !ok {
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|
var r V
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|
return r, false
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|
}
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|
return e.load(m.expunged)
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|
}
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|
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|
func (e *entry[V]) load(px unsafe.Pointer) (value V, ok bool) {
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|
p := atomic.LoadPointer(&e.p)
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|
if p == nil || p == px {
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|
var r V
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|
return r, false
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|
}
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|
return *(*V)(p), true
|
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|
}
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|
|
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|
// Store sets the value for a key.
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|
func (m *Map[K, V]) Store(key K, value V) {
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|
read, _ := m.read.Load().(readOnly[K, V])
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|
if e, ok := read.m[key]; ok && e.tryStore(&value, m.expunged) {
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|
return
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|
}
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|
|
||||||
|
m.mu.Lock()
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|
read, _ = m.read.Load().(readOnly[K, V])
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|
if e, ok := read.m[key]; ok {
|
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|
if e.unexpungeLocked(m.expunged) {
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|
// The entry was previously expunged, which implies that there is a
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|
// non-nil dirty map and this entry is not in it.
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|
m.dirty[key] = e
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|
}
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|
e.storeLocked(&value)
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|
} else if e, ok := m.dirty[key]; ok {
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|
e.storeLocked(&value)
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|
} else {
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|
if !read.amended {
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|
// We're adding the first new key to the dirty map.
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|
// Make sure it is allocated and mark the read-only map as incomplete.
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|
m.dirtyLocked()
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|
m.read.Store(readOnly[K, V]{m: read.m, amended: true})
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|
}
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|
m.dirty[key] = newEntry(value)
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|
}
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|
m.mu.Unlock()
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|
}
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|
|
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|
// tryStore stores a value if the entry has not been expunged.
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|
//
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|
// If the entry is expunged, tryStore returns false and leaves the entry
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|
// unchanged.
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|
func (e *entry[V]) tryStore(i *V, px unsafe.Pointer) bool {
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|
for {
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|
p := atomic.LoadPointer(&e.p)
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|
if p == px {
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|
return false
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||||||
|
}
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|
if atomic.CompareAndSwapPointer(&e.p, p, unsafe.Pointer(i)) {
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|
return true
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|
}
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|
}
|
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|
}
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|
||||||
|
// unexpungeLocked ensures that the entry is not marked as expunged.
|
||||||
|
//
|
||||||
|
// If the entry was previously expunged, it must be added to the dirty map
|
||||||
|
// before m.mu is unlocked.
|
||||||
|
func (e *entry[V]) unexpungeLocked(px unsafe.Pointer) (wasExpunged bool) {
|
||||||
|
return atomic.CompareAndSwapPointer(&e.p, px, nil)
|
||||||
|
}
|
||||||
|
|
||||||
|
// storeLocked unconditionally stores a value to the entry.
|
||||||
|
//
|
||||||
|
// The entry must be known not to be expunged.
|
||||||
|
func (e *entry[V]) storeLocked(i *V) {
|
||||||
|
atomic.StorePointer(&e.p, unsafe.Pointer(i))
|
||||||
|
}
|
||||||
|
|
||||||
|
// LoadOrStore returns the existing value for the key if present.
|
||||||
|
// Otherwise, it stores and returns the given value.
|
||||||
|
// The loaded result is true if the value was loaded, false if stored.
|
||||||
|
func (m *Map[K, V]) LoadOrStore(key K, value V) (actual V, loaded bool) {
|
||||||
|
// Avoid locking if it's a clean hit.
|
||||||
|
read, _ := m.read.Load().(readOnly[K, V])
|
||||||
|
if e, ok := read.m[key]; ok {
|
||||||
|
actual, loaded, ok := e.tryLoadOrStore(value, m.expunged)
|
||||||
|
if ok {
|
||||||
|
return actual, loaded
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
m.mu.Lock()
|
||||||
|
read, _ = m.read.Load().(readOnly[K, V])
|
||||||
|
if e, ok := read.m[key]; ok {
|
||||||
|
if e.unexpungeLocked(m.expunged) {
|
||||||
|
m.dirty[key] = e
|
||||||
|
}
|
||||||
|
actual, loaded, _ = e.tryLoadOrStore(value, m.expunged)
|
||||||
|
} else if e, ok := m.dirty[key]; ok {
|
||||||
|
actual, loaded, _ = e.tryLoadOrStore(value, m.expunged)
|
||||||
|
m.missLocked()
|
||||||
|
} else {
|
||||||
|
if !read.amended {
|
||||||
|
// We're adding the first new key to the dirty map.
|
||||||
|
// Make sure it is allocated and mark the read-only map as incomplete.
|
||||||
|
m.dirtyLocked()
|
||||||
|
m.read.Store(readOnly[K, V]{m: read.m, amended: true})
|
||||||
|
}
|
||||||
|
m.dirty[key] = newEntry[V](value)
|
||||||
|
actual, loaded = value, false
|
||||||
|
}
|
||||||
|
m.mu.Unlock()
|
||||||
|
|
||||||
|
return actual, loaded
|
||||||
|
}
|
||||||
|
|
||||||
|
// tryLoadOrStore atomically loads or stores a value if the entry is not
|
||||||
|
// expunged.
|
||||||
|
//
|
||||||
|
// If the entry is expunged, tryLoadOrStore leaves the entry unchanged and
|
||||||
|
// returns with ok==false.
|
||||||
|
func (e *entry[V]) tryLoadOrStore(i V, px unsafe.Pointer) (actual V, loaded, ok bool) {
|
||||||
|
p := atomic.LoadPointer(&e.p)
|
||||||
|
if p == px {
|
||||||
|
var r V
|
||||||
|
return r, false, false
|
||||||
|
}
|
||||||
|
if p != nil {
|
||||||
|
return *(*V)(p), true, true
|
||||||
|
}
|
||||||
|
|
||||||
|
// Copy the interface after the first load to make this method more amenable
|
||||||
|
// to escape analysis: if we hit the "load" path or the entry is expunged, we
|
||||||
|
// shouldn't bother heap-allocating.
|
||||||
|
ic := i
|
||||||
|
for {
|
||||||
|
if atomic.CompareAndSwapPointer(&e.p, nil, unsafe.Pointer(&ic)) {
|
||||||
|
return i, false, true
|
||||||
|
}
|
||||||
|
p = atomic.LoadPointer(&e.p)
|
||||||
|
if p == px {
|
||||||
|
var r V
|
||||||
|
return r, false, false
|
||||||
|
}
|
||||||
|
if p != nil {
|
||||||
|
return *(*V)(p), true, true
|
||||||
|
}
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
// LoadAndDelete deletes the value for a key, returning the previous value if any.
|
||||||
|
// The loaded result reports whether the key was present.
|
||||||
|
func (m *Map[K, V]) LoadAndDelete(key K) (value V, loaded bool) {
|
||||||
|
read, _ := m.read.Load().(readOnly[K, V])
|
||||||
|
e, ok := read.m[key]
|
||||||
|
if !ok && read.amended {
|
||||||
|
m.mu.Lock()
|
||||||
|
read, _ = m.read.Load().(readOnly[K, V])
|
||||||
|
e, ok = read.m[key]
|
||||||
|
if !ok && read.amended {
|
||||||
|
e, ok = m.dirty[key]
|
||||||
|
delete(m.dirty, key)
|
||||||
|
// Regardless of whether the entry was present, record a miss: this key
|
||||||
|
// will take the slow path until the dirty map is promoted to the read
|
||||||
|
// map.
|
||||||
|
m.missLocked()
|
||||||
|
}
|
||||||
|
m.mu.Unlock()
|
||||||
|
}
|
||||||
|
if ok {
|
||||||
|
return e.delete(m.expunged)
|
||||||
|
}
|
||||||
|
var r V
|
||||||
|
return r, false
|
||||||
|
}
|
||||||
|
|
||||||
|
// Delete deletes the value for a key.
|
||||||
|
func (m *Map[K, V]) Delete(key K) {
|
||||||
|
m.LoadAndDelete(key)
|
||||||
|
}
|
||||||
|
|
||||||
|
func (e *entry[V]) delete(px unsafe.Pointer) (value V, ok bool) {
|
||||||
|
for {
|
||||||
|
p := atomic.LoadPointer(&e.p)
|
||||||
|
if p == nil || p == px {
|
||||||
|
var r V
|
||||||
|
return r, false
|
||||||
|
}
|
||||||
|
if atomic.CompareAndSwapPointer(&e.p, p, nil) {
|
||||||
|
return *(*V)(p), true
|
||||||
|
}
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
// Range calls f sequentially for each key and value present in the map.
|
||||||
|
// If f returns false, range stops the iteration.
|
||||||
|
//
|
||||||
|
// Range does not necessarily correspond to any consistent snapshot of the Map's
|
||||||
|
// contents: no key will be visited more than once, but if the value for any key
|
||||||
|
// is stored or deleted concurrently (including by f), Range may reflect any
|
||||||
|
// mapping for that key from any point during the Range call. Range does not
|
||||||
|
// block other methods on the receiver; even f itself may call any method on m.
|
||||||
|
//
|
||||||
|
// Range may be O(N) with the number of elements in the map even if f returns
|
||||||
|
// false after a constant number of calls.
|
||||||
|
func (m *Map[K, V]) Range(f func(key K, value V) bool) {
|
||||||
|
// We need to be able to iterate over all the keys that were already
|
||||||
|
// present at the start of the call to Range.
|
||||||
|
// If read.amended is false, then read.m satisfies that property without
|
||||||
|
// requiring us to hold m.mu for a long time.
|
||||||
|
read, _ := m.read.Load().(readOnly[K, V])
|
||||||
|
if read.amended {
|
||||||
|
// m.dirty contains keys not in read.m. Fortunately, Range is already O(N)
|
||||||
|
// (assuming the caller does not break out early), so a call to Range
|
||||||
|
// amortizes an entire copy of the map: we can promote the dirty copy
|
||||||
|
// immediately!
|
||||||
|
m.mu.Lock()
|
||||||
|
read, _ = m.read.Load().(readOnly[K, V])
|
||||||
|
if read.amended {
|
||||||
|
read = readOnly[K, V]{m: m.dirty}
|
||||||
|
m.read.Store(read)
|
||||||
|
m.dirty = nil
|
||||||
|
m.misses = 0
|
||||||
|
}
|
||||||
|
m.mu.Unlock()
|
||||||
|
}
|
||||||
|
|
||||||
|
for k, e := range read.m {
|
||||||
|
v, ok := e.load(m.expunged)
|
||||||
|
if !ok {
|
||||||
|
continue
|
||||||
|
}
|
||||||
|
if !f(k, v) {
|
||||||
|
break
|
||||||
|
}
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
func (m *Map[K, V]) missLocked() {
|
||||||
|
m.misses++
|
||||||
|
if m.misses < len(m.dirty) {
|
||||||
|
return
|
||||||
|
}
|
||||||
|
m.read.Store(readOnly[K, V]{m: m.dirty})
|
||||||
|
m.dirty = nil
|
||||||
|
m.misses = 0
|
||||||
|
}
|
||||||
|
|
||||||
|
func (m *Map[K, V]) dirtyLocked() {
|
||||||
|
if m.dirty != nil {
|
||||||
|
return
|
||||||
|
}
|
||||||
|
|
||||||
|
read, _ := m.read.Load().(readOnly[K, V])
|
||||||
|
m.dirty = make(map[K]*entry[V], len(read.m))
|
||||||
|
for k, e := range read.m {
|
||||||
|
if !e.tryExpungeLocked(m.expunged) {
|
||||||
|
m.dirty[k] = e
|
||||||
|
}
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
func (e *entry[V]) tryExpungeLocked(px unsafe.Pointer) (isExpunged bool) {
|
||||||
|
p := atomic.LoadPointer(&e.p)
|
||||||
|
for p == nil {
|
||||||
|
if atomic.CompareAndSwapPointer(&e.p, nil, px) {
|
||||||
|
return true
|
||||||
|
}
|
||||||
|
p = atomic.LoadPointer(&e.p)
|
||||||
|
}
|
||||||
|
return p == px
|
||||||
|
}
|
Loading…
Reference in New Issue
Block a user