first-commit

modules/globallock/memory_locker.go

@@ -0,0 +1,67 @@
+// Copyright 2024 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package globallock
+
+import (
+	"context"
+	"sync"
+	"time"
+)
+
+type memoryLocker struct {
+	locks sync.Map
+}
+
+var _ Locker = &memoryLocker{}
+
+func NewMemoryLocker() Locker {
+	return &memoryLocker{}
+}
+
+func (l *memoryLocker) Lock(ctx context.Context, key string) (ReleaseFunc, error) {
+	if l.tryLock(key) {
+		releaseOnce := sync.Once{}
+		return func() {
+			releaseOnce.Do(func() {
+				l.locks.Delete(key)
+			})
+		}, nil
+	}
+
+	ticker := time.NewTicker(time.Millisecond * 100)
+	defer ticker.Stop()
+	for {
+		select {
+		case <-ctx.Done():
+			return func() {}, ctx.Err()
+		case <-ticker.C:
+			if l.tryLock(key) {
+				releaseOnce := sync.Once{}
+				return func() {
+					releaseOnce.Do(func() {
+						l.locks.Delete(key)
+					})
+				}, nil
+			}
+		}
+	}
+}
+
+func (l *memoryLocker) TryLock(_ context.Context, key string) (bool, ReleaseFunc, error) {
+	if l.tryLock(key) {
+		releaseOnce := sync.Once{}
+		return true, func() {
+			releaseOnce.Do(func() {
+				l.locks.Delete(key)
+			})
+		}, nil
+	}
+
+	return false, func() {}, nil
+}
+
+func (l *memoryLocker) tryLock(key string) bool {
+	_, loaded := l.locks.LoadOrStore(key, struct{}{})
+	return !loaded
+}