add IdAllocator

Signed-off-by: Richard Chien <[email protected]>

Author: stdrc

src/common/src/util/id_alloc.rs

@@ -0,0 +1,60 @@
+// Copyright 2024 RisingWave Labs
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+use std::ops::Add;
+
+use num_traits::{CheckedAdd, One};
+
+#[derive(Debug, Clone, Copy)]
+pub struct IdAllocator<T> {
+    next: T,
+}
+
+impl<T> IdAllocator<T>
+where
+    T: One,
+{
+    pub fn new() -> Self {
+        Self { next: T::one() }
+    }
+}
+
+impl<T> Default for IdAllocator<T>
+where
+    T: One,
+{
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
+impl<T> IdAllocator<T>
+where
+    T: Copy + Add<Output = T> + One,
+{
+    pub fn next(&mut self) -> T {
+        let next_next = self.next + T::one();
+        std::mem::replace(&mut self.next, next_next)
+    }
+}
+
+impl<T> IdAllocator<T>
+where
+    T: CheckedAdd + One,
+{
+    pub fn checked_next(&mut self) -> Option<T> {
+        let next_next = self.next.checked_add(&T::one())?;
+        Some(std::mem::replace(&mut self.next, next_next))
+    }
+}

src/common/src/util/mod.rs

@@ -43,3 +43,4 @@ pub mod value_encoding;
 pub mod worker_util;
 pub use tokio_util;
 pub mod cluster_limit;
+pub mod id_alloc;