1 files changed, 48 insertions, 0 deletions
diff --git a/rust/kernel/alloc/vec_ext.rs b/rust/kernel/alloc/vec_ext.rs
new file mode 100644
index 000000000000..311e62cc5784
--- /dev/null
+++ b/rust/kernel/alloc/vec_ext.rs
@@ -0,0 +1,48 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! Extensions to [`Vec`] for fallible allocations.
+
+use alloc::{collections::TryReserveError, vec::Vec};
+use core::result::Result;
+
+/// Extensions to [`Vec`].
+pub trait VecExt<T>: Sized {
+    /// Creates a new [`Vec`] instance with at least the given capacity.
+    fn try_with_capacity(capacity: usize) -> Result<Self, TryReserveError>;
+
+    /// Appends an element to the back of the [`Vec`] instance.
+    fn try_push(&mut self, v: T) -> Result<(), TryReserveError>;
+
+    /// Pushes clones of the elements of slice into the [`Vec`] instance.
+    fn try_extend_from_slice(&mut self, other: &[T]) -> Result<(), TryReserveError>
+    where
+        T: Clone;
+}
+
+impl<T> VecExt<T> for Vec<T> {
+    fn try_with_capacity(capacity: usize) -> Result<Self, TryReserveError> {
+        let mut v = Vec::new();
+        v.try_reserve(capacity)?;
+        Ok(v)
+    }
+
+    fn try_push(&mut self, v: T) -> Result<(), TryReserveError> {
+        if let Err(retry) = self.push_within_capacity(v) {
+            self.try_reserve(1)?;
+            let _ = self.push_within_capacity(retry);
+        }
+        Ok(())
+    }
+
+    fn try_extend_from_slice(&mut self, other: &[T]) -> Result<(), TryReserveError>
+    where
+        T: Clone,
+    {
+        self.try_reserve(other.len())?;
+        for item in other {
+            self.try_push(item.clone())?;
+        }
+
+        Ok(())
+    }
+}