WIP: Track grant ownership.

src/common/mod.rs

@@ -1,3 +1,8 @@
+use alloc::boxed::Box;
+use alloc::vec::Vec;
+
+use crate::memory::Enomem;
+
 pub mod aligned_box;
 #[macro_use]
 pub mod int_like;
@@ -26,3 +31,14 @@ macro_rules! dbg {
         ($($crate::dbg!($val)),+,)
     };
 }
+
+pub fn try_new_vec_with_exact_size<T>(len: usize) -> Result<Vec<T>, Enomem> {
+    let mut vec = Vec::new();
+    vec.try_reserve_exact(len).map_err(|_| Enomem)?;
+    Ok(vec.into())
+}
+pub fn try_box_slice_new<T: Clone>(value: T, len: usize) -> Result<Box<[T]>, Enomem> {
+    let mut vec = try_new_vec_with_exact_size(len)?;
+    vec.resize(len, value);
+    Ok(vec.into())
+}