Implement domain and endpoint modules with capability management, message passing, and scheduling features

crates/domain/src/capability/mod.rs

@@ -0,0 +1,82 @@
+use types::{bounded::CapSlot, generation::Generation, permission::PermissionSet};
+
+pub mod authority;
+
+use crate::{error::KernelError, resource::Resource};
+
+#[cfg(test)]
+#[path = "tests.rs"]
+mod tests;
+
+const MAX_CAPS_PER_PROCESS: usize = 16;
+
+pub struct Capability {
+    resource: Resource,
+    permissions: PermissionSet,
+    generation: Generation,
+}
+
+impl Capability {
+    pub(crate) fn new(
+        resource: Resource,
+        permissions: PermissionSet,
+        generation: Generation,
+    ) -> Self {
+        Self {
+            resource,
+            permissions,
+            generation,
+        }
+    }
+
+    pub fn resource(&self) -> &Resource {
+        &self.resource
+    }
+
+    pub fn permissions(&self) -> &PermissionSet {
+        &self.permissions
+    }
+
+    pub fn generation(&self) -> &Generation {
+        &self.generation
+    }
+}
+
+pub struct CapabilityTable {
+    slots: [Option<Capability>; MAX_CAPS_PER_PROCESS],
+}
+
+impl CapabilityTable {
+    pub fn new() -> Self {
+        Self {
+            slots: [const { None }; MAX_CAPS_PER_PROCESS],
+        }
+    }
+
+    pub fn get(&self, slot: CapSlot) -> Result<&Capability, KernelError> {
+        let idx = slot.value() as usize;
+        self.slots[idx]
+            .as_ref()
+            .ok_or(KernelError::InvalidSlot(slot))
+    }
+
+    pub fn insert(&mut self, cap: Capability) -> Result<CapSlot, KernelError> {
+        let idx = self
+            .slots
+            .iter()
+            .position(|s| s.is_none())
+            .ok_or(KernelError::NoFreeSlot)?;
+
+        self.slots[idx] = Some(cap);
+        CapSlot::new(idx as u8).ok_or(KernelError::NoFreeSlot)
+    }
+
+    pub fn remove(&mut self, slot: CapSlot) -> Result<(), KernelError> {
+        let idx = slot.value() as usize;
+        if self.slots[idx].is_none() {
+            return Err(KernelError::InvalidSlot(slot));
+        }
+        self.slots[idx] = None;
+        Ok(())
+    }
+}