Split protocol internals by responsibility

src/protocol/session/storage.rs

@@ -0,0 +1,70 @@
+use alloc::vec::Vec;
+
+use crate::protocol::{HookID, PacketQueue};
+
+/// Storage entry used by macro-generated session stores.
+///
+/// The fields are public so generated code in downstream crates can keep the update
+/// loop straightforward and static. Handwritten leaves may also use this type, but it
+/// is intentionally small rather than a full session framework.
+pub struct SessionEntry<S> {
+    /// Hook id associated with this live session.
+    pub hook_id: HookID,
+
+    /// Application-owned session state.
+    pub state: S,
+
+    /// Packets delivered for this hook but not yet consumed by the session.
+    pub inbox: PacketQueue,
+
+    /// Whether application logic has finished and should be removed after update.
+    pub closed: bool,
+}
+
+/// Generated storage for one session family.
+///
+/// The macro only names this field and picks the concrete `Session` type. All update,
+/// retry, and cleanup behavior lives in normal Rust helpers so the template stays
+/// small and readable.
+pub struct SessionFamily<S> {
+    /// Active hook-backed sessions for this family.
+    pub entries: Vec<SessionEntry<S>>,
+}
+
+impl<S> SessionFamily<S> {
+    /// Creates an empty session family.
+    pub fn new() -> Self {
+        Self {
+            entries: Vec::new(),
+        }
+    }
+
+    /// Counts packets retained by this family for retry or future session work.
+    pub fn pending_packet_count(&self) -> usize {
+        let mut count = 0usize;
+
+        for entry in &self.entries {
+            count += entry.inbox.len();
+        }
+
+        count
+    }
+}
+
+impl<S> Default for SessionFamily<S> {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
+impl<S> SessionEntry<S> {
+    /// Creates one active session entry for `hook_id`.
+    pub fn new(hook_id: HookID, state: S) -> Self {
+        Self {
+            hook_id,
+            state,
+            inbox: PacketQueue::new(),
+            closed: false,
+        }
+    }
+}