From f71245504726a717c8a85ecd99f83a7395bd3c2b Mon Sep 17 00:00:00 2001
From: Jonas Platte <jplatte+git@posteo.de>
Date: Sat, 27 Nov 2021 16:35:59 +0100
Subject: [PATCH] Reduce EventId copying

---
 src/client_server/membership.rs |  3 ++-
 src/database/rooms.rs           | 14 ++++++++++----
 src/server_server.rs            | 22 ++++++++--------------
 3 files changed, 20 insertions(+), 19 deletions(-)

diff --git a/src/client_server/membership.rs b/src/client_server/membership.rs
index 6c7b7211..e6c9d4b6 100644
--- a/src/client_server/membership.rs
+++ b/src/client_server/membership.rs
@@ -31,6 +31,7 @@ use serde_json::value::{to_raw_value, RawValue as RawJsonValue};
 use std::{
     collections::{hash_map::Entry, BTreeMap, HashMap, HashSet},
     convert::{TryFrom, TryInto},
+    iter,
     sync::{Arc, RwLock},
     time::{Duration, Instant},
 };
@@ -740,7 +741,7 @@ async fn join_room_by_id_helper(
         db.rooms.append_pdu(
             &pdu,
             utils::to_canonical_object(&pdu).expect("Pdu is valid canonical object"),
-            &[pdu.event_id.clone()],
+            iter::once(&*pdu.event_id),
             db,
         )?;
 
diff --git a/src/database/rooms.rs b/src/database/rooms.rs
index f8d2cad8..4c092bf7 100644
--- a/src/database/rooms.rs
+++ b/src/database/rooms.rs
@@ -36,6 +36,8 @@ use std::{
     borrow::Cow,
     collections::{BTreeMap, HashMap, HashSet},
     convert::{TryFrom, TryInto},
+    fmt::Debug,
+    iter,
     mem::size_of,
     sync::{Arc, Mutex, RwLock},
     time::Instant,
@@ -1191,7 +1193,11 @@ impl Rooms {
     /// The provided `event_ids` become the new leaves, this allows a room to have multiple
     /// `prev_events`.
     #[tracing::instrument(skip(self))]
-    pub fn replace_pdu_leaves(&self, room_id: &RoomId, event_ids: &[Box<EventId>]) -> Result<()> {
+    pub fn replace_pdu_leaves<'a>(
+        &self,
+        room_id: &RoomId,
+        event_ids: impl IntoIterator<Item = &'a EventId> + Debug,
+    ) -> Result<()> {
         let mut prefix = room_id.as_bytes().to_vec();
         prefix.push(0xff);
 
@@ -1255,11 +1261,11 @@ impl Rooms {
     ///
     /// Returns pdu id
     #[tracing::instrument(skip(self, pdu, pdu_json, leaves, db))]
-    pub fn append_pdu(
+    pub fn append_pdu<'a>(
         &self,
         pdu: &PduEvent,
         mut pdu_json: CanonicalJsonObject,
-        leaves: &[Box<EventId>],
+        leaves: impl IntoIterator<Item = &'a EventId> + Debug,
         db: &Database,
     ) -> Result<Vec<u8>> {
         let shortroomid = self.get_shortroomid(&pdu.room_id)?.expect("room exists");
@@ -2104,7 +2110,7 @@ impl Rooms {
             pdu_json,
             // Since this PDU references all pdu_leaves we can update the leaves
             // of the room
-            &[pdu.event_id.clone()],
+            iter::once(&*pdu.event_id),
             db,
         )?;
 
diff --git a/src/server_server.rs b/src/server_server.rs
index b0e3f0f6..ca6bb3fd 100644
--- a/src/server_server.rs
+++ b/src/server_server.rs
@@ -64,6 +64,7 @@ use std::{
     future::Future,
     mem,
     net::{IpAddr, SocketAddr},
+    ops::Deref,
     pin::Pin,
     sync::{Arc, RwLock, RwLockWriteGuard},
     time::{Duration, Instant, SystemTime},
@@ -1636,7 +1637,7 @@ async fn upgrade_outlier_to_timeline_pdu(
             db,
             &incoming_pdu,
             val,
-            extremities,
+            extremities.iter().map(Deref::deref),
             state_ids_compressed,
             soft_fail,
             &state_lock,
@@ -1821,7 +1822,7 @@ async fn upgrade_outlier_to_timeline_pdu(
         db,
         &incoming_pdu,
         val,
-        extremities,
+        extremities.iter().map(Deref::deref),
         state_ids_compressed,
         soft_fail,
         &state_lock,
@@ -2114,11 +2115,11 @@ pub(crate) async fn fetch_signing_keys(
 /// Append the incoming event setting the state snapshot to the state from the
 /// server that sent the event.
 #[tracing::instrument(skip(db, pdu, pdu_json, new_room_leaves, state_ids_compressed, _mutex_lock))]
-fn append_incoming_pdu(
+fn append_incoming_pdu<'a>(
     db: &Database,
     pdu: &PduEvent,
     pdu_json: CanonicalJsonObject,
-    new_room_leaves: HashSet<Box<EventId>>,
+    new_room_leaves: impl IntoIterator<Item = &'a EventId> + Clone + Debug,
     state_ids_compressed: HashSet<CompressedStateEvent>,
     soft_fail: bool,
     _mutex_lock: &MutexGuard<'_, ()>, // Take mutex guard to make sure users get the room mutex
@@ -2135,19 +2136,12 @@ fn append_incoming_pdu(
     if soft_fail {
         db.rooms
             .mark_as_referenced(&pdu.room_id, &pdu.prev_events)?;
-        db.rooms.replace_pdu_leaves(
-            &pdu.room_id,
-            &new_room_leaves.into_iter().collect::<Vec<_>>(),
-        )?;
+        db.rooms
+            .replace_pdu_leaves(&pdu.room_id, new_room_leaves.clone())?;
         return Ok(None);
     }
 
-    let pdu_id = db.rooms.append_pdu(
-        pdu,
-        pdu_json,
-        &new_room_leaves.into_iter().collect::<Vec<_>>(),
-        db,
-    )?;
+    let pdu_id = db.rooms.append_pdu(pdu, pdu_json, new_room_leaves, db)?;
 
     for appservice in db.appservice.all()? {
         if db.rooms.appservice_in_room(&pdu.room_id, &appservice, db)? {