From 1c3a1c842d8e59683a7afb7a5ad15b3a6f4d647b Mon Sep 17 00:00:00 2001
From: Max Kellermann <max.kellermann@gmail.com>
Date: Mon, 6 May 2024 17:15:24 +0200
Subject: [PATCH] lib/nfs/Lease: use InstrusiveList instead of std::list

---
 src/lib/nfs/Connection.cxx | 35 +++++++++++++++++++----------------
 src/lib/nfs/Connection.hxx | 11 +++--------
 src/lib/nfs/Lease.hxx      |  9 ++++-----
 3 files changed, 26 insertions(+), 29 deletions(-)

diff --git a/src/lib/nfs/Connection.cxx b/src/lib/nfs/Connection.cxx
index d6910a7a5..39d0969a6 100644
--- a/src/lib/nfs/Connection.cxx
+++ b/src/lib/nfs/Connection.cxx
@@ -173,6 +173,15 @@ events_to_libnfs(unsigned i) noexcept
 		((i & SocketEvent::ERROR) ? POLLERR : 0);
 }
 
+NfsConnection::NfsConnection(EventLoop &_loop,
+			     std::string_view _server,
+			     std::string_view _export_name) noexcept
+	:socket_event(_loop, BIND_THIS_METHOD(OnSocketReady)),
+	 defer_new_lease(_loop, BIND_THIS_METHOD(RunDeferred)),
+	 mount_timeout_event(_loop, BIND_THIS_METHOD(OnMountTimeout)),
+	 server(_server), export_name(_export_name),
+	 context(nullptr) {}
+
 NfsConnection::~NfsConnection() noexcept
 {
 	assert(GetEventLoop().IsInside());
@@ -190,7 +199,7 @@ NfsConnection::AddLease(NfsLease &lease) noexcept
 {
 	assert(GetEventLoop().IsInside());
 
-	new_leases.push_back(&lease);
+	new_leases.push_back(lease);
 
 	defer_new_lease.Schedule();
 }
@@ -200,8 +209,7 @@ NfsConnection::RemoveLease(NfsLease &lease) noexcept
 {
 	assert(GetEventLoop().IsInside());
 
-	new_leases.remove(&lease);
-	active_leases.remove(&lease);
+	lease.unlink();
 }
 
 void
@@ -581,11 +589,10 @@ NfsConnection::BroadcastMountSuccess() noexcept
 {
 	assert(GetEventLoop().IsInside());
 
-	while (!new_leases.empty()) {
-		auto i = new_leases.begin();
-		active_leases.splice(active_leases.end(), new_leases, i);
-		(*i)->OnNfsConnectionReady();
-	}
+	new_leases.clear_and_dispose([this](auto *lease){
+		active_leases.push_back(*lease);
+		lease->OnNfsConnectionReady();
+	});
 }
 
 void
@@ -593,11 +600,9 @@ NfsConnection::BroadcastMountError(std::exception_ptr e) noexcept
 {
 	assert(GetEventLoop().IsInside());
 
-	while (!new_leases.empty()) {
-		auto l = new_leases.front();
-		new_leases.pop_front();
+	new_leases.clear_and_dispose([this, &e](auto *l){
 		l->OnNfsConnectionFailed(e);
-	}
+	});
 
 	OnNfsConnectionError(std::move(e));
 }
@@ -607,11 +612,9 @@ NfsConnection::BroadcastError(std::exception_ptr e) noexcept
 {
 	assert(GetEventLoop().IsInside());
 
-	while (!active_leases.empty()) {
-		auto l = active_leases.front();
-		active_leases.pop_front();
+	active_leases.clear_and_dispose([this, &e](auto *l){
 		l->OnNfsConnectionDisconnected(e);
-	}
+	});
 
 	BroadcastMountError(std::move(e));
 }
diff --git a/src/lib/nfs/Connection.hxx b/src/lib/nfs/Connection.hxx
index 1debc0a05..8b1667906 100644
--- a/src/lib/nfs/Connection.hxx
+++ b/src/lib/nfs/Connection.hxx
@@ -7,9 +7,9 @@
 #include "event/SocketEvent.hxx"
 #include "event/CoarseTimerEvent.hxx"
 #include "event/DeferEvent.hxx"
+#include "util/IntrusiveList.hxx"
 
 #include <string>
-#include <list>
 #include <forward_list>
 #include <exception>
 
@@ -83,7 +83,7 @@ class NfsConnection {
 
 	nfs_context *context;
 
-	typedef std::list<NfsLease *> LeaseList;
+	using LeaseList = IntrusiveList<NfsLease>;
 	LeaseList new_leases, active_leases;
 
 	typedef CancellableList<NfsCallback, CancellableCallback> CallbackList;
@@ -124,12 +124,7 @@ public:
 	[[gnu::nonnull]]
 	NfsConnection(EventLoop &_loop,
 		      std::string_view _server,
-		      std::string_view _export_name) noexcept
-		:socket_event(_loop, BIND_THIS_METHOD(OnSocketReady)),
-		 defer_new_lease(_loop, BIND_THIS_METHOD(RunDeferred)),
-		 mount_timeout_event(_loop, BIND_THIS_METHOD(OnMountTimeout)),
-		 server(_server), export_name(_export_name),
-		 context(nullptr) {}
+		      std::string_view _export_name) noexcept;
 
 	/**
 	 * Must be run from EventLoop's thread.
diff --git a/src/lib/nfs/Lease.hxx b/src/lib/nfs/Lease.hxx
index 4e2574971..f3025d4b3 100644
--- a/src/lib/nfs/Lease.hxx
+++ b/src/lib/nfs/Lease.hxx
@@ -1,12 +1,13 @@
 // SPDX-License-Identifier: GPL-2.0-or-later
 // Copyright The Music Player Daemon Project
 
-#ifndef MPD_NFS_LEASE_HXX
-#define MPD_NFS_LEASE_HXX
+#pragma once
+
+#include "util/IntrusiveList.hxx"
 
 #include <exception>
 
-class NfsLease {
+class NfsLease : public IntrusiveListHook<> {
 public:
 	/**
 	 * The #NfsConnection has successfully mounted the server's
@@ -26,5 +27,3 @@ public:
 	 */
 	virtual void OnNfsConnectionDisconnected(std::exception_ptr e) noexcept = 0;
 };
-
-#endif