From aef2c5dc142b455274f62367d2874c58cc08bba5 Mon Sep 17 00:00:00 2001
From: Max Kellermann <mk@cm4all.com>
Date: Thu, 18 Jan 2024 16:04:40 +0100
Subject: [PATCH] lib/avahi/Service: add field `visible`

Now individual services can be hidden or shown at any time.
---
 src/lib/avahi/Publisher.cxx | 18 +++++++++++-------
 src/lib/avahi/Publisher.hxx |  6 ++++++
 src/lib/avahi/Service.hxx   |  7 +++++++
 3 files changed, 24 insertions(+), 7 deletions(-)

diff --git a/src/lib/avahi/Publisher.cxx b/src/lib/avahi/Publisher.cxx
index 64cfd43ae..e9dd95202 100644
--- a/src/lib/avahi/Publisher.cxx
+++ b/src/lib/avahi/Publisher.cxx
@@ -55,22 +55,25 @@ Publisher::~Publisher() noexcept
 	client.RemoveListener(*this);
 }
 
+void
+Publisher::UpdateServices() noexcept
+{
+	if (visible && client.IsConnected())
+		defer_register_services.Schedule();
+}
+
 void
 Publisher::AddService(Service &service) noexcept
 {
 	services.push_back(service);
-
-	if (visible && client.IsConnected())
-		defer_register_services.Schedule();
+	UpdateServices();
 }
 
 void
 Publisher::RemoveService(Service &service) noexcept
 {
 	services.erase(services.iterator_to(service));
-
-	if (visible && client.IsConnected())
-		defer_register_services.Schedule();
+	UpdateServices();
 }
 
 inline void
@@ -141,7 +144,8 @@ AddServices(AvahiEntryGroup &group,
 	    const IntrusiveList<Service> &services, const char *name)
 {
 	for (const auto &i : services)
-		AddService(group, i, name);
+		if (i.visible)
+			AddService(group, i, name);
 }
 
 void
diff --git a/src/lib/avahi/Publisher.hxx b/src/lib/avahi/Publisher.hxx
index cabdcbaeb..dcd3f3e8c 100644
--- a/src/lib/avahi/Publisher.hxx
+++ b/src/lib/avahi/Publisher.hxx
@@ -59,6 +59,12 @@ public:
 	Publisher(const Publisher &) = delete;
 	Publisher &operator=(const Publisher &) = delete;
 
+	/**
+	 * Call this after a #Service field was modified to publish
+	 * the changes.
+	 */
+	void UpdateServices() noexcept;
+
 	/**
 	 * Publish another service.
 	 *
diff --git a/src/lib/avahi/Service.hxx b/src/lib/avahi/Service.hxx
index 432d374c1..abc26d05e 100644
--- a/src/lib/avahi/Service.hxx
+++ b/src/lib/avahi/Service.hxx
@@ -22,6 +22,13 @@ struct Service : IntrusiveListHook<> {
 	std::string type;
 	uint16_t port;
 
+	/**
+	 * If this is false, then the service is not published.  You
+	 * can change this field at any time and then call
+	 * Publisher::UpdateServices() to publish the change.
+	 */
+	bool visible = true;
+
 	Service(AvahiIfIndex _interface, AvahiProtocol _protocol,
 		const char *_type, uint16_t _port) noexcept
 		:interface(_interface), protocol(_protocol),