# HG changeset patch
# User Paul Boddie <paul@boddie.org.uk>
# Date 1679502665 -3600
# Node ID b33673595ce04cd41d61cebd815eee2bf2b42a2e
# Parent  07dd3f43693ea16e974ca8b7e1a6ac485d2db4a4
Separated auto-deletion from general notifications related to IPC.

diff -r 07dd3f43693e -r b33673595ce0 libipc/include/ipc/server.h
--- a/libipc/include/ipc/server.h	Wed Mar 22 16:15:04 2023 +0100
+++ b/libipc/include/ipc/server.h	Wed Mar 22 17:31:05 2023 +0100
@@ -86,6 +86,7 @@
 
   int notifications;
   l4_cap_idx_t irq;
+  int auto_deletion;
 
 } ipc_server_config_type;
 
@@ -100,13 +101,17 @@
 
 
 
-/* Associate a notification IRQ with an IPC gate in the main thread. */
+/* Associate a notification IRQ with the main thread. */
 
-long ipc_server_apply_irq(l4_cap_idx_t cap, l4_cap_idx_t *irq);
+long ipc_server_apply_irq(l4_cap_idx_t *irq);
+
+/* Associate a notification IRQ with the given thread. */
 
-/* Associate a notification IRQ with an IPC gate in the given thread. */
+long ipc_server_apply_irq_for_thread(l4_cap_idx_t *irq, l4_cap_idx_t thread);
 
-long ipc_server_apply_irq_for_thread(l4_cap_idx_t cap, l4_cap_idx_t *irq, l4_cap_idx_t thread);
+/* Apply auto-deletion to an IRQ associated with the given thread. */
+
+long ipc_server_apply_deletion_for_thread(l4_cap_idx_t cap, l4_cap_idx_t irq, l4_cap_idx_t thread);
 
 /* Bind the main thread to a named IPC gate capability. */
 
diff -r 07dd3f43693e -r b33673595ce0 libipc/lib/src/server.c
--- a/libipc/lib/src/server.c	Wed Mar 22 16:15:04 2023 +0100
+++ b/libipc/lib/src/server.c	Wed Mar 22 17:31:05 2023 +0100
@@ -34,18 +34,16 @@
 
 
 
-/* Associate an IRQ with the IPC gate in the main thread to handle gate deletion
-   notifications. */
+/* Associate an IRQ with the main thread. */
 
-long ipc_server_apply_irq(l4_cap_idx_t cap, l4_cap_idx_t *irq)
+long ipc_server_apply_irq(l4_cap_idx_t *irq)
 {
-  return ipc_server_apply_irq_for_thread(cap, irq, l4re_env()->main_thread);
+  return ipc_server_apply_irq_for_thread(irq, l4re_env()->main_thread);
 }
 
-/* Associate an IRQ with the IPC gate in the given thread to handle gate deletion
-   notifications. */
+/* Associate an IRQ with the given thread. */
 
-long ipc_server_apply_irq_for_thread(l4_cap_idx_t cap, l4_cap_idx_t *irq, l4_cap_idx_t thread)
+long ipc_server_apply_irq_for_thread(l4_cap_idx_t *irq, l4_cap_idx_t thread)
 {
   /* Create an IRQ for the gate. */
 
@@ -65,14 +63,23 @@
     return err;
   }
 
+  return L4_EOK;
+}
+
+/* Associate the given IRQ with gate deletion notifications, also decreasing the
+   IPC gate reference count so that such a notification will be delivered when
+   the final client of the IPC gate releases its reference to it. */
+
+long ipc_server_apply_deletion_for_thread(l4_cap_idx_t cap, l4_cap_idx_t irq, l4_cap_idx_t thread)
+{
   /* Register for notifications. The thread associated with the gate seems to be
      needed. */
 
-  err = l4_error(l4_thread_register_del_irq(thread, *irq));
+  long err = l4_error(l4_thread_register_del_irq(thread, irq));
 
   if (err)
   {
-    ipc_cap_free_um(*irq);
+    ipc_cap_free_um(irq);
     return err;
   }
 
@@ -249,7 +256,7 @@
 
     irq_label = (l4_umword_t) config->irq;
 
-    if (!config->notifications || (config->notifications && (label != irq_label)))
+    if (label != irq_label)
     {
       config_from_label = (ipc_server_config_type *) label;
       config_from_label->handler(&msg, config_from_label->handler_obj);
@@ -257,7 +264,7 @@
 
     /* Message involves the IRQ or a termination condition occurred. */
 
-    else if ((config->notifications && (label == irq_label)) || msg.terminating)
+    else if ((label == irq_label) || msg.terminating)
       break;
   }
 
@@ -355,10 +362,12 @@
   config->thread = l4re_env()->main_thread;
   config->server = L4_INVALID_CAP;
 
-  /* No notifications and with IRQ to be potentially allocated. */
+  /* No notifications and with IRQ to be potentially allocated. Auto-deletion is
+     also disabled by default. */
 
   config->notifications = 0;
   config->irq = L4_INVALID_CAP;
+  config->auto_deletion = 0;
 }
 
 /* Initialise but do not start a server using the given configuration. */
@@ -381,11 +390,21 @@
 
   if (config->notifications)
   {
-    err = ipc_server_apply_irq_for_thread(config->server, &config->irq, config->thread);
+    err = ipc_server_apply_irq_for_thread(&config->irq, config->thread);
 
     if (err)
       return err;
 
+    /* Apply auto-deletion if appropriate. */
+
+    if (config->auto_deletion)
+    {
+      err = ipc_server_apply_deletion_for_thread(config->server, config->irq, config->thread);
+
+      if (err)
+        return err;
+    }
+
     /* Unmask the interrupt. */
 
     ipc_init_irq(config->irq);
diff -r 07dd3f43693e -r b33673595ce0 libnotifier/lib/src/notifier.cc
--- a/libnotifier/lib/src/notifier.cc	Wed Mar 22 16:15:04 2023 +0100
+++ b/libnotifier/lib/src/notifier.cc	Wed Mar 22 17:31:05 2023 +0100
@@ -103,7 +103,7 @@
 
   NotifierResource *notifier = new NotifierResource;
   ResourceServer server(notifier);
-  long err = server.start_thread(false);
+  long err = server.start_thread(true, false);
 
   if (err)
     return err;
@@ -152,7 +152,7 @@
 
     NotifierResource *resource = new NotifierResource(this, object);
     ResourceServer server(resource);
-    long err = server.start_in_thread(_configs.front()->thread, false);
+    long err = server.start_in_thread(_configs.front()->thread);
 
     if (err)
       return err;
diff -r 07dd3f43693e -r b33673595ce0 libresource/include/resource/resource_server.h
--- a/libresource/include/resource/resource_server.h	Wed Mar 22 16:15:04 2023 +0100
+++ b/libresource/include/resource/resource_server.h	Wed Mar 22 17:31:05 2023 +0100
@@ -55,11 +55,12 @@
 
   long start(bool finalisation = false);
 
-  long start_in_thread(l4_cap_idx_t thread, bool finalisation = false);
+  long start_in_thread(l4_cap_idx_t thread);
 
-  long start_thread(bool finalisation = true);
+  long start_thread(bool finalisation = true, bool auto_deletion = true);
 
-  long start_thread(l4_cap_idx_t *server, bool finalisation = true);
+  long start_thread(l4_cap_idx_t *server, bool finalisation = true,
+                    bool auto_deletion = true);
 };
 
 
@@ -69,8 +70,8 @@
 void resource_init_config(ipc_server_config_type *config, Resource *resource);
 
 void resource_set_config_threaded(ipc_server_config_type *config,
-                                  l4_cap_idx_t thread, int new_thread,
-                                  int finalisation);
+                                  l4_cap_idx_t thread, int separate_thread,
+                                  int finalisation, int auto_deletion);
 
 /* Server initiation. */
 
diff -r 07dd3f43693e -r b33673595ce0 libresource/lib/src/resource_server.cc
--- a/libresource/lib/src/resource_server.cc	Wed Mar 22 16:15:04 2023 +0100
+++ b/libresource/lib/src/resource_server.cc	Wed Mar 22 17:31:05 2023 +0100
@@ -38,8 +38,8 @@
   return ipc_server_bind(name, (l4_umword_t) _config, &_config->server);
 }
 
-/* Start in the same thread indicating whether deletion notifications and
-   finalisation are to be used. */
+/* Start in the same thread indicating whether the server can be finalised. If
+   so, deletion notifications will be used. */
 
 long ResourceServer::start(bool finalisation)
 {
@@ -56,24 +56,26 @@
   {
     _config->finaliser = resource_same_thread_finaliser;
     _config->notifications = 1;
+    _config->auto_deletion = 1;
   }
 
   return resource_start_config(_config, _resource);
 }
 
-/* Start serving a resource in an existing thread. */
+/* Start serving a resource in an existing thread. The resource will not be
+   finalised. */
 
-long ResourceServer::start_in_thread(l4_cap_idx_t thread, bool finalisation)
+long ResourceServer::start_in_thread(l4_cap_idx_t thread)
 {
   resource_init_config(_config, _resource);
-  resource_set_config_threaded(_config, thread, 1, finalisation);
+  resource_set_config_threaded(_config, thread, 1, 0, 0);
 
   return resource_start_config(_config, _resource);
 }
 
 /* Start serving a resource in a new thread. */
 
-long ResourceServer::start_thread(bool finalisation)
+long ResourceServer::start_thread(bool finalisation, bool auto_deletion)
 {
   pthread_t thread;
   pthread_attr_t attr;
@@ -88,7 +90,8 @@
   if (err)
     return err;
 
-  resource_set_config_threaded(_config, pthread_l4_cap(thread), 1, finalisation);
+  resource_set_config_threaded(_config, pthread_l4_cap(thread), 1, finalisation,
+                               auto_deletion);
 
   return resource_start_config(_config, _resource);
 }
@@ -96,9 +99,10 @@
 /* A convenience method starting a thread and returning the server capability
    employed via the given parameter. */
 
-long ResourceServer::start_thread(l4_cap_idx_t *server, bool finalisation)
+long ResourceServer::start_thread(l4_cap_idx_t *server, bool finalisation,
+                                  bool auto_deletion)
 {
-  long err = start_thread(finalisation);
+  long err = start_thread(finalisation, auto_deletion);
 
   if (!err)
     *server = _config->server;
@@ -123,13 +127,16 @@
 /* Set a configuration to be threaded. */
 
 void resource_set_config_threaded(ipc_server_config_type *config,
-                                  l4_cap_idx_t thread, int new_thread,
-                                  int finalisation)
+                                  l4_cap_idx_t thread, int separate_thread,
+                                  int finalisation, int auto_deletion)
 {
-  config->finaliser = resource_thread_finaliser;
-  config->config_thread = new_thread;
+  if (finalisation)
+    config->finaliser = resource_thread_finaliser;
+
+  config->config_thread = separate_thread;
   config->thread = thread;
   config->notifications = finalisation;
+  config->auto_deletion = auto_deletion;
 }
 
 /* Activate a resource and start a server for it. */