ofonod: keep VoiceCallManager published across imsd restarts; enable on install

GNOME Calls 50.0 builds one origin per appearance of the modem's
VoiceCallManager interface and never disconnects a removed origin's
CallAdded handler, so every withdraw/re-add cycle leaves a stale handler
behind: calls announced twice after one cycle, a SIGBUS on freed memory
after a few (measured on a Fairphone 6). Withdrawing the interface on
every imsd restart or registration drop therefore cost the only incoming
call path on Phosh, where Calls runs as the session's daemon.

List the interface permanently. Registration is reported through the
modem's Online property and enforced in Dial, which now fails with
"imsd is not registered" or "imsd is not running". Only this daemon's own
restart (org.ofono vanishing) still cycles the origin, and the README says
to restart Calls after that.

Installing the opt-in imsd-ofono subpackage now enables imsd-ofonod (a
systemd preset plus the wants symlink, like imsd.service in the main
package), and imsd-dialerd's autostart is limited to KDE so a Phosh
session does not run the Plasma shim.

Verified on the FP6 under Phosh with GNOME Calls' autostarted daemon:
outgoing call, incoming call answered on the lock screen, then an imsd
restart under the running Calls (Online changes only, no origin cycle)
followed by another incoming call added once and answered.

Makefile

@@ -145,6 +145,8 @@ install: all
 	    $(DESTDIR)$(PREFIX)/share/dbus-1/system.d/imsd-ofono.conf
 	install -Dm644 packaging/90_imsd-ofono.gschema.override \
 	    $(DESTDIR)$(PREFIX)/share/glib-2.0/schemas/90_imsd-ofono.gschema.override
+	install -Dm644 packaging/80-imsd-ofono.preset \
+	    $(DESTDIR)$(PREFIX)/lib/systemd/system-preset/80-imsd-ofono.preset
 
 $(PCM) $(OBJ) $(O)/tests:
 	mkdir -p $@

README.md

@@ -173,8 +173,8 @@ private headers that no distro installs.
 Setup:
 
 ```sh
-apk add imsd-ofono                    # or install the files by hand
+apk add imsd-ofono                    # enables imsd-ofonod via a systemd preset
-systemctl enable --now imsd-ofonod    # system service; org.ofono is a system name
+systemctl enable --now imsd-ofonod    # hand installs: system service, org.ofono is a system name
 # point Calls at the ofono provider (the package ships this as a gschema
 # override; this is the per-user equivalent)
 gsettings set org.gnome.Calls autoload-plugins "['ofono']"
@@ -218,13 +218,17 @@ Known gaps, all inherited rather than introduced:
   normal dialpad is unaffected — that reaches imsd's own classifier.
 - DTMF is forwarded to imsd, where `SendDtmf` is still a stub (RFC 4733 is not
   implemented yet) — the same limitation Plasma has.
-- **Restart GNOME Calls after restarting `imsd-ofonod` (or imsd).** When the
+- **Restart GNOME Calls after restarting `imsd-ofonod` itself.** When the
   modem's `VoiceCallManager` interface goes away and comes back, Calls 50.0
   adds a new origin but leaves the old origin's `CallAdded` handler connected:
   after one such cycle every call is added twice, after a few the stale handler
   runs on freed memory and Calls dies with SIGBUS in `g_hash_table_lookup`
   (measured on the FP6). Calls-side; an upstream fix belongs in
-  `plugins/provider/ofono/calls-ofono-provider.c`.
+  `plugins/provider/ofono/calls-ofono-provider.c`. To keep imsd's own
+  restarts and registration drops from triggering it, `imsd-ofonod` lists the
+  interface permanently: `Online` tracks registration, and `Dial` fails with
+  "imsd is not registered" / "imsd is not running" instead. Only `org.ofono`
+  vanishing — this daemon restarting — still cycles the origin.
 
 Development, without a phone or root:
 

implementations/ofonod.cpp

@@ -23,9 +23,15 @@ D-Bus seam a third party can implement.
 Consumer-shaped details, verified against calls 50.0
 plugins/provider/ofono/ — get these wrong and the plugin silently ignores us:
   - the provider watches `org.ofono` on the SYSTEM bus and proxies `/` as
-    org.ofono.Manager. A modem becomes a dialable Origin only while its
+    org.ofono.Manager. A modem is an Origin exactly while its `Interfaces`
-    `Interfaces` property contains "org.ofono.VoiceCallManager", so that list
+    property lists "org.ofono.VoiceCallManager" — and Calls 50.0 never
-    is our registration gate — the analogue of the dialerd's deviceUniList.
+    disconnects a removed Origin's CallAdded handler, so every withdraw/
+    re-add cycle leaves a stale handler behind (calls announced twice, then
+    a crash on freed memory; measured on the FP6). The interface is
+    therefore listed PERMANENTLY; registration is reported through the
+    modem's `Online` property and enforced in Dial, which fails legibly
+    while imsd is down or unregistered. Only this daemon's own restart
+    (org.ofono vanishing) still cycles the Origin.
   - VoiceCall `State` strings are parsed as CallsCallState enum nicks:
     dialing / alerting / incoming / active / held / disconnected. imsd's
     "ringing" (a 180 from the far end) is oFono's "alerting".
@@ -159,12 +165,13 @@ GVariant* PropChanged(const char* name, GVariant* value) {
 // ---- Modem / VoiceCallManager properties ------------------------------------
 bool VoiceUp() { return ImsdUp && Registered; }
 
-// The registration gate: the plugin only builds an Origin while
+// Listed unconditionally: the plugin builds one Origin per appearance of
-// org.ofono.VoiceCallManager is listed here.
+// this interface and cannot survive a re-appearance (header). Whether calls
+// can actually be placed is VoiceUp(), checked in Dial and shown as Online.
 GVariant* InterfacesValue() {
     GVariantBuilder b;
     g_variant_builder_init(&b, G_VARIANT_TYPE("as"));
-    if (VoiceUp()) g_variant_builder_add(&b, "s", VcmIface);
+    g_variant_builder_add(&b, "s", VcmIface);
     return g_variant_builder_end(&b);
 }
 
@@ -534,7 +541,7 @@ void HandleVcmMethod(GDBusConnection*, const gchar*, const gchar*, const gchar*,
             return;
         }
         if (!VoiceUp()) {
-            g_dbus_method_invocation_return_dbus_error(inv, ErrFailed, "imsd is not registered");
+            g_dbus_method_invocation_return_dbus_error(inv, ErrFailed, ImsdUp ? "imsd is not registered" : "imsd is not running");
             return;
         }
         Log(std::format("Dial({})", number));
@@ -594,11 +601,10 @@ const GDBusInterfaceVTable VcmVtable = { HandleVcmMethod, nullptr, nullptr, {} }
 const GDBusInterfaceVTable SsVtable = { HandleSsMethod, nullptr, nullptr, {} };
 
 // ---- imsd events ------------------------------------------------------------
-void PublishInterfaces() {
+void PublishVoiceState() {
-    Emit(ModemPath, ModemIface, "PropertyChanged", PropChanged("Interfaces", InterfacesValue()));
     Emit(ModemPath, ModemIface, "PropertyChanged",
          PropChanged("Online", g_variant_new_boolean(VoiceUp() ? TRUE : FALSE)));
-    Log(std::format("voice interface {}", VoiceUp() ? "available" : "withdrawn"));
+    Log(std::format("voice {}", VoiceUp() ? "registered" : (ImsdUp ? "unregistered" : "unavailable (imsd down)")));
 }
 
 void OnImsdSignal(GDBusConnection*, const gchar*, const gchar*, const gchar*, const gchar* signal, GVariant* params, gpointer) {
@@ -640,7 +646,7 @@ void OnImsdSignal(GDBusConnection*, const gchar*, const gchar*, const gchar*, co
         g_variant_get(params, "(b)", &reg);
         if (Registered == static_cast<bool>(reg)) return;
         Registered = reg;
-        PublishInterfaces();
+        PublishVoiceState();
     }
 }
 
@@ -679,7 +685,7 @@ void OnImsdAppeared(GDBusConnection*, const gchar*, const gchar*, gpointer) {
     ImsdUp = true;
     Log("imsd up");
     RefreshFromImsd();
-    PublishInterfaces();
+    PublishVoiceState();
 }
 
 void OnImsdVanished(GDBusConnection*, const gchar*, gpointer) {
@@ -690,7 +696,7 @@ void OnImsdVanished(GDBusConnection*, const gchar*, gpointer) {
     std::vector<std::string> live;
     for (const auto& [uni, rec] : Calls) live.push_back(uni);
     for (const std::string& uni : live) RemoveCall(uni, "network");
-    PublishInterfaces();
+    PublishVoiceState();
 }
 
 gboolean OnTerm(gpointer loop) {

packaging/80-imsd-ofono.preset

@@ -0,0 +1,5 @@
+# SPDX-License-Identifier: GPL-3.0-only
+# SPDX-FileCopyrightText: Copyright (C) 2026 Catcrafts®
+# imsd-ofono is the opt-in GNOME Calls backend: installing it is the choice
+# to run it (the unit itself refuses to coexist with a real ofonod).
+enable imsd-ofonod.service

packaging/APKBUILD

@@ -46,4 +46,9 @@ ofono() {
 	amove usr/lib/systemd/system/imsd-ofonod.service
 	amove usr/share/dbus-1/system.d/imsd-ofono.conf
 	amove usr/share/glib-2.0/schemas/90_imsd-ofono.gschema.override
+	amove usr/lib/systemd/system-preset/80-imsd-ofono.preset
+	# enabled on install, like imsd.service in the main package
+	mkdir -p "$subpkgdir"/etc/systemd/system/multi-user.target.wants
+	ln -s /usr/lib/systemd/system/imsd-ofonod.service \
+		"$subpkgdir"/etc/systemd/system/multi-user.target.wants/imsd-ofonod.service
 }

packaging/APKBUILD.binary

@@ -70,6 +70,8 @@ package() {
         "$pkgdir"/usr/share/dbus-1/system.d/imsd-ofono.conf
     install -Dm644 90_imsd-ofono.gschema.override \
         "$pkgdir"/usr/share/glib-2.0/schemas/90_imsd-ofono.gschema.override
+    install -Dm644 80-imsd-ofono.preset \
+        "$pkgdir"/usr/lib/systemd/system-preset/80-imsd-ofono.preset
 }
 
 ofono() {
@@ -79,6 +81,11 @@ ofono() {
     amove usr/lib/systemd/system/imsd-ofonod.service
     amove usr/share/dbus-1/system.d/imsd-ofono.conf
     amove usr/share/glib-2.0/schemas/90_imsd-ofono.gschema.override
+    amove usr/lib/systemd/system-preset/80-imsd-ofono.preset
+    # enabled on install, like imsd.service in the main package
+    mkdir -p "$subpkgdir"/etc/systemd/system/multi-user.target.wants
+    ln -s /usr/lib/systemd/system/imsd-ofonod.service \
+        "$subpkgdir"/etc/systemd/system/multi-user.target.wants/imsd-ofonod.service
 }
 
 systemd() {

packaging/imsd-dialerd.desktop

@@ -7,5 +7,6 @@ Comment=Plasma Dialer backend for imsd (replaces plasma-dialer's modem-daemon)
 Exec=/usr/bin/imsd-dialerd
 Icon=call-start
 NoDisplay=true
+OnlyShowIn=KDE;
 X-KDE-autostart-phase=1
 X-KDE-StartupNotify=false

packaging/make-bin-tarball.sh

@@ -27,6 +27,7 @@ cp "$OFONOD" "$stage/imsd-$VER/imsd-ofonod"
 cp packaging/ims-pdn-up.sh packaging/imsd.service \
    packaging/imsd-dialerd.desktop packaging/imsd-ofonod.service \
    packaging/org.ofono.conf packaging/90_imsd-ofono.gschema.override \
+   packaging/80-imsd-ofono.preset \
    packaging/net.catcrafts.IMS1.conf "$stage/imsd-$VER/"
 tar -C "$stage" -czf "imsd-$VER.tar.gz" "imsd-$VER"
 echo "wrote imsd-$VER.tar.gz ($(du -h "imsd-$VER.tar.gz" | cut -f1))"