fix: stabilize Treeland VT session switching

debian/control

@@ -23,7 +23,7 @@ Provides: x-display-manager
 Architecture: any
 Depends: ${shlibs:Depends},
          ${misc:Depends},
-         seatd,
+         dde-seatd,
          treeland,
          libpam-systemd,
 Description: a modern display manager for Wayland sessions aiming to be fast, simple and beautiful.

services/CMakeLists.txt

@@ -1,6 +1,11 @@
 configure_file(ddm.service.in ddm.service)
 install(FILES "${CMAKE_CURRENT_BINARY_DIR}/ddm.service" DESTINATION "${SYSTEMD_SYSTEM_UNIT_DIR}")
 
+configure_file(treeland-dde-seatd.conf.in treeland-dde-seatd.conf)
+install(FILES "${CMAKE_CURRENT_BINARY_DIR}/treeland-dde-seatd.conf"
+        DESTINATION "${SYSTEMD_SYSTEM_UNIT_DIR}/treeland.service.d"
+        RENAME 10-dde-seatd.conf)
+
 # systemd-tmpfiles can be used standalone without other systemd parts
 if(DEFINED SYSTEMD_TMPFILES_DIR)
     configure_file(ddm-tmpfiles.conf.in ddm-tmpfiles.conf)

services/ddm.service.in

@@ -2,13 +2,12 @@
 Description=Simple Desktop Display Manager
 Documentation=man:ddm(1) man:ddm.conf(5)
 Conflicts=getty@tty${DDM_INITIAL_VT}.service
-After=systemd-user-sessions.service getty@tty${DDM_INITIAL_VT}.service plymouth-quit.service systemd-logind.service
+After=systemd-user-sessions.service getty@tty${DDM_INITIAL_VT}.service plymouth-quit.service systemd-logind.service dde-seatd.service
 PartOf=graphical.target
 StartLimitIntervalSec=30
 StartLimitBurst=2
 
-Requires=seatd.service
-Before=seatd.service
+Requires=dde-seatd.service
 
 [Service]
 ExecStart=@CMAKE_INSTALL_FULL_BINDIR@/ddm

services/treeland-dde-seatd.conf.in

@@ -0,0 +1,9 @@
+[Unit]
+Requires=
+Requires=dde-seatd.service
+After=
+After=dde-seatd.service
+
+[Service]
+Environment=LIBSEAT_BACKEND=seatd
+Environment=SEATD_SOCK=/run/dde-seatd.sock

src/common/SignalHandler.cpp

@@ -110,6 +110,15 @@ namespace DDM {
             qCritical() << "Failed to set up " << strsignal(signal) << " handler.";
             return;
         }
+
+        sigset_t set;
+        sigemptyset(&set);
+        sigaddset(&set, signal);
+        if (sigprocmask(SIG_UNBLOCK, &set, nullptr) < 0) {
+            qCritical() << "Failed to unblock " << strsignal(signal) << " handler.";
+            return;
+        }
+
         customSignals.append(signal);
     }