xdg: use timer based reset instead of window ID

This is required to remove the dependency on the window provider.

modules/misc/inhibit/xdg.c

@@ -26,6 +26,7 @@
 #include <vlc_plugin.h>
 #include <vlc_inhibit.h>
 #include <assert.h>
+#include <errno.h>
 #include <signal.h>
 #include <spawn.h>
 #include <sys/wait.h>
@@ -44,15 +45,43 @@ vlc_module_end ()
 
 struct vlc_inhibit_sys
 {
-    vlc_thread_t thread;
-    vlc_cond_t update, inactive;
-    vlc_mutex_t lock;
+    vlc_timer_t timer;
     posix_spawnattr_t attr;
-    bool suspend, suspended;
 };
 
-static void Inhibit (vlc_inhibit_t *ih, bool suspend);
-static void *Thread (void *);
+extern char **environ;
+
+static void Timer (void *data)
+{
+    vlc_inhibit_t *ih = data;
+    vlc_inhibit_sys_t *sys = ih->p_sys;
+    char *argv[3] = {
+        (char *)"xdg-screensaver", (char *)"reset", NULL
+    };
+    pid_t pid;
+
+    int err = posix_spawnp (&pid, "xdg-screensaver", NULL, &sys->attr,
+                            argv, environ);
+    if (err == 0)
+    {
+        int status;
+
+        while (waitpid (pid, &status, 0) == -1);
+    }
+    else
+    {
+        errno = err;
+        msg_Warn (ih, "error starting xdg-screensaver: %m");
+    }
+}
+
+static void Inhibit (vlc_inhibit_t *ih, bool suspend)
+{
+    vlc_inhibit_sys_t *sys = ih->p_sys;
+    mtime_t delay = suspend ? 30 * CLOCK_FREQ : INT64_C(0);
+
+    vlc_timer_schedule (sys->timer, false, delay, delay);
+}
 
 static int Open (vlc_object_t *obj)
 {
@@ -61,12 +90,6 @@ static int Open (vlc_object_t *obj)
     if (p_sys == NULL)
         return VLC_ENOMEM;
 
-    ih->p_sys = p_sys;
-    ih->inhibit = Inhibit;
-
-    vlc_mutex_init (&p_sys->lock);
-    vlc_cond_init (&p_sys->update);
-    vlc_cond_init (&p_sys->inactive);
     posix_spawnattr_init (&p_sys->attr);
     /* Reset signal handlers to default and clear mask in the child process */
     {
@@ -79,17 +102,16 @@ static int Open (vlc_object_t *obj)
         posix_spawnattr_setflags (&p_sys->attr, POSIX_SPAWN_SETSIGDEF
                                               | POSIX_SPAWN_SETSIGMASK);
     }
-    p_sys->suspend = false;
-    p_sys->suspended = false;
 
-    if (vlc_clone (&p_sys->thread, Thread, ih, VLC_THREAD_PRIORITY_LOW))
+    ih->p_sys = p_sys;
+    if (vlc_timer_create (&p_sys->timer, Timer, ih))
     {
-        vlc_cond_destroy (&p_sys->inactive);
-        vlc_cond_destroy (&p_sys->update);
-        vlc_mutex_destroy (&p_sys->lock);
+        posix_spawnattr_destroy (&p_sys->attr);
         free (p_sys);
         return VLC_ENOMEM;
     }
+
+    ih->inhibit = Inhibit;
     return VLC_SUCCESS;
 }
 
@@ -98,80 +120,7 @@ static void Close (vlc_object_t *obj)
     vlc_inhibit_t *ih = (vlc_inhibit_t *)obj;
     vlc_inhibit_sys_t *p_sys = ih->p_sys;
 
-    /* Make sure xdg-screensaver is gone for good */
-    vlc_mutex_lock (&p_sys->lock);
-    while (p_sys->suspended)
-        vlc_cond_wait (&p_sys->inactive, &p_sys->lock);
-    vlc_mutex_unlock (&p_sys->lock);
-
-    vlc_cancel (p_sys->thread);
-    vlc_join (p_sys->thread, NULL);
+    vlc_timer_destroy (p_sys->timer);
     posix_spawnattr_destroy (&p_sys->attr);
-    vlc_cond_destroy (&p_sys->inactive);
-    vlc_cond_destroy (&p_sys->update);
-    vlc_mutex_destroy (&p_sys->lock);
     free (p_sys);
 }
-
-static void Inhibit (vlc_inhibit_t *ih, bool suspend)
-{
-    vlc_inhibit_sys_t *p_sys = ih->p_sys;
-
-    /* xdg-screensaver can take quite a while to start up (e.g. 1 second).
-     * So we avoid _waiting_ for it unless we really need to (clean up). */
-    vlc_mutex_lock (&p_sys->lock);
-    p_sys->suspend = suspend;
-    vlc_cond_signal (&p_sys->update);
-    vlc_mutex_unlock (&p_sys->lock);
-}
-
-extern char **environ;
-
-VLC_NORETURN
-static void *Thread (void *data)
-{
-    vlc_inhibit_t *ih = data;
-    vlc_inhibit_sys_t *p_sys = ih->p_sys;
-    char id[11];
-
-    snprintf (id, sizeof (id), "0x%08"PRIx32, ih->window_id);
-
-    vlc_mutex_lock (&p_sys->lock);
-    mutex_cleanup_push (&p_sys->lock);
-    for (;;)
-    {   /* TODO: detach the thread, so we don't need one at all time */
-        while (p_sys->suspended == p_sys->suspend)
-            vlc_cond_wait (&p_sys->update, &p_sys->lock);
-
-        int canc = vlc_savecancel ();
-        char *argv[4] = {
-            (char *)"xdg-screensaver",
-            (char *)(p_sys->suspend ? "suspend" : "resume"),
-            id,
-            NULL,
-        };
-        pid_t pid;
-
-        vlc_mutex_unlock (&p_sys->lock);
-        if (!posix_spawnp (&pid, "xdg-screensaver", NULL, &p_sys->attr,
-                           argv, environ))
-        {
-            int status;
-
-            msg_Dbg (ih, "started xdg-screensaver (PID = %d)", (int)pid);
-            /* Wait for command to complete */
-            while (waitpid (pid, &status, 0) == -1);
-        }
-        else/* We don't handle the error, but busy looping would be worse :( */
-            msg_Warn (ih, "could not start xdg-screensaver");
-
-        vlc_mutex_lock (&p_sys->lock);
-        p_sys->suspended = p_sys->suspend;
-        if (!p_sys->suspended)
-            vlc_cond_signal (&p_sys->inactive);
-        vlc_restorecancel (canc);
-    }
-
-    vlc_cleanup_pop ();
-    assert (0);
-}