[Spice-devel] [PATCH vdagent v3 2/3] retrieve _NET_WM_NAME using GDK

[Jakub Janků]

Get _NET_WM_NAME using gdk_x11_screen_get_window_manager_name().
vdagent_x11_get_wm_name(): return the name instead of setting it.
Return string specifics:
- "unsupported", when not running on X11
- "unknown", when the name cannot be retrieved
Since the return value is never NULL, remove obsolete checks.
---
 src/vdagent/x11.c | 88 +++++++++++++------------------------------------------
 1 file changed, 21 insertions(+), 67 deletions(-)

diff --git a/src/vdagent/x11.c b/src/vdagent/x11.c
index 6e47ea1..4ea86e9 100644
--- a/src/vdagent/x11.c
+++ b/src/vdagent/x11.c
@@ -32,6 +32,10 @@
    pending writes are flushed. */
 
 #include <glib.h>
+#include <gdk/gdk.h>
+#ifdef GDK_WINDOWING_X11
+#include <gdk/gdkx.h>
+#endif
 #include <stdlib.h>
 #include <limits.h>
 #include <string.h>
@@ -111,66 +115,16 @@ int vdagent_x11_restore_error_handler(struct vdagent_x11 *x11)
     return error;
 }
 
-static void vdagent_x11_get_wm_name(struct vdagent_x11 *x11)
+static const gchar *vdagent_x11_get_wm_name()
 {
-    Atom type_ret;
-    int format_ret;
-    unsigned long len, remain;
-    unsigned char *data = NULL;
-    Window sup_window = None;
-
-    /* XGetWindowProperty can throw a BadWindow error. One way we can trigger
-       this is when the display-manager (ie gdm) has set, and not cleared the
-       _NET_SUPPORTING_WM_CHECK property, and the window manager running in
-       the user session has not yet updated it to point to its window, so its
-       pointing to a nonexistent window. */
-    vdagent_x11_set_error_handler(x11, vdagent_x11_ignore_bad_window_handler);
-
-    /* Get the window manager SUPPORTING_WM_CHECK window */
-    if (XGetWindowProperty(x11->display, x11->root_window[0],
-            XInternAtom(x11->display, "_NET_SUPPORTING_WM_CHECK", False), 0,
-            LONG_MAX, False, XA_WINDOW, &type_ret, &format_ret, &len,
-            &remain, &data) == Success) {
-        if (type_ret == XA_WINDOW)
-            sup_window = *((Window *)data);
-        XFree(data);
-    }
-    if (sup_window == None &&
-        XGetWindowProperty(x11->display, x11->root_window[0],
-            XInternAtom(x11->display, "_WIN_SUPPORTING_WM_CHECK", False), 0,
-            LONG_MAX, False, XA_CARDINAL, &type_ret, &format_ret, &len,
-            &remain, &data) == Success) {
-        if (type_ret == XA_CARDINAL)
-            sup_window = *((Window *)data);
-        XFree(data);
-    }
-    /* So that we can get the net_wm_name */
-    if (sup_window != None) {
-        Atom utf8 = XInternAtom(x11->display, "UTF8_STRING", False);
-        if (XGetWindowProperty(x11->display, sup_window,
-                XInternAtom(x11->display, "_NET_WM_NAME", False), 0,
-                LONG_MAX, False, utf8, &type_ret, &format_ret, &len,
-                &remain, &data) == Success) {
-            if (type_ret == utf8) {
-                x11->net_wm_name =
-                    g_strndup((char *)data, (format_ret / 8) * len);
-            }
-            XFree(data);
-        }
-        if (x11->net_wm_name == NULL &&
-            XGetWindowProperty(x11->display, sup_window,
-                XInternAtom(x11->display, "_NET_WM_NAME", False), 0,
-                LONG_MAX, False, XA_STRING, &type_ret, &format_ret, &len,
-                &remain, &data) == Success) {
-            if (type_ret == XA_STRING) {
-                x11->net_wm_name =
-                    g_strndup((char *)data, (format_ret / 8) * len);
-            }
-            XFree(data);
-        }
-    }
-
-    vdagent_x11_restore_error_handler(x11);
+#ifdef GDK_WINDOWING_X11
+    GdkDisplay *display = gdk_display_get_default();
+    if (GDK_IS_X11_DISPLAY(display))
+        return gdk_x11_screen_get_window_manager_name(
+            gdk_display_get_default_screen(display));
+    else
+#endif
+    return "unsupported";
 }
 
 struct vdagent_x11 *vdagent_x11_create(struct udscs_connection *vdagentd,
@@ -278,12 +232,13 @@ struct vdagent_x11 *vdagent_x11_create(struct udscs_connection *vdagentd,
     /* Get net_wm_name, since we are started at the same time as the wm,
        sometimes we need to wait a bit for it to show up. */
     i = 10;
-    vdagent_x11_get_wm_name(x11);
-    while (x11->net_wm_name == NULL && --i > 0) {
+    x11->net_wm_name = (gchar *)vdagent_x11_get_wm_name();
+    while (!strcmp(x11->net_wm_name, "unknown") && --i > 0) {
         usleep(100000);
-        vdagent_x11_get_wm_name(x11);
+        x11->net_wm_name = (gchar *)vdagent_x11_get_wm_name();
     }
-    if (x11->debug && x11->net_wm_name)
+    x11->net_wm_name = g_strdup(x11->net_wm_name);
+    if (x11->debug)
         syslog(LOG_DEBUG, "net_wm_name: \"%s\", has icons: %d",
                x11->net_wm_name, vdagent_x11_has_icons_on_desktop(x11));
 
@@ -1347,10 +1302,9 @@ int vdagent_x11_has_icons_on_desktop(struct vdagent_x11 *x11)
     };
     int i;
 
-    if (x11->net_wm_name)
-        for (i = 0; wms_with_icons_on_desktop[i]; i++)
-            if (!strcmp(x11->net_wm_name, wms_with_icons_on_desktop[i]))
-                return 1;
+    for (i = 0; wms_with_icons_on_desktop[i]; i++)
+        if (!strcmp(x11->net_wm_name, wms_with_icons_on_desktop[i]))
+            return 1;
 
     return 0;
 }
-- 
2.13.6