Xnest: write through window properties to upstream server

Write through the window properties set by Xnest's client to the
upstream windows.

This is important for rootless mode.

Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>

hw/xnest/Screen.c

@@ -22,6 +22,7 @@ is" without express or implied warranty.
 
 #include <xcb/xcb_icccm.h>
 
+#include "dix/property_priv.h"
 #include "mi/mi_priv.h"
 
 #include "scrnintstr.h"
@@ -512,6 +513,8 @@ breakout:
                               &attributes);
     }
 
+    AddCallback(&PropertyStateCallback, xnest_property_state_callback, pScreen);
+
     if (!xnestCreateDefaultColormap(pScreen))
         return FALSE;
 

hw/xnest/meson.build

@@ -12,6 +12,7 @@ srcs = [
     'Keyboard.c',
     'Pixmap.c',
     'Pointer.c',
+    'properties.c',
     'Screen.c',
     'Window.c',
     '../../mi/miinitext.c',

hw/xnest/properties.c

@@ -0,0 +1,112 @@
+/* SPDX-License-Identifier: MIT OR X11
+ *
+ * Copyright © 2024 Enrico Weigelt, metux IT consult <info@metux.net>
+ *
+ * @brief property management functions
+ */
+#include <dix-config.h>
+
+#include "dix/dix_priv.h"
+#include "dix/property_priv.h"
+#include "include/propertyst.h"
+#include "include/windowstr.h"
+
+#include "xnest-xcb.h"
+
+#include "Drawable.h"
+
+static xcb_atom_t xnest_xlate_atom(struct xnest_upstream_info *upstream, ATOM outAtom)
+{
+    return xnest_intern_atom(upstream->conn, NameForAtom(outAtom));
+}
+
+static xcb_window_t xnest_xlate_window(Window window)
+{
+    WindowPtr pWin = dixLookupWindowByXID(window);
+    return (pWin ? xnestWindow(pWin) : 0);
+}
+
+static void xnest_property_xlate(ScreenPtr pScreen, PropertyStateRec *rec, void *dataBuf)
+{
+    // must translate
+    switch (rec->prop->type) {
+        /* nothing to do for these */
+        case XCB_ATOM_STRING:
+        case XCB_ATOM_INTEGER:
+        case XCB_ATOM_POINT:
+        case XCB_ATOM_RECTANGLE:
+        case XCB_ATOM_WM_SIZE_HINTS:
+        case XCB_ATOM_CARDINAL:
+        case XCB_ATOM_WM_HINTS:
+            return;
+
+        case XCB_ATOM_ATOM:
+        {
+            xcb_atom_t *atoms = dataBuf;
+            for (int x=0; x<rec->prop->size; x++)
+                atoms[x] = xnest_xlate_atom(&xnestUpstreamInfo, atoms[x]);
+            return;
+        }
+
+        case XCB_ATOM_WINDOW:
+        {
+            xcb_window_t *windows = dataBuf;
+            for (int x=0; x<rec->prop->size; x++)
+                windows[x] = xnest_xlate_window(windows[x]);
+            return;
+        }
+    }
+
+    const char *atomName = NameForAtom(rec->prop->type);
+    if (strcmp(atomName, "UTF8_STRING")==0)
+        return;
+    if (strcmp(atomName, "_MOTIF_DRAG_RECEIVER_INFO")==0)
+        return;
+
+    fprintf(stderr, "WARN: unknown atom type %s\n", atomName);
+}
+
+static void xnest_property_xlate_set(ScreenPtr pScreen, PropertyStateRec *rec)
+{
+    void *dataBuf = calloc(rec->prop->format, rec->prop->size);
+    if (!dataBuf)
+        return;
+
+    memcpy(dataBuf, rec->prop->data, (rec->prop->format / 8) * rec->prop->size);
+
+    xnest_property_xlate(pScreen, rec, dataBuf);
+
+    xnest_upstream_set_property(&xnestUpstreamInfo,
+                                xnestWindow(rec->win),
+                                NameForAtom(rec->prop->propertyName),
+                                NameForAtom(rec->prop->type),
+                                rec->state,
+                                rec->prop->format,
+                                rec->prop->size,
+                                dataBuf);
+
+    free(dataBuf);
+}
+
+void xnest_property_state_callback(CallbackListPtr *pcbl, void *closure, void *calldata)
+{
+    ScreenPtr pScreen = closure;
+    PropertyStateRec *rec = calldata;
+
+    if (rec->win->drawable.pScreen != pScreen)
+        return;
+
+    if (rec->state == PropertyNewValue) {
+        xnest_property_xlate_set(pScreen, rec);
+        return;
+    }
+
+    xnest_upstream_set_property(&xnestUpstreamInfo,
+                                xnestWindow(rec->win),
+                                NameForAtom(rec->prop->propertyName),
+                                NameForAtom(rec->prop->type),
+                                rec->state,
+                                rec->prop->format,
+                                rec->prop->size,
+                                rec->prop->data);
+}

hw/xnest/xnest-xcb.h

@@ -117,4 +117,6 @@ void xnest_upstream_set_property(
     uint32_t size,
     void *data);
 
+void xnest_property_state_callback(CallbackListPtr *pcbl, void *closure, void *calldata);
+
 #endif /* __XNEST__XCB_H */