Add server_chansrv_in_use() to module interface

mc/mc.h

@@ -87,7 +87,8 @@ struct mod
                                   char *data, int data_len,
                                   int total_data_len, int flags);
     int (*server_bell_trigger)(struct mod *v);
-    tintptr server_dumby[100 - 25]; /* align, 100 minus the number of server
+    int (*server_chansrv_in_use)(struct mod *v);
+    tintptr server_dumby[100 - 26]; /* align, 100 minus the number of server
                                      functions above */
     /* common */
     tintptr handle; /* pointer to self as long */

neutrinordp/xrdp-neutrinordp.h

@@ -130,6 +130,7 @@ struct mod
                                   char *data, int data_len,
                                   int total_data_len, int flags);
     int (*server_bell_trigger)(struct mod *v);
+    int (*server_chansrv_in_use)(struct mod *v);
     /* off screen bitmaps */
     int (*server_create_os_surface)(struct mod *v, int rdpindex,
                                     int width, int height);
@@ -184,7 +185,7 @@ struct mod
                               int flags, int frame_id);
     int (*server_session_info)(struct mod *v, const char *data,
                                int data_bytes);
-    tintptr server_dumby[100 - 44]; /* align, 100 minus the number of server
+    tintptr server_dumby[100 - 45]; /* align, 100 minus the number of server
                                        functions above */
     /* common */
     tintptr handle; /* pointer to self as long */

vnc/vnc.h

@@ -125,7 +125,8 @@ struct vnc
                                   char *data, int data_len,
                                   int total_data_len, int flags);
     int (*server_bell_trigger)(struct vnc *v);
-    tintptr server_dumby[100 - 25]; /* align, 100 minus the number of server
+    int (*server_chansrv_in_use)(struct vnc *v);
+    tintptr server_dumby[100 - 26]; /* align, 100 minus the number of server
                                      functions above */
     /* common */
     tintptr handle; /* pointer to self as long */

xrdp/xrdp.h

@@ -413,6 +413,8 @@ server_end_update(struct xrdp_mod *mod);
 int
 server_bell_trigger(struct xrdp_mod *mod);
 int
+server_chansrv_in_use(struct xrdp_mod *mod);
+int
 server_fill_rect(struct xrdp_mod *mod, int x, int y, int cx, int cy);
 int
 server_screen_blt(struct xrdp_mod *mod, int x, int y, int cx, int cy,

xrdp/xrdp_mm.c

@@ -427,6 +427,7 @@ xrdp_mm_setup_mod1(struct xrdp_mm *self)
             self->mod->server_begin_update = server_begin_update;
             self->mod->server_end_update = server_end_update;
             self->mod->server_bell_trigger = server_bell_trigger;
+            self->mod->server_chansrv_in_use = server_chansrv_in_use;
             self->mod->server_fill_rect = server_fill_rect;
             self->mod->server_screen_blt = server_screen_blt;
             self->mod->server_paint_rect = server_paint_rect;
@@ -1628,8 +1629,6 @@ xrdp_mm_connect_chansrv(struct xrdp_mm *self, const char *ip, const char *port)
 {
     int index;
 
-    self->usechansrv = 1;
-
     if (self->wm->client_info->channels_allowed == 0)
     {
         LOG(LOG_LEVEL_DEBUG, "%s: "
@@ -2457,6 +2456,7 @@ xrdp_mm_connect(struct xrdp_mm *self)
             if (g_strcasecmp(value, "-1") == 0)
             {
                 self->sesman_controlled = 1;
+                self->usechansrv = 1;
             }
         }
 
@@ -3004,6 +3004,17 @@ server_bell_trigger(struct xrdp_mod *mod)
     return 0;
 }
 
+/*****************************************************************************/
+/* Chansrv in use on this configuration? */
+int
+server_chansrv_in_use(struct xrdp_mod *mod)
+{
+    struct xrdp_wm *wm;
+
+    wm = (struct xrdp_wm *)(mod->wm);
+    return wm->mm->usechansrv;
+}
+
 
 /*****************************************************************************/
 int
@@ -3610,14 +3621,13 @@ server_send_to_channel(struct xrdp_mod *mod, int channel_id,
 
     if (wm->mm->usechansrv)
     {
-        /*
+        /* Modules should not be calling this if chansrv is running -
-         * Xvnc backend reaches here
+         * they can use server_chansrv_in_use() to avoid doing this */
-         * should not return 1 as this case is not an error
+        LOG_DEVEL(LOG_LEVEL_ERROR,
-         */
+                  "Bad call of server_send_to_channel() detected");
-        return 0;
+        return 1;
     }
 
-    /* vnc proxy mode reaches here */
     return libxrdp_send_to_channel(wm->session, channel_id, data, data_len,
                                    total_data_len, flags);
 }

xrdp/xrdp_types.h

@@ -103,6 +103,7 @@ struct xrdp_mod
                                   char *data, int data_len,
                                   int total_data_len, int flags);
     int (*server_bell_trigger)(struct xrdp_mod *v);
+    int (*server_chansrv_in_use)(struct xrdp_mod *v);
     /* off screen bitmaps */
     int (*server_create_os_surface)(struct xrdp_mod *v, int rdpindex,
                                     int width, int height);
@@ -158,7 +159,7 @@ struct xrdp_mod
                               int flags, int frame_id);
     int (*server_session_info)(struct xrdp_mod *v, const char *data,
                                int data_bytes);
-    tintptr server_dumby[100 - 44]; /* align, 100 minus the number of server
+    tintptr server_dumby[100 - 45]; /* align, 100 minus the number of server
                                      functions above */
     /* common */
     tintptr handle; /* pointer to self as int */

xup/xup.h

@@ -100,6 +100,7 @@ struct mod
                                   char *data, int data_len,
                                   int total_data_len, int flags);
     int (*server_bell_trigger)(struct mod *v);
+    int (*server_chansrv_in_use)(struct mod *v);
     /* off screen bitmaps */
     int (*server_create_os_surface)(struct mod *v, int rdpindex,
                                     int width, int height);
@@ -151,7 +152,7 @@ struct mod
                               char *data, int width, int height,
                               int flags, int frame_id);
 
-    tintptr server_dumby[100 - 43]; /* align, 100 minus the number of server
+    tintptr server_dumby[100 - 44]; /* align, 100 minus the number of server
                                      functions above */
     /* common */
     tintptr handle; /* pointer to self as long */