scanner: Guard interface declarations

This allows to include client and server headers in the same file
fixing warnings like

In file included from ../subprojects/wlroots/include/wlr/types/wlr_layer_shell_v1.h:16,
                 from ../src/desktop.h:16,
                 from ../src/server.h:13,
                 from ../tests/testlib.c:8:
tests/59830eb@@footest@sta/wlr-layer-shell-unstable-v1-protocol.h:80:34: warning: redundant redeclaration of ‘zwlr_layer_shell_v1_interface’ [-Wredundant-decls]
   80 | extern const struct wl_interface zwlr_layer_shell_v1_interface;
      |                                  ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
In file included from ../tests/testlib.h:8,
                 from ../tests/testlib.c:7:
tests/59830eb@@footest@sta/wlr-layer-shell-unstable-v1-client-protocol.h:77:34: note: previous declaration of ‘zwlr_layer_shell_v1_interface’ was here
   77 | extern const struct wl_interface zwlr_layer_shell_v1_interface;
      |                                  ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
In file included from ../subprojects/wlroots/include/wlr/types/wlr_layer_shell_v1.h:16,
                 from ../src/desktop.h:16,
                 from ../src/server.h:13,
                 from ../tests/testlib.c:8:
tests/59830eb@@footest@sta/wlr-layer-shell-unstable-v1-protocol.h:106:34: warning: redundant redeclaration of ‘zwlr_layer_surface_v1_interface’ [-Wredundant-decls]
  106 | extern const struct wl_interface zwlr_layer_surface_v1_interface;
      |                                  ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
In file included from ../tests/testlib.h:8,
                 from ../tests/testlib.c:7:
tests/59830eb@@footest@sta/wlr-layer-shell-unstable-v1-client-protocol.h:103:34: note: previous declaration of ‘zwlr_layer_surface_v1_interface’ was here
  103 | extern const struct wl_interface zwlr_layer_surface_v1_interface;

Signed-off-by: Guido Günther <agx@sigxcpu.org>
Closes: #158

1 files changed, 66 insertions, 0 deletions

diff --git a/tests/data/example-server.h b/tests/data/example-server.h
index adfc973..3311c5d 100644
--- a/tests/data/example-server.h
+++ b/tests/data/example-server.h
@@ -91,6 +91,8 @@ struct wl_subsurface;
 struct wl_surface;
 struct wl_touch;
 
+#ifndef WL_DISPLAY_INTERFACE
+#define WL_DISPLAY_INTERFACE
 /**
  * @page page_iface_wl_display wl_display
  * @section page_iface_wl_display_desc Description
@@ -107,6 +109,9 @@ struct wl_touch;
  * is used for internal Wayland protocol features.
  */
 extern const struct wl_interface wl_display_interface;
+#endif
+#ifndef WL_REGISTRY_INTERFACE
+#define WL_REGISTRY_INTERFACE
 /**
  * @page page_iface_wl_registry wl_registry
  * @section page_iface_wl_registry_desc Description
@@ -159,6 +164,9 @@ extern const struct wl_interface wl_display_interface;
  * the object.
  */
 extern const struct wl_interface wl_registry_interface;
+#endif
+#ifndef WL_CALLBACK_INTERFACE
+#define WL_CALLBACK_INTERFACE
 /**
  * @page page_iface_wl_callback wl_callback
  * @section page_iface_wl_callback_desc Description
@@ -175,6 +183,9 @@ extern const struct wl_interface wl_registry_interface;
  * the related request is done.
  */
 extern const struct wl_interface wl_callback_interface;
+#endif
+#ifndef WL_COMPOSITOR_INTERFACE
+#define WL_COMPOSITOR_INTERFACE
 /**
  * @page page_iface_wl_compositor wl_compositor
  * @section page_iface_wl_compositor_desc Description
@@ -193,6 +204,9 @@ extern const struct wl_interface wl_callback_interface;
  * surfaces into one displayable output.
  */
 extern const struct wl_interface wl_compositor_interface;
+#endif
+#ifndef WL_SHM_POOL_INTERFACE
+#define WL_SHM_POOL_INTERFACE
 /**
  * @page page_iface_wl_shm_pool wl_shm_pool
  * @section page_iface_wl_shm_pool_desc Description
@@ -219,6 +233,9 @@ extern const struct wl_interface wl_compositor_interface;
  * a surface or for many small buffers.
  */
 extern const struct wl_interface wl_shm_pool_interface;
+#endif
+#ifndef WL_SHM_INTERFACE
+#define WL_SHM_INTERFACE
 /**
  * @page page_iface_wl_shm wl_shm
  * @section page_iface_wl_shm_desc Description
@@ -249,6 +266,9 @@ extern const struct wl_interface wl_shm_pool_interface;
  * that can be used for buffers.
  */
 extern const struct wl_interface wl_shm_interface;
+#endif
+#ifndef WL_BUFFER_INTERFACE
+#define WL_BUFFER_INTERFACE
 /**
  * @page page_iface_wl_buffer wl_buffer
  * @section page_iface_wl_buffer_desc Description
@@ -271,6 +291,9 @@ extern const struct wl_interface wl_shm_interface;
  * updates the contents is defined by the buffer factory interface.
  */
 extern const struct wl_interface wl_buffer_interface;
+#endif
+#ifndef WL_DATA_OFFER_INTERFACE
+#define WL_DATA_OFFER_INTERFACE
 /**
  * @page page_iface_wl_data_offer wl_data_offer
  * @section page_iface_wl_data_offer_desc Description
@@ -295,6 +318,9 @@ extern const struct wl_interface wl_buffer_interface;
  * data directly from the source client.
  */
 extern const struct wl_interface wl_data_offer_interface;
+#endif
+#ifndef WL_DATA_SOURCE_INTERFACE
+#define WL_DATA_SOURCE_INTERFACE
 /**
  * @page page_iface_wl_data_source wl_data_source
  * @section page_iface_wl_data_source_desc Description
@@ -315,6 +341,9 @@ extern const struct wl_interface wl_data_offer_interface;
  * to requests to transfer the data.
  */
 extern const struct wl_interface wl_data_source_interface;
+#endif
+#ifndef WL_DATA_DEVICE_INTERFACE
+#define WL_DATA_DEVICE_INTERFACE
 /**
  * @page page_iface_wl_data_device wl_data_device
  * @section page_iface_wl_data_device_desc Description
@@ -337,6 +366,9 @@ extern const struct wl_interface wl_data_source_interface;
  * mechanisms such as copy-and-paste and drag-and-drop.
  */
 extern const struct wl_interface wl_data_device_interface;
+#endif
+#ifndef WL_DATA_DEVICE_MANAGER_INTERFACE
+#define WL_DATA_DEVICE_MANAGER_INTERFACE
 /**
  * @page page_iface_wl_data_device_manager wl_data_device_manager
  * @section page_iface_wl_data_device_manager_desc Description
@@ -369,6 +401,9 @@ extern const struct wl_interface wl_data_device_interface;
  * wl_data_offer.accept and wl_data_offer.finish for details.
  */
 extern const struct wl_interface wl_data_device_manager_interface;
+#endif
+#ifndef WL_SHELL_INTERFACE
+#define WL_SHELL_INTERFACE
 /**
  * @page page_iface_wl_shell wl_shell
  * @section page_iface_wl_shell_desc Description
@@ -391,6 +426,9 @@ extern const struct wl_interface wl_data_device_manager_interface;
  * a basic surface.
  */
 extern const struct wl_interface wl_shell_interface;
+#endif
+#ifndef WL_SHELL_SURFACE_INTERFACE
+#define WL_SHELL_SURFACE_INTERFACE
 /**
  * @page page_iface_wl_shell_surface wl_shell_surface
  * @section page_iface_wl_shell_surface_desc Description
@@ -425,6 +463,9 @@ extern const struct wl_interface wl_shell_interface;
  * the wl_surface object.
  */
 extern const struct wl_interface wl_shell_surface_interface;
+#endif
+#ifndef WL_SURFACE_INTERFACE
+#define WL_SURFACE_INTERFACE
 /**
  * @page page_iface_wl_surface wl_surface
  * @section page_iface_wl_surface_desc Description
@@ -515,6 +556,9 @@ extern const struct wl_interface wl_shell_surface_interface;
  * switching is not allowed).
  */
 extern const struct wl_interface wl_surface_interface;
+#endif
+#ifndef WL_SEAT_INTERFACE
+#define WL_SEAT_INTERFACE
 /**
  * @page page_iface_wl_seat wl_seat
  * @section page_iface_wl_seat_desc Description
@@ -535,6 +579,9 @@ extern const struct wl_interface wl_surface_interface;
  * maintains a keyboard focus and a pointer focus.
  */
 extern const struct wl_interface wl_seat_interface;
+#endif
+#ifndef WL_POINTER_INTERFACE
+#define WL_POINTER_INTERFACE
 /**
  * @page page_iface_wl_pointer wl_pointer
  * @section page_iface_wl_pointer_desc Description
@@ -563,6 +610,9 @@ extern const struct wl_interface wl_seat_interface;
  * and scrolling.
  */
 extern const struct wl_interface wl_pointer_interface;
+#endif
+#ifndef WL_KEYBOARD_INTERFACE
+#define WL_KEYBOARD_INTERFACE
 /**
  * @page page_iface_wl_keyboard wl_keyboard
  * @section page_iface_wl_keyboard_desc Description
@@ -579,6 +629,9 @@ extern const struct wl_interface wl_pointer_interface;
  * associated with a seat.
  */
 extern const struct wl_interface wl_keyboard_interface;
+#endif
+#ifndef WL_TOUCH_INTERFACE
+#define WL_TOUCH_INTERFACE
 /**
  * @page page_iface_wl_touch wl_touch
  * @section page_iface_wl_touch_desc Description
@@ -607,6 +660,9 @@ extern const struct wl_interface wl_keyboard_interface;
  * contact point can be identified by the ID of the sequence.
  */
 extern const struct wl_interface wl_touch_interface;
+#endif
+#ifndef WL_OUTPUT_INTERFACE
+#define WL_OUTPUT_INTERFACE
 /**
  * @page page_iface_wl_output wl_output
  * @section page_iface_wl_output_desc Description
@@ -631,6 +687,9 @@ extern const struct wl_interface wl_touch_interface;
  * as global during start up, or when a monitor is hotplugged.
  */
 extern const struct wl_interface wl_output_interface;
+#endif
+#ifndef WL_REGION_INTERFACE
+#define WL_REGION_INTERFACE
 /**
  * @page page_iface_wl_region wl_region
  * @section page_iface_wl_region_desc Description
@@ -651,6 +710,9 @@ extern const struct wl_interface wl_output_interface;
  * regions of a surface.
  */
 extern const struct wl_interface wl_region_interface;
+#endif
+#ifndef WL_SUBCOMPOSITOR_INTERFACE
+#define WL_SUBCOMPOSITOR_INTERFACE
 /**
  * @page page_iface_wl_subcompositor wl_subcompositor
  * @section page_iface_wl_subcompositor_desc Description
@@ -701,6 +763,9 @@ extern const struct wl_interface wl_region_interface;
  * processing to dedicated overlay hardware when possible.
  */
 extern const struct wl_interface wl_subcompositor_interface;
+#endif
+#ifndef WL_SUBSURFACE_INTERFACE
+#define WL_SUBSURFACE_INTERFACE
 /**
  * @page page_iface_wl_subsurface wl_subsurface
  * @section page_iface_wl_subsurface_desc Description
@@ -811,6 +876,7 @@ extern const struct wl_interface wl_subcompositor_interface;
  * unmapped.
  */
 extern const struct wl_interface wl_subsurface_interface;
+#endif
 
 #ifndef WL_DISPLAY_ERROR_ENUM
 #define WL_DISPLAY_ERROR_ENUM