MIR: Add better error handling for a failed connection

src/video/mir/SDL_mirsym.h

@@ -56,7 +56,7 @@ SDL_MIR_SYM(void,mir_surface_spec_set_state,(MirSurfaceSpec *spec, MirSurfaceSta
 SDL_MIR_SYM(void,mir_surface_apply_spec,(MirSurface *surface, MirSurfaceSpec *spec))
 SDL_MIR_SYM(void,mir_surface_get_parameters,(MirSurface *surface, MirSurfaceParameters *params))
 SDL_MIR_SYM(MirBufferStream*,mir_surface_get_buffer_stream,(MirSurface *surface))
-SDL_MIR_SYM(MirCursorConfiguration*,mir_cursor_configuration_from_buffer_stream,(MirBufferStream* stream, int hot_x, int hot_y))
+SDL_MIR_SYM(MirCursorConfiguration*,mir_cursor_configuration_from_buffer_stream,(MirBufferStream const* stream, int hot_x, int hot_y))
 SDL_MIR_SYM(MirBufferStream*,mir_connection_create_buffer_stream_sync,(MirConnection *connection, int w, int h, MirPixelFormat format, MirBufferUsage usage))
 SDL_MIR_SYM(MirKeyboardAction,mir_keyboard_event_action,(MirKeyboardEvent const *event))
 SDL_MIR_SYM(xkb_keysym_t,mir_keyboard_event_key_code,(MirKeyboardEvent const *event))
@@ -94,6 +94,7 @@ SDL_MIR_SYM(void,mir_cursor_configuration_destroy,(MirCursorConfiguration* conf)
 SDL_MIR_SYM(void,mir_wait_for,(MirWaitHandle* handle))
 SDL_MIR_SYM(int,mir_resize_event_get_width,(MirResizeEvent const* resize_event))
 SDL_MIR_SYM(int,mir_resize_event_get_height,(MirResizeEvent const* resize_event))
+SDL_MIR_SYM(char const*,mir_connection_get_error_message,(MirConnection* connection))
 
 SDL_MIR_SYM_CONST(char const*,mir_omnidirectional_resize_cursor_name)
 SDL_MIR_SYM_CONST(char const*,mir_busy_cursor_name)

src/video/mir/SDL_mirvideo.c

@@ -277,8 +277,10 @@ MIR_VideoInit(_THIS)
     mir_data->software       = SDL_FALSE;
     mir_data->pixel_format   = mir_pixel_format_invalid;
 
-    if (!MIR_mir_connection_is_valid(mir_data->connection))
-        return SDL_SetError("Failed to connect to the Mir Server");
+    if (!MIR_mir_connection_is_valid(mir_data->connection)) {
+        return SDL_SetError("Failed to connect to the mir server: %s",
+            MIR_mir_connection_get_error_message(mir_data->connection));
+    }
 
     MIR_InitDisplays(_this);
     MIR_InitMouse();

src/video/mir/SDL_mirwindow.c

@@ -130,8 +130,8 @@ MIR_CreateWindow(_THIS, SDL_Window* window)
     MIR_mir_surface_spec_release(spec);
 
     if (!MIR_mir_surface_is_valid(mir_window->surface)) {
-        const char* error = MIR_mir_surface_get_error_message(mir_window->surface);
-        return SDL_SetError("Failed to created a mir surface: %s", error);
+        return SDL_SetError("Failed to created a mir surface: %s",
+            MIR_mir_surface_get_error_message(mir_window->surface));
     }
 
     if (window->flags & SDL_WINDOW_OPENGL) {