Handle shaped windows

7 files changed, 134 insertions, 3 deletions

diff --git a/include/xcwm/event.h b/include/xcwm/event.h
index b146037..b18cf69 100644
--- a/include/xcwm/event.h
+++ b/include/xcwm/event.h
@@ -44,6 +44,7 @@ typedef enum xcwm_event_type_t {
     XCWM_EVENT_WINDOW_DESTROY,
     XCWM_EVENT_WINDOW_NAME,
     XCWM_EVENT_WINDOW_APPEARANCE,
+    XCWM_EVENT_WINDOW_SHAPE,
 } xcwm_event_type_t;
 
 /**
diff --git a/include/xcwm/window.h b/include/xcwm/window.h
index b476cb8..bd61944 100644
--- a/include/xcwm/window.h
+++ b/include/xcwm/window.h
@@ -253,4 +253,12 @@ xcwm_window_deiconify(xcwm_window_t *window);
 unsigned int
 xcwm_window_get_opacity(xcwm_window_t const *window);
 
+/**
+ * Get the shape of the window.
+ * @param window The window to get shape data for.
+ * @return The window shape, or 0 if unshaped
+ */
+xcb_rectangle_iterator_t
+xcwm_window_get_shape(xcwm_window_t const *window);
+
 #endif  /* _XCWM_WINDOW_H_ */
diff --git a/src/libxcwm/context.c b/src/libxcwm/context.c
index 88d2c32..4a80a25 100644
--- a/src/libxcwm/context.c
+++ b/src/libxcwm/context.c
@@ -101,6 +101,8 @@ xcwm_context_open(char *display)
 
     _xcwm_init_xfixes(root_context);
 
+    _xcwm_init_shape(root_context);
+
     /* Add the root window to our list of windows being managed */
     _xcwm_add_window(root_context->root_window);
 
diff --git a/src/libxcwm/event_loop.c b/src/libxcwm/event_loop.c
index fb480ab..4c1887f 100644
--- a/src/libxcwm/event_loop.c
+++ b/src/libxcwm/event_loop.c
@@ -195,7 +195,8 @@ run_event_loop(void *thread_arg_struct)
     xcb_flush(event_conn);
 
     while ((evt = xcb_wait_for_event(event_conn))) {
-        if ((evt->response_type & ~0x80) == context->damage_event_mask) {
+        uint8_t response_type = evt->response_type  & ~0x80;
+        if (response_type == context->damage_event_mask) {
             xcb_damage_notify_event_t *dmgevnt =
                 (xcb_damage_notify_event_t *)evt;
 
@@ -271,8 +272,21 @@ run_event_loop(void *thread_arg_struct)
             callback_ptr(&return_evt);
 
         }
+        else if (response_type == context->shape_event) {
+            xcb_shape_notify_event_t *shapeevnt =
+                (xcb_shape_notify_event_t *)evt;
+
+            if (shapeevnt->shape_kind == XCB_SHAPE_SK_BOUNDING) {
+                xcwm_window_t *window = _xcwm_get_window_node_by_window_id(shapeevnt->affected_window);
+                _xcwm_window_set_shape(window, shapeevnt->shaped);
+
+                return_evt.event_type = XCWM_EVENT_WINDOW_SHAPE;
+                return_evt.window = window;
+                callback_ptr(&return_evt);
+            }
+        }
         else {
-            switch (evt->response_type & ~0x80) {
+            switch (response_type) {
             case 0:
             {
                 /* Error case. Something very bad has happened. Spit
diff --git a/src/libxcwm/init.c b/src/libxcwm/init.c
index d5cd604..bc6a113 100644
--- a/src/libxcwm/init.c
+++ b/src/libxcwm/init.c
@@ -118,12 +118,34 @@ _xcwm_init_composite(xcwm_context_t *contxt)
 void
 _xcwm_init_xfixes(xcwm_context_t *contxt)
 {
+    xcb_query_extension_reply_t *reply =
+        _xcwm_init_extension(contxt->conn, "XFIXES");
+
     xcb_xfixes_query_version_cookie_t cookie =
         xcb_xfixes_query_version(contxt->conn, 4, 0);
 
-    xcb_xfixes_query_version_reply_t *reply =
+    xcb_xfixes_query_version_reply_t *version_reply =
         xcb_xfixes_query_version_reply(contxt->conn, cookie, NULL);
 
+    free(version_reply);
+    free(reply);
+}
+
+void
+_xcwm_init_shape(xcwm_context_t *contxt)
+{
+    xcb_query_extension_reply_t *reply =
+        _xcwm_init_extension(contxt->conn, "SHAPE");
+
+    xcb_shape_query_version_cookie_t cookie =
+        xcb_shape_query_version(contxt->conn);
+
+    xcb_shape_query_version_reply_t *version_reply =
+        xcb_shape_query_version_reply(contxt->conn, cookie, NULL);
+
+    contxt->shape_event = reply->first_event + XCB_SHAPE_NOTIFY;
+
+    free(version_reply);
     free(reply);
 }
 
diff --git a/src/libxcwm/window.c b/src/libxcwm/window.c
index 58e3ca4..d923330 100644
--- a/src/libxcwm/window.c
+++ b/src/libxcwm/window.c
@@ -47,6 +47,10 @@ set_wm_size_hints_for_window(xcb_connection_t *conn, xcwm_window_t *window);
 void
 init_damage_on_window(xcb_connection_t *conn, xcwm_window_t *window);
 
+/* Initialize reshape on a window */
+static void
+init_shape_on_window(xcb_connection_t *conn, xcwm_window_t *window);
+
 /* Set window to the top of the stack */
 void
 xcwm_window_set_to_top(xcwm_window_t *window)
@@ -116,6 +120,7 @@ _xcwm_window_create(xcwm_context_t *context, xcb_window_t new_window,
     window->opacity = ~0;
     window->composite_pixmap_id = 0;
     window->local_data = 0;
+    window->shape = 0;
 
     /* Find and set the parent */
     window->parent = _xcwm_get_window_node_by_window_id(parent);
@@ -142,6 +147,10 @@ _xcwm_window_create(xcwm_context_t *context, xcb_window_t new_window,
     /* register for damage */
     init_damage_on_window(context->conn, window);
 
+    /* note the shape, and register for re-shape */
+    _xcwm_window_set_shape(window, 1);
+    init_shape_on_window(context->conn, window);
+
     /* add window to window list for this context */
     window = _xcwm_add_window(window);
 
@@ -269,6 +278,9 @@ _xcwm_window_release(xcwm_window_t *window)
         return;
     }
 
+    if (window->shape)
+        free(window->shape);
+
     if (window->name) {
         free(window->name);
     }
@@ -366,6 +378,16 @@ xcwm_window_get_sizing(xcwm_window_t const *window)
     return &window->size_hints;
 }
 
+xcb_rectangle_iterator_t
+xcwm_window_get_shape(xcwm_window_t const *window)
+{
+    if (window->shape)
+        return xcb_shape_get_rectangles_rectangles_iterator(window->shape);
+
+    xcb_rectangle_iterator_t empty_iterator = {0,0,0};
+    return empty_iterator;
+}
+
 void
 xcwm_window_constrain_sizing(xcwm_window_t const *window, int *widthp, int *heightp)
 {
@@ -576,3 +598,49 @@ init_damage_on_window(xcb_connection_t *conn, xcwm_window_t *window)
     window->dmg_bounds.width = 0;
     window->dmg_bounds.height = 0;
 }
+
+void
+init_shape_on_window(xcb_connection_t *conn, xcwm_window_t *window)
+{
+    xcb_void_cookie_t cookie = xcb_shape_select_input(conn, window->window_id, 1 /* ShapeNotify */);
+
+    _xcwm_request_check(conn, cookie,
+                        "Could not select shape events on window");
+}
+
+void
+_xcwm_window_set_shape(xcwm_window_t *window, uint8_t shaped)
+{
+    if (window->shape)
+        free(window->shape);
+
+    /* If shaped == FALSE, window is unshaped and we don't need to ask to find shaped region */
+    if (shaped)
+    {
+        xcb_shape_get_rectangles_cookie_t cookie = xcb_shape_get_rectangles(window->context->conn,
+                                                                            window->window_id,
+                                                                            XCB_SHAPE_SK_BOUNDING);
+
+        xcb_shape_get_rectangles_reply_t *reply = xcb_shape_get_rectangles_reply(window->context->conn,
+                                                                                cookie,
+                                                                                NULL);
+
+        /* ... but unfortunately, there is no way to ask if a window is shaped initially, so
+           we have to check if we got exactly 1 rectangle which is the same as the window bounds
+           and treat that as unshaped, as well */
+        xcb_rectangle_iterator_t ri = xcb_shape_get_rectangles_rectangles_iterator(reply);
+        if ((ri.rem == 0) ||
+            ((ri.rem == 1) && (ri.data->x <= 0) && (ri.data->y <= 0)
+             && (ri.data->width >= window->bounds.width) && (ri.data->height >= window->bounds.height))) {
+            printf("window 0x%08x is actually unshaped\n", window->window_id);
+            window->shape = 0;
+            free(reply);
+        } else
+        {
+            window->shape = reply;
+        }
+    } else
+    {
+        window->shape = 0;
+    }
+}
diff --git a/src/libxcwm/xcwm_internal.h b/src/libxcwm/xcwm_internal.h
index cc183f8..3f9ca82 100644
--- a/src/libxcwm/xcwm_internal.h
+++ b/src/libxcwm/xcwm_internal.h
@@ -66,6 +66,7 @@ struct xcwm_context_t {
     int conn_screen;
     xcwm_window_t *root_window;
     int damage_event_mask;
+    int shape_event;
     xcb_window_t wm_cm_window;
     xcwm_wm_atoms_t atoms;
 };
@@ -90,6 +91,7 @@ struct xcwm_window_t {
     void *local_data;   /* Area for data client cares about */
     unsigned int opacity;
     xcb_pixmap_t composite_pixmap_id;
+    xcb_shape_get_rectangles_reply_t *shape;
 };
 
 /**
@@ -187,6 +189,13 @@ _xcwm_init_composite(xcwm_context_t *contxt);
 void
 _xcwm_init_xfixes(xcwm_context_t *contxt);
 
+/**
+ * Initialize the shape extension.
+ * @param contxt The context
+ */
+void
+_xcwm_init_shape(xcwm_context_t *contxt);
+
 /****************
 * event_loop.c
 ****************/
@@ -289,6 +298,13 @@ void
 _xcwm_resize_window(xcb_connection_t *conn, xcb_window_t window,
                     int x, int y, int width, int height);
 
+/**
+ * Update the window shape
+ * @param window The id of window to resize
+ * @param shaped TRUE if the window is shaped
+ */
+void
+_xcwm_window_set_shape(xcwm_window_t *window, uint8_t shaped);
 
 /****************
  * atoms.c