update invalidate area core window API

slightly extends the invalidate core window API with error return and
whole window invalidation. Also renames it to be more inline with
browser window API call.

cannot quite reuse browser window API yet as that applies scaling

Docs/core-window-interface

@@ -34,8 +34,8 @@ The header that defines the callback interface is netsurf/core_window.h
 The callback table contains five function pointer interfaces which the
 frontend must implement for the core.
 
- - redraw_request
-      request a redraw an area of a window
+ - invalidate
+      invalidate an area of a window
 
  - update_size
       Update the limits of the window 
@@ -67,27 +67,29 @@ core to provide the necessary interactions with the frontend windowing
 system.
 
 These actions should ideally use the standard frontend window
-processing. So for the GTK frontend when the core calls the redraw
+processing. So for the GTK frontend when the core calls the invalidate
 operation it simply marks the area passed as damaged (using
 gtk_widget_queue_draw_area()) and lets the standard expose event cause
-the redraw to occour.
+the redraw to occur.
 
 If the frontend needs to redraw an area of a window (perhaps an expose
-event occoured) it must call the corewindoe API wrappers
-implementation e.g in the case of ssl certificate viewer
+event occurred or the window has had an area marked as invalid) it
+must call the core window API wrappers implementation which will
+perform the plot operations required to update an area of the window.
+
+e.g in the case of ssl certificate viewer
 
 void sslcert_viewer_redraw(struct sslcert_session_data *ssl_d,
                            int x, int y, struct rect *clip,
                            const struct redraw_context *ctx);
 
-which will perform the plot operations required to update an area of
-the window for that SSL data.
+would perform the plot operations for that SSL data window.
 
 Usage
 -----
 
 The usage pattern that is expected is for a frontend to create a core
-window impementation that implements the necessary five API in a
+window implementation that implements the necessary five API in a
 generic way and allows the frontend to provide the specific
 specialisation for each of the user interface elements it wishes to
 use (cookies, SSL viewer etc).
@@ -95,7 +97,7 @@ use (cookies, SSL viewer etc).
 The GTK frontend for example:
 
 has source corewindow.[ch] which implement the five core callbacks
-using generic GTK operations (redraw_request calls
+using generic GTK operations (invalidate calls
 gtk_widget_queue_draw_area() etc.) and then provides additional
 operations on a GTK drawing area object to attach expose event
 processing, keypress processing etc.
@@ -110,7 +112,7 @@ calls sslcert_viewer_init() directly.
 frontend skeleton
 -----------------
 
-An example core window implementation for a frontend ssl certficiate
+An example core window implementation for a frontend ssl certificate
 viewer is presented here. This implements the suggested usage above
 and provides generic corewindow helpers.
 
@@ -313,8 +315,8 @@ example_cw_draw_event(toolkit_widget *widget,
 /**
  * callback from core to request a redraw
  */
-static void
-example_cw_redraw_request(struct core_window *cw, const struct rect *r)
+static nserror
+example_cw_invalidate(struct core_window *cw, const struct rect *r)
 {
         struct example_corewindow *example_cw = (struct example_corewindow *)cw;
 
@@ -362,7 +364,7 @@ example_cw_drag_status(struct core_window *cw, core_window_drag_status ds)
 
 
 struct core_window_callback_table example_cw_cb_table = {
-        .redraw_request = example_cw_redraw_request,
+        .invalidate = example_cw_invalidate,
         .update_size = example_cw_update_size,
         .scroll_visible = example_cw_scroll_visible,
         .get_window_dimensions = example_cw_get_window_dimensions,

desktop/local_history.c

@@ -23,6 +23,7 @@
 
 #include <stdlib.h>
 
+#include "utils/errors.h"
 #include "netsurf/types.h"
 #include "netsurf/core_window.h"
 

desktop/treeview.c

@@ -315,12 +315,12 @@ static struct treeview_resource treeview_res[TREE_RES_LAST] = {
  * \param[in] tree The treeview to request redraw on.
  * \param[in] r rectangle to redraw
  */
-static inline void treeview__cw_redraw_request(
-	const struct treeview *tree,
+static inline
+void cw_invalidate_area(const struct treeview *tree,
 			const struct rect *r)
 {
 	if (tree->cw_t != NULL) {
-		tree->cw_t->redraw_request(tree->cw_h, r);
+		tree->cw_t->invalidate(tree->cw_h, r);
 	}
 }
 
@@ -791,7 +791,7 @@ treeview_create_node_folder(treeview *tree,
 			r.y0 = treeview_node_y(tree, n);
 			r.x1 = REDRAW_MAX;
 			r.y1 = tree->root->height;
-			treeview__cw_redraw_request(tree, &r);
+			cw_invalidate_area(tree, &r);
 		}
 	}
 
@@ -842,7 +842,7 @@ treeview_update_node_folder(treeview *tree,
 		r.y0 = treeview_node_y(tree, folder);
 		r.x1 = REDRAW_MAX;
 		r.y1 = r.y0 + tree_g.line_height;
-		treeview__cw_redraw_request(tree, &r);
+		cw_invalidate_area(tree, &r);
 	}
 
 	return NSERROR_OK;
@@ -914,7 +914,7 @@ treeview_update_node_entry(treeview *tree,
 		r.y0 = treeview_node_y(tree, entry);
 		r.x1 = REDRAW_MAX;
 		r.y1 = r.y0 + entry->height;
-		treeview__cw_redraw_request(tree, &r);
+		cw_invalidate_area(tree, &r);
 	}
 
 	return NSERROR_OK;
@@ -1001,7 +1001,7 @@ treeview_create_node_entry(treeview *tree,
 			r.y0 = treeview_node_y(tree, n);
 			r.x1 = REDRAW_MAX;
 			r.y1 = tree->root->height;
-			treeview__cw_redraw_request(tree, &r);
+			cw_invalidate_area(tree, &r);
 		}
 	}
 
@@ -1154,7 +1154,7 @@ static void treeview_edit_cancel(treeview *tree, bool redraw)
 		r.y0 = tree->edit.y;
 		r.x1 = tree->edit.x + tree->edit.w;
 		r.y1 = tree->edit.y + tree->edit.h;
-		treeview__cw_redraw_request(tree, &r);
+		cw_invalidate_area(tree, &r);
 	}
 }
 
@@ -1496,7 +1496,7 @@ treeview_delete_node(treeview *tree,
 	if (visible && !(flags & TREE_OPTION_SUPPRESS_REDRAW)) {
 		r.x0 = 0;
 		r.x1 = REDRAW_MAX;
-		treeview__cw_redraw_request(tree, &r);
+		cw_invalidate_area(tree, &r);
 	}
 
 	return NSERROR_OK;
@@ -1755,7 +1755,7 @@ nserror treeview_node_expand(treeview *tree, treeview_node *node)
 		r.x1 = REDRAW_MAX;
 		r.y1 = tree->root->height;
 
-		treeview__cw_redraw_request(tree, &r);
+		cw_invalidate_area(tree, &r);
 	}
 
 	return res;
@@ -1864,7 +1864,7 @@ nserror treeview_node_contract(treeview *tree, treeview_node *node)
 		r.x1 = REDRAW_MAX;
 		r.y1 = tree->root->height;
 
-		treeview__cw_redraw_request(tree, &r);
+		cw_invalidate_area(tree, &r);
 	}
 
 	return res;
@@ -1911,7 +1911,7 @@ nserror treeview_contract(treeview *tree, bool all)
 	treeview__cw_update_size(tree, -1, tree->root->height);
 
 	/* Redraw */
-	treeview__cw_redraw_request(tree, &r);
+	cw_invalidate_area(tree, &r);
 
 	return NSERROR_OK;
 }
@@ -1985,7 +1985,7 @@ nserror treeview_expand(treeview *tree, bool only_folders)
 		r.x1 = REDRAW_MAX;
 		r.y1 = tree->root->height;
 
-		treeview__cw_redraw_request(tree, &r);
+		cw_invalidate_area(tree, &r);
 	}
 	return res;
 }
@@ -3182,7 +3182,7 @@ bool treeview_keypress(treeview *tree, uint32_t key)
 	}
 
 	if (redraw) {
-		treeview__cw_redraw_request(tree, &r);
+		cw_invalidate_area(tree, &r);
 	}
 
 	return true;
@@ -3358,7 +3358,7 @@ static void treeview_textarea_callback(void *data, struct textarea_msg *msg)
 		r->y1 += tree->edit.y;
 
 		/* Redraw the textarea */
-		treeview__cw_redraw_request(tree, r);
+		cw_invalidate_area(tree, r);
 		break;
 
 	default:
@@ -3536,7 +3536,7 @@ void treeview_edit_selection(treeview *tree)
 	rect.y0 = y;
 	rect.x1 = REDRAW_MAX;
 	rect.y1 = y + tree_g.line_height;
-	treeview__cw_redraw_request(tree, &rect);
+	cw_invalidate_area(tree, &rect);
 }
 
 
@@ -3816,7 +3816,7 @@ treeview_node_mouse_action_cb(treeview_node *node,
 	}
 
 	if (redraw) {
-		treeview__cw_redraw_request(ma->tree, &r);
+		cw_invalidate_area(ma->tree, &r);
 	}
 
 	*end = true; /* Reached line with click; stop walking tree */
@@ -3878,7 +3878,7 @@ treeview_mouse_action(treeview *tree, browser_mouse_state mouse, int x, int y)
 			tree->move.target_pos = TV_TARGET_NONE;
 
 			treeview__cw_drag_status(tree, CORE_WINDOW_DRAG_NONE);
-			treeview__cw_redraw_request(tree, &r);
+			cw_invalidate_area(tree, &r);
 			return;
 		default:
 			/* No drag to end */
@@ -3953,7 +3953,7 @@ treeview_mouse_action(treeview *tree, browser_mouse_state mouse, int x, int y)
 		}
 
 		if (redraw) {
-			treeview__cw_redraw_request(tree, &r);
+			cw_invalidate_area(tree, &r);
 		}
 
 	} else {

include/netsurf/core_window.h

@@ -20,7 +20,7 @@
  * \file
  * Interface to core window handling.
  *
- * This provides a generallised API for frontends to implement which
+ * This provides a generalised API for frontends to implement which
  *  allows them to provide a single implementation for general window
  *  operations on their platform.
  *
@@ -35,6 +35,9 @@
 struct core_window;
 struct rect;
 
+/**
+ * drag status passed to drag_status callback
+ */
 typedef enum {
 	CORE_WINDOW_DRAG_NONE,
 	CORE_WINDOW_DRAG_SELECTION,
@@ -42,15 +45,28 @@ typedef enum {
 	CORE_WINDOW_DRAG_MOVE
 } core_window_drag_status;
 
-/** Callbacks to achieve various core window functionality. */
+/**
+ * Callbacks to achieve various core window functionality.
+ */
 struct core_window_callback_table {
 	/**
-	 * Request a redraw of the window
+	 * Invalidate an area of a window.
 	 *
-	 * \param[in] cw the core window object
-	 * \param[in] r rectangle to redraw
+	 * The specified area of the window should now be considered
+	 *  out of date. If the area is NULL the entire window must be
+	 *  invalidated. It is expected that the windowing system will
+	 *  then subsequently cause redraw/expose operations as
+	 *  necessary.
+	 *
+	 * \note the frontend should not attempt to actually start the
+	 *  redraw operations as a result of this callback because the
+	 *  core redraw functions may already be threaded.
+	 *
+	 * \param[in] cw The core window to invalidate.
+	 * \param[in] rect area to redraw or NULL for the entire window area
+	 * \return NSERROR_OK on success or appropriate error code
 	 */
-	void (*redraw_request)(struct core_window *cw, const struct rect *r);
+	nserror (*invalidate)(struct core_window *cw, const struct rect *rect);
 
 	/**
 	 * Update the limits of the window