Implement some more on borders

Note that this segfaults ALL THE TIME in wlc code. Paging @Cloudef for
help, I'm at a loss.

include/container.h

@@ -36,6 +36,12 @@ enum swayc_layouts {
 	L_LAYOUTS,
 };
 
+enum swayc_border_types {
+    B_NONE,             /**< No border */
+    B_PIXEL,            /**< 1px border */
+    B_NORMAL            /**< Normal border with title bar */
+};
+
 /**
  * Stores information about a container.
  *
@@ -109,6 +115,15 @@ struct sway_container {
 	 * If this container's children include a fullscreen view, this is that view.
 	 */
 	struct sway_container *fullscreen;
+    /**
+     * If this container is a view, this may be set to the window's decoration
+     * buffer (or NULL).
+     */
+    unsigned char *border;
+    enum swayc_border_types border_type;
+	struct wlc_geometry border_geometry;
+	struct wlc_geometry presumed_geometry;
+    int border_thickness;
 };
 
 enum visibility_mask {

include/render.h

@@ -1,7 +1,9 @@
 #ifndef _SWAY_RENDER_H
 #define _SWAY_RENDER_H
 #include <wlc/wlc.h>
+#include "container.h"
 
 void render_view_borders(wlc_handle view);
+void update_view_border(swayc_t *view);
 
 #endif

sway/container.c

@@ -22,8 +22,11 @@ static swayc_t *new_swayc(enum swayc_types type) {
 	c->gaps = -1;
 	c->layout = L_NONE;
 	c->type = type;
+	c->border_type = B_PIXEL; // TODO: Load default from config
+	c->border_thickness = 2;
 	if (type != C_VIEW) {
 		c->children = create_list();
+		c->border_type = B_NONE;
 	}
 	return c;
 }

sway/handlers.c

@@ -357,6 +357,7 @@ static void handle_view_geometry_request(wlc_handle handle, const struct wlc_geo
 			arrange_windows(view->parent, -1, -1);
 		}
 	}
+	update_view_border(view);
 }
 
 static void handle_view_state_request(wlc_handle view, enum wlc_view_state_bit state, bool toggle) {

sway/layout.c

@@ -12,6 +12,7 @@
 #include "focus.h"
 #include "output.h"
 #include "ipc-server.h"
+#include "render.h"
 
 swayc_t root_container;
 list_t *scratchpad;

sway/render.c

@@ -2,6 +2,8 @@
 #include <wlc/wlc-render.h>
 #include <cairo/cairo.h>
 #include <stdlib.h>
+#include <stdio.h>
+#include "container.h"
 
 void cairo_set_source_u32(cairo_t *cairo, uint32_t color) {
 	cairo_set_source_rgba(cairo,
@@ -11,40 +13,101 @@ void cairo_set_source_u32(cairo_t *cairo, uint32_t color) {
 			(color >> (0*8) & 0xFF) / 255.0);
 }
 
-cairo_t *create_cairo_context(int width, int height, int channels,
-		cairo_surface_t **surf, unsigned char **buf) {
+cairo_t *create_border_buffer(swayc_t *view, struct wlc_geometry geo,
+		cairo_surface_t **surface) {
+	const int channels = 4;
 	cairo_t *cr;
-	*buf = calloc(channels * width * height, sizeof(unsigned char));
-	if (!*buf) {
+	view->border_geometry = geo;
+	view->border = calloc(channels * geo.size.w * geo.size.h,
+			sizeof(unsigned char));
+	if (!view->border) {
+		sway_log(L_DEBUG, "Unable to allocate buffer");
 		return NULL;
 	}
-	*surf = cairo_image_surface_create_for_data(*buf, CAIRO_FORMAT_ARGB32,
-		width, height, channels * width);
-	if (cairo_surface_status(*surf) != CAIRO_STATUS_SUCCESS) {
-		free(*buf);
+	*surface = cairo_image_surface_create_for_data(view->border,
+			CAIRO_FORMAT_ARGB32, geo.size.w, geo.size.h, channels * geo.size.w);
+	if (cairo_surface_status(*surface) != CAIRO_STATUS_SUCCESS) {
+		free(view->border);
+		view->border = NULL;
+		sway_log(L_DEBUG, "Unable to allocate surface");
 		return NULL;
 	}
-	cr = cairo_create(*surf);
+	cr = cairo_create(*surface);
 	if (cairo_status(cr) != CAIRO_STATUS_SUCCESS) {
-		free(*buf);
+		cairo_surface_destroy(*surface);
+		free(view->border);
+		view->border = NULL;
+		sway_log(L_DEBUG, "Unable to create cairo context");
 		return NULL;
 	}
 	return cr;
 }
 
-void render_view_borders(wlc_handle view) {
-	const int bw = 2;
-	unsigned char *surf_data;
-	cairo_surface_t *surf;
-	struct wlc_geometry geo = *wlc_view_get_geometry(view);
-	cairo_t *cr = create_cairo_context(geo.size.w + bw * 2, geo.size.h + bw * 2, 4, &surf, &surf_data);
-	cairo_set_source_u32(cr, 0x0000FFFF);
-	cairo_paint(cr);
-	geo.origin.x -= bw;
-	geo.origin.y -= bw;
-	geo.size.w += bw * 2;
-	geo.size.h += bw * 2;
-	wlc_pixels_write(WLC_RGBA8888, &geo, surf_data);
-	cairo_destroy(cr);
-	free(surf_data);
+void update_view_border(swayc_t *view) {
+	struct wlc_geometry geo;
+	wlc_view_get_visible_geometry(view->handle, &geo);
+	cairo_t *cr = NULL;
+	cairo_surface_t *surface = NULL;
+
+	if (view->border) {
+		free(view->border);
+		view->border = NULL;
+	}
+
+	switch (view->border_type) {
+	case B_NONE:
+		view->border_geometry = geo;
+		break;
+	case B_PIXEL:
+		geo.origin.x -= view->border_thickness;
+		geo.origin.y -= view->border_thickness;
+		geo.size.w += view->border_thickness * 2;
+		geo.size.h += view->border_thickness * 2;
+		if (geo.size.w <= 0 || geo.size.h <= 0) {
+			view->border = NULL;
+			break;
+		}
+		cr = create_border_buffer(view, geo, &surface);
+		if (!cr) {
+			break;
+		}
+		cairo_set_source_u32(cr, 0x0000FFFF);
+		cairo_paint(cr);
+		break;
+	case B_NORMAL:
+		// TODO
+		break;
+	}
+	if (surface) {
+		cairo_surface_flush(surface);
+		cairo_surface_destroy(surface);
+	}
+	if (cr) {
+		cairo_destroy(cr);
+		sway_log(L_DEBUG, "Created border for %p (%dx%d+%d,%d)", view,
+				geo.size.w, geo.size.h, geo.origin.x, geo.origin.y);
+	}
+	view->border_geometry = geo;
+}
+
+void render_view_borders(wlc_handle view) {
+	swayc_t *c = swayc_by_handle(view);
+	if (!c || c->border_type == B_NONE) {
+		return;
+	}
+	struct wlc_geometry geo;
+	wlc_view_get_visible_geometry(view, &geo);
+	if (geo.size.w != c->presumed_geometry.size.w
+			|| geo.size.h != c->presumed_geometry.size.h
+			|| geo.origin.x != c->presumed_geometry.origin.x
+			|| geo.origin.y != c->presumed_geometry.origin.y) {
+		update_view_border(c);
+		c->presumed_geometry = geo;
+	}
+	if (c->border) {
+		geo = c->border_geometry;
+		sway_log(L_DEBUG, "Rendering border for %p (%dx%d+%d,%d)", c,
+				geo.size.w, geo.size.h, geo.origin.x, geo.origin.y);
+		wlc_pixels_write(WLC_RGBA8888, &c->border_geometry, c->border);
+	}
 }