Merge branch 'surface-errors' of https://github.com/psychon/awesome

draw.c

@@ -229,23 +229,18 @@ draw_dup_image_surface(cairo_surface_t *surface)
 /** Load the specified path into a cairo surface
  * \param L Lua state
  * \param path file to load
+ * \param error A place to store an error message, if needed
  * \return A cairo image surface or NULL on error.
  */
 cairo_surface_t *
-draw_load_image(lua_State *L, const char *path)
+draw_load_image(lua_State *L, const char *path, GError **error)
 {
-    GError *error = NULL;
     cairo_surface_t *ret;
-    GdkPixbuf *buf = gdk_pixbuf_new_from_file(path, &error);
+    GdkPixbuf *buf = gdk_pixbuf_new_from_file(path, error);
 
-    if (!buf) {
+    if (!buf)
-        luaL_where(L, 1);
+        /* error was set above */
-        lua_pushstring(L, error->message);
-        lua_concat(L, 2);
-        g_error_free(error);
-        lua_error(L);
         return NULL;
-    }
 
     ret = draw_surface_from_pixbuf(buf);
     g_object_unref(buf);

draw.h

@@ -25,6 +25,7 @@
 #include <xcb/xcb.h>
 #include <cairo.h>
 #include <lua.h>
+#include <glib.h> /* for GError */
 
 #include "common/util.h"
 
@@ -70,7 +71,7 @@ a_iso2utf8(const char *str, ssize_t len, char **dest, ssize_t *dlen)
 
 cairo_surface_t *draw_surface_from_data(int width, int height, uint32_t *data);
 cairo_surface_t *draw_dup_image_surface(cairo_surface_t *surface);
-cairo_surface_t *draw_load_image(lua_State *L, const char *path);
+cairo_surface_t *draw_load_image(lua_State *L, const char *path, GError **error);
 
 xcb_visualtype_t *draw_find_visual(const xcb_screen_t *s, xcb_visualid_t visual);
 xcb_visualtype_t *draw_default_visual(const xcb_screen_t *s);

lib/awful/menu.lua

@@ -558,7 +558,7 @@ function menu.entry(parent, args)
     if type(args.cmd) == "table" then
         if args.theme.submenu_icon then
             submenu = wibox.widget.imagebox()
-            submenu:set_image(surface.load(args.theme.submenu_icon))
+            submenu:set_image(args.theme.submenu_icon)
         else
             submenu = wibox.widget.textbox()
             submenu:set_font(args.theme.font)

lib/awful/widget/taglist.lua

@@ -107,9 +107,7 @@ function taglist.taglist_label(t, args)
         text = text .. "</span>"
     end
     if not taglist_disable_icon then
-        if tag.geticon(t) and type(tag.geticon(t)) == "image" then
+        if tag.geticon(t) then
-            icon = tag.geticon(t)
-        elseif tag.geticon(t) then
             icon = surface.load(tag.geticon(t))
         end
     end

lib/gears/surface.lua

@@ -9,6 +9,7 @@ local setmetatable = setmetatable
 local type = type
 local capi = { awesome = awesome }
 local cairo = require("lgi").cairo
+local gdebug = require("gears.debug")
 
 -- Keep this in sync with build-utils/lgi-check.sh!
 local ver_major, ver_minor, ver_patch = string.match(require('lgi.version'), '(%d)%.(%d)%.(%d)')
@@ -19,13 +20,22 @@ end
 local surface = { mt = {} }
 local surface_cache = setmetatable({}, { __mode = 'v' })
 
+local function get_empty_surface()
+    return cairo.ImageSurface(cairo.Format.ARGB32, 0, 0)
+end
+
 --- Try to convert the argument into an lgi cairo surface.
 -- This is usually needed for loading images by file name.
-function surface.load_uncached(_surface)
+-- @param _surface The surface to load or nil
+-- @param default The default value to return on error; when nil, then a surface
+-- in an error state is returned.
+-- @return The loaded surface, or the replacement default
+-- @return An error message, or nil on success
+function surface.load_uncached_silently(_surface, default)
     local file
-    -- Nil is not changed
+    -- On nil, return an empty surface
     if not _surface then
-        return nil
+        return get_empty_surface()
     end
     -- Remove from cache if it was cached
     surface_cache[_surface] = nil
@@ -35,8 +45,15 @@ function surface.load_uncached(_surface)
     end
     -- Strings are assumed to be file names and get loaded
     if type(_surface) == "string" then
+        local err
         file = _surface
-        _surface = capi.awesome.load_image(file)
+        _surface, err = capi.awesome.load_image(file)
+        if not _surface then
+            if type(default) == 'nil' then
+                default = get_empty_surface()
+            end
+            return default, err
+        end
     end
     -- Everything else gets forced into a surface
     _surface = cairo.Surface(_surface, true)
@@ -47,14 +64,53 @@ function surface.load_uncached(_surface)
     return _surface
 end
 
-function surface.load(_surface)
+--- Try to convert the argument into an lgi cairo surface.
+-- This is usually needed for loading images by file name and uses a cache.
+-- In contrast to `load()`, errors are returned to the caller.
+-- @param _surface The surface to load or nil
+-- @param default The default value to return on error; when nil, then a surface
+-- in an error state is returned.
+-- @return The loaded surface, or the replacement default, or nil if called with
+-- nil.
+-- @return An error message, or nil on success
+function surface.load_silently(_surface, default)
     if type(_surface) == "string" then
         local cache = surface_cache[_surface]
         if cache then
             return cache
         end
     end
-    return surface.load_uncached(_surface)
+    return surface.load_uncached_silently(_surface, default)
+end
+
+local function do_load_and_handle_errors(_surface, func)
+    if type(_surface) == 'nil' then
+        return get_empty_surface()
+    end
+    local result, err = func(_surface, false)
+    if result then
+        return result
+    end
+    gdebug.print_error("Failed to load '" .. tostring(_surface) .. "': " .. tostring(err))
+    return get_empty_surface()
+end
+
+--- Try to convert the argument into an lgi cairo surface.
+-- This is usually needed for loading images by file name. Errors are handled
+-- via `gears.debug.print_error`.
+-- @param _surface The surface to load or nil
+-- @return The loaded surface, or nil
+function surface.load_uncached(_surface)
+    return do_load_and_handle_errors(_surface, surface.load_uncached_silently)
+end
+
+--- Try to convert the argument into an lgi cairo surface.
+-- This is usually needed for loading images by file name. Errors are handled
+-- via `gears.debug.print_error`.
+-- @param _surface The surface to load or nil
+-- @return The loaded surface, or nil
+function surface.load(_surface)
+    return do_load_and_handle_errors(_surface, surface.load_silently)
 end
 
 function surface.mt:__call(...)
@@ -70,7 +126,6 @@ function surface.get_size(surf)
     return w - x, h - y
 end
 
-
 --- Create a copy of a cairo surface.
 -- The surfaces returned by `surface.load` are cached and must not be
 -- modified to avoid unintended side-effects. This function allows to create

lib/naughty/core.lua

@@ -562,13 +562,7 @@ function naughty.notify(args)
         end
 
         -- is the icon file readable?
-        local success, res = pcall(function() return surface.load_uncached(icon) end)
+        local icon = surface.load_uncached(icon)
-        if success then
-            icon = res
-        else
-            io.stderr:write(string.format("naughty: Couldn't load image '%s': %s\n", tostring(icon), res))
-            icon = nil
-        end
 
         -- if we have an icon, use it
         if icon then

lib/wibox/widget/imagebox.lua

@@ -72,17 +72,16 @@ end
 --- Set an imagebox' image
 -- @param image Either a string or a cairo image surface. A string is
 --   interpreted as the path to a png image file.
+-- @return true on success, false if the image cannot be used
 function imagebox:set_image(image)
     local image = image
 
     if type(image) == "string" then
-        local success, result = pcall(surface.load, image)
+        image = surface.load(image)
-        if not success then
+        if not image then
-            print("Error while reading '" .. image .. "': " .. result)
             print(debug.traceback())
             return false
         end
-        image = result
     end
 
     image = surface.load(image)

luaa.c

@@ -147,16 +147,24 @@ luaA_restart(lua_State *L)
 /** Load an image from a given path.
  *
  * @param name The file name.
- * @return A cairo surface as light user datum.
+ * @return[1] A cairo surface as light user datum.
+ * @return[2] nil
+ * @treturn[2] string Error message
  * @function load_image
  */
 static int
 luaA_load_image(lua_State *L)
 {
+    GError *error = NULL;
     const char *filename = luaL_checkstring(L, 1);
-    cairo_surface_t *surface = draw_load_image(L, filename);
+    cairo_surface_t *surface = draw_load_image(L, filename, &error);
-    if (!surface)
+    if (!surface) {
-        return 0;
+        lua_pushnil(L);
+        lua_pushstring(L, error->message);
+        g_error_free(error);
+        return 2;
+    }
+
     /* lua has to make sure to free the ref or we have a leak */
     lua_pushlightuserdata(L, surface);
     return 1;

objects/drawable.c

@@ -124,8 +124,11 @@ drawable_set_geometry(lua_State *L, int didx, area_t geom)
 static int
 luaA_drawable_get_surface(lua_State *L, drawable_t *drawable)
 {
-    /* Lua gets its own reference which it will have to destroy */
+    if (drawable->surface)
-    lua_pushlightuserdata(L, cairo_surface_reference(drawable->surface));
+        /* Lua gets its own reference which it will have to destroy */
+        lua_pushlightuserdata(L, cairo_surface_reference(drawable->surface));
+    else
+        lua_pushnil(L);
     return 1;
 }