gtk2/gtk/gtkicontheme.c

/* GtkIconTheme - a loader for icon themes
 * gtk-icon-theme.c Copyright (C) 2002, 2003 Red Hat, Inc.
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library. If not, see <http://www.gnu.org/licenses/>.
 */

#include "config.h"

#include <sys/types.h>
#include <sys/stat.h>
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif
#include <string.h>
#include <stdlib.h>
#include <math.h>
#include <glib.h>
#include <glib/gstdio.h>

#ifdef G_OS_WIN32
#ifndef S_ISDIR
#define S_ISDIR(mode) ((mode)&_S_IFDIR)
#endif
#define WIN32_MEAN_AND_LEAN
#include <windows.h>
#include "win32/gdkwin32.h"
#endif /* G_OS_WIN32 */

#include "gtkiconthemeprivate.h"
#include "gtkcsspalettevalueprivate.h"
#include "gtkcssrgbavalueprivate.h"
#include "gtkdebug.h"
#include "gtkiconcache.h"
#include "gtkintl.h"
#include "gtkmain.h"
#include "gtksettingsprivate.h"
#include "gtkstylecontextprivate.h"
#include "gtkprivate.h"
#include "gdkpixbufutilsprivate.h"

/* this is in case round() is not provided by the compiler, 
 * such as in the case of C89 compilers, like MSVC
 */
#include "fallback-c89.c"

/**
 * SECTION:gtkicontheme
 * @Short_description: Looking up icons by name
 * @Title: GtkIconTheme
 *
 * #GtkIconTheme provides a facility for looking up icons by name
 * and size. The main reason for using a name rather than simply
 * providing a filename is to allow different icons to be used
 * depending on what “icon theme” is selected
 * by the user. The operation of icon themes on Linux and Unix
 * follows the [Icon Theme Specification](http://www.freedesktop.org/Standards/icon-theme-spec)
 * There is a fallback icon theme, named `hicolor`, where applications
 * should install their icons, but additional icon themes can be installed
 * as operating system vendors and users choose.
 *
 * In many cases, named themes are used indirectly, via #GtkImage
 * rather than directly, but looking up icons
 * directly is also simple. The #GtkIconTheme object acts
 * as a database of all the icons in the current theme. You
 * can create new #GtkIconTheme objects, but it’s much more
 * efficient to use the standard icon theme for the #GdkScreen
 * so that the icon information is shared with other people
 * looking up icons.
 * |[<!-- language="C" -->
 * GError *error = NULL;
 * GtkIconTheme *icon_theme;
 * GdkPixbuf *pixbuf;
 *
 * icon_theme = gtk_icon_theme_get_default ();
 * pixbuf = gtk_icon_theme_load_icon (icon_theme,
 *                                    "my-icon-name", // icon name
 *                                    48, // icon size
 *                                    0,  // flags
 *                                    &error);
 * if (!pixbuf)
 *   {
 *     g_warning ("Couldn’t load icon: %s", error->message);
 *     g_error_free (error);
 *   }
 * else
 *   {
 *     // Use the pixbuf
 *     g_object_unref (pixbuf);
 *   }
 * ]|
 */

#define FALLBACK_ICON_THEME "hicolor"

typedef enum
{
  ICON_THEME_DIR_FIXED,  
  ICON_THEME_DIR_SCALABLE,  
  ICON_THEME_DIR_THRESHOLD,
  ICON_THEME_DIR_UNTHEMED
} IconThemeDirType;

/* In reverse search order: */
typedef enum
{
  ICON_SUFFIX_NONE = 0,
  ICON_SUFFIX_XPM = 1 << 0,
  ICON_SUFFIX_SVG = 1 << 1,
  ICON_SUFFIX_PNG = 1 << 2,
  HAS_ICON_FILE = 1 << 3,
  ICON_SUFFIX_SYMBOLIC_PNG = 1 << 4
} IconSuffix;

#define INFO_CACHE_LRU_SIZE 32
#if 0
#define DEBUG_CACHE(args) g_print args
#else
#define DEBUG_CACHE(args)
#endif

struct _GtkIconThemePrivate
{
  GHashTable *info_cache;
  GList *info_cache_lru;

  gchar *current_theme;
  gchar **search_path;
  gint search_path_len;
  GList *resource_paths;

  guint custom_theme        : 1;
  guint is_screen_singleton : 1;
  guint pixbuf_supports_svg : 1;
  guint themes_valid        : 1;
  guint loading_themes      : 1;

  /* A list of all the themes needed to look up icons.
   * In search order, without duplicates
   */
  GList *themes;
  GHashTable *unthemed_icons;

  /* GdkScreen for the icon theme (may be NULL) */
  GdkScreen *screen;

  /* time when we last stat:ed for theme changes */
  glong last_stat_time;
  GList *dir_mtimes;

  gulong theme_changed_idle;
};

typedef struct {
  gchar **icon_names;
  gint size;
  gint scale;
  GtkIconLookupFlags flags;
} IconInfoKey;

typedef struct _SymbolicPixbufCache SymbolicPixbufCache;

struct _SymbolicPixbufCache {
  GdkPixbuf *pixbuf;
  GdkPixbuf *proxy_pixbuf;
  GdkRGBA  fg;
  GdkRGBA  success_color;
  GdkRGBA  warning_color;
  GdkRGBA  error_color;
  SymbolicPixbufCache *next;
};

struct _GtkIconInfoClass
{
  GObjectClass parent_class;
};

struct _GtkIconInfo
{
  GObject parent_instance;

  /* Information about the source
   */
  IconInfoKey key;
  GtkIconTheme *in_cache;

  gchar *filename;
  GFile *icon_file;
  GLoadableIcon *loadable;
  GSList *emblem_infos;

  /* Cache pixbuf (if there is any) */
  GdkPixbuf *cache_pixbuf;

  /* Information about the directory where
   * the source was found
   */
  IconThemeDirType dir_type;
  gint dir_size;
  gint dir_scale;
  gint min_size;
  gint max_size;

  /* Parameters influencing the scaled icon
   */
  gint desired_size;
  gint desired_scale;
  guint forced_size     : 1;
  guint emblems_applied : 1;
  guint is_svg          : 1;
  guint is_resource     : 1;

  /* Cached information if we go ahead and try to load
   * the icon.
   */
  GdkPixbuf *pixbuf;
  GdkPixbuf *proxy_pixbuf;
  GError *load_error;
  gdouble unscaled_scale;
  gdouble scale;

  SymbolicPixbufCache *symbolic_pixbuf_cache;

  gint symbolic_width;
  gint symbolic_height;
};

typedef struct
{
  gchar *name;
  gchar *display_name;
  gchar *comment;
  gchar *example;

  /* In search order */
  GList *dirs;
} IconTheme;

typedef struct
{
  IconThemeDirType type;
  GQuark context;

  gint size;
  gint min_size;
  gint max_size;
  gint threshold;
  gint scale;
  gboolean is_resource;

  gchar *dir;
  gchar *subdir;
  gint subdir_index;
  
  GtkIconCache *cache;
  
  GHashTable *icons;
} IconThemeDir;

typedef struct
{
  gchar *svg_filename;
  gchar *no_svg_filename;
  gboolean is_resource;
} UnthemedIcon;

typedef struct
{
  gint size;
  GdkPixbuf *pixbuf;
} BuiltinIcon;

typedef struct 
{
  gchar *dir;
  time_t mtime;
  GtkIconCache *cache;
  gboolean exists;
} IconThemeDirMtime;

static void         gtk_icon_theme_finalize   (GObject          *object);
static void         theme_dir_destroy         (IconThemeDir     *dir);
static void         theme_destroy              (IconTheme       *theme);
static GtkIconInfo *theme_lookup_icon         (IconTheme        *theme,
                                               const gchar      *icon_name,
                                               gint              size,
                                               gint              scale,
                                               gboolean          allow_svg,
                                               gboolean          use_default_icons);
static void         theme_list_icons          (IconTheme        *theme,
                                               GHashTable       *icons,
                                               GQuark            context);
static gboolean     theme_has_icon            (IconTheme        *theme,
                                               const gchar      *icon_name);
static void         theme_list_contexts       (IconTheme        *theme,
                                               GHashTable       *contexts);
static void         theme_subdir_load         (GtkIconTheme     *icon_theme,
                                               IconTheme        *theme,
                                               GKeyFile         *theme_file,
                                               gchar            *subdir);
static void         do_theme_change           (GtkIconTheme     *icon_theme);
static void         blow_themes               (GtkIconTheme     *icon_themes);
static gboolean     rescan_themes             (GtkIconTheme     *icon_themes);
static IconSuffix   theme_dir_get_icon_suffix (IconThemeDir     *dir,
                                               const gchar      *icon_name,
                                               gboolean         *has_icon_file);
static GtkIconInfo *icon_info_new             (IconThemeDirType  type,
                                               gint              dir_size,
                                               gint              dir_scale);
static GtkIconInfo *icon_info_new_builtin     (BuiltinIcon      *icon);
static IconSuffix   suffix_from_name          (const gchar      *name);
static BuiltinIcon *find_builtin_icon         (const gchar      *icon_name,
                                               gint              size,
                                               gint              scale,
                                               gint             *min_difference_p);
static void         remove_from_lru_cache     (GtkIconTheme     *icon_theme,
                                               GtkIconInfo      *icon_info);
static gboolean     icon_info_ensure_scale_and_pixbuf (GtkIconInfo* icon_info);

static guint signal_changed = 0;

static GHashTable *icon_theme_builtin_icons;

static guint
icon_info_key_hash (gconstpointer _key)
{
  const IconInfoKey *key = _key;
  guint h = 0;
  int i;
  for (i = 0; key->icon_names[i] != NULL; i++)
    h ^= g_str_hash (key->icon_names[i]);

  h ^= key->size * 0x10001;
  h ^= key->scale * 0x1000010;
  h ^= key->flags * 0x100000100;

  return h;
}

static gboolean
icon_info_key_equal (gconstpointer _a,
                     gconstpointer _b)
{
  const IconInfoKey *a = _a;
  const IconInfoKey *b = _b;
  int i;

  if (a->size != b->size)
    return FALSE;

  if (a->scale != b->scale)
    return FALSE;

  if (a->flags != b->flags)
    return FALSE;

  for (i = 0;
       a->icon_names[i] != NULL &&
       b->icon_names[i] != NULL; i++)
    {
      if (strcmp (a->icon_names[i], b->icon_names[i]) != 0)
        return FALSE;
    }

  return a->icon_names[i] == NULL && b->icon_names[i] == NULL;
}

G_DEFINE_TYPE_WITH_PRIVATE (GtkIconTheme, gtk_icon_theme, G_TYPE_OBJECT)

/**
 * gtk_icon_theme_new:
 * 
 * Creates a new icon theme object. Icon theme objects are used
 * to lookup up an icon by name in a particular icon theme.
 * Usually, you’ll want to use gtk_icon_theme_get_default()
 * or gtk_icon_theme_get_for_screen() rather than creating
 * a new icon theme object for scratch.
 * 
 * Returns: the newly created #GtkIconTheme object.
 *
 * Since: 2.4
 */
GtkIconTheme *
gtk_icon_theme_new (void)
{
  return g_object_new (GTK_TYPE_ICON_THEME, NULL);
}

/**
 * gtk_icon_theme_get_default:
 * 
 * Gets the icon theme for the default screen. See
 * gtk_icon_theme_get_for_screen().
 *
 * Returns: (transfer none): A unique #GtkIconTheme associated with
 *     the default screen. This icon theme is associated with
 *     the screen and can be used as long as the screen
 *     is open. Do not ref or unref it.
 *
 * Since: 2.4
 */
GtkIconTheme *
gtk_icon_theme_get_default (void)
{
  return gtk_icon_theme_get_for_screen (gdk_screen_get_default ());
}

/**
 * gtk_icon_theme_get_for_screen:
 * @screen: a #GdkScreen
 * 
 * Gets the icon theme object associated with @screen; if this
 * function has not previously been called for the given
 * screen, a new icon theme object will be created and
 * associated with the screen. Icon theme objects are
 * fairly expensive to create, so using this function
 * is usually a better choice than calling than gtk_icon_theme_new()
 * and setting the screen yourself; by using this function
 * a single icon theme object will be shared between users.
 *
 * Returns: (transfer none): A unique #GtkIconTheme associated with
 *  the given screen. This icon theme is associated with
 *  the screen and can be used as long as the screen
 *  is open. Do not ref or unref it.
 *
 * Since: 2.4
 */
GtkIconTheme *
gtk_icon_theme_get_for_screen (GdkScreen *screen)
{
  GtkIconTheme *icon_theme;

  g_return_val_if_fail (GDK_IS_SCREEN (screen), NULL);

  icon_theme = g_object_get_data (G_OBJECT (screen), "gtk-icon-theme");
  if (!icon_theme)
    {
      GtkIconThemePrivate *priv;

      icon_theme = gtk_icon_theme_new ();
      gtk_icon_theme_set_screen (icon_theme, screen);

      priv = icon_theme->priv;
      priv->is_screen_singleton = TRUE;

      g_object_set_data (G_OBJECT (screen), I_("gtk-icon-theme"), icon_theme);
    }

  return icon_theme;
}

static void
gtk_icon_theme_class_init (GtkIconThemeClass *klass)
{
  GObjectClass *gobject_class = G_OBJECT_CLASS (klass);

  gobject_class->finalize = gtk_icon_theme_finalize;

  /**
   * GtkIconTheme::changed:
   * @icon_theme: the icon theme
   *
   * Emitted when the current icon theme is switched or GTK+ detects
   * that a change has occurred in the contents of the current
   * icon theme.
   */
  signal_changed = g_signal_new (I_("changed"),
                                 G_TYPE_FROM_CLASS (klass),
                                 G_SIGNAL_RUN_LAST,
                                 G_STRUCT_OFFSET (GtkIconThemeClass, changed),
                                 NULL, NULL,
                                 g_cclosure_marshal_VOID__VOID,
                                 G_TYPE_NONE, 0);
}


/* Callback when the display that the icon theme is attached
 * to is closed; unset the screen, and if it’s the unique theme
 * for the screen, drop the reference
 */
static void
display_closed (GdkDisplay   *display,
                gboolean      is_error,
                GtkIconTheme *icon_theme)
{
  GtkIconThemePrivate *priv = icon_theme->priv;
  GdkScreen *screen = priv->screen;
  gboolean was_screen_singleton = priv->is_screen_singleton;

  if (was_screen_singleton)
    {
      g_object_set_data (G_OBJECT (screen), I_("gtk-icon-theme"), NULL);
      priv->is_screen_singleton = FALSE;
    }

  gtk_icon_theme_set_screen (icon_theme, NULL);

  if (was_screen_singleton)
    {
      g_object_unref (icon_theme);
    }
}

static void
update_current_theme (GtkIconTheme *icon_theme)
{
#define theme_changed(_old, _new) \
  ((_old && !_new) || (!_old && _new) || \
   (_old && _new && strcmp (_old, _new) != 0))
  GtkIconThemePrivate *priv = icon_theme->priv;

  if (!priv->custom_theme)
    {
      gchar *theme = NULL;
      gboolean changed = FALSE;

      if (priv->screen)
        {
          GtkSettings *settings = gtk_settings_get_for_screen (priv->screen);
          g_object_get (settings, "gtk-icon-theme-name", &theme, NULL);
        }

      if (theme_changed (priv->current_theme, theme))
        {
          g_free (priv->current_theme);
          priv->current_theme = theme;
          changed = TRUE;
        }
      else
        g_free (theme);

      if (changed)
        do_theme_change (icon_theme);
    }
#undef theme_changed
}

/* Callback when the icon theme GtkSetting changes
 */
static void
theme_changed (GtkSettings  *settings,
               GParamSpec   *pspec,
               GtkIconTheme *icon_theme)
{
  update_current_theme (icon_theme);
}

static void
unset_screen (GtkIconTheme *icon_theme)
{
  GtkIconThemePrivate *priv = icon_theme->priv;
  GtkSettings *settings;
  GdkDisplay *display;
  
  if (priv->screen)
    {
      settings = gtk_settings_get_for_screen (priv->screen);
      display = gdk_screen_get_display (priv->screen);
      
      g_signal_handlers_disconnect_by_func (display,
                                            (gpointer) display_closed,
                                            icon_theme);
      g_signal_handlers_disconnect_by_func (settings,
                                            (gpointer) theme_changed,
                                            icon_theme);

      priv->screen = NULL;
    }
}

/**
 * gtk_icon_theme_set_screen:
 * @icon_theme: a #GtkIconTheme
 * @screen: a #GdkScreen
 * 
 * Sets the screen for an icon theme; the screen is used
 * to track the user’s currently configured icon theme,
 * which might be different for different screens.
 *
 * Since: 2.4
 */
void
gtk_icon_theme_set_screen (GtkIconTheme *icon_theme,
                           GdkScreen    *screen)
{
  GtkIconThemePrivate *priv;
  GtkSettings *settings;
  GdkDisplay *display;

  g_return_if_fail (GTK_ICON_THEME (icon_theme));
  g_return_if_fail (screen == NULL || GDK_IS_SCREEN (screen));

  priv = icon_theme->priv;

  unset_screen (icon_theme);
  
  if (screen)
    {
      display = gdk_screen_get_display (screen);
      settings = gtk_settings_get_for_screen (screen);
      
      priv->screen = screen;
      
      g_signal_connect (display, "closed",
                        G_CALLBACK (display_closed), icon_theme);
      g_signal_connect (settings, "notify::gtk-icon-theme-name",
                        G_CALLBACK (theme_changed), icon_theme);
    }

  update_current_theme (icon_theme);
}

/* Checks whether a loader for SVG files has been registered
 * with GdkPixbuf.
 */
static gboolean
pixbuf_supports_svg (void)
{
  GSList *formats;
  GSList *tmp_list;
  static gint found_svg = -1;

  if (found_svg != -1)
    return found_svg;

  formats = gdk_pixbuf_get_formats ();

  found_svg = FALSE; 
  for (tmp_list = formats; tmp_list && !found_svg; tmp_list = tmp_list->next)
    {
      gchar **mime_types = gdk_pixbuf_format_get_mime_types (tmp_list->data);
      gchar **mime_type;
      
      for (mime_type = mime_types; *mime_type && !found_svg; mime_type++)
        {
          if (strcmp (*mime_type, "image/svg") == 0)
            found_svg = TRUE;
        }

      g_strfreev (mime_types);
    }

  g_slist_free (formats);
  
  return found_svg;
}

/* The icon info was removed from the icon_info_hash hash table */
static void
icon_info_uncached (GtkIconInfo *icon_info)
{
  GtkIconTheme *icon_theme = icon_info->in_cache;

  DEBUG_CACHE (("removing %p (%s %d 0x%x) from cache (icon_them: %p)  (cache size %d)\n",
                icon_info,
                g_strjoinv (",", icon_info->key.icon_names),
                icon_info->key.size, icon_info->key.flags,
                icon_theme,
                icon_theme != NULL ? g_hash_table_size (icon_theme->priv->info_cache) : 0));

  icon_info->in_cache = NULL;

  if (icon_theme != NULL)
    remove_from_lru_cache (icon_theme, icon_info);
}

static void
gtk_icon_theme_init (GtkIconTheme *icon_theme)
{
  GtkIconThemePrivate *priv;
  const gchar * const *xdg_data_dirs;
  int i, j;

  priv = gtk_icon_theme_get_instance_private (icon_theme);
  icon_theme->priv = priv;

  priv->info_cache = g_hash_table_new_full (icon_info_key_hash, icon_info_key_equal, NULL,
                                            (GDestroyNotify)icon_info_uncached);

  priv->custom_theme = FALSE;

  xdg_data_dirs = g_get_system_data_dirs ();
  for (i = 0; xdg_data_dirs[i]; i++) ;

  priv->search_path_len = 2 * i + 2;
  
  priv->search_path = g_new (char *, priv->search_path_len);
  
  i = 0;
  priv->search_path[i++] = g_build_filename (g_get_user_data_dir (), "icons", NULL);
  priv->search_path[i++] = g_build_filename (g_get_home_dir (), ".icons", NULL);
  
  for (j = 0; xdg_data_dirs[j]; j++) 
    priv->search_path[i++] = g_build_filename (xdg_data_dirs[j], "icons", NULL);

  for (j = 0; xdg_data_dirs[j]; j++) 
    priv->search_path[i++] = g_build_filename (xdg_data_dirs[j], "pixmaps", NULL);

  priv->resource_paths = g_list_append (NULL, g_strdup ("/org/gtk/libgtk/icons"));

  priv->themes_valid = FALSE;
  priv->themes = NULL;
  priv->unthemed_icons = NULL;
  
  priv->pixbuf_supports_svg = pixbuf_supports_svg ();
}

static void
free_dir_mtime (IconThemeDirMtime *dir_mtime)
{
  if (dir_mtime->cache)
    _gtk_icon_cache_unref (dir_mtime->cache);

  g_free (dir_mtime->dir);
  g_slice_free (IconThemeDirMtime, dir_mtime);
}

static gboolean
theme_changed_idle (gpointer user_data)
{
  GtkIconTheme *icon_theme;
  GtkIconThemePrivate *priv;

  icon_theme = GTK_ICON_THEME (user_data);
  priv = icon_theme->priv;

  g_signal_emit (icon_theme, signal_changed, 0);

  if (priv->screen && priv->is_screen_singleton)
    gtk_style_context_reset_widgets (priv->screen);

  priv->theme_changed_idle = 0;

  return FALSE;
}

static void
queue_theme_changed (GtkIconTheme *icon_theme)
{
  GtkIconThemePrivate *priv = icon_theme->priv;

  if (!priv->theme_changed_idle)
    {
      priv->theme_changed_idle =
        gdk_threads_add_idle_full (GTK_PRIORITY_RESIZE - 2,
                                   theme_changed_idle, icon_theme, NULL);
      g_source_set_name_by_id (priv->theme_changed_idle, "[gtk+] theme_changed_idle");
    }
}

static void
do_theme_change (GtkIconTheme *icon_theme)
{
  GtkIconThemePrivate *priv = icon_theme->priv;

  g_hash_table_remove_all (priv->info_cache);

  if (!priv->themes_valid)
    return;

  GTK_NOTE (ICONTHEME,
            g_message ("change to icon theme \"%s\"", priv->current_theme));
  blow_themes (icon_theme);

  queue_theme_changed (icon_theme);

}

static void
blow_themes (GtkIconTheme *icon_theme)
{
  GtkIconThemePrivate *priv = icon_theme->priv;
  
  if (priv->themes_valid)
    {
      g_list_free_full (priv->themes, (GDestroyNotify) theme_destroy);
      g_list_free_full (priv->dir_mtimes, (GDestroyNotify) free_dir_mtime);
      g_hash_table_destroy (priv->unthemed_icons);
    }
  priv->themes = NULL;
  priv->unthemed_icons = NULL;
  priv->dir_mtimes = NULL;
  priv->themes_valid = FALSE;
}

static void
gtk_icon_theme_finalize (GObject *object)
{
  GtkIconTheme *icon_theme;
  GtkIconThemePrivate *priv;
  int i;

  icon_theme = GTK_ICON_THEME (object);
  priv = icon_theme->priv;

  g_hash_table_destroy (priv->info_cache);
  g_assert (priv->info_cache_lru == NULL);

  if (priv->theme_changed_idle)
    g_source_remove (priv->theme_changed_idle);

  unset_screen (icon_theme);

  g_free (priv->current_theme);

  for (i = 0; i < priv->search_path_len; i++)
    g_free (priv->search_path[i]);
  g_free (priv->search_path);

  g_list_free_full (priv->resource_paths, g_free);

  blow_themes (icon_theme);

  G_OBJECT_CLASS (gtk_icon_theme_parent_class)->finalize (object);  
}

/**
 * gtk_icon_theme_set_search_path:
 * @icon_theme: a #GtkIconTheme
 * @path: (array length=n_elements) (element-type filename): array of
 *     directories that are searched for icon themes
 * @n_elements: number of elements in @path.
 * 
 * Sets the search path for the icon theme object. When looking
 * for an icon theme, GTK+ will search for a subdirectory of
 * one or more of the directories in @path with the same name
 * as the icon theme containing an index.theme file. (Themes from
 * multiple of the path elements are combined to allow themes to be
 * extended by adding icons in the user’s home directory.)
 *
 * In addition if an icon found isn’t found either in the current
 * icon theme or the default icon theme, and an image file with
 * the right name is found directly in one of the elements of
 * @path, then that image will be used for the icon name.
 * (This is legacy feature, and new icons should be put
 * into the fallback icon theme, which is called hicolor,
 * rather than directly on the icon path.)
 *
 * Since: 2.4
 */
void
gtk_icon_theme_set_search_path (GtkIconTheme *icon_theme,
                                const gchar  *path[],
                                gint          n_elements)
{
  GtkIconThemePrivate *priv;
  gint i;

  g_return_if_fail (GTK_IS_ICON_THEME (icon_theme));

  priv = icon_theme->priv;
  for (i = 0; i < priv->search_path_len; i++)
    g_free (priv->search_path[i]);

  g_free (priv->search_path);

  priv->search_path = g_new (gchar *, n_elements);
  priv->search_path_len = n_elements;

  for (i = 0; i < priv->search_path_len; i++)
    priv->search_path[i] = g_strdup (path[i]);

  do_theme_change (icon_theme);
}

/**
 * gtk_icon_theme_get_search_path:
 * @icon_theme: a #GtkIconTheme
 * @path: (allow-none) (array length=n_elements) (element-type filename) (out):
 *     location to store a list of icon theme path directories or %NULL.
 *     The stored value should be freed with g_strfreev().
 * @n_elements: location to store number of elements in @path, or %NULL
 *
 * Gets the current search path. See gtk_icon_theme_set_search_path().
 *
 * Since: 2.4
 */
void
gtk_icon_theme_get_search_path (GtkIconTheme  *icon_theme,
                                gchar        **path[],
                                gint          *n_elements)
{
  GtkIconThemePrivate *priv;
  gint i;

  g_return_if_fail (GTK_IS_ICON_THEME (icon_theme));

  priv = icon_theme->priv;

  if (n_elements)
    *n_elements = priv->search_path_len;
  
  if (path)
    {
      *path = g_new (gchar *, priv->search_path_len + 1);
      for (i = 0; i < priv->search_path_len; i++)
        (*path)[i] = g_strdup (priv->search_path[i]);
      (*path)[i] = NULL;
    }
}

/**
 * gtk_icon_theme_append_search_path:
 * @icon_theme: a #GtkIconTheme
 * @path: (type filename): directory name to append to the icon path
 * 
 * Appends a directory to the search path. 
 * See gtk_icon_theme_set_search_path(). 
 *
 * Since: 2.4
 */
void
gtk_icon_theme_append_search_path (GtkIconTheme *icon_theme,
                                   const gchar  *path)
{
  GtkIconThemePrivate *priv;

  g_return_if_fail (GTK_IS_ICON_THEME (icon_theme));
  g_return_if_fail (path != NULL);

  priv = icon_theme->priv;
  
  priv->search_path_len++;

  priv->search_path = g_renew (gchar *, priv->search_path, priv->search_path_len);
  priv->search_path[priv->search_path_len-1] = g_strdup (path);

  do_theme_change (icon_theme);
}

/**
 * gtk_icon_theme_prepend_search_path:
 * @icon_theme: a #GtkIconTheme
 * @path: (type filename): directory name to prepend to the icon path
 * 
 * Prepends a directory to the search path. 
 * See gtk_icon_theme_set_search_path().
 *
 * Since: 2.4
 */
void
gtk_icon_theme_prepend_search_path (GtkIconTheme *icon_theme,
                                    const gchar  *path)
{
  GtkIconThemePrivate *priv;
  gint i;

  g_return_if_fail (GTK_IS_ICON_THEME (icon_theme));
  g_return_if_fail (path != NULL);

  priv = icon_theme->priv;
  
  priv->search_path_len++;
  priv->search_path = g_renew (gchar *, priv->search_path, priv->search_path_len);

  for (i = priv->search_path_len - 1; i > 0; i--)
    priv->search_path[i] = priv->search_path[i - 1];
  
  priv->search_path[0] = g_strdup (path);

  do_theme_change (icon_theme);
}

/**
 * gtk_icon_theme_add_resource_path:
 * @icon_theme: a #GtkIconTheme
 * @path: a resource path
 *
 * Adds a resource path that will be looked at when looking
 * for icons, similar to search paths.
 *
 * This function should be used to make application-specific icons
 * available as part of the icon theme.
 *
 * The resources are considered as part of the hicolor icon theme
 * and must be located in subdirectories that are defined in the
 * hicolor icon theme, such as `@path/16x16/actions/run.png`.
 * Icons that are directly placed in the resource path instead
 * of a subdirectory are also considered as ultimate fallback.
 *
 * Since: 3.14
 */
void
gtk_icon_theme_add_resource_path (GtkIconTheme *icon_theme,
                                  const gchar  *path)
{
  GtkIconThemePrivate *priv = icon_theme->priv;

  g_return_if_fail (GTK_IS_ICON_THEME (icon_theme));
  g_return_if_fail (path != NULL);

  priv->resource_paths = g_list_append (priv->resource_paths, g_strdup (path));

  do_theme_change (icon_theme);
}

/**
 * gtk_icon_theme_set_custom_theme:
 * @icon_theme: a #GtkIconTheme
 * @theme_name: (allow-none): name of icon theme to use instead of
 *   configured theme, or %NULL to unset a previously set custom theme
 * 
 * Sets the name of the icon theme that the #GtkIconTheme object uses
 * overriding system configuration. This function cannot be called
 * on the icon theme objects returned from gtk_icon_theme_get_default()
 * and gtk_icon_theme_get_for_screen().
 *
 * Since: 2.4
 */
void
gtk_icon_theme_set_custom_theme (GtkIconTheme *icon_theme,
                                 const gchar  *theme_name)
{
  GtkIconThemePrivate *priv;

  g_return_if_fail (GTK_IS_ICON_THEME (icon_theme));

  priv = icon_theme->priv;

  g_return_if_fail (!priv->is_screen_singleton);
  
  if (theme_name != NULL)
    {
      priv->custom_theme = TRUE;
      if (!priv->current_theme || strcmp (theme_name, priv->current_theme) != 0)
        {
          g_free (priv->current_theme);
          priv->current_theme = g_strdup (theme_name);

          do_theme_change (icon_theme);
        }
    }
  else
    {
      if (priv->custom_theme)
        {
          priv->custom_theme = FALSE;
          update_current_theme (icon_theme);
        }
    }
}

static const gchar builtin_hicolor_index[] =
"[Icon Theme]\n"
"Name=Hicolor\n"
"Hidden=True\n"
"Directories=16x16/actions,16x16/status,22x22/actions,24x24/actions,24x24/status,32x32/actions,32x32/status,48x48/status,64x64/actions\n"
"[16x16/actions]\n"
"Size=16\n"
"Type=Threshold\n"
"[16x16/status]\n"
"Size=16\n"
"Type=Threshold\n"
"[22x22/actions]\n"
"Size=22\n"
"Type=Threshold\n"
"[24x24/actions]\n"
"Size=24\n"
"Type=Threshold\n"
"[24x24/status]\n"
"Size=24\n"
"Type=Threshold\n"
"[32x32/actions]\n"
"Size=32\n"
"Type=Threshold\n"
"[32x32/status]\n"
"Size=32\n"
"Type=Threshold\n"
"[48x48/status]\n"
"Size=48\n"
"Type=Threshold\n"
"[64x64/actions]\n"
"Size=64\n"
"Type=Threshold\n";

static void
insert_theme (GtkIconTheme *icon_theme,
              const gchar  *theme_name)
{
  gint i;
  GList *l;
  gchar **dirs;
  gchar **scaled_dirs;
  gchar **themes;
  GtkIconThemePrivate *priv;
  IconTheme *theme = NULL;
  gchar *path;
  GKeyFile *theme_file;
  GError *error = NULL;
  IconThemeDirMtime *dir_mtime;
  GStatBuf stat_buf;
  
  priv = icon_theme->priv;

  for (l = priv->themes; l != NULL; l = l->next)
    {
      theme = l->data;
      if (strcmp (theme->name, theme_name) == 0)
        return;
    }
  
  for (i = 0; i < priv->search_path_len; i++)
    {
      path = g_build_filename (priv->search_path[i],
                               theme_name,
                               NULL);
      dir_mtime = g_slice_new (IconThemeDirMtime);
      dir_mtime->cache = NULL;
      dir_mtime->dir = path;
      if (g_stat (path, &stat_buf) == 0 && S_ISDIR (stat_buf.st_mode)) {
        dir_mtime->mtime = stat_buf.st_mtime;
        dir_mtime->exists = TRUE;
      } else {
        dir_mtime->mtime = 0;
        dir_mtime->exists = FALSE;
      }

      priv->dir_mtimes = g_list_prepend (priv->dir_mtimes, dir_mtime);
    }
  priv->dir_mtimes = g_list_reverse (priv->dir_mtimes);

  theme_file = NULL;
  for (i = 0; i < priv->search_path_len && !theme_file; i++)
    {
      path = g_build_filename (priv->search_path[i],
                               theme_name,
                               "index.theme",
                               NULL);
      if (g_file_test (path, G_FILE_TEST_IS_REGULAR)) 
        {
          theme_file = g_key_file_new ();
          g_key_file_set_list_separator (theme_file, ',');
          if (!g_key_file_load_from_file (theme_file, path, 0, &error))
            {
              g_key_file_free (theme_file);
              theme_file = NULL;
              g_error_free (error);
              error = NULL;
            }
        }
      g_free (path);
    }

  if (theme_file || strcmp (theme_name, FALLBACK_ICON_THEME) == 0)
    {
      theme = g_new0 (IconTheme, 1);
      theme->name = g_strdup (theme_name);
      priv->themes = g_list_prepend (priv->themes, theme);
      if (!theme_file)
        {
          theme_file = g_key_file_new ();
          g_key_file_set_list_separator (theme_file, ',');
          g_key_file_load_from_data (theme_file, builtin_hicolor_index, -1, 0, NULL);
        }
    }

  if (theme_file == NULL)
    return;

  theme->display_name = 
    g_key_file_get_locale_string (theme_file, "Icon Theme", "Name", NULL, NULL);
  if (!theme->display_name)
    g_warning ("Theme file for %s has no name", theme_name);

  dirs = g_key_file_get_string_list (theme_file, "Icon Theme", "Directories", NULL, NULL);
  if (!dirs)
    {
      g_warning ("Theme file for %s has no directories", theme_name);
      priv->themes = g_list_remove (priv->themes, theme);
      g_free (theme->name);
      g_free (theme->display_name);
      g_free (theme);
      g_key_file_free (theme_file);
      return;
    }

  scaled_dirs = g_key_file_get_string_list (theme_file, "Icon Theme", "ScaledDirectories", NULL, NULL);

  theme->comment = 
    g_key_file_get_locale_string (theme_file, 
                                  "Icon Theme", "Comment",
                                  NULL, NULL);
  theme->example = 
    g_key_file_get_string (theme_file, 
                           "Icon Theme", "Example",
                           NULL);

  theme->dirs = NULL;
  for (i = 0; dirs[i] != NULL; i++)
    theme_subdir_load (icon_theme, theme, theme_file, dirs[i]);

  if (scaled_dirs)
    {
      for (i = 0; scaled_dirs[i] != NULL; i++)
        theme_subdir_load (icon_theme, theme, theme_file, scaled_dirs[i]);
    }
  g_strfreev (dirs);
  g_strfreev (scaled_dirs);

  theme->dirs = g_list_reverse (theme->dirs);

  themes = g_key_file_get_string_list (theme_file,
                                       "Icon Theme",
                                       "Inherits",
                                       NULL,
                                       NULL);
  if (themes)
    {
      for (i = 0; themes[i] != NULL; i++)
        insert_theme (icon_theme, themes[i]);
      
      g_strfreev (themes);
    }

  g_key_file_free (theme_file);
}

static void
free_unthemed_icon (UnthemedIcon *unthemed_icon)
{
  g_free (unthemed_icon->svg_filename);
  g_free (unthemed_icon->no_svg_filename);
  g_slice_free (UnthemedIcon, unthemed_icon);
}

static gchar *
strip_suffix (const gchar *filename)
{
  const gchar *dot;

  if (g_str_has_suffix (filename, ".symbolic.png"))
    return g_strndup (filename, strlen(filename)-13);

  dot = strrchr (filename, '.');

  if (dot == NULL)
    return g_strdup (filename);

  return g_strndup (filename, dot - filename);
}

static void
add_unthemed_icon (GtkIconTheme *icon_theme,
                   const gchar  *dir,
                   const gchar  *file,
                   gboolean      is_resource)
{
  GtkIconThemePrivate *priv = icon_theme->priv;
  IconSuffix new_suffix, old_suffix;
  gchar *abs_file;
  gchar *base_name;
  UnthemedIcon *unthemed_icon;

  new_suffix = suffix_from_name (file);

  if (new_suffix == ICON_SUFFIX_NONE)
    return;

  abs_file = g_build_filename (dir, file, NULL);
  base_name = strip_suffix (file);

  unthemed_icon = g_hash_table_lookup (priv->unthemed_icons, base_name);

  if (unthemed_icon)
    {
      if (new_suffix == ICON_SUFFIX_SVG)
        {
          if (unthemed_icon->svg_filename)
            g_free (abs_file);
          else
            unthemed_icon->svg_filename = abs_file;
        }
      else
        {
          if (unthemed_icon->no_svg_filename)
            {
              old_suffix = suffix_from_name (unthemed_icon->no_svg_filename);
              if (new_suffix > old_suffix)
                {
                  g_free (unthemed_icon->no_svg_filename);
                  unthemed_icon->no_svg_filename = abs_file;
                }
              else
                g_free (abs_file);
            }
          else
            unthemed_icon->no_svg_filename = abs_file;
        }

      g_free (base_name);
    }
  else
    {
      unthemed_icon = g_slice_new0 (UnthemedIcon);

      unthemed_icon->is_resource = is_resource;

      if (new_suffix == ICON_SUFFIX_SVG)
        unthemed_icon->svg_filename = abs_file;
      else
        unthemed_icon->no_svg_filename = abs_file;

      /* takes ownership of base_name */
      g_hash_table_replace (priv->unthemed_icons, base_name, unthemed_icon);
    }
}

static void
load_themes (GtkIconTheme *icon_theme)
{
  GtkIconThemePrivate *priv;
  GDir *gdir;
  gint base;
  gchar *dir;
  const gchar *file;
  GTimeVal tv;
  IconThemeDirMtime *dir_mtime;
  GStatBuf stat_buf;
  GList *d;
  
  priv = icon_theme->priv;

  if (priv->current_theme)
    insert_theme (icon_theme, priv->current_theme);

  /* Always look in the Adwaita, gnome and hicolor icon themes.
   * Looking in hicolor is mandated by the spec, looking in Adwaita
   * and gnome is a pragmatic solution to prevent missing icons in
   * GTK+ applications when run under, e.g. KDE.
   */
  insert_theme (icon_theme, DEFAULT_ICON_THEME);
  insert_theme (icon_theme, "gnome");
  insert_theme (icon_theme, FALLBACK_ICON_THEME);
  priv->themes = g_list_reverse (priv->themes);


  priv->unthemed_icons = g_hash_table_new_full (g_str_hash, g_str_equal,
                                                g_free, (GDestroyNotify)free_unthemed_icon);

  for (base = 0; base < icon_theme->priv->search_path_len; base++)
    {
      dir = icon_theme->priv->search_path[base];

      dir_mtime = g_slice_new (IconThemeDirMtime);
      priv->dir_mtimes = g_list_append (priv->dir_mtimes, dir_mtime);
      
      dir_mtime->dir = g_strdup (dir);
      dir_mtime->mtime = 0;
      dir_mtime->exists = FALSE;
      dir_mtime->cache = NULL;

      if (g_stat (dir, &stat_buf) != 0 || !S_ISDIR (stat_buf.st_mode))
        continue;
      dir_mtime->mtime = stat_buf.st_mtime;
      dir_mtime->exists = TRUE;

      dir_mtime->cache = _gtk_icon_cache_new_for_path (dir);
      if (dir_mtime->cache != NULL)
        continue;

      gdir = g_dir_open (dir, 0, NULL);
      if (gdir == NULL)
        continue;

      while ((file = g_dir_read_name (gdir)))
        add_unthemed_icon (icon_theme, dir, file, FALSE);

      g_dir_close (gdir);
    }

  for (d = priv->resource_paths; d; d = d->next)
    {
      gchar **children;
      gint i;

      dir = d->data;
      children = g_resources_enumerate_children (dir, 0, NULL);
      if (!children)
        continue;

      for (i = 0; children[i]; i++)
        add_unthemed_icon (icon_theme, dir, children[i], TRUE);

      g_strfreev (children);
    }

  priv->themes_valid = TRUE;
  
  g_get_current_time (&tv);
  priv->last_stat_time = tv.tv_sec;

  GTK_NOTE (ICONTHEME, {
    GList *l;
    GString *s;
    s = g_string_new ("Current icon themes ");
    for (l = icon_theme->priv->themes; l; l = l->next)
      {
        IconTheme *theme = l->data;
        g_string_append (s, theme->name);
        g_string_append_c (s, ' ');
      }
    g_message ("%s", s->str);
    g_string_free (s, TRUE);
  });
}

static void
ensure_valid_themes (GtkIconTheme *icon_theme)
{
  GtkIconThemePrivate *priv = icon_theme->priv;
  GTimeVal tv;
  gboolean was_valid = priv->themes_valid;

  if (priv->loading_themes)
    return;
  priv->loading_themes = TRUE;

  if (priv->themes_valid)
    {
      g_get_current_time (&tv);

      if (ABS (tv.tv_sec - priv->last_stat_time) > 5 &&
          rescan_themes (icon_theme))
        {
          g_hash_table_remove_all (priv->info_cache);
          blow_themes (icon_theme);
        }
    }
  
  if (!priv->themes_valid)
    {
      load_themes (icon_theme);

      if (was_valid)
        queue_theme_changed (icon_theme);
    }

  priv->loading_themes = FALSE;
}

/* The LRU cache is a short list of IconInfos that are kept
 * alive even though their IconInfo would otherwise have
 * been freed, so that we can avoid reloading these
 * constantly.
 * We put infos on the lru list when nothing otherwise
 * references the info. So, when we get a cache hit
 * we remove it from the list, and when the proxy
 * pixmap is released we put it on the list.
 */
static void
ensure_lru_cache_space (GtkIconTheme *icon_theme)
{
  GtkIconThemePrivate *priv = icon_theme->priv;
  GList *l;

  /* Remove last item if LRU full */
  l = g_list_nth (priv->info_cache_lru, INFO_CACHE_LRU_SIZE - 1);
  if (l)
    {
      GtkIconInfo *icon_info = l->data;

      DEBUG_CACHE (("removing (due to out of space) %p (%s %d 0x%x) from LRU cache (cache size %d)\n",
                    icon_info,
                    g_strjoinv (",", icon_info->key.icon_names),
                    icon_info->key.size, icon_info->key.flags,
                    g_list_length (priv->info_cache_lru)));

      priv->info_cache_lru = g_list_delete_link (priv->info_cache_lru, l);
      g_object_unref (icon_info);
    }
}

static void
add_to_lru_cache (GtkIconTheme *icon_theme,
                  GtkIconInfo  *icon_info)
{
  GtkIconThemePrivate *priv = icon_theme->priv;

  DEBUG_CACHE (("adding  %p (%s %d 0x%x) to LRU cache (cache size %d)\n",
                icon_info,
                g_strjoinv (",", icon_info->key.icon_names),
                icon_info->key.size, icon_info->key.flags,
                g_list_length (priv->info_cache_lru)));

  g_assert (g_list_find (priv->info_cache_lru, icon_info) == NULL);

  ensure_lru_cache_space (icon_theme);
  /* prepend new info to LRU */
  priv->info_cache_lru = g_list_prepend (priv->info_cache_lru,
                                         g_object_ref (icon_info));
}

static void
ensure_in_lru_cache (GtkIconTheme *icon_theme,
                     GtkIconInfo  *icon_info)
{
  GtkIconThemePrivate *priv = icon_theme->priv;
  GList *l;

  l = g_list_find (priv->info_cache_lru, icon_info);
  if (l)
    {
      /* Move to front of LRU if already in it */
      priv->info_cache_lru = g_list_remove_link (priv->info_cache_lru, l);
      priv->info_cache_lru = g_list_concat (l, priv->info_cache_lru);
    }
  else
    add_to_lru_cache (icon_theme, icon_info);
}

static void
remove_from_lru_cache (GtkIconTheme *icon_theme,
                       GtkIconInfo  *icon_info)
{
  GtkIconThemePrivate *priv = icon_theme->priv;
  if (g_list_find (priv->info_cache_lru, icon_info))
    {
      DEBUG_CACHE (("removing %p (%s %d 0x%x) from LRU cache (cache size %d)\n",
                    icon_info,
                    g_strjoinv (",", icon_info->key.icon_names),
                    icon_info->key.size, icon_info->key.flags,
                    g_list_length (priv->info_cache_lru)));

      priv->info_cache_lru = g_list_remove (priv->info_cache_lru, icon_info);
      g_object_unref (icon_info);
    }
}

static SymbolicPixbufCache *
symbolic_pixbuf_cache_new (GdkPixbuf           *pixbuf,
                           const GdkRGBA       *fg,
                           const GdkRGBA       *success_color,
                           const GdkRGBA       *warning_color,
                           const GdkRGBA       *error_color,
                           SymbolicPixbufCache *next)
{
  SymbolicPixbufCache *cache;

  cache = g_new0 (SymbolicPixbufCache, 1);
  cache->pixbuf = g_object_ref (pixbuf);
  if (fg)
    cache->fg = *fg;
  if (success_color)
    cache->success_color = *success_color;
  if (warning_color)
    cache->warning_color = *warning_color;
  if (error_color)
    cache->error_color = *error_color;
  cache->next = next;
  return cache;
}

static gboolean
rgba_matches (const GdkRGBA *a,
              const GdkRGBA *b)
{
  GdkRGBA transparent = { 0 };

  /* For matching we treat unset colors as transparent rather
     than default, which works as well, because transparent
     will never be used for real symbolic icon colors */
  if (a == NULL)
    a = &transparent;

  return
    fabs(a->red - b->red) < 0.0001 &&
    fabs(a->green - b->green) < 0.0001 &&
    fabs(a->blue - b->blue) < 0.0001 &&
    fabs(a->alpha - b->alpha) < 0.0001;
}

static SymbolicPixbufCache *
symbolic_pixbuf_cache_matches (SymbolicPixbufCache *cache,
                               const GdkRGBA       *fg,
                               const GdkRGBA       *success_color,
                               const GdkRGBA       *warning_color,
                               const GdkRGBA       *error_color)
{
  while (cache != NULL)
    {
      if (rgba_matches (fg, &cache->fg) &&
          rgba_matches (success_color, &cache->success_color) &&
          rgba_matches (warning_color, &cache->warning_color) &&
          rgba_matches (error_color, &cache->error_color))
        return cache;

      cache = cache->next;
    }

  return NULL;
}

static void
symbolic_pixbuf_cache_free (SymbolicPixbufCache *cache)
{
  SymbolicPixbufCache *next;

  while (cache != NULL)
    {
      next = cache->next;
      g_object_unref (cache->pixbuf);
      g_free (cache);

      cache = next;
    }
}

static gboolean
icon_name_is_symbolic (const gchar *icon_name)
{
  return g_str_has_suffix (icon_name, "-symbolic")
      || g_str_has_suffix (icon_name, "-symbolic-ltr")
      || g_str_has_suffix (icon_name, "-symbolic-rtl");
}

static gboolean
icon_uri_is_symbolic (const gchar *icon_name)
{
  return g_str_has_suffix (icon_name, "-symbolic.svg")
      || g_str_has_suffix (icon_name, "-symbolic-ltr.svg")
      || g_str_has_suffix (icon_name, "-symbolic-rtl.svg")
      || g_str_has_suffix (icon_name, ".symbolic.png");
}

static GtkIconInfo *
real_choose_icon (GtkIconTheme       *icon_theme,
                  const gchar        *icon_names[],
                  gint                size,
                  gint                scale,
                  GtkIconLookupFlags  flags)
{
  GtkIconThemePrivate *priv;
  GList *l;
  GtkIconInfo *icon_info = NULL;
  GtkIconInfo *unscaled_icon_info;
  UnthemedIcon *unthemed_icon = NULL;
  const gchar *icon_name = NULL;
  gboolean allow_svg;
  gboolean use_builtin;
  IconTheme *theme = NULL;
  gint i;
  IconInfoKey key;

  priv = icon_theme->priv;

  ensure_valid_themes (icon_theme);

  key.icon_names = (gchar **)icon_names;
  key.size = size;
  key.scale = scale;
  key.flags = flags;

  icon_info = g_hash_table_lookup (priv->info_cache, &key);
  if (icon_info != NULL)
    {
      DEBUG_CACHE (("cache hit %p (%s %d 0x%x) (cache size %d)\n",
                    icon_info,
                    g_strjoinv (",", icon_info->key.icon_names),
                    icon_info->key.size, icon_info->key.flags,
                    g_hash_table_size (priv->info_cache)));

      icon_info = g_object_ref (icon_info);
      remove_from_lru_cache (icon_theme, icon_info);

      return icon_info;
    }

  if (flags & GTK_ICON_LOOKUP_NO_SVG)
    allow_svg = FALSE;
  else if (flags & GTK_ICON_LOOKUP_FORCE_SVG)
    allow_svg = TRUE;
  else
    allow_svg = priv->pixbuf_supports_svg;

  use_builtin = flags & GTK_ICON_LOOKUP_USE_BUILTIN;

  /* This is used in the icontheme unit test */
  GTK_NOTE (ICONTHEME,
            for (i = 0; icon_names[i]; i++)
              g_message ("\tlookup name: %s", icon_names[i]));

  /* For symbolic icons, do a search in all registered themes first;
   * a theme that inherits them from a parent theme might provide
   * an alternative full-color version, but still expect the symbolic icon
   * to show up instead.
   *
   * In other words: We prefer symbolic icons in inherited themes over
   * generic icons in the theme.
   */
  for (l = priv->themes; l; l = l->next)
    {
      theme = l->data;
      for (i = 0; icon_names[i] && icon_name_is_symbolic (icon_names[i]); i++)
        {
          icon_name = icon_names[i];
          icon_info = theme_lookup_icon (theme, icon_name, size, scale, allow_svg, use_builtin);
          if (icon_info)
            goto out;
        }
    }

  for (l = priv->themes; l; l = l->next)
    {
      theme = l->data;

      for (i = 0; icon_names[i]; i++)
        {
          icon_name = icon_names[i];
          icon_info = theme_lookup_icon (theme, icon_name, size, scale, allow_svg, use_builtin);
          if (icon_info)
            goto out;
        }
    }

  theme = NULL;

  for (i = 0; icon_names[i]; i++)
    {
      unthemed_icon = g_hash_table_lookup (priv->unthemed_icons, icon_names[i]);
      if (unthemed_icon)
        break;
    }
#ifdef G_OS_WIN32
  /* Still not found an icon, check if reference to a Win32 resource */
  if (!unthemed_icon)
    {
      gchar **resources;
      HICON hIcon = NULL;
      
      resources = g_strsplit (icon_names[0], ",", 0);
      if (resources[0])
        {
          wchar_t *wfile = g_utf8_to_utf16 (resources[0], -1, NULL, NULL, NULL);
          ExtractIconExW (wfile, resources[1] ? atoi (resources[1]) : 0, &hIcon, NULL, 1);
          g_free (wfile);
        }
      
      if (hIcon)
        {
          icon_info = icon_info_new (ICON_THEME_DIR_UNTHEMED, size, 1);
          icon_info->cache_pixbuf = gdk_win32_icon_to_pixbuf_libgtk_only (hIcon, NULL, NULL);
          DestroyIcon (hIcon);
        }
      g_strfreev (resources);
    }
#endif

  if (unthemed_icon)
    {
      icon_info = icon_info_new (ICON_THEME_DIR_UNTHEMED, size, 1);

      /* A SVG icon, when allowed, beats out a XPM icon, but not a PNG icon */
      if (allow_svg &&
          unthemed_icon->svg_filename &&
          (!unthemed_icon->no_svg_filename ||
           suffix_from_name (unthemed_icon->no_svg_filename) < ICON_SUFFIX_PNG))
        icon_info->filename = g_strdup (unthemed_icon->svg_filename);
      else if (unthemed_icon->no_svg_filename)
        icon_info->filename = g_strdup (unthemed_icon->no_svg_filename);

      if (unthemed_icon->is_resource)
        {
          gchar *uri;
          uri = g_strconcat ("resource://", icon_info->filename, NULL);
          icon_info->icon_file = g_file_new_for_uri (uri);
          g_free (uri);
        }
      else
        icon_info->icon_file = g_file_new_for_path (icon_info->filename);

      icon_info->is_svg = suffix_from_name (icon_info->filename) == ICON_SUFFIX_SVG;
      icon_info->is_resource = unthemed_icon->is_resource;
    }

 out:
  if (icon_info)
    {
      icon_info->desired_size = size;
      icon_info->desired_scale = scale;
      icon_info->forced_size = (flags & GTK_ICON_LOOKUP_FORCE_SIZE) != 0;

      /* In case we're not scaling the icon we want to reuse the exact same
       * size as a scale==1 lookup would be, rather than not scaling at all
       * and causing a different layout
       */
      icon_info->unscaled_scale = 1.0;
      if (scale != 1 && !icon_info->forced_size && theme != NULL)
        {
          unscaled_icon_info = theme_lookup_icon (theme, icon_name, size, 1, allow_svg, use_builtin);
          if (unscaled_icon_info)
            {
              icon_info->unscaled_scale =
                (gdouble) unscaled_icon_info->dir_size * scale / (icon_info->dir_size * icon_info->dir_scale);
              g_object_unref (unscaled_icon_info);
            }
        }

      icon_info->key.icon_names = g_strdupv ((char **)icon_names);
      icon_info->key.size = size;
      icon_info->key.scale = scale;
      icon_info->key.flags = flags;
      icon_info->in_cache = icon_theme;
      DEBUG_CACHE (("adding %p (%s %d 0x%x) to cache (cache size %d)\n",
                    icon_info,
                    g_strjoinv (",", icon_info->key.icon_names),
                    icon_info->key.size, icon_info->key.flags,
                    g_hash_table_size (priv->info_cache)));
     g_hash_table_insert (priv->info_cache, &icon_info->key, icon_info);
    }
  else
    {
      static gboolean check_for_default_theme = TRUE;
      gchar *default_theme_path;
      gboolean found = FALSE;

      if (check_for_default_theme)
        {
          check_for_default_theme = FALSE;

          for (i = 0; !found && i < priv->search_path_len; i++)
            {
              default_theme_path = g_build_filename (priv->search_path[i],
                                                     FALLBACK_ICON_THEME,
                                                     "index.theme",
                                                     NULL);
              found = g_file_test (default_theme_path, G_FILE_TEST_IS_REGULAR);
              g_free (default_theme_path);
            }

          if (!found)
            {
              g_warning ("Could not find the icon '%s'. The '%s' theme\n"
                         "was not found either, perhaps you need to install it.\n"
                         "You can get a copy from:\n"
                         "\t%s",
                         icon_names[0], FALLBACK_ICON_THEME, "http://icon-theme.freedesktop.org/releases");
            }
        }
    }

  return icon_info;
}

static void
icon_name_list_add_icon (GPtrArray   *icons,
                         const gchar *dir_suffix,
                         gchar       *icon_name)
{
  if (dir_suffix)
    g_ptr_array_add (icons, g_strconcat (icon_name, dir_suffix, NULL));
  g_ptr_array_add (icons, icon_name);
}

static GtkIconInfo *
choose_icon (GtkIconTheme       *icon_theme,
             const gchar        *icon_names[],
             gint                size,
             gint                scale,
             GtkIconLookupFlags  flags)
{
  gboolean has_regular = FALSE, has_symbolic = FALSE;
  GtkIconInfo *icon_info;
  GPtrArray *new_names;
  const gchar *dir_suffix;
  guint i;

  if (flags & GTK_ICON_LOOKUP_DIR_LTR)
    dir_suffix = "-ltr";
  else if (flags & GTK_ICON_LOOKUP_DIR_RTL)
    dir_suffix = "-rtl";
  else
    dir_suffix = NULL;

  for (i = 0; icon_names[i]; i++)
    {
      if (icon_name_is_symbolic (icon_names[i]))
        has_symbolic = TRUE;
      else
        has_regular = TRUE;
    }

  if ((flags & GTK_ICON_LOOKUP_FORCE_REGULAR) && has_symbolic)
    {
      new_names = g_ptr_array_new_with_free_func (g_free);
      for (i = 0; icon_names[i]; i++)
        {
          if (icon_name_is_symbolic (icon_names[i]))
            icon_name_list_add_icon (new_names, dir_suffix, g_strndup (icon_names[i], strlen (icon_names[i]) - strlen ("-symbolic")));
          else
            icon_name_list_add_icon (new_names, dir_suffix, g_strdup (icon_names[i]));
        }
      for (i = 0; icon_names[i]; i++)
        {
          if (icon_name_is_symbolic (icon_names[i]))
            icon_name_list_add_icon (new_names, dir_suffix, g_strdup (icon_names[i]));
        }
      g_ptr_array_add (new_names, NULL);

      icon_info = real_choose_icon (icon_theme,
                                    (const gchar **) new_names->pdata,
                                    size,
                                    scale,
                                    flags & ~(GTK_ICON_LOOKUP_FORCE_REGULAR | GTK_ICON_LOOKUP_FORCE_SYMBOLIC));

      g_ptr_array_free (new_names, TRUE);
    }
  else if ((flags & GTK_ICON_LOOKUP_FORCE_SYMBOLIC) && has_regular)
    {
      new_names = g_ptr_array_new_with_free_func (g_free);
      for (i = 0; icon_names[i]; i++)
        {
          if (!icon_name_is_symbolic (icon_names[i]))
            icon_name_list_add_icon (new_names, dir_suffix, g_strconcat (icon_names[i], "-symbolic", NULL));
          else
            icon_name_list_add_icon (new_names, dir_suffix, g_strdup (icon_names[i]));
        }
      for (i = 0; icon_names[i]; i++)
        {
          if (!icon_name_is_symbolic (icon_names[i]))
            icon_name_list_add_icon (new_names, dir_suffix, g_strdup (icon_names[i]));
        }
      g_ptr_array_add (new_names, NULL);

      icon_info = real_choose_icon (icon_theme,
                                    (const gchar **) new_names->pdata,
                                    size,
                                    scale,
                                    flags & ~(GTK_ICON_LOOKUP_FORCE_REGULAR | GTK_ICON_LOOKUP_FORCE_SYMBOLIC));

      g_ptr_array_free (new_names, TRUE);
    }
  else if (dir_suffix)
    {
      new_names = g_ptr_array_new_with_free_func (g_free);
      for (i = 0; icon_names[i]; i++)
        {
          icon_name_list_add_icon (new_names, dir_suffix, g_strdup (icon_names[i]));
        }
      g_ptr_array_add (new_names, NULL);

      icon_info = real_choose_icon (icon_theme,
                                    (const gchar **) new_names->pdata,
                                    size,
                                    scale,
                                    flags & ~(GTK_ICON_LOOKUP_FORCE_REGULAR | GTK_ICON_LOOKUP_FORCE_SYMBOLIC));

      g_ptr_array_free (new_names, TRUE);
    }
  else
    {
      icon_info = real_choose_icon (icon_theme,
                                    icon_names,
                                    size,
                                    scale,
                                    flags & ~(GTK_ICON_LOOKUP_FORCE_REGULAR | GTK_ICON_LOOKUP_FORCE_SYMBOLIC));
    }

  return icon_info;
}

/**
 * gtk_icon_theme_lookup_icon:
 * @icon_theme: a #GtkIconTheme
 * @icon_name: the name of the icon to lookup
 * @size: desired icon size
 * @flags: flags modifying the behavior of the icon lookup
 * 
 * Looks up a named icon and returns a #GtkIconInfo containing
 * information such as the filename of the icon. The icon
 * can then be rendered into a pixbuf using
 * gtk_icon_info_load_icon(). (gtk_icon_theme_load_icon()
 * combines these two steps if all you need is the pixbuf.)
 *
 * When rendering on displays with high pixel densities you should not
 * use a @size multiplied by the scaling factor returned by functions
 * like gdk_window_get_scale_factor(). Instead, you should use
 * gtk_icon_theme_lookup_icon_for_scale(), as the assets loaded
 * for a given scaling factor may be different.
 * 
 * Returns: (nullable) (transfer full): a #GtkIconInfo object
 *     containing information about the icon, or %NULL if the
 *     icon wasn’t found.
 *
 * Since: 2.4
 */
GtkIconInfo *
gtk_icon_theme_lookup_icon (GtkIconTheme       *icon_theme,
                            const gchar        *icon_name,
                            gint                size,
                            GtkIconLookupFlags  flags)
{
  g_return_val_if_fail (GTK_IS_ICON_THEME (icon_theme), NULL);
  g_return_val_if_fail (icon_name != NULL, NULL);
  g_return_val_if_fail ((flags & GTK_ICON_LOOKUP_NO_SVG) == 0 ||
                        (flags & GTK_ICON_LOOKUP_FORCE_SVG) == 0, NULL);

  GTK_NOTE (ICONTHEME, g_message ("looking up icon %s", icon_name));

  return gtk_icon_theme_lookup_icon_for_scale (icon_theme, icon_name,
                                               size, 1, flags);
}

/**
 * gtk_icon_theme_lookup_icon_for_scale:
 * @icon_theme: a #GtkIconTheme
 * @icon_name: the name of the icon to lookup
 * @size: desired icon size
 * @scale: the desired scale
 * @flags: flags modifying the behavior of the icon lookup
 *
 * Looks up a named icon for a particular window scale and returns a
 * #GtkIconInfo containing information such as the filename of the
 * icon. The icon can then be rendered into a pixbuf using
 * gtk_icon_info_load_icon(). (gtk_icon_theme_load_icon() combines
 * these two steps if all you need is the pixbuf.)
 *
 * Returns: (nullable) (transfer full): a #GtkIconInfo object
 *     containing information about the icon, or %NULL if the
 *     icon wasn’t found.
 *
 * Since: 3.10
 */
GtkIconInfo *
gtk_icon_theme_lookup_icon_for_scale (GtkIconTheme       *icon_theme,
                                      const gchar        *icon_name,
                                      gint                size,
                                      gint                scale,
                                      GtkIconLookupFlags  flags)
{
  GtkIconInfo *info;

  g_return_val_if_fail (GTK_IS_ICON_THEME (icon_theme), NULL);
  g_return_val_if_fail (icon_name != NULL, NULL);
  g_return_val_if_fail ((flags & GTK_ICON_LOOKUP_NO_SVG) == 0 ||
                        (flags & GTK_ICON_LOOKUP_FORCE_SVG) == 0, NULL);
  g_return_val_if_fail (scale >= 1, NULL);

  GTK_NOTE (ICONTHEME, g_message ("looking up icon %s for scale %d", icon_name, scale));

  if (flags & GTK_ICON_LOOKUP_GENERIC_FALLBACK)
    {
      gchar **names, **nonsymbolic_names;
      gint dashes, i;
      gchar *p, *nonsymbolic_icon_name;
      gboolean is_symbolic;

      is_symbolic = icon_name_is_symbolic (icon_name);
      if (is_symbolic)
        nonsymbolic_icon_name = g_strndup (icon_name, strlen (icon_name) - strlen ("-symbolic"));
      else
        nonsymbolic_icon_name = g_strdup (icon_name);
 
      dashes = 0;
      for (p = (gchar *) nonsymbolic_icon_name; *p; p++)
        if (*p == '-')
          dashes++;

      nonsymbolic_names = g_new (gchar *, dashes + 2);
      nonsymbolic_names[0] = nonsymbolic_icon_name;

      for (i = 1; i <= dashes; i++)
        {
          nonsymbolic_names[i] = g_strdup (nonsymbolic_names[i - 1]);
          p = strrchr (nonsymbolic_names[i], '-');
          *p = '\0';
        }
      nonsymbolic_names[dashes + 1] = NULL;

      if (is_symbolic)
        {
          names = g_new (gchar *, 2 * dashes + 3);
          for (i = 0; nonsymbolic_names[i] != NULL; i++)
            {
              names[i] = g_strconcat (nonsymbolic_names[i], "-symbolic", NULL);
              names[dashes + 1 + i] = nonsymbolic_names[i];
            }

          names[dashes + 1 + i] = NULL;
          g_free (nonsymbolic_names);
        }
      else
        {
          names = nonsymbolic_names;
        }

      info = choose_icon (icon_theme, (const gchar **) names, size, scale, flags);

      g_strfreev (names);
    }
  else
    {
      const gchar *names[2];

      names[0] = icon_name;
      names[1] = NULL;

      info = choose_icon (icon_theme, names, size, scale, flags);
    }

  return info;
}

/**
 * gtk_icon_theme_choose_icon:
 * @icon_theme: a #GtkIconTheme
 * @icon_names: (array zero-terminated=1): %NULL-terminated array of
 *     icon names to lookup
 * @size: desired icon size
 * @flags: flags modifying the behavior of the icon lookup
 * 
 * Looks up a named icon and returns a #GtkIconInfo containing
 * information such as the filename of the icon. The icon
 * can then be rendered into a pixbuf using
 * gtk_icon_info_load_icon(). (gtk_icon_theme_load_icon()
 * combines these two steps if all you need is the pixbuf.)
 *
 * If @icon_names contains more than one name, this function 
 * tries them all in the given order before falling back to 
 * inherited icon themes.
 * 
 * Returns: (nullable) (transfer full): a #GtkIconInfo object
 * containing information about the icon, or %NULL if the icon wasn’t
 * found.
 *
 * Since: 2.12
 */
GtkIconInfo *
gtk_icon_theme_choose_icon (GtkIconTheme       *icon_theme,
                            const gchar        *icon_names[],
                            gint                size,
                            GtkIconLookupFlags  flags)
{
  g_return_val_if_fail (GTK_IS_ICON_THEME (icon_theme), NULL);
  g_return_val_if_fail (icon_names != NULL, NULL);
  g_return_val_if_fail ((flags & GTK_ICON_LOOKUP_NO_SVG) == 0 ||
                        (flags & GTK_ICON_LOOKUP_FORCE_SVG) == 0, NULL);
  g_warn_if_fail ((flags & GTK_ICON_LOOKUP_GENERIC_FALLBACK) == 0);

  return choose_icon (icon_theme, icon_names, size, 1, flags);
}

/**
 * gtk_icon_theme_choose_icon_for_scale:
 * @icon_theme: a #GtkIconTheme
 * @icon_names: (array zero-terminated=1): %NULL-terminated
 *     array of icon names to lookup
 * @size: desired icon size
 * @scale: desired scale
 * @flags: flags modifying the behavior of the icon lookup
 * 
 * Looks up a named icon for a particular window scale and returns
 * a #GtkIconInfo containing information such as the filename of the
 * icon. The icon can then be rendered into a pixbuf using
 * gtk_icon_info_load_icon(). (gtk_icon_theme_load_icon()
 * combines these two steps if all you need is the pixbuf.)
 *
 * If @icon_names contains more than one name, this function 
 * tries them all in the given order before falling back to 
 * inherited icon themes.
 * 
 * Returns: (nullable) (transfer full): a #GtkIconInfo object
 *     containing information about the icon, or %NULL if the
 *     icon wasn’t found.
 *
 * Since: 3.10
 */
GtkIconInfo *
gtk_icon_theme_choose_icon_for_scale (GtkIconTheme       *icon_theme,
                                      const gchar        *icon_names[],
                                      gint                size,
                                      gint                scale,
                                      GtkIconLookupFlags  flags)
{
  g_return_val_if_fail (GTK_IS_ICON_THEME (icon_theme), NULL);
  g_return_val_if_fail (icon_names != NULL, NULL);
  g_return_val_if_fail ((flags & GTK_ICON_LOOKUP_NO_SVG) == 0 ||
                        (flags & GTK_ICON_LOOKUP_FORCE_SVG) == 0, NULL);
  g_return_val_if_fail (scale >= 1, NULL);
  g_warn_if_fail ((flags & GTK_ICON_LOOKUP_GENERIC_FALLBACK) == 0);

  return choose_icon (icon_theme, icon_names, size, scale, flags);
}


/* Error quark */
GQuark
gtk_icon_theme_error_quark (void)
{
  return g_quark_from_static_string ("gtk-icon-theme-error-quark");
}

/**
 * gtk_icon_theme_load_icon:
 * @icon_theme: a #GtkIconTheme
 * @icon_name: the name of the icon to lookup
 * @size: the desired icon size. The resulting icon may not be
 *     exactly this size; see gtk_icon_info_load_icon().
 * @flags: flags modifying the behavior of the icon lookup
 * @error: (allow-none): Location to store error information on failure,
 *     or %NULL.
 *
 * Looks up an icon in an icon theme, scales it to the given size
 * and renders it into a pixbuf. This is a convenience function;
 * if more details about the icon are needed, use
 * gtk_icon_theme_lookup_icon() followed by gtk_icon_info_load_icon().
 *
 * Note that you probably want to listen for icon theme changes and
 * update the icon. This is usually done by connecting to the
 * GtkWidget::style-set signal. If for some reason you do not want to
 * update the icon when the icon theme changes, you should consider
 * using gdk_pixbuf_copy() to make a private copy of the pixbuf
 * returned by this function. Otherwise GTK+ may need to keep the old
 * icon theme loaded, which would be a waste of memory.
 *
 * Returns: (nullable) (transfer full): the rendered icon; this may be
 *     a newly created icon or a new reference to an internal icon, so
 *     you must not modify the icon. Use g_object_unref() to release
 *     your reference to the icon. %NULL if the icon isn’t found.
 *
 * Since: 2.4
 */
GdkPixbuf *
gtk_icon_theme_load_icon (GtkIconTheme         *icon_theme,
                          const gchar          *icon_name,
                          gint                  size,
                          GtkIconLookupFlags    flags,
                          GError              **error)
{
  g_return_val_if_fail (GTK_IS_ICON_THEME (icon_theme), NULL);
  g_return_val_if_fail (icon_name != NULL, NULL);
  g_return_val_if_fail ((flags & GTK_ICON_LOOKUP_NO_SVG) == 0 ||
                        (flags & GTK_ICON_LOOKUP_FORCE_SVG) == 0, NULL);
  g_return_val_if_fail (error == NULL || *error == NULL, NULL);

  return gtk_icon_theme_load_icon_for_scale (icon_theme, icon_name,
                                             size, 1, flags, error);
}

/**
 * gtk_icon_theme_load_icon_for_scale:
 * @icon_theme: a #GtkIconTheme
 * @icon_name: the name of the icon to lookup
 * @size: the desired icon size. The resulting icon may not be
 *     exactly this size; see gtk_icon_info_load_icon().
 * @scale: desired scale
 * @flags: flags modifying the behavior of the icon lookup
 * @error: (allow-none): Location to store error information on failure,
 *     or %NULL.
 *
 * Looks up an icon in an icon theme for a particular window scale,
 * scales it to the given size and renders it into a pixbuf. This is a
 * convenience function; if more details about the icon are needed,
 * use gtk_icon_theme_lookup_icon() followed by
 * gtk_icon_info_load_icon().
 *
 * Note that you probably want to listen for icon theme changes and
 * update the icon. This is usually done by connecting to the
 * GtkWidget::style-set signal. If for some reason you do not want to
 * update the icon when the icon theme changes, you should consider
 * using gdk_pixbuf_copy() to make a private copy of the pixbuf
 * returned by this function. Otherwise GTK+ may need to keep the old
 * icon theme loaded, which would be a waste of memory.
 *
 * Returns: (nullable) (transfer full): the rendered icon; this may be
 *     a newly created icon or a new reference to an internal icon, so
 *     you must not modify the icon. Use g_object_unref() to release
 *     your reference to the icon. %NULL if the icon isn’t found.
 *
 * Since: 3.10
 */
GdkPixbuf *
gtk_icon_theme_load_icon_for_scale (GtkIconTheme        *icon_theme,
                                    const gchar         *icon_name,
                                    gint                 size,
                                    gint                 scale,
                                    GtkIconLookupFlags   flags,
                                    GError             **error)
{
  GtkIconInfo *icon_info;
  GdkPixbuf *pixbuf = NULL;
  
  g_return_val_if_fail (GTK_IS_ICON_THEME (icon_theme), NULL);
  g_return_val_if_fail (icon_name != NULL, NULL);
  g_return_val_if_fail ((flags & GTK_ICON_LOOKUP_NO_SVG) == 0 ||
                        (flags & GTK_ICON_LOOKUP_FORCE_SVG) == 0, NULL);
  g_return_val_if_fail (error == NULL || *error == NULL, NULL);
  g_return_val_if_fail (scale >= 1, NULL);

  icon_info = gtk_icon_theme_lookup_icon_for_scale (icon_theme, icon_name, size, scale,
                                                    flags | GTK_ICON_LOOKUP_USE_BUILTIN);
  if (!icon_info)
    {
      g_set_error (error, GTK_ICON_THEME_ERROR,  GTK_ICON_THEME_NOT_FOUND,
                   _("Icon “%s” not present in theme %s"), icon_name, icon_theme->priv->current_theme);
      return NULL;
    }

  pixbuf = gtk_icon_info_load_icon (icon_info, error);
  g_prefix_error (error, "Failed to load %s: ", icon_info->filename);
  g_object_unref (icon_info);

  return pixbuf;
}

/**
 * gtk_icon_theme_load_surface:
 * @icon_theme: a #GtkIconTheme
 * @icon_name: the name of the icon to lookup
 * @size: the desired icon size. The resulting icon may not be
 *     exactly this size; see gtk_icon_info_load_icon().
 * @scale: desired scale
 * @for_window: (allow-none): #GdkWindow to optimize drawing for, or %NULL
 * @flags: flags modifying the behavior of the icon lookup
 * @error: (allow-none): Location to store error information on failure,
 *     or %NULL.
 *
 * Looks up an icon in an icon theme for a particular window scale,
 * scales it to the given size and renders it into a cairo surface. This is a
 * convenience function; if more details about the icon are needed,
 * use gtk_icon_theme_lookup_icon() followed by
 * gtk_icon_info_load_surface().
 *
 * Note that you probably want to listen for icon theme changes and
 * update the icon. This is usually done by connecting to the
 * GtkWidget::style-set signal.
 *
 * Returns: (nullable) (transfer full): the rendered icon; this may be
 *     a newly created icon or a new reference to an internal icon, so
 *     you must not modify the icon. Use cairo_surface_destroy() to
 *     release your reference to the icon. %NULL if the icon isn’t
 *     found.
 *
 * Since: 3.10
 */
cairo_surface_t *
gtk_icon_theme_load_surface (GtkIconTheme        *icon_theme,
                             const gchar         *icon_name,
                             gint                 size,
                             gint                 scale,
                             GdkWindow           *for_window,
                             GtkIconLookupFlags   flags,
                             GError             **error)
{
  GtkIconInfo *icon_info;
  cairo_surface_t *surface = NULL;
  
  g_return_val_if_fail (GTK_IS_ICON_THEME (icon_theme), NULL);
  g_return_val_if_fail (icon_name != NULL, NULL);
  g_return_val_if_fail ((flags & GTK_ICON_LOOKUP_NO_SVG) == 0 ||
                        (flags & GTK_ICON_LOOKUP_FORCE_SVG) == 0, NULL);
  g_return_val_if_fail (error == NULL || *error == NULL, NULL);
  g_return_val_if_fail (scale >= 1, NULL);

  icon_info = gtk_icon_theme_lookup_icon_for_scale (icon_theme, icon_name, size, scale,
                                                    flags | GTK_ICON_LOOKUP_USE_BUILTIN);
  if (!icon_info)
    {
      g_set_error (error, GTK_ICON_THEME_ERROR,  GTK_ICON_THEME_NOT_FOUND,
                   _("Icon “%s” not present in theme %s"), icon_name, icon_theme->priv->current_theme);
      return NULL;
    }

  surface = gtk_icon_info_load_surface (icon_info, for_window, error);
  g_object_unref (icon_info);

  return surface;
}

/**
 * gtk_icon_theme_has_icon:
 * @icon_theme: a #GtkIconTheme
 * @icon_name: the name of an icon
 * 
 * Checks whether an icon theme includes an icon
 * for a particular name.
 * 
 * Returns: %TRUE if @icon_theme includes an
 *  icon for @icon_name.
 *
 * Since: 2.4
 */
gboolean 
gtk_icon_theme_has_icon (GtkIconTheme *icon_theme,
                         const gchar  *icon_name)
{
  GtkIconThemePrivate *priv;
  GList *l;

  g_return_val_if_fail (GTK_IS_ICON_THEME (icon_theme), FALSE);
  g_return_val_if_fail (icon_name != NULL, FALSE);

  priv = icon_theme->priv;
  
  ensure_valid_themes (icon_theme);

  for (l = priv->dir_mtimes; l; l = l->next)
    {
      IconThemeDirMtime *dir_mtime = l->data;
      GtkIconCache *cache = dir_mtime->cache;
      
      if (cache && _gtk_icon_cache_has_icon (cache, icon_name))
        return TRUE;
    }

  for (l = priv->themes; l; l = l->next)
    {
      if (theme_has_icon (l->data, icon_name))
        return TRUE;
    }

  if (icon_theme_builtin_icons &&
      g_hash_table_lookup_extended (icon_theme_builtin_icons,
                                    icon_name, NULL, NULL))
    return TRUE;

  return FALSE;
}

static void
add_size (gpointer key,
          gpointer value,
          gpointer user_data)
{
  gint **res_p = user_data;

  **res_p = GPOINTER_TO_INT (key);

  (*res_p)++;
}

/**
 * gtk_icon_theme_get_icon_sizes:
 * @icon_theme: a #GtkIconTheme
 * @icon_name: the name of an icon
 * 
 * Returns an array of integers describing the sizes at which
 * the icon is available without scaling. A size of -1 means 
 * that the icon is available in a scalable format. The array 
 * is zero-terminated.
 * 
 * Returns: (array zero-terminated=1) (transfer full): An newly
 * allocated array describing the sizes at which the icon is
 * available. The array should be freed with g_free() when it is no
 * longer needed.
 *
 * Since: 2.6
 */
gint *
gtk_icon_theme_get_icon_sizes (GtkIconTheme *icon_theme,
                               const gchar  *icon_name)
{
  GList *l, *d, *icons;
  GHashTable *sizes;
  gint *result, *r;
  guint suffix;  
  GtkIconThemePrivate *priv;

  g_return_val_if_fail (GTK_IS_ICON_THEME (icon_theme), NULL);
  
  priv = icon_theme->priv;

  ensure_valid_themes (icon_theme);

  sizes = g_hash_table_new (g_direct_hash, g_direct_equal);

  for (l = priv->themes; l; l = l->next)
    {
      IconTheme *theme = l->data;
      for (d = theme->dirs; d; d = d->next)
        {
          IconThemeDir *dir = d->data;

          if (dir->type != ICON_THEME_DIR_SCALABLE && g_hash_table_lookup_extended (sizes, GINT_TO_POINTER (dir->size), NULL, NULL))
            continue;

          suffix = theme_dir_get_icon_suffix (dir, icon_name, NULL);
          if (suffix != ICON_SUFFIX_NONE)
            {
              if (suffix == ICON_SUFFIX_SVG)
                g_hash_table_insert (sizes, GINT_TO_POINTER (-1), NULL);
              else
                g_hash_table_insert (sizes, GINT_TO_POINTER (dir->size), NULL);
            }
        }
    }

  if (icon_theme_builtin_icons)
    {
      icons = g_hash_table_lookup (icon_theme_builtin_icons, icon_name);
      
      while (icons)
        {
          BuiltinIcon *icon = icons->data;

          g_hash_table_insert (sizes, GINT_TO_POINTER (icon->size), NULL);
          icons = icons->next;
        }      
    }

  r = result = g_new0 (gint, g_hash_table_size (sizes) + 1);

  g_hash_table_foreach (sizes, add_size, &r);
  g_hash_table_destroy (sizes);
  
  return result;
}

static void
add_key_to_hash (gpointer key,
                 gpointer value,
                 gpointer user_data)
{
  GHashTable *hash = user_data;

  g_hash_table_insert (hash, key, NULL);
}

static void
add_key_to_list (gpointer key,
                 gpointer value,
                 gpointer user_data)
{
  GList **list = user_data;

  *list = g_list_prepend (*list, g_strdup (key));
}

/**
 * gtk_icon_theme_list_icons:
 * @icon_theme: a #GtkIconTheme
 * @context: (allow-none): a string identifying a particular type of
 *           icon, or %NULL to list all icons.
 *
 * Lists the icons in the current icon theme. Only a subset
 * of the icons can be listed by providing a context string.
 * The set of values for the context string is system dependent,
 * but will typically include such values as “Applications” and
 * “MimeTypes”. Contexts are explained in the
 * [Icon Theme Specification](http://www.freedesktop.org/wiki/Specifications/icon-theme-spec).
 * The standard contexts are listed in the
 * [Icon Naming Specification](http://www.freedesktop.org/wiki/Specifications/icon-naming-spec).
 * Also see gtk_icon_theme_list_contexts().
 *
 * Returns: (element-type utf8) (transfer full): a #GList list
 *     holding the names of all the icons in the theme. You must
 *     first free each element in the list with g_free(), then
 *     free the list itself with g_list_free().
 *
 * Since: 2.4
 */
GList *
gtk_icon_theme_list_icons (GtkIconTheme *icon_theme,
                           const gchar  *context)
{
  GtkIconThemePrivate *priv;
  GHashTable *icons;
  GList *list, *l;
  GQuark context_quark;
  
  priv = icon_theme->priv;
  
  ensure_valid_themes (icon_theme);

  if (context)
    {
      context_quark = g_quark_try_string (context);

      if (!context_quark)
        return NULL;
    }
  else
    context_quark = 0;

  icons = g_hash_table_new (g_str_hash, g_str_equal);
  
  l = priv->themes;
  while (l != NULL)
    {
      theme_list_icons (l->data, icons, context_quark);
      l = l->next;
    }

  if (context_quark == 0)
    g_hash_table_foreach (priv->unthemed_icons,
                          add_key_to_hash,
                          icons);

  list = NULL;
  
  g_hash_table_foreach (icons,
                        add_key_to_list,
                        &list);

  g_hash_table_destroy (icons);
  
  return list;
}

/**
 * gtk_icon_theme_list_contexts:
 * @icon_theme: a #GtkIconTheme
 *
 * Gets the list of contexts available within the current
 * hierarchy of icon themes.
 * See gtk_icon_theme_list_icons() for details about contexts.
 *
 * Returns: (element-type utf8) (transfer full): a #GList list
 *     holding the names of all the contexts in the theme. You must first
 *     free each element in the list with g_free(), then free the list
 *     itself with g_list_free().
 *
 * Since: 2.12
 */
GList *
gtk_icon_theme_list_contexts (GtkIconTheme *icon_theme)
{
  GtkIconThemePrivate *priv;
  GHashTable *contexts;
  GList *list, *l;

  priv = icon_theme->priv;
  
  ensure_valid_themes (icon_theme);

  contexts = g_hash_table_new (g_str_hash, g_str_equal);

  l = priv->themes;
  while (l != NULL)
    {
      theme_list_contexts (l->data, contexts);
      l = l->next;
    }

  list = NULL;

  g_hash_table_foreach (contexts,
                        add_key_to_list,
                        &list);

  g_hash_table_destroy (contexts);

  return list;
}

/**
 * gtk_icon_theme_get_example_icon_name:
 * @icon_theme: a #GtkIconTheme
 * 
 * Gets the name of an icon that is representative of the
 * current theme (for instance, to use when presenting
 * a list of themes to the user.)
 * 
 * Returns: (nullable): the name of an example icon or %NULL.
 *     Free with g_free().
 *
 * Since: 2.4
 */
gchar *
gtk_icon_theme_get_example_icon_name (GtkIconTheme *icon_theme)
{
  GtkIconThemePrivate *priv;
  GList *l;
  IconTheme *theme;

  g_return_val_if_fail (GTK_IS_ICON_THEME (icon_theme), NULL);
  
  priv = icon_theme->priv;
  
  ensure_valid_themes (icon_theme);

  l = priv->themes;
  while (l != NULL)
    {
      theme = l->data;
      if (theme->example)
        return g_strdup (theme->example);
      
      l = l->next;
    }
  
  return NULL;
}


static gboolean
rescan_themes (GtkIconTheme *icon_theme)
{
  GtkIconThemePrivate *priv;
  IconThemeDirMtime *dir_mtime;
  GList *d;
  gint stat_res;
  GStatBuf stat_buf;
  GTimeVal tv;

  priv = icon_theme->priv;

  for (d = priv->dir_mtimes; d != NULL; d = d->next)
    {
      dir_mtime = d->data;

      stat_res = g_stat (dir_mtime->dir, &stat_buf);

      /* dir mtime didn't change */
      if (stat_res == 0 && dir_mtime->exists &&
          S_ISDIR (stat_buf.st_mode) &&
          dir_mtime->mtime == stat_buf.st_mtime)
        continue;
      /* didn't exist before, and still doesn't */
      if (!dir_mtime->exists &&
          (stat_res != 0 || !S_ISDIR (stat_buf.st_mode)))
        continue;

      return TRUE;
    }

  g_get_current_time (&tv);
  priv->last_stat_time = tv.tv_sec;

  return FALSE;
}

/**
 * gtk_icon_theme_rescan_if_needed:
 * @icon_theme: a #GtkIconTheme
 * 
 * Checks to see if the icon theme has changed; if it has, any
 * currently cached information is discarded and will be reloaded
 * next time @icon_theme is accessed.
 * 
 * Returns: %TRUE if the icon theme has changed and needed
 *     to be reloaded.
 *
 * Since: 2.4
 */
gboolean
gtk_icon_theme_rescan_if_needed (GtkIconTheme *icon_theme)
{
  gboolean retval;

  g_return_val_if_fail (GTK_IS_ICON_THEME (icon_theme), FALSE);

  retval = rescan_themes (icon_theme);
  if (retval)
      do_theme_change (icon_theme);

  return retval;
}

static void
theme_destroy (IconTheme *theme)
{
  g_free (theme->display_name);
  g_free (theme->comment);
  g_free (theme->name);
  g_free (theme->example);

  g_list_free_full (theme->dirs, (GDestroyNotify) theme_dir_destroy);
  
  g_free (theme);
}

static void
theme_dir_destroy (IconThemeDir *dir)
{
  if (dir->cache)
    _gtk_icon_cache_unref (dir->cache);
  if (dir->icons)
    g_hash_table_destroy (dir->icons);
  
  g_free (dir->dir);
  g_free (dir->subdir);
  g_free (dir);
}

static int
theme_dir_size_difference (IconThemeDir *dir,
                           gint          size,
                           gint          scale)
{
  gint scaled_size, scaled_dir_size;
  gint min, max;

  scaled_size = size * scale;
  scaled_dir_size = dir->size * dir->scale;

  switch (dir->type)
    {
    case ICON_THEME_DIR_FIXED:
      return abs (scaled_size - scaled_dir_size);
      break;
    case ICON_THEME_DIR_SCALABLE:
      if (scaled_size < (dir->min_size * dir->scale))
        return (dir->min_size * dir->scale) - scaled_size;
      if (size > (dir->max_size * dir->scale))
        return scaled_size - (dir->max_size * dir->scale);
      return 0;
      break;
    case ICON_THEME_DIR_THRESHOLD:
      min = (dir->size - dir->threshold) * dir->scale;
      max = (dir->size + dir->threshold) * dir->scale;
      if (scaled_size < min)
        return min - scaled_size;
      if (scaled_size > max)
        return scaled_size - max;
      return 0;
      break;
    case ICON_THEME_DIR_UNTHEMED:
      g_assert_not_reached ();
      break;
    }
  g_assert_not_reached ();
  return 1000;
}

static const gchar *
string_from_suffix (IconSuffix suffix)
{
  switch (suffix)
    {
    case ICON_SUFFIX_XPM:
      return ".xpm";
    case ICON_SUFFIX_SVG:
      return ".svg";
    case ICON_SUFFIX_PNG:
      return ".png";
    case ICON_SUFFIX_SYMBOLIC_PNG:
      return ".symbolic.png";
    default:
      g_assert_not_reached();
    }
  return NULL;
}

static IconSuffix
suffix_from_name (const gchar *name)
{
  IconSuffix retval = ICON_SUFFIX_NONE;

  if (name != NULL)
    {
      if (g_str_has_suffix (name, ".symbolic.png"))
        retval = ICON_SUFFIX_SYMBOLIC_PNG;
      else if (g_str_has_suffix (name, ".png"))
        retval = ICON_SUFFIX_PNG;
      else if (g_str_has_suffix (name, ".svg"))
        retval = ICON_SUFFIX_SVG;
      else if (g_str_has_suffix (name, ".xpm"))
        retval = ICON_SUFFIX_XPM;
    }

  return retval;
}

static IconSuffix
best_suffix (IconSuffix suffix,
             gboolean   allow_svg)
{
  if ((suffix & ICON_SUFFIX_SYMBOLIC_PNG) != 0)
    return ICON_SUFFIX_SYMBOLIC_PNG;
  else if ((suffix & ICON_SUFFIX_PNG) != 0)
    return ICON_SUFFIX_PNG;
  else if (allow_svg && ((suffix & ICON_SUFFIX_SVG) != 0))
    return ICON_SUFFIX_SVG;
  else if ((suffix & ICON_SUFFIX_XPM) != 0)
    return ICON_SUFFIX_XPM;
  else
    return ICON_SUFFIX_NONE;
}
 
static IconSuffix
theme_dir_get_icon_suffix (IconThemeDir *dir,
                           const gchar  *icon_name,
                           gboolean     *has_icon_file)
{
  IconSuffix suffix, symbolic_suffix;

  if (dir->cache)
    {
      suffix = (IconSuffix)_gtk_icon_cache_get_icon_flags (dir->cache,
                                                           icon_name,
                                                           dir->subdir_index);

      if (icon_name_is_symbolic (icon_name))
        {
          /* Look for foo-symbolic.symbolic.png, as the cache only stores the ".png" suffix */
          char *icon_name_with_prefix = g_strconcat (icon_name, ".symbolic", NULL);
          symbolic_suffix = (IconSuffix)_gtk_icon_cache_get_icon_flags (dir->cache,
                                                                        icon_name_with_prefix,
                                                                        dir->subdir_index);
          g_free (icon_name_with_prefix);

          if (symbolic_suffix & ICON_SUFFIX_PNG)
            suffix = ICON_SUFFIX_SYMBOLIC_PNG;
        }

      if (has_icon_file)
        *has_icon_file = suffix & HAS_ICON_FILE;

      suffix = suffix & ~HAS_ICON_FILE;
    }
  else
    suffix = GPOINTER_TO_UINT (g_hash_table_lookup (dir->icons, icon_name));

  GTK_NOTE (ICONTHEME, g_message ("get icon suffix%s: %u", dir->cache ? " (cached)" : "", suffix));

  return suffix;
}

/* returns TRUE if dir_a is a better match */
static gboolean
compare_dir_matches (IconThemeDir *dir_a, gint difference_a,
                     IconThemeDir *dir_b, gint difference_b,
                     gint requested_size,
                     gint requested_scale)
{
  gint diff_a;
  gint diff_b;

  if (difference_a == 0)
    {
      if (difference_b != 0)
        return TRUE;
      
      /* a and b both exact matches */
    }
  else
    {
      /* If scaling, *always* prefer downscaling */
      if (dir_a->size >= requested_size &&
          dir_b->size < requested_size)
        return TRUE;

      if (dir_a->size < requested_size &&
          dir_b->size >= requested_size)
        return FALSE;
 
      /* Otherwise prefer the closest match */

      if (difference_a < difference_b)
        return TRUE;

      if (difference_a > difference_b)
        return FALSE;

      /* same pixel difference */
    }

  if (dir_a->scale == requested_scale &&
      dir_b->scale != requested_scale)
    return TRUE;

  if (dir_a->scale != requested_scale &&
      dir_b->scale == requested_scale)
    return FALSE;

  /* a and b both match the scale */

  if (dir_a->type != ICON_THEME_DIR_SCALABLE &&
      dir_b->type == ICON_THEME_DIR_SCALABLE)
    return TRUE;

  if (dir_a->type == ICON_THEME_DIR_SCALABLE &&
      dir_b->type != ICON_THEME_DIR_SCALABLE)
    return FALSE;
      
  /* a and b both are scalable */

  diff_a = abs (requested_size * requested_scale - dir_a->size * dir_a->scale);
  diff_b = abs (requested_size * requested_scale - dir_b->size * dir_b->scale);

  return diff_a <= diff_b;
}

static GtkIconInfo *
theme_lookup_icon (IconTheme   *theme,
                   const gchar *icon_name,
                   gint         size,
                   gint         scale,
                   gboolean     allow_svg,
                   gboolean     use_builtin)
{
  GList *dirs, *l;
  IconThemeDir *dir, *min_dir;
  gchar *file;
  gint min_difference, difference;
  BuiltinIcon *closest_builtin = NULL;
  IconSuffix suffix;

  min_difference = G_MAXINT;
  min_dir = NULL;

  /* Builtin icons are logically part of the default theme and
   * are searched before other subdirectories of the default theme.
   */
  if (use_builtin && strcmp (theme->name, FALLBACK_ICON_THEME) == 0)
    {
      closest_builtin = find_builtin_icon (icon_name, 
                                           size, scale,
                                           &min_difference);

      if (min_difference == 0)
        return icon_info_new_builtin (closest_builtin);
    }

  dirs = theme->dirs;

  l = dirs;
  while (l != NULL)
    {
      dir = l->data;

      GTK_NOTE (ICONTHEME, g_message ("look up icon dir %s", dir->dir));
      suffix = theme_dir_get_icon_suffix (dir, icon_name, NULL);
      if (best_suffix (suffix, allow_svg) != ICON_SUFFIX_NONE)
        {
          difference = theme_dir_size_difference (dir, size, scale);
          if (min_dir == NULL ||
              compare_dir_matches (dir, difference,
                                   min_dir, min_difference,
                                   size, scale))
            {
              min_dir = dir;
              min_difference = difference;
            }
        }

      l = l->next;
    }

  if (min_dir)
    {
      GtkIconInfo *icon_info;
      gboolean has_icon_file = FALSE;

      icon_info = icon_info_new (min_dir->type, min_dir->size, min_dir->scale);
      icon_info->min_size = min_dir->min_size;
      icon_info->max_size = min_dir->max_size;

      suffix = theme_dir_get_icon_suffix (min_dir, icon_name, &has_icon_file);
      suffix = best_suffix (suffix, allow_svg);
      g_assert (suffix != ICON_SUFFIX_NONE);

      if (min_dir->dir)
        {
          file = g_strconcat (icon_name, string_from_suffix (suffix), NULL);
          icon_info->filename = g_build_filename (min_dir->dir, file, NULL);

          if (min_dir->is_resource)
            {
              gchar *uri;
              uri = g_strconcat ("resource://", icon_info->filename, NULL);
              icon_info->icon_file = g_file_new_for_uri (uri);
              g_free (uri);
            }
          else
            icon_info->icon_file = g_file_new_for_path (icon_info->filename);

          icon_info->is_svg = suffix == ICON_SUFFIX_SVG;
          icon_info->is_resource = min_dir->is_resource;
          g_free (file);
        }
      else
        {
          icon_info->filename = NULL;
          icon_info->icon_file = NULL;
        }

      if (min_dir->cache)
        {
          icon_info->cache_pixbuf = _gtk_icon_cache_get_icon (min_dir->cache, icon_name,
                                                              min_dir->subdir_index);
        }

      return icon_info;
    }

  if (closest_builtin)
    return icon_info_new_builtin (closest_builtin);
  
  return NULL;
}

static void
theme_list_icons (IconTheme  *theme, 
                  GHashTable *icons,
                  GQuark      context)
{
  GList *l = theme->dirs;
  IconThemeDir *dir;
  
  while (l != NULL)
    {
      dir = l->data;

      if (context == dir->context ||
          context == 0)
        {
          if (dir->cache)
            _gtk_icon_cache_add_icons (dir->cache, dir->subdir, icons);
          else
            g_hash_table_foreach (dir->icons, add_key_to_hash, icons);
        }
      l = l->next;
    }
}

static gboolean
theme_has_icon (IconTheme   *theme,
                const gchar *icon_name)
{
  GList *l;

  for (l = theme->dirs; l; l = l->next)
    {
      IconThemeDir *dir = l->data;

      if (dir->cache)
        {
          if (_gtk_icon_cache_has_icon (dir->cache, icon_name))
            return TRUE;
        }
      else
        {
          if (g_hash_table_lookup (dir->icons, icon_name) != NULL)
            return TRUE;
        }
    }

  return FALSE;
}

static void
theme_list_contexts (IconTheme  *theme, 
                     GHashTable *contexts)
{
  GList *l = theme->dirs;
  IconThemeDir *dir;
  const gchar *context;

  while (l != NULL)
    {
      dir = l->data;

      context = g_quark_to_string (dir->context);
      if (context != NULL)
        g_hash_table_replace (contexts, (gpointer) context, NULL);

      l = l->next;
    }
}

static gboolean
scan_directory (GtkIconThemePrivate *icon_theme,
                IconThemeDir        *dir,
                gchar               *full_dir)
{
  GDir *gdir;
  const gchar *name;

  GTK_NOTE (ICONTHEME, g_message ("scanning directory %s", full_dir));

  gdir = g_dir_open (full_dir, 0, NULL);

  if (gdir == NULL)
    return FALSE;

  dir->icons = g_hash_table_new_full (g_str_hash, g_str_equal, g_free, NULL);

  while ((name = g_dir_read_name (gdir)))
    {
      gchar *base_name;
      IconSuffix suffix, hash_suffix;

      suffix = suffix_from_name (name);
      if (suffix == ICON_SUFFIX_NONE)
        continue;

      base_name = strip_suffix (name);

      hash_suffix = GPOINTER_TO_INT (g_hash_table_lookup (dir->icons, base_name));
      /* takes ownership of base_name */
      g_hash_table_replace (dir->icons, base_name, GUINT_TO_POINTER (hash_suffix|suffix));
    }
  
  g_dir_close (gdir);

  return g_hash_table_size (dir->icons) > 0;
}

static gboolean
scan_resources (GtkIconThemePrivate  *icon_theme,
                IconThemeDir         *dir,
                gchar                *full_dir)
{
  gint i;
  gchar **children;

  GTK_NOTE (ICONTHEME, g_message ("scanning resources %s", full_dir));

  children = g_resources_enumerate_children (full_dir, 0, NULL);
  if (!children)
    return FALSE;

  dir->icons = g_hash_table_new_full (g_str_hash, g_str_equal, g_free, NULL);

  for (i = 0; children[i]; i++)
    {
      gchar *base_name;
      IconSuffix suffix, hash_suffix;

      suffix = suffix_from_name (children[i]);
      if (suffix == ICON_SUFFIX_NONE)
        continue;

      base_name = strip_suffix (children[i]);

      hash_suffix = GPOINTER_TO_INT (g_hash_table_lookup (dir->icons, base_name));
      /* takes ownership of base_name */
      g_hash_table_replace (dir->icons, base_name, GUINT_TO_POINTER (hash_suffix|suffix));
    }
  g_strfreev (children);

  return g_hash_table_size (dir->icons) > 0;
}

static void
theme_subdir_load (GtkIconTheme *icon_theme,
                   IconTheme    *theme,
                   GKeyFile     *theme_file,
                   gchar        *subdir)
{
  GList *d;
  gchar *type_string;
  IconThemeDir *dir;
  IconThemeDirType type;
  gchar *context_string;
  GQuark context;
  gint size;
  gint min_size;
  gint max_size;
  gint threshold;
  gchar *full_dir;
  GError *error = NULL;
  IconThemeDirMtime *dir_mtime;
  gint scale;
  gboolean has_icons;

  size = g_key_file_get_integer (theme_file, subdir, "Size", &error);
  if (error)
    {
      g_error_free (error);
      g_warning ("Theme directory %s of theme %s has no size field\n", 
                 subdir, theme->name);
      return;
    }
  
  type = ICON_THEME_DIR_THRESHOLD;
  type_string = g_key_file_get_string (theme_file, subdir, "Type", NULL);
  if (type_string)
    {
      if (strcmp (type_string, "Fixed") == 0)
        type = ICON_THEME_DIR_FIXED;
      else if (strcmp (type_string, "Scalable") == 0)
        type = ICON_THEME_DIR_SCALABLE;
      else if (strcmp (type_string, "Threshold") == 0)
        type = ICON_THEME_DIR_THRESHOLD;

      g_free (type_string);
    }
  
  context = 0;
  context_string = g_key_file_get_string (theme_file, subdir, "Context", NULL);
  if (context_string)
    {
      context = g_quark_from_string (context_string);
      g_free (context_string);
    }

  if (g_key_file_has_key (theme_file, subdir, "MaxSize", NULL))
    max_size = g_key_file_get_integer (theme_file, subdir, "MaxSize", NULL);
  else
    max_size = size;

  if (g_key_file_has_key (theme_file, subdir, "MinSize", NULL))
    min_size = g_key_file_get_integer (theme_file, subdir, "MinSize", NULL);
  else
    min_size = size;

  if (g_key_file_has_key (theme_file, subdir, "Threshold", NULL))
    threshold = g_key_file_get_integer (theme_file, subdir, "Threshold", NULL);
  else
    threshold = 2;

  if (g_key_file_has_key (theme_file, subdir, "Scale", NULL))
    scale = g_key_file_get_integer (theme_file, subdir, "Scale", NULL);
  else
    scale = 1;

  for (d = icon_theme->priv->dir_mtimes; d; d = d->next)
    {
      dir_mtime = (IconThemeDirMtime *)d->data;

      if (!dir_mtime->exists)
        continue; /* directory doesn't exist */

      full_dir = g_build_filename (dir_mtime->dir, subdir, NULL);

      /* First, see if we have a cache for the directory */
      if (dir_mtime->cache != NULL || g_file_test (full_dir, G_FILE_TEST_IS_DIR))
        {
          if (dir_mtime->cache == NULL)
            {
              /* This will return NULL if the cache doesn't exist or is outdated */
              dir_mtime->cache = _gtk_icon_cache_new_for_path (dir_mtime->dir);
            }

          dir = g_new0 (IconThemeDir, 1);
          dir->type = type;
          dir->is_resource = FALSE;
          dir->context = context;
          dir->size = size;
          dir->min_size = min_size;
          dir->max_size = max_size;
          dir->threshold = threshold;
          dir->dir = full_dir;
          dir->subdir = g_strdup (subdir);
          dir->scale = scale;

          if (dir_mtime->cache != NULL)
            {
              dir->cache = _gtk_icon_cache_ref (dir_mtime->cache);
              dir->subdir_index = _gtk_icon_cache_get_directory_index (dir->cache, dir->subdir);
              has_icons = _gtk_icon_cache_has_icons (dir->cache, dir->subdir);
            }
          else
            {
              dir->cache = NULL;
              dir->subdir_index = -1;
              has_icons = scan_directory (icon_theme->priv, dir, full_dir);
            }

          if (has_icons)
            theme->dirs = g_list_prepend (theme->dirs, dir);
          else
            theme_dir_destroy (dir);
        }
      else
        g_free (full_dir);
    }

  if (strcmp (theme->name, FALLBACK_ICON_THEME) == 0)
    { 
      for (d = icon_theme->priv->resource_paths; d; d = d->next)
        {
          full_dir = g_build_filename ((const gchar *)d->data, subdir, NULL);
          dir = g_new0 (IconThemeDir, 1);
          dir->type = type;
          dir->is_resource = TRUE;
          dir->context = context;
          dir->size = size;
          dir->min_size = min_size;
          dir->max_size = max_size;
          dir->threshold = threshold;
          dir->dir = full_dir;
          dir->subdir = g_strdup (subdir);
          dir->scale = scale;
          dir->cache = NULL;
          dir->subdir_index = -1;

          if (scan_resources (icon_theme->priv, dir, full_dir))
            theme->dirs = g_list_prepend (theme->dirs, dir);
          else
            theme_dir_destroy (dir);
        }
    }
}

/*
 * GtkIconInfo
 */

G_DEFINE_TYPE (GtkIconInfo, gtk_icon_info, G_TYPE_OBJECT)

static void
gtk_icon_info_init (GtkIconInfo *icon_info)
{
  icon_info->scale = -1.;
}

static GtkIconInfo *
icon_info_new (IconThemeDirType type,
               gint             dir_size,
               gint             dir_scale)
{
  GtkIconInfo *icon_info;

  icon_info = g_object_new (GTK_TYPE_ICON_INFO, NULL);

  icon_info->dir_type = type;
  icon_info->dir_size = dir_size;
  icon_info->dir_scale = dir_scale;
  icon_info->unscaled_scale = 1.0;
  icon_info->is_svg = FALSE;
  icon_info->is_resource = FALSE;

  return icon_info;
}

/* This only copies whatever is needed to load the pixbuf,
 * so that we can do a load in a thread without affecting
 * the original IconInfo from the thread.
 */
static GtkIconInfo *
icon_info_dup (GtkIconInfo *icon_info)
{
  GtkIconInfo *dup;
  GSList *l;

  dup = icon_info_new (icon_info->dir_type, icon_info->dir_size, icon_info->dir_scale);

  dup->filename = g_strdup (icon_info->filename);
  dup->is_svg = icon_info->is_svg;

  if (icon_info->icon_file)
    dup->icon_file = g_object_ref (icon_info->icon_file);
  if (icon_info->loadable)
    dup->loadable = g_object_ref (icon_info->loadable);
  if (icon_info->pixbuf)
    dup->pixbuf = g_object_ref (icon_info->pixbuf);

  for (l = icon_info->emblem_infos; l != NULL; l = l->next)
    {
      dup->emblem_infos =
        g_slist_append (dup->emblem_infos,
                        icon_info_dup (l->data));
    }

  if (icon_info->cache_pixbuf)
    dup->cache_pixbuf = g_object_ref (icon_info->cache_pixbuf);

  dup->scale = icon_info->scale;
  dup->unscaled_scale = icon_info->unscaled_scale;
  dup->desired_size = icon_info->desired_size;
  dup->desired_scale = icon_info->desired_scale;
  dup->forced_size = icon_info->forced_size;
  dup->emblems_applied = icon_info->emblems_applied;
  dup->is_resource = icon_info->is_resource;
  dup->min_size = icon_info->min_size;
  dup->max_size = icon_info->max_size;
  dup->symbolic_width = icon_info->symbolic_width;
  dup->symbolic_height = icon_info->symbolic_height;

  return dup;
}

static GtkIconInfo *
icon_info_new_builtin (BuiltinIcon *icon)
{
  GtkIconInfo *icon_info = icon_info_new (ICON_THEME_DIR_THRESHOLD, icon->size, 1);

  icon_info->cache_pixbuf = g_object_ref (icon->pixbuf);

  return icon_info;
}

static void
gtk_icon_info_finalize (GObject *object)
{
  GtkIconInfo *icon_info = (GtkIconInfo *) object;

  if (icon_info->in_cache)
    g_hash_table_remove (icon_info->in_cache->priv->info_cache, &icon_info->key);

  g_strfreev (icon_info->key.icon_names);

  g_free (icon_info->filename);
  g_clear_object (&icon_info->icon_file);

  g_clear_object (&icon_info->loadable);
  g_slist_free_full (icon_info->emblem_infos, (GDestroyNotify) g_object_unref);
  g_clear_object (&icon_info->pixbuf);
  g_clear_object (&icon_info->proxy_pixbuf);
  g_clear_object (&icon_info->cache_pixbuf);
  g_clear_error (&icon_info->load_error);

  symbolic_pixbuf_cache_free (icon_info->symbolic_pixbuf_cache);

  G_OBJECT_CLASS (gtk_icon_info_parent_class)->finalize (object);
}

static void
gtk_icon_info_class_init (GtkIconInfoClass *klass)
{
  GObjectClass *gobject_class = G_OBJECT_CLASS (klass);

  gobject_class->finalize = gtk_icon_info_finalize;
}

/**
 * gtk_icon_info_get_base_size:
 * @icon_info: a #GtkIconInfo
 * 
 * Gets the base size for the icon. The base size
 * is a size for the icon that was specified by
 * the icon theme creator. This may be different
 * than the actual size of image; an example of
 * this is small emblem icons that can be attached
 * to a larger icon. These icons will be given
 * the same base size as the larger icons to which
 * they are attached.
 *
 * Note that for scaled icons the base size does
 * not include the base scale.
 *
 * Returns: the base size, or 0, if no base
 *     size is known for the icon.
 *
 * Since: 2.4
 */
gint
gtk_icon_info_get_base_size (GtkIconInfo *icon_info)
{
  g_return_val_if_fail (icon_info != NULL, 0);

  return icon_info->dir_size;
}

/**
 * gtk_icon_info_get_base_scale:
 * @icon_info: a #GtkIconInfo
 *
 * Gets the base scale for the icon. The base scale is a scale
 * for the icon that was specified by the icon theme creator.
 * For instance an icon drawn for a high-dpi screen with window
 * scale 2 for a base size of 32 will be 64 pixels tall and have
 * a base scale of 2.
 *
 * Returns: the base scale
 *
 * Since: 3.10
 */
gint
gtk_icon_info_get_base_scale (GtkIconInfo *icon_info)
{
  g_return_val_if_fail (icon_info != NULL, 0);

  return icon_info->dir_scale;
}

/**
 * gtk_icon_info_get_filename:
 * @icon_info: a #GtkIconInfo
 * 
 * Gets the filename for the icon. If the %GTK_ICON_LOOKUP_USE_BUILTIN
 * flag was passed to gtk_icon_theme_lookup_icon(), there may be no
 * filename if a builtin icon is returned; in this case, you should
 * use gtk_icon_info_get_builtin_pixbuf().
 * 
 * Returns: (nullable) (type filename): the filename for the icon, or %NULL
 *     if gtk_icon_info_get_builtin_pixbuf() should be used instead.
 *     The return value is owned by GTK+ and should not be modified
 *     or freed.
 *
 * Since: 2.4
 */
const gchar *
gtk_icon_info_get_filename (GtkIconInfo *icon_info)
{
  g_return_val_if_fail (icon_info != NULL, NULL);

  return icon_info->filename;
}

/**
 * gtk_icon_info_is_symbolic:
 * @icon_info: a #GtkIconInfo
 *
 * Checks if the icon is symbolic or not. This currently uses only
 * the file name and not the file contents for determining this.
 * This behaviour may change in the future.
 *
 * Returns: %TRUE if the icon is symbolic, %FALSE otherwise
 *
 * Since: 3.12
 */
gboolean
gtk_icon_info_is_symbolic (GtkIconInfo *icon_info)
{
  gchar *icon_uri;
  gboolean is_symbolic;

  g_return_val_if_fail (GTK_IS_ICON_INFO (icon_info), FALSE);

  icon_uri = NULL;
  if (icon_info->icon_file)
    icon_uri = g_file_get_uri (icon_info->icon_file);

  is_symbolic = (icon_uri != NULL) && (icon_uri_is_symbolic (icon_uri));
  g_free (icon_uri);

  return is_symbolic;
}

static GdkPixbuf *
apply_emblems_to_pixbuf (GdkPixbuf   *pixbuf,
                         GtkIconInfo *info)
{
  GdkPixbuf *icon = NULL;
  gint w, h, pos;
  GSList *l;

  if (info->emblem_infos == NULL)
    return NULL;

  w = gdk_pixbuf_get_width (pixbuf);
  h = gdk_pixbuf_get_height (pixbuf);

  for (l = info->emblem_infos, pos = 0; l; l = l->next, pos++)
    {
      GtkIconInfo *emblem_info = l->data;

      if (icon_info_ensure_scale_and_pixbuf (emblem_info))
        {
          GdkPixbuf *emblem = emblem_info->pixbuf;
          gint ew, eh;
          gint x = 0, y = 0; /* silence compiler */
          gdouble scale;

          ew = gdk_pixbuf_get_width (emblem);
          eh = gdk_pixbuf_get_height (emblem);
          if (ew >= w)
            {
              scale = 0.75;
              ew = ew * 0.75;
              eh = eh * 0.75;
            }
          else
            scale = 1.0;

          switch (pos % 4)
            {
            case 0:
              x = w - ew;
              y = h - eh;
              break;
            case 1:
              x = w - ew;
              y = 0;
              break;
            case 2:
              x = 0;
              y = h - eh;
              break;
            case 3:
              x = 0;
              y = 0;
              break;
            }

          if (icon == NULL)
            {
              icon = gdk_pixbuf_copy (pixbuf);
              if (icon == NULL)
                break;
            }

          gdk_pixbuf_composite (emblem, icon, x, y, ew, eh, x, y,
                                scale, scale, GDK_INTERP_BILINEAR, 255);
       }
   }

  return icon;
}

/* Combine the icon with all emblems, the first emblem is placed 
 * in the southeast corner. Scale emblems to be at most 3/4 of the
 * size of the icon itself.
 */
static void 
apply_emblems (GtkIconInfo *info)
{
  GdkPixbuf *icon;

  if (info->emblems_applied)
    return;

  icon = apply_emblems_to_pixbuf (info->pixbuf, info);

  if (icon)
    {
      g_object_unref (info->pixbuf);
      info->pixbuf = icon;
      info->emblems_applied = TRUE;
    }
}

/* If this returns TRUE, its safe to call icon_info_ensure_scale_and_pixbuf
 * without blocking
 */
static gboolean
icon_info_get_pixbuf_ready (GtkIconInfo *icon_info)
{
  if (icon_info->pixbuf &&
      (icon_info->emblem_infos == NULL || icon_info->emblems_applied))
    return TRUE;

  if (icon_info->load_error)
    return TRUE;

  return FALSE;
}

/* This function contains the complicated logic for deciding
 * on the size at which to load the icon and loading it at
 * that size.
 */
static gboolean
icon_info_ensure_scale_and_pixbuf (GtkIconInfo *icon_info)
{
  gint image_width, image_height, image_size;
  gint scaled_desired_size;
  GdkPixbuf *source_pixbuf;
  gdouble dir_scale;

  if (icon_info->pixbuf)
    {
      apply_emblems (icon_info);
      return TRUE;
    }

  if (icon_info->load_error)
    return FALSE;

  if (icon_info->icon_file && !icon_info->loadable)
    icon_info->loadable = G_LOADABLE_ICON (g_file_icon_new (icon_info->icon_file));

  scaled_desired_size = icon_info->desired_size * icon_info->desired_scale;

  dir_scale = icon_info->dir_scale;

  /* In many cases, the scale can be determined without actual access
   * to the icon file. This is generally true when we have a size
   * for the directory where the icon is; the image size doesn't
   * matter in that case.
   */
  if (icon_info->forced_size ||
      icon_info->dir_type == ICON_THEME_DIR_UNTHEMED)
    icon_info->scale = -1;
  else if (icon_info->dir_type == ICON_THEME_DIR_FIXED ||
           icon_info->dir_type == ICON_THEME_DIR_THRESHOLD)
    icon_info->scale = icon_info->unscaled_scale;
  else if (icon_info->dir_type == ICON_THEME_DIR_SCALABLE)
    {
      /* For svg icons, treat scalable directories as if they had
       * a Scale=<desired_scale> entry. In particular, this means
       * spinners that are restriced to size 32 will loaded at size
       * up to 64 with Scale=2.
       */
      if (icon_info->is_svg)
        dir_scale = icon_info->desired_scale;

      if (scaled_desired_size < icon_info->min_size * dir_scale)
        icon_info->scale = (gdouble) icon_info->min_size / (gdouble) icon_info->dir_size;
      else if (scaled_desired_size > icon_info->max_size * dir_scale)
        icon_info->scale = (gdouble) icon_info->max_size / (gdouble) icon_info->dir_size;
      else
        icon_info->scale = (gdouble) scaled_desired_size / (icon_info->dir_size * dir_scale);
    }

  /* At this point, we need to actually get the icon; either from the
   * builtin image or by loading the file
   */
  source_pixbuf = NULL;
  if (icon_info->cache_pixbuf)
    source_pixbuf = g_object_ref (icon_info->cache_pixbuf);
  else if (icon_info->is_resource)
    {
      if (icon_info->is_svg)
        {
          gint size;

          if (icon_info->forced_size || icon_info->dir_type == ICON_THEME_DIR_UNTHEMED)
            size = scaled_desired_size;
          else
            size = icon_info->dir_size * dir_scale * icon_info->scale;

          if (size == 0)
            source_pixbuf = _gdk_pixbuf_new_from_resource_scaled (icon_info->filename,
                                                                  icon_info->desired_scale,
                                                                  &icon_info->load_error);
          else
            source_pixbuf = gdk_pixbuf_new_from_resource_at_scale (icon_info->filename,
                                                                   size, size, TRUE,
                                                                   &icon_info->load_error);
        }
      else
        source_pixbuf = gdk_pixbuf_new_from_resource (icon_info->filename,
                                                      &icon_info->load_error);
    }
  else
    {
      GInputStream *stream;

      /* TODO: We should have a load_at_scale */
      stream = g_loadable_icon_load (icon_info->loadable,
                                     scaled_desired_size,
                                     NULL, NULL,
                                     &icon_info->load_error);
      if (stream)
        {
          /* SVG icons are a special case - we just immediately scale them
           * to the desired size
           */
          if (icon_info->is_svg)
            {
              gint size;

              if (icon_info->forced_size || icon_info->dir_type == ICON_THEME_DIR_UNTHEMED)
                size = scaled_desired_size;
              else
                size = icon_info->dir_size * dir_scale * icon_info->scale;
              if (size == 0)
                source_pixbuf = _gdk_pixbuf_new_from_stream_scaled (stream,
                                                                    icon_info->desired_scale,
                                                                    NULL,
                                                                    &icon_info->load_error);
              else
                source_pixbuf = gdk_pixbuf_new_from_stream_at_scale (stream,
                                                                     size, size,
                                                                     TRUE, NULL,
                                                                     &icon_info->load_error);
            }
          else
            source_pixbuf = gdk_pixbuf_new_from_stream (stream,
                                                        NULL,
                                                        &icon_info->load_error);
          g_object_unref (stream);
        }
    }

  if (!source_pixbuf)
    {
      static gboolean warn_about_load_failure = TRUE;

      if (warn_about_load_failure)
        {
          gchar *path;

          if (icon_info->is_resource)
            path = g_strdup (icon_info->filename);
          else if (G_IS_FILE (icon_info->loadable))
            path = g_file_get_path (G_FILE (icon_info->loadable));
          else
            path = g_strdup ("icon theme");

          g_warning ("Could not load a pixbuf from %s.\n"
                     "This may indicate that pixbuf loaders or the mime database could not be found.",
                     path);
          g_free (path);

          warn_about_load_failure = FALSE;
        }

      return FALSE;
    }

  /* Do scale calculations that depend on the image size
   */
  image_width = gdk_pixbuf_get_width (source_pixbuf);
  image_height = gdk_pixbuf_get_height (source_pixbuf);
  image_size = MAX (image_width, image_height);

  if (icon_info->is_svg)
    icon_info->scale = image_size / 1000.;
  else if (icon_info->scale < 0.0)
    {
      if (image_size > 0 && scaled_desired_size > 0)
        icon_info->scale = (gdouble)scaled_desired_size / (gdouble)image_size;
      else
        icon_info->scale = 1.0;
      
      if (icon_info->dir_type == ICON_THEME_DIR_UNTHEMED && 
          !icon_info->forced_size)
        icon_info->scale = MIN (icon_info->scale, 1.0);
    }

  if (icon_info->is_svg)
    icon_info->pixbuf = source_pixbuf;
  else if (icon_info->scale == 1.0)
    icon_info->pixbuf = source_pixbuf;
  else
    {
      icon_info->pixbuf = gdk_pixbuf_scale_simple (source_pixbuf,
                                                   0.5 + image_width * icon_info->scale,
                                                   0.5 + image_height * icon_info->scale,
                                                   GDK_INTERP_BILINEAR);
      g_object_unref (source_pixbuf);
    }

  apply_emblems (icon_info);

  return TRUE;
}

static void
proxy_pixbuf_destroy (guchar *pixels, gpointer data)
{
  GtkIconInfo *icon_info = data;
  GtkIconTheme *icon_theme = icon_info->in_cache;

  g_assert (icon_info->proxy_pixbuf != NULL);
  icon_info->proxy_pixbuf = NULL;

  /* Keep it alive a bit longer */
  if (icon_theme != NULL)
    ensure_in_lru_cache (icon_theme, icon_info);

  g_object_unref (icon_info);
}

/**
 * gtk_icon_info_load_icon:
 * @icon_info: a #GtkIconInfo from gtk_icon_theme_lookup_icon()
 * @error: (allow-none): location to store error information on failure,
 *     or %NULL.
 *
 * Renders an icon previously looked up in an icon theme using
 * gtk_icon_theme_lookup_icon(); the size will be based on the size
 * passed to gtk_icon_theme_lookup_icon(). Note that the resulting
 * pixbuf may not be exactly this size; an icon theme may have icons
 * that differ slightly from their nominal sizes, and in addition GTK+
 * will avoid scaling icons that it considers sufficiently close to the
 * requested size or for which the source image would have to be scaled
 * up too far. (This maintains sharpness.). This behaviour can be changed
 * by passing the %GTK_ICON_LOOKUP_FORCE_SIZE flag when obtaining
 * the #GtkIconInfo. If this flag has been specified, the pixbuf
 * returned by this function will be scaled to the exact size.
 *
 * Returns: (transfer full): the rendered icon; this may be a newly
 *     created icon or a new reference to an internal icon, so you must
 *     not modify the icon. Use g_object_unref() to release your reference
 *     to the icon.
 *
 * Since: 2.4
 */
GdkPixbuf *
gtk_icon_info_load_icon (GtkIconInfo *icon_info,
                         GError     **error)
{
  g_return_val_if_fail (icon_info != NULL, NULL);
  g_return_val_if_fail (error == NULL || *error == NULL, NULL);

  if (!icon_info_ensure_scale_and_pixbuf (icon_info))
    {
      if (icon_info->load_error)
        {
          if (error)
            *error = g_error_copy (icon_info->load_error);
        }
      else
        {
          g_set_error_literal (error,  
                               GTK_ICON_THEME_ERROR,  
                               GTK_ICON_THEME_NOT_FOUND,
                               _("Failed to load icon"));
        }
 
      return NULL;
    }

  /* Instead of returning the pixbuf directly we return a proxy
   * to it that we don't own (but that shares the data with the
   * one we own). This way we can know when it is freed and ensure
   * the IconInfo is alive (and thus cached) while the pixbuf is
   * still alive.
   */
  if (icon_info->proxy_pixbuf != NULL)
    return g_object_ref (icon_info->proxy_pixbuf);

  icon_info->proxy_pixbuf =
    gdk_pixbuf_new_from_data (gdk_pixbuf_get_pixels (icon_info->pixbuf),
                              gdk_pixbuf_get_colorspace (icon_info->pixbuf),
                              gdk_pixbuf_get_has_alpha (icon_info->pixbuf),
                              gdk_pixbuf_get_bits_per_sample (icon_info->pixbuf),
                              gdk_pixbuf_get_width (icon_info->pixbuf),
                              gdk_pixbuf_get_height (icon_info->pixbuf),
                              gdk_pixbuf_get_rowstride (icon_info->pixbuf),
                              proxy_pixbuf_destroy,
                              g_object_ref (icon_info));

  return icon_info->proxy_pixbuf;
}

/**
 * gtk_icon_info_load_surface:
 * @icon_info: a #GtkIconInfo from gtk_icon_theme_lookup_icon()
 * @for_window: (allow-none): #GdkWindow to optimize drawing for, or %NULL
 * @error: (allow-none): location for error information on failure, or %NULL
 *
 * Renders an icon previously looked up in an icon theme using
 * gtk_icon_theme_lookup_icon(); the size will be based on the size
 * passed to gtk_icon_theme_lookup_icon(). Note that the resulting
 * surface may not be exactly this size; an icon theme may have icons
 * that differ slightly from their nominal sizes, and in addition GTK+
 * will avoid scaling icons that it considers sufficiently close to the
 * requested size or for which the source image would have to be scaled
 * up too far. (This maintains sharpness.). This behaviour can be changed
 * by passing the %GTK_ICON_LOOKUP_FORCE_SIZE flag when obtaining
 * the #GtkIconInfo. If this flag has been specified, the pixbuf
 * returned by this function will be scaled to the exact size.
 *
 * Returns: (transfer full): the rendered icon; this may be a newly
 *     created icon or a new reference to an internal icon, so you must
 *     not modify the icon. Use cairo_surface_destroy() to release your
 *     reference to the icon.
 *
 * Since: 3.10
 */
cairo_surface_t *
gtk_icon_info_load_surface (GtkIconInfo  *icon_info,
                            GdkWindow    *for_window,
                            GError      **error)
{
  GdkPixbuf *pixbuf;
  cairo_surface_t *surface;

  g_return_val_if_fail (icon_info != NULL, NULL);
  g_return_val_if_fail (error == NULL || *error == NULL, NULL);

  pixbuf = gtk_icon_info_load_icon (icon_info, error);

  if (pixbuf == NULL)
    return NULL;

  surface = gdk_cairo_surface_create_from_pixbuf (pixbuf, icon_info->desired_scale, for_window);
  g_object_unref (pixbuf);

  return surface;
}

static void
load_icon_thread  (GTask        *task,
                   gpointer      source_object,
                   gpointer      task_data,
                   GCancellable *cancellable)
{
  GtkIconInfo *dup = task_data;

  (void)icon_info_ensure_scale_and_pixbuf (dup);
  g_task_return_pointer (task, NULL, NULL);
}

/**
 * gtk_icon_info_load_icon_async:
 * @icon_info: a #GtkIconInfo from gtk_icon_theme_lookup_icon()
 * @cancellable: (allow-none): optional #GCancellable object, %NULL to ignore
 * @callback: (scope async): a #GAsyncReadyCallback to call when the
 *     request is satisfied
 * @user_data: (closure): the data to pass to callback function
 *
 * Asynchronously load, render and scale an icon previously looked up
 * from the icon theme using gtk_icon_theme_lookup_icon().
 *
 * For more details, see gtk_icon_info_load_icon() which is the synchronous
 * version of this call.
 *
 * Since: 3.8
 */
void
gtk_icon_info_load_icon_async (GtkIconInfo         *icon_info,
                               GCancellable        *cancellable,
                               GAsyncReadyCallback  callback,
                               gpointer             user_data)
{
  GTask *task;
  GdkPixbuf *pixbuf;
  GtkIconInfo *dup;
  GError *error = NULL;

  task = g_task_new (icon_info, cancellable, callback, user_data);

  if (icon_info_get_pixbuf_ready (icon_info))
    {
      pixbuf = gtk_icon_info_load_icon (icon_info, &error);
      if (pixbuf == NULL)
        g_task_return_error (task, error);
      else
        g_task_return_pointer (task, pixbuf, g_object_unref);
      g_object_unref (task);
    }
  else
    {
      dup = icon_info_dup (icon_info);
      g_task_set_task_data (task, dup, g_object_unref);
      g_task_run_in_thread (task, load_icon_thread);
      g_object_unref (task);
    }
}

/**
 * gtk_icon_info_load_icon_finish:
 * @icon_info: a #GtkIconInfo from gtk_icon_theme_lookup_icon()
 * @res: a #GAsyncResult
 * @error: (allow-none): location to store error information on failure,
 *     or %NULL.
 *
 * Finishes an async icon load, see gtk_icon_info_load_icon_async().
 *
 * Returns: (transfer full): the rendered icon; this may be a newly
 *     created icon or a new reference to an internal icon, so you must
 *     not modify the icon. Use g_object_unref() to release your reference
 *     to the icon.
 *
 * Since: 3.8
 */
GdkPixbuf *
gtk_icon_info_load_icon_finish (GtkIconInfo   *icon_info,
                                GAsyncResult  *result,
                                GError       **error)
{
  GTask *task = G_TASK (result);
  GtkIconInfo *dup;

  g_return_val_if_fail (g_task_is_valid (result, icon_info), NULL);

  dup = g_task_get_task_data (task);
  if (dup == NULL || g_task_had_error (task))
    return g_task_propagate_pointer (task, error);

  /* We ran the thread and it was not cancelled */

  /* Check if someone else updated the icon_info in between */
  if (!icon_info_get_pixbuf_ready (icon_info))
    {
      /* If not, copy results from dup back to icon_info */
      icon_info->emblems_applied = dup->emblems_applied;
      icon_info->scale = dup->scale;
      g_clear_object (&icon_info->pixbuf);
      if (dup->pixbuf)
        icon_info->pixbuf = g_object_ref (dup->pixbuf);
      g_clear_error (&icon_info->load_error);
      if (dup->load_error)
        icon_info->load_error = g_error_copy (dup->load_error);
    }

  g_assert (icon_info_get_pixbuf_ready (icon_info));

  /* This is now guaranteed to not block */
  return gtk_icon_info_load_icon (icon_info, error);
}

static void
proxy_symbolic_pixbuf_destroy (guchar   *pixels,
                               gpointer  data)
{
  GtkIconInfo *icon_info = data;
  GtkIconTheme *icon_theme = icon_info->in_cache;
  SymbolicPixbufCache *symbolic_cache;

  for (symbolic_cache = icon_info->symbolic_pixbuf_cache;
       symbolic_cache != NULL;
       symbolic_cache = symbolic_cache->next)
    {
      if (symbolic_cache->proxy_pixbuf != NULL &&
          gdk_pixbuf_get_pixels (symbolic_cache->proxy_pixbuf) == pixels)
        break;
    }

  g_assert (symbolic_cache != NULL);
  g_assert (symbolic_cache->proxy_pixbuf != NULL);

  symbolic_cache->proxy_pixbuf = NULL;

  /* Keep it alive a bit longer */
  if (icon_theme != NULL)
    ensure_in_lru_cache (icon_theme, icon_info);

  g_object_unref (icon_info);
}

static GdkPixbuf *
symbolic_cache_get_proxy (SymbolicPixbufCache *symbolic_cache,
                          GtkIconInfo         *icon_info)
{
  if (symbolic_cache->proxy_pixbuf)
    return g_object_ref (symbolic_cache->proxy_pixbuf);

  symbolic_cache->proxy_pixbuf =
    gdk_pixbuf_new_from_data (gdk_pixbuf_get_pixels (symbolic_cache->pixbuf),
                              gdk_pixbuf_get_colorspace (symbolic_cache->pixbuf),
                              gdk_pixbuf_get_has_alpha (symbolic_cache->pixbuf),
                              gdk_pixbuf_get_bits_per_sample (symbolic_cache->pixbuf),
                              gdk_pixbuf_get_width (symbolic_cache->pixbuf),
                              gdk_pixbuf_get_height (symbolic_cache->pixbuf),
                              gdk_pixbuf_get_rowstride (symbolic_cache->pixbuf),
                              proxy_symbolic_pixbuf_destroy,
                              g_object_ref (icon_info));

  return symbolic_cache->proxy_pixbuf;
}

static gchar *
rgba_to_string_noalpha (const GdkRGBA *rgba)
{
  GdkRGBA color;

  color = *rgba;
  color.alpha = 1.0;

  return gdk_rgba_to_string (&color);
}

static void
rgba_to_pixel(const GdkRGBA  *rgba,
	      guint8 pixel[4])
{
  pixel[0] = rgba->red * 255;
  pixel[1] = rgba->green * 255;
  pixel[2] = rgba->blue * 255;
  pixel[3] = 255;
}

GdkPixbuf *
gtk_icon_theme_color_symbolic_pixbuf (GdkPixbuf     *symbolic,
                                      const GdkRGBA *fg_color,
                                      const GdkRGBA *success_color,
                                      const GdkRGBA *warning_color,
                                      const GdkRGBA *error_color)
{
  int width, height, x, y, src_stride, dst_stride;
  guchar *src_data, *dst_data;
  guchar *src_row, *dst_row;
  int alpha;
  GdkPixbuf *colored;
  guint8 fg_pixel[4], success_pixel[4], warning_pixel[4], error_pixel[4];

  alpha = fg_color->alpha * 255;

  rgba_to_pixel (fg_color, fg_pixel);
  rgba_to_pixel (success_color, success_pixel);
  rgba_to_pixel (warning_color, warning_pixel);
  rgba_to_pixel (error_color, error_pixel);

  width = gdk_pixbuf_get_width (symbolic);
  height = gdk_pixbuf_get_height (symbolic);

  colored = gdk_pixbuf_new (GDK_COLORSPACE_RGB, TRUE, 8, width, height);

  src_stride = gdk_pixbuf_get_rowstride (symbolic);
  src_data = gdk_pixbuf_get_pixels (symbolic);

  dst_data = gdk_pixbuf_get_pixels (colored);
  dst_stride = gdk_pixbuf_get_rowstride (colored);

  for (y = 0; y < height; y++)
    {
      src_row = src_data + src_stride * y;
      dst_row = dst_data + dst_stride * y;
      for (x = 0; x < width; x++)
        {
          guint r, g, b, a;
          int c1, c2, c3, c4;

          a = src_row[3];
          dst_row[3] = a * alpha / 255;

          if (a == 0)
            {
              dst_row[0] = 0;
              dst_row[1] = 0;
              dst_row[2] = 0;
            }
          else
            {
              c2 = src_row[0];
              c3 = src_row[1];
              c4 = src_row[2];

              if (c2 == 0 && c3 == 0 && c4 == 0)
                {
                  dst_row[0] = fg_pixel[0];
                  dst_row[1] = fg_pixel[1];
                  dst_row[2] = fg_pixel[2];
                }
              else
                {
                  c1 = 255 - c2 - c3 - c4;

                  r = fg_pixel[0] * c1 + success_pixel[0] * c2 +  warning_pixel[0] * c3 +  error_pixel[0] * c4;
                  g = fg_pixel[1] * c1 + success_pixel[1] * c2 +  warning_pixel[1] * c3 +  error_pixel[1] * c4;
                  b = fg_pixel[2] * c1 + success_pixel[2] * c2 +  warning_pixel[2] * c3 +  error_pixel[2] * c4;

                  dst_row[0] = r / 255;
                  dst_row[1] = g / 255;
                  dst_row[2] = b / 255;
                }
            }

          src_row += 4;
          dst_row += 4;
        }
    }

  return colored;
}

static GdkPixbuf *
gtk_icon_info_load_symbolic_png (GtkIconInfo    *icon_info,
                                 const GdkRGBA  *fg,
                                 const GdkRGBA  *success_color,
                                 const GdkRGBA  *warning_color,
                                 const GdkRGBA  *error_color,
                                 GError        **error)
{
  GdkRGBA fg_default = { 0.7450980392156863, 0.7450980392156863, 0.7450980392156863, 1.0};
  GdkRGBA success_default = { 0.3046921492332342,0.6015716792553597, 0.023437857633325704, 1.0};
  GdkRGBA warning_default = {0.9570458533607996, 0.47266346227206835, 0.2421911955443656, 1.0 };
  GdkRGBA error_default = { 0.796887159533074, 0 ,0, 1.0 };

  if (!icon_info_ensure_scale_and_pixbuf (icon_info))
    {
      if (icon_info->load_error)
        {
          if (error)
            *error = g_error_copy (icon_info->load_error);
        }
      else
        {
          g_set_error_literal (error,
                               GTK_ICON_THEME_ERROR,
                               GTK_ICON_THEME_NOT_FOUND,
                               _("Failed to load icon"));
        }

      return NULL;
    }

  return gtk_icon_theme_color_symbolic_pixbuf (icon_info->pixbuf,
                                               fg ? fg : &fg_default,
                                               success_color ? success_color : &success_default,
                                               warning_color ? warning_color : &warning_default,
                                               error_color ? error_color : &error_default);
}

static GdkPixbuf *
gtk_icon_info_load_symbolic_svg (GtkIconInfo    *icon_info,
                                 const GdkRGBA  *fg,
                                 const GdkRGBA  *success_color,
                                 const GdkRGBA  *warning_color,
                                 const GdkRGBA  *error_color,
                                 GError        **error)
{
  GInputStream *stream;
  GdkPixbuf *pixbuf;
  gchar *css_fg;
  gchar *css_success;
  gchar *css_warning;
  gchar *css_error;
  gchar *data;
  gchar *width;
  gchar *height;
  gchar *file_data, *escaped_file_data;
  gsize file_len;
  gint symbolic_size;
  double alpha;
  gchar alphastr[G_ASCII_DTOSTR_BUF_SIZE];

  alpha = fg->alpha;

  css_fg = rgba_to_string_noalpha (fg);

  css_success = css_warning = css_error = NULL;

  if (warning_color)
    css_warning = rgba_to_string_noalpha (warning_color);
  else
    css_warning = g_strdup ("rgb(245,121,62)");

  if (error_color)
    css_error = rgba_to_string_noalpha (error_color);
  else
    css_error = g_strdup ("rgb(204,0,0)");

  if (success_color)
    css_success = rgba_to_string_noalpha (success_color);
  else
    css_success = g_strdup ("rgb(78,154,6)");

  if (!g_file_load_contents (icon_info->icon_file, NULL, &file_data, &file_len, NULL, error))
    return NULL;

  if (!icon_info_ensure_scale_and_pixbuf (icon_info))
    {
      g_propagate_error (error, icon_info->load_error);
      icon_info->load_error = NULL;
      g_free (css_fg);
      g_free (css_warning);
      g_free (css_error);
      g_free (css_success);
      g_free (file_data);
      return NULL;
    }

  if (icon_info->symbolic_width == 0 ||
      icon_info->symbolic_height == 0)
    {
      /* Fetch size from the original icon */
      stream = g_memory_input_stream_new_from_data (file_data, file_len, NULL);
      pixbuf = gdk_pixbuf_new_from_stream (stream, NULL, error);
      g_object_unref (stream);

      if (!pixbuf)
        {
          g_free (css_fg);
          g_free (css_warning);
          g_free (css_error);
          g_free (css_success);
          g_free (file_data);
          return NULL;
        }

      icon_info->symbolic_width = gdk_pixbuf_get_width (pixbuf);
      icon_info->symbolic_height = gdk_pixbuf_get_height (pixbuf);
      g_object_unref (pixbuf);
    }

  symbolic_size = MAX (icon_info->symbolic_width, icon_info->symbolic_height);

  GTK_NOTE (ICONTHEME,
  if (icon_info->dir_type == ICON_THEME_DIR_UNTHEMED)
    g_message ("Symbolic icon %s is not in an icon theme directory",
               icon_info->key.icon_names ? icon_info->key.icon_names[0] : icon_info->filename);
  else if (icon_info->dir_size * icon_info->dir_scale != symbolic_size)
    g_message ("Symbolic icon %s of size %d is in an icon theme directory of size %d",
               icon_info->key.icon_names ? icon_info->key.icon_names[0] : icon_info->filename,
               symbolic_size,
               icon_info->dir_size * icon_info->dir_scale)
  );

  width = g_strdup_printf ("%d", icon_info->symbolic_width);
  height = g_strdup_printf ("%d", icon_info->symbolic_height);

  escaped_file_data = g_markup_escape_text (file_data, file_len);
  g_free (file_data);

  g_ascii_dtostr (alphastr, G_ASCII_DTOSTR_BUF_SIZE, CLAMP (alpha, 0, 1));

  data = g_strconcat ("<?xml version=\"1.0\" encoding=\"UTF-8\" standalone=\"no\"?>\n"
                      "<svg version=\"1.1\"\n"
                      "     xmlns=\"http://www.w3.org/2000/svg\"\n"
                      "     xmlns:xi=\"http://www.w3.org/2001/XInclude\"\n"
                      "     width=\"", width, "\"\n"
                      "     height=\"", height, "\">\n"
                      "  <style type=\"text/css\">\n"
                      "    rect,path {\n"
                      "      fill: ", css_fg," !important;\n"
                      "    }\n"
                      "    .warning {\n"
                      "      fill: ", css_warning, " !important;\n"
                      "    }\n"
                      "    .error {\n"
                      "      fill: ", css_error ," !important;\n"
                      "    }\n"
                      "    .success {\n"
                      "      fill: ", css_success, " !important;\n"
                      "    }\n"
                      "  </style>\n"
                      "  <g opacity=\"", alphastr, "\" ><xi:include href=\"data:text/xml,", escaped_file_data, "\"/></g>\n"
                      "</svg>",
                      NULL);
  g_free (escaped_file_data);
  g_free (css_fg);
  g_free (css_warning);
  g_free (css_error);
  g_free (css_success);
  g_free (width);
  g_free (height);

  stream = g_memory_input_stream_new_from_data (data, -1, g_free);
  pixbuf = gdk_pixbuf_new_from_stream_at_scale (stream,
                                                gdk_pixbuf_get_width (icon_info->pixbuf),
                                                gdk_pixbuf_get_height (icon_info->pixbuf),
                                                TRUE,
                                                NULL,
                                                error);
  g_object_unref (stream);

  return pixbuf;
}


static GdkPixbuf *
gtk_icon_info_load_symbolic_internal (GtkIconInfo    *icon_info,
				      const GdkRGBA  *fg,
				      const GdkRGBA  *success_color,
				      const GdkRGBA  *warning_color,
				      const GdkRGBA  *error_color,
				      gboolean        use_cache,
				      GError        **error)
{
  GdkPixbuf *pixbuf;
  SymbolicPixbufCache *symbolic_cache;
  char *icon_uri;

  if (use_cache)
    {
      symbolic_cache = symbolic_pixbuf_cache_matches (icon_info->symbolic_pixbuf_cache,
						      fg, success_color, warning_color, error_color);
      if (symbolic_cache)
	return symbolic_cache_get_proxy (symbolic_cache, icon_info);
    }

  /* css_fg can't possibly have failed, otherwise
   * that would mean we have a broken style
   */
  g_return_val_if_fail (fg != NULL, NULL);

  icon_uri = g_file_get_uri (icon_info->icon_file);
  if (g_str_has_suffix (icon_uri, ".symbolic.png"))
    pixbuf = gtk_icon_info_load_symbolic_png (icon_info, fg, success_color, warning_color, error_color, error);
  else
    pixbuf = gtk_icon_info_load_symbolic_svg (icon_info, fg, success_color, warning_color, error_color, error);

  g_free (icon_uri);

  if (pixbuf != NULL)
    {
      GdkPixbuf *icon;

      icon = apply_emblems_to_pixbuf (pixbuf, icon_info);
      if (icon != NULL)
        {
          g_object_unref (pixbuf);
          pixbuf = icon;
        }

      if (use_cache)
        {
          icon_info->symbolic_pixbuf_cache =
            symbolic_pixbuf_cache_new (pixbuf, fg, success_color, warning_color, error_color,
                                       icon_info->symbolic_pixbuf_cache);
          g_object_unref (pixbuf);
          return symbolic_cache_get_proxy (icon_info->symbolic_pixbuf_cache, icon_info);
        }
      else
        return pixbuf;
    }

  return NULL;
}

/**
 * gtk_icon_info_load_symbolic:
 * @icon_info: a #GtkIconInfo
 * @fg: a #GdkRGBA representing the foreground color of the icon
 * @success_color: (allow-none): a #GdkRGBA representing the warning color
 *     of the icon or %NULL to use the default color
 * @warning_color: (allow-none): a #GdkRGBA representing the warning color
 *     of the icon or %NULL to use the default color
 * @error_color: (allow-none): a #GdkRGBA representing the error color
 *     of the icon or %NULL to use the default color (allow-none)
 * @was_symbolic: (out) (allow-none): a #gboolean, returns whether the
 *     loaded icon was a symbolic one and whether the @fg color was
 *     applied to it.
 * @error: (allow-none): location to store error information on failure,
 *     or %NULL.
 *
 * Loads an icon, modifying it to match the system colours for the foreground,
 * success, warning and error colors provided. If the icon is not a symbolic
 * one, the function will return the result from gtk_icon_info_load_icon().
 *
 * This allows loading symbolic icons that will match the system theme.
 *
 * Unless you are implementing a widget, you will want to use
 * g_themed_icon_new_with_default_fallbacks() to load the icon.
 *
 * As implementation details, the icon loaded needs to be of SVG type,
 * contain the “symbolic” term as the last component of the icon name,
 * and use the “fg”, “success”, “warning” and “error” CSS styles in the
 * SVG file itself.
 *
 * See the [Symbolic Icons Specification](http://www.freedesktop.org/wiki/SymbolicIcons)
 * for more information about symbolic icons.
 *
 * Returns: (transfer full): a #GdkPixbuf representing the loaded icon
 *
 * Since: 3.0
 */
GdkPixbuf *
gtk_icon_info_load_symbolic (GtkIconInfo    *icon_info,
                             const GdkRGBA  *fg,
                             const GdkRGBA  *success_color,
                             const GdkRGBA  *warning_color,
                             const GdkRGBA  *error_color,
                             gboolean       *was_symbolic,
                             GError        **error)
{
  gboolean is_symbolic;

  g_return_val_if_fail (icon_info != NULL, NULL);
  g_return_val_if_fail (fg != NULL, NULL);

  is_symbolic = gtk_icon_info_is_symbolic (icon_info);

  if (was_symbolic)
    *was_symbolic = is_symbolic;

  if (!is_symbolic)
    return gtk_icon_info_load_icon (icon_info, error);

  return gtk_icon_info_load_symbolic_internal (icon_info,
                                               fg, success_color,
                                               warning_color, error_color,
                                               TRUE,
                                               error);
}

void
gtk_icon_theme_lookup_symbolic_colors (GtkCssStyle *style,
                                       GdkRGBA     *color_out,
                                       GdkRGBA     *success_out,
                                       GdkRGBA     *warning_out,
                                       GdkRGBA     *error_out)
{
  GtkCssValue *palette, *color;
  const GdkRGBA *lookup;

  color = gtk_css_style_get_value (style, GTK_CSS_PROPERTY_COLOR);
  palette = gtk_css_style_get_value (style, GTK_CSS_PROPERTY_ICON_PALETTE);
  *color_out = *_gtk_css_rgba_value_get_rgba (color);

  lookup = gtk_css_palette_value_get_color (palette, "success");
  if (lookup)
    *success_out = *lookup;
  else
    *success_out = *color_out;

  lookup = gtk_css_palette_value_get_color (palette, "warning");
  if (lookup)
    *warning_out = *lookup;
  else
    *warning_out = *color_out;

  lookup = gtk_css_palette_value_get_color (palette, "error");
  if (lookup)
    *error_out = *lookup;
  else
    *error_out = *color_out;
}

/**
 * gtk_icon_info_load_symbolic_for_context:
 * @icon_info: a #GtkIconInfo
 * @context: a #GtkStyleContext
 * @was_symbolic: (out) (allow-none): a #gboolean, returns whether the
 *     loaded icon was a symbolic one and whether the @fg color was
 *     applied to it.
 * @error: (allow-none): location to store error information on failure,
 *     or %NULL.
 *
 * Loads an icon, modifying it to match the system colors for the foreground,
 * success, warning and error colors provided. If the icon is not a symbolic
 * one, the function will return the result from gtk_icon_info_load_icon().
 * This function uses the regular foreground color and the symbolic colors
 * with the names “success_color”, “warning_color” and “error_color” from
 * the context.
 *
 * This allows loading symbolic icons that will match the system theme.
 *
 * See gtk_icon_info_load_symbolic() for more details.
 *
 * Returns: (transfer full): a #GdkPixbuf representing the loaded icon
 *
 * Since: 3.0
 */
GdkPixbuf *
gtk_icon_info_load_symbolic_for_context (GtkIconInfo      *icon_info,
                                         GtkStyleContext  *context,
                                         gboolean         *was_symbolic,
                                         GError          **error)
{
  GdkRGBA fg;
  GdkRGBA success_color;
  GdkRGBA warning_color;
  GdkRGBA error_color;
  gboolean is_symbolic;

  g_return_val_if_fail (icon_info != NULL, NULL);
  g_return_val_if_fail (context != NULL, NULL);

  is_symbolic = gtk_icon_info_is_symbolic (icon_info);

  if (was_symbolic)
    *was_symbolic = is_symbolic;

  if (!is_symbolic)
    return gtk_icon_info_load_icon (icon_info, error);

  gtk_icon_theme_lookup_symbolic_colors (gtk_style_context_lookup_style (context),
                                         &fg, &success_color,
                                         &warning_color, &error_color);

  return gtk_icon_info_load_symbolic_internal (icon_info,
                                               &fg, &success_color,
                                               &warning_color, &error_color,
                                               TRUE,
                                               error);
}

typedef struct {
  gboolean is_symbolic;
  GtkIconInfo *dup;
  GdkRGBA fg;
  gboolean fg_set;
  GdkRGBA success_color;
  gboolean success_color_set;
  GdkRGBA warning_color;
  gboolean warning_color_set;
  GdkRGBA error_color;
  gboolean error_color_set;
} AsyncSymbolicData;

static void
async_symbolic_data_free (AsyncSymbolicData *data)
{
  if (data->dup)
    g_object_unref (data->dup);
  g_slice_free (AsyncSymbolicData, data);
}

static void
async_load_no_symbolic_cb (GObject      *source_object,
                           GAsyncResult *res,
                           gpointer      user_data)
{
  GtkIconInfo *icon_info = GTK_ICON_INFO (source_object);
  GTask *task = user_data;
  GError *error = NULL;
  GdkPixbuf *pixbuf;

  pixbuf = gtk_icon_info_load_icon_finish (icon_info, res, &error);
  if (pixbuf == NULL)
    g_task_return_error (task, error);
  else
    g_task_return_pointer (task, pixbuf, g_object_unref);
  g_object_unref (task);
}

static void
load_symbolic_icon_thread  (GTask        *task,
                            gpointer      source_object,
                            gpointer      task_data,
                            GCancellable *cancellable)
{
  AsyncSymbolicData *data = task_data;
  GError *error;
  GdkPixbuf *pixbuf;

  error = NULL;
  pixbuf = gtk_icon_info_load_symbolic_internal (data->dup,
                                                 data->fg_set ? &data->fg : NULL,
                                                 data->success_color_set ? &data->success_color : NULL,
                                                 data->warning_color_set ? &data->warning_color : NULL,
                                                 data->error_color_set ? &data->error_color : NULL,
                                                 FALSE,
                                                 &error);
  if (pixbuf == NULL)
    g_task_return_error (task, error);
  else
    g_task_return_pointer (task, pixbuf, g_object_unref);
}

/**
 * gtk_icon_info_load_symbolic_async:
 * @icon_info: a #GtkIconInfo from gtk_icon_theme_lookup_icon()
 * @fg: a #GdkRGBA representing the foreground color of the icon
 * @success_color: (allow-none): a #GdkRGBA representing the warning color
 *     of the icon or %NULL to use the default color
 * @warning_color: (allow-none): a #GdkRGBA representing the warning color
 *     of the icon or %NULL to use the default color
 * @error_color: (allow-none): a #GdkRGBA representing the error color
 *     of the icon or %NULL to use the default color (allow-none)
 * @cancellable: (allow-none): optional #GCancellable object,
 *     %NULL to ignore
 * @callback: (scope async): a #GAsyncReadyCallback to call when the
 *     request is satisfied
 * @user_data: (closure): the data to pass to callback function
 *
 * Asynchronously load, render and scale a symbolic icon previously looked up
 * from the icon theme using gtk_icon_theme_lookup_icon().
 *
 * For more details, see gtk_icon_info_load_symbolic() which is the synchronous
 * version of this call.
 *
 * Since: 3.8
 */
void
gtk_icon_info_load_symbolic_async (GtkIconInfo          *icon_info,
                                   const GdkRGBA        *fg,
                                   const GdkRGBA        *success_color,
                                   const GdkRGBA        *warning_color,
                                   const GdkRGBA        *error_color,
                                   GCancellable         *cancellable,
                                   GAsyncReadyCallback   callback,
                                   gpointer              user_data)
{
  GTask *task;
  AsyncSymbolicData *data;
  SymbolicPixbufCache *symbolic_cache;
  GdkPixbuf *pixbuf;

  g_return_if_fail (icon_info != NULL);
  g_return_if_fail (fg != NULL);

  task = g_task_new (icon_info, cancellable, callback, user_data);

  data = g_slice_new0 (AsyncSymbolicData);
  g_task_set_task_data (task, data, (GDestroyNotify) async_symbolic_data_free);

  data->is_symbolic = gtk_icon_info_is_symbolic (icon_info);

  if (!data->is_symbolic)
    {
      gtk_icon_info_load_icon_async (icon_info, cancellable, async_load_no_symbolic_cb, g_object_ref (task));
    }
  else
    {
      symbolic_cache = symbolic_pixbuf_cache_matches (icon_info->symbolic_pixbuf_cache,
                                                      fg, success_color, warning_color, error_color);
      if (symbolic_cache)
        {
          pixbuf = symbolic_cache_get_proxy (symbolic_cache, icon_info);
          g_task_return_pointer (task, pixbuf, g_object_unref);
        }
      else
        {
          if (fg)
            {
              data->fg = *fg;
              data->fg_set = TRUE;
            }

          if (success_color)
            {
              data->success_color = *success_color;
              data->success_color_set = TRUE;
            }

          if (warning_color)
            {
              data->warning_color = *warning_color;
              data->warning_color_set = TRUE;
            }

          if (error_color)
            {
              data->error_color = *error_color;
              data->error_color_set = TRUE;
            }

          data->dup = icon_info_dup (icon_info);
          g_task_run_in_thread (task, load_symbolic_icon_thread);
        }
    }
  g_object_unref (task);
}

/**
 * gtk_icon_info_load_symbolic_finish:
 * @icon_info: a #GtkIconInfo from gtk_icon_theme_lookup_icon()
 * @res: a #GAsyncResult
 * @was_symbolic: (out) (allow-none): a #gboolean, returns whether the
 *     loaded icon was a symbolic one and whether the @fg color was
 *     applied to it.
 * @error: (allow-none): location to store error information on failure,
 *     or %NULL.
 *
 * Finishes an async icon load, see gtk_icon_info_load_symbolic_async().
 *
 * Returns: (transfer full): the rendered icon; this may be a newly
 *     created icon or a new reference to an internal icon, so you must
 *     not modify the icon. Use g_object_unref() to release your reference
 *     to the icon.
 *
 * Since: 3.8
 */
GdkPixbuf *
gtk_icon_info_load_symbolic_finish (GtkIconInfo   *icon_info,
                                    GAsyncResult  *result,
                                    gboolean      *was_symbolic,
                                    GError       **error)
{
  GTask *task = G_TASK (result);
  AsyncSymbolicData *data = g_task_get_task_data (task);
  SymbolicPixbufCache *symbolic_cache;
  GdkPixbuf *pixbuf;

  if (was_symbolic)
    *was_symbolic = data->is_symbolic;

  if (data->dup && !g_task_had_error (task))
    {
      pixbuf = g_task_propagate_pointer (task, NULL);

      g_assert (pixbuf != NULL); /* we checked for !had_error above */

      symbolic_cache = symbolic_pixbuf_cache_matches (icon_info->symbolic_pixbuf_cache,
                                                      data->fg_set ? &data->fg : NULL,
                                                      data->success_color_set ? &data->success_color : NULL,
                                                      data->warning_color_set ? &data->warning_color : NULL,
                                                      data->error_color_set ? &data->error_color : NULL);

      if (symbolic_cache == NULL)
        {
          symbolic_cache = icon_info->symbolic_pixbuf_cache =
            symbolic_pixbuf_cache_new (pixbuf,
                                       data->fg_set ? &data->fg : NULL,
                                       data->success_color_set ? &data->success_color : NULL,
                                       data->warning_color_set ? &data->warning_color : NULL,
                                       data->error_color_set ? &data->error_color : NULL,
                                       icon_info->symbolic_pixbuf_cache);
        }

      g_object_unref (pixbuf);

      return symbolic_cache_get_proxy (symbolic_cache, icon_info);
    }

  return g_task_propagate_pointer (task, error);
}

/**
 * gtk_icon_info_load_symbolic_for_context_async:
 * @icon_info: a #GtkIconInfo from gtk_icon_theme_lookup_icon()
 * @context: a #GtkStyleContext
 * @cancellable: (allow-none): optional #GCancellable object,
 *     %NULL to ignore
 * @callback: (scope async): a #GAsyncReadyCallback to call when the
 *     request is satisfied
 * @user_data: (closure): the data to pass to callback function
 *
 * Asynchronously load, render and scale a symbolic icon previously
 * looked up from the icon theme using gtk_icon_theme_lookup_icon().
 *
 * For more details, see gtk_icon_info_load_symbolic_for_context()
 * which is the synchronous version of this call.
 *
 * Since: 3.8
 */
void
gtk_icon_info_load_symbolic_for_context_async (GtkIconInfo         *icon_info,
                                               GtkStyleContext     *context,
                                               GCancellable        *cancellable,
                                               GAsyncReadyCallback  callback,
                                               gpointer             user_data)
{
  GdkRGBA fg;
  GdkRGBA success_color;
  GdkRGBA warning_color;
  GdkRGBA error_color;

  g_return_if_fail (icon_info != NULL);
  g_return_if_fail (context != NULL);

  gtk_icon_theme_lookup_symbolic_colors (gtk_style_context_lookup_style (context),
                                         &fg, &success_color,
                                         &warning_color, &error_color);

  gtk_icon_info_load_symbolic_async (icon_info,
                                     &fg, &success_color,
                                     &warning_color, &error_color,
                                     cancellable, callback, user_data);
}

/**
 * gtk_icon_info_load_symbolic_for_context_finish:
 * @icon_info: a #GtkIconInfo from gtk_icon_theme_lookup_icon()
 * @res: a #GAsyncResult
 * @was_symbolic: (out) (allow-none): a #gboolean, returns whether the
 *     loaded icon was a symbolic one and whether the @fg color was
 *     applied to it.
 * @error: (allow-none): location to store error information on failure,
 *     or %NULL.
 *
 * Finishes an async icon load, see gtk_icon_info_load_symbolic_for_context_async().
 *
 * Returns: (transfer full): the rendered icon; this may be a newly
 *     created icon or a new reference to an internal icon, so you must
 *     not modify the icon. Use g_object_unref() to release your reference
 *     to the icon.
 *
 * Since: 3.8
 */
GdkPixbuf *
gtk_icon_info_load_symbolic_for_context_finish (GtkIconInfo   *icon_info,
                                                GAsyncResult  *result,
                                                gboolean      *was_symbolic,
                                                GError       **error)
{
  return gtk_icon_info_load_symbolic_finish (icon_info, result, was_symbolic, error);
}

/* Look up a builtin icon; the min_difference_p and
 * has_larger_p out parameters allow us to combine
 * this lookup with searching through the actual directories
 * of the “hicolor” icon theme. See theme_lookup_icon()
 * for how they are used.
 */
static BuiltinIcon *
find_builtin_icon (const gchar *icon_name,
                   gint         size,
                   gint         scale,
                   gint        *min_difference_p)
{
  GSList *icons = NULL;
  gint min_difference = G_MAXINT;
  gboolean has_larger = FALSE;
  BuiltinIcon *min_icon = NULL;
  
  if (!icon_theme_builtin_icons)
    return NULL;

  size *= scale;

  icons = g_hash_table_lookup (icon_theme_builtin_icons, icon_name);

  while (icons)
    {
      BuiltinIcon *default_icon = icons->data;
      int min, max, difference;
      gboolean smaller;
      
      min = default_icon->size - 2;
      max = default_icon->size + 2;
      smaller = size < min;
      if (size < min)
        difference = min - size;
      else if (size > max)
        difference = size - max;
      else
        difference = 0;
      
      if (difference == 0)
        {
          min_icon = default_icon;
          break;
        }
      
      if (!has_larger)
        {
          if (difference < min_difference || smaller)
            {
              min_difference = difference;
              min_icon = default_icon;
              has_larger = smaller;
            }
        }
      else
        {
          if (difference < min_difference && smaller)
            {
              min_difference = difference;
              min_icon = default_icon;
            }
        }
      
      icons = icons->next;
    }

  if (min_difference_p)
    *min_difference_p = min_difference;

  return min_icon;
}

/**
 * gtk_icon_theme_lookup_by_gicon:
 * @icon_theme: a #GtkIconTheme
 * @icon: the #GIcon to look up
 * @size: desired icon size
 * @flags: flags modifying the behavior of the icon lookup
 * 
 * Looks up an icon and returns a #GtkIconInfo containing information
 * such as the filename of the icon. The icon can then be rendered
 * into a pixbuf using gtk_icon_info_load_icon().
 *
 * When rendering on displays with high pixel densities you should not
 * use a @size multiplied by the scaling factor returned by functions
 * like gdk_window_get_scale_factor(). Instead, you should use
 * gtk_icon_theme_lookup_by_gicon_for_scale(), as the assets loaded
 * for a given scaling factor may be different.
 *
 * Returns: (nullable) (transfer full): a #GtkIconInfo containing
 *     information about the icon, or %NULL if the icon wasn’t
 *     found. Unref with g_object_unref()
 *
 * Since: 2.14
 */
GtkIconInfo *
gtk_icon_theme_lookup_by_gicon (GtkIconTheme       *icon_theme,
                                GIcon              *icon,
                                gint                size,
                                GtkIconLookupFlags  flags)
{
  return gtk_icon_theme_lookup_by_gicon_for_scale (icon_theme, icon,
                                                   size, 1, flags);
}


/**
 * gtk_icon_theme_lookup_by_gicon_for_scale:
 * @icon_theme: a #GtkIconTheme
 * @icon: the #GIcon to look up
 * @size: desired icon size
 * @scale: the desired scale
 * @flags: flags modifying the behavior of the icon lookup
 *
 * Looks up an icon and returns a #GtkIconInfo containing information
 * such as the filename of the icon. The icon can then be rendered into
 * a pixbuf using gtk_icon_info_load_icon().
 *
 * Returns: (nullable) (transfer full): a #GtkIconInfo containing
 *     information about the icon, or %NULL if the icon wasn’t
 *     found. Unref with g_object_unref()
 *
 * Since: 3.10
 */
GtkIconInfo *
gtk_icon_theme_lookup_by_gicon_for_scale (GtkIconTheme       *icon_theme,
                                          GIcon              *icon,
                                          gint                size,
                                          gint                scale,
                                          GtkIconLookupFlags  flags)
{
  GtkIconInfo *info;

  g_return_val_if_fail (GTK_IS_ICON_THEME (icon_theme), NULL);
  g_return_val_if_fail (G_IS_ICON (icon), NULL);
  g_warn_if_fail ((flags & GTK_ICON_LOOKUP_GENERIC_FALLBACK) == 0);

  if (GDK_IS_PIXBUF (icon))
    {
      GdkPixbuf *pixbuf;

      pixbuf = GDK_PIXBUF (icon);

      if ((flags & GTK_ICON_LOOKUP_FORCE_SIZE) != 0)
        {
          gint width, height, max;
          gdouble pixbuf_scale;
          GdkPixbuf *scaled;

          width = gdk_pixbuf_get_width (pixbuf);
          height = gdk_pixbuf_get_height (pixbuf);
          max = MAX (width, height);
          pixbuf_scale = (gdouble) size * scale / (gdouble) max;

          scaled = gdk_pixbuf_scale_simple (pixbuf,
                                            0.5 + width * pixbuf_scale,
                                            0.5 + height * pixbuf_scale,
                                            GDK_INTERP_BILINEAR);

          info = gtk_icon_info_new_for_pixbuf (icon_theme, scaled);

          g_object_unref (scaled);
        }
      else
        {
          info = gtk_icon_info_new_for_pixbuf (icon_theme, pixbuf);
        }

      return info;
    }
  else if (G_IS_FILE_ICON (icon))
    {
      GFile *file = g_file_icon_get_file (G_FILE_ICON (icon));

      info = gtk_icon_info_new_for_file (file, size, scale);
      info->forced_size = (flags & GTK_ICON_LOOKUP_FORCE_SIZE) != 0;

      return info;
    }
  else if (G_IS_LOADABLE_ICON (icon))
    {
      info = icon_info_new (ICON_THEME_DIR_UNTHEMED, size, 1);
      info->loadable = G_LOADABLE_ICON (g_object_ref (icon));
      info->is_svg = FALSE;
      info->desired_size = size;
      info->desired_scale = scale;
      info->forced_size = (flags & GTK_ICON_LOOKUP_FORCE_SIZE) != 0;

      return info;
    }
  else if (G_IS_THEMED_ICON (icon))
    {
      const gchar **names;

      names = (const gchar **)g_themed_icon_get_names (G_THEMED_ICON (icon));
      info = gtk_icon_theme_choose_icon_for_scale (icon_theme, names, size, scale, flags);

      return info;
    }
  else if (G_IS_EMBLEMED_ICON (icon))
    {
      GIcon *base, *emblem;
      GList *list, *l;
      GtkIconInfo *base_info, *emblem_info;

      base = g_emblemed_icon_get_icon (G_EMBLEMED_ICON (icon));
      base_info = gtk_icon_theme_lookup_by_gicon_for_scale (icon_theme, base, size, scale, flags);
      if (base_info)
        {
          info = icon_info_dup (base_info);
          g_object_unref (base_info);

          list = g_emblemed_icon_get_emblems (G_EMBLEMED_ICON (icon));
          for (l = list; l; l = l->next)
            {
              emblem = g_emblem_get_icon (G_EMBLEM (l->data));
              /* always force size for emblems */
              emblem_info = gtk_icon_theme_lookup_by_gicon_for_scale (icon_theme, emblem, size / 2, scale, flags | GTK_ICON_LOOKUP_FORCE_SIZE);
              if (emblem_info)
                info->emblem_infos = g_slist_prepend (info->emblem_infos, emblem_info);
            }

          return info;
        }
      else
        return NULL;
    }

  return NULL;
}

/**
 * gtk_icon_info_new_for_pixbuf:
 * @icon_theme: a #GtkIconTheme
 * @pixbuf: the pixbuf to wrap in a #GtkIconInfo
 *
 * Creates a #GtkIconInfo for a #GdkPixbuf.
 *
 * Returns: (transfer full): a #GtkIconInfo
 *
 * Since: 2.14
 */
GtkIconInfo *
gtk_icon_info_new_for_pixbuf (GtkIconTheme *icon_theme,
                              GdkPixbuf    *pixbuf)
{
  GtkIconInfo *info;

  g_return_val_if_fail (GTK_IS_ICON_THEME (icon_theme), NULL);
  g_return_val_if_fail (GDK_IS_PIXBUF (pixbuf), NULL);

  info = icon_info_new (ICON_THEME_DIR_UNTHEMED, 0, 1);
  info->pixbuf = g_object_ref (pixbuf);
  info->scale = 1.0;

  return info;
}

GtkIconInfo *
gtk_icon_info_new_for_file (GFile *file,
                            gint   size,
                            gint   scale)
{
  GtkIconInfo *info;

  info = icon_info_new (ICON_THEME_DIR_UNTHEMED, size, 1);
  info->loadable = G_LOADABLE_ICON (g_file_icon_new (file));
  info->icon_file = g_object_ref (file);
  info->is_resource = g_file_has_uri_scheme (file, "resource");

  if (info->is_resource)
    {
      gchar *uri;

      uri = g_file_get_uri (file);
      info->filename = g_strdup (uri + 11); /* resource:// */
      g_free (uri);
    }
  else
    {
      info->filename = g_file_get_path (file);
    }

  info->is_svg = suffix_from_name (info->filename) == ICON_SUFFIX_SVG;

 info->desired_size = size;
 info->desired_scale = scale;
 info->forced_size = FALSE;

 return info;
}

typedef struct _IconSize IconSize;

struct _IconSize
{
  const char *name;

  int width;
  int height;
};

static const IconSize icon_sizes[] = {
  [GTK_ICON_SIZE_INVALID] = {
    .name = NULL,
    .width = 0,
    .height = 0,
  },
  [GTK_ICON_SIZE_MENU] = {
    .name = "gtk-menu",
    .width = 16,
    .height = 16,
  },
  [GTK_ICON_SIZE_BUTTON] = {
    .name = "gtk-button",
    .width = 16,
    .height = 16,
  },
  [GTK_ICON_SIZE_SMALL_TOOLBAR] = {
    .name = "gtk-small-toolbar",
    .width = 16,
    .height = 16,
  },
  [GTK_ICON_SIZE_LARGE_TOOLBAR] = {
    .name = "gtk-large-toolbar",
    .width = 24,
    .height = 24,
  },
  [GTK_ICON_SIZE_DND] = {
    .name = "gtk-dnd",
    .width = 32,
    .height = 32,
  },
  [GTK_ICON_SIZE_DIALOG] = {
    .name = "gtk-dialog",
    .width = 48,
    .height = 48,
  },
};

/**
 * gtk_icon_size_lookup:
 * @size: (type int): an icon size (#GtkIconSize)
 * @width: (out) (optional): location to store icon width
 * @height: (out) (optional): location to store icon height
 *
 * Obtains the pixel size of a semantic icon size @size:
 * #GTK_ICON_SIZE_MENU, #GTK_ICON_SIZE_BUTTON, etc.  This function
 * isn’t normally needed, gtk_icon_theme_load_icon() is the usual
 * way to get an icon for rendering, then just look at the size of
 * the rendered pixbuf. The rendered pixbuf may not even correspond to
 * the width/height returned by gtk_icon_size_lookup(), because themes
 * are free to render the pixbuf however they like, including changing
 * the usual size.
 *
 * Returns: %TRUE if @size was a valid size
 */
gboolean
gtk_icon_size_lookup (GtkIconSize  size,
                      gint        *widthp,
                      gint        *heightp)
{
  GTK_NOTE (MULTIHEAD,
            g_warning ("gtk_icon_size_lookup ()) is not multihead safe"));

  if (size == (GtkIconSize)-1)
    return FALSE;

  if (size >= G_N_ELEMENTS (icon_sizes))
    return FALSE;

  if (size == GTK_ICON_SIZE_INVALID)
    return FALSE;

  if (widthp)
    *widthp = icon_sizes[size].width;

  if (heightp)
    *heightp = icon_sizes[size].height;

  return TRUE;
}