gtk2/gtk/gtkrecentmanager.c

/* GTK - The GIMP Toolkit
 * gtkrecentmanager.c: a manager for the recently used resources
 *
 * Copyright (C) 2006 Emmanuele Bassi
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Library 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
 * Library General Public License for more details.
 *
 * You should have received a copy of the GNU Library General Public
 * License along with this library. If not, see <http://www.gnu.org/licenses/>.
 */

/**
 * SECTION:gtkrecentmanager
 * @Title: GtkRecentManager
 * @short_description: Managing recently used files
 * @See_Also: #GBookmarkFile, #GtkSettings, #GtkRecentChooser
 *
 * #GtkRecentManager provides a facility for adding, removing and
 * looking up recently used files. Each recently used file is
 * identified by its URI, and has meta-data associated to it, like
 * the names and command lines of the applications that have
 * registered it, the number of time each application has registered
 * the same file, the mime type of the file and whether the file
 * should be displayed only by the applications that have
 * registered it.
 *
 * The recently used files list is per user.
 *
 * The #GtkRecentManager acts like a database of all the recently
 * used files. You can create new #GtkRecentManager objects, but
 * it is more efficient to use the default manager created by GTK+.
 *
 * Adding a new recently used file is as simple as:
 *
 * |[<!-- language="C" -->
 * GtkRecentManager *manager;
 *
 * manager = gtk_recent_manager_get_default ();
 * gtk_recent_manager_add_item (manager, file_uri);
 * ]|
 *
 * The #GtkRecentManager will try to gather all the needed information
 * from the file itself through GIO.
 *
 * Looking up the meta-data associated with a recently used file
 * given its URI requires calling gtk_recent_manager_lookup_item():
 *
 * |[<!-- language="C" -->
 * GtkRecentManager *manager;
 * GtkRecentInfo *info;
 * GError *error = NULL;
 *
 * manager = gtk_recent_manager_get_default ();
 * info = gtk_recent_manager_lookup_item (manager, file_uri, &error);
 * if (error)
 *   {
 *     g_warning ("Could not find the file: %s", error->message);
 *     g_error_free (error);
 *   }
 * else
 *  {
 *    // Use the info object
 *    gtk_recent_info_unref (info);
 *  }
 * ]|
 *
 * In order to retrieve the list of recently used files, you can use
 * gtk_recent_manager_get_items(), which returns a list of #GtkRecentInfo-structs.
 *
 * A #GtkRecentManager is the model used to populate the contents of
 * one, or more #GtkRecentChooser implementations.
 *
 * Note that the maximum age of the recently used files list is
 * controllable through the #GtkSettings:gtk-recent-files-max-age
 * property.
 *
 * Recently used files are supported since GTK+ 2.10.
 */

#include "config.h"

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

#include "gtkrecentmanager.h"
#include "gtkintl.h"
#include "gtksettings.h"
#include "gtkicontheme.h"
#include "gtktypebuiltins.h"
#include "gtkprivate.h"
#include "gtkmarshalers.h"

/* the file where we store the recently used items */
#define GTK_RECENTLY_USED_FILE  "recently-used.xbel"

/* return all items by default */
#define DEFAULT_LIMIT   -1

/* keep in sync with xdgmime */
#define GTK_RECENT_DEFAULT_MIME "application/octet-stream"

typedef struct
{
  gchar *name;
  gchar *exec;

  guint count;

  time_t stamp;
} RecentAppInfo;

/**
 * GtkRecentInfo:
 *
 * #GtkRecentInfo-struct contains private data only, and should
 * be accessed using the provided API.
 *
 * #GtkRecentInfo constains all the meta-data
 * associated with an entry in the recently used files list.
 *
 * Since: 2.10
 */
struct _GtkRecentInfo
{
  gchar *uri;

  gchar *display_name;
  gchar *description;

  time_t added;
  time_t modified;
  time_t visited;

  gchar *mime_type;

  GSList *applications;
  GHashTable *apps_lookup;

  GSList *groups;

  gboolean is_private;

  GdkPixbuf *icon;

  gint ref_count;
};

struct _GtkRecentManagerPrivate
{
  gchar *filename;

  guint is_dirty : 1;

  gint size;

  GBookmarkFile *recent_items;

  GFileMonitor *monitor;

  guint changed_timeout;
  guint changed_age;
};

enum
{
  PROP_0,

  PROP_FILENAME,
  PROP_LIMIT,
  PROP_SIZE
};

static void     gtk_recent_manager_dispose             (GObject           *object);
static void     gtk_recent_manager_finalize            (GObject           *object);
static void     gtk_recent_manager_set_property        (GObject           *object,
                                                        guint              prop_id,
                                                        const GValue      *value,
                                                        GParamSpec        *pspec);
static void     gtk_recent_manager_get_property        (GObject           *object,
                                                        guint              prop_id,
                                                        GValue            *value,
                                                        GParamSpec        *pspec);
static void     gtk_recent_manager_add_item_query_info (GObject           *source_object,
                                                        GAsyncResult      *res,
                                                        gpointer           user_data);
static void     gtk_recent_manager_monitor_changed     (GFileMonitor      *monitor,
                                                        GFile             *file,
                                                        GFile             *other_file,
                                                        GFileMonitorEvent  event_type,
                                                        gpointer           user_data);
static void     gtk_recent_manager_changed             (GtkRecentManager  *manager);
static void     gtk_recent_manager_real_changed        (GtkRecentManager  *manager);
static void     gtk_recent_manager_set_filename        (GtkRecentManager  *manager,
                                                        const gchar       *filename);
static void     gtk_recent_manager_clamp_to_age        (GtkRecentManager  *manager,
                                                        gint               age);
static void     gtk_recent_manager_enabled_changed     (GtkRecentManager  *manager);


static void     build_recent_items_list                (GtkRecentManager  *manager);
static void     purge_recent_items_list                (GtkRecentManager  *manager,
                                                        GError           **error);

static RecentAppInfo *recent_app_info_new  (const gchar   *app_name);
static void           recent_app_info_free (RecentAppInfo *app_info);

static GtkRecentInfo *gtk_recent_info_new  (const gchar   *uri);
static void           gtk_recent_info_free (GtkRecentInfo *recent_info);

static guint signal_changed = 0;

static GtkRecentManager *recent_manager_singleton = NULL;

G_DEFINE_TYPE_WITH_PRIVATE (GtkRecentManager, gtk_recent_manager, G_TYPE_OBJECT)

/* Test of haystack has the needle prefix, comparing case
 * insensitive. haystack may be UTF-8, but needle must
 * contain only lowercase ascii.
 */
static gboolean
has_case_prefix (const gchar *haystack,
                 const gchar *needle)
{
  const gchar *h, *n;

  /* Eat one character at a time. */
  h = haystack;
  n = needle;

  while (*n && *h && *n == g_ascii_tolower (*h))
    {
      n++;
      h++;
    }

  return *n == '\0';
}

GQuark
gtk_recent_manager_error_quark (void)
{
  return g_quark_from_static_string ("gtk-recent-manager-error-quark");
}

static void
gtk_recent_manager_class_init (GtkRecentManagerClass *klass)
{
  GObjectClass *gobject_class = G_OBJECT_CLASS (klass);

  gobject_class->set_property = gtk_recent_manager_set_property;
  gobject_class->get_property = gtk_recent_manager_get_property;
  gobject_class->dispose = gtk_recent_manager_dispose;
  gobject_class->finalize = gtk_recent_manager_finalize;

  /**
   * GtkRecentManager:filename:
   *
   * The full path to the file to be used to store and read the
   * recently used resources list
   *
   * Since: 2.10
   */
  g_object_class_install_property (gobject_class,
                                   PROP_FILENAME,
                                   g_param_spec_string ("filename",
                                                        P_("Filename"),
                                                        P_("The full path to the file to be used to store and read the list"),
                                                        NULL,
                                                        (G_PARAM_CONSTRUCT_ONLY | G_PARAM_READWRITE)));

  /**
   * GtkRecentManager:size:
   *
   * The size of the recently used resources list.
   *
   * Since: 2.10
   */
  g_object_class_install_property (gobject_class,
                                   PROP_SIZE,
                                   g_param_spec_int ("size",
                                                     P_("Size"),
                                                     P_("The size of the recently used resources list"),
                                                     -1,
                                                     G_MAXINT,
                                                     0,
                                                     G_PARAM_READABLE));

  /**
   * GtkRecentManager::changed:
   * @recent_manager: the recent manager
   *
   * Emitted when the current recently used resources manager changes
   * its contents, either by calling gtk_recent_manager_add_item() or
   * by another application.
   *
   * Since: 2.10
   */
  signal_changed =
    g_signal_new (I_("changed"),
                  G_TYPE_FROM_CLASS (klass),
                  G_SIGNAL_RUN_FIRST,
                  G_STRUCT_OFFSET (GtkRecentManagerClass, changed),
                  NULL, NULL,
                  g_cclosure_marshal_VOID__VOID,
                  G_TYPE_NONE, 0);

  klass->changed = gtk_recent_manager_real_changed;
}

static void
gtk_recent_manager_init (GtkRecentManager *manager)
{
  GtkRecentManagerPrivate *priv;
  GtkSettings *settings;

  manager->priv = gtk_recent_manager_get_instance_private (manager);
  priv = manager->priv;

  priv->size = 0;
  priv->filename = NULL;

  settings = gtk_settings_get_default ();
  if (settings)
    g_signal_connect_swapped (settings, "notify::gtk-recent-files-enabled",
                              G_CALLBACK (gtk_recent_manager_enabled_changed), manager);
}

static void
gtk_recent_manager_set_property (GObject      *object,
                                 guint         prop_id,
                                 const GValue *value,
                                 GParamSpec   *pspec)
{
  GtkRecentManager *recent_manager = GTK_RECENT_MANAGER (object);

  switch (prop_id)
    {
    case PROP_FILENAME:
      gtk_recent_manager_set_filename (recent_manager, g_value_get_string (value));
      break;
    default:
      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
      break;
    }
}

static void
gtk_recent_manager_get_property (GObject    *object,
                                 guint       prop_id,
                                 GValue     *value,
                                 GParamSpec *pspec)
{
  GtkRecentManager *recent_manager = GTK_RECENT_MANAGER (object);

  switch (prop_id)
    {
    case PROP_FILENAME:
      g_value_set_string (value, recent_manager->priv->filename);
      break;
    case PROP_SIZE:
      g_value_set_int (value, recent_manager->priv->size);
      break;
    default:
      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
      break;
    }
}

static void
gtk_recent_manager_finalize (GObject *object)
{
  GtkRecentManager *manager = GTK_RECENT_MANAGER (object);
  GtkRecentManagerPrivate *priv = manager->priv;

  g_free (priv->filename);

  if (priv->recent_items != NULL)
    g_bookmark_file_free (priv->recent_items);

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

static void
gtk_recent_manager_dispose (GObject *gobject)
{
  GtkRecentManager *manager = GTK_RECENT_MANAGER (gobject);
  GtkRecentManagerPrivate *priv = manager->priv;

  if (priv->monitor != NULL)
    {
      g_signal_handlers_disconnect_by_func (priv->monitor,
                                            G_CALLBACK (gtk_recent_manager_monitor_changed),
                                            manager);
      g_object_unref (priv->monitor);
      priv->monitor = NULL;
    }

  if (priv->changed_timeout != 0)
    {
      g_source_remove (priv->changed_timeout);
      priv->changed_timeout = 0;
      priv->changed_age = 0;
    }

  if (priv->is_dirty)
    {
      g_object_ref (manager);
      g_signal_emit (manager, signal_changed, 0);
      g_object_unref (manager);
    }

  G_OBJECT_CLASS (gtk_recent_manager_parent_class)->dispose (gobject);
}

static void
gtk_recent_manager_enabled_changed (GtkRecentManager *manager)
{
  manager->priv->is_dirty = TRUE;
  gtk_recent_manager_changed (manager);
}

static void
gtk_recent_manager_real_changed (GtkRecentManager *manager)
{
  GtkRecentManagerPrivate *priv = manager->priv;

  g_object_freeze_notify (G_OBJECT (manager));

  if (priv->is_dirty)
    {
      GError *write_error;

      /* we are marked as dirty, so we dump the content of our
       * recently used items list
       */
      if (!priv->recent_items)
        {
          /* if no container object has been defined, we create a new
           * empty container, and dump it
           */
          priv->recent_items = g_bookmark_file_new ();
          priv->size = 0;
        }
      else
        {
          GtkSettings *settings;
          gint age;
          gboolean enabled;

          settings = gtk_settings_get_default ();
          if (settings)
            g_object_get (G_OBJECT (settings),
                          "gtk-recent-files-max-age", &age,
                          "gtk-recent-files-enabled", &enabled,
                          NULL);
          else
            {
              age = 30;
              enabled = TRUE;
            }

          if (age == 0 || !enabled)
            {
              g_bookmark_file_free (priv->recent_items);
              priv->recent_items = g_bookmark_file_new ();
              priv->size = 0;
            }
          else if (age > 0)
            gtk_recent_manager_clamp_to_age (manager, age);
        }

      if (priv->filename != NULL)
        {
          write_error = NULL;
          g_bookmark_file_to_file (priv->recent_items, priv->filename, &write_error);
          if (write_error)
            {
              gchar *utf8 = g_filename_to_utf8 (priv->filename, -1, NULL, NULL, NULL);
              g_warning ("Attempting to store changes into '%s', but failed: %s",
                         utf8 ? utf8 : "(invalid filename)",
                         write_error->message);
              g_free (utf8);
              g_error_free (write_error);
            }

          if (g_chmod (priv->filename, 0600) < 0)
            {
              gchar *utf8 = g_filename_to_utf8 (priv->filename, -1, NULL, NULL, NULL);
              g_warning ("Attempting to set the permissions of '%s', but failed: %s",
                         utf8 ? utf8 : "(invalid filename)",
                         g_strerror (errno));
              g_free (utf8);
            }
        }

      /* mark us as clean */
      priv->is_dirty = FALSE;
    }
  else
    {
      /* we are not marked as dirty, so we have been called
       * because the recently used resources file has been
       * changed (and not from us).
       */
      build_recent_items_list (manager);
    }

  g_object_thaw_notify (G_OBJECT (manager));
}

static void
gtk_recent_manager_monitor_changed (GFileMonitor      *monitor,
                                    GFile             *file,
                                    GFile             *other_file,
                                    GFileMonitorEvent  event_type,
                                    gpointer           user_data)
{
  GtkRecentManager *manager = user_data;

  switch (event_type)
    {
    case G_FILE_MONITOR_EVENT_CHANGED:
    case G_FILE_MONITOR_EVENT_CREATED:
    case G_FILE_MONITOR_EVENT_DELETED:
      gdk_threads_enter ();
      gtk_recent_manager_changed (manager);
      gdk_threads_leave ();
      break;

    default:
      break;
    }
}

static gchar *
get_default_filename (void)
{
  if (g_mkdir_with_parents (g_get_user_data_dir (), 0755) == -1)
    {
      int saved_errno = errno;

      g_critical ("Unable to create user data directory '%s' for storing "
                  "the recently used files list: %s",
                  g_get_user_data_dir (),
                  g_strerror (saved_errno));

      return NULL;
    }

  return g_build_filename (g_get_user_data_dir (),
                           GTK_RECENTLY_USED_FILE,
                           NULL);
}

static void
gtk_recent_manager_set_filename (GtkRecentManager *manager,
                                 const gchar      *filename)
{
  GtkRecentManagerPrivate *priv;
  GFile *file;
  GError *error;

  g_assert (GTK_IS_RECENT_MANAGER (manager));

  priv = manager->priv;

  /* if a filename is already set and filename is not NULL, then copy
   * it and reset the monitor; otherwise, if it's NULL we're being
   * called from the finalization sequence, so we simply disconnect
   * the monitoring and return.
   *
   * if no filename is set and filename is NULL, use the default.
   */
  if (priv->filename)
    {
      g_free (priv->filename);

      if (priv->monitor)
        {
          g_signal_handlers_disconnect_by_func (priv->monitor,
                                                G_CALLBACK (gtk_recent_manager_monitor_changed),
                                                manager);
          g_object_unref (priv->monitor);
          priv->monitor = NULL;
        }

      if (!filename || *filename == '\0')
        return;
      else
        priv->filename = g_strdup (filename);
    }
  else
    {
      if (!filename || *filename == '\0')
        priv->filename = get_default_filename ();
      else
        priv->filename = g_strdup (filename);
    }

  if (priv->filename != NULL)
    {
      file = g_file_new_for_path (priv->filename);

      error = NULL;
      priv->monitor = g_file_monitor_file (file, G_FILE_MONITOR_NONE, NULL, &error);
      if (error)
        {
          gchar *utf8 = g_filename_to_utf8 (priv->filename, -1, NULL, NULL, NULL);
          g_warning ("Unable to monitor '%s': %s\n"
                     "The GtkRecentManager will not update its contents "
                     "if the file is changed from other instances",
                     utf8 ? utf8 : "(invalid filename)",
                     error->message);
          g_free (utf8);
          g_error_free (error);
        }
      else
        g_signal_connect (priv->monitor, "changed",
                          G_CALLBACK (gtk_recent_manager_monitor_changed),
                          manager);

      g_object_unref (file);
    }

  build_recent_items_list (manager);
}

/* reads the recently used resources file and builds the items list.
 * we keep the items list inside the parser object, and build the
 * RecentInfo object only on user’s demand to avoid useless replication.
 * this function resets the dirty bit of the manager.
 */
static void
build_recent_items_list (GtkRecentManager *manager)
{
  GtkRecentManagerPrivate *priv = manager->priv;
  GError *read_error;
  gint size;

  if (!priv->recent_items)
    {
      priv->recent_items = g_bookmark_file_new ();
      priv->size = 0;
    }

  if (priv->filename != NULL)
    {
      /* the file exists, and it's valid (we hope); if not, destroy the container
       * object and hope for a better result when the next "changed" signal is
       * fired.
       */
      read_error = NULL;
      g_bookmark_file_load_from_file (priv->recent_items, priv->filename, &read_error);
      if (read_error)
        {
          /* if the file does not exist we just wait for the first write
           * operation on this recent manager instance, to avoid creating
           * empty files and leading to spurious file system events (Sabayon
           * will not be happy about those)
           */
          if (read_error->domain == G_FILE_ERROR &&
            read_error->code != G_FILE_ERROR_NOENT)
            {
              gchar *utf8 = g_filename_to_utf8 (priv->filename, -1, NULL, NULL, NULL);
              g_warning ("Attempting to read the recently used resources "
                         "file at '%s', but the parser failed: %s.",
                         utf8 ? utf8 : "(invalid filename)",
                         read_error->message);
              g_free (utf8);
            }

          g_bookmark_file_free (priv->recent_items);
          priv->recent_items = NULL;

          g_error_free (read_error);
        }
      else
        {
          size = g_bookmark_file_get_size (priv->recent_items);
          if (priv->size != size)
            {
              priv->size = size;

              g_object_notify (G_OBJECT (manager), "size");
            }
        }
    }

  priv->is_dirty = FALSE;
}


/********************
 * GtkRecentManager *
 ********************/


/**
 * gtk_recent_manager_new:
 *
 * Creates a new recent manager object. Recent manager objects are used to
 * handle the list of recently used resources. A #GtkRecentManager object
 * monitors the recently used resources list, and emits the “changed” signal
 * each time something inside the list changes.
 *
 * #GtkRecentManager objects are expensive: be sure to create them only when
 * needed. You should use gtk_recent_manager_get_default() instead.
 *
 * Returns: A newly created #GtkRecentManager object
 *
 * Since: 2.10
 */
GtkRecentManager *
gtk_recent_manager_new (void)
{
  return g_object_new (GTK_TYPE_RECENT_MANAGER, NULL);
}

/**
 * gtk_recent_manager_get_default:
 *
 * Gets a unique instance of #GtkRecentManager, that you can share
 * in your application without caring about memory management.
 *
 * Returns: (transfer none): A unique #GtkRecentManager. Do not ref or
 *   unref it.
 *
 * Since: 2.10
 */
GtkRecentManager *
gtk_recent_manager_get_default (void)
{
  if (G_UNLIKELY (!recent_manager_singleton))
    recent_manager_singleton = gtk_recent_manager_new ();

  return recent_manager_singleton;
}


static void
gtk_recent_manager_add_item_query_info (GObject      *source_object,
                                        GAsyncResult *res,
                                        gpointer      user_data)
{
  GFile *file = G_FILE (source_object);
  GtkRecentManager *manager = user_data;
  GtkRecentData recent_data;
  GFileInfo *file_info;
  gchar *uri, *basename;

  uri = g_file_get_uri (file);

  file_info = g_file_query_info_finish (file, res, NULL); /* NULL-GError */

  recent_data.display_name = NULL;
  recent_data.description = NULL;

  if (file_info)
    {
      gchar *content_type;

      content_type = g_file_info_get_attribute_as_string (file_info, G_FILE_ATTRIBUTE_STANDARD_FAST_CONTENT_TYPE);

      if (G_LIKELY (content_type))
        recent_data.mime_type = g_content_type_get_mime_type (content_type);
      else
        recent_data.mime_type = g_strdup (GTK_RECENT_DEFAULT_MIME);

      g_free (content_type);
      g_object_unref (file_info);
    }
  else
    {
      basename = g_file_get_basename (file);
      recent_data.mime_type = g_content_type_guess (basename, NULL, 0, NULL);
      g_free (basename);
    }

  recent_data.app_name = g_strdup (g_get_application_name ());
  recent_data.app_exec = g_strjoin (" ", g_get_prgname (), "%u", NULL);
  recent_data.groups = NULL;
  recent_data.is_private = FALSE;

  gdk_threads_enter ();

  /* Ignore return value, this can't fail anyway since all required
   * fields are set
   */
  gtk_recent_manager_add_full (manager, uri, &recent_data);

  manager->priv->is_dirty = TRUE;
  gtk_recent_manager_changed (manager);

  gdk_threads_leave ();

  g_free (recent_data.mime_type);
  g_free (recent_data.app_name);
  g_free (recent_data.app_exec);

  g_object_unref (manager);
  g_free (uri);
}

/**
 * gtk_recent_manager_add_item:
 * @manager: a #GtkRecentManager
 * @uri: a valid URI
 *
 * Adds a new resource, pointed by @uri, into the recently used
 * resources list.
 *
 * This function automatically retrieves some of the needed
 * metadata and setting other metadata to common default values;
 * it then feeds the data to gtk_recent_manager_add_full().
 *
 * See gtk_recent_manager_add_full() if you want to explicitly
 * define the metadata for the resource pointed by @uri.
 *
 * Returns: %TRUE if the new item was successfully added
 *   to the recently used resources list
 *
 * Since: 2.10
 */
gboolean
gtk_recent_manager_add_item (GtkRecentManager *manager,
                             const gchar      *uri)
{
  GFile* file;

  g_return_val_if_fail (GTK_IS_RECENT_MANAGER (manager), FALSE);
  g_return_val_if_fail (uri != NULL, FALSE);

  file = g_file_new_for_uri (uri);

  g_file_query_info_async (file,
                           G_FILE_ATTRIBUTE_STANDARD_FAST_CONTENT_TYPE,
                           G_PRIORITY_DEFAULT,
                           G_FILE_QUERY_INFO_NONE,
                           NULL,
                           gtk_recent_manager_add_item_query_info,
                           g_object_ref (manager));

  g_object_unref (file);

  return TRUE;
}

/**
 * gtk_recent_manager_add_full:
 * @manager: a #GtkRecentManager
 * @uri: a valid URI
 * @recent_data: metadata of the resource
 *
 * Adds a new resource, pointed by @uri, into the recently used
 * resources list, using the metadata specified inside the
 * #GtkRecentData-struct passed in @recent_data.
 *
 * The passed URI will be used to identify this resource inside the
 * list.
 *
 * In order to register the new recently used resource, metadata about
 * the resource must be passed as well as the URI; the metadata is
 * stored in a #GtkRecentData-struct, which must contain the MIME
 * type of the resource pointed by the URI; the name of the application
 * that is registering the item, and a command line to be used when
 * launching the item.
 *
 * Optionally, a #GtkRecentData-struct might contain a UTF-8 string
 * to be used when viewing the item instead of the last component of
 * the URI; a short description of the item; whether the item should
 * be considered private - that is, should be displayed only by the
 * applications that have registered it.
 *
 * Returns: %TRUE if the new item was successfully added to the
 *     recently used resources list, %FALSE otherwise
 *
 * Since: 2.10
 */
gboolean
gtk_recent_manager_add_full (GtkRecentManager    *manager,
                             const gchar         *uri,
                             const GtkRecentData *data)
{
  GtkRecentManagerPrivate *priv;
  GtkSettings *settings;
  gboolean enabled;

  g_return_val_if_fail (GTK_IS_RECENT_MANAGER (manager), FALSE);
  g_return_val_if_fail (uri != NULL, FALSE);
  g_return_val_if_fail (data != NULL, FALSE);

  /* sanity checks */
  if ((data->display_name) &&
      (!g_utf8_validate (data->display_name, -1, NULL)))
    {
      g_warning ("Attempting to add '%s' to the list of recently used "
                 "resources, but the display name is not a valid UTF-8 "
                 "encoded string",
                 uri);
      return FALSE;
    }

  if ((data->description) &&
      (!g_utf8_validate (data->description, -1, NULL)))
    {
      g_warning ("Attempting to add '%s' to the list of recently used "
                 "resources, but the description is not a valid UTF-8 "
                 "encoded string",
                 uri);
      return FALSE;
    }


  if (!data->mime_type)
    {
      g_warning ("Attempting to add '%s' to the list of recently used "
                 "resources, but no MIME type was defined",
                 uri);
      return FALSE;
    }

  if (!data->app_name)
    {
      g_warning ("Attempting to add '%s' to the list of recently used "
                 "resources, but no name of the application that is "
                 "registering it was defined",
                 uri);
      return FALSE;
    }

  if (!data->app_exec)
    {
      g_warning ("Attempting to add '%s' to the list of recently used "
                 "resources, but no command line for the application "
                 "that is registering it was defined",
                 uri);
      return FALSE;
    }

  settings = gtk_settings_get_default ();
  g_object_get (G_OBJECT (settings), "gtk-recent-files-enabled", &enabled, NULL);
  if (!enabled)
    return TRUE;

  priv = manager->priv;

  if (!priv->recent_items)
    {
      priv->recent_items = g_bookmark_file_new ();
      priv->size = 0;
    }

  if (data->display_name)
    g_bookmark_file_set_title (priv->recent_items, uri, data->display_name);

  if (data->description)
    g_bookmark_file_set_description (priv->recent_items, uri, data->description);

  g_bookmark_file_set_mime_type (priv->recent_items, uri, data->mime_type);

  if (data->groups && data->groups[0] != '\0')
    {
      gint j;

      for (j = 0; (data->groups)[j] != NULL; j++)
        g_bookmark_file_add_group (priv->recent_items, uri, (data->groups)[j]);
    }

  /* register the application; this will take care of updating the
   * registration count and time in case the application has
   * already registered the same document inside the list
   */
  g_bookmark_file_add_application (priv->recent_items, uri,
                                   data->app_name,
                                   data->app_exec);

  g_bookmark_file_set_is_private (priv->recent_items, uri,
                                  data->is_private);

  /* mark us as dirty, so that when emitting the "changed" signal we
   * will dump our changes
   */
  priv->is_dirty = TRUE;
  gtk_recent_manager_changed (manager);

  return TRUE;
}

/**
 * gtk_recent_manager_remove_item:
 * @manager: a #GtkRecentManager
 * @uri: the URI of the item you wish to remove
 * @error: (allow-none): return location for a #GError, or %NULL
 *
 * Removes a resource pointed by @uri from the recently used resources
 * list handled by a recent manager.
 *
 * Returns: %TRUE if the item pointed by @uri has been successfully
 *   removed by the recently used resources list, and %FALSE otherwise
 *
 * Since: 2.10
 */
gboolean
gtk_recent_manager_remove_item (GtkRecentManager  *manager,
                                const gchar       *uri,
                                GError           **error)
{
  GtkRecentManagerPrivate *priv;
  GError *remove_error = NULL;

  g_return_val_if_fail (GTK_IS_RECENT_MANAGER (manager), FALSE);
  g_return_val_if_fail (uri != NULL, FALSE);
  g_return_val_if_fail (error == NULL || *error == NULL, FALSE);

  priv = manager->priv;

  if (!priv->recent_items)
    {
      priv->recent_items = g_bookmark_file_new ();
      priv->size = 0;

      g_set_error (error, GTK_RECENT_MANAGER_ERROR,
                   GTK_RECENT_MANAGER_ERROR_NOT_FOUND,
                   _("Unable to find an item with URI '%s'"),
                   uri);

      return FALSE;
    }

  g_bookmark_file_remove_item (priv->recent_items, uri, &remove_error);
  if (remove_error)
    {
      g_error_free (remove_error);

      g_set_error (error, GTK_RECENT_MANAGER_ERROR,
                   GTK_RECENT_MANAGER_ERROR_NOT_FOUND,
                   _("Unable to find an item with URI '%s'"),
                   uri);

      return FALSE;
    }

  priv->is_dirty = TRUE;
  gtk_recent_manager_changed (manager);

  return TRUE;
}

/**
 * gtk_recent_manager_has_item:
 * @manager: a #GtkRecentManager
 * @uri: a URI
 *
 * Checks whether there is a recently used resource registered
 * with @uri inside the recent manager.
 *
 * Returns: %TRUE if the resource was found, %FALSE otherwise
 *
 * Since: 2.10
 */
gboolean
gtk_recent_manager_has_item (GtkRecentManager *manager,
                             const gchar      *uri)
{
  GtkRecentManagerPrivate *priv;

  g_return_val_if_fail (GTK_IS_RECENT_MANAGER (manager), FALSE);
  g_return_val_if_fail (uri != NULL, FALSE);

  priv = manager->priv;
  g_return_val_if_fail (priv->recent_items != NULL, FALSE);

  return g_bookmark_file_has_item (priv->recent_items, uri);
}

static void
build_recent_info (GBookmarkFile *bookmarks,
                   GtkRecentInfo *info)
{
  gchar **apps, **groups;
  gsize apps_len, groups_len, i;

  g_assert (bookmarks != NULL);
  g_assert (info != NULL);

  info->display_name = g_bookmark_file_get_title (bookmarks, info->uri, NULL);
  info->description = g_bookmark_file_get_description (bookmarks, info->uri, NULL);
  info->mime_type = g_bookmark_file_get_mime_type (bookmarks, info->uri, NULL);

  info->is_private = g_bookmark_file_get_is_private (bookmarks, info->uri, NULL);

  info->added = g_bookmark_file_get_added (bookmarks, info->uri, NULL);
  info->modified = g_bookmark_file_get_modified (bookmarks, info->uri, NULL);
  info->visited = g_bookmark_file_get_visited (bookmarks, info->uri, NULL);

  groups = g_bookmark_file_get_groups (bookmarks, info->uri, &groups_len, NULL);
  for (i = 0; i < groups_len; i++)
    {
      gchar *group_name = g_strdup (groups[i]);

      info->groups = g_slist_append (info->groups, group_name);
    }

  g_strfreev (groups);

  apps = g_bookmark_file_get_applications (bookmarks, info->uri, &apps_len, NULL);
  for (i = 0; i < apps_len; i++)
    {
      gchar *app_name, *app_exec;
      guint count;
      time_t stamp;
      RecentAppInfo *app_info;
      gboolean res;

      app_name = apps[i];

      res = g_bookmark_file_get_app_info (bookmarks, info->uri, app_name,
                                          &app_exec,
                                          &count,
                                          &stamp,
                                          NULL);
      if (!res)
        continue;

      app_info = recent_app_info_new (app_name);
      app_info->exec = app_exec;
      app_info->count = count;
      app_info->stamp = stamp;

      info->applications = g_slist_prepend (info->applications, app_info);
      g_hash_table_replace (info->apps_lookup, app_info->name, app_info);
    }

  g_strfreev (apps);
}

/**
 * gtk_recent_manager_lookup_item:
 * @manager: a #GtkRecentManager
 * @uri: a URI
 * @error: (allow-none): a return location for a #GError, or %NULL
 *
 * Searches for a URI inside the recently used resources list, and
 * returns a #GtkRecentInfo-struct containing informations about the resource
 * like its MIME type, or its display name.
 *
 * Returns: (nullable): a #GtkRecentInfo-struct containing information
 *   about the resource pointed by @uri, or %NULL if the URI was
 *   not registered in the recently used resources list. Free with
 *   gtk_recent_info_unref().
 *
 * Since: 2.10
 */
GtkRecentInfo *
gtk_recent_manager_lookup_item (GtkRecentManager  *manager,
                                const gchar       *uri,
                                GError           **error)
{
  GtkRecentManagerPrivate *priv;
  GtkRecentInfo *info = NULL;

  g_return_val_if_fail (GTK_IS_RECENT_MANAGER (manager), NULL);
  g_return_val_if_fail (uri != NULL, NULL);
  g_return_val_if_fail (error == NULL || *error == NULL, NULL);

  priv = manager->priv;
  if (!priv->recent_items)
    {
      priv->recent_items = g_bookmark_file_new ();
      priv->size = 0;

      g_set_error (error, GTK_RECENT_MANAGER_ERROR,
                   GTK_RECENT_MANAGER_ERROR_NOT_FOUND,
                   _("Unable to find an item with URI '%s'"),
                   uri);

      return NULL;
    }

  if (!g_bookmark_file_has_item (priv->recent_items, uri))
    {
      g_set_error (error, GTK_RECENT_MANAGER_ERROR,
                   GTK_RECENT_MANAGER_ERROR_NOT_FOUND,
                   _("Unable to find an item with URI '%s'"),
                   uri);
      return NULL;
    }

  info = gtk_recent_info_new (uri);
  g_return_val_if_fail (info != NULL, NULL);

  /* fill the RecentInfo structure with the data retrieved by our
   * parser object from the storage file
   */
  build_recent_info (priv->recent_items, info);

  return info;
}

/**
 * gtk_recent_manager_move_item:
 * @manager: a #GtkRecentManager
 * @uri: the URI of a recently used resource
 * @new_uri: (allow-none): the new URI of the recently used resource, or
 *    %NULL to remove the item pointed by @uri in the list
 * @error: (allow-none): a return location for a #GError, or %NULL
 *
 * Changes the location of a recently used resource from @uri to @new_uri.
 *
 * Please note that this function will not affect the resource pointed
 * by the URIs, but only the URI used in the recently used resources list.
 *
 * Returns: %TRUE on success
 *
 * Since: 2.10
 */
gboolean
gtk_recent_manager_move_item (GtkRecentManager  *recent_manager,
                              const gchar       *uri,
                              const gchar       *new_uri,
                              GError           **error)
{
  GtkRecentManagerPrivate *priv;
  GError *move_error;

  g_return_val_if_fail (GTK_IS_RECENT_MANAGER (recent_manager), FALSE);
  g_return_val_if_fail (uri != NULL, FALSE);
  g_return_val_if_fail (error == NULL || *error == NULL, FALSE);

  priv = recent_manager->priv;

  if (!priv->recent_items)
    {
      g_set_error (error, GTK_RECENT_MANAGER_ERROR,
                   GTK_RECENT_MANAGER_ERROR_NOT_FOUND,
                   _("Unable to find an item with URI '%s'"),
                   uri);
      return FALSE;
    }

  if (!g_bookmark_file_has_item (priv->recent_items, uri))
    {
      g_set_error (error, GTK_RECENT_MANAGER_ERROR,
                   GTK_RECENT_MANAGER_ERROR_NOT_FOUND,
                   _("Unable to find an item with URI '%s'"),
                   uri);
      return FALSE;
    }

  move_error = NULL;
  if (!g_bookmark_file_move_item (priv->recent_items,
                                  uri,
                                  new_uri,
                                  &move_error))
    {
      g_error_free (move_error);

      g_set_error (error, GTK_RECENT_MANAGER_ERROR,
                   GTK_RECENT_MANAGER_ERROR_UNKNOWN,
                   _("Unable to move the item with URI '%s' to '%s'"),
                   uri, new_uri);
      return FALSE;
    }

  priv->is_dirty = TRUE;
  gtk_recent_manager_changed (recent_manager);

  return TRUE;
}

/**
 * gtk_recent_manager_get_items:
 * @manager: a #GtkRecentManager
 *
 * Gets the list of recently used resources.
 *
 * Returns: (element-type GtkRecentInfo) (transfer full): a list of
 *   newly allocated #GtkRecentInfo objects. Use
 *   gtk_recent_info_unref() on each item inside the list, and then
 *   free the list itself using g_list_free().
 *
 * Since: 2.10
 */
GList *
gtk_recent_manager_get_items (GtkRecentManager *manager)
{
  GtkRecentManagerPrivate *priv;
  GList *retval = NULL;
  gchar **uris;
  gsize uris_len, i;

  g_return_val_if_fail (GTK_IS_RECENT_MANAGER (manager), NULL);

  priv = manager->priv;
  if (!priv->recent_items)
    return NULL;

  uris = g_bookmark_file_get_uris (priv->recent_items, &uris_len);
  for (i = 0; i < uris_len; i++)
    {
      GtkRecentInfo *info;

      info = gtk_recent_info_new (uris[i]);
      build_recent_info (priv->recent_items, info);

      retval = g_list_prepend (retval, info);
    }

  g_strfreev (uris);

  return retval;
}

static void
purge_recent_items_list (GtkRecentManager  *manager,
                         GError           **error)
{
  GtkRecentManagerPrivate *priv = manager->priv;

  if (priv->recent_items == NULL)
    return;

  g_bookmark_file_free (priv->recent_items);
  priv->recent_items = g_bookmark_file_new ();
  priv->size = 0;

  /* emit the changed signal, to ensure that the purge is written */
  priv->is_dirty = TRUE;
  gtk_recent_manager_changed (manager);
}

/**
 * gtk_recent_manager_purge_items:
 * @manager: a #GtkRecentManager
 * @error: (allow-none): a return location for a #GError, or %NULL
 *
 * Purges every item from the recently used resources list.
 *
 * Returns: the number of items that have been removed from the
 *   recently used resources list
 *
 * Since: 2.10
 */
gint
gtk_recent_manager_purge_items (GtkRecentManager  *manager,
                                GError           **error)
{
  GtkRecentManagerPrivate *priv;
  gint count, purged;

  g_return_val_if_fail (GTK_IS_RECENT_MANAGER (manager), -1);

  priv = manager->priv;
  if (!priv->recent_items)
    return 0;

  count = g_bookmark_file_get_size (priv->recent_items);
  if (!count)
    return 0;

  purge_recent_items_list (manager, error);

  purged = count - g_bookmark_file_get_size (priv->recent_items);

  return purged;
}

static gboolean
emit_manager_changed (gpointer data)
{
  GtkRecentManager *manager = data;

  manager->priv->changed_age = 0;
  manager->priv->changed_timeout = 0;

  g_signal_emit (manager, signal_changed, 0);

  return FALSE;
}

static void
gtk_recent_manager_changed (GtkRecentManager *manager)
{
  /* coalesce consecutive changes
   *
   * we schedule a write in 250 msecs immediately; if we get more than one
   * request per millisecond before the timeout has a chance to run, we
   * schedule an emission immediately.
   */
  if (manager->priv->changed_timeout == 0)
    {
      manager->priv->changed_timeout = gdk_threads_add_timeout (250, emit_manager_changed, manager);
      g_source_set_name_by_id (manager->priv->changed_timeout, "[gtk+] emit_manager_changed");
    }
  else
    {
      manager->priv->changed_age += 1;

      if (manager->priv->changed_age > 250)
        {
          g_source_remove (manager->priv->changed_timeout);
          g_signal_emit (manager, signal_changed, 0);

          manager->priv->changed_age = 0;
          manager->priv->changed_timeout = 0;
        }
    }
}

static void
gtk_recent_manager_clamp_to_age (GtkRecentManager *manager,
                                 gint              age)
{
  GtkRecentManagerPrivate *priv = manager->priv;
  gchar **uris;
  gsize n_uris, i;
  time_t now;

  if (G_UNLIKELY (!priv->recent_items))
    return;

  now = time (NULL);

  uris = g_bookmark_file_get_uris (priv->recent_items, &n_uris);

  for (i = 0; i < n_uris; i++)
    {
      const gchar *uri = uris[i];
      time_t modified;
      gint item_age;

      modified = g_bookmark_file_get_modified (priv->recent_items, uri, NULL);
      item_age = (gint) ((now - modified) / (60 * 60 * 24));
      if (item_age > age)
        g_bookmark_file_remove_item (priv->recent_items, uri, NULL);
    }

  g_strfreev (uris);
}

/*****************
 * GtkRecentInfo *
 *****************/

G_DEFINE_BOXED_TYPE (GtkRecentInfo, gtk_recent_info,
                     gtk_recent_info_ref,
                     gtk_recent_info_unref)

static GtkRecentInfo *
gtk_recent_info_new (const gchar *uri)
{
  GtkRecentInfo *info;

  g_assert (uri != NULL);

  info = g_new0 (GtkRecentInfo, 1);
  info->uri = g_strdup (uri);

  info->applications = NULL;
  info->apps_lookup = g_hash_table_new (g_str_hash, g_str_equal);

  info->groups = NULL;

  info->ref_count = 1;

  return info;
}

static void
gtk_recent_info_free (GtkRecentInfo *recent_info)
{
  if (!recent_info)
    return;

  g_free (recent_info->uri);
  g_free (recent_info->display_name);
  g_free (recent_info->description);
  g_free (recent_info->mime_type);

  g_slist_free_full (recent_info->applications, (GDestroyNotify)recent_app_info_free);

  if (recent_info->apps_lookup)
    g_hash_table_destroy (recent_info->apps_lookup);

  g_slist_free_full (recent_info->groups, g_free);

  if (recent_info->icon)
    g_object_unref (recent_info->icon);

  g_free (recent_info);
}

/**
 * gtk_recent_info_ref:
 * @info: a #GtkRecentInfo
 *
 * Increases the reference count of @recent_info by one.
 *
 * Returns: the recent info object with its reference count
 *     increased by one
 *
 * Since: 2.10
 */
GtkRecentInfo *
gtk_recent_info_ref (GtkRecentInfo *info)
{
  g_return_val_if_fail (info != NULL, NULL);
  g_return_val_if_fail (info->ref_count > 0, NULL);

  info->ref_count += 1;

  return info;
}

/**
 * gtk_recent_info_unref:
 * @info: a #GtkRecentInfo
 *
 * Decreases the reference count of @info by one. If the reference
 * count reaches zero, @info is deallocated, and the memory freed.
 *
 * Since: 2.10
 */
void
gtk_recent_info_unref (GtkRecentInfo *info)
{
  g_return_if_fail (info != NULL);
  g_return_if_fail (info->ref_count > 0);

  info->ref_count -= 1;

  if (info->ref_count == 0)
    gtk_recent_info_free (info);
}

/**
 * gtk_recent_info_get_uri:
 * @info: a #GtkRecentInfo
 *
 * Gets the URI of the resource.
 *
 * Returns: the URI of the resource. The returned string is
 *   owned by the recent manager, and should not be freed.
 *
 * Since: 2.10
 */
const gchar *
gtk_recent_info_get_uri (GtkRecentInfo *info)
{
  g_return_val_if_fail (info != NULL, NULL);

  return info->uri;
}

/**
 * gtk_recent_info_get_display_name:
 * @info: a #GtkRecentInfo
 *
 * Gets the name of the resource. If none has been defined, the basename
 * of the resource is obtained.
 *
 * Returns: the display name of the resource. The returned string
 *   is owned by the recent manager, and should not be freed.
 *
 * Since: 2.10
 */
const gchar *
gtk_recent_info_get_display_name (GtkRecentInfo *info)
{
  g_return_val_if_fail (info != NULL, NULL);

  if (!info->display_name)
    info->display_name = gtk_recent_info_get_short_name (info);

  return info->display_name;
}

/**
 * gtk_recent_info_get_description:
 * @info: a #GtkRecentInfo
 *
 * Gets the (short) description of the resource.
 *
 * Returns: the description of the resource. The returned string
 *   is owned by the recent manager, and should not be freed.
 *
 * Since: 2.10
 **/
const gchar *
gtk_recent_info_get_description (GtkRecentInfo *info)
{
  g_return_val_if_fail (info != NULL, NULL);

  return info->description;
}

/**
 * gtk_recent_info_get_mime_type:
 * @info: a #GtkRecentInfo
 *
 * Gets the MIME type of the resource.
 *
 * Returns: the MIME type of the resource. The returned string
 *   is owned by the recent manager, and should not be freed.
 *
 * Since: 2.10
 */
const gchar *
gtk_recent_info_get_mime_type (GtkRecentInfo *info)
{
  g_return_val_if_fail (info != NULL, NULL);

  if (!info->mime_type)
    info->mime_type = g_strdup (GTK_RECENT_DEFAULT_MIME);

  return info->mime_type;
}

/**
 * gtk_recent_info_get_added:
 * @info: a #GtkRecentInfo
 *
 * Gets the timestamp (seconds from system’s Epoch) when the resource
 * was added to the recently used resources list.
 *
 * Returns: the number of seconds elapsed from system’s Epoch when
 *   the resource was added to the list, or -1 on failure.
 *
 * Since: 2.10
 */
time_t
gtk_recent_info_get_added (GtkRecentInfo *info)
{
  g_return_val_if_fail (info != NULL, (time_t) -1);

  return info->added;
}

/**
 * gtk_recent_info_get_modified:
 * @info: a #GtkRecentInfo
 *
 * Gets the timestamp (seconds from system’s Epoch) when the meta-data
 * for the resource was last modified.
 *
 * Returns: the number of seconds elapsed from system’s Epoch when
 *   the resource was last modified, or -1 on failure.
 *
 * Since: 2.10
 */
time_t
gtk_recent_info_get_modified (GtkRecentInfo *info)
{
  g_return_val_if_fail (info != NULL, (time_t) -1);

  return info->modified;
}

/**
 * gtk_recent_info_get_visited:
 * @info: a #GtkRecentInfo
 *
 * Gets the timestamp (seconds from system’s Epoch) when the meta-data
 * for the resource was last visited.
 *
 * Returns: the number of seconds elapsed from system’s Epoch when
 *   the resource was last visited, or -1 on failure.
 *
 * Since: 2.10
 */
time_t
gtk_recent_info_get_visited (GtkRecentInfo *info)
{
  g_return_val_if_fail (info != NULL, (time_t) -1);

  return info->visited;
}

/**
 * gtk_recent_info_get_private_hint:
 * @info: a #GtkRecentInfo
 *
 * Gets the value of the “private” flag. Resources in the recently used
 * list that have this flag set to %TRUE should only be displayed by the
 * applications that have registered them.
 *
 * Returns: %TRUE if the private flag was found, %FALSE otherwise
 *
 * Since: 2.10
 */
gboolean
gtk_recent_info_get_private_hint (GtkRecentInfo *info)
{
  g_return_val_if_fail (info != NULL, FALSE);

  return info->is_private;
}


static RecentAppInfo *
recent_app_info_new (const gchar *app_name)
{
  RecentAppInfo *app_info;

  g_assert (app_name != NULL);

  app_info = g_slice_new0 (RecentAppInfo);
  app_info->name = g_strdup (app_name);
  app_info->exec = NULL;
  app_info->count = 1;
  app_info->stamp = 0;

  return app_info;
}

static void
recent_app_info_free (RecentAppInfo *app_info)
{
  if (!app_info)
    return;

  g_free (app_info->name);
  g_free (app_info->exec);

  g_slice_free (RecentAppInfo, app_info);
}

/**
 * gtk_recent_info_get_application_info:
 * @info: a #GtkRecentInfo
 * @app_name: the name of the application that has registered this item
 * @app_exec: (transfer none) (out): return location for the string containing
 *    the command line
 * @count: (out): return location for the number of times this item was registered
 * @time_: (out): return location for the timestamp this item was last registered
 *    for this application
 *
 * Gets the data regarding the application that has registered the resource
 * pointed by @info.
 *
 * If the command line contains any escape characters defined inside the
 * storage specification, they will be expanded.
 *
 * Returns: %TRUE if an application with @app_name has registered this
 *   resource inside the recently used list, or %FALSE otherwise. The
 *   @app_exec string is owned by the #GtkRecentInfo and should not be
 *   modified or freed
 *
 * Since: 2.10
 */
gboolean
gtk_recent_info_get_application_info (GtkRecentInfo  *info,
                                      const gchar    *app_name,
                                      const gchar   **app_exec,
                                      guint          *count,
                                      time_t         *time_)
{
  RecentAppInfo *ai;

  g_return_val_if_fail (info != NULL, FALSE);
  g_return_val_if_fail (app_name != NULL, FALSE);

  ai = (RecentAppInfo *) g_hash_table_lookup (info->apps_lookup,
                                              app_name);
  if (!ai)
    {
      g_warning ("No registered application with name '%s' "
                 "for item with URI '%s' found",
                 app_name,
                 info->uri);
      return FALSE;
    }

  if (app_exec)
    *app_exec = ai->exec;

  if (count)
    *count = ai->count;

  if (time_)
    *time_ = ai->stamp;

  return TRUE;
}

/**
 * gtk_recent_info_get_applications:
 * @info: a #GtkRecentInfo
 * @length: (out) (allow-none): return location for the length of the returned list
 *
 * Retrieves the list of applications that have registered this resource.
 *
 * Returns: (array length=length zero-terminated=1) (transfer full):
 *     a newly allocated %NULL-terminated array of strings.
 *     Use g_strfreev() to free it.
 *
 * Since: 2.10
 */
gchar **
gtk_recent_info_get_applications (GtkRecentInfo *info,
                                  gsize         *length)
{
  GSList *l;
  gchar **retval;
  gsize n_apps, i;

  g_return_val_if_fail (info != NULL, NULL);

  if (!info->applications)
    {
      if (length)
        *length = 0;

      return NULL;
    }

  n_apps = g_slist_length (info->applications);

  retval = g_new0 (gchar *, n_apps + 1);

  for (l = info->applications, i = 0;
       l != NULL;
       l = l->next)
    {
      RecentAppInfo *ai = (RecentAppInfo *) l->data;

      g_assert (ai != NULL);

      retval[i++] = g_strdup (ai->name);
    }
  retval[i] = NULL;

  if (length)
    *length = i;

  return retval;
}

/**
 * gtk_recent_info_has_application:
 * @info: a #GtkRecentInfo
 * @app_name: a string containing an application name
 *
 * Checks whether an application registered this resource using @app_name.
 *
 * Returns: %TRUE if an application with name @app_name was found,
 *   %FALSE otherwise
 *
 * Since: 2.10
 */
gboolean
gtk_recent_info_has_application (GtkRecentInfo *info,
                                 const gchar   *app_name)
{
  g_return_val_if_fail (info != NULL, FALSE);
  g_return_val_if_fail (app_name != NULL, FALSE);

  return (NULL != g_hash_table_lookup (info->apps_lookup, app_name));
}

/**
 * gtk_recent_info_last_application:
 * @info: a #GtkRecentInfo
 *
 * Gets the name of the last application that have registered the
 * recently used resource represented by @info.
 *
 * Returns: an application name. Use g_free() to free it.
 *
 * Since: 2.10
 */
gchar *
gtk_recent_info_last_application (GtkRecentInfo *info)
{
  GSList *l;
  time_t last_stamp = (time_t) -1;
  gchar *name = NULL;

  g_return_val_if_fail (info != NULL, NULL);

  for (l = info->applications; l != NULL; l = l->next)
    {
      RecentAppInfo *ai = (RecentAppInfo *) l->data;

      if (ai->stamp > last_stamp)
        {
          name = ai->name;
          last_stamp = ai->stamp;
        }
    }

  return g_strdup (name);
}

static GdkPixbuf *
get_icon_for_mime_type (const gchar *mime_type,
                        gint         pixel_size)
{
  GtkIconTheme *icon_theme;
  char *content_type;
  GIcon *icon;
  GtkIconInfo *info;
  GdkPixbuf *pixbuf;

  icon_theme = gtk_icon_theme_get_default ();

  content_type = g_content_type_from_mime_type (mime_type);

  if (!content_type)
    return NULL;

  icon = g_content_type_get_icon (content_type);
  info = gtk_icon_theme_lookup_by_gicon (icon_theme,
                                         icon,
                                         pixel_size,
                                         GTK_ICON_LOOKUP_USE_BUILTIN);
  g_free (content_type);
  g_object_unref (icon);

  if (!info)
    return NULL;

  pixbuf = gtk_icon_info_load_icon (info, NULL);
  g_object_unref (info);

  return pixbuf;
}

static GdkPixbuf *
get_icon_fallback (const gchar *icon_name,
                   gint         size)
{
  GtkIconTheme *icon_theme;
  GdkPixbuf *retval;

  icon_theme = gtk_icon_theme_get_default ();

  retval = gtk_icon_theme_load_icon (icon_theme, icon_name,
                                     size,
                                     GTK_ICON_LOOKUP_USE_BUILTIN,
                                     NULL);
  g_assert (retval != NULL);

  return retval;
}

/**
 * gtk_recent_info_get_icon:
 * @info: a #GtkRecentInfo
 * @size: the size of the icon in pixels
 *
 * Retrieves the icon of size @size associated to the resource MIME type.
 *
 * Returns: (transfer full): a #GdkPixbuf containing the icon,
 *     or %NULL. Use g_object_unref() when finished using the icon.
 *
 * Since: 2.10
 */
GdkPixbuf *
gtk_recent_info_get_icon (GtkRecentInfo *info,
                          gint           size)
{
  GdkPixbuf *retval = NULL;

  g_return_val_if_fail (info != NULL, NULL);

  if (info->mime_type)
    retval = get_icon_for_mime_type (info->mime_type, size);

  /* this function should never fail */
  if (!retval)
    {
      if (info->mime_type &&
          strcmp (info->mime_type, "x-directory/normal") == 0)
        retval = get_icon_fallback ("folder", size);
      else
        retval = get_icon_fallback ("text-x-generic", size);
    }

  return retval;
}

/**
 * gtk_recent_info_get_gicon:
 * @info: a #GtkRecentInfo
 *
 * Retrieves the icon associated to the resource MIME type.
 *
 * Returns: (transfer full): a #GIcon containing the icon, or %NULL.
 *   Use g_object_unref() when finished using the icon
 *
 * Since: 2.22
 */
GIcon *
gtk_recent_info_get_gicon (GtkRecentInfo *info)
{
  GIcon *icon = NULL;
  gchar *content_type;

  g_return_val_if_fail (info != NULL, NULL);

  if (info->mime_type != NULL &&
      (content_type = g_content_type_from_mime_type (info->mime_type)) != NULL)
    {
      icon = g_content_type_get_icon (content_type);
      g_free (content_type);
    }

  return icon;
}

/**
 * gtk_recent_info_is_local:
 * @info: a #GtkRecentInfo
 *
 * Checks whether the resource is local or not by looking at the
 * scheme of its URI.
 *
 * Returns: %TRUE if the resource is local
 *
 * Since: 2.10
 */
gboolean
gtk_recent_info_is_local (GtkRecentInfo *info)
{
  g_return_val_if_fail (info != NULL, FALSE);

  return has_case_prefix (info->uri, "file:/");
}

/**
 * gtk_recent_info_exists:
 * @info: a #GtkRecentInfo
 *
 * Checks whether the resource pointed by @info still exists.
 * At the moment this check is done only on resources pointing
 * to local files.
 *
 * Returns: %TRUE if the resource exists
 *
 * Since: 2.10
 */
gboolean
gtk_recent_info_exists (GtkRecentInfo *info)
{
  gchar *filename;
  GStatBuf stat_buf;
  gboolean retval = FALSE;

  g_return_val_if_fail (info != NULL, FALSE);

  /* we guarantee only local resources */
  if (!gtk_recent_info_is_local (info))
    return FALSE;

  filename = g_filename_from_uri (info->uri, NULL, NULL);
  if (filename)
    {
      if (g_stat (filename, &stat_buf) == 0)
        retval = TRUE;

      g_free (filename);
    }

  return retval;
}

/**
 * gtk_recent_info_match:
 * @info_a: a #GtkRecentInfo
 * @info_b: a #GtkRecentInfo
 *
 * Checks whether two #GtkRecentInfo-struct point to the same
 * resource.
 *
 * Returns: %TRUE if both #GtkRecentInfo-struct point to the same
 *   resource, %FALSE otherwise
 *
 * Since: 2.10
 */
gboolean
gtk_recent_info_match (GtkRecentInfo *info_a,
                       GtkRecentInfo *info_b)
{
  g_return_val_if_fail (info_a != NULL, FALSE);
  g_return_val_if_fail (info_b != NULL, FALSE);

  return (0 == strcmp (info_a->uri, info_b->uri));
}

/* taken from gnome-vfs-uri.c */
static const gchar *
get_method_string (const gchar  *substring,
                   gchar       **method_string)
{
  const gchar *p;
  char *method;

  for (p = substring;
       g_ascii_isalnum (*p) || *p == '+' || *p == '-' || *p == '.';
       p++)
    ;

  if (*p == ':'
#ifdef G_OS_WIN32
                &&
      !(p == substring + 1 && g_ascii_isalpha (*substring))
#endif
                                                           )
    {
      /* Found toplevel method specification.  */
      method = g_strndup (substring, p - substring);
      *method_string = g_ascii_strdown (method, -1);
      g_free (method);
      p++;
    }
  else
    {
      *method_string = g_strdup ("file");
      p = substring;
    }

  return p;
}

/* Stolen from gnome_vfs_make_valid_utf8() */
static char *
make_valid_utf8 (const char *name)
{
  GString *string;
  const char *remainder, *invalid;
  int remaining_bytes, valid_bytes;

  string = NULL;
  remainder = name;
  remaining_bytes = name ? strlen (name) : 0;

  while (remaining_bytes != 0)
    {
      if (g_utf8_validate (remainder, remaining_bytes, &invalid))
        break;

      valid_bytes = invalid - remainder;

      if (string == NULL)
        string = g_string_sized_new (remaining_bytes);

      g_string_append_len (string, remainder, valid_bytes);
      g_string_append_c (string, '?');

      remaining_bytes -= valid_bytes + 1;
      remainder = invalid + 1;
    }

  if (string == NULL)
    return g_strdup (name);

  g_string_append (string, remainder);
  g_assert (g_utf8_validate (string->str, -1, NULL));

  return g_string_free (string, FALSE);
}

static gchar *
get_uri_shortname_for_display (const gchar *uri)
{
  gchar *name = NULL;
  gboolean validated = FALSE;

  if (has_case_prefix (uri, "file:/"))
    {
      gchar *local_file;

      local_file = g_filename_from_uri (uri, NULL, NULL);

      if (local_file)
        {
          name = g_filename_display_basename (local_file);
          validated = TRUE;
        }

      g_free (local_file);
    }

  if (!name)
    {
      gchar *method;
      gchar *local_file;
      const gchar *rest;

      rest = get_method_string (uri, &method);
      local_file = g_filename_display_basename (rest);

      name = g_strconcat (method, ": ", local_file, NULL);

      g_free (local_file);
      g_free (method);
    }

  g_assert (name != NULL);

  if (!validated && !g_utf8_validate (name, -1, NULL))
    {
      gchar *utf8_name;

      utf8_name = make_valid_utf8 (name);
      g_free (name);

      name = utf8_name;
    }

  return name;
}

/**
 * gtk_recent_info_get_short_name:
 * @info: an #GtkRecentInfo
 *
 * Computes a valid UTF-8 string that can be used as the
 * name of the item in a menu or list. For example, calling
 * this function on an item that refers to
 * “file:///foo/bar.txt” will yield “bar.txt”.
 *
 * Returns: A newly-allocated string in UTF-8 encoding
 *   free it with g_free()
 *
 * Since: 2.10
 */
gchar *
gtk_recent_info_get_short_name (GtkRecentInfo *info)
{
  gchar *short_name;

  g_return_val_if_fail (info != NULL, NULL);

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

  short_name = get_uri_shortname_for_display (info->uri);

  return short_name;
}

/**
 * gtk_recent_info_get_uri_display:
 * @info: a #GtkRecentInfo
 *
 * Gets a displayable version of the resource’s URI. If the resource
 * is local, it returns a local path; if the resource is not local,
 * it returns the UTF-8 encoded content of gtk_recent_info_get_uri().
 *
 * Returns: a newly allocated UTF-8 string containing the
 *   resource’s URI or %NULL. Use g_free() when done using it.
 *
 * Since: 2.10
 */
gchar *
gtk_recent_info_get_uri_display (GtkRecentInfo *info)
{
  gchar *retval;

  g_return_val_if_fail (info != NULL, NULL);

  retval = NULL;
  if (gtk_recent_info_is_local (info))
    {
      gchar *filename;

      filename = g_filename_from_uri (info->uri, NULL, NULL);
      if (!filename)
        return NULL;

      retval = g_filename_to_utf8 (filename, -1, NULL, NULL, NULL);
      g_free (filename);
    }
  else
    {
      retval = make_valid_utf8 (info->uri);
    }

  return retval;
}

/**
 * gtk_recent_info_get_age:
 * @info: a #GtkRecentInfo
 *
 * Gets the number of days elapsed since the last update
 * of the resource pointed by @info.
 *
 * Returns: a positive integer containing the number of days
 *   elapsed since the time this resource was last modified
 *
 * Since: 2.10
 */
gint
gtk_recent_info_get_age (GtkRecentInfo *info)
{
  time_t now, delta;
  gint retval;

  g_return_val_if_fail (info != NULL, -1);

  now = time (NULL);

  delta = now - info->modified;

  retval = (gint) (delta / (60 * 60 * 24));

  return retval;
}

/**
 * gtk_recent_info_get_groups:
 * @info: a #GtkRecentInfo
 * @length: (out) (allow-none): return location for the number of groups returned
 *
 * Returns all groups registered for the recently used item @info.
 * The array of returned group names will be %NULL terminated, so
 * length might optionally be %NULL.
 *
 * Returns: (array length=length zero-terminated=1) (transfer full):
 *   a newly allocated %NULL terminated array of strings.
 *   Use g_strfreev() to free it.
 *
 * Since: 2.10
 */
gchar **
gtk_recent_info_get_groups (GtkRecentInfo *info,
                            gsize         *length)
{
  GSList *l;
  gchar **retval;
  gsize n_groups, i;

  g_return_val_if_fail (info != NULL, NULL);

  if (!info->groups)
    {
      if (length)
        *length = 0;

      return NULL;
    }

  n_groups = g_slist_length (info->groups);

  retval = g_new0 (gchar *, n_groups + 1);

  for (l = info->groups, i = 0;
       l != NULL;
       l = l->next)
    {
      gchar *group_name = (gchar *) l->data;

      g_assert (group_name != NULL);

      retval[i++] = g_strdup (group_name);
    }
  retval[i] = NULL;

  if (length)
    *length = i;

  return retval;
}

/**
 * gtk_recent_info_has_group:
 * @info: a #GtkRecentInfo
 * @group_name: name of a group
 *
 * Checks whether @group_name appears inside the groups
 * registered for the recently used item @info.
 *
 * Returns: %TRUE if the group was found
 *
 * Since: 2.10
 */
gboolean
gtk_recent_info_has_group (GtkRecentInfo *info,
                           const gchar   *group_name)
{
  GSList *l;

  g_return_val_if_fail (info != NULL, FALSE);
  g_return_val_if_fail (group_name != NULL, FALSE);

  if (!info->groups)
    return FALSE;

  for (l = info->groups; l != NULL; l = l->next)
    {
      gchar *g = (gchar *) l->data;

      if (strcmp (g, group_name) == 0)
        return TRUE;
    }

  return FALSE;
}

/**
 * gtk_recent_info_create_app_info:
 * @info: a #GtkRecentInfo
 * @app_name: (allow-none): the name of the application that should
 *   be mapped to a #GAppInfo; if %NULL is used then the default
 *   application for the MIME type is used
 * @error: (allow-none): return location for a #GError, or %NULL
 *
 * Creates a #GAppInfo for the specified #GtkRecentInfo
 *
 * Returns: (transfer full): the newly created #GAppInfo, or %NULL.
 *   In case of error, @error will be set either with a
 *   %GTK_RECENT_MANAGER_ERROR or a %G_IO_ERROR
 */
GAppInfo *
gtk_recent_info_create_app_info (GtkRecentInfo  *info,
                                 const gchar    *app_name,
                                 GError        **error)
{
  RecentAppInfo *ai;
  GAppInfo *app_info;
  GError *internal_error = NULL;

  g_return_val_if_fail (info != NULL, NULL);

  if (app_name == NULL || *app_name == '\0')
    {
      char *content_type;

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

      content_type = g_content_type_from_mime_type (info->mime_type);
      if (content_type == NULL)
        return NULL;

      app_info = g_app_info_get_default_for_type (content_type, TRUE);
      g_free (content_type);

      return app_info;
    }

  ai = g_hash_table_lookup (info->apps_lookup, app_name);
  if (ai == NULL)
    {
      g_set_error (error, GTK_RECENT_MANAGER_ERROR,
                   GTK_RECENT_MANAGER_ERROR_NOT_REGISTERED,
                   _("No registered application with name '%s' for item with URI '%s' found"),
                   app_name,
                   info->uri);
      return NULL;
    }

  internal_error = NULL;
  app_info = g_app_info_create_from_commandline (ai->exec, ai->name,
                                                 G_APP_INFO_CREATE_NONE,
                                                 &internal_error);
  if (internal_error != NULL)
    {
      g_propagate_error (error, internal_error);
      return NULL;
    }

  return app_info;
}

/*
 * _gtk_recent_manager_sync:
 *
 * Private function for synchronising the recent manager singleton.
 */
void
_gtk_recent_manager_sync (void)
{
  if (recent_manager_singleton)
    {
      /* force a dump of the contents of the recent manager singleton */
      recent_manager_singleton->priv->is_dirty = TRUE;
      gtk_recent_manager_real_changed (recent_manager_singleton);
    }
}