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path: root/embed/ephy-favicon-cache.c
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/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*- */
/*
 *  Copyright © 2002 Jorn Baayen <jorn@nl.linux.org>
 *  Copyright © 2003-2004 Marco Pesenti Gritti
 *  Copyright © 2004, 2005 Christian Persch
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program 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 General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 *
 */

#include "config.h"

#include "ephy-favicon-cache.h"

#include <string.h>
#include <time.h>
#include <sys/stat.h>

#include "ephy-embed-shell.h"
#include "ephy-embed-persist.h"
#include "ephy-file-helpers.h"
#include "ephy-node-common.h"
#include "ephy-node.h"
#include "ephy-debug.h"

#include <glib.h>
#include <glib/gstdio.h>
#include <gio/gio.h>

#define EPHY_FAVICON_CACHE_XML_ROOT    (const xmlChar *)"ephy_favicons_cache"
#define EPHY_FAVICON_CACHE_XML_VERSION (const xmlChar *)"1.1"

#define EPHY_FAVICON_CACHE_OBSOLETE_DAYS 30
#define SECS_PER_DAY (60*60*24)

/* how often to save the cache, in seconds */
#define CACHE_SAVE_INTERVAL (10 * 60) /* seconds */

/* how often to delete old pixbufs from the cache, in seconds */
#define CACHE_CLEANUP_INTERVAL  (5 * 60) /* seconds */

/* how long to keep pixbufs in cache, in seconds. This should be longer than CACHE_CLEANUP_INTERVAL */
#define PIXBUF_CACHE_KEEP_TIME  10 * 60 /* s */

/* this is very generous, most files are 4k */
#define EPHY_FAVICON_MAX_SIZE   64 * 1024 /* byte */

static void ephy_favicon_cache_class_init (EphyFaviconCacheClass *klass);
static void ephy_favicon_cache_init   (EphyFaviconCache *cache);
static void ephy_favicon_cache_finalize   (GObject *object);
static gboolean kill_download         (const char*, EphyEmbedPersist*, EphyFaviconCache*);

#define EPHY_FAVICON_CACHE_GET_PRIVATE(object)(G_TYPE_INSTANCE_GET_PRIVATE ((object), EPHY_TYPE_FAVICON_CACHE, EphyFaviconCachePrivate))

struct _EphyFaviconCachePrivate
{
    char *directory;
    char *xml_file;
    EphyNodeDb *db;
    EphyNode *icons;
    GHashTable *icons_hash;
    GHashTable *downloads_hash;
    guint autosave_timeout;
    guint cleanup_timeout;
    guint dirty : 1;
    guint64 requests;
    guint64 cached;
};

typedef struct
{
    EphyNode *node;
    time_t timestamp;
    GdkPixbuf *pixbuf;
    guint load_failed : 1;
} PixbufCacheEntry;

typedef gboolean (* FilterFunc) (EphyNode*, time_t);

enum
{
    CHANGED,
    LAST_SIGNAL
};

enum
{
    EPHY_NODE_FAVICON_PROP_URL   = 2,
    EPHY_NODE_FAVICON_PROP_FILENAME  = 3,
    EPHY_NODE_FAVICON_PROP_LAST_USED = 4,
    EPHY_NODE_FAVICON_PROP_STATE     = 5,
    EPHY_NODE_FAVICON_PROP_CHECKOLD  = 6,
    EPHY_NODE_FAVICON_PROP_CHECKED   = 7,
};

enum
{
    NEEDS_TYPE_CHECK = 1 << 0,
    NEEDS_RENAME     = 1 << 1,
    NEEDS_ICO_CHECK  = 1 << 2,
    NEEDS_MASK   = 0x3f
};

static guint signals[LAST_SIGNAL];

G_DEFINE_TYPE (EphyFaviconCache, ephy_favicon_cache, G_TYPE_OBJECT)

static void
ephy_favicon_cache_class_init (EphyFaviconCacheClass *klass)
{
    GObjectClass *object_class = G_OBJECT_CLASS (klass);

    object_class->finalize = ephy_favicon_cache_finalize;

    signals[CHANGED] =
        g_signal_new ("changed",
                  G_OBJECT_CLASS_TYPE (object_class),
                  G_SIGNAL_RUN_LAST,
                  G_STRUCT_OFFSET (EphyFaviconCacheClass, changed),
                  NULL, NULL,
                  g_cclosure_marshal_VOID__STRING,
                  G_TYPE_NONE,
                  1,
                  G_TYPE_STRING);

    g_type_class_add_private (object_class, sizeof (EphyFaviconCachePrivate));
}

EphyFaviconCache *
ephy_favicon_cache_new (void)
{
    return EPHY_FAVICON_CACHE (g_object_new (EPHY_TYPE_FAVICON_CACHE, NULL));
}

static void
pixbuf_cache_entry_free (PixbufCacheEntry *entry)
{
    if (entry->pixbuf != NULL)
    {
        g_object_unref (entry->pixbuf);
    }

    g_slice_free (PixbufCacheEntry, entry);
}

static gboolean
icon_is_obsolete (EphyNode *node, time_t now)
{
    int last_visit;

    last_visit = ephy_node_get_property_int
        (node, EPHY_NODE_FAVICON_PROP_LAST_USED);
    return now - last_visit >= EPHY_FAVICON_CACHE_OBSOLETE_DAYS*SECS_PER_DAY;
}

static void
icons_added_cb (EphyNode *node,
        EphyNode *child,
        EphyFaviconCache *eb)
{
    PixbufCacheEntry *entry = g_slice_new0 (PixbufCacheEntry);

    entry->node = child;

    g_hash_table_insert (eb->priv->icons_hash,
                 (char *) ephy_node_get_property_string (child, EPHY_NODE_FAVICON_PROP_URL),
                 entry);
}

static void
icons_removed_cb (EphyNode *node,
          EphyNode *child,
          guint old_index,
          EphyFaviconCache *eb)
{
    g_hash_table_remove (eb->priv->icons_hash,
                 ephy_node_get_property_string (child, EPHY_NODE_FAVICON_PROP_URL));
}

static void
remove_obsolete_icons (EphyFaviconCache *cache,
               FilterFunc filter)
{
    EphyFaviconCachePrivate *priv = cache->priv;
    GPtrArray *children;
    int i;
    time_t now;

    now = time (NULL);

    children = ephy_node_get_children (priv->icons);
    for (i = (int) children->len - 1; i >= 0; i--)
    {
        EphyNode *kid;

        kid = g_ptr_array_index (children, i);

        if (!filter || filter (kid, now))
        {
            const char *filename;
            char *path;

            filename = ephy_node_get_property_string
                (kid, EPHY_NODE_FAVICON_PROP_FILENAME);
            path = g_build_filename (priv->directory,
                         filename, NULL);
            if (g_unlink (path) < 0)
            {
                LOG ("Unable to delete %s", path);
            }

            g_free (path);
            ephy_node_unref (kid);
            priv->dirty = TRUE;
        }
    }
}

static void
prepare_close_cb (EphyEmbedShell *shell,
          EphyFaviconCache *cache)
{
    EphyFaviconCachePrivate *priv = cache->priv;

    g_hash_table_foreach_remove (priv->downloads_hash,
                     (GHRFunc) kill_download, cache);
}

static void
ephy_favicon_cache_save (EphyFaviconCache *cache)
{
    EphyFaviconCachePrivate *priv = cache->priv;
    int ret;

    if (priv->dirty)
    {
        LOG ("Saving favicon cache\n");

        ret = ephy_node_db_write_to_xml_safe
            (cache->priv->db, (const xmlChar *) priv->xml_file,
             EPHY_FAVICON_CACHE_XML_ROOT,
             EPHY_FAVICON_CACHE_XML_VERSION,
             NULL,
             priv->icons, NULL, NULL,
             NULL);

        /* still dirty if save failed */
        priv->dirty = ret < 0;
    }
}

static gboolean
periodic_save_cb (EphyFaviconCache *cache)
{
    ephy_favicon_cache_save (cache);
    return TRUE;
}

static void
cleanup_entry (char *key,
           PixbufCacheEntry *entry,
           time_t* now)
{
    if (entry->pixbuf != NULL &&
        *now - entry->timestamp > PIXBUF_CACHE_KEEP_TIME)
    {
        LOG ("Evicting pixbuf for \"%s\" from pixbuf cache", key);

        g_object_unref (entry->pixbuf);
        entry->pixbuf = NULL;
        entry->load_failed = FALSE;
        entry->timestamp = 0;
    }
}

static gboolean
periodic_cleanup_cb (EphyFaviconCache *cache)
{
    EphyFaviconCachePrivate *priv = cache->priv;
    time_t now;

    LOG ("Cleanup");

    now = time (NULL);
    g_hash_table_foreach (priv->icons_hash, (GHFunc) cleanup_entry, &now);

    return TRUE;
}

static void
ephy_favicon_cache_init (EphyFaviconCache *cache)
{
    EphyFaviconCachePrivate *priv;
    EphyNodeDb *db;

    priv = cache->priv = EPHY_FAVICON_CACHE_GET_PRIVATE (cache);

    db = ephy_node_db_new (EPHY_NODE_DB_SITEICONS);
    cache->priv->db = db;

    cache->priv->xml_file = g_build_filename (ephy_dot_dir (),
                          "ephy-favicon-cache.xml",
                          NULL);

    cache->priv->directory = g_build_filename (ephy_dot_dir (),
                           "favicon_cache",
                           NULL);

    if (g_file_test (cache->priv->directory, G_FILE_TEST_IS_DIR) == FALSE)
    {
        if (mkdir (cache->priv->directory, 488) != 0)
        {
            g_error ("Couldn't mkdir %s.", cache->priv->directory);
        }
    }

    /* The key is owned by the node */
    priv->icons_hash = g_hash_table_new_full (g_str_hash, g_str_equal, NULL,
                          (GDestroyNotify) pixbuf_cache_entry_free);
    priv->downloads_hash = g_hash_table_new_full (g_str_hash,
                              g_str_equal,
                              g_free, NULL);
    
    /* Icons */
    cache->priv->icons = ephy_node_new_with_id (db, ICONS_NODE_ID);
    ephy_node_signal_connect_object (cache->priv->icons,
                     EPHY_NODE_CHILD_ADDED,
                     (EphyNodeCallback) icons_added_cb,
                     G_OBJECT (cache));
    ephy_node_signal_connect_object (cache->priv->icons,
                     EPHY_NODE_CHILD_REMOVED,
                     (EphyNodeCallback) icons_removed_cb,
                     G_OBJECT (cache));

    ephy_node_db_load_from_file (cache->priv->db, cache->priv->xml_file,
                     EPHY_FAVICON_CACHE_XML_ROOT,
                     EPHY_FAVICON_CACHE_XML_VERSION);

    /* listen to prepare-close on the shell */
    g_signal_connect_object (embed_shell, "prepare-close",
                 G_CALLBACK (prepare_close_cb), cache, 0);

    priv->autosave_timeout = g_timeout_add_seconds (CACHE_SAVE_INTERVAL,
                        (GSourceFunc) periodic_save_cb,
                        cache);
    priv->cleanup_timeout = g_timeout_add_seconds (CACHE_CLEANUP_INTERVAL,
                           (GSourceFunc) periodic_cleanup_cb,
                           cache);
}

static gboolean
kill_download (const char *key,
           EphyEmbedPersist *persist,
           EphyFaviconCache *cache)
{
    EphyNode *icon;

    /* disconnect "completed" and "cancelled" callbacks */
    g_signal_handlers_disconnect_matched
        (persist,G_SIGNAL_MATCH_DATA , 0, 0, NULL, NULL, cache);

    /* now cancel the download */
    ephy_embed_persist_cancel (persist);

    icon = g_hash_table_lookup (cache->priv->icons_hash, key);
    g_return_val_if_fail (EPHY_IS_NODE (icon), TRUE);

    ephy_node_unref (icon);

    return TRUE;
}

static void
delete_file (GFile *dir,
         GFileInfo *file_info)
{
    GFileType type;
    
    type = g_file_info_get_file_type (file_info);
    
    if (type == G_FILE_TYPE_REGULAR)
    {
        char *path;
        
        path = g_build_filename (g_file_get_path (dir), 
                     g_file_info_get_name (file_info),
                     NULL);
        if (g_unlink (path) < 0)
        {
            LOG ("Unable to delete %s", path);
        }
        
        g_free (path);
    }                                 
}

static void
ephy_favicon_cache_finalize (GObject *object)
{
    EphyFaviconCache *cache = EPHY_FAVICON_CACHE (object);
    EphyFaviconCachePrivate *priv = cache->priv;

    LOG ("EphyFaviconCache finalising");

    g_hash_table_foreach_remove (priv->downloads_hash,
                     (GHRFunc) kill_download, cache);

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

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

    remove_obsolete_icons (cache, icon_is_obsolete);

    ephy_favicon_cache_save (cache);

    g_free (priv->xml_file);
    g_free (priv->directory);
    g_hash_table_destroy (priv->icons_hash);
    g_hash_table_destroy (priv->downloads_hash);

    g_object_unref (priv->db);

    LOG ("Requests: cached %" G_GUINT64_FORMAT " / total %" G_GUINT64_FORMAT " = %.3f",
         priv->cached, priv->requests, ((double) priv->cached) / ((double) priv->requests));

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

static void
favicon_download_completed_cb (EphyEmbedPersist *persist,
                   EphyFaviconCache *cache)
{
    const char *url;

    url = ephy_embed_persist_get_source (persist);
    g_return_if_fail (url != NULL);

    LOG ("Favicon cache download completed for %s", url);

    g_hash_table_remove (cache->priv->downloads_hash, url);

    g_signal_emit (G_OBJECT (cache), signals[CHANGED], 0, url);

    g_object_unref (persist);

    cache->priv->dirty = TRUE;
}

static void
favicon_download_cancelled_cb (EphyEmbedPersist *persist,
                   EphyFaviconCache *cache)
{
    const char *url, *dest;

    url = ephy_embed_persist_get_source (persist);
    g_return_if_fail (url != NULL);

    LOG ("Favicon cache download cancelled %s", url);

    g_hash_table_remove (cache->priv->downloads_hash, url);

    /* remove a partially downloaded file */
        dest = ephy_embed_persist_get_dest (persist);
    if (g_unlink (dest) < 0)
    {
        LOG ("Unable to delete %s", dest);
    }

    /* FIXME: re-schedule to try again after n days? */

    g_object_unref (persist);

    cache->priv->dirty = TRUE;
}

static void
ephy_favicon_cache_download (EphyFaviconCache *cache,
                 const char *favicon_url,
                 const char *filename)
{
    EphyEmbedPersist *persist;
    char *dest;

    LOG ("Download favicon: %s", favicon_url);

    g_return_if_fail (EPHY_IS_FAVICON_CACHE (cache));
    g_return_if_fail (favicon_url != NULL);
    g_return_if_fail (filename != NULL);

    dest = g_build_filename (cache->priv->directory, filename, NULL);

    persist = EPHY_EMBED_PERSIST
        (g_object_new (EPHY_TYPE_EMBED_PERSIST, NULL));

    ephy_embed_persist_set_dest (persist, dest);
    ephy_embed_persist_set_flags (persist, EPHY_EMBED_PERSIST_NO_VIEW |
                           EPHY_EMBED_PERSIST_NO_CERTDIALOGS |
                           EPHY_EMBED_PERSIST_DO_CONVERSION |
                           EPHY_EMBED_PERSIST_NO_COOKIES
                               );
    ephy_embed_persist_set_max_size (persist, EPHY_FAVICON_MAX_SIZE);
    ephy_embed_persist_set_source (persist, favicon_url);

    g_free (dest);

    g_signal_connect (G_OBJECT (persist), "completed",
              G_CALLBACK (favicon_download_completed_cb), cache);
    g_signal_connect (G_OBJECT (persist), "cancelled",
              G_CALLBACK (favicon_download_cancelled_cb), cache);

    g_hash_table_insert (cache->priv->downloads_hash,
                 g_strdup (favicon_url), persist);

    ephy_embed_persist_save (persist);
}

/**
 * ephy_favicons_cache_get:
 * @cache:
 * @url: the URL of the icon to retrieve
 * 
 * Note: This will always return %NULL for non-http URLs.
 * 
 * Return value: the site icon at @url as a #GdkPixbuf, or %NULL if
 * if could not be retrieved. Unref when you don't need it anymore.
 */
GdkPixbuf *
ephy_favicon_cache_get (EphyFaviconCache *cache,
            const char *url)
{
    EphyFaviconCachePrivate *priv = cache->priv;
    time_t now;
    PixbufCacheEntry *entry;
    EphyNode *icon;
    char *pix_file;
    GdkPixbuf *pixbuf = NULL;
    guint checklevel = NEEDS_MASK;
    int width, height;
    int favicon_checked;

    if (url == NULL) return NULL;

    if (!g_str_has_prefix (url, "http://") &&
        !g_str_has_prefix (url, "https://")) return NULL;

    priv->requests += 1;

    now = time (NULL);

    entry = g_hash_table_lookup (priv->icons_hash, url);

    if (entry != NULL && entry->pixbuf != NULL)
    {
        LOG ("Pixbuf in cache for \"%s\"", url);

        priv->cached += 1;
        entry->timestamp = now;
        return g_object_ref (entry->pixbuf);
    }
    else if (entry != NULL && entry->load_failed)
    {
        /* No need to try again */
        priv->cached += 1;
        return NULL;
    }

    if (entry == NULL)
    {
        char *filename;

        filename = g_compute_checksum_for_string (G_CHECKSUM_MD5, url, -1);

        icon = ephy_node_new (cache->priv->db);
        ephy_node_set_property_string (icon,
                           EPHY_NODE_FAVICON_PROP_URL,
                           url);
        ephy_node_set_property_string (icon,
                           EPHY_NODE_FAVICON_PROP_FILENAME,
                           filename);
        ephy_node_set_property_int (icon,
                        EPHY_NODE_FAVICON_PROP_CHECKED,
                        (int) NEEDS_MASK & ~NEEDS_RENAME);

        /* This will also add an entry to the icons hash */
        ephy_node_add_child (priv->icons, icon);

        ephy_favicon_cache_download (cache, url, filename);

        g_free (filename);

        entry = g_hash_table_lookup (priv->icons_hash, url);
    }

    g_return_val_if_fail (entry != NULL, NULL);
    g_return_val_if_fail (entry->pixbuf == NULL, NULL);

    icon = entry->node;

    /* update timestamp */
    ephy_node_set_property_int (icon, EPHY_NODE_FAVICON_PROP_LAST_USED,
                    now);

    priv->dirty = TRUE;

    if (g_hash_table_lookup (cache->priv->downloads_hash, url) != NULL)
    {
        /* still downloading, return NULL */
        return NULL;
    }

    pix_file = g_build_filename
        (cache->priv->directory,
         ephy_node_get_property_string (icon, EPHY_NODE_FAVICON_PROP_FILENAME),
         NULL);

    /* FIXME queue re-download? */
    if (g_file_test (pix_file, G_FILE_TEST_EXISTS) == FALSE)
    {
        g_free (pix_file);
        return NULL;
    }

    /* Check for supported icon types */
    favicon_checked = ephy_node_get_property_int
        (icon, EPHY_NODE_FAVICON_PROP_CHECKED);
    if (favicon_checked != -1)
    {
        checklevel = (guint) favicon_checked;
    }

    /* First, update the filename */
    if (checklevel & NEEDS_RENAME)
    {
        char *new_pix_file, *urlhash;
        GValue value = { 0, };

        urlhash = g_compute_checksum_for_string (G_CHECKSUM_MD5, url, -1);
        new_pix_file = g_build_filename (cache->priv->directory, urlhash, NULL);

        g_value_init (&value, G_TYPE_STRING);
        g_value_take_string (&value, urlhash);
        ephy_node_set_property (icon, EPHY_NODE_FAVICON_PROP_FILENAME, &value);
        g_value_unset (&value);

        /* rename the file */
        g_rename (pix_file, new_pix_file);

        g_free (pix_file);
        pix_file = new_pix_file;

        checklevel &= ~NEEDS_RENAME;
        ephy_node_set_property_int (icon,
                        EPHY_NODE_FAVICON_PROP_CHECKED,
                        (int) checklevel);
    }

    /* Now check the type. We renamed the file above, so glib does NOT
     * fall back to extension checking if the slow mime check fails for 
     * whatever reason
     */
    if (checklevel & NEEDS_TYPE_CHECK)
    {
        GFile *file;
        GFileInfo *file_info;
        const char *mime_type;
        gboolean valid = FALSE, is_ao = FALSE;
        
        file = g_file_new_for_path (pix_file);
    
        /* Sniff mime type and check if it's safe to open */
        file_info = g_file_query_info (file,
                           G_FILE_ATTRIBUTE_STANDARD_CONTENT_TYPE,
                           0, NULL, NULL);
        mime_type = g_file_info_get_content_type (file_info);
        if (file_info == NULL)
        {
            return NULL;
        }
        valid = strcmp (mime_type, "image/x-ico") == 0 ||
            strcmp (mime_type, "image/vnd.microsoft.icon") == 0 ||
            strcmp (mime_type, "image/png") == 0 ||
            strcmp (mime_type, "image/gif") == 0;
        is_ao = strcmp (mime_type, "application/octet-stream") == 0;

        g_object_unref (file_info);
        g_object_unref (file);

        /* As a special measure, we try to load an application/octet-stream file
         * as an ICO file, since we cannot detect a ICO file without .ico extension
         * (the mime system has no magic for it).
         */
        if (is_ao)
        {
            GdkPixbufLoader *loader;
            char *buf = NULL;
            gsize count = 0;

            loader = gdk_pixbuf_loader_new_with_type ("ico", NULL);
            if (loader != NULL)
            {
                if (g_file_get_contents (pix_file, &buf, &count, NULL))
                {
                    gdk_pixbuf_loader_write (loader, (const guchar *) buf, count, NULL);
                    g_free (buf);
                }
                
                gdk_pixbuf_loader_close (loader, NULL);

                pixbuf = gdk_pixbuf_loader_get_pixbuf (loader);
                if (pixbuf != NULL)
                {
                    g_object_ref (pixbuf);
                    valid = TRUE;
                }
    
                g_object_unref (loader);
            }
        }

        /* persist the check value */
        if (valid)
        {
            checklevel &= ~NEEDS_TYPE_CHECK;
        }
        else
        {
            /* remove invalid file from cache */
            /* gnome_vfs_unlink (pix_file); */
        }

        ephy_node_set_property_int (icon,
                        EPHY_NODE_FAVICON_PROP_CHECKED,
                        (int) checklevel);

        /* epiphany 1.6 compat */
        ephy_node_set_property_boolean
            (icon, EPHY_NODE_FAVICON_PROP_CHECKOLD, valid);
    }

    /* if it still needs the check, mime type couldn't be checked. Deny! */
    if (checklevel & NEEDS_TYPE_CHECK)
    {
        g_free (pix_file);
        return NULL;
    }

    /* we could already have a pixbuf from the application/octet-stream check */
    if (pixbuf == NULL)
    {
        pixbuf = gdk_pixbuf_new_from_file (pix_file, NULL);
    }

    g_free (pix_file);

    if (pixbuf == NULL)
    {
        entry->load_failed = TRUE;
        return NULL;
    }

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

    /* Reject icons that are too small */
    if (width < 12 || height < 12)
    {
        entry->load_failed = TRUE;
        return NULL;
    }

    /* Scale icons that are too big */
    if (width > 16 || height > 16)
    {
        GdkPixbuf *scaled = gdk_pixbuf_scale_simple (pixbuf, 16, 16,
                                 GDK_INTERP_NEAREST);
        g_object_unref (G_OBJECT (pixbuf));
        pixbuf = scaled;
    }

    /* Put the icon in the cache */
    LOG ("Putting pixbuf for \"%s\" in cache", url);

    entry->pixbuf = g_object_ref (pixbuf);
    entry->timestamp = now;
    entry->load_failed = FALSE;

    return pixbuf;
}

/**
 * ephy_favicons_cache_clear:
 * @cache:
 * 
 * Clears the favicon cache and removes any stored icon files from disk.
 */
void
ephy_favicon_cache_clear (EphyFaviconCache *cache)
{
    GFileEnumerator *file_enum;
    GFile *dir;
    GFileInfo *file_info = NULL;
    EphyFaviconCachePrivate *priv = cache->priv;

    g_return_if_fail (EPHY_IS_FAVICON_CACHE (cache));

    remove_obsolete_icons (cache, NULL);
    ephy_favicon_cache_save (cache);

    /* Now remove any remaining files from the cache directory */
    dir = g_file_new_for_path (priv->directory);
    file_enum = g_file_enumerate_children (dir,
                           G_FILE_ATTRIBUTE_STANDARD_TYPE ","
                           G_FILE_ATTRIBUTE_STANDARD_NAME ","
                           G_FILE_ATTRIBUTE_STANDARD_CONTENT_TYPE,
                           0, NULL, NULL);
    file_info = g_file_enumerator_next_file (file_enum, NULL, NULL);
    while (file_info != NULL)
    {
        delete_file (dir, file_info);
        file_info = g_file_enumerator_next_file (file_enum, NULL, NULL);
        g_object_unref (file_info);
    }
    g_object_unref (dir);
    g_file_enumerator_close (file_enum, NULL, NULL);
}