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path: root/src/lib/ethumb_client/ethumb_client.c
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/**
 * @file
 *
 * This is the client-server thumbnail library, see @ref
 * tutorial_ethumb_client.
 *
 * Copyright (C) 2009 by ProFUSION embedded systems
 *
 * 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 2.1 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/>.
 *
 * @author Rafael Antognolli <antognolli@profusion.mobi>
 * @author Gustavo Sverzut Barbieri <barbieri@profusion.mobi>
 */

/**
 * @page tutorial_ethumb_client Client-Server Thumbnailing Tutorial
 *
 * @section tutorial_ethumb_client_intro Introduction
 *
 * Ethumb provides both in process and client-server generation
 * methods. The advantage of the client-server method is that current
 * process will not do the heavy operations that may block, stopping
 * animations and other user interactions. Instead the client library
 * will configure a local #Ethumb instance and mirrors/controls a
 * remote process using DBus. The simple operations like most setters
 * and getters as well as checking for thumbnail existence
 * (ethumb_client_thumb_exists()) is done locally, while expensive
 * (ethumb_client_generate()) are done on server and then reported
 * back to application when it is finished (both success or failure).
 *
 * @section tutorial_ethumb_client_connect Connecting to Server
 *
 * TODO
 *
 * @section tutorial_ethumb_client_generate Requesting Thumbnail Generation
 *
 * TODO
 *
 * @section tutorial_ethumb_client_setup Setup Extra Thumbnail Parameters
 *
 * TODO
 *
 * @section tutorial_ethumb_client_server_died Handle Server Disconnection
 *
 * TODO
 */

/**
 * @cond LOCAL
 */

#ifdef HAVE_CONFIG_H
# include "config.h"
#endif

#include <stdio.h>
#include <stdlib.h>
#include <limits.h>
#include <string.h>
#include <unistd.h>
#include <errno.h>
#include <sys/types.h>
#include <stdbool.h>

#include <Eina.h>
#include <eina_safety_checks.h>
#include <Eldbus.h>
#include <Ethumb.h>
#include <Ecore.h>

#include "Ethumb_Client.h"

#ifndef PATH_MAX
#define PATH_MAX 4096
#endif

#define MAX_ID   2000000

static int _log_dom = -1;
#define DBG(...)      EINA_LOG_DOM_DBG(_log_dom, __VA_ARGS__)
#define INF(...)      EINA_LOG_DOM_INFO(_log_dom, __VA_ARGS__)
#define WRN(...)      EINA_LOG_DOM_WARN(_log_dom, __VA_ARGS__)
#define ERR(...)      EINA_LOG_DOM_ERR(_log_dom, __VA_ARGS__)
#define CRI(...)      EINA_LOG_DOM_CRIT(_log_dom, __VA_ARGS__)

struct _Ethumb_Client
{
   Ethumb                *ethumb;
   int                    id_count;
   Ethumb                *old_ethumb_conf;
   Eldbus_Connection      *conn;
   struct
   {
      Ethumb_Client_Connect_Cb cb;
      void                    *data;
      Eina_Free_Cb             free_data;
   } connect;
   Eina_List             *pending_add;
   Eina_List             *pending_remove;
   Eina_List             *pending_gen;
   Eina_List             *dbus_pending;
   struct
   {
      Ethumb_Client_Die_Cb cb;
      void                *data;
      Eina_Free_Cb         free_data;
   } die;
   Eldbus_Proxy           *proxy;
   Eldbus_Signal_Handler  *generated_sig_handler;
   EINA_REFCOUNT;
   Eina_Bool              connected : 1;
   Eina_Bool              server_started : 1;
   Eina_Bool              invalid : 1;
};

struct _ethumb_pending_add
{
   int32_t                   id;
   const char               *file;
   const char               *key;
   const char               *thumb;
   const char               *thumb_key;
   Ethumb_Client_Generate_Cb generated_cb;
   void                     *data;
   Eina_Free_Cb              free_data;
   Eldbus_Pending           *pending_call;
   Ethumb_Client            *client;
};

struct _ethumb_pending_remove
{
   int32_t                          id;
   Ethumb_Client_Generate_Cancel_Cb cancel_cb;
   void                            *data;
   Eina_Free_Cb                     free_data;
   Eldbus_Pending                  *pending_call;
   Ethumb_Client                   *client;
};

struct _ethumb_pending_gen
{
   int32_t                   id;
   const char               *file;
   const char               *key;
   const char               *thumb;
   const char               *thumb_key;
   Ethumb_Client_Generate_Cb generated_cb;
   void                     *data;
   Eina_Free_Cb              free_data;
};

typedef struct _Ethumb_Async_Exists Ethumb_Async_Exists;

struct _Ethumb_Async_Exists
{
   const char   *path;

   Ethumb       *dup; /* We will work on that one to prevent race and lock */

   Eina_List    *callbacks;
   Ecore_Thread *thread;
};

struct _Ethumb_Exists
{
   Ethumb_Async_Exists          *parent;
   Ethumb_Client                *client;
   Ethumb                       *dup; /* We don't want to loose parameters so keep them around */

   Ethumb_Client_Thumb_Exists_Cb exists_cb;
   const void                   *data;
};

static const char _ethumb_dbus_bus_name[] = "org.enlightenment.Ethumb";
static const char _ethumb_dbus_interface[] = "org.enlightenment.Ethumb";
static const char _ethumb_dbus_objects_interface[] = "org.enlightenment.Ethumb.objects";
static const char _ethumb_dbus_path[] = "/org/enlightenment/Ethumb";

static int _initcount = 0;
static Eina_Hash *_exists_request = NULL;

static void _ethumb_client_generated_cb(void *data, const Eldbus_Message *msg);
static void _ethumb_client_call_new(Ethumb_Client *client);
static void _ethumb_client_name_owner_changed(void *context, const char *bus, const char *old_id, const char *new_id);

static void
_ethumb_client_free(Ethumb_Client *client)
{
   void *data;
   Eldbus_Object *obj;

   if (client->invalid)
      return;

     {
        Eldbus_Pending *pending;
        EINA_LIST_FREE(client->dbus_pending, pending)
           eldbus_pending_cancel(pending);
     }

   client->invalid = EINA_TRUE;
   EINA_LIST_FREE(client->pending_add, data)
     {
        struct _ethumb_pending_add *pending = data;
        if (pending->pending_call)
          {
             eldbus_pending_cancel(pending->pending_call);
             pending->client = NULL;
          }
        else
          {
             pending->client = NULL;
             free(pending);
          }
     }

   EINA_LIST_FREE(client->pending_gen, data)
     {
        struct _ethumb_pending_gen *pending = data;
        eina_stringshare_del(pending->file);
        eina_stringshare_del(pending->key);
        eina_stringshare_del(pending->thumb);
        eina_stringshare_del(pending->thumb_key);
        if (pending->free_data)
          pending->free_data(pending->data);
        free(pending);
     }

   EINA_LIST_FREE(client->pending_remove, data)
     {
        struct _ethumb_pending_remove *pending = data;
        if (pending->free_data)
          pending->free_data(pending->data);
        if (pending->pending_call)
          {
             eldbus_pending_cancel(pending->pending_call);
             pending->client = NULL;
          }
        else
          {
             pending->client = NULL;
             free(pending);
          }
     }

   if (client->old_ethumb_conf)
     {
        ethumb_free(client->old_ethumb_conf);
        client->old_ethumb_conf = NULL;
     }

   if (client->ethumb)
     {
        ethumb_free(client->ethumb);
        client->ethumb = NULL;
     }

   if (client->conn)
     eldbus_name_owner_changed_callback_del(client->conn,
                                            _ethumb_dbus_bus_name,
                                            _ethumb_client_name_owner_changed,
                                            client);
   if (client->generated_sig_handler)
     {
        eldbus_signal_handler_del(client->generated_sig_handler);
        client->generated_sig_handler = NULL;
     }
   if (client->proxy)
     {
        obj = eldbus_proxy_object_get(client->proxy);
        eldbus_proxy_unref(client->proxy);
        client->proxy = NULL;
        if (obj) eldbus_object_unref(obj);
     }
   if (client->conn)
     {
        eldbus_connection_unref(client->conn);
        client->conn = NULL;
     }

   if (client->connect.free_data)
     client->connect.free_data(client->connect.data);
   if (client->die.free_data)
     client->die.free_data(client->die.data);

   free(client);
}

static void
_ethumb_async_delete(void *data)
{
   Ethumb_Async_Exists *async = data;

   EINA_SAFETY_ON_FALSE_RETURN(async->callbacks == NULL);
   EINA_SAFETY_ON_FALSE_RETURN(async->thread == NULL);

   ethumb_free(async->dup);
   eina_stringshare_del(async->path);

   free(async);
}

static void
_ethumb_client_name_owner_changed(void *context, const char *bus EINA_UNUSED, const char *old_id, const char *new_id)
{
   Ethumb_Client *client = context;

   DBG("NameOwnerChanged from=[%s] to=[%s]", old_id, new_id);
   if (new_id[0])
     {
        if (client->connected)
          return;

        client->connected = EINA_TRUE;
        INF("Server connected");
        _ethumb_client_call_new(client);
        return;
     }
   INF("Server disconnected");
   EINA_REFCOUNT_REF(client);
   client->connected = EINA_FALSE;
   if (client->die.cb)
     {
        client->die.cb(client->die.data, client);
        client->die.cb = NULL;
     }
   if (client->die.free_data)
     {
        client->die.free_data(client->die.data);
        client->die.free_data = NULL;
        client->die.data = NULL;
     }
   EINA_REFCOUNT_UNREF(client) _ethumb_client_free(client);
}

static void
_ethumb_client_report_connect(Ethumb_Client *client, Eina_Bool success)
{
   if (!client->connect.cb)
     {
        //ERR("already called?!");
        return;
     }

   EINA_REFCOUNT_REF(client);
   if (success)
     INF("Success connecting to Ethumb server.");
   else
     ERR("Could not connect to Ethumb server.");

   client->connect.cb(client->connect.data, client, success);
   if (client->connect.free_data)
     {
        client->connect.free_data(client->connect.data);
        client->connect.free_data = NULL;
     }
   client->connect.cb = NULL;
   client->connect.data = NULL;
   EINA_REFCOUNT_UNREF(client) _ethumb_client_free(client);
}

static void
_ethumb_client_new_cb(void *data, const Eldbus_Message *msg, Eldbus_Pending *pending)
{
   const char *errname, *errmsg;
   const char *opath;
   Ethumb_Client *client = data;
   Eldbus_Object *obj;

   client->dbus_pending = eina_list_remove(client->dbus_pending, pending);
   if (eldbus_message_error_get(msg, &errname, &errmsg))
     {
        ERR("Error: %s %s", errname, errmsg);
        _ethumb_client_report_connect(client, 0);
        return;
     }

   if (!eldbus_message_arguments_get(msg, "o", &opath))
     {
        ERR("Error: could not get entry contents");
        _ethumb_client_report_connect(client, 0);
        return;
     }

   if (client->generated_sig_handler)
     {
        eldbus_signal_handler_del(client->generated_sig_handler);
        client->generated_sig_handler = NULL;
     }
   if (!client->proxy)
     {
        obj = eldbus_object_get(client->conn, _ethumb_dbus_bus_name, opath);
        client->proxy = eldbus_proxy_get(obj, _ethumb_dbus_objects_interface);
     }
   client->generated_sig_handler =
     eldbus_proxy_signal_handler_add(client->proxy, "generated",
                                     _ethumb_client_generated_cb, client);
   _ethumb_client_report_connect(client, 1);
}

static void
_ethumb_client_call_new(Ethumb_Client *client)
{
   Eldbus_Message *msg;
   Eldbus_Pending *pending;
   msg = eldbus_message_method_call_new(_ethumb_dbus_bus_name,
                                       _ethumb_dbus_path,
                                       _ethumb_dbus_interface, "new");
   pending = eldbus_connection_send(client->conn, msg,
                                    _ethumb_client_new_cb, client, -1);
   if (pending)
     client->dbus_pending = eina_list_append(client->dbus_pending, pending);
}

static void
_ethumb_client_exists_heavy(void *data, Ecore_Thread *thread EINA_UNUSED)
{
   Ethumb_Async_Exists *async = data;

   ethumb_thumb_hash(async->dup);
}

static void
_ethumb_client_exists_end(void *data, Ecore_Thread *thread EINA_UNUSED)
{
   Ethumb_Async_Exists *async = data;
   Ethumb_Exists *cb;

   EINA_LIST_FREE(async->callbacks, cb)
     {
        Ethumb *tmp;

        ethumb_thumb_hash_copy(cb->dup, async->dup);
        tmp = cb->client->ethumb;
        cb->client->ethumb = cb->dup;

        cb->exists_cb((void *)cb->data,
                      cb->client, cb,
                      ethumb_exists(cb->client->ethumb));

        cb->client->ethumb = tmp;
        EINA_REFCOUNT_UNREF(cb->client) _ethumb_client_free(cb->client);
        ethumb_free(cb->dup);
        free(cb);
     }

   async->thread = NULL;

   eina_hash_del(_exists_request, async->path, async);
}

/**
 * @endcond
 */

/**
 * @brief Initialize the Ethumb_Client library.
 *
 * @return 1 or greater on success, 0 on error.
 *
 * This function sets up all the Ethumb_Client module dependencies. It
 * returns 0 on failure (that is, when one of the dependency fails to
 * initialize), otherwise it returns the number of times it has
 * already been called.
 *
 * When Ethumb_Client is not used anymore, call
 * ethumb_client_shutdown() to shut down the Ethumb_Client library.
 *
 * @see ethumb_client_shutdown()
 * @see ethumb_client_connect()
 * @see @ref tutorial_ethumb_client
 */
EAPI int
ethumb_client_init(void)
{
   if (_initcount)
     return ++_initcount;

   if (!eina_init())
     {
        fprintf(stderr, "ERROR: Could not initialize log module.\n");
        return 0;
     }
   _log_dom = eina_log_domain_register("ethumb_client", EINA_COLOR_YELLOW);
   if (_log_dom < 0)
     {
        EINA_LOG_ERR("Could not register log domain: ethumb_client");
        eina_shutdown();
        return 0;
     }

   ethumb_init();
   eldbus_init();

   _exists_request = eina_hash_stringshared_new(_ethumb_async_delete);

   return ++_initcount;
}

/**
 * @brief Shut down the Ethumb_Client library.
 *
 * @return 0 when everything is shut down, 1 or greater if there are
 *         other users of the Ethumb_Client library pending shutdown.
 *
 * This function shuts down the Ethumb_Client library. It returns 0
 * when it has been called the same number of times than
 * ethumb_client_init(). In that case it shut down all the
 * Ethumb_Client modules dependencies.
 *
 * Once this function succeeds (that is, @c 0 is returned), you must
 * not call any of the Eina function anymore. You must call
 * ethumb_client_init() again to use the Ethumb_Client functions
 * again.
 */
EAPI int
ethumb_client_shutdown(void)
{
   _initcount--;
   if (_initcount > 0)
     return _initcount;

   /* should find a non racy solution to closing all pending exists request */
   eina_hash_free(_exists_request);
   _exists_request = NULL;

   eldbus_shutdown();
   ethumb_shutdown();
   eina_log_domain_unregister(_log_dom);
   _log_dom = -1;
   eina_shutdown();
   return _initcount;
}

static void
_name_start(void *data EINA_UNUSED, const Eldbus_Message *msg, Eldbus_Pending *pending EINA_UNUSED)
{
   const char *name, *text;
   if (eldbus_message_error_get(msg, &name, &text))
     {
        ERR("Starting ethumb failed %s %s", name, text);
        return;
     }
}

/**
 * Connects to Ethumb server and return the client instance.
 *
 * This is the "constructor" of Ethumb_Client, where everything
 * starts.
 *
 * If server was down, it is tried to start it using DBus activation,
 * then the connection is retried.
 *
 * This call is asynchronous and will not block, instead it will be in
 * "not connected" state until @a connect_cb is called with either
 * success or failure. On failure, then no methods should be
 * called. On success you're now able to setup and then ask generation
 * of thumbnails.
 *
 * Usually you should listen for server death/disconenction with
 * ethumb_client_on_server_die_callback_set().
 *
 * @param connect_cb function to call to report connection success or
 *        failure. Do not call any other ethumb_client method until
 *        this function returns. The first received parameter is the
 *        given argument @a data. Must @b not be @c NULL. This
 *        function will not be called if user explicitly calls
 *        ethumb_client_disconnect().
 * @param data context to give back to @a connect_cb. May be @c NULL.
 * @param free_data function used to release @a data resources, if
 *        any. May be @c NULL. If this function exists, it will be
 *        called immediately after @a connect_cb is called or if user
 *        explicitly calls ethumb_client_disconnect() before such
 *        (that is, don't rely on @a data after @a connect_cb was
 *        called!)
 *
 * @return client instance or NULL if failed. If @a connect_cb is
 *         missing it returns @c NULL. If it fail for other
 *         conditions, @c NULL is also returned and @a connect_cb is
 *         called with @c success=EINA_FALSE. The client instance is
 *         not ready to be used until @a connect_cb is called.
 */
EAPI Ethumb_Client *
ethumb_client_connect(Ethumb_Client_Connect_Cb connect_cb, const void *data, Eina_Free_Cb free_data)
{
   Ethumb_Client *eclient;

   EINA_SAFETY_ON_NULL_RETURN_VAL(connect_cb, NULL);

   eclient = calloc(1, sizeof(*eclient));
   if (!eclient)
     {
        ERR("could not allocate Ethumb_Client structure.");
        goto err;
     }

   eclient->old_ethumb_conf = NULL;
   eclient->connect.cb = connect_cb;
   eclient->connect.data = (void *)data;
   eclient->connect.free_data = free_data;

   eclient->ethumb = ethumb_new();
   if (!eclient->ethumb)
     {
        ERR("could not create ethumb handler.");
        goto ethumb_new_err;
     }

   eclient->conn = eldbus_connection_get(ELDBUS_CONNECTION_TYPE_SESSION);
   if (!eclient->conn)
     {
        ERR("could not connect to session bus.");
        goto connection_err;
     }

   if (!eldbus_name_start(eclient->conn, _ethumb_dbus_bus_name, 0, _name_start, NULL))
     {
        ERR("Failed to start ethumb bus");
        goto connection_err;
     }

   eldbus_name_owner_changed_callback_add(eclient->conn, _ethumb_dbus_bus_name,
                                         _ethumb_client_name_owner_changed,
                                         eclient, EINA_TRUE);
   EINA_REFCOUNT_INIT(eclient);

   return eclient;

connection_err:
   ethumb_free(eclient->ethumb);
ethumb_new_err:
   free(eclient);
err:
   connect_cb((void *)data, NULL, EINA_FALSE);
   if (free_data)
     free_data((void *)data);
   return NULL;
}

/**
 * Disconnect the client, releasing all client resources.
 *
 * This is the destructor of Ethumb_Client, after it's disconnected
 * the client handle is now gone and should not be used.
 *
 * @param client client instance to be destroyed. Must @b not be @c
 *        NULL.
 */
EAPI void
ethumb_client_disconnect(Ethumb_Client *client)
{
   EINA_SAFETY_ON_NULL_RETURN(client);

   EINA_REFCOUNT_UNREF(client) _ethumb_client_free(client);
}

/**
 * Sets the callback to report server died.
 *
 * When server dies there is nothing you can do, just release
 * resources with ethumb_client_disconnect() and probably try to
 * connect again.
 *
 * Usually you should set this callback and handle this case, it does
 * happen!
 *
 * @param client the client instance to monitor. Must @b not be @c
 *        NULL.
 * @param server_die_cb function to call back when server dies. The
 *        first parameter will be the argument @a data. May be @c
 *        NULL.
 * @param data context to give back to @a server_die_cb. May be @c
 *        NULL.
 * @param free_data used to release @a data resources after @a
 *        server_die_cb is called or user calls
 *        ethumb_client_disconnect().
 */
EAPI void
ethumb_client_on_server_die_callback_set(Ethumb_Client *client, Ethumb_Client_Die_Cb server_die_cb, const void *data, Eina_Free_Cb free_data)
{
   EINA_SAFETY_ON_NULL_RETURN(client);

   if (client->die.free_data)
     client->die.free_data(client->die.data);

   client->die.cb = server_die_cb;
   client->die.data = (void *)data;
   client->die.free_data = free_data;
}

/**
 * @cond LOCAL
 */

static void
_ethumb_client_ethumb_setup_cb(void *data, const Eldbus_Message *msg, Eldbus_Pending *pending)
{
   const char *errname, *errmsg;
   Eina_Bool result = 0;
   Ethumb_Client *client = data;

   client->dbus_pending = eina_list_remove(client->dbus_pending, pending);

   if (eldbus_message_error_get(msg, &errname, &errmsg))
     {
        ERR("Error: %s %s", errname, errmsg);
        return;
     }

   if (!eldbus_message_arguments_get(msg, "b", &result))
     {
        ERR("Error getting arguments");
        return;
     }
   EINA_SAFETY_ON_FALSE_RETURN(result);
}

static const char *
_ethumb_client_dbus_get_bytearray(Eldbus_Message_Iter *array)
{
   int length;
   const char *result;

   if (eldbus_message_iter_fixed_array_get(array, 'y', &result, &length))
     return eina_stringshare_add_length(result, length);
   else
     {
        ERR("Not byte array. Signature: %s",
            eldbus_message_iter_signature_get(array));
        return NULL;
     }
}

static void
_ethumb_client_dbus_append_bytearray(Eldbus_Message_Iter *parent, const char *string)
{
   int i, size;
   Eldbus_Message_Iter *array;

   if (!string)
     string = "";

   array = eldbus_message_iter_container_new(parent, 'a', "y");
   size = strlen(string) + 1;
   for (i = 0; i < size; i++)
     eldbus_message_iter_basic_append(array, 'y', string[i]);
   eldbus_message_iter_container_close(parent, array);
}

/**
 * @endcond
 */

static Eldbus_Message_Iter *
_setup_iterator_open(Eldbus_Message_Iter *array, Eldbus_Message_Iter **entry, const char *key, const char *type)
{
   Eldbus_Message_Iter *variant, *_struct;
   eldbus_message_iter_arguments_append(array, "{sv}", &_struct);
   eldbus_message_iter_basic_append(_struct, 's', key);
   variant = eldbus_message_iter_container_new(_struct, 'v', type);

   *entry = _struct;
   return variant;
}

static void
_setup_iterator_close(Eldbus_Message_Iter *array, Eldbus_Message_Iter *entry, Eldbus_Message_Iter *variant)
{
   eldbus_message_iter_container_close(entry, variant);
   eldbus_message_iter_container_close(array, entry);
}

/**
 * Send setup to server.
 *
 * This method is called automatically by ethumb_client_generate() if
 * any property was changed. No need to call it manually.
 *
 * @param client client instance. Must @b not be @c NULL and client
 *        must be connected (after connected_cb is called).
 */
EAPI void
ethumb_client_ethumb_setup(Ethumb_Client *client)
{
   Eldbus_Message *msg;
   Eldbus_Message_Iter *array, *main_iter;
   Eldbus_Message_Iter *entry, *variant;
   Eldbus_Message_Iter *sub_struct;
   Ethumb *e = client->ethumb;
   int tw, th, format, aspect, orientation, quality, compress;
   float cx, cy;
   const char *theme_file, *group, *swallow;
   const char *directory, *category;
   double video_time, video_start, video_interval;
   unsigned int video_ntimes, video_fps, document_page;
   Eldbus_Pending *pending;

   EINA_SAFETY_ON_NULL_RETURN(client);
   EINA_SAFETY_ON_FALSE_RETURN(client->connected);

   msg = eldbus_proxy_method_call_new(client->proxy, "ethumb_setup");
   main_iter = eldbus_message_iter_get(msg);
   eldbus_message_iter_arguments_append(main_iter, "a{sv}", &array);

   /* starting array elements */
   variant = _setup_iterator_open(array, &entry, "size", "(ii)");
   eldbus_message_iter_arguments_append(variant, "(ii)", &sub_struct);
   ethumb_thumb_size_get(e, &tw, &th);
   eldbus_message_iter_arguments_append(sub_struct, "ii", tw, th);
   eldbus_message_iter_container_close(variant, sub_struct);
   _setup_iterator_close(array, entry, variant);

   variant = _setup_iterator_open(array, &entry, "format", "i");
   format = ethumb_thumb_format_get(e);
   eldbus_message_iter_arguments_append(variant, "i", format);
   _setup_iterator_close(array, entry, variant);

   variant = _setup_iterator_open(array, &entry, "aspect", "i");
   aspect = ethumb_thumb_aspect_get(e);
   eldbus_message_iter_arguments_append(variant, "i", aspect);
   _setup_iterator_close(array, entry, variant);

   variant = _setup_iterator_open(array, &entry, "orientation", "i");
   orientation = ethumb_thumb_orientation_get(e);
   eldbus_message_iter_arguments_append(variant, "i", orientation);
   _setup_iterator_close(array, entry, variant);

   variant = _setup_iterator_open(array, &entry, "crop", "(dd)");
   eldbus_message_iter_arguments_append(variant, "(dd)", &sub_struct);
   ethumb_thumb_crop_align_get(e, &cx, &cy);
   eldbus_message_iter_arguments_append(sub_struct, "dd", (double)cx, (double)cy);
   eldbus_message_iter_container_close(variant, sub_struct);
   _setup_iterator_close(array, entry, variant);

   variant = _setup_iterator_open(array, &entry, "quality", "i");
   quality = ethumb_thumb_quality_get(e);
   eldbus_message_iter_arguments_append(variant, "i", quality);
   _setup_iterator_close(array, entry, variant);

   variant = _setup_iterator_open(array, &entry, "compress", "i");
   compress = ethumb_thumb_compress_get(e);
   eldbus_message_iter_arguments_append(variant, "i", compress);
   _setup_iterator_close(array, entry, variant);

   variant = _setup_iterator_open(array, &entry, "frame", "(ayayay)");
   eldbus_message_iter_arguments_append(variant, "(ayayay)", &sub_struct);
   ethumb_frame_get(e, &theme_file, &group, &swallow);
   _ethumb_client_dbus_append_bytearray(sub_struct, theme_file);
   _ethumb_client_dbus_append_bytearray(sub_struct, group);
   _ethumb_client_dbus_append_bytearray(sub_struct, swallow);
   eldbus_message_iter_container_close(variant, sub_struct);
   _setup_iterator_close(array, entry, variant);

   variant = _setup_iterator_open(array, &entry, "directory", "ay");
   directory = ethumb_thumb_dir_path_get(e);
   _ethumb_client_dbus_append_bytearray(variant, directory);
   _setup_iterator_close(array, entry, variant);

   variant = _setup_iterator_open(array, &entry, "category", "ay");
   category = ethumb_thumb_category_get(e);
   _ethumb_client_dbus_append_bytearray(variant, category);
   _setup_iterator_close(array, entry, variant);

   variant = _setup_iterator_open(array, &entry, "video_time", "d");
   video_time = ethumb_video_time_get(e);
   eldbus_message_iter_arguments_append(variant, "d", video_time);
   _setup_iterator_close(array, entry, variant);

   variant = _setup_iterator_open(array, &entry, "video_start", "d");
   video_start = ethumb_video_start_get(e);
   eldbus_message_iter_arguments_append(variant, "d", video_start);
   _setup_iterator_close(array, entry, variant);

   variant = _setup_iterator_open(array, &entry, "video_interval", "d");
   video_interval = ethumb_video_interval_get(e);
   eldbus_message_iter_arguments_append(variant, "d", video_interval);
   _setup_iterator_close(array, entry, variant);

   variant = _setup_iterator_open(array, &entry, "video_ntimes", "u");
   video_ntimes = ethumb_video_ntimes_get(e);
   eldbus_message_iter_arguments_append(variant, "u", video_ntimes);
   _setup_iterator_close(array, entry, variant);

   variant = _setup_iterator_open(array, &entry, "video_fps", "u");
   video_fps = ethumb_video_fps_get(e);
   eldbus_message_iter_arguments_append(variant, "u", video_fps);
   _setup_iterator_close(array, entry, variant);

   variant = _setup_iterator_open(array, &entry, "document_page", "u");
   document_page = ethumb_document_page_get(e);
   eldbus_message_iter_arguments_append(variant, "u", document_page);
   _setup_iterator_close(array, entry, variant);

   eldbus_message_iter_container_close(main_iter, array);

   pending = eldbus_proxy_send(client->proxy, msg,
                               _ethumb_client_ethumb_setup_cb, client, -1);
   if (pending)
     client->dbus_pending = eina_list_append(client->dbus_pending, pending);
}

/**
 * @cond LOCAL
 */
static void
_ethumb_client_generated_cb(void *data, const Eldbus_Message *msg)
{
   int id = -1;
   Ethumb_Client *client = data;
   Eldbus_Message_Iter *thumb_iter;
   Eldbus_Message_Iter *thumb_key_iter;
   Eina_Bool success;
   int found;
   struct _ethumb_pending_gen *pending;
   Eina_List *l;

   if (!client) return;
   if (!eldbus_message_arguments_get(msg, "iayayb", &id, &thumb_iter,
                                    &thumb_key_iter, &success))
     {
        ERR("Error getting data from signal.");
        return;
     }

   found = 0;
   l = client->pending_gen;
   while (l)
     {
        pending = l->data;
        if (pending->id == id)
          {
             found = 1;
             break;
          }
        l = l->next;
     }

   if (found)
     {
        const char *thumb = _ethumb_client_dbus_get_bytearray(thumb_iter);
        const char *thumb_key = _ethumb_client_dbus_get_bytearray(thumb_key_iter);

        client->pending_gen = eina_list_remove_list(client->pending_gen, l);
        if (pending->generated_cb)
          pending->generated_cb(pending->data, client, id,
                                pending->file, pending->key,
                                thumb, thumb_key,
                                success);
        if (pending->free_data)
          pending->free_data(pending->data);
        eina_stringshare_del(pending->file);
        eina_stringshare_del(pending->key);
        eina_stringshare_del(pending->thumb);
        eina_stringshare_del(pending->thumb_key);
        eina_stringshare_del(thumb);
        eina_stringshare_del(thumb_key);
        free(pending);
     }
}

static void
_ethumb_client_queue_add_cb(void *data, const Eldbus_Message *msg, Eldbus_Pending *eldbus_pending EINA_UNUSED)
{
   const char *errname, *errmsg;
   int32_t id;
   struct _ethumb_pending_add *pending = data;
   struct _ethumb_pending_gen *generating;
   Ethumb_Client *client = pending->client;

   pending->pending_call = NULL;
   if (!client) goto end;
   client->pending_add = eina_list_remove(client->pending_add, pending);
   
   if (eldbus_message_error_get(msg, &errname, &errmsg))
     {
        ERR("Error: %s %s", errname, errmsg);
        goto end;
     }

   if (!eldbus_message_arguments_get(msg, "i", &id))
     {
        ERR("Error getting arguments.");
        goto end;
     }

   
   generating = calloc(1, sizeof(*generating));
   generating->id = id;
   generating->file = pending->file;
   generating->key = pending->key;
   generating->thumb = pending->thumb;
   generating->thumb_key = pending->thumb_key;
   generating->generated_cb = pending->generated_cb;
   generating->data = pending->data;
   generating->free_data = pending->free_data;
   client->pending_gen = eina_list_append(client->pending_gen, generating);

   free(pending);
   return;

end:
   eina_stringshare_del(pending->file);
   eina_stringshare_del(pending->key);
   eina_stringshare_del(pending->thumb);
   eina_stringshare_del(pending->thumb_key);
   if (pending->free_data)
     pending->free_data(pending->data);
   free(pending);
}

static int
_ethumb_client_queue_add(Ethumb_Client *client, const char *file, const char *key, const char *thumb, const char *thumb_key, Ethumb_Client_Generate_Cb generated_cb, const void *data, Eina_Free_Cb free_data)
{
   Eldbus_Message *msg;
   Eldbus_Message_Iter *main_itr;
   struct _ethumb_pending_add *pending;

   pending = calloc(1, sizeof(*pending));
   pending->id = client->id_count;
   pending->file = eina_stringshare_add(file);
   pending->key = eina_stringshare_add(key);
   pending->thumb = eina_stringshare_add(thumb);
   pending->thumb_key = eina_stringshare_add(thumb_key);
   pending->generated_cb = generated_cb;
   pending->data = (void *)data;
   pending->free_data = free_data;
   pending->client = client;

   client->id_count = (client->id_count + 1) % MAX_ID;

   msg = eldbus_proxy_method_call_new(client->proxy, "queue_add");
   main_itr = eldbus_message_iter_get(msg);
   eldbus_message_iter_basic_append(main_itr, 'i', pending->id);
   _ethumb_client_dbus_append_bytearray(main_itr, file);
   _ethumb_client_dbus_append_bytearray(main_itr, key);
   _ethumb_client_dbus_append_bytearray(main_itr, thumb);
   _ethumb_client_dbus_append_bytearray(main_itr, thumb_key);

   client->pending_add = eina_list_append(client->pending_add, pending);
   
   pending->pending_call = eldbus_proxy_send(client->proxy, msg,
                                             _ethumb_client_queue_add_cb,
                                             pending, -1);

   return pending->id;
}

static void
_ethumb_client_queue_remove_cb(void *data, const Eldbus_Message *msg, Eldbus_Pending *eldbus_pending EINA_UNUSED)
{
   Eina_Bool success = EINA_FALSE;
   struct _ethumb_pending_remove *pending = data;
   Ethumb_Client *client = pending->client;
   const char *errname, *errmsg;

   pending->pending_call = NULL;
   if (!client) goto end;
   client->pending_remove = eina_list_remove(client->pending_remove, pending);

   if (eldbus_message_error_get(msg, &errname, &errmsg))
     {
        ERR("Error: %s %s", errname, errmsg);
        goto end;
     }

   if (!eldbus_message_arguments_get(msg, "b", &success))
     {
        ERR("Error getting arguments.");
        goto end;
     }

end:
   if (pending->cancel_cb)
     pending->cancel_cb(pending->data, success);
   if (pending->free_data)
     pending->free_data(pending->data);
   free(pending);
}

/**
 * @endcond
 */

/**
 * Ask server to cancel generation of thumbnail.
 *
 * @param client client instance. Must @b not be @c NULL and client
 *        must be connected (after connected_cb is called).
 * @param id valid id returned by ethumb_client_generate()
 * @param cancel_cb function to report cancellation results.
 * @param data context argument to give back to @a cancel_cb. May be
 *        @c NULL.
 * @param data context to give back to @a cancel_cb. May be @c
 *        NULL.
 * @param free_data used to release @a data resources after @a
 *        cancel_cb is called or user calls
 *        ethumb_client_disconnect().
 */
EAPI void
ethumb_client_generate_cancel(Ethumb_Client *client, int id, Ethumb_Client_Generate_Cancel_Cb cancel_cb, const void *data, Eina_Free_Cb free_data)
{
   struct _ethumb_pending_remove *pending;
   Eina_List *l;
   int found;
   int32_t id32 = id;
   EINA_SAFETY_ON_NULL_RETURN(client);
   EINA_SAFETY_ON_FALSE_RETURN(id >= 0);

   pending = calloc(1, sizeof(*pending));
   pending->id = id;
   pending->cancel_cb = cancel_cb;
   pending->data = (void *)data;
   pending->free_data = free_data;
   pending->client = client;

   pending->pending_call =
     eldbus_proxy_call(client->proxy, "queue_remove",
                       _ethumb_client_queue_remove_cb, pending, -1,
                       "i", pending->id);
   client->pending_remove = eina_list_append(client->pending_remove, pending);

   /*
    * Check if answer was not received yet cancel it
    * callback of queue_add will be called with a error msg
    * and data will be freed
    */
   found = 0;
   l = client->pending_add;
   while (l)
     {
        struct _ethumb_pending_add *pending_add = l->data;
        if (pending_add->id != id32)
          {
             l = l->next;
             continue;
          }
        if (pending_add->pending_call)
          {
             Eldbus_Pending *call = pending_add->pending_call;

             pending_add->pending_call = NULL;
             eldbus_pending_cancel(call);
          }
        found = 1;
        break;
     }

   if (found)
     return;

   //if already received answer only free memory
   l = client->pending_gen;
   while (l)
     {
        struct _ethumb_pending_gen *pending_gen = l->data;
        if (pending_gen->id != id32)
          {
             l = l->next;
             continue;
          }
        client->pending_gen = eina_list_remove_list(client->pending_gen, l);
        eina_stringshare_del(pending_gen->file);
        eina_stringshare_del(pending_gen->key);
        eina_stringshare_del(pending_gen->thumb);
        eina_stringshare_del(pending_gen->thumb_key);
        if (pending_gen->free_data)
          pending_gen->free_data(pending_gen->data);
        free(pending_gen);
        break;
     }
}

/**
 * Ask server to cancel generation of all thumbnails.
 *
 * @param client client instance. Must @b not be @c NULL and client
 *        must be connected (after connected_cb is called).
 *
 * @see ethumb_client_generate_cancel()
 */
EAPI void
ethumb_client_generate_cancel_all(Ethumb_Client *client)
{
   void *data;
   EINA_SAFETY_ON_NULL_RETURN(client);

   EINA_LIST_FREE(client->pending_add, data)
     {
        struct _ethumb_pending_add *pending = data;
        if (pending->pending_call)
          eldbus_pending_cancel(pending->pending_call);
        pending->pending_call = NULL;
        pending->client = NULL;
        free(pending);
     }

   EINA_LIST_FREE(client->pending_gen, data)
     {
        struct _ethumb_pending_gen *pending = data;
        eina_stringshare_del(pending->file);
        eina_stringshare_del(pending->key);
        eina_stringshare_del(pending->thumb);
        eina_stringshare_del(pending->thumb_key);
        if (pending->free_data)
          pending->free_data(pending->data);
        free(pending);
     }

   eldbus_proxy_call(client->proxy, "queue_clear", NULL, NULL, -1, "");
}

/**
 * Configure future requests to use FreeDesktop.Org preset.
 *
 * This is a preset to provide freedesktop.org (fdo) standard
 * compliant thumbnails. That is, files are stored as JPEG under
 * ~/.thumbnails/SIZE, with size being either normal (128x128) or
 * large (256x256).
 *
 * @param client the client instance to use. Must @b not be @c
 *        NULL. May be pending connected (can be called before @c
 *        connected_cb)
 * @param s size identifier, either #ETHUMB_THUMB_NORMAL (0) or
 *        #ETHUMB_THUMB_LARGE (1).
 *
 * @see ethumb_client_size_set()
 * @see ethumb_client_aspect_set()
 * @see ethumb_client_crop_align_set()
 * @see ethumb_client_category_set()
 * @see ethumb_client_dir_path_set()
 */
EAPI void
ethumb_client_fdo_set(Ethumb_Client *client, Ethumb_Thumb_FDO_Size s)
{
   EINA_SAFETY_ON_NULL_RETURN(client);

   if (!client->old_ethumb_conf)
     client->old_ethumb_conf = ethumb_dup(client->ethumb);
   ethumb_thumb_fdo_set(client->ethumb, s);
}

/**
 * Configure future request to use custom size.
 *
 * @param client the client instance to use. Must @b not be @c
 *        NULL. May be pending connected (can be called before @c
 *        connected_cb)
 * @param tw width, default is 128.
 * @param th height, default is 128.
 */
EAPI void
ethumb_client_size_set(Ethumb_Client *client, int tw, int th)
{
   EINA_SAFETY_ON_NULL_RETURN(client);

   if (!client->old_ethumb_conf)
     client->old_ethumb_conf = ethumb_dup(client->ethumb);
   ethumb_thumb_size_set(client->ethumb, tw, th);
}

/**
 * Retrieve future request to use custom size.
 *
 * @param client the client instance to use. Must @b not be @c
 *        NULL. May be pending connected (can be called before @c
 *        connected_cb)
 * @param tw where to return width. May be @c NULL.
 * @param th where to return height. May be @c NULL.
 */
EAPI void
ethumb_client_size_get(const Ethumb_Client *client, int *tw, int *th)
{
   if (tw) *tw = 0;
   if (th) *th = 0;
   EINA_SAFETY_ON_NULL_RETURN(client);

   ethumb_thumb_size_get(client->ethumb, tw, th);
}

/**
 * Configure format to use for future requests.
 *
 * @param client the client instance to use. Must @b not be @c
 *        NULL. May be pending connected (can be called before @c
 *        connected_cb)
 * @param f format identifier to use, either #ETHUMB_THUMB_FDO (0),
 *        #ETHUMB_THUMB_JPEG (1) or #ETHUMB_THUMB_EET (2). Default is FDO.
 */
EAPI void
ethumb_client_format_set(Ethumb_Client *client, Ethumb_Thumb_Format f)
{
   EINA_SAFETY_ON_NULL_RETURN(client);

   if (!client->old_ethumb_conf)
     client->old_ethumb_conf = ethumb_dup(client->ethumb);
   ethumb_thumb_format_set(client->ethumb, f);
}

/**
 * Retrieve format to use for future requests.
 *
 * @param client the client instance to use. Must @b not be @c
 *        NULL. May be pending connected (can be called before @c
 *        connected_cb)
 *
 * @return format identifier to use, either #ETHUMB_THUMB_FDO (0),
 *         #ETHUMB_THUMB_JPEG (1) or #ETHUMB_THUMB_EET (2).
 */
EAPI Ethumb_Thumb_Format
ethumb_client_format_get(const Ethumb_Client *client)
{
   EINA_SAFETY_ON_NULL_RETURN_VAL(client, 0);

   return ethumb_thumb_format_get(client->ethumb);
}

/**
 * Configure aspect mode to use.
 *
 * If aspect is kept (#ETHUMB_THUMB_KEEP_ASPECT), then image will be
 * rescaled so the largest dimension is not bigger than it's specified
 * size (see ethumb_client_size_get()) and the other dimension is
 * resized in the same proportion. Example: size is 256x256, image is
 * 1000x500, resulting thumbnail is 256x128.
 *
 * If aspect is ignored (#ETHUMB_THUMB_IGNORE_ASPECT), then image will
 * be distorted to match required thumbnail size. Example: size is
 * 256x256, image is 1000x500, resulting thumbnail is 256x256.
 *
 * If crop is required (#ETHUMB_THUMB_CROP), then image will be
 * cropped so the smallest dimension is not bigger than its specified
 * size (see ethumb_client_size_get()) and the other dimension will
 * overflow, not being visible in the final image. How it will
 * overflow is speficied by ethumb_client_crop_align_set()
 * alignment. Example: size is 256x256, image is 1000x500, crop
 * alignment is 0.5, 0.5, resulting thumbnail is 256x256 with 250
 * pixels from left and 250 pixels from right being lost, that is just
 * the 500x500 central pixels of image will be considered for scaling.
 *
 * @param client the client instance to use. Must @b not be @c
 *        NULL. May be pending connected (can be called before @c
 *        connected_cb)
 * @param a aspect mode identifier, either #ETHUMB_THUMB_KEEP_ASPECT (0),
 *        #ETHUMB_THUMB_IGNORE_ASPECT (1) or #ETHUMB_THUMB_CROP (2).
 */
EAPI void
ethumb_client_aspect_set(Ethumb_Client *client, Ethumb_Thumb_Aspect a)
{
   EINA_SAFETY_ON_NULL_RETURN(client);

   if (!client->old_ethumb_conf)
     client->old_ethumb_conf = ethumb_dup(client->ethumb);
   ethumb_thumb_aspect_set(client->ethumb, a);
}

/**
 * Get current aspect in use for requests.
 *
 * @param client the client instance to use. Must @b not be @c
 *        NULL. May be pending connected (can be called before @c
 *        connected_cb)
 *
 * @return aspect in use for future requests.
 */
EAPI Ethumb_Thumb_Aspect
ethumb_client_aspect_get(const Ethumb_Client *client)
{
   EINA_SAFETY_ON_NULL_RETURN_VAL(client, 0);

   return ethumb_thumb_aspect_get(client->ethumb);
}

/**
 * Configure orientation to use for future requests.
 *
 * Default value is #ETHUMB_THUMB_ORIENT_ORIGINAL: metadata from the file
 * will be used to orient pixel data.
 *
 * @param client the client instance to use. Must @b not be @c
 *        NULL. May be pending connected (can be called before @c
 *        connected_cb)
 * @param o format identifier to use, either #ETHUMB_THUMB_ORIENT_NONE (0),
 *        #ETHUMB_THUMB_ROTATE_90_CW (1), #ETHUMB_THUMB_ROTATE_180 (2),
 *        #ETHUMB_THUMB_ROTATE_90_CCW (3), #ETHUMB_THUMB_FLIP_HORIZONTAL (4),
 *        #ETHUMB_THUMB_FLIP_VERTICAL (5), #ETHUMB_THUMB_FLIP_TRANSPOSE (6),
 *        #ETHUMB_THUMB_FLIP_TRANSVERSE (7) or #ETHUMB_THUMB_ORIENT_ORIGINAL
 *        (8). Default is ORIGINAL.
 */
EAPI void
ethumb_client_orientation_set(Ethumb_Client *client, Ethumb_Thumb_Orientation o)
{
   EINA_SAFETY_ON_NULL_RETURN(client);

   if (!client->old_ethumb_conf)
     client->old_ethumb_conf = ethumb_dup(client->ethumb);
   ethumb_thumb_orientation_set(client->ethumb, o);
}

/**
 * Get current orientation in use for requests.
 *
 * @param client the client instance to use. Must @b not be @c
 *        NULL. May be pending connected (can be called before @c
 *        connected_cb)
 *
 * @return orientation in use for future requests.
 */
EAPI Ethumb_Thumb_Orientation
ethumb_client_orientation_get(const Ethumb_Client *client)
{
   EINA_SAFETY_ON_NULL_RETURN_VAL(client, 0);

   return ethumb_thumb_orientation_get(client->ethumb);
}

/**
 * Configure crop alignment in use for future requests.
 *
 * @param client the client instance to use. Must @b not be @c
 *        NULL. May be pending connected (can be called before @c
 *        connected_cb)
 * @param x horizontal alignment. 0.0 means left side will be visible
 *        or right side is being lost. 1.0 means right side will be
 *        visible or left side is being lost. 0.5 means just center is
 *        visible, both sides will be lost.  Default is 0.5.
 * @param y vertical alignment. 0.0 is top visible, 1.0 is bottom
 *        visible, 0.5 is center visible. Default is 0.5
 */
EAPI void
ethumb_client_crop_align_set(Ethumb_Client *client, float x, float y)
{
   EINA_SAFETY_ON_NULL_RETURN(client);

   if (!client->old_ethumb_conf)
     client->old_ethumb_conf = ethumb_dup(client->ethumb);
   ethumb_thumb_crop_align_set(client->ethumb, x, y);
}

/**
 * Get current crop alignment in use for requests.
 *
 * @param client the client instance to use. Must @b not be @c
 *        NULL. May be pending connected (can be called before @c
 *        connected_cb)
 * @param x where to return horizontal alignment. May be @c NULL.
 * @param y where to return vertical alignment. May be @c NULL.
 */
EAPI void
ethumb_client_crop_align_get(const Ethumb_Client *client, float *x, float *y)
{
   if (x) *x = 0.0;
   if (y) *y = 0.0;
   EINA_SAFETY_ON_NULL_RETURN(client);

   ethumb_thumb_crop_align_get(client->ethumb, x, y);
}

/**
 * Configure quality to be used in thumbnails.
 *
 * @param client the client instance to use. Must @b not be @c
 *        NULL. May be pending connected (can be called before @c
 *        connected_cb)
 * @param quality value from 0 to 100, default is 80. The effect
 *        depends on the format being used, PNG will not use it.
 */
EAPI void
ethumb_client_quality_set(Ethumb_Client *client, int quality)
{
   EINA_SAFETY_ON_NULL_RETURN(client);

   ethumb_thumb_quality_set(client->ethumb, quality);
}

/**
 * Get quality to be used in thumbnails.
 *
 * @param client the client instance to use. Must @b not be @c
 *        NULL. May be pending connected (can be called before @c
 *        connected_cb)
 *
 * @return quality value from 0 to 100, default is 80. The effect
 *         depends on the format being used, PNG will not use it.
 */
EAPI int
ethumb_client_quality_get(const Ethumb_Client *client)
{
   EINA_SAFETY_ON_NULL_RETURN_VAL(client, 0);

   return ethumb_thumb_quality_get(client->ethumb);
}

/**
 * Configure compression level used in requests.
 *
 * @param client the client instance to use. Must @b not be @c
 *        NULL. May be pending connected (can be called before @c
 *        connected_cb)
 * @param compress value from 0 to 9, default is 9. The effect
 *        depends on the format being used, JPEG will not use it.
 */
EAPI void
ethumb_client_compress_set(Ethumb_Client *client, int compress)
{
   EINA_SAFETY_ON_NULL_RETURN(client);

   ethumb_thumb_compress_set(client->ethumb, compress);
}

/**
 * Get compression level used in requests.
 *
 * @param client the client instance to use. Must @b not be @c
 *        NULL. May be pending connected (can be called before @c
 *        connected_cb)
 *
 * @return compress value from 0 to 9, default is 9. The effect
 *         depends on the format being used, JPEG will not use it.
 */
EAPI int
ethumb_client_compress_get(const Ethumb_Client *client)
{
   EINA_SAFETY_ON_NULL_RETURN_VAL(client, 0);

   return ethumb_thumb_compress_get(client->ethumb);
}

/**
 * Set frame to apply to future thumbnails.
 *
 * This will create an edje object that will have image swallowed
 * in. This can be used to simulate Polaroid or wood frames in the
 * generated image. Remeber it is bad to modify the original contents
 * of thumbnails, but sometimes it's useful to have it composited and
 * avoid runtime overhead.
 *
 * @param client the client instance to use. Must @b not be @c
 *        NULL. May be pending connected (can be called before @c
 *        connected_cb)
 * @param file file path to edje.
 * @param group group inside edje to use.
 * @param swallow name of swallow part.
 *
 * @return @c EINA_TRUE on success, @c EINA_FALSE on failure.
 */
EAPI Eina_Bool
ethumb_client_frame_set(Ethumb_Client *client, const char *file, const char *group, const char *swallow)
{
   EINA_SAFETY_ON_NULL_RETURN_VAL(client, 0);

   if (!client->old_ethumb_conf)
     client->old_ethumb_conf = ethumb_dup(client->ethumb);
   return ethumb_frame_set(client->ethumb, file, group, swallow);
}

/**
 * Configure where to store thumbnails in future requests.
 *
 * This value will be used to generate thumbnail paths, that is, it
 * will be used when ethumb_client_thumb_path_set() was not called
 * after last ethumb_client_file_set().
 *
 * Note that this is the base, a category is added to this path as a
 * sub directory. This is not the final directory where files are
 * stored, the thumbnail system will account @b category as well, see
 * ethumb_client_category_set().
 *
 * As other options, this value will only be applied to future
 * requests.
 *
 * @param client the client instance to use. Must @b not be @c
 *        NULL. May be pending connected (can be called before @c
 *        connected_cb)
 * @param path base directory where to store thumbnails. Default is
 *        ~/.thumbnails
 *
 * @see ethumb_client_category_set()
 */
EAPI void
ethumb_client_dir_path_set(Ethumb_Client *client, const char *path)
{
   EINA_SAFETY_ON_NULL_RETURN(client);

   if (!client->old_ethumb_conf)
     client->old_ethumb_conf = ethumb_dup(client->ethumb);
   ethumb_thumb_dir_path_set(client->ethumb, path);
}

/**
 * Get base directory path where to store thumbnails.
 *
 * @param client the client instance to use. Must @b not be @c
 *        NULL. May be pending connected (can be called before @c
 *        connected_cb)
 *
 * @return pointer to internal string with current path. This string
 *         should not be modified or freed.
 *
 * @see ethumb_client_dir_path_set()
 */
EAPI const char *
ethumb_client_dir_path_get(const Ethumb_Client *client)
{
   EINA_SAFETY_ON_NULL_RETURN_VAL(client, NULL);

   return ethumb_thumb_dir_path_get(client->ethumb);
}

/**
 * Category directory to store thumbnails.
 *
 * This value will be used to generate thumbnail paths, that is, it
 * will be used when ethumb_client_thumb_path_set() was not called
 * after last ethumb_client_file_set().
 *
 * This is a sub-directory inside base directory
 * (ethumb_client_dir_path_set()) that creates a namespace to avoid
 * different options resulting in the same file.
 *
 * As other options, this value will only be applied to future
 * requests.
 *
 * @param client the client instance to use. Must @b not be @c
 *        NULL. May be pending connected (can be called before @c
 *        connected_cb)
 * @param category category sub directory to store thumbnail. Default
 *        is either "normal" or "large" for FDO compliant thumbnails
 *        or WIDTHxHEIGHT-ASPECT[-FRAMED]-FORMAT. It can be a string
 *        or @c NULL to use auto generated names.
 *
 * @see ethumb_client_dir_path_set()
 */
EAPI void
ethumb_client_category_set(Ethumb_Client *client, const char *category)
{
   EINA_SAFETY_ON_NULL_RETURN(client);

   if (!client->old_ethumb_conf)
     client->old_ethumb_conf = ethumb_dup(client->ethumb);
   ethumb_thumb_category_set(client->ethumb, category);
}

/**
 * Get category sub-directory  where to store thumbnails.
 *
 * @param client the client instance to use. Must @b not be @c
 *        NULL. May be pending connected (can be called before @c
 *        connected_cb)
 *
 * @return pointer to internal string with current path. This string
 *         should not be modified or freed.
 *
 * @see ethumb_client_category_set()
 */
EAPI const char *
ethumb_client_category_get(const Ethumb_Client *client)
{
   EINA_SAFETY_ON_NULL_RETURN_VAL(client, NULL);

   return ethumb_thumb_category_get(client->ethumb);
}

/**
 * Set the video time (duration) in seconds.
 *
 * @param client the client instance to use. Must @b not be @c
 *        NULL. May be pending connected (can be called before @c
 *        connected_cb)
 * @param t duration (in seconds). Defaults to 3 seconds.
 */
EAPI void
ethumb_client_video_time_set(Ethumb_Client *client, float t)
{
   EINA_SAFETY_ON_NULL_RETURN(client);

   if (!client->old_ethumb_conf)
     client->old_ethumb_conf = ethumb_dup(client->ethumb);
   ethumb_video_time_set(client->ethumb, t);
}

/**
 * Set initial video position to start thumbnailing, in percentage.
 *
 * This is useful to avoid thumbnailing the company/producer logo or
 * movie opening.
 *
 * @param client the client instance to use. Must @b not be @c
 *        NULL. May be pending connected (can be called before @c
 *        connected_cb)
 * @param start initial video positon to thumbnail, in percentage (0.0
 *        to 1.0, inclusive). Defaults to 10% (0.1).
 */
EAPI void
ethumb_client_video_start_set(Ethumb_Client *client, float start)
{
   EINA_SAFETY_ON_NULL_RETURN(client);
   EINA_SAFETY_ON_FALSE_RETURN(start >= 0.0);
   EINA_SAFETY_ON_FALSE_RETURN(start <= 1.0);

   if (!client->old_ethumb_conf)
     client->old_ethumb_conf = ethumb_dup(client->ethumb);
   ethumb_video_start_set(client->ethumb, start);
}

/**
 * Set the video frame interval, in seconds.
 *
 * This is useful for animated thumbnail and will define skip time
 * before going to the next frame. Note that video backends might not
 * be able to precisely skip that amount as it will depend on various
 * factors, including video encoding.
 *
 * Although this seems similar to ethumb_client_video_fps_set(), this
 * one is the time that will be used to seek. The math is simple, for
 * each new frame the video position will be set to:
 * ((video_length * start_time) + (interval * current_frame_number)).
 *
 * @param client the client instance to use. Must @b not be @c
 *        NULL. May be pending connected (can be called before @c
 *        connected_cb)
 * @param interval time between frames, in seconds. Defaults to 0.05
 *        seconds.
 */
EAPI void
ethumb_client_video_interval_set(Ethumb_Client *client, float interval)
{
   EINA_SAFETY_ON_NULL_RETURN(client);

   if (!client->old_ethumb_conf)
     client->old_ethumb_conf = ethumb_dup(client->ethumb);
   ethumb_video_interval_set(client->ethumb, interval);
}

/**
 * Set the number of frames to thumbnail.
 *
 * This is useful for animated thumbnail and will define how many
 * frames the generated file will have.
 *
 * @param client the client instance to use. Must @b not be @c
 *        NULL. May be pending connected (can be called before @c
 *        connected_cb)
 * @param ntimes number of times, must be greater than zero.
 *        Defaults to 3.
 */
EAPI void
ethumb_client_video_ntimes_set(Ethumb_Client *client, unsigned int ntimes)
{
   EINA_SAFETY_ON_NULL_RETURN(client);
   EINA_SAFETY_ON_FALSE_RETURN(ntimes > 0);

   if (!client->old_ethumb_conf)
     client->old_ethumb_conf = ethumb_dup(client->ethumb);
   ethumb_video_ntimes_set(client->ethumb, ntimes);
}

/**
 * Set the number of frames per second to thumbnail the video.
 *
 * This configures the number of times per seconds the thumbnail will
 * use to create thumbnails.
 *
 * Although this is similar to ethumb_client_video_interval_set(), it
 * is the delay used between calling functions thata generates frames,
 * while the other is the time used to skip inside the video.
 *
 * @param client the client instance to use. Must @b not be @c
 *        NULL. May be pending connected (can be called before @c
 *        connected_cb)
 * @param fps number of frames per second to thumbnail. Must be greater
 *        than zero. Defaults to 10.
 */
EAPI void
ethumb_client_video_fps_set(Ethumb_Client *client, unsigned int fps)
{
   EINA_SAFETY_ON_NULL_RETURN(client);
   EINA_SAFETY_ON_FALSE_RETURN(fps > 0);

   if (!client->old_ethumb_conf)
     client->old_ethumb_conf = ethumb_dup(client->ethumb);
   ethumb_video_fps_set(client->ethumb, fps);
}

/**
 * Set the page number to thumbnail in paged documents.
 *
 * @param client the client instance to use. Must @b not be @c
 *        NULL. May be pending connected (can be called before @c
 *        connected_cb)
 * @param page page number, defaults to 0 (first).
 */
EAPI void
ethumb_client_document_page_set(Ethumb_Client *client, unsigned int page)
{
   EINA_SAFETY_ON_NULL_RETURN(client);

   if (!client->old_ethumb_conf)
     client->old_ethumb_conf = ethumb_dup(client->ethumb);
   ethumb_document_page_set(client->ethumb, page);
}

/**
 * Set source file to be thumbnailed.
 *
 * Calling this function has the side effect of resetting values set
 * with ethumb_client_thumb_path_set() or auto-generated with
 * ethumb_client_thumb_exists().
 *
 * @param client the client instance to use. Must @b not be @c
 *        NULL. May be pending connected (can be called before @c
 *        connected_cb)
 * @param path the filesystem path to use. May be @c NULL.
 * @param key the extra argument/key inside @a path to read image
 *        from. This is only used for formats that allow multiple
 *        resources in one file, like EET or Edje (group name).
 *
 * @return @c EINA_TRUE on success, @c EINA_FALSE on failure.
 */
EAPI Eina_Bool
ethumb_client_file_set(Ethumb_Client *client, const char *path, const char *key)
{
   EINA_SAFETY_ON_NULL_RETURN_VAL(client, 0);

   return ethumb_file_set(client->ethumb, path, key);
}

/**
 * Get values set with ethumb_client_file_get()
 *
 * @param client the client instance to use. Must @b not be @c
 *        NULL. May be pending connected (can be called before @c
 *        connected_cb)
 * @param path where to return configured path. May be @c NULL.  If
 *        not @c NULL, then it will be a pointer to a stringshared
 *        instance, but @b no references are added (do it with
 *        eina_stringshare_ref())!
 * @param key where to return configured key. May be @c NULL.If not @c
 *        NULL, then it will be a pointer to a stringshared instance,
 *        but @b no references are added (do it with
 *        eina_stringshare_ref())!
 */
EAPI void
ethumb_client_file_get(Ethumb_Client *client, const char **path, const char **key)
{
   if (path) *path = NULL;
   if (key) *key = NULL;
   EINA_SAFETY_ON_NULL_RETURN(client);

   ethumb_file_get(client->ethumb, path, key);
}

/**
 * Reset previously set file to @c NULL.
 *
 * @param client the client instance to use. Must @b not be @c
 *        NULL. May be pending connected (can be called before @c
 *        connected_cb)
 */
EAPI void
ethumb_client_file_free(Ethumb_Client *client)
{
   EINA_SAFETY_ON_NULL_RETURN(client);

   ethumb_file_free(client->ethumb);
}

/**
 * Set a defined path and key to store the thumbnail.
 *
 * If not explicitly given, the thumbnail path will be auto-generated
 * by ethumb_client_thumb_exists() or server using configured
 * parameters like size, aspect and category.
 *
 * Set these to @c NULL to forget previously given values. After
 * ethumb_client_file_set() these values will be reset to @c NULL.
 *
 * @param client the client instance to use. Must @b not be @c
 *        NULL. May be pending connected (can be called before @c
 *        connected_cb)
 * @param path force generated thumbnail to the exact given path. If
 *        @c NULL, then reverts back to auto-generation.
 * @param key force generated thumbnail to the exact given key. If
 *        @c NULL, then reverts back to auto-generation.
 */
EAPI void
ethumb_client_thumb_path_set(Ethumb_Client *client, const char *path, const char *key)
{
   EINA_SAFETY_ON_NULL_RETURN(client);

   ethumb_thumb_path_set(client->ethumb, path, key);
}

/**
 * Get the configured thumbnail path.
 *
 * This returns the value set with ethumb_client_thumb_path_set() or
 * auto-generated by ethumb_client_thumb_exists() if it was not set.
 *
 * @param client the client instance to use. Must @b not be @c
 *        NULL. May be pending connected (can be called before @c
 *        connected_cb)
 * @param path where to return configured path. May be @c NULL.  If
 *        there was no path configured with
 *        ethumb_client_thumb_path_set() and
 *        ethumb_client_thumb_exists() was not called, then it will
 *        probably return @c NULL. If not @c NULL, then it will be a
 *        pointer to a stringshared instance, but @b no references are
 *        added (do it with eina_stringshare_ref())!
 * @param key where to return configured key. May be @c NULL.  If
 *        there was no key configured with
 *        ethumb_client_thumb_key_set() and
 *        ethumb_client_thumb_exists() was not called, then it will
 *        probably return @c NULL. If not @c NULL, then it will be a
 *        pointer to a stringshared instance, but @b no references are
 *        added (do it with eina_stringshare_ref())!
 */
EAPI void
ethumb_client_thumb_path_get(Ethumb_Client *client, const char **path, const char **key)
{
   if (path) *path = NULL;
   if (key) *key = NULL;
   EINA_SAFETY_ON_NULL_RETURN(client);

   ethumb_thumb_path_get(client->ethumb, path, key);
}

/**
 * Checks whenever file already exists (locally!)
 *
 * This will check locally (not calling server) if thumbnail already
 * exists or not, also calculating the thumbnail path. See
 * ethumb_client_thumb_path_get(). Path must be configured with
 * ethumb_client_file_set() before using it and the last set file will
 * be used!
 *
 * @param client client instance. Must @b not be @c NULL and client
 *        must be configured with ethumb_client_file_set().
 *
 * @return @c NULL on failure, a valid Ethumb_Exists pointer otherwise
 */
EAPI Ethumb_Exists *
ethumb_client_thumb_exists(Ethumb_Client *client, Ethumb_Client_Thumb_Exists_Cb exists_cb, const void *data)
{
   const char *path = NULL;
   Ethumb_Async_Exists *async = NULL;
   Ethumb_Exists *cb = NULL;
   Ecore_Thread *t;

   EINA_SAFETY_ON_NULL_RETURN_VAL(client, NULL);

   ethumb_file_get(client->ethumb, &path, NULL);
   if (!path) goto on_error;

   async = eina_hash_find(_exists_request, path);
   if (!async)
     {
        async = malloc(sizeof (Ethumb_Async_Exists));
        if (!async) goto on_error;

        async->path = eina_stringshare_ref(path);
        async->callbacks = NULL;
        async->dup = ethumb_dup(client->ethumb);

        if (!async->dup) goto on_error;

        cb = malloc(sizeof (Ethumb_Exists));
        if (!cb) goto on_error;

        EINA_REFCOUNT_REF(client);
        cb->client = client;
        cb->dup = ethumb_dup(client->ethumb);
        cb->exists_cb = exists_cb;
        cb->data = data;
        cb->parent = async;

        async->callbacks = eina_list_append(async->callbacks, cb);

        /* spawn a thread here */
        t = ecore_thread_run(_ethumb_client_exists_heavy,
                             _ethumb_client_exists_end,
                             _ethumb_client_exists_end,
                             async);
        if (!t) return NULL;
        async->thread = t;

        eina_hash_direct_add(_exists_request, async->path, async);

        return cb;
     }

   cb = malloc(sizeof (Ethumb_Exists));
   if (!cb)
     {
        async = NULL;
        goto on_error;
     }

   EINA_REFCOUNT_REF(client);
   cb->client = client;
   cb->dup = ethumb_dup(client->ethumb);
   cb->exists_cb = exists_cb;
   cb->data = data;
   cb->parent = async;

   async->callbacks = eina_list_append(async->callbacks, cb);

   return cb;

on_error:
   exists_cb((void *)data, client, NULL, EINA_FALSE);

   if (async)
     {
        eina_stringshare_del(async->path);
        if (async->dup) ethumb_free(async->dup);
        free(async);
     }
   return NULL;
}

/**
 * Cancel an ongoing exists request.
 *
 * @param exists the request to cancel.
 */
EAPI void
ethumb_client_thumb_exists_cancel(Ethumb_Exists *exists)
{
   Ethumb_Async_Exists *async = exists->parent;

   async->callbacks = eina_list_remove(async->callbacks, exists);
   if (eina_list_count(async->callbacks) <= 0)
     ecore_thread_cancel(async->thread);

   ethumb_free(exists->dup);
   EINA_REFCOUNT_UNREF(exists->client) _ethumb_client_free(exists->client);
   free(exists);
}

/**
 * Check if an exists request was cancelled.
 *
 * @param exists the request to check.
 * @result return EINA_TRUE if the request was cancelled.
 */
EAPI Eina_Bool
ethumb_client_thumb_exists_check(Ethumb_Exists *exists)
{
   Ethumb_Async_Exists *async = exists->parent;

   if (!async) return EINA_TRUE;

   if (async->callbacks) return EINA_FALSE;

   return ecore_thread_check(async->thread);
}

/**
 * Ask server to generate thumbnail.
 *
 * This process is asynchronous and will report back from main loop
 * using @a generated_cb. One can cancel this request by calling
 * ethumb_client_generate_cancel() or
 * ethumb_client_generate_cancel_all(), but not that request might be
 * processed by server already and no generated files will be removed
 * if that is the case.
 *
 * This will not check if file already exists, this should be done by
 * explicitly calling ethumb_client_thumb_exists(). That is, this
 * function will override any existing thumbnail.
 *
 * @param client client instance. Must @b not be @c NULL and client
 *        must be connected (after connected_cb is called).
 * @param generated_cb function to report generation results.
 * @param data context argument to give back to @a generated_cb. May
 *        be @c NULL.
 * @param data context to give back to @a generate_cb. May be @c
 *        NULL.
 * @param free_data used to release @a data resources after @a
 *        generated_cb is called or user calls
 *        ethumb_client_disconnect().
 *
 * @return identifier or -1 on error. If -1 is returned (error) then
 *         @a free_data is @b not called!
 *
 * @see ethumb_client_connect()
 * @see ethumb_client_file_set()
 * @see ethumb_client_thumb_exists()
 * @see ethumb_client_generate_cancel()
 * @see ethumb_client_generate_cancel_all()
 */
EAPI int
ethumb_client_generate(Ethumb_Client *client, Ethumb_Client_Generate_Cb generated_cb, const void *data, Eina_Free_Cb free_data)
{
   const char *file, *key, *thumb, *thumb_key;
   int id;
   EINA_SAFETY_ON_NULL_RETURN_VAL(client, -1);
   EINA_SAFETY_ON_FALSE_RETURN_VAL(client->connected, -1);

   ethumb_file_get(client->ethumb, &file, &key);
   if (!file)
     {
        ERR("no file set.");
        return -1;
     }

   ethumb_thumb_path_get(client->ethumb, &thumb, &thumb_key);

   if (client->old_ethumb_conf &&
       ethumb_cmp(client->old_ethumb_conf, client->ethumb))
     {
        ethumb_client_ethumb_setup(client);
        ethumb_free(client->old_ethumb_conf);
        client->old_ethumb_conf = NULL;
     }
   id = _ethumb_client_queue_add(client, file, key, thumb, thumb_key,
                                 generated_cb, data, free_data);
   return id;
}

struct _Ethumb_Client_Async
{
   Ethumb_Exists               *exists;
   Ethumb_Client               *client;
   Ethumb                      *dup;

   Ethumb_Client_Async_Done_Cb  done;
   Ethumb_Client_Async_Error_Cb error;
   const void                  *data;

   int                          id;
};

static Ecore_Idler *idler[2] = { NULL, NULL };
static Eina_List *pending = NULL;
static Eina_List *idle_tasks[2] = { NULL, NULL };

static void
_ethumb_client_async_free(Ethumb_Client_Async *async)
{
   Ethumb_Client *client = async->client;
   ethumb_free(async->dup);
   free(async);
   if (client)
     {
        EINA_REFCOUNT_UNREF(client) _ethumb_client_free(client);
     }
}

static void
_ethumb_client_thumb_finish(void *data,
                            Ethumb_Client *client, int id,
                            const char *file EINA_UNUSED, const char *key EINA_UNUSED,
                            const char *thumb_path, const char *thumb_key,
                            Eina_Bool success)
{
   Ethumb_Client_Async *async = data;

   EINA_SAFETY_ON_FALSE_RETURN(async->id == id);

   if (success)
     {
        async->done(client, thumb_path, thumb_key, (void *)async->data);
     }
   else
     {
        async->error(client, (void *)async->data);
     }

   pending = eina_list_remove(pending, async);
   _ethumb_client_async_free(async);
}

static Eina_Bool
_ethumb_client_thumb_generate_idler(void *data EINA_UNUSED)
{
   Ethumb_Client_Async *async;
   Eina_List *l1, *l2;

   EINA_LIST_FOREACH_SAFE (idle_tasks[1], l1, l2, async)
     {
        Ethumb *tmp;

        idle_tasks[1] = eina_list_remove_list(idle_tasks[1], l1);

        tmp = async->client->ethumb;
        async->client->ethumb = async->dup;

        async->id = ethumb_client_generate(async->client, _ethumb_client_thumb_finish, async, NULL);
        if (async->id == -1)
          {
             async->error(async->client, (void *)async->data);
             async->client->ethumb = tmp;
             _ethumb_client_async_free(async);
             async = NULL;
          }
        else
          {
             async->client->ethumb = tmp;
          }

        if (async)
          pending = eina_list_append(pending, async);

        if (ecore_time_get() - ecore_loop_time_get() > ecore_animator_frametime_get() * 0.5)
          return EINA_TRUE;
     }

   idler[1] = NULL;
   return EINA_FALSE;
}

static void
_ethumb_client_thumb_exists(void *data, Ethumb_Client *client, Ethumb_Exists *request, Eina_Bool exists)
{
   Ethumb_Client_Async *async = data;

   if (request == NULL)
     return;

   EINA_SAFETY_ON_FALSE_RETURN(async->exists == request);

   async->exists = NULL;
   pending = eina_list_remove(pending, async);

   if (exists)
     {
        const char *thumb_path;
        const char *thumb_key;

        ethumb_client_thumb_path_get(client, &thumb_path, &thumb_key);
        async->done(client, thumb_path, thumb_key, (void *)async->data);
        _ethumb_client_async_free(async);
     }
   else
     {
        idle_tasks[1] = eina_list_append(idle_tasks[1], async);

        if (!idler[1])
          idler[1] = ecore_idler_add(_ethumb_client_thumb_generate_idler, NULL);
     }
}

static Eina_Bool
_ethumb_client_thumb_exists_idler(void *data EINA_UNUSED)
{
   Ethumb_Client_Async *async;
   Eina_List *l1, *l2;

   EINA_LIST_FOREACH_SAFE (idle_tasks[0], l1, l2, async)
     {
        Ethumb *tmp;

        idle_tasks[0] = eina_list_remove_list(idle_tasks[0], l1);

        tmp = async->client->ethumb;
        async->client->ethumb = async->dup;

        async->exists = ethumb_client_thumb_exists(async->client, _ethumb_client_thumb_exists, async);
        if (!async->exists)
          {
             async->error(async->client, (void *)async->data);
             async->client->ethumb = tmp;
             _ethumb_client_async_free(async);
             continue;
          }

        async->client->ethumb = tmp;

        pending = eina_list_append(pending, async);

        if (ecore_time_get() - ecore_loop_time_get() > ecore_animator_frametime_get() * 0.5)
          return EINA_TRUE;
     }

   idler[0] = NULL;
   return EINA_FALSE;
}

EAPI Ethumb_Client_Async *
ethumb_client_thumb_async_get(Ethumb_Client *client,
                              Ethumb_Client_Async_Done_Cb done,
                              Ethumb_Client_Async_Error_Cb error,
                              const void *data)
{
   Ethumb_Client_Async *async;

   EINA_SAFETY_ON_NULL_RETURN_VAL(client, NULL);

   async = malloc(sizeof (Ethumb_Client_Async));
   if (!async)
     {
        error(client, (void *)data);
        return NULL;
     }

   EINA_REFCOUNT_REF(client);
   async->client = client;
   async->dup = ethumb_dup(client->ethumb);
   async->done = done;
   async->error = error;
   async->data = data;
   async->exists = NULL;
   async->id = -1;

   idle_tasks[0] = eina_list_append(idle_tasks[0], async);

   if (!idler[0])
     idler[0] = ecore_idler_add(_ethumb_client_thumb_exists_idler, NULL);

   return async;
}

EAPI void
ethumb_client_thumb_async_cancel(Ethumb_Client *client, Ethumb_Client_Async *request)
{
   const char *path;

   EINA_SAFETY_ON_NULL_RETURN(client);
   EINA_SAFETY_ON_NULL_RETURN(request);

   ethumb_file_get(request->dup, &path, NULL);

   if (request->exists)
     {
        ethumb_client_thumb_exists_cancel(request->exists);
        request->exists = NULL;

        pending = eina_list_remove(pending, request);
     }
   else if (request->id != -1)
     {
        Ethumb *tmp = request->client->ethumb;
        request->client->ethumb = request->dup;

        ethumb_client_generate_cancel(request->client, request->id, NULL, NULL, NULL);

        request->client->ethumb = tmp;

        pending = eina_list_remove(pending, request);
     }
   else
     {
        idle_tasks[0] = eina_list_remove(idle_tasks[0], request);
        idle_tasks[1] = eina_list_remove(idle_tasks[1], request);
     }

   _ethumb_client_async_free(request);
}