guacamole-client/guacamole/libguac/include/client.h

/*
 *  Guacamole - Clientless Remote Desktop
 *  Copyright (C) 2010  Michael Jumper
 *
 *  This program is free software: you can redistribute it and/or modify
 *  it under the terms of the GNU Affero General Public License as published by
 *  the Free Software Foundation, either version 3 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 Affero General Public License for more details.
 *
 *  You should have received a copy of the GNU Affero General Public License
 *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

#ifndef _CLIENT_H
#define _CLIENT_H

#include <png.h>

#include "guacio.h"

typedef struct guac_client guac_client;

typedef void guac_client_handle_messages(guac_client* client);
typedef void guac_client_mouse_handler(guac_client* client, int x, int y, int button_mask);
typedef void guac_client_key_handler(guac_client* client, int keysym, int pressed);
typedef void guac_client_clipboard_handler(guac_client* client, char* copied);
typedef void guac_client_free_handler(void* client);

/**
 * Guacamole proxy client.
 *
 * Represents a Guacamole proxy client (the client which communicates to
 * a server on behalf of Guacamole, on behalf of the web-client).
 */
struct guac_client {

    /**
     * The GUACIO structure to be used to communicate with the web-client. It is
     * expected that the implementor of any Guacamole proxy client will provide
     * their own mechanism of I/O for their protocol. The GUACIO structure is
     * used only to communicate conveniently with the Guacamole web-client.
     */
    GUACIO* io;

    /**
     * Arbitrary reference to proxy client-specific data. Implementors of a
     * Guacamole proxy client can store any data they want here, which can then
     * be retrieved as necessary in the message handlers.
     */
    void* data;

    /**
     * Handler for server messages. If set, this function will be called
     * occasionally by the Guacamole proxy to give the client a chance to
     * handle messages from whichever server it is connected to.
     *
     * Example:
     * @code
     *     void handle_messages(guac_client* client);
     *
     *     void guac_client_init(guac_client* client) {
     *         client->handle_messages = handle_messages;
     *     }
     * @endcode
     */
    guac_client_handle_messages* handle_messages;

    /**
     * Handler for mouse events sent by the Gaucamole web-client.
     *
     * The handler takes the integer mouse X and Y coordinates, as well as
     * a button mask containing the bitwise OR of all button values currently
     * being pressed. Those values are:
     *
     * <table>
     *     <tr><th>Button</th>          <th>Value</th></tr>
     *     <tr><td>Left</td>            <td>1</td></tr>
     *     <tr><td>Middle</td>          <td>2</td></tr>
     *     <tr><td>Right</td>           <td>4</td></tr>
     *     <tr><td>Scrollwheel Up</td>  <td>8</td></tr>
     *     <tr><td>Scrollwheel Down</td><td>16</td></tr>
     * </table>

     * Example:
     * @code
     *     void mouse_handler(guac_client* client, int x, int y, int button_mask);
     *
     *     void guac_client_init(guac_client* client) {
     *         client->mouse_handler = mouse_handler;
     *     }
     * @endcode
     */
    guac_client_mouse_handler* mouse_handler;

    /**
     * Handler for key events sent by the Guacamole web-client.
     *
     * The handler takes the integer X11 keysym associated with the key
     * being pressed/released, and an integer representing whether the key
     * is being pressed (1) or released (0).
     *
     * Example:
     * @code
     *     void key_handler(guac_client* client, int keysym, int pressed);
     *
     *     void guac_client_init(guac_client* client) {
     *         client->key_handler = key_handler;
     *     }
     * @endcode
     */
    guac_client_key_handler* key_handler;

    /**
     * Handler for clipboard events sent by the Guacamole web-client. This
     * handler will be called whenever the web-client sets the data of the
     * clipboard.
     *
     * This handler takes a single string which contains the text which
     * has been set in the clipboard. This text is already unescaped from
     * the Guacamole escaped version sent within the clipboard message
     * in the protocol.
     *
     * Example:
     * @code
     *     void clipboard_handler(guac_client* client, char* copied);
     *
     *     void guac_client_init(guac_client* client) {
     *         client->clipboard_handler = clipboard_handler;
     *     }
     * @endcode
     */
    guac_client_clipboard_handler* clipboard_handler;

    /**
     * Handler for freeing data when the client is being unloaded.
     *
     * This handler will be called when the client needs to be unloaded
     * by the proxy, and any data allocated by the proxy client should be
     * freed.
     *
     * Implement this handler if you store data inside the client.
     *
     * Example:
     * @code
     *     void free_handler(guac_client* client);
     *
     *     void guac_client_init(guac_client* client) {
     *         client->free_handler = free_handler;
     *     }
     * @endcode
     */
    guac_client_free_handler* free_handler;

};

typedef void guac_client_init_handler(guac_client* client, const char* hostname, int port);
guac_client* guac_get_client(int client_fd, guac_client_init_handler* client_init, const char* hostname, int port);
void guac_start_client(guac_client* client);
void guac_free_client(guac_client* client);
png_byte** guac_alloc_png_buffer(int w, int h, int bpp);
void guac_free_png_buffer(png_byte** png_buffer, int h);

#endif