/* ***** BEGIN LICENSE BLOCK ***** * Version: MPL 1.1/GPL 2.0/LGPL 2.1 * * The contents of this file are subject to the Mozilla Public License Version * 1.1 (the "License"); you may not use this file except in compliance with * the License. You may obtain a copy of the License at * http://www.mozilla.org/MPL/ * * Software distributed under the License is distributed on an "AS IS" basis, * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License * for the specific language governing rights and limitations under the * License. * * The Original Code is libguac. * * The Initial Developer of the Original Code is * Michael Jumper. * Portions created by the Initial Developer are Copyright (C) 2010 * the Initial Developer. All Rights Reserved. * * Contributor(s): * * Alternatively, the contents of this file may be used under the terms of * either the GNU General Public License Version 2 or later (the "GPL"), or * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"), * in which case the provisions of the GPL or the LGPL are applicable instead * of those above. If you wish to allow use of your version of this file only * under the terms of either the GPL or the LGPL, and not to allow others to * use your version of this file under the terms of the MPL, indicate your * decision by deleting the provisions above and replace them with the notice * and other provisions required by the GPL or the LGPL. If you do not delete * the provisions above, a recipient may use your version of this file under * the terms of any one of the MPL, the GPL or the LGPL. * * ***** END LICENSE BLOCK ***** */ #ifndef _GUAC_CLIENT_H #define _GUAC_CLIENT_H #include #include "socket.h" #include "protocol.h" /** * Provides functions and structures required for defining (and handling) a proxy client. * * @file client.h */ /** * String prefix which begins the library filename of all client plugins. */ #define GUAC_PROTOCOL_LIBRARY_PREFIX "libguac-client-" /** * String suffix which ends the library filename of all client plugins. */ #define GUAC_PROTOCOL_LIBRARY_SUFFIX ".so" /** * The maximum number of characters (COUNTING NULL TERMINATOR) to allow * for protocol names within the library filename of client plugins. */ #define GUAC_PROTOCOL_NAME_LIMIT 256 /** * The maximum number of characters (INCLUDING NULL TERMINATOR) that a * character array containing the concatenation of the library prefix, * protocol name, and suffix can contain, assuming the protocol name is * limited to GUAC_PROTOCOL_NAME_LIMIT characters. */ #define GUAC_PROTOCOL_LIBRARY_LIMIT ( \ \ sizeof(GUAC_PROTOCOL_LIBRARY_PREFIX) - 1 /* "libguac-client-" */ \ + GUAC_PROTOCOL_NAME_LIMIT - 1 /* [up to 256 chars] */ \ + sizeof(GUAC_PROTOCOL_LIBRARY_SUFFIX) - 1 /* ".so" */ \ + 1 /* NULL terminator */ \ \ ) typedef struct guac_client guac_client; typedef struct guac_client_plugin guac_client_plugin; /** * Handler for server messages (where "server" refers to the server that * the proxy client is connected to). */ typedef int guac_client_handle_messages(guac_client* client); /** * Handler for Guacamole mouse events. */ typedef int guac_client_mouse_handler(guac_client* client, int x, int y, int button_mask); /** * Handler for Guacamole key events. */ typedef int guac_client_key_handler(guac_client* client, int keysym, int pressed); /** * Handler for Guacamole clipboard events. */ typedef int guac_client_clipboard_handler(guac_client* client, char* copied); /** * Handler for freeing up any extra data allocated by the client * implementation. */ typedef int guac_client_free_handler(guac_client* client); /** * Handler for logging messages */ typedef void guac_client_log_handler(guac_client* client, const char* format, va_list args); /** * Handler which should initialize the given guac_client. */ typedef int guac_client_init_handler(guac_client* client, int argc, char** argv); /** * Handler which will be called whenever a resource has been accepted by the * client. */ typedef int guac_client_accept_handler(guac_client* client, guac_resource* resource, const char* mimetype); /** * Handler which will be called whenever a resource has been rejected by the * client. */ typedef int guac_client_reject_handler(guac_client* client, guac_resource* resource); /* * NOTE: The data and end instructions are currently implemented client-side * only, and allocation of resources must ALWAYS be server-side. * * Each resource is mono-directional. Two resources must be allocated for * bidirectional communication. * * Exposure of client-side resources to the server will be accomplished * over the same protocol (resource -> accept/reject -> data -> end). The * mono-directional nature of resources will allow the index spaces of * client and server resources to be independent. */ /** * The flag set in the mouse button mask when the left mouse button is down. */ #define GUAC_CLIENT_MOUSE_LEFT 0x01 /** * The flag set in the mouse button mask when the middle mouse button is down. */ #define GUAC_CLIENT_MOUSE_MIDDLE 0x02 /** * The flag set in the mouse button mask when the right mouse button is down. */ #define GUAC_CLIENT_MOUSE_RIGHT 0x04 /** * The flag set in the mouse button mask when the mouse scrollwheel is scrolled * up. Note that mouse scrollwheels are actually sets of two buttons. One * button is pressed and released for an upward scroll, and the other is * pressed and released for a downward scroll. Some mice may actually implement * these as separate buttons, not a wheel. */ #define GUAC_CLIENT_MOUSE_SCROLL_UP 0x08 /** * The flag set in the mouse button mask when the mouse scrollwheel is scrolled * down. Note that mouse scrollwheels are actually sets of two buttons. One * button is pressed and released for an upward scroll, and the other is * pressed and released for a downward scroll. Some mice may actually implement * these as separate buttons, not a wheel. */ #define GUAC_CLIENT_MOUSE_SCROLL_DOWN 0x10 /** * The minimum number of buffers to create before allowing free'd buffers to * be reclaimed. In the case a protocol rapidly creates, uses, and destroys * buffers, this can prevent unnecessary reuse of the same buffer (which * would make draw operations unnecessarily synchronous). */ #define GUAC_BUFFER_POOL_INITIAL_SIZE 1024 /** * Possible current states of the Guacamole client. Currently, the only * two states are GUAC_CLIENT_RUNNING and GUAC_CLIENT_STOPPING. */ typedef enum guac_client_state { /** * The state of the client from when it has been allocated by the main * daemon until it is killed or disconnected. */ GUAC_CLIENT_RUNNING, /** * The state of the client when a stop has been requested, signalling the * I/O threads to shutdown. */ GUAC_CLIENT_STOPPING } guac_client_state; /** * A handle to a client plugin, containing enough information about the * plugin to complete the initial protocol handshake and instantiate a new * client supporting the protocol provided by the client plugin. */ struct guac_client_plugin { /** * Reference to dlopen'd client plugin. */ void* __client_plugin_handle; /** * Reference to the init handler of this client plugin. This * function will be called when the client plugin is started. */ guac_client_init_handler* init_handler; /** * NULL-terminated array of all arguments accepted by this client * plugin, in order. The values of these arguments will be passed * to the init_handler if the client plugin is started. */ const char** args; }; /** * 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 guac_socket 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 guac_socket * structure is used only to communicate conveniently with the Guacamole * web-client. */ guac_socket* socket; /** * The current state of the client. When the client is first allocated, * this will be initialized to GUAC_CLIENT_RUNNING. It will remain at * GUAC_CLIENT_RUNNING until an event occurs which requires the client to * shutdown, at which point the state becomes GUAC_CLIENT_STOPPING. */ guac_client_state state; /** * The time (in milliseconds) of receipt of the last sync message from * the client. */ guac_timestamp last_received_timestamp; /** * The time (in milliseconds) that the last sync message was sent to the * client. */ guac_timestamp last_sent_timestamp; /** * 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 * int handle_messages(guac_client* client); * * int guac_client_init(guac_client* client, int argc, char** argv) { * 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: * * * * * * * * *
Button Value
Left 1
Middle 2
Right 4
Scrollwheel Up 8
Scrollwheel Down16
* Example: * @code * int mouse_handler(guac_client* client, int x, int y, int button_mask); * * int guac_client_init(guac_client* client, int argc, char** argv) { * 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 * int key_handler(guac_client* client, int keysym, int pressed); * * int guac_client_init(guac_client* client, int argc, char** argv) { * 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 * int clipboard_handler(guac_client* client, char* copied); * * int guac_client_init(guac_client* client, int argc, char** argv) { * 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. * * Note that this handler will NOT be called if the client's * guac_client_init() function fails. * * Implement this handler if you store data inside the client. * * Example: * @code * int free_handler(guac_client* client); * * int guac_client_init(guac_client* client, int argc, char** argv) { * client->free_handler = free_handler; * } * @endcode */ guac_client_free_handler* free_handler; /** * Handler for logging informational messages. This handler will be called * via guac_client_log_info() when the client needs to log information. * * In general, only programs loading the client should implement this * handler, as those are the programs that would provide the logging * facilities. * * Client implementations should expect these handlers to already be * set. * * Example: * @code * void log_handler(guac_client* client, const char* format, va_list args); * * void function_of_daemon() { * * guac_client* client = [pass log_handler to guac_client_plugin_get_client()]; * * } * @endcode */ guac_client_log_handler* log_info_handler; /** * Handler for logging error messages. This handler will be called * via guac_client_log_error() when the client needs to log an error. * * In general, only programs loading the client should implement this * handler, as those are the programs that would provide the logging * facilities. * * Client implementations should expect these handlers to already be * set. * * Example: * @code * void log_handler(guac_client* client, const char* format, va_list args); * * void function_of_daemon() { * * guac_client* client = [pass log_handler to guac_client_plugin_get_client()]; * * } * @endcode */ guac_client_log_handler* log_error_handler; /** * The index of the next available buffer. */ int __next_buffer_index; /** * The head pointer of the list of all available (allocated but not used) * buffers. */ guac_layer* __available_buffers; /** * Pointer to the last buffer in the list of all available buffers. */ guac_layer* __last_available_buffer; /** * The index of the next available layer. */ int __next_layer_index; /** * The head pointer of the list of all available (allocated but not used) * layers. */ guac_layer* __available_layers; /** * Pointer to the last layer in the list of all available layers. */ guac_layer* __last_available_layer; /** * The head pointer of the list of all allocated layers, regardless of use * status. */ guac_layer* __all_layers; }; /** * Open the plugin which provides support for the given protocol, if it * exists. * * @param protocol The name of the protocol to retrieve the client plugin * for. * @return The client plugin supporting the given protocol, or NULL if * an error occurs or no such plugin exists. */ guac_client_plugin* guac_client_plugin_open(const char* protocol); /** * Close the given plugin, releasing all associated resources. This function * must be called after use of a client plugin is finished. * * @param plugin The client plugin to close. * @return Zero on success, non-zero if an error occurred while releasing * the resources associated with the plugin. */ int guac_client_plugin_close(guac_client_plugin* plugin); /** * Initializes the given guac_client using the initialization routine provided * by the given guac_client_plugin. * * @param plugin The client plugin to use to initialize the new client. * @param client The guac_client to initialize. * @param argc The number of arguments being passed to the client. * @param argv All arguments to be passed to the client. * @return Zero if initialization was successful, non-zero otherwise. */ int guac_client_plugin_init_client(guac_client_plugin* plugin, guac_client* client, int argc, char** argv); /** * Returns a new, barebones guac_client. This new guac_client has no handlers * set, but is otherwise usable. * * @return A pointer to the new client. */ guac_client* guac_client_alloc(); /** * Free all resources associated with the given client. * * @param client The proxy client to free all reasources of. */ void guac_client_free(guac_client* client); /** * Call the appropriate handler defined by the given client for the given * instruction. A comparison is made between the instruction opcode and the * initial handler lookup table defined in client-handlers.c. The intial * handlers will in turn call the client's handler (if defined). * * @param client The proxy client whose handlers should be called. * @param instruction The instruction to pass to the proxy client via the * appropriate handler. */ int guac_client_handle_instruction(guac_client* client, guac_instruction* instruction); /** * Allocates a new buffer (invisible layer). An arbitrary index is * automatically assigned if no existing buffer is available for use. * * @param client The proxy client to allocate the buffer for. * @return The next available buffer, or a newly allocated buffer. */ guac_layer* guac_client_alloc_buffer(guac_client* client); /** * Allocates a new layer. An arbitrary index is automatically assigned * if no existing layer is available for use. * * @param client The proxy client to allocate the layer buffer for. * @return The next available layer, or a newly allocated layer. */ guac_layer* guac_client_alloc_layer(guac_client* client); /** * Returns the given buffer to the pool of available buffers, such that it * can be reused by any subsequent call to guac_client_allow_buffer(). * * @param client The proxy client to return the buffer to. * @param layer The buffer to return to the pool of available buffers. */ void guac_client_free_buffer(guac_client* client, guac_layer* layer); /** * Returns the given layer to the pool of available layers, such that it * can be reused by any subsequent call to guac_client_allow_layer(). * * @param client The proxy client to return the layer to. * @param layer The buffer to return to the pool of available layer. */ void guac_client_free_layer(guac_client* client, guac_layer* layer); /** * Allocates a new resource. An arbitrary index is automatically assigned * if no existing resource index is available for use. * * @param client The proxy client to allocate the resource for. * @return The next available resource, or a newly allocated resource. */ guac_resource* guac_client_alloc_resource(guac_client* client); /** * Frees an existing resource, re-adding it to the client's resource * pool, such that it can be reused by a subsequent call to * guac_client_alloc_resource(). * * @param client The proxy client to free the resource for. * @oaran resource The resource to return to the resource pool. */ void guac_client_free_resource(guac_client* client, guac_resource* resource); /** * Logs an informational message in the log used by the given client. The * logger used will normally be defined by guacd (or whichever program loads * the proxy client) by setting the logging handlers of the client when it is * loaded. * * @param client The proxy client to log an informational message for. * @param format A printf-style format string to log. * @param ... Arguments to use when filling the format string for printing. */ void guac_client_log_info(guac_client* client, const char* format, ...); /** * Logs an error message in the log used by the given client. The logger * used will normally be defined by guacd (or whichever program loads the * proxy client) by setting the logging handlers of the client when it is * loaded. * * @param client The proxy client to log an error for. * @param format A printf-style format string to log. * @param ... Arguments to use when filling the format string for printing. */ void guac_client_log_error(guac_client* client, const char* format, ...); /** * Logs an informational message in the log used by the given client. The * logger used will normally be defined by guacd (or whichever program loads * the proxy client) by setting the logging handlers of the client when it is * loaded. * * @param client The proxy client to log an informational message for. * @param format A printf-style format string to log. * @param ap The va_list containing the arguments to be used when filling the * format string for printing. */ void vguac_client_log_info(guac_client* client, const char* format, va_list ap); /** * Logs an error message in the log used by the given client. The logger * used will normally be defined by guacd (or whichever program loads the * proxy client) by setting the logging handlers of the client when it is * loaded. * * @param client The proxy client to log an error for. * @param format A printf-style format string to log. * @param ap The va_list containing the arguments to be used when filling the * format string for printing. */ void vguac_client_log_error(guac_client* client, const char* format, va_list ap); /** * Signals the given client to stop gracefully. This is a completely * cooperative signal, and can be ignored by the client or the hosting * daemon. * * @param client The proxy client to signal to stop. */ void guac_client_stop(guac_client* client); /** * The default Guacamole client layer, layer 0. */ extern const guac_layer* GUAC_DEFAULT_LAYER; #endif