guacamole-spice-protocol/libguac/include/client.h
2012-10-22 14:37:41 -07:00

632 lines
21 KiB
C

/* ***** 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 <stdarg.h>
#include "instruction.h"
#include "layer.h"
#include "pool.h"
#include "socket.h"
#include "stream.h"
#include "timestamp.h"
/**
* Provides functions and structures required for defining (and handling) a proxy client.
*
* @file client.h
*/
typedef struct guac_client guac_client;
/**
* 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 Guacamole screen size events.
*/
typedef int guac_client_size_handler(guac_client* client,
int width, int height);
/**
* Handler for Guacamole audio format events.
*/
typedef int guac_client_audio_handler(guac_client* client, char* mimetype);
/**
* Handler for Guacamole video format events.
*/
typedef int guac_client_video_handler(guac_client* client, char* mimetype);
/**
* 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);
/**
* 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;
/**
* Information exposed by the remote client during the connection handshake
* which can be used by a client plugin.
*/
typedef struct guac_client_info {
/**
* The number of pixels the remote client requests for the display width.
* This need not be honored by a client plugin implementation, but if the
* underlying protocol of the client plugin supports dynamic sizing of the
* screen, honoring the display size request is recommended.
*/
int optimal_width;
/**
* The number of pixels the remote client requests for the display height.
* This need not be honored by a client plugin implementation, but if the
* underlying protocol of the client plugin supports dynamic sizing of the
* screen, honoring the display size request is recommended.
*/
int optimal_height;
/**
* NULL-terminated array of client-supported audio mimetypes. If the client
* does not support audio at all, this will be NULL.
*/
char* audio_mimetypes;
/**
* NULL-terminated array of client-supported video mimetypes. If the client
* does not support video at all, this will be NULL.
*/
char* video_mimetypes;
} guac_client_info;
/**
* 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;
/**
* Information structure containing properties exposed by the remote
* client during the initial handshake process.
*/
guac_client_info info;
/**
* 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:
*
* <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
* 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 size events sent by the Guacamole web-client.
*
* The handler takes an integer width and integer height, representing
* the current visible screen area of the client.
*
* Example:
* @code
* int size_handler(guac_client* client, int width, int height);
*
* int guac_client_init(guac_client* client, int argc, char** argv) {
* client->size_handler = size_handler;
* }
* @endcode
*/
guac_client_size_handler* size_handler;
/**
* Handler for audio format events sent by the Guacamole web-client.
*
* The handler takes the mimetype of the audio format being advertised
* as supported by the client.
*
* Example:
* @code
* int audio_handler(guac_client* client, char* mimetype);
*
* int guac_client_init(guac_client* client, int argc, char** argv) {
* client->audio_handler = audio_handler;
* }
* @endcode
*/
guac_client_audio_handler* audio_handler;
/**
* Handler for video format events sent by the Guacamole web-client.
*
* The handler takes the mimetype of the video format being advertised
* as supported by the client.
*
* Example:
* @code
* int video_handler(guac_client* client, char* mimetype);
*
* int guac_client_init(guac_client* client, int argc, char** argv) {
* client->video_handler = video_handler;
* }
* @endcode
*/
guac_client_video_handler* video_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;
/**
* Pool of buffer indices. Buffers are simply layers with negative indices.
* Note that because guac_pool always gives non-negative indices starting
* at 0, the output of this guac_pool will be adjusted.
*/
guac_pool* __buffer_pool;
/**
* Pool of layer indices. Note that because guac_pool always gives
* non-negative indices starting at 0, the output of this guac_pool will
* be adjusted.
*/
guac_pool* __layer_pool;
/**
* Pool of stream indices.
*/
guac_pool* __stream_pool;
};
/**
* 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);
/**
* 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);
/**
* 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 stream. An arbitrary index is automatically assigned
* if no previously-allocated stream is available for use.
*
* @param client The proxy client to allocate the layer buffer for.
* @return The next available stream, or a newly allocated stream.
*/
guac_stream* guac_client_alloc_stream(guac_client* client);
/**
* Returns the given stream to the pool of available streams, such that it
* can be reused by any subsequent call to guac_client_alloc_stream().
*
* @param client The proxy client to return the buffer to.
* @param stream The stream to return to the pool of available stream.
*/
void guac_client_free_stream(guac_client* client, guac_stream* stream);
/**
* The default Guacamole client layer, layer 0.
*/
extern const guac_layer* GUAC_DEFAULT_LAYER;
#endif