diff --git a/common/jack/session.h b/common/jack/session.h new file mode 100644 index 00000000..8c13bfa9 --- /dev/null +++ b/common/jack/session.h @@ -0,0 +1,229 @@ +/* + Copyright (C) 2001 Paul Davis + Copyright (C) 2004 Jack O'Quin + Copyright (C) 2010 Torben Hohn + + This program 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 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 Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public License + along with this program; if not, write to the Free Software + Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. + +*/ + +#ifndef __jack_session_h__ +#define __jack_session_h__ + +#ifdef __cplusplus +extern "C" { +#endif + +#include +#include + +/** + * @defgroup SessionClientFunctions Session API for clients. + * @{ + */ + + +/** + * session event types. + * + * if a client cant save templates, i might just do a normal save. + * + * the rationale, why there is no quit without save, is that a client + * might refuse to quit when it has unsaved data. + * however some other clients might have already quit. + * this results in too much confusion, so we just dont support that. + * the session manager can check, if the saved state is different from a previous + * save, and just remove the saved stuff. + * + * (an inquiry function, whether a quit is ok, followed by a quit event + * would have a race) + */ +enum JackSessionEventType { + JackSessionSave = 1, + JackSessionSaveAndQuit = 2, + JackSessionSaveTemplate = 3 +}; + +typedef enum JackSessionEventType jack_session_event_type_t; + +enum JackSessionFlags { + /** + * an error occured while saving. + */ + JackSessionSaveError = 0x01, + + /** + * this reply indicates that a client is part of a multiclient application. + * the command reply is left empty. but the session manager should still + * consider this client part of a session. it will come up due to invocation of another + * client. + */ + JackSessionChildClient = 0x02 +}; + +typedef enum JackSessionFlags jack_session_flags_t; + +struct _jack_session_event { + /** + * the actual type of this session event. + */ + jack_session_event_type_t type; + + /** + * session_directory with trailing separator + * this is per client. so the client can do whatever it likes in here. + */ + const char *session_dir; + + /** + * client_uuid which must be specified to jack_client_open on session reload. + * client can specify it in the returned commandline as an option, or just save it + * with the state file. + */ + const char *client_uuid; + + /** + * the command_line is the reply of the client. + * it specifies in a platform dependent way, how the client must be restarted upon session reload. + * + * probably it should contain ${SESSION_DIR} instead of the actual session dir. + * this would basically make the session dir moveable. + * + * ownership of the memory is handed to jack. + * initially set to NULL by jack; + */ + char *command_line; + + /** + * flags to be set by the client. normally left 0. + */ + jack_session_flags_t flags; +}; + +typedef struct _jack_session_event jack_session_event_t; + +/** + * Prototype for the client supplied function that is called + * whenever a session notification is sent via jack_session_notify(). + * + * The session_id must be passed to jack_client_open on session reload (this can be + * done by specifying it somehow on the returned command line). + * + * @param event the event_structure. + * @param arg pointer to a client supplied structure + */ +typedef void (*JackSessionCallback)(jack_session_event_t *event, void *arg); + +/** + * Tell the JACK server to call @a save_callback the session handler wants + * to save. + * + * @return 0 on success, otherwise a non-zero error code + */ +int jack_set_session_callback(jack_client_t *client, + JackSessionCallback session_callback, + void *arg) JACK_WEAK_EXPORT; + +/** + * reply to a session_event + * + * this can either be called directly from the callback, or later from a different thread. + * so its possible to just stick the event pointer into a pipe and execute the save code + * from the gui thread. + * + * @return 0 on success, otherwise a non-zero error code + */ + +int jack_session_reply( jack_client_t *client, jack_session_event_t *event ) JACK_WEAK_EXPORT; + + +/** + * free memory used by a jack_session_event_t + * this also frees the memory used by the command_line pointer. + * if its non NULL. + */ + +void jack_session_event_free (jack_session_event_t *event); + +/*@}*/ + + +/** + * @defgroup JackSessionManagerAPI this API is intended for a sessionmanager. + * this API could be server specific. if we dont reach consensus here, + * we can just drop it. + * i know its a bit clumsy. + * but this api isnt required to be as stable as the client api. + * @{ + */ + +typedef struct { + const char *uuid; + const char *client_name; + const char *command; + jack_session_flags_t flags; +} jack_session_command_t; + +/** + * send a save or quit event, to all clients listening for session + * callbacks. the returned strings of the clients are accumulated and + * returned as an array of jack_session_command_t. + * its terminated by ret[i].uuid == NULL + * target == NULL means send to all interested clients. otherwise a clientname + */ + +jack_session_command_t *jack_session_notify (jack_client_t* client, + const char *target, + jack_session_event_type_t type, + const char *path ) JACK_WEAK_EXPORT; + +/** + * free the memory allocated by a session command. + */ + +void jack_session_commands_free (jack_session_command_t *cmds) JACK_WEAK_EXPORT; + +/** + * get the sessionid for a client name. + * the sessionmanager needs this to reassociate a client_name to the session_id. + */ + +char *jack_get_uuid_for_client_name( jack_client_t *client, const char *client_name ) JACK_WEAK_EXPORT; + +/** + * get the client name for a session_id. + * in order to snapshot the graph connections, the sessionmanager needs to map + * session_ids to client names. + */ + +char *jack_get_client_name_by_uuid( jack_client_t *client, const char *client_uuid ) JACK_WEAK_EXPORT; + +/** + * reserve a client name and associate it to a uuid. + * when a client later call jack_client_open() and specifies the uuid, + * jackd will assign the reserved name. + * this allows a session manager to know in advance under which client name + * its managed clients will appear. + * + * @return 0 on success, otherwise a non-zero error code + */ + +int +jack_reserve_client_name( jack_client_t *client, const char *name, const char *uuid ) JACK_WEAK_EXPORT; + +#ifdef __cplusplus +} +#endif +#endif