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| -rw-r--r-- | pipewire-jack/jack/midiport.h | 197 |
1 files changed, 197 insertions, 0 deletions
diff --git a/pipewire-jack/jack/midiport.h b/pipewire-jack/jack/midiport.h new file mode 100644 index 0000000..0ae5e79 --- /dev/null +++ b/pipewire-jack/jack/midiport.h @@ -0,0 +1,197 @@ +/* + Copyright (C) 2004 Ian Esten + + 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_MIDIPORT_H +#define __JACK_MIDIPORT_H + +#ifdef __cplusplus +extern "C" { +#endif + +#include <jack/weakmacros.h> +#include <jack/types.h> +#include <stdlib.h> + + +/** Type for raw event data contained in @ref jack_midi_event_t. */ +typedef unsigned char jack_midi_data_t; + + +/** A Jack MIDI event. */ +typedef struct _jack_midi_event +{ + jack_nframes_t time; /**< Sample index at which event is valid */ + size_t size; /**< Number of bytes of data in \a buffer */ + jack_midi_data_t *buffer; /**< Raw MIDI data */ +} jack_midi_event_t; + + +/** + * @defgroup MIDIAPI Reading and writing MIDI data + * @{ + */ + +/** Get number of events in a port buffer. + * + * @param port_buffer Port buffer from which to retrieve event. + * @return number of events inside @a port_buffer + */ +uint32_t +jack_midi_get_event_count(void* port_buffer) JACK_OPTIONAL_WEAK_EXPORT; + + +/** Get a MIDI event from an event port buffer. + * + * Jack MIDI is normalised, the MIDI event returned by this function is + * guaranteed to be a complete MIDI event (the status byte will always be + * present, and no realtime events will interspersed with the event). + * + * This rule does not apply to System Exclusive MIDI messages + * since they can be of arbitrary length. + * To maintain smooth realtime operation such events CAN be delivered + * as multiple, non-normalised events. + * The maximum size of one event "chunk" depends on the MIDI backend in use. + * For example the midiseq driver will create chunks of 256 bytes. + * The first SysEx "chunked" event starts with 0xF0 and the last + * delivered chunk ends with 0xF7. + * To receive the full SysEx message, a caller of jack_midi_event_get() + * must concatenate chunks until a chunk ends with 0xF7. + * + * @param event Event structure to store retrieved event in. + * @param port_buffer Port buffer from which to retrieve event. + * @param event_index Index of event to retrieve. + * @return 0 on success, ENODATA if buffer is empty. + */ +int +jack_midi_event_get(jack_midi_event_t *event, + void *port_buffer, + uint32_t event_index) JACK_OPTIONAL_WEAK_EXPORT; + + +/** Clear an event buffer. + * + * This should be called at the beginning of each process cycle before calling + * @ref jack_midi_event_reserve or @ref jack_midi_event_write. This + * function may not be called on an input port's buffer. + * + * @param port_buffer Port buffer to clear (must be an output port buffer). + */ +void +jack_midi_clear_buffer(void *port_buffer) JACK_OPTIONAL_WEAK_EXPORT; + +/** Reset an event buffer (from data allocated outside of JACK). + * + * This should be called at the beginning of each process cycle before calling + * @ref jack_midi_event_reserve or @ref jack_midi_event_write. This + * function may not be called on an input port's buffer. + * + * @deprecated Please use jack_midi_clear_buffer(). + * + * @param port_buffer Port buffer to reset. + */ +void +jack_midi_reset_buffer(void *port_buffer) JACK_OPTIONAL_WEAK_DEPRECATED_EXPORT; + + +/** Get the size of the largest event that can be stored by the port. + * + * This function returns the current space available, taking into account + * events already stored in the port. + * + * @param port_buffer Port buffer to check size of. + */ +size_t +jack_midi_max_event_size(void* port_buffer) JACK_OPTIONAL_WEAK_EXPORT; + + +/** Allocate space for an event to be written to an event port buffer. + * + * Clients are to write the actual event data to be written starting at the + * pointer returned by this function. Clients must not write more than + * @a data_size bytes into this buffer. Clients must write normalised + * MIDI data to the port - no running status and no (1-byte) realtime + * messages interspersed with other messages (realtime messages are fine + * when they occur on their own, like other messages). + * + * Events must be written in order, sorted by their sample offsets. + * JACK will not sort the events for you, and will refuse to store + * out-of-order events. + * + * @param port_buffer Buffer to write event to. + * @param time Sample offset of event. + * @param data_size Length of event's raw data in bytes. + * @return Pointer to the beginning of the reserved event's data buffer, or + * NULL on error (ie not enough space). + */ +jack_midi_data_t* +jack_midi_event_reserve(void *port_buffer, + jack_nframes_t time, + size_t data_size) JACK_OPTIONAL_WEAK_EXPORT; + + +/** Write an event into an event port buffer. + * + * This function is simply a wrapper for @ref jack_midi_event_reserve + * which writes the event data into the space reserved in the buffer. + * + * Clients must not write more than + * @a data_size bytes into this buffer. Clients must write normalised + * MIDI data to the port - no running status and no (1-byte) realtime + * messages interspersed with other messages (realtime messages are fine + * when they occur on their own, like other messages). + * + * Events must be written in order, sorted by their sample offsets. + * JACK will not sort the events for you, and will refuse to store + * out-of-order events. + * + * @param port_buffer Buffer to write event to. + * @param time Sample offset of event. + * @param data Message data to be written. + * @param data_size Length of @a data in bytes. + * @return 0 on success, ENOBUFS if there's not enough space in buffer for event. + */ +int +jack_midi_event_write(void *port_buffer, + jack_nframes_t time, + const jack_midi_data_t *data, + size_t data_size) JACK_OPTIONAL_WEAK_EXPORT; + + +/** Get the number of events that could not be written to @a port_buffer. + * + * This function returning a non-zero value implies @a port_buffer is full. + * Currently the only way this can happen is if events are lost on port mixdown. + * + * @param port_buffer Port to receive count for. + * @returns Number of events that could not be written to @a port_buffer. + */ +uint32_t +jack_midi_get_lost_event_count(void *port_buffer) JACK_OPTIONAL_WEAK_EXPORT; + +/*@}*/ + +#ifdef __cplusplus +} +#endif + + +#endif /* __JACK_MIDIPORT_H */ + + |