Initial import of lv2plug.in universe.

1 files changed, 259 insertions, 0 deletions

diff --git a/ext/event.lv2/event.h b/ext/event.lv2/event.h
new file mode 100644
index 0000000..7fb189c
--- /dev/null
+++ b/ext/event.lv2/event.h
@@ -0,0 +1,259 @@
+/* lv2_event.h - C header file for the LV2 events extension.
+ *
+ * Copyright (C) 2006-2007 Lars Luthman <lars.luthman@gmail.com>
+ * Copyright (C) 2008-2009 David Robillard <http://drobilla.net>
+ *
+ * This header 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 of the License, or
+ * (at your option) any later version.
+ *
+ * This header 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 header; if not, write to the Free Software Foundation,
+ * Inc., 59 Temple Place, Suite 330, Boston, MA 01222-1307 USA
+ */
+
+#ifndef LV2_EVENT_H
+#define LV2_EVENT_H
+
+#define LV2_EVENT_URI "http://lv2plug.in/ns/ext/event"
+#define LV2_EVENT_AUDIO_STAMP 0
+
+#include <stdint.h>
+
+/** @file
+ * C header for the LV2 Event extension <http://lv2plug.in/ns/ext/event>.
+ *
+ * This extension is a generic transport mechanism for time stamped events
+ * of any type (e.g. MIDI, OSC, ramps, etc).  Each port can transport mixed
+ * events of any type; the type of events and timestamps are defined by a URI
+ * which is mapped to an integer by the host for performance reasons.
+ *
+ * This extension requires the host to support the LV2 URI Map extension.
+ * Any host which supports this extension MUST guarantee that any call to
+ * the LV2 URI Map uri_to_id function with the URI of this extension as the
+ * 'map' argument returns a value within the range of uint16_t.
+ */
+
+
+/** The best Pulses Per Quarter Note for tempo-based uint32_t timestmaps.
+ * Equal to 2^12 * 5 * 7 * 9 * 11 * 13 * 17, which is evenly divisble
+ * by all integers from 1 through 18 inclusive, and powers of 2 up to 2^12.
+ */
+static const uint32_t LV2_EVENT_PPQN = 3136573440U;
+
+
+/** An LV2 event (header only).
+ *
+ * LV2 events are generic time-stamped containers for any type of event.
+ * The type field defines the format of a given event's contents.
+ *
+ * This struct defines the header of an LV2 event.  An LV2 event is a single
+ * chunk of POD (plain old data), usually contained in a flat buffer
+ * (see LV2_EventBuffer below).  Unless a required feature says otherwise,
+ * hosts may assume a deep copy of an LV2 event can be created safely
+ * using a simple:
+ *
+ * memcpy(ev_copy, ev, sizeof(LV2_Event) + ev->size);  (or equivalent)
+ */
+typedef struct {
+
+	/** The frames portion of timestamp.  The units used here can optionally be
+	 * set for a port (with the lv2ev:timeUnits property), otherwise this
+	 * is audio frames, corresponding to the sample_count parameter of the
+	 * LV2 run method (e.g. frame 0 is the first frame for that call to run).
+	 */
+	uint32_t frames;
+
+	/** The sub-frames portion of timestamp.  The units used here can
+	 * optionally be set for a port (with the lv2ev:timeUnits property),
+	 * otherwise this is 1/(2^32) of an audio frame.
+	 */
+	uint32_t subframes;
+
+	/** The type of this event, as a number which represents some URI
+	 * defining an event type.  This value MUST be some value previously
+	 * returned from a call to the uri_to_id function defined in the LV2
+	 * URI map extension (see lv2_uri_map.h).
+	 * There are special rules which must be followed depending on the type
+	 * of an event.  If the plugin recognizes an event type, the definition
+	 * of that event type will describe how to interpret the event, and
+	 * any required behaviour.  Otherwise, if the type is 0, this event is a
+	 * non-POD event and lv2_event_unref MUST be called if the event is
+	 * 'dropped' (see above).  Even if the plugin does not understand an event,
+	 * it may pass the event through to an output by simply copying (and NOT
+	 * calling lv2_event_unref).  These rules are designed to allow for generic
+	 * event handling plugins and large non-POD events, but with minimal hassle
+	 * on simple plugins that "don't care" about these more advanced features.
+	 */
+	uint16_t type;
+
+	/** The size of the data portion of this event in bytes, which immediately
+	 * follows.  The header size (12 bytes) is not included in this value.
+	 */
+	uint16_t size;
+
+	/* size bytes of data follow here */
+
+} LV2_Event;
+
+
+
+/** A buffer of LV2 events (header only).
+ *
+ * Like events (which this contains) an event buffer is a single chunk of POD:
+ * the entire buffer (including contents) can be copied with a single memcpy.
+ * The first contained event begins sizeof(LV2_EventBuffer) bytes after
+ * the start of this struct.
+ *
+ * After this header, the buffer contains an event header (defined by struct
+ * LV2_Event), followed by that event's contents (padded to 64 bits), followed by
+ * another header, etc:
+ *
+ * |       |       |       |       |       |       |
+ * | | | | | | | | | | | | | | | | | | | | | | | | |
+ * |FRAMES |SUBFRMS|TYP|LEN|DATA..DATA..PAD|FRAMES | ...
+ */
+typedef struct {
+
+	/** The contents of the event buffer.  This may or may not reside in the
+	 * same block of memory as this header, plugins must not assume either.
+	 * The host guarantees this points to at least capacity bytes of allocated
+	 * memory (though only size bytes of that are valid events).
+	 */
+	uint8_t* data;
+
+	/** The size of this event header in bytes (including everything).
+	 *
+	 * This is to allow for extending this header in the future without
+	 * breaking binary compatibility.  Whenever this header is copied,
+	 * it MUST be done using this field (and NOT the sizeof this struct).
+	 */
+	uint16_t header_size;
+
+	/** The type of the time stamps for events in this buffer.
+	 * As a special exception, '0' always means audio frames and subframes
+	 * (1/UINT32_MAX'th of a frame) in the sample rate passed to instantiate.
+	 * INPUTS: The host must set this field to the numeric ID of some URI
+	 *     defining the meaning of the frames/subframes fields of contained
+	 *     events (obtained by the LV2 URI Map uri_to_id function with the URI
+	 *     of this extension as the 'map' argument, see lv2_uri_map.h).
+	 *     The host must never pass a plugin a buffer which uses a stamp type
+	 *     the plugin does not 'understand'.  The value of this field must
+	 *     never change, except when connect_port is called on the input
+	 *     port, at which time the host MUST have set the stamp_type field to
+	 *     the value that will be used for all subsequent run calls.
+	 * OUTPUTS: The plugin may set this to any value that has been returned
+	 *     from uri_to_id with the URI of this extension for a 'map' argument.
+	 *     When connected to a buffer with connect_port, output ports MUST set
+	 *     this field to the type of time stamp they will be writing.  On any
+	 *     call to connect_port on an event input port, the plugin may change
+	 *     this field on any output port, it is the responsibility of the host
+	 *     to check if any of these values have changed and act accordingly.
+	 */
+	uint16_t stamp_type;
+
+	/** The number of events in this buffer.
+	 * INPUTS: The host must set this field to the number of events
+	 *     contained in the data buffer before calling run().
+	 *     The plugin must not change this field.
+	 * OUTPUTS: The plugin must set this field to the number of events it
+	 *     has written to the buffer before returning from run().
+	 *     Any initial value should be ignored by the plugin.
+	 */
+	uint32_t event_count;
+
+	/** The size of the data buffer in bytes.
+	 * This is set by the host and must not be changed by the plugin.
+	 * The host is allowed to change this between run() calls.
+	 */
+	uint32_t capacity;
+
+	/** The size of the initial portion of the data buffer containing data.
+	 * INPUTS: The host must set this field to the number of bytes used
+	 *     by all events it has written to the buffer (including headers)
+	 *     before calling the plugin's run().
+	 *     The plugin must not change this field.
+	 * OUTPUTS: The plugin must set this field to the number of bytes
+	 *     used by all events it has written to the buffer (including headers)
+	 *     before returning from run().
+	 *     Any initial value should be ignored by the plugin.
+	 */
+	uint32_t size;
+
+} LV2_Event_Buffer;
+
+
+/** Opaque pointer to host data. */
+typedef void* LV2_Event_Callback_Data;
+
+
+/** The data field of the LV2_Feature for this extension.
+ *
+ * To support this feature the host must pass an LV2_Feature struct to the
+ * plugin's instantiate method with URI "http://lv2plug.in/ns/ext/event"
+ * and data pointed to an instance of this struct.
+ */
+typedef struct {
+
+	/** Opaque pointer to host data.
+	 *
+	 * The plugin MUST pass this to any call to functions in this struct.
+	 * Otherwise, it must not be interpreted in any way.
+	 */
+	LV2_Event_Callback_Data callback_data;
+
+	/** Take a reference to a non-POD event.
+	 *
+	 * If a plugin receives an event with type 0, it means the event is a
+	 * pointer to some object in memory and not a flat sequence of bytes
+	 * in the buffer.  When receiving a non-POD event, the plugin already
+	 * has an implicit reference to the event.  If the event is stored AND
+	 * passed to an output, lv2_event_ref MUST be called on that event.
+	 * If the event is only stored OR passed through, this is not necessary
+	 * (as the plugin already has 1 implicit reference).
+	 *
+	 * @param event An event received at an input that will not be copied to
+	 *              an output or stored in any way.
+	 * @param context The calling context.  (Like event types) this is a mapped
+	 *                URI, see lv2_context.h. Simple plugin with just a run()
+	 *                method should pass 0 here (the ID of the 'standard' LV2
+	 *                run context).  The host guarantees that this function is
+	 *                realtime safe iff @a context is realtime safe.
+	 *
+	 * PLUGINS THAT VIOLATE THESE RULES MAY CAUSE CRASHES AND MEMORY LEAKS.
+	 */
+	uint32_t (*lv2_event_ref)(LV2_Event_Callback_Data callback_data,
+	                          LV2_Event*              event);
+
+	/** Drop a reference to a non-POD event.
+	 *
+	 * If a plugin receives an event with type 0, it means the event is a
+	 * pointer to some object in memory and not a flat sequence of bytes
+	 * in the buffer.  If the plugin does not pass the event through to
+	 * an output or store it internally somehow, it MUST call this function
+	 * on the event (more information on using non-POD events below).
+	 *
+	 * @param event An event received at an input that will not be copied to
+	 *              an output or stored in any way.
+	 * @param context The calling context.  (Like event types) this is a mapped
+	 *                URI, see lv2_context.h. Simple plugin with just a run()
+	 *                method should pass 0 here (the ID of the 'standard' LV2
+	 *                run context).  The host guarantees that this function is
+	 *                realtime safe iff @a context is realtime safe.
+	 *
+	 * PLUGINS THAT VIOLATE THESE RULES MAY CAUSE CRASHES AND MEMORY LEAKS.
+	 */
+	uint32_t (*lv2_event_unref)(LV2_Event_Callback_Data callback_data,
+	                            LV2_Event*              event);
+
+} LV2_Event_Feature;
+
+
+#endif /* LV2_EVENT_H */
+