Struct lv2_sys::LV2_Event_Feature

#[repr(C)]pub struct LV2_Event_Feature {
    pub callback_data: LV2_Event_Callback_Data,
    pub lv2_event_ref: Option<unsafe extern "C" fn(callback_data: LV2_Event_Callback_Data, event: *mut LV2_Event) -> u32>,
    pub lv2_event_unref: Option<unsafe extern "C" fn(callback_data: LV2_Event_Callback_Data, event: *mut LV2_Event) -> u32>,
}

Non-POD events feature.

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. Note this feature is not mandatory to support the event extension.

Fields

callback_data: LV2_Event_Callback_Data

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_ref: Option<unsafe extern "C" fn(callback_data: LV2_Event_Callback_Data, event: *mut LV2_Event) -> u32>

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 the context is realtime safe.

PLUGINS THAT VIOLATE THESE RULES MAY CAUSE CRASHES AND MEMORY LEAKS.

lv2_event_unref: Option<unsafe extern "C" fn(callback_data: LV2_Event_Callback_Data, event: *mut LV2_Event) -> u32>

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 the context is realtime safe.

PLUGINS THAT VIOLATE THESE RULES MAY CAUSE CRASHES AND MEMORY LEAKS.

Trait Implementations

impl Clone for LV2_Event_Feature

fn clone(&self) -> LV2_Event_Feature

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Copy for LV2_Event_Feature

impl Debug for LV2_Event_Feature

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.