gst-plugins-rs/generic/threadshare/src/runtime/pad.rs
2021-04-12 15:57:19 +02:00

1070 lines
40 KiB
Rust

// Copyright (C) 2019-2020 François Laignel <fengalin@free.fr>
// Copyright (C) 2020 Sebastian Dröge <sebastian@centricular.com>
//
// This library is free software; you can redistribute it and/or
// modify it under the terms of the GNU Library General Public
// License as published by the Free Software Foundation; either
// version 2 of the License, or (at your option) any later version.
//
// This library 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
// Library General Public License for more details.
//
// You should have received a copy of the GNU Library General Public
// License along with this library; if not, write to the
// Free Software Foundation, Inc., 51 Franklin Street, Suite 500,
// Boston, MA 02110-1335, USA.
//! An implementation of `Pad`s to run asynchronous processings.
//!
//! [`PadSink`] & [`PadSrc`] provide an asynchronous API to ease the development of `Element`s in
//! the `threadshare` GStreamer plugins framework.
//!
//! The diagram below shows how the [`PadSrc`] & [`PadSink`] and the related `struct`s integrate in
//! `ts` `Element`s.
//!
//! Note: [`PadSrc`] & [`PadSink`] only support `gst::PadMode::Push` at the moment.
//!
//! ```text
//! ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━┓ ┏━━━━━━━━━━━━━━━━━━━━━━━━━━━━
//! Element A ┃ ┃ Element B
//! ┃ ┃
//! ╭─────────────────╮ ┃ ┃ ╭──────────────────╮
//! │ PadSrc │ ┃ ┃ │ PadSink │
//! │ Handler │ ┃ ┃ │ Handler │
//! │─────────────────│ ┃ ┃ │──────────────────│
//! │ - src_activate* │ ╭──┸──╮ ╭──┸──╮ │ - sink_activate* │
//! │ - src_event* │<────│ │<╌╌╌│ │───>│ - sink_chain* │
//! │ - src_query │<────│ gst │ │ gst │───>│ - sink_event* │
//! │─────────────────│ │ │ │ │───>│ - sink_query │
//! │ - task fn │ │ Pad │ │ Pad │ ╰──────────────────╯
//! ╰─────────────────╯ ╭─>│ │╌╌╌>│ │─╮ │
//! ╭───────╯ │ │ ╰──┰──╯ ╰──┰──╯ ╰───────╮ │
//! ╭────────────╮ ╭────────╮ push* │ ┃ ┃ ╭─────────╮
//! │ Pad Task ↺ │──>│ PadSrc │───────╯ ┃ ┃ │ PadSink │
//! ╰────────────╯ ╰────────╯ ┃ ┃ ╰─────────╯
//! ━━━━━━━│━━━━━━━━━━━━━━│━━━━━━━━━━━━━━━━━┛ ┗━━━━━━━━━━━━━━━│━━━━━━━━━━━━
//! ╰──────────────┴───────────────────╮ ╭─────────────────╯
//! ╭────────────╮
//! │ Context ↺ │
//! ╰────────────╯
//! ```
//!
//! Asynchronous operations for both [`PadSrc`] in `Element A` and [`PadSink`] in `Element B` run on
//! the same [`Context`], which can also be shared by other `Element`s or instances of the same
//! `Element`s in multiple `Pipeline`s.
//!
//! `Element A` & `Element B` can also be linked to non-threadshare `Element`s in which case, they
//! operate in a regular synchronous way.
//!
//! Note that only operations on the streaming thread (serialized events, buffers, serialized
//! queries) are handled from the `PadContext` and asynchronously, everything else operates
//! blocking.
//!
//! [`PadSink`]: struct.PadSink.html
//! [`PadSrc`]: struct.PadSrc.html
//! [`Context`]: ../executor/struct.Context.html
use futures::future;
use futures::future::BoxFuture;
use futures::prelude::*;
use gst::prelude::*;
use gst::subclass::prelude::*;
use gst::{gst_debug, gst_error, gst_fixme, gst_log};
use gst::{FlowError, FlowSuccess};
use std::marker::PhantomData;
use std::ops::Deref;
use std::sync::{Arc, Weak};
use super::executor::{block_on_or_add_sub_task, Context};
use super::RUNTIME_CAT;
#[inline]
fn event_ret_to_event_full_res(
ret: bool,
event_type: gst::EventType,
) -> Result<FlowSuccess, FlowError> {
if ret {
Ok(FlowSuccess::Ok)
} else if event_type == gst::EventType::Caps {
Err(FlowError::NotNegotiated)
} else {
Err(FlowError::Error)
}
}
#[inline]
fn event_to_event_full(ret: bool, event_type: gst::EventType) -> Result<FlowSuccess, FlowError> {
event_ret_to_event_full_res(ret, event_type)
}
#[inline]
fn event_to_event_full_serialized(
ret: BoxFuture<'static, bool>,
event_type: gst::EventType,
) -> BoxFuture<'static, Result<FlowSuccess, FlowError>> {
ret.map(move |ret| event_ret_to_event_full_res(ret, event_type))
.boxed()
}
/// A trait to define `handler`s for [`PadSrc`] callbacks.
///
/// *See the [`pad` module] documentation for a description of the model.*
///
/// [`PadSrc`]: struct.PadSrc.html
/// [`pad` module]: index.html
pub trait PadSrcHandler: Clone + Send + Sync + 'static {
type ElementImpl: ElementImpl + ObjectSubclass;
fn src_activate(
&self,
pad: &PadSrcRef,
_imp: &Self::ElementImpl,
_element: &gst::Element,
) -> Result<(), gst::LoggableError> {
let gst_pad = pad.gst_pad();
if gst_pad.is_active() {
gst_debug!(
RUNTIME_CAT,
obj: gst_pad,
"Already activated in {:?} mode ",
gst_pad.mode()
);
return Ok(());
}
gst_pad
.activate_mode(gst::PadMode::Push, true)
.map_err(|err| {
gst_error!(
RUNTIME_CAT,
obj: gst_pad,
"Error in PadSrc activate: {:?}",
err
);
gst::loggable_error!(RUNTIME_CAT, "Error in PadSrc activate: {:?}", err)
})
}
fn src_activatemode(
&self,
_pad: &PadSrcRef,
_imp: &Self::ElementImpl,
_element: &gst::Element,
_mode: gst::PadMode,
_active: bool,
) -> Result<(), gst::LoggableError> {
Ok(())
}
fn src_event(
&self,
pad: &PadSrcRef,
_imp: &Self::ElementImpl,
element: &gst::Element,
event: gst::Event,
) -> bool {
gst_log!(RUNTIME_CAT, obj: pad.gst_pad(), "Handling {:?}", event);
pad.gst_pad().event_default(Some(element), event)
}
fn src_event_full(
&self,
pad: &PadSrcRef,
imp: &Self::ElementImpl,
element: &gst::Element,
event: gst::Event,
) -> Result<FlowSuccess, FlowError> {
// default is to dispatch to `src_event`
// (as implemented in `gst_pad_send_event_unchecked`)
let event_type = event.type_();
event_to_event_full(self.src_event(pad, imp, element, event), event_type)
}
fn src_query(
&self,
pad: &PadSrcRef,
_imp: &Self::ElementImpl,
element: &gst::Element,
query: &mut gst::QueryRef,
) -> bool {
gst_log!(RUNTIME_CAT, obj: pad.gst_pad(), "Handling {:?}", query);
if query.is_serialized() {
// FIXME serialized queries should be handled with the dataflow
// but we can't return a `Future` because we couldn't honor QueryRef's lifetime
false
} else {
pad.gst_pad().query_default(Some(element), query)
}
}
}
#[derive(Debug)]
pub struct PadSrcInner {
gst_pad: gst::Pad,
}
impl PadSrcInner {
fn new(gst_pad: gst::Pad) -> Self {
if gst_pad.direction() != gst::PadDirection::Src {
panic!("Wrong pad direction for PadSrc");
}
PadSrcInner { gst_pad }
}
pub fn gst_pad(&self) -> &gst::Pad {
&self.gst_pad
}
pub async fn push(&self, buffer: gst::Buffer) -> Result<FlowSuccess, FlowError> {
gst_log!(RUNTIME_CAT, obj: self.gst_pad(), "Pushing {:?}", buffer);
let success = self.gst_pad.push(buffer).map_err(|err| {
gst_error!(RUNTIME_CAT,
obj: self.gst_pad(),
"Failed to push Buffer to PadSrc: {:?}",
err,
);
err
})?;
gst_log!(RUNTIME_CAT, obj: &self.gst_pad, "Processing any pending sub tasks");
while Context::current_has_sub_tasks() {
Context::drain_sub_tasks().await?;
}
Ok(success)
}
pub async fn push_list(&self, list: gst::BufferList) -> Result<FlowSuccess, FlowError> {
gst_log!(RUNTIME_CAT, obj: self.gst_pad(), "Pushing {:?}", list);
let success = self.gst_pad.push_list(list).map_err(|err| {
gst_error!(
RUNTIME_CAT,
obj: self.gst_pad(),
"Failed to push BufferList to PadSrc: {:?}",
err,
);
err
})?;
gst_log!(RUNTIME_CAT, obj: &self.gst_pad, "Processing any pending sub tasks");
while Context::current_has_sub_tasks() {
Context::drain_sub_tasks().await?;
}
Ok(success)
}
pub async fn push_event(&self, event: gst::Event) -> bool {
gst_log!(RUNTIME_CAT, obj: &self.gst_pad, "Pushing {:?}", event);
let was_handled = self.gst_pad().push_event(event);
gst_log!(RUNTIME_CAT, obj: &self.gst_pad, "Processing any pending sub tasks");
while Context::current_has_sub_tasks() {
if Context::drain_sub_tasks().await.is_err() {
return false;
}
}
was_handled
}
}
/// A [`PadSrc`] which can be moved in [`handler`]s functions and `Future`s.
///
/// Call [`upgrade`] to use the [`PadSrc`].
///
/// *See the [`pad` module] documentation for a description of the model.*
///
/// [`PadSrc`]: struct.PadSrc.html
/// [`handler`]: trait.PadSrcHandler.html
/// [`upgrade`]: struct.PadSrcWeak.html#method.upgrade
/// [`pad` module]: index.html
#[derive(Clone, Debug)]
pub struct PadSrcWeak(Weak<PadSrcInner>);
impl PadSrcWeak {
pub fn upgrade(&self) -> Option<PadSrcRef<'_>> {
self.0.upgrade().map(PadSrcRef::new)
}
}
/// A [`PadSrc`] to be used in `Handler`s functions and `Future`s.
///
/// Call [`downgrade`] if you need to `clone` the [`PadSrc`].
///
/// *See the [`pad` module] documentation for a description of the model.*
///
/// [`PadSrc`]: struct.PadSrc.html
/// [`PadSrcWeak`]: struct.PadSrcWeak.html
/// [`downgrade`]: struct.PadSrcRef.html#method.downgrade
/// [`pad` module]: index.html
#[derive(Debug)]
pub struct PadSrcRef<'a> {
strong: Arc<PadSrcInner>,
phantom: PhantomData<&'a Self>,
}
impl<'a> PadSrcRef<'a> {
fn new(inner_arc: Arc<PadSrcInner>) -> Self {
PadSrcRef {
strong: inner_arc,
phantom: PhantomData,
}
}
pub fn downgrade(&self) -> PadSrcWeak {
PadSrcWeak(Arc::downgrade(&self.strong))
}
fn activate_mode_hook(
&self,
mode: gst::PadMode,
active: bool,
) -> Result<(), gst::LoggableError> {
// Important: don't panic here as the hook is used without `catch_panic_pad_function`
// in the default `activatemode` handling
gst_log!(RUNTIME_CAT, obj: self.gst_pad(), "ActivateMode {:?}, {}", mode, active);
if mode == gst::PadMode::Pull {
gst_error!(RUNTIME_CAT, obj: self.gst_pad(), "Pull mode not supported by PadSrc");
return Err(gst::loggable_error!(
RUNTIME_CAT,
"Pull mode not supported by PadSrc"
));
}
Ok(())
}
}
impl<'a> Deref for PadSrcRef<'a> {
type Target = PadSrcInner;
fn deref(&self) -> &Self::Target {
&self.strong
}
}
/// The `PadSrc` which `Element`s must own.
///
/// Call [`downgrade`] if you need to `clone` the `PadSrc`.
///
/// *See the [`pad` module] documentation for a description of the model.*
///
/// [`downgrade`]: struct.PadSrc.html#method.downgrade
/// [`pad` module]: index.html
#[derive(Debug)]
pub struct PadSrc(Arc<PadSrcInner>);
impl PadSrc {
pub fn new(gst_pad: gst::Pad, handler: impl PadSrcHandler) -> Self {
let this = PadSrc(Arc::new(PadSrcInner::new(gst_pad)));
this.init_pad_functions(handler);
this
}
pub fn downgrade(&self) -> PadSrcWeak {
PadSrcWeak(Arc::downgrade(&self.0))
}
pub fn as_ref(&self) -> PadSrcRef<'_> {
PadSrcRef::new(Arc::clone(&self.0))
}
pub fn check_reconfigure(&self) -> bool {
self.0.gst_pad().check_reconfigure()
}
fn init_pad_functions<H: PadSrcHandler>(&self, handler: H) {
// FIXME: Do this better
unsafe {
let handler_clone = handler.clone();
let inner_arc = Arc::clone(&self.0);
self.0
.gst_pad()
.set_activate_function(move |gst_pad, parent| {
let handler = handler_clone.clone();
let inner_arc = inner_arc.clone();
H::ElementImpl::catch_panic_pad_function(
parent,
|| {
gst_error!(RUNTIME_CAT, obj: gst_pad, "Panic in PadSrc activate");
Err(gst::loggable_error!(
RUNTIME_CAT,
"Panic in PadSrc activate"
))
},
move |imp, element| {
let this_ref = PadSrcRef::new(inner_arc);
handler.src_activate(
&this_ref,
imp,
element.dynamic_cast_ref::<gst::Element>().unwrap(),
)
},
)
});
let handler_clone = handler.clone();
let inner_arc = Arc::clone(&self.0);
self.gst_pad()
.set_activatemode_function(move |gst_pad, parent, mode, active| {
let handler = handler_clone.clone();
let inner_arc = inner_arc.clone();
H::ElementImpl::catch_panic_pad_function(
parent,
|| {
gst_error!(RUNTIME_CAT, obj: gst_pad, "Panic in PadSrc activatemode");
Err(gst::loggable_error!(
RUNTIME_CAT,
"Panic in PadSrc activatemode"
))
},
move |imp, element| {
let this_ref = PadSrcRef::new(inner_arc);
this_ref.activate_mode_hook(mode, active)?;
handler.src_activatemode(
&this_ref,
imp,
element.dynamic_cast_ref::<gst::Element>().unwrap(),
mode,
active,
)
},
)
});
// No need to `set_event_function` since `set_event_full_function`
// overrides it and dispatches to `src_event` when necessary
let handler_clone = handler.clone();
let inner_arc = Arc::clone(&self.0);
self.gst_pad()
.set_event_full_function(move |_gst_pad, parent, event| {
let handler = handler_clone.clone();
let inner_arc = inner_arc.clone();
H::ElementImpl::catch_panic_pad_function(
parent,
|| Err(FlowError::Error),
move |imp, element| {
let this_ref = PadSrcRef::new(inner_arc);
handler.src_event_full(
&this_ref,
imp,
element.dynamic_cast_ref::<gst::Element>().unwrap(),
event,
)
},
)
});
let inner_arc = Arc::clone(&self.0);
self.gst_pad()
.set_query_function(move |_gst_pad, parent, query| {
let handler = handler.clone();
let inner_arc = inner_arc.clone();
H::ElementImpl::catch_panic_pad_function(
parent,
|| false,
move |imp, element| {
let this_ref = PadSrcRef::new(inner_arc);
if !query.is_serialized() {
handler.src_query(&this_ref, imp, element.dynamic_cast_ref::<gst::Element>().unwrap(), query)
} else {
gst_fixme!(RUNTIME_CAT, obj: this_ref.gst_pad(), "Serialized Query not supported");
false
}
},
)
});
}
}
}
impl Drop for PadSrc {
fn drop(&mut self) {
// FIXME: Do this better
unsafe {
self.gst_pad()
.set_activate_function(move |_gst_pad, _parent| {
Err(gst::loggable_error!(RUNTIME_CAT, "PadSrc no longer exists"))
});
self.gst_pad()
.set_activatemode_function(move |_gst_pad, _parent, _mode, _active| {
Err(gst::loggable_error!(RUNTIME_CAT, "PadSrc no longer exists"))
});
self.gst_pad()
.set_event_function(move |_gst_pad, _parent, _event| false);
self.gst_pad()
.set_event_full_function(move |_gst_pad, _parent, _event| Err(FlowError::Flushing));
self.gst_pad()
.set_query_function(move |_gst_pad, _parent, _query| false);
}
}
}
impl Deref for PadSrc {
type Target = PadSrcInner;
fn deref(&self) -> &Self::Target {
&self.0
}
}
/// A trait to define `handler`s for [`PadSink`] callbacks.
///
/// *See the [`pad` module] documentation for a description of the model.*
///
/// [`PadSink`]: struct.PadSink.html
/// [`pad` module]: index.html
pub trait PadSinkHandler: Clone + Send + Sync + 'static {
type ElementImpl: ElementImpl + ObjectSubclass;
// FIXME: Once associated type bounds are stable we should use ObjectSubclass::Type below
// instead of &gst::Element
fn sink_activate(
&self,
pad: &PadSinkRef,
_imp: &Self::ElementImpl,
_element: &gst::Element,
) -> Result<(), gst::LoggableError> {
let gst_pad = pad.gst_pad();
if gst_pad.is_active() {
gst_debug!(
RUNTIME_CAT,
obj: gst_pad,
"Already activated in {:?} mode ",
gst_pad.mode()
);
return Ok(());
}
gst_pad
.activate_mode(gst::PadMode::Push, true)
.map_err(|err| {
gst_error!(
RUNTIME_CAT,
obj: gst_pad,
"Error in PadSink activate: {:?}",
err
);
gst::loggable_error!(RUNTIME_CAT, "Error in PadSink activate: {:?}", err)
})
}
fn sink_activatemode(
&self,
_pad: &PadSinkRef,
_imp: &Self::ElementImpl,
_element: &gst::Element,
_mode: gst::PadMode,
_active: bool,
) -> Result<(), gst::LoggableError> {
Ok(())
}
fn sink_chain(
&self,
_pad: &PadSinkRef,
_imp: &Self::ElementImpl,
_element: &gst::Element,
_buffer: gst::Buffer,
) -> BoxFuture<'static, Result<FlowSuccess, FlowError>> {
future::err(FlowError::NotSupported).boxed()
}
fn sink_chain_list(
&self,
_pad: &PadSinkRef,
_imp: &Self::ElementImpl,
_element: &gst::Element,
_buffer_list: gst::BufferList,
) -> BoxFuture<'static, Result<FlowSuccess, FlowError>> {
future::err(FlowError::NotSupported).boxed()
}
fn sink_event(
&self,
pad: &PadSinkRef,
_imp: &Self::ElementImpl,
element: &gst::Element,
event: gst::Event,
) -> bool {
assert!(!event.is_serialized());
gst_log!(RUNTIME_CAT, obj: pad.gst_pad(), "Handling {:?}", event);
pad.gst_pad().event_default(Some(element), event)
}
fn sink_event_serialized(
&self,
pad: &PadSinkRef,
_imp: &Self::ElementImpl,
element: &gst::Element,
event: gst::Event,
) -> BoxFuture<'static, bool> {
assert!(event.is_serialized());
let pad_weak = pad.downgrade();
let element = element.clone();
async move {
let pad = pad_weak.upgrade().expect("PadSink no longer exists");
gst_log!(RUNTIME_CAT, obj: pad.gst_pad(), "Handling {:?}", event);
pad.gst_pad().event_default(Some(&element), event)
}
.boxed()
}
fn sink_event_full(
&self,
pad: &PadSinkRef,
imp: &Self::ElementImpl,
element: &gst::Element,
event: gst::Event,
) -> Result<FlowSuccess, FlowError> {
assert!(!event.is_serialized());
// default is to dispatch to `sink_event`
// (as implemented in `gst_pad_send_event_unchecked`)
let event_type = event.type_();
event_to_event_full(self.sink_event(pad, imp, element, event), event_type)
}
fn sink_event_full_serialized(
&self,
pad: &PadSinkRef,
imp: &Self::ElementImpl,
element: &gst::Element,
event: gst::Event,
) -> BoxFuture<'static, Result<FlowSuccess, FlowError>> {
assert!(event.is_serialized());
// default is to dispatch to `sink_event`
// (as implemented in `gst_pad_send_event_unchecked`)
let event_type = event.type_();
event_to_event_full_serialized(
self.sink_event_serialized(pad, imp, element, event),
event_type,
)
}
fn sink_query(
&self,
pad: &PadSinkRef,
_imp: &Self::ElementImpl,
element: &gst::Element,
query: &mut gst::QueryRef,
) -> bool {
if query.is_serialized() {
gst_log!(RUNTIME_CAT, obj: pad.gst_pad(), "Dropping {:?}", query);
// FIXME serialized queries should be handled with the dataflow
// but we can't return a `Future` because we couldn't honor QueryRef's lifetime
false
} else {
gst_log!(RUNTIME_CAT, obj: pad.gst_pad(), "Handling {:?}", query);
pad.gst_pad().query_default(Some(element), query)
}
}
}
#[derive(Debug)]
pub struct PadSinkInner {
gst_pad: gst::Pad,
}
impl PadSinkInner {
fn new(gst_pad: gst::Pad) -> Self {
if gst_pad.direction() != gst::PadDirection::Sink {
panic!("Wrong pad direction for PadSink");
}
PadSinkInner { gst_pad }
}
pub fn gst_pad(&self) -> &gst::Pad {
&self.gst_pad
}
}
/// A [`PadSink`] which can be moved in `Handler`s functions and `Future`s.
///
/// Call [`upgrade`] to use the [`PadSink`].
///
/// *See the [`pad` module] documentation for a description of the model.*
///
/// [`PadSink`]: struct.PadSink.html
/// [`upgrade`]: struct.PadSinkWeak.html#method.upgrade
/// [`pad` module]: index.html
#[derive(Clone, Debug)]
pub struct PadSinkWeak(Weak<PadSinkInner>);
impl PadSinkWeak {
pub fn upgrade(&self) -> Option<PadSinkRef<'_>> {
self.0.upgrade().map(PadSinkRef::new)
}
}
/// A [`PadSink`] to be used in [`handler`]s functions and `Future`s.
///
/// Call [`downgrade`] if you need to `clone` the [`PadSink`].
///
/// *See the [`pad` module] documentation for a description of the model.*
///
/// [`PadSink`]: struct.PadSink.html
/// [`handler`]: trait.PadSinkHandler.html
/// [`downgrade`]: struct.PadSinkRef.html#method.downgrade
/// [`pad` module]: index.html
#[derive(Debug)]
pub struct PadSinkRef<'a> {
strong: Arc<PadSinkInner>,
phantom: PhantomData<&'a Self>,
}
impl<'a> PadSinkRef<'a> {
fn new(inner_arc: Arc<PadSinkInner>) -> Self {
PadSinkRef {
strong: inner_arc,
phantom: PhantomData,
}
}
pub fn downgrade(&self) -> PadSinkWeak {
PadSinkWeak(Arc::downgrade(&self.strong))
}
fn activate_mode_hook(
&self,
mode: gst::PadMode,
active: bool,
) -> Result<(), gst::LoggableError> {
// Important: don't panic here as the hook is used without `catch_panic_pad_function`
// in the default `activatemode` handling
gst_log!(RUNTIME_CAT, obj: self.gst_pad(), "ActivateMode {:?}, {}", mode, active);
if mode == gst::PadMode::Pull {
gst_error!(RUNTIME_CAT, obj: self.gst_pad(), "Pull mode not supported by PadSink");
return Err(gst::loggable_error!(
RUNTIME_CAT,
"Pull mode not supported by PadSink"
));
}
Ok(())
}
fn handle_future(
&self,
fut: impl Future<Output = Result<FlowSuccess, FlowError>> + Send + 'static,
) -> Result<FlowSuccess, FlowError> {
if let Err(fut) = Context::add_sub_task(fut.map(|res| res.map(drop))) {
block_on_or_add_sub_task(fut.map(|res| res.map(|_| gst::FlowSuccess::Ok)))
.unwrap_or(Ok(gst::FlowSuccess::Ok))
} else {
Ok(gst::FlowSuccess::Ok)
}
}
}
impl<'a> Deref for PadSinkRef<'a> {
type Target = PadSinkInner;
fn deref(&self) -> &Self::Target {
&self.strong
}
}
/// The `PadSink` which `Element`s must own.
///
/// Call [`downgrade`] if you need to `clone` the `PadSink`.
///
/// *See the [`pad` module] documentation for a description of the model.*
///
/// [`downgrade`]: struct.PadSink.html#method.downgrade
/// [`pad` module]: index.html
#[derive(Debug)]
pub struct PadSink(Arc<PadSinkInner>);
impl PadSink {
pub fn new(gst_pad: gst::Pad, handler: impl PadSinkHandler) -> Self {
let this = PadSink(Arc::new(PadSinkInner::new(gst_pad)));
this.init_pad_functions(handler);
this
}
pub fn downgrade(&self) -> PadSinkWeak {
PadSinkWeak(Arc::downgrade(&self.0))
}
pub fn as_ref(&self) -> PadSinkRef<'_> {
PadSinkRef::new(Arc::clone(&self.0))
}
fn init_pad_functions<H: PadSinkHandler>(&self, handler: H) {
// FIXME: Do this better
unsafe {
let handler_clone = handler.clone();
let inner_arc = Arc::clone(&self.0);
self.gst_pad()
.set_activate_function(move |gst_pad, parent| {
let handler = handler_clone.clone();
let inner_arc = inner_arc.clone();
H::ElementImpl::catch_panic_pad_function(
parent,
|| {
gst_error!(RUNTIME_CAT, obj: gst_pad, "Panic in PadSink activate");
Err(gst::loggable_error!(
RUNTIME_CAT,
"Panic in PadSink activate"
))
},
move |imp, element| {
let this_ref = PadSinkRef::new(inner_arc);
handler.sink_activate(
&this_ref,
imp,
element.dynamic_cast_ref::<gst::Element>().unwrap(),
)
},
)
});
let handler_clone = handler.clone();
let inner_arc = Arc::clone(&self.0);
self.gst_pad()
.set_activatemode_function(move |gst_pad, parent, mode, active| {
let handler = handler_clone.clone();
let inner_arc = inner_arc.clone();
H::ElementImpl::catch_panic_pad_function(
parent,
|| {
gst_error!(RUNTIME_CAT, obj: gst_pad, "Panic in PadSink activatemode");
Err(gst::loggable_error!(
RUNTIME_CAT,
"Panic in PadSink activatemode"
))
},
move |imp, element| {
let this_ref = PadSinkRef::new(inner_arc);
this_ref.activate_mode_hook(mode, active)?;
handler.sink_activatemode(
&this_ref,
imp,
element.dynamic_cast_ref::<gst::Element>().unwrap(),
mode,
active,
)
},
)
});
let handler_clone = handler.clone();
let inner_arc = Arc::clone(&self.0);
self.gst_pad()
.set_chain_function(move |_gst_pad, parent, buffer| {
let handler = handler_clone.clone();
let inner_arc = inner_arc.clone();
H::ElementImpl::catch_panic_pad_function(
parent,
|| Err(FlowError::Error),
move |imp, element| {
if Context::current_has_sub_tasks() {
let this_weak = PadSinkWeak(Arc::downgrade(&inner_arc));
let handler = handler.clone();
let element =
element.clone().dynamic_cast::<gst::Element>().unwrap();
let delayed_fut = async move {
let imp = <H::ElementImpl as ObjectSubclassExt>::from_instance(
element.unsafe_cast_ref(),
);
let this_ref =
this_weak.upgrade().ok_or(gst::FlowError::Flushing)?;
handler.sink_chain(&this_ref, imp, &element, buffer).await
};
let _ = Context::add_sub_task(delayed_fut.map(|res| res.map(drop)));
Ok(gst::FlowSuccess::Ok)
} else {
let this_ref = PadSinkRef::new(inner_arc);
let chain_fut = handler.sink_chain(
&this_ref,
imp,
element.dynamic_cast_ref::<gst::Element>().unwrap(),
buffer,
);
this_ref.handle_future(chain_fut)
}
},
)
});
let handler_clone = handler.clone();
let inner_arc = Arc::clone(&self.0);
self.gst_pad()
.set_chain_list_function(move |_gst_pad, parent, list| {
let handler = handler_clone.clone();
let inner_arc = inner_arc.clone();
H::ElementImpl::catch_panic_pad_function(
parent,
|| Err(FlowError::Error),
move |imp, element| {
if Context::current_has_sub_tasks() {
let this_weak = PadSinkWeak(Arc::downgrade(&inner_arc));
let handler = handler.clone();
let element =
element.clone().dynamic_cast::<gst::Element>().unwrap();
let delayed_fut = async move {
let imp = <H::ElementImpl as ObjectSubclassExt>::from_instance(
element.unsafe_cast_ref(),
);
let this_ref =
this_weak.upgrade().ok_or(gst::FlowError::Flushing)?;
handler
.sink_chain_list(&this_ref, imp, &element, list)
.await
};
let _ = Context::add_sub_task(delayed_fut.map(|res| res.map(drop)));
Ok(gst::FlowSuccess::Ok)
} else {
let this_ref = PadSinkRef::new(inner_arc);
let chain_list_fut = handler.sink_chain_list(
&this_ref,
imp,
element.dynamic_cast_ref::<gst::Element>().unwrap(),
list,
);
this_ref.handle_future(chain_list_fut)
}
},
)
});
// No need to `set_event_function` since `set_event_full_function`
// overrides it and dispatches to `sink_event` when necessary
let handler_clone = handler.clone();
let inner_arc = Arc::clone(&self.0);
self.gst_pad()
.set_event_full_function(move |_gst_pad, parent, event| {
let handler = handler_clone.clone();
let inner_arc = inner_arc.clone();
H::ElementImpl::catch_panic_pad_function(
parent,
|| Err(FlowError::Error),
move |imp, element| {
if event.is_serialized() {
if Context::current_has_sub_tasks() {
let this_weak = PadSinkWeak(Arc::downgrade(&inner_arc));
let handler = handler.clone();
let element =
element.clone().dynamic_cast::<gst::Element>().unwrap();
let delayed_fut = async move {
let imp =
<H::ElementImpl as ObjectSubclassExt>::from_instance(
element.unsafe_cast_ref(),
);
let this_ref =
this_weak.upgrade().ok_or(gst::FlowError::Flushing)?;
handler
.sink_event_full_serialized(
&this_ref, imp, &element, event,
)
.await
};
let _ =
Context::add_sub_task(delayed_fut.map(|res| res.map(drop)));
Ok(gst::FlowSuccess::Ok)
} else {
let this_ref = PadSinkRef::new(inner_arc);
let event_fut = handler.sink_event_full_serialized(
&this_ref,
imp,
element.dynamic_cast_ref::<gst::Element>().unwrap(),
event,
);
this_ref.handle_future(event_fut)
}
} else {
let this_ref = PadSinkRef::new(inner_arc);
handler.sink_event_full(
&this_ref,
imp,
element.dynamic_cast_ref::<gst::Element>().unwrap(),
event,
)
}
},
)
});
let inner_arc = Arc::clone(&self.0);
self.gst_pad()
.set_query_function(move |_gst_pad, parent, query| {
let handler = handler.clone();
let inner_arc = inner_arc.clone();
H::ElementImpl::catch_panic_pad_function(
parent,
|| false,
move |imp, element| {
let this_ref = PadSinkRef::new(inner_arc);
if !query.is_serialized() {
handler.sink_query(&this_ref, imp, element.dynamic_cast_ref::<gst::Element>().unwrap(), query)
} else {
gst_fixme!(RUNTIME_CAT, obj: this_ref.gst_pad(), "Serialized Query not supported");
false
}
},
)
});
}
}
}
impl Drop for PadSink {
fn drop(&mut self) {
// FIXME: Do this better
unsafe {
self.gst_pad()
.set_activate_function(move |_gst_pad, _parent| {
Err(gst::loggable_error!(
RUNTIME_CAT,
"PadSink no longer exists"
))
});
self.gst_pad()
.set_activatemode_function(move |_gst_pad, _parent, _mode, _active| {
Err(gst::loggable_error!(
RUNTIME_CAT,
"PadSink no longer exists"
))
});
self.gst_pad()
.set_chain_function(move |_gst_pad, _parent, _buffer| Err(FlowError::Flushing));
self.gst_pad()
.set_chain_list_function(move |_gst_pad, _parent, _list| Err(FlowError::Flushing));
self.gst_pad()
.set_event_function(move |_gst_pad, _parent, _event| false);
self.gst_pad()
.set_event_full_function(move |_gst_pad, _parent, _event| Err(FlowError::Flushing));
self.gst_pad()
.set_query_function(move |_gst_pad, _parent, _query| false);
}
}
}
impl Deref for PadSink {
type Target = PadSinkInner;
fn deref(&self) -> &Self::Target {
&self.0
}
}