hlssink3/hlscmafsink: Make GioOutputStream a sub-class of OutputStream

Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-rs/-/merge_requests/2439>

net/hlssink3/src/hlsbasesink.rs

@@ -10,6 +10,7 @@
 use crate::playlist::Playlist;
 use chrono::{DateTime, Duration, Utc};
 use gio::prelude::*;
+use gio::subclass::prelude::OutputStreamImpl;
 use gst::glib;
 use gst::prelude::*;
 use gst::subclass::prelude::*;
@@ -17,8 +18,7 @@ use m3u8_rs::MediaSegment;
 use std::fs;
 use std::io::Write;
 use std::path;
-use std::sync::LazyLock;
-use std::sync::Mutex;
+use std::sync::{LazyLock, Mutex};
 
 const DEFAULT_PLAYLIST_LOCATION: &str = "playlist.m3u8";
 const DEFAULT_MAX_NUM_SEGMENT_FILES: u32 = 10;
@@ -60,20 +60,70 @@ pub enum HlsProgramDateTimeReference {
 // We need to keep an OutputStream around for writing to the same file
 // to support the single media file use case. OutputStream not being
 // thread safe, use this wrapper to keep an OutputStream around in State.
-struct GioOutputStream {
-    stream: gio::OutputStream,
+#[derive(Default)]
+pub struct HlsBaseSinkGioOutputStream {
+    stream: Mutex<Option<gio::OutputStream>>,
+    out_bytes: Mutex<usize>,
 }
 
-unsafe impl Send for GioOutputStream {}
-unsafe impl Sync for GioOutputStream {}
+unsafe impl Send for HlsBaseSinkGioOutputStream {}
+unsafe impl Sync for HlsBaseSinkGioOutputStream {}
 
-impl GioOutputStream {
-    pub fn new(stream: gio::OutputStream) -> Self {
-        Self { stream }
+#[glib::object_subclass]
+impl ObjectSubclass for HlsBaseSinkGioOutputStream {
+    const NAME: &'static str = "GstHlsBaseSinkGioOutputStream";
+    type Type = super::HlsBaseSinkGioOutputStream;
+    type ParentType = gio::OutputStream;
+}
+
+impl ObjectImpl for HlsBaseSinkGioOutputStream {}
+
+impl OutputStreamImpl for HlsBaseSinkGioOutputStream {
+    fn write(
+        &self,
+        buffer: &[u8],
+        cancellable: Option<&gio::Cancellable>,
+    ) -> Result<usize, glib::Error> {
+        let stream = self.stream.lock().unwrap();
+        if let Some(ref s) = *stream {
+            s.write_all(buffer, cancellable)?;
+            let mut out_bytes = self.out_bytes.lock().unwrap();
+            *out_bytes += buffer.len();
+            return Ok(buffer.len());
+        }
+
+        Ok(0)
     }
 
-    pub fn as_output_stream(&self) -> gio::OutputStream {
-        self.stream.clone()
+    fn close(&self, cancellable: Option<&gio::Cancellable>) -> Result<(), glib::Error> {
+        let stream = self.stream.lock().unwrap().take();
+        if let Some(ref s) = stream {
+            s.close(cancellable)?;
+        }
+
+        Ok(())
+    }
+
+    fn flush(&self, cancellable: Option<&gio::Cancellable>) -> Result<(), glib::Error> {
+        let stream = self.stream.lock().unwrap();
+        if let Some(ref s) = *stream {
+            s.flush(cancellable)?;
+        }
+
+        Ok(())
+    }
+}
+
+impl super::HlsBaseSinkGioOutputStream {
+    pub fn new(stream: gio::OutputStream) -> Self {
+        let obj = glib::Object::new::<Self>();
+        *obj.imp().stream.lock().unwrap() = Some(stream);
+        obj
+    }
+
+    pub fn out_bytes(&self) -> usize {
+        let out_bytes = self.imp().out_bytes.lock().unwrap();
+        *out_bytes
     }
 }
 
@@ -118,7 +168,7 @@ pub struct PlaylistContext {
 #[derive(Default)]
 pub struct State {
     context: Option<PlaylistContext>,
-    stream: Option<GioOutputStream>,
+    stream: Option<super::HlsBaseSinkGioOutputStream>,
 }
 
 #[derive(Default)]
@@ -434,21 +484,23 @@ impl HlsBaseSink {
             Some((stream, location))
         } else {
             let location = settings.single_media_file.as_ref().unwrap().clone();
-
-            let stream = if let Some(s) = &state.stream {
-                s.as_output_stream()
-            } else {
+            if state.stream.is_none() {
                 let stream = self.obj().emit_by_name::<Option<gio::OutputStream>>(
                     SIGNAL_GET_FRAGMENT_STREAM,
                     &[&location],
                 )?;
 
-                state.stream = Some(GioOutputStream::new(stream.clone()));
+                let gios = super::HlsBaseSinkGioOutputStream::new(stream);
+                let stream = gios.upcast_ref::<gio::OutputStream>().clone();
 
-                stream
-            };
+                state.stream = Some(gios);
 
-            Some((stream, location))
+                Some((stream, location))
+            } else {
+                let gios = state.stream.as_ref().unwrap();
+                let stream = gios.upcast_ref::<gio::OutputStream>().clone();
+                Some((stream, location))
+            }
         }
     }
 
@@ -699,6 +751,11 @@ impl HlsBaseSink {
         settings.single_media_file.is_some()
     }
 
+    pub fn out_bytes(&self) -> usize {
+        let state = self.state.lock().unwrap();
+        state.stream.as_ref().unwrap().out_bytes()
+    }
+
     fn byte_ranges(
         &self,
         context: &PlaylistContext,

net/hlssink3/src/hlssink3/imp.rs

@@ -17,8 +17,6 @@ use gst::glib;
 use gst::prelude::*;
 use gst::subclass::prelude::*;
 use m3u8_rs::{MediaPlaylist, MediaPlaylistType, MediaSegment};
-use std::io::Write;
-use std::sync::Arc;
 use std::sync::LazyLock;
 use std::sync::Mutex;
 
@@ -38,89 +36,6 @@ macro_rules! base_imp {
     };
 }
 
-// `splitmuxsink` does not know the size of the fragment written out by
-// the muxer. We track this by using a wrapper around the OutputStream.
-// Implementing Write trait for this allows passing it to a WriteOutputStream.
-#[derive(Clone)]
-struct CountingOutputStream {
-    inner: Arc<Mutex<CountingOutputStreamInner>>,
-}
-
-impl CountingOutputStream {
-    pub fn new(stream: gio::OutputStream) -> Self {
-        Self {
-            inner: Arc::new(Mutex::new(CountingOutputStreamInner::new(stream))),
-        }
-    }
-
-    pub fn out_bytes(&self) -> u64 {
-        let inner = self.inner.lock().unwrap();
-        inner.out_bytes()
-    }
-}
-
-impl Write for CountingOutputStream {
-    fn write(&mut self, buf: &[u8]) -> std::io::Result<usize> {
-        let mut inner = self.inner.lock().unwrap();
-        inner.write(buf)
-    }
-
-    fn flush(&mut self) -> std::io::Result<()> {
-        let mut inner = self.inner.lock().unwrap();
-        inner.flush()
-    }
-}
-
-struct CountingOutputStreamInner {
-    stream: gio::OutputStream,
-    data: Vec<u8>,
-    out_bytes: u64,
-}
-
-unsafe impl Send for CountingOutputStreamInner {}
-unsafe impl Sync for CountingOutputStreamInner {}
-
-impl CountingOutputStreamInner {
-    pub fn new(stream: gio::OutputStream) -> Self {
-        Self {
-            stream,
-            data: Vec::new(),
-            out_bytes: 0,
-        }
-    }
-
-    pub fn out_bytes(&self) -> u64 {
-        self.out_bytes
-    }
-
-    fn inner_flush(&mut self) -> std::io::Result<()> {
-        let data_len = self.data.len() as u64;
-        if data_len == 0 {
-            return Ok(());
-        }
-
-        let data: Vec<u8> = self.data.drain(0..).collect();
-
-        let mut s = self.stream.clone().into_write();
-        s.write(&data).unwrap();
-
-        self.out_bytes = data_len;
-
-        Ok(())
-    }
-}
-
-impl Write for CountingOutputStreamInner {
-    fn write(&mut self, buf: &[u8]) -> std::io::Result<usize> {
-        self.data.extend_from_slice(buf);
-        Ok(buf.len())
-    }
-
-    fn flush(&mut self) -> std::io::Result<()> {
-        self.inner_flush()
-    }
-}
-
 /// Offset between NTP and UNIX epoch in seconds.
 /// NTP = UNIX + NTP_UNIX_OFFSET.
 const NTP_UNIX_OFFSET: u64 = 2_208_988_800;
@@ -246,7 +161,6 @@ struct HlsSink3State {
     fragment_running_time: Option<gst::ClockTime>,
     current_segment_location: Option<String>,
     fragment_start_timestamp: Option<DateTime<Utc>>,
-    stream: Option<CountingOutputStream>,
     offset: u64,
 }
 
@@ -630,7 +544,25 @@ impl HlsSink3 {
             (false, playlist_type)
         };
 
-        let version = if i_frames_only || base_imp!(self).is_single_media_file() {
+        let is_single_media_file = base_imp!(self).is_single_media_file();
+        if is_single_media_file {
+            // `splitmuxsink` will stop the sink on every fragment,
+            // don't do that for single media file case as we need
+            // to keep the stream around for writing.
+            let giostreamsink = self.settings.lock().unwrap().giostreamsink.clone();
+            if giostreamsink.has_property_with_type("close-on-stop", bool::static_type()) {
+                giostreamsink.set_property("close-on-stop", false);
+            } else {
+                gst::element_imp_error!(
+                    self,
+                    gst::ResourceError::Settings,
+                    ("Invalid configuration"),
+                    ["Single media file support with hlssink3 needs GStreamer 1.24 or later"]
+                );
+            }
+        }
+
+        let version = if i_frames_only || is_single_media_file {
             Some(4)
         } else {
             Some(3)
@@ -668,29 +600,17 @@ impl HlsSink3 {
         state.fragment_running_time = running_time;
 
         let settings = self.settings.lock().unwrap();
-        let stream = if base_imp!(self).is_single_media_file() {
-            if state.stream.is_none() {
-                let gios = CountingOutputStream::new(fragment_stream);
-                let stream =
-                    gio::WriteOutputStream::new(gios.clone()).upcast::<gio::OutputStream>();
-                state.stream = Some(gios);
-                stream
-            } else {
-                gio::WriteOutputStream::new(state.stream.as_ref().unwrap().clone())
-                    .upcast::<gio::OutputStream>()
-            }
-        } else {
-            gst::info!(
-                CAT,
-                imp = self,
-                "New segment location: {:?}",
-                segment_file_location,
-            );
 
-            fragment_stream
-        };
+        gst::info!(
+            CAT,
+            imp = self,
+            "New segment location: {:?}",
+            segment_file_location,
+        );
 
-        settings.giostreamsink.set_property("stream", &stream);
+        settings
+            .giostreamsink
+            .set_property("stream", &fragment_stream);
 
         Ok(segment_file_location)
     }
@@ -745,8 +665,8 @@ impl HlsSink3 {
         let running_time = state.fragment_running_time;
         let fragment_start_timestamp = state.fragment_start_timestamp.take();
         let byte_range = if base_imp!(self).is_single_media_file() {
-            let length = state.stream.as_ref().unwrap().out_bytes();
             let offset = state.offset;
+            let length = base_imp!(self).out_bytes() as u64 - offset;
             state.offset += length;
             Some(m3u8_rs::ByteRange {
                 length,

net/hlssink3/src/lib.rs

@@ -19,6 +19,13 @@ pub mod hlscmafsink;
 pub mod hlssink3;
 mod playlist;
 
+glib::wrapper! {
+    pub struct HlsBaseSinkGioOutputStream(ObjectSubclass<hlsbasesink::HlsBaseSinkGioOutputStream>) @extends gio::OutputStream;
+}
+
+unsafe impl Send for HlsBaseSinkGioOutputStream {}
+unsafe impl Sync for HlsBaseSinkGioOutputStream {}
+
 glib::wrapper! {
     pub struct HlsBaseSink(ObjectSubclass<hlsbasesink::HlsBaseSink>) @extends gst::Bin, gst::Element, gst::Object;
 }