Use builders for the key-unit and still-frame events too

gstreamer-video/src/video_event.rs

@@ -7,31 +7,128 @@
 // except according to those terms.
 
 use ffi;
+use gst_ffi;
 
 use gst;
 use gst::MiniObject;
 use glib::translate::{from_glib, from_glib_full, ToGlib};
+use glib::ToSendValue;
 
 pub fn is_force_key_unit_event(event: &gst::EventRef) -> bool {
     unsafe { from_glib(ffi::gst_video_event_is_force_key_unit(event.as_mut_ptr())) }
 }
 
-pub fn new_downstream_force_key_unit_event(
+// FIXME: Copy from gstreamer/src/event.rs
+macro_rules! event_builder_generic_impl {
+    ($new_fn:expr) => {
+        pub fn seqnum(self, seqnum: gst::Seqnum) -> Self {
+            Self {
+                seqnum: Some(seqnum),
+                .. self
+            }
+        }
+
+        pub fn running_time_offset(self, running_time_offset: i64) -> Self {
+            Self {
+                running_time_offset: Some(running_time_offset),
+                .. self
+            }
+        }
+
+        pub fn other_fields(self, other_fields: &[(&'a str, &'a ToSendValue)]) -> Self {
+            Self {
+                other_fields: self.other_fields.iter().cloned()
+                    .chain(other_fields.iter().cloned())
+                    .collect(),
+                .. self
+            }
+        }
+
+        pub fn build(mut self) -> gst::Event {
+            assert_initialized_main_thread!();
+            unsafe {
+                let event = $new_fn(&mut self);
+                if let Some(seqnum) = self.seqnum {
+                    gst_ffi::gst_event_set_seqnum(event, seqnum.to_glib());
+                }
+
+                if let Some(running_time_offset) = self.running_time_offset {
+                    gst_ffi::gst_event_set_running_time_offset(event, running_time_offset);
+                }
+
+                {
+                    let s = gst::StructureRef::from_glib_borrow_mut(
+                        gst_ffi::gst_event_writable_structure(event)
+                    );
+
+                    for (k, v) in self.other_fields {
+                        s.set_value(k, v.to_send_value());
+                    }
+                }
+
+                from_glib_full(event)
+            }
+        }
+    }
+}
+
+pub fn new_downstream_force_key_unit_event<'a>(
     timestamp: gst::ClockTime,
     stream_time: gst::ClockTime,
     running_time: gst::ClockTime,
     all_headers: bool,
     count: u32,
-) -> gst::Event {
-    unsafe {
-        from_glib_full(ffi::gst_video_event_new_downstream_force_key_unit(
-            timestamp.to_glib(),
-            stream_time.to_glib(),
-            running_time.to_glib(),
-            all_headers.to_glib(),
+) -> DownstreamForceKeyUnitEventBuilder<'a> {
+    DownstreamForceKeyUnitEventBuilder::new(
+        timestamp,
+        stream_time,
+        running_time,
+        all_headers,
         count,
-        ))
+    )
 }
+
+pub struct DownstreamForceKeyUnitEventBuilder<'a> {
+    seqnum: Option<gst::Seqnum>,
+    running_time_offset: Option<i64>,
+    other_fields: Vec<(&'a str, &'a ToSendValue)>,
+    timestamp: gst::ClockTime,
+    stream_time: gst::ClockTime,
+    running_time: gst::ClockTime,
+    all_headers: bool,
+    count: u32,
+}
+
+impl<'a> DownstreamForceKeyUnitEventBuilder<'a> {
+    fn new(
+        timestamp: gst::ClockTime,
+        stream_time: gst::ClockTime,
+        running_time: gst::ClockTime,
+        all_headers: bool,
+        count: u32,
+    ) -> Self {
+        skip_assert_initialized!();
+        Self {
+            seqnum: None,
+            running_time_offset: None,
+            other_fields: Vec::new(),
+            timestamp: timestamp,
+            stream_time: stream_time,
+            running_time: running_time,
+            all_headers: all_headers,
+            count: count,
+        }
+    }
+
+    event_builder_generic_impl!(|s: &mut Self| {
+        ffi::gst_video_event_new_downstream_force_key_unit(
+            s.timestamp.to_glib(),
+            s.stream_time.to_glib(),
+            s.running_time.to_glib(),
+            s.all_headers.to_glib(),
+            s.count,
+        )
+    });
 }
 
 #[derive(Clone, PartialEq, Eq, Debug)]
@@ -75,18 +172,43 @@ pub fn parse_downstream_force_key_unit_event(
     }
 }
 
-pub fn new_upstream_force_key_unit_event(
+pub fn new_upstream_force_key_unit_event<'a>(
     running_time: gst::ClockTime,
     all_headers: bool,
     count: u32,
-) -> gst::Event {
-    unsafe {
-        from_glib_full(ffi::gst_video_event_new_upstream_force_key_unit(
-            running_time.to_glib(),
-            all_headers.to_glib(),
-            count,
-        ))
+) -> UpstreamForceKeyUnitEventBuilder<'a> {
+    UpstreamForceKeyUnitEventBuilder::new(running_time, all_headers, count)
 }
+
+pub struct UpstreamForceKeyUnitEventBuilder<'a> {
+    seqnum: Option<gst::Seqnum>,
+    running_time_offset: Option<i64>,
+    other_fields: Vec<(&'a str, &'a ToSendValue)>,
+    running_time: gst::ClockTime,
+    all_headers: bool,
+    count: u32,
+}
+
+impl<'a> UpstreamForceKeyUnitEventBuilder<'a> {
+    fn new(running_time: gst::ClockTime, all_headers: bool, count: u32) -> Self {
+        skip_assert_initialized!();
+        Self {
+            seqnum: None,
+            running_time_offset: None,
+            other_fields: Vec::new(),
+            running_time: running_time,
+            all_headers: all_headers,
+            count: count,
+        }
+    }
+
+    event_builder_generic_impl!(|s: &mut Self| {
+        ffi::gst_video_event_new_upstream_force_key_unit(
+            s.running_time.to_glib(),
+            s.all_headers.to_glib(),
+            s.count,
+        )
+    });
 }
 
 #[derive(Clone, PartialEq, Eq, Debug)]
@@ -136,8 +258,31 @@ pub fn parse_force_key_unit_event(event: &gst::EventRef) -> Option<ForceKeyUnitE
     }
 }
 
-pub fn new_still_frame_event(in_still: bool) -> gst::Event {
-    unsafe { from_glib_full(ffi::gst_video_event_new_still_frame(in_still.to_glib())) }
+pub fn new_still_frame_event<'a>(in_still: bool) -> StillFrameEventBuilder<'a> {
+    StillFrameEventBuilder::new(in_still)
+}
+
+pub struct StillFrameEventBuilder<'a> {
+    seqnum: Option<gst::Seqnum>,
+    running_time_offset: Option<i64>,
+    other_fields: Vec<(&'a str, &'a ToSendValue)>,
+    in_still: bool,
+}
+
+impl<'a> StillFrameEventBuilder<'a> {
+    fn new(in_still: bool) -> Self {
+        skip_assert_initialized!();
+        Self {
+            seqnum: None,
+            running_time_offset: None,
+            other_fields: Vec::new(),
+            in_still: in_still,
+        }
+    }
+
+    event_builder_generic_impl!(|s: &mut Self| {
+        ffi::gst_video_event_new_still_frame(s.in_still.to_glib())
+    });
 }
 
 #[derive(Clone, PartialEq, Eq, Debug)]