rtp/gir: Manually implement RtpHeaderExtension read() and write()

The array size is now provided since [1], yet mutability and `*Ref`
makes it impossible to generate these functions properly.  Implement
them by hand.

[1]: https://gitlab.freedesktop.org/gstreamer/gst-plugins-base/-/merge_requests/1190

gstreamer-rtp/Gir.toml

@@ -65,11 +65,11 @@ status = "manual"
 [[object]]
 name = "GstRtp.RTPHeaderExtension"
 status = "generate"
+manual_traits = ["RTPHeaderExtensionExtManual"]
     [[object.function]]
     pattern = "read|write"
-    # Until 1.19.2: `data` field lacks`array size` annotation:
-    # https://gitlab.freedesktop.org/gstreamer/gst-plugins-base/-/merge_requests/1190
-    ignore = true
+    # Mutability of BufferRef
+    manual = true
 
     [[object.function]]
     name = "get_sdp_caps_field_name"

gstreamer-rtp/src/lib.rs

@@ -28,6 +28,9 @@ pub use crate::auto::*;
 
 pub mod rtp_buffer;
 pub use crate::rtp_buffer::{compare_seqnum, RTPBuffer};
+#[cfg(any(feature = "v1_20", feature = "dox"))]
+#[cfg_attr(feature = "dox", doc(cfg(feature = "v1_20")))]
+pub mod rtp_header_extension;
 
 // Re-export all the traits in a prelude module, so that applications
 // can always "use gst_rtp::prelude::*" without getting conflicts
@@ -38,4 +41,7 @@ pub mod prelude {
     pub use crate::auto::traits::*;
 
     pub use crate::rtp_buffer::RTPBufferExt;
+    #[cfg(any(feature = "v1_20", feature = "dox"))]
+    #[cfg_attr(feature = "dox", doc(cfg(feature = "v1_20")))]
+    pub use crate::rtp_header_extension::RTPHeaderExtensionExtManual;
 }

gstreamer-rtp/src/rtp_header_extension.rs

@@ -0,0 +1,63 @@
+use crate::RTPHeaderExtension;
+use crate::RTPHeaderExtensionFlags;
+use glib::object::IsA;
+use glib::translate::*;
+
+pub trait RTPHeaderExtensionExtManual: 'static {
+    #[doc(alias = "gst_rtp_header_extension_read")]
+    fn read(
+        &self,
+        read_flags: RTPHeaderExtensionFlags,
+        data: &[u8],
+        buffer: &mut gst::BufferRef,
+    ) -> bool;
+
+    #[doc(alias = "gst_rtp_header_extension_write")]
+    fn write(
+        &self,
+        input_meta: &gst::Buffer,
+        write_flags: RTPHeaderExtensionFlags,
+        output: &mut gst::BufferRef,
+        data: &mut [u8],
+    ) -> usize;
+}
+
+impl<O: IsA<RTPHeaderExtension>> RTPHeaderExtensionExtManual for O {
+    fn read(
+        &self,
+        read_flags: RTPHeaderExtensionFlags,
+        data: &[u8],
+        buffer: &mut gst::BufferRef,
+    ) -> bool {
+        let size = data.len() as usize;
+        unsafe {
+            from_glib(ffi::gst_rtp_header_extension_read(
+                self.as_ref().to_glib_none().0,
+                read_flags.into_glib(),
+                data.to_glib_none().0,
+                size,
+                buffer.as_mut_ptr(),
+            ))
+        }
+    }
+
+    fn write(
+        &self,
+        input_meta: &gst::Buffer,
+        write_flags: RTPHeaderExtensionFlags,
+        output: &mut gst::BufferRef,
+        data: &mut [u8],
+    ) -> usize {
+        let size = data.len() as usize;
+        unsafe {
+            ffi::gst_rtp_header_extension_write(
+                self.as_ref().to_glib_none().0,
+                input_meta.to_glib_none().0,
+                write_flags.into_glib(),
+                output.as_mut_ptr(),
+                data.to_glib_none().0,
+                size,
+            )
+        }
+    }
+}