gio/auto/
output_stream.rs

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// This file was generated by gir (https://github.com/gtk-rs/gir)
// from gir-files (https://github.com/gtk-rs/gir-files)
// DO NOT EDIT

use crate::{ffi, AsyncResult, Cancellable, InputStream, OutputStreamSpliceFlags};
use glib::{prelude::*, translate::*};
use std::{boxed::Box as Box_, pin::Pin};

glib::wrapper! {
    /// `GOutputStream` is a base class for implementing streaming output.
    ///
    /// It has functions to write to a stream ([`OutputStreamExt::write()`][crate::prelude::OutputStreamExt::write()]),
    /// to close a stream ([`OutputStreamExt::close()`][crate::prelude::OutputStreamExt::close()]) and to flush pending
    /// writes ([`OutputStreamExt::flush()`][crate::prelude::OutputStreamExt::flush()]).
    ///
    /// To copy the content of an input stream to an output stream without
    /// manually handling the reads and writes, use [`OutputStreamExt::splice()`][crate::prelude::OutputStreamExt::splice()].
    ///
    /// See the documentation for [`IOStream`][crate::IOStream] for details of thread safety
    /// of streaming APIs.
    ///
    /// All of these functions have async variants too.
    ///
    /// All classes derived from `GOutputStream` *should* implement synchronous
    /// writing, splicing, flushing and closing streams, but *may* implement
    /// asynchronous versions.
    ///
    /// This is an Abstract Base Class, you cannot instantiate it.
    ///
    /// # Implements
    ///
    /// [`OutputStreamExt`][trait@crate::prelude::OutputStreamExt], [`trait@glib::ObjectExt`], [`OutputStreamExtManual`][trait@crate::prelude::OutputStreamExtManual]
    #[doc(alias = "GOutputStream")]
    pub struct OutputStream(Object<ffi::GOutputStream, ffi::GOutputStreamClass>);

    match fn {
        type_ => || ffi::g_output_stream_get_type(),
    }
}

impl OutputStream {
    pub const NONE: Option<&'static OutputStream> = None;
}

mod sealed {
    pub trait Sealed {}
    impl<T: super::IsA<super::OutputStream>> Sealed for T {}
}

/// Trait containing all [`struct@OutputStream`] methods.
///
/// # Implementors
///
/// [`FileOutputStream`][struct@crate::FileOutputStream], [`FilterOutputStream`][struct@crate::FilterOutputStream], [`MemoryOutputStream`][struct@crate::MemoryOutputStream], [`OutputStream`][struct@crate::OutputStream], [`PollableOutputStream`][struct@crate::PollableOutputStream], [`UnixOutputStream`][struct@crate::UnixOutputStream]
pub trait OutputStreamExt: IsA<OutputStream> + sealed::Sealed + 'static {
    /// Clears the pending flag on @self.
    #[doc(alias = "g_output_stream_clear_pending")]
    fn clear_pending(&self) {
        unsafe {
            ffi::g_output_stream_clear_pending(self.as_ref().to_glib_none().0);
        }
    }

    /// Closes the stream, releasing resources related to it.
    ///
    /// Once the stream is closed, all other operations will return [`IOErrorEnum::Closed`][crate::IOErrorEnum::Closed].
    /// Closing a stream multiple times will not return an error.
    ///
    /// Closing a stream will automatically flush any outstanding buffers in the
    /// stream.
    ///
    /// Streams will be automatically closed when the last reference
    /// is dropped, but you might want to call this function to make sure
    /// resources are released as early as possible.
    ///
    /// Some streams might keep the backing store of the stream (e.g. a file descriptor)
    /// open after the stream is closed. See the documentation for the individual
    /// stream for details.
    ///
    /// On failure the first error that happened will be reported, but the close
    /// operation will finish as much as possible. A stream that failed to
    /// close will still return [`IOErrorEnum::Closed`][crate::IOErrorEnum::Closed] for all operations. Still, it
    /// is important to check and report the error to the user, otherwise
    /// there might be a loss of data as all data might not be written.
    ///
    /// If @cancellable is not [`None`], then the operation can be cancelled by
    /// triggering the cancellable object from another thread. If the operation
    /// was cancelled, the error [`IOErrorEnum::Cancelled`][crate::IOErrorEnum::Cancelled] will be returned.
    /// Cancelling a close will still leave the stream closed, but there some streams
    /// can use a faster close that doesn't block to e.g. check errors. On
    /// cancellation (as with any error) there is no guarantee that all written
    /// data will reach the target.
    /// ## `cancellable`
    /// optional cancellable object
    ///
    /// # Returns
    ///
    /// [`true`] on success, [`false`] on failure
    #[doc(alias = "g_output_stream_close")]
    fn close(&self, cancellable: Option<&impl IsA<Cancellable>>) -> Result<(), glib::Error> {
        unsafe {
            let mut error = std::ptr::null_mut();
            let is_ok = ffi::g_output_stream_close(
                self.as_ref().to_glib_none().0,
                cancellable.map(|p| p.as_ref()).to_glib_none().0,
                &mut error,
            );
            debug_assert_eq!(is_ok == glib::ffi::GFALSE, !error.is_null());
            if error.is_null() {
                Ok(())
            } else {
                Err(from_glib_full(error))
            }
        }
    }

    /// Requests an asynchronous close of the stream, releasing resources
    /// related to it. When the operation is finished @callback will be
    /// called. You can then call g_output_stream_close_finish() to get
    /// the result of the operation.
    ///
    /// For behaviour details see g_output_stream_close().
    ///
    /// The asynchronous methods have a default fallback that uses threads
    /// to implement asynchronicity, so they are optional for inheriting
    /// classes. However, if you override one you must override all.
    /// ## `io_priority`
    /// the io priority of the request.
    /// ## `cancellable`
    /// optional cancellable object
    /// ## `callback`
    /// a #GAsyncReadyCallback
    ///   to call when the request is satisfied
    #[doc(alias = "g_output_stream_close_async")]
    fn close_async<P: FnOnce(Result<(), glib::Error>) + 'static>(
        &self,
        io_priority: glib::Priority,
        cancellable: Option<&impl IsA<Cancellable>>,
        callback: P,
    ) {
        let main_context = glib::MainContext::ref_thread_default();
        let is_main_context_owner = main_context.is_owner();
        let has_acquired_main_context = (!is_main_context_owner)
            .then(|| main_context.acquire().ok())
            .flatten();
        assert!(
            is_main_context_owner || has_acquired_main_context.is_some(),
            "Async operations only allowed if the thread is owning the MainContext"
        );

        let user_data: Box_<glib::thread_guard::ThreadGuard<P>> =
            Box_::new(glib::thread_guard::ThreadGuard::new(callback));
        unsafe extern "C" fn close_async_trampoline<
            P: FnOnce(Result<(), glib::Error>) + 'static,
        >(
            _source_object: *mut glib::gobject_ffi::GObject,
            res: *mut crate::ffi::GAsyncResult,
            user_data: glib::ffi::gpointer,
        ) {
            let mut error = std::ptr::null_mut();
            let _ = ffi::g_output_stream_close_finish(_source_object as *mut _, res, &mut error);
            let result = if error.is_null() {
                Ok(())
            } else {
                Err(from_glib_full(error))
            };
            let callback: Box_<glib::thread_guard::ThreadGuard<P>> =
                Box_::from_raw(user_data as *mut _);
            let callback: P = callback.into_inner();
            callback(result);
        }
        let callback = close_async_trampoline::<P>;
        unsafe {
            ffi::g_output_stream_close_async(
                self.as_ref().to_glib_none().0,
                io_priority.into_glib(),
                cancellable.map(|p| p.as_ref()).to_glib_none().0,
                Some(callback),
                Box_::into_raw(user_data) as *mut _,
            );
        }
    }

    fn close_future(
        &self,
        io_priority: glib::Priority,
    ) -> Pin<Box_<dyn std::future::Future<Output = Result<(), glib::Error>> + 'static>> {
        Box_::pin(crate::GioFuture::new(
            self,
            move |obj, cancellable, send| {
                obj.close_async(io_priority, Some(cancellable), move |res| {
                    send.resolve(res);
                });
            },
        ))
    }

    /// Forces a write of all user-space buffered data for the given
    /// @self. Will block during the operation. Closing the stream will
    /// implicitly cause a flush.
    ///
    /// This function is optional for inherited classes.
    ///
    /// If @cancellable is not [`None`], then the operation can be cancelled by
    /// triggering the cancellable object from another thread. If the operation
    /// was cancelled, the error [`IOErrorEnum::Cancelled`][crate::IOErrorEnum::Cancelled] will be returned.
    /// ## `cancellable`
    /// optional cancellable object
    ///
    /// # Returns
    ///
    /// [`true`] on success, [`false`] on error
    #[doc(alias = "g_output_stream_flush")]
    fn flush(&self, cancellable: Option<&impl IsA<Cancellable>>) -> Result<(), glib::Error> {
        unsafe {
            let mut error = std::ptr::null_mut();
            let is_ok = ffi::g_output_stream_flush(
                self.as_ref().to_glib_none().0,
                cancellable.map(|p| p.as_ref()).to_glib_none().0,
                &mut error,
            );
            debug_assert_eq!(is_ok == glib::ffi::GFALSE, !error.is_null());
            if error.is_null() {
                Ok(())
            } else {
                Err(from_glib_full(error))
            }
        }
    }

    /// Forces an asynchronous write of all user-space buffered data for
    /// the given @self.
    /// For behaviour details see g_output_stream_flush().
    ///
    /// When the operation is finished @callback will be
    /// called. You can then call g_output_stream_flush_finish() to get the
    /// result of the operation.
    /// ## `io_priority`
    /// the io priority of the request.
    /// ## `cancellable`
    /// optional #GCancellable object, [`None`] to ignore.
    /// ## `callback`
    /// a #GAsyncReadyCallback
    ///   to call when the request is satisfied
    #[doc(alias = "g_output_stream_flush_async")]
    fn flush_async<P: FnOnce(Result<(), glib::Error>) + 'static>(
        &self,
        io_priority: glib::Priority,
        cancellable: Option<&impl IsA<Cancellable>>,
        callback: P,
    ) {
        let main_context = glib::MainContext::ref_thread_default();
        let is_main_context_owner = main_context.is_owner();
        let has_acquired_main_context = (!is_main_context_owner)
            .then(|| main_context.acquire().ok())
            .flatten();
        assert!(
            is_main_context_owner || has_acquired_main_context.is_some(),
            "Async operations only allowed if the thread is owning the MainContext"
        );

        let user_data: Box_<glib::thread_guard::ThreadGuard<P>> =
            Box_::new(glib::thread_guard::ThreadGuard::new(callback));
        unsafe extern "C" fn flush_async_trampoline<
            P: FnOnce(Result<(), glib::Error>) + 'static,
        >(
            _source_object: *mut glib::gobject_ffi::GObject,
            res: *mut crate::ffi::GAsyncResult,
            user_data: glib::ffi::gpointer,
        ) {
            let mut error = std::ptr::null_mut();
            let _ = ffi::g_output_stream_flush_finish(_source_object as *mut _, res, &mut error);
            let result = if error.is_null() {
                Ok(())
            } else {
                Err(from_glib_full(error))
            };
            let callback: Box_<glib::thread_guard::ThreadGuard<P>> =
                Box_::from_raw(user_data as *mut _);
            let callback: P = callback.into_inner();
            callback(result);
        }
        let callback = flush_async_trampoline::<P>;
        unsafe {
            ffi::g_output_stream_flush_async(
                self.as_ref().to_glib_none().0,
                io_priority.into_glib(),
                cancellable.map(|p| p.as_ref()).to_glib_none().0,
                Some(callback),
                Box_::into_raw(user_data) as *mut _,
            );
        }
    }

    fn flush_future(
        &self,
        io_priority: glib::Priority,
    ) -> Pin<Box_<dyn std::future::Future<Output = Result<(), glib::Error>> + 'static>> {
        Box_::pin(crate::GioFuture::new(
            self,
            move |obj, cancellable, send| {
                obj.flush_async(io_priority, Some(cancellable), move |res| {
                    send.resolve(res);
                });
            },
        ))
    }

    /// Checks if an output stream has pending actions.
    ///
    /// # Returns
    ///
    /// [`true`] if @self has pending actions.
    #[doc(alias = "g_output_stream_has_pending")]
    fn has_pending(&self) -> bool {
        unsafe {
            from_glib(ffi::g_output_stream_has_pending(
                self.as_ref().to_glib_none().0,
            ))
        }
    }

    /// Checks if an output stream has already been closed.
    ///
    /// # Returns
    ///
    /// [`true`] if @self is closed. [`false`] otherwise.
    #[doc(alias = "g_output_stream_is_closed")]
    fn is_closed(&self) -> bool {
        unsafe {
            from_glib(ffi::g_output_stream_is_closed(
                self.as_ref().to_glib_none().0,
            ))
        }
    }

    /// Checks if an output stream is being closed. This can be
    /// used inside e.g. a flush implementation to see if the
    /// flush (or other i/o operation) is called from within
    /// the closing operation.
    ///
    /// # Returns
    ///
    /// [`true`] if @self is being closed. [`false`] otherwise.
    #[doc(alias = "g_output_stream_is_closing")]
    fn is_closing(&self) -> bool {
        unsafe {
            from_glib(ffi::g_output_stream_is_closing(
                self.as_ref().to_glib_none().0,
            ))
        }
    }

    //#[doc(alias = "g_output_stream_printf")]
    //fn printf(&self, cancellable: Option<&impl IsA<Cancellable>>, error: &mut glib::Error, format: &str, : /*Unknown conversion*//*Unimplemented*/Basic: VarArgs) -> Option<usize> {
    //    unsafe { TODO: call ffi:g_output_stream_printf() }
    //}

    /// Sets @self to have actions pending. If the pending flag is
    /// already set or @self is closed, it will return [`false`] and set
    /// @error.
    ///
    /// # Returns
    ///
    /// [`true`] if pending was previously unset and is now set.
    #[doc(alias = "g_output_stream_set_pending")]
    fn set_pending(&self) -> Result<(), glib::Error> {
        unsafe {
            let mut error = std::ptr::null_mut();
            let is_ok =
                ffi::g_output_stream_set_pending(self.as_ref().to_glib_none().0, &mut error);
            debug_assert_eq!(is_ok == glib::ffi::GFALSE, !error.is_null());
            if error.is_null() {
                Ok(())
            } else {
                Err(from_glib_full(error))
            }
        }
    }

    /// Splices an input stream into an output stream.
    /// ## `source`
    /// a #GInputStream.
    /// ## `flags`
    /// a set of #GOutputStreamSpliceFlags.
    /// ## `cancellable`
    /// optional #GCancellable object, [`None`] to ignore.
    ///
    /// # Returns
    ///
    /// a #gssize containing the size of the data spliced, or
    ///     -1 if an error occurred. Note that if the number of bytes
    ///     spliced is greater than `G_MAXSSIZE`, then that will be
    ///     returned, and there is no way to determine the actual number
    ///     of bytes spliced.
    #[doc(alias = "g_output_stream_splice")]
    fn splice(
        &self,
        source: &impl IsA<InputStream>,
        flags: OutputStreamSpliceFlags,
        cancellable: Option<&impl IsA<Cancellable>>,
    ) -> Result<isize, glib::Error> {
        unsafe {
            let mut error = std::ptr::null_mut();
            let ret = ffi::g_output_stream_splice(
                self.as_ref().to_glib_none().0,
                source.as_ref().to_glib_none().0,
                flags.into_glib(),
                cancellable.map(|p| p.as_ref()).to_glib_none().0,
                &mut error,
            );
            if error.is_null() {
                Ok(ret)
            } else {
                Err(from_glib_full(error))
            }
        }
    }

    /// Splices a stream asynchronously.
    /// When the operation is finished @callback will be called.
    /// You can then call g_output_stream_splice_finish() to get the
    /// result of the operation.
    ///
    /// For the synchronous, blocking version of this function, see
    /// g_output_stream_splice().
    /// ## `source`
    /// a #GInputStream.
    /// ## `flags`
    /// a set of #GOutputStreamSpliceFlags.
    /// ## `io_priority`
    /// the io priority of the request.
    /// ## `cancellable`
    /// optional #GCancellable object, [`None`] to ignore.
    /// ## `callback`
    /// a #GAsyncReadyCallback
    ///   to call when the request is satisfied
    #[doc(alias = "g_output_stream_splice_async")]
    fn splice_async<P: FnOnce(Result<isize, glib::Error>) + 'static>(
        &self,
        source: &impl IsA<InputStream>,
        flags: OutputStreamSpliceFlags,
        io_priority: glib::Priority,
        cancellable: Option<&impl IsA<Cancellable>>,
        callback: P,
    ) {
        let main_context = glib::MainContext::ref_thread_default();
        let is_main_context_owner = main_context.is_owner();
        let has_acquired_main_context = (!is_main_context_owner)
            .then(|| main_context.acquire().ok())
            .flatten();
        assert!(
            is_main_context_owner || has_acquired_main_context.is_some(),
            "Async operations only allowed if the thread is owning the MainContext"
        );

        let user_data: Box_<glib::thread_guard::ThreadGuard<P>> =
            Box_::new(glib::thread_guard::ThreadGuard::new(callback));
        unsafe extern "C" fn splice_async_trampoline<
            P: FnOnce(Result<isize, glib::Error>) + 'static,
        >(
            _source_object: *mut glib::gobject_ffi::GObject,
            res: *mut crate::ffi::GAsyncResult,
            user_data: glib::ffi::gpointer,
        ) {
            let mut error = std::ptr::null_mut();
            let ret = ffi::g_output_stream_splice_finish(_source_object as *mut _, res, &mut error);
            let result = if error.is_null() {
                Ok(ret)
            } else {
                Err(from_glib_full(error))
            };
            let callback: Box_<glib::thread_guard::ThreadGuard<P>> =
                Box_::from_raw(user_data as *mut _);
            let callback: P = callback.into_inner();
            callback(result);
        }
        let callback = splice_async_trampoline::<P>;
        unsafe {
            ffi::g_output_stream_splice_async(
                self.as_ref().to_glib_none().0,
                source.as_ref().to_glib_none().0,
                flags.into_glib(),
                io_priority.into_glib(),
                cancellable.map(|p| p.as_ref()).to_glib_none().0,
                Some(callback),
                Box_::into_raw(user_data) as *mut _,
            );
        }
    }

    fn splice_future(
        &self,
        source: &(impl IsA<InputStream> + Clone + 'static),
        flags: OutputStreamSpliceFlags,
        io_priority: glib::Priority,
    ) -> Pin<Box_<dyn std::future::Future<Output = Result<isize, glib::Error>> + 'static>> {
        let source = source.clone();
        Box_::pin(crate::GioFuture::new(
            self,
            move |obj, cancellable, send| {
                obj.splice_async(&source, flags, io_priority, Some(cancellable), move |res| {
                    send.resolve(res);
                });
            },
        ))
    }

    //#[doc(alias = "g_output_stream_vprintf")]
    //fn vprintf(&self, cancellable: Option<&impl IsA<Cancellable>>, error: &mut glib::Error, format: &str, args: /*Unknown conversion*//*Unimplemented*/Unsupported) -> Option<usize> {
    //    unsafe { TODO: call ffi:g_output_stream_vprintf() }
    //}

    /// Tries to write @count bytes from @buffer into the stream. Will block
    /// during the operation.
    ///
    /// If count is 0, returns 0 and does nothing. A value of @count
    /// larger than `G_MAXSSIZE` will cause a [`IOErrorEnum::InvalidArgument`][crate::IOErrorEnum::InvalidArgument] error.
    ///
    /// On success, the number of bytes written to the stream is returned.
    /// It is not an error if this is not the same as the requested size, as it
    /// can happen e.g. on a partial I/O error, or if there is not enough
    /// storage in the stream. All writes block until at least one byte
    /// is written or an error occurs; 0 is never returned (unless
    /// @count is 0).
    ///
    /// If @cancellable is not [`None`], then the operation can be cancelled by
    /// triggering the cancellable object from another thread. If the operation
    /// was cancelled, the error [`IOErrorEnum::Cancelled`][crate::IOErrorEnum::Cancelled] will be returned. If an
    /// operation was partially finished when the operation was cancelled the
    /// partial result will be returned, without an error.
    ///
    /// On error -1 is returned and @error is set accordingly.
    /// ## `buffer`
    /// the buffer containing the data to write.
    /// ## `cancellable`
    /// optional cancellable object
    ///
    /// # Returns
    ///
    /// Number of bytes written, or -1 on error
    #[doc(alias = "g_output_stream_write")]
    fn write(
        &self,
        buffer: &[u8],
        cancellable: Option<&impl IsA<Cancellable>>,
    ) -> Result<isize, glib::Error> {
        let count = buffer.len() as _;
        unsafe {
            let mut error = std::ptr::null_mut();
            let ret = ffi::g_output_stream_write(
                self.as_ref().to_glib_none().0,
                buffer.to_glib_none().0,
                count,
                cancellable.map(|p| p.as_ref()).to_glib_none().0,
                &mut error,
            );
            if error.is_null() {
                Ok(ret)
            } else {
                Err(from_glib_full(error))
            }
        }
    }

    /// A wrapper function for g_output_stream_write() which takes a
    /// #GBytes as input.  This can be more convenient for use by language
    /// bindings or in other cases where the refcounted nature of #GBytes
    /// is helpful over a bare pointer interface.
    ///
    /// However, note that this function may still perform partial writes,
    /// just like g_output_stream_write().  If that occurs, to continue
    /// writing, you will need to create a new #GBytes containing just the
    /// remaining bytes, using g_bytes_new_from_bytes(). Passing the same
    /// #GBytes instance multiple times potentially can result in duplicated
    /// data in the output stream.
    /// ## `bytes`
    /// the #GBytes to write
    /// ## `cancellable`
    /// optional cancellable object
    ///
    /// # Returns
    ///
    /// Number of bytes written, or -1 on error
    #[doc(alias = "g_output_stream_write_bytes")]
    fn write_bytes(
        &self,
        bytes: &glib::Bytes,
        cancellable: Option<&impl IsA<Cancellable>>,
    ) -> Result<isize, glib::Error> {
        unsafe {
            let mut error = std::ptr::null_mut();
            let ret = ffi::g_output_stream_write_bytes(
                self.as_ref().to_glib_none().0,
                bytes.to_glib_none().0,
                cancellable.map(|p| p.as_ref()).to_glib_none().0,
                &mut error,
            );
            if error.is_null() {
                Ok(ret)
            } else {
                Err(from_glib_full(error))
            }
        }
    }

    /// This function is similar to g_output_stream_write_async(), but
    /// takes a #GBytes as input.  Due to the refcounted nature of #GBytes,
    /// this allows the stream to avoid taking a copy of the data.
    ///
    /// However, note that this function may still perform partial writes,
    /// just like g_output_stream_write_async(). If that occurs, to continue
    /// writing, you will need to create a new #GBytes containing just the
    /// remaining bytes, using g_bytes_new_from_bytes(). Passing the same
    /// #GBytes instance multiple times potentially can result in duplicated
    /// data in the output stream.
    ///
    /// For the synchronous, blocking version of this function, see
    /// g_output_stream_write_bytes().
    /// ## `bytes`
    /// The bytes to write
    /// ## `io_priority`
    /// the io priority of the request.
    /// ## `cancellable`
    /// optional #GCancellable object, [`None`] to ignore.
    /// ## `callback`
    /// a #GAsyncReadyCallback
    ///   to call when the request is satisfied
    #[doc(alias = "g_output_stream_write_bytes_async")]
    fn write_bytes_async<P: FnOnce(Result<isize, glib::Error>) + 'static>(
        &self,
        bytes: &glib::Bytes,
        io_priority: glib::Priority,
        cancellable: Option<&impl IsA<Cancellable>>,
        callback: P,
    ) {
        let main_context = glib::MainContext::ref_thread_default();
        let is_main_context_owner = main_context.is_owner();
        let has_acquired_main_context = (!is_main_context_owner)
            .then(|| main_context.acquire().ok())
            .flatten();
        assert!(
            is_main_context_owner || has_acquired_main_context.is_some(),
            "Async operations only allowed if the thread is owning the MainContext"
        );

        let user_data: Box_<glib::thread_guard::ThreadGuard<P>> =
            Box_::new(glib::thread_guard::ThreadGuard::new(callback));
        unsafe extern "C" fn write_bytes_async_trampoline<
            P: FnOnce(Result<isize, glib::Error>) + 'static,
        >(
            _source_object: *mut glib::gobject_ffi::GObject,
            res: *mut crate::ffi::GAsyncResult,
            user_data: glib::ffi::gpointer,
        ) {
            let mut error = std::ptr::null_mut();
            let ret =
                ffi::g_output_stream_write_bytes_finish(_source_object as *mut _, res, &mut error);
            let result = if error.is_null() {
                Ok(ret)
            } else {
                Err(from_glib_full(error))
            };
            let callback: Box_<glib::thread_guard::ThreadGuard<P>> =
                Box_::from_raw(user_data as *mut _);
            let callback: P = callback.into_inner();
            callback(result);
        }
        let callback = write_bytes_async_trampoline::<P>;
        unsafe {
            ffi::g_output_stream_write_bytes_async(
                self.as_ref().to_glib_none().0,
                bytes.to_glib_none().0,
                io_priority.into_glib(),
                cancellable.map(|p| p.as_ref()).to_glib_none().0,
                Some(callback),
                Box_::into_raw(user_data) as *mut _,
            );
        }
    }

    fn write_bytes_future(
        &self,
        bytes: &glib::Bytes,
        io_priority: glib::Priority,
    ) -> Pin<Box_<dyn std::future::Future<Output = Result<isize, glib::Error>> + 'static>> {
        let bytes = bytes.clone();
        Box_::pin(crate::GioFuture::new(
            self,
            move |obj, cancellable, send| {
                obj.write_bytes_async(&bytes, io_priority, Some(cancellable), move |res| {
                    send.resolve(res);
                });
            },
        ))
    }
}

impl<O: IsA<OutputStream>> OutputStreamExt for O {}