gio/auto/

pollable_output_stream.rs

// 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, Cancellable, OutputStream};
use glib::{prelude::*, translate::*};

glib::wrapper! {
    /// `GPollableOutputStream` is implemented by [`OutputStream`][crate::OutputStream]s that
    /// can be polled for readiness to write. This can be used when
    /// interfacing with a non-GIO API that expects
    /// UNIX-file-descriptor-style asynchronous I/O rather than GIO-style.
    ///
    /// Some classes may implement `GPollableOutputStream` but have only certain
    /// instances of that class be pollable. If [`PollableOutputStreamExt::can_poll()`][crate::prelude::PollableOutputStreamExt::can_poll()]
    /// returns false, then the behavior of other `GPollableOutputStream` methods is
    /// undefined.
    ///
    /// # Implements
    ///
    /// [`PollableOutputStreamExt`][trait@crate::prelude::PollableOutputStreamExt], [`OutputStreamExt`][trait@crate::prelude::OutputStreamExt], [`trait@glib::ObjectExt`], [`PollableOutputStreamExtManual`][trait@crate::prelude::PollableOutputStreamExtManual], [`OutputStreamExtManual`][trait@crate::prelude::OutputStreamExtManual]
    #[doc(alias = "GPollableOutputStream")]
    pub struct PollableOutputStream(Interface<ffi::GPollableOutputStream, ffi::GPollableOutputStreamInterface>) @requires OutputStream;

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

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

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

/// Trait containing all [`struct@PollableOutputStream`] methods.
///
/// # Implementors
///
/// [`ConverterOutputStream`][struct@crate::ConverterOutputStream], [`MemoryOutputStream`][struct@crate::MemoryOutputStream], [`PollableOutputStream`][struct@crate::PollableOutputStream], [`UnixOutputStream`][struct@crate::UnixOutputStream]
pub trait PollableOutputStreamExt: IsA<PollableOutputStream> + sealed::Sealed + 'static {
    /// Checks if @self is actually pollable. Some classes may implement
    /// #GPollableOutputStream but have only certain instances of that
    /// class be pollable. If this method returns [`false`], then the behavior
    /// of other #GPollableOutputStream methods is undefined.
    ///
    /// For any given stream, the value returned by this method is constant;
    /// a stream cannot switch from pollable to non-pollable or vice versa.
    ///
    /// # Returns
    ///
    /// [`true`] if @self is pollable, [`false`] if not.
    #[doc(alias = "g_pollable_output_stream_can_poll")]
    fn can_poll(&self) -> bool {
        unsafe {
            from_glib(ffi::g_pollable_output_stream_can_poll(
                self.as_ref().to_glib_none().0,
            ))
        }
    }

    /// Checks if @self can be written.
    ///
    /// Note that some stream types may not be able to implement this 100%
    /// reliably, and it is possible that a call to g_output_stream_write()
    /// after this returns [`true`] would still block. To guarantee
    /// non-blocking behavior, you should always use
    /// g_pollable_output_stream_write_nonblocking(), which will return a
    /// [`IOErrorEnum::WouldBlock`][crate::IOErrorEnum::WouldBlock] error rather than blocking.
    ///
    /// The behaviour of this method is undefined if
    /// g_pollable_output_stream_can_poll() returns [`false`] for @self.
    ///
    /// # Returns
    ///
    /// [`true`] if @self is writable, [`false`] if not. If an error
    ///   has occurred on @self, this will result in
    ///   g_pollable_output_stream_is_writable() returning [`true`], and the
    ///   next attempt to write will return the error.
    #[doc(alias = "g_pollable_output_stream_is_writable")]
    fn is_writable(&self) -> bool {
        unsafe {
            from_glib(ffi::g_pollable_output_stream_is_writable(
                self.as_ref().to_glib_none().0,
            ))
        }
    }

    /// Attempts to write up to @count bytes from @buffer to @self, as
    /// with g_output_stream_write(). If @self is not currently writable,
    /// this will immediately return [`IOErrorEnum::WouldBlock`][crate::IOErrorEnum::WouldBlock], and you can
    /// use g_pollable_output_stream_create_source() to create a #GSource
    /// that will be triggered when @self is writable.
    ///
    /// Note that since this method never blocks, you cannot actually
    /// use @cancellable to cancel it. However, it will return an error
    /// if @cancellable has already been cancelled when you call, which
    /// may happen if you call this method after a source triggers due
    /// to having been cancelled.
    ///
    /// Also note that if [`IOErrorEnum::WouldBlock`][crate::IOErrorEnum::WouldBlock] is returned some underlying
    /// transports like D/TLS require that you re-send the same @buffer and
    /// @count in the next write call.
    ///
    /// The behaviour of this method is undefined if
    /// g_pollable_output_stream_can_poll() returns [`false`] for @self.
    /// ## `buffer`
    /// a buffer to write
    ///     data from
    /// ## `cancellable`
    /// a #GCancellable, or [`None`]
    ///
    /// # Returns
    ///
    /// the number of bytes written, or -1 on error (including
    ///   [`IOErrorEnum::WouldBlock`][crate::IOErrorEnum::WouldBlock]).
    #[doc(alias = "g_pollable_output_stream_write_nonblocking")]
    fn write_nonblocking(
        &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_pollable_output_stream_write_nonblocking(
                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))
            }
        }
    }
}

impl<O: IsA<PollableOutputStream>> PollableOutputStreamExt for O {}