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-rw-r--r--vendor/tokio/src/io/util/lines.rs143
1 files changed, 143 insertions, 0 deletions
diff --git a/vendor/tokio/src/io/util/lines.rs b/vendor/tokio/src/io/util/lines.rs
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index 000000000..d02a4538a
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+++ b/vendor/tokio/src/io/util/lines.rs
@@ -0,0 +1,143 @@
+use crate::io::util::read_line::read_line_internal;
+use crate::io::AsyncBufRead;
+
+use pin_project_lite::pin_project;
+use std::io;
+use std::mem;
+use std::pin::Pin;
+use std::task::{Context, Poll};
+
+pin_project! {
+ /// Read lines from an [`AsyncBufRead`].
+ ///
+ /// A `Lines` can be turned into a `Stream` with [`LinesStream`].
+ ///
+ /// This type is usually created using the [`lines`] method.
+ ///
+ /// [`AsyncBufRead`]: crate::io::AsyncBufRead
+ /// [`LinesStream`]: https://docs.rs/tokio-stream/0.1/tokio_stream/wrappers/struct.LinesStream.html
+ /// [`lines`]: crate::io::AsyncBufReadExt::lines
+ #[derive(Debug)]
+ #[must_use = "streams do nothing unless polled"]
+ #[cfg_attr(docsrs, doc(cfg(feature = "io-util")))]
+ pub struct Lines<R> {
+ #[pin]
+ reader: R,
+ buf: String,
+ bytes: Vec<u8>,
+ read: usize,
+ }
+}
+
+pub(crate) fn lines<R>(reader: R) -> Lines<R>
+where
+ R: AsyncBufRead,
+{
+ Lines {
+ reader,
+ buf: String::new(),
+ bytes: Vec::new(),
+ read: 0,
+ }
+}
+
+impl<R> Lines<R>
+where
+ R: AsyncBufRead + Unpin,
+{
+ /// Returns the next line in the stream.
+ ///
+ /// # Examples
+ ///
+ /// ```
+ /// # use tokio::io::AsyncBufRead;
+ /// use tokio::io::AsyncBufReadExt;
+ ///
+ /// # async fn dox(my_buf_read: impl AsyncBufRead + Unpin) -> std::io::Result<()> {
+ /// let mut lines = my_buf_read.lines();
+ ///
+ /// while let Some(line) = lines.next_line().await? {
+ /// println!("length = {}", line.len())
+ /// }
+ /// # Ok(())
+ /// # }
+ /// ```
+ pub async fn next_line(&mut self) -> io::Result<Option<String>> {
+ use crate::future::poll_fn;
+
+ poll_fn(|cx| Pin::new(&mut *self).poll_next_line(cx)).await
+ }
+
+ /// Obtain a mutable reference to the underlying reader
+ pub fn get_mut(&mut self) -> &mut R {
+ &mut self.reader
+ }
+
+ /// Obtain a reference to the underlying reader
+ pub fn get_ref(&mut self) -> &R {
+ &self.reader
+ }
+
+ /// Unwraps this `Lines<R>`, returning the underlying reader.
+ ///
+ /// Note that any leftover data in the internal buffer is lost.
+ /// Therefore, a following read from the underlying reader may lead to data loss.
+ pub fn into_inner(self) -> R {
+ self.reader
+ }
+}
+
+impl<R> Lines<R>
+where
+ R: AsyncBufRead,
+{
+ /// Polls for the next line in the stream.
+ ///
+ /// This method returns:
+ ///
+ /// * `Poll::Pending` if the next line is not yet available.
+ /// * `Poll::Ready(Ok(Some(line)))` if the next line is available.
+ /// * `Poll::Ready(Ok(None))` if there are no more lines in this stream.
+ /// * `Poll::Ready(Err(err))` if an IO error occurred while reading the next line.
+ ///
+ /// When the method returns `Poll::Pending`, the `Waker` in the provided
+ /// `Context` is scheduled to receive a wakeup when more bytes become
+ /// available on the underlying IO resource.
+ ///
+ /// Note that on multiple calls to `poll_next_line`, only the `Waker` from
+ /// the `Context` passed to the most recent call is scheduled to receive a
+ /// wakeup.
+ pub fn poll_next_line(
+ self: Pin<&mut Self>,
+ cx: &mut Context<'_>,
+ ) -> Poll<io::Result<Option<String>>> {
+ let me = self.project();
+
+ let n = ready!(read_line_internal(me.reader, cx, me.buf, me.bytes, me.read))?;
+ debug_assert_eq!(*me.read, 0);
+
+ if n == 0 && me.buf.is_empty() {
+ return Poll::Ready(Ok(None));
+ }
+
+ if me.buf.ends_with('\n') {
+ me.buf.pop();
+
+ if me.buf.ends_with('\r') {
+ me.buf.pop();
+ }
+ }
+
+ Poll::Ready(Ok(Some(mem::take(me.buf))))
+ }
+}
+
+#[cfg(test)]
+mod tests {
+ use super::*;
+
+ #[test]
+ fn assert_unpin() {
+ crate::is_unpin::<Lines<()>>();
+ }
+}