feat: impl std::io::Write for SliceDeque<u8>

Cargo.toml

@@ -34,6 +34,8 @@ default-features = false
 [features]
 default = [ "use_std" ]
 
+unstable = []
+
 # Enables features that require the standard library
 use_std = [ "libc/use_std" ]
 # Enables support for the bytes_buf trait. That is,

src/lib.rs

@@ -165,7 +165,7 @@ extern crate bytes;
 mod mirrored;
 pub use mirrored::{AllocError, Buffer};
 
-#[cfg(all(feature = "bytes_buf", feature = "use_std"))]
+#[cfg(all(feature = "use_std"))]
 use std::io;
 
 use core::{cmp, convert, fmt, hash, iter, mem, ops, ptr, slice, str};
@@ -267,6 +267,38 @@ pub struct SliceDeque<T> {
     buf: Buffer<T>,
 }
 
+#[cfg(feature = "use_std")]
+impl io::Write for SliceDeque<u8> {
+    #[inline]
+    fn write(&mut self, buf: &[u8]) -> io::Result<usize> {
+        self.extend_from_slice(buf);
+        Ok(buf.len())
+    }
+
+    #[inline]
+    fn write_vectored(
+        &mut self, bufs: &[io::IoSlice<'_>],
+    ) -> io::Result<usize> {
+        let len = bufs.iter().map(|b| b.len()).sum();
+        self.reserve(len);
+        for buf in bufs {
+            self.extend_from_slice(buf);
+        }
+        Ok(len)
+    }
+
+    #[inline]
+    fn write_all(&mut self, buf: &[u8]) -> io::Result<()> {
+        self.extend_from_slice(buf);
+        Ok(())
+    }
+
+    #[inline]
+    fn flush(&mut self) -> io::Result<()> {
+        Ok(())
+    }
+}
+
 // Safe because it is possible to free this from a different thread
 unsafe impl<T> Send for SliceDeque<T> where T: Send {}
 // Safe because this doesn't use any kind of interior mutability.