From 43a1bbb57814046cb222be06aaae2eb5a00f7a67 Mon Sep 17 00:00:00 2001
From: Victorien Elvinger <victorien@elvinger.fr>
Date: Tue, 16 Sep 2025 09:59:43 +0200
Subject: [PATCH] [io] Add specialized read_exact and write_all for slices

---
 embedded-io-async/src/impls/slice_mut.rs |  9 +++++++++
 embedded-io-async/src/impls/slice_ref.rs | 11 +++++++++++
 embedded-io-async/src/impls/vec.rs       |  6 ++++++
 embedded-io/src/impls/slice_mut.rs       |  9 +++++++++
 embedded-io/src/impls/slice_ref.rs       |  9 +++++++++
 embedded-io/src/impls/vec.rs             |  6 ++++++
 6 files changed, 50 insertions(+)

diff --git a/embedded-io-async/src/impls/slice_mut.rs b/embedded-io-async/src/impls/slice_mut.rs
index bd64d1320..fbbed187d 100644
--- a/embedded-io-async/src/impls/slice_mut.rs
+++ b/embedded-io-async/src/impls/slice_mut.rs
@@ -24,4 +24,13 @@ impl Write for &mut [u8] {
         *self = b;
         Ok(amt)
     }
+
+    #[inline]
+    async fn write_all(&mut self, buf: &[u8]) -> Result<(), Self::Error> {
+        if self.len() < buf.len() {
+            return Err(SliceWriteError::Full);
+        }
+        self.write(buf).await?;
+        Ok(())
+    }
 }
diff --git a/embedded-io-async/src/impls/slice_ref.rs b/embedded-io-async/src/impls/slice_ref.rs
index a6a4ba807..f49abbd62 100644
--- a/embedded-io-async/src/impls/slice_ref.rs
+++ b/embedded-io-async/src/impls/slice_ref.rs
@@ -22,6 +22,17 @@ impl Read for &[u8] {
         *self = b;
         Ok(amt)
     }
+
+    async fn read_exact(
+        &mut self,
+        buf: &mut [u8],
+    ) -> Result<(), embedded_io::ReadExactError<Self::Error>> {
+        if self.len() < buf.len() {
+            return Err(crate::ReadExactError::UnexpectedEof);
+        }
+        self.read(buf).await?;
+        Ok(())
+    }
 }
 
 impl BufRead for &[u8] {
diff --git a/embedded-io-async/src/impls/vec.rs b/embedded-io-async/src/impls/vec.rs
index c24405e39..a9741f1e0 100644
--- a/embedded-io-async/src/impls/vec.rs
+++ b/embedded-io-async/src/impls/vec.rs
@@ -9,4 +9,10 @@ impl Write for Vec<u8> {
         self.extend_from_slice(buf);
         Ok(buf.len())
     }
+
+    #[inline]
+    async fn write_all(&mut self, buf: &[u8]) -> Result<(), Self::Error> {
+        self.write(buf).await?;
+        Ok(())
+    }
 }
diff --git a/embedded-io/src/impls/slice_mut.rs b/embedded-io/src/impls/slice_mut.rs
index cee991ea6..86390652a 100644
--- a/embedded-io/src/impls/slice_mut.rs
+++ b/embedded-io/src/impls/slice_mut.rs
@@ -42,6 +42,15 @@ impl Write for &mut [u8] {
         Ok(amt)
     }
 
+    #[inline]
+    fn write_all(&mut self, buf: &[u8]) -> Result<(), Self::Error> {
+        if self.len() < buf.len() {
+            return Err(SliceWriteError::Full);
+        }
+        self.write(buf)?;
+        Ok(())
+    }
+
     #[inline]
     fn flush(&mut self) -> Result<(), Self::Error> {
         Ok(())
diff --git a/embedded-io/src/impls/slice_ref.rs b/embedded-io/src/impls/slice_ref.rs
index 0270aca27..af928f9a8 100644
--- a/embedded-io/src/impls/slice_ref.rs
+++ b/embedded-io/src/impls/slice_ref.rs
@@ -26,6 +26,15 @@ impl Read for &[u8] {
         *self = b;
         Ok(amt)
     }
+
+    #[inline]
+    fn read_exact(&mut self, buf: &mut [u8]) -> Result<(), crate::ReadExactError<Self::Error>> {
+        if self.len() < buf.len() {
+            return Err(crate::ReadExactError::UnexpectedEof);
+        }
+        self.read(buf)?;
+        Ok(())
+    }
 }
 
 impl BufRead for &[u8] {
diff --git a/embedded-io/src/impls/vec.rs b/embedded-io/src/impls/vec.rs
index 3b279c564..d8fbb638b 100644
--- a/embedded-io/src/impls/vec.rs
+++ b/embedded-io/src/impls/vec.rs
@@ -14,6 +14,12 @@ impl Write for Vec<u8> {
         Ok(buf.len())
     }
 
+    #[inline]
+    fn write_all(&mut self, buf: &[u8]) -> Result<(), Self::Error> {
+        self.write(buf)?;
+        Ok(())
+    }
+
     #[inline]
     fn flush(&mut self) -> Result<(), Self::Error> {
         Ok(())