Merge branch 'v0.4.x'

.travis.yml

@@ -42,6 +42,24 @@ matrix:
         - rustup target add wasm32-unknown-unknown
         - cargo build --target=wasm32-unknown-unknown
 
+    # Sanitizers
+    - rust: nightly
+      os: linux
+      script:
+        - |
+          set -e
+
+          export RUST_TEST_THREADS=1
+          export ASAN_OPTIONS="detect_odr_violation=0 detect_leaks=0"
+          export TSAN_OPTIONS="suppressions=`pwd`/ci/tsan"
+
+          # Run address sanitizer
+          RUSTFLAGS="-Z sanitizer=address" \
+          cargo test --tests --target x86_64-unknown-linux-gnu
+
+          # Run thread sanitizer
+          RUSTFLAGS="-Z sanitizer=thread" \
+          cargo test --tests --target x86_64-unknown-linux-gnu
 
 before_install: set -e
 

CHANGELOG.md

@@ -1,5 +1,11 @@
 # 0.5.0 (unreleased)
 
+# 0.4.7 (April 27, 2018)
+
+* Make `Buf` and `BufMut` usable as trait objects (#186).
+* impl BorrowMut for BytesMut (#185).
+* Improve accessor performance (#195).
+
 # 0.4.6 (Janary 8, 2018)
 
 * Implement FromIterator for Bytes/BytesMut (#148).

ci/tsan

@@ -0,0 +1,17 @@
+# TSAN suppressions file for `bytes`
+
+# TSAN does not understand fences and `Arc::drop` is implemented using a fence.
+# This causes many false positives.
+race:Arc*drop
+race:arc*Weak*drop
+
+# `std` mpsc is not used in any Bytes code base. This race is triggered by some
+# rust runtime logic.
+race:std*mpsc_queue
+
+# Probably more fences in std.
+race:__call_tls_dtors
+
+# `is_inline` is explicitly called concurrently without synchronization. The
+# safety explanation can be found in a comment.
+race:Inner::is_inline

src/bytes.rs

@@ -930,6 +930,7 @@ impl FromIterator<u8> for BytesMut {
         let mut out = BytesMut::with_capacity(maybe_max.unwrap_or(min));
 
         for i in iter {
+            out.reserve(1);
             out.put(i);
         }
 
@@ -1350,6 +1351,32 @@ impl BytesMut {
         self.truncate(0);
     }
 
+    /// Resizes the buffer so that `len` is equal to `new_len`.
+    ///
+    /// If `new_len` is greater than `len`, the buffer is extended by the
+    /// difference with each additional byte set to `value`. If `new_len` is
+    /// less than `len`, the buffer is simply truncated.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use bytes::BytesMut;
+    ///
+    /// let mut buf = BytesMut::new();
+    ///
+    /// buf.resize(3, 0x1);
+    /// assert_eq!(&buf[..], &[0x1, 0x1, 0x1]);
+    ///
+    /// buf.resize(2, 0x2);
+    /// assert_eq!(&buf[..], &[0x1, 0x1]);
+    ///
+    /// buf.resize(4, 0x3);
+    /// assert_eq!(&buf[..], &[0x1, 0x1, 0x3, 0x3]);
+    /// ```
+    pub fn resize(&mut self, new_len: usize, value: u8) {
+        self.inner.resize(new_len, value);
+    }
+
     /// Sets the length of the buffer.
     ///
     /// This will explicitly set the size of the buffer without actually
@@ -1975,6 +2002,21 @@ impl Inner {
         }
     }
 
+    fn resize(&mut self, new_len: usize, value: u8) {
+        let len = self.len();
+        if new_len > len {
+            let additional = new_len - len;
+            self.reserve(additional);
+            unsafe {
+                let dst = self.as_raw()[len..].as_mut_ptr();
+                ptr::write_bytes(dst, value, additional);
+                self.set_len(new_len);
+            }
+        } else {
+            self.truncate(new_len);
+        }
+    }
+
     unsafe fn set_start(&mut self, start: usize) {
         // Setting the start to 0 is a no-op, so return early if this is the
         // case.

tests/test_bytes.rs

@@ -823,3 +823,24 @@ fn bytes_mut_unsplit_two_split_offs() {
     buf.unsplit(buf2);
     assert_eq!(b"aaaabbbbccccdddd", &buf[..]);
 }
+
+#[test]
+fn from_iter_no_size_hint() {
+    use std::iter;
+
+    let mut expect = vec![];
+
+    let actual: Bytes = iter::repeat(b'x')
+        .scan(100, |cnt, item| {
+            if *cnt >= 1 {
+                *cnt -= 1;
+                expect.push(item);
+                Some(item)
+            } else {
+                None
+            }
+        })
+        .collect();
+
+    assert_eq!(&actual[..], &expect[..]);
+}