Import bytes-0.5.4

* Add OWNERS and Android.bp

Bug: 143953733
Test: make
Change-Id: Ica69d7252abb1c2967f2c0e11a62d0bd83192fb3

3 files changed, 554 insertions, 0 deletions

diff --git a/benches/buf.rs b/benches/buf.rs
new file mode 100644
index 0000000..0c9a1d9
--- /dev/null
+++ b/benches/buf.rs
@@ -0,0 +1,187 @@
+#![feature(test)]
+#![deny(warnings, rust_2018_idioms)]
+
+extern crate test;
+
+use test::Bencher;
+use bytes::Buf;
+
+/// Dummy Buf implementation
+struct TestBuf {
+    buf: &'static [u8],
+    readlens: &'static [usize],
+    init_pos: usize,
+    pos: usize,
+    readlen_pos: usize,
+    readlen: usize,
+}
+impl TestBuf {
+    fn new(buf: &'static [u8], readlens: &'static [usize], init_pos: usize) -> TestBuf {
+        let mut buf = TestBuf {
+            buf,
+            readlens,
+            init_pos,
+            pos: 0,
+            readlen_pos: 0,
+            readlen: 0,
+        };
+        buf.reset();
+        buf
+    }
+    fn reset(&mut self) {
+        self.pos = self.init_pos;
+        self.readlen_pos = 0;
+        self.next_readlen();
+    }
+    /// Compute the length of the next read :
+    /// - use the next value specified in readlens (capped by remaining) if any
+    /// - else the remaining
+    fn next_readlen(&mut self) {
+        self.readlen = self.buf.len() - self.pos;
+        if let Some(readlen) = self.readlens.get(self.readlen_pos) {
+            self.readlen = std::cmp::min(self.readlen, *readlen);
+            self.readlen_pos += 1;
+        }
+    }
+}
+impl Buf for TestBuf {
+    fn remaining(&self) -> usize {
+        return self.buf.len() - self.pos;
+    }
+    fn advance(&mut self, cnt: usize) {
+        self.pos += cnt;
+        assert!(self.pos <= self.buf.len());
+        self.next_readlen();
+    }
+    fn bytes(&self) -> &[u8] {
+        if self.readlen == 0 {
+            Default::default()
+        } else {
+            &self.buf[self.pos..self.pos + self.readlen]
+        }
+    }
+}
+
+/// Dummy Buf implementation
+///  version with methods forced to not be inlined (to simulate costly calls)
+struct TestBufC {
+    inner: TestBuf,
+}
+impl TestBufC {
+    fn new(buf: &'static [u8], readlens: &'static [usize], init_pos: usize) -> TestBufC {
+        TestBufC {
+            inner: TestBuf::new(buf, readlens, init_pos),
+        }
+    }
+    fn reset(&mut self) {
+        self.inner.reset()
+    }
+}
+impl Buf for TestBufC {
+    #[inline(never)]
+    fn remaining(&self) -> usize {
+        self.inner.remaining()
+    }
+    #[inline(never)]
+    fn advance(&mut self, cnt: usize) {
+        self.inner.advance(cnt)
+    }
+    #[inline(never)]
+    fn bytes(&self) -> &[u8] {
+        self.inner.bytes()
+    }
+}
+
+macro_rules! bench {
+    ($fname:ident, testbuf $testbuf:ident $readlens:expr, $method:ident $(,$arg:expr)*) => (
+        #[bench]
+        fn $fname(b: &mut Bencher) {
+            let mut bufs = [
+                $testbuf::new(&[1u8; 8+0], $readlens, 0),
+                $testbuf::new(&[1u8; 8+1], $readlens, 1),
+                $testbuf::new(&[1u8; 8+2], $readlens, 2),
+                $testbuf::new(&[1u8; 8+3], $readlens, 3),
+                $testbuf::new(&[1u8; 8+4], $readlens, 4),
+                $testbuf::new(&[1u8; 8+5], $readlens, 5),
+                $testbuf::new(&[1u8; 8+6], $readlens, 6),
+                $testbuf::new(&[1u8; 8+7], $readlens, 7),
+            ];
+            b.iter(|| {
+                for i in 0..8 {
+                    bufs[i].reset();
+                    let buf: &mut dyn Buf =  &mut bufs[i]; // type erasure
+                    test::black_box(buf.$method($($arg,)*));
+                }
+            })
+        }
+    );
+    ($fname:ident, slice, $method:ident $(,$arg:expr)*) => (
+        #[bench]
+        fn $fname(b: &mut Bencher) {
+            // buf must be long enough for one read of 8 bytes starting at pos 7
+            let arr = [1u8; 8+7];
+            b.iter(|| {
+                for i in 0..8 {
+                    let mut buf = &arr[i..];
+                    let buf = &mut buf as &mut dyn Buf; // type erasure
+                    test::black_box(buf.$method($($arg,)*));
+                }
+            })
+        }
+    );
+    ($fname:ident, option) => (
+        #[bench]
+        fn $fname(b: &mut Bencher) {
+            let data = [1u8; 1];
+            b.iter(|| {
+                for _ in 0..8 {
+                    let mut buf = Some(data);
+                    let buf = &mut buf as &mut dyn Buf; // type erasure
+                    test::black_box(buf.get_u8());
+                }
+            })
+        }
+    );
+}
+
+macro_rules! bench_group {
+    ($method:ident $(,$arg:expr)*) => (
+        bench!(slice, slice, $method $(,$arg)*);
+        bench!(tbuf_1,        testbuf TestBuf  &[],  $method $(,$arg)*);
+        bench!(tbuf_1_costly, testbuf TestBufC &[],  $method $(,$arg)*);
+        bench!(tbuf_2,        testbuf TestBuf  &[1], $method $(,$arg)*);
+        bench!(tbuf_2_costly, testbuf TestBufC &[1], $method $(,$arg)*);
+        // bench!(tbuf_onebyone,        testbuf TestBuf  &[1,1,1,1,1,1,1,1], $method $(,$arg)*);
+        // bench!(tbuf_onebyone_costly, testbuf TestBufC &[1,1,1,1,1,1,1,1], $method $(,$arg)*);
+    );
+}
+
+mod get_u8 {
+    use super::*;
+    bench_group!(get_u8);
+    bench!(option, option);
+}
+mod get_u16 {
+    use super::*;
+    bench_group!(get_u16);
+}
+mod get_u32 {
+    use super::*;
+    bench_group!(get_u32);
+}
+mod get_u64 {
+    use super::*;
+    bench_group!(get_u64);
+}
+mod get_f32 {
+    use super::*;
+    bench_group!(get_f32);
+}
+mod get_f64 {
+    use super::*;
+    bench_group!(get_f64);
+}
+mod get_uint24 {
+    use super::*;
+    bench_group!(get_uint, 3);
+}
diff --git a/benches/bytes.rs b/benches/bytes.rs
new file mode 100644
index 0000000..9c36e60
--- /dev/null
+++ b/benches/bytes.rs
@@ -0,0 +1,118 @@
+#![feature(test)]
+#![deny(warnings, rust_2018_idioms)]
+
+extern crate test;
+
+use test::Bencher;
+use bytes::Bytes;
+
+#[bench]
+fn deref_unique(b: &mut Bencher) {
+    let buf = Bytes::from(vec![0; 1024]);
+
+    b.iter(|| {
+        for _ in 0..1024 {
+            test::black_box(&buf[..]);
+        }
+    })
+}
+
+#[bench]
+fn deref_shared(b: &mut Bencher) {
+    let buf = Bytes::from(vec![0; 1024]);
+    let _b2 = buf.clone();
+
+    b.iter(|| {
+        for _ in 0..1024 {
+            test::black_box(&buf[..]);
+        }
+    })
+}
+
+#[bench]
+fn deref_static(b: &mut Bencher) {
+    let buf = Bytes::from_static(b"hello world");
+
+    b.iter(|| {
+        for _ in 0..1024 {
+            test::black_box(&buf[..]);
+        }
+    })
+}
+
+#[bench]
+fn clone_static(b: &mut Bencher) {
+    let bytes = Bytes::from_static("hello world 1234567890 and have a good byte 0987654321".as_bytes());
+
+    b.iter(|| {
+        for _ in 0..1024 {
+            test::black_box(&bytes.clone());
+        }
+    })
+}
+
+#[bench]
+fn clone_shared(b: &mut Bencher) {
+    let bytes = Bytes::from(b"hello world 1234567890 and have a good byte 0987654321".to_vec());
+
+    b.iter(|| {
+        for _ in 0..1024 {
+            test::black_box(&bytes.clone());
+        }
+    })
+}
+
+#[bench]
+fn clone_arc_vec(b: &mut Bencher) {
+    use std::sync::Arc;
+    let bytes = Arc::new(b"hello world 1234567890 and have a good byte 0987654321".to_vec());
+
+    b.iter(|| {
+        for _ in 0..1024 {
+            test::black_box(&bytes.clone());
+        }
+    })
+}
+
+#[bench]
+fn from_long_slice(b: &mut Bencher) {
+    let data = [0u8; 128];
+    b.bytes = data.len() as u64;
+    b.iter(|| {
+        let buf = Bytes::copy_from_slice(&data[..]);
+        test::black_box(buf);
+    })
+}
+
+#[bench]
+fn slice_empty(b: &mut Bencher) {
+    b.iter(|| {
+        let b = Bytes::from(vec![17; 1024]).clone();
+        for i in 0..1000 {
+            test::black_box(b.slice(i % 100..i % 100));
+        }
+    })
+}
+
+#[bench]
+fn slice_short_from_arc(b: &mut Bencher) {
+    b.iter(|| {
+        // `clone` is to convert to ARC
+        let b = Bytes::from(vec![17; 1024]).clone();
+        for i in 0..1000 {
+            test::black_box(b.slice(1..2 + i % 10));
+        }
+    })
+}
+
+#[bench]
+fn split_off_and_drop(b: &mut Bencher) {
+    b.iter(|| {
+        for _ in 0..1024 {
+            let v = vec![10; 200];
+            let mut b = Bytes::from(v);
+            test::black_box(b.split_off(100));
+            test::black_box(b);
+        }
+    })
+}
diff --git a/benches/bytes_mut.rs b/benches/bytes_mut.rs
new file mode 100644
index 0000000..ded1d14
--- /dev/null
+++ b/benches/bytes_mut.rs
@@ -0,0 +1,249 @@
+#![feature(test)]
+#![deny(warnings, rust_2018_idioms)]
+
+extern crate test;
+
+use test::Bencher;
+use bytes::{BufMut, BytesMut};
+
+#[bench]
+fn alloc_small(b: &mut Bencher) {
+    b.iter(|| {
+        for _ in 0..1024 {
+            test::black_box(BytesMut::with_capacity(12));
+        }
+    })
+}
+
+#[bench]
+fn alloc_mid(b: &mut Bencher) {
+    b.iter(|| {
+        test::black_box(BytesMut::with_capacity(128));
+    })
+}
+
+#[bench]
+fn alloc_big(b: &mut Bencher) {
+    b.iter(|| {
+        test::black_box(BytesMut::with_capacity(4096));
+    })
+}
+
+
+#[bench]
+fn deref_unique(b: &mut Bencher) {
+    let mut buf = BytesMut::with_capacity(4096);
+    buf.put(&[0u8; 1024][..]);
+
+    b.iter(|| {
+        for _ in 0..1024 {
+            test::black_box(&buf[..]);
+        }
+    })
+}
+
+#[bench]
+fn deref_unique_unroll(b: &mut Bencher) {
+    let mut buf = BytesMut::with_capacity(4096);
+    buf.put(&[0u8; 1024][..]);
+
+    b.iter(|| {
+        for _ in 0..128 {
+            test::black_box(&buf[..]);
+            test::black_box(&buf[..]);
+            test::black_box(&buf[..]);
+            test::black_box(&buf[..]);
+            test::black_box(&buf[..]);
+            test::black_box(&buf[..]);
+            test::black_box(&buf[..]);
+            test::black_box(&buf[..]);
+        }
+    })
+}
+
+#[bench]
+fn deref_shared(b: &mut Bencher) {
+    let mut buf = BytesMut::with_capacity(4096);
+    buf.put(&[0u8; 1024][..]);
+    let _b2 = buf.split_off(1024);
+
+    b.iter(|| {
+        for _ in 0..1024 {
+            test::black_box(&buf[..]);
+        }
+    })
+}
+
+#[bench]
+fn deref_two(b: &mut Bencher) {
+    let mut buf1 = BytesMut::with_capacity(8);
+    buf1.put(&[0u8; 8][..]);
+
+    let mut buf2 = BytesMut::with_capacity(4096);
+    buf2.put(&[0u8; 1024][..]);
+
+    b.iter(|| {
+        for _ in 0..512 {
+            test::black_box(&buf1[..]);
+            test::black_box(&buf2[..]);
+        }
+    })
+}
+
+#[bench]
+fn clone_frozen(b: &mut Bencher) {
+    let bytes = BytesMut::from(&b"hello world 1234567890 and have a good byte 0987654321"[..]).split().freeze();
+
+    b.iter(|| {
+        for _ in 0..1024 {
+            test::black_box(&bytes.clone());
+        }
+    })
+}
+
+#[bench]
+fn alloc_write_split_to_mid(b: &mut Bencher) {
+    b.iter(|| {
+        let mut buf = BytesMut::with_capacity(128);
+        buf.put_slice(&[0u8; 64]);
+        test::black_box(buf.split_to(64));
+    })
+}
+
+#[bench]
+fn drain_write_drain(b: &mut Bencher) {
+    let data = [0u8; 128];
+
+    b.iter(|| {
+        let mut buf = BytesMut::with_capacity(1024);
+        let mut parts = Vec::with_capacity(8);
+
+        for _ in 0..8 {
+            buf.put(&data[..]);
+            parts.push(buf.split_to(128));
+        }
+
+        test::black_box(parts);
+    })
+}
+
+#[bench]
+fn fmt_write(b: &mut Bencher) {
+    use std::fmt::Write;
+    let mut buf = BytesMut::with_capacity(128);
+    let s = "foo bar baz quux lorem ipsum dolor et";
+
+    b.bytes = s.len() as u64;
+    b.iter(|| {
+        let _ = write!(buf, "{}", s);
+        test::black_box(&buf);
+        unsafe { buf.set_len(0); }
+    })
+}
+
+#[bench]
+fn bytes_mut_extend(b: &mut Bencher) {
+    let mut buf = BytesMut::with_capacity(256);
+    let data = [33u8; 32];
+
+    b.bytes = data.len() as u64 * 4;
+    b.iter(|| {
+        for _ in 0..4 {
+            buf.extend(&data);
+        }
+        test::black_box(&buf);
+        unsafe { buf.set_len(0); }
+    });
+}
+
+// BufMut for BytesMut vs Vec<u8>
+
+#[bench]
+fn put_slice_bytes_mut(b: &mut Bencher) {
+    let mut buf = BytesMut::with_capacity(256);
+    let data = [33u8; 32];
+
+    b.bytes = data.len() as u64 * 4;
+    b.iter(|| {
+        for _ in 0..4 {
+            buf.put_slice(&data);
+        }
+        test::black_box(&buf);
+        unsafe { buf.set_len(0); }
+    });
+}
+
+#[bench]
+fn put_u8_bytes_mut(b: &mut Bencher) {
+    let mut buf = BytesMut::with_capacity(256);
+    let cnt = 128;
+
+    b.bytes = cnt as u64;
+    b.iter(|| {
+        for _ in 0..cnt {
+            buf.put_u8(b'x');
+        }
+        test::black_box(&buf);
+        unsafe { buf.set_len(0); }
+    });
+}
+
+#[bench]
+fn put_slice_vec(b: &mut Bencher) {
+    let mut buf = Vec::<u8>::with_capacity(256);
+    let data = [33u8; 32];
+
+    b.bytes = data.len() as u64 * 4;
+    b.iter(|| {
+        for _ in 0..4 {
+            buf.put_slice(&data);
+        }
+        test::black_box(&buf);
+        unsafe { buf.set_len(0); }
+    });
+}
+
+#[bench]
+fn put_u8_vec(b: &mut Bencher) {
+    let mut buf = Vec::<u8>::with_capacity(256);
+    let cnt = 128;
+
+    b.bytes = cnt as u64;
+    b.iter(|| {
+        for _ in 0..cnt {
+            buf.put_u8(b'x');
+        }
+        test::black_box(&buf);
+        unsafe { buf.set_len(0); }
+    });
+}
+
+#[bench]
+fn put_slice_vec_extend(b: &mut Bencher) {
+    let mut buf = Vec::<u8>::with_capacity(256);
+    let data = [33u8; 32];
+
+    b.bytes = data.len() as u64 * 4;
+    b.iter(|| {
+        for _ in 0..4 {
+            buf.extend_from_slice(&data);
+        }
+        test::black_box(&buf);
+        unsafe { buf.set_len(0); }
+    });
+}
+
+#[bench]
+fn put_u8_vec_push(b: &mut Bencher) {
+    let mut buf = Vec::<u8>::with_capacity(256);
+    let cnt = 128;
+
+    b.bytes = cnt as u64;
+    b.iter(|| {
+        for _ in 0..cnt {
+            buf.push(b'x');
+        }
+        test::black_box(&buf);
+        unsafe { buf.set_len(0); }
+    });
+}