1 files changed, 156 insertions, 0 deletions
diff --git a/third_party/rust/httparse/src/iter.rs b/third_party/rust/httparse/src/iter.rs
new file mode 100644
index 0000000000..ca2767a1df
--- /dev/null
+++ b/third_party/rust/httparse/src/iter.rs
@@ -0,0 +1,156 @@
+use core::slice;
+
+pub struct Bytes<'a> {
+    slice: &'a [u8],
+    pos: usize
+}
+
+impl<'a> Bytes<'a> {
+    #[inline]
+    pub fn new(slice: &'a [u8]) -> Bytes<'a> {
+        Bytes {
+            slice: slice,
+            pos: 0
+        }
+    }
+
+    #[inline]
+    pub fn pos(&self) -> usize {
+        self.pos
+    }
+
+    #[inline]
+    pub fn peek(&self) -> Option<u8> {
+        self.slice.get(self.pos).cloned()
+    }
+
+    #[inline]
+    pub unsafe fn bump(&mut self) {
+        debug_assert!(self.pos + 1 <= self.slice.len(), "overflow");
+        self.pos += 1;
+    }
+
+    #[allow(unused)]
+    #[inline]
+    pub unsafe fn advance(&mut self, n: usize) {
+        debug_assert!(self.pos + n <= self.slice.len(), "overflow");
+        self.pos += n;
+    }
+
+    #[inline]
+    pub fn len(&self) -> usize {
+        self.slice.len()
+    }
+
+    #[inline]
+    pub fn slice(&mut self) -> &'a [u8] {
+        // not moving position at all, so it's safe
+        unsafe {
+            self.slice_skip(0)
+        }
+    }
+
+    #[inline]
+    pub unsafe fn slice_skip(&mut self, skip: usize) -> &'a [u8] {
+        debug_assert!(self.pos >= skip);
+        let head_pos = self.pos - skip;
+        let ptr = self.slice.as_ptr();
+        let head = slice::from_raw_parts(ptr, head_pos);
+        let tail = slice::from_raw_parts(ptr.offset(self.pos as isize), self.slice.len() - self.pos);
+        self.pos = 0;
+        self.slice = tail;
+        head
+    }
+
+    #[inline]
+    pub fn next_8<'b>(&'b mut self) -> Option<Bytes8<'b, 'a>> {
+        if self.slice.len() > self.pos + 8 {
+            Some(Bytes8::new(self))
+        } else {
+            None
+        }
+    }
+}
+
+impl<'a> AsRef<[u8]> for Bytes<'a> {
+    #[inline]
+    fn as_ref(&self) -> &[u8] {
+        &self.slice[self.pos..]
+    }
+}
+
+impl<'a> Iterator for Bytes<'a> {
+    type Item = u8;
+
+    #[inline]
+    fn next(&mut self) -> Option<u8> {
+        if self.slice.len() > self.pos {
+            let b = unsafe { *self.slice.get_unchecked(self.pos) };
+            self.pos += 1;
+            Some(b)
+        } else {
+            None
+        }
+    }
+}
+
+pub struct Bytes8<'a, 'b: 'a> {
+    bytes: &'a mut Bytes<'b>,
+    #[cfg(debug_assertions)]
+    pos: usize
+}
+
+macro_rules! bytes8_methods {
+    ($f:ident, $pos:expr) => {
+        #[inline]
+        pub fn $f(&mut self) -> u8 {
+            self.assert_pos($pos);
+            let b = unsafe { *self.bytes.slice.get_unchecked(self.bytes.pos) };
+            self.bytes.pos += 1;
+            b
+        }
+    };
+    () => {
+        bytes8_methods!(_0, 0);
+        bytes8_methods!(_1, 1);
+        bytes8_methods!(_2, 2);
+        bytes8_methods!(_3, 3);
+        bytes8_methods!(_4, 4);
+        bytes8_methods!(_5, 5);
+        bytes8_methods!(_6, 6);
+        bytes8_methods!(_7, 7);
+    }
+}
+
+impl<'a, 'b: 'a> Bytes8<'a, 'b> {
+    bytes8_methods! {}
+
+    #[cfg(not(debug_assertions))]
+    #[inline]
+    fn new(bytes: &'a mut Bytes<'b>) -> Bytes8<'a, 'b> {
+        Bytes8 {
+            bytes: bytes,
+        }
+    }
+
+    #[cfg(debug_assertions)]
+    #[inline]
+    fn new(bytes: &'a mut Bytes<'b>) -> Bytes8<'a, 'b> {
+        Bytes8 {
+            bytes: bytes,
+            pos: 0,
+        }
+    }
+
+    #[cfg(not(debug_assertions))]
+    #[inline]
+    fn assert_pos(&mut self, _pos: usize) {
+    }
+
+    #[cfg(debug_assertions)]
+    #[inline]
+    fn assert_pos(&mut self, pos: usize) {
+        assert!(self.pos == pos);
+        self.pos += 1;
+    }
+}