1 files changed, 68 insertions, 0 deletions
diff --git a/third_party/rust/iovec/src/sys/windows.rs b/third_party/rust/iovec/src/sys/windows.rs
new file mode 100644
index 0000000000..fc5b8fb427
--- /dev/null
+++ b/third_party/rust/iovec/src/sys/windows.rs
@@ -0,0 +1,68 @@
+use std::{mem, slice, u32};
+
+// declare the types we need directly here to avoid bringing
+// in the old and slow winapi 0.2 dependency.
+
+type DWORD = u32;
+type ULONG = u32;
+type CHAR = i8;
+
+#[repr(C)]
+struct WSABUF {
+    pub len: ULONG,
+    pub buf: *mut CHAR,
+}
+
+pub struct IoVec {
+    inner: [u8],
+}
+
+pub const MAX_LENGTH: usize = u32::MAX as usize;
+
+impl IoVec {
+    pub fn as_ref(&self) -> &[u8] {
+        unsafe {
+            let vec = self.wsabuf();
+            slice::from_raw_parts(vec.buf as *const u8, vec.len as usize)
+        }
+    }
+
+    pub fn as_mut(&mut self) -> &mut [u8] {
+        unsafe {
+            let vec = self.wsabuf();
+            slice::from_raw_parts_mut(vec.buf as *mut u8, vec.len as usize)
+        }
+    }
+
+    unsafe fn wsabuf(&self) -> WSABUF {
+        mem::transmute(&self.inner)
+    }
+}
+
+impl<'a> From<&'a [u8]> for &'a IoVec {
+    fn from(src: &'a [u8]) -> Self {
+        assert!(src.len() > 0);
+        assert!(src.len() <= MAX_LENGTH);
+
+        unsafe {
+            mem::transmute(WSABUF {
+                buf: src.as_ptr() as *mut _,
+                len: src.len() as DWORD,
+            })
+        }
+    }
+}
+
+impl<'a> From<&'a mut [u8]> for &'a mut IoVec {
+    fn from(src: &'a mut [u8]) -> Self {
+        assert!(src.len() > 0);
+        assert!(src.len() <= MAX_LENGTH);
+
+        unsafe {
+            mem::transmute(WSABUF {
+                buf: src.as_ptr() as *mut _,
+                len: src.len() as DWORD,
+            })
+        }
+    }
+}