Adding upstream version 110.0.1.upstream/110.0.1upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 263 insertions, 0 deletions

diff --git a/third_party/rust/memoffset-0.5.6/src/span_of.rs b/third_party/rust/memoffset-0.5.6/src/span_of.rs
new file mode 100644
index 0000000000..0592dbd11a
--- /dev/null
+++ b/third_party/rust/memoffset-0.5.6/src/span_of.rs
@@ -0,0 +1,263 @@
+// Copyright (c) 2017 Gilad Naaman
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in all
+// copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+// SOFTWARE.
+
+/// Reexport for `local_inner_macros`; see
+/// <https://doc.rust-lang.org/edition-guide/rust-2018/macros/macro-changes.html#macros-using-local_inner_macros>.
+#[doc(hidden)]
+#[macro_export]
+macro_rules! _memoffset__compile_error {
+    ($($inner:tt)*) => {
+        compile_error! { $($inner)* }
+    }
+}
+
+/// Produces a range instance representing the sub-slice containing the specified member.
+///
+/// This macro provides 2 forms of differing functionalities.
+///
+/// The first form is identical to the appearance of the `offset_of!` macro.
+///
+/// ```ignore
+/// span_of!(Struct, member)
+/// ```
+///
+/// The second form of `span_of!` returns a sub-slice which starts at one field, and ends at another.
+/// The general pattern of this form is:
+///
+/// ```ignore
+/// // Exclusive
+/// span_of!(Struct, member_a .. member_b)
+/// // Inclusive
+/// span_of!(Struct, member_a ..= member_b)
+///
+/// // Open-ended ranges
+/// span_of!(Struct, .. end)
+/// span_of!(Struct, start ..)
+/// ```
+///
+/// *Note*:
+/// This macro uses recursion in order to resolve the range expressions, so there is a limit to
+/// the complexity of the expression.
+/// In order to raise the limit, the compiler's recursion limit should be lifted.
+///
+/// ## Examples
+/// ```
+/// #[macro_use]
+/// extern crate memoffset;
+///
+/// #[repr(C)]
+/// struct Florp {
+///     a: u32
+/// }
+///
+/// #[repr(C)]
+/// struct Blarg {
+///     x: [u32; 2],
+///     y: [u8; 56],
+///     z: Florp,
+///     egg: [[u8; 4]; 4]
+/// }
+///
+/// fn main() {
+///     assert_eq!(0..84,  span_of!(Blarg, ..));
+///     assert_eq!(0..8,   span_of!(Blarg, .. y));
+///     assert_eq!(0..64,  span_of!(Blarg, ..= y));
+///     assert_eq!(0..8,   span_of!(Blarg, x));
+///     assert_eq!(8..84,  span_of!(Blarg, y ..));
+///     assert_eq!(0..8,   span_of!(Blarg, x .. y));
+///     assert_eq!(0..64,  span_of!(Blarg, x ..= y));
+/// }
+/// ```
+#[macro_export(local_inner_macros)]
+macro_rules! span_of {
+    (@helper  $root:ident, [] ..=) => {
+        _memoffset__compile_error!("Expected a range, found '..='")
+    };
+    (@helper $root:ident, [] ..) => {
+        _memoffset__compile_error!("Expected a range, found '..'")
+    };
+    // No explicit begin for range.
+    (@helper $root:ident, $parent:path, [] ..) => {{
+        // UB due to taking references to uninitialized fields for `size_of_val`.
+        ($root as usize,
+         $root as usize + $crate::mem::size_of_val(&(*$root)))
+    }};
+    (@helper $root:ident, $parent:path, [] ..= $field:tt) => {{
+        // UB due to taking references to uninitialized fields for `size_of_val`.
+        ($root as usize,
+         raw_field!($root, $parent, $field) as usize + $crate::mem::size_of_val(&(*$root).$field))
+    }};
+    (@helper $root:ident, $parent:path, [] .. $field:tt) => {{
+        ($root as usize, raw_field!($root, $parent, $field) as usize)
+    }};
+    // Explicit begin and end for range.
+    (@helper $root:ident, $parent:path, # $begin:tt [] ..= $end:tt) => {{
+        // UB due to taking references to uninitialized fields for `size_of_val`.
+        (raw_field!($root, $parent, $begin) as usize,
+         raw_field!($root, $parent, $end) as usize + $crate::mem::size_of_val(&(*$root).$end))
+    }};
+    (@helper $root:ident, $parent:path, # $begin:tt [] .. $end:tt) => {{
+        (raw_field!($root, $parent, $begin) as usize,
+         raw_field!($root, $parent, $end) as usize)
+    }};
+    // No explicit end for range.
+    (@helper $root:ident, $parent:path, # $begin:tt [] ..) => {{
+        // UB due to taking references to uninitialized fields for `size_of_val`.
+        (raw_field!($root, $parent, $begin) as usize,
+         $root as usize + $crate::mem::size_of_val(&*$root))
+    }};
+    (@helper $root:ident, $parent:path, # $begin:tt [] ..=) => {{
+        _memoffset__compile_error!(
+            "Found inclusive range to the end of a struct. Did you mean '..' instead of '..='?")
+    }};
+    // Just one field.
+    (@helper $root:ident, $parent:path, # $begin:tt []) => {{
+        // UB due to taking references to uninitialized fields for `size_of_val`.
+        (raw_field!($root, $parent, $begin) as usize,
+         raw_field!($root, $parent, $begin) as usize + $crate::mem::size_of_val(&(*$root).$begin))
+    }};
+    // Parsing.
+    (@helper $root:ident, $parent:path, $(# $begin:tt)+ [] $tt:tt $($rest:tt)*) => {{
+        span_of!(@helper $root, $parent, $(#$begin)* #$tt [] $($rest)*)
+    }};
+    (@helper $root:ident, $parent:path, [] $tt:tt $($rest:tt)*) => {{
+        span_of!(@helper $root, $parent, #$tt [] $($rest)*)
+    }};
+
+    // Entry point.
+    ($sty:path, $($exp:tt)+) => ({
+        unsafe {
+            // Get a base pointer.
+            _memoffset__let_base_ptr!(root, $sty);
+            let base = root as usize;
+            let (begin, end) = span_of!(@helper root, $sty, [] $($exp)*);
+            begin-base..end-base
+        }
+    });
+}
+
+#[cfg(test)]
+mod tests {
+    use core::mem;
+
+    #[test]
+    fn span_simple() {
+        #[repr(C)]
+        struct Foo {
+            a: u32,
+            b: [u8; 2],
+            c: i64,
+        }
+
+        assert_eq!(span_of!(Foo, a), 0..4);
+        assert_eq!(span_of!(Foo, b), 4..6);
+        assert_eq!(span_of!(Foo, c), 8..8 + 8);
+    }
+
+    #[test]
+    #[cfg_attr(miri, ignore)] // this creates unaligned references
+    fn span_simple_packed() {
+        #[repr(C, packed)]
+        struct Foo {
+            a: u32,
+            b: [u8; 2],
+            c: i64,
+        }
+
+        assert_eq!(span_of!(Foo, a), 0..4);
+        assert_eq!(span_of!(Foo, b), 4..6);
+        assert_eq!(span_of!(Foo, c), 6..6 + 8);
+    }
+
+    #[test]
+    fn span_forms() {
+        #[repr(C)]
+        struct Florp {
+            a: u32,
+        }
+
+        #[repr(C)]
+        struct Blarg {
+            x: u64,
+            y: [u8; 56],
+            z: Florp,
+            egg: [[u8; 4]; 5],
+        }
+
+        // Love me some brute force
+        assert_eq!(0..8, span_of!(Blarg, x));
+        assert_eq!(64..68, span_of!(Blarg, z));
+        assert_eq!(68..mem::size_of::<Blarg>(), span_of!(Blarg, egg));
+
+        assert_eq!(8..64, span_of!(Blarg, y..z));
+        assert_eq!(0..64, span_of!(Blarg, x..=y));
+    }
+
+    #[test]
+    fn ig_test() {
+        #[repr(C)]
+        struct Member {
+            foo: u32,
+        }
+
+        #[repr(C)]
+        struct Test {
+            x: u64,
+            y: [u8; 56],
+            z: Member,
+            egg: [[u8; 4]; 4],
+        }
+
+        assert_eq!(span_of!(Test, ..x), 0..0);
+        assert_eq!(span_of!(Test, ..=x), 0..8);
+        assert_eq!(span_of!(Test, ..y), 0..8);
+        assert_eq!(span_of!(Test, ..=y), 0..64);
+        assert_eq!(span_of!(Test, ..z), 0..64);
+        assert_eq!(span_of!(Test, ..=z), 0..68);
+        assert_eq!(span_of!(Test, ..egg), 0..68);
+        assert_eq!(span_of!(Test, ..=egg), 0..84);
+        assert_eq!(span_of!(Test, ..), 0..mem::size_of::<Test>());
+        assert_eq!(
+            span_of!(Test, x..),
+            offset_of!(Test, x)..mem::size_of::<Test>()
+        );
+        assert_eq!(
+            span_of!(Test, y..),
+            offset_of!(Test, y)..mem::size_of::<Test>()
+        );
+
+        assert_eq!(
+            span_of!(Test, z..),
+            offset_of!(Test, z)..mem::size_of::<Test>()
+        );
+        assert_eq!(
+            span_of!(Test, egg..),
+            offset_of!(Test, egg)..mem::size_of::<Test>()
+        );
+        assert_eq!(
+            span_of!(Test, x..y),
+            offset_of!(Test, x)..offset_of!(Test, y)
+        );
+        assert_eq!(
+            span_of!(Test, x..=y),
+            offset_of!(Test, x)..offset_of!(Test, y) + mem::size_of::<[u8; 56]>()
+        );
+    }
+}