更新libclamav库1.0.0版本

clamav/libclamav_rust/.cargo/vendor/num-traits/src/sign.rs

@@ -0,0 +1,224 @@
+use core::num::Wrapping;
+use core::ops::Neg;
+
+use float::FloatCore;
+use Num;
+
+/// Useful functions for signed numbers (i.e. numbers that can be negative).
+pub trait Signed: Sized + Num + Neg<Output = Self> {
+    /// Computes the absolute value.
+    ///
+    /// For `f32` and `f64`, `NaN` will be returned if the number is `NaN`.
+    ///
+    /// For signed integers, `::MIN` will be returned if the number is `::MIN`.
+    fn abs(&self) -> Self;
+
+    /// The positive difference of two numbers.
+    ///
+    /// Returns `zero` if the number is less than or equal to `other`, otherwise the difference
+    /// between `self` and `other` is returned.
+    fn abs_sub(&self, other: &Self) -> Self;
+
+    /// Returns the sign of the number.
+    ///
+    /// For `f32` and `f64`:
+    ///
+    /// * `1.0` if the number is positive, `+0.0` or `INFINITY`
+    /// * `-1.0` if the number is negative, `-0.0` or `NEG_INFINITY`
+    /// * `NaN` if the number is `NaN`
+    ///
+    /// For signed integers:
+    ///
+    /// * `0` if the number is zero
+    /// * `1` if the number is positive
+    /// * `-1` if the number is negative
+    fn signum(&self) -> Self;
+
+    /// Returns true if the number is positive and false if the number is zero or negative.
+    fn is_positive(&self) -> bool;
+
+    /// Returns true if the number is negative and false if the number is zero or positive.
+    fn is_negative(&self) -> bool;
+}
+
+macro_rules! signed_impl {
+    ($($t:ty)*) => ($(
+        impl Signed for $t {
+            #[inline]
+            fn abs(&self) -> $t {
+                if self.is_negative() { -*self } else { *self }
+            }
+
+            #[inline]
+            fn abs_sub(&self, other: &$t) -> $t {
+                if *self <= *other { 0 } else { *self - *other }
+            }
+
+            #[inline]
+            fn signum(&self) -> $t {
+                match *self {
+                    n if n > 0 => 1,
+                    0 => 0,
+                    _ => -1,
+                }
+            }
+
+            #[inline]
+            fn is_positive(&self) -> bool { *self > 0 }
+
+            #[inline]
+            fn is_negative(&self) -> bool { *self < 0 }
+        }
+    )*)
+}
+
+signed_impl!(isize i8 i16 i32 i64);
+
+#[cfg(has_i128)]
+signed_impl!(i128);
+
+impl<T: Signed> Signed for Wrapping<T>
+where
+    Wrapping<T>: Num + Neg<Output = Wrapping<T>>,
+{
+    #[inline]
+    fn abs(&self) -> Self {
+        Wrapping(self.0.abs())
+    }
+
+    #[inline]
+    fn abs_sub(&self, other: &Self) -> Self {
+        Wrapping(self.0.abs_sub(&other.0))
+    }
+
+    #[inline]
+    fn signum(&self) -> Self {
+        Wrapping(self.0.signum())
+    }
+
+    #[inline]
+    fn is_positive(&self) -> bool {
+        self.0.is_positive()
+    }
+
+    #[inline]
+    fn is_negative(&self) -> bool {
+        self.0.is_negative()
+    }
+}
+
+macro_rules! signed_float_impl {
+    ($t:ty) => {
+        impl Signed for $t {
+            /// Computes the absolute value. Returns `NAN` if the number is `NAN`.
+            #[inline]
+            fn abs(&self) -> $t {
+                FloatCore::abs(*self)
+            }
+
+            /// The positive difference of two numbers. Returns `0.0` if the number is
+            /// less than or equal to `other`, otherwise the difference between`self`
+            /// and `other` is returned.
+            #[inline]
+            fn abs_sub(&self, other: &$t) -> $t {
+                if *self <= *other {
+                    0.
+                } else {
+                    *self - *other
+                }
+            }
+
+            /// # Returns
+            ///
+            /// - `1.0` if the number is positive, `+0.0` or `INFINITY`
+            /// - `-1.0` if the number is negative, `-0.0` or `NEG_INFINITY`
+            /// - `NAN` if the number is NaN
+            #[inline]
+            fn signum(&self) -> $t {
+                FloatCore::signum(*self)
+            }
+
+            /// Returns `true` if the number is positive, including `+0.0` and `INFINITY`
+            #[inline]
+            fn is_positive(&self) -> bool {
+                FloatCore::is_sign_positive(*self)
+            }
+
+            /// Returns `true` if the number is negative, including `-0.0` and `NEG_INFINITY`
+            #[inline]
+            fn is_negative(&self) -> bool {
+                FloatCore::is_sign_negative(*self)
+            }
+        }
+    };
+}
+
+signed_float_impl!(f32);
+signed_float_impl!(f64);
+
+/// Computes the absolute value.
+///
+/// For `f32` and `f64`, `NaN` will be returned if the number is `NaN`
+///
+/// For signed integers, `::MIN` will be returned if the number is `::MIN`.
+#[inline(always)]
+pub fn abs<T: Signed>(value: T) -> T {
+    value.abs()
+}
+
+/// The positive difference of two numbers.
+///
+/// Returns zero if `x` is less than or equal to `y`, otherwise the difference
+/// between `x` and `y` is returned.
+#[inline(always)]
+pub fn abs_sub<T: Signed>(x: T, y: T) -> T {
+    x.abs_sub(&y)
+}
+
+/// Returns the sign of the number.
+///
+/// For `f32` and `f64`:
+///
+/// * `1.0` if the number is positive, `+0.0` or `INFINITY`
+/// * `-1.0` if the number is negative, `-0.0` or `NEG_INFINITY`
+/// * `NaN` if the number is `NaN`
+///
+/// For signed integers:
+///
+/// * `0` if the number is zero
+/// * `1` if the number is positive
+/// * `-1` if the number is negative
+#[inline(always)]
+pub fn signum<T: Signed>(value: T) -> T {
+    value.signum()
+}
+
+/// A trait for values which cannot be negative
+pub trait Unsigned: Num {}
+
+macro_rules! empty_trait_impl {
+    ($name:ident for $($t:ty)*) => ($(
+        impl $name for $t {}
+    )*)
+}
+
+empty_trait_impl!(Unsigned for usize u8 u16 u32 u64);
+#[cfg(has_i128)]
+empty_trait_impl!(Unsigned for u128);
+
+impl<T: Unsigned> Unsigned for Wrapping<T> where Wrapping<T>: Num {}
+
+#[test]
+fn unsigned_wrapping_is_unsigned() {
+    fn require_unsigned<T: Unsigned>(_: &T) {}
+    require_unsigned(&Wrapping(42_u32));
+}
+
+// Commenting this out since it doesn't compile on Rust 1.8,
+// because on this version Wrapping doesn't implement Neg and therefore can't
+// implement Signed.
+// #[test]
+// fn signed_wrapping_is_signed() {
+//     fn require_signed<T: Signed>(_: &T) {}
+//     require_signed(&Wrapping(-42));
+// }