| // Copyright 2014 The Rust Project Developers. See the COPYRIGHT |
| // file at the top-level directory of this distribution and at |
| // http://rust-lang.org/COPYRIGHT. |
| // |
| // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or |
| // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license |
| // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your |
| // option. This file may not be copied, modified, or distributed |
| // except according to those terms. |
| |
| |
| // Do not remove on snapshot creation. Needed for bootstrap. (Issue #22364) |
| #![cfg_attr(stage0, feature(custom_attribute))] |
| #![crate_name = "rustc_bitflags"] |
| #![feature(associated_consts)] |
| #![feature(staged_api)] |
| #![staged_api] |
| #![crate_type = "rlib"] |
| #![feature(no_std)] |
| #![no_std] |
| #![unstable(feature = "rustc_private", issue = "27812")] |
| |
| //! A typesafe bitmask flag generator. |
| |
| #[cfg(test)] #[macro_use] extern crate std; |
| |
| /// The `bitflags!` macro generates a `struct` that holds a set of C-style |
| /// bitmask flags. It is useful for creating typesafe wrappers for C APIs. |
| /// |
| /// The flags should only be defined for integer types, otherwise unexpected |
| /// type errors may occur at compile time. |
| /// |
| /// # Examples |
| /// |
| /// ```{.rust} |
| /// #![feature(rustc_private)] |
| /// #![feature(associated_consts)] |
| /// #[macro_use] extern crate rustc_bitflags; |
| /// |
| /// bitflags! { |
| /// flags Flags: u32 { |
| /// const FLAG_A = 0b00000001, |
| /// const FLAG_B = 0b00000010, |
| /// const FLAG_C = 0b00000100, |
| /// const FLAG_ABC = Flags::FLAG_A.bits |
| /// | Flags::FLAG_B.bits |
| /// | Flags::FLAG_C.bits, |
| /// } |
| /// } |
| /// |
| /// fn main() { |
| /// let e1 = Flags::FLAG_A | Flags::FLAG_C; |
| /// let e2 = Flags::FLAG_B | Flags::FLAG_C; |
| /// assert!((e1 | e2) == Flags::FLAG_ABC); // union |
| /// assert!((e1 & e2) == Flags::FLAG_C); // intersection |
| /// assert!((e1 - e2) == Flags::FLAG_A); // set difference |
| /// assert!(!e2 == Flags::FLAG_A); // set complement |
| /// } |
| /// ``` |
| /// |
| /// The generated `struct`s can also be extended with type and trait implementations: |
| /// |
| /// ```{.rust} |
| /// #![feature(rustc_private)] |
| /// #[macro_use] extern crate rustc_bitflags; |
| /// |
| /// use std::fmt; |
| /// |
| /// bitflags! { |
| /// flags Flags: u32 { |
| /// const FLAG_A = 0b00000001, |
| /// const FLAG_B = 0b00000010, |
| /// } |
| /// } |
| /// |
| /// impl Flags { |
| /// pub fn clear(&mut self) { |
| /// self.bits = 0; // The `bits` field can be accessed from within the |
| /// // same module where the `bitflags!` macro was invoked. |
| /// } |
| /// } |
| /// |
| /// impl fmt::Debug for Flags { |
| /// fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { |
| /// write!(f, "hi!") |
| /// } |
| /// } |
| /// |
| /// fn main() { |
| /// let mut flags = Flags::FLAG_A | Flags::FLAG_B; |
| /// flags.clear(); |
| /// assert!(flags.is_empty()); |
| /// assert_eq!(format!("{:?}", flags), "hi!"); |
| /// } |
| /// ``` |
| /// |
| /// # Attributes |
| /// |
| /// Attributes can be attached to the generated `struct` by placing them |
| /// before the `flags` keyword. |
| /// |
| /// # Derived traits |
| /// |
| /// The `PartialEq` and `Clone` traits are automatically derived for the `struct` using |
| /// the `deriving` attribute. Additional traits can be derived by providing an |
| /// explicit `deriving` attribute on `flags`. |
| /// |
| /// # Operators |
| /// |
| /// The following operator traits are implemented for the generated `struct`: |
| /// |
| /// - `BitOr`: union |
| /// - `BitAnd`: intersection |
| /// - `BitXor`: toggle |
| /// - `Sub`: set difference |
| /// - `Not`: set complement |
| /// |
| /// # Methods |
| /// |
| /// The following methods are defined for the generated `struct`: |
| /// |
| /// - `empty`: an empty set of flags |
| /// - `all`: the set of all flags |
| /// - `bits`: the raw value of the flags currently stored |
| /// - `from_bits`: convert from underlying bit representation, unless that |
| /// representation contains bits that do not correspond to a flag |
| /// - `from_bits_truncate`: convert from underlying bit representation, dropping |
| /// any bits that do not correspond to flags |
| /// - `is_empty`: `true` if no flags are currently stored |
| /// - `is_all`: `true` if all flags are currently set |
| /// - `intersects`: `true` if there are flags common to both `self` and `other` |
| /// - `contains`: `true` all of the flags in `other` are contained within `self` |
| /// - `insert`: inserts the specified flags in-place |
| /// - `remove`: removes the specified flags in-place |
| /// - `toggle`: the specified flags will be inserted if not present, and removed |
| /// if they are. |
| #[macro_export] |
| macro_rules! bitflags { |
| ($(#[$attr:meta])* flags $BitFlags:ident: $T:ty { |
| $($(#[$Flag_attr:meta])* const $Flag:ident = $value:expr),+ |
| }) => { |
| #[derive(Copy, PartialEq, Eq, Clone, PartialOrd, Ord, Hash)] |
| $(#[$attr])* |
| pub struct $BitFlags { |
| bits: $T, |
| } |
| |
| impl $BitFlags { |
| $($(#[$Flag_attr])* pub const $Flag: $BitFlags = $BitFlags { bits: $value };)+ |
| |
| /// Returns an empty set of flags. |
| #[inline] |
| pub fn empty() -> $BitFlags { |
| $BitFlags { bits: 0 } |
| } |
| |
| /// Returns the set containing all flags. |
| #[inline] |
| pub fn all() -> $BitFlags { |
| $BitFlags { bits: $($value)|+ } |
| } |
| |
| /// Returns the raw value of the flags currently stored. |
| #[inline] |
| pub fn bits(&self) -> $T { |
| self.bits |
| } |
| |
| /// Convert from underlying bit representation, unless that |
| /// representation contains bits that do not correspond to a flag. |
| #[inline] |
| pub fn from_bits(bits: $T) -> ::std::option::Option<$BitFlags> { |
| if (bits & !$BitFlags::all().bits()) != 0 { |
| ::std::option::Option::None |
| } else { |
| ::std::option::Option::Some($BitFlags { bits: bits }) |
| } |
| } |
| |
| /// Convert from underlying bit representation, dropping any bits |
| /// that do not correspond to flags. |
| #[inline] |
| pub fn from_bits_truncate(bits: $T) -> $BitFlags { |
| $BitFlags { bits: bits } & $BitFlags::all() |
| } |
| |
| /// Returns `true` if no flags are currently stored. |
| #[inline] |
| pub fn is_empty(&self) -> bool { |
| *self == $BitFlags::empty() |
| } |
| |
| /// Returns `true` if all flags are currently set. |
| #[inline] |
| pub fn is_all(&self) -> bool { |
| *self == $BitFlags::all() |
| } |
| |
| /// Returns `true` if there are flags common to both `self` and `other`. |
| #[inline] |
| pub fn intersects(&self, other: $BitFlags) -> bool { |
| !(*self & other).is_empty() |
| } |
| |
| /// Returns `true` all of the flags in `other` are contained within `self`. |
| #[inline] |
| pub fn contains(&self, other: $BitFlags) -> bool { |
| (*self & other) == other |
| } |
| |
| /// Inserts the specified flags in-place. |
| #[inline] |
| pub fn insert(&mut self, other: $BitFlags) { |
| self.bits |= other.bits; |
| } |
| |
| /// Removes the specified flags in-place. |
| #[inline] |
| pub fn remove(&mut self, other: $BitFlags) { |
| self.bits &= !other.bits; |
| } |
| |
| /// Toggles the specified flags in-place. |
| #[inline] |
| pub fn toggle(&mut self, other: $BitFlags) { |
| self.bits ^= other.bits; |
| } |
| } |
| |
| impl ::std::ops::BitOr for $BitFlags { |
| type Output = $BitFlags; |
| |
| /// Returns the union of the two sets of flags. |
| #[inline] |
| fn bitor(self, other: $BitFlags) -> $BitFlags { |
| $BitFlags { bits: self.bits | other.bits } |
| } |
| } |
| |
| impl ::std::ops::BitXor for $BitFlags { |
| type Output = $BitFlags; |
| |
| /// Returns the left flags, but with all the right flags toggled. |
| #[inline] |
| fn bitxor(self, other: $BitFlags) -> $BitFlags { |
| $BitFlags { bits: self.bits ^ other.bits } |
| } |
| } |
| |
| impl ::std::ops::BitAnd for $BitFlags { |
| type Output = $BitFlags; |
| |
| /// Returns the intersection between the two sets of flags. |
| #[inline] |
| fn bitand(self, other: $BitFlags) -> $BitFlags { |
| $BitFlags { bits: self.bits & other.bits } |
| } |
| } |
| |
| impl ::std::ops::Sub for $BitFlags { |
| type Output = $BitFlags; |
| |
| /// Returns the set difference of the two sets of flags. |
| #[inline] |
| fn sub(self, other: $BitFlags) -> $BitFlags { |
| $BitFlags { bits: self.bits & !other.bits } |
| } |
| } |
| |
| impl ::std::ops::Not for $BitFlags { |
| type Output = $BitFlags; |
| |
| /// Returns the complement of this set of flags. |
| #[inline] |
| fn not(self) -> $BitFlags { |
| $BitFlags { bits: !self.bits } & $BitFlags::all() |
| } |
| } |
| }; |
| ($(#[$attr:meta])* flags $BitFlags:ident: $T:ty { |
| $($(#[$Flag_attr:meta])* const $Flag:ident = $value:expr),+, |
| }) => { |
| bitflags! { |
| $(#[$attr])* |
| flags $BitFlags: $T { |
| $($(#[$Flag_attr])* const $Flag = $value),+ |
| } |
| } |
| }; |
| } |
| |
| #[cfg(test)] |
| #[allow(non_upper_case_globals)] |
| mod tests { |
| use std::hash::{Hasher, Hash, SipHasher}; |
| use std::option::Option::{Some, None}; |
| |
| bitflags! { |
| #[doc = "> The first principle is that you must not fool yourself — and"] |
| #[doc = "> you are the easiest person to fool."] |
| #[doc = "> "] |
| #[doc = "> - Richard Feynman"] |
| flags Flags: u32 { |
| const FlagA = 0b00000001, |
| #[doc = "<pcwalton> macros are way better at generating code than trans is"] |
| const FlagB = 0b00000010, |
| const FlagC = 0b00000100, |
| #[doc = "* cmr bed"] |
| #[doc = "* strcat table"] |
| #[doc = "<strcat> wait what?"] |
| const FlagABC = Flags::FlagA.bits |
| | Flags::FlagB.bits |
| | Flags::FlagC.bits, |
| } |
| } |
| |
| bitflags! { |
| flags AnotherSetOfFlags: i8 { |
| const AnotherFlag = -1, |
| } |
| } |
| |
| #[test] |
| fn test_bits(){ |
| assert_eq!(Flags::empty().bits(), 0b00000000); |
| assert_eq!(Flags::FlagA.bits(), 0b00000001); |
| assert_eq!(Flags::FlagABC.bits(), 0b00000111); |
| |
| assert_eq!(AnotherSetOfFlags::empty().bits(), 0b00); |
| assert_eq!(AnotherSetOfFlags::AnotherFlag.bits(), !0); |
| } |
| |
| #[test] |
| fn test_from_bits() { |
| assert!(Flags::from_bits(0) == Some(Flags::empty())); |
| assert!(Flags::from_bits(0b1) == Some(Flags::FlagA)); |
| assert!(Flags::from_bits(0b10) == Some(Flags::FlagB)); |
| assert!(Flags::from_bits(0b11) == Some(Flags::FlagA | Flags::FlagB)); |
| assert!(Flags::from_bits(0b1000) == None); |
| |
| assert!(AnotherSetOfFlags::from_bits(!0) == Some(AnotherSetOfFlags::AnotherFlag)); |
| } |
| |
| #[test] |
| fn test_from_bits_truncate() { |
| assert!(Flags::from_bits_truncate(0) == Flags::empty()); |
| assert!(Flags::from_bits_truncate(0b1) == Flags::FlagA); |
| assert!(Flags::from_bits_truncate(0b10) == Flags::FlagB); |
| assert!(Flags::from_bits_truncate(0b11) == (Flags::FlagA | Flags::FlagB)); |
| assert!(Flags::from_bits_truncate(0b1000) == Flags::empty()); |
| assert!(Flags::from_bits_truncate(0b1001) == Flags::FlagA); |
| |
| assert!(AnotherSetOfFlags::from_bits_truncate(0) == AnotherSetOfFlags::empty()); |
| } |
| |
| #[test] |
| fn test_is_empty(){ |
| assert!(Flags::empty().is_empty()); |
| assert!(!Flags::FlagA.is_empty()); |
| assert!(!Flags::FlagABC.is_empty()); |
| |
| assert!(!AnotherSetOfFlags::AnotherFlag.is_empty()); |
| } |
| |
| #[test] |
| fn test_is_all() { |
| assert!(Flags::all().is_all()); |
| assert!(!Flags::FlagA.is_all()); |
| assert!(Flags::FlagABC.is_all()); |
| |
| assert!(AnotherSetOfFlags::AnotherFlag.is_all()); |
| } |
| |
| #[test] |
| fn test_two_empties_do_not_intersect() { |
| let e1 = Flags::empty(); |
| let e2 = Flags::empty(); |
| assert!(!e1.intersects(e2)); |
| |
| assert!(AnotherSetOfFlags::AnotherFlag.intersects(AnotherSetOfFlags::AnotherFlag)); |
| } |
| |
| #[test] |
| fn test_empty_does_not_intersect_with_full() { |
| let e1 = Flags::empty(); |
| let e2 = Flags::FlagABC; |
| assert!(!e1.intersects(e2)); |
| } |
| |
| #[test] |
| fn test_disjoint_intersects() { |
| let e1 = Flags::FlagA; |
| let e2 = Flags::FlagB; |
| assert!(!e1.intersects(e2)); |
| } |
| |
| #[test] |
| fn test_overlapping_intersects() { |
| let e1 = Flags::FlagA; |
| let e2 = Flags::FlagA | Flags::FlagB; |
| assert!(e1.intersects(e2)); |
| } |
| |
| #[test] |
| fn test_contains() { |
| let e1 = Flags::FlagA; |
| let e2 = Flags::FlagA | Flags::FlagB; |
| assert!(!e1.contains(e2)); |
| assert!(e2.contains(e1)); |
| assert!(Flags::FlagABC.contains(e2)); |
| |
| assert!(AnotherSetOfFlags::AnotherFlag.contains(AnotherSetOfFlags::AnotherFlag)); |
| } |
| |
| #[test] |
| fn test_insert(){ |
| let mut e1 = Flags::FlagA; |
| let e2 = Flags::FlagA | Flags::FlagB; |
| e1.insert(e2); |
| assert!(e1 == e2); |
| |
| let mut e3 = AnotherSetOfFlags::empty(); |
| e3.insert(AnotherSetOfFlags::AnotherFlag); |
| assert!(e3 == AnotherSetOfFlags::AnotherFlag); |
| } |
| |
| #[test] |
| fn test_remove(){ |
| let mut e1 = Flags::FlagA | Flags::FlagB; |
| let e2 = Flags::FlagA | Flags::FlagC; |
| e1.remove(e2); |
| assert!(e1 == Flags::FlagB); |
| |
| let mut e3 = AnotherSetOfFlags::AnotherFlag; |
| e3.remove(AnotherSetOfFlags::AnotherFlag); |
| assert!(e3 == AnotherSetOfFlags::empty()); |
| } |
| |
| #[test] |
| fn test_operators() { |
| let e1 = Flags::FlagA | Flags::FlagC; |
| let e2 = Flags::FlagB | Flags::FlagC; |
| assert!((e1 | e2) == Flags::FlagABC); // union |
| assert!((e1 & e2) == Flags::FlagC); // intersection |
| assert!((e1 - e2) == Flags::FlagA); // set difference |
| assert!(!e2 == Flags::FlagA); // set complement |
| assert!(e1 ^ e2 == Flags::FlagA | Flags::FlagB); // toggle |
| let mut e3 = e1; |
| e3.toggle(e2); |
| assert!(e3 == Flags::FlagA | Flags::FlagB); |
| |
| let mut m4 = AnotherSetOfFlags::empty(); |
| m4.toggle(AnotherSetOfFlags::empty()); |
| assert!(m4 == AnotherSetOfFlags::empty()); |
| } |
| |
| #[test] |
| fn test_lt() { |
| let mut a = Flags::empty(); |
| let mut b = Flags::empty(); |
| |
| assert!(!(a < b) && !(b < a)); |
| b = Flags::FlagB; |
| assert!(a < b); |
| a = Flags::FlagC; |
| assert!(!(a < b) && b < a); |
| b = Flags::FlagC | Flags::FlagB; |
| assert!(a < b); |
| } |
| |
| #[test] |
| fn test_ord() { |
| let mut a = Flags::empty(); |
| let mut b = Flags::empty(); |
| |
| assert!(a <= b && a >= b); |
| a = Flags::FlagA; |
| assert!(a > b && a >= b); |
| assert!(b < a && b <= a); |
| b = Flags::FlagB; |
| assert!(b > a && b >= a); |
| assert!(a < b && a <= b); |
| } |
| |
| #[test] |
| fn test_hash() { |
| let mut x = Flags::empty(); |
| let mut y = Flags::empty(); |
| assert!(hash(&x) == hash(&y)); |
| x = Flags::all(); |
| y = Flags::FlagABC; |
| assert!(hash(&x) == hash(&y)); |
| } |
| |
| fn hash<T: Hash>(t: &T) -> u64 { |
| let mut s = SipHasher::new(); |
| t.hash(&mut s); |
| s.finish() |
| } |
| } |