commit 7741b4054a44f6ec235e02c2514061784ef13d13
Author: Avril <flanchan@cumallover.me>
Date:   Wed Aug 5 04:03:34 2020 +0100

    initial commit

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..80aca69
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,3 @@
+/target
+Cargo.lock
+*~
diff --git a/Cargo.toml b/Cargo.toml
new file mode 100644
index 0000000..ded86f3
--- /dev/null
+++ b/Cargo.toml
@@ -0,0 +1,13 @@
+[package]
+name = "readable-perms"
+version = "0.1.0"
+authors = ["Avril <flanchan@cumallover.me>"]
+edition = "2018"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+bitflags = "1.2"
+
+[build-dependencies]
+rustc_version = "0.2"
\ No newline at end of file
diff --git a/build.rs b/build.rs
new file mode 100644
index 0000000..6399463
--- /dev/null
+++ b/build.rs
@@ -0,0 +1,24 @@
+
+extern crate rustc_version;
+use rustc_version::{version, version_meta, Channel};
+
+fn main() {
+    // Assert we haven't travelled back in time
+    assert!(version().unwrap().major >= 1);
+
+    // Set cfg flags depending on release channel
+    match version_meta().unwrap().channel {
+        Channel::Stable => {
+            println!("cargo:rustc-cfg=stable");
+        }
+        Channel::Beta => {
+            println!("cargo:rustc-cfg=beta");
+        }
+        Channel::Nightly => {
+            println!("cargo:rustc-cfg=nightly");
+        }
+        Channel::Dev => {
+            println!("cargo:rustc-cfg=dev");
+        }
+    }
+}
diff --git a/src/lib.rs b/src/lib.rs
new file mode 100644
index 0000000..03ebac6
--- /dev/null
+++ b/src/lib.rs
@@ -0,0 +1,377 @@
+//! Unix permissions `mode_t` in readable format.
+//!
+//No I don't care about Microshaft wangblows
+#![allow(non_upper_case_globals)]
+#![allow(dead_code)]
+
+use bitflags::bitflags;
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+enum Class
+{
+    Owner(Bit),
+    Group(Bit),
+    Other(Bit),
+}
+
+impl Class
+{
+    /// Lmfao. Fuck bit masks and unix permissiong, `const fn` so idc
+    #[cfg(nightly)]
+    const fn mode(&self) -> u32
+    {
+	macro_rules! map {
+	    ($bit:expr, $bt:path, $constant:ident) => {
+		if $bit.contains($bt) {
+		    $constant
+		} else {
+		    0
+		}
+	    }
+	}
+	match self {
+	    Self::Owner(bit) => {
+		0u32 |
+		map!(bit, Bit::Read, MODE_USER_READ) |
+		map!(bit, Bit::Write, MODE_USER_WRITE) |
+		map!(bit, Bit::Execute, MODE_USER_EXECUTE)
+	    },
+	    Self::Group(bit) => {
+		0u32 |
+		map!(bit, Bit::Read, MODE_GROUP_READ) |
+		map!(bit, Bit::Write, MODE_GROUP_WRITE) |
+		map!(bit, Bit::Execute, MODE_GROUP_EXECUTE)
+	    },
+	    Self::Other(bit) => {
+		0u32 |
+		map!(bit, Bit::Read, MODE_OTHER_READ) |
+		map!(bit, Bit::Write, MODE_OTHER_WRITE) |
+		map!(bit, Bit::Execute, MODE_OTHER_EXECUTE)
+	    },
+	}
+    }
+    #[cfg(not(nightly))]
+    fn mode(&self) -> u32 //rip stable
+    {
+	macro_rules! map {
+	    ($bit:expr, $bt:path, $constant:ident) => {
+		if $bit.contains($bt) {
+		    $constant
+		} else {
+		    0
+		}
+	    }
+	}
+	match self {
+	    Self::Owner(bit) => {
+		0u32 |
+		map!(bit, Bit::Read, MODE_USER_READ) |
+		map!(bit, Bit::Write, MODE_USER_WRITE) |
+		map!(bit, Bit::Execute, MODE_USER_EXECUTE)
+	    },
+	    Self::Group(bit) => {
+		0u32 |
+		map!(bit, Bit::Read, MODE_GROUP_READ) |
+		map!(bit, Bit::Write, MODE_GROUP_WRITE) |
+		map!(bit, Bit::Execute, MODE_GROUP_EXECUTE)
+	    },
+	    Self::Other(bit) => {
+		0u32 |
+		map!(bit, Bit::Read, MODE_OTHER_READ) |
+		map!(bit, Bit::Write, MODE_OTHER_WRITE) |
+		map!(bit, Bit::Execute, MODE_OTHER_EXECUTE)
+	    },
+	}
+    }
+
+    #[cfg(nightly)]
+    const fn mask_mode(&self, bit: u32) -> Bit
+    {
+	macro_rules! map {
+	    ($bit:expr, $bt:path, $constant:ident) => {
+		if ($bit & $constant) == $constant {$bt.bits()} else {0u32}
+	    }
+	}
+	
+	Bit::from_bits_truncate(match self {
+	    Self::Owner(_) => {
+		map!(bit, Bit::Read, MODE_USER_READ) |
+		map!(bit, Bit::Write, MODE_USER_WRITE) |
+		map!(bit, Bit::Execute, MODE_USER_EXECUTE)
+	    },
+	    Self::Group(_) => {
+		map!(bit, Bit::Read, MODE_GROUP_READ) |
+		map!(bit, Bit::Write, MODE_GROUP_WRITE) |
+		map!(bit, Bit::Execute, MODE_GROUP_EXECUTE)
+	    },
+	    Self::Other(_) => {
+		map!(bit, Bit::Read, MODE_OTHER_READ) |
+		map!(bit, Bit::Write, MODE_OTHER_WRITE) |
+		map!(bit, Bit::Execute, MODE_OTHER_EXECUTE)
+	    },
+	})
+    }
+    
+    #[cfg(not(nightly))] 
+    fn mask_mode(&self, bit: u32) -> Bit
+    {
+	macro_rules! map {
+	    ($bit:expr, $bt:path, $constant:ident) => {
+		if ($bit & $constant) == $constant {$bt.bits()} else {0u32}
+	    }
+	}
+	
+	Bit::from_bits_truncate(match self {
+	    Self::Owner(_) => {
+		map!(bit, Bit::Read, MODE_USER_READ) |
+		map!(bit, Bit::Write, MODE_USER_WRITE) |
+		map!(bit, Bit::Execute, MODE_USER_EXECUTE)
+	    },
+	    Self::Group(_) => {
+		map!(bit, Bit::Read, MODE_GROUP_READ) |
+		map!(bit, Bit::Write, MODE_GROUP_WRITE) |
+		map!(bit, Bit::Execute, MODE_GROUP_EXECUTE)
+	    },
+	    Self::Other(_) => {
+		map!(bit, Bit::Read, MODE_OTHER_READ) |
+		map!(bit, Bit::Write, MODE_OTHER_WRITE) |
+		map!(bit, Bit::Execute, MODE_OTHER_EXECUTE)
+	    },
+	})
+    }
+}
+
+const MODE_USER: u32 = 0o700;
+const MODE_USER_READ: u32 = 0o400;
+const MODE_USER_WRITE: u32 = 0o200;
+const MODE_USER_EXECUTE: u32 = 0o100;
+
+const MODE_GROUP: u32 = 0o70;
+const MODE_GROUP_READ: u32 = 0o40;
+const MODE_GROUP_WRITE: u32 = 0o20;
+const MODE_GROUP_EXECUTE: u32 = 0o10;
+
+const MODE_OTHER: u32 = 0o7;
+const MODE_OTHER_READ: u32 = 0o4;
+const MODE_OTHER_WRITE: u32 = 0o2;
+const MODE_OTHER_EXECUTE: u32 = 0o1;
+
+const MODE: u32 = 0o777;
+
+bitflags!{
+    /// The mode mask for each individual class of `User`.
+    ///
+    /// # Notes
+    /// No this does not map directly to `mode_t`. Use `User.mode(bits)` and `User.from_mode(mode)`.
+    pub struct Bit: u32 {
+	const None = 0;
+	const Read = 1;
+	const Write = 2;
+	const Execute = 4;
+	const Mask = 7;
+    }
+}
+
+bitflags!{
+    // not supported, don't care
+    struct StickyBit: u32{
+	const None = 0;
+	const Setuid = 0o40000;
+	const Setgid = 0o20000;
+	const SaveSwap = 0o10000;
+	
+    }
+}
+
+/// Permissions struct in readable format
+#[derive(Debug, Clone, PartialEq, Eq, Hash, Copy, Ord, PartialOrd)]
+pub struct Permissions
+{
+    
+    pub u_owner: Bit,
+    pub u_group: Bit,
+    pub u_other: Bit,
+    
+    _u_sticky: StickyBit, //idc about this either
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash, Copy)]
+pub enum User
+{
+    Owner,
+    Group,
+    Other,
+}
+
+impl User
+{
+    /// Convert this class's representation of `Bit` into the corresponding `mode_t`.
+    pub const fn mode(self, mask: Bit) -> u32
+    {
+	match self {
+	    User::Owner => Class::Owner(mask).mode(),
+	    User::Group => Class::Group(mask).mode(),
+	    User::Other => Class::Other(mask).mode(),
+	}
+    }
+
+    /// Convert a `mode_t` `u32` into `Bit` with this class' user.
+    pub const fn from_mode(self, mask: u32) -> Bit
+    {
+	match self {
+	    User::Owner => Class::Owner(Bit::Mask).mask_mode(mask),
+	    User::Group => Class::Group(Bit::Mask).mask_mode(mask),
+	    User::Other => Class::Other(Bit::Mask).mask_mode(mask),
+	}
+    }
+}
+
+impl Default for Permissions
+{
+    #[inline] fn default() -> Self
+    {
+	Self::new()
+    }
+}
+
+impl Permissions
+{
+    /// Create a new empty `Permissions` struct
+    pub const fn new() -> Self
+    {
+	Self {
+	    u_owner: Bit::None,
+	    u_group: Bit::None,
+	    u_other: Bit::None,
+	    _u_sticky: StickyBit::None,
+	}
+    }
+}
+
+// Mask impl
+impl Permissions
+{
+    #[inline] const fn c_owner(&self) -> Class
+    {
+	Class::Owner(self.u_owner)
+    }
+    #[inline] const fn c_group(&self) -> Class
+    {
+	Class::Group(self.u_group)
+    }
+    #[inline] const fn c_other(&self) -> Class
+    {
+	Class::Other(self.u_other)
+    }
+
+    /// Convert into `mode_t` repr.
+    #[inline] pub const fn mask(&self) -> u32
+    {
+	self.c_owner().mode() |
+	self.c_group().mode() |
+	self.c_other().mode()
+    }
+
+    /// Convert from `mode_t` repr.
+    #[inline] pub const fn from_mask(bit: u32) -> Self
+    {
+	Self{
+	    u_owner: Class::Owner(Bit::Mask).mask_mode(bit),
+	    u_group: Class::Group(Bit::Mask).mask_mode(bit),
+	    u_other: Class::Other(Bit::Mask).mask_mode(bit),
+
+	    _u_sticky: StickyBit::None,
+	}
+    }
+
+    /// Consume and add a mask.
+    ///
+    /// # Usage
+    /// For builder pattern
+    #[inline] pub const fn add_mask(self, class: User, bit: Bit) -> Self
+    {
+	match class {
+	    User::Owner => {
+		Self {
+		    u_owner: Bit::from_bits_truncate(self.u_owner.bits() | bit.bits()),
+		    ..self
+		}
+	    },
+	    User::Group => {
+		Self {
+		    u_group: Bit::from_bits_truncate(self.u_group.bits() | bit.bits()),
+		    ..self
+		}
+	    },
+	    User::Other => {
+		Self {
+		    u_other: Bit::from_bits_truncate(self.u_other.bits() | bit.bits()),
+		    ..self
+		}
+	    },
+	}
+    }
+
+    
+    /// Consume and remove a mask.
+    ///
+    /// # Usage
+    /// For builder pattern
+    #[inline] pub const fn remove_mask(self, class: User, bit: Bit) -> Self
+    {
+	match class {
+	    User::Owner => {
+		Self {
+		    u_owner: Bit::from_bits_truncate(self.u_owner.bits() & !bit.bits()),
+		    ..self
+		}
+	    },
+	    User::Group => {
+		Self {
+		    u_group: Bit::from_bits_truncate(self.u_group.bits() & !bit.bits()),
+		    ..self
+		}
+	    },
+	    User::Other => {
+		Self {
+		    u_other: Bit::from_bits_truncate(self.u_other.bits() & !bit.bits()),
+		    ..self
+		}
+	    },
+	}
+    }
+
+    /// Returns true if the specified mode mask is all present
+    #[inline] pub const fn has_mask(&self, class: User, bit: Bit) -> bool
+    {
+	match class {
+	    User::Owner => {
+		(self.u_owner.bits() & bit.bits()) == bit.bits()
+	    },
+	    User::Group => {
+		(self.u_group.bits() & bit.bits()) == bit.bits()
+	    },
+	    User::Other => {
+		(self.u_other.bits() & bit.bits()) == bit.bits()
+	    },
+	}
+    }
+}
+
+impl From<Permissions> for u32
+{
+    #[inline] fn from(from: Permissions) -> Self
+    {
+	from.mask()
+    }
+}
+
+impl From<u32> for Permissions
+{
+    #[inline] fn from(from: u32) -> Self
+    {
+	Self::from_mask(from)
+    }
+}
+
+mod test;
diff --git a/src/test.rs b/src/test.rs
new file mode 100644
index 0000000..a249bc0
--- /dev/null
+++ b/src/test.rs
@@ -0,0 +1,24 @@
+#![cfg(test)]
+
+use super::*;
+
+#[test]
+fn mask()
+{
+    assert_eq!(Permissions::new()
+	       .add_mask(User::Owner, Bit::Mask)
+	       .add_mask(User::Group, Bit::Read | Bit::Execute)
+	       .add_mask(User::Other, Bit::Read | Bit::Write)
+	       .remove_mask(User::Other, Bit::Write)
+	       .mask(),
+	       0o754);
+}
+
+#[test]
+fn from_mask()
+{
+    let mask = Permissions::from_mask(0o754);
+    assert!(mask.has_mask(User::Owner, Bit::Mask));
+    assert!(mask.has_mask(User::Group, Bit::Read | Bit::Execute));
+    assert!(mask.has_mask(User::Other, Bit::Read));
+}