1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147

use std::{cmp, fmt, hash, mem, str};
use std::marker::PhantomData;
use crate::Pod;

/// Typed relative virtual address.
#[repr(transparent)]
pub struct Pir<T: ?Sized = ()> {
	rva: u32,
	marker: PhantomData<fn() -> T>,
}

impl<T: ?Sized> Pir<T> {
	/// Null pointer constant.
	pub const NULL: Pir<T> = Pir { rva: 0, marker: PhantomData };
	/// Creates a null pointer.
	pub fn null() -> Pir<T> {
		Pir::NULL
	}
	/// Returns true if the pointer is null.
	pub fn is_null(self) -> bool {
		self.rva == 0
	}
	/// Casts the pointer to a different type keeping the pointer address fixed.
	pub fn cast<U: ?Sized>(self) -> Pir<U> {
		Pir { rva: self.rva, marker: PhantomData }
	}
	/// Offsets and casts the pointer to a differen type.
	///
	/// Because the type of the current and the target may be unrelated, this is a byte offset.
	pub fn offset<U: ?Sized>(self, offset: i32) -> Pir<U> {
		let rva = self.rva.wrapping_add(offset as u32);
		Pir { rva, marker: PhantomData }
	}
	/// Returns the raw integer, type ascription helper.
	pub fn into_raw(self) -> u32 {
		self.rva
	}
	/// Formats the pointer.
	fn fmt(self) -> [u8; 10] {
		let mut s = [0; 10];
		s[0] = b'0';
		s[1] = b'x';
		let mut rva = self.rva;
		for i in 0..8 {
			rva = rva.rotate_left(4);
			let digit = (rva & 0xf) as u8;
			let chr = if digit < 10 { b'0' + digit } else { b'a' + (digit - 10) };
			s[i + 2] = chr;
		}
		return s;
	}
}
impl<T> Pir<[T]> {
	/// Decays the pointer from `[T]` to `T`.
	pub fn decay(self) -> Pir<T> {
		Pir { rva: self.rva, marker: PhantomData }
	}
	/// Pointer arithmetic, gets the pointer of an element at the specified index.
	pub fn at(self, i: usize) -> Pir<T> {
		let rva = self.rva + (i * mem::size_of::<T>()) as u32;
		Pir { rva, marker: PhantomData }
	}
}

unsafe impl<T: ?Sized> Pod for Pir<T> where Pir<T>: 'static {}

impl<T: ?Sized> Copy for Pir<T> {}
impl<T: ?Sized> Clone for Pir<T> {
	fn clone(&self) -> Pir<T> {
		*self
	}
}
impl<T: ?Sized> Default for Pir<T> {
	fn default() -> Pir<T> {
		Pir::NULL
	}
}
impl<T: ?Sized> Eq for Pir<T> {}
impl<T: ?Sized> PartialEq for Pir<T> {
	fn eq(&self, rhs: &Pir<T>) -> bool {
		self.rva == rhs.rva
	}
}
impl<T: ?Sized> PartialOrd for Pir<T> {
	fn partial_cmp(&self, rhs: &Pir<T>) -> Option<cmp::Ordering> {
		self.rva.partial_cmp(&rhs.rva)
	}
}
impl<T: ?Sized> Ord for Pir<T> {
	fn cmp(&self, rhs: &Pir<T>) -> cmp::Ordering {
		self.rva.cmp(&rhs.rva)
	}
}
impl<T: ?Sized> hash::Hash for Pir<T> {
	fn hash<H: hash::Hasher>(&self, state: &mut H) {
		self.rva.hash(state)
	}
}
impl<T: ?Sized> From<u32> for Pir<T> {
	fn from(rva: u32) -> Pir<T> {
		Pir { rva, marker: PhantomData }
	}
}
impl<T: ?Sized> From<Pir<T>> for u32 {
	fn from(pir: Pir<T>) -> u32 {
		pir.rva
	}
}
impl<T: ?Sized> AsRef<u32> for Pir<T> {
	fn as_ref(&self) -> &u32 {
		&self.rva
	}
}
impl<T: ?Sized> AsMut<u32> for Pir<T> {
	fn as_mut(&mut self) -> &mut u32 {
		&mut self.rva
	}
}
impl<T: ?Sized> fmt::Debug for Pir<T> {
	fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
		let buf = Pir::fmt(*self);
		f.write_str(unsafe { str::from_utf8_unchecked(&buf) })
	}
}
impl<T: ?Sized> fmt::UpperHex for Pir<T> {
	fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
		self.rva.fmt(f)
	}
}
impl<T: ?Sized> fmt::LowerHex for Pir<T> {
	fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
		self.rva.fmt(f)
	}
}
impl<T: ?Sized> fmt::Display for Pir<T> {
	fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
		let buf = Pir::fmt(*self);
		f.write_str(unsafe { str::from_utf8_unchecked(&buf) })
	}
}

#[cfg(feature = "serde")]
impl<T: ?Sized> serde::Serialize for Pir<T> {
	fn serialize<S: serde::Serializer>(&self, serializer: S) -> Result<S::Ok, S::Error> {
		serializer.serialize_u32(self.rva)
	}
}