rustix/backend/linux_raw/
reg.rs#![allow(unsafe_code)]
use super::c;
use super::fd::RawFd;
use core::marker::PhantomData;
use core::ops::Range;
pub(super) trait ToAsm: private::Sealed {
#[must_use]
unsafe fn to_asm(self) -> *mut Opaque;
}
pub(super) trait FromAsm: private::Sealed {
#[must_use]
unsafe fn from_asm(raw: *mut Opaque) -> Self;
}
#[repr(transparent)]
pub(super) struct Opaque(c::c_void);
pub(super) struct A0(());
pub(super) struct A1(());
pub(super) struct A2(());
pub(super) struct A3(());
pub(super) struct A4(());
pub(super) struct A5(());
#[cfg(any(target_arch = "mips", target_arch = "mips32r6"))]
pub(super) struct A6(());
#[cfg(target_arch = "x86")]
pub(super) struct SocketArg;
pub(super) trait ArgNumber: private::Sealed {}
impl ArgNumber for A0 {}
impl ArgNumber for A1 {}
impl ArgNumber for A2 {}
impl ArgNumber for A3 {}
impl ArgNumber for A4 {}
impl ArgNumber for A5 {}
#[cfg(any(target_arch = "mips", target_arch = "mips32r6"))]
impl ArgNumber for A6 {}
#[cfg(target_arch = "x86")]
impl ArgNumber for SocketArg {}
pub(super) struct R0(());
pub(super) trait RetNumber: private::Sealed {}
impl RetNumber for R0 {}
#[repr(transparent)]
#[must_use]
pub(super) struct ArgReg<'a, Num: ArgNumber> {
raw: *mut Opaque,
_phantom: PhantomData<(&'a (), Num)>,
}
impl<'a, Num: ArgNumber> ToAsm for ArgReg<'a, Num> {
#[inline]
unsafe fn to_asm(self) -> *mut Opaque {
self.raw
}
}
#[repr(transparent)]
#[must_use]
pub(super) struct RetReg<Num: RetNumber> {
raw: *mut Opaque,
_phantom: PhantomData<Num>,
}
impl<Num: RetNumber> RetReg<Num> {
#[inline]
pub(super) fn decode_usize(self) -> usize {
debug_assert!(!(-4095..0).contains(&(self.raw as isize)));
self.raw as usize
}
#[inline]
pub(super) fn decode_raw_fd(self) -> RawFd {
let bits = self.decode_usize();
let raw_fd = bits as RawFd;
debug_assert_eq!(raw_fd as usize, bits);
raw_fd
}
#[inline]
pub(super) fn decode_c_int(self) -> c::c_int {
let bits = self.decode_usize();
let c_int_ = bits as c::c_int;
debug_assert_eq!(c_int_ as usize, bits);
c_int_
}
#[inline]
pub(super) fn decode_c_uint(self) -> c::c_uint {
let bits = self.decode_usize();
let c_uint_ = bits as c::c_uint;
debug_assert_eq!(c_uint_ as usize, bits);
c_uint_
}
#[inline]
pub(super) fn decode_void_star(self) -> *mut c::c_void {
self.raw.cast()
}
#[cfg(target_pointer_width = "64")]
#[inline]
pub(super) fn decode_u64(self) -> u64 {
self.decode_usize() as u64
}
#[inline]
pub(super) fn decode_void(self) {
let ignore = self.decode_usize();
debug_assert_eq!(ignore, 0);
}
#[inline]
pub(super) fn decode_error_code(self) -> u16 {
let bits = self.raw as usize;
debug_assert!((-4095..0).contains(&(bits as isize)));
bits as u16
}
#[inline]
pub(super) fn is_nonzero(&self) -> bool {
!self.raw.is_null()
}
#[inline]
pub(super) fn is_negative(&self) -> bool {
(self.raw as isize) < 0
}
#[inline]
pub(super) fn is_in_range(&self, range: Range<isize>) -> bool {
range.contains(&(self.raw as isize))
}
}
impl<Num: RetNumber> FromAsm for RetReg<Num> {
#[inline]
unsafe fn from_asm(raw: *mut Opaque) -> Self {
Self {
raw,
_phantom: PhantomData,
}
}
}
#[repr(transparent)]
pub(super) struct SyscallNumber<'a> {
nr: usize,
_phantom: PhantomData<&'a ()>,
}
impl<'a> ToAsm for SyscallNumber<'a> {
#[inline]
unsafe fn to_asm(self) -> *mut Opaque {
self.nr as usize as *mut Opaque
}
}
#[inline]
pub(super) fn raw_arg<'a, Num: ArgNumber>(raw: *mut Opaque) -> ArgReg<'a, Num> {
ArgReg {
raw,
_phantom: PhantomData,
}
}
#[inline]
pub(super) const fn nr<'a>(nr: u32) -> SyscallNumber<'a> {
SyscallNumber {
nr: nr as usize,
_phantom: PhantomData,
}
}
mod private {
pub trait Sealed {}
impl<'a, Num: super::ArgNumber> Sealed for super::ArgReg<'a, Num> {}
impl<Num: super::RetNumber> Sealed for super::RetReg<Num> {}
impl<'a> Sealed for super::SyscallNumber<'a> {}
impl Sealed for super::A0 {}
impl Sealed for super::A1 {}
impl Sealed for super::A2 {}
impl Sealed for super::A3 {}
impl Sealed for super::A4 {}
impl Sealed for super::A5 {}
#[cfg(any(target_arch = "mips", target_arch = "mips32r6"))]
impl Sealed for super::A6 {}
#[cfg(target_arch = "x86")]
impl Sealed for super::SocketArg {}
impl Sealed for super::R0 {}
}