diff options
Diffstat (limited to 'vendor/rustix/src/backend/libc/thread/syscalls.rs')
| -rw-r--r-- | vendor/rustix/src/backend/libc/thread/syscalls.rs | 523 |
1 files changed, 523 insertions, 0 deletions
diff --git a/vendor/rustix/src/backend/libc/thread/syscalls.rs b/vendor/rustix/src/backend/libc/thread/syscalls.rs new file mode 100644 index 0000000..33750f4 --- /dev/null +++ b/vendor/rustix/src/backend/libc/thread/syscalls.rs @@ -0,0 +1,523 @@ +//! libc syscalls supporting `rustix::thread`. + +use crate::backend::c; +use crate::backend::conv::ret; +use crate::io; +#[cfg(not(target_os = "redox"))] +use crate::thread::{NanosleepRelativeResult, Timespec}; +#[cfg(all(target_env = "gnu", fix_y2038))] +use crate::timespec::LibcTimespec; +use core::mem::MaybeUninit; +#[cfg(linux_kernel)] +use { + crate::backend::conv::{borrowed_fd, ret_c_int, ret_usize}, + crate::fd::BorrowedFd, + crate::pid::Pid, + crate::thread::{FutexFlags, FutexOperation}, + crate::utils::as_mut_ptr, +}; +#[cfg(not(any( + apple, + freebsdlike, + target_os = "emscripten", + target_os = "espidf", + target_os = "haiku", + target_os = "openbsd", + target_os = "redox", + target_os = "vita", + target_os = "wasi", +)))] +use {crate::thread::ClockId, core::ptr::null_mut}; + +#[cfg(all(target_env = "gnu", fix_y2038))] +weak!(fn __clock_nanosleep_time64(c::clockid_t, c::c_int, *const LibcTimespec, *mut LibcTimespec) -> c::c_int); +#[cfg(all(target_env = "gnu", fix_y2038))] +weak!(fn __nanosleep64(*const LibcTimespec, *mut LibcTimespec) -> c::c_int); + +#[cfg(not(any( + apple, + target_os = "dragonfly", + target_os = "emscripten", + target_os = "espidf", + target_os = "freebsd", // FreeBSD 12 has clock_nanosleep, but libc targets FreeBSD 11. + target_os = "haiku", + target_os = "openbsd", + target_os = "redox", + target_os = "vita", + target_os = "wasi", +)))] +#[inline] +pub(crate) fn clock_nanosleep_relative(id: ClockId, request: &Timespec) -> NanosleepRelativeResult { + // Old 32-bit version: libc has `clock_nanosleep` but it is not y2038 safe + // by default. But there may be a `__clock_nanosleep_time64` we can use. + #[cfg(fix_y2038)] + { + #[cfg(target_env = "gnu")] + if let Some(libc_clock_nanosleep) = __clock_nanosleep_time64.get() { + let flags = 0; + let mut remain = MaybeUninit::<LibcTimespec>::uninit(); + + unsafe { + return match libc_clock_nanosleep( + id as c::clockid_t, + flags, + &request.clone().into(), + remain.as_mut_ptr(), + ) { + 0 => NanosleepRelativeResult::Ok, + err if err == io::Errno::INTR.0 => { + NanosleepRelativeResult::Interrupted(remain.assume_init().into()) + } + err => NanosleepRelativeResult::Err(io::Errno(err)), + }; + } + } + + clock_nanosleep_relative_old(id, request) + } + + // Main version: libc is y2038 safe and has `clock_nanosleep`. + #[cfg(not(fix_y2038))] + unsafe { + let flags = 0; + let mut remain = MaybeUninit::<Timespec>::uninit(); + + match c::clock_nanosleep(id as c::clockid_t, flags, request, remain.as_mut_ptr()) { + 0 => NanosleepRelativeResult::Ok, + err if err == io::Errno::INTR.0 => { + NanosleepRelativeResult::Interrupted(remain.assume_init()) + } + err => NanosleepRelativeResult::Err(io::Errno(err)), + } + } +} + +#[cfg(all( + fix_y2038, + not(any( + apple, + target_os = "emscripten", + target_os = "haiku", + target_os = "vita" + )) +))] +fn clock_nanosleep_relative_old(id: ClockId, request: &Timespec) -> NanosleepRelativeResult { + let tv_sec = match request.tv_sec.try_into() { + Ok(tv_sec) => tv_sec, + Err(_) => return NanosleepRelativeResult::Err(io::Errno::OVERFLOW), + }; + let tv_nsec = match request.tv_nsec.try_into() { + Ok(tv_nsec) => tv_nsec, + Err(_) => return NanosleepRelativeResult::Err(io::Errno::INVAL), + }; + let old_request = c::timespec { tv_sec, tv_nsec }; + let mut old_remain = MaybeUninit::<c::timespec>::uninit(); + let flags = 0; + + unsafe { + match c::clock_nanosleep( + id as c::clockid_t, + flags, + &old_request, + old_remain.as_mut_ptr(), + ) { + 0 => NanosleepRelativeResult::Ok, + err if err == io::Errno::INTR.0 => { + let old_remain = old_remain.assume_init(); + let remain = Timespec { + tv_sec: old_remain.tv_sec.into(), + tv_nsec: old_remain.tv_nsec.into(), + }; + NanosleepRelativeResult::Interrupted(remain) + } + err => NanosleepRelativeResult::Err(io::Errno(err)), + } + } +} + +#[cfg(not(any( + apple, + target_os = "dragonfly", + target_os = "emscripten", + target_os = "espidf", + target_os = "freebsd", // FreeBSD 12 has clock_nanosleep, but libc targets FreeBSD 11. + target_os = "haiku", + target_os = "openbsd", + target_os = "redox", + target_os = "vita", + target_os = "wasi", +)))] +#[inline] +pub(crate) fn clock_nanosleep_absolute(id: ClockId, request: &Timespec) -> io::Result<()> { + // Old 32-bit version: libc has `clock_nanosleep` but it is not y2038 safe + // by default. But there may be a `__clock_nanosleep_time64` we can use. + #[cfg(fix_y2038)] + { + #[cfg(target_env = "gnu")] + if let Some(libc_clock_nanosleep) = __clock_nanosleep_time64.get() { + let flags = c::TIMER_ABSTIME; + unsafe { + return match { + libc_clock_nanosleep( + id as c::clockid_t, + flags, + &request.clone().into(), + null_mut(), + ) + } { + 0 => Ok(()), + err => Err(io::Errno(err)), + }; + } + } + + clock_nanosleep_absolute_old(id, request) + } + + // Main version: libc is y2038 safe and has `clock_nanosleep`. + #[cfg(not(fix_y2038))] + { + let flags = c::TIMER_ABSTIME; + + match unsafe { c::clock_nanosleep(id as c::clockid_t, flags as _, request, null_mut()) } { + 0 => Ok(()), + err => Err(io::Errno(err)), + } + } +} + +#[cfg(all( + fix_y2038, + not(any( + apple, + target_os = "emscripten", + target_os = "haiku", + target_os = "vita" + )) +))] +fn clock_nanosleep_absolute_old(id: ClockId, request: &Timespec) -> io::Result<()> { + let flags = c::TIMER_ABSTIME; + + let old_request = c::timespec { + tv_sec: request.tv_sec.try_into().map_err(|_| io::Errno::OVERFLOW)?, + tv_nsec: request.tv_nsec.try_into().map_err(|_| io::Errno::INVAL)?, + }; + match unsafe { c::clock_nanosleep(id as c::clockid_t, flags, &old_request, null_mut()) } { + 0 => Ok(()), + err => Err(io::Errno(err)), + } +} + +#[cfg(not(target_os = "redox"))] +#[inline] +pub(crate) fn nanosleep(request: &Timespec) -> NanosleepRelativeResult { + // Old 32-bit version: libc has `nanosleep` but it is not y2038 safe by + // default. But there may be a `__nanosleep64` we can use. + #[cfg(fix_y2038)] + { + #[cfg(target_env = "gnu")] + if let Some(libc_nanosleep) = __nanosleep64.get() { + let mut remain = MaybeUninit::<LibcTimespec>::uninit(); + unsafe { + return match ret(libc_nanosleep(&request.clone().into(), remain.as_mut_ptr())) { + Ok(()) => NanosleepRelativeResult::Ok, + Err(io::Errno::INTR) => { + NanosleepRelativeResult::Interrupted(remain.assume_init().into()) + } + Err(err) => NanosleepRelativeResult::Err(err), + }; + } + } + + nanosleep_old(request) + } + + // Main version: libc is y2038 safe and has `nanosleep`. + #[cfg(not(fix_y2038))] + unsafe { + let mut remain = MaybeUninit::<Timespec>::uninit(); + + match ret(c::nanosleep(request, remain.as_mut_ptr())) { + Ok(()) => NanosleepRelativeResult::Ok, + Err(io::Errno::INTR) => NanosleepRelativeResult::Interrupted(remain.assume_init()), + Err(err) => NanosleepRelativeResult::Err(err), + } + } +} + +#[cfg(fix_y2038)] +fn nanosleep_old(request: &Timespec) -> NanosleepRelativeResult { + let tv_sec = match request.tv_sec.try_into() { + Ok(tv_sec) => tv_sec, + Err(_) => return NanosleepRelativeResult::Err(io::Errno::OVERFLOW), + }; + let tv_nsec = match request.tv_nsec.try_into() { + Ok(tv_nsec) => tv_nsec, + Err(_) => return NanosleepRelativeResult::Err(io::Errno::INVAL), + }; + let old_request = c::timespec { tv_sec, tv_nsec }; + let mut old_remain = MaybeUninit::<c::timespec>::uninit(); + + unsafe { + match ret(c::nanosleep(&old_request, old_remain.as_mut_ptr())) { + Ok(()) => NanosleepRelativeResult::Ok, + Err(io::Errno::INTR) => { + let old_remain = old_remain.assume_init(); + let remain = Timespec { + tv_sec: old_remain.tv_sec.into(), + tv_nsec: old_remain.tv_nsec.into(), + }; + NanosleepRelativeResult::Interrupted(remain) + } + Err(err) => NanosleepRelativeResult::Err(err), + } + } +} + +#[cfg(linux_kernel)] +#[inline] +#[must_use] +pub(crate) fn gettid() -> Pid { + // `gettid` wasn't supported in glibc until 2.30, and musl until 1.2.2, + // so use `syscall`. + // <https://sourceware.org/bugzilla/show_bug.cgi?id=6399#c62> + weak_or_syscall! { + fn gettid() via SYS_gettid -> c::pid_t + } + + unsafe { + let tid = gettid(); + Pid::from_raw_unchecked(tid) + } +} + +#[cfg(linux_kernel)] +#[inline] +pub(crate) fn setns(fd: BorrowedFd<'_>, nstype: c::c_int) -> io::Result<c::c_int> { + // `setns` wasn't supported in glibc until 2.14, and musl until 0.9.5, + // so use `syscall`. + weak_or_syscall! { + fn setns(fd: c::c_int, nstype: c::c_int) via SYS_setns -> c::c_int + } + + unsafe { ret_c_int(setns(borrowed_fd(fd), nstype)) } +} + +#[cfg(linux_kernel)] +#[inline] +pub(crate) fn unshare(flags: crate::thread::UnshareFlags) -> io::Result<()> { + unsafe { ret(c::unshare(flags.bits() as i32)) } +} + +#[cfg(linux_kernel)] +#[inline] +pub(crate) fn capget( + header: &mut linux_raw_sys::general::__user_cap_header_struct, + data: &mut [MaybeUninit<linux_raw_sys::general::__user_cap_data_struct>], +) -> io::Result<()> { + syscall! { + fn capget( + hdrp: *mut linux_raw_sys::general::__user_cap_header_struct, + data: *mut linux_raw_sys::general::__user_cap_data_struct + ) via SYS_capget -> c::c_int + } + + unsafe { + ret(capget( + as_mut_ptr(header), + data.as_mut_ptr() + .cast::<linux_raw_sys::general::__user_cap_data_struct>(), + )) + } +} + +#[cfg(linux_kernel)] +#[inline] +pub(crate) fn capset( + header: &mut linux_raw_sys::general::__user_cap_header_struct, + data: &[linux_raw_sys::general::__user_cap_data_struct], +) -> io::Result<()> { + syscall! { + fn capset( + hdrp: *mut linux_raw_sys::general::__user_cap_header_struct, + data: *const linux_raw_sys::general::__user_cap_data_struct + ) via SYS_capset -> c::c_int + } + + unsafe { ret(capset(as_mut_ptr(header), data.as_ptr())) } +} + +#[cfg(linux_kernel)] +#[inline] +pub(crate) fn setuid_thread(uid: crate::ugid::Uid) -> io::Result<()> { + syscall! { + fn setuid(uid: c::uid_t) via SYS_setuid -> c::c_int + } + + unsafe { ret(setuid(uid.as_raw())) } +} + +#[cfg(linux_kernel)] +#[inline] +pub(crate) fn setresuid_thread( + ruid: crate::ugid::Uid, + euid: crate::ugid::Uid, + suid: crate::ugid::Uid, +) -> io::Result<()> { + #[cfg(any(target_arch = "x86", target_arch = "arm", target_arch = "sparc"))] + const SYS: c::c_long = c::SYS_setresuid32 as c::c_long; + #[cfg(not(any(target_arch = "x86", target_arch = "arm", target_arch = "sparc")))] + const SYS: c::c_long = c::SYS_setresuid as c::c_long; + + syscall! { + fn setresuid(ruid: c::uid_t, euid: c::uid_t, suid: c::uid_t) via SYS -> c::c_int + } + + unsafe { ret(setresuid(ruid.as_raw(), euid.as_raw(), suid.as_raw())) } +} + +#[cfg(linux_kernel)] +#[inline] +pub(crate) fn setgid_thread(gid: crate::ugid::Gid) -> io::Result<()> { + syscall! { + fn setgid(gid: c::gid_t) via SYS_setgid -> c::c_int + } + + unsafe { ret(setgid(gid.as_raw())) } +} + +#[cfg(linux_kernel)] +#[inline] +pub(crate) fn setresgid_thread( + rgid: crate::ugid::Gid, + egid: crate::ugid::Gid, + sgid: crate::ugid::Gid, +) -> io::Result<()> { + #[cfg(any(target_arch = "x86", target_arch = "arm", target_arch = "sparc"))] + const SYS: c::c_long = c::SYS_setresgid32 as c::c_long; + #[cfg(not(any(target_arch = "x86", target_arch = "arm", target_arch = "sparc")))] + const SYS: c::c_long = c::SYS_setresgid as c::c_long; + + syscall! { + fn setresgid(rgid: c::gid_t, egid: c::gid_t, sgid: c::gid_t) via SYS -> c::c_int + } + + unsafe { ret(setresgid(rgid.as_raw(), egid.as_raw(), sgid.as_raw())) } +} + +// TODO: This could be de-multiplexed. +#[cfg(linux_kernel)] +pub(crate) unsafe fn futex( + uaddr: *mut u32, + op: FutexOperation, + flags: FutexFlags, + val: u32, + utime: *const Timespec, + uaddr2: *mut u32, + val3: u32, +) -> io::Result<usize> { + #[cfg(all( + target_pointer_width = "32", + not(any(target_arch = "aarch64", target_arch = "x86_64")) + ))] + { + // TODO: Upstream this to the libc crate. + #[allow(non_upper_case_globals)] + const SYS_futex_time64: i32 = linux_raw_sys::general::__NR_futex_time64 as i32; + + syscall! { + fn futex_time64( + uaddr: *mut u32, + futex_op: c::c_int, + val: u32, + timeout: *const Timespec, + uaddr2: *mut u32, + val3: u32 + ) via SYS_futex_time64 -> c::ssize_t + } + + ret_usize(futex_time64( + uaddr, + op as i32 | flags.bits() as i32, + val, + utime, + uaddr2, + val3, + )) + .or_else(|err| { + // See the comments in `rustix_clock_gettime_via_syscall` about + // emulation. + if err == io::Errno::NOSYS { + futex_old(uaddr, op, flags, val, utime, uaddr2, val3) + } else { + Err(err) + } + }) + } + + #[cfg(any( + target_pointer_width = "64", + target_arch = "aarch64", + target_arch = "x86_64" + ))] + { + syscall! { + fn futex( + uaddr: *mut u32, + futex_op: c::c_int, + val: u32, + timeout: *const linux_raw_sys::general::__kernel_timespec, + uaddr2: *mut u32, + val3: u32 + ) via SYS_futex -> c::c_long + } + + ret_usize(futex( + uaddr, + op as i32 | flags.bits() as i32, + val, + utime.cast(), + uaddr2, + val3, + ) as isize) + } +} + +#[cfg(linux_kernel)] +#[cfg(all( + target_pointer_width = "32", + not(any(target_arch = "aarch64", target_arch = "x86_64")) +))] +unsafe fn futex_old( + uaddr: *mut u32, + op: FutexOperation, + flags: FutexFlags, + val: u32, + utime: *const Timespec, + uaddr2: *mut u32, + val3: u32, +) -> io::Result<usize> { + syscall! { + fn futex( + uaddr: *mut u32, + futex_op: c::c_int, + val: u32, + timeout: *const linux_raw_sys::general::__kernel_old_timespec, + uaddr2: *mut u32, + val3: u32 + ) via SYS_futex -> c::c_long + } + + let old_utime = linux_raw_sys::general::__kernel_old_timespec { + tv_sec: (*utime).tv_sec.try_into().map_err(|_| io::Errno::INVAL)?, + tv_nsec: (*utime).tv_nsec.try_into().map_err(|_| io::Errno::INVAL)?, + }; + ret_usize(futex( + uaddr, + op as i32 | flags.bits() as i32, + val, + &old_utime, + uaddr2, + val3, + ) as isize) +} |