diff options
Diffstat (limited to 'vendor/rustix-0.37.6/src/backend/linux_raw/process/syscalls.rs')
-rw-r--r-- | vendor/rustix-0.37.6/src/backend/linux_raw/process/syscalls.rs | 661 |
1 files changed, 661 insertions, 0 deletions
diff --git a/vendor/rustix-0.37.6/src/backend/linux_raw/process/syscalls.rs b/vendor/rustix-0.37.6/src/backend/linux_raw/process/syscalls.rs new file mode 100644 index 000000000..f86f8e5b9 --- /dev/null +++ b/vendor/rustix-0.37.6/src/backend/linux_raw/process/syscalls.rs @@ -0,0 +1,661 @@ +//! linux_raw syscalls supporting `rustix::process`. +//! +//! # Safety +//! +//! See the `rustix::backend` module documentation for details. +#![allow(unsafe_code)] +#![allow(clippy::undocumented_unsafe_blocks)] + +use super::super::c; +use super::super::conv::{ + by_mut, by_ref, c_int, c_uint, negative_pid, pass_usize, ret, ret_c_int, ret_c_uint, + ret_infallible, ret_usize, ret_usize_infallible, size_of, slice_just_addr, slice_mut, zero, +}; +use super::types::{RawCpuSet, RawUname}; +use crate::backend::conv::ret_owned_fd; +use crate::fd::{AsRawFd, BorrowedFd, OwnedFd}; +use crate::ffi::CStr; +use crate::io; +use crate::process::{ + Cpuid, Gid, MembarrierCommand, MembarrierQuery, Pid, PidfdFlags, RawNonZeroPid, RawPid, + Resource, Rlimit, Signal, Uid, WaitId, WaitOptions, WaitStatus, WaitidOptions, WaitidStatus, +}; +use core::convert::TryInto; +use core::mem::MaybeUninit; +use core::num::NonZeroU32; +use core::ptr::{null, null_mut}; +use linux_raw_sys::general::{ + __kernel_gid_t, __kernel_pid_t, __kernel_uid_t, membarrier_cmd, membarrier_cmd_flag, rlimit, + rlimit64, PRIO_PGRP, PRIO_PROCESS, PRIO_USER, RLIM64_INFINITY, RLIM_INFINITY, +}; +#[cfg(not(target_os = "wasi"))] +#[cfg(feature = "fs")] +use {super::super::conv::ret_c_uint_infallible, crate::fs::Mode}; + +#[inline] +pub(crate) fn chdir(filename: &CStr) -> io::Result<()> { + unsafe { ret(syscall_readonly!(__NR_chdir, filename)) } +} + +#[inline] +pub(crate) fn fchdir(fd: BorrowedFd<'_>) -> io::Result<()> { + unsafe { ret(syscall_readonly!(__NR_fchdir, fd)) } +} + +#[inline] +pub(crate) fn getcwd(buf: &mut [u8]) -> io::Result<usize> { + let (buf_addr_mut, buf_len) = slice_mut(buf); + unsafe { ret_usize(syscall!(__NR_getcwd, buf_addr_mut, buf_len)) } +} + +#[inline] +pub(crate) fn membarrier_query() -> MembarrierQuery { + unsafe { + match ret_c_uint(syscall!( + __NR_membarrier, + c_int(membarrier_cmd::MEMBARRIER_CMD_QUERY as _), + c_uint(0) + )) { + Ok(query) => { + // SAFETY: The safety of `from_bits_unchecked` is discussed + // [here]. Our "source of truth" is Linux, and here, the + // `query` value is coming from Linux, so we know it only + // contains "source of truth" valid bits. + // + // [here]: https://github.com/bitflags/bitflags/pull/207#issuecomment-671668662 + MembarrierQuery::from_bits_unchecked(query) + } + Err(_) => MembarrierQuery::empty(), + } + } +} + +#[inline] +pub(crate) fn membarrier(cmd: MembarrierCommand) -> io::Result<()> { + unsafe { ret(syscall!(__NR_membarrier, cmd, c_uint(0))) } +} + +#[inline] +pub(crate) fn membarrier_cpu(cmd: MembarrierCommand, cpu: Cpuid) -> io::Result<()> { + unsafe { + ret(syscall!( + __NR_membarrier, + cmd, + c_uint(membarrier_cmd_flag::MEMBARRIER_CMD_FLAG_CPU as _), + cpu + )) + } +} + +#[inline] +pub(crate) fn getpid() -> Pid { + unsafe { + let pid: i32 = ret_usize_infallible(syscall_readonly!(__NR_getpid)) as __kernel_pid_t; + debug_assert!(pid > 0); + Pid::from_raw_nonzero(RawNonZeroPid::new_unchecked(pid as u32)) + } +} + +#[inline] +pub(crate) fn getppid() -> Option<Pid> { + unsafe { + let ppid: i32 = ret_usize_infallible(syscall_readonly!(__NR_getppid)) as __kernel_pid_t; + Pid::from_raw(ppid as u32) + } +} + +#[inline] +pub(crate) fn getpgid(pid: Option<Pid>) -> io::Result<Pid> { + unsafe { + let pgid: i32 = + ret_usize(syscall_readonly!(__NR_getpgid, c_uint(Pid::as_raw(pid))))? as __kernel_pid_t; + Ok(Pid::from_raw_nonzero(NonZeroU32::new_unchecked( + pgid as u32, + ))) + } +} + +#[inline] +pub(crate) fn getpgrp() -> Pid { + // Use the `getpgrp` syscall if available. + #[cfg(not(any(target_arch = "aarch64", target_arch = "riscv64")))] + unsafe { + let pgid: i32 = ret_usize_infallible(syscall_readonly!(__NR_getpgrp)) as __kernel_pid_t; + debug_assert!(pgid > 0); + Pid::from_raw_nonzero(RawNonZeroPid::new_unchecked(pgid as u32)) + } + + // Otherwise use `getpgrp` and pass it zero. + #[cfg(any(target_arch = "aarch64", target_arch = "riscv64"))] + unsafe { + let pgid: i32 = + ret_usize_infallible(syscall_readonly!(__NR_getpgid, c_uint(0))) as __kernel_pid_t; + debug_assert!(pgid > 0); + Pid::from_raw_nonzero(RawNonZeroPid::new_unchecked(pgid as u32)) + } +} + +#[inline] +pub(crate) fn getgid() -> Gid { + #[cfg(any(target_arch = "x86", target_arch = "sparc", target_arch = "arm"))] + unsafe { + let gid: i32 = + (ret_usize_infallible(syscall_readonly!(__NR_getgid32)) as __kernel_gid_t).into(); + Gid::from_raw(gid as u32) + } + #[cfg(not(any(target_arch = "x86", target_arch = "sparc", target_arch = "arm")))] + unsafe { + let gid = ret_usize_infallible(syscall_readonly!(__NR_getgid)) as __kernel_gid_t; + Gid::from_raw(gid as u32) + } +} + +#[inline] +pub(crate) fn getegid() -> Gid { + #[cfg(any(target_arch = "x86", target_arch = "sparc", target_arch = "arm"))] + unsafe { + let gid: i32 = + (ret_usize_infallible(syscall_readonly!(__NR_getegid32)) as __kernel_gid_t).into(); + Gid::from_raw(gid as u32) + } + #[cfg(not(any(target_arch = "x86", target_arch = "sparc", target_arch = "arm")))] + unsafe { + let gid = ret_usize_infallible(syscall_readonly!(__NR_getegid)) as __kernel_gid_t; + Gid::from_raw(gid as u32) + } +} + +#[inline] +pub(crate) fn getuid() -> Uid { + #[cfg(any(target_arch = "x86", target_arch = "sparc", target_arch = "arm"))] + unsafe { + let uid = (ret_usize_infallible(syscall_readonly!(__NR_getuid32)) as __kernel_uid_t).into(); + Uid::from_raw(uid) + } + #[cfg(not(any(target_arch = "x86", target_arch = "sparc", target_arch = "arm")))] + unsafe { + let uid = ret_usize_infallible(syscall_readonly!(__NR_getuid)) as __kernel_uid_t; + Uid::from_raw(uid as u32) + } +} + +#[inline] +pub(crate) fn geteuid() -> Uid { + #[cfg(any(target_arch = "x86", target_arch = "sparc", target_arch = "arm"))] + unsafe { + let uid: i32 = + (ret_usize_infallible(syscall_readonly!(__NR_geteuid32)) as __kernel_uid_t).into(); + Uid::from_raw(uid as u32) + } + #[cfg(not(any(target_arch = "x86", target_arch = "sparc", target_arch = "arm")))] + unsafe { + let uid = ret_usize_infallible(syscall_readonly!(__NR_geteuid)) as __kernel_uid_t; + Uid::from_raw(uid as u32) + } +} + +#[inline] +pub(crate) fn sched_getaffinity(pid: Option<Pid>, cpuset: &mut RawCpuSet) -> io::Result<()> { + unsafe { + // The raw linux syscall returns the size (in bytes) of the `cpumask_t` + // data type that is used internally by the kernel to represent the CPU + // set bit mask. + let size = ret_usize(syscall!( + __NR_sched_getaffinity, + c_uint(Pid::as_raw(pid)), + size_of::<RawCpuSet, _>(), + by_mut(&mut cpuset.bits) + ))?; + let bytes = (cpuset as *mut RawCpuSet).cast::<u8>(); + let rest = bytes.wrapping_add(size); + // Zero every byte in the cpuset not set by the kernel. + rest.write_bytes(0, core::mem::size_of::<RawCpuSet>() - size); + Ok(()) + } +} + +#[inline] +pub(crate) fn sched_setaffinity(pid: Option<Pid>, cpuset: &RawCpuSet) -> io::Result<()> { + unsafe { + ret(syscall_readonly!( + __NR_sched_setaffinity, + c_uint(Pid::as_raw(pid)), + size_of::<RawCpuSet, _>(), + slice_just_addr(&cpuset.bits) + )) + } +} + +#[inline] +pub(crate) fn sched_yield() { + unsafe { + // See the documentation for [`crate::process::sched_yield`] for why + // errors are ignored. + syscall_readonly!(__NR_sched_yield).decode_void(); + } +} + +#[inline] +pub(crate) fn uname() -> RawUname { + let mut uname = MaybeUninit::<RawUname>::uninit(); + unsafe { + ret_infallible(syscall!(__NR_uname, &mut uname)); + uname.assume_init() + } +} + +#[cfg(feature = "fs")] +#[inline] +pub(crate) fn umask(mode: Mode) -> Mode { + unsafe { + // TODO: Use `from_bits_retain` when we switch to bitflags 2.0. + Mode::from_bits_truncate(ret_c_uint_infallible(syscall_readonly!(__NR_umask, mode))) + } +} + +#[inline] +pub(crate) fn nice(inc: i32) -> io::Result<i32> { + let priority = if inc > -40 && inc < 40 { + inc + getpriority_process(None)? + } else { + inc + } + // TODO: With Rust 1.50, use `.clamp` instead of `.min` and `.max`. + //.clamp(-20, 19); + .min(19) + .max(-20); + setpriority_process(None, priority)?; + Ok(priority) +} + +#[inline] +pub(crate) fn getpriority_user(uid: Uid) -> io::Result<i32> { + unsafe { + Ok(20 + - ret_c_int(syscall_readonly!( + __NR_getpriority, + c_uint(PRIO_USER), + c_uint(uid.as_raw()) + ))?) + } +} + +#[inline] +pub(crate) fn getpriority_pgrp(pgid: Option<Pid>) -> io::Result<i32> { + unsafe { + Ok(20 + - ret_c_int(syscall_readonly!( + __NR_getpriority, + c_uint(PRIO_PGRP), + c_uint(Pid::as_raw(pgid)) + ))?) + } +} + +#[inline] +pub(crate) fn getpriority_process(pid: Option<Pid>) -> io::Result<i32> { + unsafe { + Ok(20 + - ret_c_int(syscall_readonly!( + __NR_getpriority, + c_uint(PRIO_PROCESS), + c_uint(Pid::as_raw(pid)) + ))?) + } +} + +#[inline] +pub(crate) fn setpriority_user(uid: Uid, priority: i32) -> io::Result<()> { + unsafe { + ret(syscall_readonly!( + __NR_setpriority, + c_uint(PRIO_USER), + c_uint(uid.as_raw()), + c_int(priority) + )) + } +} + +#[inline] +pub(crate) fn setpriority_pgrp(pgid: Option<Pid>, priority: i32) -> io::Result<()> { + unsafe { + ret(syscall_readonly!( + __NR_setpriority, + c_uint(PRIO_PGRP), + c_uint(Pid::as_raw(pgid)), + c_int(priority) + )) + } +} + +#[inline] +pub(crate) fn setpriority_process(pid: Option<Pid>, priority: i32) -> io::Result<()> { + unsafe { + ret(syscall_readonly!( + __NR_setpriority, + c_uint(PRIO_PROCESS), + c_uint(Pid::as_raw(pid)), + c_int(priority) + )) + } +} + +#[inline] +pub(crate) fn getrlimit(limit: Resource) -> Rlimit { + let mut result = MaybeUninit::<rlimit64>::uninit(); + unsafe { + match ret(syscall!( + __NR_prlimit64, + c_uint(0), + limit, + null::<c::c_void>(), + &mut result + )) { + Ok(()) => rlimit_from_linux(result.assume_init()), + Err(err) => { + debug_assert_eq!(err, io::Errno::NOSYS); + getrlimit_old(limit) + } + } + } +} + +/// The old 32-bit-only `getrlimit` syscall, for when we lack the new +/// `prlimit64`. +unsafe fn getrlimit_old(limit: Resource) -> Rlimit { + let mut result = MaybeUninit::<rlimit>::uninit(); + + // On these platforms, `__NR_getrlimit` is called `__NR_ugetrlimit`. + #[cfg(any( + target_arch = "arm", + target_arch = "powerpc", + target_arch = "powerpc64", + target_arch = "x86", + ))] + { + ret_infallible(syscall!(__NR_ugetrlimit, limit, &mut result)); + } + + // On these platforms, it's just `__NR_getrlimit`. + #[cfg(not(any( + target_arch = "arm", + target_arch = "powerpc", + target_arch = "powerpc64", + target_arch = "x86", + )))] + { + ret_infallible(syscall!(__NR_getrlimit, limit, &mut result)); + } + + rlimit_from_linux_old(result.assume_init()) +} + +#[inline] +pub(crate) fn setrlimit(limit: Resource, new: Rlimit) -> io::Result<()> { + unsafe { + let lim = rlimit_to_linux(new.clone()); + match ret(syscall_readonly!( + __NR_prlimit64, + c_uint(0), + limit, + by_ref(&lim), + null_mut::<c::c_void>() + )) { + Ok(()) => Ok(()), + Err(io::Errno::NOSYS) => setrlimit_old(limit, new), + Err(err) => Err(err), + } + } +} + +/// The old 32-bit-only `setrlimit` syscall, for when we lack the new +/// `prlimit64`. +unsafe fn setrlimit_old(limit: Resource, new: Rlimit) -> io::Result<()> { + let lim = rlimit_to_linux_old(new)?; + ret(syscall_readonly!(__NR_setrlimit, limit, by_ref(&lim))) +} + +#[inline] +pub(crate) fn prlimit(pid: Option<Pid>, limit: Resource, new: Rlimit) -> io::Result<Rlimit> { + let lim = rlimit_to_linux(new); + let mut result = MaybeUninit::<rlimit64>::uninit(); + unsafe { + match ret(syscall!( + __NR_prlimit64, + c_uint(Pid::as_raw(pid)), + limit, + by_ref(&lim), + &mut result + )) { + Ok(()) => Ok(rlimit_from_linux(result.assume_init())), + Err(err) => Err(err), + } + } +} + +/// Convert a Rust [`Rlimit`] to a C `rlimit64`. +#[inline] +fn rlimit_from_linux(lim: rlimit64) -> Rlimit { + let current = if lim.rlim_cur == RLIM64_INFINITY as _ { + None + } else { + Some(lim.rlim_cur) + }; + let maximum = if lim.rlim_max == RLIM64_INFINITY as _ { + None + } else { + Some(lim.rlim_max) + }; + Rlimit { current, maximum } +} + +/// Convert a C `rlimit64` to a Rust `Rlimit`. +#[inline] +fn rlimit_to_linux(lim: Rlimit) -> rlimit64 { + let rlim_cur = match lim.current { + Some(r) => r, + None => RLIM64_INFINITY as _, + }; + let rlim_max = match lim.maximum { + Some(r) => r, + None => RLIM64_INFINITY as _, + }; + rlimit64 { rlim_cur, rlim_max } +} + +/// Like `rlimit_from_linux` but uses Linux's old 32-bit `rlimit`. +#[allow(clippy::useless_conversion)] +fn rlimit_from_linux_old(lim: rlimit) -> Rlimit { + let current = if lim.rlim_cur == RLIM_INFINITY as _ { + None + } else { + Some(lim.rlim_cur.into()) + }; + let maximum = if lim.rlim_max == RLIM_INFINITY as _ { + None + } else { + Some(lim.rlim_max.into()) + }; + Rlimit { current, maximum } +} + +/// Like `rlimit_to_linux` but uses Linux's old 32-bit `rlimit`. +#[allow(clippy::useless_conversion)] +fn rlimit_to_linux_old(lim: Rlimit) -> io::Result<rlimit> { + let rlim_cur = match lim.current { + Some(r) => r.try_into().map_err(|_e| io::Errno::INVAL)?, + None => RLIM_INFINITY as _, + }; + let rlim_max = match lim.maximum { + Some(r) => r.try_into().map_err(|_e| io::Errno::INVAL)?, + None => RLIM_INFINITY as _, + }; + Ok(rlimit { rlim_cur, rlim_max }) +} + +#[inline] +pub(crate) fn wait(waitopts: WaitOptions) -> io::Result<Option<(Pid, WaitStatus)>> { + _waitpid(!0, waitopts) +} + +#[inline] +pub(crate) fn waitpid( + pid: Option<Pid>, + waitopts: WaitOptions, +) -> io::Result<Option<(Pid, WaitStatus)>> { + _waitpid(Pid::as_raw(pid), waitopts) +} + +#[inline] +pub(crate) fn _waitpid( + pid: RawPid, + waitopts: WaitOptions, +) -> io::Result<Option<(Pid, WaitStatus)>> { + unsafe { + let mut status = MaybeUninit::<u32>::uninit(); + let pid = ret_c_uint(syscall!( + __NR_wait4, + c_int(pid as _), + &mut status, + c_int(waitopts.bits() as _), + zero() + ))?; + Ok(RawNonZeroPid::new(pid).map(|non_zero| { + ( + Pid::from_raw_nonzero(non_zero), + WaitStatus::new(status.assume_init()), + ) + })) + } +} + +#[inline] +pub(crate) fn waitid(id: WaitId<'_>, options: WaitidOptions) -> io::Result<Option<WaitidStatus>> { + // Get the id to wait on. + match id { + WaitId::All => _waitid_all(options), + WaitId::Pid(pid) => _waitid_pid(pid, options), + WaitId::PidFd(fd) => _waitid_pidfd(fd, options), + } +} + +#[inline] +fn _waitid_all(options: WaitidOptions) -> io::Result<Option<WaitidStatus>> { + let mut status = MaybeUninit::<c::siginfo_t>::uninit(); + unsafe { + ret(syscall!( + __NR_waitid, + c_uint(c::P_ALL), + c_uint(0), + by_mut(&mut status), + c_int(options.bits() as _), + zero() + ))? + }; + + Ok(unsafe { cvt_waitid_status(status) }) +} + +#[inline] +fn _waitid_pid(pid: Pid, options: WaitidOptions) -> io::Result<Option<WaitidStatus>> { + let mut status = MaybeUninit::<c::siginfo_t>::uninit(); + unsafe { + ret(syscall!( + __NR_waitid, + c_uint(c::P_PID), + c_uint(Pid::as_raw(Some(pid))), + by_mut(&mut status), + c_int(options.bits() as _), + zero() + ))? + }; + + Ok(unsafe { cvt_waitid_status(status) }) +} + +#[inline] +fn _waitid_pidfd(fd: BorrowedFd<'_>, options: WaitidOptions) -> io::Result<Option<WaitidStatus>> { + let mut status = MaybeUninit::<c::siginfo_t>::uninit(); + unsafe { + ret(syscall!( + __NR_waitid, + c_uint(c::P_PIDFD), + c_uint(fd.as_raw_fd() as _), + by_mut(&mut status), + c_int(options.bits() as _), + zero() + ))? + }; + + Ok(unsafe { cvt_waitid_status(status) }) +} + +/// Convert a `siginfo_t` to a `WaitidStatus`. +/// +/// # Safety +/// +/// The caller must ensure that `status` is initialized and that `waitid` +/// returned successfully. +#[inline] +unsafe fn cvt_waitid_status(status: MaybeUninit<c::siginfo_t>) -> Option<WaitidStatus> { + let status = status.assume_init(); + if status.__bindgen_anon_1.__bindgen_anon_1.si_signo == 0 { + None + } else { + Some(WaitidStatus(status)) + } +} + +#[cfg(feature = "runtime")] +#[inline] +pub(crate) fn exit_group(code: c::c_int) -> ! { + unsafe { syscall_noreturn!(__NR_exit_group, c_int(code)) } +} + +#[inline] +pub(crate) fn setsid() -> io::Result<Pid> { + unsafe { + let pid = ret_usize(syscall_readonly!(__NR_setsid))?; + debug_assert!(pid > 0); + Ok(Pid::from_raw_nonzero(RawNonZeroPid::new_unchecked( + pid as u32, + ))) + } +} + +#[inline] +pub(crate) fn kill_process(pid: Pid, sig: Signal) -> io::Result<()> { + unsafe { ret(syscall_readonly!(__NR_kill, pid, sig)) } +} + +#[inline] +pub(crate) fn kill_process_group(pid: Pid, sig: Signal) -> io::Result<()> { + unsafe { ret(syscall_readonly!(__NR_kill, negative_pid(pid), sig)) } +} + +#[inline] +pub(crate) fn kill_current_process_group(sig: Signal) -> io::Result<()> { + unsafe { ret(syscall_readonly!(__NR_kill, pass_usize(0), sig)) } +} + +#[inline] +pub(crate) unsafe fn prctl( + option: c::c_int, + arg2: *mut c::c_void, + arg3: *mut c::c_void, + arg4: *mut c::c_void, + arg5: *mut c::c_void, +) -> io::Result<c::c_int> { + ret_c_int(syscall!(__NR_prctl, c_int(option), arg2, arg3, arg4, arg5)) +} + +#[inline] +pub(crate) fn pidfd_open(pid: Pid, flags: PidfdFlags) -> io::Result<OwnedFd> { + unsafe { + ret_owned_fd(syscall_readonly!( + __NR_pidfd_open, + pid, + c_int(flags.bits() as _) + )) + } +} |