diff options
Diffstat (limited to 'vendor/rustix/src/backend/linux_raw/process/syscalls.rs')
| -rw-r--r-- | vendor/rustix/src/backend/linux_raw/process/syscalls.rs | 603 |
1 files changed, 603 insertions, 0 deletions
diff --git a/vendor/rustix/src/backend/linux_raw/process/syscalls.rs b/vendor/rustix/src/backend/linux_raw/process/syscalls.rs new file mode 100644 index 0000000..bc00af9 --- /dev/null +++ b/vendor/rustix/src/backend/linux_raw/process/syscalls.rs @@ -0,0 +1,603 @@ +//! linux_raw syscalls supporting `rustix::process`. +//! +//! # Safety +//! +//! See the `rustix::backend` module documentation for details. +#![allow(unsafe_code, clippy::undocumented_unsafe_blocks)] + +use super::types::RawCpuSet; +use crate::backend::c; +#[cfg(all(feature = "alloc", feature = "fs"))] +use crate::backend::conv::slice_mut; +use crate::backend::conv::{ + by_mut, by_ref, c_int, c_uint, negative_pid, pass_usize, raw_fd, ret, ret_c_int, + ret_c_int_infallible, ret_c_uint, ret_infallible, ret_owned_fd, ret_usize, size_of, + slice_just_addr, zero, +}; +use crate::fd::{AsRawFd, BorrowedFd, OwnedFd, RawFd}; +#[cfg(feature = "fs")] +use crate::ffi::CStr; +use crate::io; +use crate::pid::RawPid; +use crate::process::{ + Cpuid, MembarrierCommand, MembarrierQuery, Pid, PidfdFlags, PidfdGetfdFlags, Resource, Rlimit, + Uid, WaitId, WaitOptions, WaitStatus, WaitidOptions, WaitidStatus, +}; +use crate::signal::Signal; +use crate::utils::as_mut_ptr; +use core::mem::MaybeUninit; +use core::ptr::{null, null_mut}; +use linux_raw_sys::general::{ + membarrier_cmd, membarrier_cmd_flag, rlimit64, PRIO_PGRP, PRIO_PROCESS, PRIO_USER, + RLIM64_INFINITY, +}; +#[cfg(feature = "fs")] +use {crate::backend::conv::ret_c_uint_infallible, crate::fs::Mode}; +#[cfg(feature = "alloc")] +use {crate::backend::conv::slice_just_addr_mut, crate::process::Gid}; + +// `sched_getcpu` has special optimizations via the vDSO on some architectures. +#[cfg(any( + target_arch = "x86_64", + target_arch = "x86", + target_arch = "riscv64", + target_arch = "powerpc64" +))] +pub(crate) use crate::backend::vdso_wrappers::sched_getcpu; + +// `sched_getcpu` on platforms without a vDSO entry for it. +#[cfg(not(any( + target_arch = "x86_64", + target_arch = "x86", + target_arch = "riscv64", + target_arch = "powerpc64" +)))] +#[inline] +pub(crate) fn sched_getcpu() -> usize { + let mut cpu = MaybeUninit::<u32>::uninit(); + unsafe { + let r = ret(syscall!(__NR_getcpu, &mut cpu, zero(), zero())); + debug_assert!(r.is_ok()); + cpu.assume_init() as usize + } +} + +#[cfg(feature = "fs")] +#[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)) } +} + +#[cfg(feature = "fs")] +#[inline] +pub(crate) fn chroot(filename: &CStr) -> io::Result<()> { + unsafe { ret(syscall_readonly!(__NR_chroot, filename)) } +} + +#[cfg(all(feature = "alloc", feature = "fs"))] +#[inline] +pub(crate) fn getcwd(buf: &mut [MaybeUninit<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) => MembarrierQuery::from_bits_retain(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 getppid() -> Option<Pid> { + unsafe { + let ppid = ret_c_int_infallible(syscall_readonly!(__NR_getppid)); + Pid::from_raw(ppid) + } +} + +#[inline] +pub(crate) fn getpgid(pid: Option<Pid>) -> io::Result<Pid> { + unsafe { + let pgid = ret_c_int(syscall_readonly!(__NR_getpgid, c_int(Pid::as_raw(pid))))?; + debug_assert!(pgid > 0); + Ok(Pid::from_raw_unchecked(pgid)) + } +} + +#[inline] +pub(crate) fn setpgid(pid: Option<Pid>, pgid: Option<Pid>) -> io::Result<()> { + unsafe { + ret(syscall_readonly!( + __NR_setpgid, + c_int(Pid::as_raw(pid)), + c_int(Pid::as_raw(pgid)) + )) + } +} + +#[inline] +pub(crate) fn getpgrp() -> Pid { + // Use the `getpgrp` syscall if available. + #[cfg(not(any(target_arch = "aarch64", target_arch = "riscv64")))] + unsafe { + let pgid = ret_c_int_infallible(syscall_readonly!(__NR_getpgrp)); + debug_assert!(pgid > 0); + Pid::from_raw_unchecked(pgid) + } + + // Otherwise use `getpgrp` and pass it zero. + #[cfg(any(target_arch = "aarch64", target_arch = "riscv64"))] + unsafe { + let pgid = ret_c_int_infallible(syscall_readonly!(__NR_getpgid, c_uint(0))); + debug_assert!(pgid > 0); + Pid::from_raw_unchecked(pgid) + } +} + +#[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_int(Pid::as_raw(pid)), + size_of::<RawCpuSet, _>(), + by_mut(&mut cpuset.bits) + ))?; + let bytes = as_mut_ptr(cpuset).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_int(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(); + } +} + +#[cfg(feature = "fs")] +#[inline] +pub(crate) fn umask(mode: Mode) -> Mode { + unsafe { Mode::from_bits_retain(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 + }) + .clamp(-20, 19); + 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_int(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_int(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_int(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_int(Pid::as_raw(pid)), + c_int(priority) + )) + } +} + +#[inline] +pub(crate) fn getrlimit(limit: Resource) -> Rlimit { + let mut result = MaybeUninit::<rlimit64>::uninit(); + unsafe { + ret_infallible(syscall!( + __NR_prlimit64, + c_uint(0), + limit, + null::<c::c_void>(), + &mut result + )); + rlimit_from_linux(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(err) => Err(err), + } + } +} + +#[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_int(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 } +} + +#[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 waitpgid(pgid: Pid, waitopts: WaitOptions) -> io::Result<Option<(Pid, WaitStatus)>> { + _waitpid(-pgid.as_raw_nonzero().get(), 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_int(syscall!( + __NR_wait4, + c_int(pid as _), + &mut status, + c_int(waitopts.bits() as _), + zero() + ))?; + Ok(Pid::from_raw(pid).map(|pid| (pid, 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::Pgid(pid) => _waitid_pgid(pid, options), + WaitId::PidFd(fd) => _waitid_pidfd(fd, options), + } +} + +#[inline] +fn _waitid_all(options: WaitidOptions) -> io::Result<Option<WaitidStatus>> { + // `waitid` can return successfully without initializing the struct (no + // children found when using `WNOHANG`) + let mut status = MaybeUninit::<c::siginfo_t>::zeroed(); + 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>> { + // `waitid` can return successfully without initializing the struct (no + // children found when using `WNOHANG`) + let mut status = MaybeUninit::<c::siginfo_t>::zeroed(); + unsafe { + ret(syscall!( + __NR_waitid, + c_uint(c::P_PID), + c_int(Pid::as_raw(Some(pid))), + by_mut(&mut status), + c_int(options.bits() as _), + zero() + ))? + }; + + Ok(unsafe { cvt_waitid_status(status) }) +} + +#[inline] +fn _waitid_pgid(pgid: Option<Pid>, options: WaitidOptions) -> io::Result<Option<WaitidStatus>> { + // `waitid` can return successfully without initializing the struct (no + // children found when using `WNOHANG`) + let mut status = MaybeUninit::<c::siginfo_t>::zeroed(); + unsafe { + ret(syscall!( + __NR_waitid, + c_uint(c::P_PGID), + c_int(Pid::as_raw(pgid)), + 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>> { + // `waitid` can return successfully without initializing the struct (no + // children found when using `WNOHANG`) + let mut status = MaybeUninit::<c::siginfo_t>::zeroed(); + 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] +#[rustfmt::skip] +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._sifields._sigchld._pid == 0 { + None + } else { + Some(WaitidStatus(status)) + } +} + +#[inline] +pub(crate) fn getsid(pid: Option<Pid>) -> io::Result<Pid> { + unsafe { + let pid = ret_c_int(syscall_readonly!(__NR_getsid, c_int(Pid::as_raw(pid))))?; + Ok(Pid::from_raw_unchecked(pid)) + } +} + +#[inline] +pub(crate) fn setsid() -> io::Result<Pid> { + unsafe { + let pid = ret_c_int(syscall_readonly!(__NR_setsid))?; + Ok(Pid::from_raw_unchecked(pid)) + } +} + +#[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) fn test_kill_process(pid: Pid) -> io::Result<()> { + unsafe { ret(syscall_readonly!(__NR_kill, pid, pass_usize(0))) } +} + +#[inline] +pub(crate) fn test_kill_process_group(pid: Pid) -> io::Result<()> { + unsafe { + ret(syscall_readonly!( + __NR_kill, + negative_pid(pid), + pass_usize(0) + )) + } +} + +#[inline] +pub(crate) fn test_kill_current_process_group() -> io::Result<()> { + unsafe { ret(syscall_readonly!(__NR_kill, pass_usize(0), pass_usize(0))) } +} + +#[inline] +pub(crate) fn pidfd_getfd( + pidfd: BorrowedFd<'_>, + targetfd: RawFd, + flags: PidfdGetfdFlags, +) -> io::Result<OwnedFd> { + unsafe { + ret_owned_fd(syscall_readonly!( + __NR_pidfd_getfd, + pidfd, + raw_fd(targetfd), + c_int(flags.bits() as _) + )) + } +} + +#[inline] +pub(crate) fn pidfd_open(pid: Pid, flags: PidfdFlags) -> io::Result<OwnedFd> { + unsafe { ret_owned_fd(syscall_readonly!(__NR_pidfd_open, pid, flags)) } +} + +#[cfg(feature = "alloc")] +#[inline] +pub(crate) fn getgroups(buf: &mut [Gid]) -> io::Result<usize> { + let len = buf.len().try_into().map_err(|_| io::Errno::NOMEM)?; + + unsafe { + ret_usize(syscall!( + __NR_getgroups, + c_int(len), + slice_just_addr_mut(buf) + )) + } +} |