diff options
Diffstat (limited to 'vendor/portable-atomic/src/imp/atomic128/detect/auxv.rs')
| -rw-r--r-- | vendor/portable-atomic/src/imp/atomic128/detect/auxv.rs | 727 |
1 files changed, 0 insertions, 727 deletions
diff --git a/vendor/portable-atomic/src/imp/atomic128/detect/auxv.rs b/vendor/portable-atomic/src/imp/atomic128/detect/auxv.rs deleted file mode 100644 index 1be3095..0000000 --- a/vendor/portable-atomic/src/imp/atomic128/detect/auxv.rs +++ /dev/null @@ -1,727 +0,0 @@ -// SPDX-License-Identifier: Apache-2.0 OR MIT - -// Run-time feature detection on aarch64/powerpc64 Linux/Android/FreeBSD by parsing ELF auxiliary vectors. -// -// # Linux/Android -// -// As of nightly-2023-01-23, is_aarch64_feature_detected always uses dlsym by default -// on aarch64 Linux/Android, but on the following platforms, so we can safely assume -// getauxval is linked to the binary. -// -// - On glibc (*-linux-gnu*), [aarch64 support is available on glibc 2.17+](https://sourceware.org/legacy-ml/libc-announce/2012/msg00001.html) -// and is newer than [glibc 2.16 that added getauxval](https://sourceware.org/legacy-ml/libc-announce/2012/msg00000.html). -// - On musl (*-linux-musl*, *-linux-ohos*), [aarch64 support is available on musl 1.1.7+](https://git.musl-libc.org/cgit/musl/tree/WHATSNEW?h=v1.1.7#n1422) -// and is newer than [musl 1.1.0 that added getauxval](https://git.musl-libc.org/cgit/musl/tree/WHATSNEW?h=v1.1.0#n1197). -// https://github.com/rust-lang/rust/commit/9a04ae4997493e9260352064163285cddc43de3c -// - On bionic (*-android*), [64-bit architecture support is available on Android 5.0+ (API level 21+)](https://android-developers.googleblog.com/2014/10/whats-new-in-android-50-lollipop.html) -// and is newer than [Android 4.3 (API level 18) that added getauxval](https://github.com/aosp-mirror/platform_bionic/blob/d3ebc2f7c49a9893b114124d4a6b315f3a328764/libc/include/sys/auxv.h#L49). -// -// However, on musl with static linking, it seems that getauxval is not always available, independent of version requirements: https://github.com/rust-lang/rust/issues/89626 -// (That problem may have been fixed in https://github.com/rust-lang/rust/commit/9a04ae4997493e9260352064163285cddc43de3c, -// but even in the version containing that patch, [there is report](https://github.com/rust-lang/rust/issues/89626#issuecomment-1242636038) -// of the same error.) -// -// On other Linux targets, we cannot assume that getauxval is always available, so we don't enable -// outline-atomics by default (can be enabled by `--cfg portable_atomic_outline_atomics`). -// -// - On musl with static linking. See the above for more. -// Also, in this case, dlsym(getauxval) always returns null. -// - On uClibc-ng (*-linux-uclibc*, *-l4re-uclibc*), [uClibc-ng 1.0.43 (released in 2023-04-05) added getauxval](https://github.com/wbx-github/uclibc-ng/commit/d869bb1600942c01a77539128f9ba5b5b55ad647). -// - On Picolibc, [Picolibc 1.4.6 added getauxval stub](https://github.com/picolibc/picolibc#picolibc-version-146). -// -// See also https://github.com/rust-lang/stdarch/pull/1375 -// -// See tests::test_linux_like and aarch64_aa64reg.rs for (test-only) alternative implementations. -// -// # FreeBSD -// -// As of nightly-2023-01-23, is_aarch64_feature_detected always uses mrs on -// aarch64 FreeBSD. However, they do not work on FreeBSD 12 on QEMU (confirmed -// on FreeBSD 12.{2,3,4}), and we got SIGILL (worked on FreeBSD 13 and 14). -// -// So use elf_aux_info instead of mrs like compiler-rt does. -// https://man.freebsd.org/elf_aux_info(3) -// https://reviews.llvm.org/D109330 -// -// elf_aux_info is available on FreeBSD 12.0+ and 11.4+: -// https://github.com/freebsd/freebsd-src/commit/0b08ae2120cdd08c20a2b806e2fcef4d0a36c470 -// https://github.com/freebsd/freebsd-src/blob/release/11.4.0/sys/sys/auxv.h -// On FreeBSD, [aarch64 support is available on FreeBSD 11.0+](https://www.freebsd.org/releases/11.0R/relnotes/#hardware-arm), -// but FreeBSD 11 (11.4) was EoL on 2021-09-30, and FreeBSD 11.3 was EoL on 2020-09-30: -// https://www.freebsd.org/security/unsupported -// See also https://github.com/rust-lang/stdarch/pull/611#issuecomment-445464613 -// -// See tests::test_freebsd and aarch64_aa64reg.rs for (test-only) alternative implementations. -// -// # PowerPC64 -// -// On PowerPC64, outline-atomics is currently disabled by default mainly for -// compatibility with older versions of operating systems -// (can be enabled by `--cfg portable_atomic_outline_atomics`). - -include!("common.rs"); - -use os::ffi; -#[cfg(any(target_os = "linux", target_os = "android"))] -mod os { - // core::ffi::c_* (except c_void) requires Rust 1.64, libc will soon require Rust 1.47 - #[cfg_attr(test, allow(dead_code))] - pub(super) mod ffi { - pub(crate) use super::super::c_types::c_ulong; - #[cfg(all(target_arch = "aarch64", target_os = "android"))] - pub(crate) use super::super::c_types::{c_char, c_int}; - - extern "C" { - // https://man7.org/linux/man-pages/man3/getauxval.3.html - // https://github.com/bminor/glibc/blob/801af9fafd4689337ebf27260aa115335a0cb2bc/misc/sys/auxv.h - // https://github.com/bminor/musl/blob/7d756e1c04de6eb3f2b3d3e1141a218bb329fcfb/include/sys/auxv.h - // https://github.com/wbx-github/uclibc-ng/blob/cdb07d2cd52af39feb425e6d36c02b30916b9f0a/include/sys/auxv.h - // https://github.com/aosp-mirror/platform_bionic/blob/d3ebc2f7c49a9893b114124d4a6b315f3a328764/libc/include/sys/auxv.h - // https://github.com/picolibc/picolibc/blob/7a8a58aeaa5946cb662577a518051091b691af3a/newlib/libc/picolib/getauxval.c - // https://github.com/rust-lang/libc/blob/0.2.139/src/unix/linux_like/linux/gnu/mod.rs#L1201 - // https://github.com/rust-lang/libc/blob/0.2.139/src/unix/linux_like/linux/musl/mod.rs#L744 - // https://github.com/rust-lang/libc/blob/0.2.139/src/unix/linux_like/android/b64/mod.rs#L333 - pub(crate) fn getauxval(type_: c_ulong) -> c_ulong; - - // Defined in sys/system_properties.h. - // https://github.com/aosp-mirror/platform_bionic/blob/d3ebc2f7c49a9893b114124d4a6b315f3a328764/libc/include/sys/system_properties.h - // https://github.com/rust-lang/libc/blob/0.2.139/src/unix/linux_like/android/mod.rs#L3471 - #[cfg(all(target_arch = "aarch64", target_os = "android"))] - pub(crate) fn __system_property_get(name: *const c_char, value: *mut c_char) -> c_int; - } - - // https://github.com/torvalds/linux/blob/v6.1/include/uapi/linux/auxvec.h - #[cfg(any(test, target_arch = "aarch64"))] - pub(crate) const AT_HWCAP: c_ulong = 16; - #[cfg(any(test, target_arch = "powerpc64"))] - pub(crate) const AT_HWCAP2: c_ulong = 26; - - // Defined in sys/system_properties.h. - // https://github.com/aosp-mirror/platform_bionic/blob/d3ebc2f7c49a9893b114124d4a6b315f3a328764/libc/include/sys/system_properties.h - #[cfg(all(target_arch = "aarch64", target_os = "android"))] - pub(crate) const PROP_VALUE_MAX: c_int = 92; - } - - pub(super) fn getauxval(type_: ffi::c_ulong) -> ffi::c_ulong { - #[cfg(all(target_arch = "aarch64", target_os = "android"))] - { - // Samsung Exynos 9810 has a bug that big and little cores have different - // ISAs. And on older Android (pre-9), the kernel incorrectly reports - // that features available only on some cores are available on all cores. - // https://reviews.llvm.org/D114523 - let mut arch = [0_u8; ffi::PROP_VALUE_MAX as usize]; - // SAFETY: we've passed a valid C string and a buffer with max length. - let len = unsafe { - ffi::__system_property_get( - b"ro.arch\0".as_ptr().cast::<ffi::c_char>(), - arch.as_mut_ptr().cast::<ffi::c_char>(), - ) - }; - // On Exynos, ro.arch is not available on Android 12+, but it is fine - // because Android 9+ includes the fix. - if len > 0 && arch.starts_with(b"exynos9810") { - return 0; - } - } - - // SAFETY: `getauxval` is thread-safe. See also the module level docs. - unsafe { ffi::getauxval(type_) } - } -} -#[cfg(target_os = "freebsd")] -mod os { - // core::ffi::c_* (except c_void) requires Rust 1.64, libc will soon require Rust 1.47 - #[cfg_attr(test, allow(dead_code))] - pub(super) mod ffi { - pub(crate) use super::super::c_types::{c_int, c_ulong, c_void}; - - extern "C" { - // Defined in sys/auxv.h. - // https://man.freebsd.org/elf_aux_info(3) - // https://github.com/freebsd/freebsd-src/blob/deb63adf945d446ed91a9d84124c71f15ae571d1/sys/sys/auxv.h - pub(crate) fn elf_aux_info(aux: c_int, buf: *mut c_void, buf_len: c_int) -> c_int; - } - - // Defined in sys/elf_common.h. - // https://github.com/freebsd/freebsd-src/blob/deb63adf945d446ed91a9d84124c71f15ae571d1/sys/sys/elf_common.h - #[cfg(any(test, target_arch = "aarch64"))] - pub(crate) const AT_HWCAP: c_int = 25; - #[cfg(any(test, target_arch = "powerpc64"))] - pub(crate) const AT_HWCAP2: c_int = 26; - } - - pub(super) fn getauxval(aux: ffi::c_int) -> ffi::c_ulong { - #[allow(clippy::cast_possible_wrap, clippy::cast_possible_truncation)] - const OUT_LEN: ffi::c_int = core::mem::size_of::<ffi::c_ulong>() as ffi::c_int; - let mut out: ffi::c_ulong = 0; - // SAFETY: - // - the pointer is valid because we got it from a reference. - // - `OUT_LEN` is the same as the size of `out`. - // - `elf_aux_info` is thread-safe. - unsafe { - let res = ffi::elf_aux_info( - aux, - (&mut out as *mut ffi::c_ulong).cast::<ffi::c_void>(), - OUT_LEN, - ); - // If elf_aux_info fails, `out` will be left at zero (which is the proper default value). - debug_assert!(res == 0 || out == 0); - } - out - } -} - -// Basically, Linux and FreeBSD use the same hwcap values. -// FreeBSD supports a subset of the hwcap values supported by Linux. -use arch::_detect; -#[cfg(target_arch = "aarch64")] -mod arch { - use super::{ffi, os, CpuInfo}; - - // Linux - // https://github.com/torvalds/linux/blob/1c41041124bd14dd6610da256a3da4e5b74ce6b1/arch/arm64/include/uapi/asm/hwcap.h - // FreeBSD - // Defined in machine/elf.h. - // https://github.com/freebsd/freebsd-src/blob/deb63adf945d446ed91a9d84124c71f15ae571d1/sys/arm64/include/elf.h - // available on FreeBSD 13.0+ and 12.2+ - // https://github.com/freebsd/freebsd-src/blob/release/13.0.0/sys/arm64/include/elf.h - // https://github.com/freebsd/freebsd-src/blob/release/12.2.0/sys/arm64/include/elf.h - pub(super) const HWCAP_ATOMICS: ffi::c_ulong = 1 << 8; - pub(super) const HWCAP_USCAT: ffi::c_ulong = 1 << 25; - #[cfg(any(target_os = "linux", target_os = "android"))] - #[cfg(target_pointer_width = "64")] - #[cfg(test)] - pub(super) const HWCAP2_LRCPC3: ffi::c_ulong = 1 << 46; - #[cfg(any(target_os = "linux", target_os = "android"))] - #[cfg(target_pointer_width = "64")] - #[cfg(test)] - pub(super) const HWCAP2_LSE128: ffi::c_ulong = 1 << 47; - - #[cold] - pub(super) fn _detect(info: &mut CpuInfo) { - let hwcap = os::getauxval(ffi::AT_HWCAP); - - if hwcap & HWCAP_ATOMICS != 0 { - info.set(CpuInfo::HAS_LSE); - } - if hwcap & HWCAP_USCAT != 0 { - info.set(CpuInfo::HAS_LSE2); - } - #[cfg(any(target_os = "linux", target_os = "android"))] - #[cfg(target_pointer_width = "64")] - #[cfg(test)] - { - let hwcap2 = os::getauxval(ffi::AT_HWCAP2); - if hwcap2 & HWCAP2_LRCPC3 != 0 { - info.set(CpuInfo::HAS_RCPC3); - } - if hwcap2 & HWCAP2_LSE128 != 0 { - info.set(CpuInfo::HAS_LSE128); - } - } - } -} -#[cfg(target_arch = "powerpc64")] -mod arch { - use super::{ffi, os, CpuInfo}; - - // Linux - // https://github.com/torvalds/linux/blob/v6.1/arch/powerpc/include/uapi/asm/cputable.h - // FreeBSD - // Defined in machine/cpu.h. - // https://github.com/freebsd/freebsd-src/blob/deb63adf945d446ed91a9d84124c71f15ae571d1/sys/powerpc/include/cpu.h - // available on FreeBSD 11.0+ - // https://github.com/freebsd/freebsd-src/commit/b0bf7fcd298133457991b27625bbed766e612730 - pub(super) const PPC_FEATURE2_ARCH_2_07: ffi::c_ulong = 0x80000000; - - #[cold] - pub(super) fn _detect(info: &mut CpuInfo) { - let hwcap2 = os::getauxval(ffi::AT_HWCAP2); - - // power8 - if hwcap2 & PPC_FEATURE2_ARCH_2_07 != 0 { - info.set(CpuInfo::HAS_QUADWORD_ATOMICS); - } - } -} - -#[allow( - clippy::alloc_instead_of_core, - clippy::std_instead_of_alloc, - clippy::std_instead_of_core, - clippy::undocumented_unsafe_blocks, - clippy::wildcard_imports -)] -#[cfg(test)] -mod tests { - use super::*; - - #[cfg(any(target_os = "linux", target_os = "android"))] - #[cfg(target_pointer_width = "64")] - #[test] - fn test_linux_like() { - use c_types::*; - use core::{arch::asm, mem}; - use std::vec; - use test_helper::{libc, sys}; - - // Linux kernel 6.4 has added a way to read auxv without depending on either libc or mrs trap. - // https://github.com/torvalds/linux/commit/ddc65971bb677aa9f6a4c21f76d3133e106f88eb - // - // This is currently used only for testing. - fn getauxval_pr_get_auxv(type_: ffi::c_ulong) -> Result<ffi::c_ulong, c_int> { - #[cfg(target_arch = "aarch64")] - unsafe fn prctl_get_auxv(out: *mut c_void, len: usize) -> Result<usize, c_int> { - let r: i64; - unsafe { - asm!( - "svc 0", - in("x8") sys::__NR_prctl as u64, - inout("x0") sys::PR_GET_AUXV as u64 => r, - in("x1") ptr_reg!(out), - in("x2") len as u64, - // arg4 and arg5 must be zero. - in("x3") 0_u64, - in("x4") 0_u64, - options(nostack, preserves_flags) - ); - } - #[allow(clippy::cast_possible_truncation, clippy::cast_sign_loss)] - if (r as c_int) < 0 { - Err(r as c_int) - } else { - Ok(r as usize) - } - } - #[cfg(target_arch = "powerpc64")] - unsafe fn prctl_get_auxv(out: *mut c_void, len: usize) -> Result<usize, c_int> { - let r: i64; - unsafe { - asm!( - "sc", - "bns+ 2f", - "neg %r3, %r3", - "2:", - inout("r0") sys::__NR_prctl as u64 => _, - inout("r3") sys::PR_GET_AUXV as u64 => r, - inout("r4") ptr_reg!(out) => _, - inout("r5") len as u64 => _, - // arg4 and arg5 must be zero. - inout("r6") 0_u64 => _, - inout("r7") 0_u64 => _, - out("r8") _, - out("r9") _, - out("r10") _, - out("r11") _, - out("r12") _, - out("cr0") _, - options(nostack, preserves_flags) - ); - } - #[allow(clippy::cast_possible_truncation, clippy::cast_sign_loss)] - if (r as c_int) < 0 { - Err(r as c_int) - } else { - Ok(r as usize) - } - } - - let mut auxv = vec![unsafe { mem::zeroed::<sys::Elf64_auxv_t>() }; 38]; - - let old_len = auxv.len() * mem::size_of::<sys::Elf64_auxv_t>(); - - // SAFETY: - // - `out_len` does not exceed the size of `auxv`. - let _len = unsafe { prctl_get_auxv(auxv.as_mut_ptr().cast::<c_void>(), old_len)? }; - - for aux in &auxv { - if aux.a_type == type_ { - // SAFETY: aux.a_un is #[repr(C)] union and all fields have - // the same size and can be safely transmuted to integers. - return Ok(unsafe { aux.a_un.a_val }); - } - } - Err(0) - } - - unsafe { - let mut u = mem::zeroed(); - assert_eq!(libc::uname(&mut u), 0); - let release = std::ffi::CStr::from_ptr(u.release.as_ptr()); - let release = core::str::from_utf8(release.to_bytes()).unwrap(); - let mut digits = release.split('.'); - let major = digits.next().unwrap().parse::<u32>().unwrap(); - let minor = digits.next().unwrap().parse::<u32>().unwrap(); - if (major, minor) < (6, 4) { - std::eprintln!("kernel version: {major}.{minor} (no pr_get_auxv)"); - assert_eq!(getauxval_pr_get_auxv(ffi::AT_HWCAP).unwrap_err(), -22); - assert_eq!(getauxval_pr_get_auxv(ffi::AT_HWCAP2).unwrap_err(), -22); - } else { - std::eprintln!("kernel version: {major}.{minor} (has pr_get_auxv)"); - assert_eq!( - os::getauxval(ffi::AT_HWCAP), - getauxval_pr_get_auxv(ffi::AT_HWCAP).unwrap() - ); - assert_eq!( - os::getauxval(ffi::AT_HWCAP2), - getauxval_pr_get_auxv(ffi::AT_HWCAP2).unwrap() - ); - } - } - } - - #[allow(clippy::cast_sign_loss)] - #[cfg(all(target_arch = "aarch64", target_os = "android"))] - #[test] - fn test_android() { - unsafe { - let mut arch = [1; ffi::PROP_VALUE_MAX as usize]; - let len = ffi::__system_property_get( - b"ro.arch\0".as_ptr().cast::<ffi::c_char>(), - arch.as_mut_ptr().cast::<ffi::c_char>(), - ); - assert!(len >= 0); - std::eprintln!("len={}", len); - std::eprintln!("arch={:?}", arch); - std::eprintln!( - "arch={:?}", - core::str::from_utf8(core::slice::from_raw_parts(arch.as_ptr(), len as usize)) - .unwrap() - ); - } - } - - #[allow(clippy::cast_possible_wrap)] - #[cfg(target_os = "freebsd")] - #[test] - fn test_freebsd() { - use c_types::*; - use core::{arch::asm, mem, ptr}; - use test_helper::sys; - - // This is almost equivalent to what elf_aux_info does. - // https://man.freebsd.org/elf_aux_info(3) - // On FreeBSD, [aarch64 support is available on FreeBSD 11.0+](https://www.freebsd.org/releases/11.0R/relnotes/#hardware-arm), - // but elf_aux_info is available on FreeBSD 12.0+ and 11.4+: - // https://github.com/freebsd/freebsd-src/commit/0b08ae2120cdd08c20a2b806e2fcef4d0a36c470 - // https://github.com/freebsd/freebsd-src/blob/release/11.4.0/sys/sys/auxv.h - // so use sysctl instead of elf_aux_info. - // Note that FreeBSD 11 (11.4) was EoL on 2021-09-30, and FreeBSD 11.3 was EoL on 2020-09-30: - // https://www.freebsd.org/security/unsupported - // - // std_detect uses this way, but it appears to be somewhat incorrect - // (the type of arg4 of sysctl, auxv is smaller than AT_COUNT, etc.). - // https://github.com/rust-lang/stdarch/blob/a0c30f3e3c75adcd6ee7efc94014ebcead61c507/crates/std_detect/src/detect/os/freebsd/auxvec.rs#L52 - // - // This is currently used only for testing. - // If you want us to use this implementation for compatibility with the older FreeBSD - // version that came to EoL a few years ago, please open an issue. - fn getauxval_sysctl_libc(type_: ffi::c_int) -> ffi::c_ulong { - let mut auxv: [sys::Elf64_Auxinfo; sys::AT_COUNT as usize] = unsafe { mem::zeroed() }; - - let mut len = core::mem::size_of_val(&auxv) as c_size_t; - - // SAFETY: calling getpid is safe. - let pid = unsafe { sys::getpid() }; - let mib = [ - sys::CTL_KERN as c_int, - sys::KERN_PROC as c_int, - sys::KERN_PROC_AUXV as c_int, - pid, - ]; - - #[allow(clippy::cast_possible_truncation)] - // SAFETY: - // - `mib.len()` does not exceed the size of `mib`. - // - `len` does not exceed the size of `auxv`. - // - `sysctl` is thread-safe. - let res = unsafe { - sys::sysctl( - mib.as_ptr(), - mib.len() as c_uint, - auxv.as_mut_ptr().cast::<c_void>(), - &mut len, - ptr::null_mut(), - 0, - ) - }; - - if res != -1 { - for aux in &auxv { - if aux.a_type == type_ as c_long { - // SAFETY: aux.a_un is #[repr(C)] union and all fields have - // the same size and can be safely transmuted to integers. - return unsafe { aux.a_un.a_val as c_ulong }; - } - } - } - 0 - } - // Similar to the above, but call syscall using asm instead of libc. - // Note that FreeBSD does not guarantee the stability of raw syscall as - // much as Linux does (It may actually be stable enough, though: - // https://lists.llvm.org/pipermail/llvm-dev/2019-June/133393.html, - // https://github.com/ziglang/zig/issues/16590). - // - // This is currently used only for testing. - fn getauxval_sysctl_asm_syscall(type_: ffi::c_int) -> Result<ffi::c_ulong, c_int> { - #[allow(non_camel_case_types)] - type pid_t = c_int; - - // https://github.com/freebsd/freebsd-src/blob/9888a79adad22ba06b5aff17d05abac0029c537a/lib/libc/aarch64/SYS.h - // https://github.com/golang/go/blob/4badad8d477ffd7a6b762c35bc69aed82faface7/src/syscall/asm_freebsd_arm64.s - #[cfg(target_arch = "aarch64")] - #[inline] - fn getpid() -> pid_t { - #[allow(clippy::cast_possible_truncation)] - // SAFETY: calling getpid is safe. - unsafe { - let n = sys::SYS_getpid; - let r: i64; - asm!( - "svc 0", - in("x8") n as u64, - out("x0") r, - options(nostack, readonly), - ); - r as pid_t - } - } - #[cfg(target_arch = "aarch64")] - #[inline] - unsafe fn sysctl( - name: *const c_int, - name_len: c_uint, - old_p: *mut c_void, - old_len_p: *mut c_size_t, - new_p: *const c_void, - new_len: c_size_t, - ) -> Result<c_int, c_int> { - #[allow(clippy::cast_possible_truncation)] - // SAFETY: the caller must uphold the safety contract. - unsafe { - let mut n = sys::SYS___sysctl as u64; - let r: i64; - asm!( - "svc 0", - "b.cc 2f", - "mov x8, x0", - "mov x0, #-1", - "2:", - inout("x8") n, - inout("x0") ptr_reg!(name) => r, - inout("x1") name_len as u64 => _, - in("x2") ptr_reg!(old_p), - in("x3") ptr_reg!(old_len_p), - in("x4") ptr_reg!(new_p), - in("x5") new_len as u64, - options(nostack), - ); - if r as c_int == -1 { - Err(n as c_int) - } else { - Ok(r as c_int) - } - } - } - - // https://github.com/freebsd/freebsd-src/blob/9888a79adad22ba06b5aff17d05abac0029c537a/lib/libc/powerpc64/SYS.h - #[cfg(target_arch = "powerpc64")] - #[inline] - fn getpid() -> pid_t { - #[allow(clippy::cast_possible_truncation)] - // SAFETY: calling getpid is safe. - unsafe { - let n = sys::SYS_getpid; - let r: i64; - asm!( - "sc", - inout("r0") n as u64 => _, - out("r3") r, - out("r4") _, - out("r5") _, - out("r6") _, - out("r7") _, - out("r8") _, - out("r9") _, - out("r10") _, - out("r11") _, - out("r12") _, - out("cr0") _, - options(nostack, preserves_flags, readonly), - ); - r as pid_t - } - } - #[cfg(target_arch = "powerpc64")] - #[inline] - unsafe fn sysctl( - name: *const c_int, - name_len: c_uint, - old_p: *mut c_void, - old_len_p: *mut c_size_t, - new_p: *const c_void, - new_len: c_size_t, - ) -> Result<c_int, c_int> { - #[allow(clippy::cast_possible_truncation)] - // SAFETY: the caller must uphold the safety contract. - unsafe { - let mut n = sys::SYS___sysctl as u64; - let r: i64; - asm!( - "sc", - "bns+ 2f", - "mr %r0, %r3", - "li %r3, -1", - "2:", - inout("r0") n, - inout("r3") ptr_reg!(name) => r, - inout("r4") name_len as u64 => _, - inout("r5") ptr_reg!(old_p) => _, - inout("r6") ptr_reg!(old_len_p) => _, - inout("r7") ptr_reg!(new_p) => _, - inout("r8") new_len as u64 => _, - out("r9") _, - out("r10") _, - out("r11") _, - out("r12") _, - out("cr0") _, - options(nostack, preserves_flags) - ); - if r as c_int == -1 { - Err(n as c_int) - } else { - Ok(r as c_int) - } - } - } - - let mut auxv: [sys::Elf64_Auxinfo; sys::AT_COUNT as usize] = unsafe { mem::zeroed() }; - - let mut len = core::mem::size_of_val(&auxv) as c_size_t; - - let pid = getpid(); - let mib = [ - sys::CTL_KERN as c_int, - sys::KERN_PROC as c_int, - sys::KERN_PROC_AUXV as c_int, - pid, - ]; - - #[allow(clippy::cast_possible_truncation)] - // SAFETY: - // - `mib.len()` does not exceed the size of `mib`. - // - `len` does not exceed the size of `auxv`. - // - `sysctl` is thread-safe. - unsafe { - sysctl( - mib.as_ptr(), - mib.len() as c_uint, - auxv.as_mut_ptr().cast::<c_void>(), - &mut len, - ptr::null_mut(), - 0, - )?; - } - - for aux in &auxv { - if aux.a_type == type_ as c_long { - // SAFETY: aux.a_un is #[repr(C)] union and all fields have - // the same size and can be safely transmuted to integers. - return Ok(unsafe { aux.a_un.a_val as c_ulong }); - } - } - Err(0) - } - - assert_eq!(os::getauxval(ffi::AT_HWCAP), getauxval_sysctl_libc(ffi::AT_HWCAP)); - assert_eq!(os::getauxval(ffi::AT_HWCAP2), getauxval_sysctl_libc(ffi::AT_HWCAP2)); - assert_eq!( - os::getauxval(ffi::AT_HWCAP), - getauxval_sysctl_asm_syscall(ffi::AT_HWCAP).unwrap() - ); - assert_eq!( - os::getauxval(ffi::AT_HWCAP2), - // AT_HWCAP2 is only available on FreeBSD 13+, at least for aarch64. - getauxval_sysctl_asm_syscall(ffi::AT_HWCAP2).unwrap_or(0) - ); - } - - // Static assertions for FFI bindings. - // This checks that FFI bindings defined in this crate, FFI bindings defined - // in libc, and FFI bindings generated for the platform's latest header file - // using bindgen have compatible signatures (or the same values if constants). - // Since this is static assertion, we can detect problems with - // `cargo check --tests --target <target>` run in CI (via TESTS=1 build.sh) - // without actually running tests on these platforms. - // See also tools/codegen/src/ffi.rs. - // TODO(codegen): auto-generate this test - #[allow( - clippy::cast_possible_wrap, - clippy::cast_sign_loss, - clippy::cast_possible_truncation, - clippy::no_effect_underscore_binding - )] - const _: fn() = || { - use test_helper::{libc, sys}; - #[cfg(not(target_os = "freebsd"))] - type AtType = ffi::c_ulong; - #[cfg(target_os = "freebsd")] - type AtType = ffi::c_int; - #[cfg(any(target_os = "linux", target_os = "android"))] - { - let mut _getauxval: unsafe extern "C" fn(ffi::c_ulong) -> ffi::c_ulong = ffi::getauxval; - _getauxval = libc::getauxval; - _getauxval = sys::getauxval; - } - #[cfg(all(target_arch = "aarch64", target_os = "android"))] - { - let mut ___system_property_get: unsafe extern "C" fn( - *const ffi::c_char, - *mut ffi::c_char, - ) -> ffi::c_int = ffi::__system_property_get; - ___system_property_get = libc::__system_property_get; - ___system_property_get = sys::__system_property_get; - static_assert!(ffi::PROP_VALUE_MAX == libc::PROP_VALUE_MAX); - static_assert!(ffi::PROP_VALUE_MAX == sys::PROP_VALUE_MAX as ffi::c_int); - } - #[cfg(target_os = "freebsd")] - { - let mut _elf_aux_info: unsafe extern "C" fn( - ffi::c_int, - *mut ffi::c_void, - ffi::c_int, - ) -> ffi::c_int = ffi::elf_aux_info; - _elf_aux_info = libc::elf_aux_info; - _elf_aux_info = sys::elf_aux_info; - } - #[cfg(not(target_os = "freebsd"))] // libc doesn't have this on FreeBSD - static_assert!(ffi::AT_HWCAP == libc::AT_HWCAP); - static_assert!(ffi::AT_HWCAP == sys::AT_HWCAP as AtType); - #[cfg(not(target_os = "freebsd"))] // libc doesn't have this on FreeBSD - static_assert!(ffi::AT_HWCAP2 == libc::AT_HWCAP2); - static_assert!(ffi::AT_HWCAP2 == sys::AT_HWCAP2 as AtType); - #[cfg(target_arch = "aarch64")] - { - // static_assert!(arch::HWCAP_ATOMICS == libc::HWCAP_ATOMICS); // libc doesn't have this - static_assert!(arch::HWCAP_ATOMICS == sys::HWCAP_ATOMICS as ffi::c_ulong); - // static_assert!(HWCAP_USCAT == libc::HWCAP_USCAT); // libc doesn't have this - static_assert!(arch::HWCAP_USCAT == sys::HWCAP_USCAT as ffi::c_ulong); - #[cfg(any(target_os = "linux", target_os = "android"))] - #[cfg(target_pointer_width = "64")] - { - // static_assert!(HWCAP2_LRCPC3 == libc::HWCAP2_LRCPC3); // libc doesn't have this - static_assert!(arch::HWCAP2_LRCPC3 == sys::HWCAP2_LRCPC3 as ffi::c_ulong); - // static_assert!(HWCAP2_LSE128 == libc::HWCAP2_LSE128); // libc doesn't have this - static_assert!(arch::HWCAP2_LSE128 == sys::HWCAP2_LSE128 as ffi::c_ulong); - } - } - #[cfg(target_arch = "powerpc64")] - { - // static_assert!(arch::PPC_FEATURE2_ARCH_2_07 == libc::PPC_FEATURE2_ARCH_2_07); // libc doesn't have this - static_assert!( - arch::PPC_FEATURE2_ARCH_2_07 == sys::PPC_FEATURE2_ARCH_2_07 as ffi::c_ulong - ); - } - }; -} |