diff options
Diffstat (limited to 'library/std/src/sys/unix/thread.rs')
| -rw-r--r-- | library/std/src/sys/unix/thread.rs | 46 |
1 files changed, 22 insertions, 24 deletions
diff --git a/library/std/src/sys/unix/thread.rs b/library/std/src/sys/unix/thread.rs index c1d30dd9d..2a1830d06 100644 --- a/library/std/src/sys/unix/thread.rs +++ b/library/std/src/sys/unix/thread.rs @@ -73,7 +73,7 @@ impl Thread { n => { assert_eq!(n, libc::EINVAL); // EINVAL means |stack_size| is either too small or not a - // multiple of the system page size. Because it's definitely + // multiple of the system page size. Because it's definitely // >= PTHREAD_STACK_MIN, it must be an alignment issue. // Round up to the nearest page and try again. let page_size = os::page_size(); @@ -136,7 +136,7 @@ impl Thread { unsafe { // Available since glibc 2.12, musl 1.1.16, and uClibc 1.0.20. - let name = truncate_cstr(name, TASK_COMM_LEN); + let name = truncate_cstr::<{ TASK_COMM_LEN }>(name); let res = libc::pthread_setname_np(libc::pthread_self(), name.as_ptr()); // We have no good way of propagating errors here, but in debug-builds let's check that this actually worked. debug_assert_eq!(res, 0); @@ -153,7 +153,7 @@ impl Thread { #[cfg(any(target_os = "macos", target_os = "ios", target_os = "watchos"))] pub fn set_name(name: &CStr) { unsafe { - let name = truncate_cstr(name, libc::MAXTHREADNAMESIZE); + let name = truncate_cstr::<{ libc::MAXTHREADNAMESIZE }>(name); let res = libc::pthread_setname_np(name.as_ptr()); // We have no good way of propagating errors here, but in debug-builds let's check that this actually worked. debug_assert_eq!(res, 0); @@ -285,17 +285,12 @@ impl Drop for Thread { } #[cfg(any(target_os = "linux", target_os = "macos", target_os = "ios", target_os = "watchos"))] -fn truncate_cstr(cstr: &CStr, max_with_nul: usize) -> crate::borrow::Cow<'_, CStr> { - use crate::{borrow::Cow, ffi::CString}; - - if cstr.to_bytes_with_nul().len() > max_with_nul { - let bytes = cstr.to_bytes()[..max_with_nul - 1].to_vec(); - // SAFETY: the non-nul bytes came straight from a CStr. - // (CString will add the terminating nul.) - Cow::Owned(unsafe { CString::from_vec_unchecked(bytes) }) - } else { - Cow::Borrowed(cstr) +fn truncate_cstr<const MAX_WITH_NUL: usize>(cstr: &CStr) -> [libc::c_char; MAX_WITH_NUL] { + let mut result = [0; MAX_WITH_NUL]; + for (src, dst) in cstr.to_bytes().iter().zip(&mut result[..MAX_WITH_NUL - 1]) { + *dst = *src as libc::c_char; } + result } pub fn available_parallelism() -> io::Result<NonZeroUsize> { @@ -510,7 +505,7 @@ mod cgroups { let limit = raw_quota.next()?; let period = raw_quota.next()?; match (limit.parse::<usize>(), period.parse::<usize>()) { - (Ok(limit), Ok(period)) => { + (Ok(limit), Ok(period)) if period > 0 => { quota = quota.min(limit / period); } _ => {} @@ -570,7 +565,7 @@ mod cgroups { let period = parse_file("cpu.cfs_period_us"); match (limit, period) { - (Some(limit), Some(period)) => quota = quota.min(limit / period), + (Some(limit), Some(period)) if period > 0 => quota = quota.min(limit / period), _ => {} } @@ -658,7 +653,10 @@ pub mod guard { ))] #[cfg_attr(test, allow(dead_code))] pub mod guard { - use libc::{mmap, mprotect}; + #[cfg(not(all(target_os = "linux", target_env = "gnu")))] + use libc::{mmap as mmap64, mprotect}; + #[cfg(all(target_os = "linux", target_env = "gnu"))] + use libc::{mmap64, mprotect}; use libc::{MAP_ANON, MAP_FAILED, MAP_FIXED, MAP_PRIVATE, PROT_NONE, PROT_READ, PROT_WRITE}; use crate::io; @@ -757,10 +755,10 @@ pub mod guard { if cfg!(all(target_os = "linux", not(target_env = "musl"))) { // Linux doesn't allocate the whole stack right away, and // the kernel has its own stack-guard mechanism to fault - // when growing too close to an existing mapping. If we map + // when growing too close to an existing mapping. If we map // our own guard, then the kernel starts enforcing a rather // large gap above that, rendering much of the possible - // stack space useless. See #43052. + // stack space useless. See #43052. // // Instead, we'll just note where we expect rlimit to start // faulting, so our handler can report "stack overflow", and @@ -776,14 +774,14 @@ pub mod guard { None } else if cfg!(target_os = "freebsd") { // FreeBSD's stack autogrows, and optionally includes a guard page - // at the bottom. If we try to remap the bottom of the stack - // ourselves, FreeBSD's guard page moves upwards. So we'll just use + // at the bottom. If we try to remap the bottom of the stack + // ourselves, FreeBSD's guard page moves upwards. So we'll just use // the builtin guard page. let stackptr = get_stack_start_aligned()?; let guardaddr = stackptr.addr(); // Technically the number of guard pages is tunable and controlled // by the security.bsd.stack_guard_page sysctl, but there are - // few reasons to change it from the default. The default value has + // few reasons to change it from the default. The default value has // been 1 ever since FreeBSD 11.1 and 10.4. const GUARD_PAGES: usize = 1; let guard = guardaddr..guardaddr + GUARD_PAGES * page_size; @@ -808,7 +806,7 @@ pub mod guard { // read/write permissions and only then mprotect() it to // no permissions at all. See issue #50313. let stackptr = get_stack_start_aligned()?; - let result = mmap( + let result = mmap64( stackptr, page_size, PROT_READ | PROT_WRITE, @@ -879,9 +877,9 @@ pub mod guard { } else if cfg!(all(target_os = "linux", any(target_env = "gnu", target_env = "uclibc"))) { // glibc used to include the guard area within the stack, as noted in the BUGS - // section of `man pthread_attr_getguardsize`. This has been corrected starting + // section of `man pthread_attr_getguardsize`. This has been corrected starting // with glibc 2.27, and in some distro backports, so the guard is now placed at the - // end (below) the stack. There's no easy way for us to know which we have at + // end (below) the stack. There's no easy way for us to know which we have at // runtime, so we'll just match any fault in the range right above or below the // stack base to call that fault a stack overflow. Some(stackaddr - guardsize..stackaddr + guardsize) |