diff options
Diffstat (limited to 'library/std/src/sys')
21 files changed, 186 insertions, 58 deletions
diff --git a/library/std/src/sys/net/connection/uefi/mod.rs b/library/std/src/sys/net/connection/uefi/mod.rs index 884cbd4ac1d..16e3487a174 100644 --- a/library/std/src/sys/net/connection/uefi/mod.rs +++ b/library/std/src/sys/net/connection/uefi/mod.rs @@ -86,11 +86,11 @@ impl TcpStream { } pub fn peer_addr(&self) -> io::Result<SocketAddr> { - unsupported() + self.inner.peer_addr() } pub fn socket_addr(&self) -> io::Result<SocketAddr> { - unsupported() + self.inner.socket_addr() } pub fn shutdown(&self, _: Shutdown) -> io::Result<()> { @@ -114,7 +114,7 @@ impl TcpStream { } pub fn nodelay(&self) -> io::Result<bool> { - unsupported() + self.inner.nodelay() } pub fn set_ttl(&self, _: u32) -> io::Result<()> { @@ -122,7 +122,7 @@ impl TcpStream { } pub fn ttl(&self) -> io::Result<u32> { - unsupported() + self.inner.ttl() } pub fn take_error(&self) -> io::Result<Option<io::Error>> { @@ -140,7 +140,9 @@ impl fmt::Debug for TcpStream { } } -pub struct TcpListener(!); +pub struct TcpListener { + inner: tcp::Tcp, +} impl TcpListener { pub fn bind(_: io::Result<&SocketAddr>) -> io::Result<TcpListener> { @@ -148,45 +150,45 @@ impl TcpListener { } pub fn socket_addr(&self) -> io::Result<SocketAddr> { - self.0 + unsupported() } pub fn accept(&self) -> io::Result<(TcpStream, SocketAddr)> { - self.0 + unsupported() } pub fn duplicate(&self) -> io::Result<TcpListener> { - self.0 + unsupported() } pub fn set_ttl(&self, _: u32) -> io::Result<()> { - self.0 + unsupported() } pub fn ttl(&self) -> io::Result<u32> { - self.0 + self.inner.ttl() } pub fn set_only_v6(&self, _: bool) -> io::Result<()> { - self.0 + unsupported() } pub fn only_v6(&self) -> io::Result<bool> { - self.0 + unsupported() } pub fn take_error(&self) -> io::Result<Option<io::Error>> { - self.0 + unsupported() } pub fn set_nonblocking(&self, _: bool) -> io::Result<()> { - self.0 + unsupported() } } impl fmt::Debug for TcpListener { fn fmt(&self, _f: &mut fmt::Formatter<'_>) -> fmt::Result { - self.0 + todo!() } } diff --git a/library/std/src/sys/net/connection/uefi/tcp.rs b/library/std/src/sys/net/connection/uefi/tcp.rs index 1152f69446e..aac97007bbf 100644 --- a/library/std/src/sys/net/connection/uefi/tcp.rs +++ b/library/std/src/sys/net/connection/uefi/tcp.rs @@ -1,6 +1,8 @@ use super::tcp4; use crate::io; use crate::net::SocketAddr; +use crate::ptr::NonNull; +use crate::sys::{helpers, unsupported}; use crate::time::Duration; pub(crate) enum Tcp { @@ -31,4 +33,44 @@ impl Tcp { Self::V4(client) => client.read(buf, timeout), } } + + pub(crate) fn ttl(&self) -> io::Result<u32> { + match self { + Self::V4(client) => client.get_mode_data().map(|x| x.time_to_live.into()), + } + } + + pub(crate) fn nodelay(&self) -> io::Result<bool> { + match self { + Self::V4(client) => { + let temp = client.get_mode_data()?; + match NonNull::new(temp.control_option) { + Some(x) => unsafe { Ok(x.as_ref().enable_nagle.into()) }, + None => unsupported(), + } + } + } + } + + pub fn peer_addr(&self) -> io::Result<SocketAddr> { + match self { + Self::V4(client) => client.get_mode_data().map(|x| { + SocketAddr::new( + helpers::ipv4_from_r_efi(x.access_point.remote_address).into(), + x.access_point.remote_port, + ) + }), + } + } + + pub fn socket_addr(&self) -> io::Result<SocketAddr> { + match self { + Self::V4(client) => client.get_mode_data().map(|x| { + SocketAddr::new( + helpers::ipv4_from_r_efi(x.access_point.station_address).into(), + x.access_point.station_port, + ) + }), + } + } } diff --git a/library/std/src/sys/net/connection/uefi/tcp4.rs b/library/std/src/sys/net/connection/uefi/tcp4.rs index 6342718929a..75862ff247b 100644 --- a/library/std/src/sys/net/connection/uefi/tcp4.rs +++ b/library/std/src/sys/net/connection/uefi/tcp4.rs @@ -67,6 +67,24 @@ impl Tcp4 { if r.is_error() { Err(crate::io::Error::from_raw_os_error(r.as_usize())) } else { Ok(()) } } + pub(crate) fn get_mode_data(&self) -> io::Result<tcp4::ConfigData> { + let mut config_data = tcp4::ConfigData::default(); + let protocol = self.protocol.as_ptr(); + + let r = unsafe { + ((*protocol).get_mode_data)( + protocol, + crate::ptr::null_mut(), + &mut config_data, + crate::ptr::null_mut(), + crate::ptr::null_mut(), + crate::ptr::null_mut(), + ) + }; + + if r.is_error() { Err(io::Error::from_raw_os_error(r.as_usize())) } else { Ok(config_data) } + } + pub(crate) fn connect(&self, timeout: Option<Duration>) -> io::Result<()> { let evt = unsafe { self.create_evt() }?; let completion_token = diff --git a/library/std/src/sys/pal/hermit/thread.rs b/library/std/src/sys/pal/hermit/thread.rs index 9bc5a16b800..95fe4f902d3 100644 --- a/library/std/src/sys/pal/hermit/thread.rs +++ b/library/std/src/sys/pal/hermit/thread.rs @@ -58,7 +58,11 @@ impl Thread { } } - pub unsafe fn new(stack: usize, p: Box<dyn FnOnce()>) -> io::Result<Thread> { + pub unsafe fn new( + stack: usize, + _name: Option<&str>, + p: Box<dyn FnOnce()>, + ) -> io::Result<Thread> { unsafe { Thread::new_with_coreid(stack, p, -1 /* = no specific core */) } diff --git a/library/std/src/sys/pal/itron/thread.rs b/library/std/src/sys/pal/itron/thread.rs index 813e1cbcd58..0d28051fcc4 100644 --- a/library/std/src/sys/pal/itron/thread.rs +++ b/library/std/src/sys/pal/itron/thread.rs @@ -86,7 +86,11 @@ impl Thread { /// # Safety /// /// See `thread::Builder::spawn_unchecked` for safety requirements. - pub unsafe fn new(stack: usize, p: Box<dyn FnOnce()>) -> io::Result<Thread> { + pub unsafe fn new( + stack: usize, + _name: Option<&str>, + p: Box<dyn FnOnce()>, + ) -> io::Result<Thread> { let inner = Box::new(ThreadInner { start: UnsafeCell::new(ManuallyDrop::new(p)), lifecycle: AtomicUsize::new(LIFECYCLE_INIT), diff --git a/library/std/src/sys/pal/sgx/abi/usercalls/mod.rs b/library/std/src/sys/pal/sgx/abi/usercalls/mod.rs index dea44124f45..5041770faf6 100644 --- a/library/std/src/sys/pal/sgx/abi/usercalls/mod.rs +++ b/library/std/src/sys/pal/sgx/abi/usercalls/mod.rs @@ -267,7 +267,7 @@ pub fn send(event_set: u64, tcs: Option<Tcs>) -> IoResult<()> { /// Usercall `insecure_time`. See the ABI documentation for more information. #[unstable(feature = "sgx_platform", issue = "56975")] pub fn insecure_time() -> Duration { - let t = unsafe { raw::insecure_time() }; + let t = unsafe { raw::insecure_time().0 }; Duration::new(t / 1_000_000_000, (t % 1_000_000_000) as _) } diff --git a/library/std/src/sys/pal/sgx/thread.rs b/library/std/src/sys/pal/sgx/thread.rs index 85f6dcd96b4..a236c362706 100644 --- a/library/std/src/sys/pal/sgx/thread.rs +++ b/library/std/src/sys/pal/sgx/thread.rs @@ -96,7 +96,11 @@ pub mod wait_notify { impl Thread { // unsafe: see thread::Builder::spawn_unchecked for safety requirements - pub unsafe fn new(_stack: usize, p: Box<dyn FnOnce() + Send>) -> io::Result<Thread> { + pub unsafe fn new( + _stack: usize, + _name: Option<&str>, + p: Box<dyn FnOnce() + Send>, + ) -> io::Result<Thread> { let mut queue_lock = task_queue::lock(); unsafe { usercalls::launch_thread()? }; let (task, handle) = task_queue::Task::new(p); diff --git a/library/std/src/sys/pal/teeos/thread.rs b/library/std/src/sys/pal/teeos/thread.rs index b9cdc7a2a58..a91d95626e7 100644 --- a/library/std/src/sys/pal/teeos/thread.rs +++ b/library/std/src/sys/pal/teeos/thread.rs @@ -22,7 +22,11 @@ unsafe extern "C" { impl Thread { // unsafe: see thread::Builder::spawn_unchecked for safety requirements - pub unsafe fn new(stack: usize, p: Box<dyn FnOnce()>) -> io::Result<Thread> { + pub unsafe fn new( + stack: usize, + _name: Option<&str>, + p: Box<dyn FnOnce()>, + ) -> io::Result<Thread> { let p = Box::into_raw(Box::new(p)); let mut native: libc::pthread_t = unsafe { mem::zeroed() }; let mut attr: libc::pthread_attr_t = unsafe { mem::zeroed() }; diff --git a/library/std/src/sys/pal/uefi/helpers.rs b/library/std/src/sys/pal/uefi/helpers.rs index 420481648a7..271dc4d11de 100644 --- a/library/std/src/sys/pal/uefi/helpers.rs +++ b/library/std/src/sys/pal/uefi/helpers.rs @@ -761,3 +761,7 @@ impl Drop for OwnedEvent { pub(crate) const fn ipv4_to_r_efi(addr: crate::net::Ipv4Addr) -> efi::Ipv4Address { efi::Ipv4Address { addr: addr.octets() } } + +pub(crate) const fn ipv4_from_r_efi(ip: efi::Ipv4Address) -> crate::net::Ipv4Addr { + crate::net::Ipv4Addr::new(ip.addr[0], ip.addr[1], ip.addr[2], ip.addr[3]) +} diff --git a/library/std/src/sys/pal/uefi/thread.rs b/library/std/src/sys/pal/uefi/thread.rs index e4776ec42fb..75c364362b2 100644 --- a/library/std/src/sys/pal/uefi/thread.rs +++ b/library/std/src/sys/pal/uefi/thread.rs @@ -11,7 +11,11 @@ pub const DEFAULT_MIN_STACK_SIZE: usize = 64 * 1024; impl Thread { // unsafe: see thread::Builder::spawn_unchecked for safety requirements - pub unsafe fn new(_stack: usize, _p: Box<dyn FnOnce()>) -> io::Result<Thread> { + pub unsafe fn new( + _stack: usize, + _name: Option<&str>, + _p: Box<dyn FnOnce()>, + ) -> io::Result<Thread> { unsupported() } diff --git a/library/std/src/sys/pal/unix/os.rs b/library/std/src/sys/pal/unix/os.rs index 850bdfdf5b5..0e68313cc3e 100644 --- a/library/std/src/sys/pal/unix/os.rs +++ b/library/std/src/sys/pal/unix/os.rs @@ -633,7 +633,10 @@ pub fn temp_dir() -> PathBuf { } pub fn home_dir() -> Option<PathBuf> { - return crate::env::var_os("HOME").or_else(|| unsafe { fallback() }).map(PathBuf::from); + return crate::env::var_os("HOME") + .filter(|s| !s.is_empty()) + .or_else(|| unsafe { fallback() }) + .map(PathBuf::from); #[cfg(any( target_os = "android", diff --git a/library/std/src/sys/pal/unix/stack_overflow.rs b/library/std/src/sys/pal/unix/stack_overflow.rs index a3be2cdf738..d89100e6919 100644 --- a/library/std/src/sys/pal/unix/stack_overflow.rs +++ b/library/std/src/sys/pal/unix/stack_overflow.rs @@ -8,8 +8,8 @@ pub struct Handler { } impl Handler { - pub unsafe fn new() -> Handler { - make_handler(false) + pub unsafe fn new(thread_name: Option<Box<str>>) -> Handler { + make_handler(false, thread_name) } fn null() -> Handler { @@ -72,7 +72,6 @@ mod imp { use crate::sync::OnceLock; use crate::sync::atomic::{Atomic, AtomicBool, AtomicPtr, AtomicUsize, Ordering}; use crate::sys::pal::unix::os; - use crate::thread::with_current_name; use crate::{io, mem, panic, ptr}; // Signal handler for the SIGSEGV and SIGBUS handlers. We've got guard pages @@ -158,13 +157,12 @@ mod imp { if !NEED_ALTSTACK.load(Ordering::Relaxed) { // haven't set up our sigaltstack yet NEED_ALTSTACK.store(true, Ordering::Release); - let handler = unsafe { make_handler(true) }; + let handler = unsafe { make_handler(true, None) }; MAIN_ALTSTACK.store(handler.data, Ordering::Relaxed); mem::forget(handler); if let Some(guard_page_range) = guard_page_range.take() { - let thread_name = with_current_name(|name| name.map(Box::from)); - set_current_info(guard_page_range, thread_name); + set_current_info(guard_page_range, Some(Box::from("main"))); } } @@ -230,14 +228,13 @@ mod imp { /// # Safety /// Mutates the alternate signal stack #[forbid(unsafe_op_in_unsafe_fn)] - pub unsafe fn make_handler(main_thread: bool) -> Handler { + pub unsafe fn make_handler(main_thread: bool, thread_name: Option<Box<str>>) -> Handler { if !NEED_ALTSTACK.load(Ordering::Acquire) { return Handler::null(); } if !main_thread { if let Some(guard_page_range) = unsafe { current_guard() } { - let thread_name = with_current_name(|name| name.map(Box::from)); set_current_info(guard_page_range, thread_name); } } @@ -634,7 +631,10 @@ mod imp { pub unsafe fn cleanup() {} - pub unsafe fn make_handler(_main_thread: bool) -> super::Handler { + pub unsafe fn make_handler( + _main_thread: bool, + _thread_name: Option<Box<str>>, + ) -> super::Handler { super::Handler::null() } @@ -717,7 +717,10 @@ mod imp { pub unsafe fn cleanup() {} - pub unsafe fn make_handler(main_thread: bool) -> super::Handler { + pub unsafe fn make_handler( + main_thread: bool, + _thread_name: Option<Box<str>>, + ) -> super::Handler { if !main_thread { reserve_stack(); } diff --git a/library/std/src/sys/pal/unix/thread.rs b/library/std/src/sys/pal/unix/thread.rs index e4f5520d8a3..7f6440152d4 100644 --- a/library/std/src/sys/pal/unix/thread.rs +++ b/library/std/src/sys/pal/unix/thread.rs @@ -22,6 +22,11 @@ pub const DEFAULT_MIN_STACK_SIZE: usize = 256 * 1024; #[cfg(any(target_os = "espidf", target_os = "nuttx"))] pub const DEFAULT_MIN_STACK_SIZE: usize = 0; // 0 indicates that the stack size configured in the ESP-IDF/NuttX menuconfig system should be used +struct ThreadData { + name: Option<Box<str>>, + f: Box<dyn FnOnce()>, +} + pub struct Thread { id: libc::pthread_t, } @@ -34,8 +39,12 @@ unsafe impl Sync for Thread {} impl Thread { // unsafe: see thread::Builder::spawn_unchecked for safety requirements #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces - pub unsafe fn new(stack: usize, p: Box<dyn FnOnce()>) -> io::Result<Thread> { - let p = Box::into_raw(Box::new(p)); + pub unsafe fn new( + stack: usize, + name: Option<&str>, + f: Box<dyn FnOnce()>, + ) -> io::Result<Thread> { + let data = Box::into_raw(Box::new(ThreadData { name: name.map(Box::from), f })); let mut native: libc::pthread_t = mem::zeroed(); let mut attr: mem::MaybeUninit<libc::pthread_attr_t> = mem::MaybeUninit::uninit(); assert_eq!(libc::pthread_attr_init(attr.as_mut_ptr()), 0); @@ -73,7 +82,7 @@ impl Thread { }; } - let ret = libc::pthread_create(&mut native, attr.as_ptr(), thread_start, p as *mut _); + let ret = libc::pthread_create(&mut native, attr.as_ptr(), thread_start, data as *mut _); // Note: if the thread creation fails and this assert fails, then p will // be leaked. However, an alternative design could cause double-free // which is clearly worse. @@ -82,19 +91,20 @@ impl Thread { return if ret != 0 { // The thread failed to start and as a result p was not consumed. Therefore, it is // safe to reconstruct the box so that it gets deallocated. - drop(Box::from_raw(p)); + drop(Box::from_raw(data)); Err(io::Error::from_raw_os_error(ret)) } else { Ok(Thread { id: native }) }; - extern "C" fn thread_start(main: *mut libc::c_void) -> *mut libc::c_void { + extern "C" fn thread_start(data: *mut libc::c_void) -> *mut libc::c_void { unsafe { + let data = Box::from_raw(data as *mut ThreadData); // Next, set up our stack overflow handler which may get triggered if we run // out of stack. - let _handler = stack_overflow::Handler::new(); + let _handler = stack_overflow::Handler::new(data.name); // Finally, let's run some code. - Box::from_raw(main as *mut Box<dyn FnOnce()>)(); + (data.f)(); } ptr::null_mut() } diff --git a/library/std/src/sys/pal/unsupported/thread.rs b/library/std/src/sys/pal/unsupported/thread.rs index 8a3119fa292..5a1e3fde986 100644 --- a/library/std/src/sys/pal/unsupported/thread.rs +++ b/library/std/src/sys/pal/unsupported/thread.rs @@ -10,7 +10,11 @@ pub const DEFAULT_MIN_STACK_SIZE: usize = 64 * 1024; impl Thread { // unsafe: see thread::Builder::spawn_unchecked for safety requirements - pub unsafe fn new(_stack: usize, _p: Box<dyn FnOnce()>) -> io::Result<Thread> { + pub unsafe fn new( + _stack: usize, + _name: Option<&str>, + _p: Box<dyn FnOnce()>, + ) -> io::Result<Thread> { unsupported() } diff --git a/library/std/src/sys/pal/wasi/thread.rs b/library/std/src/sys/pal/wasi/thread.rs index 5f21a553673..a46c74630c9 100644 --- a/library/std/src/sys/pal/wasi/thread.rs +++ b/library/std/src/sys/pal/wasi/thread.rs @@ -73,7 +73,7 @@ impl Thread { // unsafe: see thread::Builder::spawn_unchecked for safety requirements cfg_if::cfg_if! { if #[cfg(target_feature = "atomics")] { - pub unsafe fn new(stack: usize, p: Box<dyn FnOnce()>) -> io::Result<Thread> { + pub unsafe fn new(stack: usize, _name: Option<&str>, p: Box<dyn FnOnce()>) -> io::Result<Thread> { let p = Box::into_raw(Box::new(p)); let mut native: libc::pthread_t = unsafe { mem::zeroed() }; let mut attr: libc::pthread_attr_t = unsafe { mem::zeroed() }; @@ -120,7 +120,7 @@ impl Thread { } } } else { - pub unsafe fn new(_stack: usize, _p: Box<dyn FnOnce()>) -> io::Result<Thread> { + pub unsafe fn new(_stack: usize, _name: Option<&str>, _p: Box<dyn FnOnce()>) -> io::Result<Thread> { crate::sys::unsupported() } } diff --git a/library/std/src/sys/pal/wasm/atomics/thread.rs b/library/std/src/sys/pal/wasm/atomics/thread.rs index 44ce3eab109..ebfabaafc79 100644 --- a/library/std/src/sys/pal/wasm/atomics/thread.rs +++ b/library/std/src/sys/pal/wasm/atomics/thread.rs @@ -10,7 +10,11 @@ pub const DEFAULT_MIN_STACK_SIZE: usize = 1024 * 1024; impl Thread { // unsafe: see thread::Builder::spawn_unchecked for safety requirements - pub unsafe fn new(_stack: usize, _p: Box<dyn FnOnce()>) -> io::Result<Thread> { + pub unsafe fn new( + _stack: usize, + _name: Option<&str>, + _p: Box<dyn FnOnce()>, + ) -> io::Result<Thread> { unsupported() } diff --git a/library/std/src/sys/pal/windows/thread.rs b/library/std/src/sys/pal/windows/thread.rs index 14785171755..b45f76fb546 100644 --- a/library/std/src/sys/pal/windows/thread.rs +++ b/library/std/src/sys/pal/windows/thread.rs @@ -20,7 +20,11 @@ pub struct Thread { impl Thread { // unsafe: see thread::Builder::spawn_unchecked for safety requirements #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces - pub unsafe fn new(stack: usize, p: Box<dyn FnOnce()>) -> io::Result<Thread> { + pub unsafe fn new( + stack: usize, + _name: Option<&str>, + p: Box<dyn FnOnce()>, + ) -> io::Result<Thread> { let p = Box::into_raw(Box::new(p)); // CreateThread rounds up values for the stack size to the nearest page size (at least 4kb). diff --git a/library/std/src/sys/pal/xous/thread.rs b/library/std/src/sys/pal/xous/thread.rs index 1b344e984dc..f2404a62abf 100644 --- a/library/std/src/sys/pal/xous/thread.rs +++ b/library/std/src/sys/pal/xous/thread.rs @@ -20,7 +20,11 @@ pub const GUARD_PAGE_SIZE: usize = 4096; impl Thread { // unsafe: see thread::Builder::spawn_unchecked for safety requirements - pub unsafe fn new(stack: usize, p: Box<dyn FnOnce()>) -> io::Result<Thread> { + pub unsafe fn new( + stack: usize, + _name: Option<&str>, + p: Box<dyn FnOnce()>, + ) -> io::Result<Thread> { let p = Box::into_raw(Box::new(p)); let mut stack_size = crate::cmp::max(stack, MIN_STACK_SIZE); diff --git a/library/std/src/sys/random/sgx.rs b/library/std/src/sys/random/sgx.rs index c3647a8df22..462b19003fa 100644 --- a/library/std/src/sys/random/sgx.rs +++ b/library/std/src/sys/random/sgx.rs @@ -46,22 +46,22 @@ fn rdrand16() -> u16 { } pub fn fill_bytes(bytes: &mut [u8]) { - let mut chunks = bytes.array_chunks_mut(); - for chunk in &mut chunks { + let (chunks, remainder) = bytes.as_chunks_mut(); + for chunk in chunks { *chunk = rdrand64().to_ne_bytes(); } - let mut chunks = chunks.into_remainder().array_chunks_mut(); - for chunk in &mut chunks { + let (chunks, remainder) = remainder.as_chunks_mut(); + for chunk in chunks { *chunk = rdrand32().to_ne_bytes(); } - let mut chunks = chunks.into_remainder().array_chunks_mut(); - for chunk in &mut chunks { + let (chunks, remainder) = remainder.as_chunks_mut(); + for chunk in chunks { *chunk = rdrand16().to_ne_bytes(); } - if let [byte] = chunks.into_remainder() { + if let [byte] = remainder { *byte = rdrand16() as u8; } } diff --git a/library/std/src/sys/random/uefi.rs b/library/std/src/sys/random/uefi.rs index 5f001f0f532..4a71d32fffe 100644 --- a/library/std/src/sys/random/uefi.rs +++ b/library/std/src/sys/random/uefi.rs @@ -138,12 +138,11 @@ mod rdrand { } unsafe fn rdrand_exact(dest: &mut [u8]) -> Option<()> { - let mut chunks = dest.array_chunks_mut(); - for chunk in &mut chunks { + let (chunks, tail) = dest.as_chunks_mut(); + for chunk in chunks { *chunk = unsafe { rdrand() }?.to_ne_bytes(); } - let tail = chunks.into_remainder(); let n = tail.len(); if n > 0 { let src = unsafe { rdrand() }?.to_ne_bytes(); diff --git a/library/std/src/sys/thread_local/guard/windows.rs b/library/std/src/sys/thread_local/guard/windows.rs index b15a0d7c0bd..f747129465d 100644 --- a/library/std/src/sys/thread_local/guard/windows.rs +++ b/library/std/src/sys/thread_local/guard/windows.rs @@ -58,7 +58,7 @@ //! We don't actually use the `/INCLUDE` linker flag here like the article //! mentions because the Rust compiler doesn't propagate linker flags, but //! instead we use a shim function which performs a volatile 1-byte load from -//! the address of the symbol to ensure it sticks around. +//! the address of the _tls_used symbol to ensure it sticks around. //! //! [1]: https://www.codeproject.com/Articles/8113/Thread-Local-Storage-The-C-Way //! [2]: https://github.com/ChromiumWebApps/chromium/blob/master/base/threading/thread_local_storage_win.cc#L42 @@ -68,9 +68,20 @@ use core::ffi::c_void; use crate::ptr; use crate::sys::c; +unsafe extern "C" { + #[link_name = "_tls_used"] + static TLS_USED: u8; +} pub fn enable() { - // When destructors are used, we don't want LLVM eliminating CALLBACK for any - // reason. Once the symbol makes it to the linker, it will do the rest. + // When destructors are used, we need to add a reference to the _tls_used + // symbol provided by the CRT, otherwise the TLS support code will get + // GC'd by the linker and our callback won't be called. + unsafe { ptr::from_ref(&TLS_USED).read_volatile() }; + // We also need to reference CALLBACK to make sure it does not get GC'd + // by the compiler/LLVM. The callback will end up inside the TLS + // callback array pointed to by _TLS_USED through linker shenanigans, + // but as far as the compiler is concerned, it looks like the data is + // unused, so we need this hack to prevent it from disappearing. unsafe { ptr::from_ref(&CALLBACK).read_volatile() }; } |