library/std/src/sys/unix/mod.rs - toolchain/rustc - Git at Google

 #![allow(missing_docs, nonstandard_style)]

 use crate::io::ErrorKind;

 pub use self::rand::hashmap_random_keys;
 pub use libc::strlen;

 #[cfg(not(target_os = "espidf"))]
 #[macro_use]
 pub mod weak;

 pub mod alloc;
 pub mod android;
 pub mod args;
 #[path = "../unix/cmath.rs"]
 pub mod cmath;
 pub mod condvar;
 pub mod env;
 pub mod fd;
 pub mod fs;
 pub mod futex;
 pub mod io;
 #[cfg(any(target_os = "linux", target_os = "android"))]
 pub mod kernel_copy;
 #[cfg(target_os = "l4re")]
 mod l4re;
 pub mod memchr;
 pub mod mutex;
 #[cfg(not(target_os = "l4re"))]
 pub mod net;
 #[cfg(target_os = "l4re")]
 pub use self::l4re::net;
 pub mod os;
 pub mod os_str;
 pub mod path;
 pub mod pipe;
 pub mod process;
 pub mod rand;
 pub mod rwlock;
 pub mod stack_overflow;
 pub mod stdio;
 pub mod thread;
 pub mod thread_local_dtor;
 pub mod thread_local_key;
 pub mod time;

 #[cfg(target_os = "espidf")]
 pub fn init(argc: isize, argv: *const *const u8) {}

 #[cfg(not(target_os = "espidf"))]
 // SAFETY: must be called only once during runtime initialization.
 // NOTE: this is not guaranteed to run, for example when Rust code is called externally.
 pub unsafe fn init(argc: isize, argv: *const *const u8) {
     // The standard streams might be closed on application startup. To prevent
     // std::io::{stdin, stdout,stderr} objects from using other unrelated file
     // resources opened later, we reopen standards streams when they are closed.
     sanitize_standard_fds();

     // By default, some platforms will send a *signal* when an EPIPE error
     // would otherwise be delivered. This runtime doesn't install a SIGPIPE
     // handler, causing it to kill the program, which isn't exactly what we
     // want!
     //
     // Hence, we set SIGPIPE to ignore when the program starts up in order
     // to prevent this problem.
     reset_sigpipe();

     stack_overflow::init();
     args::init(argc, argv);

     unsafe fn sanitize_standard_fds() {
         #[cfg(not(miri))]
         // The standard fds are always available in Miri.
         cfg_if::cfg_if! {
             if #[cfg(not(any(
                 target_os = "emscripten",
                 target_os = "fuchsia",
                 target_os = "vxworks",
                 // The poll on Darwin doesn't set POLLNVAL for closed fds.
                 target_os = "macos",
                 target_os = "ios",
                 target_os = "redox",
             )))] {
                 use crate::sys::os::errno;
                 let pfds: &mut [_] = &mut [
                     libc::pollfd { fd: 0, events: 0, revents: 0 },
                     libc::pollfd { fd: 1, events: 0, revents: 0 },
                     libc::pollfd { fd: 2, events: 0, revents: 0 },
                 ];
                 while libc::poll(pfds.as_mut_ptr(), 3, 0) == -1 {
                     if errno() == libc::EINTR {
                         continue;
                     }
                     libc::abort();
                 }
                 for pfd in pfds {
                     if pfd.revents & libc::POLLNVAL == 0 {
                         continue;
                     }
                     if libc::open("/dev/null\0".as_ptr().cast(), libc::O_RDWR, 0) == -1 {
                         // If the stream is closed but we failed to reopen it, abort the
                         // process. Otherwise we wouldn't preserve the safety of
                         // operations on the corresponding Rust object Stdin, Stdout, or
                         // Stderr.
                         libc::abort();
                     }
                 }
             } else if #[cfg(any(target_os = "macos", target_os = "ios", target_os = "redox"))] {
                 use crate::sys::os::errno;
                 for fd in 0..3 {
                     if libc::fcntl(fd, libc::F_GETFD) == -1 && errno() == libc::EBADF {
                         if libc::open("/dev/null\0".as_ptr().cast(), libc::O_RDWR, 0) == -1 {
                             libc::abort();
                         }
                     }
                 }
             }
         }
     }

     unsafe fn reset_sigpipe() {
         #[cfg(not(any(target_os = "emscripten", target_os = "fuchsia")))]
         assert!(signal(libc::SIGPIPE, libc::SIG_IGN) != libc::SIG_ERR);
     }
 }

 // SAFETY: must be called only once during runtime cleanup.
 // NOTE: this is not guaranteed to run, for example when the program aborts.
 pub unsafe fn cleanup() {
     stack_overflow::cleanup();
 }

 #[cfg(target_os = "android")]
 pub use crate::sys::android::signal;
 #[cfg(not(target_os = "android"))]
 pub use libc::signal;

 pub fn decode_error_kind(errno: i32) -> ErrorKind {
     use ErrorKind::*;
     match errno as libc::c_int {
         libc::E2BIG => ArgumentListTooLong,
         libc::EADDRINUSE => AddrInUse,
         libc::EADDRNOTAVAIL => AddrNotAvailable,
         libc::EBUSY => ResourceBusy,
         libc::ECONNABORTED => ConnectionAborted,
         libc::ECONNREFUSED => ConnectionRefused,
         libc::ECONNRESET => ConnectionReset,
         libc::EDEADLK => Deadlock,
         libc::EDQUOT => FilesystemQuotaExceeded,
         libc::EEXIST => AlreadyExists,
         libc::EFBIG => FileTooLarge,
         libc::EHOSTUNREACH => HostUnreachable,
         libc::EINTR => Interrupted,
         libc::EINVAL => InvalidInput,
         libc::EISDIR => IsADirectory,
         libc::ELOOP => FilesystemLoop,
         libc::ENOENT => NotFound,
         libc::ENOMEM => OutOfMemory,
         libc::ENOSPC => StorageFull,
         libc::ENOSYS => Unsupported,
         libc::EMLINK => TooManyLinks,
         libc::ENAMETOOLONG => FilenameTooLong,
         libc::ENETDOWN => NetworkDown,
         libc::ENETUNREACH => NetworkUnreachable,
         libc::ENOTCONN => NotConnected,
         libc::ENOTDIR => NotADirectory,
         libc::ENOTEMPTY => DirectoryNotEmpty,
         libc::EPIPE => BrokenPipe,
         libc::EROFS => ReadOnlyFilesystem,
         libc::ESPIPE => NotSeekable,
         libc::ESTALE => StaleNetworkFileHandle,
         libc::ETIMEDOUT => TimedOut,
         libc::ETXTBSY => ExecutableFileBusy,
         libc::EXDEV => CrossesDevices,

         libc::EACCES | libc::EPERM => PermissionDenied,

         // These two constants can have the same value on some systems,
         // but different values on others, so we can't use a match
         // clause
         x if x == libc::EAGAIN || x == libc::EWOULDBLOCK => WouldBlock,

         _ => Uncategorized,
     }
 }

 #[doc(hidden)]
 pub trait IsMinusOne {
     fn is_minus_one(&self) -> bool;
 }

 macro_rules! impl_is_minus_one {
     ($($t:ident)*) => ($(impl IsMinusOne for $t {
         fn is_minus_one(&self) -> bool {
             *self == -1
         }
     })*)
 }

 impl_is_minus_one! { i8 i16 i32 i64 isize }

 pub fn cvt<T: IsMinusOne>(t: T) -> crate::io::Result<T> {
     if t.is_minus_one() { Err(crate::io::Error::last_os_error()) } else { Ok(t) }
 }

 pub fn cvt_r<T, F>(mut f: F) -> crate::io::Result<T>
 where
     T: IsMinusOne,
     F: FnMut() -> T,
 {
     loop {
         match cvt(f()) {
             Err(ref e) if e.kind() == ErrorKind::Interrupted => {}
             other => return other,
         }
     }
 }

 pub fn cvt_nz(error: libc::c_int) -> crate::io::Result<()> {
     if error == 0 { Ok(()) } else { Err(crate::io::Error::from_raw_os_error(error)) }
 }

 // libc::abort() will run the SIGABRT handler.  That's fine because anyone who
 // installs a SIGABRT handler already has to expect it to run in Very Bad
 // situations (eg, malloc crashing).
 //
 // Current glibc's abort() function unblocks SIGABRT, raises SIGABRT, clears the
 // SIGABRT handler and raises it again, and then starts to get creative.
 //
 // See the public documentation for `intrinsics::abort()` and `process::abort()`
 // for further discussion.
 //
 // There is confusion about whether libc::abort() flushes stdio streams.
 // libc::abort() is required by ISO C 99 (7.14.1.1p5) to be async-signal-safe,
 // so flushing streams is at least extremely hard, if not entirely impossible.
 //
 // However, some versions of POSIX (eg IEEE Std 1003.1-2001) required abort to
 // do so.  In 1003.1-2004 this was fixed.
 //
 // glibc's implementation did the flush, unsafely, before glibc commit
 // 91e7cf982d01 `abort: Do not flush stdio streams [BZ #15436]' by Florian
 // Weimer.  According to glibc's NEWS:
 //
 //    The abort function terminates the process immediately, without flushing
 //    stdio streams.  Previous glibc versions used to flush streams, resulting
 //    in deadlocks and further data corruption.  This change also affects
 //    process aborts as the result of assertion failures.
 //
 // This is an accurate description of the problem.  The only solution for
 // program with nontrivial use of C stdio is a fixed libc - one which does not
 // try to flush in abort - since even libc-internal errors, and assertion
 // failures generated from C, will go via abort().
 //
 // On systems with old, buggy, libcs, the impact can be severe for a
 // multithreaded C program.  It is much less severe for Rust, because Rust
 // stdlib doesn't use libc stdio buffering.  In a typical Rust program, which
 // does not use C stdio, even a buggy libc::abort() is, in fact, safe.
 pub fn abort_internal() -> ! {
     unsafe { libc::abort() }
 }

 cfg_if::cfg_if! {
     if #[cfg(target_os = "android")] {
         #[link(name = "dl")]
         #[link(name = "log")]
         extern "C" {}
     } else if #[cfg(target_os = "freebsd")] {
         #[link(name = "execinfo")]
         #[link(name = "pthread")]
         extern "C" {}
     } else if #[cfg(target_os = "netbsd")] {
         #[link(name = "pthread")]
         #[link(name = "rt")]
         extern "C" {}
     } else if #[cfg(any(target_os = "dragonfly", target_os = "openbsd"))] {
         #[link(name = "pthread")]
         extern "C" {}
     } else if #[cfg(target_os = "solaris")] {
         #[link(name = "socket")]
         #[link(name = "posix4")]
         #[link(name = "pthread")]
         #[link(name = "resolv")]
         extern "C" {}
     } else if #[cfg(target_os = "illumos")] {
         #[link(name = "socket")]
         #[link(name = "posix4")]
         #[link(name = "pthread")]
         #[link(name = "resolv")]
         #[link(name = "nsl")]
         // Use libumem for the (malloc-compatible) allocator
         #[link(name = "umem")]
         extern "C" {}
     } else if #[cfg(target_os = "macos")] {
         #[link(name = "System")]
         // res_init and friends require -lresolv on macOS/iOS.
         // See #41582 and https://blog.achernya.com/2013/03/os-x-has-silly-libsystem.html
         #[link(name = "resolv")]
         extern "C" {}
     } else if #[cfg(target_os = "ios")] {
         #[link(name = "System")]
         #[link(name = "objc")]
         #[link(name = "Security", kind = "framework")]
         #[link(name = "Foundation", kind = "framework")]
         #[link(name = "resolv")]
         extern "C" {}
     } else if #[cfg(target_os = "fuchsia")] {
         #[link(name = "zircon")]
         #[link(name = "fdio")]
         extern "C" {}
     }
 }

 #[cfg(target_os = "espidf")]
 mod unsupported {
     use crate::io;

     pub fn unsupported<T>() -> io::Result<T> {
         Err(unsupported_err())
     }

     pub fn unsupported_err() -> io::Error {
         io::Error::new_const(
             io::ErrorKind::Unsupported,
             &"operation not supported on this platform",
         )
     }
 }
	#![allow(missing_docs, nonstandard_style)]

	use crate::io::ErrorKind;

	pub use self::rand::hashmap_random_keys;
	pub use libc::strlen;

	#[cfg(not(target_os = "espidf"))]
	#[macro_use]
	pub mod weak;

	pub mod alloc;
	pub mod android;
	pub mod args;
	#[path = "../unix/cmath.rs"]
	pub mod cmath;
	pub mod condvar;
	pub mod env;
	pub mod fd;
	pub mod fs;
	pub mod futex;
	pub mod io;
	#[cfg(any(target_os = "linux", target_os = "android"))]
	pub mod kernel_copy;
	#[cfg(target_os = "l4re")]
	mod l4re;
	pub mod memchr;
	pub mod mutex;
	#[cfg(not(target_os = "l4re"))]
	pub mod net;
	#[cfg(target_os = "l4re")]
	pub use self::l4re::net;
	pub mod os;
	pub mod os_str;
	pub mod path;
	pub mod pipe;
	pub mod process;
	pub mod rand;
	pub mod rwlock;
	pub mod stack_overflow;
	pub mod stdio;
	pub mod thread;
	pub mod thread_local_dtor;
	pub mod thread_local_key;
	pub mod time;

	#[cfg(target_os = "espidf")]
	pub fn init(argc: isize, argv: const const u8) {}

	#[cfg(not(target_os = "espidf"))]
	// SAFETY: must be called only once during runtime initialization.
	// NOTE: this is not guaranteed to run, for example when Rust code is called externally.
	pub unsafe fn init(argc: isize, argv: const const u8) {
	// The standard streams might be closed on application startup. To prevent
	// std::io::{stdin, stdout,stderr} objects from using other unrelated file
	// resources opened later, we reopen standards streams when they are closed.
	sanitize_standard_fds();

	// By default, some platforms will send a signal when an EPIPE error
	// would otherwise be delivered. This runtime doesn't install a SIGPIPE
	// handler, causing it to kill the program, which isn't exactly what we
	// want!
	//
	// Hence, we set SIGPIPE to ignore when the program starts up in order
	// to prevent this problem.
	reset_sigpipe();

	stack_overflow::init();
	args::init(argc, argv);

	unsafe fn sanitize_standard_fds() {
	#[cfg(not(miri))]
	// The standard fds are always available in Miri.
	cfg_if::cfg_if! {
	if #[cfg(not(any(
	target_os = "emscripten",
	target_os = "fuchsia",
	target_os = "vxworks",
	// The poll on Darwin doesn't set POLLNVAL for closed fds.
	target_os = "macos",
	target_os = "ios",
	target_os = "redox",
	)))] {
	use crate::sys::os::errno;
	let pfds: &mut [_] = &mut [
	libc::pollfd { fd: 0, events: 0, revents: 0 },
	libc::pollfd { fd: 1, events: 0, revents: 0 },
	libc::pollfd { fd: 2, events: 0, revents: 0 },
	];
	while libc::poll(pfds.as_mut_ptr(), 3, 0) == -1 {
	if errno() == libc::EINTR {
	continue;
	}
	libc::abort();
	}
	for pfd in pfds {
	if pfd.revents & libc::POLLNVAL == 0 {
	continue;
	}
	if libc::open("/dev/null\0".as_ptr().cast(), libc::O_RDWR, 0) == -1 {
	// If the stream is closed but we failed to reopen it, abort the
	// process. Otherwise we wouldn't preserve the safety of
	// operations on the corresponding Rust object Stdin, Stdout, or
	// Stderr.
	libc::abort();
	}
	}
	} else if #[cfg(any(target_os = "macos", target_os = "ios", target_os = "redox"))] {
	use crate::sys::os::errno;
	for fd in 0..3 {
	if libc::fcntl(fd, libc::F_GETFD) == -1 && errno() == libc::EBADF {
	if libc::open("/dev/null\0".as_ptr().cast(), libc::O_RDWR, 0) == -1 {
	libc::abort();
	}
	}
	}
	}
	}
	}

	unsafe fn reset_sigpipe() {
	#[cfg(not(any(target_os = "emscripten", target_os = "fuchsia")))]
	assert!(signal(libc::SIGPIPE, libc::SIG_IGN) != libc::SIG_ERR);
	}
	}

	// SAFETY: must be called only once during runtime cleanup.
	// NOTE: this is not guaranteed to run, for example when the program aborts.
	pub unsafe fn cleanup() {
	stack_overflow::cleanup();
	}

	#[cfg(target_os = "android")]
	pub use crate::sys::android::signal;
	#[cfg(not(target_os = "android"))]
	pub use libc::signal;

	pub fn decode_error_kind(errno: i32) -> ErrorKind {
	use ErrorKind::*;
	match errno as libc::c_int {
	libc::E2BIG => ArgumentListTooLong,
	libc::EADDRINUSE => AddrInUse,
	libc::EADDRNOTAVAIL => AddrNotAvailable,
	libc::EBUSY => ResourceBusy,
	libc::ECONNABORTED => ConnectionAborted,
	libc::ECONNREFUSED => ConnectionRefused,
	libc::ECONNRESET => ConnectionReset,
	libc::EDEADLK => Deadlock,
	libc::EDQUOT => FilesystemQuotaExceeded,
	libc::EEXIST => AlreadyExists,
	libc::EFBIG => FileTooLarge,
	libc::EHOSTUNREACH => HostUnreachable,
	libc::EINTR => Interrupted,
	libc::EINVAL => InvalidInput,
	libc::EISDIR => IsADirectory,
	libc::ELOOP => FilesystemLoop,
	libc::ENOENT => NotFound,
	libc::ENOMEM => OutOfMemory,
	libc::ENOSPC => StorageFull,
	libc::ENOSYS => Unsupported,
	libc::EMLINK => TooManyLinks,
	libc::ENAMETOOLONG => FilenameTooLong,
	libc::ENETDOWN => NetworkDown,
	libc::ENETUNREACH => NetworkUnreachable,
	libc::ENOTCONN => NotConnected,
	libc::ENOTDIR => NotADirectory,
	libc::ENOTEMPTY => DirectoryNotEmpty,
	libc::EPIPE => BrokenPipe,
	libc::EROFS => ReadOnlyFilesystem,
	libc::ESPIPE => NotSeekable,
	libc::ESTALE => StaleNetworkFileHandle,
	libc::ETIMEDOUT => TimedOut,
	libc::ETXTBSY => ExecutableFileBusy,
	libc::EXDEV => CrossesDevices,

	libc::EACCES \| libc::EPERM => PermissionDenied,

	// These two constants can have the same value on some systems,
	// but different values on others, so we can't use a match
	// clause
	x if x == libc::EAGAIN \|\| x == libc::EWOULDBLOCK => WouldBlock,

	_ => Uncategorized,
	}
	}

	#[doc(hidden)]
	pub trait IsMinusOne {
	fn is_minus_one(&self) -> bool;
	}

	macro_rules! impl_is_minus_one {
	($($t:ident)*) => ($(impl IsMinusOne for $t {
	fn is_minus_one(&self) -> bool {
	*self == -1
	}
	})*)
	}

	impl_is_minus_one! { i8 i16 i32 i64 isize }

	pub fn cvt<T: IsMinusOne>(t: T) -> crate::io::Result<T> {
	if t.is_minus_one() { Err(crate::io::Error::last_os_error()) } else { Ok(t) }
	}

	pub fn cvt_r<T, F>(mut f: F) -> crate::io::Result<T>
	where
	T: IsMinusOne,
	F: FnMut() -> T,
	{
	loop {
	match cvt(f()) {
	Err(ref e) if e.kind() == ErrorKind::Interrupted => {}
	other => return other,
	}
	}
	}

	pub fn cvt_nz(error: libc::c_int) -> crate::io::Result<()> {
	if error == 0 { Ok(()) } else { Err(crate::io::Error::from_raw_os_error(error)) }
	}

	// libc::abort() will run the SIGABRT handler. That's fine because anyone who
	// installs a SIGABRT handler already has to expect it to run in Very Bad
	// situations (eg, malloc crashing).
	//
	// Current glibc's abort() function unblocks SIGABRT, raises SIGABRT, clears the
	// SIGABRT handler and raises it again, and then starts to get creative.
	//
	// See the public documentation for `intrinsics::abort()` and `process::abort()`
	// for further discussion.
	//
	// There is confusion about whether libc::abort() flushes stdio streams.
	// libc::abort() is required by ISO C 99 (7.14.1.1p5) to be async-signal-safe,
	// so flushing streams is at least extremely hard, if not entirely impossible.
	//
	// However, some versions of POSIX (eg IEEE Std 1003.1-2001) required abort to
	// do so. In 1003.1-2004 this was fixed.
	//
	// glibc's implementation did the flush, unsafely, before glibc commit
	// 91e7cf982d01 `abort: Do not flush stdio streams [BZ #15436]' by Florian
	// Weimer. According to glibc's NEWS:
	//
	// The abort function terminates the process immediately, without flushing
	// stdio streams. Previous glibc versions used to flush streams, resulting
	// in deadlocks and further data corruption. This change also affects
	// process aborts as the result of assertion failures.
	//
	// This is an accurate description of the problem. The only solution for
	// program with nontrivial use of C stdio is a fixed libc - one which does not
	// try to flush in abort - since even libc-internal errors, and assertion
	// failures generated from C, will go via abort().
	//
	// On systems with old, buggy, libcs, the impact can be severe for a
	// multithreaded C program. It is much less severe for Rust, because Rust
	// stdlib doesn't use libc stdio buffering. In a typical Rust program, which
	// does not use C stdio, even a buggy libc::abort() is, in fact, safe.
	pub fn abort_internal() -> ! {
	unsafe { libc::abort() }
	}

	cfg_if::cfg_if! {
	if #[cfg(target_os = "android")] {
	#[link(name = "dl")]
	#[link(name = "log")]
	extern "C" {}
	} else if #[cfg(target_os = "freebsd")] {
	#[link(name = "execinfo")]
	#[link(name = "pthread")]
	extern "C" {}
	} else if #[cfg(target_os = "netbsd")] {
	#[link(name = "pthread")]
	#[link(name = "rt")]
	extern "C" {}
	} else if #[cfg(any(target_os = "dragonfly", target_os = "openbsd"))] {
	#[link(name = "pthread")]
	extern "C" {}
	} else if #[cfg(target_os = "solaris")] {
	#[link(name = "socket")]
	#[link(name = "posix4")]
	#[link(name = "pthread")]
	#[link(name = "resolv")]
	extern "C" {}
	} else if #[cfg(target_os = "illumos")] {
	#[link(name = "socket")]
	#[link(name = "posix4")]
	#[link(name = "pthread")]
	#[link(name = "resolv")]
	#[link(name = "nsl")]
	// Use libumem for the (malloc-compatible) allocator
	#[link(name = "umem")]
	extern "C" {}
	} else if #[cfg(target_os = "macos")] {
	#[link(name = "System")]
	// res_init and friends require -lresolv on macOS/iOS.
	// See #41582 and https://blog.achernya.com/2013/03/os-x-has-silly-libsystem.html
	#[link(name = "resolv")]
	extern "C" {}
	} else if #[cfg(target_os = "ios")] {
	#[link(name = "System")]
	#[link(name = "objc")]
	#[link(name = "Security", kind = "framework")]
	#[link(name = "Foundation", kind = "framework")]
	#[link(name = "resolv")]
	extern "C" {}
	} else if #[cfg(target_os = "fuchsia")] {
	#[link(name = "zircon")]
	#[link(name = "fdio")]
	extern "C" {}
	}
	}

	#[cfg(target_os = "espidf")]
	mod unsupported {
	use crate::io;

	pub fn unsupported<T>() -> io::Result<T> {
	Err(unsupported_err())
	}

	pub fn unsupported_err() -> io::Error {
	io::Error::new_const(
	io::ErrorKind::Unsupported,
	&"operation not supported on this platform",
	)
	}
	}