android/vendor/hermit-abi-0.3.1/src/lib.rs - toolchain/sccache - Git at Google

 //! `hermit-abi` is small interface to call functions from the unikernel
 //! [RustyHermit](https://github.com/hermitcore/libhermit-rs).

 #![no_std]
 #![allow(nonstandard_style)]
 #![allow(clippy::missing_safety_doc)]
 #![allow(clippy::result_unit_err)]

 pub mod errno;
 pub mod tcplistener;
 pub mod tcpstream;

 use core::ffi::{c_int, c_void};

 /// A thread handle type
 pub type Tid = u32;

 /// Maximum number of priorities
 pub const NO_PRIORITIES: usize = 31;

 /// Priority of a thread
 #[derive(PartialEq, Eq, PartialOrd, Ord, Debug, Clone, Copy)]
 pub struct Priority(u8);

 impl Priority {
 	pub const fn into(self) -> u8 {
 		self.0
 	}

 	pub const fn from(x: u8) -> Self {
 		Priority(x)
 	}
 }

 pub const HIGH_PRIO: Priority = Priority::from(3);
 pub const NORMAL_PRIO: Priority = Priority::from(2);
 pub const LOW_PRIO: Priority = Priority::from(1);

 /// A handle, identifying a socket
 #[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Default, Hash)]
 pub struct Handle(usize);

 pub const NSEC_PER_SEC: u64 = 1_000_000_000;
 pub const FUTEX_RELATIVE_TIMEOUT: u32 = 1;
 pub const CLOCK_REALTIME: u64 = 1;
 pub const CLOCK_MONOTONIC: u64 = 4;
 pub const STDIN_FILENO: c_int = 0;
 pub const STDOUT_FILENO: c_int = 1;
 pub const STDERR_FILENO: c_int = 2;
 pub const O_RDONLY: i32 = 0o0;
 pub const O_WRONLY: i32 = 0o1;
 pub const O_RDWR: i32 = 0o2;
 pub const O_CREAT: i32 = 0o100;
 pub const O_EXCL: i32 = 0o200;
 pub const O_TRUNC: i32 = 0o1000;
 pub const O_APPEND: i32 = 0o2000;

 /// returns true if file descriptor `fd` is a tty
 pub fn isatty(_fd: c_int) -> bool {
 	false
 }

 /// `timespec` is used by `clock_gettime` to retrieve the
 /// current time
 #[derive(Copy, Clone, Debug)]
 #[repr(C)]
 pub struct timespec {
 	/// seconds
 	pub tv_sec: i64,
 	/// nanoseconds
 	pub tv_nsec: i64,
 }

 /// Internet protocol version.
 #[derive(Debug, Hash, PartialEq, Eq, PartialOrd, Ord, Clone, Copy)]
 pub enum Version {
 	Unspecified,
 	Ipv4,
 	Ipv6,
 }

 /// A four-octet IPv4 address.
 #[derive(Debug, Hash, PartialEq, Eq, PartialOrd, Ord, Clone, Copy, Default)]
 pub struct Ipv4Address(pub [u8; 4]);

 /// A sixteen-octet IPv6 address.
 #[derive(Debug, Hash, PartialEq, Eq, PartialOrd, Ord, Clone, Copy, Default)]
 pub struct Ipv6Address(pub [u8; 16]);

 /// An internetworking address.
 #[derive(Debug, Hash, PartialEq, Eq, PartialOrd, Ord, Clone, Copy)]
 pub enum IpAddress {
 	/// An unspecified address.
 	/// May be used as a placeholder for storage where the address is not assigned yet.
 	Unspecified,
 	/// An IPv4 address.
 	Ipv4(Ipv4Address),
 	/// An IPv6 address.
 	Ipv6(Ipv6Address),
 }

 /// The largest number `rand` will return
 pub const RAND_MAX: u64 = 2_147_483_647;

 pub const AF_INET: i32 = 0;
 pub const AF_INET6: i32 = 1;
 pub const IPPROTO_IP: i32 = 0;
 pub const IPPROTO_IPV6: i32 = 41;
 pub const IPPROTO_UDP: i32 = 17;
 pub const IPPROTO_TCP: i32 = 6;
 pub const IPV6_ADD_MEMBERSHIP: i32 = 12;
 pub const IPV6_DROP_MEMBERSHIP: i32 = 13;
 pub const IPV6_MULTICAST_LOOP: i32 = 19;
 pub const IPV6_V6ONLY: i32 = 27;
 pub const IP_TTL: i32 = 2;
 pub const IP_MULTICAST_TTL: i32 = 5;
 pub const IP_MULTICAST_LOOP: i32 = 7;
 pub const IP_ADD_MEMBERSHIP: i32 = 3;
 pub const IP_DROP_MEMBERSHIP: i32 = 4;
 pub const SHUT_RD: i32 = 0;
 pub const SHUT_WR: i32 = 1;
 pub const SHUT_RDWR: i32 = 2;
 pub const SOCK_DGRAM: i32 = 2;
 pub const SOCK_STREAM: i32 = 1;
 pub const SOL_SOCKET: i32 = 4095;
 pub const SO_BROADCAST: i32 = 32;
 pub const SO_ERROR: i32 = 4103;
 pub const SO_RCVTIMEO: i32 = 4102;
 pub const SO_REUSEADDR: i32 = 4;
 pub const SO_SNDTIMEO: i32 = 4101;
 pub const SO_LINGER: i32 = 128;
 pub const TCP_NODELAY: i32 = 1;
 pub const MSG_PEEK: i32 = 1;
 pub const FIONBIO: i32 = 0x8008667eu32 as i32;
 pub const EAI_NONAME: i32 = -2200;
 pub const EAI_SERVICE: i32 = -2201;
 pub const EAI_FAIL: i32 = -2202;
 pub const EAI_MEMORY: i32 = -2203;
 pub const EAI_FAMILY: i32 = -2204;
 pub const POLLIN: i16 = 0x1;
 pub const POLLPRI: i16 = 0x2;
 pub const POLLOUT: i16 = 0x4;
 pub const POLLERR: i16 = 0x8;
 pub const POLLHUP: i16 = 0x10;
 pub const POLLNVAL: i16 = 0x20;
 pub const POLLRDNORM: i16 = 0x040;
 pub const POLLRDBAND: i16 = 0x080;
 pub const POLLRDHUP: i16 = 0x2000;
 pub type sa_family_t = u8;
 pub type socklen_t = u32;
 pub type in_addr_t = u32;
 pub type in_port_t = u16;
 pub type time_t = i64;
 pub type suseconds_t = i64;
 pub type nfds_t = usize;

 #[repr(C)]
 #[derive(Debug, Copy, Clone)]
 pub struct in_addr {
 	pub s_addr: u32,
 }

 #[repr(C)]
 #[derive(Debug, Copy, Clone)]
 pub struct in6_addr {
 	pub s6_addr: [u8; 16],
 }

 #[repr(C)]
 #[derive(Debug, Copy, Clone)]
 pub struct sockaddr {
 	pub sa_len: u8,
 	pub sa_family: sa_family_t,
 	pub sa_data: [u8; 14],
 }

 #[repr(C)]
 #[derive(Debug, Copy, Clone)]
 pub struct sockaddr_in {
 	pub sin_len: u8,
 	pub sin_family: sa_family_t,
 	pub sin_port: u16,
 	pub sin_addr: in_addr,
 	pub sin_zero: [u8; 8],
 }

 #[repr(C)]
 #[derive(Debug, Copy, Clone)]
 pub struct sockaddr_in6 {
 	pub sin6_family: sa_family_t,
 	pub sin6_port: u16,
 	pub sin6_addr: in6_addr,
 	pub sin6_flowinfo: u32,
 	pub sin6_scope_id: u32,
 }

 #[repr(C)]
 #[derive(Debug, Copy, Clone)]
 pub struct addrinfo {
 	pub ai_flags: i32,
 	pub ai_family: i32,
 	pub ai_socktype: i32,
 	pub ai_protocol: i32,
 	pub ai_addrlen: socklen_t,
 	pub ai_addr: *mut sockaddr,
 	pub ai_canonname: *mut u8,
 	pub ai_next: *mut addrinfo,
 }

 #[repr(C)]
 #[derive(Debug, Copy, Clone)]
 pub struct sockaddr_storage {
 	pub s2_len: u8,
 	pub ss_family: sa_family_t,
 	pub s2_data1: [i8; 2usize],
 	pub s2_data2: [u32; 3usize],
 }

 #[repr(C)]
 #[derive(Debug, Copy, Clone)]
 pub struct ip_mreq {
 	pub imr_multiaddr: in_addr,
 	pub imr_interface: in_addr,
 }

 #[repr(C)]
 #[derive(Debug, Copy, Clone)]
 pub struct ipv6_mreq {
 	pub ipv6mr_multiaddr: in6_addr,
 	pub ipv6mr_interface: u32,
 }

 #[repr(C)]
 #[derive(Debug, Copy, Clone)]
 pub struct linger {
 	pub l_onoff: i32,
 	pub l_linger: i32,
 }

 #[repr(C)]
 #[derive(Debug, Copy, Clone)]
 pub struct timeval {
 	pub tv_sec: time_t,
 	pub tv_usec: suseconds_t,
 }

 #[repr(C)]
 #[derive(Debug, Copy, Clone)]
 pub struct pollfd {
 	pub fd: i32,      /* file descriptor */
 	pub events: i16,  /* events to look for */
 	pub revents: i16, /* events returned */
 }

 // sysmbols, which are part of the library operating system
 extern "C" {
 	/// If the value at address matches the expected value, park the current thread until it is either
 	/// woken up with [`futex_wake`] (returns 0) or an optional timeout elapses (returns -ETIMEDOUT).
 	///
 	/// Setting `timeout` to null means the function will only return if [`futex_wake`] is called.
 	/// Otherwise, `timeout` is interpreted as an absolute time measured with [`CLOCK_MONOTONIC`].
 	/// If [`FUTEX_RELATIVE_TIMEOUT`] is set in `flags` the timeout is understood to be relative
 	/// to the current time.
 	///
 	/// Returns -EINVAL if `address` is null, the timeout is negative or `flags` contains unknown values.
 	#[link_name = "sys_futex_wait"]
 	pub fn futex_wait(
 		address: *mut u32,
 		expected: u32,
 		timeout: *const timespec,
 		flags: u32,
 	) -> i32;

 	/// Wake `count` threads waiting on the futex at `address`. Returns the number of threads
 	/// woken up (saturates to `i32::MAX`). If `count` is `i32::MAX`, wake up all matching
 	/// waiting threads. If `count` is negative or `address` is null, returns -EINVAL.
 	#[link_name = "sys_futex_wake"]
 	pub fn futex_wake(address: *mut u32, count: i32) -> i32;

 	/// sem_init() initializes the unnamed semaphore at the address
 	/// pointed to by `sem`.  The `value` argument specifies the
 	/// initial value for the semaphore.
 	#[link_name = "sys_sem_init"]
 	pub fn sem_init(sem: *mut *const c_void, value: u32) -> i32;

 	/// sem_destroy() frees the unnamed semaphore at the address
 	/// pointed to by `sem`.
 	#[link_name = "sys_sem_destroy"]
 	pub fn sem_destroy(sem: *const c_void) -> i32;

 	/// sem_post() increments the semaphore pointed to by `sem`.
 	/// If the semaphore's value consequently becomes greater
 	/// than zero, then another thread blocked in a sem_wait call
 	/// will be woken up and proceed to lock the semaphore.
 	#[link_name = "sys_sem_post"]
 	pub fn sem_post(sem: *const c_void) -> i32;

 	/// try to decrement a semaphore
 	///
 	/// sem_trywait() is the same as sem_timedwait(), except that
 	/// if the  decrement cannot be immediately performed, then  call
 	/// returns a negative value instead of blocking.
 	#[link_name = "sys_sem_trywait"]
 	pub fn sem_trywait(sem: *const c_void) -> i32;

 	/// decrement a semaphore
 	///
 	/// sem_timedwait() decrements the semaphore pointed to by `sem`.
 	/// If the semaphore's value is greater than zero, then the
 	/// the function returns immediately. If the semaphore currently
 	/// has the value zero, then the call blocks until either
 	/// it becomes possible to perform the decrement of the time limit
 	/// to wait for the semaphore is expired. A time limit `ms` of
 	/// means infinity waiting time.
 	#[link_name = "sys_timedwait"]
 	pub fn sem_timedwait(sem: *const c_void, ms: u32) -> i32;

 	/// Determines the id of the current thread
 	#[link_name = "sys_getpid"]
 	pub fn getpid() -> u32;

 	/// cause normal termination and return `arg`
 	/// to the host system
 	#[link_name = "sys_exit"]
 	pub fn exit(arg: i32) -> !;

 	/// cause abnormal termination
 	#[link_name = "sys_abort"]
 	pub fn abort() -> !;

 	/// suspend execution for microsecond intervals
 	///
 	/// The usleep() function suspends execution of the calling
 	/// thread for (at least) `usecs` microseconds.
 	#[link_name = "sys_usleep"]
 	pub fn usleep(usecs: u64);

 	/// spawn a new thread
 	///
 	/// spawn() starts a new thread. The new thread starts execution
 	/// by invoking `func(usize)`; `arg` is passed as the argument
 	/// to `func`. `prio` defines the priority of the new thread,
 	/// which can be between `LOW_PRIO` and `HIGH_PRIO`.
 	/// `core_id` defines the core, where the thread is located.
 	/// A negative value give the operating system the possibility
 	/// to select the core by its own.
 	#[link_name = "sys_spawn"]
 	pub fn spawn(
 		id: *mut Tid,
 		func: extern "C" fn(usize),
 		arg: usize,
 		prio: u8,
 		core_id: isize,
 	) -> i32;

 	/// spawn a new thread with user-specified stack size
 	///
 	/// spawn2() starts a new thread. The new thread starts execution
 	/// by invoking `func(usize)`; `arg` is passed as the argument
 	/// to `func`. `prio` defines the priority of the new thread,
 	/// which can be between `LOW_PRIO` and `HIGH_PRIO`.
 	/// `core_id` defines the core, where the thread is located.
 	/// A negative value give the operating system the possibility
 	/// to select the core by its own.
 	/// In contrast to spawn(), spawn2() is able to define the
 	/// stack size.
 	#[link_name = "sys_spawn2"]
 	pub fn spawn2(
 		func: extern "C" fn(usize),
 		arg: usize,
 		prio: u8,
 		stack_size: usize,
 		core_id: isize,
 	) -> Tid;

 	/// join with a terminated thread
 	///
 	/// The join() function waits for the thread specified by `id`
 	/// to terminate.
 	#[link_name = "sys_join"]
 	pub fn join(id: Tid) -> i32;

 	/// yield the processor
 	///
 	/// causes the calling thread to relinquish the CPU. The thread
 	/// is moved to the end of the queue for its static priority.
 	#[link_name = "sys_yield"]
 	pub fn yield_now();

 	/// get current time
 	///
 	/// The clock_gettime() functions allow the calling thread
 	/// to retrieve the value used by a clock which is specified
 	/// by `clock_id`.
 	///
 	/// `CLOCK_REALTIME`: the system's real time clock,
 	/// expressed as the amount of time since the Epoch.
 	///
 	/// `CLOCK_MONOTONIC`: clock that increments monotonically,
 	/// tracking the time since an arbitrary point
 	#[link_name = "sys_clock_gettime"]
 	pub fn clock_gettime(clock_id: u64, tp: *mut timespec) -> i32;

 	/// open and possibly create a file
 	///
 	/// The open() system call opens the file specified by `name`.
 	/// If the specified file does not exist, it may optionally
 	/// be created by open().
 	#[link_name = "sys_open"]
 	pub fn open(name: *const i8, flags: i32, mode: i32) -> i32;

 	/// delete the file it refers to `name`
 	#[link_name = "sys_unlink"]
 	pub fn unlink(name: *const i8) -> i32;

 	/// determines the number of activated processors
 	#[link_name = "sys_processor_count"]
 	pub fn get_processor_count() -> usize;

 	#[link_name = "sys_malloc"]
 	pub fn malloc(size: usize, align: usize) -> *mut u8;

 	#[doc(hidden)]
 	#[link_name = "sys_realloc"]
 	pub fn realloc(ptr: *mut u8, size: usize, align: usize, new_size: usize) -> *mut u8;

 	#[doc(hidden)]
 	#[link_name = "sys_free"]
 	pub fn free(ptr: *mut u8, size: usize, align: usize);

 	#[link_name = "sys_notify"]
 	pub fn notify(id: usize, count: i32) -> i32;

 	#[doc(hidden)]
 	#[link_name = "sys_add_queue"]
 	pub fn add_queue(id: usize, timeout_ns: i64) -> i32;

 	#[doc(hidden)]
 	#[link_name = "sys_wait"]
 	pub fn wait(id: usize) -> i32;

 	#[doc(hidden)]
 	#[link_name = "sys_init_queue"]
 	pub fn init_queue(id: usize) -> i32;

 	#[doc(hidden)]
 	#[link_name = "sys_destroy_queue"]
 	pub fn destroy_queue(id: usize) -> i32;

 	/// initialize the network stack
 	#[link_name = "sys_network_init"]
 	pub fn network_init() -> i32;

 	/// Add current task to the queue of blocked tasks. After calling `block_current_task`,
 	/// call `yield_now` to switch to another task.
 	#[link_name = "sys_block_current_task"]
 	pub fn block_current_task();

 	/// Add current task to the queue of blocked tasks, but wake it when `timeout` milliseconds
 	/// have elapsed.
 	///
 	/// After calling `block_current_task`, call `yield_now` to switch to another task.
 	#[link_name = "sys_block_current_task_with_timeout"]
 	pub fn block_current_task_with_timeout(timeout: u64);

 	/// Wakeup task with the thread id `tid`
 	#[link_name = "sys_wakeup_taskt"]
 	pub fn wakeup_task(tid: Tid);

 	#[link_name = "sys_accept"]
 	pub fn accept(s: i32, addr: *mut sockaddr, addrlen: *mut socklen_t) -> i32;

 	/// bind a name to a socket
 	#[link_name = "sys_bind"]
 	pub fn bind(s: i32, name: *const sockaddr, namelen: socklen_t) -> i32;

 	#[link_name = "sys_connect"]
 	pub fn connect(s: i32, name: *const sockaddr, namelen: socklen_t) -> i32;

 	/// read from a file descriptor
 	///
 	/// read() attempts to read `len` bytes of data from the object
 	/// referenced by the descriptor `fd` into the buffer pointed
 	/// to by `buf`.
 	#[link_name = "sys_read"]
 	pub fn read(fd: i32, buf: *mut u8, len: usize) -> isize;

 	/// Fill `len` bytes in `buf` with cryptographically secure random data.
 	///
 	/// Returns either the number of bytes written to buf (a positive value) or
 	/// * `-EINVAL` if `flags` contains unknown flags.
 	/// * `-ENOSYS` if the system does not support random data generation.
 	#[link_name = "sys_read_entropy"]
 	pub fn read_entropy(buf: *mut u8, len: usize, flags: u32) -> isize;

 	/// receive() a message from a socket
 	#[link_name = "sys_recv"]
 	pub fn recv(socket: i32, buf: *mut u8, len: usize, flags: i32) -> isize;

 	/// receive() a message from a socket
 	#[link_name = "sys_recvfrom"]
 	pub fn recvfrom(
 		socket: i32,
 		buf: *mut u8,
 		len: usize,
 		flags: i32,
 		addr: *mut sockaddr,
 		addrlen: *mut socklen_t,
 	) -> isize;

 	/// write to a file descriptor
 	///
 	/// write() attempts to write `len` of data to the object
 	/// referenced by the descriptor `fd` from the
 	/// buffer pointed to by `buf`.
 	#[link_name = "sys_write"]
 	pub fn write(fd: i32, buf: *const u8, len: usize) -> isize;

 	/// close a file descriptor
 	///
 	/// The close() call deletes a file descriptor `fd` from the object
 	/// reference table.
 	#[link_name = "sys_close"]
 	pub fn close(fd: i32) -> i32;

 	/// duplicate an existing file descriptor
 	#[link_name = "sys_dup"]
 	pub fn dup(fd: i32) -> i32;

 	#[link_name = "sys_getpeername"]
 	pub fn getpeername(s: i32, name: *mut sockaddr, namelen: *mut socklen_t) -> i32;

 	#[link_name = "sys_getsockname"]
 	pub fn getsockname(s: i32, name: *mut sockaddr, namelen: *mut socklen_t) -> i32;

 	#[link_name = "sys_getsockopt"]
 	pub fn getsockopt(
 		s: i32,
 		level: i32,
 		optname: i32,
 		optval: *mut c_void,
 		optlen: *mut socklen_t,
 	) -> i32;

 	#[link_name = "sys_setsockopt"]
 	pub fn setsockopt(
 		s: i32,
 		level: i32,
 		optname: i32,
 		optval: *const c_void,
 		optlen: socklen_t,
 	) -> i32;

 	#[link_name = "sys_ioctl"]
 	pub fn ioctl(s: i32, cmd: i32, argp: *mut c_void) -> i32;

 	#[link_name = "sys_pool"]
 	pub fn poll(fds: *mut pollfd, nfds: nfds_t, timeout: i32) -> i32;

 	/// listen for connections on a socket
 	///
 	/// The `backlog` parameter defines the maximum length for the queue of pending
 	/// connections. Currently, the `backlog` must be one.
 	#[link_name = "sys_listen"]
 	pub fn listen(s: i32, backlog: i32) -> i32;

 	#[link_name = "sys_send"]
 	pub fn send(s: i32, mem: *const c_void, len: usize, flags: i32) -> isize;

 	#[link_name = "sys_sendto"]
 	pub fn sendto(
 		s: i32,
 		mem: *const c_void,
 		len: usize,
 		flags: i32,
 		to: *const sockaddr,
 		tolen: socklen_t,
 	) -> isize;

 	/// shut down part of a full-duplex connection
 	#[link_name = "sys_shutdown_socket"]
 	pub fn shutdown_socket(s: i32, how: i32) -> i32;

 	#[link_name = "sys_socket"]
 	pub fn socket(domain: i32, type_: i32, protocol: i32) -> i32;

 	#[link_name = "sys_freeaddrinfo"]
 	pub fn freeaddrinfo(ai: *mut addrinfo);

 	#[link_name = "sys_getaddrinfo"]
 	pub fn getaddrinfo(
 		nodename: *const i8,
 		servname: *const u8,
 		hints: *const addrinfo,
 		res: *mut *mut addrinfo,
 	) -> i32;

 	fn sys_get_priority() -> u8;
 	fn sys_set_priority(tid: Tid, prio: u8);
 }

 /// Determine the priority of the current thread
 #[inline(always)]
 pub unsafe fn get_priority() -> Priority {
 	Priority::from(sys_get_priority())
 }

 /// Determine the priority of the current thread
 #[inline(always)]
 pub unsafe fn set_priority(tid: Tid, prio: Priority) {
 	sys_set_priority(tid, prio.into());
 }
	//! `hermit-abi` is small interface to call functions from the unikernel
	//! [RustyHermit](https://github.com/hermitcore/libhermit-rs).

	#![no_std]
	#![allow(nonstandard_style)]
	#![allow(clippy::missing_safety_doc)]
	#![allow(clippy::result_unit_err)]

	pub mod errno;
	pub mod tcplistener;
	pub mod tcpstream;

	use core::ffi::{c_int, c_void};

	/// A thread handle type
	pub type Tid = u32;

	/// Maximum number of priorities
	pub const NO_PRIORITIES: usize = 31;

	/// Priority of a thread
	#[derive(PartialEq, Eq, PartialOrd, Ord, Debug, Clone, Copy)]
	pub struct Priority(u8);

	impl Priority {
	pub const fn into(self) -> u8 {
	self.0
	}

	pub const fn from(x: u8) -> Self {
	Priority(x)
	}
	}

	pub const HIGH_PRIO: Priority = Priority::from(3);
	pub const NORMAL_PRIO: Priority = Priority::from(2);
	pub const LOW_PRIO: Priority = Priority::from(1);

	/// A handle, identifying a socket
	#[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Default, Hash)]
	pub struct Handle(usize);

	pub const NSEC_PER_SEC: u64 = 1_000_000_000;
	pub const FUTEX_RELATIVE_TIMEOUT: u32 = 1;
	pub const CLOCK_REALTIME: u64 = 1;
	pub const CLOCK_MONOTONIC: u64 = 4;
	pub const STDIN_FILENO: c_int = 0;
	pub const STDOUT_FILENO: c_int = 1;
	pub const STDERR_FILENO: c_int = 2;
	pub const O_RDONLY: i32 = 0o0;
	pub const O_WRONLY: i32 = 0o1;
	pub const O_RDWR: i32 = 0o2;
	pub const O_CREAT: i32 = 0o100;
	pub const O_EXCL: i32 = 0o200;
	pub const O_TRUNC: i32 = 0o1000;
	pub const O_APPEND: i32 = 0o2000;

	/// returns true if file descriptor `fd` is a tty
	pub fn isatty(_fd: c_int) -> bool {
	false
	}

	/// `timespec` is used by `clock_gettime` to retrieve the
	/// current time
	#[derive(Copy, Clone, Debug)]
	#[repr(C)]
	pub struct timespec {
	/// seconds
	pub tv_sec: i64,
	/// nanoseconds
	pub tv_nsec: i64,
	}

	/// Internet protocol version.
	#[derive(Debug, Hash, PartialEq, Eq, PartialOrd, Ord, Clone, Copy)]
	pub enum Version {
	Unspecified,
	Ipv4,
	Ipv6,
	}

	/// A four-octet IPv4 address.
	#[derive(Debug, Hash, PartialEq, Eq, PartialOrd, Ord, Clone, Copy, Default)]
	pub struct Ipv4Address(pub [u8; 4]);

	/// A sixteen-octet IPv6 address.
	#[derive(Debug, Hash, PartialEq, Eq, PartialOrd, Ord, Clone, Copy, Default)]
	pub struct Ipv6Address(pub [u8; 16]);

	/// An internetworking address.
	#[derive(Debug, Hash, PartialEq, Eq, PartialOrd, Ord, Clone, Copy)]
	pub enum IpAddress {
	/// An unspecified address.
	/// May be used as a placeholder for storage where the address is not assigned yet.
	Unspecified,
	/// An IPv4 address.
	Ipv4(Ipv4Address),
	/// An IPv6 address.
	Ipv6(Ipv6Address),
	}

	/// The largest number `rand` will return
	pub const RAND_MAX: u64 = 2_147_483_647;

	pub const AF_INET: i32 = 0;
	pub const AF_INET6: i32 = 1;
	pub const IPPROTO_IP: i32 = 0;
	pub const IPPROTO_IPV6: i32 = 41;
	pub const IPPROTO_UDP: i32 = 17;
	pub const IPPROTO_TCP: i32 = 6;
	pub const IPV6_ADD_MEMBERSHIP: i32 = 12;
	pub const IPV6_DROP_MEMBERSHIP: i32 = 13;
	pub const IPV6_MULTICAST_LOOP: i32 = 19;
	pub const IPV6_V6ONLY: i32 = 27;
	pub const IP_TTL: i32 = 2;
	pub const IP_MULTICAST_TTL: i32 = 5;
	pub const IP_MULTICAST_LOOP: i32 = 7;
	pub const IP_ADD_MEMBERSHIP: i32 = 3;
	pub const IP_DROP_MEMBERSHIP: i32 = 4;
	pub const SHUT_RD: i32 = 0;
	pub const SHUT_WR: i32 = 1;
	pub const SHUT_RDWR: i32 = 2;
	pub const SOCK_DGRAM: i32 = 2;
	pub const SOCK_STREAM: i32 = 1;
	pub const SOL_SOCKET: i32 = 4095;
	pub const SO_BROADCAST: i32 = 32;
	pub const SO_ERROR: i32 = 4103;
	pub const SO_RCVTIMEO: i32 = 4102;
	pub const SO_REUSEADDR: i32 = 4;
	pub const SO_SNDTIMEO: i32 = 4101;
	pub const SO_LINGER: i32 = 128;
	pub const TCP_NODELAY: i32 = 1;
	pub const MSG_PEEK: i32 = 1;
	pub const FIONBIO: i32 = 0x8008667eu32 as i32;
	pub const EAI_NONAME: i32 = -2200;
	pub const EAI_SERVICE: i32 = -2201;
	pub const EAI_FAIL: i32 = -2202;
	pub const EAI_MEMORY: i32 = -2203;
	pub const EAI_FAMILY: i32 = -2204;
	pub const POLLIN: i16 = 0x1;
	pub const POLLPRI: i16 = 0x2;
	pub const POLLOUT: i16 = 0x4;
	pub const POLLERR: i16 = 0x8;
	pub const POLLHUP: i16 = 0x10;
	pub const POLLNVAL: i16 = 0x20;
	pub const POLLRDNORM: i16 = 0x040;
	pub const POLLRDBAND: i16 = 0x080;
	pub const POLLRDHUP: i16 = 0x2000;
	pub type sa_family_t = u8;
	pub type socklen_t = u32;
	pub type in_addr_t = u32;
	pub type in_port_t = u16;
	pub type time_t = i64;
	pub type suseconds_t = i64;
	pub type nfds_t = usize;

	#[repr(C)]
	#[derive(Debug, Copy, Clone)]
	pub struct in_addr {
	pub s_addr: u32,
	}

	#[repr(C)]
	#[derive(Debug, Copy, Clone)]
	pub struct in6_addr {
	pub s6_addr: [u8; 16],
	}

	#[repr(C)]
	#[derive(Debug, Copy, Clone)]
	pub struct sockaddr {
	pub sa_len: u8,
	pub sa_family: sa_family_t,
	pub sa_data: [u8; 14],
	}

	#[repr(C)]
	#[derive(Debug, Copy, Clone)]
	pub struct sockaddr_in {
	pub sin_len: u8,
	pub sin_family: sa_family_t,
	pub sin_port: u16,
	pub sin_addr: in_addr,
	pub sin_zero: [u8; 8],
	}

	#[repr(C)]
	#[derive(Debug, Copy, Clone)]
	pub struct sockaddr_in6 {
	pub sin6_family: sa_family_t,
	pub sin6_port: u16,
	pub sin6_addr: in6_addr,
	pub sin6_flowinfo: u32,
	pub sin6_scope_id: u32,
	}

	#[repr(C)]
	#[derive(Debug, Copy, Clone)]
	pub struct addrinfo {
	pub ai_flags: i32,
	pub ai_family: i32,
	pub ai_socktype: i32,
	pub ai_protocol: i32,
	pub ai_addrlen: socklen_t,
	pub ai_addr: *mut sockaddr,
	pub ai_canonname: *mut u8,
	pub ai_next: *mut addrinfo,
	}

	#[repr(C)]
	#[derive(Debug, Copy, Clone)]
	pub struct sockaddr_storage {
	pub s2_len: u8,
	pub ss_family: sa_family_t,
	pub s2_data1: [i8; 2usize],
	pub s2_data2: [u32; 3usize],
	}

	#[repr(C)]
	#[derive(Debug, Copy, Clone)]
	pub struct ip_mreq {
	pub imr_multiaddr: in_addr,
	pub imr_interface: in_addr,
	}

	#[repr(C)]
	#[derive(Debug, Copy, Clone)]
	pub struct ipv6_mreq {
	pub ipv6mr_multiaddr: in6_addr,
	pub ipv6mr_interface: u32,
	}

	#[repr(C)]
	#[derive(Debug, Copy, Clone)]
	pub struct linger {
	pub l_onoff: i32,
	pub l_linger: i32,
	}

	#[repr(C)]
	#[derive(Debug, Copy, Clone)]
	pub struct timeval {
	pub tv_sec: time_t,
	pub tv_usec: suseconds_t,
	}

	#[repr(C)]
	#[derive(Debug, Copy, Clone)]
	pub struct pollfd {
	pub fd: i32, /* file descriptor */
	pub events: i16, /* events to look for */
	pub revents: i16, /* events returned */
	}

	// sysmbols, which are part of the library operating system
	extern "C" {
	/// If the value at address matches the expected value, park the current thread until it is either
	/// woken up with [`futex_wake`] (returns 0) or an optional timeout elapses (returns -ETIMEDOUT).
	///
	/// Setting `timeout` to null means the function will only return if [`futex_wake`] is called.
	/// Otherwise, `timeout` is interpreted as an absolute time measured with [`CLOCK_MONOTONIC`].
	/// If [`FUTEX_RELATIVE_TIMEOUT`] is set in `flags` the timeout is understood to be relative
	/// to the current time.
	///
	/// Returns -EINVAL if `address` is null, the timeout is negative or `flags` contains unknown values.
	#[link_name = "sys_futex_wait"]
	pub fn futex_wait(
	address: *mut u32,
	expected: u32,
	timeout: *const timespec,
	flags: u32,
	) -> i32;

	/// Wake `count` threads waiting on the futex at `address`. Returns the number of threads
	/// woken up (saturates to `i32::MAX`). If `count` is `i32::MAX`, wake up all matching
	/// waiting threads. If `count` is negative or `address` is null, returns -EINVAL.
	#[link_name = "sys_futex_wake"]
	pub fn futex_wake(address: *mut u32, count: i32) -> i32;

	/// sem_init() initializes the unnamed semaphore at the address
	/// pointed to by `sem`. The `value` argument specifies the
	/// initial value for the semaphore.
	#[link_name = "sys_sem_init"]
	pub fn sem_init(sem: mut const c_void, value: u32) -> i32;

	/// sem_destroy() frees the unnamed semaphore at the address
	/// pointed to by `sem`.
	#[link_name = "sys_sem_destroy"]
	pub fn sem_destroy(sem: *const c_void) -> i32;

	/// sem_post() increments the semaphore pointed to by `sem`.
	/// If the semaphore's value consequently becomes greater
	/// than zero, then another thread blocked in a sem_wait call
	/// will be woken up and proceed to lock the semaphore.
	#[link_name = "sys_sem_post"]
	pub fn sem_post(sem: *const c_void) -> i32;

	/// try to decrement a semaphore
	///
	/// sem_trywait() is the same as sem_timedwait(), except that
	/// if the decrement cannot be immediately performed, then call
	/// returns a negative value instead of blocking.
	#[link_name = "sys_sem_trywait"]
	pub fn sem_trywait(sem: *const c_void) -> i32;

	/// decrement a semaphore
	///
	/// sem_timedwait() decrements the semaphore pointed to by `sem`.
	/// If the semaphore's value is greater than zero, then the
	/// the function returns immediately. If the semaphore currently
	/// has the value zero, then the call blocks until either
	/// it becomes possible to perform the decrement of the time limit
	/// to wait for the semaphore is expired. A time limit `ms` of
	/// means infinity waiting time.
	#[link_name = "sys_timedwait"]
	pub fn sem_timedwait(sem: *const c_void, ms: u32) -> i32;

	/// Determines the id of the current thread
	#[link_name = "sys_getpid"]
	pub fn getpid() -> u32;

	/// cause normal termination and return `arg`
	/// to the host system
	#[link_name = "sys_exit"]
	pub fn exit(arg: i32) -> !;

	/// cause abnormal termination
	#[link_name = "sys_abort"]
	pub fn abort() -> !;

	/// suspend execution for microsecond intervals
	///
	/// The usleep() function suspends execution of the calling
	/// thread for (at least) `usecs` microseconds.
	#[link_name = "sys_usleep"]
	pub fn usleep(usecs: u64);

	/// spawn a new thread
	///
	/// spawn() starts a new thread. The new thread starts execution
	/// by invoking `func(usize)`; `arg` is passed as the argument
	/// to `func`. `prio` defines the priority of the new thread,
	/// which can be between `LOW_PRIO` and `HIGH_PRIO`.
	/// `core_id` defines the core, where the thread is located.
	/// A negative value give the operating system the possibility
	/// to select the core by its own.
	#[link_name = "sys_spawn"]
	pub fn spawn(
	id: *mut Tid,
	func: extern "C" fn(usize),
	arg: usize,
	prio: u8,
	core_id: isize,
	) -> i32;

	/// spawn a new thread with user-specified stack size
	///
	/// spawn2() starts a new thread. The new thread starts execution
	/// by invoking `func(usize)`; `arg` is passed as the argument
	/// to `func`. `prio` defines the priority of the new thread,
	/// which can be between `LOW_PRIO` and `HIGH_PRIO`.
	/// `core_id` defines the core, where the thread is located.
	/// A negative value give the operating system the possibility
	/// to select the core by its own.
	/// In contrast to spawn(), spawn2() is able to define the
	/// stack size.
	#[link_name = "sys_spawn2"]
	pub fn spawn2(
	func: extern "C" fn(usize),
	arg: usize,
	prio: u8,
	stack_size: usize,
	core_id: isize,
	) -> Tid;

	/// join with a terminated thread
	///
	/// The join() function waits for the thread specified by `id`
	/// to terminate.
	#[link_name = "sys_join"]
	pub fn join(id: Tid) -> i32;

	/// yield the processor
	///
	/// causes the calling thread to relinquish the CPU. The thread
	/// is moved to the end of the queue for its static priority.
	#[link_name = "sys_yield"]
	pub fn yield_now();

	/// get current time
	///
	/// The clock_gettime() functions allow the calling thread
	/// to retrieve the value used by a clock which is specified
	/// by `clock_id`.
	///
	/// `CLOCK_REALTIME`: the system's real time clock,
	/// expressed as the amount of time since the Epoch.
	///
	/// `CLOCK_MONOTONIC`: clock that increments monotonically,
	/// tracking the time since an arbitrary point
	#[link_name = "sys_clock_gettime"]
	pub fn clock_gettime(clock_id: u64, tp: *mut timespec) -> i32;

	/// open and possibly create a file
	///
	/// The open() system call opens the file specified by `name`.
	/// If the specified file does not exist, it may optionally
	/// be created by open().
	#[link_name = "sys_open"]
	pub fn open(name: *const i8, flags: i32, mode: i32) -> i32;

	/// delete the file it refers to `name`
	#[link_name = "sys_unlink"]
	pub fn unlink(name: *const i8) -> i32;

	/// determines the number of activated processors
	#[link_name = "sys_processor_count"]
	pub fn get_processor_count() -> usize;

	#[link_name = "sys_malloc"]
	pub fn malloc(size: usize, align: usize) -> *mut u8;

	#[doc(hidden)]
	#[link_name = "sys_realloc"]
	pub fn realloc(ptr: mut u8, size: usize, align: usize, new_size: usize) -> mut u8;

	#[doc(hidden)]
	#[link_name = "sys_free"]
	pub fn free(ptr: *mut u8, size: usize, align: usize);

	#[link_name = "sys_notify"]
	pub fn notify(id: usize, count: i32) -> i32;

	#[doc(hidden)]
	#[link_name = "sys_add_queue"]
	pub fn add_queue(id: usize, timeout_ns: i64) -> i32;

	#[doc(hidden)]
	#[link_name = "sys_wait"]
	pub fn wait(id: usize) -> i32;

	#[doc(hidden)]
	#[link_name = "sys_init_queue"]
	pub fn init_queue(id: usize) -> i32;

	#[doc(hidden)]
	#[link_name = "sys_destroy_queue"]
	pub fn destroy_queue(id: usize) -> i32;

	/// initialize the network stack
	#[link_name = "sys_network_init"]
	pub fn network_init() -> i32;

	/// Add current task to the queue of blocked tasks. After calling `block_current_task`,
	/// call `yield_now` to switch to another task.
	#[link_name = "sys_block_current_task"]
	pub fn block_current_task();

	/// Add current task to the queue of blocked tasks, but wake it when `timeout` milliseconds
	/// have elapsed.
	///
	/// After calling `block_current_task`, call `yield_now` to switch to another task.
	#[link_name = "sys_block_current_task_with_timeout"]
	pub fn block_current_task_with_timeout(timeout: u64);

	/// Wakeup task with the thread id `tid`
	#[link_name = "sys_wakeup_taskt"]
	pub fn wakeup_task(tid: Tid);

	#[link_name = "sys_accept"]
	pub fn accept(s: i32, addr: mut sockaddr, addrlen: mut socklen_t) -> i32;

	/// bind a name to a socket
	#[link_name = "sys_bind"]
	pub fn bind(s: i32, name: *const sockaddr, namelen: socklen_t) -> i32;

	#[link_name = "sys_connect"]
	pub fn connect(s: i32, name: *const sockaddr, namelen: socklen_t) -> i32;

	/// read from a file descriptor
	///
	/// read() attempts to read `len` bytes of data from the object
	/// referenced by the descriptor `fd` into the buffer pointed
	/// to by `buf`.
	#[link_name = "sys_read"]
	pub fn read(fd: i32, buf: *mut u8, len: usize) -> isize;

	/// Fill `len` bytes in `buf` with cryptographically secure random data.
	///
	/// Returns either the number of bytes written to buf (a positive value) or
	/// * `-EINVAL` if `flags` contains unknown flags.
	/// * `-ENOSYS` if the system does not support random data generation.
	#[link_name = "sys_read_entropy"]
	pub fn read_entropy(buf: *mut u8, len: usize, flags: u32) -> isize;

	/// receive() a message from a socket
	#[link_name = "sys_recv"]
	pub fn recv(socket: i32, buf: *mut u8, len: usize, flags: i32) -> isize;

	/// receive() a message from a socket
	#[link_name = "sys_recvfrom"]
	pub fn recvfrom(
	socket: i32,
	buf: *mut u8,
	len: usize,
	flags: i32,
	addr: *mut sockaddr,
	addrlen: *mut socklen_t,
	) -> isize;

	/// write to a file descriptor
	///
	/// write() attempts to write `len` of data to the object
	/// referenced by the descriptor `fd` from the
	/// buffer pointed to by `buf`.
	#[link_name = "sys_write"]
	pub fn write(fd: i32, buf: *const u8, len: usize) -> isize;

	/// close a file descriptor
	///
	/// The close() call deletes a file descriptor `fd` from the object
	/// reference table.
	#[link_name = "sys_close"]
	pub fn close(fd: i32) -> i32;

	/// duplicate an existing file descriptor
	#[link_name = "sys_dup"]
	pub fn dup(fd: i32) -> i32;

	#[link_name = "sys_getpeername"]
	pub fn getpeername(s: i32, name: mut sockaddr, namelen: mut socklen_t) -> i32;

	#[link_name = "sys_getsockname"]
	pub fn getsockname(s: i32, name: mut sockaddr, namelen: mut socklen_t) -> i32;

	#[link_name = "sys_getsockopt"]
	pub fn getsockopt(
	s: i32,
	level: i32,
	optname: i32,
	optval: *mut c_void,
	optlen: *mut socklen_t,
	) -> i32;

	#[link_name = "sys_setsockopt"]
	pub fn setsockopt(
	s: i32,
	level: i32,
	optname: i32,
	optval: *const c_void,
	optlen: socklen_t,
	) -> i32;

	#[link_name = "sys_ioctl"]
	pub fn ioctl(s: i32, cmd: i32, argp: *mut c_void) -> i32;

	#[link_name = "sys_pool"]
	pub fn poll(fds: *mut pollfd, nfds: nfds_t, timeout: i32) -> i32;

	/// listen for connections on a socket
	///
	/// The `backlog` parameter defines the maximum length for the queue of pending
	/// connections. Currently, the `backlog` must be one.
	#[link_name = "sys_listen"]
	pub fn listen(s: i32, backlog: i32) -> i32;

	#[link_name = "sys_send"]
	pub fn send(s: i32, mem: *const c_void, len: usize, flags: i32) -> isize;

	#[link_name = "sys_sendto"]
	pub fn sendto(
	s: i32,
	mem: *const c_void,
	len: usize,
	flags: i32,
	to: *const sockaddr,
	tolen: socklen_t,
	) -> isize;

	/// shut down part of a full-duplex connection
	#[link_name = "sys_shutdown_socket"]
	pub fn shutdown_socket(s: i32, how: i32) -> i32;

	#[link_name = "sys_socket"]
	pub fn socket(domain: i32, type_: i32, protocol: i32) -> i32;

	#[link_name = "sys_freeaddrinfo"]
	pub fn freeaddrinfo(ai: *mut addrinfo);

	#[link_name = "sys_getaddrinfo"]
	pub fn getaddrinfo(
	nodename: *const i8,
	servname: *const u8,
	hints: *const addrinfo,
	res: mut mut addrinfo,
	) -> i32;

	fn sys_get_priority() -> u8;
	fn sys_set_priority(tid: Tid, prio: u8);
	}

	/// Determine the priority of the current thread
	#[inline(always)]
	pub unsafe fn get_priority() -> Priority {
	Priority::from(sys_get_priority())
	}

	/// Determine the priority of the current thread
	#[inline(always)]
	pub unsafe fn set_priority(tid: Tid, prio: Priority) {
	sys_set_priority(tid, prio.into());
	}