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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-17 12:02:58 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-17 12:02:58 +0000
commit698f8c2f01ea549d77d7dc3338a12e04c11057b9 (patch)
tree173a775858bd501c378080a10dca74132f05bc50 /vendor/hermit-abi-0.1.19/src
parentInitial commit. (diff)
downloadrustc-698f8c2f01ea549d77d7dc3338a12e04c11057b9.tar.xz
rustc-698f8c2f01ea549d77d7dc3338a12e04c11057b9.zip
Adding upstream version 1.64.0+dfsg1.upstream/1.64.0+dfsg1
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'vendor/hermit-abi-0.1.19/src')
-rw-r--r--vendor/hermit-abi-0.1.19/src/lib.rs490
-rw-r--r--vendor/hermit-abi-0.1.19/src/tcplistener.rs13
-rw-r--r--vendor/hermit-abi-0.1.19/src/tcpstream.rs109
3 files changed, 612 insertions, 0 deletions
diff --git a/vendor/hermit-abi-0.1.19/src/lib.rs b/vendor/hermit-abi-0.1.19/src/lib.rs
new file mode 100644
index 000000000..9151faf56
--- /dev/null
+++ b/vendor/hermit-abi-0.1.19/src/lib.rs
@@ -0,0 +1,490 @@
+//! `hermit-abi` is small interface to call functions from the unikernel
+//! [RustyHermit](https://github.com/hermitcore/libhermit-rs).
+
+#![no_std]
+#![allow(clippy::missing_safety_doc)]
+#![allow(clippy::result_unit_err)]
+
+extern crate libc;
+
+pub mod tcplistener;
+pub mod tcpstream;
+
+use libc::c_void;
+
+// sysmbols, which are part of the library operating system
+
+extern "Rust" {
+ fn sys_secure_rand64() -> Option<u64>;
+ fn sys_secure_rand32() -> Option<u32>;
+}
+
+extern "C" {
+ fn sys_rand() -> u32;
+ fn sys_srand(seed: u32);
+ fn sys_get_processor_count() -> usize;
+ fn sys_malloc(size: usize, align: usize) -> *mut u8;
+ fn sys_realloc(ptr: *mut u8, size: usize, align: usize, new_size: usize) -> *mut u8;
+ fn sys_free(ptr: *mut u8, size: usize, align: usize);
+ fn sys_init_queue(ptr: usize) -> i32;
+ fn sys_notify(id: usize, count: i32) -> i32;
+ fn sys_add_queue(id: usize, timeout_ns: i64) -> i32;
+ fn sys_wait(id: usize) -> i32;
+ fn sys_destroy_queue(id: usize) -> i32;
+ fn sys_read(fd: i32, buf: *mut u8, len: usize) -> isize;
+ fn sys_write(fd: i32, buf: *const u8, len: usize) -> isize;
+ fn sys_close(fd: i32) -> i32;
+ fn sys_sem_init(sem: *mut *const c_void, value: u32) -> i32;
+ fn sys_sem_destroy(sem: *const c_void) -> i32;
+ fn sys_sem_post(sem: *const c_void) -> i32;
+ fn sys_sem_trywait(sem: *const c_void) -> i32;
+ fn sys_sem_timedwait(sem: *const c_void, ms: u32) -> i32;
+ fn sys_recmutex_init(recmutex: *mut *const c_void) -> i32;
+ fn sys_recmutex_destroy(recmutex: *const c_void) -> i32;
+ fn sys_recmutex_lock(recmutex: *const c_void) -> i32;
+ fn sys_recmutex_unlock(recmutex: *const c_void) -> i32;
+ fn sys_getpid() -> u32;
+ fn sys_exit(arg: i32) -> !;
+ fn sys_abort() -> !;
+ fn sys_usleep(usecs: u64);
+ fn sys_spawn(
+ id: *mut Tid,
+ func: extern "C" fn(usize),
+ arg: usize,
+ prio: u8,
+ core_id: isize,
+ ) -> i32;
+ fn sys_spawn2(
+ func: extern "C" fn(usize),
+ arg: usize,
+ prio: u8,
+ stack_size: usize,
+ core_id: isize,
+ ) -> Tid;
+ fn sys_join(id: Tid) -> i32;
+ fn sys_yield();
+ fn sys_clock_gettime(clock_id: u64, tp: *mut timespec) -> i32;
+ fn sys_open(name: *const i8, flags: i32, mode: i32) -> i32;
+ fn sys_unlink(name: *const i8) -> i32;
+ fn sys_network_init() -> i32;
+ fn sys_block_current_task();
+ fn sys_wakeup_task(tid: Tid);
+ fn sys_get_priority() -> u8;
+}
+
+/// 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 CLOCK_REALTIME: u64 = 1;
+pub const CLOCK_MONOTONIC: u64 = 4;
+pub const STDIN_FILENO: libc::c_int = 0;
+pub const STDOUT_FILENO: libc::c_int = 1;
+pub const STDERR_FILENO: libc::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: libc::c_int) -> bool {
+ false
+}
+
+/// intialize the network stack
+pub fn network_init() -> i32 {
+ unsafe { sys_network_init() }
+}
+
+/// `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),
+}
+
+/// determines the number of activated processors
+#[inline(always)]
+pub unsafe fn get_processor_count() -> usize {
+ sys_get_processor_count()
+}
+
+#[doc(hidden)]
+#[inline(always)]
+pub unsafe fn malloc(size: usize, align: usize) -> *mut u8 {
+ sys_malloc(size, align)
+}
+
+#[doc(hidden)]
+#[inline(always)]
+pub unsafe fn realloc(ptr: *mut u8, size: usize, align: usize, new_size: usize) -> *mut u8 {
+ sys_realloc(ptr, size, align, new_size)
+}
+
+#[doc(hidden)]
+#[inline(always)]
+pub unsafe fn free(ptr: *mut u8, size: usize, align: usize) {
+ sys_free(ptr, size, align)
+}
+
+#[inline(always)]
+pub unsafe fn notify(id: usize, count: i32) -> i32 {
+ sys_notify(id, count)
+}
+
+#[doc(hidden)]
+#[inline(always)]
+pub unsafe fn add_queue(id: usize, timeout_ns: i64) -> i32 {
+ sys_add_queue(id, timeout_ns)
+}
+
+#[doc(hidden)]
+#[inline(always)]
+pub unsafe fn wait(id: usize) -> i32 {
+ sys_wait(id)
+}
+
+#[doc(hidden)]
+#[inline(always)]
+pub unsafe fn init_queue(id: usize) -> i32 {
+ sys_init_queue(id)
+}
+
+#[doc(hidden)]
+#[inline(always)]
+pub unsafe fn destroy_queue(id: usize) -> i32 {
+ sys_destroy_queue(id)
+}
+
+/// 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`.
+#[inline(always)]
+pub unsafe fn read(fd: i32, buf: *mut u8, len: usize) -> isize {
+ sys_read(fd, buf, len)
+}
+
+/// 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`.
+#[inline(always)]
+pub unsafe fn write(fd: i32, buf: *const u8, len: usize) -> isize {
+ sys_write(fd, buf, len)
+}
+
+/// close a file descriptor
+///
+/// The close() call deletes a file descriptor `fd` from the object
+/// reference table.
+#[inline(always)]
+pub unsafe fn close(fd: i32) -> i32 {
+ sys_close(fd)
+}
+
+/// sem_init() initializes the unnamed semaphore at the address
+/// pointed to by `sem`. The `value` argument specifies the
+/// initial value for the semaphore.
+#[inline(always)]
+pub unsafe fn sem_init(sem: *mut *const c_void, value: u32) -> i32 {
+ sys_sem_init(sem, value)
+}
+
+/// sem_destroy() frees the unnamed semaphore at the address
+/// pointed to by `sem`.
+#[inline(always)]
+pub unsafe fn sem_destroy(sem: *const c_void) -> i32 {
+ sys_sem_destroy(sem)
+}
+
+/// 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.
+#[inline(always)]
+pub unsafe fn sem_post(sem: *const c_void) -> i32 {
+ sys_sem_post(sem)
+}
+
+/// 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.
+#[inline(always)]
+pub unsafe fn sem_trywait(sem: *const c_void) -> i32 {
+ sys_sem_trywait(sem)
+}
+
+/// 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.
+#[inline(always)]
+pub unsafe fn sem_timedwait(sem: *const c_void, ms: u32) -> i32 {
+ sys_sem_timedwait(sem, ms)
+}
+
+#[doc(hidden)]
+#[inline(always)]
+pub unsafe fn recmutex_init(recmutex: *mut *const c_void) -> i32 {
+ sys_recmutex_init(recmutex)
+}
+
+#[doc(hidden)]
+#[inline(always)]
+pub unsafe fn recmutex_destroy(recmutex: *const c_void) -> i32 {
+ sys_recmutex_destroy(recmutex)
+}
+
+#[doc(hidden)]
+#[inline(always)]
+pub unsafe fn recmutex_lock(recmutex: *const c_void) -> i32 {
+ sys_recmutex_lock(recmutex)
+}
+
+#[doc(hidden)]
+#[inline(always)]
+pub unsafe fn recmutex_unlock(recmutex: *const c_void) -> i32 {
+ sys_recmutex_unlock(recmutex)
+}
+
+/// Determines the id of the current thread
+#[inline(always)]
+pub unsafe fn getpid() -> u32 {
+ sys_getpid()
+}
+
+/// cause normal termination and return `arg`
+/// to the host system
+#[inline(always)]
+pub unsafe fn exit(arg: i32) -> ! {
+ sys_exit(arg)
+}
+
+/// cause abnormal termination
+#[inline(always)]
+pub unsafe fn abort() -> ! {
+ sys_abort()
+}
+
+/// suspend execution for microsecond intervals
+///
+/// The usleep() function suspends execution of the calling
+/// thread for (at least) `usecs` microseconds.
+#[inline(always)]
+pub unsafe fn usleep(usecs: u64) {
+ sys_usleep(usecs)
+}
+
+/// 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.
+#[inline(always)]
+pub unsafe fn spawn(
+ id: *mut Tid,
+ func: extern "C" fn(usize),
+ arg: usize,
+ prio: u8,
+ core_id: isize,
+) -> i32 {
+ sys_spawn(id, func, arg, prio, core_id)
+}
+
+/// 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.
+#[inline(always)]
+pub unsafe fn spawn2(
+ func: extern "C" fn(usize),
+ arg: usize,
+ prio: u8,
+ stack_size: usize,
+ core_id: isize,
+) -> Tid {
+ sys_spawn2(func, arg, prio, stack_size, core_id)
+}
+
+/// join with a terminated thread
+///
+/// The join() function waits for the thread specified by `id`
+/// to terminate.
+#[inline(always)]
+pub unsafe fn join(id: Tid) -> i32 {
+ sys_join(id)
+}
+
+/// 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.
+#[inline(always)]
+pub unsafe fn yield_now() {
+ sys_yield()
+}
+
+/// 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
+#[inline(always)]
+pub unsafe fn clock_gettime(clock_id: u64, tp: *mut timespec) -> i32 {
+ sys_clock_gettime(clock_id, tp)
+}
+
+/// 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().
+#[inline(always)]
+pub unsafe fn open(name: *const i8, flags: i32, mode: i32) -> i32 {
+ sys_open(name, flags, mode)
+}
+
+/// delete the file it refers to `name`
+#[inline(always)]
+pub unsafe fn unlink(name: *const i8) -> i32 {
+ sys_unlink(name)
+}
+
+/// The largest number `rand` will return
+pub const RAND_MAX: u64 = 2_147_483_647;
+
+/// The function computes a sequence of pseudo-random integers
+/// in the range of 0 to RAND_MAX
+#[inline(always)]
+pub unsafe fn rand() -> u32 {
+ sys_rand()
+}
+
+/// The function sets its argument as the seed for a new sequence
+/// of pseudo-random numbers to be returned by `rand`
+#[inline(always)]
+pub unsafe fn srand(seed: u32) {
+ sys_srand(seed);
+}
+
+/// Create a cryptographicly secure 32bit random number with the support of
+/// the underlying hardware. If the required hardware isn't available,
+/// the function returns `None`.
+#[inline(always)]
+pub unsafe fn secure_rand32() -> Option<u32> {
+ sys_secure_rand32()
+}
+
+/// Create a cryptographicly secure 64bit random number with the support of
+/// the underlying hardware. If the required hardware isn't available,
+/// the function returns `None`.
+#[inline(always)]
+pub unsafe fn secure_rand64() -> Option<u64> {
+ sys_secure_rand64()
+}
+
+/// Add current task to the queue of blocked tasl. After calling `block_current_task`,
+/// call `yield_now` to switch to another task.
+#[inline(always)]
+pub unsafe fn block_current_task() {
+ sys_block_current_task();
+}
+
+/// Wakeup task with the thread id `tid`
+#[inline(always)]
+pub unsafe fn wakeup_task(tid: Tid) {
+ sys_wakeup_task(tid);
+}
+
+/// Determine the priority of the current thread
+#[inline(always)]
+pub unsafe fn get_priority() -> Priority {
+ Priority::from(sys_get_priority())
+}
diff --git a/vendor/hermit-abi-0.1.19/src/tcplistener.rs b/vendor/hermit-abi-0.1.19/src/tcplistener.rs
new file mode 100644
index 000000000..5afe67364
--- /dev/null
+++ b/vendor/hermit-abi-0.1.19/src/tcplistener.rs
@@ -0,0 +1,13 @@
+//! `tcplistener` provide an interface to establish tcp socket server.
+
+use crate::{Handle, IpAddress};
+
+extern "Rust" {
+ fn sys_tcp_listener_accept(port: u16) -> Result<(Handle, IpAddress, u16), ()>;
+}
+
+/// Wait for connection at specified address.
+#[inline(always)]
+pub fn accept(port: u16) -> Result<(Handle, IpAddress, u16), ()> {
+ unsafe { sys_tcp_listener_accept(port) }
+}
diff --git a/vendor/hermit-abi-0.1.19/src/tcpstream.rs b/vendor/hermit-abi-0.1.19/src/tcpstream.rs
new file mode 100644
index 000000000..3024d379f
--- /dev/null
+++ b/vendor/hermit-abi-0.1.19/src/tcpstream.rs
@@ -0,0 +1,109 @@
+//! `tcpstream` provide an interface to establish tcp socket client.
+
+use crate::{Handle, IpAddress};
+
+extern "Rust" {
+ fn sys_tcp_stream_connect(ip: &[u8], port: u16, timeout: Option<u64>) -> Result<Handle, ()>;
+ fn sys_tcp_stream_close(handle: Handle) -> Result<(), ()>;
+ fn sys_tcp_stream_read(handle: Handle, buffer: &mut [u8]) -> Result<usize, ()>;
+ fn sys_tcp_stream_write(handle: Handle, buffer: &[u8]) -> Result<usize, ()>;
+ fn sys_tcp_stream_set_read_timeout(handle: Handle, timeout: Option<u64>) -> Result<(), ()>;
+ fn sys_tcp_stream_get_read_timeout(handle: Handle) -> Result<Option<u64>, ()>;
+ fn sys_tcp_stream_set_write_timeout(handle: Handle, timeout: Option<u64>) -> Result<(), ()>;
+ fn sys_tcp_stream_get_write_timeout(handle: Handle) -> Result<Option<u64>, ()>;
+ fn sys_tcp_stream_peek(handle: Handle, buf: &mut [u8]) -> Result<usize, ()>;
+ fn sys_tcp_stream_set_nonblocking(handle: Handle, mode: bool) -> Result<(), ()>;
+ fn sys_tcp_stream_set_tll(handle: Handle, ttl: u32) -> Result<(), ()>;
+ fn sys_tcp_stream_get_tll(handle: Handle) -> Result<u32, ()>;
+ fn sys_tcp_stream_shutdown(handle: Handle, how: i32) -> Result<(), ()>;
+ fn sys_tcp_stream_peer_addr(handle: Handle) -> Result<(IpAddress, u16), ()>;
+}
+
+/// Opens a TCP connection to a remote host.
+#[inline(always)]
+pub fn connect(ip: &[u8], port: u16, timeout: Option<u64>) -> Result<Handle, ()> {
+ unsafe { sys_tcp_stream_connect(ip, port, timeout) }
+}
+
+/// Close a TCP connection
+#[inline(always)]
+pub fn close(handle: Handle) -> Result<(), ()> {
+ unsafe { sys_tcp_stream_close(handle) }
+}
+
+#[inline(always)]
+pub fn peek(handle: Handle, buf: &mut [u8]) -> Result<usize, ()> {
+ unsafe { sys_tcp_stream_peek(handle, buf) }
+}
+
+#[inline(always)]
+pub fn peer_addr(handle: Handle) -> Result<(IpAddress, u16), ()> {
+ unsafe { sys_tcp_stream_peer_addr(handle) }
+}
+#[inline(always)]
+pub fn read(handle: Handle, buffer: &mut [u8]) -> Result<usize, ()> {
+ unsafe { sys_tcp_stream_read(handle, buffer) }
+}
+
+#[inline(always)]
+pub fn write(handle: Handle, buffer: &[u8]) -> Result<usize, ()> {
+ unsafe { sys_tcp_stream_write(handle, buffer) }
+}
+
+#[inline(always)]
+pub fn set_read_timeout(handle: Handle, timeout: Option<u64>) -> Result<(), ()> {
+ unsafe { sys_tcp_stream_set_read_timeout(handle, timeout) }
+}
+
+#[inline(always)]
+pub fn set_write_timeout(handle: Handle, timeout: Option<u64>) -> Result<(), ()> {
+ unsafe { sys_tcp_stream_set_write_timeout(handle, timeout) }
+}
+
+#[inline(always)]
+pub fn get_read_timeout(handle: Handle) -> Result<Option<u64>, ()> {
+ unsafe { sys_tcp_stream_get_read_timeout(handle) }
+}
+
+#[inline(always)]
+pub fn get_write_timeout(handle: Handle) -> Result<Option<u64>, ()> {
+ unsafe { sys_tcp_stream_get_write_timeout(handle) }
+}
+
+#[inline(always)]
+pub fn set_nodelay(_: Handle, mode: bool) -> Result<(), ()> {
+ // smoltcp does not support Nagle's algorithm
+ // => to enable Nagle's algorithm isn't possible
+ if mode {
+ Ok(())
+ } else {
+ Err(())
+ }
+}
+
+#[inline(always)]
+pub fn nodelay(_: Handle) -> Result<bool, ()> {
+ // smoltcp does not support Nagle's algorithm
+ // => return always true
+ Ok(true)
+}
+
+#[inline(always)]
+pub fn set_nonblocking(handle: Handle, mode: bool) -> Result<(), ()> {
+ unsafe { sys_tcp_stream_set_nonblocking(handle, mode) }
+}
+
+#[inline(always)]
+pub fn set_tll(handle: Handle, ttl: u32) -> Result<(), ()> {
+ unsafe { sys_tcp_stream_set_tll(handle, ttl) }
+}
+
+#[inline(always)]
+pub fn get_tll(handle: Handle) -> Result<u32, ()> {
+ unsafe { sys_tcp_stream_get_tll(handle) }
+}
+
+#[inline(always)]
+pub fn shutdown(handle: Handle, how: i32) -> Result<(), ()> {
+ unsafe { sys_tcp_stream_shutdown(handle, how) }
+}