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#![allow(non_upper_case_globals)]
#![allow(non_camel_case_types)]
#![allow(non_snake_case)]
use crate::vmcontext::VMContext;
use crate::RwLock;
use core::borrow::{Borrow, BorrowMut};
use core::cell::Cell;
use lazy_static::lazy_static;
#[derive(Default)]
struct TrapContext {
tried_to_install_signal_handlers: Cell<bool>,
have_signal_handlers: Cell<bool>,
}
extern "C" {
fn EnsureEagerSignalHandlers() -> libc::c_int;
#[cfg(any(target_os = "macos", target_os = "ios"))]
fn EnsureDarwinMachPorts() -> libc::c_int;
}
struct InstallState {
tried: bool,
success: bool,
}
impl InstallState {
fn new() -> Self {
Self {
tried: false,
success: false,
}
}
}
lazy_static! {
static ref EAGER_INSTALL_STATE: RwLock<InstallState> = RwLock::new(InstallState::new());
static ref LAZY_INSTALL_STATE: RwLock<InstallState> = RwLock::new(InstallState::new());
}
#[no_mangle]
pub extern "C" fn wasmtime_init_eager() {
let mut locked = EAGER_INSTALL_STATE.write().unwrap();
let state = locked.borrow_mut();
if state.tried {
return;
}
state.tried = true;
assert!(!state.success);
if unsafe { EnsureEagerSignalHandlers() == 0 } {
return;
}
state.success = true;
}
thread_local! {
static TRAP_CONTEXT: TrapContext = TrapContext::default();
}
#[no_mangle]
pub extern "C" fn wasmtime_init_finish(vmctx: &mut VMContext) {
if !TRAP_CONTEXT.with(|cx| cx.tried_to_install_signal_handlers.get()) {
TRAP_CONTEXT.with(|cx| {
cx.tried_to_install_signal_handlers.set(true);
assert!(!cx.have_signal_handlers.get());
});
{
let locked = EAGER_INSTALL_STATE.read().unwrap();
let state = locked.borrow();
assert!(
state.tried,
"call wasmtime_init_eager before calling wasmtime_init_finish"
);
if !state.success {
return;
}
}
#[cfg(any(target_os = "macos", target_os = "ios"))]
ensure_darwin_mach_ports();
TRAP_CONTEXT.with(|cx| {
cx.have_signal_handlers.set(true);
})
}
let instance = unsafe { vmctx.instance() };
let have_signal_handlers = TRAP_CONTEXT.with(|cx| cx.have_signal_handlers.get());
if !have_signal_handlers && instance.needs_signal_handlers() {
panic!("failed to install signal handlers");
}
}
#[cfg(any(target_os = "macos", target_os = "ios"))]
fn ensure_darwin_mach_ports() {
let mut locked = LAZY_INSTALL_STATE.write().unwrap();
let state = locked.borrow_mut();
if state.tried {
return;
}
state.tried = true;
assert!(!state.success);
if unsafe { EnsureDarwinMachPorts() != 0 } {
return;
}
state.success = true;
}