unpark

fn unpark(tids: []const UnparkTid, addr_hint: ?*const anyopaque) void

File

Code

fn unpark(tids: []const UnparkTid, addr_hint: ?*const anyopaque) void {
    comptime assert(use_parking_futex or use_parking_sleep);
    switch (native_os) {
        .windows => {
            // TODO: this condition is currently disabled because mingw-w64 does not contain this
            // symbol. Once it's added, enable this check to use the new bulk API where possible.
            if (false and (builtin.os.version_range.windows.isAtLeast(.win11_dt) orelse false)) {
                _ = windows.ntdll.NtAlertMultipleThreadByThreadId(tids.ptr, @intCast(tids.len), null, null);
            } else {
                for (tids) |tid| {
                    _ = windows.ntdll.NtAlertThreadByThreadId(@intCast(tid));
                }
            }
        },
        .netbsd => {
            switch (posix.errno(std.c._lwp_unpark_all(@ptrCast(tids.ptr), tids.len, addr_hint))) {
                .SUCCESS => return,
                // For errors, fall through to a loop over `tids`, though this is only expected to
                // be possible for ENOMEM (even that is questionable) and ESRCH (see comment below).
                .SRCH => {},
                .FAULT => recoverableOsBugDetected(),
                .INVAL => recoverableOsBugDetected(),
                .NOMEM => {},
                else => recoverableOsBugDetected(),
            }
            for (tids) |tid| {
                switch (posix.errno(std.c._lwp_unpark(@bitCast(tid), addr_hint))) {
                    .SUCCESS => {},
                    .SRCH => {
                        // This can happen in a rare race: the thread might have been spuriously
                        // unparked, so already observed the changing status, and from there have
                        // exited. That's okay, because the thread has woken up like we wanted.
                    },
                    else => recoverableOsBugDetected(),
                }
            }
        },
        .illumos => @panic("TODO: illumos lwp_unpark"),
        else => comptime unreachable,
    }
}