zircon/kernel/object/io_buffer_dispatcher_ffi.rs

// Copyright 2026 The Fuchsia Authors
//
// Use of this source code is governed by a MIT-style
// license that can be found in the LICENSE file or at
// https://opensource.org/licenses/MIT

use crate::object::handle::KernelHandle;
use crate::object::io_buffer_dispatcher::{IoBufferDispatcher, IoBufferDispatcherState};
use crate::vm::vm_object::{VmObject, VmObjectChildObserver};
use core::ffi::c_char;
use core::mem::MaybeUninit;
use fbl::RefPtr;
use zx_status::Status;
use zx_types::{ZX_MAX_NAME_LEN, zx_info_iob_t, zx_iob_region_info_t, zx_rights_t, zx_status_t};

unsafe extern "C" {
    pub(super) fn cpp_io_buffer_dispatcher_create(
        holder: *mut (),
        endpoint_id: usize,
        shared_state: *mut (),
        handle_out: *mut MaybeUninit<KernelHandle<IoBufferDispatcher>>,
    ) -> zx_status_t;

    pub(super) fn cpp_io_buffer_dispatcher_as_child_observer(
        disp: &IoBufferDispatcher,
    ) -> *mut VmObjectChildObserver;
}

crate::object::dispatcher::impl_peered_dispatcher_state_init!(
    IoBufferDispatcher,
    IoBufferDispatcherState,
    endpoint_id: usize,
    shared_state: *mut (),
);

#[unsafe(no_mangle)]
pub unsafe extern "C" fn rust_io_buffer_dispatcher_on_zero_child(disp: &IoBufferDispatcher) {
    disp.on_zero_child();
}

#[unsafe(no_mangle)]
pub unsafe extern "C" fn rust_io_buffer_dispatcher_get_name(
    disp: &IoBufferDispatcher,
    out_name: *mut [u8; ZX_MAX_NAME_LEN],
) -> zx_status_t {
    let out = unsafe { &mut *out_name };
    Status::result_into_raw(disp.get_name(out))
}

#[unsafe(no_mangle)]
pub unsafe extern "C" fn rust_io_buffer_dispatcher_set_name(
    disp: &IoBufferDispatcher,
    name: *const c_char,
    len: usize,
) -> zx_status_t {
    let name_bytes =
        if len == 0 { &[] } else { unsafe { core::slice::from_raw_parts(name.cast(), len) } };
    Status::result_into_raw(disp.set_name(name_bytes))
}

#[unsafe(no_mangle)]
pub unsafe extern "C" fn rust_io_buffer_dispatcher_region_count(
    disp: &IoBufferDispatcher,
) -> usize {
    disp.region_count()
}

#[unsafe(no_mangle)]
pub unsafe extern "C" fn rust_io_buffer_dispatcher_get_map_rights(
    disp: &IoBufferDispatcher,
    iob_rights: zx_rights_t,
    region_index: usize,
) -> zx_rights_t {
    disp.get_map_rights(iob_rights, region_index)
}

#[unsafe(no_mangle)]
pub unsafe extern "C" fn rust_io_buffer_dispatcher_get_vmo(
    disp: &IoBufferDispatcher,
    region_index: usize,
) -> *mut VmObject {
    match disp.get_vmo(region_index) {
        Ok(vmo) => RefPtr::into_raw(vmo).cast_mut(),
        Err(_) => core::ptr::null_mut(),
    }
}

#[unsafe(no_mangle)]
pub unsafe extern "C" fn rust_io_buffer_dispatcher_get_info(
    disp: &IoBufferDispatcher,
) -> zx_info_iob_t {
    disp.get_info()
}

#[unsafe(no_mangle)]
pub unsafe extern "C" fn rust_io_buffer_dispatcher_get_region_info(
    disp: &IoBufferDispatcher,
    index: usize,
) -> zx_iob_region_info_t {
    disp.get_region_info(index)
}