xref: /openbmc/qemu/rust/qemu-api/src/definitions.rs (revision 646b5378)
1 // Copyright 2024, Linaro Limited
2 // Author(s): Manos Pitsidianakis <manos.pitsidianakis@linaro.org>
3 // SPDX-License-Identifier: GPL-2.0-or-later
4 
5 //! Definitions required by QEMU when registering a device.
6 
7 use ::core::ffi::{c_void, CStr};
8 
9 use crate::bindings::{Object, ObjectClass, TypeInfo};
10 
11 /// Trait a type must implement to be registered with QEMU.
12 pub trait ObjectImpl {
13     type Class;
14     const TYPE_INFO: TypeInfo;
15     const TYPE_NAME: &'static CStr;
16     const PARENT_TYPE_NAME: Option<&'static CStr>;
17     const ABSTRACT: bool;
18     const INSTANCE_INIT: Option<unsafe extern "C" fn(obj: *mut Object)>;
19     const INSTANCE_POST_INIT: Option<unsafe extern "C" fn(obj: *mut Object)>;
20     const INSTANCE_FINALIZE: Option<unsafe extern "C" fn(obj: *mut Object)>;
21 }
22 
23 pub trait Class {
24     const CLASS_INIT: Option<unsafe extern "C" fn(klass: *mut ObjectClass, data: *mut c_void)>;
25     const CLASS_BASE_INIT: Option<
26         unsafe extern "C" fn(klass: *mut ObjectClass, data: *mut c_void),
27     >;
28 }
29 
30 #[macro_export]
31 macro_rules! module_init {
32     ($type:ident => $body:block) => {
33         const _: () = {
34             #[used]
35             #[cfg_attr(
36                 not(any(target_vendor = "apple", target_os = "windows")),
37                 link_section = ".init_array"
38             )]
39             #[cfg_attr(target_vendor = "apple", link_section = "__DATA,__mod_init_func")]
40             #[cfg_attr(target_os = "windows", link_section = ".CRT$XCU")]
41             pub static LOAD_MODULE: extern "C" fn() = {
42                 extern "C" fn init_fn() {
43                     $body
44                 }
45 
46                 extern "C" fn ctor_fn() {
47                     unsafe {
48                         $crate::bindings::register_module_init(
49                             Some(init_fn),
50                             $crate::bindings::module_init_type::$type,
51                         );
52                     }
53                 }
54 
55                 ctor_fn
56             };
57         };
58     };
59 
60     // shortcut because it's quite common that $body needs unsafe {}
61     ($type:ident => unsafe $body:block) => {
62         $crate::module_init! {
63             $type => { unsafe { $body } }
64         }
65     };
66 }
67 
68 #[macro_export]
69 macro_rules! type_info {
70     ($t:ty) => {
71         $crate::bindings::TypeInfo {
72             name: <$t as $crate::definitions::ObjectImpl>::TYPE_NAME.as_ptr(),
73             parent: if let Some(pname) = <$t as $crate::definitions::ObjectImpl>::PARENT_TYPE_NAME {
74                 pname.as_ptr()
75             } else {
76                 ::core::ptr::null_mut()
77             },
78             instance_size: ::core::mem::size_of::<$t>(),
79             instance_align: ::core::mem::align_of::<$t>(),
80             instance_init: <$t as $crate::definitions::ObjectImpl>::INSTANCE_INIT,
81             instance_post_init: <$t as $crate::definitions::ObjectImpl>::INSTANCE_POST_INIT,
82             instance_finalize: <$t as $crate::definitions::ObjectImpl>::INSTANCE_FINALIZE,
83             abstract_: <$t as $crate::definitions::ObjectImpl>::ABSTRACT,
84             class_size:  ::core::mem::size_of::<<$t as $crate::definitions::ObjectImpl>::Class>(),
85             class_init: <<$t as $crate::definitions::ObjectImpl>::Class as $crate::definitions::Class>::CLASS_INIT,
86             class_base_init: <<$t as $crate::definitions::ObjectImpl>::Class as $crate::definitions::Class>::CLASS_BASE_INIT,
87             class_data: ::core::ptr::null_mut(),
88             interfaces: ::core::ptr::null_mut(),
89         };
90     }
91 }
92