gstreamer-rs/gstreamer/src/miniobject.rs
Sebastian Dröge fe1fe5b114 gstreamer: Use a reference to a pointer of correct mutability for from_glib_ptr_borrow()
This hopefully makes it easier to use and harder to get the returned
lifetime wrong.

Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer-rs/-/merge_requests/1436>
2024-04-30 15:39:15 +03:00

690 lines
25 KiB
Rust

// Take a look at the license at the top of the repository in the LICENSE file.
use std::fmt;
use crate::prelude::*;
use glib::translate::*;
pub trait IsMiniObject:
AsRef<Self::RefType> + FromGlibPtrFull<*mut Self::FfiType> + Send + Sync + 'static
{
type RefType;
type FfiType;
}
#[macro_export]
macro_rules! mini_object_wrapper (
($name:ident, $ref_name:ident, $ffi_name:path) => {
#[repr(transparent)]
pub struct $name {
obj: std::ptr::NonNull<$ffi_name>,
}
#[repr(transparent)]
pub struct $ref_name($ffi_name);
impl $crate::miniobject::IsMiniObject for $name {
type RefType = $ref_name;
type FfiType = $ffi_name;
}
impl $name {
#[inline]
pub unsafe fn from_glib_ptr_borrow(
ptr: &*mut $ffi_name,
) -> &Self {
debug_assert_eq!(std::mem::size_of::<$name>(), std::mem::size_of::<$crate::glib::ffi::gpointer>());
debug_assert!(!ptr.is_null());
&*(ptr as *const *mut $ffi_name as *const $name)
}
#[inline]
pub unsafe fn from_glib_none(ptr: *const $ffi_name) -> Self {
skip_assert_initialized!();
debug_assert!(!ptr.is_null());
$crate::ffi::gst_mini_object_ref(ptr as *mut $crate::ffi::GstMiniObject);
$name {
obj: std::ptr::NonNull::new_unchecked(ptr as *mut $ffi_name),
}
}
#[inline]
pub unsafe fn from_glib_full(ptr: *const $ffi_name) -> Self {
skip_assert_initialized!();
debug_assert!(!ptr.is_null());
$name {
obj: std::ptr::NonNull::new_unchecked(ptr as *mut $ffi_name),
}
}
#[inline]
pub unsafe fn from_glib_borrow(ptr: *const $ffi_name) -> $crate::glib::translate::Borrowed<Self> {
skip_assert_initialized!();
debug_assert!(!ptr.is_null());
$crate::glib::translate::Borrowed::new($name {
obj: std::ptr::NonNull::new_unchecked(ptr as *mut $ffi_name),
})
}
#[inline]
pub unsafe fn replace_ptr(&mut self, ptr: *mut $ffi_name) {
debug_assert!(!ptr.is_null());
self.obj = std::ptr::NonNull::new_unchecked(ptr);
}
#[inline]
#[doc(alias = "gst_mini_object_make_writable")]
pub fn make_mut(&mut self) -> &mut $ref_name {
unsafe {
if self.is_writable() {
return &mut *(self.obj.as_mut() as *mut $ffi_name as *mut $ref_name);
}
let ptr = $crate::ffi::gst_mini_object_make_writable(
self.as_mut_ptr() as *mut $crate::ffi::GstMiniObject
);
self.replace_ptr(ptr as *mut $ffi_name);
debug_assert!(self.is_writable());
&mut *(self.obj.as_mut() as *mut $ffi_name as *mut $ref_name)
}
}
#[inline]
pub fn get_mut(&mut self) -> Option<&mut $ref_name> {
if self.is_writable() {
Some(unsafe { &mut *(self.obj.as_mut() as *mut $ffi_name as *mut $ref_name) })
} else {
None
}
}
#[doc(alias = "gst_mini_object_is_writable")]
#[inline]
pub fn is_writable(&self) -> bool {
unsafe {
$crate::glib::translate::from_glib($crate::ffi::gst_mini_object_is_writable(
self.as_ptr() as *const $crate::ffi::GstMiniObject
))
}
}
#[must_use]
#[inline]
pub fn upcast(self) -> $crate::miniobject::MiniObject {
use $crate::glib::translate::IntoGlibPtr;
unsafe {
from_glib_full(self.into_glib_ptr() as *mut $crate::ffi::GstMiniObject)
}
}
}
impl $crate::glib::translate::IntoGlibPtr<*mut $ffi_name> for $name {
#[inline]
unsafe fn into_glib_ptr(self) -> *mut $ffi_name {
let s = std::mem::ManuallyDrop::new(self);
s.as_mut_ptr()
}
}
impl Clone for $name {
#[inline]
fn clone(&self) -> Self {
unsafe { $name::from_glib_none(self.as_ptr()) }
}
}
impl Drop for $name {
#[inline]
fn drop(&mut self) {
unsafe {
$crate::ffi::gst_mini_object_unref(self.as_mut_ptr() as *mut $crate::ffi::GstMiniObject);
}
}
}
impl std::ops::Deref for $name {
type Target = $ref_name;
#[inline]
fn deref(&self) -> &Self::Target {
unsafe { &*(self.obj.as_ref() as *const $ffi_name as *const $ref_name) }
}
}
impl AsRef<$ref_name> for $name {
#[inline]
fn as_ref(&self) -> &$ref_name {
&*self
}
}
impl std::borrow::Borrow<$ref_name> for $name {
#[inline]
fn borrow(&self) -> &$ref_name {
&*self
}
}
impl<'a> $crate::glib::translate::ToGlibPtr<'a, *const $ffi_name> for $name {
type Storage = std::marker::PhantomData<&'a Self>;
#[inline]
fn to_glib_none(&'a self) -> $crate::glib::translate::Stash<'a, *const $ffi_name, Self> {
$crate::glib::translate::Stash(self.as_ptr(), std::marker::PhantomData)
}
#[inline]
fn to_glib_full(&self) -> *const $ffi_name {
unsafe {
$crate::ffi::gst_mini_object_ref(self.as_mut_ptr() as *mut $crate::ffi::GstMiniObject);
self.as_ptr()
}
}
}
impl<'a> $crate::glib::translate::ToGlibPtr<'a, *mut $ffi_name> for $name {
type Storage = std::marker::PhantomData<&'a Self>;
#[inline]
fn to_glib_none(&'a self) -> $crate::glib::translate::Stash<'a, *mut $ffi_name, Self> {
$crate::glib::translate::Stash(self.as_mut_ptr(), std::marker::PhantomData)
}
#[inline]
fn to_glib_full(&self) -> *mut $ffi_name {
unsafe {
$crate::ffi::gst_mini_object_ref(self.as_mut_ptr() as *mut $crate::ffi::GstMiniObject);
self.as_mut_ptr()
}
}
}
impl<'a> $crate::glib::translate::ToGlibPtrMut<'a, *mut $ffi_name> for $name {
type Storage = std::marker::PhantomData<&'a mut Self>;
#[inline]
fn to_glib_none_mut(&'a mut self) -> $crate::glib::translate::StashMut<*mut $ffi_name, Self> {
self.make_mut();
$crate::glib::translate::StashMut(self.as_mut_ptr(), std::marker::PhantomData)
}
}
impl<'a> $crate::glib::translate::ToGlibContainerFromSlice<'a, *mut *mut $ffi_name> for $name {
#[allow(clippy::type_complexity)]
type Storage = (
std::marker::PhantomData<&'a [$name]>,
Option<Vec<*mut $ffi_name>>,
);
fn to_glib_none_from_slice(t: &'a [$name]) -> (*mut *mut $ffi_name, Self::Storage) {
skip_assert_initialized!();
let mut v_ptr = Vec::with_capacity(t.len() + 1);
unsafe {
let ptr = v_ptr.as_mut_ptr();
std::ptr::copy_nonoverlapping(t.as_ptr() as *mut *mut $ffi_name, ptr, t.len());
std::ptr::write(ptr.add(t.len()), std::ptr::null_mut());
v_ptr.set_len(t.len() + 1);
}
(v_ptr.as_ptr() as *mut *mut $ffi_name, (std::marker::PhantomData, Some(v_ptr)))
}
fn to_glib_container_from_slice(t: &'a [$name]) -> (*mut *mut $ffi_name, Self::Storage) {
skip_assert_initialized!();
let v_ptr = unsafe {
let v_ptr = $crate::glib::ffi::g_malloc(std::mem::size_of::<*mut $ffi_name>() * t.len() + 1)
as *mut *mut $ffi_name;
std::ptr::copy_nonoverlapping(t.as_ptr() as *mut *mut $ffi_name, v_ptr, t.len());
std::ptr::write(v_ptr.add(t.len()), std::ptr::null_mut());
v_ptr
};
(v_ptr, (std::marker::PhantomData, None))
}
fn to_glib_full_from_slice(t: &[$name]) -> *mut *mut $ffi_name {
skip_assert_initialized!();
unsafe {
let v_ptr = $crate::glib::ffi::g_malloc(std::mem::size_of::<*mut $ffi_name>() * t.len() + 1)
as *mut *mut $ffi_name;
for (i, s) in t.iter().enumerate() {
std::ptr::write(v_ptr.add(i), $crate::glib::translate::ToGlibPtr::to_glib_full(s));
}
std::ptr::write(v_ptr.add(t.len()), std::ptr::null_mut());
v_ptr
}
}
}
impl<'a> $crate::glib::translate::ToGlibContainerFromSlice<'a, *const *mut $ffi_name>
for $name
{
#[allow(clippy::type_complexity)]
type Storage = (
std::marker::PhantomData<&'a [$name]>,
Option<Vec<*mut $ffi_name>>,
);
fn to_glib_none_from_slice(t: &'a [$name]) -> (*const *mut $ffi_name, Self::Storage) {
skip_assert_initialized!();
let (ptr, stash) =
$crate::glib::translate::ToGlibContainerFromSlice::<'a, *mut *mut $ffi_name>::to_glib_none_from_slice(t);
(ptr as *const *mut $ffi_name, stash)
}
fn to_glib_container_from_slice(_: &'a [$name]) -> (*const *mut $ffi_name, Self::Storage) {
skip_assert_initialized!();
// Can't have consumer free a *const pointer
unimplemented!()
}
fn to_glib_full_from_slice(_: &[$name]) -> *const *mut $ffi_name {
skip_assert_initialized!();
// Can't have consumer free a *const pointer
unimplemented!()
}
}
impl $crate::glib::translate::FromGlibPtrNone<*const $ffi_name> for $name {
#[inline]
unsafe fn from_glib_none(ptr: *const $ffi_name) -> Self {
Self::from_glib_none(ptr)
}
}
impl $crate::glib::translate::FromGlibPtrNone<*mut $ffi_name> for $name {
#[inline]
unsafe fn from_glib_none(ptr: *mut $ffi_name) -> Self {
Self::from_glib_none(ptr)
}
}
impl $crate::glib::translate::FromGlibPtrFull<*const $ffi_name> for $name {
#[inline]
unsafe fn from_glib_full(ptr: *const $ffi_name) -> Self {
Self::from_glib_full(ptr)
}
}
impl $crate::glib::translate::FromGlibPtrFull<*mut $ffi_name> for $name {
#[inline]
unsafe fn from_glib_full(ptr: *mut $ffi_name) -> Self {
Self::from_glib_full(ptr)
}
}
impl $crate::glib::translate::FromGlibPtrBorrow<*const $ffi_name> for $name {
#[inline]
unsafe fn from_glib_borrow(ptr: *const $ffi_name) -> $crate::glib::translate::Borrowed<Self> {
Self::from_glib_borrow(ptr)
}
}
impl $crate::glib::translate::FromGlibPtrBorrow<*mut $ffi_name> for $name {
#[inline]
unsafe fn from_glib_borrow(ptr: *mut $ffi_name) -> $crate::glib::translate::Borrowed<Self> {
Self::from_glib_borrow(ptr)
}
}
impl $crate::glib::translate::FromGlibContainerAsVec<*mut $ffi_name, *mut *mut $ffi_name>
for $name
{
unsafe fn from_glib_none_num_as_vec(ptr: *mut *mut $ffi_name, num: usize) -> Vec<Self> {
if num == 0 || ptr.is_null() {
return Vec::new();
}
let mut res = Vec::<Self>::with_capacity(num);
let res_ptr = res.as_mut_ptr();
for i in 0..num {
::std::ptr::write(res_ptr.add(i), $crate::glib::translate::from_glib_none(std::ptr::read(ptr.add(i))));
}
res.set_len(num);
res
}
unsafe fn from_glib_container_num_as_vec(ptr: *mut *mut $ffi_name, num: usize) -> Vec<Self> {
let res = $crate::glib::translate::FromGlibContainerAsVec::from_glib_none_num_as_vec(ptr, num);
$crate::glib::ffi::g_free(ptr as *mut _);
res
}
unsafe fn from_glib_full_num_as_vec(ptr: *mut *mut $ffi_name, num: usize) -> Vec<Self> {
if num == 0 || ptr.is_null() {
return Vec::new();
}
let mut res = Vec::with_capacity(num);
let res_ptr = res.as_mut_ptr();
::std::ptr::copy_nonoverlapping(ptr as *mut Self, res_ptr, num);
res.set_len(num);
$crate::glib::ffi::g_free(ptr as *mut _);
res
}
}
impl $crate::glib::translate::FromGlibPtrArrayContainerAsVec<*mut $ffi_name, *mut *mut $ffi_name>
for $name
{
unsafe fn from_glib_none_as_vec(ptr: *mut *mut $ffi_name) -> Vec<Self> {
$crate::glib::translate::FromGlibContainerAsVec::from_glib_none_num_as_vec(ptr, glib::translate::c_ptr_array_len(ptr))
}
unsafe fn from_glib_container_as_vec(ptr: *mut *mut $ffi_name) -> Vec<Self> {
$crate::glib::translate::FromGlibContainerAsVec::from_glib_container_num_as_vec(ptr, glib::translate::c_ptr_array_len(ptr))
}
unsafe fn from_glib_full_as_vec(ptr: *mut *mut $ffi_name) -> Vec<Self> {
$crate::glib::translate::FromGlibContainerAsVec::from_glib_full_num_as_vec(ptr, glib::translate::c_ptr_array_len(ptr))
}
}
impl $crate::glib::translate::FromGlibContainerAsVec<*mut $ffi_name, *const *mut $ffi_name>
for $name
{
unsafe fn from_glib_none_num_as_vec(ptr: *const *mut $ffi_name, num: usize) -> Vec<Self> {
$crate::glib::translate::FromGlibContainerAsVec::from_glib_none_num_as_vec(ptr as *mut *mut _, num)
}
unsafe fn from_glib_container_num_as_vec(_: *const *mut $ffi_name, _: usize) -> Vec<Self> {
// Can't free a *const
unimplemented!()
}
unsafe fn from_glib_full_num_as_vec(_: *const *mut $ffi_name, _: usize) -> Vec<Self> {
// Can't free a *const
unimplemented!()
}
}
impl $crate::glib::translate::FromGlibPtrArrayContainerAsVec<*mut $ffi_name, *const *mut $ffi_name> for $name
{
unsafe fn from_glib_none_as_vec(ptr: *const *mut $ffi_name) -> Vec<Self> {
$crate::glib::translate::FromGlibPtrArrayContainerAsVec::from_glib_none_as_vec(ptr as *mut *mut _)
}
unsafe fn from_glib_container_as_vec(_: *const *mut $ffi_name) -> Vec<Self> {
// Can't free a *const
unimplemented!()
}
unsafe fn from_glib_full_as_vec(_: *const *mut $ffi_name) -> Vec<Self> {
// Can't free a *const
unimplemented!()
}
}
impl $crate::glib::translate::GlibPtrDefault for $name {
type GlibType = *mut $ffi_name;
}
unsafe impl $crate::glib::translate::TransparentPtrType for $name {}
impl $ref_name {
#[inline]
pub fn as_ptr(&self) -> *const $ffi_name {
self as *const Self as *const $ffi_name
}
#[inline]
pub fn as_mut_ptr(&self) -> *mut $ffi_name {
self as *const Self as *mut $ffi_name
}
#[inline]
pub unsafe fn from_ptr<'a>(ptr: *const $ffi_name) -> &'a Self {
debug_assert!(!ptr.is_null());
&*(ptr as *const Self)
}
#[inline]
pub unsafe fn from_mut_ptr<'a>(ptr: *mut $ffi_name) -> &'a mut Self {
debug_assert!(!ptr.is_null());
debug_assert_ne!(
$crate::ffi::gst_mini_object_is_writable(ptr as *mut $crate::ffi::GstMiniObject),
$crate::glib::ffi::GFALSE
);
&mut *(ptr as *mut Self)
}
#[doc(alias = "gst_mini_object_copy")]
#[inline]
pub fn copy(&self) -> $name {
unsafe {
$name::from_glib_full($crate::ffi::gst_mini_object_copy(
self.as_ptr() as *const $crate::ffi::GstMiniObject
) as *const $ffi_name)
}
}
#[inline]
pub fn upcast_ref(&self) -> &$crate::miniobject::MiniObjectRef {
unsafe {
&*(self.as_ptr() as *const $crate::miniobject::MiniObjectRef)
}
}
#[inline]
pub fn upcast_mut(&mut self) -> &mut $crate::miniobject::MiniObjectRef {
unsafe {
&mut *(self.as_mut_ptr() as *mut $crate::miniobject::MiniObjectRef)
}
}
#[inline]
pub fn ptr_eq(this: &$ref_name, other: &$ref_name) -> bool {
skip_assert_initialized!();
this.as_ptr() == other.as_ptr()
}
}
impl $crate::glib::translate::GlibPtrDefault for $ref_name {
type GlibType = *mut $ffi_name;
}
impl ToOwned for $ref_name {
type Owned = $name;
#[inline]
fn to_owned(&self) -> $name {
self.copy()
}
}
unsafe impl Sync for $ref_name {}
unsafe impl Send for $ref_name {}
unsafe impl Sync for $name {}
unsafe impl Send for $name {}
};
($name:ident, $ref_name:ident, $ffi_name:path, $get_type:expr) => {
$crate::mini_object_wrapper!($name, $ref_name, $ffi_name);
impl $crate::glib::types::StaticType for $name {
#[inline]
fn static_type() -> $crate::glib::types::Type {
$ref_name::static_type()
}
}
#[allow(clippy::redundant_closure_call)]
impl $crate::glib::types::StaticType for $ref_name {
#[inline]
fn static_type() -> $crate::glib::types::Type {
unsafe { $crate::glib::translate::from_glib($get_type()) }
}
}
impl glib::value::ValueType for $name {
type Type = Self;
}
impl glib::value::ValueTypeOptional for $name { }
unsafe impl<'a> $crate::glib::value::FromValue<'a> for $name {
type Checker = $crate::glib::value::GenericValueTypeOrNoneChecker<Self>;
#[inline]
unsafe fn from_value(value: &'a $crate::glib::Value) -> Self {
skip_assert_initialized!();
$crate::glib::translate::from_glib_none(
$crate::glib::gobject_ffi::g_value_get_boxed($crate::glib::translate::ToGlibPtr::to_glib_none(value).0) as *mut $ffi_name
)
}
}
unsafe impl<'a> $crate::glib::value::FromValue<'a> for &'a $name {
type Checker = $crate::glib::value::GenericValueTypeOrNoneChecker<Self>;
#[inline]
unsafe fn from_value(value: &'a $crate::glib::Value) -> Self {
skip_assert_initialized!();
let value = &*(value as *const $crate::glib::Value as *const $crate::glib::gobject_ffi::GValue);
$name::from_glib_ptr_borrow(&*(&value.data[0].v_pointer as *const $crate::glib::ffi::gpointer as *const *mut $ffi_name))
}
}
impl $crate::glib::value::ToValue for $name {
#[inline]
fn to_value(&self) -> $crate::glib::Value {
let mut value = $crate::glib::Value::for_value_type::<Self>();
unsafe {
$crate::glib::gobject_ffi::g_value_set_boxed(
$crate::glib::translate::ToGlibPtrMut::to_glib_none_mut(&mut value).0,
$crate::glib::translate::ToGlibPtr::<*const $ffi_name>::to_glib_none(self).0 as *mut _,
)
}
value
}
#[inline]
fn value_type(&self) -> $crate::glib::Type {
<Self as $crate::glib::prelude::StaticType>::static_type()
}
}
impl $crate::glib::value::ToValueOptional for $name {
#[inline]
fn to_value_optional(s: Option<&Self>) -> $crate::glib::Value {
skip_assert_initialized!();
let mut value = $crate::glib::Value::for_value_type::<Self>();
unsafe {
$crate::glib::gobject_ffi::g_value_set_boxed(
$crate::glib::translate::ToGlibPtrMut::to_glib_none_mut(&mut value).0,
$crate::glib::translate::ToGlibPtr::<*const $ffi_name>::to_glib_none(&s).0 as *mut _,
)
}
value
}
}
impl From<$name> for $crate::glib::Value {
#[inline]
fn from(v: $name) -> $crate::glib::Value {
skip_assert_initialized!();
let mut value = $crate::glib::Value::for_value_type::<$name>();
unsafe {
$crate::glib::gobject_ffi::g_value_take_boxed(
$crate::glib::translate::ToGlibPtrMut::to_glib_none_mut(&mut value).0,
$crate::glib::translate::IntoGlibPtr::<*mut $ffi_name>::into_glib_ptr(v) as *mut _,
)
}
value
}
}
unsafe impl<'a> $crate::glib::value::FromValue<'a> for &'a $ref_name {
type Checker = $crate::glib::value::GenericValueTypeOrNoneChecker<Self>;
#[inline]
unsafe fn from_value(value: &'a $crate::glib::Value) -> Self {
skip_assert_initialized!();
&*($crate::glib::gobject_ffi::g_value_get_boxed($crate::glib::translate::ToGlibPtr::to_glib_none(value).0) as *const $ref_name)
}
}
// Can't have SetValue/SetValueOptional impls as otherwise one could use it to get
// immutable references from a mutable reference without borrowing via the value
impl $crate::glib::prelude::HasParamSpec for $name {
type ParamSpec = $crate::glib::ParamSpecBoxed;
type SetValue = Self;
type BuilderFn = fn(&str) -> $crate::glib::ParamSpecBoxedBuilder<Self>;
fn param_spec_builder() -> Self::BuilderFn {
|name| Self::ParamSpec::builder(name)
}
}
};
);
#[cfg(not(any(feature = "v1_20", docsrs)))]
mini_object_wrapper!(MiniObject, MiniObjectRef, ffi::GstMiniObject);
#[cfg(feature = "v1_20")]
mini_object_wrapper!(MiniObject, MiniObjectRef, ffi::GstMiniObject, || {
ffi::gst_mini_object_get_type()
});
impl MiniObject {
#[inline]
pub fn downcast<T: IsMiniObject + StaticType>(self) -> Result<T, Self> {
if self.type_().is_a(T::static_type()) {
unsafe { Ok(from_glib_full(self.into_glib_ptr() as *mut T::FfiType)) }
} else {
Err(self)
}
}
}
impl fmt::Debug for MiniObject {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
self.as_ref().fmt(f)
}
}
impl fmt::Debug for MiniObjectRef {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
f.debug_struct("MiniObject")
.field("ptr", &self.as_ptr())
.field("type", &self.type_())
.finish()
}
}
impl MiniObjectRef {
#[inline]
pub fn type_(&self) -> glib::Type {
unsafe { from_glib((*self.as_ptr()).type_) }
}
#[inline]
pub fn downcast_ref<T: IsMiniObject + StaticType>(&self) -> Option<&T::RefType> {
if self.type_().is_a(T::static_type()) {
unsafe { Some(&*(self as *const Self as *const T::RefType)) }
} else {
None
}
}
#[inline]
pub fn downcast_mut<T: IsMiniObject + StaticType>(&mut self) -> Option<&mut T::RefType> {
if self.type_().is_a(T::static_type()) {
unsafe { Some(&mut *(self as *mut Self as *mut T::RefType)) }
} else {
None
}
}
}