Add CxxVector::push in Rust
diff --git a/src/cxx.cc b/src/cxx.cc
index c0ef738..f1b8ad8 100644
--- a/src/cxx.cc
+++ b/src/cxx.cc
@@ -427,6 +427,13 @@
} // namespace cxxbridge1
} // namespace rust
+namespace {
+template <typename T>
+void destroy(T *ptr) {
+ ptr->~T();
+}
+} // namespace
+
extern "C" {
void cxxbridge1$unique_ptr$std$string$null(
std::unique_ptr<std::string> *ptr) noexcept {
@@ -491,6 +498,13 @@
ptr->~unique_ptr(); \
}
+#define STD_VECTOR_TRIVIAL_OPS(RUST_TYPE, CXX_TYPE) \
+ void cxxbridge1$std$vector$##RUST_TYPE##$push_back( \
+ std::vector<CXX_TYPE> *v, CXX_TYPE *value) noexcept { \
+ v->push_back(std::move(*value)); \
+ destroy(value); \
+ }
+
#define RUST_VEC_EXTERNS(RUST_TYPE, CXX_TYPE) \
void cxxbridge1$rust_vec$##RUST_TYPE##$new( \
rust::Vec<CXX_TYPE> *ptr) noexcept; \
@@ -603,10 +617,13 @@
MACRO(f32, float) \
MACRO(f64, double)
-#define FOR_EACH_STD_VECTOR(MACRO) \
+#define FOR_EACH_TRIVIAL_STD_VECTOR(MACRO) \
FOR_EACH_NUMERIC(MACRO) \
MACRO(usize, std::size_t) \
- MACRO(isize, rust::isize) \
+ MACRO(isize, rust::isize)
+
+#define FOR_EACH_STD_VECTOR(MACRO) \
+ FOR_EACH_TRIVIAL_STD_VECTOR(MACRO) \
MACRO(string, std::string)
#define FOR_EACH_RUST_VEC(MACRO) \
@@ -627,6 +644,7 @@
extern "C" {
FOR_EACH_STD_VECTOR(STD_VECTOR_OPS)
+FOR_EACH_TRIVIAL_STD_VECTOR(STD_VECTOR_TRIVIAL_OPS)
FOR_EACH_RUST_VEC(RUST_VEC_EXTERNS)
FOR_EACH_SHARED_PTR(SHARED_PTR_OPS)
} // extern "C"
diff --git a/src/cxx_vector.rs b/src/cxx_vector.rs
index 1643341..23f7621 100644
--- a/src/cxx_vector.rs
+++ b/src/cxx_vector.rs
@@ -8,7 +8,7 @@
use core::fmt::{self, Debug};
use core::iter::FusedIterator;
use core::marker::{PhantomData, PhantomPinned};
-use core::mem;
+use core::mem::{self, ManuallyDrop};
use core::pin::Pin;
use core::ptr;
use core::slice;
@@ -146,6 +146,22 @@
pub fn iter_mut(self: Pin<&mut Self>) -> IterMut<T> {
IterMut { v: self, index: 0 }
}
+
+ /// Appends an element to the back of the vector.
+ ///
+ /// Matches the behavior of C++ [std::vector\<T\>::push_back][push_back].
+ ///
+ /// [push_back]: https://en.cppreference.com/w/cpp/container/vector/push_back
+ pub fn push(self: Pin<&mut Self>, value: T)
+ where
+ T: ExternType<Kind = Trivial>,
+ {
+ let mut value = ManuallyDrop::new(value);
+ unsafe {
+ // C++ calls move constructor followed by destructor on `value`.
+ T::__push_back(self, &mut value);
+ }
+ }
}
/// Iterator over elements of a `CxxVector` by shared reference.
@@ -296,6 +312,14 @@
#[doc(hidden)]
unsafe fn __get_unchecked(v: *mut CxxVector<Self>, pos: usize) -> *mut Self;
#[doc(hidden)]
+ unsafe fn __push_back(v: Pin<&mut CxxVector<Self>>, value: &mut ManuallyDrop<Self>) {
+ // Opaque C type vector elements do not get this method because they can
+ // never exist by value on the Rust side of the bridge.
+ let _ = v;
+ let _ = value;
+ unreachable!()
+ }
+ #[doc(hidden)]
fn __unique_ptr_null() -> *mut c_void;
#[doc(hidden)]
unsafe fn __unique_ptr_raw(raw: *mut CxxVector<Self>) -> *mut c_void;
@@ -307,8 +331,24 @@
unsafe fn __unique_ptr_drop(repr: *mut c_void);
}
+macro_rules! vector_element_push_back {
+ (opaque, $segment:expr, $ty:ty) => {};
+ (trivial, $segment:expr, $ty:ty) => {
+ #[doc(hidden)]
+ unsafe fn __push_back(v: Pin<&mut CxxVector<$ty>>, value: &mut ManuallyDrop<$ty>) {
+ extern "C" {
+ attr! {
+ #[link_name = concat!("cxxbridge1$std$vector$", $segment, "$push_back")]
+ fn __push_back(_: Pin<&mut CxxVector<$ty>>, _: &mut ManuallyDrop<$ty>);
+ }
+ }
+ __push_back(v, value);
+ }
+ };
+}
+
macro_rules! impl_vector_element {
- ($segment:expr, $name:expr, $ty:ty) => {
+ ($kind:ident, $segment:expr, $name:expr, $ty:ty) => {
const_assert_eq!(1, mem::align_of::<CxxVector<$ty>>());
unsafe impl VectorElement for $ty {
@@ -336,6 +376,7 @@
}
__get_unchecked(v, pos)
}
+ vector_element_push_back!($kind, $segment, $ty);
#[doc(hidden)]
fn __unique_ptr_null() -> *mut c_void {
extern "C" {
@@ -396,7 +437,7 @@
macro_rules! impl_vector_element_for_primitive {
($ty:ident) => {
- impl_vector_element!(stringify!($ty), stringify!($ty), $ty);
+ impl_vector_element!(trivial, stringify!($ty), stringify!($ty), $ty);
};
}
@@ -413,4 +454,4 @@
impl_vector_element_for_primitive!(f32);
impl_vector_element_for_primitive!(f64);
-impl_vector_element!("string", "CxxString", CxxString);
+impl_vector_element!(opaque, "string", "CxxString", CxxString);