| #![cfg(feature = "alloc")] |
| #![allow(missing_docs)] |
| |
| use crate::rust_string::RustString; |
| use alloc::string::String; |
| use alloc::vec::Vec; |
| use core::ffi::c_void; |
| use core::marker::PhantomData; |
| use core::mem::{self, ManuallyDrop, MaybeUninit}; |
| use core::ptr; |
| |
| // ABI compatible with C++ rust::Vec<T> (not necessarily alloc::vec::Vec<T>). |
| #[repr(C)] |
| pub struct RustVec<T> { |
| repr: [MaybeUninit<usize>; mem::size_of::<Vec<c_void>>() / mem::size_of::<usize>()], |
| marker: PhantomData<Vec<T>>, |
| } |
| |
| impl<T> RustVec<T> { |
| pub fn new() -> Self { |
| Self::from(Vec::new()) |
| } |
| |
| pub fn from(v: Vec<T>) -> Self { |
| unsafe { mem::transmute::<Vec<T>, RustVec<T>>(v) } |
| } |
| |
| pub fn from_ref(v: &Vec<T>) -> &Self { |
| unsafe { &*(v as *const Vec<T> as *const RustVec<T>) } |
| } |
| |
| pub fn from_mut(v: &mut Vec<T>) -> &mut Self { |
| unsafe { &mut *(v as *mut Vec<T> as *mut RustVec<T>) } |
| } |
| |
| pub fn into_vec(self) -> Vec<T> { |
| unsafe { mem::transmute::<RustVec<T>, Vec<T>>(self) } |
| } |
| |
| pub fn as_vec(&self) -> &Vec<T> { |
| unsafe { &*(self as *const RustVec<T> as *const Vec<T>) } |
| } |
| |
| pub fn as_mut_vec(&mut self) -> &mut Vec<T> { |
| unsafe { &mut *(self as *mut RustVec<T> as *mut Vec<T>) } |
| } |
| |
| pub fn len(&self) -> usize { |
| self.as_vec().len() |
| } |
| |
| pub fn capacity(&self) -> usize { |
| self.as_vec().capacity() |
| } |
| |
| pub fn as_ptr(&self) -> *const T { |
| self.as_vec().as_ptr() |
| } |
| |
| pub fn reserve_total(&mut self, new_cap: usize) { |
| let vec = self.as_mut_vec(); |
| if new_cap > vec.capacity() { |
| let additional = new_cap - vec.len(); |
| vec.reserve(additional); |
| } |
| } |
| |
| pub unsafe fn set_len(&mut self, len: usize) { |
| unsafe { self.as_mut_vec().set_len(len) } |
| } |
| |
| pub fn truncate(&mut self, len: usize) { |
| self.as_mut_vec().truncate(len); |
| } |
| } |
| |
| impl RustVec<RustString> { |
| pub fn from_vec_string(v: Vec<String>) -> Self { |
| let mut v = ManuallyDrop::new(v); |
| let ptr = v.as_mut_ptr().cast::<RustString>(); |
| let len = v.len(); |
| let cap = v.capacity(); |
| Self::from(unsafe { Vec::from_raw_parts(ptr, len, cap) }) |
| } |
| |
| pub fn from_ref_vec_string(v: &Vec<String>) -> &Self { |
| Self::from_ref(unsafe { &*(v as *const Vec<String> as *const Vec<RustString>) }) |
| } |
| |
| pub fn from_mut_vec_string(v: &mut Vec<String>) -> &mut Self { |
| Self::from_mut(unsafe { &mut *(v as *mut Vec<String> as *mut Vec<RustString>) }) |
| } |
| |
| pub fn into_vec_string(self) -> Vec<String> { |
| let mut v = ManuallyDrop::new(self.into_vec()); |
| let ptr = v.as_mut_ptr().cast::<String>(); |
| let len = v.len(); |
| let cap = v.capacity(); |
| unsafe { Vec::from_raw_parts(ptr, len, cap) } |
| } |
| |
| pub fn as_vec_string(&self) -> &Vec<String> { |
| unsafe { &*(self as *const RustVec<RustString> as *const Vec<String>) } |
| } |
| |
| pub fn as_mut_vec_string(&mut self) -> &mut Vec<String> { |
| unsafe { &mut *(self as *mut RustVec<RustString> as *mut Vec<String>) } |
| } |
| } |
| |
| impl<T> Drop for RustVec<T> { |
| fn drop(&mut self) { |
| unsafe { ptr::drop_in_place(self.as_mut_vec()) } |
| } |
| } |