box_raw_ptr 2.2.0

A Rust library providing safe wrappers for working with raw pointer. These raw pointers are `*const T` and `*mut T`. These wrappers ensure memory safety by encapsulating the raw pointers in safe abstractions and providing safe methods for working with them.
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/*
*       ____             ____                 ____  __      
*      / __ )____  _  __/ __ \____ __      __/ __ \/ /______
*     / __  / __ \| |/_/ /_/ / __ `/ | /| / / /_/ / __/ ___/
*    / /_/ / /_/ />  </ _, _/ /_/ /| |/ |/ / ____/ /_/ /    
*   /_____/\____/_/|_/_/ |_|\__,_/ |__/|__/_/    \__/_/     
*                                               
*   
*   Copyright (c) 2024 Rocco Zinedine Samuel Jenson
*   
*   Licensed under the MIT License (the "License");
*   you may not use this file except in compliance with the License.
*   You may obtain a copy of the License at
*
*   https://opensource.org/licenses/MIT
*   
*   Unless required by applicable law or agreed to in writing, software
*   distributed under the License is distributed on an "AS IS" BASIS,
*   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
*   See the License for the specific language governing permissions and
*   limitations under the License.
*/

#![allow(non_camel_case_types)]
use std::alloc::{GlobalAlloc, Layout, handle_alloc_error};
use self::c_ffi::{arch_type, c_void};

/* Custom C types to remove libc dependency */
mod c_ffi {
    #[cfg(target_pointer_width = "64")]
    pub type arch_type = u64;

    #[cfg(target_pointer_width = "32")]
    pub type arch_type = u32;

    #[cfg(not(any(target_pointer_width = "32", target_pointer_width = "64")))]
    compile_error!("Unsupported target pointer width. Only 32-bit and 64-bit architectures are supported.");

    pub type c_void = std::ffi::c_void;
}

#[link(name = "allocator", kind = "static")]
extern "C" {
    fn c_global_allocator(bytes: arch_type) -> *mut c_void;
    fn c_global_deallocator(ptr: *mut u8) -> c_void;
}

pub(self) struct C_GLOBAL_ALLOCATOR;

unsafe impl GlobalAlloc for C_GLOBAL_ALLOCATOR {
    unsafe fn alloc(&self, layout: Layout) -> *mut u8 {
        let ptr: *mut u8 = c_global_allocator(layout.size() as arch_type) as *mut u8;    
        if ptr.is_null() {
            handle_alloc_error(layout);
        }
        ptr
    }

    unsafe fn dealloc(&self, ptr: *mut u8, _layout: Layout) {
        if !ptr.is_null() {
            c_global_deallocator(ptr);
        }
    }
}

/*
Note pub(self): Only lib.rs uses C_GLOBAL_ALLOCATOR to make custom C allocations,
any other allocations in user project are defined with the
#[global_allocator] attribute
*/
#[global_allocator]
pub(self) static GLOBAL: C_GLOBAL_ALLOCATOR = C_GLOBAL_ALLOCATOR;