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#![doc(html_root_url = "https://docs.rs/wasm_plugin_guest/0.1.5")]
#![deny(missing_docs)]
use std::mem::ManuallyDrop;
mod serialization;
pub use wasm_plugin_guest_derive::{export_function, import_functions};
bitfield::bitfield! {
#[doc(hidden)]
pub struct FatPointer(u64);
u32;
#[doc(hidden)]
pub ptr, set_ptr: 31, 0;
#[doc(hidden)]
pub len, set_len: 63, 32;
}
pub fn read_message<T: serialization::Deserializable>(ptr: usize, len: usize) -> T {
let buf = unsafe { std::slice::from_raw_parts(ptr as *const u8, len as usize) };
T::deserialize(buf)
}
pub fn write_message<U>(message: &U) -> (usize, usize)
where
U: serialization::Serializable,
{
let message: Vec<u8> = message.serialize();
let local_len = message.len();
(
ManuallyDrop::new(message).as_mut_ptr() as *const usize as usize,
local_len,
)
}
#[cfg(feature = "inject_getrandom")]
mod getrandom_shim {
use getrandom::register_custom_getrandom;
use getrandom::Error;
extern "C" {
fn __getrandom(ptr: u32, len: u32);
}
#[allow(clippy::unnecessary_wraps)]
fn external_getrandom(buf: &mut [u8]) -> Result<(), Error> {
let len = buf.len();
let ptr = buf.as_ptr();
unsafe {
__getrandom(ptr as u32, len as u32);
}
Ok(())
}
register_custom_getrandom!(external_getrandom);
}
#[no_mangle]
pub extern "C" fn allocate_message_buffer(len: u32) -> u32 {
let mut buffer: ManuallyDrop<Vec<u8>> = ManuallyDrop::new(Vec::with_capacity(len as usize));
buffer.as_mut_ptr() as *const u32 as u32
}
#[no_mangle]
pub extern "C" fn free_message_buffer(ptr: u32, len: u32) {
unsafe { drop(Vec::from_raw_parts(ptr as *mut u8, 0, len as usize)) }
}