1pub use bincode;
 2pub use serde;
 3
 4/// This is the buffer that is used Wasm side.
 5/// Note that it mirrors the functionality of
 6/// the `WasiBuffer` found in `plugin_runtime/src/plugin.rs`,
 7/// But has a few different methods.
 8pub struct __Buffer {
 9    pub ptr: u32, // *const u8,
10    pub len: u32, // usize,
11}
12
13impl __Buffer {
14    pub fn into_u64(self) -> u64 {
15        ((self.ptr as u64) << 32) | (self.len as u64)
16    }
17
18    pub fn from_u64(packed: u64) -> Self {
19        __Buffer {
20            ptr: (packed >> 32) as u32,
21            len: packed as u32,
22        }
23    }
24}
25
26/// Allocates a buffer with an exact size.
27/// We don't return the size because it has to be passed in anyway.
28#[no_mangle]
29pub extern "C" fn __alloc_buffer(len: u32) -> u32 {
30    let vec = vec![0; len as usize];
31    let buffer = unsafe { __Buffer::from_vec(vec) };
32    buffer.ptr
33}
34
35/// Frees a given buffer, requires the size.
36#[no_mangle]
37pub extern "C" fn __free_buffer(buffer: u64) {
38    let vec = unsafe { __Buffer::from_u64(buffer).to_vec() };
39    std::mem::drop(vec);
40}
41
42impl __Buffer {
43    #[inline(always)]
44    pub unsafe fn to_vec(&self) -> Vec<u8> {
45        core::slice::from_raw_parts(self.ptr as *const u8, self.len as usize).to_vec()
46    }
47
48    #[inline(always)]
49    pub unsafe fn from_vec(mut vec: Vec<u8>) -> __Buffer {
50        vec.shrink_to(0);
51        let ptr = vec.as_ptr() as u32;
52        let len = vec.len() as u32;
53        std::mem::forget(vec);
54        __Buffer { ptr, len }
55    }
56}
57
58pub mod prelude {
59    pub use super::{__Buffer, __alloc_buffer};
60    pub use plugin_macros::{export, import};
61}