wasmer/lib/runtime-c-api/src/trampoline.rs

85 lines
2.8 KiB
Rust

//! Trampoline emitter for transforming function calls.
use std::ffi::c_void;
use std::mem;
use wasmer_runtime_core::trampoline::*;
#[repr(C)]
pub struct wasmer_trampoline_buffer_builder_t;
#[repr(C)]
pub struct wasmer_trampoline_buffer_t;
#[repr(C)]
pub struct wasmer_trampoline_callable_t;
/// Creates a new trampoline builder.
#[no_mangle]
#[allow(clippy::cast_ptr_alignment)]
pub extern "C" fn wasmer_trampoline_buffer_builder_new() -> *mut wasmer_trampoline_buffer_builder_t
{
Box::into_raw(Box::new(TrampolineBufferBuilder::new())) as *mut _
}
/// Adds a context trampoline to the builder.
#[no_mangle]
#[allow(clippy::cast_ptr_alignment)]
pub unsafe extern "C" fn wasmer_trampoline_buffer_builder_add_context_trampoline(
builder: *mut wasmer_trampoline_buffer_builder_t,
func: *const wasmer_trampoline_callable_t,
ctx: *const c_void,
) -> usize {
let builder = &mut *(builder as *mut TrampolineBufferBuilder);
builder.add_context_trampoline(func as *const CallTarget, ctx as *const CallContext)
}
/// Adds a callinfo trampoline to the builder.
#[no_mangle]
#[allow(clippy::cast_ptr_alignment)]
pub unsafe extern "C" fn wasmer_trampoline_buffer_builder_add_callinfo_trampoline(
builder: *mut wasmer_trampoline_buffer_builder_t,
func: *const wasmer_trampoline_callable_t,
ctx: *const c_void,
num_params: u32,
) -> usize {
let builder = &mut *(builder as *mut TrampolineBufferBuilder);
builder.add_callinfo_trampoline(mem::transmute(func), ctx as *const CallContext, num_params)
}
/// Finalizes the trampoline builder into an executable buffer.
#[no_mangle]
#[allow(clippy::cast_ptr_alignment)]
pub unsafe extern "C" fn wasmer_trampoline_buffer_builder_build(
builder: *mut wasmer_trampoline_buffer_builder_t,
) -> *mut wasmer_trampoline_buffer_t {
let builder = Box::from_raw(builder as *mut TrampolineBufferBuilder);
Box::into_raw(Box::new(builder.build())) as *mut _
}
/// Destroys the trampoline buffer if not null.
#[no_mangle]
#[allow(clippy::cast_ptr_alignment)]
pub unsafe extern "C" fn wasmer_trampoline_buffer_destroy(buffer: *mut wasmer_trampoline_buffer_t) {
if !buffer.is_null() {
Box::from_raw(buffer);
}
}
/// Returns the callable pointer for the trampoline with index `idx`.
#[no_mangle]
#[allow(clippy::cast_ptr_alignment)]
pub unsafe extern "C" fn wasmer_trampoline_buffer_get_trampoline(
buffer: *const wasmer_trampoline_buffer_t,
idx: usize,
) -> *const wasmer_trampoline_callable_t {
let buffer = &*(buffer as *const TrampolineBuffer);
buffer.get_trampoline(idx) as _
}
/// Returns the context added by `add_context_trampoline`, from within the callee function.
#[no_mangle]
#[allow(clippy::cast_ptr_alignment)]
pub unsafe extern "C" fn wasmer_trampoline_get_context() -> *mut c_void {
get_context() as *const c_void as *mut c_void
}