wasmer/lib/emscripten/src/utils.rs

163 lines
5.1 KiB
Rust
Raw Normal View History

2019-01-23 07:27:13 +00:00
use wasmer_runtime_core::{module::Module, vm::Ctx};
//use wasmer_runtime_core::Instance;
2019-01-11 05:37:59 +00:00
use super::env;
2018-11-27 04:29:26 +00:00
use libc::stat;
2018-12-09 07:02:26 +00:00
use std::ffi::CStr;
2018-11-26 21:15:49 +00:00
use std::os::raw::c_char;
2018-11-27 04:28:13 +00:00
use std::slice;
/// We check if a provided module is an Emscripten generated one
pub fn is_emscripten_module(module: &Module) -> bool {
2019-01-18 06:18:13 +00:00
for (_, import_name) in &module.0.imported_functions {
if import_name.name == "_emscripten_memcpy_big" && import_name.namespace == "env" {
return true;
}
}
false
}
2019-01-23 07:27:13 +00:00
pub unsafe fn write_to_buf(string: *const c_char, buf: u32, max: u32, vmctx: &mut Ctx) -> u32 {
let buf_addr = vmctx.memory(0)[buf as usize] as *mut c_char;
2018-12-11 17:06:20 +00:00
2018-12-14 01:58:08 +00:00
for i in 0..max {
*buf_addr.add(i as _) = *string.add(i as _);
2018-12-11 17:06:20 +00:00
}
buf
}
2018-12-13 23:09:07 +00:00
/// This function expects nullbyte to be appended.
2019-01-23 07:27:13 +00:00
pub unsafe fn copy_cstr_into_wasm(vmctx: &mut Ctx, cstr: *const c_char) -> u32 {
2018-12-07 03:08:17 +00:00
let s = CStr::from_ptr(cstr).to_str().unwrap();
let cstr_len = s.len();
2019-01-23 07:27:13 +00:00
let space_offset = env::call_malloc((cstr_len as i32) + 1, vmctx);
let raw_memory = vmctx.memory(0)[space_offset as usize] as *mut u8;
2018-12-07 03:08:17 +00:00
let slice = slice::from_raw_parts_mut(raw_memory, cstr_len);
for (byte, loc) in s.bytes().zip(slice.iter_mut()) {
*loc = byte;
}
2018-12-07 13:50:35 +00:00
// TODO: Appending null byte won't work, because there is CStr::from_ptr(cstr)
// at the top that crashes when there is no null byte
2018-12-07 03:08:17 +00:00
*raw_memory.add(cstr_len) = 0;
space_offset
}
2019-01-23 07:27:13 +00:00
pub unsafe fn allocate_on_stack<'a, T: Copy>(count: u32, vmctx: &'a Ctx) -> (u32, &'a mut [T]) {
unimplemented!("allocate_on_stack not implemented")
2019-01-18 06:18:13 +00:00
// let offset = (instance.emscripten_data().as_ref().unwrap().stack_alloc)(
// count * (size_of::<T>() as u32),
2019-01-23 07:27:13 +00:00
// vmctx,
2019-01-18 06:18:13 +00:00
// );
2019-01-23 07:27:13 +00:00
// let addr = vmctx.memory(0)[offset as usize] as *mut T;
2019-01-18 06:18:13 +00:00
// let slice = slice::from_raw_parts_mut(addr, count as usize);
//
// (offset, slice)
2018-12-07 03:40:44 +00:00
}
2019-01-23 07:27:13 +00:00
pub unsafe fn allocate_cstr_on_stack<'a>(s: &str, vmctx: &'a Ctx) -> (u32, &'a [u8]) {
let (offset, slice) = allocate_on_stack((s.len() + 1) as u32, vmctx);
2018-12-07 03:40:44 +00:00
use std::iter;
for (byte, loc) in s.bytes().chain(iter::once(0)).zip(slice.iter_mut()) {
*loc = byte;
}
(offset, slice)
}
2019-01-23 07:27:13 +00:00
pub unsafe fn copy_terminated_array_of_cstrs(_vmctx: &mut Ctx, cstrs: *mut *mut c_char) -> u32 {
2018-11-26 21:15:49 +00:00
let total_num = {
let mut ptr = cstrs;
let mut counter = 0;
while !(*ptr).is_null() {
counter += 1;
ptr = ptr.add(1);
}
counter
};
2018-11-27 04:29:26 +00:00
debug!(
"emscripten::copy_terminated_array_of_cstrs::total_num: {}",
total_num
);
2018-11-26 21:15:49 +00:00
0
}
#[repr(C)]
pub struct GuestStat {
2019-01-04 02:39:07 +00:00
st_dev: u32,
2018-12-31 17:31:23 +00:00
__st_dev_padding: u32,
__st_ino_truncated: u32,
st_mode: u32,
st_nlink: u32,
st_uid: u32,
st_gid: u32,
2018-12-31 17:31:23 +00:00
st_rdev: u32,
__st_rdev_padding: u32,
st_size: u32,
st_blksize: u32,
st_blocks: u32,
st_atime: u64,
st_mtime: u64,
st_ctime: u64,
2018-12-31 17:31:23 +00:00
st_ino: u64,
}
2019-01-18 06:33:46 +00:00
#[allow(clippy::cast_ptr_alignment)]
2019-01-23 07:27:13 +00:00
pub unsafe fn copy_stat_into_wasm(vmctx: &mut Ctx, buf: u32, stat: &stat) {
let stat_ptr = vmctx.memory(0)[buf as usize] as *mut GuestStat;
(*stat_ptr).st_dev = stat.st_dev as _;
2018-12-31 17:31:23 +00:00
(*stat_ptr).__st_dev_padding = 0;
(*stat_ptr).__st_ino_truncated = stat.st_ino as _;
(*stat_ptr).st_mode = stat.st_mode as _;
(*stat_ptr).st_nlink = stat.st_nlink as _;
(*stat_ptr).st_uid = stat.st_uid as _;
(*stat_ptr).st_gid = stat.st_gid as _;
(*stat_ptr).st_rdev = stat.st_rdev as _;
2018-12-31 17:31:23 +00:00
(*stat_ptr).__st_rdev_padding = 0;
(*stat_ptr).st_size = stat.st_size as _;
2018-12-31 15:15:24 +00:00
(*stat_ptr).st_blksize = 4096;
#[cfg(not(target_os = "windows"))]
{
(*stat_ptr).st_blocks = stat.st_blocks as _;
}
2018-12-31 15:15:24 +00:00
#[cfg(target_os = "windows")]
{
(*stat_ptr).st_blocks = 0;
}
(*stat_ptr).st_atime = stat.st_atime as _;
(*stat_ptr).st_mtime = stat.st_mtime as _;
(*stat_ptr).st_ctime = stat.st_ctime as _;
2018-12-31 17:31:23 +00:00
(*stat_ptr).st_ino = stat.st_ino as _;
}
#[cfg(test)]
mod tests {
2018-11-22 04:59:23 +00:00
use super::is_emscripten_module;
2019-01-18 00:25:05 +00:00
use std::sync::Arc;
2019-01-18 06:18:13 +00:00
use wabt::wat2wasm;
use wasmer_clif_backend::CraneliftCompiler;
2019-01-23 07:27:13 +00:00
use wasmer_runtime_core::{compile_with, module::Module};
#[test]
fn should_detect_emscripten_files() {
2019-01-11 05:37:59 +00:00
const wast_bytes: &[u8] = include_bytes!("tests/is_emscripten_true.wast");
let wasm_binary = wat2wasm(wast_bytes.to_vec()).expect("Can't convert to wasm");
2019-01-23 20:35:14 +00:00
let module = compile_with(&wasm_binary[..], &CraneliftCompiler::new())
.expect("WASM can't be compiled");
2019-01-18 00:25:05 +00:00
let module = Arc::new(module);
assert!(is_emscripten_module(&module));
}
#[test]
fn should_detect_non_emscripten_files() {
2019-01-11 05:37:59 +00:00
const wast_bytes: &[u8] = include_bytes!("tests/is_emscripten_false.wast");
let wasm_binary = wat2wasm(wast_bytes.to_vec()).expect("Can't convert to wasm");
2019-01-23 20:35:14 +00:00
let module = compile_with(&wasm_binary[..], &CraneliftCompiler::new())
.expect("WASM can't be compiled");
2019-01-18 00:25:05 +00:00
let module = Arc::new(module);
assert!(!is_emscripten_module(&module));
}
2018-11-22 04:59:23 +00:00
}