wasmer/src/webassembly/mod.rs

pub mod errors;
pub mod utils;
pub mod module;
pub mod memory;
pub mod instance;

use std::str::FromStr;
use std::time::{Duration, Instant};
use std::panic;
use std::ptr;
use cranelift_native;
use target_lexicon::{self, Triple};
use wasmparser;
use cranelift_codegen::isa;
// use cranelift_codegen::print_errors::pretty_verifier_error;
// use cranelift_codegen::verifier;

pub use self::module::Module;
pub use self::instance::Instance;
pub use self::errors::{Error, ErrorKind};
pub use self::memory::LinearMemory;

pub struct ResultObject {
    /// A webassembly::Module object representing the compiled WebAssembly module.
    /// This Module can be instantiated again
    pub module: Module,
    /// A webassembly::Instance object that contains all the Exported WebAssembly
    /// functions.
    pub instance: Instance,
}

pub struct ImportObject {
}

/// The webassembly::instantiate() function allows you to compile and
/// instantiate WebAssembly code

/// Params: 
/// * `buffer_source`: A `Vec<u8>` containing the
///   binary code of the .wasm module you want to compile.

/// * `import_object`: An object containing the values to be imported
///   into the newly-created Instance, such as functions or
///   webassembly::Memory objects. There must be one matching property
///   for each declared import of the compiled module or else a
///   webassembly::LinkError is thrown.

/// Errors:
/// If the operation fails, the Result rejects with a 
/// webassembly::CompileError, webassembly::LinkError, or
/// webassembly::RuntimeError, depending on the cause of the failure.
pub fn instantiate(buffer_source: Vec<u8>, import_object: Option<ImportObject>) -> Result<ResultObject, ErrorKind> {
    let module = compile(buffer_source)?;
    let instance = Instance::new(&module, ptr::null(), &vec![]);
    Ok(ResultObject{
        module,
        instance
    })
}

/// The webassembly::compile() function compiles a webassembly::Module
/// from WebAssembly binary code.  This function is useful if it
/// is necessary to a compile a module before it can be instantiated
/// (otherwise, the webassembly::instantiate() function should be used).

/// Params: 
/// * `buffer_source`: A `Vec<u8>` containing the
///   binary code of the .wasm module you want to compile.

/// Errors:
/// If the operation fails, the Result rejects with a 
/// webassembly::CompileError.
pub fn compile(buffer_source: Vec<u8>) -> Result<Module, ErrorKind> {
    // TODO: This should be automatically validated when creating the Module
    if !validate(&buffer_source) {
        return Err(ErrorKind::CompileError("Module not valid".to_string()));
    }
    
    let module = Module::from_bytes(buffer_source, triple!("riscv64"), None)?;

    // let isa = isa::lookup(module.info.triple)
    //     .unwrap()
    //     .finish(module.info.flags);

    // for func in module.info.function_bodies.values() {
    //     verifier::verify_function(func, &*isa)
    //         .map_err(|errors| panic!(pretty_verifier_error(func, Some(&*isa), None, errors)))
    //         .unwrap();
    // };
    
    Ok(module)
}

/// The webassembly::validate() function validates a given typed
/// array of WebAssembly binary code, returning whether the bytes
/// form a valid wasm module (true) or not (false).

/// Params: 
/// * `buffer_source`: A `Vec<u8>` containing the
///   binary code of the .wasm module you want to compile.
pub fn validate(buffer_source: &Vec<u8>) -> bool {
    wasmparser::validate(buffer_source, None)
}