wain-exec 0.3.1

WebAssembly syntax tree executor for wain project
Documentation 
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#![forbid(unsafe_code)]
#![warn(clippy::dbg_macro)]

extern crate wain_ast;

pub mod trap;

mod cast;
mod globals;
mod import;
mod memory;
mod runtime;
mod stack;
mod table;
mod value;

pub use import::{check_func_signature, DefaultImporter, ImportInvalidError, ImportInvokeError, Importer};
pub use memory::Memory;
pub use runtime::Runtime;
pub use stack::Stack;
pub use value::Value;

use std::io;
use trap::Result;
use wain_ast::Module;

/// A convenient function to execute a WebAssembly module.
///
/// This function takes parsed and validated WebAssembly module and it invokes a start function if
/// presents. Otherwise it invokes a function exported as '_start' with no argument.
///
/// For standard I/O speed, this function locks io::Stdin and io::Stdout objects because currently
/// getchar() and putchar() don't buffer its input/output. This behavior may change in the future.
///
/// If the behavior is not acceptable, please make an abstract machine runtime with
/// Runtime::instantiate.
///
/// You will need importer for initializing Runtime struct. Please use DefaultImporter::with_stdio()
/// or make your own importer struct which implements Importer trait.
pub fn execute(module: &Module<'_>) -> Result<()> {
    let stdin = io::stdin();
    let stdout = io::stdout();
    let importer = DefaultImporter::with_stdio(stdin.lock(), stdout.lock());
    let mut runtime = Runtime::instantiate(module, importer)?;
    if runtime.module().entrypoint.is_none() {
        runtime.invoke("_start", &[])?;
    }
    Ok(())
}