Struct wasmedge_sdk::Vm

pub struct Vm { /* private fields */ }

A Vm defines a virtual environment for managing WebAssembly programs.

Example

The example below presents how to register a module as named module in a Vm instance and run a target wasm function.

// If the version of rust used is less than v1.63, please uncomment the follow attribute.
// #![feature(explicit_generic_args_with_impl_trait)]

use wasmedge_sdk::{params, VmBuilder, WasmVal};
use wasmedge_types::{wat2wasm, ValType};

#[cfg_attr(test, test)]
fn main() -> Result<(), Box<dyn std::error::Error>> {
    // create a Vm context
    let vm = VmBuilder::new().build()?;

    // register a wasm module from the given in-memory wasm bytes
    let wasm_bytes = wat2wasm(
        br#"(module
        (export "fib" (func $fib))
        (func $fib (param $n i32) (result i32)
         (if
          (i32.lt_s
           (get_local $n)
           (i32.const 2)
          )
          (return
           (i32.const 1)
          )
         )
         (return
          (i32.add
           (call $fib
            (i32.sub
             (get_local $n)
             (i32.const 2)
            )
           )
           (call $fib
            (i32.sub
             (get_local $n)
             (i32.const 1)
            )
           )
          )
         )
        )
       )
    "#,
    )?;
    let mut vm = vm.register_module_from_bytes("extern", wasm_bytes)?;

    // run `fib` function in the named module instance
    let returns = vm.run_func(Some("extern"), "fib", params!(10))?;
    assert_eq!(returns.len(), 1);
    assert_eq!(returns[0].to_i32(), 89);

    Ok(())
}

Implementations

impl Vm

pub fn register_module(
    self,
    mod_name: Option<&str>,
    module: Module
) -> WasmEdgeResult<Self>

Registers a wasm module into this vm as a named or active module instance.

Arguments

• mod_name - The exported name for the registered module. If None, then the module is registered as an active instance.

• module - The module to be registered.

Error

If fail to register the given module, then an error is returned.

pub fn register_module_from_file(
    self,
    mod_name: impl AsRef<str>,
    file: impl AsRef<Path>
) -> WasmEdgeResult<Self>

Registers a wasm module into the vm from a wasm file.

Arguments

• mod_name - The exported name for the registered module.

• file - A wasm file or an AOT wasm file.

Error

If fail to register, then an error is returned.

pub fn register_module_from_bytes(
    self,
    mod_name: impl AsRef<str>,
    bytes: impl AsRef<[u8]>
) -> WasmEdgeResult<Self>

Registers a wasm module from the given in-memory wasm bytes into this vm.

Arguments

• mod_name - The exported name for the registered module.

• bytes - The in-memory wasm bytes.

Error

If fail to register, then an error is returned.

pub fn register_import_module(self, import: ImportObject) -> WasmEdgeResult<Self>

Registers an import object into this vm.

Arguments

• import - The import object to be registered.

Error

If fail to register, then an error is returned.

pub fn auto_detect_plugins(self) -> WasmEdgeResult<Self>

Auto detect all plugins in WASMEDGE_PLUGIN_PATH

Error

If fail to register plugin instance, then an error is returned.

pub fn run_func(
    &self,
    mod_name: Option<&str>,
    func_name: impl AsRef<str>,
    args: impl IntoIterator<Item = WasmValue>
) -> WasmEdgeResult<Vec<WasmValue>>

Runs an exported wasm function in a (named or active) module instance.

Arguments

• mod_name - The exported name of the module instance, which holds the target function. If None, then the active module is used.

• func_name - The exported name of the target wasm function.

• args - The arguments to be passed to the target wasm function.

Error

If fail to run the wasm function, then an error is returned.

pub async fn run_func_async(
    &self,
    mod_name: Option<&str>,
    func_name: impl AsRef<str> + Send,
    args: impl IntoIterator<Item = WasmValue> + Send
) -> WasmEdgeResult<Vec<WasmValue>>

Asynchronously runs an exported wasm function in a (named or active) module instance.

Arguments

• mod_name - The exported name of the module instance, which holds the target function. If None, then the active module is used.

• func_name - The exported name of the target wasm function.

• args - The arguments to be passed to the target wasm function.

Error

If fail to run the wasm function, then an error is returned.

pub fn run_func_from_module(
    &mut self,
    module: Module,
    func_name: impl AsRef<str>,
    args: impl IntoIterator<Item = WasmValue>
) -> WasmEdgeResult<Vec<WasmValue>>

Runs an exported wasm function from the given wasm module.

This method is a shortcut of calling register_module and run_func in sequence.

Arguments

• module - A wasm module.

• func_name - The exported name of the target wasm function.

• args - The arguments to be passed to the target wasm function.

Error

If fail to run, then an error is returned.

pub async fn run_func_from_module_async<N, A>(
    &mut self,
    module: Module,
    func_name: N,
    args: A
) -> WasmEdgeResult<Vec<WasmValue>>where
    N: AsRef<str> + Send,
    A: IntoIterator<Item = WasmValue> + Send,

Runs an exported wasm function from the given wasm module.

To use this method, turn on the async feature.

Arguments

• module - A wasm module.

• func_name - The exported name of the target wasm function.

• args - The arguments to be passed to the target wasm function.

Error

If fail to run, then an error is returned.

pub fn run_func_from_file(
    &mut self,
    file: impl AsRef<Path>,
    func_name: impl AsRef<str>,
    args: impl IntoIterator<Item = WasmValue>
) -> WasmEdgeResult<Vec<WasmValue>>

Runs an exported wasm function from the given wasm file.

Arguments

• file - A wasm file or an AOT wasm file.

• func_name - The exported name of the target wasm function.

• args - The arguments to be passed to the target wasm function.

Error

If fail to run, then an error is returned.

pub async fn run_func_from_file_async<P, N, A>(
    &mut self,
    file: P,
    func_name: N,
    args: A
) -> WasmEdgeResult<Vec<WasmValue>>where
    P: AsRef<Path>,
    N: AsRef<str> + Send,
    A: IntoIterator<Item = WasmValue> + Send,

Asynchronously runs an exported wasm function from the given wasm file.

Arguments

• file - A wasm file or an AOT wasm file.

• func_name - The exported name of the target wasm function.

• args - The arguments to be passed to the target wasm function.

Error

If fail to run, then an error is returned.

pub fn run_func_from_bytes(
    &mut self,
    bytes: &[u8],
    func_name: impl AsRef<str>,
    args: impl IntoIterator<Item = WasmValue>
) -> WasmEdgeResult<Vec<WasmValue>>

Runs an exported wasm function from the given in-memory wasm bytes.

Arguments

• bytes - The in-memory wasm bytes.

• func_name - The exported name of the target wasm function.

• args - The arguments to be passed to the target wasm function.

Error

If fail to run, then an error is returned.

pub async fn run_func_from_bytes_async<N, A>(
    &mut self,
    bytes: &[u8],
    func_name: N,
    args: A
) -> WasmEdgeResult<Vec<WasmValue>>where
    N: AsRef<str> + Send,
    A: IntoIterator<Item = WasmValue> + Send,

Runs an exported wasm function from the given in-memory wasm bytes.

Arguments

• bytes - The in-memory wasm bytes.

• func_name - The exported name of the target wasm function.

• args - The arguments to be passed to the target wasm function.

Error

If fail to run, then an error is returned.

pub fn statistics(&self) -> Option<&Statistics>

Returns a reference to the internal statistics from this vm.

pub fn statistics_mut(&mut self) -> Option<&mut Statistics>

Returns a mutable reference to the internal statistics from this vm.

pub fn executor(&self) -> &Executor

Returns a reference to the internal executor from this vm.

pub fn executor_mut(&mut self) -> &mut Executor

Returns a mutable reference to the internal executor from this vm.

pub fn store(&self) -> &Store

Returns a reference to the internal store from this vm.

pub fn store_mut(&mut self) -> &mut Store

Returns a mutable reference to the internal store from this vm.

pub fn wasi_module(&self) -> Option<&WasiInstance>

Returns a reference to the wasi module instance from this vm.

To retrieve the [wasi module instance], a config with the enabled wasi option should be given when create this vm.

pub fn wasi_module_mut(&mut self) -> Option<&mut WasiInstance>

Returns a mutable reference to the wasi module instance from this vm.

To retrieve the [wasi module instance], a config with the enabled wasi option should be given when create this vm.

pub fn named_module(&self, name: impl AsRef<str>) -> WasmEdgeResult<&Instance>

Returns a reference to the named module instance with the given name from this vm.

Argument

• name - The exported name of the target module instance.

Error

If fail to get the reference to the target module instance, then an error is returned.

pub fn named_module_mut(
    &mut self,
    name: impl AsRef<str>
) -> WasmEdgeResult<&mut Instance>

Returns a mutable reference to the named module instance with the given name.

Argument

• name - The exported name of the target module instance.

Error

If fail to get the mutable reference to the target module instance, then an error is returned.

pub fn active_module(&self) -> WasmEdgeResult<&Instance>

Returns a reference to the active module instance from this vm.

Error

If fail to get the reference to the active module instance, then an error is returned.

pub fn active_module_mut(&mut self) -> WasmEdgeResult<&mut Instance>

Returns a mutable reference to the active module instance from this vm.

Error

If fail to get the mutable reference to the active module instance, then an error is returned.

pub fn contains_module(&self, mod_name: impl AsRef<str>) -> bool

Checks if the vm contains a named module instance.

Argument

• mod_name - The exported name of the target module instance.

pub fn named_instance_count(&self) -> u32

Returns the count of the named module instances this vm holds.

pub fn instance_names(&self) -> Vec<String>

Returns the names of all named module instances this vm holds.

Trait Implementations

impl Clone for Vm

fn clone(&self) -> Vm

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Vm

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.