Initial reorg.

This is largely the same as #305, but updated for the current tree.

crates/api/src/trampoline/mod.rs

@@ -0,0 +1,52 @@
+//! Utility module to create trampolines in/out WebAssembly module.
+
+mod create_handle;
+mod func;
+mod global;
+mod memory;
+mod table;
+
+use crate::r#ref::HostRef;
+use alloc::rc::Rc;
+use anyhow::Result;
+
+use self::func::create_handle_with_function;
+use self::global::create_global;
+use self::memory::create_handle_with_memory;
+use self::table::create_handle_with_table;
+use super::{Callable, FuncType, GlobalType, MemoryType, Store, TableType, Val};
+
+pub use self::global::GlobalState;
+
+pub fn generate_func_export(
+    ft: &FuncType,
+    func: &Rc<dyn Callable + 'static>,
+    store: &HostRef<Store>,
+) -> Result<(wasmtime_runtime::InstanceHandle, wasmtime_runtime::Export)> {
+    let mut instance = create_handle_with_function(ft, func, store)?;
+    let export = instance.lookup("trampoline").expect("trampoline export");
+    Ok((instance, export))
+}
+
+pub fn generate_global_export(
+    gt: &GlobalType,
+    val: Val,
+) -> Result<(wasmtime_runtime::Export, GlobalState)> {
+    create_global(gt, val)
+}
+
+pub fn generate_memory_export(
+    m: &MemoryType,
+) -> Result<(wasmtime_runtime::InstanceHandle, wasmtime_runtime::Export)> {
+    let mut instance = create_handle_with_memory(m)?;
+    let export = instance.lookup("memory").expect("memory export");
+    Ok((instance, export))
+}
+
+pub fn generate_table_export(
+    t: &TableType,
+) -> Result<(wasmtime_runtime::InstanceHandle, wasmtime_runtime::Export)> {
+    let mut instance = create_handle_with_table(t)?;
+    let export = instance.lookup("table").expect("table export");
+    Ok((instance, export))
+}