denoland-deno/ext/ffi/00_ffi.js

// Copyright 2018-2021 the Deno authors. All rights reserved. MIT license.
"use strict";

((window) => {
  const core = window.Deno.core;
  const __bootstrap = window.__bootstrap;

  class DynamicLibrary {
    #rid;
    symbols = {};

    constructor(path, symbols) {
      this.#rid = core.opSync("op_ffi_load", { path, symbols });

      for (const symbol in symbols) {
        this.symbols[symbol] = symbols[symbol].nonblocking
          ? (...parameters) =>
            core.opAsync("op_ffi_call_nonblocking", {
              rid: this.#rid,
              symbol,
              parameters,
            })
          : (...parameters) =>
            core.opSync("op_ffi_call", { rid: this.#rid, symbol, parameters });
      }
    }

    close() {
      core.close(this.#rid);
    }
  }

  function dlopen(path, symbols) {
    // URL support is progressively enhanced by util in `runtime/js`.
    const pathFromURL = __bootstrap.util.pathFromURL ?? ((p) => p);
    return new DynamicLibrary(pathFromURL(path), symbols);
  }

  window.__bootstrap.ffi = { dlopen };
})(this);