libSystem.Native.Browser.Utils.footer.js

//! Licensed to the .NET Foundation under one or more agreements.
//! The .NET Foundation licenses this file to you under the MIT license.

/**
 * This is root of **Emscripten library** that would become part of `dotnet.native.js`
 * It implements utilities and a public JS API related to memory and runtime hosting.
 */

/* eslint-disable no-undef */
function libBrowserUtilsFactory() {
    // this executes the function at link time in order to capture exports
    // this is what Emscripten does for linking JS libraries
    // https://emscripten.org/docs/porting/connecting_cpp_and_javascript/Interacting-with-code.html#javascript-limits-in-library-files
    // it would execute the code at link time and call .toString() on functions to move it to the final output
    // this process would loose any closure references, unless they are passed to `__deps` and also explicitly given to the linker
    // JS name mangling and minification also applies, see src\native\rollup.config.defines.js and `reserved` there
    const exports = {};
    libBrowserUtils(exports);

    let commonDeps = [
        "$libBrowserUtilsFn",
        "$DOTNET",
        "GetDotNetRuntimeContractDescriptor",
        "_exit",
        "abort",
        "__trap",
        "__stack_pointer",
        "__coreclr_wasm_rtlrestorecontext_tag",
        "__async_continuation",
        "$readI53FromU64",
        "$readI53FromI64",
        "$writeI53ToI64"
    ];
    const mergeBrowserUtils = {
        $BROWSER_UTILS: {
            selfInitialize: () => {
                if (typeof dotnetInternals !== "undefined") {
                    BROWSER_UTILS.dotnetInternals = dotnetInternals;

                    const exports = {};
                    libBrowserUtilsFn(exports);
                    exports.dotnetInitializeModule(dotnetInternals);
                }
            },
        },
        $libBrowserUtilsFn: libBrowserUtils,
        $BROWSER_UTILS__postset: "BROWSER_UTILS.selfInitialize()",
        $BROWSER_UTILS__deps: commonDeps,
    };

    // install cross-module symbols as "_ems_" ambient symbols in Emscripten closure
    // keep in sync with `reserved`+`keep_fnames` in src\native\rollup.config.defines.js
    for (const exportName of Reflect.ownKeys(exports._ems_ambient_)) {
        const name = String(exportName);
        if (name === "dotnetInternals") continue;
        if (name === "Module") continue;
        const emName = "$" + name;
        mergeBrowserUtils[emName] = exports._ems_ambient_[exportName];
        commonDeps.push(emName);
    }

    autoAddDeps(mergeBrowserUtils, "$BROWSER_UTILS");
    addToLibrary(mergeBrowserUtils);
}

libBrowserUtilsFactory();