zheng d4d8c5534b webpack 23 hours ago
..
esm d4d8c5534b webpack 23 hours ago
lib d4d8c5534b webpack 23 hours ago
LICENSE d4d8c5534b webpack 23 hours ago
README.md d4d8c5534b webpack 23 hours ago
package.json d4d8c5534b webpack 23 hours ago

README.md

@webassemblyjs/wasm-edit

Rewrite a WASM binary

Replace in-place an AST node in the binary.

Installation

yarn add @webassemblyjs/wasm-edit

Usage

Update:

import { edit } from "@webassemblyjs/wasm-edit";

const binary = [/*...*/];

const visitors = {
  ModuleImport({ node }) {
    node.module = "foo";
    node.name = "bar";
  }
};

const newBinary = edit(binary, visitors);

Replace:

import { edit } from "@webassemblyjs/wasm-edit";

const binary = [/*...*/];

const visitors = {
  Instr(path) {
    const newNode = t.callInstruction(t.indexLiteral(0));
    path.replaceWith(newNode);
  }
};

const newBinary = edit(binary, visitors);

Remove:

import { edit } from "@webassemblyjs/wasm-edit";

const binary = [/*...*/];

const visitors = {
  ModuleExport({ node }) {
    path.remove()
  }
};

const newBinary = edit(binary, visitors);

Insert:

import { add } from "@webassemblyjs/wasm-edit";

const binary = [/*...*/];

const newBinary = add(actualBinary, [
  t.moduleImport("env", "mem", t.memory(t.limit(1)))
]);

Providing the AST

Providing an AST allows you to handle the decoding yourself, here is the API:

addWithAST(Program, ArrayBuffer, Array<Node>): ArrayBuffer;
editWithAST(Program, ArrayBuffer, visitors): ArrayBuffer;

Note that the AST will be updated in-place.