From 2bca3a02ac3c06e4dac74c10c4b6c650ae53d148 Mon Sep 17 00:00:00 2001 From: John Bartholomew Date: Wed, 17 Apr 2024 15:20:05 +0100 Subject: [PATCH] update js/wasm_exec.js - the Go WASM JS glue --- doc/js/wasm_exec.js | 138 +++++++++++--------------------------------- 1 file changed, 35 insertions(+), 103 deletions(-) diff --git a/doc/js/wasm_exec.js b/doc/js/wasm_exec.js index 231185a12..bc6f21024 100644 --- a/doc/js/wasm_exec.js +++ b/doc/js/wasm_exec.js @@ -2,54 +2,25 @@ // Use of this source code is governed by a BSD-style // license that can be found in the LICENSE file. -(() => { - // Map multiple JavaScript environments to a single common API, - // preferring web standards over Node.js API. - // - // Environments considered: - // - Browsers - // - Node.js - // - Electron - // - Parcel - // - Webpack - - if (typeof global !== "undefined") { - // global already exists - } else if (typeof window !== "undefined") { - window.global = window; - } else if (typeof self !== "undefined") { - self.global = self; - } else { - throw new Error("cannot export Go (neither global, window nor self is defined)"); - } - - if (!global.require && typeof require !== "undefined") { - global.require = require; - } - - if (!global.fs && global.require) { - const fs = require("fs"); - if (typeof fs === "object" && fs !== null && Object.keys(fs).length !== 0) { - global.fs = fs; - } - } +"use strict"; +(() => { const enosys = () => { const err = new Error("not implemented"); err.code = "ENOSYS"; return err; }; - if (!global.fs) { + if (!globalThis.fs) { let outputBuf = ""; - global.fs = { + globalThis.fs = { constants: { O_WRONLY: -1, O_RDWR: -1, O_CREAT: -1, O_TRUNC: -1, O_APPEND: -1, O_EXCL: -1 }, // unused writeSync(fd, buf) { outputBuf += decoder.decode(buf); const nl = outputBuf.lastIndexOf("\n"); if (nl != -1) { - console.log(outputBuf.substr(0, nl)); - outputBuf = outputBuf.substr(nl + 1); + console.log(outputBuf.substring(0, nl)); + outputBuf = outputBuf.substring(nl + 1); } return buf.length; }, @@ -87,8 +58,8 @@ }; } - if (!global.process) { - global.process = { + if (!globalThis.process) { + globalThis.process = { getuid() { return -1; }, getgid() { return -1; }, geteuid() { return -1; }, @@ -102,47 +73,26 @@ } } - if (!global.crypto && global.require) { - const nodeCrypto = require("crypto"); - global.crypto = { - getRandomValues(b) { - nodeCrypto.randomFillSync(b); - }, - }; - } - if (!global.crypto) { - throw new Error("global.crypto is not available, polyfill required (getRandomValues only)"); + if (!globalThis.crypto) { + throw new Error("globalThis.crypto is not available, polyfill required (crypto.getRandomValues only)"); } - if (!global.performance) { - global.performance = { - now() { - const [sec, nsec] = process.hrtime(); - return sec * 1000 + nsec / 1000000; - }, - }; + if (!globalThis.performance) { + throw new Error("globalThis.performance is not available, polyfill required (performance.now only)"); } - if (!global.TextEncoder && global.require) { - global.TextEncoder = require("util").TextEncoder; - } - if (!global.TextEncoder) { - throw new Error("global.TextEncoder is not available, polyfill required"); + if (!globalThis.TextEncoder) { + throw new Error("globalThis.TextEncoder is not available, polyfill required"); } - if (!global.TextDecoder && global.require) { - global.TextDecoder = require("util").TextDecoder; + if (!globalThis.TextDecoder) { + throw new Error("globalThis.TextDecoder is not available, polyfill required"); } - if (!global.TextDecoder) { - throw new Error("global.TextDecoder is not available, polyfill required"); - } - - // End of polyfills for common API. const encoder = new TextEncoder("utf-8"); const decoder = new TextDecoder("utf-8"); - global.Go = class { + globalThis.Go = class { constructor() { this.argv = ["js"]; this.env = {}; @@ -163,6 +113,10 @@ this.mem.setUint32(addr + 4, Math.floor(v / 4294967296), true); } + const setInt32 = (addr, v) => { + this.mem.setUint32(addr + 0, v, true); + } + const getInt64 = (addr) => { const low = this.mem.getUint32(addr + 0, true); const high = this.mem.getInt32(addr + 4, true); @@ -256,7 +210,10 @@ const timeOrigin = Date.now() - performance.now(); this.importObject = { - go: { + _gotest: { + add: (a, b) => a + b, + }, + gojs: { // Go's SP does not change as long as no Go code is running. Some operations (e.g. calls, getters and setters) // may synchronously trigger a Go event handler. This makes Go code get executed in the middle of the imported // function. A goroutine can switch to a new stack if the current stack is too small (see morestack function). @@ -319,7 +276,7 @@ this._resume(); } }, - getInt64(sp + 8) + 1, // setTimeout has been seen to fire up to 1 millisecond early + getInt64(sp + 8), )); this.mem.setInt32(sp + 16, id, true); }, @@ -517,7 +474,7 @@ null, true, false, - global, + globalThis, this, ]; this._goRefCounts = new Array(this._values.length).fill(Infinity); // number of references that Go has to a JS value, indexed by reference id @@ -526,7 +483,7 @@ [null, 2], [true, 3], [false, 4], - [global, 5], + [globalThis, 5], [this, 6], ]); this._idPool = []; // unused ids that have been garbage collected @@ -567,6 +524,13 @@ offset += 8; }); + // The linker guarantees global data starts from at least wasmMinDataAddr. + // Keep in sync with cmd/link/internal/ld/data.go:wasmMinDataAddr. + const wasmMinDataAddr = 4096 + 8192; + if (offset >= wasmMinDataAddr) { + throw new Error("total length of command line and environment variables exceeds limit"); + } + this._inst.exports.run(argc, argv); if (this.exited) { this._resolveExitPromise(); @@ -594,36 +558,4 @@ }; } } - - if ( - typeof module !== "undefined" && - global.require && - global.require.main === module && - global.process && - global.process.versions && - !global.process.versions.electron - ) { - if (process.argv.length < 3) { - console.error("usage: go_js_wasm_exec [wasm binary] [arguments]"); - process.exit(1); - } - - const go = new Go(); - go.argv = process.argv.slice(2); - go.env = Object.assign({ TMPDIR: require("os").tmpdir() }, process.env); - go.exit = process.exit; - WebAssembly.instantiate(fs.readFileSync(process.argv[2]), go.importObject).then((result) => { - process.on("exit", (code) => { // Node.js exits if no event handler is pending - if (code === 0 && !go.exited) { - // deadlock, make Go print error and stack traces - go._pendingEvent = { id: 0 }; - go._resume(); - } - }); - return go.run(result.instance); - }).catch((err) => { - console.error(err); - process.exit(1); - }); - } })();