| // Copyright 2018 The Go Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style |
| // license that can be found in the LICENSE file. |
| |
| (() => { |
| 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)"); |
| } |
| |
| // Map web browser API and Node.js API to a single common API (preferring web standards over Node.js API). |
| const isNodeJS = global.process && global.process.title === "node"; |
| if (isNodeJS) { |
| global.require = require; |
| global.fs = require("fs"); |
| |
| const nodeCrypto = require("crypto"); |
| global.crypto = { |
| getRandomValues(b) { |
| nodeCrypto.randomFillSync(b); |
| }, |
| }; |
| |
| global.performance = { |
| now() { |
| const [sec, nsec] = process.hrtime(); |
| return sec * 1000 + nsec / 1000000; |
| }, |
| }; |
| |
| const util = require("util"); |
| global.TextEncoder = util.TextEncoder; |
| global.TextDecoder = util.TextDecoder; |
| } else { |
| let outputBuf = ""; |
| global.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); |
| } |
| return buf.length; |
| }, |
| write(fd, buf, offset, length, position, callback) { |
| if (offset !== 0 || length !== buf.length || position !== null) { |
| throw new Error("not implemented"); |
| } |
| const n = this.writeSync(fd, buf); |
| callback(null, n); |
| }, |
| open(path, flags, mode, callback) { |
| const err = new Error("not implemented"); |
| err.code = "ENOSYS"; |
| callback(err); |
| }, |
| read(fd, buffer, offset, length, position, callback) { |
| const err = new Error("not implemented"); |
| err.code = "ENOSYS"; |
| callback(err); |
| }, |
| fsync(fd, callback) { |
| callback(null); |
| }, |
| }; |
| } |
| |
| const encoder = new TextEncoder("utf-8"); |
| const decoder = new TextDecoder("utf-8"); |
| |
| global.Go = class { |
| constructor() { |
| this.argv = ["js"]; |
| this.env = {}; |
| this.exit = (code) => { |
| if (code !== 0) { |
| console.warn("exit code:", code); |
| } |
| }; |
| this._exitPromise = new Promise((resolve) => { |
| this._resolveExitPromise = resolve; |
| }); |
| this._pendingCallback = null; |
| this._callbackTimeouts = new Map(); |
| this._nextCallbackTimeoutID = 1; |
| |
| const mem = () => { |
| // The buffer may change when requesting more memory. |
| return new DataView(this._inst.exports.mem.buffer); |
| } |
| |
| const setInt64 = (addr, v) => { |
| mem().setUint32(addr + 0, v, true); |
| mem().setUint32(addr + 4, Math.floor(v / 4294967296), true); |
| } |
| |
| const getInt64 = (addr) => { |
| const low = mem().getUint32(addr + 0, true); |
| const high = mem().getInt32(addr + 4, true); |
| return low + high * 4294967296; |
| } |
| |
| const loadValue = (addr) => { |
| const f = mem().getFloat64(addr, true); |
| if (f === 0) { |
| return undefined; |
| } |
| if (!isNaN(f)) { |
| return f; |
| } |
| |
| const id = mem().getUint32(addr, true); |
| return this._values[id]; |
| } |
| |
| const storeValue = (addr, v) => { |
| const nanHead = 0x7FF80000; |
| |
| if (typeof v === "number") { |
| if (isNaN(v)) { |
| mem().setUint32(addr + 4, nanHead, true); |
| mem().setUint32(addr, 0, true); |
| return; |
| } |
| if (v === 0) { |
| mem().setUint32(addr + 4, nanHead, true); |
| mem().setUint32(addr, 1, true); |
| return; |
| } |
| mem().setFloat64(addr, v, true); |
| return; |
| } |
| |
| switch (v) { |
| case undefined: |
| mem().setFloat64(addr, 0, true); |
| return; |
| case null: |
| mem().setUint32(addr + 4, nanHead, true); |
| mem().setUint32(addr, 2, true); |
| return; |
| case true: |
| mem().setUint32(addr + 4, nanHead, true); |
| mem().setUint32(addr, 3, true); |
| return; |
| case false: |
| mem().setUint32(addr + 4, nanHead, true); |
| mem().setUint32(addr, 4, true); |
| return; |
| } |
| |
| let ref = this._refs.get(v); |
| if (ref === undefined) { |
| ref = this._values.length; |
| this._values.push(v); |
| this._refs.set(v, ref); |
| } |
| let typeFlag = 0; |
| switch (typeof v) { |
| case "string": |
| typeFlag = 1; |
| break; |
| case "symbol": |
| typeFlag = 2; |
| break; |
| case "function": |
| typeFlag = 3; |
| break; |
| } |
| mem().setUint32(addr + 4, nanHead | typeFlag, true); |
| mem().setUint32(addr, ref, true); |
| } |
| |
| const loadSlice = (addr) => { |
| const array = getInt64(addr + 0); |
| const len = getInt64(addr + 8); |
| return new Uint8Array(this._inst.exports.mem.buffer, array, len); |
| } |
| |
| const loadSliceOfValues = (addr) => { |
| const array = getInt64(addr + 0); |
| const len = getInt64(addr + 8); |
| const a = new Array(len); |
| for (let i = 0; i < len; i++) { |
| a[i] = loadValue(array + i * 8); |
| } |
| return a; |
| } |
| |
| const loadString = (addr) => { |
| const saddr = getInt64(addr + 0); |
| const len = getInt64(addr + 8); |
| return decoder.decode(new DataView(this._inst.exports.mem.buffer, saddr, len)); |
| } |
| |
| const timeOrigin = Date.now() - performance.now(); |
| this.importObject = { |
| go: { |
| // Go's SP does not change as long as no Go code is running. Some operations (e.g. calls, getters and setters) |
| // may trigger a synchronous callback to Go. 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). |
| // This changes the SP, thus we have to update the SP used by the imported function. |
| |
| // func wasmExit(code int32) |
| "runtime.wasmExit": (sp) => { |
| const code = mem().getInt32(sp + 8, true); |
| this.exited = true; |
| delete this._inst; |
| delete this._values; |
| delete this._refs; |
| this.exit(code); |
| }, |
| |
| // func wasmWrite(fd uintptr, p unsafe.Pointer, n int32) |
| "runtime.wasmWrite": (sp) => { |
| const fd = getInt64(sp + 8); |
| const p = getInt64(sp + 16); |
| const n = mem().getInt32(sp + 24, true); |
| fs.writeSync(fd, new Uint8Array(this._inst.exports.mem.buffer, p, n)); |
| }, |
| |
| // func nanotime() int64 |
| "runtime.nanotime": (sp) => { |
| setInt64(sp + 8, (timeOrigin + performance.now()) * 1000000); |
| }, |
| |
| // func walltime() (sec int64, nsec int32) |
| "runtime.walltime": (sp) => { |
| const msec = (new Date).getTime(); |
| setInt64(sp + 8, msec / 1000); |
| mem().setInt32(sp + 16, (msec % 1000) * 1000000, true); |
| }, |
| |
| // func scheduleCallback(delay int64) int32 |
| "runtime.scheduleCallback": (sp) => { |
| const id = this._nextCallbackTimeoutID; |
| this._nextCallbackTimeoutID++; |
| this._callbackTimeouts.set(id, setTimeout( |
| () => { this._resume(); }, |
| getInt64(sp + 8) + 1, // setTimeout has been seen to fire up to 1 millisecond early |
| )); |
| mem().setInt32(sp + 16, id, true); |
| }, |
| |
| // func clearScheduledCallback(id int32) |
| "runtime.clearScheduledCallback": (sp) => { |
| const id = mem().getInt32(sp + 8, true); |
| clearTimeout(this._callbackTimeouts.get(id)); |
| this._callbackTimeouts.delete(id); |
| }, |
| |
| // func getRandomData(r []byte) |
| "runtime.getRandomData": (sp) => { |
| crypto.getRandomValues(loadSlice(sp + 8)); |
| }, |
| |
| // func stringVal(value string) ref |
| "syscall/js.stringVal": (sp) => { |
| storeValue(sp + 24, loadString(sp + 8)); |
| }, |
| |
| // func valueGet(v ref, p string) ref |
| "syscall/js.valueGet": (sp) => { |
| const result = Reflect.get(loadValue(sp + 8), loadString(sp + 16)); |
| sp = this._inst.exports.getsp(); // see comment above |
| storeValue(sp + 32, result); |
| }, |
| |
| // func valueSet(v ref, p string, x ref) |
| "syscall/js.valueSet": (sp) => { |
| Reflect.set(loadValue(sp + 8), loadString(sp + 16), loadValue(sp + 32)); |
| }, |
| |
| // func valueIndex(v ref, i int) ref |
| "syscall/js.valueIndex": (sp) => { |
| storeValue(sp + 24, Reflect.get(loadValue(sp + 8), getInt64(sp + 16))); |
| }, |
| |
| // valueSetIndex(v ref, i int, x ref) |
| "syscall/js.valueSetIndex": (sp) => { |
| Reflect.set(loadValue(sp + 8), getInt64(sp + 16), loadValue(sp + 24)); |
| }, |
| |
| // func valueCall(v ref, m string, args []ref) (ref, bool) |
| "syscall/js.valueCall": (sp) => { |
| try { |
| const v = loadValue(sp + 8); |
| const m = Reflect.get(v, loadString(sp + 16)); |
| const args = loadSliceOfValues(sp + 32); |
| const result = Reflect.apply(m, v, args); |
| sp = this._inst.exports.getsp(); // see comment above |
| storeValue(sp + 56, result); |
| mem().setUint8(sp + 64, 1); |
| } catch (err) { |
| storeValue(sp + 56, err); |
| mem().setUint8(sp + 64, 0); |
| } |
| }, |
| |
| // func valueInvoke(v ref, args []ref) (ref, bool) |
| "syscall/js.valueInvoke": (sp) => { |
| try { |
| const v = loadValue(sp + 8); |
| const args = loadSliceOfValues(sp + 16); |
| const result = Reflect.apply(v, undefined, args); |
| sp = this._inst.exports.getsp(); // see comment above |
| storeValue(sp + 40, result); |
| mem().setUint8(sp + 48, 1); |
| } catch (err) { |
| storeValue(sp + 40, err); |
| mem().setUint8(sp + 48, 0); |
| } |
| }, |
| |
| // func valueNew(v ref, args []ref) (ref, bool) |
| "syscall/js.valueNew": (sp) => { |
| try { |
| const v = loadValue(sp + 8); |
| const args = loadSliceOfValues(sp + 16); |
| const result = Reflect.construct(v, args); |
| sp = this._inst.exports.getsp(); // see comment above |
| storeValue(sp + 40, result); |
| mem().setUint8(sp + 48, 1); |
| } catch (err) { |
| storeValue(sp + 40, err); |
| mem().setUint8(sp + 48, 0); |
| } |
| }, |
| |
| // func valueLength(v ref) int |
| "syscall/js.valueLength": (sp) => { |
| setInt64(sp + 16, parseInt(loadValue(sp + 8).length)); |
| }, |
| |
| // valuePrepareString(v ref) (ref, int) |
| "syscall/js.valuePrepareString": (sp) => { |
| const str = encoder.encode(String(loadValue(sp + 8))); |
| storeValue(sp + 16, str); |
| setInt64(sp + 24, str.length); |
| }, |
| |
| // valueLoadString(v ref, b []byte) |
| "syscall/js.valueLoadString": (sp) => { |
| const str = loadValue(sp + 8); |
| loadSlice(sp + 16).set(str); |
| }, |
| |
| // func valueInstanceOf(v ref, t ref) bool |
| "syscall/js.valueInstanceOf": (sp) => { |
| mem().setUint8(sp + 24, loadValue(sp + 8) instanceof loadValue(sp + 16)); |
| }, |
| |
| "debug": (value) => { |
| console.log(value); |
| }, |
| } |
| }; |
| } |
| |
| async run(instance) { |
| this._inst = instance; |
| this._values = [ // TODO: garbage collection |
| NaN, |
| 0, |
| null, |
| true, |
| false, |
| global, |
| this._inst.exports.mem, |
| this, |
| ]; |
| this._refs = new Map(); |
| this.exited = false; |
| |
| const mem = new DataView(this._inst.exports.mem.buffer) |
| |
| // Pass command line arguments and environment variables to WebAssembly by writing them to the linear memory. |
| let offset = 4096; |
| |
| const strPtr = (str) => { |
| let ptr = offset; |
| new Uint8Array(mem.buffer, offset, str.length + 1).set(encoder.encode(str + "\0")); |
| offset += str.length + (8 - (str.length % 8)); |
| return ptr; |
| }; |
| |
| const argc = this.argv.length; |
| |
| const argvPtrs = []; |
| this.argv.forEach((arg) => { |
| argvPtrs.push(strPtr(arg)); |
| }); |
| |
| const keys = Object.keys(this.env).sort(); |
| argvPtrs.push(keys.length); |
| keys.forEach((key) => { |
| argvPtrs.push(strPtr(`${key}=${this.env[key]}`)); |
| }); |
| |
| const argv = offset; |
| argvPtrs.forEach((ptr) => { |
| mem.setUint32(offset, ptr, true); |
| mem.setUint32(offset + 4, 0, true); |
| offset += 8; |
| }); |
| |
| this._inst.exports.run(argc, argv); |
| if (this.exited) { |
| this._resolveExitPromise(); |
| } |
| await this._exitPromise; |
| } |
| |
| _resume() { |
| if (this.exited) { |
| throw new Error("bad callback: Go program has already exited"); |
| } |
| this._inst.exports.resume(); |
| if (this.exited) { |
| this._resolveExitPromise(); |
| } |
| } |
| |
| _makeCallbackHelper(id) { |
| const go = this; |
| return function () { |
| const cb = { id: id, this: this, args: arguments }; |
| go._pendingCallback = cb; |
| go._resume(); |
| return cb.result; |
| }; |
| } |
| } |
| |
| if (isNodeJS) { |
| if (process.argv.length < 3) { |
| process.stderr.write("usage: go_js_wasm_exec [wasm binary] [arguments]\n"); |
| 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 callback is pending |
| if (code === 0 && !go.exited) { |
| // deadlock, make Go print error and stack traces |
| go._pendingCallback = { id: 0 }; |
| go._resume(); |
| } |
| }); |
| return go.run(result.instance); |
| }).catch((err) => { |
| throw err; |
| }); |
| } |
| })(); |