misc/wasm/wasm_exec.js - go - Git at Google

 // 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.

 (() => {
 	// Map web browser API and Node.js API to a single common API (preferring web standards over Node.js API).
 	const isNodeJS = typeof process !== "undefined";
 	if (isNodeJS) {
 		global.require = require;
 		global.fs = require("fs");

 		const nodeCrypto = require("crypto");
 		global.crypto = {
 			getRandomValues(b) {
 				nodeCrypto.randomFillSync(b);
 			},
 		};

 		const now = () => {
 			const [sec, nsec] = process.hrtime();
 			return sec * 1000 + nsec / 1000000;
 		};
 		global.performance = {
 			timeOrigin: Date.now() - now(),
 			now: now,
 		};

 		const util = require("util");
 		global.TextEncoder = util.TextEncoder;
 		global.TextDecoder = util.TextDecoder;
 	} else {
 		window.global = window;

 		let outputBuf = "";
 		global.fs = {
 			constants: {},
 			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;
 			},
 		};
 	}

 	const encoder = new TextEncoder("utf-8");
 	const decoder = new TextDecoder("utf-8");

 	global.Go = class {
 		constructor() {
 			this.argv = [];
 			this.env = {};
 			this.exit = (code) => {
 				if (code !== 0) {
 					console.warn("exit code:", code);
 				}
 			};

 			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 id = mem().getUint32(addr, true);
 				return this._values[id];
 			}

 			const storeValue = (addr, v) => {
 				if (v === undefined) {
 					mem().setUint32(addr, 0, true);
 					return;
 				}
 				if (v === null) {
 					mem().setUint32(addr, 1, true);
 					return;
 				}
 				this._values.push(v);
 				mem().setUint32(addr, this._values.length - 1, 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++) {
 					const id = mem().getUint32(array + i * 4, true);
 					a[i] = this._values[id];
 				}
 				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));
 			}

 			this.importObject = {
 				go: {
 					// func wasmExit(code int32)
 					"runtime.wasmExit": (sp) => {
 						this.exit(mem().getInt32(sp + 8, true));
 					},

 					// 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, (performance.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 boolVal(value bool) Value
 					"syscall/js.boolVal": (sp) => {
 						storeValue(sp + 16, mem().getUint8(sp + 8) !== 0);
 					},

 					// func intVal(value int) Value
 					"syscall/js.intVal": (sp) => {
 						storeValue(sp + 16, getInt64(sp + 8));
 					},

 					// func floatVal(value float64) Value
 					"syscall/js.floatVal": (sp) => {
 						storeValue(sp + 16, mem().getFloat64(sp + 8, true));
 					},

 					// func stringVal(value string) Value
 					"syscall/js.stringVal": (sp) => {
 						storeValue(sp + 24, loadString(sp + 8));
 					},

 					// func (v Value) Get(key string) Value
 					"syscall/js.Value.Get": (sp) => {
 						storeValue(sp + 32, Reflect.get(loadValue(sp + 8), loadString(sp + 16)));
 					},

 					// func (v Value) set(key string, value Value)
 					"syscall/js.Value.set": (sp) => {
 						Reflect.set(loadValue(sp + 8), loadString(sp + 16), loadValue(sp + 32));
 					},

 					// func (v Value) Index(i int) Value
 					"syscall/js.Value.Index": (sp) => {
 						storeValue(sp + 24, Reflect.get(loadValue(sp + 8), getInt64(sp + 16)));
 					},

 					// func (v Value) setIndex(i int, value Value)
 					"syscall/js.Value.setIndex": (sp) => {
 						Reflect.set(loadValue(sp + 8), getInt64(sp + 16), loadValue(sp + 24));
 					},

 					// func (v Value) call(name string, args []Value) (Value, bool)
 					"syscall/js.Value.call": (sp) => {
 						try {
 							const v = loadValue(sp + 8);
 							const m = Reflect.get(v, loadString(sp + 16));
 							const args = loadSliceOfValues(sp + 32);
 							storeValue(sp + 56, Reflect.apply(m, v, args));
 							mem().setUint8(sp + 60, 1);
 						} catch (err) {
 							storeValue(sp + 56, err);
 							mem().setUint8(sp + 60, 0);
 						}
 					},

 					// func (v Value) invoke(args []Value) (Value, bool)
 					"syscall/js.Value.invoke": (sp) => {
 						try {
 							const v = loadValue(sp + 8);
 							const args = loadSliceOfValues(sp + 16);
 							storeValue(sp + 40, Reflect.apply(v, undefined, args));
 							mem().setUint8(sp + 44, 1);
 						} catch (err) {
 							storeValue(sp + 40, err);
 							mem().setUint8(sp + 44, 0);
 						}
 					},

 					// func (v Value) new(args []Value) (Value, bool)
 					"syscall/js.Value.new": (sp) => {
 						try {
 							const v = loadValue(sp + 8);
 							const args = loadSliceOfValues(sp + 16);
 							storeValue(sp + 40, Reflect.construct(v, args));
 							mem().setUint8(sp + 44, 1);
 						} catch (err) {
 							storeValue(sp + 40, err);
 							mem().setUint8(sp + 44, 0);
 						}
 					},

 					// func (v Value) Float() float64
 					"syscall/js.Value.Float": (sp) => {
 						mem().setFloat64(sp + 16, parseFloat(loadValue(sp + 8)), true);
 					},

 					// func (v Value) Int() int
 					"syscall/js.Value.Int": (sp) => {
 						setInt64(sp + 16, parseInt(loadValue(sp + 8)));
 					},

 					// func (v Value) Bool() bool
 					"syscall/js.Value.Bool": (sp) => {
 						mem().setUint8(sp + 16, !!loadValue(sp + 8));
 					},

 					// func (v Value) Length() int
 					"syscall/js.Value.Length": (sp) => {
 						setInt64(sp + 16, parseInt(loadValue(sp + 8).length));
 					},

 					// func (v Value) prepareString() (Value, int)
 					"syscall/js.Value.prepareString": (sp) => {
 						const str = encoder.encode(String(loadValue(sp + 8)));
 						storeValue(sp + 16, str);
 						setInt64(sp + 24, str.length);
 					},

 					// func (v Value) loadString(b []byte)
 					"syscall/js.Value.loadString": (sp) => {
 						const str = loadValue(sp + 8);
 						loadSlice(sp + 16).set(str);
 					},

 					"debug": (value) => {
 						console.log(value);
 					},
 				}
 			};
 		}

 		async run(instance) {
 			this._inst = instance;
 			this._values = [undefined, null, global, this._inst.exports.mem]; // TODO: garbage collection

 			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 (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 = process.env;
 		go.exit = process.exit;
 		WebAssembly.instantiate(fs.readFileSync(process.argv[2]), go.importObject).then((result) => {
 			return go.run(result.instance);
 		}).catch((err) => {
 			console.error(err);
 			process.exit(1);
 		});
 	}
 })();
	// 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.

	(() => {
	// Map web browser API and Node.js API to a single common API (preferring web standards over Node.js API).
	const isNodeJS = typeof process !== "undefined";
	if (isNodeJS) {
	global.require = require;
	global.fs = require("fs");

	const nodeCrypto = require("crypto");
	global.crypto = {
	getRandomValues(b) {
	nodeCrypto.randomFillSync(b);
	},
	};

	const now = () => {
	const [sec, nsec] = process.hrtime();
	return sec * 1000 + nsec / 1000000;
	};
	global.performance = {
	timeOrigin: Date.now() - now(),
	now: now,
	};

	const util = require("util");
	global.TextEncoder = util.TextEncoder;
	global.TextDecoder = util.TextDecoder;
	} else {
	window.global = window;

	let outputBuf = "";
	global.fs = {
	constants: {},
	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;
	},
	};
	}

	const encoder = new TextEncoder("utf-8");
	const decoder = new TextDecoder("utf-8");

	global.Go = class {
	constructor() {
	this.argv = [];
	this.env = {};
	this.exit = (code) => {
	if (code !== 0) {
	console.warn("exit code:", code);
	}
	};

	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 id = mem().getUint32(addr, true);
	return this._values[id];
	}

	const storeValue = (addr, v) => {
	if (v === undefined) {
	mem().setUint32(addr, 0, true);
	return;
	}
	if (v === null) {
	mem().setUint32(addr, 1, true);
	return;
	}
	this._values.push(v);
	mem().setUint32(addr, this._values.length - 1, 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++) {
	const id = mem().getUint32(array + i * 4, true);
	a[i] = this._values[id];
	}
	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));
	}

	this.importObject = {
	go: {
	// func wasmExit(code int32)
	"runtime.wasmExit": (sp) => {
	this.exit(mem().getInt32(sp + 8, true));
	},

	// 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, (performance.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 boolVal(value bool) Value
	"syscall/js.boolVal": (sp) => {
	storeValue(sp + 16, mem().getUint8(sp + 8) !== 0);
	},

	// func intVal(value int) Value
	"syscall/js.intVal": (sp) => {
	storeValue(sp + 16, getInt64(sp + 8));
	},

	// func floatVal(value float64) Value
	"syscall/js.floatVal": (sp) => {
	storeValue(sp + 16, mem().getFloat64(sp + 8, true));
	},

	// func stringVal(value string) Value
	"syscall/js.stringVal": (sp) => {
	storeValue(sp + 24, loadString(sp + 8));
	},

	// func (v Value) Get(key string) Value
	"syscall/js.Value.Get": (sp) => {
	storeValue(sp + 32, Reflect.get(loadValue(sp + 8), loadString(sp + 16)));
	},

	// func (v Value) set(key string, value Value)
	"syscall/js.Value.set": (sp) => {
	Reflect.set(loadValue(sp + 8), loadString(sp + 16), loadValue(sp + 32));
	},

	// func (v Value) Index(i int) Value
	"syscall/js.Value.Index": (sp) => {
	storeValue(sp + 24, Reflect.get(loadValue(sp + 8), getInt64(sp + 16)));
	},

	// func (v Value) setIndex(i int, value Value)
	"syscall/js.Value.setIndex": (sp) => {
	Reflect.set(loadValue(sp + 8), getInt64(sp + 16), loadValue(sp + 24));
	},

	// func (v Value) call(name string, args []Value) (Value, bool)
	"syscall/js.Value.call": (sp) => {
	try {
	const v = loadValue(sp + 8);
	const m = Reflect.get(v, loadString(sp + 16));
	const args = loadSliceOfValues(sp + 32);
	storeValue(sp + 56, Reflect.apply(m, v, args));
	mem().setUint8(sp + 60, 1);
	} catch (err) {
	storeValue(sp + 56, err);
	mem().setUint8(sp + 60, 0);
	}
	},

	// func (v Value) invoke(args []Value) (Value, bool)
	"syscall/js.Value.invoke": (sp) => {
	try {
	const v = loadValue(sp + 8);
	const args = loadSliceOfValues(sp + 16);
	storeValue(sp + 40, Reflect.apply(v, undefined, args));
	mem().setUint8(sp + 44, 1);
	} catch (err) {
	storeValue(sp + 40, err);
	mem().setUint8(sp + 44, 0);
	}
	},

	// func (v Value) new(args []Value) (Value, bool)
	"syscall/js.Value.new": (sp) => {
	try {
	const v = loadValue(sp + 8);
	const args = loadSliceOfValues(sp + 16);
	storeValue(sp + 40, Reflect.construct(v, args));
	mem().setUint8(sp + 44, 1);
	} catch (err) {
	storeValue(sp + 40, err);
	mem().setUint8(sp + 44, 0);
	}
	},

	// func (v Value) Float() float64
	"syscall/js.Value.Float": (sp) => {
	mem().setFloat64(sp + 16, parseFloat(loadValue(sp + 8)), true);
	},

	// func (v Value) Int() int
	"syscall/js.Value.Int": (sp) => {
	setInt64(sp + 16, parseInt(loadValue(sp + 8)));
	},

	// func (v Value) Bool() bool
	"syscall/js.Value.Bool": (sp) => {
	mem().setUint8(sp + 16, !!loadValue(sp + 8));
	},

	// func (v Value) Length() int
	"syscall/js.Value.Length": (sp) => {
	setInt64(sp + 16, parseInt(loadValue(sp + 8).length));
	},

	// func (v Value) prepareString() (Value, int)
	"syscall/js.Value.prepareString": (sp) => {
	const str = encoder.encode(String(loadValue(sp + 8)));
	storeValue(sp + 16, str);
	setInt64(sp + 24, str.length);
	},

	// func (v Value) loadString(b []byte)
	"syscall/js.Value.loadString": (sp) => {
	const str = loadValue(sp + 8);
	loadSlice(sp + 16).set(str);
	},

	"debug": (value) => {
	console.log(value);
	},
	}
	};
	}

	async run(instance) {
	this._inst = instance;
	this._values = [undefined, null, global, this._inst.exports.mem]; // TODO: garbage collection

	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 (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 = process.env;
	go.exit = process.exit;
	WebAssembly.instantiate(fs.readFileSync(process.argv[2]), go.importObject).then((result) => {
	return go.run(result.instance);
	}).catch((err) => {
	console.error(err);
	process.exit(1);
	});
	}
	})();