wasm: use wasip1 API for parameter/env passing

main.go

@@ -770,12 +770,11 @@ func Run(pkgName string, options *compileopts.Options, cmdArgs []string) error {
 // for the given emulator.
 func buildAndRun(pkgName string, config *compileopts.Config, stdout io.Writer, cmdArgs, environmentVars []string, timeout time.Duration, run func(cmd *exec.Cmd, result builder.BuildResult) error) (builder.BuildResult, error) {
 	// Determine whether we're on a system that supports environment variables
-	// and command line parameters (operating systems, WASI) or not (baremetal,
-	// WebAssembly in the browser). If we're on a system without an environment,
-	// we need to pass command line arguments and environment variables through
-	// global variables (built into the binary directly) instead of the
-	// conventional way.
-	needsEnvInVars := config.GOOS() == "js"
+	// and command line parameters (operating systems, WASI) or not (baremetal).
+	// If we're on a system without an environment, we need to pass command line
+	// arguments and environment variables through global variables (built into
+	// the binary directly) instead of the conventional way.
+	needsEnvInVars := false
 	for _, tag := range config.BuildTags() {
 		if tag == "baremetal" {
 			needsEnvInVars = true

src/runtime/nonhosted.go

@@ -1,4 +1,4 @@
-//go:build baremetal || js || wasm_unknown
+//go:build baremetal || wasm_unknown
 
 package runtime
 

src/runtime/runtime_tinygowasm.go

@@ -29,6 +29,44 @@ func proc_exit(exitcode uint32)
 //export __stdio_exit
 func __stdio_exit()
 
+var args []string
+
+//go:linkname os_runtime_args os.runtime_args
+func os_runtime_args() []string {
+	if args == nil {
+		// Read the number of args (argc) and the buffer size required to store
+		// all these args (argv).
+		var argc, argv_buf_size uint32
+		args_sizes_get(&argc, &argv_buf_size)
+		if argc == 0 {
+			return nil
+		}
+
+		// Obtain the command line arguments
+		argsSlice := make([]unsafe.Pointer, argc)
+		buf := make([]byte, argv_buf_size)
+		args_get(&argsSlice[0], unsafe.Pointer(&buf[0]))
+
+		// Convert the array of C strings to an array of Go strings.
+		args = make([]string, argc)
+		for i, cstr := range argsSlice {
+			length := strlen(cstr)
+			argString := _string{
+				length: length,
+				ptr:    (*byte)(cstr),
+			}
+			args[i] = *(*string)(unsafe.Pointer(&argString))
+		}
+	}
+	return args
+}
+
+//go:wasmimport wasi_snapshot_preview1 args_get
+func args_get(argv *unsafe.Pointer, argv_buf unsafe.Pointer) (errno uint16)
+
+//go:wasmimport wasi_snapshot_preview1 args_sizes_get
+func args_sizes_get(argc *uint32, argv_buf_size *uint32) (errno uint16)
+
 const (
 	putcharBufferSize = 120
 	stdout            = 1

src/runtime/runtime_wasip1.go

@@ -2,10 +2,6 @@
 
 package runtime
 
-import (
-	"unsafe"
-)
-
 type timeUnit int64
 
 // libc constructors
@@ -21,38 +17,6 @@ func init() {
 	__wasm_call_ctors()
 }
 
-var args []string
-
-//go:linkname os_runtime_args os.runtime_args
-func os_runtime_args() []string {
-	if args == nil {
-		// Read the number of args (argc) and the buffer size required to store
-		// all these args (argv).
-		var argc, argv_buf_size uint32
-		args_sizes_get(&argc, &argv_buf_size)
-		if argc == 0 {
-			return nil
-		}
-
-		// Obtain the command line arguments
-		argsSlice := make([]unsafe.Pointer, argc)
-		buf := make([]byte, argv_buf_size)
-		args_get(&argsSlice[0], unsafe.Pointer(&buf[0]))
-
-		// Convert the array of C strings to an array of Go strings.
-		args = make([]string, argc)
-		for i, cstr := range argsSlice {
-			length := strlen(cstr)
-			argString := _string{
-				length: length,
-				ptr:    (*byte)(cstr),
-			}
-			args[i] = *(*string)(unsafe.Pointer(&argString))
-		}
-	}
-	return args
-}
-
 func ticksToNanoseconds(ticks timeUnit) int64 {
 	return int64(ticks)
 }
@@ -97,12 +61,6 @@ func beforeExit() {
 
 // Implementations of WASI APIs
 
-//go:wasmimport wasi_snapshot_preview1 args_get
-func args_get(argv *unsafe.Pointer, argv_buf unsafe.Pointer) (errno uint16)
-
-//go:wasmimport wasi_snapshot_preview1 args_sizes_get
-func args_sizes_get(argc *uint32, argv_buf_size *uint32) (errno uint16)
-
 //go:wasmimport wasi_snapshot_preview1 clock_time_get
 func clock_time_get(clockid uint32, precision uint64, time *uint64) (errno uint16)
 

src/syscall/env_libc.go

@@ -1,4 +1,4 @@
-//go:build nintendoswitch || wasip1
+//go:build js || nintendoswitch || wasip1
 
 package syscall
 

src/syscall/errno_other.go

@@ -1,4 +1,4 @@
-//go:build !wasip1 && !wasip2
+//go:build !js && !wasip1 && !wasip2
 
 package syscall
 

src/syscall/errno_wasip1.go → src/syscall/errno_wasmlibc.go

@@ -1,4 +1,4 @@
-//go:build wasip1
+//go:build js || wasip1
 
 package syscall
 

src/syscall/syscall_libc.go

@@ -1,4 +1,4 @@
-//go:build nintendoswitch || wasip1 || wasip2
+//go:build js || nintendoswitch || wasip1 || wasip2
 
 package syscall
 

src/syscall/syscall_libc_wasi.go

@@ -1,4 +1,4 @@
-//go:build wasip1 || wasip2
+//go:build js || wasip1 || wasip2
 
 package syscall
 

src/syscall/syscall_nonhosted.go

@@ -1,4 +1,4 @@
-//go:build baremetal || js || wasm_unknown
+//go:build baremetal || wasm_unknown
 
 package syscall
 

src/syscall/tables_nonhosted.go

@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-//go:build baremetal || nintendoswitch || js || wasm_unknown
+//go:build baremetal || nintendoswitch || wasm_unknown
 
 package syscall
 

targets/wasm_exec.js

@@ -135,6 +135,8 @@
 
 	global.Go = class {
 		constructor() {
+			this.argv = ["js"];
+			this.env = {};
 			this._callbackTimeouts = new Map();
 			this._nextCallbackTimeoutID = 1;
 
@@ -235,9 +237,58 @@
 				return decoder.decode(new DataView(this._inst.exports.memory.buffer, ptr, len));
 			}
 
+			const storeStringArraySizes = (array, num_ptr, buf_size_ptr) => {
+				let buf_size = 0;
+				for (let s of array) {
+					buf_size += s.length + 1;
+				}
+				mem().setUint32(num_ptr, array.length, true);
+				mem().setUint32(buf_size_ptr, buf_size, true);
+			}
+
+			const storeStringArray = (array, ptrs_ptr, buf_ptr) => {
+				for (let s of array) {
+					// Put string data in buffer.
+					let data = encoder.encode(s);
+					let dest = new Uint8Array(this._inst.exports.memory.buffer, buf_ptr, data.length);
+					dest.set(data);
+					mem().setUint8(buf_ptr+data.length, 0);
+
+					// Put pointer to buffer in pointers array.
+					mem().setUint32(ptrs_ptr, buf_ptr, true);
+
+					// Advance to the next element in the array.
+					ptrs_ptr += 4;
+					buf_ptr += data.length + 1;
+				}
+			}
+
+			const envArray = () => {
+				let array = [];
+				for (let [key, value] of Object.entries(this.env)) {
+					array.push(`${key}=${value}`);
+				}
+				return array;
+			}
+
 			const timeOrigin = Date.now() - performance.now();
 			this.importObject = {
 				wasi_snapshot_preview1: {
+					args_sizes_get: (argc_ptr, argv_buf_size_ptr) => {
+						storeStringArraySizes(this.argv, argc_ptr, argv_buf_size_ptr);
+						return 0;
+					},
+					args_get: (argv_ptr, argv_buf_ptr) => {
+						storeStringArray(this.argv, argv_ptr, argv_buf_ptr);
+						return 0;
+					},
+					environ_get: (env_ptr, env_buf_ptr) => {
+						storeStringArray(envArray(), env_ptr, env_buf_ptr);
+					},
+					environ_sizes_get: (env_ptr, env_buf_size_ptr) => {
+						storeStringArraySizes(envArray(), env_ptr, env_buf_size_ptr);
+						return 0;
+					},
 					// https://github.com/WebAssembly/WASI/blob/main/phases/snapshot/docs.md#fd_write
 					fd_write: function(fd, iovs_ptr, iovs_len, nwritten_ptr) {
 						let nwritten = 0;
@@ -504,12 +555,14 @@
 		global.process.versions &&
 		!global.process.versions.electron
 	) {
-		if (process.argv.length != 3) {
+		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 = process.env;
 		WebAssembly.instantiate(fs.readFileSync(process.argv[2]), go.importObject).then((result) => {
 			return go.run(result.instance);
 		}).catch((err) => {