patch library: syscall, os/exec

internal/lib/os/exec.go

@@ -0,0 +1,172 @@
+// Copyright 2009 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.
+
+package os
+
+import (
+	"errors"
+	"runtime"
+	"sync"
+	"sync/atomic"
+	"syscall"
+	"time"
+)
+
+// ErrProcessDone indicates a Process has finished.
+var ErrProcessDone = errors.New("os: process already finished")
+
+// Process stores the information about a process created by StartProcess.
+type Process struct {
+	Pid    int
+	handle uintptr      // handle is accessed atomically on Windows
+	isdone atomic.Bool  // process has been successfully waited on
+	sigMu  sync.RWMutex // avoid race between wait and signal
+}
+
+func newProcess(pid int, handle uintptr) *Process {
+	p := &Process{Pid: pid, handle: handle}
+	runtime.SetFinalizer(p, (*Process).Release)
+	return p
+}
+
+func (p *Process) setDone() {
+	p.isdone.Store(true)
+}
+
+func (p *Process) done() bool {
+	return p.isdone.Load()
+}
+
+// ProcAttr holds the attributes that will be applied to a new process
+// started by StartProcess.
+type ProcAttr struct {
+	// If Dir is non-empty, the child changes into the directory before
+	// creating the process.
+	Dir string
+	// If Env is non-nil, it gives the environment variables for the
+	// new process in the form returned by Environ.
+	// If it is nil, the result of Environ will be used.
+	Env []string
+	// Files specifies the open files inherited by the new process. The
+	// first three entries correspond to standard input, standard output, and
+	// standard error. An implementation may support additional entries,
+	// depending on the underlying operating system. A nil entry corresponds
+	// to that file being closed when the process starts.
+	// On Unix systems, StartProcess will change these File values
+	// to blocking mode, which means that SetDeadline will stop working
+	// and calling Close will not interrupt a Read or Write.
+	Files []*File
+
+	// Operating system-specific process creation attributes.
+	// Note that setting this field means that your program
+	// may not execute properly or even compile on some
+	// operating systems.
+	Sys *syscall.SysProcAttr
+}
+
+// A Signal represents an operating system signal.
+// The usual underlying implementation is operating system-dependent:
+// on Unix it is syscall.Signal.
+type Signal interface {
+	String() string
+	Signal() // to distinguish from other Stringers
+}
+
+// FindProcess looks for a running process by its pid.
+//
+// The Process it returns can be used to obtain information
+// about the underlying operating system process.
+//
+// On Unix systems, FindProcess always succeeds and returns a Process
+// for the given pid, regardless of whether the process exists. To test whether
+// the process actually exists, see whether p.Signal(syscall.Signal(0)) reports
+// an error.
+func FindProcess(pid int) (*Process, error) {
+	return findProcess(pid)
+}
+
+// StartProcess starts a new process with the program, arguments and attributes
+// specified by name, argv and attr. The argv slice will become os.Args in the
+// new process, so it normally starts with the program name.
+//
+// If the calling goroutine has locked the operating system thread
+// with runtime.LockOSThread and modified any inheritable OS-level
+// thread state (for example, Linux or Plan 9 name spaces), the new
+// process will inherit the caller's thread state.
+//
+// StartProcess is a low-level interface. The os/exec package provides
+// higher-level interfaces.
+//
+// If there is an error, it will be of type *PathError.
+func StartProcess(name string, argv []string, attr *ProcAttr) (*Process, error) {
+	return startProcess(name, argv, attr)
+}
+
+// Release releases any resources associated with the Process p,
+// rendering it unusable in the future.
+// Release only needs to be called if Wait is not.
+func (p *Process) Release() error {
+	return p.release()
+}
+
+// Kill causes the Process to exit immediately. Kill does not wait until
+// the Process has actually exited. This only kills the Process itself,
+// not any other processes it may have started.
+func (p *Process) Kill() error {
+	return p.kill()
+}
+
+// Wait waits for the Process to exit, and then returns a
+// ProcessState describing its status and an error, if any.
+// Wait releases any resources associated with the Process.
+// On most operating systems, the Process must be a child
+// of the current process or an error will be returned.
+func (p *Process) Wait() (*ProcessState, error) {
+	return p.wait()
+}
+
+// Signal sends a signal to the Process.
+// Sending Interrupt on Windows is not implemented.
+func (p *Process) Signal(sig Signal) error {
+	return p.signal(sig)
+}
+
+// UserTime returns the user CPU time of the exited process and its children.
+func (p *ProcessState) UserTime() time.Duration {
+	return p.userTime()
+}
+
+// SystemTime returns the system CPU time of the exited process and its children.
+func (p *ProcessState) SystemTime() time.Duration {
+	return p.systemTime()
+}
+
+// Exited reports whether the program has exited.
+// On Unix systems this reports true if the program exited due to calling exit,
+// but false if the program terminated due to a signal.
+func (p *ProcessState) Exited() bool {
+	return p.exited()
+}
+
+// Success reports whether the program exited successfully,
+// such as with exit status 0 on Unix.
+func (p *ProcessState) Success() bool {
+	return p.success()
+}
+
+// Sys returns system-dependent exit information about
+// the process. Convert it to the appropriate underlying
+// type, such as syscall.WaitStatus on Unix, to access its contents.
+func (p *ProcessState) Sys() any {
+	return p.sys()
+}
+
+// SysUsage returns system-dependent resource usage information about
+// the exited process. Convert it to the appropriate underlying
+// type, such as *syscall.Rusage on Unix, to access its contents.
+// (On Unix, *syscall.Rusage matches struct rusage as defined in the
+// getrusage(2) manual page.)
+func (p *ProcessState) SysUsage() any {
+	return p.sysUsage()
+}

internal/lib/os/exec/exec.go

@@ -0,0 +1,22 @@
+/*
+ * Copyright (c) 2024 The GoPlus Authors (goplus.org). All rights reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package exec
+
+// llgo:skipall
+import (
+	_ "unsafe"
+)

internal/lib/os/exec/lp_plan9.go

@@ -0,0 +1,66 @@
+// Copyright 2011 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.
+
+package exec
+
+import (
+	"errors"
+	"io/fs"
+	"os"
+	"path/filepath"
+	"strings"
+)
+
+// ErrNotFound is the error resulting if a path search failed to find an executable file.
+var ErrNotFound = errors.New("executable file not found in $path")
+
+func findExecutable(file string) error {
+	d, err := os.Stat(file)
+	if err != nil {
+		return err
+	}
+	if m := d.Mode(); !m.IsDir() && m&0111 != 0 {
+		return nil
+	}
+	return fs.ErrPermission
+}
+
+// LookPath searches for an executable named file in the
+// directories named by the path environment variable.
+// If file begins with "/", "#", "./", or "../", it is tried
+// directly and the path is not consulted.
+// On success, the result is an absolute path.
+//
+// In older versions of Go, LookPath could return a path relative to the current directory.
+// As of Go 1.19, LookPath will instead return that path along with an error satisfying
+// errors.Is(err, ErrDot). See the package documentation for more details.
+func LookPath(file string) (string, error) {
+	// skip the path lookup for these prefixes
+	skip := []string{"/", "#", "./", "../"}
+
+	for _, p := range skip {
+		if strings.HasPrefix(file, p) {
+			err := findExecutable(file)
+			if err == nil {
+				return file, nil
+			}
+			return "", &Error{file, err}
+		}
+	}
+
+	path := os.Getenv("path")
+	for _, dir := range filepath.SplitList(path) {
+		path := filepath.Join(dir, file)
+		if err := findExecutable(path); err == nil {
+			if !filepath.IsAbs(path) {
+				if execerrdot.Value() != "0" {
+					return path, &Error{file, ErrDot}
+				}
+				execerrdot.IncNonDefault()
+			}
+			return path, nil
+		}
+	}
+	return "", &Error{file, ErrNotFound}
+}

internal/lib/os/exec/lp_unix.go

@@ -0,0 +1,82 @@
+// Copyright 2010 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.
+
+//go:build unix
+
+package exec
+
+import (
+	"errors"
+)
+
+// ErrNotFound is the error resulting if a path search failed to find an executable file.
+var ErrNotFound = errors.New("executable file not found in $PATH")
+
+func findExecutable(file string) error {
+	/* TODO(xsw):
+	d, err := os.Stat(file)
+	if err != nil {
+		return err
+	}
+	m := d.Mode()
+	if m.IsDir() {
+		return syscall.EISDIR
+	}
+	err = unix.Eaccess(file, unix.X_OK)
+	// ENOSYS means Eaccess is not available or not implemented.
+	// EPERM can be returned by Linux containers employing seccomp.
+	// In both cases, fall back to checking the permission bits.
+	if err == nil || (err != syscall.ENOSYS && err != syscall.EPERM) {
+		return err
+	}
+	if m&0111 != 0 {
+		return nil
+	}
+	return fs.ErrPermission
+	*/
+	panic("todo: exec.findExecutable")
+}
+
+// LookPath searches for an executable named file in the
+// directories named by the PATH environment variable.
+// If file contains a slash, it is tried directly and the PATH is not consulted.
+// Otherwise, on success, the result is an absolute path.
+//
+// In older versions of Go, LookPath could return a path relative to the current directory.
+// As of Go 1.19, LookPath will instead return that path along with an error satisfying
+// errors.Is(err, ErrDot). See the package documentation for more details.
+func LookPath(file string) (string, error) {
+	/* TODO(xsw):
+	// NOTE(rsc): I wish we could use the Plan 9 behavior here
+	// (only bypass the path if file begins with / or ./ or ../)
+	// but that would not match all the Unix shells.
+
+	if strings.Contains(file, "/") {
+		err := findExecutable(file)
+		if err == nil {
+			return file, nil
+		}
+		return "", &Error{file, err}
+	}
+	path := os.Getenv("PATH")
+	for _, dir := range filepath.SplitList(path) {
+		if dir == "" {
+			// Unix shell semantics: path element "" means "."
+			dir = "."
+		}
+		path := filepath.Join(dir, file)
+		if err := findExecutable(path); err == nil {
+			if !filepath.IsAbs(path) {
+				if execerrdot.Value() != "0" {
+					return path, &Error{file, ErrDot}
+				}
+				execerrdot.IncNonDefault()
+			}
+			return path, nil
+		}
+	}
+	return "", &Error{file, ErrNotFound}
+	*/
+	panic("todo: exec.LookPath")
+}

internal/lib/os/exec/lp_wasm.go

@@ -0,0 +1,23 @@
+// 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.
+
+//go:build wasm
+
+package exec
+
+import (
+	"errors"
+)
+
+// ErrNotFound is the error resulting if a path search failed to find an executable file.
+var ErrNotFound = errors.New("executable file not found in $PATH")
+
+// LookPath searches for an executable named file in the
+// directories named by the PATH environment variable.
+// If file contains a slash, it is tried directly and the PATH is not consulted.
+// The result may be an absolute path or a path relative to the current directory.
+func LookPath(file string) (string, error) {
+	// Wasm can not execute processes, so act as if there are no executables at all.
+	return "", &Error{file, ErrNotFound}
+}

internal/lib/os/exec/lp_windows.go

@@ -0,0 +1,145 @@
+// Copyright 2010 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.
+
+package exec
+
+import (
+	"errors"
+	"io/fs"
+	"os"
+	"path/filepath"
+	"strings"
+	"syscall"
+)
+
+// ErrNotFound is the error resulting if a path search failed to find an executable file.
+var ErrNotFound = errors.New("executable file not found in %PATH%")
+
+func chkStat(file string) error {
+	d, err := os.Stat(file)
+	if err != nil {
+		return err
+	}
+	if d.IsDir() {
+		return fs.ErrPermission
+	}
+	return nil
+}
+
+func hasExt(file string) bool {
+	i := strings.LastIndex(file, ".")
+	if i < 0 {
+		return false
+	}
+	return strings.LastIndexAny(file, `:\/`) < i
+}
+
+func findExecutable(file string, exts []string) (string, error) {
+	if len(exts) == 0 {
+		return file, chkStat(file)
+	}
+	if hasExt(file) {
+		if chkStat(file) == nil {
+			return file, nil
+		}
+	}
+	for _, e := range exts {
+		if f := file + e; chkStat(f) == nil {
+			return f, nil
+		}
+	}
+	return "", fs.ErrNotExist
+}
+
+// LookPath searches for an executable named file in the
+// directories named by the PATH environment variable.
+// LookPath also uses PATHEXT environment variable to match
+// a suitable candidate.
+// If file contains a slash, it is tried directly and the PATH is not consulted.
+// Otherwise, on success, the result is an absolute path.
+//
+// In older versions of Go, LookPath could return a path relative to the current directory.
+// As of Go 1.19, LookPath will instead return that path along with an error satisfying
+// errors.Is(err, ErrDot). See the package documentation for more details.
+func LookPath(file string) (string, error) {
+	var exts []string
+	x := os.Getenv(`PATHEXT`)
+	if x != "" {
+		for _, e := range strings.Split(strings.ToLower(x), `;`) {
+			if e == "" {
+				continue
+			}
+			if e[0] != '.' {
+				e = "." + e
+			}
+			exts = append(exts, e)
+		}
+	} else {
+		exts = []string{".com", ".exe", ".bat", ".cmd"}
+	}
+
+	if strings.ContainsAny(file, `:\/`) {
+		f, err := findExecutable(file, exts)
+		if err == nil {
+			return f, nil
+		}
+		return "", &Error{file, err}
+	}
+
+	// On Windows, creating the NoDefaultCurrentDirectoryInExePath
+	// environment variable (with any value or no value!) signals that
+	// path lookups should skip the current directory.
+	// In theory we are supposed to call NeedCurrentDirectoryForExePathW
+	// "as the registry location of this environment variable can change"
+	// but that seems exceedingly unlikely: it would break all users who
+	// have configured their environment this way!
+	// https://docs.microsoft.com/en-us/windows/win32/api/processenv/nf-processenv-needcurrentdirectoryforexepathw
+	// See also go.dev/issue/43947.
+	var (
+		dotf   string
+		dotErr error
+	)
+	if _, found := syscall.Getenv("NoDefaultCurrentDirectoryInExePath"); !found {
+		if f, err := findExecutable(filepath.Join(".", file), exts); err == nil {
+			if execerrdot.Value() == "0" {
+				execerrdot.IncNonDefault()
+				return f, nil
+			}
+			dotf, dotErr = f, &Error{file, ErrDot}
+		}
+	}
+
+	path := os.Getenv("path")
+	for _, dir := range filepath.SplitList(path) {
+		if f, err := findExecutable(filepath.Join(dir, file), exts); err == nil {
+			if dotErr != nil {
+				// https://go.dev/issue/53536: if we resolved a relative path implicitly,
+				// and it is the same executable that would be resolved from the explicit %PATH%,
+				// prefer the explicit name for the executable (and, likely, no error) instead
+				// of the equivalent implicit name with ErrDot.
+				//
+				// Otherwise, return the ErrDot for the implicit path as soon as we find
+				// out that the explicit one doesn't match.
+				dotfi, dotfiErr := os.Lstat(dotf)
+				fi, fiErr := os.Lstat(f)
+				if dotfiErr != nil || fiErr != nil || !os.SameFile(dotfi, fi) {
+					return dotf, dotErr
+				}
+			}
+
+			if !filepath.IsAbs(f) {
+				if execerrdot.Value() != "0" {
+					return f, &Error{file, ErrDot}
+				}
+				execerrdot.IncNonDefault()
+			}
+			return f, nil
+		}
+	}
+
+	if dotErr != nil {
+		return dotf, dotErr
+	}
+	return "", &Error{file, ErrNotFound}
+}

internal/lib/os/exec_plan9.go

@@ -0,0 +1,149 @@
+// Copyright 2009 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.
+
+package os
+
+import (
+	"internal/itoa"
+	"runtime"
+	"syscall"
+	"time"
+)
+
+// The only signal values guaranteed to be present in the os package
+// on all systems are Interrupt (send the process an interrupt) and
+// Kill (force the process to exit). Interrupt is not implemented on
+// Windows; using it with os.Process.Signal will return an error.
+var (
+	Interrupt Signal = syscall.Note("interrupt")
+	Kill      Signal = syscall.Note("kill")
+)
+
+func startProcess(name string, argv []string, attr *ProcAttr) (p *Process, err error) {
+	sysattr := &syscall.ProcAttr{
+		Dir: attr.Dir,
+		Env: attr.Env,
+		Sys: attr.Sys,
+	}
+
+	sysattr.Files = make([]uintptr, 0, len(attr.Files))
+	for _, f := range attr.Files {
+		sysattr.Files = append(sysattr.Files, f.Fd())
+	}
+
+	pid, h, e := syscall.StartProcess(name, argv, sysattr)
+	if e != nil {
+		return nil, &PathError{Op: "fork/exec", Path: name, Err: e}
+	}
+
+	return newProcess(pid, h), nil
+}
+
+func (p *Process) writeProcFile(file string, data string) error {
+	f, e := OpenFile("/proc/"+itoa.Itoa(p.Pid)+"/"+file, O_WRONLY, 0)
+	if e != nil {
+		return e
+	}
+	defer f.Close()
+	_, e = f.Write([]byte(data))
+	return e
+}
+
+func (p *Process) signal(sig Signal) error {
+	if p.done() {
+		return ErrProcessDone
+	}
+	if e := p.writeProcFile("note", sig.String()); e != nil {
+		return NewSyscallError("signal", e)
+	}
+	return nil
+}
+
+func (p *Process) kill() error {
+	return p.signal(Kill)
+}
+
+func (p *Process) wait() (ps *ProcessState, err error) {
+	var waitmsg syscall.Waitmsg
+
+	if p.Pid == -1 {
+		return nil, ErrInvalid
+	}
+	err = syscall.WaitProcess(p.Pid, &waitmsg)
+	if err != nil {
+		return nil, NewSyscallError("wait", err)
+	}
+
+	p.setDone()
+	ps = &ProcessState{
+		pid:    waitmsg.Pid,
+		status: &waitmsg,
+	}
+	return ps, nil
+}
+
+func (p *Process) release() error {
+	// NOOP for Plan 9.
+	p.Pid = -1
+	// no need for a finalizer anymore
+	runtime.SetFinalizer(p, nil)
+	return nil
+}
+
+func findProcess(pid int) (p *Process, err error) {
+	// NOOP for Plan 9.
+	return newProcess(pid, 0), nil
+}
+
+// ProcessState stores information about a process, as reported by Wait.
+type ProcessState struct {
+	pid    int              // The process's id.
+	status *syscall.Waitmsg // System-dependent status info.
+}
+
+// Pid returns the process id of the exited process.
+func (p *ProcessState) Pid() int {
+	return p.pid
+}
+
+func (p *ProcessState) exited() bool {
+	return p.status.Exited()
+}
+
+func (p *ProcessState) success() bool {
+	return p.status.ExitStatus() == 0
+}
+
+func (p *ProcessState) sys() any {
+	return p.status
+}
+
+func (p *ProcessState) sysUsage() any {
+	return p.status
+}
+
+func (p *ProcessState) userTime() time.Duration {
+	return time.Duration(p.status.Time[0]) * time.Millisecond
+}
+
+func (p *ProcessState) systemTime() time.Duration {
+	return time.Duration(p.status.Time[1]) * time.Millisecond
+}
+
+func (p *ProcessState) String() string {
+	if p == nil {
+		return "<nil>"
+	}
+	return "exit status: " + p.status.Msg
+}
+
+// ExitCode returns the exit code of the exited process, or -1
+// if the process hasn't exited or was terminated by a signal.
+func (p *ProcessState) ExitCode() int {
+	// return -1 if the process hasn't started.
+	if p == nil {
+		return -1
+	}
+	return p.status.ExitStatus()
+}

internal/lib/os/exec_posix.go

@@ -0,0 +1,139 @@
+// Copyright 2009 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.
+
+//go:build unix || (js && wasm) || wasip1 || windows
+
+package os
+
+import (
+	"syscall"
+)
+
+// The only signal values guaranteed to be present in the os package on all
+// systems are os.Interrupt (send the process an interrupt) and os.Kill (force
+// the process to exit). On Windows, sending os.Interrupt to a process with
+// os.Process.Signal is not implemented; it will return an error instead of
+// sending a signal.
+var (
+	Interrupt Signal = syscall.SIGINT
+	Kill      Signal = syscall.SIGKILL
+)
+
+func startProcess(name string, argv []string, attr *ProcAttr) (p *Process, err error) {
+	/* TODO(xsw):
+	// If there is no SysProcAttr (ie. no Chroot or changed
+	// UID/GID), double-check existence of the directory we want
+	// to chdir into. We can make the error clearer this way.
+	if attr != nil && attr.Sys == nil && attr.Dir != "" {
+		if _, err := Stat(attr.Dir); err != nil {
+			pe := err.(*PathError)
+			pe.Op = "chdir"
+			return nil, pe
+		}
+	}
+
+	sysattr := &syscall.ProcAttr{
+		Dir: attr.Dir,
+		Env: attr.Env,
+		Sys: attr.Sys,
+	}
+	if sysattr.Env == nil {
+		sysattr.Env, err = execenv.Default(sysattr.Sys)
+		if err != nil {
+			return nil, err
+		}
+	}
+	sysattr.Files = make([]uintptr, 0, len(attr.Files))
+	for _, f := range attr.Files {
+		sysattr.Files = append(sysattr.Files, f.Fd())
+	}
+
+	pid, h, e := syscall.StartProcess(name, argv, sysattr)
+
+	// Make sure we don't run the finalizers of attr.Files.
+	runtime.KeepAlive(attr)
+
+	if e != nil {
+		return nil, &PathError{Op: "fork/exec", Path: name, Err: e}
+	}
+
+	return newProcess(pid, h), nil
+	*/
+	panic("todo: os.startProcess")
+}
+
+func (p *Process) kill() error {
+	return p.Signal(Kill)
+}
+
+// ProcessState stores information about a process, as reported by Wait.
+type ProcessState struct {
+	pid    int                // The process's id.
+	status syscall.WaitStatus // System-dependent status info.
+	rusage *syscall.Rusage
+}
+
+// Pid returns the process id of the exited process.
+func (p *ProcessState) Pid() int {
+	return p.pid
+}
+
+func (p *ProcessState) exited() bool {
+	return p.status.Exited()
+}
+
+func (p *ProcessState) success() bool {
+	return p.status.ExitStatus() == 0
+}
+
+func (p *ProcessState) sys() any {
+	return p.status
+}
+
+func (p *ProcessState) sysUsage() any {
+	return p.rusage
+}
+
+func (p *ProcessState) String() string {
+	/* TODO(xsw):
+	if p == nil {
+		return "<nil>"
+	}
+	status := p.Sys().(syscall.WaitStatus)
+	res := ""
+	switch {
+	case status.Exited():
+		code := status.ExitStatus()
+		if runtime.GOOS == "windows" && uint(code) >= 1<<16 { // windows uses large hex numbers
+			res = "exit status " + uitox(uint(code))
+		} else { // unix systems use small decimal integers
+			res = "exit status " + itoa.Itoa(code) // unix
+		}
+	case status.Signaled():
+		res = "signal: " + status.Signal().String()
+	case status.Stopped():
+		res = "stop signal: " + status.StopSignal().String()
+		if status.StopSignal() == syscall.SIGTRAP && status.TrapCause() != 0 {
+			res += " (trap " + itoa.Itoa(status.TrapCause()) + ")"
+		}
+	case status.Continued():
+		res = "continued"
+	}
+	if status.CoreDump() {
+		res += " (core dumped)"
+	}
+	return res
+	*/
+	panic("todo: os.ProcessState.String")
+}
+
+// ExitCode returns the exit code of the exited process, or -1
+// if the process hasn't exited or was terminated by a signal.
+func (p *ProcessState) ExitCode() int {
+	// return -1 if the process hasn't started.
+	if p == nil {
+		return -1
+	}
+	return p.status.ExitStatus()
+}

internal/lib/os/exec_unix.go

@@ -0,0 +1,109 @@
+// Copyright 2009 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.
+
+//go:build unix || (js && wasm) || wasip1
+
+package os
+
+import (
+	"errors"
+	"runtime"
+	"syscall"
+	"time"
+)
+
+func (p *Process) wait() (ps *ProcessState, err error) {
+	/* TODO(xsw):
+	if p.Pid == -1 {
+		return nil, syscall.EINVAL
+	}
+
+	// If we can block until Wait4 will succeed immediately, do so.
+	ready, err := p.blockUntilWaitable()
+	if err != nil {
+		return nil, err
+	}
+	if ready {
+		// Mark the process done now, before the call to Wait4,
+		// so that Process.signal will not send a signal.
+		p.setDone()
+		// Acquire a write lock on sigMu to wait for any
+		// active call to the signal method to complete.
+		p.sigMu.Lock()
+		p.sigMu.Unlock()
+	}
+
+	var (
+		status syscall.WaitStatus
+		rusage syscall.Rusage
+		pid1   int
+		e      error
+	)
+	for {
+		pid1, e = syscall.Wait4(p.Pid, &status, 0, &rusage)
+		if e != syscall.EINTR {
+			break
+		}
+	}
+	if e != nil {
+		return nil, NewSyscallError("wait", e)
+	}
+	if pid1 != 0 {
+		p.setDone()
+	}
+	ps = &ProcessState{
+		pid:    pid1,
+		status: status,
+		rusage: &rusage,
+	}
+	return ps, nil
+	*/
+	panic("todo: os.Process.wait")
+}
+
+func (p *Process) signal(sig Signal) error {
+	if p.Pid == -1 {
+		return errors.New("os: process already released")
+	}
+	if p.Pid == 0 {
+		return errors.New("os: process not initialized")
+	}
+	p.sigMu.RLock()
+	defer p.sigMu.RUnlock()
+	if p.done() {
+		return ErrProcessDone
+	}
+	s, ok := sig.(syscall.Signal)
+	if !ok {
+		return errors.New("os: unsupported signal type")
+	}
+	if e := syscall.Kill(p.Pid, s); e != nil {
+		if e == syscall.ESRCH {
+			return ErrProcessDone
+		}
+		return e
+	}
+	return nil
+}
+
+func (p *Process) release() error {
+	// NOOP for unix.
+	p.Pid = -1
+	// no need for a finalizer anymore
+	runtime.SetFinalizer(p, nil)
+	return nil
+}
+
+func findProcess(pid int) (p *Process, err error) {
+	// NOOP for unix.
+	return newProcess(pid, 0), nil
+}
+
+func (p *ProcessState) userTime() time.Duration {
+	return time.Duration(p.rusage.Utime.Nano()) * time.Nanosecond
+}
+
+func (p *ProcessState) systemTime() time.Duration {
+	return time.Duration(p.rusage.Stime.Nano()) * time.Nanosecond
+}

internal/lib/os/exec_windows.go

@@ -0,0 +1,183 @@
+// Copyright 2009 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.
+
+package os
+
+import (
+	"internal/syscall/windows"
+	"runtime"
+	"sync/atomic"
+	"syscall"
+	"time"
+)
+
+func (p *Process) wait() (ps *ProcessState, err error) {
+	/* TODO(xsw):
+	handle := atomic.LoadUintptr(&p.handle)
+	s, e := syscall.WaitForSingleObject(syscall.Handle(handle), syscall.INFINITE)
+	switch s {
+	case syscall.WAIT_OBJECT_0:
+		break
+	case syscall.WAIT_FAILED:
+		return nil, NewSyscallError("WaitForSingleObject", e)
+	default:
+		return nil, errors.New("os: unexpected result from WaitForSingleObject")
+	}
+	var ec uint32
+	e = syscall.GetExitCodeProcess(syscall.Handle(handle), &ec)
+	if e != nil {
+		return nil, NewSyscallError("GetExitCodeProcess", e)
+	}
+	var u syscall.Rusage
+	e = syscall.GetProcessTimes(syscall.Handle(handle), &u.CreationTime, &u.ExitTime, &u.KernelTime, &u.UserTime)
+	if e != nil {
+		return nil, NewSyscallError("GetProcessTimes", e)
+	}
+	p.setDone()
+	// NOTE(brainman): It seems that sometimes process is not dead
+	// when WaitForSingleObject returns. But we do not know any
+	// other way to wait for it. Sleeping for a while seems to do
+	// the trick sometimes.
+	// See https://golang.org/issue/25965 for details.
+	defer time.Sleep(5 * time.Millisecond)
+	defer p.Release()
+	return &ProcessState{p.Pid, syscall.WaitStatus{ExitCode: ec}, &u}, nil
+	*/
+	panic("todo: os.Process.wait")
+}
+
+func (p *Process) signal(sig Signal) error {
+	handle := atomic.LoadUintptr(&p.handle)
+	if handle == uintptr(syscall.InvalidHandle) {
+		return syscall.EINVAL
+	}
+	if p.done() {
+		return ErrProcessDone
+	}
+	if sig == Kill {
+		var terminationHandle syscall.Handle
+		e := syscall.DuplicateHandle(^syscall.Handle(0), syscall.Handle(handle), ^syscall.Handle(0), &terminationHandle, syscall.PROCESS_TERMINATE, false, 0)
+		if e != nil {
+			return NewSyscallError("DuplicateHandle", e)
+		}
+		runtime.KeepAlive(p)
+		defer syscall.CloseHandle(terminationHandle)
+		e = syscall.TerminateProcess(syscall.Handle(terminationHandle), 1)
+		return NewSyscallError("TerminateProcess", e)
+	}
+	// TODO(rsc): Handle Interrupt too?
+	return syscall.Errno(syscall.EWINDOWS)
+}
+
+func (p *Process) release() error {
+	handle := atomic.SwapUintptr(&p.handle, uintptr(syscall.InvalidHandle))
+	if handle == uintptr(syscall.InvalidHandle) {
+		return syscall.EINVAL
+	}
+	e := syscall.CloseHandle(syscall.Handle(handle))
+	if e != nil {
+		return NewSyscallError("CloseHandle", e)
+	}
+	// no need for a finalizer anymore
+	runtime.SetFinalizer(p, nil)
+	return nil
+}
+
+func findProcess(pid int) (p *Process, err error) {
+	const da = syscall.STANDARD_RIGHTS_READ |
+		syscall.PROCESS_QUERY_INFORMATION | syscall.SYNCHRONIZE
+	h, e := syscall.OpenProcess(da, false, uint32(pid))
+	if e != nil {
+		return nil, NewSyscallError("OpenProcess", e)
+	}
+	return newProcess(pid, uintptr(h)), nil
+}
+
+func init() {
+	cmd := windows.UTF16PtrToString(syscall.GetCommandLine())
+	if len(cmd) == 0 {
+		arg0, _ := Executable()
+		Args = []string{arg0}
+	} else {
+		Args = commandLineToArgv(cmd)
+	}
+}
+
+// appendBSBytes appends n '\\' bytes to b and returns the resulting slice.
+func appendBSBytes(b []byte, n int) []byte {
+	for ; n > 0; n-- {
+		b = append(b, '\\')
+	}
+	return b
+}
+
+// readNextArg splits command line string cmd into next
+// argument and command line remainder.
+func readNextArg(cmd string) (arg []byte, rest string) {
+	var b []byte
+	var inquote bool
+	var nslash int
+	for ; len(cmd) > 0; cmd = cmd[1:] {
+		c := cmd[0]
+		switch c {
+		case ' ', '\t':
+			if !inquote {
+				return appendBSBytes(b, nslash), cmd[1:]
+			}
+		case '"':
+			b = appendBSBytes(b, nslash/2)
+			if nslash%2 == 0 {
+				// use "Prior to 2008" rule from
+				// http://daviddeley.com/autohotkey/parameters/parameters.htm
+				// section 5.2 to deal with double double quotes
+				if inquote && len(cmd) > 1 && cmd[1] == '"' {
+					b = append(b, c)
+					cmd = cmd[1:]
+				}
+				inquote = !inquote
+			} else {
+				b = append(b, c)
+			}
+			nslash = 0
+			continue
+		case '\\':
+			nslash++
+			continue
+		}
+		b = appendBSBytes(b, nslash)
+		nslash = 0
+		b = append(b, c)
+	}
+	return appendBSBytes(b, nslash), ""
+}
+
+// commandLineToArgv splits a command line into individual argument
+// strings, following the Windows conventions documented
+// at http://daviddeley.com/autohotkey/parameters/parameters.htm#WINARGV
+func commandLineToArgv(cmd string) []string {
+	var args []string
+	for len(cmd) > 0 {
+		if cmd[0] == ' ' || cmd[0] == '\t' {
+			cmd = cmd[1:]
+			continue
+		}
+		var arg []byte
+		arg, cmd = readNextArg(cmd)
+		args = append(args, string(arg))
+	}
+	return args
+}
+
+func ftToDuration(ft *syscall.Filetime) time.Duration {
+	n := int64(ft.HighDateTime)<<32 + int64(ft.LowDateTime) // in 100-nanosecond intervals
+	return time.Duration(n*100) * time.Nanosecond
+}
+
+func (p *ProcessState) userTime() time.Duration {
+	return ftToDuration(&p.rusage.UserTime)
+}
+
+func (p *ProcessState) systemTime() time.Duration {
+	return ftToDuration(&p.rusage.KernelTime)
+}

internal/lib/os/os.go

@@ -147,7 +147,11 @@ func Clearenv()
 
 // TODO(xsw):
 // func DirFS(dir string) fs.FS
-// func Environ() []string
+
+func Environ() []string {
+	panic("todo: os.Environ")
+}
+
 // func Executable() (string, error)
 
 func Exit(code int) {
@@ -282,7 +286,10 @@ func Mkdir(name string, perm FileMode) error {
 // func MkdirAll(path string, perm FileMode) error
 // func MkdirTemp(dir, pattern string) (string, error)
 // func NewSyscallError(syscall string, err error) error
-// func Pipe() (r *File, w *File, err error)
+func Pipe() (r *File, w *File, err error) {
+	panic("todo: os.Pipe")
+}
+
 // func ReadFile(name string) ([]byte, error)
 
 func Readlink(name string) (string, error) {