build: separate compiler and libs

compiler/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()
+}