libgo/go/os/exec_plan9.go

   1 // Copyright 2009 The Go Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style
   3 // license that can be found in the LICENSE file.
   4
   5 package os
   6
   7 import (
   8         "internal/itoa"
   9         "runtime"
  10         "syscall"
  11         "time"
  12 )
  13
  14 // The only signal values guaranteed to be present in the os package
  15 // on all systems are Interrupt (send the process an interrupt) and
  16 // Kill (force the process to exit). Interrupt is not implemented on
  17 // Windows; using it with os.Process.Signal will return an error.
  18 var (
  19         Interrupt Signal = syscall.Note("interrupt")
  20         Kill      Signal = syscall.Note("kill")
  21 )
  22
  23 func startProcess(name string, argv []string, attr *ProcAttr) (p *Process, err error) {
  24         sysattr := &syscall.ProcAttr{
  25                 Dir: attr.Dir,
  26                 Env: attr.Env,
  27                 Sys: attr.Sys,
  28         }
  29
  30         sysattr.Files = make([]uintptr, 0, len(attr.Files))
  31         for _, f := range attr.Files {
  32                 sysattr.Files = append(sysattr.Files, f.Fd())
  33         }
  34
  35         pid, h, e := syscall.StartProcess(name, argv, sysattr)
  36         if e != nil {
  37                 return nil, &PathError{Op: "fork/exec", Path: name, Err: e}
  38         }
  39
  40         return newProcess(pid, h), nil
  41 }
  42
  43 func (p *Process) writeProcFile(file string, data string) error {
  44         f, e := OpenFile("/proc/"+itoa.Itoa(p.Pid)+"/"+file, O_WRONLY, 0)
  45         if e != nil {
  46                 return e
  47         }
  48         defer f.Close()
  49         _, e = f.Write([]byte(data))
  50         return e
  51 }
  52
  53 func (p *Process) signal(sig Signal) error {
  54         if p.done() {
  55                 return ErrProcessDone
  56         }
  57         if e := p.writeProcFile("note", sig.String()); e != nil {
  58                 return NewSyscallError("signal", e)
  59         }
  60         return nil
  61 }
  62
  63 func (p *Process) kill() error {
  64         return p.signal(Kill)
  65 }
  66
  67 func (p *Process) wait() (ps *ProcessState, err error) {
  68         var waitmsg syscall.Waitmsg
  69
  70         if p.Pid == -1 {
  71                 return nil, ErrInvalid
  72         }
  73         err = syscall.WaitProcess(p.Pid, &waitmsg)
  74         if err != nil {
  75                 return nil, NewSyscallError("wait", err)
  76         }
  77
  78         p.setDone()
  79         ps = &ProcessState{
  80                 pid:    waitmsg.Pid,
  81                 status: &waitmsg,
  82         }
  83         return ps, nil
  84 }
  85
  86 func (p *Process) release() error {
  87         // NOOP for Plan 9.
  88         p.Pid = -1
  89         // no need for a finalizer anymore
  90         runtime.SetFinalizer(p, nil)
  91         return nil
  92 }
  93
  94 func findProcess(pid int) (p *Process, err error) {
  95         // NOOP for Plan 9.
  96         return newProcess(pid, 0), nil
  97 }
  98
  99 // ProcessState stores information about a process, as reported by Wait.
 100 type ProcessState struct {
 101         pid    int              // The process's id.
 102         status *syscall.Waitmsg // System-dependent status info.
 103 }
 104
 105 // Pid returns the process id of the exited process.
 106 func (p *ProcessState) Pid() int {
 107         return p.pid
 108 }
 109
 110 func (p *ProcessState) exited() bool {
 111         return p.status.Exited()
 112 }
 113
 114 func (p *ProcessState) success() bool {
 115         return p.status.ExitStatus() == 0
 116 }
 117
 118 func (p *ProcessState) sys() any {
 119         return p.status
 120 }
 121
 122 func (p *ProcessState) sysUsage() any {
 123         return p.status
 124 }
 125
 126 func (p *ProcessState) userTime() time.Duration {
 127         return time.Duration(p.status.Time[0]) * time.Millisecond
 128 }
 129
 130 func (p *ProcessState) systemTime() time.Duration {
 131         return time.Duration(p.status.Time[1]) * time.Millisecond
 132 }
 133
 134 func (p *ProcessState) String() string {
 135         if p == nil {
 136                 return "<nil>"
 137         }
 138         return "exit status: " + p.status.Msg
 139 }
 140
 141 // ExitCode returns the exit code of the exited process, or -1
 142 // if the process hasn't exited or was terminated by a signal.
 143 func (p *ProcessState) ExitCode() int {
 144         // return -1 if the process hasn't started.
 145         if p == nil {
 146                 return -1
 147         }
 148         return p.status.ExitStatus()
 149 }