github.com/prattmic/llgo-embedded@v0.0.0-20150820070356-41cfecea0e1e/third_party/gofrontend/libgo/go/os/exec_unix.go (about)

     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  // +build darwin dragonfly freebsd linux nacl netbsd openbsd solaris
     6  
     7  package os
     8  
     9  import (
    10  	"errors"
    11  	"runtime"
    12  	"syscall"
    13  	"time"
    14  )
    15  
    16  func (p *Process) wait() (ps *ProcessState, err error) {
    17  	if p.Pid == -1 {
    18  		return nil, syscall.EINVAL
    19  	}
    20  	var status syscall.WaitStatus
    21  	var rusage syscall.Rusage
    22  	pid1, e := syscall.Wait4(p.Pid, &status, 0, &rusage)
    23  	if e != nil {
    24  		return nil, NewSyscallError("wait", e)
    25  	}
    26  	if pid1 != 0 {
    27  		p.setDone()
    28  	}
    29  	ps = &ProcessState{
    30  		pid:    pid1,
    31  		status: status,
    32  		rusage: &rusage,
    33  	}
    34  	return ps, nil
    35  }
    36  
    37  var errFinished = errors.New("os: process already finished")
    38  
    39  func (p *Process) signal(sig Signal) error {
    40  	if p.Pid == -1 {
    41  		return errors.New("os: process already released")
    42  	}
    43  	if p.Pid == 0 {
    44  		return errors.New("os: process not initialized")
    45  	}
    46  	if p.done() {
    47  		return errFinished
    48  	}
    49  	s, ok := sig.(syscall.Signal)
    50  	if !ok {
    51  		return errors.New("os: unsupported signal type")
    52  	}
    53  	if e := syscall.Kill(p.Pid, s); e != nil {
    54  		if e == syscall.ESRCH {
    55  			return errFinished
    56  		}
    57  		return e
    58  	}
    59  	return nil
    60  }
    61  
    62  func (p *Process) release() error {
    63  	// NOOP for unix.
    64  	p.Pid = -1
    65  	// no need for a finalizer anymore
    66  	runtime.SetFinalizer(p, nil)
    67  	return nil
    68  }
    69  
    70  func findProcess(pid int) (p *Process, err error) {
    71  	// NOOP for unix.
    72  	return newProcess(pid, 0), nil
    73  }
    74  
    75  func (p *ProcessState) userTime() time.Duration {
    76  	return time.Duration(p.rusage.Utime.Nano()) * time.Nanosecond
    77  }
    78  
    79  func (p *ProcessState) systemTime() time.Duration {
    80  	return time.Duration(p.rusage.Stime.Nano()) * time.Nanosecond
    81  }