github.com/spotify/syslog-redirector-golang@v0.0.0-20140320174030-4859f03d829a/src/pkg/os/exec_windows.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  package os
     6  
     7  import (
     8  	"errors"
     9  	"runtime"
    10  	"syscall"
    11  	"time"
    12  	"unsafe"
    13  )
    14  
    15  func (p *Process) wait() (ps *ProcessState, err error) {
    16  	s, e := syscall.WaitForSingleObject(syscall.Handle(p.handle), syscall.INFINITE)
    17  	switch s {
    18  	case syscall.WAIT_OBJECT_0:
    19  		break
    20  	case syscall.WAIT_FAILED:
    21  		return nil, NewSyscallError("WaitForSingleObject", e)
    22  	default:
    23  		return nil, errors.New("os: unexpected result from WaitForSingleObject")
    24  	}
    25  	var ec uint32
    26  	e = syscall.GetExitCodeProcess(syscall.Handle(p.handle), &ec)
    27  	if e != nil {
    28  		return nil, NewSyscallError("GetExitCodeProcess", e)
    29  	}
    30  	var u syscall.Rusage
    31  	e = syscall.GetProcessTimes(syscall.Handle(p.handle), &u.CreationTime, &u.ExitTime, &u.KernelTime, &u.UserTime)
    32  	if e != nil {
    33  		return nil, NewSyscallError("GetProcessTimes", e)
    34  	}
    35  	p.setDone()
    36  	// NOTE(brainman): It seems that sometimes process is not dead
    37  	// when WaitForSingleObject returns. But we do not know any
    38  	// other way to wait for it. Sleeping for a while seems to do
    39  	// the trick sometimes. So we will sleep and smell the roses.
    40  	defer time.Sleep(5 * time.Millisecond)
    41  	defer p.Release()
    42  	return &ProcessState{p.Pid, syscall.WaitStatus{ExitCode: ec}, &u}, nil
    43  }
    44  
    45  func terminateProcess(pid, exitcode int) error {
    46  	h, e := syscall.OpenProcess(syscall.PROCESS_TERMINATE, false, uint32(pid))
    47  	if e != nil {
    48  		return NewSyscallError("OpenProcess", e)
    49  	}
    50  	defer syscall.CloseHandle(h)
    51  	e = syscall.TerminateProcess(h, uint32(exitcode))
    52  	return NewSyscallError("TerminateProcess", e)
    53  }
    54  
    55  func (p *Process) signal(sig Signal) error {
    56  	if p.done() {
    57  		return errors.New("os: process already finished")
    58  	}
    59  	if sig == Kill {
    60  		return terminateProcess(p.Pid, 1)
    61  	}
    62  	// TODO(rsc): Handle Interrupt too?
    63  	return syscall.Errno(syscall.EWINDOWS)
    64  }
    65  
    66  func (p *Process) release() error {
    67  	if p.handle == uintptr(syscall.InvalidHandle) {
    68  		return syscall.EINVAL
    69  	}
    70  	e := syscall.CloseHandle(syscall.Handle(p.handle))
    71  	if e != nil {
    72  		return NewSyscallError("CloseHandle", e)
    73  	}
    74  	p.handle = uintptr(syscall.InvalidHandle)
    75  	// no need for a finalizer anymore
    76  	runtime.SetFinalizer(p, nil)
    77  	return nil
    78  }
    79  
    80  func findProcess(pid int) (p *Process, err error) {
    81  	const da = syscall.STANDARD_RIGHTS_READ |
    82  		syscall.PROCESS_QUERY_INFORMATION | syscall.SYNCHRONIZE
    83  	h, e := syscall.OpenProcess(da, false, uint32(pid))
    84  	if e != nil {
    85  		return nil, NewSyscallError("OpenProcess", e)
    86  	}
    87  	return newProcess(pid, uintptr(h)), nil
    88  }
    89  
    90  func init() {
    91  	var argc int32
    92  	cmd := syscall.GetCommandLine()
    93  	argv, e := syscall.CommandLineToArgv(cmd, &argc)
    94  	if e != nil {
    95  		return
    96  	}
    97  	defer syscall.LocalFree(syscall.Handle(uintptr(unsafe.Pointer(argv))))
    98  	Args = make([]string, argc)
    99  	for i, v := range (*argv)[:argc] {
   100  		Args[i] = string(syscall.UTF16ToString((*v)[:]))
   101  	}
   102  }
   103  
   104  func ftToDuration(ft *syscall.Filetime) time.Duration {
   105  	n := int64(ft.HighDateTime)<<32 + int64(ft.LowDateTime) // in 100-nanosecond intervals
   106  	return time.Duration(n*100) * time.Nanosecond
   107  }
   108  
   109  func (p *ProcessState) userTime() time.Duration {
   110  	return ftToDuration(&p.rusage.UserTime)
   111  }
   112  
   113  func (p *ProcessState) systemTime() time.Duration {
   114  	return ftToDuration(&p.rusage.KernelTime)
   115  }