github.com/rakyll/go@v0.0.0-20170216000551-64c02460d703/src/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  	"sync/atomic"
    11  	"syscall"
    12  	"time"
    13  	"unsafe"
    14  )
    15  
    16  func (p *Process) wait() (ps *ProcessState, err error) {
    17  	handle := atomic.LoadUintptr(&p.handle)
    18  	s, e := syscall.WaitForSingleObject(syscall.Handle(handle), syscall.INFINITE)
    19  	switch s {
    20  	case syscall.WAIT_OBJECT_0:
    21  		break
    22  	case syscall.WAIT_FAILED:
    23  		return nil, NewSyscallError("WaitForSingleObject", e)
    24  	default:
    25  		return nil, errors.New("os: unexpected result from WaitForSingleObject")
    26  	}
    27  	var ec uint32
    28  	e = syscall.GetExitCodeProcess(syscall.Handle(handle), &ec)
    29  	if e != nil {
    30  		return nil, NewSyscallError("GetExitCodeProcess", e)
    31  	}
    32  	var u syscall.Rusage
    33  	e = syscall.GetProcessTimes(syscall.Handle(handle), &u.CreationTime, &u.ExitTime, &u.KernelTime, &u.UserTime)
    34  	if e != nil {
    35  		return nil, NewSyscallError("GetProcessTimes", e)
    36  	}
    37  	p.setDone()
    38  	// NOTE(brainman): It seems that sometimes process is not dead
    39  	// when WaitForSingleObject returns. But we do not know any
    40  	// other way to wait for it. Sleeping for a while seems to do
    41  	// the trick sometimes. So we will sleep and smell the roses.
    42  	defer time.Sleep(5 * time.Millisecond)
    43  	defer p.Release()
    44  	return &ProcessState{p.Pid, syscall.WaitStatus{ExitCode: ec}, &u}, nil
    45  }
    46  
    47  func terminateProcess(pid, exitcode int) error {
    48  	h, e := syscall.OpenProcess(syscall.PROCESS_TERMINATE, false, uint32(pid))
    49  	if e != nil {
    50  		return NewSyscallError("OpenProcess", e)
    51  	}
    52  	defer syscall.CloseHandle(h)
    53  	e = syscall.TerminateProcess(h, uint32(exitcode))
    54  	return NewSyscallError("TerminateProcess", e)
    55  }
    56  
    57  func (p *Process) signal(sig Signal) error {
    58  	handle := atomic.LoadUintptr(&p.handle)
    59  	if handle == uintptr(syscall.InvalidHandle) {
    60  		return syscall.EINVAL
    61  	}
    62  	if p.done() {
    63  		return errors.New("os: process already finished")
    64  	}
    65  	if sig == Kill {
    66  		err := terminateProcess(p.Pid, 1)
    67  		runtime.KeepAlive(p)
    68  		return err
    69  	}
    70  	// TODO(rsc): Handle Interrupt too?
    71  	return syscall.Errno(syscall.EWINDOWS)
    72  }
    73  
    74  func (p *Process) release() error {
    75  	handle := atomic.LoadUintptr(&p.handle)
    76  	if handle == uintptr(syscall.InvalidHandle) {
    77  		return syscall.EINVAL
    78  	}
    79  	e := syscall.CloseHandle(syscall.Handle(handle))
    80  	if e != nil {
    81  		return NewSyscallError("CloseHandle", e)
    82  	}
    83  	atomic.StoreUintptr(&p.handle, uintptr(syscall.InvalidHandle))
    84  	// no need for a finalizer anymore
    85  	runtime.SetFinalizer(p, nil)
    86  	return nil
    87  }
    88  
    89  func findProcess(pid int) (p *Process, err error) {
    90  	const da = syscall.STANDARD_RIGHTS_READ |
    91  		syscall.PROCESS_QUERY_INFORMATION | syscall.SYNCHRONIZE
    92  	h, e := syscall.OpenProcess(da, false, uint32(pid))
    93  	if e != nil {
    94  		return nil, NewSyscallError("OpenProcess", e)
    95  	}
    96  	return newProcess(pid, uintptr(h)), nil
    97  }
    98  
    99  func init() {
   100  	var argc int32
   101  	cmd := syscall.GetCommandLine()
   102  	argv, e := syscall.CommandLineToArgv(cmd, &argc)
   103  	if e != nil {
   104  		return
   105  	}
   106  	defer syscall.LocalFree(syscall.Handle(uintptr(unsafe.Pointer(argv))))
   107  	Args = make([]string, argc)
   108  	for i, v := range (*argv)[:argc] {
   109  		Args[i] = syscall.UTF16ToString((*v)[:])
   110  	}
   111  }
   112  
   113  func ftToDuration(ft *syscall.Filetime) time.Duration {
   114  	n := int64(ft.HighDateTime)<<32 + int64(ft.LowDateTime) // in 100-nanosecond intervals
   115  	return time.Duration(n*100) * time.Nanosecond
   116  }
   117  
   118  func (p *ProcessState) userTime() time.Duration {
   119  	return ftToDuration(&p.rusage.UserTime)
   120  }
   121  
   122  func (p *ProcessState) systemTime() time.Duration {
   123  	return ftToDuration(&p.rusage.KernelTime)
   124  }