...
Run Format

Source file src/os/exec_windows.go

Documentation: os

     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.
    42  	// See https://golang.org/issue/25965 for details.
    43  	defer time.Sleep(5 * time.Millisecond)
    44  	defer p.Release()
    45  	return &ProcessState{p.Pid, syscall.WaitStatus{ExitCode: ec}, &u}, nil
    46  }
    47  
    48  func terminateProcess(pid, exitcode int) error {
    49  	h, e := syscall.OpenProcess(syscall.PROCESS_TERMINATE, false, uint32(pid))
    50  	if e != nil {
    51  		return NewSyscallError("OpenProcess", e)
    52  	}
    53  	defer syscall.CloseHandle(h)
    54  	e = syscall.TerminateProcess(h, uint32(exitcode))
    55  	return NewSyscallError("TerminateProcess", e)
    56  }
    57  
    58  func (p *Process) signal(sig Signal) error {
    59  	handle := atomic.LoadUintptr(&p.handle)
    60  	if handle == uintptr(syscall.InvalidHandle) {
    61  		return syscall.EINVAL
    62  	}
    63  	if p.done() {
    64  		return errors.New("os: process already finished")
    65  	}
    66  	if sig == Kill {
    67  		err := terminateProcess(p.Pid, 1)
    68  		runtime.KeepAlive(p)
    69  		return err
    70  	}
    71  	// TODO(rsc): Handle Interrupt too?
    72  	return syscall.Errno(syscall.EWINDOWS)
    73  }
    74  
    75  func (p *Process) release() error {
    76  	handle := atomic.LoadUintptr(&p.handle)
    77  	if handle == uintptr(syscall.InvalidHandle) {
    78  		return syscall.EINVAL
    79  	}
    80  	e := syscall.CloseHandle(syscall.Handle(handle))
    81  	if e != nil {
    82  		return NewSyscallError("CloseHandle", e)
    83  	}
    84  	atomic.StoreUintptr(&p.handle, uintptr(syscall.InvalidHandle))
    85  	// no need for a finalizer anymore
    86  	runtime.SetFinalizer(p, nil)
    87  	return nil
    88  }
    89  
    90  func findProcess(pid int) (p *Process, err error) {
    91  	const da = syscall.STANDARD_RIGHTS_READ |
    92  		syscall.PROCESS_QUERY_INFORMATION | syscall.SYNCHRONIZE
    93  	h, e := syscall.OpenProcess(da, false, uint32(pid))
    94  	if e != nil {
    95  		return nil, NewSyscallError("OpenProcess", e)
    96  	}
    97  	return newProcess(pid, uintptr(h)), nil
    98  }
    99  
   100  func init() {
   101  	p := syscall.GetCommandLine()
   102  	cmd := syscall.UTF16ToString((*[0xffff]uint16)(unsafe.Pointer(p))[:])
   103  	if len(cmd) == 0 {
   104  		arg0, _ := Executable()
   105  		Args = []string{arg0}
   106  	} else {
   107  		Args = commandLineToArgv(cmd)
   108  	}
   109  }
   110  
   111  // appendBSBytes appends n '\\' bytes to b and returns the resulting slice.
   112  func appendBSBytes(b []byte, n int) []byte {
   113  	for ; n > 0; n-- {
   114  		b = append(b, '\\')
   115  	}
   116  	return b
   117  }
   118  
   119  // readNextArg splits command line string cmd into next
   120  // argument and command line remainder.
   121  func readNextArg(cmd string) (arg []byte, rest string) {
   122  	var b []byte
   123  	var inquote bool
   124  	var nslash int
   125  	for ; len(cmd) > 0; cmd = cmd[1:] {
   126  		c := cmd[0]
   127  		switch c {
   128  		case ' ', '\t':
   129  			if !inquote {
   130  				return appendBSBytes(b, nslash), cmd[1:]
   131  			}
   132  		case '"':
   133  			b = appendBSBytes(b, nslash/2)
   134  			if nslash%2 == 0 {
   135  				// use "Prior to 2008" rule from
   136  				// http://daviddeley.com/autohotkey/parameters/parameters.htm
   137  				// section 5.2 to deal with double double quotes
   138  				if inquote && len(cmd) > 1 && cmd[1] == '"' {
   139  					b = append(b, c)
   140  					cmd = cmd[1:]
   141  				}
   142  				inquote = !inquote
   143  			} else {
   144  				b = append(b, c)
   145  			}
   146  			nslash = 0
   147  			continue
   148  		case '\\':
   149  			nslash++
   150  			continue
   151  		}
   152  		b = appendBSBytes(b, nslash)
   153  		nslash = 0
   154  		b = append(b, c)
   155  	}
   156  	return appendBSBytes(b, nslash), ""
   157  }
   158  
   159  // commandLineToArgv splits a command line into individual argument
   160  // strings, following the Windows conventions documented
   161  // at http://daviddeley.com/autohotkey/parameters/parameters.htm#WINARGV
   162  func commandLineToArgv(cmd string) []string {
   163  	var args []string
   164  	for len(cmd) > 0 {
   165  		if cmd[0] == ' ' || cmd[0] == '\t' {
   166  			cmd = cmd[1:]
   167  			continue
   168  		}
   169  		var arg []byte
   170  		arg, cmd = readNextArg(cmd)
   171  		args = append(args, string(arg))
   172  	}
   173  	return args
   174  }
   175  
   176  func ftToDuration(ft *syscall.Filetime) time.Duration {
   177  	n := int64(ft.HighDateTime)<<32 + int64(ft.LowDateTime) // in 100-nanosecond intervals
   178  	return time.Duration(n*100) * time.Nanosecond
   179  }
   180  
   181  func (p *ProcessState) userTime() time.Duration {
   182  	return ftToDuration(&p.rusage.UserTime)
   183  }
   184  
   185  func (p *ProcessState) systemTime() time.Duration {
   186  	return ftToDuration(&p.rusage.KernelTime)
   187  }
   188  

View as plain text