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  	"internal/syscall/windows"
    10  	"runtime"
    11  	"sync/atomic"
    12  	"syscall"
    13  	"time"
    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  	defer p.Release()
    39  	return &ProcessState{p.Pid, syscall.WaitStatus{ExitCode: ec}, &u}, nil
    40  }
    41  
    42  func (p *Process) signal(sig Signal) error {
    43  	handle := atomic.LoadUintptr(&p.handle)
    44  	if handle == uintptr(syscall.InvalidHandle) {
    45  		return syscall.EINVAL
    46  	}
    47  	if p.done() {
    48  		return ErrProcessDone
    49  	}
    50  	if sig == Kill {
    51  		var terminationHandle syscall.Handle
    52  		e := syscall.DuplicateHandle(^syscall.Handle(0), syscall.Handle(handle), ^syscall.Handle(0), &terminationHandle, syscall.PROCESS_TERMINATE, false, 0)
    53  		if e != nil {
    54  			return NewSyscallError("DuplicateHandle", e)
    55  		}
    56  		runtime.KeepAlive(p)
    57  		defer syscall.CloseHandle(terminationHandle)
    58  		e = syscall.TerminateProcess(syscall.Handle(terminationHandle), 1)
    59  		return NewSyscallError("TerminateProcess", e)
    60  	}
    61  	// TODO(rsc): Handle Interrupt too?
    62  	return syscall.Errno(syscall.EWINDOWS)
    63  }
    64  
    65  func (p *Process) release() error {
    66  	handle := atomic.SwapUintptr(&p.handle, uintptr(syscall.InvalidHandle))
    67  	if handle == uintptr(syscall.InvalidHandle) {
    68  		return syscall.EINVAL
    69  	}
    70  	e := syscall.CloseHandle(syscall.Handle(handle))
    71  	if e != nil {
    72  		return NewSyscallError("CloseHandle", e)
    73  	}
    74  	// no need for a finalizer anymore
    75  	runtime.SetFinalizer(p, nil)
    76  	return nil
    77  }
    78  
    79  func findProcess(pid int) (p *Process, err error) {
    80  	const da = syscall.STANDARD_RIGHTS_READ |
    81  		syscall.PROCESS_QUERY_INFORMATION | syscall.SYNCHRONIZE
    82  	h, e := syscall.OpenProcess(da, false, uint32(pid))
    83  	if e != nil {
    84  		return nil, NewSyscallError("OpenProcess", e)
    85  	}
    86  	return newProcess(pid, uintptr(h)), nil
    87  }
    88  
    89  func init() {
    90  	cmd := windows.UTF16PtrToString(syscall.GetCommandLine())
    91  	if len(cmd) == 0 {
    92  		arg0, _ := Executable()
    93  		Args = []string{arg0}
    94  	} else {
    95  		Args = commandLineToArgv(cmd)
    96  	}
    97  }
    98  
    99  // appendBSBytes appends n '\\' bytes to b and returns the resulting slice.
   100  func appendBSBytes(b []byte, n int) []byte {
   101  	for ; n > 0; n-- {
   102  		b = append(b, '\\')
   103  	}
   104  	return b
   105  }
   106  
   107  // readNextArg splits command line string cmd into next
   108  // argument and command line remainder.
   109  func readNextArg(cmd string) (arg []byte, rest string) {
   110  	var b []byte
   111  	var inquote bool
   112  	var nslash int
   113  	for ; len(cmd) > 0; cmd = cmd[1:] {
   114  		c := cmd[0]
   115  		switch c {
   116  		case ' ', '\t':
   117  			if !inquote {
   118  				return appendBSBytes(b, nslash), cmd[1:]
   119  			}
   120  		case '"':
   121  			b = appendBSBytes(b, nslash/2)
   122  			if nslash%2 == 0 {
   123  				// use "Prior to 2008" rule from
   124  				// http://daviddeley.com/autohotkey/parameters/parameters.htm
   125  				// section 5.2 to deal with double double quotes
   126  				if inquote && len(cmd) > 1 && cmd[1] == '"' {
   127  					b = append(b, c)
   128  					cmd = cmd[1:]
   129  				}
   130  				inquote = !inquote
   131  			} else {
   132  				b = append(b, c)
   133  			}
   134  			nslash = 0
   135  			continue
   136  		case '\\':
   137  			nslash++
   138  			continue
   139  		}
   140  		b = appendBSBytes(b, nslash)
   141  		nslash = 0
   142  		b = append(b, c)
   143  	}
   144  	return appendBSBytes(b, nslash), ""
   145  }
   146  
   147  // commandLineToArgv splits a command line into individual argument
   148  // strings, following the Windows conventions documented
   149  // at http://daviddeley.com/autohotkey/parameters/parameters.htm#WINARGV
   150  func commandLineToArgv(cmd string) []string {
   151  	var args []string
   152  	for len(cmd) > 0 {
   153  		if cmd[0] == ' ' || cmd[0] == '\t' {
   154  			cmd = cmd[1:]
   155  			continue
   156  		}
   157  		var arg []byte
   158  		arg, cmd = readNextArg(cmd)
   159  		args = append(args, string(arg))
   160  	}
   161  	return args
   162  }
   163  
   164  func ftToDuration(ft *syscall.Filetime) time.Duration {
   165  	n := int64(ft.HighDateTime)<<32 + int64(ft.LowDateTime) // in 100-nanosecond intervals
   166  	return time.Duration(n*100) * time.Nanosecond
   167  }
   168  
   169  func (p *ProcessState) userTime() time.Duration {
   170  	return ftToDuration(&p.rusage.UserTime)
   171  }
   172  
   173  func (p *ProcessState) systemTime() time.Duration {
   174  	return ftToDuration(&p.rusage.KernelTime)
   175  }
   176
View as plain text