open-nomad/vendor/github.com/mitchellh/go-ps/process_windows.go
Diptanu Choudhury 74e3cb804b Vendoring go-ps
2016-05-28 19:51:22 -07:00

120 lines
2.4 KiB
Go

// +build windows
package ps
import (
"fmt"
"syscall"
"unsafe"
)
// Windows API functions
var (
modKernel32 = syscall.NewLazyDLL("kernel32.dll")
procCloseHandle = modKernel32.NewProc("CloseHandle")
procCreateToolhelp32Snapshot = modKernel32.NewProc("CreateToolhelp32Snapshot")
procProcess32First = modKernel32.NewProc("Process32FirstW")
procProcess32Next = modKernel32.NewProc("Process32NextW")
)
// Some constants from the Windows API
const (
ERROR_NO_MORE_FILES = 0x12
MAX_PATH = 260
)
// PROCESSENTRY32 is the Windows API structure that contains a process's
// information.
type PROCESSENTRY32 struct {
Size uint32
CntUsage uint32
ProcessID uint32
DefaultHeapID uintptr
ModuleID uint32
CntThreads uint32
ParentProcessID uint32
PriorityClassBase int32
Flags uint32
ExeFile [MAX_PATH]uint16
}
// WindowsProcess is an implementation of Process for Windows.
type WindowsProcess struct {
pid int
ppid int
exe string
}
func (p *WindowsProcess) Pid() int {
return p.pid
}
func (p *WindowsProcess) PPid() int {
return p.ppid
}
func (p *WindowsProcess) Executable() string {
return p.exe
}
func newWindowsProcess(e *PROCESSENTRY32) *WindowsProcess {
// Find when the string ends for decoding
end := 0
for {
if e.ExeFile[end] == 0 {
break
}
end++
}
return &WindowsProcess{
pid: int(e.ProcessID),
ppid: int(e.ParentProcessID),
exe: syscall.UTF16ToString(e.ExeFile[:end]),
}
}
func findProcess(pid int) (Process, error) {
ps, err := processes()
if err != nil {
return nil, err
}
for _, p := range ps {
if p.Pid() == pid {
return p, nil
}
}
return nil, nil
}
func processes() ([]Process, error) {
handle, _, _ := procCreateToolhelp32Snapshot.Call(
0x00000002,
0)
if handle < 0 {
return nil, syscall.GetLastError()
}
defer procCloseHandle.Call(handle)
var entry PROCESSENTRY32
entry.Size = uint32(unsafe.Sizeof(entry))
ret, _, _ := procProcess32First.Call(handle, uintptr(unsafe.Pointer(&entry)))
if ret == 0 {
return nil, fmt.Errorf("Error retrieving process info.")
}
results := make([]Process, 0, 50)
for {
results = append(results, newWindowsProcess(&entry))
ret, _, _ := procProcess32Next.Call(handle, uintptr(unsafe.Pointer(&entry)))
if ret == 0 {
break
}
}
return results, nil
}