func lck(fd, from, ln int) (err error) {
fmt.Printf("lck:%v %v %v\n", fd, from, ln)
fmt.Println(os.Getpid())
// ol := windows.Overlapped{Offset: uint32(from), OffsetHigh: uint32(from >> 32), HEvent: windows.Handle(0)}
// r1, _, err := procLockFileEx.Call(uintptr(fd), uintptr(LOCKFILE_EXCLUSIVE_LOCK | LOCKFILE_FAIL_IMMEDIATELY), uintptr(0), uintptr(int32(ln)), uintptr(int32(ln >> 32)), uintptr(unsafe.Pointer(&ol)))
// if r1 != 1 {
// return err
// }
// return nil
lk := unix.Flock_t{Type: unix.F_WRLCK, Whence: int16(os.SEEK_SET), Start: int64(from), Len: int64(ln)}
//return unix.FcntlFlock(uintptr(fd), unix.F_SETLKW, &lk)
r1, _, errno := unix.Syscall(unix.SYS_FCNTL, uintptr(fd), uintptr(unix.F_GETFL), uintptr(unsafe.Pointer(&lk)))
fmt.Printf("\tlck_test:%v %v %v\n", r1, lk, errno)
lk = unix.Flock_t{Type: unix.F_WRLCK, Whence: int16(os.SEEK_SET), Start: int64(from), Len: int64(ln)}
r1, _, errno = unix.Syscall(unix.SYS_FCNTL, uintptr(fd), uintptr(unix.F_SETLK), uintptr(unsafe.Pointer(&lk)))
fmt.Printf("\tlck:%v %v %v\n", r1, lk, errno)
if errno == 0 {
return nil
}
err = errno
return err
}
// In environments where svlogd is used, the pipe that becomes STDIN of this
// program can be non-blocking. Go's File implementation does not play well
// with non-blocking pipes, in particular it does not recover from an EAGAIN
// error from read(2).
// This function defensively sets its 0th file descriptor to be blocking so
// that we do not have to handle EAGAIN errors.
func setSTDINToBlock() error {
oldflags, _, errno := unix.Syscall(unix.SYS_FCNTL, 0, unix.F_GETFL, 0)
if errno != 0 {
return fmt.Errorf("unix.FCNTL F_GETFL errno: %d", errno)
}
_, _, errno = unix.Syscall(unix.SYS_FCNTL, 0, unix.F_SETFL, oldflags&^unix.O_NONBLOCK)
if errno != 0 {
return fmt.Errorf("unix.FCNTL F_SETFL errno: %d", errno)
}
return nil
}
func ioCtl(fd *os.File) (bufLen int, err error) {
bufLen = 1
_, _, errno := unix.Syscall(unix.SYS_IOCTL, fd.Fd(), uintptr(unix.BIOCIMMEDIATE), uintptr(unsafe.Pointer(&bufLen)))
if errno != 0 {
err = errno
return
}
_, _, errno = unix.Syscall(unix.SYS_IOCTL, fd.Fd(), uintptr(unix.BIOCGBLEN), uintptr(unsafe.Pointer(&bufLen)))
if errno != 0 {
err = errno
}
return
}
func JailAttach(jid int) error {
if _, _, err := unix.Syscall(unix.SYS_JAIL_ATTACH, uintptr(jid), 0, 0); err == 0 {
return nil
} else {
return err
}
}
// GetWinsize gets the winsize struct with the terminal size set by the kernel.
func GetWinsize(fd int, ws *Winsize) (err error) {
_, _, e1 := unix.Syscall(unix.SYS_IOCTL, uintptr(fd),
uintptr(TIOCGWINSZ), uintptr(unsafe.Pointer(ws)))
if e1 != 0 {
err = e1
}
return
}
func Getattr(fd int, state *Termios) (err error) {
_, _, e1 := unix.Syscall(unix.SYS_IOCTL, uintptr(fd),
uintptr(TCGETS), uintptr(unsafe.Pointer(state)))
if e1 != 0 {
err = e1
}
return
}
func setns(fd int) error {
ret, _, err := unix.Syscall(SYS_SETNS, uintptr(uint(fd)), uintptr(CLONE_NEWNS), 0)
if ret != 0 {
return fmt.Errorf("syscall SYS_SETNS failed: %v", err)
}
return nil
}
func insert(fd uintptr, s string) error {
for _, c := range s {
ptr := uintptr(unsafe.Pointer(&c))
if _, _, e := unix.Syscall(unix.SYS_IOCTL, fd, unix.TIOCSTI, ptr); e != 0 {
return fmt.Errorf("syscall errno: %d\n", e)
}
}
return nil
}
func getwinsize() winsize {
ws := winsize{}
_, _, err := unix.Syscall(syscall.SYS_IOCTL,
uintptr(0), uintptr(syscall.TIOCGWINSZ),
uintptr(unsafe.Pointer(&ws)))
if err != 0 {
log.Fatalf("TIOCGWINSZ failed to get terminal size: %s\n", err)
}
return ws
}
func (ns *netNS) Set() error {
if err := ns.errorIfClosed(); err != nil {
return err
}
if _, _, err := unix.Syscall(unix.SYS_SETNS, ns.Fd(), uintptr(unix.CLONE_NEWNET), 0); err != 0 {
return fmt.Errorf("Error switching to ns %v: %v", ns.file.Name(), err)
}
return nil
}
// Mprotect calls mprotect(2) on the mmapped region.
func (m Map) Mprotect(prot Perms) (err error) {
_, _, e1 := unix.Syscall(
unix.SYS_MPROTECT,
uintptr(m.Start),
uintptr(m.End-m.Start),
uintptr(prot),
)
if e1 != 0 {
return e1
}
return
}
func rlck(fd, from, ln int) (err error) {
// ol := windows.Overlapped{Offset: uint32(from), OffsetHigh: uint32(from >> 32), HEvent: windows.Handle(0)}
// r1, _, err := procLockFileEx.Call(uintptr(fd), uintptr(LOCKFILE_FAIL_IMMEDIATELY), uintptr(0), uintptr(int32(ln)), uintptr(int32(ln >> 32)), uintptr(unsafe.Pointer(&ol)))
// if r1 != 1 {
// return err
// }
// return nil
// type Flock_t struct {
// Type int16
// Whence int16
// Pad_cgo_0 [4]byte
// Start int64
// Len int64
// Pid int32
// Pad_cgo_1 [4]byte
// }
// FcntlFlock performs a fcntl syscall for the F_GETLK, F_SETLK or F_SETLKW command.
// func FcntlFlock(fd uintptr, cmd int, lk *Flock_t) error {
// _, _, errno := Syscall(fcntl64Syscall, fd, uintptr(cmd), uintptr(unsafe.Pointer(lk)))
// if errno == 0 {
// return nil
// }
// return errno
// }
fmt.Printf("rlck:%v %v %v\n", fd, from, ln)
fmt.Println(os.Getpid())
lk := unix.Flock_t{Type: unix.F_RDLCK, Whence: int16(os.SEEK_SET), Start: int64(from), Len: int64(ln)}
r1, _, errno := unix.Syscall(unix.SYS_FCNTL, uintptr(fd), uintptr(unix.F_GETFL), uintptr(unsafe.Pointer(&lk)))
fmt.Printf("\trlck_test:%v %v %v\n", r1, lk, errno)
lk = unix.Flock_t{Type: unix.F_RDLCK, Whence: int16(os.SEEK_SET), Start: int64(from), Len: int64(ln)}
r1, _, errno = unix.Syscall(unix.SYS_FCNTL, uintptr(fd), uintptr(unix.F_SETLK), uintptr(unsafe.Pointer(&lk)))
fmt.Printf("\trlck:%v %v %v\n", r1, lk, errno)
if errno == 0 {
return nil
}
err = errno
return err
}
func ifReq(fd *os.File, ifName string) (err error) {
req := struct {
Name [0x10]byte
pad [0x28 - 0x10]byte
}{}
copy(req.Name[:], ifName)
_, _, errno := unix.Syscall(unix.SYS_IOCTL, fd.Fd(), uintptr(unix.BIOCSETIF), uintptr(unsafe.Pointer(&req)))
if errno != 0 {
err = errno
return err
}
return
}
func main() {
flag.Parse()
l := uintptr(3)
if *clearSyslog {
l = 4
}
b := make([]byte, 256*1024)
if amt, _, err := unix.Syscall(unix.SYS_SYSLOG, l, uintptr(unsafe.Pointer(&b[0])), uintptr(len(b))); err == 0 {
os.Stdout.Write(b[:amt])
} else {
log.Fatalf("syslog failed: %v", err)
}
}
func (m *Mixer) writeVolume(channelVolume int) error {
_, _, err := unix.Syscall(
unix.SYS_IOCTL,
m.device.Fd(),
SOUND_MIXER_WRITE_VOLUME,
uintptr(unsafe.Pointer(&channelVolume)),
)
if err != 0 {
return err
}
return nil
}
// Call msync(2) with the MS_SYNC flag on a slice previously returned by
// mmap(2).
func msync(p []byte) (err error) {
_, _, errno := unix.Syscall(
unix.SYS_MSYNC,
uintptr(unsafe.Pointer(&p[0])),
uintptr(len(p)),
unix.MS_SYNC)
if errno != 0 {
err = errno
return
}
return
}
// mmap the given file, get the mincore vector, then
// return it as an []bool
func FileMincore(f *os.File, size int64) ([]bool, error) {
//skip could not mmap error when the file size is 0
if int(size) == 0 {
return nil, nil
}
// mmap is a []byte
mmap, err := unix.Mmap(int(f.Fd()), 0, int(size), unix.PROT_NONE, unix.MAP_SHARED)
if err != nil {
return nil, fmt.Errorf("could not mmap: %v", err)
}
// TODO: check for MAP_FAILED which is ((void *) -1)
// but maybe unnecessary since it looks like errno is always set when MAP_FAILED
// one byte per page, only LSB is used, remainder is reserved and clear
vecsz := (size + int64(os.Getpagesize()) - 1) / int64(os.Getpagesize())
vec := make([]byte, vecsz)
// get all of the arguments to the mincore syscall converted to uintptr
mmap_ptr := uintptr(unsafe.Pointer(&mmap[0]))
size_ptr := uintptr(size)
vec_ptr := uintptr(unsafe.Pointer(&vec[0]))
// use Go's ASM to submit directly to the kernel, no C wrapper needed
// mincore(2): int mincore(void *addr, size_t length, unsigned char *vec);
// 0 on success, takes the pointer to the mmap, a size, which is the
// size that came from f.Stat(), and the vector, which is a pointer
// to the memory behind an []byte
// this writes a snapshot of the data into vec which a list of 8-bit flags
// with the LSB set if the page in that position is currently in VFS cache
ret, _, err := unix.Syscall(unix.SYS_MINCORE, mmap_ptr, size_ptr, vec_ptr)
if ret != 0 {
return nil, fmt.Errorf("syscall SYS_MINCORE failed: %v", err)
}
defer unix.Munmap(mmap)
mc := make([]bool, vecsz)
// there is no bitshift only bool
for i, b := range vec {
if b%2 == 1 {
mc[i] = true
} else {
mc[i] = false
}
}
return mc, nil
}
func MakeNetworkNS(containerID string) string {
namespace := "/var/run/netns/" + containerID
err := os.MkdirAll("/var/run/netns", 0600)
Expect(err).NotTo(HaveOccurred())
// create an empty file at the mount point
mountPointFd, err := os.Create(namespace)
Expect(err).NotTo(HaveOccurred())
mountPointFd.Close()
var wg sync.WaitGroup
wg.Add(1)
// do namespace work in a dedicated goroutine, so that we can safely
// Lock/Unlock OSThread without upsetting the lock/unlock state of
// the caller of this function. See block comment above.
go (func() {
defer wg.Done()
runtime.LockOSThread()
defer runtime.UnlockOSThread()
defer GinkgoRecover()
// capture current thread's original netns
currentThreadNetNSPath := getCurrentThreadNetNSPath()
originalNetNS, err := unix.Open(currentThreadNetNSPath, unix.O_RDONLY, 0)
Expect(err).NotTo(HaveOccurred())
defer unix.Close(originalNetNS)
// create a new netns on the current thread
err = unix.Unshare(unix.CLONE_NEWNET)
Expect(err).NotTo(HaveOccurred())
// bind mount the new netns from the current thread onto the mount point
err = unix.Mount(currentThreadNetNSPath, namespace, "none", unix.MS_BIND, "")
Expect(err).NotTo(HaveOccurred())
// reset current thread's netns to the original
_, _, e1 := unix.Syscall(unix.SYS_SETNS, uintptr(originalNetNS), uintptr(unix.CLONE_NEWNET), 0)
Expect(e1).To(BeZero())
})()
wg.Wait()
return namespace
}
func (m *Mixer) readVolume() (int, error) {
var currentVolume int
_, _, err := unix.Syscall(
unix.SYS_IOCTL,
m.device.Fd(),
SOUND_MIXER_READ_VOLUME,
uintptr(unsafe.Pointer(¤tVolume)),
)
if err != 0 {
return 0, err
}
return currentVolume & 0xff, nil
}
func Setattr(fd int, action uint, state *Termios) (err error) {
switch action {
case TCSANOW:
action = TCSETS
case TCSADRAIN:
action = TCSETSW
case TCSAFLUSH:
action = TCSETSF
}
_, _, e1 := unix.Syscall(unix.SYS_IOCTL, uintptr(fd),
uintptr(action), uintptr(unsafe.Pointer(state)))
if e1 != 0 {
err = e1
}
return
}
func unlck(fd, from, ln int) (err error) {
fmt.Printf("unlck:%v %v %v\n", fd, from, ln)
// ol := windows.Overlapped{Offset: uint32(from), OffsetHigh: uint32(from >> 32), HEvent: windows.Handle(0)}
// r1, _, err := procUnlockFileEx.Call(uintptr(fd), uintptr(0), uintptr(int32(ln)), uintptr(int32(ln >> 32)), uintptr(unsafe.Pointer(&ol)))
// if r1 != 1 {
// return err
// }
// return nil//windows.CloseHandle(windows.Handle(fd))
lk := unix.Flock_t{Type: unix.F_UNLCK, Whence: int16(os.SEEK_SET), Start: int64(from), Len: int64(ln)}
//return unix.FcntlFlock(uintptr(fd), unix.F_SETLKW, &lk)
r1, _, errno := unix.Syscall(unix.SYS_FCNTL, uintptr(fd), uintptr(unix.F_SETLK), uintptr(unsafe.Pointer(&lk)))
fmt.Printf("\tunlck:%v %v %v\n", r1, lk, errno)
if errno == 0 {
return nil
}
err = errno
return err
}
func removexattr(path string, attr string) (err error) {
var _p0 *byte
_p0, err = unix.BytePtrFromString(path)
if err != nil {
return
}
var _p1 *byte
_p1, err = unix.BytePtrFromString(attr)
if err != nil {
return
}
_, _, e1 := unix.Syscall(unix.SYS_REMOVEXATTR, uintptr(unsafe.Pointer(_p0)), uintptr(unsafe.Pointer(_p1)), 0)
use(unsafe.Pointer(_p0))
use(unsafe.Pointer(_p1))
if e1 != 0 {
err = syscall.Errno(e1)
}
return
}
func makeNetworkNS(containerID string) string {
namespace := "/var/run/netns/" + containerID
pid := unix.Getpid()
tid := unix.Gettid()
err := os.MkdirAll("/var/run/netns", 0600)
Expect(err).NotTo(HaveOccurred())
runtime.LockOSThread()
defer runtime.UnlockOSThread()
go (func() {
defer GinkgoRecover()
err = unix.Unshare(unix.CLONE_NEWNET)
Expect(err).NotTo(HaveOccurred())
fd, err := os.Create(namespace)
Expect(err).NotTo(HaveOccurred())
defer fd.Close()
err = unix.Mount("/proc/self/ns/net", namespace, "none", unix.MS_BIND, "")
Expect(err).NotTo(HaveOccurred())
})()
Eventually(namespace).Should(BeAnExistingFile())
fd, err := unix.Open(fmt.Sprintf("/proc/%d/task/%d/ns/net", pid, tid), unix.O_RDONLY, 0)
Expect(err).NotTo(HaveOccurred())
defer unix.Close(fd)
_, _, e1 := unix.Syscall(unix.SYS_SETNS, uintptr(fd), uintptr(unix.CLONE_NEWNET), 0)
Expect(e1).To(BeZero())
return namespace
}
func ioctl(f *os.File, req int, ptr unsafe.Pointer) syscall.Errno {
_, _, err := unix.Syscall(unix.SYS_IOCTL, uintptr(f.Fd()), uintptr(req), uintptr(ptr))
return err
}
func ioctl(fd, op, arg uintptr) error {
if _, _, ep := unix.Syscall(unix.SYS_IOCTL, fd, op, arg); ep != 0 {
return ep
}
return nil
}
