func getUnitFileName() (unit string, err error) {
libname := C.CString("libsystemd.so")
defer C.free(unsafe.Pointer(libname))
handle := C.dlopen(libname, C.RTLD_LAZY)
if handle == nil {
err = fmt.Errorf("error opening libsystemd.so")
return
}
defer func() {
if r := C.dlclose(handle); r != 0 {
err = fmt.Errorf("error closing libsystemd.so")
}
}()
sym := C.CString("sd_pid_get_unit")
defer C.free(unsafe.Pointer(sym))
sd_pid_get_unit := C.dlsym(handle, sym)
if sd_pid_get_unit == nil {
err = fmt.Errorf("error resolving sd_pid_get_unit function")
return
}
var s string
u := C.CString(s)
defer C.free(unsafe.Pointer(u))
ret := C.my_sd_pid_get_unit(sd_pid_get_unit, 0, &u)
if ret < 0 {
err = fmt.Errorf("error calling sd_pid_get_unit: %v", syscall.Errno(-ret))
return
}
unit = C.GoString(u)
return
}
func Close(handle uintptr) error {
ret := C.dlclose(unsafe.Pointer(handle))
if ret != 0 {
return errors.New(C.GoString(C.dlerror()))
}
return nil
}
func getSlice() (slice string, err error) {
libname := C.CString("libsystemd.so")
defer C.free(unsafe.Pointer(libname))
handle := C.dlopen(libname, C.RTLD_LAZY)
if handle == nil {
err = fmt.Errorf("error opening libsystemd.so")
return
}
defer func() {
if r := C.dlclose(handle); r != 0 {
err = fmt.Errorf("error closing libsystemd.so")
}
}()
sym := C.CString("sd_pid_get_slice")
defer C.free(unsafe.Pointer(sym))
sd_pid_get_slice := C.dlsym(handle, sym)
if sd_pid_get_slice == nil {
err = fmt.Errorf("error resolving sd_pid_get_slice function")
return
}
var s string
sl := C.CString(s)
defer C.free(unsafe.Pointer(sl))
ret := C.my_sd_pid_get_slice(sd_pid_get_slice, 0, &sl)
if ret < 0 {
err = fmt.Errorf("error calling sd_pid_get_slice: %v", syscall.Errno(-ret))
return
}
slice = C.GoString(sl)
return
}
func (h Handle) Close() error {
o := C.dlclose(h.c)
if o != C.int(0) {
c_err := C.dlerror()
return fmt.Errorf("dl: %s", C.GoString(c_err))
}
return nil
}
func (h *libHandle) close() error {
C.dlerror()
C.dlclose(h.handle)
e := C.dlerror()
if e != nil {
return errwrap.Wrap(fmt.Errorf("error closing %v", h.libname), errors.New(C.GoString(e)))
}
return nil
}
// Close closes a LibHandle.
func (l *LibHandle) Close() error {
C.dlerror()
C.dlclose(l.Handle)
e := C.dlerror()
if e != nil {
return fmt.Errorf("error closing %v: %v", l.Libname, errors.New(C.GoString(e)))
}
return nil
}
func dlclose(handle uintptr) error {
Chandle := unsafe.Pointer(handle)
errno, _ := C.dlclose(Chandle)
if errno != 0 {
CErrString, _ := C.dlerror()
return errors.New(C.GoString(CErrString))
} else {
return nil
}
}
func dlclose(lib unsafe.Pointer) (err error) {
dlmtx.Lock()
defer dlmtx.Unlock()
if C.dlclose(lib) != 0 {
err = dlerror()
}
return
}
func (library *Library) Close() int {
if library == nil {
return -1
}
if library.ptr == nil {
return -1
}
res := C.dlclose(library.ptr)
library.ptr = nil
return int(res)
}
func loadThySelf(t *testing.T, symbol string) {
this_process := C.dlopen(nil, C.RTLD_NOW)
if this_process == nil {
t.Fatal("dlopen:", C.GoString(C.dlerror()))
}
defer C.dlclose(this_process)
symbol_address := C.dlsym(this_process, C.CString(symbol))
if symbol_address == nil {
t.Fatal("dlsym:", C.GoString(C.dlerror()))
} else {
t.Log(symbol, symbol_address)
}
}
/*
* loadThySelf()
* Go doesn't support dynamic linking. However, it supports a C interface that supports
* dynamic linking. And it supports symbol export allowing callbacks into go functions
* using a C calling convention. So, Go supports dynamic linking.
*/
func loadThySelf(symbol string) *[0]byte {
this_process := C.dlopen(nil, C.RTLD_NOW)
if this_process == nil {
panic(C.GoString(C.dlerror()))
}
symbol_address := C.dlsym(this_process, C.CString(symbol))
if symbol_address == nil {
panic(C.GoString(C.dlerror()))
}
C.dlclose(this_process)
return (*[0]byte)(unsafe.Pointer(symbol_address))
}
// Close closes the shared library handle. All symbols
// loaded from the library will become invalid.
func (d *DL) Close() error {
if d.handle != nil {
d.mu.Lock()
defer d.mu.Unlock()
if d.handle != nil {
mu.Lock()
defer mu.Unlock()
if C.dlclose(d.handle) != 0 {
return dlerror()
}
d.handle = nil
}
}
return nil
}
// Unload closes the handle to the dynamically-linked gssapi library.
func (lib *Lib) Unload() error {
if lib == nil || lib.handle == nil {
return nil
}
runtime.LockOSThread()
defer runtime.UnlockOSThread()
i := C.dlclose(lib.handle)
if i == -1 {
return fmt.Errorf("%s", C.GoString(C.dlerror()))
}
lib.handle = nil
return nil
}
func loadThySelf(t *testing.T, symbol string) {
this_process := C.dlopen(nil, C.RTLD_NOW)
if this_process == nil {
t.Error("dlopen:", C.GoString(C.dlerror()))
return
}
defer C.dlclose(this_process)
symbol_address := C.dlsym(this_process, C.CString(symbol))
if symbol_address == nil {
t.Error("dlsym:", C.GoString(C.dlerror()))
return
}
t.Log(symbol, symbol_address)
C.call4029(symbol_address)
}
func isRunningFromUnitFile() (ret bool, err error) {
libname := C.CString("libsystemd.so")
defer C.free(unsafe.Pointer(libname))
handle := C.dlopen(libname, C.RTLD_LAZY)
if handle == nil {
// we can't open libsystemd.so so we assume systemd is not
// installed and we're not running from a unit file
ret = false
return
}
defer func() {
if r := C.dlclose(handle); r != 0 {
err = fmt.Errorf("error closing libsystemd.so")
}
}()
sd_pid_get_owner_uid := C.dlsym(handle, C.CString("sd_pid_get_owner_uid"))
if sd_pid_get_owner_uid == nil {
err = fmt.Errorf("error resolving sd_pid_get_owner_uid function")
return
}
var uid C.uid_t
errno := C.my_sd_pid_get_owner_uid(sd_pid_get_owner_uid, 0, &uid)
// when we're running from a unit file, sd_pid_get_owner_uid returns
// ENOENT (systemd <220) or ENXIO (systemd >=220)
switch {
case errno >= 0:
ret = false
return
case syscall.Errno(-errno) == syscall.ENOENT || syscall.Errno(-errno) == syscall.ENXIO:
ret = true
return
default:
err = fmt.Errorf("error calling sd_pid_get_owner_uid: %v", syscall.Errno(-errno))
return
}
}
func dlclose(p uintptr) {
C.dlclose(unsafe.Pointer(p))
}
//TODO(t): add error handling
func Release(handle unsafe.Pointer) int {
return int(C.dlclose(handle))
}
func (h *libHandle) Close() error {
if r := C.dlclose(h.handle); r != 0 {
return fmt.Errorf("error closing %v: %d", h.libname, r)
}
return nil
}
