static UserPrincipal fromSid(long sidAddress) throws IOException {
String sidString;
try {
sidString = ConvertSidToStringSid(sidAddress);
if (sidString == null) {
// pre-Windows XP system?
throw new AssertionError();
}
} catch (WindowsException x) {
throw new IOException("Unable to convert SID to String: " + x.errorString());
}
// lookup account; if not available then use the SID as the name
Account account = null;
String name;
try {
account = LookupAccountSid(sidAddress);
name = account.domain() + "\\" + account.name();
} catch (WindowsException x) {
name = sidString;
}
int sidType = (account == null) ? SidTypeUnknown : account.use();
if ((sidType == SidTypeGroup)
|| (sidType == SidTypeWellKnownGroup)
|| (sidType == SidTypeAlias)) // alias for local group
{
return new Group(sidString, sidType, name);
} else {
return new User(sidString, sidType, name);
}
}
static UserPrincipal lookup(String name) throws IOException {
SecurityManager sm = System.getSecurityManager();
if (sm != null) {
sm.checkPermission(new RuntimePermission("lookupUserInformation"));
}
// invoke LookupAccountName to get buffer size needed for SID
int size = 0;
try {
size = LookupAccountName(name, 0L, 0);
} catch (WindowsException x) {
if (x.lastError() == ERROR_NONE_MAPPED) throw new UserPrincipalNotFoundException(name);
throw new IOException(name + ": " + x.errorString());
}
assert size > 0;
// allocate buffer and re-invoke LookupAccountName get SID
NativeBuffer sidBuffer = NativeBuffers.getNativeBuffer(size);
try {
int newSize = LookupAccountName(name, sidBuffer.address(), size);
if (newSize != size) {
// can this happen?
throw new AssertionError("SID change during lookup");
}
// return user principal
return fromSid(sidBuffer.address());
} catch (WindowsException x) {
throw new IOException(name + ": " + x.errorString());
} finally {
sidBuffer.release();
}
}
@Override
void wakeup() throws IOException {
try {
PostQueuedCompletionStatus(port, WAKEUP_COMPLETION_KEY);
} catch (WindowsException x) {
throw new IOException(x.getMessage());
}
}
/** Creates an I/O completion port and a daemon thread to service it */
WindowsWatchService(WindowsFileSystem fs) throws IOException {
// create I/O completion port
long port = 0L;
try {
port = CreateIoCompletionPort(INVALID_HANDLE_VALUE, 0, 0);
} catch (WindowsException x) {
throw new IOException(x.getMessage());
}
this.poller = new Poller(fs, this, port);
this.poller.start();
}
/**
* Open/creates file, returning AsynchronousFileChannel to access the file
*
* @param pathForWindows The path of the file to open/create
* @param pathToCheck The path used for permission checks (if security manager)
* @param pool The thread pool that the channel is associated with
*/
static AsynchronousFileChannel newAsynchronousFileChannel(
String pathForWindows,
String pathToCheck,
Set<? extends OpenOption> options,
long pSecurityDescriptor,
ThreadPool pool)
throws IOException {
Flags flags = Flags.toFlags(options);
// Overlapped I/O required
flags.overlapped = true;
// default is reading
if (!flags.read && !flags.write) {
flags.read = true;
}
// validation
if (flags.append) throw new UnsupportedOperationException("APPEND not allowed");
// open file for overlapped I/O
FileDescriptor fdObj;
try {
fdObj = open(pathForWindows, pathToCheck, flags, pSecurityDescriptor);
} catch (WindowsException x) {
x.rethrowAsIOException(pathForWindows);
return null;
}
// create the AsynchronousFileChannel
try {
return WindowsAsynchronousFileChannelImpl.open(fdObj, flags.read, flags.write, pool);
} catch (IOException x) {
// IOException is thrown if the file handle cannot be associated
// with the completion port. All we can do is close the file.
long handle = fdAccess.getHandle(fdObj);
CloseHandle(handle);
throw x;
}
}
/** Poller main loop */
@Override
public void run() {
for (; ; ) {
CompletionStatus info;
try {
info = GetQueuedCompletionStatus(port);
} catch (WindowsException x) {
// this should not happen
x.printStackTrace();
return;
}
// wakeup
if (info.completionKey() == WAKEUP_COMPLETION_KEY) {
boolean shutdown = processRequests();
if (shutdown) {
return;
}
continue;
}
// map completionKey to get WatchKey
WindowsWatchKey key = ck2key.get((int) info.completionKey());
if (key == null) {
// We get here when a registration is changed. In that case
// the directory is closed which causes an event with the
// old completion key.
continue;
}
boolean criticalError = false;
int errorCode = info.error();
int messageSize = info.bytesTransferred();
if (errorCode == ERROR_NOTIFY_ENUM_DIR) {
// buffer overflow
key.signalEvent(StandardWatchEventKinds.OVERFLOW, null);
} else if (errorCode != 0 && errorCode != ERROR_MORE_DATA) {
// ReadDirectoryChangesW failed
criticalError = true;
} else {
// ERROR_MORE_DATA is a warning about incomplete
// data transfer over TCP/UDP stack. For the case
// [messageSize] is zero in the most of cases.
if (messageSize > 0) {
// process non-empty events.
processEvents(key, messageSize);
} else if (errorCode == 0) {
// insufficient buffer size
// not described, but can happen.
key.signalEvent(StandardWatchEventKinds.OVERFLOW, null);
}
// start read for next batch of changes
try {
ReadDirectoryChangesW(
key.handle(),
key.buffer().address(),
CHANGES_BUFFER_SIZE,
key.watchSubtree(),
ALL_FILE_NOTIFY_EVENTS,
key.countAddress(),
key.overlappedAddress());
} catch (WindowsException x) {
// no choice but to cancel key
criticalError = true;
}
}
if (criticalError) {
implCancelKey(key);
key.signal();
}
}
}
/**
* Register a directory for changes as follows:
*
* <p>1. Open directory 2. Read its attributes (and check it really is a directory) 3. Assign
* completion key and associated handle with completion port 4. Call ReadDirectoryChangesW to
* start (async) read of changes 5. Create or return existing key representing registration
*/
@Override
Object implRegister(
Path obj, Set<? extends WatchEvent.Kind<?>> events, WatchEvent.Modifier... modifiers) {
WindowsPath dir = (WindowsPath) obj;
boolean watchSubtree = false;
// FILE_TREE modifier allowed
for (WatchEvent.Modifier modifier : modifiers) {
if (modifier == ExtendedWatchEventModifier.FILE_TREE) {
watchSubtree = true;
} else {
if (modifier == null) return new NullPointerException();
if (modifier instanceof com.sun.nio.file.SensitivityWatchEventModifier)
continue; // ignore
return new UnsupportedOperationException("Modifier not supported");
}
}
// open directory
long handle;
try {
handle =
CreateFile(
dir.getPathForWin32Calls(),
FILE_LIST_DIRECTORY,
(FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE),
OPEN_EXISTING,
FILE_FLAG_BACKUP_SEMANTICS | FILE_FLAG_OVERLAPPED);
} catch (WindowsException x) {
return x.asIOException(dir);
}
boolean registered = false;
try {
// read attributes and check file is a directory
WindowsFileAttributes attrs;
try {
attrs = WindowsFileAttributes.readAttributes(handle);
} catch (WindowsException x) {
return x.asIOException(dir);
}
if (!attrs.isDirectory()) {
return new NotDirectoryException(dir.getPathForExceptionMessage());
}
// check if this directory is already registered
FileKey fk =
new FileKey(attrs.volSerialNumber(), attrs.fileIndexHigh(), attrs.fileIndexLow());
WindowsWatchKey existing = fk2key.get(fk);
// if already registered and we're not changing the subtree
// modifier then simply update the event and return the key.
if (existing != null && watchSubtree == existing.watchSubtree()) {
existing.setEvents(events);
return existing;
}
// Can overflow the int type capacity.
// Skip WAKEUP_COMPLETION_KEY value.
int completionKey = ++lastCompletionKey;
if (completionKey == WAKEUP_COMPLETION_KEY) completionKey = ++lastCompletionKey;
// associate handle with completion port
try {
CreateIoCompletionPort(handle, port, completionKey);
} catch (WindowsException x) {
return new IOException(x.getMessage());
}
// allocate memory for events, including space for other structures
// needed to do overlapped I/O
int size = CHANGES_BUFFER_SIZE + SIZEOF_DWORD + SIZEOF_OVERLAPPED;
NativeBuffer buffer = NativeBuffers.getNativeBuffer(size);
long bufferAddress = buffer.address();
long overlappedAddress = bufferAddress + size - SIZEOF_OVERLAPPED;
long countAddress = overlappedAddress - SIZEOF_DWORD;
// zero the overlapped structure
UNSAFE.setMemory(overlappedAddress, SIZEOF_OVERLAPPED, (byte) 0);
// start async read of changes to directory
try {
createAndAttachEvent(overlappedAddress);
ReadDirectoryChangesW(
handle,
bufferAddress,
CHANGES_BUFFER_SIZE,
watchSubtree,
ALL_FILE_NOTIFY_EVENTS,
countAddress,
overlappedAddress);
} catch (WindowsException x) {
closeAttachedEvent(overlappedAddress);
buffer.release();
return new IOException(x.getMessage());
}
WindowsWatchKey watchKey;
if (existing == null) {
// not registered so create new watch key
watchKey =
new WindowsWatchKey(dir, watcher, fk)
.init(
handle,
events,
watchSubtree,
buffer,
countAddress,
overlappedAddress,
completionKey);
// map file key to watch key
fk2key.put(fk, watchKey);
} else {
// directory already registered so need to:
// 1. remove mapping from old completion key to existing watch key
// 2. release existing key's resources (handle/buffer)
// 3. re-initialize key with new handle/buffer
ck2key.remove(existing.completionKey());
releaseResources(existing);
watchKey =
existing.init(
handle,
events,
watchSubtree,
buffer,
countAddress,
overlappedAddress,
completionKey);
}
// map completion map to watch key
ck2key.put(completionKey, watchKey);
registered = true;
return watchKey;
} finally {
if (!registered) CloseHandle(handle);
}
}