/*
* Copyright (c) 2008, 2015, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
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*/
package sun.font;
import java.io.File;
import java.io.OutputStream;
import java.security.AccessController;
import java.security.PrivilegedAction;
import java.util.HashMap;
import java.util.Map;
import java.util.concurrent.Semaphore;
import java.util.concurrent.TimeUnit;
import sun.awt.AppContext;
import sun.awt.util.ThreadGroupUtils;
public class CreatedFontTracker {
public static final int MAX_FILE_SIZE = 32 * 1024 * 1024;
public static final int MAX_TOTAL_BYTES = 10 * MAX_FILE_SIZE;
static CreatedFontTracker tracker;
int numBytes;
public static synchronized CreatedFontTracker getTracker() {
if (tracker == null) {
tracker = new CreatedFontTracker();
}
return tracker;
}
private CreatedFontTracker() {
numBytes = 0;
}
public synchronized int getNumBytes() {
return numBytes;
}
public synchronized void addBytes(int sz) {
numBytes += sz;
}
public synchronized void subBytes(int sz) {
numBytes -= sz;
}
/**
* Returns an AppContext-specific counting semaphore.
*/
private static synchronized Semaphore getCS() {
final AppContext appContext = AppContext.getAppContext();
Semaphore cs = (Semaphore) appContext.get(CreatedFontTracker.class);
if (cs == null) {
// Make a semaphore with 5 permits that obeys the first-in first-out
// granting of permits.
cs = new Semaphore(5, true);
appContext.put(CreatedFontTracker.class, cs);
}
return cs;
}
public boolean acquirePermit() throws InterruptedException {
// This does a timed-out wait.
return getCS().tryAcquire(120, TimeUnit.SECONDS);
}
public void releasePermit() {
getCS().release();
}
public void add(File file) {
TempFileDeletionHook.add(file);
}
public void set(File file, OutputStream os) {
TempFileDeletionHook.set(file, os);
}
public void remove(File file) {
TempFileDeletionHook.remove(file);
}
/**
* Helper class for cleanup of temp files created while processing fonts.
* Note that this only applies to createFont() from an InputStream object.
*/
private static class TempFileDeletionHook {
private static HashMap<File, OutputStream> files = new HashMap<>();
private static Thread t = null;
static void init() {
if (t == null) {
// Add a shutdown hook to remove the temp file.
AccessController.doPrivileged((PrivilegedAction<Void>) () -> {
/* The thread must be a member of a thread group
* which will not get GCed before VM exit.
* Make its parent the top-level thread group.
*/
ThreadGroup rootTG = ThreadGroupUtils.getRootThreadGroup();
t = new Thread(rootTG, TempFileDeletionHook::runHooks,
"TempFontFileDeleter", 0, false);
/* Set context class loader to null in order to avoid
* keeping a strong reference to an application classloader.
*/
t.setContextClassLoader(null);
Runtime.getRuntime().addShutdownHook(t);
return null;
});
}
}
private TempFileDeletionHook() {}
static synchronized void add(File file) {
init();
files.put(file, null);
}
static synchronized void set(File file, OutputStream os) {
files.put(file, os);
}
static synchronized void remove(File file) {
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