1 /*
   2  * Copyright (c) 2012, 2019, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.  Oracle designates this
   8  * particular file as subject to the "Classpath" exception as provided
   9  * by Oracle in the LICENSE file that accompanied this code.
  10  *
  11  * This code is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * version 2 for more details (a copy is included in the LICENSE file that
  15  * accompanied this code).
  16  *
  17  * You should have received a copy of the GNU General Public License version
  18  * 2 along with this work; if not, write to the Free Software Foundation,
  19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
  21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  22  * or visit www.oracle.com if you need additional information or have any
  23  * questions.
  24  */
  25 
  26 package jdk.jfr.internal.jfc;
  27 
  28 import java.io.CharArrayReader;
  29 import java.io.CharArrayWriter;
  30 import java.io.IOException;
  31 import java.io.Reader;
  32 import java.text.ParseException;
  33 import jdk.internal.org.xml.sax.InputSource;
  34 import jdk.internal.org.xml.sax.SAXException;
  35 import jdk.internal.util.xml.SAXParser;
  36 import jdk.internal.util.xml.impl.SAXParserImpl;
  37 import jdk.jfr.Configuration;
  38 
  39 import jdk.jfr.internal.PrivateAccess;
  40 
  41 /**
  42  * Parses a JDK Flight Recorder Configuration file (.jfc)
  43  */
  44 final class JFCParser {
  45     static final String FILE_EXTENSION = ".jfc";
  46     private static final int MAXIMUM_FILE_SIZE = 1024 * 1024;
  47 
  48     public static Configuration createConfiguration(String name, Reader reader) throws IOException, ParseException {
  49         return createConfiguration(name, readContent(reader));
  50     }
  51 
  52     public static Configuration createConfiguration(String name, String content) throws IOException, ParseException {
  53         try {
  54             JFCParserHandler ch = new JFCParserHandler();
  55             parseXML(content, ch);
  56             return PrivateAccess.getInstance().newConfiguration(name, ch.label, ch.description, ch.provider, ch.settings, content);
  57         } catch (IllegalArgumentException iae) {
  58             throw new ParseException(iae.getMessage(), -1);
  59         } catch (SAXException e) {
  60             ParseException pe =  new ParseException("Error reading JFC file. " + e.getMessage(), -1);
  61             pe.initCause(e);
  62             throw pe;
  63         }
  64     }
  65 
  66     private static void parseXML(String content, JFCParserHandler ch) throws SAXException, IOException {
  67         CharArrayReader r = new CharArrayReader(content.toCharArray());
  68         SAXParser parser = new SAXParserImpl();
  69         parser.parse(new InputSource(r), ch);
  70     }
  71 
  72     private static String readContent(Reader r) throws IOException {
  73         CharArrayWriter writer = new CharArrayWriter(1024);
  74         int count = 0;
  75         int ch;
  76         while ((ch = r.read()) != -1) {
  77             writer.write(ch);
  78             count++;
  79             if (count >= MAXIMUM_FILE_SIZE) {
  80                 throw new IOException("Presets with more than " + MAXIMUM_FILE_SIZE + " characters can't be read.");
  81             }
  82         }
  83         return new String(writer.toCharArray());
  84     }
  85 }