1 /*
   2  * Copyright (c) 2016, 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.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  */
  23 
  24 package jdk.tools.jaotc.jnilibelf;
  25 
  26 import jdk.internal.misc.Unsafe;
  27 
  28 import static jdk.tools.jaotc.jnilibelf.UnsafeAccess.UNSAFE;
  29 
  30 public class Pointer {
  31 
  32     private final long address;
  33 
  34     public Pointer(long val) {
  35         address = val;
  36     }
  37 
  38     /**
  39      * Put (i.e., copy) content of byte array at consecutive addresses beginning at this Pointer.
  40      *
  41      * @param src source byte array
  42      */
  43     public void put(byte[] src) {
  44         UNSAFE.copyMemory(src, Unsafe.ARRAY_BYTE_BASE_OFFSET, null, address, src.length);
  45     }
  46 
  47     /**
  48      * Get (i.e., copy) content at this Pointer to the given byte array.
  49      *
  50      * @param dst destination byte array
  51      */
  52     public void get(byte[] dst) {
  53         UNSAFE.copyMemory(null, address, dst, Unsafe.ARRAY_BYTE_BASE_OFFSET, dst.length);
  54     }
  55 
  56     /**
  57      * Read {@code readSize} number of bytes to copy them starting at {@code startIndex} of
  58      * {@code byteArray}
  59      *
  60      * @param byteArray target array to copy bytes
  61      * @param readSize number of bytes to copy
  62      * @param startIndex index of the array to start copy at
  63      */
  64     public void copyBytesTo(byte[] byteArray, int readSize, int startIndex) {
  65         long end = (long)startIndex + (long)readSize;
  66         if (end > byteArray.length) {
  67             throw new IllegalArgumentException("writing beyond array bounds");
  68         }
  69         UNSAFE.copyMemory(null, address, byteArray, Unsafe.ARRAY_BYTE_BASE_OFFSET+startIndex, readSize);
  70     }
  71 
  72 }