1 /*
   2  * Copyright (c) 2007, 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.  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 sun.java2d.marlin;
  27 
  28 import static sun.java2d.marlin.MarlinConst.LOG_UNSAFE_MALLOC;
  29 import jdk.internal.misc.Unsafe;
  30 import jdk.internal.ref.CleanerFactory;
  31 
  32 /**
  33  *
  34  * @author bourgesl
  35  */
  36 final class OffHeapArray  {
  37 
  38     // unsafe reference
  39     static final Unsafe UNSAFE;
  40     // size of int / float
  41     static final int SIZE_INT;
  42 
  43     static {
  44         UNSAFE   = Unsafe.getUnsafe();
  45         SIZE_INT = Unsafe.ARRAY_INT_INDEX_SCALE;
  46     }
  47 
  48     /* members */
  49     long address;
  50     long length;
  51     int  used;
  52 
  53     OffHeapArray(final Object parent, final long len) {
  54         // note: may throw OOME:
  55         this.address = UNSAFE.allocateMemory(len);
  56         this.length  = len;
  57         this.used    = 0;
  58         if (LOG_UNSAFE_MALLOC) {
  59             MarlinUtils.logInfo(System.currentTimeMillis()
  60                                 + ": OffHeapArray.allocateMemory =   "
  61                                 + len + " to addr = " + this.address);
  62         }
  63 
  64         // Register a cleaning function to ensure freeing off-heap memory:
  65         CleanerFactory.cleaner().register(parent, () -> this.free());
  66     }
  67 
  68     /*
  69      * As realloc may change the address, updating address is MANDATORY
  70      * @param len new array length
  71      * @throws OutOfMemoryError if the allocation is refused by the system
  72      */
  73     void resize(final long len) {
  74         // note: may throw OOME:
  75         this.address = UNSAFE.reallocateMemory(address, len);
  76         this.length  = len;
  77         if (LOG_UNSAFE_MALLOC) {
  78             MarlinUtils.logInfo(System.currentTimeMillis()
  79                                 + ": OffHeapArray.reallocateMemory = "
  80                                 + len + " to addr = " + this.address);
  81         }
  82     }
  83 
  84     void free() {
  85         UNSAFE.freeMemory(this.address);
  86         if (LOG_UNSAFE_MALLOC) {
  87             MarlinUtils.logInfo(System.currentTimeMillis()
  88                                 + ": OffHeapArray.freeMemory =       "
  89                                 + this.length
  90                                 + " at addr = " + this.address);
  91         }
  92     }
  93 
  94     void fill(final byte val) {
  95         UNSAFE.setMemory(this.address, this.length, val);
  96     }
  97 }