1 /*
   2  * Copyright (c) 2015, 2018, 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 
  25 #ifndef SHARE_VM_RUNTIME_FLAGS_JVMFLAGWRITEABLE_HPP
  26 #define SHARE_VM_RUNTIME_FLAGS_JVMFLAGWRITEABLE_HPP
  27 
  28 #include "runtime/flags/jvmFlag.hpp"
  29 #include "utilities/growableArray.hpp"
  30 
  31 class JVMFlagWriteable : public CHeapObj<mtArguments> {
  32 public:
  33   enum WriteableType {
  34     // can be set without any limits
  35     Always           = 0,
  36     // can only be set once, either via command lines or during runtime
  37     Once             = 1,
  38     // can only be set on command line (multiple times allowed)
  39     CommandLineOnly  = 2
  40   };
  41 private:
  42   const char* _name;
  43   WriteableType _type;
  44   bool _writeable;
  45   bool _startup_done;
  46 public:
  47   // the "name" argument must be a string literal
  48   JVMFlagWriteable(const char* name, WriteableType type) { _name=name; _type=type; _writeable=true; _startup_done=false; }
  49   ~JVMFlagWriteable() {}
  50   const char* name() { return _name; }
  51   const WriteableType type() { return _type; }
  52   bool is_writeable(void);
  53   void mark_once(void);
  54   void mark_startup(void);
  55 };
  56 
  57 class JVMFlagWriteableList : public AllStatic {
  58   static GrowableArray<JVMFlagWriteable*>* _controls;
  59 public:
  60   static void init();
  61   static int length() { return (_controls != NULL) ? _controls->length() : 0; }
  62   static JVMFlagWriteable* at(int i) { return (_controls != NULL) ? _controls->at(i) : NULL; }
  63   static JVMFlagWriteable* find(const char* name);
  64   static void add(JVMFlagWriteable* range) { _controls->append(range); }
  65   static void mark_startup(void);
  66 };
  67 
  68 #endif // SHARE_VM_RUNTIME_FLAGS_JVMFLAGWRITEABLE_HPP