1 /*
   2  * Copyright (c) 2017, 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_JFR_CHECKPOINT_TYPES_JFRTYPESETWRITER_HPP
  26 #define SHARE_VM_JFR_CHECKPOINT_TYPES_JFRTYPESETWRITER_HPP
  27 
  28 #include "jfr/recorder/checkpoint/jfrCheckpointWriter.hpp"
  29 #include "jfr/utilities/jfrTypes.hpp"
  30 #include "memory/allocation.hpp"
  31 
  32 template <typename WriterImpl, u4 ID>
  33 class JfrArtifactWriterHost : public StackObj {
  34  private:
  35   WriterImpl _impl;
  36   JfrCheckpointWriter* _writer;
  37   JfrCheckpointContext _ctx;
  38   jlong _count_offset;
  39   int _count;
  40   bool _skip_header;
  41  public:
  42   JfrArtifactWriterHost(JfrCheckpointWriter* writer,
  43                         JfrArtifactSet* artifacts,
  44                         bool class_unload,
  45                         bool skip_header = false) : _impl(writer, artifacts, class_unload),
  46                                                     _writer(writer),
  47                                                     _ctx(writer->context()),
  48                                                     _count(0),
  49                                                     _skip_header(skip_header) {
  50     assert(_writer != NULL, "invariant");
  51     if (!_skip_header) {
  52       _writer->write_type((JfrTypeId)ID);
  53       _count_offset = _writer->reserve(sizeof(u4)); // Don't know how many yet
  54     }
  55   }
  56 
  57   ~JfrArtifactWriterHost() {
  58     if (_count == 0) {
  59       // nothing written, restore context for rewind
  60       _writer->set_context(_ctx);
  61       return;
  62     }
  63     assert(_count > 0, "invariant");
  64     if (!_skip_header) {
  65       _writer->write_count(_count, _count_offset);
  66     }
  67   }
  68 
  69   bool operator()(typename WriterImpl::Type const & value) {
  70     this->_count += _impl(value);
  71     return true;
  72   }
  73 
  74   int count() const   { return _count; }
  75   void add(int count) { _count += count; }
  76 };
  77 
  78 typedef int(*artifact_write_operation)(JfrCheckpointWriter*, JfrArtifactSet*, const void*);
  79 
  80 template <typename T, artifact_write_operation op>
  81 class JfrArtifactWriterImplHost {
  82  private:
  83   JfrCheckpointWriter* _writer;
  84   JfrArtifactSet* _artifacts;
  85   bool _class_unload;
  86  public:
  87   typedef T Type;
  88   JfrArtifactWriterImplHost(JfrCheckpointWriter* writer, JfrArtifactSet* artifacts, bool class_unload) :
  89     _writer(writer), _artifacts(artifacts), _class_unload(class_unload) {}
  90   int operator()(T const& value) {
  91     return op(this->_writer, this->_artifacts, value);
  92   }
  93 };
  94 
  95 template <typename T, typename Predicate, artifact_write_operation op>
  96 class JfrPredicatedArtifactWriterImplHost : public JfrArtifactWriterImplHost<T, op> {
  97  private:
  98   Predicate _predicate;
  99   typedef JfrArtifactWriterImplHost<T, op> Parent;
 100  public:
 101   JfrPredicatedArtifactWriterImplHost(JfrCheckpointWriter* writer, JfrArtifactSet* artifacts, bool class_unload) :
 102     Parent(writer, artifacts, class_unload), _predicate(class_unload) {}
 103   int operator()(T const& value) {
 104     return _predicate(value) ? Parent::operator()(value) : 0;
 105   }
 106 };
 107 
 108 #endif // SHARE_VM_JFR_CHECKPOINT_TYPES_JFRTYPESETWRITER_HPP