1 /*
   2  * Copyright (c) 2012, 2020, 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
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  24 #ifndef SHARE_JFR_RECORDER_REPOSITORY_JFRREPOSITORY_HPP
  25 #define SHARE_JFR_RECORDER_REPOSITORY_JFRREPOSITORY_HPP
  26 
  27 #include "jni.h"
  28 #include "jfr/utilities/jfrAllocation.hpp"
  29 
  30 class JfrChunkWriter;
  31 class JfrPostBox;
  32 
  33 //
  34 // Represents the location on disk where internal files, "chunks", are stored.
  35 //
  36 // A "chunk" is a self-contained file artifact storing events and metadata that
  37 // has been moved out of process memory.
  38 //
  39 // Chunk files are associated with recordings and are managed at a higher level in Java.
  40 // Java continously keeps the VM informed about new chunk locations via set_chunk_path().
  41 //
  42 // A JfrChunkWriter will open the next chunk file which it maintains as the current chunk.
  43 // There is a rotation scheme in place for creating new chunks at certain intervals.
  44 //
  45 class JfrRepository : public JfrCHeapObj {
  46   friend class JfrRecorder;
  47   friend class JfrRecorderService;
  48  private:
  49   char* _path;
  50   JfrPostBox& _post_box;
  51 
  52   JfrRepository(JfrPostBox& post_box);
  53   ~JfrRepository();
  54 
  55   bool set_path(const char* path);
  56   void set_chunk_path(const char* path);
  57   bool open_chunk(bool vm_error = false);
  58   size_t close_chunk();
  59   size_t flush_chunk();
  60   void on_vm_error();
  61 
  62   static void notify_on_new_chunk_path();
  63   static JfrChunkWriter& chunkwriter();
  64 
  65   static JfrRepository& instance();
  66   static JfrRepository* create(JfrPostBox& post_box);
  67   bool initialize();
  68   static void destroy();
  69 
  70  public:
  71   static void set_path(jstring location, JavaThread* jt);
  72   static void set_chunk_path(jstring path, JavaThread* jt);
  73   static void mark_chunk_final();
  74   static void flush(JavaThread* jt);
  75   static jlong current_chunk_start_nanos();
  76   static void on_vm_error_report(outputStream* st);
  77 };
  78 
  79 #endif // SHARE_JFR_RECORDER_REPOSITORY_JFRREPOSITORY_HPP