1 /*
   2  * Copyright (c) 2015, 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 #ifndef SHARE_VM_LOGGING_LOGFILEOUTPUT_HPP
  25 #define SHARE_VM_LOGGING_LOGFILEOUTPUT_HPP
  26 
  27 #include "logging/logFileStreamOutput.hpp"
  28 #include "runtime/semaphore.hpp"
  29 #include "utilities/globalDefinitions.hpp"
  30 
  31 class LogDecorations;
  32 
  33 // The log file output, with support for file rotation based on a target size.
  34 class LogFileOutput : public LogFileStreamOutput {
  35  private:
  36   static const char*  FileOpenMode;
  37   static const char*  FileCountOptionKey;
  38   static const char*  FileSizeOptionKey;
  39   static const char*  PidFilenamePlaceholder;
  40   static const char*  TimestampFilenamePlaceholder;
  41   static const char*  TimestampFormat;
  42   static const size_t DefaultFileCount = 5;
  43   static const size_t DefaultFileSize = 20 * M;
  44   static const size_t StartTimeBufferSize = 20;
  45   static const size_t PidBufferSize = 21;
  46   static const uint   MaxRotationFileCount = 1000;
  47   static char         _pid_str[PidBufferSize];
  48   static char         _vm_start_time_str[StartTimeBufferSize];
  49 
  50   const char* _name;
  51   char* _file_name;
  52   char* _archive_name;
  53 
  54   uint  _current_file;
  55   uint  _file_count;
  56   uint  _file_count_max_digits;
  57 
  58   size_t  _archive_name_len;
  59   size_t  _rotate_size;
  60   size_t  _current_size;
  61 
  62   // Semaphore used for synchronizing file rotations and writes
  63   Semaphore _rotation_semaphore;
  64 
  65   void archive();
  66   void rotate();
  67   bool parse_options(const char* options, outputStream* errstream);
  68   char *make_file_name(const char* file_name, const char* pid_string, const char* timestamp_string);
  69 
  70   bool should_rotate() {
  71     return _file_count > 0 && _rotate_size > 0 && _current_size >= _rotate_size;
  72   }
  73 
  74   void increment_file_count() {
  75     _current_file++;
  76     if (_current_file == _file_count) {
  77       _current_file = 0;
  78     }
  79   }
  80 
  81  public:
  82   LogFileOutput(const char *name);
  83   virtual ~LogFileOutput();
  84   virtual bool initialize(const char* options, outputStream* errstream);
  85   virtual int write(const LogDecorations& decorations, const char* msg);
  86   virtual int write(LogMessageBuffer::Iterator msg_iterator);
  87   virtual void force_rotate();
  88   virtual void describe(outputStream *out);
  89 
  90   virtual const char* name() const {
  91     return _name;
  92   }
  93 
  94   static const char* Prefix;
  95   static void set_file_name_parameters(jlong start_time);
  96 };
  97 
  98 #endif // SHARE_VM_LOGGING_LOGFILEOUTPUT_HPP