1 /*
   2  * Copyright (c) 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.
   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_LOGGING_LOGSTREAM_HPP
  26 #define SHARE_VM_LOGGING_LOGSTREAM_HPP
  27 
  28 #include "logging/log.hpp"
  29 #include "logging/logHandle.hpp"
  30 #include "memory/resourceArea.hpp"
  31 #include "utilities/ostream.hpp"
  32 
  33 
  34 class LogStream : public outputStream {
  35   bufferedStream  _current_line;
  36   LogTargetHandle _log_handle;
  37 
  38 public:
  39   // Constructor to support creation from a LogTarget instance.
  40   //
  41   // LogTarget(Debug, gc) log;
  42   // LogStreamBase(log) stream;
  43   template <LogLevelType level, LogTagType T0, LogTagType T1, LogTagType T2, LogTagType T3, LogTagType T4, LogTagType GuardTag>
  44   LogStream(const LogTargetImpl<level, T0, T1, T2, T3, T4, GuardTag>& type_carrier) :
  45       _log_handle(level, &LogTagSetMapping<T0, T1, T2, T3, T4>::tagset()) {}
  46 
  47   // Constructor to support creation from typed (likely NULL) pointer. Mostly used by the logging framework.
  48   //
  49   // LogStreamBase stream(log.debug());
  50   //  or
  51   // LogStreamBase stream((LogTargetImpl<level, T0, T1, T2, T3, T4, GuardTag>*)NULL);
  52   template <LogLevelType level, LogTagType T0, LogTagType T1, LogTagType T2, LogTagType T3, LogTagType T4, LogTagType GuardTag>
  53   LogStream(const LogTargetImpl<level, T0, T1, T2, T3, T4, GuardTag>* type_carrier) :
  54       _log_handle(level, &LogTagSetMapping<T0, T1, T2, T3, T4>::tagset()) {}
  55 
  56   // Constructor to support creation from a LogTargetHandle.
  57   //
  58   // LogTarget(Debug, gc) log;
  59   // LogTargetHandle(log) handle;
  60   // LogStreamBase stream(handle);
  61   LogStream(LogTargetHandle handle) : _log_handle(handle) {}
  62 
  63   // Constructor to support creation from a log level and tagset.
  64   //
  65   // LogStreamBase(level, tageset);
  66   LogStream(LogLevelType level, LogTagSet* tagset) : _log_handle(level, tagset) {}
  67 
  68   ~LogStream() {
  69     guarantee(_current_line.size() == 0, "Buffer not flushed. Missing call to print_cr()?");
  70   }
  71 
  72 public:
  73   void write(const char* s, size_t len);
  74 };
  75 
  76 typedef LogStream LogStreamNoResourceMark;
  77 typedef LogStream LogStreamCHeap;
  78 
  79 // Support creation of a LogStream without having to provide a LogTarget pointer.
  80 #define LogStreamHandle(level, ...) LogStreamTemplate<LogLevel::level, LOG_TAGS(__VA_ARGS__)>
  81 
  82 template <LogLevelType level, LogTagType T0, LogTagType T1, LogTagType T2, LogTagType T3, LogTagType T4, LogTagType GuardTag>
  83 class LogStreamTemplate : public LogStream {
  84 public:
  85   LogStreamTemplate() : LogStream((LogTargetImpl<level, T0, T1, T2, T3, T4, GuardTag>*)NULL) {}
  86 };
  87 
  88 
  89 #endif // SHARE_VM_LOGGING_LOGSTREAM_HPP