1/*
2 * Copyright (c) 2016, 2019, 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.
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23 */
24
25#ifndef SHARE_LOGGING_LOGSTREAM_HPP
26#define SHARE_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
34class LogStream : public outputStream {
35 friend class LogStreamTest_TestLineBufferAllocation_test_vm_Test; // see test/native/logging/test_logStream.cpp
36 friend class LogStreamTest_TestLineBufferAllocationCap_test_vm_Test; // see test/native/logging/test_logStream.cpp
37
38 // Helper class, maintains the line buffer. For small line lengths,
39 // we avoid malloc and use a fixed sized member char array. If LogStream
40 // is allocated on the stack, this means small lines are assembled
41 // directly on the stack.
42 class LineBuffer {
43 char _smallbuf[64];
44 char* _buf;
45 size_t _cap;
46 size_t _pos;
47 void try_ensure_cap(size_t cap);
48 public:
49 LineBuffer();
50 ~LineBuffer();
51 bool is_empty() const { return _pos == 0; }
52 const char* buffer() const { return _buf; }
53 void append(const char* s, size_t len);
54 void reset();
55 };
56 LineBuffer _current_line;
57 LogTargetHandle _log_handle;
58
59 // Prevent operator new for LogStream.
60 static void* operator new (size_t);
61 static void* operator new[] (size_t);
62
63public:
64 // Constructor to support creation from a LogTarget instance.
65 //
66 // LogTarget(Debug, gc) log;
67 // LogStreamBase(log) stream;
68 template <LogLevelType level, LogTagType T0, LogTagType T1, LogTagType T2, LogTagType T3, LogTagType T4, LogTagType GuardTag>
69 LogStream(const LogTargetImpl<level, T0, T1, T2, T3, T4, GuardTag>& type_carrier) :
70 _log_handle(level, &LogTagSetMapping<T0, T1, T2, T3, T4>::tagset()) {}
71
72 // Constructor to support creation from typed (likely NULL) pointer. Mostly used by the logging framework.
73 //
74 // LogStreamBase stream(log.debug());
75 // or
76 // LogStreamBase stream((LogTargetImpl<level, T0, T1, T2, T3, T4, GuardTag>*)NULL);
77 template <LogLevelType level, LogTagType T0, LogTagType T1, LogTagType T2, LogTagType T3, LogTagType T4, LogTagType GuardTag>
78 LogStream(const LogTargetImpl<level, T0, T1, T2, T3, T4, GuardTag>* type_carrier) :
79 _log_handle(level, &LogTagSetMapping<T0, T1, T2, T3, T4>::tagset()) {}
80
81 // Destructor writes any unfinished output left in the line buffer.
82 ~LogStream();
83
84 // Constructor to support creation from a LogTargetHandle.
85 //
86 // LogTarget(Debug, gc) log;
87 // LogTargetHandle(log) handle;
88 // LogStreamBase stream(handle);
89 LogStream(LogTargetHandle handle) : _log_handle(handle) {}
90
91 // Constructor to support creation from a log level and tagset.
92 //
93 // LogStreamBase(level, tageset);
94 LogStream(LogLevelType level, LogTagSet* tagset) : _log_handle(level, tagset) {}
95
96 void write(const char* s, size_t len);
97};
98
99// Support creation of a LogStream without having to provide a LogTarget pointer.
100#define LogStreamHandle(level, ...) LogStreamTemplate<LogLevel::level, LOG_TAGS(__VA_ARGS__)>
101
102template <LogLevelType level, LogTagType T0, LogTagType T1, LogTagType T2, LogTagType T3, LogTagType T4, LogTagType GuardTag>
103class LogStreamTemplate : public LogStream {
104public:
105 LogStreamTemplate() : LogStream((LogTargetImpl<level, T0, T1, T2, T3, T4, GuardTag>*)NULL) {}
106};
107
108#endif // SHARE_LOGGING_LOGSTREAM_HPP
109