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 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 const char* ptr() const { return _buf; } 52 void append(const char* s, size_t len); 53 void reset(); 54 }; 55 LineBuffer _current_line; 56 LogTargetHandle _log_handle; 57 58 // Prevent operator new for LogStream. 59 static void* operator new (size_t); 60 static void* operator new[] (size_t); 61 62 public: 63 // Constructor to support creation from a LogTarget instance. 64 // 65 // LogTarget(Debug, gc) log; 66 // LogStreamBase(log) stream; 67 template <LogLevelType level, LogTagType T0, LogTagType T1, LogTagType T2, LogTagType T3, LogTagType T4, LogTagType GuardTag> 68 LogStream(const LogTargetImpl<level, T0, T1, T2, T3, T4, GuardTag>& type_carrier) : 69 _log_handle(level, &LogTagSetMapping<T0, T1, T2, T3, T4>::tagset()) {} 70 71 // Constructor to support creation from typed (likely NULL) pointer. Mostly used by the logging framework. 72 // 73 // LogStreamBase stream(log.debug()); 74 // or 75 // LogStreamBase stream((LogTargetImpl<level, T0, T1, T2, T3, T4, GuardTag>*)NULL); 76 template <LogLevelType level, LogTagType T0, LogTagType T1, LogTagType T2, LogTagType T3, LogTagType T4, LogTagType GuardTag> 77 LogStream(const LogTargetImpl<level, T0, T1, T2, T3, T4, GuardTag>* type_carrier) : 78 _log_handle(level, &LogTagSetMapping<T0, T1, T2, T3, T4>::tagset()) {} 79 80 // Constructor to support creation from a LogTargetHandle. 81 // 82 // LogTarget(Debug, gc) log; 83 // LogTargetHandle(log) handle; 84 // LogStreamBase stream(handle); 85 LogStream(LogTargetHandle handle) : _log_handle(handle) {} 86 87 // Constructor to support creation from a log level and tagset. 88 // 89 // LogStreamBase(level, tageset); 90 LogStream(LogLevelType level, LogTagSet* tagset) : _log_handle(level, tagset) {} 91 92 void write(const char* s, size_t len); 93 }; 94 95 // Support creation of a LogStream without having to provide a LogTarget pointer. 96 #define LogStreamHandle(level, ...) LogStreamTemplate<LogLevel::level, LOG_TAGS(__VA_ARGS__)> 97 98 template <LogLevelType level, LogTagType T0, LogTagType T1, LogTagType T2, LogTagType T3, LogTagType T4, LogTagType GuardTag> 99 class LogStreamTemplate : public LogStream { 100 public: 101 LogStreamTemplate() : LogStream((LogTargetImpl<level, T0, T1, T2, T3, T4, GuardTag>*)NULL) {} 102 }; 103 104 #endif // SHARE_VM_LOGGING_LOGSTREAM_HPP