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 #include "precompiled.hpp" 26 #include "logging/log.hpp" 27 #include "logging/logStream.hpp" 28 #include "logging/logMessageBuffer.hpp" 29 #include "logging/logAsyncFlusher.hpp" 30 31 LogStream::LineBuffer::LineBuffer() 32 : _buf(_smallbuf), _cap(sizeof(_smallbuf)), _pos(0) 33 { 34 _buf[0] = '\0'; 35 } 36 37 LogStream::LineBuffer::~LineBuffer() { 38 assert(_pos == 0, "still outstanding bytes in the line buffer"); 39 if (_buf != _smallbuf) { 40 os::free(_buf); 41 } 42 } 43 44 // try_ensure_cap tries to enlarge the capacity of the internal buffer 45 // to the given atleast value. May fail if either OOM happens or atleast 46 // is larger than a reasonable max of 1 M. Caller must not assume 47 // capacity without checking. 48 void LogStream::LineBuffer::try_ensure_cap(size_t atleast) { 49 assert(_cap >= sizeof(_smallbuf), "sanity"); 50 if (_cap < atleast) { 51 // Cap out at a reasonable max to prevent runaway leaks. 52 const size_t reasonable_max = 1 * M; 53 assert(_cap <= reasonable_max, "sanity"); 54 if (_cap == reasonable_max) { 55 return; 56 } 57 58 const size_t additional_expansion = 256; 59 size_t newcap = align_up(atleast + additional_expansion, additional_expansion); 60 if (newcap > reasonable_max) { 61 log_info(logging)("Suspiciously long log line: \"%.100s%s", 62 _buf, (_pos >= 100 ? "..." : "")); 63 newcap = reasonable_max; 64 } 65 66 char* const newbuf = (char*) os::malloc(newcap, mtLogging); 67 if (newbuf == NULL) { // OOM. Leave object unchanged. 68 return; 69 } 70 if (_pos > 0) { // preserve old content 71 memcpy(newbuf, _buf, _pos + 1); // ..including trailing zero 72 } 73 if (_buf != _smallbuf) { 74 os::free(_buf); 75 } 76 _buf = newbuf; 77 _cap = newcap; 78 } 79 assert(_cap >= atleast, "sanity"); 80 } 81 82 void LogStream::LineBuffer::append(const char* s, size_t len) { 83 assert(_buf[_pos] == '\0', "sanity"); 84 assert(_pos < _cap, "sanity"); 85 const size_t minimum_capacity_needed = _pos + len + 1; 86 try_ensure_cap(minimum_capacity_needed); 87 // try_ensure_cap may not have enlarged the capacity to the full requested 88 // extend or may have not worked at all. In that case, just gracefully work 89 // with what we have already; just truncate if necessary. 90 if (_cap < minimum_capacity_needed) { 91 len = _cap - _pos - 1; 92 if (len == 0) { 93 return; 94 } 95 } 96 memcpy(_buf + _pos, s, len); 97 _pos += len; 98 _buf[_pos] = '\0'; 99 } 100 101 void LogStream::LineBuffer::reset() { 102 _pos = 0; 103 _buf[_pos] = '\0'; 104 } 105 106 void LogStream::write(const char* s, size_t len) { 107 if (len > 0 && s[len - 1] == '\n') { 108 _current_line.append(s, len - 1); // omit the newline. 109 if (!_async_log) { 110 _log_handle.print("%s", _current_line.buffer()); 111 } else { 112 if (!_async_buffer) { 113 _async_buffer = new (mtLogging)LogMessageBuffer(); 114 } 115 _async_buffer->write_n(_log_handle.level(), _current_line.buffer(), _current_line.size()); 116 } 117 _current_line.reset(); 118 } else { 119 _current_line.append(s, len); 120 } 121 122 update_position(s, len); 123 } 124 125 // Destructor writes any unfinished output left in the line buffer. 126 LogStream::~LogStream() { 127 if (!_current_line.is_empty()) { 128 if (!_async_log) { 129 _log_handle.print("%s", _current_line.buffer()); 130 } 131 else { 132 if (!_async_buffer) { 133 _async_buffer = new (mtLogging)LogMessageBuffer(); 134 } 135 _async_buffer->write_n(_log_handle.level(), _current_line.buffer(), _current_line.size()); 136 } 137 _current_line.reset(); 138 } 139 140 if (_async_log && _async_buffer) { 141 LogAsyncFlusher* flusher = LogAsyncFlusher::instance(); 142 flusher->enqueue(_log_handle.tagset(), _async_buffer); 143 } 144 } 145 146 void LogStream::create_async_buffer() { 147 Arena* arena = new (mtLogging)Arena(mtLogging, LogMessageBuffer::initial_buffer_size()); 148 _async_buffer = new (mtLogging)LogMessageBuffer(arena); 149 }