1 /*
   2  * Copyright (c) 2003, 2004, 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 class defaultStream : public xmlTextStream {
  26   friend void ostream_abort();
  27  public:
  28   enum { NO_WRITER = -1 };
  29  private:
  30   bool         _inited;
  31   fileStream*  _log_file;  // XML-formatted file shared by all threads
  32   static int   _output_fd;
  33   static int   _error_fd;
  34   static FILE* _output_stream;
  35   static FILE* _error_stream;
  36 
  37   void init();
  38   void init_log();
  39   void finish_log();
  40   void finish_log_on_error(char *buf, int buflen);
  41  public:
  42   // must defer time stamp due to the fact that os::init() hasn't
  43   // yet been called and os::elapsed_counter() may not be valid
  44   defaultStream() {
  45     _log_file = NULL;
  46     _inited = false;
  47     _writer = -1;
  48     _last_writer = -1;
  49   }
  50 
  51   ~defaultStream() {
  52     if (has_log_file())  finish_log();
  53   }
  54 
  55   static inline FILE* output_stream() {
  56     return DisplayVMOutputToStderr ? _error_stream : _output_stream;
  57   }
  58   static inline FILE* error_stream() {
  59     return DisplayVMOutputToStdout ? _output_stream : _error_stream;
  60   }
  61   static inline int output_fd() {
  62     return DisplayVMOutputToStderr ? _error_fd : _output_fd;
  63   }
  64   static inline int error_fd() {
  65     return DisplayVMOutputToStdout ? _output_fd : _error_fd;
  66   }
  67 
  68   virtual void write(const char* s, size_t len);
  69 
  70   void flush() {
  71     // once we can determine whether we are in a signal handler, we
  72     // should add the following assert here:
  73     // assert(xxxxxx, "can not flush buffer inside signal handler");
  74     xmlTextStream::flush();
  75     fflush(output_stream());
  76     if (has_log_file()) _log_file->flush();
  77   }
  78 
  79   // advisory lock/unlock of _writer field:
  80  private:
  81   intx _writer;    // thread_id with current rights to output
  82   intx _last_writer;
  83  public:
  84   intx hold(intx writer_id);
  85   void release(intx holder);
  86   intx writer() { return _writer; }
  87   bool has_log_file();
  88 
  89   static defaultStream* instance;  // sole instance
  90 };