1 /*
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3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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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).
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24 
25 #ifndef SHARE_UTILITIES_DEFAULTSTREAM_HPP
26 #define SHARE_UTILITIES_DEFAULTSTREAM_HPP
27 
28 #include "utilities/xmlstream.hpp"
29 
30 class defaultStream : public xmlTextStream {
31   friend void ostream_abort();
32  public:
33   enum { NO_WRITER = -1 };
34  private:
35   bool         _inited;
36   fileStream*  _log_file;  // XML-formatted file shared by all threads
37   static int   _output_fd;
38   static int   _error_fd;
39   static FILE* _output_stream;
40   static FILE* _error_stream;
41 
42   void init();
43   void init_log();
44   fileStream* open_file(const char* log_name);
45   void start_log();
46   void finish_log();
47   void finish_log_on_error(char *buf, int buflen);
48  public:
49   // must defer time stamp due to the fact that os::init() hasn't
50   // yet been called and os::elapsed_counter() may not be valid
defaultStream()51   defaultStream() {
52     _log_file = NULL;
53     _inited = false;
54     _writer = -1;
55     _last_writer = -1;
56   }
57 
~defaultStream()58   ~defaultStream() {
59     if (has_log_file())  finish_log();
60   }
61 
output_stream()62   static inline FILE* output_stream() {
63     return DisplayVMOutputToStderr ? _error_stream : _output_stream;
64   }
error_stream()65   static inline FILE* error_stream() {
66     return DisplayVMOutputToStdout ? _output_stream : _error_stream;
67   }
output_fd()68   static inline int output_fd() {
69     return DisplayVMOutputToStderr ? _error_fd : _output_fd;
70   }
error_fd()71   static inline int error_fd() {
72     return DisplayVMOutputToStdout ? _output_fd : _error_fd;
73   }
74 
75   virtual void write(const char* s, size_t len);
76 
flush()77   void flush() {
78     // once we can determine whether we are in a signal handler, we
79     // should add the following assert here:
80     // assert(xxxxxx, "can not flush buffer inside signal handler");
81     xmlTextStream::flush();
82     fflush(output_stream());
83     if (has_log_file()) _log_file->flush();
84   }
85 
86   // advisory lock/unlock of _writer field:
87  private:
88   intx _writer;    // thread_id with current rights to output
89   intx _last_writer;
90  public:
91   intx hold(intx writer_id);
92   void release(intx holder);
writer()93   intx writer() { return _writer; }
94   bool has_log_file();
95 
96   static defaultStream* instance;  // sole instance
97 };
98 
99 #endif // SHARE_UTILITIES_DEFAULTSTREAM_HPP
100