1 /*
2 * Copyright (c) 1997, 2014, 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_UTILITIES_OSTREAM_HPP
26 #define SHARE_VM_UTILITIES_OSTREAM_HPP
27
28 #include "memory/allocation.hpp"
29 #include "runtime/timer.hpp"
30 #include "runtime/task.hpp"
31
32 class GCId;
33 DEBUG_ONLY(class ResourceMark;)
34
35 // Output streams for printing
36 //
37 // Printing guidelines:
38 // Where possible, please use tty->print() and tty->print_cr().
39 // For product mode VM warnings use warning() which internally uses tty.
40 // In places where tty is not initialized yet or too much overhead,
41 // we may use jio_printf:
42 // jio_fprintf(defaultStream::output_stream(), "Message");
43 // This allows for redirection via -XX:+DisplayVMOutputToStdout and
44 // -XX:+DisplayVMOutputToStderr
45 class outputStream : public ResourceObj {
46 protected:
47 int _indentation; // current indentation
48 int _width; // width of the page
49 int _position; // position on the current line
50 int _newlines; // number of '\n' output so far
51 julong _precount; // number of chars output, less _position
52 TimeStamp _stamp; // for time stamps
53
54 void update_position(const char* s, size_t len);
55 static const char* do_vsnprintf(char* buffer, size_t buflen,
56 const char* format, va_list ap,
57 bool add_cr,
58 size_t& result_len) ATTRIBUTE_PRINTF(3, 0);
59
60 public:
61 // creation
62 outputStream(int width = 80);
63 outputStream(int width, bool has_time_stamps);
64
65 // indentation
66 outputStream& indent();
67 void inc() { _indentation++; };
68 void dec() { _indentation--; };
69 void inc(int n) { _indentation += n; };
70 void dec(int n) { _indentation -= n; };
71 int indentation() const { return _indentation; }
72 void set_indentation(int i) { _indentation = i; }
73 void fill_to(int col);
74 void move_to(int col, int slop = 6, int min_space = 2);
75
76 // sizing
77 int width() const { return _width; }
78 int position() const { return _position; }
79 int newlines() const { return _newlines; }
80 julong count() const { return _precount + _position; }
81 void set_count(julong count) { _precount = count - _position; }
82 void set_position(int pos) { _position = pos; }
83
84 // printing
85 void print(const char* format, ...) ATTRIBUTE_PRINTF(2, 3);
86 void print_cr(const char* format, ...) ATTRIBUTE_PRINTF(2, 3);
87 void vprint(const char *format, va_list argptr) ATTRIBUTE_PRINTF(2, 0);
88 void vprint_cr(const char* format, va_list argptr) ATTRIBUTE_PRINTF(2, 0);
89 void print_raw(const char* str) { write(str, strlen(str)); }
90 void print_raw(const char* str, int len) { write(str, len); }
91 void print_raw_cr(const char* str) { write(str, strlen(str)); cr(); }
92 void print_raw_cr(const char* str, int len){ write(str, len); cr(); }
93 void print_data(void* data, size_t len, bool with_ascii);
94 void put(char ch);
95 void sp(int count = 1);
96 void cr();
97 void bol() { if (_position > 0) cr(); }
98
99 // Time stamp
100 TimeStamp& time_stamp() { return _stamp; }
101 void stamp();
102 void stamp(bool guard, const char* prefix, const char* suffix);
103 void stamp(bool guard) {
104 stamp(guard, "", ": ");
105 }
106 // Date stamp
107 void date_stamp(bool guard, const char* prefix, const char* suffix);
108 // A simplified call that includes a suffix of ": "
109 void date_stamp(bool guard) {
110 date_stamp(guard, "", ": ");
111 }
112 void gclog_stamp(const GCId& gc_id);
113
114 // portable printing of 64 bit integers
115 void print_jlong(jlong value);
116 void print_julong(julong value);
117
118 // flushing
119 virtual void flush() {}
120 virtual void write(const char* str, size_t len) = 0;
121 virtual void rotate_log(bool force, outputStream* out = NULL) {} // GC log rotation
122 virtual ~outputStream() {} // close properly on deletion
123
124 void dec_cr() { dec(); cr(); }
125 void inc_cr() { inc(); cr(); }
126 };
127
128 // standard output
129 // ANSI C++ name collision
130 extern outputStream* tty; // tty output
131 extern outputStream* gclog_or_tty; // stream for gc log if -Xloggc:<f>, or tty
132
133 class streamIndentor : public StackObj {
134 private:
135 outputStream* _str;
136 int _amount;
137
138 public:
139 streamIndentor(outputStream* str, int amt = 2) : _str(str), _amount(amt) {
140 _str->inc(_amount);
141 }
142 ~streamIndentor() { _str->dec(_amount); }
143 };
144
145
146 // advisory locking for the shared tty stream:
147 class ttyLocker: StackObj {
148 friend class ttyUnlocker;
149 private:
150 intx _holder;
151
152 public:
153 static intx hold_tty(); // returns a "holder" token
154 static void release_tty(intx holder); // must witness same token
155 static bool release_tty_if_locked(); // returns true if lock was released
156 static void break_tty_lock_for_safepoint(intx holder);
157
158 ttyLocker() { _holder = hold_tty(); }
159 ~ttyLocker() { release_tty(_holder); }
160 };
161
162 // Release the tty lock if it's held and reacquire it if it was
163 // locked. Used to avoid lock ordering problems.
164 class ttyUnlocker: StackObj {
165 private:
166 bool _was_locked;
167 public:
168 ttyUnlocker() {
169 _was_locked = ttyLocker::release_tty_if_locked();
170 }
171 ~ttyUnlocker() {
172 if (_was_locked) {
173 ttyLocker::hold_tty();
174 }
175 }
176 };
177
178 // for writing to strings; buffer will expand automatically
179 class stringStream : public outputStream {
180 protected:
181 char* buffer;
182 size_t buffer_pos;
183 size_t buffer_length;
184 bool buffer_fixed;
185 DEBUG_ONLY(ResourceMark* rm;)
186 public:
187 stringStream(size_t initial_bufsize = 256);
188 stringStream(char* fixed_buffer, size_t fixed_buffer_size);
189 ~stringStream();
190 virtual void write(const char* c, size_t len);
191 size_t size() { return buffer_pos; }
192 const char* base() { return buffer; }
193 void reset() { buffer_pos = 0; _precount = 0; _position = 0; }
194 char* as_string();
195 };
196
197 class fileStream : public outputStream {
198 protected:
199 FILE* _file;
200 bool _need_close;
201 public:
202 fileStream() { _file = NULL; _need_close = false; }
203 fileStream(const char* file_name);
204 fileStream(const char* file_name, const char* opentype);
205 fileStream(FILE* file, bool need_close = false) { _file = file; _need_close = need_close; }
206 ~fileStream();
207 bool is_open() const { return _file != NULL; }
208 void set_need_close(bool b) { _need_close = b;}
209 virtual void write(const char* c, size_t len);
210 size_t read(void *data, size_t size, size_t count) { return ::fread(data, size, count, _file); }
211 char* readln(char *data, int count);
212 int eof() { return feof(_file); }
213 long fileSize();
214 void rewind() { ::rewind(_file); }
215 void flush();
216 };
217
218 CDS_ONLY(extern fileStream* classlist_file;)
219
220 // unlike fileStream, fdStream does unbuffered I/O by calling
221 // open() and write() directly. It is async-safe, but output
222 // from multiple thread may be mixed together. Used by fatal
223 // error handler.
224 class fdStream : public outputStream {
225 protected:
226 int _fd;
227 bool _need_close;
228 public:
229 fdStream(const char* file_name);
230 fdStream(int fd = -1) { _fd = fd; _need_close = false; }
231 ~fdStream();
232 bool is_open() const { return _fd != -1; }
233 void set_fd(int fd) { _fd = fd; _need_close = false; }
234 int fd() const { return _fd; }
235 virtual void write(const char* c, size_t len);
236 void flush() {};
237 };
238
239 class Mutex;
240 class GCLogEvent;
241
242 class gcLogFileStream : public fileStream {
243 protected:
244 const char* _file_name;
245 jlong _bytes_written;
246 uintx _cur_file_num; // current logfile rotation number, from 0 to NumberOfGCLogFiles-1
247 private:
248 GCLogEvent* _reader;
249 GCLogEvent* _writer;
250 Mutex* _lock;
251
252 public:
253 gcLogFileStream(const char* file_name);
254 ~gcLogFileStream();
255 // write asynchronously
256 virtual void write(const char* c, size_t len);
257 // really write to file system.
258 void write_blocking(const char* c, size_t len);
259 virtual void rotate_log(bool force, outputStream* out = NULL);
260 void flush_log();
261 void dump_loggc_header();
262
263 /* If "force" sets true, force log file rotation from outside JVM */
264 bool should_rotate(bool force) {
265 return force ||
266 ((GCLogFileSize != 0) && ((uintx)_bytes_written >= GCLogFileSize));
267 }
268
269 };
270
271 class GCLogFlusher: public PeriodicTask {
272 gcLogFileStream * _ostream;
273 elapsedTimer _accumulatedTime;
274 public:
275 GCLogFlusher(int interval, gcLogFileStream* ostream):PeriodicTask(interval), _ostream(ostream) {}
276
277 virtual void task() {
278 TraceTime t("GCLogFlusher", &_accumulatedTime, true, PrintGCLogFlushTime);
279 _ostream->flush_log();
280 }
281
282 elapsedTimer getAccumulatedTime() {
283 return _accumulatedTime;
284 }
285 };
286
287 #ifndef PRODUCT
288 // unit test for checking -Xloggc:<filename> parsing result
289 void test_loggc_filename();
290 void test_snprintf();
291 #endif
292
293 void ostream_init();
294 void ostream_init_log();
295 void ostream_exit();
296 void ostream_abort();
297
298 // staticBufferStream uses a user-supplied buffer for all formatting.
299 // Used for safe formatting during fatal error handling. Not MT safe.
300 // Do not share the stream between multiple threads.
301 class staticBufferStream : public outputStream {
302 private:
303 char* _buffer;
304 size_t _buflen;
305 outputStream* _outer_stream;
306 public:
307 staticBufferStream(char* buffer, size_t buflen,
308 outputStream *outer_stream);
309 ~staticBufferStream() {};
310 virtual void write(const char* c, size_t len);
311 void flush();
312 void print(const char* format, ...) ATTRIBUTE_PRINTF(2, 3);
313 void print_cr(const char* format, ...) ATTRIBUTE_PRINTF(2, 3);
314 void vprint(const char *format, va_list argptr) ATTRIBUTE_PRINTF(2, 0);
315 void vprint_cr(const char* format, va_list argptr) ATTRIBUTE_PRINTF(2, 0);
316 };
317
318 // In the non-fixed buffer case an underlying buffer will be created and
319 // managed in C heap. Not MT-safe.
320 class bufferedStream : public outputStream {
321 protected:
322 char* buffer;
323 size_t buffer_pos;
324 size_t buffer_max;
325 size_t buffer_length;
326 bool buffer_fixed;
327 public:
328 bufferedStream(size_t initial_bufsize = 256, size_t bufmax = 1024*1024*10);
329 bufferedStream(char* fixed_buffer, size_t fixed_buffer_size, size_t bufmax = 1024*1024*10);
330 ~bufferedStream();
331 virtual void write(const char* c, size_t len);
332 size_t size() { return buffer_pos; }
333 const char* base() { return buffer; }
334 void reset() { buffer_pos = 0; _precount = 0; _position = 0; }
335 char* as_string();
336 };
337
338 #define O_BUFLEN 2000 // max size of output of individual print() methods
339
340 #ifndef PRODUCT
341
342 class networkStream : public bufferedStream {
343
344 private:
345 int _socket;
346
347 public:
348 networkStream();
349 ~networkStream();
350
351 bool connect(const char *host, short port);
352 bool is_open() const { return _socket != -1; }
353 int read(char *buf, size_t len);
354 void close();
355 virtual void flush();
356 };
357
358 #endif
359
360 #endif // SHARE_VM_UTILITIES_OSTREAM_HPP