1 /*
2 * Copyright (c) 1997, 2013, 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
31 DEBUG_ONLY(class ResourceMark;)
32
33 // Output streams for printing
34 //
35 // Printing guidelines:
36 // Where possible, please use tty->print() and tty->print_cr().
37 // For product mode VM warnings use warning() which internally uses tty.
38 // In places where tty is not initialized yet or too much overhead,
39 // we may use jio_printf:
40 // jio_fprintf(defaultStream::output_stream(), "Message");
41 // This allows for redirection via -XX:+DisplayVMOutputToStdout and
42 // -XX:+DisplayVMOutputToStderr
43 class outputStream : public ResourceObj {
44 protected:
45 int _indentation; // current indentation
46 int _width; // width of the page
47 int _position; // position on the current line
48 int _newlines; // number of '\n' output so far
49 julong _precount; // number of chars output, less _position
50 TimeStamp _stamp; // for time stamps
51
52 void update_position(const char* s, size_t len);
53 static const char* do_vsnprintf(char* buffer, size_t buflen,
54 const char* format, va_list ap,
55 bool add_cr,
56 size_t& result_len);
57
58 public:
59 // creation
60 outputStream(int width = 80);
61 outputStream(int width, bool has_time_stamps);
62
63 // indentation
64 outputStream& indent();
65 void inc() { _indentation++; };
66 void dec() { _indentation--; };
67 void inc(int n) { _indentation += n; };
68 void dec(int n) { _indentation -= n; };
69 int indentation() const { return _indentation; }
70 void set_indentation(int i) { _indentation = i; }
71 void fill_to(int col);
72 void move_to(int col, int slop = 6, int min_space = 2);
73
74 // sizing
75 int width() const { return _width; }
76 int position() const { return _position; }
77 int newlines() const { return _newlines; }
78 julong count() const { return _precount + _position; }
79 void set_count(julong count) { _precount = count - _position; }
80 void set_position(int pos) { _position = pos; }
81
82 // printing
83 void print(const char* format, ...);
84 void print_cr(const char* format, ...);
85 void vprint(const char *format, va_list argptr);
86 void vprint_cr(const char* format, va_list argptr);
87 void print_raw(const char* str) { write(str, strlen(str)); }
88 void print_raw(const char* str, int len) { write(str, len); }
89 void print_raw_cr(const char* str) { write(str, strlen(str)); cr(); }
90 void print_raw_cr(const char* str, int len){ write(str, len); cr(); }
91 void print_data(void* data, size_t len, bool with_ascii);
92 void put(char ch);
93 void sp(int count = 1);
94 void cr();
95 void bol() { if (_position > 0) cr(); }
96
97 // Time stamp
98 TimeStamp& time_stamp() { return _stamp; }
99 void stamp();
100 void stamp(bool guard, const char* prefix, const char* suffix);
101 void stamp(bool guard) {
102 stamp(guard, "", ": ");
103 }
104 // Date stamp
105 void date_stamp(bool guard, const char* prefix, const char* suffix);
106 // A simplified call that includes a suffix of ": "
107 void date_stamp(bool guard) {
108 date_stamp(guard, "", ": ");
109 }
110
111 // portable printing of 64 bit integers
112 void print_jlong(jlong value);
113 void print_julong(julong value);
114
115 // flushing
116 virtual void flush() {}
117 virtual void write(const char* str, size_t len) = 0;
118 virtual void rotate_log(bool force, outputStream* out = NULL) {} // GC log rotation
119 virtual ~outputStream() {} // close properly on deletion
120
121 void dec_cr() { dec(); cr(); }
122 void inc_cr() { inc(); cr(); }
123 };
124
125 // standard output
126 // ANSI C++ name collision
127 extern outputStream* tty; // tty output
128 extern outputStream* gclog_or_tty; // stream for gc log if -Xloggc:<f>, or tty
129
130 class streamIndentor : public StackObj {
131 private:
132 outputStream* _str;
133 int _amount;
134
135 public:
136 streamIndentor(outputStream* str, int amt = 2) : _str(str), _amount(amt) {
137 _str->inc(_amount);
138 }
139 ~streamIndentor() { _str->dec(_amount); }
140 };
141
142
143 // advisory locking for the shared tty stream:
144 class ttyLocker: StackObj {
145 friend class ttyUnlocker;
146 private:
147 intx _holder;
148
149 public:
150 static intx hold_tty(); // returns a "holder" token
151 static void release_tty(intx holder); // must witness same token
152 static bool release_tty_if_locked(); // returns true if lock was released
153 static void break_tty_lock_for_safepoint(intx holder);
154
155 ttyLocker() { _holder = hold_tty(); }
156 ~ttyLocker() { release_tty(_holder); }
157 };
158
159 // Release the tty lock if it's held and reacquire it if it was
160 // locked. Used to avoid lock ordering problems.
161 class ttyUnlocker: StackObj {
162 private:
163 bool _was_locked;
164 public:
165 ttyUnlocker() {
166 _was_locked = ttyLocker::release_tty_if_locked();
167 }
168 ~ttyUnlocker() {
169 if (_was_locked) {
170 ttyLocker::hold_tty();
171 }
172 }
173 };
174
175 // for writing to strings; buffer will expand automatically
176 class stringStream : public outputStream {
177 protected:
178 char* buffer;
179 size_t buffer_pos;
180 size_t buffer_length;
181 bool buffer_fixed;
182 DEBUG_ONLY(ResourceMark* rm;)
183 public:
184 stringStream(size_t initial_bufsize = 256);
185 stringStream(char* fixed_buffer, size_t fixed_buffer_size);
186 ~stringStream();
187 virtual void write(const char* c, size_t len);
188 size_t size() { return buffer_pos; }
189 const char* base() { return buffer; }
190 void reset() { buffer_pos = 0; _precount = 0; _position = 0; }
191 char* as_string();
192 };
193
194 class fileStream : public outputStream {
195 protected:
196 FILE* _file;
197 bool _need_close;
198 public:
199 fileStream() { _file = NULL; _need_close = false; }
200 fileStream(const char* file_name);
201 fileStream(const char* file_name, const char* opentype);
202 fileStream(FILE* file, bool need_close = false) { _file = file; _need_close = need_close; }
203 ~fileStream();
204 bool is_open() const { return _file != NULL; }
205 void set_need_close(bool b) { _need_close = b;}
206 virtual void write(const char* c, size_t len);
207 size_t read(void *data, size_t size, size_t count) { return ::fread(data, size, count, _file); }
208 char* readln(char *data, int count);
209 int eof() { return feof(_file); }
210 long fileSize();
211 void rewind() { ::rewind(_file); }
212 void flush();
213 };
214
215 // unlike fileStream, fdStream does unbuffered I/O by calling
216 // open() and write() directly. It is async-safe, but output
217 // from multiple thread may be mixed together. Used by fatal
218 // error handler.
219 class fdStream : public outputStream {
220 protected:
221 int _fd;
222 bool _need_close;
223 public:
224 fdStream(const char* file_name);
225 fdStream(int fd = -1) { _fd = fd; _need_close = false; }
226 ~fdStream();
227 bool is_open() const { return _fd != -1; }
228 void set_fd(int fd) { _fd = fd; _need_close = false; }
229 int fd() const { return _fd; }
230 virtual void write(const char* c, size_t len);
231 void flush() {};
232 };
233
234 class gcLogFileStream : public fileStream {
235 protected:
236 const char* _file_name;
237 jlong _bytes_written;
238 uintx _cur_file_num; // current logfile rotation number, from 0 to NumberOfGCLogFiles-1
239 public:
240 gcLogFileStream(const char* file_name);
241 ~gcLogFileStream();
242 virtual void write(const char* c, size_t len);
243 virtual void rotate_log(bool force, outputStream* out = NULL);
244 void dump_loggc_header();
245
246 /* If "force" sets true, force log file rotation from outside JVM */
247 bool should_rotate(bool force) {
248 return force ||
249 ((GCLogFileSize != 0) && ((uintx)_bytes_written >= GCLogFileSize));
250 }
251
252 };
253
254 #ifndef PRODUCT
255 // unit test for checking -Xloggc:<filename> parsing result
256 void test_loggc_filename();
257 #endif
258
259 void ostream_init();
260 void ostream_init_log();
261 void ostream_exit();
262 void ostream_abort();
263
264 // staticBufferStream uses a user-supplied buffer for all formatting.
265 // Used for safe formatting during fatal error handling. Not MT safe.
266 // Do not share the stream between multiple threads.
267 class staticBufferStream : public outputStream {
268 private:
269 char* _buffer;
270 size_t _buflen;
271 outputStream* _outer_stream;
272 public:
273 staticBufferStream(char* buffer, size_t buflen,
274 outputStream *outer_stream);
275 ~staticBufferStream() {};
276 virtual void write(const char* c, size_t len);
277 void flush();
278 void print(const char* format, ...);
279 void print_cr(const char* format, ...);
280 void vprint(const char *format, va_list argptr);
281 void vprint_cr(const char* format, va_list argptr);
282 };
283
284 // In the non-fixed buffer case an underlying buffer will be created and
285 // managed in C heap. Not MT-safe.
286 class bufferedStream : public outputStream {
287 protected:
288 char* buffer;
289 size_t buffer_pos;
290 size_t buffer_max;
291 size_t buffer_length;
292 bool buffer_fixed;
293 public:
294 bufferedStream(size_t initial_bufsize = 256, size_t bufmax = 1024*1024*10);
295 bufferedStream(char* fixed_buffer, size_t fixed_buffer_size, size_t bufmax = 1024*1024*10);
296 ~bufferedStream();
297 virtual void write(const char* c, size_t len);
298 size_t size() { return buffer_pos; }
299 const char* base() { return buffer; }
300 void reset() { buffer_pos = 0; _precount = 0; _position = 0; }
301 char* as_string();
302 };
303
304 #define O_BUFLEN 2000 // max size of output of individual print() methods
305
306 #ifndef PRODUCT
307
308 class networkStream : public bufferedStream {
309
310 private:
311 int _socket;
312
313 public:
314 networkStream();
315 ~networkStream();
316
317 bool connect(const char *host, short port);
318 bool is_open() const { return _socket != -1; }
319 int read(char *buf, size_t len);
320 void close();
321 virtual void flush();
322 };
323
324 #endif
325
326 #endif // SHARE_VM_UTILITIES_OSTREAM_HPP