1 /*
2 * Copyright (c) 1997, 2015, 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) ATTRIBUTE_PRINTF(3, 0);
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, ...) ATTRIBUTE_PRINTF(2, 3);
84 void print_cr(const char* format, ...) ATTRIBUTE_PRINTF(2, 3);
85 void vprint(const char *format, va_list argptr) ATTRIBUTE_PRINTF(2, 0);
86 void vprint_cr(const char* format, va_list argptr) ATTRIBUTE_PRINTF(2, 0);
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 void gclog_stamp();
111
112 // portable printing of 64 bit integers
113 void print_jlong(jlong value);
114 void print_julong(julong value);
115
116 // flushing
117 virtual void flush() {}
118 virtual void write(const char* str, size_t len) = 0;
119 virtual void rotate_log(bool force, outputStream* out = NULL) {} // GC log rotation
120 virtual ~outputStream() {} // close properly on deletion
121
122 void dec_cr() { dec(); cr(); }
123 void inc_cr() { inc(); cr(); }
124 };
125
126 // standard output
127 // ANSI C++ name collision
128 extern outputStream* tty; // tty output
129 extern outputStream* gclog_or_tty; // stream for gc log if -Xloggc:<f>, or tty
130
131 class streamIndentor : public StackObj {
132 private:
133 outputStream* _str;
134 int _amount;
135
136 public:
137 streamIndentor(outputStream* str, int amt = 2) : _str(str), _amount(amt) {
138 _str->inc(_amount);
139 }
140 ~streamIndentor() { _str->dec(_amount); }
141 };
142
143
144 // advisory locking for the shared tty stream:
145 class ttyLocker: StackObj {
146 friend class ttyUnlocker;
147 private:
148 intx _holder;
149
150 public:
151 static intx hold_tty(); // returns a "holder" token
152 static void release_tty(intx holder); // must witness same token
153 static bool release_tty_if_locked(); // returns true if lock was released
154 static void break_tty_lock_for_safepoint(intx holder);
155
156 ttyLocker() { _holder = hold_tty(); }
157 ~ttyLocker() { release_tty(_holder); }
158 };
159
160 // Release the tty lock if it's held and reacquire it if it was
161 // locked. Used to avoid lock ordering problems.
162 class ttyUnlocker: StackObj {
163 private:
164 bool _was_locked;
165 public:
166 ttyUnlocker() {
167 _was_locked = ttyLocker::release_tty_if_locked();
168 }
169 ~ttyUnlocker() {
170 if (_was_locked) {
171 ttyLocker::hold_tty();
172 }
173 }
174 };
175
176 // for writing to strings; buffer will expand automatically
177 class stringStream : public outputStream {
178 protected:
179 char* buffer;
180 size_t buffer_pos;
181 size_t buffer_length;
182 bool buffer_fixed;
183 DEBUG_ONLY(ResourceMark* rm;)
184 public:
185 stringStream(size_t initial_bufsize = 256);
186 stringStream(char* fixed_buffer, size_t fixed_buffer_size);
187 ~stringStream();
188 virtual void write(const char* c, size_t len);
189 size_t size() { return buffer_pos; }
190 const char* base() { return buffer; }
191 void reset() { buffer_pos = 0; _precount = 0; _position = 0; }
192 char* as_string();
193 };
194
195 class fileStream : public outputStream {
196 protected:
197 FILE* _file;
198 bool _need_close;
199 public:
200 fileStream() { _file = NULL; _need_close = false; }
201 fileStream(const char* file_name);
202 fileStream(const char* file_name, const char* opentype);
203 fileStream(FILE* file, bool need_close = false) { _file = file; _need_close = need_close; }
204 ~fileStream();
205 bool is_open() const { return _file != NULL; }
206 void set_need_close(bool b) { _need_close = b;}
207 virtual void write(const char* c, size_t len);
208 size_t read(void *data, size_t size, size_t count) { return ::fread(data, size, count, _file); }
209 char* readln(char *data, int count);
210 int eof() { return feof(_file); }
211 long fileSize();
212 void rewind() { ::rewind(_file); }
213 void flush();
214 };
215
216 CDS_ONLY(extern fileStream* classlist_file;)
217
218 // unlike fileStream, fdStream does unbuffered I/O by calling
219 // open() and write() directly. It is async-safe, but output
220 // from multiple thread may be mixed together. Used by fatal
221 // error handler.
222 class fdStream : public outputStream {
223 protected:
224 int _fd;
225 bool _need_close;
226 public:
227 fdStream(const char* file_name);
228 fdStream(int fd = -1) { _fd = fd; _need_close = false; }
229 ~fdStream();
230 bool is_open() const { return _fd != -1; }
231 void set_fd(int fd) { _fd = fd; _need_close = false; }
232 int fd() const { return _fd; }
233 virtual void write(const char* c, size_t len);
234 void flush() {};
235 };
236
237 class gcLogFileStream : public fileStream {
238 protected:
239 const char* _file_name;
240 jlong _bytes_written;
241 uintx _cur_file_num; // current logfile rotation number, from 0 to NumberOfGCLogFiles-1
242 public:
243 gcLogFileStream(const char* file_name);
244 ~gcLogFileStream();
245 virtual void write(const char* c, size_t len);
246 virtual void rotate_log(bool force, outputStream* out = NULL);
247 void dump_loggc_header();
248
249 /* If "force" sets true, force log file rotation from outside JVM */
250 bool should_rotate(bool force) {
251 return force ||
252 ((GCLogFileSize != 0) && (_bytes_written >= (jlong)GCLogFileSize));
253 }
254 };
255
256 #ifndef PRODUCT
257 // unit test for checking -Xloggc:<filename> parsing result
258 void test_loggc_filename();
259 #endif
260
261 void ostream_init();
262 void ostream_init_log();
263 void ostream_exit();
264 void ostream_abort();
265
266 // staticBufferStream uses a user-supplied buffer for all formatting.
267 // Used for safe formatting during fatal error handling. Not MT safe.
268 // Do not share the stream between multiple threads.
269 class staticBufferStream : public outputStream {
270 private:
271 char* _buffer;
272 size_t _buflen;
273 outputStream* _outer_stream;
274 public:
275 staticBufferStream(char* buffer, size_t buflen,
276 outputStream *outer_stream);
277 ~staticBufferStream() {};
278 virtual void write(const char* c, size_t len);
279 void flush();
280 void print(const char* format, ...) ATTRIBUTE_PRINTF(2, 3);
281 void print_cr(const char* format, ...) ATTRIBUTE_PRINTF(2, 3);
282 void vprint(const char *format, va_list argptr) ATTRIBUTE_PRINTF(2, 0);
283 void vprint_cr(const char* format, va_list argptr) ATTRIBUTE_PRINTF(2, 0);
284 };
285
286 // In the non-fixed buffer case an underlying buffer will be created and
287 // managed in C heap. Not MT-safe.
288 class bufferedStream : public outputStream {
289 protected:
290 char* buffer;
291 size_t buffer_pos;
292 size_t buffer_max;
293 size_t buffer_length;
294 bool buffer_fixed;
295 public:
296 bufferedStream(size_t initial_bufsize = 256, size_t bufmax = 1024*1024*10);
297 bufferedStream(char* fixed_buffer, size_t fixed_buffer_size, size_t bufmax = 1024*1024*10);
298 ~bufferedStream();
299 virtual void write(const char* c, size_t len);
300 size_t size() { return buffer_pos; }
301 const char* base() { return buffer; }
302 void reset() { buffer_pos = 0; _precount = 0; _position = 0; }
303 char* as_string();
304 };
305
306 #define O_BUFLEN 2000 // max size of output of individual print() methods
307
308 #ifndef PRODUCT
309
310 class networkStream : public bufferedStream {
311
312 private:
313 int _socket;
314
315 public:
316 networkStream();
317 ~networkStream();
318
319 bool connect(const char *host, short port);
320 bool is_open() const { return _socket != -1; }
321 int read(char *buf, size_t len);
322 void close();
323 virtual void flush();
324 };
325
326 #endif
327
328 #endif // SHARE_VM_UTILITIES_OSTREAM_HPP