1 /*
2 * Copyright (c) 1997, 2016, 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 "utilities/globalDefinitions.hpp"
31
32 DEBUG_ONLY(class ResourceMark;)
33
34 // Output streams for printing
35 //
36 // Printing guidelines:
37 // Where possible, please use tty->print() and tty->print_cr().
38 // For product mode VM warnings use warning() which internally uses tty.
39 // In places where tty is not initialized yet or too much overhead,
40 // we may use jio_printf:
41 // jio_fprintf(defaultStream::output_stream(), "Message");
42 // This allows for redirection via -XX:+DisplayVMOutputToStdout and
43 // -XX:+DisplayVMOutputToStderr
44 class outputStream : public ResourceObj {
45 protected:
46 int _indentation; // current indentation
47 int _width; // width of the page
48 int _position; // position on the current line
49 int _newlines; // number of '\n' output so far
50 julong _precount; // number of chars output, less _position
51 TimeStamp _stamp; // for time stamps
52 char* _scratch; // internal scratch buffer for printf
53 size_t _scratch_len; // size of internal scratch buffer
54
55 void update_position(const char* s, size_t len);
56 static const char* do_vsnprintf(char* buffer, size_t buflen,
57 const char* format, va_list ap,
58 bool add_cr,
59 size_t& result_len) ATTRIBUTE_PRINTF(3, 0);
60
61 // calls do_vsnprintf and writes output to stream; uses an on-stack buffer.
62 void do_vsnprintf_and_write_with_automatic_buffer(const char* format, va_list ap, bool add_cr) ATTRIBUTE_PRINTF(2, 0);
63 // calls do_vsnprintf and writes output to stream; uses the user-provided buffer;
64 void do_vsnprintf_and_write_with_scratch_buffer(const char* format, va_list ap, bool add_cr) ATTRIBUTE_PRINTF(2, 0);
65 // calls do_vsnprintf, then writes output to stream.
66 void do_vsnprintf_and_write(const char* format, va_list ap, bool add_cr) ATTRIBUTE_PRINTF(2, 0);
67
68 public:
69 // creation
70 outputStream(int width = 80);
71 outputStream(int width, bool has_time_stamps);
72
73 // indentation
74 outputStream& indent();
75 void inc() { _indentation++; };
76 void dec() { _indentation--; };
77 void inc(int n) { _indentation += n; };
78 void dec(int n) { _indentation -= n; };
79 int indentation() const { return _indentation; }
80 void set_indentation(int i) { _indentation = i; }
81 void fill_to(int col);
82 void move_to(int col, int slop = 6, int min_space = 2);
83
84 // sizing
85 int width() const { return _width; }
86 int position() const { return _position; }
87 int newlines() const { return _newlines; }
88 julong count() const { return _precount + _position; }
89 void set_count(julong count) { _precount = count - _position; }
90 void set_position(int pos) { _position = pos; }
91
92 // printing
93 void print(const char* format, ...) ATTRIBUTE_PRINTF(2, 3);
94 void print_cr(const char* format, ...) ATTRIBUTE_PRINTF(2, 3);
95 void vprint(const char *format, va_list argptr) ATTRIBUTE_PRINTF(2, 0);
96 void vprint_cr(const char* format, va_list argptr) ATTRIBUTE_PRINTF(2, 0);
97 void print_raw(const char* str) { write(str, strlen(str)); }
98 void print_raw(const char* str, int len) { write(str, len); }
99 void print_raw_cr(const char* str) { write(str, strlen(str)); cr(); }
100 void print_raw_cr(const char* str, int len){ write(str, len); cr(); }
101 void print_data(void* data, size_t len, bool with_ascii);
102 void put(char ch);
103 void sp(int count = 1);
104 void cr();
105 void cr_indent();
106 void bol() { if (_position > 0) cr(); }
107
108 // Print a human readable size.
109 // byte_size: size, in bytes, to be printed.
110 // scale: one of 1 (byte-wise printing), sizeof(word) (word-size printing), K, M, G (scaled by KB, MB, GB respectively,
111 // or 0, which means the best scale is choosen dynamically.
112 // width: printing width.
113 void print_human_readable_size(size_t byte_size, size_t scale = 0, int width = -1);
114
115 // Prints a percentage value. Values smaller than 1% but not 0 are displayed as "<1%", values
116 // larger than 99% but not 100% are displayed as ">100%".
117 void print_percentage(size_t total, size_t part);
118
119 // Time stamp
120 TimeStamp& time_stamp() { return _stamp; }
121 void stamp();
122 void stamp(bool guard, const char* prefix, const char* suffix);
123 void stamp(bool guard) {
124 stamp(guard, "", ": ");
125 }
126 // Date stamp
127 void date_stamp(bool guard, const char* prefix, const char* suffix);
128 // A simplified call that includes a suffix of ": "
129 void date_stamp(bool guard) {
130 date_stamp(guard, "", ": ");
131 }
132
133 // portable printing of 64 bit integers
134 void print_jlong(jlong value);
135 void print_julong(julong value);
136
137 // flushing
138 virtual void flush() {}
139 virtual void write(const char* str, size_t len) = 0;
140 virtual void rotate_log(bool force, outputStream* out = NULL) {} // GC log rotation
141 virtual ~outputStream() {} // close properly on deletion
142
143 // Caller may specify their own scratch buffer to use for printing; otherwise,
144 // an automatic buffer on the stack (with O_BUFLEN len) is used.
145 void set_scratch_buffer(char* p, size_t len) { _scratch = p; _scratch_len = len; }
146
147 void dec_cr() { dec(); cr(); }
148 void inc_cr() { inc(); cr(); }
149 };
150
151 // standard output
152 // ANSI C++ name collision
153 extern outputStream* tty; // tty output
154
155 class streamIndentor : public StackObj {
156 private:
157 outputStream* _str;
158 int _amount;
159
160 public:
161 streamIndentor(outputStream* str, int amt = 2) : _str(str), _amount(amt) {
162 _str->inc(_amount);
163 }
164 ~streamIndentor() { _str->dec(_amount); }
165 };
166
167 // advisory locking for the shared tty stream:
168 class ttyLocker: StackObj {
169 friend class ttyUnlocker;
170 private:
171 intx _holder;
172
173 public:
174 static intx hold_tty(); // returns a "holder" token
175 static void release_tty(intx holder); // must witness same token
176 static bool release_tty_if_locked(); // returns true if lock was released
177 static void break_tty_lock_for_safepoint(intx holder);
178
179 ttyLocker() { _holder = hold_tty(); }
180 ~ttyLocker() { release_tty(_holder); }
181 };
182
183 // Release the tty lock if it's held and reacquire it if it was
184 // locked. Used to avoid lock ordering problems.
185 class ttyUnlocker: StackObj {
186 private:
187 bool _was_locked;
188 public:
189 ttyUnlocker() {
190 _was_locked = ttyLocker::release_tty_if_locked();
191 }
192 ~ttyUnlocker() {
193 if (_was_locked) {
194 ttyLocker::hold_tty();
195 }
196 }
197 };
198
199 // for writing to strings; buffer will expand automatically
200 class stringStream : public outputStream {
201 protected:
202 char* buffer;
203 size_t buffer_pos;
204 size_t buffer_length;
205 bool buffer_fixed;
206 DEBUG_ONLY(ResourceMark* rm;)
207 public:
208 stringStream(size_t initial_bufsize = 256);
209 stringStream(char* fixed_buffer, size_t fixed_buffer_size);
210 ~stringStream();
211 virtual void write(const char* c, size_t len);
212 size_t size() { return buffer_pos; }
213 const char* base() { return buffer; }
214 void reset() { buffer_pos = 0; _precount = 0; _position = 0; }
215 char* as_string();
216 };
217
218 class fileStream : public outputStream {
219 protected:
220 FILE* _file;
221 bool _need_close;
222 public:
223 fileStream() { _file = NULL; _need_close = false; }
224 fileStream(const char* file_name);
225 fileStream(const char* file_name, const char* opentype);
226 fileStream(FILE* file, bool need_close = false) { _file = file; _need_close = need_close; }
227 ~fileStream();
228 bool is_open() const { return _file != NULL; }
229 void set_need_close(bool b) { _need_close = b;}
230 virtual void write(const char* c, size_t len);
231 size_t read(void *data, size_t size, size_t count) { return ::fread(data, size, count, _file); }
232 char* readln(char *data, int count);
233 int eof() { return feof(_file); }
234 long fileSize();
235 void rewind() { ::rewind(_file); }
236 void flush();
237 };
238
239 CDS_ONLY(extern fileStream* classlist_file;)
240
241 // unlike fileStream, fdStream does unbuffered I/O by calling
242 // open() and write() directly. It is async-safe, but output
243 // from multiple thread may be mixed together. Used by fatal
244 // error handler.
245 class fdStream : public outputStream {
246 protected:
247 int _fd;
248 bool _need_close;
249 public:
250 fdStream(const char* file_name);
251 fdStream(int fd = -1) { _fd = fd; _need_close = false; }
252 ~fdStream();
253 bool is_open() const { return _fd != -1; }
254 void set_fd(int fd) { _fd = fd; _need_close = false; }
255 int fd() const { return _fd; }
256 virtual void write(const char* c, size_t len);
257 void flush() {};
258 };
259
260 void ostream_init();
261 void ostream_init_log();
262 void ostream_exit();
263 void ostream_abort();
264
265 // In the non-fixed buffer case an underlying buffer will be created and
266 // managed in C heap. Not MT-safe.
267 class bufferedStream : public outputStream {
268 protected:
269 char* buffer;
270 size_t buffer_pos;
271 size_t buffer_max;
272 size_t buffer_length;
273 bool buffer_fixed;
274 public:
275 bufferedStream(size_t initial_bufsize = 256, size_t bufmax = 1024*1024*10);
276 bufferedStream(char* fixed_buffer, size_t fixed_buffer_size, size_t bufmax = 1024*1024*10);
277 ~bufferedStream();
278 virtual void write(const char* c, size_t len);
279 size_t size() { return buffer_pos; }
280 const char* base() { return buffer; }
281 void reset() { buffer_pos = 0; _precount = 0; _position = 0; }
282 char* as_string();
283 };
284
285 #define O_BUFLEN 2000 // max size of output of individual print() methods
286
287 #ifndef PRODUCT
288
289 class networkStream : public bufferedStream {
290
291 private:
292 int _socket;
293
294 public:
295 networkStream();
296 ~networkStream();
297
298 bool connect(const char *host, short port);
299 bool is_open() const { return _socket != -1; }
300 int read(char *buf, size_t len);
301 void close();
302 virtual void flush();
303 };
304
305 #endif
306
307 #endif // SHARE_VM_UTILITIES_OSTREAM_HPP