1 /*
2 * Copyright (c) 1997, 2019, 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_UTILITIES_OSTREAM_HPP
26 #define SHARE_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 private:
46 outputStream(const outputStream&);
47 outputStream& operator=(const outputStream&);
48
49 protected:
50 int _indentation; // current indentation
51 int _width; // width of the page
52 int _position; // position on the current line
53 int _newlines; // number of '\n' output so far
54 julong _precount; // number of chars output, less _position
55 TimeStamp _stamp; // for time stamps
56 char* _scratch; // internal scratch buffer for printf
57 size_t _scratch_len; // size of internal scratch buffer
58
59 void update_position(const char* s, size_t len);
60 static const char* do_vsnprintf(char* buffer, size_t buflen,
61 const char* format, va_list ap,
62 bool add_cr,
63 size_t& result_len) ATTRIBUTE_PRINTF(3, 0);
64
65 // calls do_vsnprintf and writes output to stream; uses an on-stack buffer.
66 void do_vsnprintf_and_write_with_automatic_buffer(const char* format, va_list ap, bool add_cr) ATTRIBUTE_PRINTF(2, 0);
67 // calls do_vsnprintf and writes output to stream; uses the user-provided buffer;
68 void do_vsnprintf_and_write_with_scratch_buffer(const char* format, va_list ap, bool add_cr) ATTRIBUTE_PRINTF(2, 0);
69 // calls do_vsnprintf, then writes output to stream.
70 void do_vsnprintf_and_write(const char* format, va_list ap, bool add_cr) ATTRIBUTE_PRINTF(2, 0);
71
72 public:
73 // creation
74 outputStream(int width = 80);
75 outputStream(int width, bool has_time_stamps);
76
77 // indentation
78 outputStream& indent();
79 void inc() { _indentation++; };
80 void dec() { _indentation--; };
81 void inc(int n) { _indentation += n; };
82 void dec(int n) { _indentation -= n; };
83 int indentation() const { return _indentation; }
84 void set_indentation(int i) { _indentation = i; }
85 void fill_to(int col);
86 void move_to(int col, int slop = 6, int min_space = 2);
87
88 // sizing
89 int width() const { return _width; }
90 int position() const { return _position; }
91 int newlines() const { return _newlines; }
92 julong count() const { return _precount + _position; }
93 void set_count(julong count) { _precount = count - _position; }
94 void set_position(int pos) { _position = pos; }
95
96 // printing
97 void print(const char* format, ...) ATTRIBUTE_PRINTF(2, 3);
98 void print_cr(const char* format, ...) ATTRIBUTE_PRINTF(2, 3);
99 void vprint(const char *format, va_list argptr) ATTRIBUTE_PRINTF(2, 0);
100 void vprint_cr(const char* format, va_list argptr) ATTRIBUTE_PRINTF(2, 0);
101 void print_raw(const char* str) { write(str, strlen(str)); }
102 void print_raw(const char* str, int len) { write(str, len); }
103 void print_raw_cr(const char* str) { write(str, strlen(str)); cr(); }
104 void print_raw_cr(const char* str, int len){ write(str, len); cr(); }
105 void print_data(void* data, size_t len, bool with_ascii);
106 void put(char ch);
107 void sp(int count = 1);
108 void cr();
109 void cr_indent();
110 void bol() { if (_position > 0) cr(); }
111
112
113 // Time stamp
114 TimeStamp& time_stamp() { return _stamp; }
115 void stamp();
116 void stamp(bool guard, const char* prefix, const char* suffix);
117 void stamp(bool guard) {
118 stamp(guard, "", ": ");
119 }
120 // Date stamp
121 void date_stamp(bool guard, const char* prefix, const char* suffix);
122 // A simplified call that includes a suffix of ": "
123 void date_stamp(bool guard) {
124 date_stamp(guard, "", ": ");
125 }
126
127 // portable printing of 64 bit integers
128 void print_jlong(jlong value);
129 void print_julong(julong value);
130
131 // flushing
132 virtual void flush() {}
133 virtual void write(const char* str, size_t len) = 0;
134 virtual void rotate_log(bool force, outputStream* out = NULL) {} // GC log rotation
135 virtual ~outputStream() {} // close properly on deletion
136
137 // Caller may specify their own scratch buffer to use for printing; otherwise,
138 // an automatic buffer on the stack (with O_BUFLEN len) is used.
139 void set_scratch_buffer(char* p, size_t len) { _scratch = p; _scratch_len = len; }
140
141 void dec_cr() { dec(); cr(); }
142 void inc_cr() { inc(); cr(); }
143 };
144
145 // standard output
146 // ANSI C++ name collision
147 extern outputStream* tty; // tty output
148
149 class streamIndentor : public StackObj {
150 private:
151 outputStream* _str;
152 int _amount;
153
154 public:
155 streamIndentor(outputStream* str, int amt = 2) : _str(str), _amount(amt) {
156 _str->inc(_amount);
157 }
158 ~streamIndentor() { _str->dec(_amount); }
159 };
160
161 // advisory locking for the shared tty stream:
162 class ttyLocker: StackObj {
163 friend class ttyUnlocker;
164 private:
165 intx _holder;
166
167 public:
168 static intx hold_tty(); // returns a "holder" token
169 static void release_tty(intx holder); // must witness same token
170 static bool release_tty_if_locked(); // returns true if lock was released
171 static void break_tty_lock_for_safepoint(intx holder);
172
173 ttyLocker() { _holder = hold_tty(); }
174 ~ttyLocker() { release_tty(_holder); }
175 };
176
177 // Release the tty lock if it's held and reacquire it if it was
178 // locked. Used to avoid lock ordering problems.
179 class ttyUnlocker: StackObj {
180 private:
181 bool _was_locked;
182 public:
183 ttyUnlocker() {
184 _was_locked = ttyLocker::release_tty_if_locked();
185 }
186 ~ttyUnlocker() {
187 if (_was_locked) {
188 ttyLocker::hold_tty();
189 }
190 }
191 };
192
193 // for writing to strings; buffer will expand automatically.
194 // Buffer will always be zero-terminated.
195 class stringStream : public outputStream {
196 protected:
197 char* buffer;
198 size_t buffer_pos;
199 size_t buffer_length;
200 bool buffer_fixed;
201
202 // zero terminate at buffer_pos.
203 void zero_terminate();
204
205 public:
206 // Create a stringStream using an internal buffer of initially initial_bufsize size;
207 // will be enlarged on demand. There is no maximum cap.
208 stringStream(size_t initial_bufsize = 256);
209 // Creates a stringStream using a caller-provided buffer. Will truncate silently if
210 // it overflows.
211 stringStream(char* fixed_buffer, size_t fixed_buffer_size);
212 ~stringStream();
213 virtual void write(const char* c, size_t len);
214 // Return number of characters written into buffer, excluding terminating zero and
215 // subject to truncation in static buffer mode.
216 size_t size() const { return buffer_pos; }
217 const char* base() const { return buffer; }
218 void reset();
219 char* as_string() const;
220 };
221
222 class fileStream : public outputStream {
223 protected:
224 FILE* _file;
225 bool _need_close;
226 public:
227 fileStream() { _file = NULL; _need_close = false; }
228 fileStream(const char* file_name);
229 fileStream(const char* file_name, const char* opentype);
230 fileStream(FILE* file, bool need_close = false) { _file = file; _need_close = need_close; }
231 ~fileStream();
232 bool is_open() const { return _file != NULL; }
233 virtual void write(const char* c, size_t len);
234 size_t read(void *data, size_t size, size_t count) { return ::fread(data, size, count, _file); }
235 char* readln(char *data, int count);
236 int eof() { return feof(_file); }
237 long fileSize();
238 void rewind() { ::rewind(_file); }
239 void flush();
240 };
241
242 CDS_ONLY(extern fileStream* classlist_file;)
243
244 // unlike fileStream, fdStream does unbuffered I/O by calling
245 // open() and write() directly. It is async-safe, but output
246 // from multiple thread may be mixed together. Used by fatal
247 // error handler.
248 class fdStream : public outputStream {
249 protected:
250 int _fd;
251 public:
252 fdStream(int fd = -1) : _fd(fd) { }
253 bool is_open() const { return _fd != -1; }
254 void set_fd(int fd) { _fd = fd; }
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 bool truncated;
275 public:
276 bufferedStream(size_t initial_bufsize = 256, size_t bufmax = 1024*1024*10);
277 bufferedStream(char* fixed_buffer, size_t fixed_buffer_size, size_t bufmax = 1024*1024*10);
278 ~bufferedStream();
279 virtual void write(const char* c, size_t len);
280 size_t size() { return buffer_pos; }
281 const char* base() { return buffer; }
282 void reset() { buffer_pos = 0; _precount = 0; _position = 0; }
283 char* as_string();
284 };
285
286 #define O_BUFLEN 2000 // max size of output of individual print() methods
287
288 #ifndef PRODUCT
289
290 class networkStream : public bufferedStream {
291
292 private:
293 int _socket;
294
295 public:
296 networkStream();
297 ~networkStream();
298
299 bool connect(const char *host, short port);
300 bool is_open() const { return _socket != -1; }
301 int read(char *buf, size_t len);
302 void close();
303 virtual void flush();
304 };
305
306 #endif
307
308 #endif // SHARE_UTILITIES_OSTREAM_HPP