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 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
109 // Time stamp
110 TimeStamp& time_stamp() { return _stamp; }
111 void stamp();
112 void stamp(bool guard, const char* prefix, const char* suffix);
113 void stamp(bool guard) {
114 stamp(guard, "", ": ");
115 }
116 // Date stamp
117 void date_stamp(bool guard, const char* prefix, const char* suffix);
118 // A simplified call that includes a suffix of ": "
119 void date_stamp(bool guard) {
120 date_stamp(guard, "", ": ");
121 }
122
123 // portable printing of 64 bit integers
124 void print_jlong(jlong value);
125 void print_julong(julong value);
126
127 // flushing
128 virtual void flush() {}
129 virtual void write(const char* str, size_t len) = 0;
130 virtual void rotate_log(bool force, outputStream* out = NULL) {} // GC log rotation
131 virtual ~outputStream() {} // close properly on deletion
132
133 // Caller may specify their own scratch buffer to use for printing; otherwise,
134 // an automatic buffer on the stack (with O_BUFLEN len) is used.
135 void set_scratch_buffer(char* p, size_t len) { _scratch = p; _scratch_len = len; }
136
137 void dec_cr() { dec(); cr(); }
138 void inc_cr() { inc(); cr(); }
139 };
140
141 // standard output
142 // ANSI C++ name collision
143 extern outputStream* tty; // tty output
144
145 class streamIndentor : public StackObj {
146 private:
147 outputStream* _str;
148 int _amount;
149
150 public:
151 streamIndentor(outputStream* str, int amt = 2) : _str(str), _amount(amt) {
152 _str->inc(_amount);
153 }
154 ~streamIndentor() { _str->dec(_amount); }
155 };
156
157 // advisory locking for the shared tty stream:
158 class ttyLocker: StackObj {
159 friend class ttyUnlocker;
160 private:
161 intx _holder;
162
163 public:
164 static intx hold_tty(); // returns a "holder" token
165 static void release_tty(intx holder); // must witness same token
166 static bool release_tty_if_locked(); // returns true if lock was released
167 static void break_tty_lock_for_safepoint(intx holder);
168
169 ttyLocker() { _holder = hold_tty(); }
170 ~ttyLocker() { release_tty(_holder); }
171 };
172
173 // Release the tty lock if it's held and reacquire it if it was
174 // locked. Used to avoid lock ordering problems.
175 class ttyUnlocker: StackObj {
176 private:
177 bool _was_locked;
178 public:
179 ttyUnlocker() {
180 _was_locked = ttyLocker::release_tty_if_locked();
181 }
182 ~ttyUnlocker() {
183 if (_was_locked) {
184 ttyLocker::hold_tty();
185 }
186 }
187 };
188
189 // for writing to strings; buffer will expand automatically
190 class stringStream : public outputStream {
191 protected:
192 char* buffer;
193 size_t buffer_pos;
194 size_t buffer_length;
195 bool buffer_fixed;
196 DEBUG_ONLY(ResourceMark* rm;)
197 public:
198 stringStream(size_t initial_bufsize = 256);
199 stringStream(char* fixed_buffer, size_t fixed_buffer_size);
200 ~stringStream();
201 virtual void write(const char* c, size_t len);
202 size_t size() { return buffer_pos; }
203 const char* base() { return buffer; }
204 void reset() { buffer_pos = 0; _precount = 0; _position = 0; }
205 char* as_string();
206 };
207
208 class fileStream : public outputStream {
209 protected:
210 FILE* _file;
211 bool _need_close;
212 public:
213 fileStream() { _file = NULL; _need_close = false; }
214 fileStream(const char* file_name);
215 fileStream(const char* file_name, const char* opentype);
216 fileStream(FILE* file, bool need_close = false) { _file = file; _need_close = need_close; }
217 ~fileStream();
218 bool is_open() const { return _file != NULL; }
219 virtual void write(const char* c, size_t len);
220 size_t read(void *data, size_t size, size_t count) { return ::fread(data, size, count, _file); }
221 char* readln(char *data, int count);
222 int eof() { return feof(_file); }
223 long fileSize();
224 void rewind() { ::rewind(_file); }
225 void flush();
226 };
227
228 CDS_ONLY(extern fileStream* classlist_file;)
229
230 // unlike fileStream, fdStream does unbuffered I/O by calling
231 // open() and write() directly. It is async-safe, but output
232 // from multiple thread may be mixed together. Used by fatal
233 // error handler.
234 class fdStream : public outputStream {
235 protected:
236 int _fd;
237 public:
238 fdStream(int fd = -1) : _fd(fd) { }
239 bool is_open() const { return _fd != -1; }
240 void set_fd(int fd) { _fd = fd; }
241 int fd() const { return _fd; }
242 virtual void write(const char* c, size_t len);
243 void flush() {};
244 };
245
246 void ostream_init();
247 void ostream_init_log();
248 void ostream_exit();
249 void ostream_abort();
250
251 // In the non-fixed buffer case an underlying buffer will be created and
252 // managed in C heap. Not MT-safe.
253 class bufferedStream : public outputStream {
254 protected:
255 char* _buffer;
256 size_t _pos;
257 size_t _capacity;
258 const bool _owned;
259 const size_t _max_capacity;
260 const size_t _flush_threshold;
261 public:
262 // Construct a stream which allocates its buffer from C heap up to a maximum of max_bufsize
263 bufferedStream(size_t initial_capacity = 256, size_t max_capacity = 10 * M, size_t flush_threshold = 10 * M);
264 // Construct a stream which uses a caller provided buffer
265 bufferedStream(char* fixed_buffer, size_t max_bufsize, size_t flush_threshold = 10 * M);
266 ~bufferedStream();
267 virtual void write(const char* c, size_t len);
268 size_t size() { return _pos; }
269 const char* base() { return _buffer; }
270 void reset() { _pos = 0; _precount = 0; _position = 0; }
271 char* as_string();
272 };
273
274 #define O_BUFLEN 2000 // max size of output of individual print() methods
275
276 #ifndef PRODUCT
277
278 class networkStream : public bufferedStream {
279
280 private:
281 int _socket;
282
283 public:
284 networkStream();
285 ~networkStream();
286
287 bool connect(const char *host, short port);
288 bool is_open() const { return _socket != -1; }
289 int read(char *buf, size_t len);
290 void close();
291 virtual void flush();
292 };
293
294 #endif
295
296 #endif // SHARE_UTILITIES_OSTREAM_HPP