1 /*
2 * Copyright (c) 1997, 2010, 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 // Output streams for printing
32 //
33 // Printing guidelines:
34 // Where possible, please use tty->print() and tty->print_cr().
35 // For product mode VM warnings use warning() which internally uses tty.
36 // In places where tty is not initialized yet or too much overhead,
37 // we may use jio_printf:
38 // jio_fprintf(defaultStream::output_stream(), "Message");
39 // This allows for redirection via -XX:+DisplayVMOutputToStdout and
40 // -XX:+DisplayVMOutputToStderr
41 class outputStream : public ResourceObj {
42 protected:
43 int _indentation; // current indentation
44 int _width; // width of the page
45 int _position; // position on the current line
46 int _newlines; // number of '\n' output so far
47 julong _precount; // number of chars output, less _position
48 TimeStamp _stamp; // for time stamps
49
50 void update_position(const char* s, size_t len);
51 static const char* do_vsnprintf(char* buffer, size_t buflen,
52 const char* format, va_list ap,
53 bool add_cr,
54 size_t& result_len);
55
56 public:
57 // creation
58 outputStream(int width = 80);
59 outputStream(int width, bool has_time_stamps);
60
61 // indentation
62 void indent();
63 void inc() { _indentation++; };
64 void dec() { _indentation--; };
65 int indentation() const { return _indentation; }
66 void set_indentation(int i) { _indentation = i; }
67 void fill_to(int col);
68 void move_to(int col, int slop = 6, int min_space = 2);
69
70 // sizing
71 int width() const { return _width; }
72 int position() const { return _position; }
73 int newlines() const { return _newlines; }
74 julong count() const { return _precount + _position; }
75 void set_count(julong count) { _precount = count - _position; }
76 void set_position(int pos) { _position = pos; }
77
78 // printing
79 void print(const char* format, ...);
80 void print_cr(const char* format, ...);
81 void vprint(const char *format, va_list argptr);
82 void vprint_cr(const char* format, va_list argptr);
83 void print_raw(const char* str) { write(str, strlen(str)); }
84 void print_raw(const char* str, int len) { write(str, len); }
85 void print_raw_cr(const char* str) { write(str, strlen(str)); cr(); }
86 void print_raw_cr(const char* str, int len){ write(str, len); cr(); }
87 void put(char ch);
88 void sp(int count = 1);
89 void cr();
90 void bol() { if (_position > 0) cr(); }
91
92 // Time stamp
93 TimeStamp& time_stamp() { return _stamp; }
94 void stamp();
95 void stamp(bool guard, const char* prefix, const char* suffix);
96 void stamp(bool guard) {
97 stamp(guard, "", ": ");
98 }
99 // Date stamp
100 void date_stamp(bool guard, const char* prefix, const char* suffix);
101 // A simplified call that includes a suffix of ": "
102 void date_stamp(bool guard) {
103 date_stamp(guard, "", ": ");
104 }
105
106 // portable printing of 64 bit integers
107 void print_jlong(jlong value);
108 void print_julong(julong value);
109
110 // flushing
111 virtual void flush() {}
112 virtual void write(const char* str, size_t len) = 0;
113 virtual ~outputStream() {} // close properly on deletion
114
115 void dec_cr() { dec(); cr(); }
116 void inc_cr() { inc(); cr(); }
117 };
118
119 // standard output
120 // ANSI C++ name collision
121 extern outputStream* tty; // tty output
122 extern outputStream* gclog_or_tty; // stream for gc log if -Xloggc:<f>, or tty
123
124 // advisory locking for the shared tty stream:
125 class ttyLocker: StackObj {
126 friend class ttyUnlocker;
127 private:
128 intx _holder;
129
130 public:
131 static intx hold_tty(); // returns a "holder" token
132 static void release_tty(intx holder); // must witness same token
133 static bool release_tty_if_locked(); // returns true if lock was released
134 static void break_tty_lock_for_safepoint(intx holder);
135
136 ttyLocker() { _holder = hold_tty(); }
137 ~ttyLocker() { release_tty(_holder); }
138 };
139
140 // Release the tty lock if it's held and reacquire it if it was
141 // locked. Used to avoid lock ordering problems.
142 class ttyUnlocker: StackObj {
143 private:
144 bool _was_locked;
145 public:
146 ttyUnlocker() {
147 _was_locked = ttyLocker::release_tty_if_locked();
148 }
149 ~ttyUnlocker() {
150 if (_was_locked) {
151 ttyLocker::hold_tty();
152 }
153 }
154 };
155
156 // for writing to strings; buffer will expand automatically
157 class stringStream : public outputStream {
158 protected:
159 char* buffer;
160 size_t buffer_pos;
161 size_t buffer_length;
162 bool buffer_fixed;
163 public:
164 stringStream(size_t initial_bufsize = 256);
165 stringStream(char* fixed_buffer, size_t fixed_buffer_size);
166 ~stringStream();
167 virtual void write(const char* c, size_t len);
168 size_t size() { return buffer_pos; }
169 const char* base() { return buffer; }
170 void reset() { buffer_pos = 0; _precount = 0; _position = 0; }
171 char* as_string();
172 };
173
174 class fileStream : public outputStream {
175 protected:
176 FILE* _file;
177 bool _need_close;
178 public:
179 fileStream(const char* file_name);
180 fileStream(const char* file_name, const char* opentype);
181 fileStream(FILE* file) { _file = file; _need_close = false; }
182 ~fileStream();
183 bool is_open() const { return _file != NULL; }
184 void set_need_close(bool b) { _need_close = b;}
185 virtual void write(const char* c, size_t len);
186 size_t read(void *data, size_t size, size_t count) { return ::fread(data, size, count, _file); }
187 char* readln(char *data, int count);
188 int eof() { return feof(_file); }
189 long fileSize();
190 void rewind() { ::rewind(_file); }
191 void flush();
192 };
193
194 // unlike fileStream, fdStream does unbuffered I/O by calling
195 // open() and write() directly. It is async-safe, but output
196 // from multiple thread may be mixed together. Used by fatal
197 // error handler.
198 class fdStream : public outputStream {
199 protected:
200 int _fd;
201 bool _need_close;
202 public:
203 fdStream(const char* file_name);
204 fdStream(int fd = -1) { _fd = fd; _need_close = false; }
205 ~fdStream();
206 bool is_open() const { return _fd != -1; }
207 void set_fd(int fd) { _fd = fd; _need_close = false; }
208 int fd() const { return _fd; }
209 virtual void write(const char* c, size_t len);
210 void flush() {};
211 };
212
213 void ostream_init();
214 void ostream_init_log();
215 void ostream_exit();
216 void ostream_abort();
217
218 // staticBufferStream uses a user-supplied buffer for all formatting.
219 // Used for safe formatting during fatal error handling. Not MT safe.
220 // Do not share the stream between multiple threads.
221 class staticBufferStream : public outputStream {
222 private:
223 char* _buffer;
224 size_t _buflen;
225 outputStream* _outer_stream;
226 public:
227 staticBufferStream(char* buffer, size_t buflen,
228 outputStream *outer_stream);
229 ~staticBufferStream() {};
230 virtual void write(const char* c, size_t len);
231 void flush();
232 void print(const char* format, ...);
233 void print_cr(const char* format, ...);
234 void vprint(const char *format, va_list argptr);
235 void vprint_cr(const char* format, va_list argptr);
236 };
237
238 // In the non-fixed buffer case an underlying buffer will be created and
239 // managed in C heap. Not MT-safe.
240 class bufferedStream : public outputStream {
241 protected:
242 char* buffer;
243 size_t buffer_pos;
244 size_t buffer_max;
245 size_t buffer_length;
246 bool buffer_fixed;
247 public:
248 bufferedStream(size_t initial_bufsize = 256, size_t bufmax = 1024*1024*10);
249 bufferedStream(char* fixed_buffer, size_t fixed_buffer_size, size_t bufmax = 1024*1024*10);
250 ~bufferedStream();
251 virtual void write(const char* c, size_t len);
252 size_t size() { return buffer_pos; }
253 const char* base() { return buffer; }
254 void reset() { buffer_pos = 0; _precount = 0; _position = 0; }
255 char* as_string();
256 };
257
258 #define O_BUFLEN 2000 // max size of output of individual print() methods
259
260 #ifndef PRODUCT
261
262 class networkStream : public bufferedStream {
263
264 private:
265 int _socket;
266
267 public:
268 networkStream();
269 ~networkStream();
270
271 bool connect(const char *host, short port);
272 bool is_open() const { return _socket != -1; }
273 int read(char *buf, size_t len);
274 void close();
275 virtual void flush();
276 };
277
278 #endif
279
280 #endif // SHARE_VM_UTILITIES_OSTREAM_HPP