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8c15b8c7 TJ |
1 | /* |
2 | The software in this package is distributed under the GNU General | |
3 | Public License version 2 (with a special exception described below). | |
4 | ||
5 | A copy of GNU General Public License (GPL) is included in this distribution, | |
6 | in the file COPYING.GPL. | |
7 | ||
8 | As a special exception, if other files instantiate templates or use macros | |
9 | or inline functions from this file, or you compile this file and link it | |
10 | with other works to produce a work based on this file, this file | |
11 | does not by itself cause the resulting work to be covered | |
12 | by the GNU General Public License. | |
13 | ||
14 | However the source code for this file must still be made available | |
15 | in accordance with section (3) of the GNU General Public License. | |
16 | ||
17 | This exception does not invalidate any other reasons why a work based | |
18 | on this file might be covered by the GNU General Public License. | |
19 | */ | |
20 | /** | |
5c8a3d40 RP |
21 | * @file |
22 | * @brief simple basic IO handling. | |
23 | * | |
24 | * @copyright © Copyright 2007-2008 by Intra2net AG | |
5c8a3d40 RP |
25 | * |
26 | * Deals with POSIX file descriptors; provides an additional abstraction | |
27 | * level above select() or poll() interface. | |
28 | * Also provides basic functionality for dealing with timer events. | |
29 | */ | |
30 | ||
42b7c46d RP |
31 | #ifndef __ASYNC_IO_HPP__ |
32 | #define __ASYNC_IO_HPP__ | |
5c8a3d40 RP |
33 | |
34 | #include <string> | |
35 | #include <list> | |
36 | #include <set> | |
37 | ||
fd6ea89e | 38 | #include <asyncio_config.hpp> |
aba4c34d | 39 | |
fd6ea89e | 40 | #include <asyncio_utils.hpp> |
5c8a3d40 RP |
41 | |
42 | #include <boost/signal.hpp> | |
43 | #include <boost/shared_ptr.hpp> | |
44 | ||
45 | ||
42b7c46d | 46 | namespace AsyncIo |
5c8a3d40 RP |
47 | { |
48 | ||
42b7c46d | 49 | using namespace I2n; |
74786da6 | 50 | |
aba4c34d | 51 | using Utils::MilliTime; |
5c8a3d40 RP |
52 | |
53 | /* | |
54 | * forward declarations | |
55 | */ | |
56 | class Backend; | |
57 | class IOImplementation; | |
58 | ||
59 | /* | |
60 | * end of forward declarations | |
61 | */ | |
62 | ||
63 | ||
64 | /** | |
65 | * direction for io operations. | |
66 | */ | |
67 | struct Direction | |
68 | { | |
69 | enum _Direction | |
70 | { | |
71 | unspecified= 0, | |
72 | in = 1, | |
73 | out = 2, | |
74 | both= 3 | |
75 | } m_direction; | |
76 | ||
77 | Direction( _Direction direction = unspecified) : m_direction(direction) {} | |
78 | ||
79 | operator _Direction () const { return m_direction; } | |
80 | }; // eo struct IODirection; | |
81 | ||
82 | ||
5c8a3d40 RP |
83 | |
84 | /** | |
85 | * base class for time based events (timer events). | |
86 | * | |
87 | * consists basically of a point in time (when the event should be executed) and a method | |
88 | * which will be called when the given time is reached (or passed). | |
89 | */ | |
90 | class TimerBase | |
91 | { | |
92 | friend class Backend; | |
93 | public: | |
94 | TimerBase(); | |
95 | virtual ~TimerBase(); | |
96 | ||
74786da6 | 97 | bool active() const { return m_active; } |
5c8a3d40 RP |
98 | |
99 | MilliTime getWhenTime() const {return m_when;} | |
100 | MilliTime getRealWhenTime() const; | |
101 | ||
102 | protected: | |
103 | ||
104 | void setWhenTime(long sec, long msec=0); | |
105 | void setWhenTime(const MilliTime& mt); | |
106 | ||
107 | void setDeltaWhenTime(long sec, long msec=0); | |
108 | void setDeltaWhenTime(const MilliTime& mt); | |
109 | ||
110 | void activate(bool _active= true); | |
111 | void deactivate() { activate(false); } | |
112 | ||
113 | virtual void execute(); | |
114 | ||
115 | private: | |
116 | /// @a true when the event is active. | |
117 | bool m_active; | |
118 | /// point in time when the event should be executed | |
119 | MilliTime m_when; | |
120 | /// mark from backend cycle that the event has to be executed. | |
121 | bool m_marked; | |
122 | }; // eo class TimerBase | |
123 | ||
124 | ||
125 | ||
126 | /** | |
127 | * base class for filter classes. | |
128 | * | |
129 | * filter objects can be "plugged" into IO objects for manipulating the data streams. | |
130 | * (for example: one could make a filter which handles the telnet protocol and plug it into a | |
131 | * socket io object.) | |
132 | * | |
133 | * @note filter object can be used only by one io object. | |
134 | */ | |
135 | class FilterBase | |
fd6ea89e | 136 | : virtual public Utils::SharedBase |
5c8a3d40 RP |
137 | { |
138 | friend class IOImplementation; | |
139 | public: | |
140 | typedef boost::shared_ptr< FilterBase > PtrType; | |
141 | public: | |
142 | FilterBase(); | |
9f5d794e | 143 | virtual ~FilterBase() { m_io = NULL; }; |
5c8a3d40 RP |
144 | |
145 | protected: | |
146 | ||
147 | virtual std::string filterIncomingData(const std::string& data)= 0; | |
148 | virtual std::string filterOutgoingData(const std::string& data)= 0; | |
149 | ||
150 | virtual void endOfIncomingData(); | |
151 | virtual void reset(); | |
152 | ||
153 | protected: | |
154 | ||
155 | void injectIncomingData(const std::string& data); | |
156 | void injectOutgoingData(const std::string& data); | |
157 | ||
158 | private: | |
159 | /// pointer to the io object which uses this filter: | |
160 | IOImplementation *m_io; | |
161 | }; // eo class FilterBase | |
162 | ||
163 | typedef FilterBase::PtrType FilterBasePtr; | |
164 | ||
165 | ||
166 | /** | |
167 | * identity filter; does nothing with the data (in other words: it's useless ;-) ). | |
168 | */ | |
169 | class FilterIdentity : public FilterBase | |
170 | { | |
171 | protected: | |
172 | virtual std::string filterIncomingData(const std::string& data) { return data; } | |
173 | virtual std::string filterOutgoingData(const std::string& data) { return data; } | |
174 | }; // eo class FilterIdentity | |
175 | ||
176 | ||
177 | /** | |
178 | * @brief null filter; deletes everything it receives. | |
179 | * | |
180 | * usefull when output from a subprocess (like stderr) should be ignored... | |
181 | */ | |
182 | class FilterNull : public FilterBase | |
183 | { | |
184 | protected: | |
185 | virtual std::string filterIncomingData(const std::string& data) { return std::string(); } | |
186 | virtual std::string filterOutgoingData(const std::string& data) { return std::string(); } | |
187 | }; // eo FilterNull | |
188 | ||
189 | ||
190 | /** | |
191 | * the base class of the IO classes. | |
192 | * | |
193 | * provides the functionality to read from a file desriptor and write to a file descriptor (which can be | |
194 | * identical (like for socket io), but also can be different (like pipes from/to a process)). | |
195 | * The data stream can be filtered through plugged filter objects which are building a filter chain. | |
196 | * Incoming data is filtered forward through the chain; outgoing data is filtered backward through the chain. | |
197 | * (So the first filter is the one which modifies the data closest to the connections). | |
198 | * | |
199 | * @note the functionality is provided in conjunction with the @a Backend class which handles parts of | |
200 | * the low level IO. | |
201 | * | |
202 | * @note this is a base class; it provides most "interesting" functionality in the protected section only. | |
203 | * This way, derived classes can decide which of that functionality they want to export in their own public | |
204 | * interfaces and which to keep hidden. | |
205 | */ | |
206 | class IOImplementation | |
207 | : public boost::signals::trackable | |
fd6ea89e | 208 | , virtual public Utils::SharedBase |
5c8a3d40 RP |
209 | { |
210 | friend class Backend; | |
211 | friend class FilterBase; | |
212 | ||
213 | public: | |
214 | ||
215 | typedef std::list< FilterBasePtr > FilterChain; | |
216 | ||
217 | typedef boost::signal< void() > SignalType; | |
218 | ||
219 | typedef boost::shared_ptr< IOImplementation > PtrType; | |
220 | ||
221 | public: | |
222 | IOImplementation(int read_fd=-1, int write_fd=-1); | |
223 | virtual ~IOImplementation(); | |
224 | ||
225 | virtual void close(Direction direction = Direction::both); | |
226 | ||
227 | virtual bool wantRead(); | |
228 | virtual bool wantWrite(); | |
229 | ||
230 | virtual bool opened() const; | |
231 | virtual bool eof() const; | |
232 | virtual bool writable() const; | |
233 | virtual bool empty() const; | |
234 | ||
235 | protected: | |
236 | ||
237 | void addFilter(FilterBasePtr filter); | |
238 | void removeFilter(FilterBasePtr); | |
239 | ||
240 | ||
241 | void lowSend(const std::string& data); | |
242 | ||
243 | std::string::size_type getOutputBufferSize() const { return m_output_buffer.size(); } | |
244 | ||
245 | void setWriteFd(int fd); | |
246 | void setReadFd(int fd); | |
247 | ||
248 | inline int readFd() const | |
249 | { | |
250 | return m_read_fd; | |
251 | } | |
252 | ||
253 | inline int writeFd() const | |
254 | { | |
255 | return m_write_fd; | |
256 | } | |
257 | ||
258 | inline bool isMarkedForReading() const { return m_marked_for_reading; } | |
259 | inline bool isMarkedForWriting() const { return m_marked_for_writing; } | |
260 | ||
261 | ||
262 | protected: | |
263 | virtual void doRead(); | |
264 | virtual void doWrite(); | |
265 | ||
266 | void resetReadMark() { m_marked_for_reading= false; } | |
267 | void resetWriteMark() { m_marked_for_writing= false; } | |
268 | ||
269 | void injectIncomingData(FilterBasePtr from_filter, const std::string& _data); | |
270 | void injectOutgoingData(FilterBasePtr from_filter, const std::string& _data); | |
271 | ||
272 | protected: | |
273 | /// last error number | |
274 | int m_errno; | |
275 | /// the input buffer (i.e. the data read from @a m_read_fd) | |
276 | std::string m_input_buffer; | |
277 | ||
278 | /// the chain of filter which are applied to the data received are the data which should be send. | |
279 | FilterChain m_filter_chain; | |
280 | ||
281 | /// signal which is fired when end of file is detected | |
282 | SignalType m_signal_eof; | |
283 | /// signal which is fired when write is no longer possible | |
284 | SignalType m_signal_not_writable; | |
285 | /// signal which is fired when new data was read | |
286 | SignalType m_signal_read; | |
287 | /// signal which is fired when data was written | |
288 | SignalType m_signal_write; | |
289 | ||
290 | /// end of file (on @a m_read_fd) detected (used additionally when m_read_fd is valid) | |
291 | bool m_eof; | |
292 | ||
293 | /// unable-to-write (on @a m_write_fd) detected (used additionally when m_write_fd is valid) | |
294 | bool m_not_writable; | |
295 | ||
296 | private: | |
297 | /// the file descriptor to read from (-1 if none is given) | |
298 | int m_read_fd; | |
299 | /// the file descriptor to write to (-1 if none is given) | |
300 | int m_write_fd; | |
301 | /// output buffer; contains the data which needs to be written. | |
302 | std::string m_output_buffer; | |
303 | ||
304 | private: | |
305 | /// @a true when data is available to be read | |
306 | bool m_marked_for_reading; | |
307 | /// @a true when data can be written | |
308 | bool m_marked_for_writing; | |
309 | ||
310 | }; // eo class IOImplementation | |
311 | ||
312 | ||
313 | ||
314 | /** | |
315 | * same as IOImplementation, but makes fd access functions public. | |
316 | */ | |
317 | class IOImplementation2 : public IOImplementation | |
318 | { | |
319 | typedef IOImplementation inherited; | |
320 | public: | |
321 | IOImplementation2(int read_fd=-1, int write_fd=-1) : inherited(read_fd, write_fd) {} | |
322 | ||
323 | void setWriteFd(int fd) { inherited::setWriteFd(fd); } | |
324 | void setReadFd(int fd) { inherited::setReadFd(fd); } | |
325 | ||
326 | int readFd() const { return inherited::readFd(); } | |
327 | int writeFd() const { return inherited::writeFd(); } | |
328 | ||
329 | }; // eo class IOImplementation2 | |
330 | ||
331 | ||
332 | /** | |
333 | * provides sending data and receiving data via a signal. | |
334 | * | |
335 | * @note the received data is passed as parameter to the signal and no longer stored in the received buffer. | |
336 | */ | |
337 | class SimpleIO : public IOImplementation | |
338 | { | |
339 | typedef IOImplementation inherited; | |
340 | public: | |
341 | SimpleIO(int read_fd=-1, int write_fd=-1); | |
342 | virtual ~SimpleIO(); | |
343 | ||
344 | void sendString(const std::string& data); | |
345 | ||
346 | boost::signal<void(const std::string&)> signal_received_string; | |
347 | ||
348 | private: | |
349 | ||
350 | void slotReceived(); | |
351 | }; // eo class SimpleIO | |
352 | ||
353 | ||
354 | /** | |
355 | * provides sending data and receiving data via a signal. | |
356 | * | |
357 | * @note the received data is passed as parameter to the signal and no longer stored in the received buffer. | |
358 | */ | |
359 | class SimpleIO2 : public IOImplementation2 | |
360 | { | |
361 | typedef IOImplementation2 inherited; | |
362 | public: | |
363 | SimpleIO2(int read_fd=-1, int write_fd=-1); | |
364 | virtual ~SimpleIO2(); | |
365 | ||
366 | void sendString(const std::string& data); | |
367 | ||
368 | boost::signal<void(const std::string&)> signal_received_string; | |
369 | ||
370 | private: | |
371 | ||
372 | void slotReceived(); | |
373 | }; // eo class SimpleIO2 | |
374 | ||
375 | ||
376 | /** | |
377 | * provides the backend for io handling. | |
378 | * | |
379 | * This (singleton) object provides the management of io events. It collects all wishes for reading/writing | |
380 | * from the io objects and information from the timer events. | |
381 | * It poll()s for the events and distributes them to the objects, | |
382 | * | |
383 | * The class provides the possibility for executing one io cycle (/step) or to run a backend loop. | |
384 | * | |
385 | * @note the Backend class needs to be a friend of IOImplementation since it accesses private members | |
386 | * of IOImplementation while performing the io cycles. | |
387 | */ | |
388 | class Backend | |
389 | { | |
390 | public: | |
391 | typedef std::set< int > FdSetType; | |
392 | ||
393 | public: | |
394 | ||
395 | bool doOneStep(int ms_timeout= -1); | |
396 | void run(); | |
397 | void stop(); | |
398 | ||
399 | protected: | |
400 | Backend(); | |
401 | Backend(const Backend& other); | |
402 | ~Backend(); | |
403 | ||
404 | protected: | |
405 | ||
406 | /// the number of currently active backend loops | |
407 | int m_count_active_loops; | |
408 | /// the number of pending stop requests (where each one should exit one active backend loop) | |
409 | int m_count_stop_requests; | |
410 | ||
411 | /// the number of currently active backend cycles(/ steps) | |
412 | static int m_count_active_steps; | |
413 | ||
414 | public: | |
415 | static Backend* getBackend(); | |
416 | ||
417 | protected: | |
418 | /// pointer to the active backend (which is delivered by Backend::getBackend) | |
419 | static Backend* g_backend; | |
420 | }; // eo class Backend | |
421 | ||
422 | ||
423 | ||
42b7c46d | 424 | } // eo namespace AsyncIo |
5c8a3d40 RP |
425 | |
426 | #endif |