File: dispatcher.h

package info (click to toggle)
arts 1.5.9-2
  • links: PTS, VCS
  • area: main
  • in suites: lenny
  • size: 8,436 kB
  • ctags: 9,848
  • sloc: ansic: 44,670; cpp: 33,776; sh: 10,486; perl: 3,470; makefile: 372; yacc: 347; lex: 160
file content (265 lines) | stat: -rw-r--r-- 7,152 bytes parent folder | download | duplicates (4)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
    /*

    Copyright (C) 2000 Stefan Westerfeld
                       stefan@space.twc.de

    This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Library General Public
    License as published by the Free Software Foundation; either
    version 2 of the License, or (at your option) any later version.
  
    This library is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
    Library General Public License for more details.
   
    You should have received a copy of the GNU Library General Public License
    along with this library; see the file COPYING.LIB.  If not, write to
    the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
    Boston, MA 02111-1307, USA.

    */

#ifndef DISPATCHER_H
#define DISPATCHER_H

#include "common.h"
#include "pool.h"
#include "iomanager.h"
#include "tcpserver.h"
#include "unixserver.h"
#include "connection.h"
#include "notification.h"

#include <deque>
#include <stack>
#include <vector>
#include <list>
#include "arts_export.h"

/*
 * BC - Status (2002-03-08): Dispatcher
 *
 * This is part of the public API (and interacts with generated code) and
 * has to be kept binary compatible.
 */

namespace Arts {

class ObjectReference;
class FlowSystem_impl;
class GlobalComm;
class InterfaceRepo;
class ObjectManager;
class Object_skel;
class ReferenceClean;
class DelayedReturn;

extern "C" {
  typedef void (*mcop_sighandler)(int); 
}

class ARTS_EXPORT Dispatcher {
private:
	class DispatcherPrivate *d;

protected:
	static Dispatcher *_instance;

	Pool<Buffer> requestResultPool;
	Pool<Object_skel> objectPool;
	std::list<Connection *> connections;

	std::string serverID;
	void generateServerID();	// helper function

	bool deleteIOManagerOnExit;

	TCPServer *tcpServer;
	UnixServer *unixServer;
	IOManager *_ioManager;
	FlowSystem_impl *_flowSystem;
	ObjectManager *objectManager;
	ReferenceClean *referenceClean;
	NotificationManager *notificationManager;

	mcop_sighandler orig_sigpipe;		// original signal handler for SIG_PIPE
	Connection *_activeConnection;		// internal use only (for refcounting)

	/**
	 * connects to a given URL
	 *
	 * @returns a valid connection, or a 0 pointer on error
	 */
	Connection *connectUrl(const std::string& url);

public:
	enum StartServer {
		noServer = 0,					// don't be a server
		startUnixServer = 1,			// listen on a unix domain socket
		startTCPServer = 2,				// listen on a tcp port
		noAuthentication = 4			// don't require authentication
	};

	Dispatcher(IOManager *ioManager = 0, StartServer startServer = noServer);
	~Dispatcher();

	static Dispatcher *the();
	inline IOManager *ioManager() { return _ioManager; };
	InterfaceRepo interfaceRepo();
	FlowSystem_impl *flowSystem();
	GlobalComm globalComm();
	void setFlowSystem(FlowSystem_impl *fs);

	void refillRequestIDs();

	// blocking wait for result
	Buffer *waitForResult(long requestID,Connection *connection);

	// request creation for oneway and twoway requests
	Buffer *createRequest(long& requestID, long objectID, long methodID);
	Buffer *createOnewayRequest(long objectID, long methodID);

	// processes messages
	void handle(Connection *conn, Buffer *buffer, long messageType);

	/*
	 * special hook to handle corrupt messages
	 */
	void handleCorrupt(Connection *conn);

	/**
	 * object registration
	 * 
	 * do not call manually, this is used by the Object_skel constructor
	 * to register itself
	 */
	long addObject(Object_skel *object);

	/**
	 * object deregistration
	 *
	 * do not call manually, this is called by the Object_skel destructor
	 * as soon as the object is deleted
	 */
	void removeObject(long objectID);

	/**
	 * connects to a local object, returning a readily casted "interface" *
	 * if success, or NULL if this object is not local
	 */
	void *connectObjectLocal(ObjectReference& reference, const std::string& interface);

	/**
	 * connects to a remote object, establishing a connection if necessary
	 *
	 * returns NULL if connecting fails or object isn't present or whatever
	 * else could go wrong
	 */
	Connection *connectObjectRemote(ObjectReference& reference);

	/**
	 * stringification of objects (only used by the object implementations,
	 * which in turn provide a _toString method)
	 */
	std::string objectToString(long objectID);

	/**
	 * destringification of objects (mainly used by the object implementations,
	 * which in turn provide a _fromString method)
	 */
	bool stringToObjectReference(ObjectReference& r, const std::string& s);

	/**
	 * main loop
	 */
	void run();

	/**
	 * this function quits the main loop (it must be running, of course)
	 * and causes the run() function to return.
	 */
	void terminate();

	/**
	 * Is called by the transport services as soon as a new connection is
	 * created - this will send authentication request, etc.
	 */
	void initiateConnection(Connection *connection);

	/**
	 * Is called by the Connection as soon as the connection goes down,
	 * which may happen due to a normal cause (client exits), and may
	 * happen if an error occurs as well (network down)
	 */
	void handleConnectionClose(Connection *connection);

	/**
	 * Locks the dispatcher. Whenever you want to do anything with any kind
	 * of aRts object, you will hold a lock on Arts::Dispatcher. There is
	 * only one exception to the rule, and that is: you don't have to lock
	 * the dispatcher when the lock is already held.
	 *
	 * Generally, that is very often the case. Typical situations where you
	 * don't need to lock() the Dispatcher are:
	 *
	 *  @li you receive a callback from the IOManager (timer or fd)
	 *  @li you get call due to some MCOP request
	 *  @li you are called from the NotificationManager
	 *  @li you are called from the FlowSystem (calculateBlock)
	 */
	static void lock();

	/**
	 * Unlocks the dispatcher. Do this to release a lock you hold on
	 * the Arts::Dispatcher.
	 */
	static void unlock();

	/**
	 * Wakes the dispatcher - normally, the dispatcher will go to sleep in
	 * it's event loop, when nothing is to be done. If you change things from
	 * another thread, like: add a new Timer, write something to a connection,
	 * and so on, the dispatcher will not notice it. To wake the dispatcher
	 * up, this call is provided.
	 */
	static void wakeUp();

	/**
	 * - internal usage only -
	 *
	 * this will return the Connection the last request came from
	 */
	Connection *activeConnection();

	/**
	 * - internal usage only -
	 *
	 * this will return a loopback Connection for sending requests to myself
	 */
	Connection *loopbackConnection();

	/**
	 * - internal usage only -
	 *
	 * this will cause a function to return from a request later
	 * @see DelayedReturn
	 */
	DelayedReturn *delayReturn();	

	/**
	 * - internal usage only -
	 *
	 * gets object with a given ID
	 * @returns the object if successful, 0 otherwise
	 */
	Object_skel *getLocalObject(long ID);

	/**
	 * reloads the trader data (do this if things have been added/changed
	 * there)
	 */
	void reloadTraderData();
};
}
#endif