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TSysEvtHandler.cxx
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1// @(#)root/base:$Id$
2// Author: Fons Rademakers 16/09/95
3
4/*************************************************************************
5 * Copyright (C) 1995-2000, Rene Brun and Fons Rademakers. *
6 * All rights reserved. *
7 * *
8 * For the licensing terms see $ROOTSYS/LICENSE. *
9 * For the list of contributors see $ROOTSYS/README/CREDITS. *
10 *************************************************************************/
11
12/** \class TSysEvtHandler
13\ingroup Base
14
15Abstract base class for handling system events.
16*/
17
18#include "TSysEvtHandler.h"
19#include "TSystem.h"
20
21
26
27
28////////////////////////////////////////////////////////////////////////////////
29/// Activate a system event handler. All handlers are by default
30/// activated. Use this method to activate a de-activated handler.
31
33{
35 Activated(); // emit Activated() signal
36}
37
38////////////////////////////////////////////////////////////////////////////////
39/// De-activate a system event handler. Use this method to temporarily
40/// disable an event handler to avoid it from being recursively called.
41/// Use DeActivate() / Activate() instead of Remove() / Add() for this
42/// purpose, since the Add() will add the handler back to the end of
43/// the list of handlers and cause it to be called again for the same,
44/// already handled, event.
45
47{
49 DeActivated(); // emit DeActivated() signal
50}
51
52
53////////////////////////////////////////////////////////////////////////////////
54/// Create a file descriptor event handler. If mask=kRead then we
55/// want to monitor the file for read readiness, if mask=kWrite
56/// then we monitor the file for write readiness, if mask=kRead|kWrite
57/// then we monitor both read and write readiness.
58
60{
61 fFileNum = fd;
62 if (!mask)
63 mask = kRead;
64 fMask = mask;
65 fReadyMask = 0;
66}
67
68////////////////////////////////////////////////////////////////////////////////
69/// Notify when event occurred on descriptor associated with this handler.
70
72{
73 Notified(); // emit Notified() signal
74 return kFALSE;
75}
76
77////////////////////////////////////////////////////////////////////////////////
78/// Notify when something can be read from the descriptor associated with
79/// this handler.
80
82{
83 Notified(); // emit Notified() signal
84 return kFALSE;
85}
86
87////////////////////////////////////////////////////////////////////////////////
88/// Notify when something can be written to the descriptor associated with
89/// this handler.
90
92{
93 Notified(); // emit Notified() signal
94 return kFALSE;
95}
96
97////////////////////////////////////////////////////////////////////////////////
98/// True if handler is interested in read events.
99
101{
102 return (fMask & 1);
103}
104
105////////////////////////////////////////////////////////////////////////////////
106/// True if handler is interested in write events.
107
109{
110 return (fMask & 2);
111}
112
113////////////////////////////////////////////////////////////////////////////////
114/// Set interest mask to 'mask'.
115
117{
118 if (!mask)
119 mask = kRead;
120 fMask = mask;
121}
122
123////////////////////////////////////////////////////////////////////////////////
124/// Add file event handler to system file handler list.
125
127{
128 if (gSystem && fFileNum != -1) {
129 gSystem->AddFileHandler(this);
130 Added(); // emit Added() signal
131 }
132}
133
134////////////////////////////////////////////////////////////////////////////////
135/// Remove file event handler from system file handler list.
136
138{
139 if (gSystem && fFileNum != -1) {
141 Removed(); // emit Removed() signal
142 }
143}
144
145
146////////////////////////////////////////////////////////////////////////////////
147/// Create signal event handler.
148
150{
151 fSignal = sig;
152 fSync = sync;
153 fDelay = 0;
154}
155
156////////////////////////////////////////////////////////////////////////////////
157/// Notify when signal occurs.
158
160{
161 Notified(); // emit Notified() signal
162 return kFALSE;
163}
164
165////////////////////////////////////////////////////////////////////////////////
166/// Add signal handler to system signal handler list.
167
169{
170 if (gSystem && fSignal != (ESignals)-1) {
172 Added(); // emit Added() signal
173 }
174}
175
176////////////////////////////////////////////////////////////////////////////////
177/// Remove signal handler from system signal handler list.
178
180{
181 if (gSystem && fSignal != (ESignals)-1) {
183 Removed(); // emit Removed() signal
184 }
185}
186
187
188////////////////////////////////////////////////////////////////////////////////
189/// Handle standard C++ exceptions intercepted by the TSystem::Run().
190///
191/// Virtual method EStatus Handle(std::exception& exc) is called on the
192/// collection of handlers registered to TSystem. The return value of
193/// each handler influences the continuation of handling procedure:
194/// - kSEProceed - Proceed with passing of the exception to other
195/// handlers, the exception has not been handled.
196/// - kSEHandled - The exception has been handled, do not pass it to
197/// other handlers.
198/// - kSEAbort - Abort application.
199/// If all handlers return kSEProceed TSystem::Run() rethrows the
200/// exception, possibly resulting in process abortion.
201
203{
204}
205
206////////////////////////////////////////////////////////////////////////////////
207/// Add std::exception handler to system handler list.
208
210{
211 if (gSystem) {
213 Added(); // emit Added() signal
214 }
215}
216
217////////////////////////////////////////////////////////////////////////////////
218/// Remove std::exception handler from system handler list.
219
221{
222 if (gSystem) {
224 Removed(); // emit Removed() signal
225 }
226}
227
228////////////////////////////////////////////////////////////////////////////////
229/// Notify when signal occurs.
230
232{
233 Notified(); // emit Notified() signal
234 return kFALSE;
235}
int Int_t
Definition: RtypesCore.h:45
const Bool_t kFALSE
Definition: RtypesCore.h:101
bool Bool_t
Definition: RtypesCore.h:63
const Bool_t kTRUE
Definition: RtypesCore.h:100
#define ClassImp(name)
Definition: Rtypes.h:364
ESignals
R__EXTERN TSystem * gSystem
Definition: TSystem.h:559
virtual void SetInterest(Int_t mask)
Set interest mask to 'mask'.
virtual Bool_t Notify()
Notify when event occurred on descriptor associated with this handler.
virtual void Remove()
Remove file event handler from system file handler list.
virtual Bool_t HasReadInterest()
True if handler is interested in read events.
virtual Bool_t WriteNotify()
Notify when something can be written to the descriptor associated with this handler.
virtual Bool_t HasWriteInterest()
True if handler is interested in write events.
virtual Bool_t ReadNotify()
Notify when something can be read from the descriptor associated with this handler.
virtual void Add()
Add file event handler to system file handler list.
virtual void Add()
Add signal handler to system signal handler list.
virtual Bool_t Notify()
Notify when signal occurs.
virtual void Remove()
Remove signal handler from system signal handler list.
TStdExceptionHandler()
Handle standard C++ exceptions intercepted by the TSystem::Run().
virtual void Remove()
Remove std::exception handler from system handler list.
virtual void Add()
Add std::exception handler to system handler list.
virtual Bool_t Notify()
Notify when signal occurs.
Abstract base class for handling system events.
void DeActivate()
De-activate a system event handler.
virtual void Added()
virtual void Notified()
virtual void Removed()
void Activate()
Activate a system event handler.
virtual void DeActivated()
virtual void Activated()
virtual void AddFileHandler(TFileHandler *fh)
Add a file handler to the list of system file handlers.
Definition: TSystem.cxx:557
virtual TStdExceptionHandler * RemoveStdExceptionHandler(TStdExceptionHandler *eh)
Remove an exception handler from list of exception handlers.
Definition: TSystem.cxx:624
virtual TFileHandler * RemoveFileHandler(TFileHandler *fh)
Remove a file handler from the list of file handlers.
Definition: TSystem.cxx:567
virtual void AddSignalHandler(TSignalHandler *sh)
Add a signal handler to list of system signal handlers.
Definition: TSystem.cxx:535
virtual void AddStdExceptionHandler(TStdExceptionHandler *eh)
Add an exception handler to list of system exception handlers.
Definition: TSystem.cxx:614
virtual TSignalHandler * RemoveSignalHandler(TSignalHandler *sh)
Remove a signal handler from list of signal handlers.
Definition: TSystem.cxx:545