4 // Fraunhofer Institut fuer offene Kommunikationssysteme (FOKUS)
5 // Kompetenzzentrum fuer Satelitenkommunikation (SatCom)
6 // Stefan Bund <stefan.bund@fokus.fraunhofer.de>
8 // This program is free software; you can redistribute it and/or modify
9 // it under the terms of the GNU General Public License as published by
10 // the Free Software Foundation; either version 2 of the License, or
11 // (at your option) any later version.
13 // This program is distributed in the hope that it will be useful,
14 // but WITHOUT ANY WARRANTY; without even the implied warranty of
15 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 // GNU General Public License for more details.
18 // You should have received a copy of the GNU General Public License
19 // along with this program; if not, write to the
20 // Free Software Foundation, Inc.,
21 // 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
23 // TODO: Implement signal handling
24 // Here a basic concept of how to add signal support to the scheduler:
26 // Every signal to be reported by the scheduler will be asigned a
27 // generic signal handler by the scheduler. This signal handler will
28 // use longjmp (juck) to report this signal back to the scheduler
31 // To make this safe, the main-loop will look something like:
33 // int signal = setjmp(jmpBuffer_);
35 // // unblock all signals which are registered with the
38 // // block all relevant signals again
41 // // now handle the event
43 // The signal handler is then simply defined as
45 // static void Scheduler::sigHandler(int signal)
47 // // make sure to restore the signal handler here if
49 // longjmp(Scheduler::instance().jmpBuffer_,signal);
52 // You should use sigaction to register the signal handlers and define
53 // a sa_mask so all Scheduler-registered signals are automatically
54 // *blocked* whenever one of the signals is called (including the
55 // called signal!). This ensures, that no two signals can be delivered
56 // on top of each other. And of course any signal registered with the
57 // scheduler must be blocked as soon as it is registered with the
60 // TODO: Multithreading support
61 // To support multithreading, the static member Scheduler::instance()
62 // must return a thread-local value (that is Scheduler::instance()
63 // must allocate one Scheduler instance per thread)
65 // Definition of non-inline non-template functions
67 #include "Scheduler.hh"
68 //#include "Scheduler.ih"
72 #include <sys/epoll.h>
73 #include "Utils/Exception.hh"
75 static const int EPollInitialSize = 16;
78 ///////////////////////////////cc.p////////////////////////////////////////
80 prefix_ satcom::lib::Scheduler::Scheduler & satcom::lib::Scheduler::instance()
82 static Scheduler instance;
86 prefix_ satcom::lib::Scheduler::Scheduler()
87 : epollFd_(epoll_create(EPollInitialSize))
90 throw SystemException(errno);
93 prefix_ void satcom::lib::Scheduler::add(int fd, Callback const & cb, EventId eventMask)
95 FdTable::iterator i (fdTable_.find(fd));
96 int action (EPOLL_CTL_MOD);
97 if (i == fdTable_.end()) {
98 action = EPOLL_CTL_ADD;
99 i = fdTable_.insert(std::make_pair(fd, EventSpec())).first;
102 if (eventMask & EV_READ) i->second.cb_read = cb;
103 if (eventMask & EV_PRIO) i->second.cb_prio = cb;
104 if (eventMask & EV_WRITE) i->second.cb_write = cb;
105 if (eventMask & EV_HUP) i->second.cb_hup = cb;
106 if (eventMask & EV_ERR) i->second.cb_err = cb;
109 memset(&ev,0,sizeof(ev));
110 ev.events = i->second.epollMask();
113 if (epoll_ctl(epollFd_, action, fd, &ev)<0)
114 throw SystemException(errno);
117 prefix_ void satcom::lib::Scheduler::remove(int fd, EventId eventMask)
119 FdTable::iterator i (fdTable_.find(fd));
120 if (i == fdTable_.end())
123 if (eventMask & EV_READ) i->second.cb_read = 0;
124 if (eventMask & EV_PRIO) i->second.cb_prio = 0;
125 if (eventMask & EV_WRITE) i->second.cb_write = 0;
126 if (eventMask & EV_HUP) i->second.cb_hup = 0;
127 if (eventMask & EV_ERR) i->second.cb_err = 0;
130 memset(&ev,0,sizeof(ev));
131 ev.events = i->second.epollMask();
134 int action (EPOLL_CTL_MOD);
136 action = EPOLL_CTL_DEL;
140 if (epoll_ctl(epollFd_, action, fd, &ev)<0)
141 throw SystemException(errno);
144 prefix_ int satcom::lib::Scheduler::EventSpec::epollMask()
148 if (cb_read) mask |= EPOLLIN;
149 if (cb_prio) mask |= EPOLLPRI;
150 if (cb_write) mask |= EPOLLOUT;
151 if (cb_hup) mask |= EPOLLHUP;
152 if (cb_err) mask |= EPOLLERR;
156 prefix_ void satcom::lib::Scheduler::process()
159 while (! terminate_) {
160 struct epoll_event ev;
161 int events = epoll_wait(epollFd_, &ev, 1, 1000);
163 // Hmm ... man epoll says, it will NOT return with EINTR ??
164 throw SystemException(errno);
168 FdTable::iterator i = fdTable_.find(ev.data.fd);
169 BOOST_ASSERT (i != fdTable_.end() );
170 EventSpec const & spec (i->second);
172 if (ev.events & EPOLLIN) {
173 BOOST_ASSERT(spec.cb_read);
174 spec.cb_read(ev.data.fd, EV_READ);
176 else if (ev.events & EPOLLPRI) {
177 BOOST_ASSERT(spec.cb_prio);
178 spec.cb_prio (ev.data.fd, EV_PRIO);
180 else if (ev.events & EPOLLOUT) {
181 BOOST_ASSERT(spec.cb_write);
182 spec.cb_write(ev.data.fd, EV_WRITE);
185 else if (ev.events & EPOLLHUP) {
186 BOOST_ASSERT(spec.cb_hup);
187 spec.cb_hup(ev.data.fd, EV_HUP);
189 else if (ev.events & EPOLLERR) {
190 BOOST_ASSERT(spec.cb_err);
191 spec.cb_err(ev.data.fd, EV_ERR);
196 ///////////////////////////////cc.e////////////////////////////////////////
202 // c-file-style: "satcom"