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"
74 #include "Utils/MicroTime.hh"
76 static const int EPollInitialSize = 16;
79 ///////////////////////////////cc.p////////////////////////////////////////
81 prefix_ satcom::lib::Scheduler::Scheduler & satcom::lib::Scheduler::instance()
83 static Scheduler instance;
87 prefix_ void satcom::lib::Scheduler::timeout(unsigned long timeout, TimerCallback const & cb)
89 timerQueue_.push(TimerSpec(now()+1000*timeout,cb));
92 prefix_ satcom::lib::Scheduler::Scheduler()
93 : epollFd_(epoll_create(EPollInitialSize))
96 throw SystemException(errno);
99 prefix_ void satcom::lib::Scheduler::do_add(int fd, SimpleCallback const & cb, int eventMask)
101 FdTable::iterator i (fdTable_.find(fd));
102 int action (EPOLL_CTL_MOD);
103 if (i == fdTable_.end()) {
104 action = EPOLL_CTL_ADD;
105 i = fdTable_.insert(std::make_pair(fd, EventSpec())).first;
108 if (eventMask & EV_READ) i->second.cb_read = cb;
109 if (eventMask & EV_PRIO) i->second.cb_prio = cb;
110 if (eventMask & EV_WRITE) i->second.cb_write = cb;
111 if (eventMask & EV_HUP) i->second.cb_hup = cb;
112 if (eventMask & EV_ERR) i->second.cb_err = cb;
115 memset(&ev,0,sizeof(ev));
116 ev.events = i->second.epollMask();
119 if (epoll_ctl(epollFd_, action, fd, &ev)<0)
120 throw SystemException(errno);
123 prefix_ void satcom::lib::Scheduler::do_remove(int fd, int eventMask)
125 FdTable::iterator i (fdTable_.find(fd));
126 if (i == fdTable_.end())
129 if (eventMask & EV_READ) i->second.cb_read = 0;
130 if (eventMask & EV_PRIO) i->second.cb_prio = 0;
131 if (eventMask & EV_WRITE) i->second.cb_write = 0;
132 if (eventMask & EV_HUP) i->second.cb_hup = 0;
133 if (eventMask & EV_ERR) i->second.cb_err = 0;
136 memset(&ev,0,sizeof(ev));
137 ev.events = i->second.epollMask();
140 int action (EPOLL_CTL_MOD);
142 action = EPOLL_CTL_DEL;
146 if (epoll_ctl(epollFd_, action, fd, &ev)<0)
147 throw SystemException(errno);
151 prefix_ int satcom::lib::Scheduler::EventSpec::epollMask()
155 if (cb_read) mask |= EPOLLIN;
156 if (cb_prio) mask |= EPOLLPRI;
157 if (cb_write) mask |= EPOLLOUT;
158 if (cb_hup) mask |= EPOLLHUP;
159 if (cb_err) mask |= EPOLLERR;
163 prefix_ void satcom::lib::Scheduler::process()
166 while (! terminate_) {
168 MicroTime timeNow = now();
169 while ( ! timerQueue_.empty() && timerQueue_.top().timeout <= timeNow ) {
170 timerQueue_.top().cb();
175 int timeout = timerQueue_.empty() ? -1 : int((timerQueue_.top().timeout - timeNow)/1000);
177 struct epoll_event ev;
178 int events = epoll_wait(epollFd_, &ev, 1, timeout);
180 // Hmm ... man epoll says, it will NOT return with EINTR ??
181 throw SystemException(errno);
183 // Timeout .. it will be run when reachiung the top of the loop
186 FdTable::iterator i = fdTable_.find(ev.data.fd);
187 BOOST_ASSERT (i != fdTable_.end() );
188 EventSpec const & spec (i->second);
190 if (ev.events & EPOLLIN) {
191 BOOST_ASSERT(spec.cb_read);
192 spec.cb_read(EV_READ);
194 else if (ev.events & EPOLLPRI) {
195 BOOST_ASSERT(spec.cb_prio);
196 spec.cb_prio(EV_PRIO);
198 else if (ev.events & EPOLLOUT) {
199 BOOST_ASSERT(spec.cb_write);
200 spec.cb_write(EV_WRITE);
203 else if (ev.events & EPOLLHUP) {
206 else if (ev.events & EPOLLERR) {
207 if (spec.cb_write) spec.cb_write(EV_HUP);
208 if (spec.cb_read) spec.cb_read(EV_HUP);
211 else if (ev.events & EPOLLERR && ! ev.events & EPOLLHUP) {
215 if (spec.cb_write) spec.cb_write(EV_ERR);
216 if (spec.cb_read) spec.cb_read(EV_ERR);
223 ///////////////////////////////cc.e////////////////////////////////////////
229 // c-file-style: "satcom"