mpd/src/event/PollGroupPoll.cxx
2016-02-26 17:54:05 +01:00

90 lines
2.3 KiB
C++

/*
* Copyright 2003-2016 The Music Player Daemon Project
* http://www.musicpd.org
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#include "config.h"
#ifdef USE_POLL
#include "PollGroupPoll.hxx"
#include <assert.h>
PollGroupPoll::PollGroupPoll() { }
PollGroupPoll::~PollGroupPoll() { }
bool PollGroupPoll::Add(int fd, unsigned events, void *obj)
{
assert(items.find(fd) == items.end());
const size_t index = poll_events.size();
poll_events.resize(index + 1);
auto &e = poll_events[index];
e.fd = fd;
e.events = events;
e.revents = 0;
auto &item = items[fd];
item.index = index;
item.obj = obj;
return true;
}
bool PollGroupPoll::Modify(int fd, unsigned events, void *obj)
{
auto item_iter = items.find(fd);
assert(item_iter != items.end());
auto &item = item_iter->second;
item.obj = obj;
auto &e = poll_events[item.index];
e.events = events;
e.revents &= events;
return true;
}
bool PollGroupPoll::Remove(int fd)
{
auto item_iter = items.find(fd);
assert(item_iter != items.end());
auto &item = item_iter->second;
size_t index = item.index;
size_t last_index = poll_events.size() - 1;
if (index != last_index) {
std::swap(poll_events[index], poll_events[last_index]);
items[poll_events[index].fd].index = index;
}
poll_events.pop_back();
items.erase(item_iter);
return true;
}
void PollGroupPoll::ReadEvents(PollResultGeneric &result, int timeout_ms)
{
int n = poll(poll_events.empty() ? nullptr : &poll_events[0],
poll_events.size(), timeout_ms);
for (size_t i = 0; n > 0 && i < poll_events.size(); ++i) {
const auto &e = poll_events[i];
if (e.revents != 0) {
result.Add(e.revents, items[e.fd].obj);
--n;
}
}
}
#endif