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#ifndef QPID_SYS_LINUX_POLLABLECONDITION_CPP
#define QPID_SYS_LINUX_POLLABLECONDITION_CPP
/*
*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*
*/
// FIXME aconway 2008-08-11: this could be of more general interest,
// move to common lib.
//
#include "PollableCondition.h"
#include "qpid/sys/posix/PrivatePosix.h"
#include "qpid/Exception.h"
#include <unistd.h>
#include <fcntl.h>
namespace qpid {
namespace sys {
PollableCondition::PollableCondition() : IOHandle(new sys::IOHandlePrivate) {
int fds[2];
if (::pipe(fds) == -1)
throw ErrnoException(QPID_MSG("Can't create PollableCondition"));
impl->fd = fds[0];
writeFd = fds[1];
if (::fcntl(impl->fd, F_SETFL, O_NONBLOCK) == -1)
throw ErrnoException(QPID_MSG("Can't create PollableCondition"));
if (::fcntl(writeFd, F_SETFL, O_NONBLOCK) == -1)
throw ErrnoException(QPID_MSG("Can't create PollableCondition"));
}
bool PollableCondition::clear() {
char buf[256];
ssize_t n;
bool wasSet = false;
while ((n = ::read(impl->fd, buf, sizeof(buf))) > 0)
wasSet = true;
if (n == -1 && errno != EAGAIN) throw ErrnoException(QPID_MSG("Error clearing PollableCondition"));
return wasSet;
}
void PollableCondition::set() {
static const char dummy=0;
ssize_t n = ::write(writeFd, &dummy, 1);
if (n == -1 && errno != EAGAIN) throw ErrnoException("Error setting PollableCondition");
}
#if 0
// FIXME aconway 2008-08-12: More efficient Linux implementation using
// eventfd system call. Move to separate file & do configure.ac test
// to enable this when ::eventfd() is available.
#include <sys/eventfd.h>
namespace qpid {
namespace sys {
PollableCondition::PollableCondition() : IOHandle(new sys::IOHandlePrivate) {
impl->fd = ::eventfd(0, 0);
if (impl->fd < 0) throw ErrnoException("conditionfd() failed");
}
bool PollableCondition::clear() {
char buf[8];
ssize_t n = ::read(impl->fd, buf, 8);
if (n != 8) throw ErrnoException("read failed on conditionfd");
return *reinterpret_cast<uint64_t*>(buf);
}
void PollableCondition::set() {
static const uint64_t value=1;
ssize_t n = ::write(impl->fd, reinterpret_cast<const void*>(&value), 8);
if (n != 8) throw ErrnoException("write failed on conditionfd");
}
#endif
}} // namespace qpid::sys
#endif /*!QPID_SYS_LINUX_POLLABLECONDITION_CPP*/
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