forked from premiere/premiere-libtorrent
142 lines
4.0 KiB
C++
142 lines
4.0 KiB
C++
/*
|
|
|
|
Copyright (c) 2013-2016, Arvid Norberg
|
|
All rights reserved.
|
|
|
|
Redistribution and use in source and binary forms, with or without
|
|
modification, are permitted provided that the following conditions
|
|
are met:
|
|
|
|
* Redistributions of source code must retain the above copyright
|
|
notice, this list of conditions and the following disclaimer.
|
|
* Redistributions in binary form must reproduce the above copyright
|
|
notice, this list of conditions and the following disclaimer in
|
|
the documentation and/or other materials provided with the distribution.
|
|
* Neither the name of the author nor the names of its
|
|
contributors may be used to endorse or promote products derived
|
|
from this software without specific prior written permission.
|
|
|
|
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
|
|
AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|
ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
|
|
LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
|
|
CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
|
|
SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
|
|
INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
|
|
CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
|
|
ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
|
|
POSSIBILITY OF SUCH DAMAGE.
|
|
|
|
*/
|
|
|
|
#include "libtorrent/resolver.hpp"
|
|
#include <boost/bind.hpp>
|
|
#include "libtorrent/debug.hpp"
|
|
#include "libtorrent/aux_/time.hpp"
|
|
|
|
namespace libtorrent
|
|
{
|
|
resolver::resolver(io_service& ios)
|
|
: m_ios(ios)
|
|
, m_resolver(ios)
|
|
, m_critical_resolver(ios)
|
|
, m_max_size(700)
|
|
, m_timeout(seconds(1200))
|
|
{}
|
|
|
|
void resolver::on_lookup(error_code const& ec, tcp::resolver::iterator i
|
|
, resolver_interface::callback_t h, std::string hostname)
|
|
{
|
|
#if defined TORRENT_ASIO_DEBUGGING
|
|
complete_async("resolver::on_lookup");
|
|
#endif
|
|
if (ec)
|
|
{
|
|
std::vector<address> empty;
|
|
h(ec, empty);
|
|
return;
|
|
}
|
|
|
|
dns_cache_entry& ce = m_cache[hostname];
|
|
time_point now = aux::time_now();
|
|
ce.last_seen = now;
|
|
ce.addresses.clear();
|
|
while (i != tcp::resolver::iterator())
|
|
{
|
|
ce.addresses.push_back(i->endpoint().address());
|
|
++i;
|
|
}
|
|
|
|
h(ec, ce.addresses);
|
|
|
|
// if m_cache grows too big, weed out the
|
|
// oldest entries
|
|
if (m_cache.size() > m_max_size)
|
|
{
|
|
cache_t::iterator oldest = m_cache.begin();
|
|
for (cache_t::iterator k = m_cache.begin();
|
|
k != m_cache.end(); ++k)
|
|
{
|
|
if (k->second.last_seen < oldest->second.last_seen)
|
|
oldest = k;
|
|
}
|
|
|
|
// remove the oldest entry
|
|
m_cache.erase(oldest);
|
|
}
|
|
}
|
|
|
|
void resolver::async_resolve(std::string const& host, int flags
|
|
, resolver_interface::callback_t const& h)
|
|
{
|
|
cache_t::iterator i = m_cache.find(host);
|
|
if (i != m_cache.end())
|
|
{
|
|
// keep cache entries valid for m_timeout seconds
|
|
if ((flags & resolver_interface::prefer_cache)
|
|
|| i->second.last_seen + m_timeout >= aux::time_now())
|
|
{
|
|
error_code ec;
|
|
m_ios.post(boost::bind(h, ec, i->second.addresses));
|
|
return;
|
|
}
|
|
}
|
|
|
|
// special handling for raw IP addresses. There's no need to get in line
|
|
// behind actual lookups if we can just resolve it immediately.
|
|
error_code ec;
|
|
address ip = address::from_string(host.c_str(), ec);
|
|
if (!ec)
|
|
{
|
|
std::vector<address> addresses;
|
|
addresses.push_back(ip);
|
|
m_ios.post(boost::bind(h, ec, addresses));
|
|
return;
|
|
}
|
|
|
|
// the port is ignored
|
|
tcp::resolver::query q(host, "80");
|
|
|
|
#if defined TORRENT_ASIO_DEBUGGING
|
|
add_outstanding_async("resolver::on_lookup");
|
|
#endif
|
|
if (flags & resolver_interface::abort_on_shutdown)
|
|
{
|
|
m_resolver.async_resolve(q, boost::bind(&resolver::on_lookup, this, _1, _2
|
|
, h, host));
|
|
}
|
|
else
|
|
{
|
|
m_critical_resolver.async_resolve(q, boost::bind(&resolver::on_lookup, this, _1, _2
|
|
, h, host));
|
|
}
|
|
}
|
|
|
|
void resolver::abort()
|
|
{
|
|
m_resolver.cancel();
|
|
}
|
|
}
|
|
|