/* -*- compile-command: "make -k -j3"; -*- */ /* * Copyright 2010-2013 by Eric House (xwords@eehouse.org). All rights * reserved. * * 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ #include #include "udpqueue.h" #include "mlock.h" static UdpQueue* s_instance = NULL; void PacketThreadClosure::logStats() { time_t now = time( NULL ); if ( 1 < now - m_created ) { logf( XW_LOGERROR, "packet %d waited %d s for processing which then took %d s", getID(), m_dequed - m_created, now - m_dequed ); } } bool PartialPacket::stillGood() const { return 0 == m_errno || EAGAIN == m_errno || EWOULDBLOCK == m_errno; } bool PartialPacket::readAtMost( int len ) { assert( len > 0 ); bool success = false; uint8_t tmp[len]; ssize_t nRead = recv( m_sock, tmp, len, 0 ); if ( 0 > nRead ) { // error case m_errno = errno; if ( !stillGood() ) { logf( XW_LOGERROR, "%s(len=%d, socket=%d): recv failed: %d (%s)", __func__, len, m_sock, m_errno, strerror(m_errno) ); } } else if ( 0 == nRead ) { // remote socket half-closed logf( XW_LOGINFO, "%s(): remote closed (socket=%d)", __func__, m_sock ); m_errno = -1; // so stillGood will fail } else { // logf( XW_LOGVERBOSE0, "%s(): read %d bytes on socket %d", __func__, // nRead, m_sock ); m_errno = 0; success = len == nRead; int curSize = m_buf.size(); m_buf.resize( nRead + curSize ); memcpy( &m_buf[curSize], tmp, nRead ); } return success; } UdpQueue::UdpQueue() { m_nextID = 0; pthread_mutex_init ( &m_partialsMutex, NULL ); pthread_mutex_init ( &m_queueMutex, NULL ); pthread_cond_init( &m_queueCondVar, NULL ); pthread_t thread; int result = pthread_create( &thread, NULL, thread_main_static, this ); assert( result == 0 ); result = pthread_detach( thread ); assert( result == 0 ); } UdpQueue::~UdpQueue() { pthread_cond_destroy( &m_queueCondVar ); pthread_mutex_destroy ( &m_queueMutex ); pthread_mutex_destroy ( &m_partialsMutex ); } UdpQueue* UdpQueue::get() { if ( s_instance == NULL ) { s_instance = new UdpQueue(); } return s_instance; } // If we're already assembling data from this socket, continue. Otherwise // create a new parital packet and store data there. If we wind up with a // complete packet, dispatch it and delete since the data's been delivered. // // Return false if socket should no longer be used. bool UdpQueue::handle( const AddrInfo* addr, QueueCallback cb ) { assert( addr->isTCP() ); PartialPacket* packet; bool success = true; int sock = addr->getSocket(); // Hang onto this mutex for as long as we may be writing to the packet // since having it deleted while in use would be bad. MutexLock ml( &m_partialsMutex ); map::iterator iter = m_partialPackets.find( sock ); if ( m_partialPackets.end() == iter ) { packet = new PartialPacket( sock ); m_partialPackets.insert( pair( sock, packet ) ); } else { packet = iter->second; } // First see if we've read the length bytes if ( packet->readSoFar() < sizeof( packet->m_len ) ) { if ( packet->readAtMost( sizeof(packet->m_len) - packet->readSoFar() ) ) { uint16_t tmp; memcpy( &tmp, packet->data(), sizeof(tmp) ); packet->m_len = ntohs(tmp); success = 0 < packet->m_len; } } if ( success && packet->readSoFar() >= sizeof( packet->m_len ) ) { assert( 0 < packet->m_len ); int leftToRead = packet->m_len - (packet->readSoFar() - sizeof(packet->m_len)); if ( packet->readAtMost( leftToRead ) ) { handle( addr, packet->data() + sizeof(packet->m_len), packet->m_len, cb ); packet = NULL; newSocket_locked( sock ); } } success = success && (NULL == packet || packet->stillGood()); logf( XW_LOGVERBOSE0, "%s(sock=%d) => %d", __func__, sock, success ); return success; } void UdpQueue::handle( const AddrInfo* addr, const uint8_t* buf, int len, QueueCallback cb ) { // addr->ref(); PacketThreadClosure* ptc = new PacketThreadClosure( addr, buf, len, cb ); MutexLock ml( &m_queueMutex ); int id = ++m_nextID; ptc->setID( id ); logf( XW_LOGINFO, "%s(): enqueuing packet %d (socket %d, len %d)", __func__, id, addr->getSocket(), len ); m_queue.push_back( ptc ); pthread_cond_signal( &m_queueCondVar ); } // Remove any PartialPacket record with the same socket/fd. This makes sense // when the socket's being reused or when we have just dealt with a single // packet and might be getting more. void UdpQueue::newSocket_locked( int sock ) { map::iterator iter = m_partialPackets.find( sock ); if ( m_partialPackets.end() != iter ) { delete iter->second; m_partialPackets.erase( iter ); } } void UdpQueue::newSocket( int sock ) { MutexLock ml( &m_partialsMutex ); newSocket_locked( sock ); } void UdpQueue::newSocket( const AddrInfo* addr ) { assert( addr->isTCP() ); newSocket( addr->getSocket() ); } void* UdpQueue::thread_main() { for ( ; ; ) { pthread_mutex_lock( &m_queueMutex ); while ( m_queue.size() == 0 ) { pthread_cond_wait( &m_queueCondVar, &m_queueMutex ); } PacketThreadClosure* ptc = m_queue.front(); m_queue.pop_front(); pthread_mutex_unlock( &m_queueMutex ); ptc->noteDequeued(); time_t age = ptc->ageInSeconds(); if ( 30 > age ) { logf( XW_LOGINFO, "%s: dispatching packet %d (socket %d); " "%d seconds old", __func__, ptc->getID(), ptc->addr()->getSocket(), age ); (*ptc->cb())( ptc ); ptc->logStats(); } else { logf( XW_LOGINFO, "%s: dropping packet %d; it's %d seconds old!", __func__, age ); } // ptc->addr()->unref(); delete ptc; } return NULL; } /* static */ void* UdpQueue::thread_main_static( void* closure ) { blockSignals(); UdpQueue* me = (UdpQueue*)closure; return me->thread_main(); }