/*
* Created on Jul 28, 2004
* Created by Alon Rohter
* Copyright (C) 2004, 2005, 2006 Aelitis, 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.
*
* AELITIS, SAS au capital de 46,603.30 euros
* 8 Allee Lenotre, La Grille Royale, 78600 Le Mesnil le Roi, France.
*
*/
package com.aelitis.azureus.core.networkmanager.impl.tcp;
import java.nio.channels.*;
import java.nio.channels.spi.AbstractSelectableChannel;
import java.util.*;
import org.gudy.azureus2.core3.logging.*;
import org.gudy.azureus2.core3.util.*;
import com.aelitis.azureus.core.networkmanager.VirtualChannelSelector;
/**
* Provides a simplified and safe (selectable-channel) socket single-op selector.
*/
public class VirtualChannelSelectorImpl {
private static final LogIDs LOGID = LogIDs.NWMAN;
private static final boolean MAYBE_BROKEN_SELECT;
static{
// freebsd 7.x and diablo 1.6 no works as selector returns none ready even though
// there's a bunch readable
// Seems to not just be diablo java, but general 7.1 problem
String jvm_name = System.getProperty( "java.vm.name", "" );
boolean is_diablo = jvm_name.startsWith( "Diablo" );
boolean is_freebsd_7_or_higher = false;
// hack for 10.6 - will switch to not doing System.setProperty( "java.nio.preferSelect", "true" ); later
boolean is_osx_16 = false;
try{
// unfortunately the package maintainer has set os.name to Linux for FreeBSD...
if ( Constants.isFreeBSD || Constants.isLinux ){
String os_type = System.getenv( "OSTYPE" );
if ( os_type != null && os_type.equals( "FreeBSD" )){
String os_version = System.getProperty( "os.version", "" );
String digits = "";
for ( int i=0;i<os_version.length();i++){
char c = os_version.charAt(i);
if ( Character.isDigit(c)){
digits += c;
}else{
break;
}
}
if ( digits.length() > 0 ){
is_freebsd_7_or_higher = Integer.parseInt(digits) >= 7;
}
}
}else if ( Constants.isOSX ){
String os_version = System.getProperty( "os.version", "" );
if ( os_version.startsWith( "10.6" )){
is_osx_16 = true;
}
}
}catch( Throwable e ){
e.printStackTrace();
}
MAYBE_BROKEN_SELECT = is_freebsd_7_or_higher || is_diablo || is_osx_16;
if ( MAYBE_BROKEN_SELECT ){
System.out.println( "Enabling broken select detection: diablo=" + is_diablo + ", freebsd 7+=" + is_freebsd_7_or_higher + ", osx 10.6=" + is_osx_16 );
}
}
private boolean select_is_broken;
private int select_looks_broken_count;
private boolean logged_broken_select;
/*
static boolean rm_trace = false;
static boolean rm_test_fix = false;
static{
COConfigurationManager.addAndFireParameterListeners(
new String[]{ "user.rm.trace", "user.rm.testfix" },
new ParameterListener()
{
public void
parameterChanged(
String parameterName)
{
rm_trace = COConfigurationManager.getBooleanParameter( "user.rm.trace", false );
rm_test_fix = COConfigurationManager.getBooleanParameter( "user.rm.testfix", false );
}
});
}
private long rm_flag_last_log;
private Map rm_listener_map = new HashMap();
*/
protected Selector selector;
private final SelectorGuard selector_guard;
private final LinkedList<Object> register_cancel_list = new LinkedList<Object>();
private final AEMonitor register_cancel_list_mon = new AEMonitor( "VirtualChannelSelector:RCL");
private final HashMap<AbstractSelectableChannel, Boolean> paused_states = new HashMap<AbstractSelectableChannel, Boolean>();
private final int INTEREST_OP;
private final boolean pause_after_select;
protected final VirtualChannelSelector parent;
//private int[] select_counts = new int[ 50 ];
//private int round = 0;
private volatile boolean destroyed;
private boolean randomise_keys;
private int next_select_loop_pos = 0;
private static final int WRITE_SELECTOR_DEBUG_CHECK_PERIOD = 10000;
private static final int WRITE_SELECTOR_DEBUG_MAX_TIME = 20000;
private long last_write_select_debug;
private long last_select_debug;
public VirtualChannelSelectorImpl( VirtualChannelSelector _parent, int _interest_op, boolean _pause_after_select, boolean _randomise_keys ) {
this.parent = _parent;
INTEREST_OP = _interest_op;
pause_after_select = _pause_after_select;
randomise_keys = _randomise_keys;
String type;
switch( INTEREST_OP ) {
case VirtualChannelSelector.OP_CONNECT:
type = "OP_CONNECT"; break;
case VirtualChannelSelector.OP_READ:
type = "OP_READ"; break;
default:
type = "OP_WRITE"; break;
}
selector_guard = new SelectorGuard( type, new SelectorGuard.GuardListener() {
public boolean safeModeSelectEnabled() {
return parent.isSafeSelectionModeEnabled();
}
public void spinDetected() {
closeExistingSelector();
try { Thread.sleep( 1000 ); }catch( Throwable x ) {x.printStackTrace();}
parent.enableSafeSelectionMode();
}
public void failureDetected() {
try { Thread.sleep( 10000 ); }catch( Throwable x ) {x.printStackTrace();}
closeExistingSelector();
try { Thread.sleep( 1000 ); }catch( Throwable x ) {x.printStackTrace();}
selector = openNewSelector();
}
});
selector = openNewSelector();
}
protected Selector openNewSelector() {
Selector sel = null;
try {
sel = Selector.open();
AEDiagnostics.logWithStack( "seltrace", "Selector created for '" + parent.getName() + "'," + selector_guard.getType());
}
catch (Throwable t) {
Debug.out( "ERROR: caught exception on Selector.open()", t );
try { Thread.sleep( 3000 ); }catch( Throwable x ) {x.printStackTrace();}
int fail_count = 1;
while( fail_count < 10 ) {
try {
sel = Selector.open();
AEDiagnostics.logWithStack( "seltrace", "Selector created for '" + parent.getName() + "'," + selector_guard.getType());
break;
}
catch( Throwable f ) {
Debug.out( f );
fail_count++;
try { Thread.sleep( 3000 ); }catch( Throwable x ) {x.printStackTrace();}
}
}
if( fail_count < 10 ) { //success !
Debug.out( "NOTICE: socket Selector successfully opened after " +fail_count+ " failures." );
}
else { //failure
Logger.log(new LogAlert(LogAlert.REPEATABLE, LogAlert.AT_ERROR,
"ERROR: socket Selector.open() failed 10 times in a row, aborting."
+ "\nAzureus / Java is likely being firewalled!"));
}
}
return sel;
}
public void
setRandomiseKeys(
boolean r )
{
randomise_keys = r;
}
public void pauseSelects( AbstractSelectableChannel channel ) {
//System.out.println( "pauseSelects: " + channel + " - " + Debug.getCompressedStackTrace() );
if( channel == null ) {
return;
}
SelectionKey key = channel.keyFor( selector );
if( key != null && key.isValid() ) {
key.interestOps( key.interestOps() & ~INTEREST_OP );
}
else { //channel not (yet?) registered
if( channel.isOpen() ) { //only bother if channel has not already been closed
try{ register_cancel_list_mon.enter();
paused_states.put( channel, new Boolean( true ) ); //ensure the op is paused upon reg select-time reg
}
finally{ register_cancel_list_mon.exit(); }
}
}
}
public void resumeSelects( AbstractSelectableChannel channel ) {
//System.out.println( "resumeSelects: " + channel + " - " + Debug.getCompressedStackTrace() );
if( channel == null ) {
Debug.printStackTrace( new Exception( "resumeSelects():: channel == null" ) );
return;
}
SelectionKey key = channel.keyFor( selector );
if( key != null && key.isValid() ) {
// if we're resuming a non-interested key then reset the metrics
if (( key.interestOps() & INTEREST_OP ) == 0 ){
RegistrationData data = (RegistrationData)key.attachment();
data.last_select_success_time = SystemTime.getCurrentTime();
data.non_progress_count = 0;
}
key.interestOps( key.interestOps() | INTEREST_OP );
}
else { //channel not (yet?) registered
try{ register_cancel_list_mon.enter();
paused_states.remove( channel ); //check if the channel's op has been already paused before select-time reg
}
finally{ register_cancel_list_mon.exit(); }
}
//try{
// selector.wakeup();
//}
//catch( Throwable t ) { Debug.out( "selector.wakeup():: caught exception: ", t ); }
}
public void
cancel(
AbstractSelectableChannel channel )
{
//System.out.println( "cancel: " + channel + " - " + Debug.getCompressedStackTrace() );
if ( destroyed ){
// don't worry too much about cancels
}
if ( channel == null ){
Debug.out( "Attempt to cancel selects for null channel" );
return;
}
try{
register_cancel_list_mon.enter();
// ensure that there's only one operation outstanding for a given channel
// at any one time (the latest operation requested )
for (Iterator<Object> it = register_cancel_list.iterator();it.hasNext();){
Object obj = it.next();
if ( channel == obj ||
( obj instanceof RegistrationData &&
((RegistrationData)obj).channel == channel )){
// remove existing cancel or register
it.remove();
break;
}
}
pauseSelects((AbstractSelectableChannel)channel );
register_cancel_list.add( channel );
}finally{
register_cancel_list_mon.exit();
}
}
public void
register(
AbstractSelectableChannel channel,
VirtualChannelSelector.VirtualAbstractSelectorListener listener,
Object attachment )
{
if ( destroyed ){
Debug.out( "register called after selector destroyed" );
}
if ( channel == null ){
Debug.out( "Attempt to register selects for null channel" );
return;
}
try{
register_cancel_list_mon.enter();
// ensure that there's only one operation outstanding for a given channel
// at any one time (the latest operation requested )
for (Iterator<Object> it = register_cancel_list.iterator();it.hasNext();){
Object obj = it.next();
if ( channel == obj ||
( obj instanceof RegistrationData &&
((RegistrationData)obj).channel == channel )){
it.remove();
break;
}
}
paused_states.remove( channel );
register_cancel_list.add( new RegistrationData( channel, listener, attachment ));
}finally{
register_cancel_list_mon.exit();
}
}
public int select( long timeout ) {
long select_start_time = SystemTime.getCurrentTime();
if( selector == null ) {
Debug.out( "VirtualChannelSelector.select() op called with null selector" );
try { Thread.sleep( 3000 ); }catch( Throwable x ) {x.printStackTrace();}
return 0;
}
if( !selector.isOpen()) {
Debug.out( "VirtualChannelSelector.select() op called with closed selector" );
try { Thread.sleep( 3000 ); }catch( Throwable x ) {x.printStackTrace();}
return 0;
}
// store these when they occur so they can be raised *outside* of the monitor to avoid
// potential deadlocks
RegistrationData select_fail_data = null;
Throwable select_fail_excep = null;
//process cancellations
try {
register_cancel_list_mon.enter();
// don't use an iterator here as it is possible that error notifications to listeners
// can result in the addition of a cancel request.
// Note that this can only happen for registrations, and this *should* only result in
// possibly a cancel being added (i.e. not a further registration), hence this can't
// loop. Also note the approach of removing the entry before processing. This is so
// that the logic used when adding a cancel (the removal of any matching entries) does
// not cause the entry we're processing to be removed
while( register_cancel_list.size() > 0 ){
Object obj = register_cancel_list.remove(0);
if ( obj instanceof AbstractSelectableChannel ){
// process cancellation
AbstractSelectableChannel canceled_channel = (AbstractSelectableChannel)obj;
try{
SelectionKey key = canceled_channel.keyFor( selector );
if( key != null ){
key.cancel(); //cancel the key, since already registered
}
}catch( Throwable e ){
Debug.printStackTrace(e);
}
}else{
//process new registrations
RegistrationData data = (RegistrationData)obj;
if( data == null ) {
Debug.out( "data == null" );
}
else if( data.channel == null ) {
Debug.out( "data.channel == null" );
}
try {
if( data.channel.isOpen() ){
// see if already registered
SelectionKey key = data.channel.keyFor( selector );
if ( key != null && key.isValid() ) { //already registered
key.attach( data );
key.interestOps( key.interestOps() | INTEREST_OP ); //ensure op is enabled
}
else{
data.channel.register( selector, INTEREST_OP, data );
}
//check if op has been paused before registration moment
Object paused = paused_states.get( data.channel );
if( paused != null ) {
pauseSelects( data.channel ); //pause it
}
}
else{
select_fail_data = data;
select_fail_excep = new Throwable( "select registration: channel is closed" );
}
}catch (Throwable t){
Debug.printStackTrace(t);
select_fail_data = data;
select_fail_excep = t;
}
}
}
paused_states.clear(); //reset after every registration round
}finally {
register_cancel_list_mon.exit();
}
if ( select_fail_data != null ){
try{
parent.selectFailure(
select_fail_data.listener,
select_fail_data.channel,
select_fail_data.attachment,
select_fail_excep );
}catch( Throwable e ){
Debug.printStackTrace( e );
}
}
//do the actual select
int count = 0;
selector_guard.markPreSelectTime();
try {
count = selector.select( timeout );
}
catch (Throwable t) {
long now = SystemTime.getCurrentTime();
if ( last_select_debug > now || now - last_select_debug > 5000 ){
last_select_debug = now;
String msg = t.getMessage();
if ( msg == null || !msg.equalsIgnoreCase( "bad file descriptor" )){
Debug.out( "Caught exception on selector.select() op: " +msg, t );
}
}
try { Thread.sleep( timeout ); }catch(Throwable e) { e.printStackTrace(); }
}
// do this after the select so that any pending cancels (prior to destroy) are processed
// by the selector before we kill it
if ( destroyed ){
closeExistingSelector();
return( 0 );
}
if ( MAYBE_BROKEN_SELECT &&
!select_is_broken &&
( INTEREST_OP == VirtualChannelSelector.OP_READ || INTEREST_OP == VirtualChannelSelector.OP_WRITE )){
if ( selector.selectedKeys().size() == 0 ){
Set<SelectionKey> keys = selector.keys();
for ( SelectionKey key: keys ){
if (( key.readyOps() & INTEREST_OP ) != 0 ){
select_looks_broken_count++;
break;
}
}
if ( select_looks_broken_count >= 5 ){
select_is_broken = true;
if ( !logged_broken_select ){
logged_broken_select = true;
Debug.outNoStack( "Select operation looks broken, trying workaround" );
}
}
}else{
select_looks_broken_count = 0;
}
}
/*
if( INTEREST_OP == VirtualChannelSelector.OP_READ ) { //TODO
select_counts[ round ] = count;
round++;
if( round == select_counts.length ) {
StringBuffer buf = new StringBuffer( select_counts.length * 3 );
buf.append( "select_counts=" );
for( int i=0; i < select_counts.length; i++ ) {
buf.append( select_counts[i] );
buf.append( ' ' );
}
//System.out.println( buf.toString() );
round = 0;
}
}
*/
selector_guard.verifySelectorIntegrity( count, SystemTime.TIME_GRANULARITY_MILLIS /2 );
if( !selector.isOpen() ) return count;
int progress_made_key_count = 0;
int total_key_count = 0;
long now = SystemTime.getCurrentTime();
//notification of ready keys via listener callback
// debug handling for channels stuck pending write select for long periods
Set<SelectionKey> non_selected_keys = null;
if ( INTEREST_OP == VirtualChannelSelector.OP_WRITE ){
if ( now < last_write_select_debug ||
now - last_write_select_debug > WRITE_SELECTOR_DEBUG_CHECK_PERIOD ){
last_write_select_debug = now;
non_selected_keys = new HashSet<SelectionKey>( selector.keys());
}
}
List<SelectionKey> ready_keys;
if ( MAYBE_BROKEN_SELECT && select_is_broken ){
Set<SelectionKey> all_keys = selector.keys();
ready_keys = new ArrayList<SelectionKey>();
for ( SelectionKey key: all_keys ){
if (( key.readyOps() & INTEREST_OP ) != 0 ){
ready_keys.add( key );
}
}
}else{
ready_keys = new ArrayList<SelectionKey>( selector.selectedKeys());
}
boolean randy = randomise_keys;
if ( randy ){
Collections.shuffle( ready_keys );
}
Set<SelectionKey> selected_keys = selector.selectedKeys();
final int ready_key_size = ready_keys.size();;
final int start_pos = next_select_loop_pos++;
final int end_pos = start_pos + ready_key_size;
for ( int i=start_pos; i<end_pos; i++ ){
SelectionKey key = ready_keys.get( i % ready_key_size );
total_key_count++;
selected_keys.remove( key );
RegistrationData data = (RegistrationData)key.attachment();
if ( non_selected_keys != null ){
non_selected_keys.remove( key );
}
data.last_select_success_time = now;
// int rm_type;
if( key.isValid() ) {
if( (key.interestOps() & INTEREST_OP) == 0 ) { //it must have been paused between select and notification
// rm_type = 2;
}else{
if( pause_after_select ) {
try{
key.interestOps( key.interestOps() & ~INTEREST_OP );
}catch( CancelledKeyException e ){
}
}
boolean progress_indicator = parent.selectSuccess( data.listener, data.channel, data.attachment );
if ( progress_indicator ){
// rm_type = 0;
progress_made_key_count++;
data.non_progress_count = 0;
}else{
// rm_type = 1;
data.non_progress_count++;
boolean loopback_connection = false;
if ( INTEREST_OP != VirtualChannelSelector.OP_ACCEPT ){
SocketChannel sc = (SocketChannel)data.channel;
loopback_connection = sc.socket().getInetAddress().isLoopbackAddress();
}
// we get no progress triggers when looping back for transcoding due to
// high CPU usage of xcode process - remove debug spew and be more tolerant
if ( loopback_connection ){
if ( data.non_progress_count == 10000 ){
Debug.out( "No progress for " + data.non_progress_count + ", closing connection" );
try{
data.channel.close();
}catch( Throwable e ){
e.printStackTrace();
}
}
}else{
if ( data.non_progress_count == 10 ||
data.non_progress_count %100 == 0 && data.non_progress_count > 0 ){
Debug.out(
"VirtualChannelSelector: No progress for op " + INTEREST_OP +
": listener = " + data.listener.getClass() +
", count = " + data.non_progress_count +
", socket: open = " + data.channel.isOpen() +
(INTEREST_OP==VirtualChannelSelector.OP_ACCEPT?"":
(", connected = " + ((SocketChannel)data.channel).isConnected())));
if ( data.non_progress_count == 1000 ){
Debug.out( "No progress for " + data.non_progress_count + ", closing connection" );
try{
data.channel.close();
}catch( Throwable e ){
e.printStackTrace();
}
}
}
}
}
}
}else{
// rm_type = 3;
key.cancel();
parent.selectFailure( data.listener, data.channel, data.attachment, new Throwable( "key is invalid" ) );
// can get this if socket has been closed between select and here
}
/*
if ( rm_trace ){
Object rm_key = data.listener.getClass();
int[] rm_count = (int[])rm_listener_map.get( rm_key );
if ( rm_count == null ){
rm_count = new int[]{0,0,0,0};
rm_listener_map.put( rm_key, rm_count );
}
rm_count[rm_type]++;
}
*/
}
if ( non_selected_keys != null ){
for( Iterator<SelectionKey> i = non_selected_keys.iterator(); i.hasNext(); ) {
SelectionKey key = i.next();
RegistrationData data = (RegistrationData)key.attachment();
try{
if (( key.interestOps() & INTEREST_OP) == 0 ) {
continue;
}
}catch( CancelledKeyException e ){
// get quite a few of these exceptions, ignore the key
continue;
}
long stall_time = now - data.last_select_success_time;
if ( stall_time < 0 ){
data.last_select_success_time = now;
}else{
if ( stall_time > WRITE_SELECTOR_DEBUG_MAX_TIME ){
Logger.log(
new LogEvent(LOGID,LogEvent.LT_WARNING,"Write select for " + key.channel() + " stalled for " + stall_time ));
// hack - trigger a dummy write select to see if things are still OK
if( key.isValid() ) {
if( pause_after_select ) {
key.interestOps( key.interestOps() & ~INTEREST_OP );
}
if ( parent.selectSuccess( data.listener, data.channel, data.attachment )){
data.non_progress_count = 0;
}
}else{
key.cancel();
parent.selectFailure( data.listener, data.channel, data.attachment, new Throwable( "key is invalid" ) );
}
}
}
}
}
// if any of the ready keys hasn't made any progress then enforce minimum sleep period to avoid
// spinning
if ( total_key_count == 0 || progress_made_key_count != total_key_count ){
long time_diff = SystemTime.getCurrentTime() - select_start_time;
if( time_diff < timeout && time_diff >= 0 ) { //ensure that it always takes at least 'timeout' time to complete the select op
try { Thread.sleep( timeout - time_diff ); }catch(Throwable e) { e.printStackTrace(); }
}
}else{
/*
if ( rm_test_fix ){
long time_diff = SystemTime.getCurrentTime() - select_start_time;
if( time_diff < 10 && time_diff >= 0 ) {
try { Thread.sleep( 10 - time_diff ); }catch(Throwable e) { e.printStackTrace(); }
}
}
*/
}
/*
if ( rm_trace ){
if ( select_start_time - rm_flag_last_log > 10000 ){
rm_flag_last_log = select_start_time;
Iterator it = rm_listener_map.entrySet().iterator();
String str = "";
while( it.hasNext()){
Map.Entry entry = (Map.Entry)it.next();
Class cla = (Class)entry.getKey();
String name = cla.getName();
int pos = name.lastIndexOf('.');
name = name.substring( pos+1 );
int[] counts = (int[])entry.getValue();
str += (str.length()==0?"":",")+ name + ":" + counts[0]+"/"+counts[1]+"/"+counts[2]+"/"+counts[3];
}
Debug.outNoStack( "RM trace: " + hashCode() + ": op=" + INTEREST_OP + "-" + str );
}
}
*/
return count;
}
/**
* Note that you have to ensure that a select operation is performed on the normal select
* loop *after* destroying the selector to actually cause the destroy to occur
*/
public void
destroy()
{
destroyed = true;
}
protected void closeExistingSelector() {
for( Iterator<SelectionKey> i = selector.keys().iterator(); i.hasNext(); ) {
SelectionKey key = i.next();
RegistrationData data = (RegistrationData)key.attachment();
parent.selectFailure(data.listener, data.channel, data.attachment, new Throwable( "selector destroyed" ) );
}
try{
selector.close();
AEDiagnostics.log( "seltrace", "Selector destroyed for '" + parent.getName() + "'," + selector_guard.getType());
}
catch( Throwable t ) { t.printStackTrace(); }
}
private static class RegistrationData {
protected final AbstractSelectableChannel channel;
protected final VirtualChannelSelector.VirtualAbstractSelectorListener listener;
protected final Object attachment;
protected int non_progress_count;
protected long last_select_success_time;
private RegistrationData( AbstractSelectableChannel _channel, VirtualChannelSelector.VirtualAbstractSelectorListener _listener, Object _attachment ) {
channel = _channel;
listener = _listener;
attachment = _attachment;
last_select_success_time = SystemTime.getCurrentTime();
}
}
}