void
tr_bandwidthAllocate( tr_bandwidth * b,
tr_direction dir,
unsigned int period_msec )
{
int i, peerCount;
tr_ptrArray tmp = TR_PTR_ARRAY_INIT;
tr_ptrArray low = TR_PTR_ARRAY_INIT;
tr_ptrArray high = TR_PTR_ARRAY_INIT;
tr_ptrArray normal = TR_PTR_ARRAY_INIT;
struct tr_peerIo ** peers;
/* allocateBandwidth() is a helper function with two purposes:
* 1. allocate bandwidth to b and its subtree
* 2. accumulate an array of all the peerIos from b and its subtree. */
allocateBandwidth( b, TR_PRI_LOW, dir, period_msec, &tmp );
peers = (struct tr_peerIo**) tr_ptrArrayBase( &tmp );
peerCount = tr_ptrArraySize( &tmp );
for( i=0; i<peerCount; ++i )
{
tr_peerIo * io = peers[i];
tr_peerIoRef( io );
tr_peerIoFlushOutgoingProtocolMsgs( io );
switch( io->priority ) {
case TR_PRI_HIGH:
tr_ptrArrayAppend( &high, io ); /* fall through */
case TR_PRI_NORMAL:
tr_ptrArrayAppend( &normal, io ); /* fall through */
default:
tr_ptrArrayAppend( &low, io );
}
}
/* First phase of IO. Tries to distribute bandwidth fairly to keep faster
* peers from starving the others. Loop through the peers, giving each a
* small chunk of bandwidth. Keep looping until we run out of bandwidth
* and/or peers that can use it */
phaseOne( &high, dir );
phaseOne( &normal, dir );
phaseOne( &low, dir );
/* Second phase of IO. To help us scale in high bandwidth situations,
* enable on-demand IO for peers with bandwidth left to burn.
* This on-demand IO is enabled until (1) the peer runs out of bandwidth,
* or (2) the next tr_bandwidthAllocate() call, when we start over again. */
for( i=0; i<peerCount; ++i )
tr_peerIoSetEnabled( peers[i], dir, tr_peerIoHasBandwidthLeft( peers[i], dir ) );
for( i=0; i<peerCount; ++i )
tr_peerIoUnref( peers[i] );
/* cleanup */
tr_ptrArrayDestruct( &normal, NULL );
tr_ptrArrayDestruct( &high, NULL );
tr_ptrArrayDestruct( &low, NULL );
tr_ptrArrayDestruct( &tmp, NULL );
}
static void
tr_handshakeFree( tr_handshake * handshake )
{
if( handshake->io )
tr_peerIoUnref( handshake->io ); /* balanced by the ref in tr_handshakeNew */
event_free( handshake->timeout_timer );
tr_free( handshake );
}
static void
canReadWrapper( tr_peerIo * io )
{
tr_bool err = 0;
tr_bool done = 0;
tr_session * session;
dbgmsg( io, "canRead" );
assert( tr_isPeerIo( io ) );
assert( tr_isSession( io->session ) );
tr_peerIoRef( io );
session = io->session;
/* try to consume the input buffer */
if( io->canRead )
{
tr_sessionLock( session );
while( !done && !err )
{
size_t piece = 0;
const size_t oldLen = EVBUFFER_LENGTH( io->inbuf );
const int ret = io->canRead( io, io->userData, &piece );
const size_t used = oldLen - EVBUFFER_LENGTH( io->inbuf );
assert( tr_isPeerIo( io ) );
if( piece || (piece!=used) )
{
const uint64_t now = tr_time_msec( );
if( piece )
tr_bandwidthUsed( &io->bandwidth, TR_DOWN, piece, TRUE, now );
if( used != piece )
tr_bandwidthUsed( &io->bandwidth, TR_DOWN, used - piece, FALSE, now );
}
switch( ret )
{
case READ_NOW:
if( EVBUFFER_LENGTH( io->inbuf ) )
continue;
done = 1;
break;
case READ_LATER:
done = 1;
break;
case READ_ERR:
err = 1;
break;
}
assert( tr_isPeerIo( io ) );
}
tr_sessionUnlock( session );
}
/* keep the iobuf's excess capacity from growing too large */
if( EVBUFFER_LENGTH( io->inbuf ) == 0 ) {
evbuffer_free( io->inbuf );
io->inbuf = evbuffer_new( );
}
assert( tr_isPeerIo( io ) );
tr_peerIoUnref( io );
}