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removed optimization which could make the ca client library

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vulnerable if the following function indicates recv bytes are pending but
recv blocks anyways.

osiSockIoctl_t bytesPending = 0;
int status = socket_ioctl ( this->sock, FIONREAD, & bytesPending );
This commit is contained in:
Jeff Hill
2009-07-17 21:33:18 +00:00
parent 5b62da8229
commit b6a22aa844
1 changed files with 26 additions and 52 deletions
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78
src/ca/tcpiiu.cpp
View File

@@ -456,8 +456,7 @@ void tcpRecvThread::run ()
this->iiu.cacRef.attachToClientCtx ();
comBuf * pComBuf = 0;
bool breakOut = false;
while ( ! breakOut ) {
while ( true ) {
//
// We leave the bytes pending and fetch them after
@@ -473,9 +472,10 @@ void tcpRecvThread::run ()
pComBuf->fillFromWire ( this->iiu, stat );
epicsTime currentTime = epicsTime::getCurrent ();
{
epicsGuard < epicsMutex > guard ( this->iiu.mutex );
if ( ! this->validFillStatus ( guard, stat ) ) {
break;
}
@@ -497,6 +497,7 @@ void tcpRecvThread::run ()
callbackManager mgr ( this->ctxNotify, this->cbMutex );
epicsGuard < epicsMutex > guard ( this->iiu.mutex );
// route legacy V42 channel connect through the recv thread -
// the only thread that should be taking the callback lock
@@ -505,58 +506,31 @@ void tcpRecvThread::run ()
pChan->connect ( mgr.cbGuard, guard );
}
// force the receive watchdog to be reset every 5 frames
unsigned contiguousFrameCount = 0;
while ( stat.bytesCopied ) {
if ( stat.bytesCopied == pComBuf->capacityBytes () ) {
if ( this->iiu.contigRecvMsgCount >=
contiguousMsgCountWhichTriggersFlowControl ) {
this->iiu.busyStateDetected = true;
}
else {
this->iiu.contigRecvMsgCount++;
}
if ( stat.bytesCopied == pComBuf->capacityBytes () ) {
if ( this->iiu.contigRecvMsgCount >=
contiguousMsgCountWhichTriggersFlowControl ) {
this->iiu.busyStateDetected = true;
}
else {
this->iiu.contigRecvMsgCount = 0u;
this->iiu.busyStateDetected = false;
}
this->iiu.unacknowledgedSendBytes = 0u;
else {
this->iiu.contigRecvMsgCount++;
}
}
else {
this->iiu.contigRecvMsgCount = 0u;
this->iiu.busyStateDetected = false;
}
this->iiu.unacknowledgedSendBytes = 0u;
bool protocolOK = false;
{
epicsGuardRelease < epicsMutex > unguard ( guard );
// execute receive labor
protocolOK = this->iiu.processIncoming ( currentTime, mgr );
}
bool protocolOK = false;
{
epicsGuardRelease < epicsMutex > unguard ( guard );
// execute receive labor
protocolOK = this->iiu.processIncoming ( currentTime, mgr );
}
if ( ! protocolOK ) {
this->iiu.initiateAbortShutdown ( guard );
breakOut = true;
break;
}
if ( ! this->iiu.bytesArePendingInOS ()
|| ++contiguousFrameCount > 5 ) {
break;
}
{
epicsGuardRelease < epicsMutex > unguard ( guard );
if ( ! pComBuf ) {
pComBuf = new ( this->iiu.comBufMemMgr ) comBuf;
}
pComBuf->fillFromWire ( this->iiu, stat );
}
if ( this->validFillStatus ( guard, stat ) ) {
this->iiu.recvQue.pushLastComBufReceived ( *pComBuf );
pComBuf = 0;
}
else {
breakOut = true;
break;
}
if ( ! protocolOK ) {
this->iiu.initiateAbortShutdown ( guard );
break;
}
this->iiu._receiveThreadIsBusy = false;
// reschedule connection activity watchdog