From d3568605ce7bbd5d063a77f2f2a29f83a23cee3c Mon Sep 17 00:00:00 2001
From: Bruce Hill <bhill@slac.stanford.edu>
Date: Tue, 6 Dec 2016 13:43:59 -0800
Subject: [PATCH] Fetch nativeCount() in casChannelI constructor to avoid
 deadlock if we fetch it from eventSysProcess()

---
 src/cas/generic/casChannelI.cc   | 1 +
 src/cas/generic/casChannelI.h    | 7 +++++++
 src/cas/generic/casStrmClient.cc | 8 ++++----
 3 files changed, 12 insertions(+), 4 deletions(-)

diff --git a/src/cas/generic/casChannelI.cc b/src/cas/generic/casChannelI.cc
index 588f67d78..c575ea483 100644
--- a/src/cas/generic/casChannelI.cc
+++ b/src/cas/generic/casChannelI.cc
@@ -21,6 +21,7 @@ casChannelI::casChannelI ( casCoreClient & clientIn,
     casChannel & chanIn, casPVI & pvIn, ca_uint32_t cidIn ) :
         privateForPV ( clientIn, *this ),
         pv ( pvIn ), 
+        maxElem( pvIn.nativeCount() ),
         chan ( chanIn ), 
         cid ( cidIn ), 
         serverDeletePending ( false ), 
diff --git a/src/cas/generic/casChannelI.h b/src/cas/generic/casChannelI.h
index 2c72e88e4..228fe6ab3 100644
--- a/src/cas/generic/casChannelI.h
+++ b/src/cas/generic/casChannelI.h
@@ -45,6 +45,7 @@ public:
 	void clearOutstandingReads ();
 	void postAccessRightsEvent ();
     const gddEnumStringTable & enumStringTable () const;
+	ca_uint32_t getMaxElem () const;
 	void setOwner ( const char * const pUserName, 
 		const char * const pHostName );
 	bool readAccess () const;
@@ -58,6 +59,7 @@ private:
     chanIntfForPV privateForPV;
 	tsDLList < casAsyncIOI > ioList;
 	casPVI & pv;
+	ca_uint32_t maxElem;
     casChannel & chan;
 	caResId cid; // client id 
     bool serverDeletePending;
@@ -77,6 +79,11 @@ inline casPVI & casChannelI::getPVI () const
 	return this->pv;
 }
 
+inline  ca_uint32_t casChannelI::getMaxElem () const 
+{
+    return this->maxElem;
+}
+
 inline const caResId casChannelI::getCID () 
 {
 	return this->cid;
diff --git a/src/cas/generic/casStrmClient.cc b/src/cas/generic/casStrmClient.cc
index e23a2b8df..60903787c 100644
--- a/src/cas/generic/casStrmClient.cc
+++ b/src/cas/generic/casStrmClient.cc
@@ -409,7 +409,7 @@ caStatus casStrmClient::verifyRequest (casChannelI * & pChan , bool allowdyn)
     //
     // element count out of range ?
     //
-    if ( ctx.msg.m_count > pChan->getPVI().nativeCount() ||
+    if ( ctx.msg.m_count > pChan->getMaxElem() ||
          ( !allowdyn && ctx.msg.m_count == 0u ) ) {
         return ECA_BADCOUNT;
     }
@@ -895,7 +895,7 @@ caStatus casStrmClient::monitorResponse (
     gdd * pDBRDD = 0;
     if ( completionStatus == S_cas_success ) {
         caStatus status = createDBRDD ( msg.m_dataType, count,
-                chan.getPVI().nativeCount(), pDBRDD );
+                chan.getMaxElem(), pDBRDD );
         if ( status != S_cas_success ) {
             caStatus ecaStatus;
             if ( status == S_cas_badType ) {
@@ -1866,7 +1866,7 @@ caStatus casStrmClient::privateCreateChanResponse (
     // the protocol buffer.
     //
     assert ( nativeTypeDBR <= 0xffff );
-    aitIndex nativeCount = chan.getPVI().nativeCount();
+    aitIndex nativeCount = chan.getMaxElem();
     assert ( nativeCount <= 0xffffffff );
     assert ( hdr.m_cid == chan.getCID() );
     status = this->out.copyInHeader ( CA_PROTO_CREATE_CHAN, 0,
@@ -2626,7 +2626,7 @@ caStatus casStrmClient::read ()
     {
         gdd * pDD = 0;
         caStatus status = createDBRDD ( pHdr->m_dataType, pHdr->m_count,
-                this->ctx.getChannel()->getPVI().nativeCount(), pDD );
+                this->ctx.getChannel()->getMaxElem(), pDD );
         if ( status != S_cas_success ) {
             return status;
         }