made CA client service list an epics singleton

src/ca/cac.cpp

@@ -664,7 +664,7 @@ cacChannel & cac::createChannel ( const char * pName,
 
     pIO = this->services.createChannel ( pName, chan, pri );
     if ( ! pIO ) {
-        pIO = cacGlobalServiceList.createChannel ( pName, chan, pri );
+        pIO = pGlobalServiceListCAC->createChannel ( pName, chan, pri );
         if ( ! pIO ) {
             if ( ! this->pudpiiu || ! this->pSearchTmr ) {
                 if ( ! this->setupUDP () ) {

src/ca/cacIO.h

@@ -238,7 +238,8 @@ private:
 	cacServiceList & operator = ( const cacServiceList & );
 };
 
-epicsShareExtern cacServiceList cacGlobalServiceList;
+template < class T > class epicsSingleton;
+epicsShareExtern epicsSingleton < cacServiceList > pGlobalServiceListCAC;
 
 epicsShareFunc int epicsShareAPI ca_register_service ( cacService *pService );
 

src/ca/cacServiceList.cpp

@@ -14,14 +14,14 @@
  *	505 665 1831
  */
 
-#include "iocinf.h"
-#include "epicsGuard.h"
+#include "epicsSingleton.h"
 
 #define epicsExportSharedSymbols
+#include "iocinf.h"
+#include "epicsGuard.h"
 #include "cacIO.h"
-#undef epicsExportSharedSymbols
 
-epicsShareDef cacServiceList cacGlobalServiceList;
+epicsShareDef epicsSingleton < cacServiceList > pGlobalServiceListCAC;
 
 cacServiceList::cacServiceList ()
 {

src/db/dbServiceIO.cpp

@@ -52,7 +52,7 @@ dbBaseIO::dbBaseIO () {}
 
 dbServiceIOLoadTimeInit::dbServiceIOLoadTimeInit ()
 {
-    cacGlobalServiceList.registerService ( this->dbio );
+    pGlobalServiceListCAC->registerService ( this->dbio );
 }
 
 dbServiceIO::dbServiceIO () :