EPICS_CA_AUTO_MAX_ARRAY_BYTES -> EPICS_CA_AUTO_ARRAY_BYTES

configure/CONFIG_ENV

@@ -35,7 +35,7 @@ EPICS_CA_CONN_TMO=30.0
 EPICS_CA_REPEATER_PORT=5065
 EPICS_CA_SERVER_PORT=5064
 EPICS_CA_MAX_ARRAY_BYTES=16384
-EPICS_CA_AUTO_MAX_ARRAY_BYTES=NO
+EPICS_CA_AUTO_ARRAY_BYTES=YES
 EPICS_CA_BEACON_PERIOD=15.0
 EPICS_CA_MAX_SEARCH_PERIOD=300.0
 EPICS_CA_MCAST_TTL=1

documentation/RELEASE_NOTES.html

@@ -29,14 +29,17 @@ CA search or beacon packets sent.</p>
 <h3>EPICS_CA_MAX_ARRAY_BYTES is optional</h3>
 
 <p>
-With this change libca, RSRV, and PCAS no longer need to use EPICS_CA_MAX_ARRAY_BYTES
-to set a maximum allocation size.
-The large array free-list is replaced with individual allocations
-when a send/receiver buffer larger than 16KB is needed.
-Add new configuration parameter EPICS_CA_AUTO_MAX_ARRAY_BYTES which defaults to NO.
-libca and RSRV respect EPICS_CA_AUTO_MAX_ARRAY_BYTES=YES.
-PCAS ignores EPICS_CA_AUTO_MAX_ARRAY_BYTES=YES, and thus now ignores EPICS_CA_MAX_ARRAY_BYTES entirely.
-</p>
+A new configuration environment variable EPICS_CA_AUTO_ARRAY_BYTES is used by libca and RSRV
+(CA clients and IOC CA server).
+The default EPICS_CA_AUTO_ARRAY_BYTES=YES removes the limitation of EPICS_CA_MAX_ARRAY_BYTES
+and always attempts to allocate sufficient for a request.
+The value of EPICS_CA_MAX_ARRAY_BYTES is ignored.</>
+
+<p>Explicitly setting EPICS_CA_AUTO_ARRAY_BYTES=NO continues to honor EPICS_CA_AUTO_ARRAY_BYTES
+as in previous releases.</p>
+
+<p>The PCAS server (used by cagateway) now always acts as if EPICS_CA_AUTO_ARRAY_BYTES=YES were
+set.</p>
 
 <h3>Channel Access "modernization"</h3>
 

src/ca/client/CAref.html

@@ -314,6 +314,11 @@ is used.</p>
       <td>i &gt;= 16384</td>
       <td>16384</td>
     </tr>
+    <tr>
+      <td>EPICS_CA_AUTO_ARRAY_BYTES</td>
+      <td>i &gt;= YES</td>
+      <td>YES</td>
+    </tr>
     <tr>
       <td>EPICS_CA_MAX_SEARCH_PERIOD</td>
       <td>r &gt; 60 seconds</td>
@@ -754,6 +759,11 @@ buffers that are used for ordinary communication. If EPICS_CA_MAX_ARRAY_BYTES
 is larger than 16384 then a second free list of larger data buffers is
 established and used only after a client send its first large array request.</p>
 
+<p>Beginning with R3.16.1, EPICS_CA_AUTO_ARRAY_BYTES=YES (the default) will ignore
+EPICS_CA_MAX_ARRAY_BYTES and attempt to allocate sufficient buffer space
+as needed.  Setting EPICS_CA_AUTO_ARRAY_BYTES=NO will continue to respect
+EPICS_CA_MAX_ARRAY_BYTES.</p>
+
 <p>The CA client library uses EPICS_CA_MAX_ARRAY_BYTES to determines the
 maximum array that it will send or receive. Likewise, the CA server uses
 EPICS_CA_MAX_ARRAY_BYTES to determine the maximum array that it may send or

src/ca/client/cac.cpp

@@ -219,11 +219,11 @@ cac::cac (
             throw std::bad_alloc ();
         }
 
-        int caLimitArray;
-        if(envGetBoolConfigParam(&EPICS_CA_AUTO_MAX_ARRAY_BYTES, &caLimitArray))
-            caLimitArray = 0;
+        int autoMaxBytes;
+        if(envGetBoolConfigParam(&EPICS_CA_AUTO_ARRAY_BYTES, &autoMaxBytes))
+            autoMaxBytes = 1;
 
-        if(caLimitArray) {
+        if(!autoMaxBytes) {
             freeListInitPvt ( &this->tcpLargeRecvBufFreeList, this->maxRecvBytesTCP, 1 );
             if ( ! this->tcpLargeRecvBufFreeList ) {
                 throw std::bad_alloc ();

src/ioc/rsrv/caservertask.c

@@ -485,7 +485,7 @@ int rsrv_init (void)
     long maxBytesAsALong;
     long status;
     SOCKET *socks;
-    int caLimitArray;
+    int autoMaxBytes;
 
     clientQlock = epicsMutexMustCreate();
 
@@ -545,10 +545,10 @@ int rsrv_init (void)
         }
     }
 
-    if(envGetBoolConfigParam(&EPICS_CA_AUTO_MAX_ARRAY_BYTES, &caLimitArray))
-        caLimitArray = 0;
+    if(envGetBoolConfigParam(&EPICS_CA_AUTO_ARRAY_BYTES, &autoMaxBytes))
+        autoMaxBytes = 1;
 
-    if (caLimitArray)
+    if (!autoMaxBytes)
         freeListInitPvt ( &rsrvLargeBufFreeListTCP, rsrvSizeofLargeBufTCP, 1 );
     else
         rsrvLargeBufFreeListTCP = NULL;

src/libCom/env/envDefs.h

@@ -48,7 +48,7 @@ epicsShareExtern const ENV_PARAM EPICS_CA_AUTO_ADDR_LIST;
 epicsShareExtern const ENV_PARAM EPICS_CA_REPEATER_PORT;
 epicsShareExtern const ENV_PARAM EPICS_CA_SERVER_PORT;
 epicsShareExtern const ENV_PARAM EPICS_CA_MAX_ARRAY_BYTES;
-epicsShareExtern const ENV_PARAM EPICS_CA_AUTO_MAX_ARRAY_BYTES;
+epicsShareExtern const ENV_PARAM EPICS_CA_AUTO_ARRAY_BYTES;
 epicsShareExtern const ENV_PARAM EPICS_CA_MAX_SEARCH_PERIOD;
 epicsShareExtern const ENV_PARAM EPICS_CA_NAME_SERVERS;
 epicsShareExtern const ENV_PARAM EPICS_CA_MCAST_TTL;