Use PqMsg_* macros in fe-protocol3.c.

Oversight in commit f4b54e1. Reviewed-by: Jacob Champion <jacob.champion@enterprisedb.com> Reviewed-by: Fabrízio de Royes Mello <fabriziomello@gmail.com> Discussion: https://postgr.es/m/aKx5vEbbP03JNgtp%40nathan

Author: nathan-bossart

src/include/libpq/protocol.h

@@ -66,6 +66,7 @@
 
 
 /* These are the codes sent by parallel workers to leader processes. */
+
 #define PqMsg_Progress 'P'
 
 

src/interfaces/libpq/fe-protocol3.c

@@ -2262,7 +2262,7 @@ pqFunctionCall3(PGconn *conn, Oid fnid,
  */
 switch (id)
 {
-case 'V':/* function result */
+case PqMsg_FunctionCallResponse:
 if (pqGetInt(actual_result_len, 4, conn))
 continue;
 if (*actual_result_len != -1)
@@ -2283,22 +2283,22 @@ pqFunctionCall3(PGconn *conn, Oid fnid,
 /* correctly finished function result message */
 status = PGRES_COMMAND_OK;
 break;
-case 'E':/* error return */
+case PqMsg_ErrorResponse:
 if (pqGetErrorNotice3(conn, true))
 continue;
 status = PGRES_FATAL_ERROR;
 break;
-case 'A':/* notify message */
+case PqMsg_NotificationResponse:
 /* handle notify and go back to processing return values */
 if (getNotify(conn))
 continue;
 break;
-case 'N':/* notice */
+case PqMsg_NoticeResponse:
 /* handle notice and go back to processing return values */
 if (pqGetErrorNotice3(conn, false))
 continue;
 break;
-case 'Z':/* backend is ready for new query */
+case PqMsg_ReadyForQuery:
 if (getReadyForQuery(conn))
 continue;
 
@@ -2330,7 +2330,7 @@ pqFunctionCall3(PGconn *conn, Oid fnid,
 }
 /* and we're out */
 return pqPrepareAsyncResult(conn);
-case 'S':/* parameter status */
+case PqMsg_ParameterStatus:
 if (getParameterStatus(conn))
 continue;
 break;