Represent command completion tags as structs

The backend was using strings to represent command tags and doing string
comparisons in multiple places, but that's slow and unhelpful.  Create a
new command list with a supporting structure to use instead; this is
stored in a tag-list-file that can be tailored to specific purposes with
a caller-definable C macro, similar to what we do for WAL resource
managers.  The first first such uses are a new CommandTag enum and a
CommandTagBehavior struct.

Replace numerous occurrences of char *completionTag with a
QueryCompletion struct so that the code no longer stores information
about completed queries in a cstring.  Only at the last moment, in
EndCommand(), does this get converted to a string.

EventTriggerCacheItem no longer holds an array of palloc’d tag strings
in sorted order, but rather just a Bitmapset over the CommandTags.

Author: Mark Dilger, with unsolicited help from Álvaro Herrera
Reviewed-by: John Naylor, Tom Lane
Discussion: https://postgr.es/m/[email protected]

1 files changed, 2 insertions, 2 deletions

diff --git a/src/backend/commands/prepare.c b/src/backend/commands/prepare.c
index c4e4b6eaec6..f917fc9c7a7 100644
--- a/src/backend/commands/prepare.c
+++ b/src/backend/commands/prepare.c
@@ -187,7 +187,7 @@ void
 ExecuteQuery(ParseState *pstate,
 			 ExecuteStmt *stmt, IntoClause *intoClause,
 			 ParamListInfo params,
-			 DestReceiver *dest, char *completionTag)
+			 DestReceiver *dest, QueryCompletion *qc)
 {
 	PreparedStatement *entry;
 	CachedPlan *cplan;
@@ -288,7 +288,7 @@ ExecuteQuery(ParseState *pstate,
 	 */
 	PortalStart(portal, paramLI, eflags, GetActiveSnapshot());
 
-	(void) PortalRun(portal, count, false, true, dest, dest, completionTag);
+	(void) PortalRun(portal, count, false, true, dest, dest, qc);
 
 	PortalDrop(portal, false);