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/981A9DB4-3F0C-4DA5-88AD-CB9CFF4D6CAD@enterprisedb.com

1 files changed, 1 insertions, 1 deletions

diff --git a/src/pl/plperl/plperl.c b/src/pl/plperl/plperl.c
index f5de2332d55..a65bce07135 100644
--- a/src/pl/plperl/plperl.c
+++ b/src/pl/plperl/plperl.c
@@ -1737,7 +1737,7 @@ plperl_event_trigger_build_args(FunctionCallInfo fcinfo)
 	tdata = (EventTriggerData *) fcinfo->context;
 
 	hv_store_string(hv, "event", cstr2sv(tdata->event));
-	hv_store_string(hv, "tag", cstr2sv(tdata->tag));
+	hv_store_string(hv, "tag", cstr2sv(GetCommandTagName(tdata->tag)));
 
 	return newRV_noinc((SV *) hv);
 }