Fixup various StringInfo function usages

This adjusts various appendStringInfo* function calls to use a more
appropriate and efficient function with the same behavior.  For example,
use appendStringInfoChar() when appending a single character rather than
appendStringInfo() and appendStringInfoString() when no formatting is
required rather than using appendStringInfo().

All adjustments made here are in code that's new to v17, so it makes
sense to fix these now rather than wait a few years and make
backpatching harder.

Discussion: https://postgr.es/m/CAApHDvojY2UvMiO+9_55ArTj10P1LBNJyyoGB+C65BLDNT0GsQ@mail.gmail.com
Reviewed-by: Nathan Bossart, Tom Lane

contrib/postgres_fdw/deparse.c

@@ -1887,7 +1887,7 @@ deparseFromExprForRel(StringInfo buf, PlannerInfo *root, RelOptInfo *foreignrel,
 				}
 
 				/* Close parentheses for EXISTS subquery */
-				appendStringInfo(&str, ")");
+				appendStringInfoChar(&str, ')');
 
 				*additional_conds = lappend(*additional_conds, str.data);
 			}
@@ -1921,7 +1921,7 @@ deparseFromExprForRel(StringInfo buf, PlannerInfo *root, RelOptInfo *foreignrel,
 		 */
 		if (fpinfo->jointype == JOIN_SEMI)
 		{
-			appendStringInfo(buf, "%s", join_sql_o.data);
+			appendBinaryStringInfo(buf, join_sql_o.data, join_sql_o.len);
 		}
 		else
 		{

src/backend/replication/logical/slotsync.c

@@ -1311,7 +1311,7 @@ ReplSlotSyncWorkerMain(char *startup_data, size_t startup_data_len)
 	if (cluster_name[0])
 		appendStringInfo(&app_name, "%s_%s", cluster_name, "slotsync worker");
 	else
-		appendStringInfo(&app_name, "%s", "slotsync worker");
+		appendStringInfoString(&app_name, "slotsync worker");
 
 	/*
 	 * Establish the connection to the primary server for slot

src/backend/replication/logical/tablesync.c

@@ -1154,7 +1154,7 @@ copy_table(Relation rel)
 				appendStringInfoString(&cmd, quote_identifier(lrel.attnames[i]));
 			}
 
-			appendStringInfoString(&cmd, ")");
+			appendStringInfoChar(&cmd, ')');
 		}
 
 		appendStringInfoString(&cmd, " TO STDOUT");

src/backend/utils/adt/ri_triggers.c

@@ -426,13 +426,13 @@ RI_FKey_check(TriggerData *trigdata)
 		{
 			Oid			fk_type = RIAttType(fk_rel, riinfo->fk_attnums[riinfo->nkeys - 1]);
 
-			appendStringInfo(&querybuf, ") x1 HAVING ");
+			appendStringInfoString(&querybuf, ") x1 HAVING ");
 			sprintf(paramname, "$%d", riinfo->nkeys);
 			ri_GenerateQual(&querybuf, "",
 							paramname, fk_type,
 							riinfo->agged_period_contained_by_oper,
 							"pg_catalog.range_agg", ANYMULTIRANGEOID);
-			appendStringInfo(&querybuf, "(x1.r)");
+			appendStringInfoString(&querybuf, "(x1.r)");
 		}
 
 		/* Prepare and save the plan */
@@ -594,13 +594,13 @@ ri_Check_Pk_Match(Relation pk_rel, Relation fk_rel,
 		{
 			Oid			fk_type = RIAttType(fk_rel, riinfo->fk_attnums[riinfo->nkeys - 1]);
 
-			appendStringInfo(&querybuf, ") x1 HAVING ");
+			appendStringInfoString(&querybuf, ") x1 HAVING ");
 			sprintf(paramname, "$%d", riinfo->nkeys);
 			ri_GenerateQual(&querybuf, "",
 							paramname, fk_type,
 							riinfo->agged_period_contained_by_oper,
 							"pg_catalog.range_agg", ANYMULTIRANGEOID);
-			appendStringInfo(&querybuf, "(x1.r)");
+			appendStringInfoString(&querybuf, "(x1.r)");
 		}
 
 		/* Prepare and save the plan */

src/backend/utils/adt/ruleutils.c

@@ -7176,16 +7176,16 @@ get_merge_query_def(Query *query, deparse_context *context,
 		switch (action->matchKind)
 		{
 			case MERGE_WHEN_MATCHED:
-				appendStringInfo(buf, "MATCHED");
+				appendStringInfoString(buf, "MATCHED");
 				break;
 			case MERGE_WHEN_NOT_MATCHED_BY_SOURCE:
-				appendStringInfo(buf, "NOT MATCHED BY SOURCE");
+				appendStringInfoString(buf, "NOT MATCHED BY SOURCE");
 				break;
 			case MERGE_WHEN_NOT_MATCHED_BY_TARGET:
 				if (haveNotMatchedBySource)
-					appendStringInfo(buf, "NOT MATCHED BY TARGET");
+					appendStringInfoString(buf, "NOT MATCHED BY TARGET");
 				else
-					appendStringInfo(buf, "NOT MATCHED");
+					appendStringInfoString(buf, "NOT MATCHED");
 				break;
 			default:
 				elog(ERROR, "unrecognized matchKind: %d",
@@ -8850,18 +8850,18 @@ get_json_expr_options(JsonExpr *jsexpr, deparse_context *context,
 	if (jsexpr->op == JSON_QUERY_OP)
 	{
 		if (jsexpr->wrapper == JSW_CONDITIONAL)
-			appendStringInfo(context->buf, " WITH CONDITIONAL WRAPPER");
+			appendStringInfoString(context->buf, " WITH CONDITIONAL WRAPPER");
 		else if (jsexpr->wrapper == JSW_UNCONDITIONAL)
-			appendStringInfo(context->buf, " WITH UNCONDITIONAL WRAPPER");
+			appendStringInfoString(context->buf, " WITH UNCONDITIONAL WRAPPER");
 		/* The default */
 		else if (jsexpr->wrapper == JSW_NONE || jsexpr->wrapper == JSW_UNSPEC)
-			appendStringInfo(context->buf, " WITHOUT WRAPPER");
+			appendStringInfoString(context->buf, " WITHOUT WRAPPER");
 
 		if (jsexpr->omit_quotes)
-			appendStringInfo(context->buf, " OMIT QUOTES");
+			appendStringInfoString(context->buf, " OMIT QUOTES");
 		/* The default */
 		else
-			appendStringInfo(context->buf, " KEEP QUOTES");
+			appendStringInfoString(context->buf, " KEEP QUOTES");
 	}
 
 	if (jsexpr->on_empty && jsexpr->on_empty->btype != default_behavior)
@@ -10206,7 +10206,7 @@ get_rule_expr(Node *node, deparse_context *context,
 									  JSON_BEHAVIOR_NULL :
 									  JSON_BEHAVIOR_FALSE);
 
-				appendStringInfoString(buf, ")");
+				appendStringInfoChar(buf, ')');
 			}
 			break;