v1-0001-Add-appendStringInfoIdentifier-and-use-it-in-a-fe.patch

From c9e86872d98f4bc948fb370f582941d946887156 Mon Sep 17 00:00:00 2001
From: "Chao Li (Evan)" <lic@highgo.com>
Date: Fri, 14 Nov 2025 21:44:29 +0800
Subject: [PATCH v1 1/2] Add appendStringInfoIdentifier and use it in a few
 places

Author: Chao Li <lic@highgo.com>
---
 src/backend/catalog/objectaddress.c |  20 ++--
 src/backend/commands/explain.c      |   3 +-
 src/backend/utils/adt/ri_triggers.c |   8 +-
 src/backend/utils/adt/ruleutils.c   | 142 +++++++++++++++++++++++-----
 src/include/utils/builtins.h        |   6 ++
 5 files changed, 136 insertions(+), 43 deletions(-)

diff --git a/src/backend/catalog/objectaddress.c b/src/backend/catalog/objectaddress.c
index c75b7131ed7..fbb0b4f30f3 100644
--- a/src/backend/catalog/objectaddress.c
+++ b/src/backend/catalog/objectaddress.c
@@ -3611,9 +3611,9 @@ getObjectDescription(const ObjectAddress *object, bool missing_ok)
 				else
 					nspname = get_namespace_name(cfgForm->cfgnamespace);
 
-				appendStringInfo(&buffer, _("text search configuration %s"),
-								 quote_qualified_identifier(nspname,
-															NameStr(cfgForm->cfgname)));
+				appendStringInfoQualifiedIdentifier(&buffer,
+													_("text search configuration "),
+													nspname, NameStr(cfgForm->cfgname), NULL);
 				ReleaseSysCache(tup);
 				break;
 			}
@@ -4883,8 +4883,7 @@ getObjectIdentityParts(const ObjectAddress *object,
 
 				if (attr)
 				{
-					appendStringInfo(&buffer, ".%s",
-									 quote_identifier(attr));
+					appendStringInfoIdentifier(&buffer, ".", attr, NULL);
 					if (objname)
 						*objname = lappend(*objname, attr);
 				}
@@ -5395,8 +5394,7 @@ getObjectIdentityParts(const ObjectAddress *object,
 							 object->objectId);
 					break;
 				}
-				appendStringInfoString(&buffer,
-									   quote_identifier(nspname));
+				appendStringInfoIdentifier(&buffer, NULL, nspname, NULL);
 				if (objname)
 					*objname = list_make1(nspname);
 				break;
@@ -5739,16 +5737,12 @@ getObjectIdentityParts(const ObjectAddress *object,
 				defacl = (Form_pg_default_acl) GETSTRUCT(tup);
 
 				username = GetUserNameFromId(defacl->defaclrole, false);
-				appendStringInfo(&buffer,
-								 "for role %s",
-								 quote_identifier(username));
+				appendStringInfoIdentifier(&buffer, "for role ", username, NULL);
 
 				if (OidIsValid(defacl->defaclnamespace))
 				{
 					schema = get_namespace_name_or_temp(defacl->defaclnamespace);
-					appendStringInfo(&buffer,
-									 " in schema %s",
-									 quote_identifier(schema));
+					appendStringInfoIdentifier(&buffer, " in schema ", schema, NULL);
 				}
 				else
 					schema = NULL;
diff --git a/src/backend/commands/explain.c b/src/backend/commands/explain.c
index 7e699f8595e..cc979737845 100644
--- a/src/backend/commands/explain.c
+++ b/src/backend/commands/explain.c
@@ -1705,8 +1705,7 @@ ExplainNode(PlanState *planstate, List *ancestors,
 					explain_get_index_name(bitmapindexscan->indexid);
 
 				if (es->format == EXPLAIN_FORMAT_TEXT)
-					appendStringInfo(es->str, " on %s",
-									 quote_identifier(indexname));
+					appendStringInfoIdentifier(es->str,	" on ", indexname, NULL);
 				else
 					ExplainPropertyText("Index Name", indexname, es);
 			}
diff --git a/src/backend/utils/adt/ri_triggers.c b/src/backend/utils/adt/ri_triggers.c
index 059fc5ebf60..9e13f526994 100644
--- a/src/backend/utils/adt/ri_triggers.c
+++ b/src/backend/utils/adt/ri_triggers.c
@@ -395,7 +395,6 @@ RI_FKey_check(TriggerData *trigdata)
 		{
 			quoteOneName(attname,
 						 RIAttName(pk_rel, riinfo->pk_attnums[riinfo->nkeys - 1]));
-
 			appendStringInfo(&querybuf,
 							 "SELECT 1 FROM (SELECT %s AS r FROM %s%s x",
 							 attname, pk_only, pkrelname);
@@ -2095,7 +2094,6 @@ ri_GenerateQualCollation(StringInfo buf, Oid collation)
 	HeapTuple	tp;
 	Form_pg_collation colltup;
 	char	   *collname;
-	char		onename[MAX_QUOTED_NAME_LEN];
 
 	/* Nothing to do if it's a noncollatable data type */
 	if (!OidIsValid(collation))
@@ -2111,10 +2109,8 @@ ri_GenerateQualCollation(StringInfo buf, Oid collation)
 	 * We qualify the name always, for simplicity and to ensure the query is
 	 * not search-path-dependent.
 	 */
-	quoteOneName(onename, get_namespace_name(colltup->collnamespace));
-	appendStringInfo(buf, " COLLATE %s", onename);
-	quoteOneName(onename, collname);
-	appendStringInfo(buf, ".%s", onename);
+	appendStringInfoIdentifier(buf, " COLLATE ", get_namespace_name(colltup->collnamespace), NULL);
+	appendStringInfoIdentifier(buf, ".", collname, NULL);
 
 	ReleaseSysCache(tp);
 }
diff --git a/src/backend/utils/adt/ruleutils.c b/src/backend/utils/adt/ruleutils.c
index 556ab057e5a..1d767deb6c4 100644
--- a/src/backend/utils/adt/ruleutils.c
+++ b/src/backend/utils/adt/ruleutils.c
@@ -13052,25 +13052,17 @@ printSubscripts(SubscriptingRef *sbsref, deparse_context *context)
 	}
 }
 
-/*
- * quote_identifier			- Quote an identifier only if needed
- *
- * When quotes are needed, we palloc the required space; slightly
- * space-wasteful but well worth it for notational simplicity.
- */
-const char *
-quote_identifier(const char *ident)
+static inline bool
+is_identifier_safe(const char *ident, int *nquotes)
 {
 	/*
 	 * Can avoid quoting if ident starts with a lowercase letter or underscore
 	 * and contains only lowercase letters, digits, and underscores, *and* is
 	 * not any SQL keyword.  Otherwise, supply quotes.
 	 */
-	int			nquotes = 0;
 	bool		safe;
-	const char *ptr;
-	char	   *result;
-	char	   *optr;
+
+	*nquotes = 0;
 
 	/*
 	 * would like to use <ctype.h> macros here, but they might yield unwanted
@@ -13078,7 +13070,7 @@ quote_identifier(const char *ident)
 	 */
 	safe = ((ident[0] >= 'a' && ident[0] <= 'z') || ident[0] == '_');
 
-	for (ptr = ident; *ptr; ptr++)
+	for (const char *ptr = ident; *ptr; ptr++)
 	{
 		char		ch = *ptr;
 
@@ -13092,7 +13084,7 @@ quote_identifier(const char *ident)
 		{
 			safe = false;
 			if (ch == '"')
-				nquotes++;
+				(*nquotes)++;
 		}
 	}
 
@@ -13115,14 +13107,20 @@ quote_identifier(const char *ident)
 			safe = false;
 	}
 
-	if (safe)
-		return ident;			/* no change needed */
+	return safe;
+}
 
-	result = (char *) palloc(strlen(ident) + nquotes + 2 + 1);
+static inline const char *
+quote_identifier_internal(const char *ident, int nquotes, char **result)
+{
+	char	   *optr;
 
-	optr = result;
+	if (*result == NULL)
+		*result = (char *) palloc(strlen(ident) + nquotes + 2 + 1);
+
+	optr = *result;
 	*optr++ = '"';
-	for (ptr = ident; *ptr; ptr++)
+	for (const char *ptr = ident; *ptr; ptr++)
 	{
 		char		ch = *ptr;
 
@@ -13133,7 +13131,107 @@ quote_identifier(const char *ident)
 	*optr++ = '"';
 	*optr = '\0';
 
-	return result;
+	return *result;
+}
+
+/*
+ * quote_identifier			- Quote an identifier only if needed
+ *
+ * When quotes are needed, we palloc the required space; slightly
+ * space-wasteful but well worth it for notational simplicity.
+ */
+const char *
+quote_identifier(const char *ident)
+{
+	int			nquotes;
+	bool		safe;
+	char	   *result = NULL;
+
+	safe = is_identifier_safe(ident, &nquotes);
+	if (safe)
+		return ident;			/* no change needed */
+
+	return quote_identifier_internal(ident, nquotes, &result);
+}
+
+/*
+ * appendStringInfoIdentifier
+ *      Append an SQL identifier to a StringInfo, quoting if required.
+ *
+ * This behaves like writing prefix + quote_identifier(ident) + suffix into
+ * the StringInfo, but emits the identifier directly into the buffer to avoid
+ * an intermediate palloc.  prefix and suffix may be NULL.
+ *
+ * The identifier is copied verbatim if it is safe to leave unquoted; otherwise
+ * it is written with double quotes and embedded double quotes are doubled.
+ * Quoting rules are local to ruleutils, so this helper is defined here rather
+ * than in stringinfo.c.
+ */
+
+void
+appendStringInfoIdentifier(StringInfo str, const char *prefix,
+						   const char *ident, const char *suffix)
+{
+	int			nquotes;
+	bool		safe;
+	int			ident_len;
+	int			prefix_len = 0;
+	int			suffix_len = 0;
+
+	safe = is_identifier_safe(ident, &nquotes);
+	if (safe)
+		ident_len = strlen(ident);
+	else
+		ident_len = strlen(ident) + nquotes + 2;	/* quotes + possible
+													 * escapes */
+
+	if (prefix != NULL)
+		prefix_len = strlen(prefix);
+
+	if (suffix != NULL)
+		suffix_len = strlen(suffix);
+
+	enlargeStringInfo(str, ident_len + prefix_len + suffix_len + 1);	/* +1 for trailing null */
+
+	if (prefix != NULL)
+		appendBinaryStringInfo(str, prefix, prefix_len);
+
+	if (safe)
+		appendBinaryStringInfo(str, ident, ident_len);
+	else
+	{
+		char	   *result = str->data + str->len;
+
+		(void) quote_identifier_internal(ident, nquotes, &result);
+		str->len += ident_len;
+		str->data[str->len] = '\0';
+	}
+
+	if (suffix != NULL)
+		appendBinaryStringInfo(str, suffix, suffix_len);
+}
+
+/*
+ * appendStringInfoQualifiedIdentifier
+ *      Append a (possibly) qualified SQL identifier to a StringInfo.
+ *
+ * Writes prefix + qualifier + '.' + ident + suffix, quoting each identifier
+ * component if needed.  If no qualifier is given, only ident (plus optional
+ * prefix/suffix) is appended.  prefix and suffix may be NULL.
+ *
+ * This is a convenience wrapper around appendStringInfoIdentifier().
+ */
+void
+appendStringInfoQualifiedIdentifier(StringInfo str, const char *prefix,
+									const char *qualifier, const char *ident,
+									const char *suffix)
+{
+	if (qualifier)
+	{
+		appendStringInfoIdentifier(str, prefix, qualifier, ".");
+		prefix = NULL;
+	}
+	appendStringInfoIdentifier(str, prefix, ident, suffix);
 }
 
 /*
@@ -13150,8 +13248,8 @@ quote_qualified_identifier(const char *qualifier,
 
 	initStringInfo(&buf);
 	if (qualifier)
-		appendStringInfo(&buf, "%s.", quote_identifier(qualifier));
-	appendStringInfoString(&buf, quote_identifier(ident));
+		appendStringInfoIdentifier(&buf, NULL, qualifier, ".");
+	appendStringInfoIdentifier(&buf, NULL, ident, NULL);
 	return buf.data;
 }
 
diff --git a/src/include/utils/builtins.h b/src/include/utils/builtins.h
index ce6285a2c03..ff4ba7265c2 100644
--- a/src/include/utils/builtins.h
+++ b/src/include/utils/builtins.h
@@ -84,6 +84,12 @@ extern void generate_operator_clause(StringInfo buf,
 									 const char *leftop, Oid leftoptype,
 									 Oid opoid,
 									 const char *rightop, Oid rightoptype);
+extern void appendStringInfoIdentifier(StringInfo str, const char *prefix, const char *ident, const char *suffix);
+extern void appendStringInfoQualifiedIdentifier(StringInfo str,
+												const char *prefix,
+												const char *qualifier,
+												const char *ident,
+												const char *suffix);
 
 /* varchar.c */
 extern int	bpchartruelen(char *s, int len);
-- 
2.39.5 (Apple Git-154)