From e5823beb79599bf17ba45f19fcca54c75f85c82d Mon Sep 17 00:00:00 2001
From: Nathan Bossart <nathan@postgresql.org>
Date: Tue, 26 May 2026 11:12:49 -0500
Subject: [PATCH v1 3/3] LO frontend PQexecParams

---
 src/interfaces/libpq/fe-connect.c |   1 -
 src/interfaces/libpq/fe-lobj.c    | 236 ++++--------------------------
 src/interfaces/libpq/libpq-int.h  |   1 -
 3 files changed, 26 insertions(+), 212 deletions(-)

diff --git a/src/interfaces/libpq/fe-connect.c b/src/interfaces/libpq/fe-connect.c
index 01c9735f276..9f6aa01dc0e 100644
--- a/src/interfaces/libpq/fe-connect.c
+++ b/src/interfaces/libpq/fe-connect.c
@@ -692,7 +692,6 @@ pqDropServerData(PGconn *conn)
 	conn->in_hot_standby = PG_BOOL_UNKNOWN;
 	conn->scram_sha_256_iterations = SCRAM_SHA_256_DEFAULT_ITERATIONS;
 	conn->sversion = 0;
-	conn->lobjprepared = false;
 
 	/* Reset assorted other per-connection state */
 	conn->last_sqlstate[0] = '\0';
diff --git a/src/interfaces/libpq/fe-lobj.c b/src/interfaces/libpq/fe-lobj.c
index 41573c22c80..17c1d699a48 100644
--- a/src/interfaces/libpq/fe-lobj.c
+++ b/src/interfaces/libpq/fe-lobj.c
@@ -41,89 +41,6 @@
 
 #define LO_BUFSIZE		  8192
 
-typedef struct PGlobjfuncs
-{
-	char	   *name;
-	char	   *args;
-	int			nargs;
-	int			version;
-} PGlobjfuncs;
-
-static const PGlobjfuncs lobjfuncs[] =
-{
-	{
-		"lo_open",
-		"$1::pg_catalog.oid, $2::pg_catalog.int4",
-		2
-	},
-	{
-		"lo_close",
-		"$1::pg_catalog.int4",
-		1
-	},
-	{
-		"lo_creat",
-		"$1::pg_catalog.int4",
-		1
-	},
-	{
-		"lo_create",
-		"$1::pg_catalog.oid",
-		1,
-		80100
-	},
-	{
-		"lo_unlink",
-		"$1::pg_catalog.oid",
-		1
-	},
-	{
-		"lo_lseek",
-		"$1::pg_catalog.int4, $2::pg_catalog.int4, $3::pg_catalog.int4",
-		3
-	},
-	{
-		"lo_lseek64",
-		"$1::pg_catalog.int4, $2::pg_catalog.int8, $3::pg_catalog.int4",
-		3,
-		90300
-	},
-	{
-		"lo_tell",
-		"$1::pg_catalog.int4",
-		1
-	},
-	{
-		"lo_tell64",
-		"$1::pg_catalog.int4",
-		1,
-		90300
-	},
-	{
-		"lo_truncate",
-		"$1::pg_catalog.int4, $2::pg_catalog.int4",
-		2,
-		80300
-	},
-	{
-		"lo_truncate64",
-		"$1::pg_catalog.int4, $2::pg_catalog.int8",
-		2,
-		90300
-	},
-	{
-		"loread",
-		"$1::pg_catalog.int4, $2::pg_catalog.int4",
-		2
-	},
-	{
-		"lowrite",
-		"$1::pg_catalog.int4, $2::pg_catalog.bytea",
-		2
-	}
-};
-
-static int	lo_initialize(PGconn *conn);
 static Oid	lo_import_internal(PGconn *conn, const char *filename, Oid oid);
 
 static bool
@@ -153,17 +70,14 @@ lo_open(PGconn *conn, Oid lobjId, int mode)
 	int			argFormats[] = {1, 1};
 	PGresult   *res;
 
-	if (lo_initialize(conn) < 0)
-		return -1;
-
 	lobjId = pg_hton32(lobjId);
 	argv[0] = (char *) &lobjId;
 
 	mode = pg_hton32(mode);
 	argv[1] = (char *) &mode;
 
-	res = PQexecPrepared(conn, "libpq_internal_lo_open", 2,
-						 (const char *const *) argv, argLens, argFormats, 1);
+	res = PQexecParams(conn, "SELECT pg_catalog.lo_open($1::pg_catalog.oid, $2::pg_catalog.int4)", 2, NULL,
+					   (const char *const *) argv, argLens, argFormats, 1);
 
 	if (lo_result_is_valid(res, sizeof(fd)))
 	{
@@ -194,14 +108,11 @@ lo_close(PGconn *conn, int fd)
 	PGresult   *res;
 	int			retval;
 
-	if (lo_initialize(conn) < 0)
-		return -1;
-
 	fd = pg_hton32(fd);
 	argv[0] = (char *) &fd;
 
-	res = PQexecPrepared(conn, "libpq_internal_lo_close", 1,
-						 (const char *const *) argv, argLens, argFormats, 1);
+	res = PQexecParams(conn, "SELECT pg_catalog.lo_close($1::pg_catalog.int4)", 1, NULL,
+					   (const char *const *) argv, argLens, argFormats, 1);
 
 	if (lo_result_is_valid(res, sizeof(retval)))
 	{
@@ -232,9 +143,6 @@ lo_truncate(PGconn *conn, int fd, size_t len)
 	PGresult   *res;
 	int			retval;
 
-	if (lo_initialize(conn) < 0)
-		return -1;
-
 	if (PQserverVersion(conn) < 80300)
 	{
 		libpq_append_conn_error(conn, "server does not support function \"%s\"",
@@ -263,8 +171,8 @@ lo_truncate(PGconn *conn, int fd, size_t len)
 	len = pg_hton32(len);
 	argv[1] = (char *) &len;
 
-	res = PQexecPrepared(conn, "libpq_internal_lo_truncate", 2,
-						 (const char *const *) argv, argLens, argFormats, 1);
+	res = PQexecParams(conn, "SELECT pg_catalog.lo_truncate($1::pg_catalog.int4, $2::pg_catalog.int4)", 2, NULL,
+					   (const char *const *) argv, argLens, argFormats, 1);
 
 	if (lo_result_is_valid(res, sizeof(retval)))
 	{
@@ -295,9 +203,6 @@ lo_truncate64(PGconn *conn, int fd, int64_t len)
 	PGresult   *res;
 	int			retval;
 
-	if (lo_initialize(conn) < 0)
-		return -1;
-
 	if (PQserverVersion(conn) < 90300)
 	{
 		libpq_append_conn_error(conn, "server does not support function \"%s\"",
@@ -311,8 +216,8 @@ lo_truncate64(PGconn *conn, int fd, int64_t len)
 	len = pg_hton64(len);
 	argv[1] = (char *) &len;
 
-	res = PQexecPrepared(conn, "ligpq_internal_lo_truncate64", 2,
-						 (const char *const *) argv, argLens, argFormats, 1);
+	res = PQexecParams(conn, "SELECT pg_catalog.lo_truncate64($1::pg_catalog.int4, $2::pg_catalog.int8)", 2, NULL,
+					   (const char *const *) argv, argLens, argFormats, 1);
 
 	if (lo_result_is_valid(res, sizeof(retval)))
 	{
@@ -343,9 +248,6 @@ lo_read(PGconn *conn, int fd, char *buf, size_t len)
 	int			argFormats[] = {1, 1};
 	PGresult   *res;
 
-	if (lo_initialize(conn) < 0)
-		return -1;
-
 	/*
 	 * Long ago, somebody thought it'd be a good idea to declare this function
 	 * as taking size_t ... but the underlying backend function only accepts a
@@ -364,8 +266,8 @@ lo_read(PGconn *conn, int fd, char *buf, size_t len)
 	len = pg_hton32(len);
 	argv[1] = (char *) &len;
 
-	res = PQexecPrepared(conn, "libpq_internal_loread", 2,
-						 (const char *const *) argv, argLens, argFormats, 1);
+	res = PQexecParams(conn, "SELECT pg_catalog.loread($1::pg_catalog.int4, $2::pg_catalog.int4)", 2, NULL,
+					   (const char *const *) argv, argLens, argFormats, 1);
 
 	if (lo_result_is_valid(res, -1))
 	{
@@ -401,9 +303,6 @@ lo_write(PGconn *conn, int fd, const char *buf, size_t len)
 	PGresult   *res;
 	int			retval;
 
-	if (lo_initialize(conn) < 0)
-		return -1;
-
 	/*
 	 * Long ago, somebody thought it'd be a good idea to declare this function
 	 * as taking size_t ... but the underlying backend function only accepts a
@@ -421,8 +320,8 @@ lo_write(PGconn *conn, int fd, const char *buf, size_t len)
 
 	argv[1] = unconstify(char *, buf);
 
-	res = PQexecPrepared(conn, "libpq_internal_lowrite", 2,
-						 (const char *const *) argv, argLens, argFormats, 1);
+	res = PQexecParams(conn, "SELECT pg_catalog.lowrite($1::pg_catalog.int4, $2::pg_catalog.bytea)", 2, NULL,
+					   (const char *const *) argv, argLens, argFormats, 1);
 
 	if (lo_result_is_valid(res, sizeof(retval)))
 	{
@@ -450,9 +349,6 @@ lo_lseek(PGconn *conn, int fd, int offset, int whence)
 	PGresult   *res;
 	int			retval;
 
-	if (lo_initialize(conn) < 0)
-		return -1;
-
 	fd = pg_hton32(fd);
 	argv[0] = (char *) &fd;
 
@@ -462,8 +358,8 @@ lo_lseek(PGconn *conn, int fd, int offset, int whence)
 	whence = pg_hton32(whence);
 	argv[2] = (char *) &whence;
 
-	res = PQexecPrepared(conn, "libpq_internal_lseek", 3,
-						 (const char *const *) argv, argLens, argFormats, 1);
+	res = PQexecParams(conn, "SELECT pg_catalog.lseek($1::pg_catalog.int4, $2::pg_catalog.int4, $3::pg_catalog.int4)", 3, NULL,
+					   (const char *const *) argv, argLens, argFormats, 1);
 
 	if (lo_result_is_valid(res, sizeof(retval)))
 	{
@@ -491,9 +387,6 @@ lo_lseek64(PGconn *conn, int fd, int64_t offset, int whence)
 	PGresult   *res;
 	int64		retval;
 
-	if (lo_initialize(conn) < 0)
-		return -1;
-
 	if (PQserverVersion(conn) < 90300)
 	{
 		libpq_append_conn_error(conn, "server does not support function \"%s\"",
@@ -510,8 +403,8 @@ lo_lseek64(PGconn *conn, int fd, int64_t offset, int whence)
 	whence = pg_hton32(whence);
 	argv[2] = (char *) &whence;
 
-	res = PQexecPrepared(conn, "ligpq_internal_lo_lseek64", 3,
-						 (const char *const *) argv, argLens, argFormats, 1);
+	res = PQexecParams(conn, "SELECT pg_catalog.lo_lseek64($1::pg_catalog.int4, $2::pg_catalog.int8, $3::pg_catalog.int4)", 3, NULL,
+					   (const char *const *) argv, argLens, argFormats, 1);
 	if (lo_result_is_valid(res, sizeof(retval)))
 	{
 		memcpy(&retval, PQgetvalue(res, 0, 0), sizeof(retval));
@@ -542,14 +435,11 @@ lo_creat(PGconn *conn, int mode)
 	PGresult   *res;
 	int			retval;
 
-	if (lo_initialize(conn) < 0)
-		return InvalidOid;
-
 	mode = pg_hton32(mode);
 	argv[0] = (char *) &mode;
 
-	res = PQexecPrepared(conn, "libpq_internal_lo_creat", 1,
-						 (const char *const *) argv, argLens, argFormats, 1);
+	res = PQexecParams(conn, "SELECT pg_catalog.lo_creat($1::pg_catalog.int4)", 1, NULL,
+					   (const char *const *) argv, argLens, argFormats, 1);
 
 	if (lo_result_is_valid(res, sizeof(retval)))
 	{
@@ -581,9 +471,6 @@ lo_create(PGconn *conn, Oid lobjId)
 	PGresult   *res;
 	int			retval;
 
-	if (lo_initialize(conn) < 0)
-		return InvalidOid;
-
 	if (PQserverVersion(conn) < 80100)
 	{
 		libpq_append_conn_error(conn, "server does not support function \"%s\"",
@@ -594,8 +481,8 @@ lo_create(PGconn *conn, Oid lobjId)
 	lobjId = pg_hton32(lobjId);
 	argv[0] = (char *) &lobjId;
 
-	res = PQexecPrepared(conn, "libpq_internal_lo_create", 1,
-						 (const char *const *) argv, argLens, argFormats, 1);
+	res = PQexecParams(conn, "SELECT pg_catalog.lo_create($1::pg_catalog.oid)", 1, NULL,
+					   (const char *const *) argv, argLens, argFormats, 1);
 
 	if (lo_result_is_valid(res, sizeof(retval)))
 	{
@@ -624,14 +511,11 @@ lo_tell(PGconn *conn, int fd)
 	int			argFormats[] = {1};
 	PGresult   *res;
 
-	if (lo_initialize(conn) < 0)
-		return -1;
-
 	fd = pg_hton32(fd);
 	argv[0] = (char *) &fd;
 
-	res = PQexecPrepared(conn, "libpq_internal_lo_tell", 1,
-						 (const char *const *) argv, argLens, argFormats, 1);
+	res = PQexecParams(conn, "SELECT pg_catalog.lo_tell($1::pg_catalog.int4)", 1, NULL,
+					   (const char *const *) argv, argLens, argFormats, 1);
 
 	if (lo_result_is_valid(res, sizeof(retval)))
 	{
@@ -659,9 +543,6 @@ lo_tell64(PGconn *conn, int fd)
 	int			argFormats[] = {1};
 	PGresult   *res;
 
-	if (lo_initialize(conn) < 0)
-		return -1;
-
 	if (PQserverVersion(conn) < 90300)
 	{
 		libpq_append_conn_error(conn, "server does not support functions \"%s\"",
@@ -672,8 +553,8 @@ lo_tell64(PGconn *conn, int fd)
 	fd = pg_hton32(fd);
 	argv[0] = (char *) &fd;
 
-	res = PQexecPrepared(conn, "libpq_internal_lo_tell64", 1,
-						 (const char *const *) argv, argLens, argFormats, 1);
+	res = PQexecParams(conn, "SELECT pg_catalog.lo_tell64($1::pg_catalog.int4)", 1, NULL,
+					   (const char *const *) argv, argLens, argFormats, 1);
 
 	if (lo_result_is_valid(res, sizeof(retval)))
 	{
@@ -702,14 +583,11 @@ lo_unlink(PGconn *conn, Oid lobjId)
 	PGresult   *res;
 	int			retval;
 
-	if (lo_initialize(conn) < 0)
-		return -1;
-
 	lobjId = pg_hton32(lobjId);
 	argv[0] = (char *) &lobjId;
 
-	res = PQexecPrepared(conn, "libpq_internal_lo_unlink", 1,
-						 (const char *const *) argv, argLens, argFormats, 1);
+	res = PQexecParams(conn, "SELECT pg_catalog.lo_unlink($1::pg_catalog.oid)", 1, NULL,
+					   (const char *const *) argv, argLens, argFormats, 1);
 
 	if (lo_result_is_valid(res, sizeof(retval)))
 	{
@@ -938,65 +816,3 @@ lo_export(PGconn *conn, Oid lobjId, const char *filename)
 
 	return result;
 }
-
-
-/*
- * lo_initialize
- *
- * Initialize for a new large-object operation on an existing connection.
- * Return 0 if OK, -1 on failure.
- *
- * If we haven't previously done so, we prepared statements for all the
- * functions that are required for large object operations.
- */
-static int
-lo_initialize(PGconn *conn)
-{
-	/* Nothing we can do with no connection */
-	if (conn == NULL)
-		return -1;
-
-	/* Since this is the beginning of a query cycle, reset the error state */
-	pqClearConnErrorState(conn);
-
-	/* Nothing else to do if we already prepared the statements */
-	if (conn->lobjprepared)
-		return 0;
-
-	for (int i = 0; i < lengthof(lobjfuncs); i++)
-	{
-		PGresult   *res;
-		ExecStatusType status;
-		PQExpBufferData pname;
-		PQExpBufferData pquery;
-
-		if (PQserverVersion(conn) < lobjfuncs[i].version)
-			continue;
-
-		initPQExpBuffer(&pname);
-		initPQExpBuffer(&pquery);
-
-		appendPQExpBuffer(&pname, "libpq_internal_%s",
-						  lobjfuncs[i].name);
-		appendPQExpBuffer(&pquery, "SELECT pg_catalog.%s(%s)",
-						  lobjfuncs[i].name, lobjfuncs[i].args);
-
-		res = PQprepare(conn, pname.data, pquery.data,
-						lobjfuncs[i].nargs, NULL);
-		status = PQresultStatus(res);
-		if (res)
-			PQclear(res);
-
-		termPQExpBuffer(&pname);
-		termPQExpBuffer(&pquery);
-
-		if (status == PGRES_COMMAND_OK)
-			continue;
-
-		libpq_append_conn_error(conn, "query to prepare large object statements failed");
-		return -1;
-	}
-
-	conn->lobjprepared = true;
-	return 0;
-}
diff --git a/src/interfaces/libpq/libpq-int.h b/src/interfaces/libpq/libpq-int.h
index 9dd0f42b6b7..cf968f1519b 100644
--- a/src/interfaces/libpq/libpq-int.h
+++ b/src/interfaces/libpq/libpq-int.h
@@ -544,7 +544,6 @@ struct pg_conn
 	PGTernaryBool in_hot_standby;	/* in_hot_standby */
 	PGVerbosity verbosity;		/* error/notice message verbosity */
 	PGContextVisibility show_context;	/* whether to show CONTEXT field */
-	bool		lobjprepared;	/* whether LO statements have been prepared */
 	pg_prng_state prng_state;	/* prng state for load balancing connections */
 
 
-- 
2.50.1 (Apple Git-155)

