Add ability to set an int64 file control (#1298)

* Add ability to set an int64 file control

* Update documentation

* Remove duplicate err check in test

* Update sqlite3.go

Co-authored-by: rittneje <rittneje@gmail.com>

---------

Co-authored-by: rittneje <rittneje@gmail.com>

sqlite3.go

@@ -1876,6 +1876,9 @@ func (c *SQLiteConn) SetLimit(id int, newVal int) int {
 // This method is not thread-safe as the returned error code can be changed by
 // another call if invoked concurrently.
 //
+// Use SetFileControlInt64 instead if the argument for the opcode is documented
+// as a pointer to a sqlite3_int64.
+//
 // See: sqlite3_file_control, https://www.sqlite.org/c3ref/file_control.html
 func (c *SQLiteConn) SetFileControlInt(dbName string, op int, arg int) error {
 	if dbName == "" {
@@ -1893,6 +1896,34 @@ func (c *SQLiteConn) SetFileControlInt(dbName string, op int, arg int) error {
 	return nil
 }
 
+// SetFileControlInt64 invokes the xFileControl method on a given database. The
+// dbName is the name of the database. It will default to "main" if left blank.
+// The op is one of the opcodes prefixed by "SQLITE_FCNTL_". The arg argument
+// and return code are both opcode-specific. Please see the SQLite documentation.
+//
+// This method is not thread-safe as the returned error code can be changed by
+// another call if invoked concurrently.
+//
+// Only use this method if the argument for the opcode is documented as a pointer
+// to a sqlite3_int64.
+//
+// See: sqlite3_file_control, https://www.sqlite.org/c3ref/file_control.html
+func (c *SQLiteConn) SetFileControlInt64(dbName string, op int, arg int64) error {
+	if dbName == "" {
+		dbName = "main"
+	}
+
+	cDBName := C.CString(dbName)
+	defer C.free(unsafe.Pointer(cDBName))
+
+	cArg := C.sqlite3_int64(arg)
+	rv := C.sqlite3_file_control(c.db, cDBName, C.int(op), unsafe.Pointer(&cArg))
+	if rv != C.SQLITE_OK {
+		return c.lastError()
+	}
+	return nil
+}
+
 // Close the statement.
 func (s *SQLiteStmt) Close() error {
 	s.mu.Lock()

sqlite3_test.go

@@ -1864,6 +1864,32 @@ func TestSetFileControlInt(t *testing.T) {
 	})
 }
 
+func TestSetFileControlInt64(t *testing.T) {
+	const GiB = 1024 * 1024 * 1024
+
+	t.Run("", func(t *testing.T) {
+
+		sql.Register("sqlite3_FCNTL_SIZE_LIMIT", &SQLiteDriver{
+			ConnectHook: func(conn *SQLiteConn) error {
+				if err := conn.SetFileControlInt64("", SQLITE_FCNTL_SIZE_LIMIT, 4*GiB); err != nil {
+					return fmt.Errorf("Unexpected error from SetFileControlInt64(): %w", err)
+				}
+				return nil
+			},
+		})
+
+		db, err := sql.Open("sqlite3", "file:/dbname?vfs=memdb")
+		if err != nil {
+			t.Fatal("Failed to open database:", err)
+		}
+		err = db.Ping()
+		if err != nil {
+			t.Fatal("Failed to ping", err)
+		}
+		db.Close()
+	})
+}
+
 func TestNonColumnString(t *testing.T) {
 	db, err := sql.Open("sqlite3", ":memory:")
 	if err != nil {