Add an "Append CRC32" block

lib/append_crc32_impl.h

@@ -0,0 +1,40 @@
+/*
+ * Copyright (C) 2025 Nicolas Guillaume <nicol@sguillau.me>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#ifndef INCLUDED_IEEE802_11_APPEND_CRC32_IMPL_H
+#define INCLUDED_IEEE802_11_APPEND_CRC32_IMPL_H
+
+#include <ieee802_11/append_crc32.h>
+#include <pmt/pmt.h>
+
+namespace gr {
+namespace ieee802_11 {
+
+class append_crc32_impl : public append_crc32
+{
+public:
+    append_crc32_impl(bool append);
+
+private:
+    void handle(pmt::pmt_t msg);
+
+    bool d_append;
+};
+
+}
+}
+
+#endif