Add an "Append CRC32" block

2025-12-22 12:56:00 +01:00
parent ac55ae7ca1
commit 7e9c132dfb
11 changed files with 262 additions and 3 deletions
@@ -0,0 +1,84 @@
+/*
+ * 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/>.
+ */
+#include "append_crc32_impl.h"
+
+#include <gnuradio/block_detail.h>
+#include <gnuradio/io_signature.h>
+
+#include <boost/bind/bind.hpp>
+#include <boost/crc.hpp>
+
+#include <cstdint>
+#include <cstring>
+#include <stdexcept>
+#include <vector>
+
+using namespace gr::ieee802_11;
+
+append_crc32::sptr append_crc32::make(bool append)
+{
+    return gnuradio::get_initial_sptr(new append_crc32_impl(append));
+}
+
+append_crc32_impl::append_crc32_impl(bool append)
+    : block("append_crc32",
+            gr::io_signature::make(0, 0, 0),
+            gr::io_signature::make(0, 0, 0)),
+      d_append(append)
+{
+    message_port_register_in(pmt::mp("in"));
+    set_msg_handler(pmt::mp("in"), boost::bind(&append_crc32_impl::handle, this, boost::placeholders::_1));
+    message_port_register_out(pmt::mp("out"));
+}
+
+void append_crc32_impl::handle(pmt::pmt_t msg)
+{
+    if(pmt::is_eof_object(msg))
+    {
+        detail().get()->set_done(true);
+        return;
+    }
+
+    if(!pmt::is_pair(msg))
+        throw std::invalid_argument("append_crc32 expects PDU pair");
+
+    pmt::pmt_t meta = pmt::car(msg);
+    pmt::pmt_t blob = pmt::cdr(msg);
+
+    if(!pmt::is_blob(blob))
+        throw std::invalid_argument("append_crc32 expects blob payload");
+
+    if(!d_append)
+    {
+        message_port_pub(pmt::mp("out"), pmt::cons(meta, blob));
+        return;
+    }
+
+    size_t len = pmt::blob_length(blob);
+    const uint8_t* data = reinterpret_cast<const uint8_t*>(pmt::blob_data(blob));
+
+    boost::crc_32_type result;
+    result.process_bytes(data, len);
+    uint32_t crc = result.checksum();
+
+    std::vector<uint8_t> out(len + sizeof(uint32_t));
+    std::memcpy(out.data(), data, len);
+    std::memcpy(out.data() + len, &crc, sizeof(uint32_t));
+
+    pmt::pmt_t out_blob = pmt::make_blob(out.data(), out.size());
+    message_port_pub(pmt::mp("out"), pmt::cons(meta, out_blob));
+}