Keep vanetza-idf in obu-firmware, so a plain clone builds the firmware

obu-firmware builds against the vanetza-idf C-ITS library, which until now
came from the colleague's microbu-esp32c5 tree beside the repository and was
not tracked here, so a clone of this repository could not build the firmware
it ships. The library alone is now part of obu-firmware, as
obu-firmware/external/vanetza-idf: their external/vanetza-idf at commit
cf4b99f, unchanged (9775 files; see its PROVENANCE.md). CMake takes it from
there by default; -DVANETZA_IDF_DIR still points the build elsewhere.

The rest of the colleague's tree (their own VAM firmware, PKI tooling,
station-link Python tools, the V2X2MAP bridge) stays out of this repository
and gitignored; nothing is pushed to their repository. NOTES.md, docs/06,
TODO.md and the pcap verifier's usage line point at the new location.

obu-firmware/external/vanetza-idf/vanetza/geonet/tests/data_request.cpp

@@ -0,0 +1,69 @@
+#include <gtest/gtest.h>
+#include <vanetza/geonet/data_request.hpp>
+#include <vanetza/units/time.hpp>
+
+using namespace vanetza::geonet;
+using vanetza::units::si::seconds;
+
+TEST(DataRequest, repetition) {
+    MIB mib;
+    DataRequest r(mib);
+    EXPECT_FALSE(!!r.repetition);
+
+    r.repetition = DataRequest::Repetition();
+    EXPECT_TRUE(!!r.repetition);
+}
+
+TEST(DataRequest, has_further_repetition) {
+    DataRequest::Repetition repetition;
+    repetition.interval = 10.0 * seconds;
+    repetition.maximum = 0.0 * seconds;
+    EXPECT_FALSE(has_further_repetition(repetition));
+
+    repetition.interval = 0.0 * seconds;
+    EXPECT_FALSE(has_further_repetition(repetition));
+
+    repetition.maximum = -10.0 * seconds;
+    repetition.interval = -15.0 * seconds;
+    EXPECT_FALSE(has_further_repetition(repetition));
+
+    repetition.maximum = 30.0 * seconds;
+    repetition.interval = 10.0 * seconds;
+    EXPECT_TRUE(has_further_repetition(repetition));
+
+    repetition.interval = 0.0 * seconds;
+    EXPECT_FALSE(has_further_repetition(repetition));
+}
+
+TEST(DataRequest, decrement_by_one) {
+    DataRequest::Repetition repetition;
+    repetition.maximum = 30.0 * seconds;
+    repetition.interval = 10.0 * seconds;
+    decrement_by_one(repetition);
+    EXPECT_DOUBLE_EQ(repetition.interval / seconds, 10.0);
+    EXPECT_DOUBLE_EQ(repetition.maximum / seconds, 20.0);
+
+    repetition.interval = 5.0 * seconds;
+    decrement_by_one(repetition);
+    EXPECT_DOUBLE_EQ(repetition.maximum / seconds, 15.0);
+
+    repetition.interval = 20.0 * seconds;
+    decrement_by_one(repetition);
+    EXPECT_DOUBLE_EQ(repetition.maximum / seconds, 0.0);
+    EXPECT_DOUBLE_EQ(repetition.interval / seconds, 20.0);
+
+    repetition.maximum = -30.0 * seconds;
+    repetition.interval = -60.0 * seconds;
+    decrement_by_one(repetition);
+    EXPECT_DOUBLE_EQ(repetition.maximum / seconds, 0.0);
+
+    repetition.maximum = -30.0 * seconds;
+    repetition.interval = -10.0 * seconds;
+    decrement_by_one(repetition);
+    EXPECT_DOUBLE_EQ(repetition.maximum / seconds, 0.0);
+
+    repetition.maximum = 30.0 * seconds;
+    repetition.interval = -10.0 * seconds;
+    decrement_by_one(repetition);
+    EXPECT_DOUBLE_EQ(repetition.maximum / seconds, 0.0);
+}