Fix CRC computation in ISM

src/core/system_parameters/galileo_ism.cc

@@ -15,7 +15,6 @@
  */
 
 #include "galileo_ism.h"
-#include <boost/crc.hpp>
 #include <boost/dynamic_bitset.hpp>
 #include <algorithm>
 #include <vector>
@@ -176,15 +175,12 @@ uint16_t Galileo_ISM::get_Tvalidity_hours() const
 }
 
 
-bool Galileo_ISM::check_ism_crc(const std::bitset<GALILEO_DATA_JK_BITS>& bits) const
+bool Galileo_ISM::check_ism_crc(const std::bitset<GALILEO_DATA_JK_BITS>& bits)
 {
     boost::dynamic_bitset<unsigned char> frame_bits(bits.to_string().substr(0, GALILEO_ISM_CRC_DATA_BITS));
-
     std::vector<unsigned char> bytes;
     boost::to_block_range(frame_bits, std::back_inserter(bytes));
     std::reverse(bytes.begin(), bytes.end());
-
-    boost::crc_optimal<32, 0xC0A0A0D5, 0xFFFFFFFF, 0xFFFFFFFF, true, true> crc32_ism;
     crc32_ism.process_bytes(bytes.data(), GALILEO_ISM_CRC_DATA_BYTES);
     const uint32_t crc_computed = crc32_ism.checksum();
     if (this->ism_crc == crc_computed)
@@ -196,33 +192,9 @@ bool Galileo_ISM::check_ism_crc(const std::bitset<GALILEO_DATA_JK_BITS>& bits) c
 }
 
 
-bool Galileo_ISM::ism_apply_to_sat(uint32_t prn) const
+uint32_t Galileo_ISM::compute_crc(const std::vector<uint8_t>& data)
 {
-    if (prn == 0 || prn > 63)
+    crc32_ism.process_bytes(data.data(), data.size());
-        {
+    uint32_t result = crc32_ism.checksum();
-            return false;
+    return result;
-        }
-    std::bitset<32> bs(this->ism_mask);
-    if (this->ism_mask_msb == 0)
-        {
-            if (prn <= 32)
-                {
-                    return bs[prn - 1];
-                }
-            else
-                {
-                    return false;
-                }
-        }
-    else
-        {
-            if (prn > 32)
-                {
-                    return bs[prn - 32];
-                }
-            else
-                {
-                    return false;
-                }
-        }
 }

src/core/system_parameters/galileo_ism.h

@@ -19,9 +19,11 @@
 #define GNSS_SDR_GALILEO_ISM_H
 
 #include "Galileo_INAV.h"
+#include <boost/crc.hpp>
 #include <bitset>
 #include <cstdint>
 #include <unordered_map>
+#include <vector>
 
 /** \addtogroup Core
  * \{ */
@@ -41,7 +43,7 @@ public:
     /*!
      * Default constructor
      */
-    Galileo_ISM() = default;
+    Galileo_ISM() : crc32_ism(0x814141AB, 0, 0, false, false) {};
 
     void set_ism_constellation_id(uint8_t const_id);
     void set_ism_service_level_id(uint8_t sl_id);
@@ -57,19 +59,21 @@ public:
     void set_ism_Tvalidity(uint8_t tvalidity);
     void set_ism_crc(uint32_t crc);
 
-    bool check_ism_crc(const std::bitset<GALILEO_DATA_JK_BITS>& bits) const;  //!< Requires ism_crc to be already set
+    bool check_ism_crc(const std::bitset<GALILEO_DATA_JK_BITS>& bits);
-    bool ism_apply_to_sat(uint32_t prn) const;                                //!< Returns true if ISM parameters apply to the prn satellite, false otherwise
 
-    double get_pconst_value() const;       //!< A priori constellation fault probability
+    double get_pconst_value() const;
-    double get_psat_value() const;         //!< A priori satellite fault probability
+    double get_psat_value() const;
-    float get_ura_m() const;               //!< User Range Accuracy, in m, used for integrity
+    float get_ura_m() const;
-    float get_ure_m() const;               //!< User Range Error, in m, used for accuracy
+    float get_ure_m() const;
-    float get_bnom_m() const;              //!< Maximum nominal bias for a satellite, in m
+    float get_bnom_m() const;
-    uint16_t get_WN_ISM() const;           //!< ISM Week Number, in weeks
+    uint16_t get_WN_ISM() const;
-    uint16_t get_t0_ISM() const;           //!< ISM Time of Week, in seconds
+    uint16_t get_t0_ISM() const;
-    uint16_t get_Tvalidity_hours() const;  //!< Validity duration of ISM content, in hours
+    uint16_t get_Tvalidity_hours() const;
+    uint32_t compute_crc(const std::vector<uint8_t>& data);
 
 private:
+    boost::crc_basic<32> crc32_ism;
+
     // ICD 2.1 Table 97
     std::unordered_map<uint8_t, double> ISM_PCONST_MAP = {
         {0, 1.0e-8},
@@ -146,7 +150,6 @@ private:
         {14, 3.75},
         {15, 4.00}};
 
-
     // ICD 2.1 Table 101
     std::unordered_map<uint8_t, float> ISM_BNOM_MAP = {
         {0, 0.0},
@@ -166,7 +169,6 @@ private:
         {14, 2.0},
         {15, 2.4}};
 
-
     // ICD 2.1 Table 102
     std::unordered_map<uint8_t, uint16_t> ISM_TVALIDITY_MAP = {
         {0, 1},

src/tests/test_main.cc

@@ -18,19 +18,59 @@
 #include "concurrent_map.h"
 #include "concurrent_queue.h"
 #include "gps_acq_assist.h"
+#include <gtest/gtest.h>
+#include <fstream>
+#include <iostream>
+#include <ostream>
+#include <string>
+
+#if USE_GLOG_AND_GFLAGS
 #include <gflags/gflags.h>
 #include <glog/logging.h>
-#include <gtest/gtest.h>
-#include <iostream>
-
 #if GFLAGS_OLD_NAMESPACE
 namespace gflags
 {
 using namespace google;
 }
+DECLARE_string(log_dir);
+#endif
+#else
+#include "gnss_sdr_flags.h"
+#include <absl/flags/flag.h>
+#include <absl/flags/parse.h>
+#include <absl/log/flags.h>
+#include <absl/log/globals.h>
+#include <absl/log/initialize.h>
+#include <absl/log/log.h>
+#include <absl/log/log_sink.h>
+#include <absl/log/log_sink_registry.h>
+
+class TestingLogSink : public absl::LogSink
+{
+public:
+    TestingLogSink()
+    {
+        if (!absl::GetFlag(FLAGS_log_dir).empty())
+            {
+                filename = std::string(absl::GetFlag(FLAGS_log_dir) + "/run_tests.log");
+            }
+        else
+            {
+                filename = std::string(GetTempDir() + "/run_tests.log");
+            }
+        logfile.open(filename);
+    }
+    void Send(const absl::LogEntry &entry) override
+    {
+        logfile << entry.text_message_with_prefix_and_newline() << std::flush;
+    }
+
+private:
+    std::ofstream logfile;
+    std::string filename;
+};
 #endif
 
-DECLARE_string(log_dir);
 
 #if UNIT_TESTING_MINIMAL
 #include "unit-tests/arithmetic/matio_test.cc"
@@ -95,9 +135,6 @@ DECLARE_string(log_dir);
 #include "unit-tests/system-parameters/glonass_gnav_ephemeris_test.cc"
 #include "unit-tests/system-parameters/glonass_gnav_nav_message_test.cc"
 #include "unit-tests/system-parameters/has_decoding_test.cc"
-#include "unit-tests/system-parameters/galileo_ism_test.cc"
-
-
 
 #ifndef EXCLUDE_TESTS_REQUIRING_BINARIES
 #include "unit-tests/control-plane/control_thread_test.cc"
@@ -177,8 +214,15 @@ int main(int argc, char **argv)
     catch (...)
         {
         }  // catch the "testing::internal::<unnamed>::ClassUniqueToAlwaysTrue" from gtest
+#if USE_GLOG_AND_GFLAGS
     gflags::ParseCommandLineFlags(&argc, &argv, true);
     google::InitGoogleLogging(argv[0]);
+#else
+    absl::ParseCommandLine(argc, argv);
+    absl::LogSink *testLogSink = new TestingLogSink;
+    absl::AddLogSink(testLogSink);
+    absl::InitializeLog();
+#endif
     try
         {
             res = RUN_ALL_TESTS();
@@ -187,6 +231,10 @@ int main(int argc, char **argv)
         {
             LOG(WARNING) << "Unexpected catch";
         }
+#if USE_GLOG_AND_GFLAGS
     gflags::ShutDownCommandLineFlags();
+#else
+    absl::FlushLogSinks();
+#endif
     return res;
 }

src/tests/unit-tests/system-parameters/galileo_ism_test.cc

@@ -0,0 +1,43 @@
+/*!
+ * \file galileo_ism_test.cc
+ * \brief Tests for Galileo Integrity Support Message
+ * \author Carles Fernandez-Prades, 2024. cfernandez(at)cttc.es
+ *
+ *
+ * -----------------------------------------------------------------------------
+ *
+ * GNSS-SDR is a Global Navigation Satellite System software-defined receiver.
+ * This file is part of GNSS-SDR.
+ *
+ * Copyright (C) 2010-2023  (see AUTHORS file for a list of contributors)
+ * SPDX-License-Identifier: GPL-3.0-or-later
+ *
+ * -----------------------------------------------------------------------------
+ */
+
+#include "galileo_ism.h"
+#include <gtest/gtest.h>
+#include <algorithm>
+#include <bitset>
+#include <vector>
+
+TEST(GalileoISMTest, CRC)
+{
+    Galileo_ISM gal_ism{};
+    uint32_t expected_crc = 3002390191;
+    std::bitset<96> input{"010110000010101010101010101010101010101010101010101010101010101010101010101010101010101010101010"};
+    std::vector<uint8_t> data_bytes;
+    for (size_t i = 0; i < input.size(); i += 8)
+        {
+            std::bitset<8> byte;
+            for (size_t j = 0; j < 8; j++)
+                {
+                    byte[j] = input[i + j];
+                }
+            data_bytes.push_back(static_cast<uint8_t>(byte.to_ulong()));
+        }
+
+    std::reverse(data_bytes.begin(), data_bytes.end());
+    auto computed_crc = gal_ism.compute_crc(data_bytes);
+    EXPECT_TRUE(computed_crc == expected_crc);
+}