From a1c4aa6dc9ecb83dcf31c91eab3f00dee655db4f Mon Sep 17 00:00:00 2001
From: Marco Hauswirth <marco.hauswirth@auterion.com>
Date: Thu, 18 Sep 2025 17:22:18 +0200
Subject: [PATCH] * remove random lib since its not available on Nuttx * fix
 gps-stuck-failure to actually be stuck

---
 .../failure_injection/failureInjection.cpp     |  7 +++----
 .../sensor_sim_manager/SensorSimManager.cpp    | 18 ++++++++----------
 .../sensor_sim_manager/SensorSimManager.hpp    |  7 +------
 3 files changed, 12 insertions(+), 20 deletions(-)

diff --git a/src/modules/simulation/failure_injection/failureInjection.cpp b/src/modules/simulation/failure_injection/failureInjection.cpp
index fc46d70368..4e0be41e73 100644
--- a/src/modules/simulation/failure_injection/failureInjection.cpp
+++ b/src/modules/simulation/failure_injection/failureInjection.cpp
@@ -92,12 +92,13 @@ bool FailureInjection::handle_gps_failure(sensor_gps_s &gps)
 
 		}
 
+		_gps_prev = gps;
+
 	} else {
 		gps = _gps_prev;
 	}
 
 	_last_gps_timestamp = gps.timestamp;
-	_gps_prev = gps;
 
 	return true;
 }
@@ -113,7 +114,6 @@ bool FailureInjection::handle_gps_alt_failure(sensor_gps_s &gps)
 		if (_gps_alt_wrong) {
 			gps.altitude_msl_m += 100.0;
 			gps.altitude_ellipsoid_m += 100.0;
-
 		}
 
 		if (_gps_alt_drift) {
@@ -132,16 +132,15 @@ bool FailureInjection::handle_gps_alt_failure(sensor_gps_s &gps)
 			}
 
 			gps.altitude_msl_m = _gps_alt_offset;
-
 		}
 
+		_gps_prev = gps;
 
 	} else {
 		gps = _gps_prev;
 	}
 
 	_last_gps_timestamp = gps.timestamp;
-	_gps_prev = gps;
 
 	return true;
 
diff --git a/src/modules/simulation/sensor_sim_manager/SensorSimManager.cpp b/src/modules/simulation/sensor_sim_manager/SensorSimManager.cpp
index 2938cafcbb..c51d2d10c8 100644
--- a/src/modules/simulation/sensor_sim_manager/SensorSimManager.cpp
+++ b/src/modules/simulation/sensor_sim_manager/SensorSimManager.cpp
@@ -45,9 +45,7 @@ using namespace matrix;
 
 SensorSimManager::SensorSimManager() :
 	ModuleParams(nullptr),
-	ScheduledWorkItem(MODULE_NAME, px4::wq_configurations::hp_default),
-	_gen(_rd()),
-	_uniform_dist(0.0f, 1.0f)
+	ScheduledWorkItem(MODULE_NAME, px4::wq_configurations::hp_default)
 {
 	_px4_accel.set_temperature(kT1C);
 	_px4_gyro.set_temperature(kT1C);
@@ -61,7 +59,7 @@ SensorSimManager::SensorSimManager() :
 	_gps_timing = {
 		.interval_us = 125000,
 		.next_update_time = now,
-		.offset_us = static_cast<hrt_abstime>(_uniform_dist(_gen) * 125000),
+		.offset_us = static_cast<hrt_abstime>((float(rand()) / RAND_MAX) * 125000),
 		.enabled = false,
 	};
 
@@ -69,7 +67,7 @@ SensorSimManager::SensorSimManager() :
 	_baro_timing = {
 		.interval_us = 50000,
 		.next_update_time = now,
-		.offset_us = static_cast<hrt_abstime>(_uniform_dist(_gen) * 50000),
+		.offset_us = static_cast<hrt_abstime>((float(rand()) / RAND_MAX) * 50000),
 		.enabled = false,
 	};
 
@@ -77,7 +75,7 @@ SensorSimManager::SensorSimManager() :
 	_mag_timing = {
 		.interval_us = 20000,
 		.next_update_time = now,
-		.offset_us = static_cast<hrt_abstime>(_uniform_dist(_gen) * 20000),
+		.offset_us = static_cast<hrt_abstime>((float(rand()) / RAND_MAX) * 20000),
 		.enabled = false,
 	};
 
@@ -85,7 +83,7 @@ SensorSimManager::SensorSimManager() :
 	_airspeed_timing = {
 		.interval_us = 125000,
 		.next_update_time = now,
-		.offset_us = static_cast<hrt_abstime>(_uniform_dist(_gen) * 125000),
+		.offset_us = static_cast<hrt_abstime>((float(rand()) / RAND_MAX) * 125000),
 		.enabled = false,
 	};
 
@@ -93,7 +91,7 @@ SensorSimManager::SensorSimManager() :
 	_agp_timing = {
 		.interval_us = 500000,
 		.next_update_time = now,
-		.offset_us = static_cast<hrt_abstime>(_uniform_dist(_gen) * 500000),
+		.offset_us = static_cast<hrt_abstime>((float(rand()) / RAND_MAX) * 500000),
 		.enabled = false,
 	};
 
@@ -101,7 +99,7 @@ SensorSimManager::SensorSimManager() :
 	_distance_sensor_timing = {
 		.interval_us = 20000,
 		.next_update_time = now,
-		.offset_us = static_cast<hrt_abstime>(_uniform_dist(_gen) * 20000),
+		.offset_us = static_cast<hrt_abstime>((float(rand()) / RAND_MAX) * 20000),
 		.enabled = false,
 	};
 
@@ -109,7 +107,7 @@ SensorSimManager::SensorSimManager() :
 	_imu_timing = {
 		.interval_us = 4000,
 		.next_update_time = now,
-		.offset_us = static_cast<hrt_abstime>(_uniform_dist(_gen) * 4000),
+		.offset_us = static_cast<hrt_abstime>((float(rand()) / RAND_MAX) * 4000),
 		.enabled = true,
 	};
 
diff --git a/src/modules/simulation/sensor_sim_manager/SensorSimManager.hpp b/src/modules/simulation/sensor_sim_manager/SensorSimManager.hpp
index 5b25397b8d..80a095d396 100644
--- a/src/modules/simulation/sensor_sim_manager/SensorSimManager.hpp
+++ b/src/modules/simulation/sensor_sim_manager/SensorSimManager.hpp
@@ -64,7 +64,7 @@
 #include <lib/mathlib/mathlib.h>
 #include <lib/lat_lon_alt/lat_lon_alt.hpp>
 #include <parameters/param.h>
-#include <random>
+#include <px4_platform_common/px4_config.h>
 
 using namespace time_literals;
 
@@ -153,11 +153,6 @@ private:
 	perf_counter_t _imu_perf{perf_alloc(PC_ELAPSED, MODULE_NAME": imu")};
 	perf_counter_t _distance_sensor_perf{perf_alloc(PC_ELAPSED, MODULE_NAME": distance")};
 
-	// Random number generator for offsets and noise
-	std::random_device _rd;
-	std::mt19937 _gen;
-	std::uniform_real_distribution<float> _uniform_dist;
-
 	// Parameters
 	DEFINE_PARAMETERS(
 		(ParamInt<px4::params::SENS_EN_GPSSIM>) _param_sens_en_gpssim,