commander: add preflight check for hardfault files on SD card

src/modules/commander/HealthAndArmingChecks/checks/sdcardCheck.cpp

@@ -32,6 +32,8 @@
  ****************************************************************************/
 
 #include "sdcardCheck.hpp"
+#include <dirent.h>
+#include <string.h>
 
 #ifdef __PX4_DARWIN
 #include <sys/param.h>
@@ -42,38 +44,85 @@
 
 void SdCardChecks::checkAndReport(const Context &context, Report &reporter)
 {
-	if (_param_com_arm_sdcard.get() <= 0) {
-		return;
-	}
+	if (_param_com_arm_sdcard.get() > 0) {
 
-	struct statfs statfs_buf;
+		struct statfs statfs_buf;
 
-	if (!_sdcard_detected && statfs(PX4_STORAGEDIR, &statfs_buf) == 0) {
-		// on NuttX we get a data block count f_blocks and byte count per block f_bsize if an SD card is inserted
-		_sdcard_detected = (statfs_buf.f_blocks > 0) && (statfs_buf.f_bsize > 0);
-	}
-
-	if (!_sdcard_detected) {
-		NavModes affected_modes{NavModes::None};
-
-		if (_param_com_arm_sdcard.get() == 2) {
-			// disallow arming without sd card
-			affected_modes = NavModes::All;
+		if (!_sdcard_detected && statfs(PX4_STORAGEDIR, &statfs_buf) == 0) {
+			// on NuttX we get a data block count f_blocks and byte count per block f_bsize if an SD card is inserted
+			_sdcard_detected = (statfs_buf.f_blocks > 0) && (statfs_buf.f_bsize > 0);
 		}
 
+		if (!_sdcard_detected) {
+			NavModes affected_modes{NavModes::None};
+
+			if (_param_com_arm_sdcard.get() == 2) {
+				// disallow arming without sd card
+				affected_modes = NavModes::All;
+			}
+
+			/* EVENT
+			 * @description
+			 * Insert an SD Card to the autopilot and reboot the system.
+			 *
+			 * <profile name="dev">
+			 * This check can be configured via <param>COM_ARM_SDCARD</param> parameter.
+			 * </profile>
+			 */
+			reporter.armingCheckFailure(affected_modes, health_component_t::system,
+						    events::ID("check_missing_fmu_sdcard"),
+						    events::Log::Error, "Missing FMU SD Card");
+
+			if (reporter.mavlink_log_pub()) {
+				mavlink_log_critical(reporter.mavlink_log_pub(), "Preflight Fail: Missing FMU SD Card");
+			}
+		}
+	}
+
+#ifdef __PX4_NUTTX
+	// Check for hardfault files
+
+	if (!_hardfault_checked_once && _param_com_arm_hardfault_check.get()) {
+		_hardfault_checked_once = true;
+
+		DIR *dp = opendir(PX4_STORAGEDIR);
+
+		if (dp != nullptr) {
+
+			struct dirent *result;
+
+			while ((result = readdir(dp)) && !_hardfault_file_present) {
+
+				// Check for pattern fault_*.log
+				if (strncmp("fault_", result->d_name, 6) == 0 && strcmp(result->d_name + strlen(result->d_name) - 4, ".log") == 0) {
+					_hardfault_file_present = true;
+				}
+			}
+
+			closedir(dp);
+		}
+	}
+
+	if (_hardfault_file_present && _param_com_arm_hardfault_check.get()) {
 		/* EVENT
 		 * @description
-		 * Insert an SD Card to the autopilot and reboot the system.
+		 * The SD card contains crash dump files, service the vehicle before continuing to fly.
 		 *
 		 * <profile name="dev">
-		 * This check can be configured via <param>COM_ARM_SDCARD</param> parameter.
+		 * Check how to debug hardfaults on <a>https://docs.px4.io/main/en/debug/gdb_debugging.html#hard-fault-debugging</a>.
+		 * When completed, remove the files 'fault_*.log' on the SD card.
+		 *
+		 * This check can be configured via <param>COM_ARM_HFLT_CHK</param> parameter.
 		 * </profile>
 		 */
-		reporter.armingCheckFailure(affected_modes, health_component_t::system, events::ID("check_missing_fmu_sdcard"),
-					    events::Log::Error, "Missing FMU SD Card");
+		reporter.healthFailure(NavModes::All, health_component_t::system,
+				       events::ID("check_hardfault_present"),
+				       events::Log::Error, "Crash dumps present on SD card");
 
 		if (reporter.mavlink_log_pub()) {
-			mavlink_log_critical(reporter.mavlink_log_pub(), "Preflight Fail: Missing FMU SD Card");
+			mavlink_log_critical(reporter.mavlink_log_pub(), "Preflight Fail: Crash dumps present on SD, vehicle needs service");
 		}
 	}
+
+#endif /* __PX4_NUTTX */
 }

src/modules/commander/HealthAndArmingChecks/checks/sdcardCheck.hpp

@@ -46,7 +46,13 @@ public:
 private:
 	bool _sdcard_detected{false};
 
+#ifdef __PX4_NUTTX
+	bool _hardfault_checked_once {false};
+	bool _hardfault_file_present{false};
+#endif
+
 	DEFINE_PARAMETERS_CUSTOM_PARENT(HealthAndArmingCheckBase,
-					(ParamInt<px4::params::COM_ARM_SDCARD>) _param_com_arm_sdcard
+					(ParamInt<px4::params::COM_ARM_SDCARD>) _param_com_arm_sdcard,
+					(ParamBool<px4::params::COM_ARM_HFLT_CHK>) _param_com_arm_hardfault_check
 				       )
 };

src/modules/commander/commander_params.c

@@ -1010,6 +1010,17 @@ PARAM_DEFINE_INT32(COM_ARM_ARSP_EN, 1);
  */
 PARAM_DEFINE_INT32(COM_ARM_SDCARD, 1);
 
+/**
+ * Enable FMU SD card hardfault detection check
+ *
+ * This check detects if there are hardfault files present on the
+ * SD card. If so, and the parameter is enabled, arming is prevented.
+ *
+ * @group Commander
+ * @boolean
+ */
+PARAM_DEFINE_INT32(COM_ARM_HFLT_CHK, 1);
+
 /**
  * Enforced delay between arming and further navigation
  *