Merge pull request #874 from jean-m-cyr/master

Proper data manager restart handling

src/modules/dataman/dataman.c

@@ -416,26 +416,26 @@ static int
 _restart(dm_reset_reason reason)
 {
 	unsigned char buffer[2];
-	int offset, result = 0;
+	int offset = 0, result = 0;
 
 	/* We need to scan the entire file and invalidate and data that should not persist after the last reset */
 
 	/* Loop through all of the data segments and delete those that are not persistent */
-	offset = 0;
-
 	while (1) {
 		size_t len;
 
 		/* Get data segment at current offset */
 		if (lseek(g_task_fd, offset, SEEK_SET) != offset) {
-			result = -1;
+			/* must be at eof */
 			break;
 		}
 
 		len = read(g_task_fd, buffer, sizeof(buffer));
 
-		if (len == 0)
+		if (len != sizeof(buffer)) {
+			/* must be at eof */
 			break;
+		}
 
 		/* check if segment contains data */
 		if (buffer[0]) {
@@ -443,12 +443,12 @@ _restart(dm_reset_reason reason)
 
 			/* Whether data gets deleted depends on reset type and data segment's persistence setting */
 			if (reason == DM_INIT_REASON_POWER_ON) {
-				if (buffer[1] != DM_PERSIST_POWER_ON_RESET) {
+				if (buffer[1] > DM_PERSIST_POWER_ON_RESET) {
 					clear_entry = 1;
 				}
 
 			} else {
-				if ((buffer[1] != DM_PERSIST_POWER_ON_RESET) && (buffer[1] != DM_PERSIST_IN_FLIGHT_RESET)) {
+				if (buffer[1] > DM_PERSIST_IN_FLIGHT_RESET) {
 					clear_entry = 1;
 				}
 			}
@@ -628,6 +628,23 @@ task_main(int argc, char *argv[])
 
 	fsync(g_task_fd);
 
+	/* see if we need to erase any items based on restart type */
+	int sys_restart_val;
+	if (param_get(param_find("SYS_RESTART_TYPE"), &sys_restart_val) == OK) {
+		if (sys_restart_val == DM_INIT_REASON_POWER_ON) {
+			warnx("Power on restart");
+			_restart(DM_INIT_REASON_POWER_ON);
+		}
+		else if (sys_restart_val == DM_INIT_REASON_IN_FLIGHT) {
+			warnx("In flight restart");
+			_restart(DM_INIT_REASON_IN_FLIGHT);
+		}
+		else
+			warnx("Unknown restart");
+	}
+	else
+		warnx("Unknown restart");
+
 	/* We use two file descriptors, one for the caller context and one for the worker thread */
 	/* They are actually the same but we need to some way to reject caller request while the */
 	/* worker thread is shutting down but still processing requests */
@@ -724,7 +741,7 @@ start(void)
 		return -1;
 	}
 
-	/* wait for the thread to actuall initialize */
+	/* wait for the thread to actually initialize */
 	sem_wait(&g_init_sema);
 	sem_destroy(&g_init_sema);
 

src/modules/dataman/dataman.h

@@ -75,7 +75,8 @@ extern "C" {
 	/* The reason for the last reset */
 	typedef enum {
 		DM_INIT_REASON_POWER_ON = 0,	/* Data survives resets */
-		DM_INIT_REASON_IN_FLIGHT	/* Data survives in-flight resets only */
+		DM_INIT_REASON_IN_FLIGHT,		/* Data survives in-flight resets only */
+		DM_INIT_REASON_VOLATILE			/* Data does not survive reset */
 	} dm_reset_reason;
 
 	/* Maximum size in bytes of a single item instance */
@@ -100,7 +101,7 @@ extern "C" {
 		size_t buflen			/* Length in bytes of data to retrieve */
 	);
 
-	/* Retrieve from the data manager store */
+	/* Erase all items of this type */
 	__EXPORT int
 	dm_clear(
 		dm_item_t item			/* The item type to clear */

src/modules/systemlib/system_params.c

@@ -62,12 +62,23 @@ PARAM_DEFINE_INT32(SYS_AUTOSTART, 0);
 PARAM_DEFINE_INT32(SYS_AUTOCONFIG, 0);
 
 /**
- * Set usage of IO board
- *
- * Can be used to use a standard startup script but with a FMU only set-up. Set to 0 to force the FMU only set-up.
- *
- * @min 0
- * @max 1
- * @group System
- */
+* Set usage of IO board
+*
+* Can be used to use a standard startup script but with a FMU only set-up. Set to 0 to force the FMU only set-up.
+*
+* @min 0
+* @max 1
+* @group System
+*/
 PARAM_DEFINE_INT32(SYS_USE_IO, 1);
+
+/**
+* Set restart type
+*
+* Set by px4io to indicate type of restart
+*
+* @min 0
+* @max 2
+* @group System
+*/
+PARAM_DEFINE_INT32(SYS_RESTART_TYPE, 2);