From df5d702baefae7f51161d170c911cb398f418538 Mon Sep 17 00:00:00 2001
From: Anton Babushkin <anton.babushkin@me.com>
Date: Sun, 16 Mar 2014 17:03:39 +0400
Subject: [PATCH] mavlink: MavlinkOrbSubscription.update() result fixed

---
 src/modules/mavlink/mavlink_orb_subscription.cpp | 13 ++++++++-----
 src/modules/mavlink/mavlink_orb_subscription.h   | 13 +++++++------
 2 files changed, 15 insertions(+), 11 deletions(-)

diff --git a/src/modules/mavlink/mavlink_orb_subscription.cpp b/src/modules/mavlink/mavlink_orb_subscription.cpp
index 9963184683..e8f9bb75ba 100644
--- a/src/modules/mavlink/mavlink_orb_subscription.cpp
+++ b/src/modules/mavlink/mavlink_orb_subscription.cpp
@@ -78,12 +78,15 @@ MavlinkOrbSubscription::get_data()
 bool
 MavlinkOrbSubscription::update(const hrt_abstime t)
 {
-	if (_last_check != t) {
-		_last_check = t;
-		bool updated;
-		orb_check(_fd, &updated);
+	if (_last_check == t) {
+		/* already checked right now, return result of the check */
+		return _updated;
 
-		if (updated) {
+	} else {
+		_last_check = t;
+		orb_check(_fd, &_updated);
+
+		if (_updated) {
 			orb_copy(_topic, _fd, _data);
 			return true;
 		}
diff --git a/src/modules/mavlink/mavlink_orb_subscription.h b/src/modules/mavlink/mavlink_orb_subscription.h
index 42d47e96ed..8529721c03 100644
--- a/src/modules/mavlink/mavlink_orb_subscription.h
+++ b/src/modules/mavlink/mavlink_orb_subscription.h
@@ -48,7 +48,7 @@
 class MavlinkOrbSubscription
 {
 public:
-	MavlinkOrbSubscription *next;
+	MavlinkOrbSubscription *next;	/*< pointer to next subscription in list */
 
 	MavlinkOrbSubscription(const orb_id_t topic);
 	~MavlinkOrbSubscription();
@@ -66,11 +66,12 @@ public:
 	const orb_id_t get_topic();
 
 private:
-	const orb_id_t _topic;
-	int _fd;
-	bool _published;
-	void *_data;
-	hrt_abstime _last_check;
+	const orb_id_t _topic;		/*< topic metadata */
+	int _fd;					/*< subscription handle */
+	bool _published;			/*< topic was ever published */
+	void *_data;				/*< pointer to data buffer */
+	hrt_abstime _last_check;	/*< time of last check */
+	bool _updated;				/*< updated on last check */
 };