From 82a28dc0fcc947aabd70426224f733d95212f797 Mon Sep 17 00:00:00 2001
From: Randy Mackay <rmackay9@yahoo.com>
Date: Fri, 26 Oct 2018 11:39:48 +0900
Subject: [PATCH] AP_RangeFinder: check I2C dev during detect

---
 libraries/AP_RangeFinder/AP_RangeFinder_LightWareI2C.cpp  | 4 ++++
 libraries/AP_RangeFinder/AP_RangeFinder_MaxsonarI2CXL.cpp | 4 ++++
 libraries/AP_RangeFinder/AP_RangeFinder_TeraRangerI2C.cpp | 4 ++++
 3 files changed, 12 insertions(+)

diff --git a/libraries/AP_RangeFinder/AP_RangeFinder_LightWareI2C.cpp b/libraries/AP_RangeFinder/AP_RangeFinder_LightWareI2C.cpp
index a37293eaa3..ce84ab4c88 100644
--- a/libraries/AP_RangeFinder/AP_RangeFinder_LightWareI2C.cpp
+++ b/libraries/AP_RangeFinder/AP_RangeFinder_LightWareI2C.cpp
@@ -37,6 +37,10 @@ AP_RangeFinder_LightWareI2C::AP_RangeFinder_LightWareI2C(RangeFinder::RangeFinde
 */
 AP_RangeFinder_Backend *AP_RangeFinder_LightWareI2C::detect(RangeFinder::RangeFinder_State &_state, AP_HAL::OwnPtr<AP_HAL::I2CDevice> dev)
 {
+    if (!dev) {
+        return nullptr;
+    }
+
     AP_RangeFinder_LightWareI2C *sensor
         = new AP_RangeFinder_LightWareI2C(_state, std::move(dev));
 
diff --git a/libraries/AP_RangeFinder/AP_RangeFinder_MaxsonarI2CXL.cpp b/libraries/AP_RangeFinder/AP_RangeFinder_MaxsonarI2CXL.cpp
index b5e585c666..f876353f12 100644
--- a/libraries/AP_RangeFinder/AP_RangeFinder_MaxsonarI2CXL.cpp
+++ b/libraries/AP_RangeFinder/AP_RangeFinder_MaxsonarI2CXL.cpp
@@ -51,6 +51,10 @@ AP_RangeFinder_MaxsonarI2CXL::AP_RangeFinder_MaxsonarI2CXL(RangeFinder::RangeFin
 AP_RangeFinder_Backend *AP_RangeFinder_MaxsonarI2CXL::detect(RangeFinder::RangeFinder_State &_state,
                                                              AP_HAL::OwnPtr<AP_HAL::I2CDevice> dev)
 {
+    if (!dev) {
+        return nullptr;
+    }
+
     AP_RangeFinder_MaxsonarI2CXL *sensor
         = new AP_RangeFinder_MaxsonarI2CXL(_state, std::move(dev));
     if (!sensor) {
diff --git a/libraries/AP_RangeFinder/AP_RangeFinder_TeraRangerI2C.cpp b/libraries/AP_RangeFinder/AP_RangeFinder_TeraRangerI2C.cpp
index 3816686317..327851bc8c 100644
--- a/libraries/AP_RangeFinder/AP_RangeFinder_TeraRangerI2C.cpp
+++ b/libraries/AP_RangeFinder/AP_RangeFinder_TeraRangerI2C.cpp
@@ -49,6 +49,10 @@ AP_RangeFinder_TeraRangerI2C::AP_RangeFinder_TeraRangerI2C(RangeFinder::RangeFin
 AP_RangeFinder_Backend *AP_RangeFinder_TeraRangerI2C::detect(RangeFinder::RangeFinder_State &_state,
                                                              AP_HAL::OwnPtr<AP_HAL::I2CDevice> i2c_dev)
 {
+    if (!i2c_dev) {
+        return nullptr;
+    }
+
     AP_RangeFinder_TeraRangerI2C *sensor = new AP_RangeFinder_TeraRangerI2C(_state, std::move(i2c_dev));
     if (!sensor) {
         return nullptr;