delete of shared LocApiBase::mMsgTask may cause issues

mMsgTask is static, its delete would impact other LocApi
objects which don't know it is deleted. Added refcount
to manage this shared obj.

Change-Id: Iea81039b9cd74081c5230d6bb18ea80c2ee05916
CRs-Fixed: 2505569

3 files changed, 16 insertions, 8 deletions

diff --git a/core/LocApiBase.cpp b/core/LocApiBase.cpp
index ef204ec..14472fa 100644
--- a/core/LocApiBase.cpp
+++ b/core/LocApiBase.cpp
@@ -148,7 +148,8 @@ struct LocCloseMsg : public LocMsg {
     }
 };
 
-MsgTask* LocApiBase::mMsgTask;
+MsgTask* LocApiBase::mMsgTask = nullptr;
+volatile int32_t LocApiBase::mMsgTaskRefCount = 0;
 
 LocApiBase::LocApiBase(LOC_API_ADAPTER_EVENT_MASK_T excludedMask,
                        ContextBase* context) :
@@ -157,6 +158,7 @@ LocApiBase::LocApiBase(LOC_API_ADAPTER_EVENT_MASK_T excludedMask,
 {
     memset(mLocAdapters, 0, sizeof(mLocAdapters));
 
+    android_atomic_inc(&mMsgTaskRefCount);
     if (nullptr == mMsgTask) {
         mMsgTask = new MsgTask("LocApiMsgTask", false);
     }
@@ -230,7 +232,7 @@ void LocApiBase::addAdapter(LocAdapterBase* adapter)
     for (int i = 0; i < MAX_ADAPTERS && mLocAdapters[i] != adapter; i++) {
         if (mLocAdapters[i] == NULL) {
             mLocAdapters[i] = adapter;
-            mMsgTask->sendMsg(new LocOpenMsg(this,  adapter));
+            sendMsg(new LocOpenMsg(this,  adapter));
             break;
         }
     }
@@ -263,10 +265,10 @@ void LocApiBase::removeAdapter(LocAdapterBase* adapter)
 
             // if we have an empty list of adapters
             if (0 == i) {
-                mMsgTask->sendMsg(new LocCloseMsg(this));
+                sendMsg(new LocCloseMsg(this));
             } else {
                 // else we need to remove the bit
-                mMsgTask->sendMsg(new LocOpenMsg(this));
+                sendMsg(new LocOpenMsg(this));
             }
         }
     }
@@ -274,7 +276,7 @@ void LocApiBase::removeAdapter(LocAdapterBase* adapter)
 
 void LocApiBase::updateEvtMask()
 {
-    mMsgTask->sendMsg(new LocOpenMsg(this));
+    sendMsg(new LocOpenMsg(this));
 }
 
 void LocApiBase::updateNmeaMask(uint32_t mask)
@@ -298,7 +300,7 @@ void LocApiBase::updateNmeaMask(uint32_t mask)
         }
     };
 
-    mMsgTask->sendMsg(new LocSetNmeaMsg(this, mask));
+    sendMsg(new LocSetNmeaMsg(this, mask));
 }
 
 void LocApiBase::handleEngineUpEvent()
diff --git a/core/LocApiBase.h b/core/LocApiBase.h
index 8c885f7..6dac585 100644
--- a/core/LocApiBase.h
+++ b/core/LocApiBase.h
@@ -34,6 +34,7 @@
 #include <gps_extended.h>
 #include <LocationAPI.h>
 #include <MsgTask.h>
+#include <LocSharedLock.h>
 #include <log_util.h>
 
 namespace loc_core {
@@ -107,6 +108,7 @@ class LocApiBase {
     friend struct LocKillMsg;
     friend class ContextBase;
     static MsgTask* mMsgTask;
+    static volatile int32_t mMsgTaskRefCount;
     LocAdapterBase* mLocAdapters[MAX_ADAPTERS];
 
 protected:
@@ -121,7 +123,8 @@ protected:
     LocApiBase(LOC_API_ADAPTER_EVENT_MASK_T excludedMask,
                ContextBase* context = NULL);
     inline virtual ~LocApiBase() {
-        if (nullptr != mMsgTask) {
+        android_atomic_dec(&mMsgTaskRefCount);
+        if (nullptr != mMsgTask && 0 == mMsgTaskRefCount) {
             mMsgTask->destroy();
             mMsgTask = nullptr;
         }
@@ -132,7 +135,9 @@ protected:
 
 public:
     inline void sendMsg(const LocMsg* msg) const {
-        mMsgTask->sendMsg(msg);
+        if (nullptr != mMsgTask) {
+            mMsgTask->sendMsg(msg);
+        }
     }
     inline void destroy() {
         close();
diff --git a/utils/Makefile.am b/utils/Makefile.am
index 807916d..9a9c67e 100644
--- a/utils/Makefile.am
+++ b/utils/Makefile.am
@@ -29,6 +29,7 @@ libgps_utils_la_h_sources = \
         gps_extended.h \
         loc_gps.h \
         log_util.h \
+        LocSharedLock.h \
         LocUnorderedSetMap.h
 
 libgps_utils_la_c_sources = \