Create SharedSQLiteCache

android/cpp/native_map_view.cpp

@@ -58,8 +58,8 @@ NativeMapView::NativeMapView(JNIEnv *env, jobject obj_, float pixelRatio_, int a
       pixelRatio(pixelRatio_),
       availableProcessors(availableProcessors_),
       totalMemory(totalMemory_),
-      fileCache(mbgl::android::cachePath + "/mbgl-cache.db"),
-      fileSource(&fileCache),
+      fileCache(mbgl::SharedSQLiteCache::get(mbgl::android::cachePath + "/mbgl-cache.db")),
+      fileSource(fileCache.get()),
       map(*this, fileSource, MapMode::Continuous) {
     mbgl::Log::Debug(mbgl::Event::Android, "NativeMapView::NativeMapView");
 

include/mbgl/android/native_map_view.hpp

@@ -90,7 +90,7 @@ private:
     size_t totalMemory = 0;
 
     // Ensure these are initialised last
-    mbgl::SQLiteCache fileCache;
+    std::shared_ptr<mbgl::SQLiteCache> fileCache;
     mbgl::DefaultFileSource fileSource;
     mbgl::Map map;
 

include/mbgl/storage/sqlite_cache.hpp

@@ -26,6 +26,16 @@ private:
     const std::unique_ptr<util::Thread<Impl>> thread;
 };
 
+class SharedSQLiteCache : util::noncopyable {
+public:
+    static std::shared_ptr<SQLiteCache> get(const std::string &path = ":memory:");
+
+private:
+    SharedSQLiteCache() {}
+
+    static std::weak_ptr<SQLiteCache> masterPtr;
+};
+
 }
 
 #endif

platform/default/sqlite_cache.cpp

@@ -264,4 +264,16 @@ void SQLiteCache::Impl::refresh(const Resource& resource, int64_t expires) {
     }
 }
 
+std::shared_ptr<SQLiteCache> SharedSQLiteCache::get(const std::string &path) {
+    std::shared_ptr<SQLiteCache> temp = masterPtr.lock();
+    if (!temp) {
+        temp.reset(new SQLiteCache(path));
+        masterPtr = temp;
+    }
+
+    return temp;
+}
+
+std::weak_ptr<SQLiteCache> SharedSQLiteCache::masterPtr;
+
 }