From 4b587603b3c80e1dbe42390f59d942e52cfb68a2 Mon Sep 17 00:00:00 2001
From: Leith Bade <leith@mapbox.com>
Date: Wed, 16 Sep 2015 12:45:46 +1000
Subject: [PATCH] Create SharedSQLiteCache

---
 android/cpp/native_map_view.cpp          |  4 ++--
 include/mbgl/android/native_map_view.hpp |  2 +-
 include/mbgl/storage/sqlite_cache.hpp    | 10 ++++++++++
 platform/default/sqlite_cache.cpp        | 12 ++++++++++++
 4 files changed, 25 insertions(+), 3 deletions(-)

diff --git a/android/cpp/native_map_view.cpp b/android/cpp/native_map_view.cpp
index f38513b32..9ffb083ec 100644
--- a/android/cpp/native_map_view.cpp
+++ b/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");
 
diff --git a/include/mbgl/android/native_map_view.hpp b/include/mbgl/android/native_map_view.hpp
index d5606ae37..4033c628b 100644
--- a/include/mbgl/android/native_map_view.hpp
+++ b/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;
 
diff --git a/include/mbgl/storage/sqlite_cache.hpp b/include/mbgl/storage/sqlite_cache.hpp
index 65328652f..3054b6c73 100644
--- a/include/mbgl/storage/sqlite_cache.hpp
+++ b/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
diff --git a/platform/default/sqlite_cache.cpp b/platform/default/sqlite_cache.cpp
index 9d5d0541e..8863c151e 100644
--- a/platform/default/sqlite_cache.cpp
+++ b/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;
+
 }