unite process/shared_memory datafacades into a single type using an allocator scheme

src/engine/datafacade/process_memory_allocator.cpp

@@ -0,0 +1,33 @@
+#include "engine/datafacade/process_memory_allocator.hpp"
+#include "storage/storage.hpp"
+
+#include "boost/assert.hpp"
+
+namespace osrm
+{
+namespace engine
+{
+namespace datafacade
+{
+
+ProcessMemoryAllocator::ProcessMemoryAllocator(const storage::StorageConfig &config)
+{
+    storage::Storage storage(config);
+
+    // Calculate the layout/size of the memory block
+    internal_layout = std::make_unique<storage::DataLayout>();
+    storage.PopulateLayout(*internal_layout);
+
+    // Allocate the memory block, then load data from files into it
+    internal_memory = std::make_unique<char[]>(internal_layout->GetSizeOfLayout());
+    storage.PopulateData(*internal_layout, internal_memory.get());
+}
+
+ProcessMemoryAllocator::~ProcessMemoryAllocator() {}
+
+storage::DataLayout &ProcessMemoryAllocator::GetLayout() { return *internal_layout.get(); }
+char *ProcessMemoryAllocator::GetMemory() { return internal_memory.get(); }
+
+} // namespace datafacade
+} // namespace engine
+} // namespace osrm