Mounting directories (#492)

* Create CMountDirectoryArchive.h

* Update CMountDirectoryArchive.h

* changed variable name and func to get relative path

Author: Hazardu

include/nbl/system/IFileArchive.h

@@ -64,10 +64,10 @@ class IFileArchive : public core::IReferenceCounted
 		};
 
 		//
-		core::SRange<const SListEntry> listAssets() const {return {m_items.data(),m_items.data()+m_items.size()};}
+		virtual core::SRange<const SListEntry> listAssets() const {return {m_items.data(),m_items.data()+m_items.size()};}
 
 		// List all files and directories in a specific dir of the archive
-		core::SRange<const SListEntry> listAssets(const path& asset_path) const;
+		virtual core::SRange<const SListEntry> listAssets(const path& asset_path) const;
 
 		//
 		virtual core::smart_refctd_ptr<IFile> getFile(const path& pathRelativeToArchive, const std::string_view& password) = 0;
@@ -88,10 +88,10 @@ class IFileArchive : public core::IReferenceCounted
 			return &(*found);
 		}
 
-		std::mutex itemMutex; // TODO: update to readers writer lock
+		mutable std::mutex itemMutex; // TODO: update to readers writer lock
 		path m_defaultAbsolutePath;
 		// files and directories
-		core::vector<SListEntry> m_items;
+		mutable core::vector<SListEntry> m_items;
 		//
 		system::logger_opt_smart_ptr m_logger;
 };

src/nbl/system/CMountDirectoryArchive.h

@@ -0,0 +1,61 @@
+#include "nbl/system/IFileArchive.h"
+
+#include "nbl/system/IFile.h"
+
+namespace nbl::system {
+
+
+
+class CMountDirectoryArchive : public IFileArchive
+{
+    ISystem* m_system;
+
+public:
+    inline CMountDirectoryArchive(path&& _defaultAbsolutePath, system::logger_opt_smart_ptr&& logger, ISystem* system) :
+        IFileArchive(std::move(_defaultAbsolutePath), std::move(logger))
+    {
+        m_system = system;
+    }
+
+    core::smart_refctd_ptr<IFile> getFile(const path& pathRelativeToArchive, const std::string_view& password) override
+    {
+        {
+            //std::unique_lock(itemMutex); already inside `getItemFromPath`
+            if (!getItemFromPath(pathRelativeToArchive))
+                return nullptr;
+        }
+        system::ISystem::future_t<core::smart_refctd_ptr<system::IFile>> future;
+        m_system->createFile(future, m_defaultAbsolutePath / pathRelativeToArchive, system::IFile::ECF_READ);
+        if (auto file = future.acquire())
+            return *file;
+    }
+
+    core::SRange<const IFileArchive::SListEntry> listAssets(const path& asset_path) const override
+    {
+        populateItemList(asset_path);
+        return IFileArchive::listAssets(asset_path);
+    }
+    virtual core::SRange<const SListEntry> listAssets() const override {
+        populateItemList(path());
+        return IFileArchive::listAssets();
+    }
+
+    void populateItemList(const path& p) const {
+        std::unique_lock lock(itemMutex);
+        auto items = m_system->listItemsInDirectory(m_defaultAbsolutePath/p);
+        m_items.clear();
+
+        for (auto item : items)
+        {
+            if (item.has_extension())
+            {
+                auto relpath = item.lexically_relative(m_defaultAbsolutePath);
+                auto entry = SListEntry{ relpath, 0xdeadbeefu, 0xdeadbeefu, 0xdeadbeefu, EAT_NONE };
+                m_items.push_back(entry);
+            }
+        }
+        lock.unlock();
+    }
+};
+
+} //namespace nbl::system