started working on ini parser

tier2/filesystem.cpp

@@ -0,0 +1,104 @@
+#include "tier2/ifilesystem.h"
+#include "tier1/interface.h"
+#include "tier0/lib.h"
+
+size_t IFileHandle::Write( const void *pData, size_t nDataSize )
+{
+	return m_pFileSystem->Write(this, pData, nDataSize);
+}
+
+size_t IFileHandle::Read( void *pData, size_t nDataSize )
+{
+	return m_pFileSystem->Read(this, pData, nDataSize);
+}
+
+size_t IFileHandle::Seek( ESeekMode eSeekMode, size_t nOffset )
+{
+	return m_pFileSystem->Seek(this, eSeekMode, nOffset);	
+}
+
+size_t IFileHandle::Tell( void )
+{
+	return m_pFileSystem->Tell(this);
+}
+
+size_t IFileHandle::Size( void )
+{
+	return m_pFileSystem->Size(this);
+}
+
+void IFileHandle::Close( void )
+{
+	m_pFileSystem->Close(this);
+}
+
+
+class CFileSystem : public IFileSystem
+{
+public:
+	virtual void Init() override {
+	};
+	virtual void Shutdown() override {
+
+	};
+
+	virtual IFileHandle *Open( const char *szFileName, int eOpCode ) override 
+	{
+		IFileSystem *pFileSystem;
+		IFileHandle *pHandle = NULL;
+
+		for ( pFileSystem = g_pFileSystems; pFileSystem; pFileSystem = pFileSystem->m_pNext )
+		{
+			pHandle = pFileSystem->Open(szFileName, eOpCode);
+			if (pHandle) return pHandle;
+		}
+
+		return NULL;
+	}
+
+	virtual size_t Write( IFileHandle *pFile, const void *pData, size_t nDataSize ) override
+	{
+		return pFile->Write(pData, nDataSize);
+	}
+
+	virtual size_t Read( IFileHandle *pFile, void *pData, size_t nDataSize ) override
+	{
+		return pFile->Read(pData, nDataSize);
+	}	
+
+	virtual size_t Seek( IFileHandle *pFile, ESeekMode eSeekMode, size_t nOffset ) override
+	{
+		return pFile->Seek(eSeekMode, nOffset);
+	}
+
+	virtual size_t Tell( IFileHandle *pFile ) override
+	{
+		return pFile->Tell();
+	}
+	virtual size_t Size( IFileHandle *pFile ) override
+	{
+		return pFile->Size();
+	}
+	virtual void Close( IFileHandle *pFile ) override
+	{
+
+	}
+};
+
+
+static CFileSystem s_fileSystem;
+IFileSystem *filesystem = &s_fileSystem;
+
+IFileSystem *g_pFileSystems;
+
+CFileSystemRegistry::CFileSystemRegistry( InstantiateFileSystemFn fn, const char *szFileSystem )
+{
+	IFileSystem *pFileSystem = fn();
+	pFileSystem->RegisterFileSystem();
+}
+
+void IFileSystem::RegisterFileSystem()
+{
+	m_pNext = g_pFileSystems;
+	g_pFileSystems = this;
+};