ADD: Open version, with important changes kept out.

Signed-off-by: Amlal <amlal.elmahrouss@icloud.com>

1 files changed, 392 insertions, 0 deletions

diff --git a/dev/Kernel/KernelKit/FileMgr.h b/dev/Kernel/KernelKit/FileMgr.h
new file mode 100644
index 00000000..c78c0b97
--- /dev/null
+++ b/dev/Kernel/KernelKit/FileMgr.h
@@ -0,0 +1,392 @@
+/* -------------------------------------------
+
+	Copyright (C) 2024-2025, Amlal EL Mahrouss Labs, all rights reserved.
+
+	File: FileMgr.h
+	Purpose: Kernel file manager.
+
+------------------------------------------- */
+
+/* -------------------------------------------
+
+ Revision History:
+
+	 31/01/24: Update documentation (amlel)
+	 05/07/24: NeFS support, and fork support, updated constants and specs
+		as well.
+	18/01/25: Patches to FileStream class.
+
+ ------------------------------------------- */
+
+#ifndef INC_FILEMGR_H
+#define INC_FILEMGR_H
+
+#ifdef __FSKIT_INCLUDES_NEFS__
+#include <FSKit/NeFS.h>
+#endif // __FSKIT_INCLUDES_NEFS__
+
+#ifdef __FSKIT_INCLUDES_HPFS__
+#include <FSKit/HPFS.h>
+#endif // __FSKIT_INCLUDES_HPFS__
+
+#include <CompilerKit/CompilerKit.h>
+#include <Hints/CompilerHint.h>
+#include <KernelKit/LPC.h>
+#include <KernelKit/DebugOutput.h>
+#include <NewKit/Stream.h>
+#include <NewKit/ErrorOr.h>
+#include <KernelKit/Heap.h>
+#include <NewKit/Ref.h>
+
+/// @brief Filesystem manager, abstraction over mounted filesystem.
+/// Works like the VFS or IFS.
+
+#define kRestrictR	 "r"
+#define kRestrictRB	 "rb"
+#define kRestrictW	 "w"
+#define kRestrictWB	 "rw"
+#define kRestrictRWB "rwb"
+
+#define kRestrictMax (5U)
+
+#define node_cast(PTR) reinterpret_cast<Kernel::NodePtr>(PTR)
+
+/**
+	@note Refer to first enum.
+*/
+#define kFileOpsCount	 (4U)
+#define kFileMimeGeneric "n-application-kind/all"
+
+/** @brief invalid position. (n-pos) */
+#define kNPos (SizeT)(-1);
+
+namespace Kernel
+{
+	enum
+	{
+		kFileWriteAll	= 100,
+		kFileReadAll	= 101,
+		kFileReadChunk	= 102,
+		kFileWriteChunk = 103,
+		kFileIOCnt		= (kFileWriteChunk - kFileWriteAll) + 1,
+		// file flags
+		kFileFlagRsrc = 104,
+		kFileFlagData = 105,
+	};
+
+	typedef VoidPtr NodePtr;
+
+	/**
+	@brief Filesystem Mgr Interface class
+	@brief Used to provide common I/O for a specific filesystem.
+*/
+	class IFilesystemMgr
+	{
+	public:
+		explicit IFilesystemMgr() = default;
+		virtual ~IFilesystemMgr() = default;
+
+	public:
+		ZKA_COPY_DEFAULT(IFilesystemMgr);
+
+	public:
+		/// @brief Mounts a new filesystem into an active state.
+		/// @param interface the filesystem interface
+		/// @return
+		static bool Mount(IFilesystemMgr* interface);
+
+		/// @brief Unmounts the active filesystem
+		/// @return
+		static IFilesystemMgr* Unmount();
+
+		/// @brief Getter, gets the active filesystem.
+		/// @return
+		static IFilesystemMgr* GetMounted();
+
+	public:
+		virtual NodePtr Create(_Input const Char* path)			 = 0;
+		virtual NodePtr CreateAlias(_Input const Char* path)	 = 0;
+		virtual NodePtr CreateDirectory(_Input const Char* path) = 0;
+		virtual NodePtr CreateSwapFile(const Char* path)		 = 0;
+
+	public:
+		virtual bool Remove(_Input const Char* path) = 0;
+
+	public:
+		virtual NodePtr Open(_Input const Char* path, _Input const Char* r) = 0;
+
+	public:
+		virtual Void Write(_Input NodePtr node, _Input VoidPtr data, _Input Int32 flags, _Input SizeT size) = 0;
+
+		virtual _Output VoidPtr Read(_Input NodePtr node,
+									 _Input Int32	flags,
+									 _Input SizeT	sz) = 0;
+
+		virtual Void Write(_Input const Char* name,
+						   _Input NodePtr	  node,
+						   _Input VoidPtr	  data,
+						   _Input Int32		  flags,
+						   _Input SizeT		  size) = 0;
+
+		virtual _Output VoidPtr Read(_Input const Char* name,
+									 _Input NodePtr		node,
+									 _Input Int32		flags,
+									 _Input SizeT		sz) = 0;
+
+	public:
+		virtual bool Seek(_Input NodePtr node, _Input SizeT off) = 0;
+
+	public:
+		virtual SizeT Tell(_Input NodePtr node)	  = 0;
+		virtual bool  Rewind(_Input NodePtr node) = 0;
+	};
+
+#ifdef __FSKIT_INCLUDES_NEFS__
+	/**
+	 * @brief Based of IFilesystemMgr, takes care of managing NeFS
+	 * disks.
+	 */
+	class NeFileSystemMgr final : public IFilesystemMgr
+	{
+	public:
+		explicit NeFileSystemMgr();
+		~NeFileSystemMgr() override;
+
+	public:
+		ZKA_COPY_DEFAULT(NeFileSystemMgr);
+
+	public:
+		NodePtr Create(const Char* path) override;
+		NodePtr CreateAlias(const Char* path) override;
+		NodePtr CreateDirectory(const Char* path) override;
+		NodePtr CreateSwapFile(const Char* path) override;
+
+	public:
+		bool	Remove(_Input const Char* path) override;
+		NodePtr Open(_Input const Char* path, _Input const Char* r) override;
+		Void	Write(_Input NodePtr node, _Input VoidPtr data, _Input Int32 flags, _Input SizeT sz) override;
+		VoidPtr Read(_Input NodePtr node, _Input Int32 flags, _Input SizeT sz) override;
+		bool	Seek(_Input NodePtr node, _Input SizeT off) override;
+		SizeT	Tell(_Input NodePtr node) override;
+		bool	Rewind(_Input NodePtr node) override;
+
+		Void Write(_Input const Char* name,
+				   _Input NodePtr	  node,
+				   _Input VoidPtr	  data,
+				   _Input Int32		  flags,
+				   _Input SizeT		  size) override;
+
+		_Output VoidPtr Read(_Input const Char* name,
+							 _Input NodePtr		node,
+							 _Input Int32		flags,
+							 _Input SizeT		sz) override;
+
+	public:
+		/// @brief Get NeFS parser class.
+		/// @return The filesystem parser class.
+		NeFileSystemParser* GetParser() noexcept;
+
+	private:
+		NeFileSystemParser* mParser{nullptr};
+	};
+
+#endif // ifdef __FSKIT_INCLUDES_NEFS__
+
+	/**
+	 * FileStream class.
+	 * @tparam Encoding file encoding (char, wchar_t...)
+	 * @tparam FSClass Filesystem contract who takes care of it.
+	 */
+	template <typename Encoding = Char,
+			  typename FSClass	= IFilesystemMgr>
+	class FileStream final
+	{
+	public:
+		explicit FileStream(const Encoding* path, const Encoding* restrict_type);
+		~FileStream();
+
+	public:
+		FileStream& operator=(const FileStream&);
+		FileStream(const FileStream&);
+
+	public:
+		ErrorOr<Int64> Write(const SizeT offset, const VoidPtr data, SizeT len) noexcept
+		{
+			if (this->fFileRestrict != kFileMgrRestrictReadWrite &&
+				this->fFileRestrict != kFileMgrRestrictReadWriteBinary &&
+				this->fFileRestrict != kFileMgrRestrictWrite &&
+				this->fFileRestrict != kFileMgrRestrictWriteBinary)
+				return ErrorOr<Int64>(kErrorInvalidData);
+
+			if (data == nullptr)
+				return ErrorOr<Int64>(kErrorInvalidData);
+
+			auto man = FSClass::GetMounted();
+
+			if (man)
+			{
+				man->Write(offset, fFile, data, len);
+				return ErrorOr<Int64>(0);
+			}
+
+			return ErrorOr<Int64>(kErrorInvalidData);
+		}
+
+		ErrorOr<Int64> Write(const Char* name, const VoidPtr data, SizeT len) noexcept
+		{
+			if (this->fFileRestrict != kFileMgrRestrictReadWrite &&
+				this->fFileRestrict != kFileMgrRestrictReadWriteBinary &&
+				this->fFileRestrict != kFileMgrRestrictWrite &&
+				this->fFileRestrict != kFileMgrRestrictWriteBinary)
+				return ErrorOr<Int64>(kErrorInvalidData);
+
+			if (data == nullptr)
+				return ErrorOr<Int64>(kErrorInvalidData);
+
+			auto man = FSClass::GetMounted();
+
+			if (man)
+			{
+				man->Write(name, fFile, data, 0, len);
+				return ErrorOr<Int64>(0);
+			}
+
+			return ErrorOr<Int64>(kErrorInvalidData);
+		}
+
+		VoidPtr Read(const Char* name, const SizeT sz) noexcept
+		{
+			if (this->fFileRestrict != kFileMgrRestrictReadWrite &&
+				this->fFileRestrict != kFileMgrRestrictReadWriteBinary &&
+				this->fFileRestrict != kFileMgrRestrictRead &&
+				this->fFileRestrict != kFileMgrRestrictReadBinary)
+				return nullptr;
+
+			auto man = FSClass::GetMounted();
+
+			if (man)
+			{
+				VoidPtr ret = man->Read(name, fFile, kFileReadAll, 0);
+				return ret;
+			}
+
+			return nullptr;
+		}
+
+		VoidPtr Read(SizeT offset, const SizeT sz)
+		{
+			if (this->fFileRestrict != kFileMgrRestrictReadWrite &&
+				this->fFileRestrict != kFileMgrRestrictReadWriteBinary &&
+				this->fFileRestrict != kFileMgrRestrictRead &&
+				this->fFileRestrict != kFileMgrRestrictReadBinary)
+				return nullptr;
+
+			auto man = FSClass::GetMounted();
+
+			if (man)
+			{
+				man->Seek(fFile, offset);
+				auto ret = man->Read(fFile, kFileReadChunk, sz);
+
+				return ret;
+			}
+
+			return nullptr;
+		}
+
+	public:
+		/// @brief Leak node pointer.
+		/// @return The node pointer.
+		NodePtr Leak()
+		{
+			return fFile;
+		}
+
+		/// @brief Leak MIME.
+		/// @return The MIME.
+		Char* MIME() noexcept
+		{
+			return const_cast<Char*>(fMime);
+		}
+
+		enum
+		{
+			kFileMgrRestrictRead,
+			kFileMgrRestrictReadBinary,
+			kFileMgrRestrictWrite,
+			kFileMgrRestrictWriteBinary,
+			kFileMgrRestrictReadWrite,
+			kFileMgrRestrictReadWriteBinary,
+		};
+
+	private:
+		NodePtr		fFile{nullptr};
+		Int32		fFileRestrict{kFileMgrRestrictReadBinary};
+		const Char* fMime{kFileMimeGeneric};
+	};
+
+	using FileStreamUTF8  = FileStream<Char>;
+	using FileStreamUTF16 = FileStream<WideChar>;
+
+	typedef UInt64 CursorType;
+
+	inline static const auto kRestrictStrLen = 8U;
+
+	/// @brief restrict information about the file descriptor.
+	struct FileRestrictKind final
+	{
+		Char  fRestrict[kRestrictStrLen];
+		Int32 fMappedTo;
+	};
+
+	/// @brief constructor
+	template <typename Encoding, typename Class>
+	inline FileStream<Encoding, Class>::FileStream(const Encoding* path,
+												   const Encoding* restrict_type)
+		: fFile(Class::GetMounted()->Open(path, restrict_type))
+	{
+		const SizeT			   kRestrictCount  = kRestrictMax;
+		const FileRestrictKind kRestrictList[] = {
+			{
+				.fRestrict = kRestrictR,
+				.fMappedTo = kFileMgrRestrictRead,
+			},
+			{
+				.fRestrict = kRestrictRB,
+				.fMappedTo = kFileMgrRestrictReadBinary,
+			},
+			{
+				.fRestrict = kRestrictRWB,
+				.fMappedTo = kFileMgrRestrictReadWriteBinary,
+			},
+			{
+				.fRestrict = kRestrictW,
+				.fMappedTo = kFileMgrRestrictWrite,
+			},
+			{
+				.fRestrict = kRestrictWB,
+				.fMappedTo = kFileMgrRestrictReadWrite,
+			}};
+
+		for (SizeT index = 0; index < kRestrictCount; ++index)
+		{
+			if (rt_string_cmp(restrict_type, kRestrictList[index].fRestrict,
+							  rt_string_len(kRestrictList[index].fRestrict)) == 0)
+			{
+				fFileRestrict = kRestrictList[index].fMappedTo;
+				break;
+			}
+		}
+
+		kcout << "new file: " << path << ".\r";
+	}
+
+	/// @brief destructor of the file stream.
+	template <typename Encoding, typename Class>
+	inline FileStream<Encoding, Class>::~FileStream()
+	{
+		mm_delete_heap(fFile);
+	}
+} // namespace Kernel
+
+#endif // ifndef INC_FILEMGR_H