new file mode 100644
--- /dev/null
+++ b/system/file_impl.h
@@ -0,0 +1,157 @@
+/*
+ * Copyright (c) 2004  Kazunori "jagarl" Ueno
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+
+
+#ifndef __FILE_IMPL_H__
+#define __FILE_IMPL_H__
+
+#include<vector>
+
+struct ARCFILE_ATOM {
+	char* filename;
+	char* filename_lower;
+	off_t offset;
+	int arcsize;
+	int filesize;
+	int private_data;
+	bool operator <(const ARCFILE_ATOM& to) const {
+		return strcmp(filename_lower, to.filename_lower) < 0;
+	}
+	bool operator <(char* const to) const {
+		return strcmp(filename_lower, to) < 0;
+	}
+};
+
+class ARCFILE {
+protected:
+	char* arcname;
+	char* filenames_orig;
+	int list_point;
+	std::vector<ARCFILE_ATOM> arc_atom;
+	typedef std::vector<ARCFILE_ATOM>::iterator iterator;
+	ARCFILE* next; /* FILESEARCH の一つの型が複数の ARCFILE を持つとき、リストをつくる */
+	/* arcname に指定されたファイル／ディレクトリの内容チェック */
+	virtual int CheckFileDeal(void);
+	virtual void ListupFiles(int fname_len);
+	virtual ARCINFO* MakeARCINFO(ARCFILE_ATOM&);
+	iterator SearchName(const char* f, const char* ext=0);
+public:
+	ARCFILE(char* fname);
+	void SetNext(ARCFILE* _next) { next = _next;}
+	ARCFILE* Next(void) { return next; }
+	void Init(void);
+	virtual ~ARCFILE();
+	/* ファイル検索 */
+	class ARCINFO* Find(const char* fname, const char* ext);
+	/* ファイルリストの出力 */
+	int Deal(void) { Init(); return arc_atom.size(); }
+	void ListFiles(FILE* out);
+	void InitList(void);
+	char* ListItem(void);
+};
+
+class SCN2kFILE : public ARCFILE {
+protected:
+	virtual int CheckFileDeal(void);
+	virtual void ListupFiles(int fname_len);
+	virtual ARCINFO* MakeARCINFO(ARCFILE_ATOM& atom);
+public:
+	SCN2kFILE(char* fname) : ARCFILE(fname) {}
+	virtual ~SCN2kFILE() {}
+};
+
+class CattleyaFILE : public ARCFILE {
+	bool is_compress;
+	/* header の Huffman 木構築用 */
+	char* bitbuf;
+	char* bitbuf_end;
+	int ltree[0x400];
+	int rtree[0x400];
+	int treecnt;
+	int bitcnt;
+	int GetBit(void);
+	int GetCh(void);
+	void SetBuf(char* buf, int len);
+	int MakeTree(void);
+	int Decode(int seed);
+
+protected:
+	virtual int CheckFileDeal(void);
+	virtual void ListupFiles(int fname_len);
+	virtual ARCINFO* MakeARCINFO(ARCFILE_ATOM& atom);
+public:
+	CattleyaFILE(char* fname) : ARCFILE(fname) {is_compress = false;}
+	virtual ~CattleyaFILE() {}
+};
+
+class NULFILE : public ARCFILE {
+protected:
+	virtual int CheckFileDeal(void);
+	virtual void ListupFiles(int fname_len);
+	virtual ARCINFO* MakeARCINFO(ARCFILE_ATOM& atom);
+public:
+	NULFILE() : ARCFILE("") {}
+	virtual ~NULFILE() {}
+};
+class DIRFILE : public ARCFILE {
+protected:
+	virtual int CheckFileDeal(void);
+	virtual void ListupFiles(int fname_len);
+	virtual ARCINFO* MakeARCINFO(ARCFILE_ATOM& atom);
+public:
+	DIRFILE(char* fname) : ARCFILE(fname) {}
+	virtual ~DIRFILE() {}
+	FILE* Open(const char* fname); /* FILE* を開く */
+	char* SearchFile(const char* dirname); /* ファイル検索 */
+};
+class ARCINFO_AVG32 : public ARCINFO {
+	ARCINFO_AVG32(const char* name, ARCFILE_ATOM& atom) : ARCINFO(name, atom) {
+	}
+	virtual bool ExecExtract(void);
+	friend class ARCFILE;
+};
+class ARCINFO2k : public ARCINFO {
+	static char decode_seed[256];
+	static char decode_seed2[16];
+protected:
+	ARCINFO2k(const char* name, ARCFILE_ATOM& atom) : ARCINFO(name,atom) {
+	}
+	virtual bool ExecExtract(void);
+	friend class SCN2kFILE;
+};
+
+class ARCINFOZ : public ARCINFO {
+protected:
+	ARCINFOZ(const char* name, ARCFILE_ATOM& atom) : ARCINFO(name, atom) {
+	}
+	virtual bool ExecExtract(void);
+	friend class DaemonBaneFILE;
+	friend class CattleyaFILE;
+};
+
+#endif /* __FILE_IMPL_H__ */