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engines/m4/fileio/sys_file.h

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+/* ScummVM - Graphic Adventure Engine
+ *
+ * ScummVM is the legal property of its developers, whose names
+ * are too numerous to list here. Please refer to the COPYRIGHT
+ * file distributed with this source distribution.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#ifndef M4_FILEIO_SYS_FILE_H
+#define M4_FILEIO_SYS_FILE_H
+
+#include "common/file.h"
+#include "m4/fileio/fileio.h"
+#include "m4/mem/reloc.h"
+
+namespace M4 {
+
+struct Hash_Record {
+	Common::String filename;
+	byte hagfile;
+	byte disks;
+	uint32 offset;
+	uint32 size;
+};
+
+struct Hag_Statics {
+	bool hag_flag = false;
+	bool first_read_flag = false;
+	Common::Path hash_file;
+	Hag_Name_Record *hag_name_list = nullptr;
+	Hag_Record *hag_file_list = nullptr;
+};
+
+class SysFile {
+private:
+	Common::Stream *_fp = nullptr;
+	FileMode fmode;
+	AccessMode mode = UNOPENED;
+	int hag_success = 0;
+	bool show_error_flag = true;
+	Hag_Record *curr_hag_record = nullptr;
+	Hash_Record curr_hash_record;
+	uint32 last_head_pos = 0;
+
+private:
+	void open_read();
+	void open_write();
+	void open_read_low_level();
+	bool open_hash_file();
+	Common::String get_last_string(const Common::String &src);
+
+	/**
+	 * Calculate key (which is string) into hash table address ie. hash table entry
+	 */
+	uint32 key_to_hash_address(const Common::String &src, uint32 hash_table_size);
+
+	/**
+	 * Insert a hash record into HASH file depending hash_address. The algorithm is
+	 * if hash_address entry is empty record, put the new record into this entry,
+	 * if the hash_address entry is not empty, search next record of it, util find
+	 * one empty entry and put the new record into the empty entry.
+	*/
+	int hash_search(const Common::String &fname, Hash_Record *current_hash_record_ptr, Hag_Record *curr_hag_record, uint32 hash_address,
+		Common::SeekableReadStream *hashfp, uint32 hash_table_size, bool show_error_flag);
+
+	/**
+	 * Opens the file for access, paying attention to the first character..
+	 * if it's a '*', it indicates a MADS folder file
+	 */
+	Common::Stream *open_by_first_char();
+
+	bool get_local_name_from_hagfile(Common::String &local_name, byte hagfile);
+
+	Common::SeekableReadStream *rs() const;
+
+public:
+	Common::String filename;
+
+public:
+	SysFile(const Common::String &fname, FileMode myfmode = BINARY);
+
+	/**
+	 * Return true if the file exists
+	 */
+	bool exists();
+
+	/**
+	 * Returns the file size
+	 */
+	uint32 size();
+
+	/**
+	 * Gets the current position
+	 */
+	uint32 get_pos();
+
+	/**
+	 * Seek to a given position
+	 */
+	bool seek(uint32 pos);
+
+	/**
+	 * Seek ahead by a given amount
+	 */
+	bool seek_ahead(int32 amount);
+
+	/**
+	 * Read data
+	 */
+	uint32 read(MemHandle bufferHandle);
+	int32 read(MemHandle bufferHandle, int32 n);
+	int32 read(byte *bufferHandle, int32 n);
+
+	/**
+	 * Read in a 8-bit value
+	 */
+	byte readByte();
+	int8 readSByte() {
+		return (int8)readByte();
+	}
+
+	/**
+	 * Read in a 16-bit value
+	 */
+	uint16 readUint16LE();
+	int16 readSint16LE() {
+		return (int16)readUint16LE();
+	}
+
+	/**
+	 * Read in a 32-bit value
+	 */
+	uint32 readUint32LE();
+	int32 readSint32LE() {
+		return (int32)readUint32LE();
+	}
+
+	/**
+	 * Close the file
+	 */
+	void close();
+};
+
+void sysfile_init(bool in_hag_mode);
+void sysfile_shutdown();
+
+} // namespace M4
+
+#endif