www.pudn.com > minix.instalation.cd-rom-2.0.rar > LOGDR_ST.H

/*  
	FIPS - the First nondestructive Interactive Partition Splitting program  
  
	Module logdr_st.h  
  
	RCS - Header:  
	$Header: c:/daten/fips/source/main/RCS/logdr_st.h 1.4 1995/01/19 00:01:27 schaefer Exp $  
  
	Copyright (C) 1993 Arno Schaefer  
  
	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 2 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, write to the Free Software  
	Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.  
  
  
	Report problems and direct all questions to:  
  
	schaefer@rbg.informatik.th-darmstadt.de  
*/  
  
#ifndef LOGDR_ST_H  
#define LOGDR_ST_H  
  
#include "types.h"  
#include "disk_io.h"  
  
  
/* ----------------------------------------------------------------------- */  
/* Class boot_sector - derived from structure sector                       */  
/* Must be initialized with pointer to logical drive object                */  
/* Read() and write() read/write sector 0 of logical drive                 */  
/* ----------------------------------------------------------------------- */  
  
class boot_sector:public sector  
{  
	class logical_drive *logical_drive;  
public:  
// constructor  
  
	boot_sector (class logical_drive *logical_drive)  
	{ boot_sector::logical_drive = logical_drive; }  
  
  
// functions  
  
	int read (void);  
	int write (void);  
};  
  
  
/* ------------------------------------------------------------------------ */  
/* Bios Parameter Block structure                                           */  
/* This is not exactly the BPB as understood by DOS, because it contains    */  
/* the additional fields that are in the boot_sector like jump_instruction, */  
/* oem_name etc. Get() extracts info from the boot_sector, put() writes the */  
/* info back into the boot_sector buffer.                                   */  
/* ------------------------------------------------------------------------ */  
  
struct bios_parameter_block  
{  
	byte jump_instruction[3];	// EB xx 90 or E9 xx xx  
	char oem_name[9];  
	word bytes_per_sector;          // usually 512  
	byte sectors_per_cluster;       // may differ  
	word reserved_sectors;          // usually 1 (boot_sector)  
	byte no_of_fats;                // usually 2  
	word no_of_rootdir_entries;     // usually 512 for HDs (?), 224 for  
					// HD-Floppies, 112 for DD-Floppies  
	word no_of_sectors;             // 0 on BIGDOS partitions  
	byte media_descriptor;          // usually F8h  
	word sectors_per_fat;           // depends on partition size  
	word sectors_per_track;         // depends on drive  
	word drive_heads;               // dto.  
	dword hidden_sectors;           // first sector of partition or 0 for FDs  
	dword no_of_sectors_long;       // number of sectors on BIGDOS partitions  
	byte phys_drive_no;             // usually 80h  
	byte signature;                 // usually 29h  
	dword serial_number;            // random  
	char volume_label[12];  
	char file_system_id[9];  
  
	void get (boot_sector *boot_sector);  
	void put (boot_sector *boot_sector);  
};  
  
  
/* ----------------------------------------------------------------------- */  
/* Some miscellaneous figures about the drive                              */  
/* Get() extracts this info from the BPB                                   */  
/* ----------------------------------------------------------------------- */  
  
struct logical_drive_info  
{  
	dword start_fat1;  
	dword start_fat2;  
	dword start_rootdir;  
	dword start_data;  
	dword no_of_clusters;  
  
	virtual void get (const bios_parameter_block &bpb);  
};  
  
  
/* ----------------------------------------------------------------------- */  
/* Abstract Class logical_drive. This can be any DOS drive that allows     */  
/* direct reading and writing of sectors, like Harddisk Partitions, Floppy */  
/* disks or Ramdisks                                                       */  
/* ----------------------------------------------------------------------- */  
  
class logical_drive  
{  
// private data  
  
	struct bios_parameter_block pr_bpb;  
	struct logical_drive_info pr_info;  
  
public:  
  
// public data  
  
	class boot_sector *boot_sector;  
  
// member access functions  
  
	virtual bios_parameter_block &bpb() { return pr_bpb; }  
	virtual logical_drive_info &info() { return pr_info; }  
  
// functions  
  
	virtual int read_sector (dword number,sector *sector) = 0;  
	virtual int write_sector (dword number,sector *sector) = 0;  
	// pure virtual functions  
  
	int read_boot_sector (void) { return (boot_sector->read ()); }  
	int write_boot_sector (void) { return (boot_sector->write ()); }  
  
	void get_bpb (void) { bpb().get (boot_sector); }  
	void put_bpb (void) { bpb().put (boot_sector); }  
  
	void get_info (void) { info().get (bpb ()); }  
};  
  
  
/* ----------------------------------------------------------------------- */  
/* Function to read boot_sector from logical drive                         */  
/* It must be in the header file because it is inline                      */  
/* ----------------------------------------------------------------------- */  
  
inline int boot_sector::read (void)  
{  
	return logical_drive->read_sector (0,this);  
}  
  
  
/* ----------------------------------------------------------------------- */  
/* Function to write boot_sector to logical drive                          */  
/* ----------------------------------------------------------------------- */  
  
inline int boot_sector::write (void)  
{  
	return logical_drive->write_sector (0,this);  
}  
  
#endif