add directory Minix

Minix/CD-ROM-2.0/DOSUTILS/FIPS/SOURCE/FAT.CPP

@@ -0,0 +1,161 @@
+/*
+	FIPS - the First nondestructive Interactive Partition Splitting program
+
+	Module fat.cpp
+
+	RCS - Header:
+	$Header: c:/daten/fips/source/main/RCS/fat.cpp 1.4 1995/01/19 00:00:51 schaefer Exp schaefer $
+
+	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
+*/
+
+#include <stdlib.h>
+
+#include "logdr_st.h"
+#include "global.h"
+#include "fat.h"
+#include "input.h"
+
+
+fat::fat (class logical_drive *logical_drive,int number)
+{
+	fat::logical_drive = logical_drive;
+	fat::number = number;
+	buffer = new sector;
+	start_sector = (number == 1) ? logical_drive->info().start_fat1 : logical_drive->info().start_fat2;
+	sector_in_buffer = -1;
+}
+
+
+dword fat16::next_cluster (dword cluster_number)
+{
+	dword sector = cluster_number / 256;
+	int offset = (cluster_number % 256) * 2;
+
+	if (sector != sector_in_buffer)
+	{
+		read_sector (sector);
+	}
+
+	return ((dword) buffer->data[offset] | ((dword) buffer->data[offset + 1] << 8));
+}
+
+
+void fat::read_sector (dword sector)
+{
+	if (logical_drive->read_sector (sector + start_sector,buffer))
+		if (number == 1)
+			error ("Error reading FAT 1");
+		else
+			error ("Error reading FAT 2");
+
+	sector_in_buffer = sector;
+}
+
+
+void fat16::check_against (class fat16 *fat2)
+{
+	printx ("Checking FAT ... ");
+
+	for (int i=0;i<logical_drive->bpb().sectors_per_fat;i++)
+	{
+		read_sector (i);
+		fat2->read_sector (i);
+
+		for (int j=0;j<512;j++) if (buffer->data[j] != fat2->buffer->data[j])
+			error ("FAT copies differ: FAT 1 -> %02Xh, FAT 2 -> %02Xh in sector %u, byte %u",buffer->data[j],fat2->buffer->data[j],i,j);
+
+		if (i == 0)
+		{
+			if (buffer->data[0] != 0xf8)
+			{
+				warning (false, "Wrong media descriptor byte in FAT: %02Xh",buffer->data[0]);
+
+				printx ("Continue (y/n)? ");
+				if (ask_yes_no () == 'n') exit (-1);
+			}
+
+			if ((buffer->data[1] != 0xff) || (buffer->data[2] != 0xff) || (buffer->data[3] != 0xff))
+				warning (true, "Wrong FAT entries 1 & 2: %02X %02X %02X %02X",buffer->data[0],buffer->data[1],buffer->data[2],buffer->data[3]);
+		}
+	}
+	printx ("OK\n");
+}
+
+
+void fat16::check_empty (dword new_start_sector)
+{
+	dword first_cluster = (new_start_sector - logical_drive->info().start_data) / logical_drive->bpb().sectors_per_cluster + 2;
+
+	dword last_cluster = logical_drive->info().no_of_clusters + 1;
+
+	if (last_cluster > ((dword) 256 * logical_drive->bpb().sectors_per_fat - 1)) last_cluster = (dword) 256 * logical_drive->bpb().sectors_per_fat - 1;
+
+	printx ("First Cluster: %lu\nLast Cluster: %lu\n\n",first_cluster,last_cluster);
+	printx ("Testing if empty ... ");
+
+	for (dword i=first_cluster;i <= last_cluster;i++)
+	{
+		dword fat_entry = next_cluster (i);
+
+		if (fat_entry != 0) if (fat_entry != 0xfff7)
+		{
+			if (fat_entry == 0xffff)
+			{
+				error ("New partition not empty: cluster %lu ( FAT entry: <EOF> )",i);
+			}
+			else
+			{
+				error ("New partition not empty: cluster %lu ( FAT entry: %lu )",i,fat_entry);
+			}
+		}
+	}
+	
+	printx ("OK\n");
+}
+
+
+dword fat16::min_free_cluster (void)
+{
+	dword first_cluster = 2;
+
+	dword last_cluster = logical_drive->info().no_of_clusters + 1;
+
+	if (last_cluster > ((dword) 256 * logical_drive->bpb().sectors_per_fat - 1)) last_cluster = (dword) 256 * logical_drive->bpb().sectors_per_fat - 1;
+
+	printx ("Searching for free space ... ");
+
+	dword i;
+
+	for (i=last_cluster;i >= first_cluster;i--)
+	{
+		dword fat_entry = next_cluster (i);
+
+		if (fat_entry != 0) if (fat_entry != 0xfff7)
+		{
+			i++;
+			break;
+		}
+	}
+	printx ("OK\n\n");
+	return (i);
+}