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#include "stdio.h" /* ;AN000; */
#include "stdlib.h" /* ;AN000; */
#include "string.h" /* ;AN000; */
#include "dos.h" /* ;AN000; */
#include "get_stat.h" /* ;AN000; */
#include "extern.h" /* ;AN000; */
/* ;AN000; */
char read_boot_record(unsigned,unsigned char,unsigned char,unsigned char); /* ;AN000; */
void DiskIo(union REGS *,union REGS *, struct SREGS *); /* ;AN000; */
unsigned cylinders_to_mbytes(unsigned,unsigned char,unsigned char); /* ;AN000; */
char get_drive_parameters(unsigned char); /* ;AN000; */
char get_disk_info(void); /* ;AN000; */
/* ;AN000; */
/* */ /* ;AN000; */
char get_disk_info() /* ;AN000; */
/* ;AN000; */
BEGIN /* ;AN000; */
/* ;AN000; */
unsigned char i; /* ;AN000; */
/* ;AN000; */
/* Initialize values */ /* ;AN000; */
number_of_drives = uc(0); /* ;AN000; */
for (i=uc(0); i < uc(2); i++) /* ;AN000; */
BEGIN /* ;AN000; */
total_disk[i] = u(0); /* ;AN000; */
total_mbytes[i] = f(0); /* ;AN000; */
max_sector[i] = uc(0); /* ;AN000; */
max_head[0] = uc(0); /* ;AN000; */
END /* ;AN000; */
/* ;AN000; */
/* See how many drives there are */ /* ;AN000; */
if (get_drive_parameters(uc(0x80))) /* ;AN000; */
/* ;AN000; */
BEGIN /* ;AN000; */
/* Get the drive parameters for all drives */ /* ;AN000; */
for (i = uc(0); i < number_of_drives;i++) /* ;AN000; */
/* ;AN000; */
BEGIN /* ;AN000; */
if (get_drive_parameters(uc(0x80)+i)) /* ;AN000; */
/* ;AN000; */
BEGIN /* ;AN000; */
/* Save drive parameters */ /* ;AN000; */
max_sector[i] = ((unsigned char)(regs.h.cl & 0x3F)); /* ;AN000; */
max_head[i] = ((unsigned char)(regs.h.dh +1)); /* ;AN000; */
total_disk[i] = ((((unsigned)(regs.h.cl & 0xC0 )) & 0x00C0) << 2)+ ((unsigned)regs.h.ch) +1; /* ;AN000; */
total_mbytes[i] = cylinders_to_mbytes(total_disk[i], max_sector[i], max_head[i]); /* ;AN000; */
END /* ;AN000; */
else /* ;AN000; */
BEGIN /* ;AN000; */
good_disk[i] = FALSE; /* ;AN000; */
return(FALSE); /* ;AN000; */
END /* ;AN000; */
END /* ;AN000; */
return(TRUE); /* ;AN000; */
END /* ;AN000; */
else /* ;AN000; */
/* No drives present */ /* ;AN000; */
BEGIN /* ;AN000; */
no_fatal_error = FALSE; /* ;AN000; */
return(FALSE); /* ;AN000; */
END /* ;AN000; */
END /* ;AN000; */
/* ;AN000; */
/* ;AN000; */
/* ;AN000; */
/* ;AN000; */
/* */ /* ;AN000; */
char get_drive_parameters(drive) /* ;AN000; */
/* ;AN000; */
unsigned char drive; /* ;AN000; */
/* ;AN000; */
BEGIN /* ;AN000; */
/* See how many drives there are */ /* ;AN000; */
regs.h.ah = uc(DISK_INFO); /* ;AN000; */
regs.h.dl = drive; /* ;AN000; */
DiskIo(®s,®s,&segregs); /* ;AN000; */
/* ;AN000; */
/* See if any drives exist */ /* ;AN000; */
if ((regs.h.dl == uc(0)) || ((regs.x.cflag & 1) == u(1))) /* ;AN000; */
BEGIN /* ;AN000; */
return(FALSE); /* ;AN000; */
END /* ;AN000; */
else /* ;AN000; */
BEGIN /* ;AN000; */
/* Save the number of drives */ /* ;AN000; */
number_of_drives = regs.h.dl; /* ;AN000; */
if (number_of_drives < 2) good_disk[1] = FALSE; /* ;AN000; */
if (number_of_drives < 1) good_disk[0] = FALSE; /* ;AN000; */
return(TRUE); /* ;AN000; */
END /* ;AN000; */
/* ;AN000; */
END /* ;AN000; */
/* ;AN000; */
/* */ /* ;AN000; */
char read_boot_record(cylinder,which_disk,which_head,which_sector) /* ;AN000; */
/* ;AN000; */
unsigned cylinder; /* ;AN000; */
unsigned char which_disk; /* ;AN000; */
unsigned char which_head; /* ;AN000; */
unsigned char which_sector; /* ;AN000; */
/* ;AN000; */
BEGIN /* ;AN000; */
/* ;AN000; */
char far *buffer_pointer = boot_record; /* ;AN000; */
/* ;AN000; */
/* Setup read, always on a cylinder boundary */ /* ;AN000; */
regs.h.ah = uc(READ_DISK); /* ;AN000; */
regs.h.al = uc(1); /* ;AN000; */
regs.h.dh = which_head; /* ;AN000; */
regs.h.cl = which_sector; /* ;AN000; */
/* ;AN000; */
/* Specify the disk */ /* ;AN000; */
regs.h.dl = which_disk + 0x80; /* ;AN000; */
/* ;AN000; */
/* Need to scramble CX so that sectors and cyl's are in INT 13 format */ /* ;AN000; */
/* ;AN000; */
if (cylinder > u(255)) /* ;AN000; */
BEGIN /* ;AN000; */
regs.h.cl = regs.h.cl | ((char)((cylinder /256) << 6)); /* ;AN000; */
END /* ;AN000; */
regs.h.ch = (unsigned char)(cylinder & 0xFF); /* ;AN000; */
/* ;AN000; */
/* Point at the place to write the boot record */ /* ;AN000; */
regs.x.bx = FP_OFF(buffer_pointer); /* ;AN000; */
segregs.es = FP_SEG(buffer_pointer); /* ;AN000; */
/* ;AN000; */
/* read in the boot record */ /* ;AN000; */
DiskIo(®s,®s,&segregs); /* ;AN000; */
/* Check for error reading it */ /* ;AN000; */
if ((regs.x.cflag & 1) != u(1)) /* ;AN000; */
BEGIN /* ;AN000; */
return(TRUE); /* ;AN000; */
END /* ;AN000; */
else /* ;AN000; */
BEGIN /* ;AN000; */
/* Tell user there was an error */ /* ;AN000; */
good_disk[which_disk] = FALSE; /* ;AN000; */
return(FALSE); /* ;AN000; */
END /* ;AN000; */
END /* ;AN000; */
/* ;AN000; */
/* */ /* ;AN000; */
void DiskIo(InRegs,OutRegs,SegRegs) /* ;AN000; */
union REGS *InRegs; /* ;AN000; */
union REGS *OutRegs; /* ;AN000; */
struct SREGS *SegRegs; /* ;AN000; */
/* ;AN000; */
BEGIN /* ;AN000; */
/* ;AN000; */
char *WritePtr; /* ;AN000; */
/* ;AN000; */
#ifdef DEBUG /* ;AN000; */
/* ;AN000; */
switch(InRegs->h.ah) /* ;AN000; */
{ /* ;AN000; */
case 0: /* ;AN000; */
case 1: /* ;AN000; */
case 2: /* ;AN000; */
case 4: /* ;AN000; */
case 8: /* ;AN000; */
case 15: /* ;AN000; */
case 16: /* ;AN000; */
int86x((int)DISK,InRegs,OutRegs,SegRegs); /* ;AN000; */
break; /* ;AN000; */
/* ;AN000; */
default: /* ;AN000; */
WritePtr = getenv("WRITE"); /* ;AN000; */
if (strcmpi(WritePtr,"ON") != 0) /* ;AN000; */
BEGIN /* ;AN000; */
printf("\nDisallowing Disk I/O Request\n"); /* ;AN000; */
printf("AX:%04X BX:%04X CX:%04X DX:%04X ES:%04X\n", /* ;AN000; */
InRegs->x.ax,InRegs->x.bx,InRegs->x.cx,InRegs->x.dx,SegRegs->es); /* ;AN000; */
/* ;AN000; */
OutRegs->h.ah = (unsigned char) 0; /* ;AN000; */
OutRegs->x.cflag = (unsigned) 0; /* ;AN000; */
END /* ;AN000; */
else int86x((int)DISK,InRegs,OutRegs,SegRegs); /* ;AN000; */
/* ;AN000; */
break; /* ;AN000; */
/* ;AN000; */
} /* ;AN000; */
/* ;AN000; */
#else /* ;AN000; */
/* ;AN000; */
int86x((int)DISK,InRegs,OutRegs,SegRegs); /* ;AN000; */
/* ;AN000; */
#endif /* ;AN000; */
/* ;AN000; */
return; /* ;AN000; */
/* ;AN000; */
END /* ;AN000; */
/* ;AN000; */
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