65 lines
1.6 KiB
C
65 lines
1.6 KiB
C
/*
|
|
* DOS interrupt 25h handler
|
|
*/
|
|
|
|
#include <stdlib.h>
|
|
#include <string.h>
|
|
#include <fcntl.h>
|
|
#include <unistd.h>
|
|
#include "msdos.h"
|
|
#include "ldt.h"
|
|
#include "miscemu.h"
|
|
#include "drive.h"
|
|
#include "debug.h"
|
|
|
|
/**********************************************************************
|
|
* INT_Int25Handler
|
|
*
|
|
* Handler for int 25h (absolute disk read).
|
|
*/
|
|
void WINAPI INT_Int25Handler( CONTEXT *context )
|
|
{
|
|
BYTE *dataptr = CTX_SEG_OFF_TO_LIN( context, DS_reg(context), BX_reg(context) );
|
|
DWORD begin, length;
|
|
int fd;
|
|
|
|
if (!DRIVE_IsValid(AL_reg(context)))
|
|
{
|
|
SET_CFLAG(context);
|
|
AX_reg(context) = 0x0101; /* unknown unit */
|
|
return;
|
|
}
|
|
|
|
if (CX_reg(context) == 0xffff)
|
|
{
|
|
begin = *(DWORD *)dataptr;
|
|
length = *(WORD *)(dataptr + 4);
|
|
dataptr = (BYTE *)CTX_SEG_OFF_TO_LIN( context,
|
|
*(WORD *)(dataptr + 8), *(WORD *)(dataptr + 6) );
|
|
}
|
|
else
|
|
{
|
|
begin = DX_reg(context);
|
|
length = CX_reg(context);
|
|
}
|
|
TRACE(int, "int25: abs diskread, drive %d, sector %ld, "
|
|
"count %ld, buffer %d\n",
|
|
AL_reg(context), begin, length, (int) dataptr);
|
|
|
|
if ((fd = DRIVE_OpenDevice( AL_reg(context), O_RDONLY )) != -1)
|
|
{
|
|
lseek( fd, begin * 512, SEEK_SET );
|
|
/* FIXME: check errors */
|
|
read( fd, dataptr, length * 512 );
|
|
close( fd );
|
|
}
|
|
else
|
|
{
|
|
memset(dataptr, 0, length * 512);
|
|
if (begin == 0 && length > 1) *(dataptr + 512) = 0xf8;
|
|
if (begin == 1) *dataptr = 0xf8;
|
|
}
|
|
RESET_CFLAG(context);
|
|
}
|
|
|