Sweden-Number/msdos/int25.c

55 lines
1.3 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"
DEFAULT_DEBUG_CHANNEL(int)
/**********************************************************************
* 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), EBX_reg(context) );
DWORD begin, length;
if (!DRIVE_IsValid(AL_reg(context)))
{
SET_CFLAG(context);
AX_reg(context) = 0x0201; /* 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), *(DWORD *)(dataptr + 6) );
}
else
{
begin = DX_reg(context);
length = CX_reg(context);
}
TRACE(int, "int25: abs diskread, drive %d, sector %ld, "
"count %ld, buffer %p\n",
AL_reg(context), begin, length, dataptr);
DRIVE_RawRead(AL_reg(context), begin, length, dataptr, TRUE);
RESET_CFLAG(context);
}