msdos/int25.c

   1 /*
   2  * DOS interrupt 25h handler
   3  *
   4  * Copyright 1997 Andreas Mohr
   5  *
   6  * This library is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2.1 of the License, or (at your option) any later version.
  10  *
  11  * This library is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with this library; if not, write to the Free Software
  18  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  19  */
  20
  21 #include <stdlib.h>
  22 #include <string.h>
  23 #include <fcntl.h>
  24 #include <unistd.h>
  25 #include "msdos.h"
  26 #include "miscemu.h"
  27 #include "drive.h"
  28 #include "wine/debug.h"
  29
  30 WINE_DEFAULT_DEBUG_CHANNEL(int);
  31
  32
  33 /**********************************************************************
  34  *          INT_Int25Handler (WPROCS.137)
  35  *
  36  * Handler for int 25h (absolute disk read).
  37  */
  38 void WINAPI INT_Int25Handler( CONTEXT86 *context )
  39 {
  40     BYTE *dataptr = CTX_SEG_OFF_TO_LIN( context, context->SegDs, context->Ebx );
  41     DWORD begin, length;
  42
  43     if (!DRIVE_IsValid(LOBYTE(context->Eax)))
  44     {
  45         SET_CFLAG(context);
  46         AX_reg(context) = 0x0201;        /* unknown unit */
  47         return;
  48     }
  49
  50     if (LOWORD(context->Ecx) == 0xffff)
  51     {
  52         begin   = *(DWORD *)dataptr;
  53         length  = *(WORD *)(dataptr + 4);
  54         dataptr = (BYTE *)CTX_SEG_OFF_TO_LIN( context,
  55                                         *(WORD *)(dataptr + 8), *(DWORD *)(dataptr + 6) );
  56     }
  57     else
  58     {
  59         begin  = LOWORD(context->Edx);
  60         length = LOWORD(context->Ecx);
  61     }
  62     TRACE("int25: abs diskread, drive %d, sector %ld, "
  63                  "count %ld, buffer %p\n",
  64           LOBYTE(context->Eax), begin, length, dataptr);
  65
  66     DRIVE_RawRead(LOBYTE(context->Eax), begin, length, dataptr, TRUE);
  67     RESET_CFLAG(context);
  68 }
  69