rom/exec/closedevice.c

   1 /*
   2     Copyright © 1995-2001, The AROS Development Team. All rights reserved.
   3     $Id$
   4
   5     Desc: Close a device.
   6     Lang: english
   7 */
   8 #include <aros/config.h>
   9 #include <exec/execbase.h>
  10 #include <exec/io.h>
  11 #include <exec/devices.h>
  12 #include <dos/dos.h>
  13 #include <aros/libcall.h>
  14 #include <proto/exec.h>
  15
  16 #include "exec_debug.h"
  17 #ifndef DEBUG_CloseDevice
  18 #   define DEBUG_CloseDevice 0
  19 #endif
  20 #undef DEBUG
  21 #if DEBUG_CloseDevice
  22 #   define DEBUG 1
  23 #endif
  24 #include <aros/debug.h>
  25 #undef kprintf
  26
  27 #if (AROS_FLAVOUR & AROS_FLAVOUR_NATIVE)
  28 #   define NATIVE(x)        x
  29 #else
  30 #   define NATIVE(x)        /* eps */
  31 #endif
  32
  33 /*****************************************************************************
  34
  35     NAME */
  36
  37         AROS_LH1(void, CloseDevice,
  38
  39 /*  SYNOPSIS */
  40         AROS_LHA(struct IORequest *, iORequest, A1),
  41
  42 /*  LOCATION */
  43         struct ExecBase *, SysBase, 75, Exec)
  44
  45 /*  FUNCTION
  46         Closes a previously opened device. Any outstanding I/O requests must
  47         be finished. It is safe to call CloseDevice with a cleared iorequest
  48         structure or one that failed to open.
  49
  50     INPUTS
  51         iORequest - Pointer to iorequest structure.
  52
  53     RESULT
  54
  55     NOTES
  56
  57     EXAMPLE
  58
  59     BUGS
  60
  61     SEE ALSO
  62         OpenDevice().
  63
  64     INTERNALS
  65
  66 ******************************************************************************/
  67 {
  68     AROS_LIBFUNC_INIT
  69     NATIVE(BPTR dc_ret;)
  70
  71     D(bug("CloseDevice $%lx $%lx (\"%s\") by \"%s\"\n", iORequest, iORequest->io_Device,
  72         iORequest->io_Device ? iORequest->io_Device->dd_Library.lib_Node.ln_Name : "(null)",
  73         SysBase->ThisTask->tc_Node.ln_Name));
  74
  75     /* Single-thread the close routine. */
  76     Forbid();
  77
  78     /* Something to do? */
  79     if(iORequest->io_Device!=NULL)
  80     {
  81         NATIVE(dc_ret =) AROS_LVO_CALL1(BPTR,
  82             AROS_LCA(struct IORequest *,iORequest, A1),
  83             struct Device *,iORequest->io_Device,2,
  84         );
  85         /*
  86             Normally you'd expect the device to be expunged if this returns
  87             non-zero, but this is only exec which doesn't know anything about
  88             seglists - therefore dos.library has to SetFunction() into this
  89             vector for the additional functionality.
  90         */
  91
  92         /* Trash device field */
  93         iORequest->io_Device=(struct Device *)-1;
  94     }
  95 #if (AROS_FLAVOUR & AROS_FLAVOUR_NATIVE)
  96     else
  97     {
  98         /* local vars not guaranteed to be initialised to 0 */
  99         dc_ret = 0;
 100     }
 101 #endif
 102
 103     /* All done. */
 104     Permit();
 105
 106 #if (AROS_FLAVOUR & AROS_FLAVOUR_NATIVE)
 107     /*
 108         Kludge to force the seglist to register d0. Ramlib patches this
 109         vector for seglist expunge capability and expects the seglist in
 110         d0 after it has called the original (this) function.
 111         Also see CloseLibrary().
 112     */
 113     {
 114         /* Put the library base in register d0 */
 115         register BPTR ret __asm("d0") = dc_ret;
 116
 117         /* Make sure the above assignment isn't optimized away */
 118         asm volatile("": : "r" (ret));
 119     }
 120 #endif
 121
 122     AROS_LIBFUNC_EXIT
 123 } /* CloseDevice */
 124