rom/hyperlayers/locklayer.c

   1 /*
   2     Copyright © 1995-2001, The AROS Development Team. All rights reserved.
   3     $Id$
   4
   5     Desc:
   6     Lang: english
   7 */
   8 #include <aros/libcall.h>
   9 #include <proto/exec.h>
  10
  11 #define DEBUG 0
  12 #include <aros/debug.h>
  13 #undef kprintf
  14
  15 /*****************************************************************************
  16
  17     NAME */
  18 #include <proto/layers.h>
  19 #include "layers_intern.h"
  20
  21         AROS_LH2(void, LockLayer,
  22
  23 /*  SYNOPSIS */
  24         AROS_LHA(LONG          , dummy, A0),
  25         AROS_LHA(struct Layer *, layer, A1),
  26
  27 /*  LOCATION */
  28         struct LayersBase *, LayersBase, 16, Layers)
  29
  30 /*  FUNCTION
  31         Locks a layer for exclusive access by this task.
  32         A layer can be locked multiple times but has to be unlocked
  33         as many times as it has been locked so that other tasks
  34         can access it.
  35
  36     INPUTS
  37         layer - pointer to layer to be locked
  38
  39     RESULT
  40
  41     NOTES
  42
  43     EXAMPLE
  44
  45     BUGS
  46
  47     SEE ALSO
  48
  49     INTERNALS
  50
  51     HISTORY
  52         27-11-96    digulla automatically created from
  53                             layers_lib.fd and clib/layers_protos.h
  54
  55 *****************************************************************************/
  56 {
  57     AROS_LIBFUNC_INIT
  58     AROS_LIBBASE_EXT_DECL(struct LayersBase *,LayersBase)
  59
  60     D(bug("LockLayer(layer @ $%lx)\n", layer));
  61
  62     ObtainSemaphore(&layer->Lock);
  63
  64     AROS_LIBFUNC_EXIT
  65 } /* LockLayer */