rom/graphics/attemptlocklayerrom.c

   1 /*
   2     Copyright © 1995-2007, The AROS Development Team. All rights reserved.
   3     $Id$
   4
   5     Desc: Graphics function AttemptLockLayerRom()
   6     Lang: english
   7 */
   8 #include <proto/layers.h>
   9 #include <graphics/clip.h>
  10 #include <proto/exec.h>
  11 #include <exec/types.h>
  12
  13 /*****************************************************************************
  14
  15     NAME */
  16 #include <proto/graphics.h>
  17
  18         AROS_LH1(BOOL, AttemptLockLayerRom,
  19
  20 /*  SYNOPSIS */
  21         AROS_LHA(struct Layer *, l, A5),
  22
  23 /*  LOCATION */
  24         struct GfxBase *, GfxBase, 109, Graphics)
  25
  26 /*  FUNCTION
  27         Try to lock the current layer. If it is already locked this
  28         function will return FALSE, TRUE otherwise.
  29         If the layer could be locked successfully nesting will take place
  30         which means that for every successful locking of a layer
  31         UnlockLayerRom() has to be called for that layer to let other
  32         tasks access that layer.
  33
  34     INPUTS
  35         l - pointer to layer
  36
  37     RESULT
  38         TRUE  - layer is successfully locked for the task
  39         FALSE - layer could not be locked, it's locked by another task.
  40
  41     NOTES
  42
  43     EXAMPLE
  44
  45     BUGS
  46
  47     SEE ALSO
  48       LockLayerRom(), UnlockLayerRom()
  49
  50     INTERNALS
  51
  52     HISTORY
  53
  54 *****************************************************************************/
  55 {
  56   AROS_LIBFUNC_INIT
  57
  58   return AttemptSemaphore(&l->Lock);
  59
  60   AROS_LIBFUNC_EXIT
  61 } /* AttemptLockLayerRom */