rom/graphics/locklayerrom.c

   1 /*
   2     Copyright © 1995-2001, The AROS Development Team. All rights reserved.
   3     $Id$
   4
   5     Desc: Graphics function LockLayerRom()
   6     Lang: english
   7 */
   8 #include <proto/layers.h>
   9 #include <proto/exec.h>
  10 #include <graphics/clip.h>
  11
  12 /*****************************************************************************
  13
  14     NAME */
  15 #include <proto/graphics.h>
  16
  17         AROS_LH1(void, LockLayerRom,
  18
  19 /*  SYNOPSIS */
  20         AROS_LHA(struct Layer *, l,   A5),
  21
  22 /*  LOCATION */
  23         struct GfxBase *, GfxBase, 72, Graphics)
  24
  25 /*  FUNCTION
  26         Locks the layer. Returns when the layer is locked for
  27         exclusive use.
  28         This call behaves like when a semaphore is locked. The
  29         same task may lock the same layer several times without
  30         locking itself out. For every call to this function a
  31         call to UnlockLayerRom() has to be made as the calls nest.
  32         This function will also prevent intuition from locking the
  33         layer so the layer should not be blocked too long.
  34         This function does exactly the same as layers/LockLayer()
  35
  36     INPUTS
  37         l - pointer to layer that is to be locked
  38
  39     RESULT
  40
  41     NOTES
  42
  43     EXAMPLE
  44
  45     BUGS
  46        Does not save all registers.
  47
  48     SEE ALSO
  49        UnlockLayerRom() LockLayer() UnLockLayer()
  50
  51     INTERNALS
  52
  53     HISTORY
  54
  55 *****************************************************************************/
  56 {
  57   AROS_LIBFUNC_INIT
  58   AROS_LIBBASE_EXT_DECL(struct GfxBase *,GfxBase)
  59
  60   ObtainSemaphore(&l->Lock);
  61
  62   AROS_LIBFUNC_EXIT
  63 } /* LockLayerRom */