rom/graphics/gfxassociate.c

   1 /*
   2     Copyright © 1995-2010, The AROS Development Team. All rights reserved.
   3     $Id$
   4
   5     Desc:
   6     Lang: english
   7 */
   8
   9 #include <exec/types.h>
  10 #include <exec/memory.h>
  11 #include <graphics/gfxbase.h>
  12 #include <graphics/monitor.h>
  13 #include <graphics/view.h>
  14 #include <graphics/gfxnodes.h>
  15 #include <proto/exec.h>
  16 #include <proto/graphics.h>
  17 #include "graphics_intern.h"
  18
  19 /*****************************************************************************
  20
  21     NAME */
  22
  23       AROS_LH2( void , GfxAssociate,
  24
  25 /*  SYNOPSIS */
  26
  27       AROS_LHA( void *, pointer, A0),
  28       AROS_LHA( struct ExtendedNode *, node, A1),
  29
  30 /*  LOCATION */
  31
  32       struct GfxBase *, GfxBase, 112, Graphics)
  33
  34 /*  FUNCTION
  35       Associate a special graphics extended data structure with another
  36       structure via the other structure's pointer. Later, when you call
  37       GfxLookUp() with the other structure's pointer you may receive
  38       the pointer to this special graphics extended data structure, if it
  39       is available
  40
  41     INPUTS
  42       pointer = a pointer to a data structure
  43       node = an ExtendedNode structure to associate with the pointer
  44
  45     RESULT
  46       an association is created between the pointer and the node such
  47       that given the pointer the node can be retrieved via GfxLookUp().
  48
  49     NOTES
  50       Never associate one special graphics extended data structure to
  51       several pointers. Only one pointer is allowed!
  52
  53     EXAMPLE
  54
  55     BUGS
  56
  57     SEE ALSO
  58       graphics/gfxnodes.h, GfxFree(), GfxNew(), GfxLookUp()
  59
  60     INTERNALS
  61
  62     HISTORY
  63
  64 ******************************************************************************/
  65 {
  66     AROS_LIBFUNC_INIT
  67
  68     IPTR *Hash = GfxBase -> hash_table;
  69     ULONG Index = CalcHashIndex((IPTR)pointer, GFXASSOCIATE_HASHSIZE);
  70
  71     /* Whatever structure we get as node we put the pointer in the space
  72        following immediately after the ExtendedNode structure.
  73        ViewExtra -> View          is equal to
  74        ViewPortExtra -> ViewPort
  75     */
  76
  77     ((struct ViewExtra *)node) -> View = pointer;
  78     ObtainSemaphore(GfxBase->HashTableSemaphore);
  79
  80     /* Insert the structure into a hash_list which is to be found
  81        in the gfxlibrary */
  82     if (0 != Hash[Index])
  83         ((struct ExtendedNode *)Hash[Index]) -> xln_Pred = (struct Node *)node;
  84     node -> xln_Succ = (struct Node *)Hash[Index];
  85     node -> xln_Pred = (struct Node *)&Hash[Index];
  86     Hash[Index] = (IPTR)node;
  87
  88     ReleaseSemaphore(GfxBase->HashTableSemaphore);
  89
  90     AROS_LIBFUNC_EXIT
  91 } /* GfxAssociate */