workbench/libs/iffparse/parentchunk.c

   1 /*
   2     Copyright © 1995-2004, The AROS Development Team. All rights reserved.
   3     $Id$
   4 */
   5
   6 #include "iffparse_intern.h"
   7
   8 /*****************************************************************************
   9
  10     NAME */
  11 #include <proto/iffparse.h>
  12
  13         AROS_LH1(struct ContextNode *, ParentChunk,
  14
  15 /*  SYNOPSIS */
  16         AROS_LHA(struct ContextNode *, contextNode, A0),
  17
  18 /*  LOCATION */
  19         struct Library *, IFFParseBase, 30, IFFParse)
  20
  21 /*  FUNCTION
  22         Returns a pointer to the parent context node to the given
  23         one on the context node stack. The parent context node
  24         represents the chunk enclosing the chunk given.
  25         This can be use together with CurrentChunk() to iterate the
  26         context node stack top-down.
  27
  28     INPUTS
  29         contextNode  - pointer to a context node.
  30
  31     RESULT
  32         parent      -  pointer to the parent context node or NULL if none.
  33
  34     NOTES
  35
  36     EXAMPLE
  37
  38     BUGS
  39
  40     SEE ALSO
  41         CurrentChunk()
  42
  43     INTERNALS
  44
  45 *****************************************************************************/
  46 {
  47     AROS_LIBFUNC_INIT
  48     AROS_LIBBASE_EXT_DECL(struct Library *,IFFParseBase)
  49
  50     struct ContextNode *parentcn;
  51
  52     (void) IFFParseBase;
  53
  54     /* Get the parent of this contextnode. The contextstack
  55       is simulated via AddHead/RemHead so we should use
  56       .mln_Succ to get the parent
  57     */
  58     parentcn = (struct ContextNode*)contextNode->cn_Node.mln_Succ;
  59
  60     /* If the parent of the found node is 0 (mlh_Tail field
  61        in struct MinList, then parentcn is the default contextnode,
  62        which the user not should have access to
  63     */
  64
  65     if (!parentcn->cn_Node.mln_Succ)
  66         parentcn = NULL;
  67
  68     return (parentcn);
  69
  70     AROS_LIBFUNC_EXIT
  71 } /* ParentChunk */