workbench/libs/iffparse/entryhandler.c

   1 /*
   2     Copyright © 1995-2004, The AROS Development Team. All rights reserved.
   3     $Id$
   4 */
   5
   6 #define DEBUG 0
   7 #include <aros/debug.h>
   8 #include "iffparse_intern.h"
   9
  10 /*****************************************************************************
  11
  12     NAME */
  13 #include <proto/iffparse.h>
  14
  15         AROS_LH6(LONG, EntryHandler,
  16
  17 /*  SYNOPSIS */
  18         AROS_LHA(struct IFFHandle *, iff, A0),
  19         AROS_LHA(LONG              , type, D0),
  20         AROS_LHA(LONG              , id, D1),
  21         AROS_LHA(LONG              , position, D2),
  22         AROS_LHA(struct Hook      *, handler, A1),
  23         AROS_LHA(APTR              , object, A2),
  24
  25 /*  LOCATION */
  26         struct Library *, IFFParseBase, 17, IFFParse)
  27
  28 /*  FUNCTION
  29         Installs an entry handler for a specific chunk type
  30         that wil be called whenever a chunk of that type is pushed on the contextstack
  31         via ParseIFF().
  32
  33
  34     INPUTS
  35         iff         - pointer to an iffhandle struct.
  36         type      - type code for the chunk to handle. (ex: "ILBM").
  37         id        -  ID code for the chunk to handle. (ex: "CMAP")
  38         position  -  position of localcontextitem. See StoreLocalItem for
  39                     more info.
  40         handler    -  an initialised Hook structure for the handler function.
  41         object    -  pointer to some kind of object that will be passed to
  42                     your handler function.
  43
  44     RESULT
  45         error - 0 If successfull, IFFERR_#? elsewise.
  46
  47     NOTES
  48
  49     EXAMPLE
  50
  51     BUGS
  52
  53     SEE ALSO
  54         ExitHandler(), StoreLocalItem(), StoreItemInContext()
  55
  56
  57
  58     INTERNALS
  59
  60 *****************************************************************************/
  61 {
  62     AROS_LIBFUNC_INIT
  63     AROS_LIBBASE_EXT_DECL(struct Library *,IFFParseBase)
  64
  65     struct LocalContextItem *lci;
  66     struct HandlerInfo *hi;
  67
  68     D(bug ("EntryHandler (iff=%p, type=%c%c%c%c, id=%c%c%c%c, position=%d, handler=%p, object=%p)\n",
  69         iff,
  70         dmkid(type),
  71         dmkid(id),
  72         position, handler, object
  73     ));
  74
  75     if (!(lci = AllocLocalItem(
  76                 type,
  77                 id,
  78                 IFFLCI_ENTRYHANDLER,
  79                 sizeof (struct HandlerInfo))))
  80     {
  81         ReturnInt ("EntryHandler",LONG,IFFERR_NOMEM);
  82     }
  83
  84     /* Get pointer to the user data */
  85     hi = LocalItemData(lci);
  86
  87     hi->hi_Hook  = handler;
  88
  89     hi->hi_Object  = object;
  90
  91     ReturnInt
  92     (
  93         "EntryHandler",
  94         LONG,
  95         StoreLocalItem
  96         (
  97             iff,
  98             lci,
  99             position
 100         )
 101     );
 102
 103     AROS_LIBFUNC_EXIT
 104 } /* EntryHandler */