workbench/libs/iffparse/exithandler.c

   1 /*
   2     Copyright © 1995-2016, 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, ExitHandler,
  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, 18, IFFParse)
  27
  28 /*  FUNCTION
  29         Installs an exit handler for a specific chunk type
  30         that wil be called whenever a chunk of that type is popped off 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 successful, IFFERR_#? otherwise.
  46
  47     NOTES
  48
  49     EXAMPLE
  50
  51     BUGS
  52
  53     SEE ALSO
  54          EntryHandler(), StoreLocalItem(), StoreItemInContext()
  55
  56     INTERNALS
  57
  58 *****************************************************************************/
  59 {
  60     AROS_LIBFUNC_INIT
  61
  62     struct LocalContextItem *lci;
  63     struct HandlerInfo *hi;
  64
  65     D(bug ("ExitHandler (iff=%p, type=%c%c%c%c, id=%c%c%c%c, position=%d, handler=%p, object=%p)\n",
  66         iff,
  67         dmkid(type),
  68         dmkid(id),
  69         position, handler, object
  70     ));
  71
  72     if (!(lci = AllocLocalItem(
  73                 type,
  74                 id,
  75                 IFFLCI_EXITHANDLER,
  76                 sizeof (struct HandlerInfo))))
  77     {
  78         D(bug("ExitHandler: return IFFERR_NOME\n"));
  79         return (IFFERR_NOMEM);
  80     }
  81
  82     /* Get pointer to the user contining a HandlerInfo structure data */
  83     hi = LocalItemData(lci);
  84
  85     hi->hi_Hook  = handler;
  86
  87     hi->hi_Object  = object;
  88
  89     return
  90     (
  91         StoreLocalItem
  92         (
  93             iff,
  94             lci,
  95             position
  96         )
  97     );
  98
  99
 100     AROS_LIBFUNC_EXIT
 101 } /* ExitHandler */