rom/utility/remnamedobject.c

   1 /*
   2     Copyright © 1995-2001, The AROS Development Team. All rights reserved.
   3     $Id$
   4
   5     Desc: RemNamedObject() - Remove a NamedObject from a NameSpace.
   6     Lang: english
   7 */
   8 #include <proto/exec.h>
   9 #include "intern.h"
  10
  11 /*****************************************************************************
  12
  13     NAME */
  14 #include <utility/name.h>
  15 #include <proto/utility.h>
  16
  17         AROS_LH2(void, RemNamedObject,
  18
  19 /*  SYNOPSIS */
  20         AROS_LHA(struct NamedObject *, object, A0),
  21         AROS_LHA(struct Message     *, message, A1),
  22
  23 /*  LOCATION */
  24         struct UtilityBase *, UtilityBase, 44, Utility)
  25
  26 /*  FUNCTION
  27         Remove a NamedObject from a namespace.
  28
  29         If the NamedObject cannot be removed at the time of this call, then
  30         the call will return without removing the NamedObject. It will
  31         mark the NamedObject as "waiting for removal".
  32
  33         When the NamedObject is ready to be freed, the supplied message
  34         will be ReplyMsg()'d with the message->mn_Node.ln_Name field
  35         containing either:
  36             - the address of the NamedObject that was removed. In this case
  37               you can free the NamedObject yourself.
  38             - NULL. In this case, another Task has freed the NamedObject,
  39               and you should not do so.
  40
  41     INPUTS
  42         object      -   The NamedObject to attempt to remove.
  43         message     -   The message to send. This message is a standard
  44                         Exec Message, which MUST have the mn_ReplyPort
  45                         field correctly set. The mn_Node.ln_Name field
  46                         will contain the address of the NamedObject or NULL
  47                         upon arrival at your port.
  48
  49     RESULT
  50         The NamedObject will be removed if possible, or marked for removal
  51         at the next best moment.
  52
  53     NOTES
  54         Since this function effectively does a ReleaseNamedObject(), you
  55         must have found this object first.
  56
  57     EXAMPLE
  58
  59     BUGS
  60
  61     SEE ALSO
  62         AttemptRemNamedObject(), AddNamedObject()
  63
  64     INTERNALS
  65         AttemptRemNamedObject() calls this function with a NULL message,
  66         expecting that we remove the object if possible, or just return.
  67
  68         ReleaseNamedObject() also calls this with a NULL message.
  69
  70     HISTORY
  71         29-10-95    digulla automatically created from
  72                             utility_lib.fd and clib/utility_protos.h
  73         11-08-96    iaint   Adapted for AROS for stuff I did earlier.
  74         09-02-1997  iaint   Improved Message handling.
  75
  76 *****************************************************************************/
  77 {
  78     AROS_LIBFUNC_INIT
  79
  80     struct NameSpace       *ns;
  81     struct IntNamedObject *no;
  82
  83     if(object)
  84     {
  85         no = GetIntNamedObject( object );
  86         ns = no->no_ParentSpace;
  87
  88         /* If ns == 0, then this node hasn't been added to anywhere */
  89         if( ns )
  90         {
  91             /* Whether we free now, or later, the message handling is
  92                the same. So we use the same code.
  93
  94                The Forbid() is to prevent two tasks from trying to
  95                attach a message at the same time.
  96             */
  97             Forbid();
  98
  99             if( message )
 100             {
 101                 if( no->no_FreeMessage == NULL)
 102                 {
 103                     /* This is the message, mark for later */
 104                     message->mn_Node.ln_Name = (STRPTR)object;
 105                     no->no_FreeMessage = message;
 106                 }
 107                 else
 108                 {
 109                     /* This message is not it, return NULL name. */
 110                     message->mn_Node.ln_Name = NULL;
 111                     ReplyMsg(message);
 112                 }
 113             }
 114
 115             Permit();
 116
 117             if(no->no_UseCount == 0)
 118             {
 119                 /* Ok, so we can remove the NamedObject */
 120                 ObtainSemaphore( &ns->ns_Lock );
 121
 122                 Remove( (struct Node *)&no->no_Node );
 123
 124                 if(no->no_FreeMessage)
 125                 {
 126                     ReplyMsg( no->no_FreeMessage );
 127                 }
 128                 ReleaseSemaphore( &ns->ns_Lock );
 129             }
 130
 131         } /* if ( ns ) */
 132
 133     } /* if( object ) */
 134
 135     AROS_LIBFUNC_EXIT
 136
 137 } /* RemNamedObject */