1/*
2 * Copyright (C) 2003, 2006 Apple Computer, Inc.  All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 * 1. Redistributions of source code must retain the above copyright
8 *    notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 *    notice, this list of conditions and the following disclaimer in the
11 *    documentation and/or other materials provided with the distribution.
12 *
13 * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY
14 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
16 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE COMPUTER, INC. OR
17 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
18 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
19 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
20 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
21 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
23 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24 */
25
26#ifndef npruntime_priv_h
27#define npruntime_priv_h
28
29#include <bindings/npruntime.h>
30
31#ifdef __cplusplus
32extern "C" {
33#endif
34
35/*
36    _NPN_InitializeVariantWithStringCopy() will copy string data.  The string data
37    will be deallocated by calls to NPReleaseVariantValue().
38*/
39void _NPN_InitializeVariantWithStringCopy(NPVariant*, const NPString*);
40void _NPN_DeallocateObject(NPObject*);
41
42// The following routines allow the browser to aggressively cleanup NPObjects
43// on a per plugin basis.  All NPObjects used through the NPRuntime API should
44// be "registered" while they are alive.  After an object has been
45// deleted, it is possible for Javascript to have a reference to that object
46// which has not yet been garbage collected.  Javascript access to NPObjects
47// will reference this registry to determine if the object is accessible or
48// not.
49
50// Windows introduces an additional complication for objects created by the
51// plugin.  Plugins load inside of a DLL.  Each DLL has it's own heap.  If
52// the browser unloads the plugin DLL, all objects created within the DLL's
53// heap instantly become invalid.  Normally, when WebKit drops the reference
54// on the top-level plugin object, it tells the plugin manager that the
55// plugin can be destroyed, which can unload the DLL.  So, we must eliminate
56// all pointers to any object ever created by the plugin.
57
58// We generally associate NPObjects with an owner.  The owner of an NPObject
59// is an NPObject which, when destroyed, also destroys all objects it owns.
60// For example, if an NPAPI plugin creates 10 sub-NPObjects, all 11 objects
61// (the NPAPI plugin + its 10 sub-objects) should become inaccessible
62// simultaneously.
63
64// The ownership hierarchy is flat, and not a tree.  Imagine the following
65// object creation:
66//     PluginObject
67//          |
68//          +-- Creates -----> Object1
69//                                |
70//                                +-- Creates -----> Object2
71//
72// PluginObject will be the "owner" for both Object1 and Object2.
73
74// Register an NPObject with the runtime.  If the owner is NULL, the
75// object is treated as an owning object.  If owner is not NULL,
76// this object will be registered as owned by owner's top-level owner.
77void _NPN_RegisterObject(NPObject*, NPObject* owner);
78
79// Unregister an NPObject with the runtime.  If obj is an owning
80// object, this call will also unregister all of the owned objects.
81void _NPN_UnregisterObject(NPObject*);
82
83// Check to see if an object is registered with the runtime.
84// Return true if registered, false otherwise.
85bool _NPN_IsAlive(NPObject*);
86
87#ifdef __cplusplus
88}  /* end extern "C" */
89#endif
90
91#endif // npruntime_priv_h
92