mirror of
https://github.com/mozilla/gecko-dev.git
synced 2024-12-09 14:28:25 +00:00
232 lines
8.3 KiB
C++
232 lines
8.3 KiB
C++
/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
|
|
/* ***** BEGIN LICENSE BLOCK *****
|
|
* Version: MPL 1.1/GPL 2.0/LGPL 2.1
|
|
*
|
|
* The contents of this file are subject to the Mozilla Public License Version
|
|
* 1.1 (the "License"); you may not use this file except in compliance with
|
|
* the License. You may obtain a copy of the License at
|
|
* http://www.mozilla.org/MPL/
|
|
*
|
|
* Software distributed under the License is distributed on an "AS IS" basis,
|
|
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
|
|
* for the specific language governing rights and limitations under the
|
|
* License.
|
|
*
|
|
* The Original Code is mozilla.org code.
|
|
*
|
|
* The Initial Developer of the Original Code is
|
|
* Netscape Communications Corporation.
|
|
* Portions created by the Initial Developer are Copyright (C) 2005
|
|
* the Initial Developer. All Rights Reserved.
|
|
*
|
|
* Contributor(s):
|
|
* Mark Hammond <mhammond@skippinet.com.au>
|
|
*
|
|
* Alternatively, the contents of this file may be used under the terms of
|
|
* either of the GNU General Public License Version 2 or later (the "GPL"),
|
|
* or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
|
|
* in which case the provisions of the GPL or the LGPL are applicable instead
|
|
* of those above. If you wish to allow use of your version of this file only
|
|
* under the terms of either the GPL or the LGPL, and not to allow others to
|
|
* use your version of this file under the terms of the MPL, indicate your
|
|
* decision by deleting the provisions above and replace them with the notice
|
|
* and other provisions required by the GPL or the LGPL. If you do not delete
|
|
* the provisions above, a recipient may use your version of this file under
|
|
* the terms of any one of the MPL, the GPL or the LGPL.
|
|
*
|
|
* ***** END LICENSE BLOCK ***** */
|
|
|
|
#ifndef nsDOMScriptObjectHolder_h__
|
|
#define nsDOMScriptObjectHolder_h__
|
|
|
|
#include "nsIScriptRuntime.h"
|
|
#include "nsIDOMScriptObjectFactory.h"
|
|
|
|
class nsIScriptContext;
|
|
|
|
// Drop a reference to a script object when all you have is the script
|
|
// language ID.
|
|
inline nsresult NS_DropScriptObject(PRUint32 aLangID, void *aThing)
|
|
{
|
|
nsresult rv;
|
|
nsCOMPtr<nsIScriptRuntime> scriptRT;
|
|
NS_DEFINE_CID(cid, NS_DOM_SCRIPT_OBJECT_FACTORY_CID);
|
|
|
|
nsCOMPtr<nsIDOMScriptObjectFactory> factory = do_GetService(cid, &rv);
|
|
if (NS_SUCCEEDED(rv))
|
|
rv = factory->GetScriptRuntimeByID(aLangID, getter_AddRefs(scriptRT));
|
|
if (NS_SUCCEEDED(rv))
|
|
rv = scriptRT->DropScriptObject(aThing);
|
|
if (NS_FAILED(rv))
|
|
NS_ERROR("Failed to drop the script object");
|
|
return rv;
|
|
}
|
|
|
|
// Hold a reference to a script object when all you have is the script
|
|
// language ID, and you need to take a copy of the void script object.
|
|
// Must be matched by an NS_DropScriptObject
|
|
inline nsresult NS_HoldScriptObject(PRUint32 aLangID, void *aThing)
|
|
{
|
|
nsresult rv;
|
|
nsCOMPtr<nsIScriptRuntime> scriptRT;
|
|
NS_DEFINE_CID(cid, NS_DOM_SCRIPT_OBJECT_FACTORY_CID);
|
|
|
|
nsCOMPtr<nsIDOMScriptObjectFactory> factory = do_GetService(cid, &rv);
|
|
if (NS_SUCCEEDED(rv))
|
|
rv = factory->GetScriptRuntimeByID(aLangID, getter_AddRefs(scriptRT));
|
|
if (NS_SUCCEEDED(rv))
|
|
rv = scriptRT->HoldScriptObject(aThing);
|
|
if (NS_FAILED(rv))
|
|
NS_ERROR("Failed to hold the script object");
|
|
return rv;
|
|
}
|
|
|
|
// A thin class used to help with script object memory management. No virtual
|
|
// functions and a fully inline implementation should keep the cost down.
|
|
// [Note that a fully inline implementation is necessary for use by other
|
|
// languages, which do not link against the layout component module]
|
|
class nsScriptObjectHolder {
|
|
public:
|
|
// A constructor that will cause a reference to |ctx| to be stored in
|
|
// the object. Only use for short-lived object holders.
|
|
nsScriptObjectHolder(nsIScriptContext *ctx, void *aObject = nsnull) :
|
|
mObject(aObject), mContextOrLangID(NS_REINTERPRET_CAST(PtrBits, ctx)) {
|
|
NS_ASSERTION(ctx, "Must provide a valid context");
|
|
NS_ADDREF(ctx);
|
|
}
|
|
|
|
// A constructor that stores only the integer language ID - freeing the
|
|
// script object is slower in this case, but is safe for long-lived
|
|
// object holders.
|
|
nsScriptObjectHolder(PRUint32 aLangID, void *aObject = nsnull) :
|
|
mObject(aObject),
|
|
mContextOrLangID((aLangID << 1) | SOH_HAS_LANGID_BIT) {
|
|
NS_ASSERTION(aLangID != nsIProgrammingLanguage::UNKNOWN,
|
|
"Please supply a valid language ID");
|
|
}
|
|
|
|
// copy constructor
|
|
nsScriptObjectHolder(const nsScriptObjectHolder& other) :
|
|
mObject(other.mObject),
|
|
mContextOrLangID(other.mContextOrLangID)
|
|
{
|
|
if (mContextOrLangID & SOH_HAS_LANGID_BIT) {
|
|
if (mObject) {
|
|
NS_HoldScriptObject(getScriptTypeIDFromBits(), mObject);
|
|
}
|
|
} else {
|
|
// New hold the script object and new reference on the script context.
|
|
nsIScriptContext *ctx = NS_REINTERPRET_CAST(nsIScriptContext *,
|
|
mContextOrLangID);
|
|
NS_ASSERTION(ctx, "Lost context pointer?");
|
|
NS_ADDREF(ctx);
|
|
if (mObject)
|
|
ctx->HoldScriptObject(mObject);
|
|
}
|
|
}
|
|
|
|
~nsScriptObjectHolder() {
|
|
// If we have a language ID, then we only need to NS_DropScriptObject if
|
|
// we are holding a script object.
|
|
// If we have a script context, we must always release our reference to it,
|
|
// even if we are not holding a script object.
|
|
if (mContextOrLangID & SOH_HAS_LANGID_BIT) {
|
|
if (mObject) {
|
|
NS_DropScriptObject(getScriptTypeIDFromBits(), mObject);
|
|
}
|
|
} else {
|
|
nsIScriptContext *ctx = NS_REINTERPRET_CAST(nsIScriptContext *,
|
|
mContextOrLangID);
|
|
NS_ASSERTION(ctx, "Lost context pointer?");
|
|
if (mObject) {
|
|
ctx->DropScriptObject(mObject);
|
|
}
|
|
NS_IF_RELEASE(ctx);
|
|
}
|
|
}
|
|
|
|
// misc operators
|
|
nsScriptObjectHolder &operator=(const nsScriptObjectHolder &other) {
|
|
set(other);
|
|
return *this;
|
|
}
|
|
PRBool operator!() const {
|
|
return !mObject;
|
|
}
|
|
operator void *() const {
|
|
return mObject;
|
|
}
|
|
|
|
// Drop the script object - but *not* the nsIScriptContext nor the language
|
|
// ID.
|
|
nsresult drop() {
|
|
nsresult rv = NS_OK;
|
|
if (mObject) {
|
|
if (mContextOrLangID & SOH_HAS_LANGID_BIT) {
|
|
rv = NS_DropScriptObject(getScriptTypeIDFromBits(), mObject);
|
|
} else {
|
|
nsIScriptContext *ctx = NS_REINTERPRET_CAST(nsIScriptContext *,
|
|
mContextOrLangID);
|
|
NS_ASSERTION(ctx, "Lost ctx pointer!");
|
|
rv = ctx->DropScriptObject(mObject);
|
|
}
|
|
mObject = nsnull;
|
|
}
|
|
return rv;
|
|
}
|
|
nsresult set(void *object) {
|
|
NS_ASSERTION(getScriptTypeID() != nsIProgrammingLanguage::UNKNOWN,
|
|
"Must know the language!");
|
|
nsresult rv = drop();
|
|
if (NS_FAILED(rv))
|
|
return rv;
|
|
if (object) {
|
|
if (mContextOrLangID & SOH_HAS_LANGID_BIT) {
|
|
rv = NS_HoldScriptObject(getScriptTypeIDFromBits(), object);
|
|
} else {
|
|
nsIScriptContext *ctx = NS_REINTERPRET_CAST(nsIScriptContext *,
|
|
mContextOrLangID);
|
|
rv = ctx->HoldScriptObject(object);
|
|
}
|
|
// don't store the pointer if we failed to lock it.
|
|
if (NS_SUCCEEDED(rv)) {
|
|
mObject = object;
|
|
}
|
|
}
|
|
return rv;
|
|
}
|
|
nsresult set(const nsScriptObjectHolder &other) {
|
|
NS_ASSERTION(getScriptTypeID() == other.getScriptTypeID(),
|
|
"Must have identical languages!");
|
|
nsresult rv = drop();
|
|
if (NS_FAILED(rv))
|
|
return rv;
|
|
return set(other.mObject);
|
|
}
|
|
// Get the language ID.
|
|
PRUint32 getScriptTypeID() const {
|
|
if (mContextOrLangID & SOH_HAS_LANGID_BIT) {
|
|
return getScriptTypeIDFromBits();
|
|
}
|
|
nsIScriptContext *ctx = NS_REINTERPRET_CAST(nsIScriptContext *,
|
|
mContextOrLangID);
|
|
NS_ASSERTION(ctx, "How did I lose my pointer?");
|
|
return ctx->GetScriptTypeID();
|
|
}
|
|
protected:
|
|
PRUint32 getScriptTypeIDFromBits() const {
|
|
NS_ASSERTION(mContextOrLangID & SOH_HAS_LANGID_BIT, "Not in the bits!");
|
|
return (mContextOrLangID & ~SOH_HAS_LANGID_BIT) >> 1;
|
|
}
|
|
void *mObject;
|
|
// We store either an nsIScriptContext* if this bit is clear,
|
|
// else the language ID (specifically, ((lang_id << 1) | SOH_HAS_LANGID_BIT)
|
|
// when set.
|
|
typedef PRWord PtrBits;
|
|
enum { SOH_HAS_LANGID_BIT = 0x1 };
|
|
|
|
PtrBits mContextOrLangID;
|
|
};
|
|
|
|
#endif // nsDOMScriptObjectHolder_h__
|