gecko-dev/toolkit/content/XPCNativeWrapper.js

105 lines
3.8 KiB
JavaScript

/* ***** 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 XPConnect Native Wrapper.
*
* The Initial Developer of the Original Code is
* Christopher A. Aillon <christopher@aillon.com>.
* Portions created by the Initial Developer are Copyright (C) 2002
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
* Christopher A. Aillon <christopher@aillon.com>
*
* Alternatively, the contents of this file may be used under the terms of
* either 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 ***** */
/**
* Get a wrapper to certain XPConnect wrapped native properties of an
* untrusted object.
*
* Usage:
* var wrapper = new XPCNativeWrapper(untrusted, 'title', 'getElementById()');
* var title = wrapper.title;
* var elem = wrapper.getElementById('fooId');
*
* @param aUntrustedObject the untrusted object we want native wrappers for
* @param arg1...argN strings of the form 'property' or 'method()' which
* denote the property or method names we wish to wrap
* @throws NS_ERROR_XPC_BAD_CONVERT_JS if a property or method requested
* does not have a native wrapper on
* the untrusted object.
* @see nsXPCComponents::LookupMethod()
*/
function XPCNativeWrapper(aUntrustedObject)
{
this.mUntrustedObject = aUntrustedObject;
for (var i = arguments.length - 1; i > 0; --i)
this.importXPCNative(arguments[i]);
}
XPCNativeWrapper.prototype =
{
importXPCNative:
function(aName)
{
// If we are passed a string like "foo()", ary[2] will be of type string,
// and contain "()". If passed "foo", then it will be of type undefined.
if (aName.slice(-2) == "()")
this._doImportMethod(aName.slice(0, -2));
else
this._doImportProperty(aName);
},
_doImportMethod:
function(aMethodName)
{
var nativeMethod = Components.lookupMethod(this.mUntrustedObject,
aMethodName);
this[aMethodName] = function()
{
return nativeMethod.apply(this.mUntrustedObject, arguments);
};
},
_doImportProperty:
function(aPropName)
{
var nativeMethod = Components.lookupMethod(this.mUntrustedObject,
aPropName);
var theGetter = function()
{
return nativeMethod.call(this.mUntrustedObject);
};
var theSetter = function(val)
{
return nativeMethod.call(this.mUntrustedObject, val);
};
this.__defineGetter__(aPropName, theGetter);
this.__defineSetter__(aPropName, theSetter);
}
};