gecko-dev/content/smil/nsSMILInstanceTime.cpp

119 lines
3.9 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 the Mozilla SMIL module.
*
* The Initial Developer of the Original Code is Brian Birtles.
* Portions created by the Initial Developer are Copyright (C) 2005
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
* Brian Birtles <birtles@gmail.com>
*
* 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 ***** */
#include "nsSMILInstanceTime.h"
nsSMILInstanceTime::nsSMILInstanceTime(const nsSMILTimeValue& aTime,
const nsSMILInstanceTime* aDependentTime,
nsSMILInstanceTimeSource aSource)
: mTime(aTime),
mFlags(0),
mSerial(0)
{
switch (aSource) {
case SOURCE_NONE:
// No special flags
break;
case SOURCE_DOM:
mFlags = kClearOnReset | kFromDOM;
break;
case SOURCE_SYNCBASE:
mFlags = kMayUpdate;
break;
case SOURCE_EVENT:
mFlags = kClearOnReset;
break;
}
SetDependentTime(aDependentTime);
}
void
nsSMILInstanceTime::SetDependentTime(const nsSMILInstanceTime* aDependentTime)
{
// We must make the dependent time mutable because our ref-counting isn't
// const-correct and BreakPotentialCycle may update dependencies (which should
// be considered 'mutable')
nsSMILInstanceTime* mutableDependentTime =
const_cast<nsSMILInstanceTime*>(aDependentTime);
// Make sure we don't end up creating a cycle between the dependent time
// pointers. (Note that this is not the same as detecting syncbase dependency
// cycles. That is done by nsSMILTimeValueSpec. mDependentTime is used ONLY
// for ensuring correct ordering within the animation sandwich.)
if (aDependentTime) {
mutableDependentTime->BreakPotentialCycle(this);
}
mDependentTime = mutableDependentTime;
}
void
nsSMILInstanceTime::BreakPotentialCycle(const nsSMILInstanceTime* aNewTail)
{
if (!mDependentTime)
return;
if (mDependentTime == aNewTail) {
// Making aNewTail the new tail of the chain would create a cycle so we
// prevent this by unlinking the pointer to aNewTail.
mDependentTime = nsnull;
return;
}
mDependentTime->BreakPotentialCycle(aNewTail);
}
PRBool
nsSMILInstanceTime::IsDependent(const nsSMILInstanceTime& aOther,
PRUint32 aRecursionDepth) const
{
NS_ABORT_IF_FALSE(aRecursionDepth < 1000,
"We seem to have created a cycle between instance times");
if (!mDependentTime)
return PR_FALSE;
if (mDependentTime == &aOther)
return PR_TRUE;
return mDependentTime->IsDependent(aOther, ++aRecursionDepth);
}