gecko/content/smil/nsSMILInstanceTime.cpp

240 lines
7.2 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"
#include "nsSMILInterval.h"
#include "nsSMILTimeValueSpec.h"
//----------------------------------------------------------------------
// Helper classes
namespace
{
// Utility class to set a PRPackedBool value to PR_TRUE whilst it is in scope.
// Saves us having to remember to clear the flag at every possible return.
class AutoBoolSetter
{
public:
AutoBoolSetter(PRPackedBool& aValue)
: mValue(aValue)
{
mValue = PR_TRUE;
}
~AutoBoolSetter()
{
mValue = PR_FALSE;
}
private:
PRPackedBool& mValue;
};
}
//----------------------------------------------------------------------
// Implementation
nsSMILInstanceTime::nsSMILInstanceTime(const nsSMILTimeValue& aTime,
nsSMILInstanceTimeSource aSource,
nsSMILTimeValueSpec* aCreator,
nsSMILInterval* aBaseInterval)
: mTime(aTime),
mFlags(0),
mSerial(0),
mVisited(PR_FALSE),
mChainEnd(PR_FALSE),
mCreator(aCreator),
mBaseInterval(nsnull) // This will get set to aBaseInterval in a call to
// SetBaseInterval() at end of constructor
{
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;
}
SetBaseInterval(aBaseInterval);
}
nsSMILInstanceTime::~nsSMILInstanceTime()
{
NS_ABORT_IF_FALSE(!mBaseInterval && !mCreator,
"Destroying instance time without first calling Unlink()");
}
void
nsSMILInstanceTime::Unlink()
{
nsRefPtr<nsSMILInstanceTime> deathGrip(this);
if (mBaseInterval) {
mBaseInterval->RemoveDependentTime(*this);
mBaseInterval = nsnull;
}
mCreator = nsnull;
}
void
nsSMILInstanceTime::HandleChangedInterval(
const nsSMILTimeContainer* aSrcContainer,
PRBool aBeginObjectChanged,
PRBool aEndObjectChanged)
{
NS_ABORT_IF_FALSE(mBaseInterval,
"Got call to HandleChangedInterval on an independent instance time.");
NS_ABORT_IF_FALSE(mCreator, "Base interval is set but creator is not.");
if (mVisited || mChainEnd) {
// We're breaking the cycle here but we need to ensure that if we later
// receive a change notice in a different context (e.g. due to a time
// container change) that we don't end up following the chain further and so
// we set a flag to that effect.
mChainEnd = PR_TRUE;
return;
}
PRBool objectChanged = mCreator->DependsOnBegin() ? aBeginObjectChanged :
aEndObjectChanged;
AutoBoolSetter setVisited(mVisited);
nsRefPtr<nsSMILInstanceTime> deathGrip(this);
mCreator->HandleChangedInstanceTime(*GetBaseTime(), aSrcContainer, *this,
objectChanged);
}
void
nsSMILInstanceTime::HandleDeletedInterval()
{
NS_ABORT_IF_FALSE(mBaseInterval,
"Got call to HandleDeletedInterval on an independent instance time.");
NS_ABORT_IF_FALSE(mCreator, "Base interval is set but creator is not.");
mBaseInterval = nsnull;
nsRefPtr<nsSMILInstanceTime> deathGrip(this);
mCreator->HandleDeletedInstanceTime(*this);
mCreator = nsnull;
}
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");
const nsSMILInstanceTime* myBaseTime = GetBaseTime();
if (!myBaseTime)
return PR_FALSE;
if (myBaseTime == &aOther)
return PR_TRUE;
return myBaseTime->IsDependent(aOther, ++aRecursionDepth);
}
void
nsSMILInstanceTime::SetBaseInterval(nsSMILInterval* aBaseInterval)
{
NS_ABORT_IF_FALSE(!mBaseInterval,
"Attepting to reassociate an instance time with a different interval.");
// Make sure we don't end up creating a cycle between the dependent time
// pointers.
if (aBaseInterval) {
NS_ABORT_IF_FALSE(mCreator,
"Attempting to create a dependent instance time without reference "
"to the creating nsSMILTimeValueSpec object.");
if (!mCreator)
return;
const nsSMILInstanceTime* dependentTime = mCreator->DependsOnBegin() ?
aBaseInterval->Begin() :
aBaseInterval->End();
dependentTime->BreakPotentialCycle(this);
aBaseInterval->AddDependentTime(*this);
}
mBaseInterval = aBaseInterval;
}
const nsSMILInstanceTime*
nsSMILInstanceTime::GetBaseTime() const
{
if (!mBaseInterval) {
return nsnull;
}
NS_ABORT_IF_FALSE(mCreator, "Base interval is set but there is no creator.");
if (!mCreator) {
return nsnull;
}
return mCreator->DependsOnBegin() ? mBaseInterval->Begin() :
mBaseInterval->End();
}
void
nsSMILInstanceTime::BreakPotentialCycle(
const nsSMILInstanceTime* aNewTail) const
{
const nsSMILInstanceTime* myBaseTime = GetBaseTime();
if (!myBaseTime)
return;
if (myBaseTime == aNewTail) {
// Making aNewTail the new tail of the chain would create a cycle so we
// prevent this by unlinking the pointer to aNewTail.
mBaseInterval->RemoveDependentTime(*this);
return;
}
myBaseTime->BreakPotentialCycle(aNewTail);
}