gecko-dev/dom/smil/nsSMILValue.cpp

163 lines
4.1 KiB
C++

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#include "nsSMILValue.h"
#include "nsDebug.h"
#include <string.h>
//----------------------------------------------------------------------
// Public methods
nsSMILValue::nsSMILValue(const nsISMILType* aType)
: mType(nsSMILNullType::Singleton())
{
if (!aType) {
NS_ERROR("Trying to construct nsSMILValue with null mType pointer");
return;
}
InitAndCheckPostcondition(aType);
}
nsSMILValue::nsSMILValue(const nsSMILValue& aVal)
: mType(nsSMILNullType::Singleton())
{
InitAndCheckPostcondition(aVal.mType);
mType->Assign(*this, aVal);
}
const nsSMILValue&
nsSMILValue::operator=(const nsSMILValue& aVal)
{
if (&aVal == this)
return *this;
if (mType != aVal.mType) {
DestroyAndReinit(aVal.mType);
}
mType->Assign(*this, aVal);
return *this;
}
// Move constructor / reassignment operator:
nsSMILValue::nsSMILValue(nsSMILValue&& aVal)
: mU(aVal.mU), // Copying union is only OK because we clear aVal.mType below.
mType(aVal.mType)
{
// Leave aVal with a null type, so that it's safely destructible (and won't
// mess with anything referenced by its union, which we've copied).
aVal.mType = nsSMILNullType::Singleton();
}
nsSMILValue&
nsSMILValue::operator=(nsSMILValue&& aVal)
{
if (!IsNull()) {
// Clean up any data we're currently tracking.
DestroyAndCheckPostcondition();
}
// Copy the union (which could include a pointer to external memory) & mType:
mU = aVal.mU;
mType = aVal.mType;
// Leave aVal with a null type, so that it's safely destructible (and won't
// mess with anything referenced by its union, which we've now copied).
aVal.mType = nsSMILNullType::Singleton();
return *this;
}
bool
nsSMILValue::operator==(const nsSMILValue& aVal) const
{
if (&aVal == this)
return true;
return mType == aVal.mType && mType->IsEqual(*this, aVal);
}
nsresult
nsSMILValue::Add(const nsSMILValue& aValueToAdd, uint32_t aCount)
{
if (aValueToAdd.mType != mType) {
NS_ERROR("Trying to add incompatible types");
return NS_ERROR_FAILURE;
}
return mType->Add(*this, aValueToAdd, aCount);
}
nsresult
nsSMILValue::SandwichAdd(const nsSMILValue& aValueToAdd)
{
if (aValueToAdd.mType != mType) {
NS_ERROR("Trying to add incompatible types");
return NS_ERROR_FAILURE;
}
return mType->SandwichAdd(*this, aValueToAdd);
}
nsresult
nsSMILValue::ComputeDistance(const nsSMILValue& aTo, double& aDistance) const
{
if (aTo.mType != mType) {
NS_ERROR("Trying to calculate distance between incompatible types");
return NS_ERROR_FAILURE;
}
return mType->ComputeDistance(*this, aTo, aDistance);
}
nsresult
nsSMILValue::Interpolate(const nsSMILValue& aEndVal,
double aUnitDistance,
nsSMILValue& aResult) const
{
if (aEndVal.mType != mType) {
NS_ERROR("Trying to interpolate between incompatible types");
return NS_ERROR_FAILURE;
}
if (aResult.mType != mType) {
// Outparam has wrong type
aResult.DestroyAndReinit(mType);
}
return mType->Interpolate(*this, aEndVal, aUnitDistance, aResult);
}
//----------------------------------------------------------------------
// Helper methods
// Wrappers for nsISMILType::Init & ::Destroy that verify their postconditions
void
nsSMILValue::InitAndCheckPostcondition(const nsISMILType* aNewType)
{
aNewType->Init(*this);
MOZ_ASSERT(mType == aNewType,
"Post-condition of Init failed. nsSMILValue is invalid");
}
void
nsSMILValue::DestroyAndCheckPostcondition()
{
mType->Destroy(*this);
MOZ_ASSERT(IsNull(),
"Post-condition of Destroy failed. "
"nsSMILValue not null after destroying");
}
void
nsSMILValue::DestroyAndReinit(const nsISMILType* aNewType)
{
DestroyAndCheckPostcondition();
InitAndCheckPostcondition(aNewType);
}