import FIREFOX_52_6_0esr_RELEASE from mozilla-esr52 hg repo

dom/smil/nsSMILValue.cpp

@@ -0,0 +1,162 @@
+/* -*- 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);
+}