firefox-main/dom/base/nsPropertyTable.cpp (file symbol)

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/* 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/. */
/**
* nsPropertyTable allows a set of arbitrary key/value pairs to be stored
* for any number of nodes, in a global hashtable rather than on the nodes
* themselves. Nodes can be any type of object; the hashtable keys are
* nsAtom pointers, and the values are void pointers.
*/
#include "nsPropertyTable.h"
#include "mozilla/MemoryReporting.h"
#include "nsAtom.h"
#include "nsError.h"
#include "nsTHashMap.h"
//----------------------------------------------------------------------
class nsPropertyTable::PropertyList {
public:
PropertyList(nsAtom* aName, NSPropertyDtorFunc aDtorFunc, void* aDtorData,
bool aTransfer);
~PropertyList();
// Removes the property associated with the given object, and destroys
// the property value
bool RemovePropertyFor(nsPropertyOwner aObject);
// Destroy all remaining properties (without removing them)
void Destroy();
bool Equals(const nsAtom* aPropertyName) { return mName == aPropertyName; }
size_t SizeOfIncludingThis(mozilla::MallocSizeOf aMallocSizeOf);
RefPtr<nsAtom> mName; // property name
nsTHashMap<const void*, void*> mObjectValueMap; // map of object/value pairs
NSPropertyDtorFunc mDtorFunc; // property specific value dtor function
void* mDtorData; // pointer to pass to dtor
bool mTransfer; // whether to transfer in
// TransferOrRemoveAllPropertiesFor
PropertyList* mNext;
};
void nsPropertyTable::RemoveAllProperties() {
while (mPropertyList) {
PropertyList* tmp = mPropertyList;
mPropertyList = mPropertyList->mNext;
tmp->Destroy();
delete tmp;
}
}
void nsPropertyTable::RemoveAllPropertiesFor(nsPropertyOwner aObject) {
for (PropertyList* prop = mPropertyList; prop; prop = prop->mNext) {
prop->RemovePropertyFor(aObject);
}
}
nsresult nsPropertyTable::TransferOrRemoveAllPropertiesFor(
nsPropertyOwner aObject, nsPropertyTable& aOtherTable) {
nsresult rv = NS_OK;
for (PropertyList* prop = mPropertyList; prop; prop = prop->mNext) {
if (prop->mTransfer) {
auto entry = prop->mObjectValueMap.Lookup(aObject);
if (entry) {
rv = aOtherTable.SetProperty(aObject, prop->mName, entry.Data(),
prop->mDtorFunc, prop->mDtorData,
prop->mTransfer);
if (NS_FAILED(rv)) {
RemoveAllPropertiesFor(aObject);
aOtherTable.RemoveAllPropertiesFor(aObject);
break;
}
entry.Remove();
}
} else {
prop->RemovePropertyFor(aObject);
}
}
return rv;
}
void nsPropertyTable::Enumerate(nsPropertyOwner aObject,
NSPropertyFunc aCallback, void* aData) {
PropertyList* prop;
for (prop = mPropertyList; prop; prop = prop->mNext) {
auto entry = prop->mObjectValueMap.Lookup(aObject);
if (entry) {
aCallback(const_cast<void*>(aObject.get()), prop->mName, entry.Data(),
aData);
}
}
}
void nsPropertyTable::EnumerateAll(NSPropertyFunc aCallBack, void* aData) {
for (PropertyList* prop = mPropertyList; prop; prop = prop->mNext) {
for (const auto& entry : prop->mObjectValueMap) {
aCallBack(const_cast<void*>(entry.GetKey()), prop->mName, entry.GetData(),
aData);
}
}
}
void* nsPropertyTable::GetPropertyInternal(nsPropertyOwner aObject,
const nsAtom* aPropertyName,
bool aRemove, nsresult* aResult) {
MOZ_ASSERT(aPropertyName && aObject, "unexpected null param");
nsresult rv = NS_PROPTABLE_PROP_NOT_THERE;
void* propValue = nullptr;
PropertyList* propertyList = GetPropertyListFor(aPropertyName);
if (propertyList) {
auto entry = propertyList->mObjectValueMap.Lookup(aObject);
if (entry) {
propValue = entry.Data();
if (aRemove) {
// don't call propertyList->mDtorFunc. That's the caller's job now.
entry.Remove();
}
rv = NS_OK;
}
}
if (aResult) *aResult = rv;
return propValue;
}
nsresult nsPropertyTable::SetPropertyInternal(
nsPropertyOwner aObject, nsAtom* aPropertyName, void* aPropertyValue,
NSPropertyDtorFunc aPropDtorFunc, void* aPropDtorData, bool aTransfer) {
MOZ_ASSERT(aPropertyName && aObject, "unexpected null param");
PropertyList* propertyList = GetPropertyListFor(aPropertyName);
if (propertyList) {
// Make sure the dtor function and data and the transfer flag match
if (aPropDtorFunc != propertyList->mDtorFunc ||
aPropDtorData != propertyList->mDtorData ||
aTransfer != propertyList->mTransfer) {
NS_WARNING("Destructor/data mismatch while setting property");
return NS_ERROR_INVALID_ARG;
}
} else {
propertyList = new PropertyList(aPropertyName, aPropDtorFunc, aPropDtorData,
aTransfer);
propertyList->mNext = mPropertyList;
mPropertyList = propertyList;
}
// The current property value (if there is one) is replaced and the current
// value is destroyed
nsresult result = NS_OK;
propertyList->mObjectValueMap.WithEntryHandle(aObject, [&](auto&& entry) {
// If we already have an entry, call `mDtorFunc` on it.
if (entry) {
if (propertyList->mDtorFunc) {
propertyList->mDtorFunc(const_cast<void*>(entry.Entry()->GetKey()),
aPropertyName, entry.Entry()->GetData(),
propertyList->mDtorData);
}
result = NS_PROPTABLE_PROP_OVERWRITTEN;
}
entry.InsertOrUpdate(aPropertyValue);
});
return result;
}
nsresult nsPropertyTable::RemoveProperty(nsPropertyOwner aObject,
const nsAtom* aPropertyName) {
MOZ_ASSERT(aPropertyName && aObject, "unexpected null param");
PropertyList* propertyList = GetPropertyListFor(aPropertyName);
if (propertyList) {
if (propertyList->RemovePropertyFor(aObject)) {
return NS_OK;
}
}
return NS_PROPTABLE_PROP_NOT_THERE;
}
nsPropertyTable::PropertyList* nsPropertyTable::GetPropertyListFor(
const nsAtom* aPropertyName) const {
PropertyList* result;
for (result = mPropertyList; result; result = result->mNext) {
if (result->Equals(aPropertyName)) {
break;
}
}
return result;
}
//----------------------------------------------------------------------
nsPropertyTable::PropertyList::PropertyList(nsAtom* aName,
NSPropertyDtorFunc aDtorFunc,
void* aDtorData, bool aTransfer)
: mName(aName),
mDtorFunc(aDtorFunc),
mDtorData(aDtorData),
mTransfer(aTransfer),
mNext(nullptr) {}
nsPropertyTable::PropertyList::~PropertyList() = default;
void nsPropertyTable::PropertyList::Destroy() {
// Enumerate any remaining object/value pairs and destroy the value object.
if (mDtorFunc) {
for (const auto& entry : mObjectValueMap) {
mDtorFunc(const_cast<void*>(entry.GetKey()), mName, entry.GetData(),
mDtorData);
}
}
}
bool nsPropertyTable::PropertyList::RemovePropertyFor(nsPropertyOwner aObject) {
void* oldValue = nullptr;
if (mObjectValueMap.Remove(aObject, &oldValue)) {
if (mDtorFunc) {
mDtorFunc(const_cast<void*>(aObject.get()), mName, oldValue, mDtorData);
}
return false;
}
return true;
}
size_t nsPropertyTable::PropertyList::SizeOfIncludingThis(
mozilla::MallocSizeOf aMallocSizeOf) {
size_t n = aMallocSizeOf(this);
n += mObjectValueMap.ShallowSizeOfExcludingThis(aMallocSizeOf);
return n;
}
size_t nsPropertyTable::SizeOfExcludingThis(
mozilla::MallocSizeOf aMallocSizeOf) const {
size_t n = 0;
for (PropertyList* prop = mPropertyList; prop; prop = prop->mNext) {
n += prop->SizeOfIncludingThis(aMallocSizeOf);
}
return n;
}
size_t nsPropertyTable::SizeOfIncludingThis(
mozilla::MallocSizeOf aMallocSizeOf) const {
return aMallocSizeOf(this) + SizeOfExcludingThis(aMallocSizeOf);
}
/* static */
void nsPropertyTable::SupportsDtorFunc(void* aObject, nsAtom* aPropertyName,
void* aPropertyValue, void* aData) {
nsISupports* propertyValue = static_cast<nsISupports*>(aPropertyValue);
NS_IF_RELEASE(propertyValue);
}