gecko-dev/dom/svg/SVGElementFactory.cpp
2015-05-03 15:32:37 -04:00

146 lines
4.6 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 "SVGElementFactory.h"
#include "nsGkAtoms.h"
#include "nsIContent.h"
#include "mozilla/dom/NodeInfo.h"
#include "mozilla/dom/Element.h"
#include "mozilla/dom/FromParser.h"
using namespace mozilla;
using namespace mozilla::dom;
// Hash table that maps nsIAtom* SVG tags to an offset index
// within the array sContentCreatorCallbacks (offset by TABLE_VALUE_OFFSET)
static PLHashTable* sTagAtomTable = nullptr;
// We don't want to store 0 in the hash table as a return value of 0 from
// PL_HashTableLookupConst indicates that the value is not found
#define TABLE_VALUE_OFFSET 1
#define SVG_TAG(_tag, _classname) \
nsresult \
NS_NewSVG##_classname##Element(nsIContent** aResult, \
already_AddRefed<mozilla::dom::NodeInfo>&& aNodeInfo); \
\
static inline nsresult \
Create##_classname##Element(nsIContent** aResult, \
already_AddRefed<mozilla::dom::NodeInfo>&& aNodeInfo, \
FromParser aFromParser) \
{ \
return NS_NewSVG##_classname##Element(aResult, mozilla::Move(aNodeInfo)); \
}
#define SVG_FROM_PARSER_TAG(_tag, _classname) \
nsresult \
NS_NewSVG##_classname##Element(nsIContent** aResult, \
already_AddRefed<mozilla::dom::NodeInfo>&& aNodeInfo, \
FromParser aFromParser);
#include "SVGTagList.h"
#undef SVG_TAG
#undef SVG_FROM_PARSER_TAG
nsresult
NS_NewSVGElement(Element** aResult,
already_AddRefed<mozilla::dom::NodeInfo>&& aNodeInfo);
typedef nsresult
(*contentCreatorCallback)(nsIContent** aResult,
already_AddRefed<mozilla::dom::NodeInfo>&& aNodeInfo,
FromParser aFromParser);
static const contentCreatorCallback sContentCreatorCallbacks[] = {
#define SVG_TAG(_tag, _classname) Create##_classname##Element,
#define SVG_FROM_PARSER_TAG(_tag, _classname) NS_NewSVG##_classname##Element,
#include "SVGTagList.h"
#undef SVG_TAG
#undef SVG_FROM_PARSER_TAG
};
enum SVGTag {
#define SVG_TAG(_tag, _classname) eSVGTag_##_tag,
#define SVG_FROM_PARSER_TAG(_tag, _classname) eSVGTag_##_tag,
#include "SVGTagList.h"
#undef SVG_TAG
#undef SVG_FROM_PARSER_TAG
eSVGTag_Count
};
// nsIAtom* -> id hash
static PLHashNumber
SVGTagsHashCodeAtom(const void* key)
{
return NS_PTR_TO_INT32(key) >> 2;
}
void
SVGElementFactory::Init()
{
sTagAtomTable = PL_NewHashTable(64, SVGTagsHashCodeAtom,
PL_CompareValues, PL_CompareValues,
nullptr, nullptr);
#define SVG_TAG(_tag, _classname) \
PL_HashTableAdd(sTagAtomTable, nsGkAtoms::_tag,\
NS_INT32_TO_PTR(eSVGTag_##_tag + TABLE_VALUE_OFFSET));
#define SVG_FROM_PARSER_TAG(_tag, _classname) \
PL_HashTableAdd(sTagAtomTable, nsGkAtoms::_tag,\
NS_INT32_TO_PTR(eSVGTag_##_tag + TABLE_VALUE_OFFSET));
#include "SVGTagList.h"
#undef SVG_TAG
#undef SVG_FROM_PARSER_TAG
}
void
SVGElementFactory::Shutdown()
{
if (sTagAtomTable) {
PL_HashTableDestroy(sTagAtomTable);
sTagAtomTable = nullptr;
}
}
bool
SVGElementFactory::Exists(nsIAtom *aTag)
{
MOZ_ASSERT(sTagAtomTable, "no lookup table, needs SVGElementFactory::Init");
void* tag = PL_HashTableLookupConst(sTagAtomTable, aTag);
return tag != nullptr;
}
nsresult
NS_NewSVGElement(Element** aResult, already_AddRefed<mozilla::dom::NodeInfo>&& aNodeInfo,
FromParser aFromParser)
{
NS_ASSERTION(sTagAtomTable, "no lookup table, needs SVGElementFactory::Init");
nsRefPtr<mozilla::dom::NodeInfo> ni = aNodeInfo;
nsIAtom* name = ni->NameAtom();
NS_ASSERTION(ni->NamespaceEquals(kNameSpaceID_SVG),
"Trying to create SVG elements that aren't in the SVG namespace");
void* tag = PL_HashTableLookupConst(sTagAtomTable, name);
if (tag) {
int32_t index = NS_PTR_TO_INT32(tag) - TABLE_VALUE_OFFSET;
if (index < 0 || index >= eSVGTag_Count) {
NS_WARNING("About to index out of array bounds - crashing instead");
MOZ_CRASH();
}
contentCreatorCallback cb = sContentCreatorCallbacks[index];
nsCOMPtr<nsIContent> content;
nsresult rv = cb(getter_AddRefs(content), ni.forget(), aFromParser);
*aResult = content.forget().take()->AsElement();
return rv;
}
// if we don't know what to create, just create a standard svg element:
return NS_NewSVGElement(aResult, ni.forget());
}