mirror of
https://github.com/mozilla/gecko-dev.git
synced 2024-10-30 13:45:27 +00:00
100 lines
3.5 KiB
C++
100 lines
3.5 KiB
C++
/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
|
|
/* 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/. */
|
|
#ifndef nsContentIndexCache_h__
|
|
#define nsContentIndexCache_h__
|
|
|
|
#include "js/HashTable.h"
|
|
|
|
class nsIContent;
|
|
|
|
namespace mozilla {
|
|
namespace dom {
|
|
class Element;
|
|
} // namespace dom
|
|
} // namespace mozilla
|
|
|
|
/*
|
|
* A class that computes and caches the indices used for :nth-* pseudo-class
|
|
* matching.
|
|
*/
|
|
|
|
class nsNthIndexCache {
|
|
private:
|
|
typedef mozilla::dom::Element Element;
|
|
|
|
public:
|
|
/**
|
|
* Constructor and destructor out of line so that we don't try to
|
|
* instantiate the hashtable template all over the place.
|
|
*/
|
|
nsNthIndexCache();
|
|
~nsNthIndexCache();
|
|
|
|
// Returns a 1-based index of the child in its parent. If the child
|
|
// is not in its parent's child list (i.e., it is anonymous content),
|
|
// returns 0.
|
|
// If aCheckEdgeOnly is true, the function will return 1 if the result
|
|
// is 1, and something other than 1 (maybe or maybe not a valid
|
|
// result) otherwise.
|
|
// This must only be called on nodes which have a non-null parent.
|
|
int32_t GetNthIndex(Element* aChild, bool aIsOfType, bool aIsFromEnd,
|
|
bool aCheckEdgeOnly);
|
|
|
|
void Reset();
|
|
|
|
private:
|
|
/**
|
|
* Returns true if aSibling and aElement should be considered in the same
|
|
* list for nth-index purposes, taking aIsOfType into account.
|
|
*/
|
|
inline bool SiblingMatchesElement(nsIContent* aSibling, Element* aElement,
|
|
bool aIsOfType);
|
|
|
|
// This node's index for this cache.
|
|
// If -2, needs to be computed.
|
|
// If -1, needs to be computed but known not to be 1.
|
|
// If 0, the node is not at any index in its parent.
|
|
typedef int32_t CacheEntry;
|
|
|
|
class SystemAllocPolicy {
|
|
public:
|
|
void *malloc_(size_t bytes) { return ::malloc(bytes); }
|
|
void *calloc_(size_t bytes) { return ::calloc(bytes, 1); }
|
|
void *realloc_(void *p, size_t bytes) { return ::realloc(p, bytes); }
|
|
void free_(void *p) { ::free(p); }
|
|
void reportAllocOverflow() const {}
|
|
};
|
|
|
|
typedef js::HashMap<nsIContent*, CacheEntry, js::DefaultHasher<nsIContent*>,
|
|
SystemAllocPolicy> Cache;
|
|
|
|
/**
|
|
* Returns true if aResult has been set to the correct value for aChild and
|
|
* no more work needs to be done. Returns false otherwise.
|
|
*
|
|
* aResult is an inout parameter. The in value is the number of elements
|
|
* that are in the half-open range (aSibling, aChild] (so including aChild
|
|
* but not including aSibling) that match aChild. The out value is the
|
|
* correct index for aChild if this function returns true and the number of
|
|
* elements in the closed range [aSibling, aChild] that match aChild
|
|
* otherwise.
|
|
*/
|
|
inline bool IndexDeterminedFromPreviousSibling(nsIContent* aSibling,
|
|
Element* aChild,
|
|
bool aIsOfType,
|
|
bool aIsFromEnd,
|
|
const Cache& aCache,
|
|
int32_t& aResult);
|
|
|
|
// Caches of indices for :nth-child(), :nth-last-child(),
|
|
// :nth-of-type(), :nth-last-of-type(), keyed by Element*.
|
|
//
|
|
// The first subscript is 0 for -child and 1 for -of-type, the second
|
|
// subscript is 0 for nth- and 1 for nth-last-.
|
|
Cache mCaches[2][2];
|
|
};
|
|
|
|
#endif /* nsContentIndexCache_h__ */
|