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authorMatt A. Tobin <mattatobin@localhost.localdomain>2018-02-02 04:16:08 -0500
committerMatt A. Tobin <mattatobin@localhost.localdomain>2018-02-02 04:16:08 -0500
commit5f8de423f190bbb79a62f804151bc24824fa32d8 (patch)
tree10027f336435511475e392454359edea8e25895d /layout/style/nsCSSPropertyIDSet.h
parent49ee0794b5d912db1f95dce6eb52d781dc210db5 (diff)
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Add m-esr52 at 52.6.0
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diff --git a/layout/style/nsCSSPropertyIDSet.h b/layout/style/nsCSSPropertyIDSet.h
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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/. */
+
+/* bit vectors for sets of CSS properties */
+
+#ifndef nsCSSPropertyIDSet_h__
+#define nsCSSPropertyIDSet_h__
+
+#include "mozilla/ArrayUtils.h"
+#include "mozilla/PodOperations.h"
+
+#include "nsCSSPropertyID.h"
+#include <limits.h> // for CHAR_BIT
+
+/**
+ * nsCSSPropertyIDSet maintains a set of non-shorthand CSS properties. In
+ * other words, for each longhand CSS property we support, it has a bit
+ * for whether that property is in the set.
+ */
+class nsCSSPropertyIDSet {
+public:
+ nsCSSPropertyIDSet() { Empty(); }
+ // auto-generated copy-constructor OK
+
+ void AssertInSetRange(nsCSSPropertyID aProperty) const {
+ NS_ASSERTION(0 <= aProperty &&
+ aProperty < eCSSProperty_COUNT_no_shorthands,
+ "out of bounds");
+ }
+
+ // Conversion of aProperty to |size_t| after AssertInSetRange
+ // lets the compiler generate significantly tighter code.
+
+ void AddProperty(nsCSSPropertyID aProperty) {
+ AssertInSetRange(aProperty);
+ size_t p = aProperty;
+ mProperties[p / kBitsInChunk] |=
+ property_set_type(1) << (p % kBitsInChunk);
+ }
+
+ void RemoveProperty(nsCSSPropertyID aProperty) {
+ AssertInSetRange(aProperty);
+ size_t p = aProperty;
+ mProperties[p / kBitsInChunk] &=
+ ~(property_set_type(1) << (p % kBitsInChunk));
+ }
+
+ bool HasProperty(nsCSSPropertyID aProperty) const {
+ AssertInSetRange(aProperty);
+ size_t p = aProperty;
+ return (mProperties[p / kBitsInChunk] &
+ (property_set_type(1) << (p % kBitsInChunk))) != 0;
+ }
+
+ void Empty() {
+ memset(mProperties, 0, sizeof(mProperties));
+ }
+
+ void AssertIsEmpty(const char* aText) const {
+ for (size_t i = 0; i < mozilla::ArrayLength(mProperties); ++i) {
+ NS_ASSERTION(mProperties[i] == 0, aText);
+ }
+ }
+
+ bool Equals(const nsCSSPropertyIDSet& aOther) const {
+ return mozilla::PodEqual(mProperties, aOther.mProperties);
+ }
+
+ // Return a new nsCSSPropertyIDSet which is the inverse of this set.
+ nsCSSPropertyIDSet Invert() const {
+ nsCSSPropertyIDSet result;
+ for (size_t i = 0; i < mozilla::ArrayLength(mProperties); ++i) {
+ result.mProperties[i] = ~mProperties[i];
+ }
+ return result;
+ }
+
+private:
+ typedef unsigned long property_set_type;
+public:
+ // number of bits in |property_set_type|.
+ static const size_t kBitsInChunk = sizeof(property_set_type)*CHAR_BIT;
+ // number of |property_set_type|s in the set
+ static const size_t kChunkCount =
+ (eCSSProperty_COUNT_no_shorthands + kBitsInChunk - 1) / kBitsInChunk;
+
+ /*
+ * For fast enumeration of all the bits that are set, callers can
+ * check each chunk against zero (since in normal cases few bits are
+ * likely to be set).
+ */
+ bool HasPropertyInChunk(size_t aChunk) const {
+ return mProperties[aChunk] != 0;
+ }
+ bool HasPropertyAt(size_t aChunk, size_t aBit) const {
+ return (mProperties[aChunk] & (property_set_type(1) << aBit)) != 0;
+ }
+ static nsCSSPropertyID CSSPropertyAt(size_t aChunk, size_t aBit) {
+ return nsCSSPropertyID(aChunk * kBitsInChunk + aBit);
+ }
+
+private:
+ property_set_type mProperties[kChunkCount];
+};
+
+#endif /* !defined(nsCSSPropertyIDSet_h__) */