gecko-dev/toolkit/components/url-classifier/ChunkSet.h

97 строки
2.5 KiB
C++

//* -*- Mode: C++; tab-width: 8; 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 ChunkSet_h__
#define ChunkSet_h__
#include "Entries.h"
#include "nsString.h"
#include "nsTArray.h"
namespace mozilla {
namespace safebrowsing {
/**
* Store the chunk numbers as an array of ranges of uint32_t.
* We need chunk numbers in order to ask for incremental updates from the
* server.
*/
class ChunkSet {
public:
nsresult Serialize(nsACString& aStr);
nsresult Set(uint32_t aChunk);
bool Has(uint32_t chunk) const;
nsresult Merge(const ChunkSet& aOther);
uint32_t Length() const;
nsresult Remove(const ChunkSet& aOther);
void Clear();
nsresult Write(nsIOutputStream* aOut) const;
nsresult Read(nsIInputStream* aIn, uint32_t aNumElements);
ChunkSet InfallibleClone() const {
ChunkSet result;
if (!result.mRanges.Assign(mRanges, fallible)) {
MOZ_CRASH("Out of memory");
}
return result;
}
private:
class Range {
public:
Range(uint32_t aBegin, uint32_t aEnd) : mBegin(aBegin), mEnd(aEnd) {}
uint32_t Length() const;
nsresult Remove(const Range& aRange, ChunkSet& aRemainderSet) const;
bool FoldLeft(const Range& aRange);
bool operator==(const Range& rhs) const { return mBegin == rhs.mBegin; }
bool operator<(const Range& rhs) const { return mBegin < rhs.mBegin; }
uint32_t Begin() const { return mBegin; }
void Begin(const uint32_t aBegin) { mBegin = aBegin; }
uint32_t End() const { return mEnd; }
void End(const uint32_t aEnd) { mEnd = aEnd; }
bool Contains(const Range& aRange) const {
return mBegin <= aRange.mBegin && aRange.mEnd <= mEnd;
}
bool Precedes(const Range& aRange) const {
return mEnd + 1 == aRange.mBegin;
}
struct IntersectionComparator {
int operator()(const Range& aRange) const {
if (aRange.mBegin > mTarget.mEnd) {
return -1;
}
if (mTarget.mBegin > aRange.mEnd) {
return 1;
}
return 0;
}
explicit IntersectionComparator(const Range& aTarget)
: mTarget(aTarget) {}
const Range& mTarget;
};
private:
uint32_t mBegin;
uint32_t mEnd;
};
static const size_t IO_BUFFER_SIZE = 1024;
FallibleTArray<Range> mRanges;
bool HasSubrange(const Range& aSubrange) const;
};
} // namespace safebrowsing
} // namespace mozilla
#endif