gecko-dev/mfbt/tests/TestBloomFilter.cpp

143 строки
4.2 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 "mozilla/Assertions.h"
#include "mozilla/BloomFilter.h"
#include "mozilla/UniquePtr.h"
#include <stddef.h>
#include <stdio.h>
using mozilla::BitBloomFilter;
using mozilla::CountingBloomFilter;
class FilterChecker {
public:
explicit FilterChecker(uint32_t aHash) : mHash(aHash) {}
uint32_t hash() const { return mHash; }
private:
uint32_t mHash;
};
void testBitBloomFilter() {
const mozilla::UniquePtr filter =
mozilla::MakeUnique<BitBloomFilter<12, FilterChecker>>();
MOZ_RELEASE_ASSERT(filter);
FilterChecker one(1);
FilterChecker two(0x20000);
filter->add(&one);
MOZ_RELEASE_ASSERT(filter->mightContain(&one), "Filter should contain 'one'");
MOZ_RELEASE_ASSERT(!filter->mightContain(&two),
"Filter claims to contain 'two' when it should not");
// Test multiple addition
filter->add(&two);
MOZ_RELEASE_ASSERT(filter->mightContain(&two),
"Filter should contain 'two' after 'two' is added");
filter->add(&two);
MOZ_RELEASE_ASSERT(filter->mightContain(&two),
"Filter should contain 'two' after 'two' is added again");
filter->clear();
MOZ_RELEASE_ASSERT(!filter->mightContain(&one), "clear() failed to work");
MOZ_RELEASE_ASSERT(!filter->mightContain(&two), "clear() failed to work");
}
void testCountingBloomFilter() {
const mozilla::UniquePtr filter =
mozilla::MakeUnique<CountingBloomFilter<12, FilterChecker>>();
MOZ_RELEASE_ASSERT(filter);
FilterChecker one(1);
FilterChecker two(0x20000);
FilterChecker many(0x10000);
FilterChecker multiple(0x20001);
filter->add(&one);
MOZ_RELEASE_ASSERT(filter->mightContain(&one), "Filter should contain 'one'");
MOZ_RELEASE_ASSERT(!filter->mightContain(&multiple),
"Filter claims to contain 'multiple' when it should not");
MOZ_RELEASE_ASSERT(filter->mightContain(&many),
"Filter should contain 'many' (false positive)");
filter->add(&two);
MOZ_RELEASE_ASSERT(filter->mightContain(&multiple),
"Filter should contain 'multiple' (false positive)");
// Test basic removals
filter->remove(&two);
MOZ_RELEASE_ASSERT(
!filter->mightContain(&multiple),
"Filter claims to contain 'multiple' when it should not after two "
"was removed");
// Test multiple addition/removal
const size_t FILTER_SIZE = 255;
for (size_t i = 0; i < FILTER_SIZE - 1; ++i) {
filter->add(&two);
}
MOZ_RELEASE_ASSERT(
filter->mightContain(&multiple),
"Filter should contain 'multiple' after 'two' added lots of times "
"(false positive)");
for (size_t i = 0; i < FILTER_SIZE - 1; ++i) {
filter->remove(&two);
}
MOZ_RELEASE_ASSERT(
!filter->mightContain(&multiple),
"Filter claims to contain 'multiple' when it should not after two "
"was removed lots of times");
// Test overflowing the filter buckets
for (size_t i = 0; i < FILTER_SIZE + 1; ++i) {
filter->add(&two);
}
MOZ_RELEASE_ASSERT(
filter->mightContain(&multiple),
"Filter should contain 'multiple' after 'two' added lots more "
"times (false positive)");
for (size_t i = 0; i < FILTER_SIZE + 1; ++i) {
filter->remove(&two);
}
MOZ_RELEASE_ASSERT(
filter->mightContain(&multiple),
"Filter claims to not contain 'multiple' even though we should "
"have run out of space in the buckets (false positive)");
MOZ_RELEASE_ASSERT(
filter->mightContain(&two),
"Filter claims to not contain 'two' even though we should have "
"run out of space in the buckets (false positive)");
filter->remove(&one);
MOZ_RELEASE_ASSERT(
!filter->mightContain(&one),
"Filter should not contain 'one', because we didn't overflow its "
"bucket");
filter->clear();
MOZ_RELEASE_ASSERT(!filter->mightContain(&multiple),
"clear() failed to work");
}
int main() {
testBitBloomFilter();
testCountingBloomFilter();
return 0;
}