tequilaOS/platform_system_core
2
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity

resolved conflicts for 70808827 to stage-aosp-master

Browse source 
Change-Id: I5e5030a20f2be3bd15b9fec8192dd22ec5a34d87
This commit is contained in:
Sergio Giro 2015-10-01 18:54:33 +01:00
commit 5cf2d5c9cc
5 changed files with 0 additions and 1329 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

395
include/utils/BasicHashtable.h
View file

@ -1,395 +0,0 @@
/*
* Copyright (C) 2011 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#ifndef ANDROID_BASIC_HASHTABLE_H
#define ANDROID_BASIC_HASHTABLE_H
#include <stdint.h>
#include <sys/types.h>
#include <utils/TypeHelpers.h>
namespace android {
/* Implementation type. Nothing to see here. */
class BasicHashtableImpl {
protected:
struct Bucket {
// The collision flag indicates that the bucket is part of a collision chain
// such that at least two entries both hash to this bucket. When true, we
// may need to seek further along the chain to find the entry.
static const uint32_t COLLISION = 0x80000000UL;
// The present flag indicates that the bucket contains an initialized entry value.
static const uint32_t PRESENT = 0x40000000UL;
// Mask for 30 bits worth of the hash code that are stored within the bucket to
// speed up lookups and rehashing by eliminating the need to recalculate the
// hash code of the entry's key.
static const uint32_t HASH_MASK = 0x3fffffffUL;
// Combined value that stores the collision and present flags as well as
// a 30 bit hash code.
uint32_t cookie;
// Storage for the entry begins here.
char entry[0];
};
BasicHashtableImpl(size_t entrySize, bool hasTrivialDestructor,
size_t minimumInitialCapacity, float loadFactor);
BasicHashtableImpl(const BasicHashtableImpl& other);
virtual ~BasicHashtableImpl();
void dispose();
void edit();
void setTo(const BasicHashtableImpl& other);
void clear();
ssize_t next(ssize_t index) const;
ssize_t find(ssize_t index, hash_t hash, const void* __restrict__ key) const;
size_t add(hash_t hash, const void* __restrict__ entry);
void removeAt(size_t index);
void rehash(size_t minimumCapacity, float loadFactor);
const size_t mBucketSize; // number of bytes per bucket including the entry
const bool mHasTrivialDestructor; // true if the entry type does not require destruction
size_t mCapacity; // number of buckets that can be filled before exceeding load factor
float mLoadFactor; // load factor
size_t mSize; // number of elements actually in the table
size_t mFilledBuckets; // number of buckets for which collision or present is true
size_t mBucketCount; // number of slots in the mBuckets array
void* mBuckets; // array of buckets, as a SharedBuffer
inline const Bucket& bucketAt(const void* __restrict__ buckets, size_t index) const {
return *reinterpret_cast<const Bucket*>(
static_cast<const uint8_t*>(buckets) + index * mBucketSize);
}
inline Bucket& bucketAt(void* __restrict__ buckets, size_t index) const {
return *reinterpret_cast<Bucket*>(static_cast<uint8_t*>(buckets) + index * mBucketSize);
}
virtual bool compareBucketKey(const Bucket& bucket, const void* __restrict__ key) const = 0;
virtual void initializeBucketEntry(Bucket& bucket, const void* __restrict__ entry) const = 0;
virtual void destroyBucketEntry(Bucket& bucket) const = 0;
private:
void clone();
// Allocates a bucket array as a SharedBuffer.
void* allocateBuckets(size_t count) const;
// Releases a bucket array's associated SharedBuffer.
void releaseBuckets(void* __restrict__ buckets, size_t count) const;
// Destroys the contents of buckets (invokes destroyBucketEntry for each
// populated bucket if needed).
void destroyBuckets(void* __restrict__ buckets, size_t count) const;
// Copies the content of buckets (copies the cookie and invokes copyBucketEntry
// for each populated bucket if needed).
void copyBuckets(const void* __restrict__ fromBuckets,
void* __restrict__ toBuckets, size_t count) const;
// Determines the appropriate size of a bucket array to store a certain minimum
// number of entries and returns its effective capacity.
static void determineCapacity(size_t minimumCapacity, float loadFactor,
size_t* __restrict__ outBucketCount, size_t* __restrict__ outCapacity);
// Trim a hash code to 30 bits to match what we store in the bucket's cookie.
inline static hash_t trimHash(hash_t hash) {
return (hash & Bucket::HASH_MASK) ^ (hash >> 30);
}
// Returns the index of the first bucket that is in the collision chain
// for the specified hash code, given the total number of buckets.
// (Primary hash)
inline static size_t chainStart(hash_t hash, size_t count) {
return hash % count;
}
// Returns the increment to add to a bucket index to seek to the next bucket
// in the collision chain for the specified hash code, given the total number of buckets.
// (Secondary hash)
inline static size_t chainIncrement(hash_t hash, size_t count) {
return ((hash >> 7) | (hash << 25)) % (count - 1) + 1;
}
// Returns the index of the next bucket that is in the collision chain
// that is defined by the specified increment, given the total number of buckets.
inline static size_t chainSeek(size_t index, size_t increment, size_t count) {
return (index + increment) % count;
}
};
/*
* A BasicHashtable stores entries that are indexed by hash code in place
* within an array. The basic operations are finding entries by key,
* adding new entries and removing existing entries.
*
* This class provides a very limited set of operations with simple semantics.
* It is intended to be used as a building block to construct more complex
* and interesting data structures such as HashMap. Think very hard before
* adding anything extra to BasicHashtable, it probably belongs at a
* higher level of abstraction.
*
* TKey: The key type.
* TEntry: The entry type which is what is actually stored in the array.
*
* TKey must support the following contract:
* bool operator==(const TKey& other) const; // return true if equal
* bool operator!=(const TKey& other) const; // return true if unequal
*
* TEntry must support the following contract:
* const TKey& getKey() const; // get the key from the entry
*
* This class supports storing entries with duplicate keys. Of course, it can't
* tell them apart during removal so only the first entry will be removed.
* We do this because it means that operations like add() can't fail.
*/
template <typename TKey, typename TEntry>
class BasicHashtable : private BasicHashtableImpl {
public:
/* Creates a hashtable with the specified minimum initial capacity.
* The underlying array will be created when the first entry is added.
*
* minimumInitialCapacity: The minimum initial capacity for the hashtable.
* Default is 0.
* loadFactor: The desired load factor for the hashtable, between 0 and 1.
* Default is 0.75.
*/
BasicHashtable(size_t minimumInitialCapacity = 0, float loadFactor = 0.75f);
/* Copies a hashtable.
* The underlying storage is shared copy-on-write.
*/
BasicHashtable(const BasicHashtable& other);
/* Clears and destroys the hashtable.
*/
virtual ~BasicHashtable();
/* Making this hashtable a copy of the other hashtable.
* The underlying storage is shared copy-on-write.
*
* other: The hashtable to copy.
*/
inline BasicHashtable<TKey, TEntry>& operator =(const BasicHashtable<TKey, TEntry> & other) {
setTo(other);
return *this;
}
/* Returns the number of entries in the hashtable.
*/
inline size_t size() const {
return mSize;
}
/* Returns the capacity of the hashtable, which is the number of elements that can
* added to the hashtable without requiring it to be grown.
*/
inline size_t capacity() const {
return mCapacity;
}
/* Returns the number of buckets that the hashtable has, which is the size of its
* underlying array.
*/
inline size_t bucketCount() const {
return mBucketCount;
}
/* Returns the load factor of the hashtable. */
inline float loadFactor() const {
return mLoadFactor;
};
/* Returns a const reference to the entry at the specified index.
*
* index: The index of the entry to retrieve. Must be a valid index within
* the bounds of the hashtable.
*/
inline const TEntry& entryAt(size_t index) const {
return entryFor(bucketAt(mBuckets, index));
}
/* Returns a non-const reference to the entry at the specified index.
*
* index: The index of the entry to edit. Must be a valid index within
* the bounds of the hashtable.
*/
inline TEntry& editEntryAt(size_t index) {
edit();
return entryFor(bucketAt(mBuckets, index));
}
/* Clears the hashtable.
* All entries in the hashtable are destroyed immediately.
* If you need to do something special with the entries in the hashtable then iterate
* over them and do what you need before clearing the hashtable.
*/
inline void clear() {
BasicHashtableImpl::clear();
}
/* Returns the index of the next entry in the hashtable given the index of a previous entry.
* If the given index is -1, then returns the index of the first entry in the hashtable,
* if there is one, or -1 otherwise.
* If the given index is not -1, then returns the index of the next entry in the hashtable,
* in strictly increasing order, or -1 if there are none left.
*
* index: The index of the previous entry that was iterated, or -1 to begin
* iteration at the beginning of the hashtable.
*/
inline ssize_t next(ssize_t index) const {
return BasicHashtableImpl::next(index);
}
/* Finds the index of an entry with the specified key.
* If the given index is -1, then returns the index of the first matching entry,
* otherwise returns the index of the next matching entry.
* If the hashtable contains multiple entries with keys that match the requested
* key, then the sequence of entries returned is arbitrary.
* Returns -1 if no entry was found.
*
* index: The index of the previous entry with the specified key, or -1 to
* find the first matching entry.
* hash: The hashcode of the key.
* key: The key.
*/
inline ssize_t find(ssize_t index, hash_t hash, const TKey& key) const {
return BasicHashtableImpl::find(index, hash, &key);
}
/* Adds the entry to the hashtable.
* Returns the index of the newly added entry.
* If an entry with the same key already exists, then a duplicate entry is added.
* If the entry will not fit, then the hashtable's capacity is increased and
* its contents are rehashed. See rehash().
*
* hash: The hashcode of the key.
* entry: The entry to add.
*/
inline size_t add(hash_t hash, const TEntry& entry) {
return BasicHashtableImpl::add(hash, &entry);
}
/* Removes the entry with the specified index from the hashtable.
* The entry is destroyed immediately.
* The index must be valid.
*
* The hashtable is not compacted after an item is removed, so it is legal
* to continue iterating over the hashtable using next() or find().
*
* index: The index of the entry to remove. Must be a valid index within the
* bounds of the hashtable, and it must refer to an existing entry.
*/
inline void removeAt(size_t index) {
BasicHashtableImpl::removeAt(index);
}
/* Rehashes the contents of the hashtable.
* Grows the hashtable to at least the specified minimum capacity or the
* current number of elements, whichever is larger.
*
* Rehashing causes all entries to be copied and the entry indices may change.
* Although the hash codes are cached by the hashtable, rehashing can be an
* expensive operation and should be avoided unless the hashtable's size
* needs to be changed.
*
* Rehashing is the only way to change the capacity or load factor of the
* hashtable once it has been created. It can be used to compact the
* hashtable by choosing a minimum capacity that is smaller than the current
* capacity (such as 0).
*
* minimumCapacity: The desired minimum capacity after rehashing.
* loadFactor: The desired load factor after rehashing.
*/
inline void rehash(size_t minimumCapacity, float loadFactor) {
BasicHashtableImpl::rehash(minimumCapacity, loadFactor);
}
/* Determines whether there is room to add another entry without rehashing.
* When this returns true, a subsequent add() operation is guaranteed to
* complete without performing a rehash.
*/
inline bool hasMoreRoom() const {
return mCapacity > mFilledBuckets;
}
protected:
static inline const TEntry& entryFor(const Bucket& bucket) {
return reinterpret_cast<const TEntry&>(bucket.entry);
}
static inline TEntry& entryFor(Bucket& bucket) {
return reinterpret_cast<TEntry&>(bucket.entry);
}
virtual bool compareBucketKey(const Bucket& bucket, const void* __restrict__ key) const;
virtual void initializeBucketEntry(Bucket& bucket, const void* __restrict__ entry) const;
virtual void destroyBucketEntry(Bucket& bucket) const;
private:
// For dumping the raw contents of a hashtable during testing.
friend class BasicHashtableTest;
inline uint32_t cookieAt(size_t index) const {
return bucketAt(mBuckets, index).cookie;
}
};
template <typename TKey, typename TEntry>
BasicHashtable<TKey, TEntry>::BasicHashtable(size_t minimumInitialCapacity, float loadFactor) :
BasicHashtableImpl(sizeof(TEntry), traits<TEntry>::has_trivial_dtor,
minimumInitialCapacity, loadFactor) {
}
template <typename TKey, typename TEntry>
BasicHashtable<TKey, TEntry>::BasicHashtable(const BasicHashtable<TKey, TEntry>& other) :
BasicHashtableImpl(other) {
}
template <typename TKey, typename TEntry>
BasicHashtable<TKey, TEntry>::~BasicHashtable() {
dispose();
}
template <typename TKey, typename TEntry>
bool BasicHashtable<TKey, TEntry>::compareBucketKey(const Bucket& bucket,
const void* __restrict__ key) const {
return entryFor(bucket).getKey() == *static_cast<const TKey*>(key);
}
template <typename TKey, typename TEntry>
void BasicHashtable<TKey, TEntry>::initializeBucketEntry(Bucket& bucket,
const void* __restrict__ entry) const {
if (!traits<TEntry>::has_trivial_copy) {
new (&entryFor(bucket)) TEntry(*(static_cast<const TEntry*>(entry)));
} else {
memcpy(&entryFor(bucket), entry, sizeof(TEntry));
}
}
template <typename TKey, typename TEntry>
void BasicHashtable<TKey, TEntry>::destroyBucketEntry(Bucket& bucket) const {
if (!traits<TEntry>::has_trivial_dtor) {
entryFor(bucket).~TEntry();
}
}
}; // namespace android
#endif // ANDROID_BASIC_HASHTABLE_H

1
libutils/Android.mk
View file

@ -15,7 +15,6 @@
LOCAL_PATH:= $(call my-dir)
commonSources:= \
BasicHashtable.cpp \
CallStack.cpp \
FileMap.cpp \
JenkinsHash.cpp \

350
libutils/BasicHashtable.cpp
View file

@ -1,350 +0,0 @@
/*
* Copyright (C) 2011 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#define LOG_TAG "BasicHashtable"
#include <math.h>
#include <utils/Log.h>
#include <utils/BasicHashtable.h>
#include <utils/misc.h>
#include "SharedBuffer.h"
namespace android {
BasicHashtableImpl::BasicHashtableImpl(size_t entrySize, bool hasTrivialDestructor,
size_t minimumInitialCapacity, float loadFactor) :
mBucketSize(entrySize + sizeof(Bucket)), mHasTrivialDestructor(hasTrivialDestructor),
mLoadFactor(loadFactor), mSize(0),
mFilledBuckets(0), mBuckets(NULL) {
determineCapacity(minimumInitialCapacity, mLoadFactor, &mBucketCount, &mCapacity);
}
BasicHashtableImpl::BasicHashtableImpl(const BasicHashtableImpl& other) :
mBucketSize(other.mBucketSize), mHasTrivialDestructor(other.mHasTrivialDestructor),
mCapacity(other.mCapacity), mLoadFactor(other.mLoadFactor),
mSize(other.mSize), mFilledBuckets(other.mFilledBuckets),
mBucketCount(other.mBucketCount), mBuckets(other.mBuckets) {
if (mBuckets) {
SharedBuffer::bufferFromData(mBuckets)->acquire();
}
}
BasicHashtableImpl::~BasicHashtableImpl()
{
}
void BasicHashtableImpl::edit() {
if (mBuckets && !SharedBuffer::bufferFromData(mBuckets)->onlyOwner()) {
clone();
}
}
void BasicHashtableImpl::dispose() {
if (mBuckets) {
releaseBuckets(mBuckets, mBucketCount);
}
}
void BasicHashtableImpl::clone() {
if (mBuckets) {
void* newBuckets = allocateBuckets(mBucketCount);
copyBuckets(mBuckets, newBuckets, mBucketCount);
releaseBuckets(mBuckets, mBucketCount);
mBuckets = newBuckets;
}
}
void BasicHashtableImpl::setTo(const BasicHashtableImpl& other) {
if (mBuckets) {
releaseBuckets(mBuckets, mBucketCount);
}
mCapacity = other.mCapacity;
mLoadFactor = other.mLoadFactor;
mSize = other.mSize;
mFilledBuckets = other.mFilledBuckets;
mBucketCount = other.mBucketCount;
mBuckets = other.mBuckets;
if (mBuckets) {
SharedBuffer::bufferFromData(mBuckets)->acquire();
}
}
void BasicHashtableImpl::clear() {
if (mBuckets) {
if (mFilledBuckets) {
SharedBuffer* sb = SharedBuffer::bufferFromData(mBuckets);
if (sb->onlyOwner()) {
destroyBuckets(mBuckets, mBucketCount);
for (size_t i = 0; i < mBucketCount; i++) {
Bucket& bucket = bucketAt(mBuckets, i);
bucket.cookie = 0;
}
} else {
releaseBuckets(mBuckets, mBucketCount);
mBuckets = NULL;
}
mFilledBuckets = 0;
}
mSize = 0;
}
}
ssize_t BasicHashtableImpl::next(ssize_t index) const {
if (mSize) {
while (size_t(++index) < mBucketCount) {
const Bucket& bucket = bucketAt(mBuckets, index);
if (bucket.cookie & Bucket::PRESENT) {
return index;
}
}
}
return -1;
}
ssize_t BasicHashtableImpl::find(ssize_t index, hash_t hash,
const void* __restrict__ key) const {
if (!mSize) {
return -1;
}
hash = trimHash(hash);
if (index < 0) {
index = chainStart(hash, mBucketCount);
const Bucket& bucket = bucketAt(mBuckets, size_t(index));
if (bucket.cookie & Bucket::PRESENT) {
if (compareBucketKey(bucket, key)) {
return index;
}
} else {
if (!(bucket.cookie & Bucket::COLLISION)) {
return -1;
}
}
}
size_t inc = chainIncrement(hash, mBucketCount);
for (;;) {
index = chainSeek(index, inc, mBucketCount);
const Bucket& bucket = bucketAt(mBuckets, size_t(index));
if (bucket.cookie & Bucket::PRESENT) {
if ((bucket.cookie & Bucket::HASH_MASK) == hash
&& compareBucketKey(bucket, key)) {
return index;
}
}
if (!(bucket.cookie & Bucket::COLLISION)) {
return -1;
}
}
}
size_t BasicHashtableImpl::add(hash_t hash, const void* entry) {
if (!mBuckets) {
mBuckets = allocateBuckets(mBucketCount);
} else {
edit();
}
hash = trimHash(hash);
for (;;) {
size_t index = chainStart(hash, mBucketCount);
Bucket* bucket = &bucketAt(mBuckets, size_t(index));
if (bucket->cookie & Bucket::PRESENT) {
size_t inc = chainIncrement(hash, mBucketCount);
do {
bucket->cookie |= Bucket::COLLISION;
index = chainSeek(index, inc, mBucketCount);
bucket = &bucketAt(mBuckets, size_t(index));
} while (bucket->cookie & Bucket::PRESENT);
}
uint32_t collision = bucket->cookie & Bucket::COLLISION;
if (!collision) {
if (mFilledBuckets >= mCapacity) {
rehash(mCapacity * 2, mLoadFactor);
continue;
}
mFilledBuckets += 1;
}
bucket->cookie = collision | Bucket::PRESENT | hash;
mSize += 1;
initializeBucketEntry(*bucket, entry);
return index;
}
}
void BasicHashtableImpl::removeAt(size_t index) {
edit();
Bucket& bucket = bucketAt(mBuckets, index);
bucket.cookie &= ~Bucket::PRESENT;
if (!(bucket.cookie & Bucket::COLLISION)) {
mFilledBuckets -= 1;
}
mSize -= 1;
if (!mHasTrivialDestructor) {
destroyBucketEntry(bucket);
}
}
void BasicHashtableImpl::rehash(size_t minimumCapacity, float loadFactor) {
if (minimumCapacity < mSize) {
minimumCapacity = mSize;
}
size_t newBucketCount, newCapacity;
determineCapacity(minimumCapacity, loadFactor, &newBucketCount, &newCapacity);
if (newBucketCount != mBucketCount || newCapacity != mCapacity) {
if (mBuckets) {
void* newBuckets;
if (mSize) {
newBuckets = allocateBuckets(newBucketCount);
for (size_t i = 0; i < mBucketCount; i++) {
const Bucket& fromBucket = bucketAt(mBuckets, i);
if (fromBucket.cookie & Bucket::PRESENT) {
hash_t hash = fromBucket.cookie & Bucket::HASH_MASK;
size_t index = chainStart(hash, newBucketCount);
Bucket* toBucket = &bucketAt(newBuckets, size_t(index));
if (toBucket->cookie & Bucket::PRESENT) {
size_t inc = chainIncrement(hash, newBucketCount);
do {
toBucket->cookie |= Bucket::COLLISION;
index = chainSeek(index, inc, newBucketCount);
toBucket = &bucketAt(newBuckets, size_t(index));
} while (toBucket->cookie & Bucket::PRESENT);
}
toBucket->cookie = Bucket::PRESENT | hash;
initializeBucketEntry(*toBucket, fromBucket.entry);
}
}
} else {
newBuckets = NULL;
}
releaseBuckets(mBuckets, mBucketCount);
mBuckets = newBuckets;
mFilledBuckets = mSize;
}
mBucketCount = newBucketCount;
mCapacity = newCapacity;
}
mLoadFactor = loadFactor;
}
void* BasicHashtableImpl::allocateBuckets(size_t count) const {
size_t bytes = count * mBucketSize;
SharedBuffer* sb = SharedBuffer::alloc(bytes);
LOG_ALWAYS_FATAL_IF(!sb, "Could not allocate %u bytes for hashtable with %u buckets.",
uint32_t(bytes), uint32_t(count));
void* buckets = sb->data();
for (size_t i = 0; i < count; i++) {
Bucket& bucket = bucketAt(buckets, i);
bucket.cookie = 0;
}
return buckets;
}
void BasicHashtableImpl::releaseBuckets(void* __restrict__ buckets, size_t count) const {
SharedBuffer* sb = SharedBuffer::bufferFromData(buckets);
if (sb->release(SharedBuffer::eKeepStorage) == 1) {
destroyBuckets(buckets, count);
SharedBuffer::dealloc(sb);
}
}
void BasicHashtableImpl::destroyBuckets(void* __restrict__ buckets, size_t count) const {
if (!mHasTrivialDestructor) {
for (size_t i = 0; i < count; i++) {
Bucket& bucket = bucketAt(buckets, i);
if (bucket.cookie & Bucket::PRESENT) {
destroyBucketEntry(bucket);
}
}
}
}
void BasicHashtableImpl::copyBuckets(const void* __restrict__ fromBuckets,
void* __restrict__ toBuckets, size_t count) const {
for (size_t i = 0; i < count; i++) {
const Bucket& fromBucket = bucketAt(fromBuckets, i);
Bucket& toBucket = bucketAt(toBuckets, i);
toBucket.cookie = fromBucket.cookie;
if (fromBucket.cookie & Bucket::PRESENT) {
initializeBucketEntry(toBucket, fromBucket.entry);
}
}
}
// Table of 31-bit primes where each prime is no less than twice as large
// as the previous one. Generated by "primes.py".
static size_t PRIMES[] = {
5,
11,
23,
47,
97,
197,
397,
797,
1597,
3203,
6421,
12853,
25717,
51437,
102877,
205759,
411527,
823117,
1646237,
3292489,
6584983,
13169977,
26339969,
52679969,
105359939,
210719881,
421439783,
842879579,
1685759167,
0,
};
void BasicHashtableImpl::determineCapacity(size_t minimumCapacity, float loadFactor,
size_t* __restrict__ outBucketCount, size_t* __restrict__ outCapacity) {
LOG_ALWAYS_FATAL_IF(loadFactor <= 0.0f || loadFactor > 1.0f,
"Invalid load factor %0.3f. Must be in the range (0, 1].", loadFactor);
size_t count = ceilf(minimumCapacity / loadFactor) + 1;
size_t i = 0;
while (count > PRIMES[i] && i < NELEM(PRIMES)) {
i++;
}
count = PRIMES[i];
LOG_ALWAYS_FATAL_IF(!count, "Could not determine required number of buckets for "
"hashtable with minimum capacity %u and load factor %0.3f.",
uint32_t(minimumCapacity), loadFactor);
*outBucketCount = count;
*outCapacity = ceilf((count - 1) * loadFactor);
}
}; // namespace android

1
libutils/tests/Android.mk
View file

@ -22,7 +22,6 @@ include $(CLEAR_VARS)
LOCAL_MODULE := libutils_tests
LOCAL_SRC_FILES := \
BasicHashtable_test.cpp \
BlobCache_test.cpp \
BitSet_test.cpp \
Looper_test.cpp \

582
libutils/tests/BasicHashtable_test.cpp
View file

@ -1,582 +0,0 @@
/*
* Copyright (C) 2011 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#define LOG_TAG "BasicHashtable_test"
#include <utils/BasicHashtable.h>
#include <cutils/log.h>
#include <gtest/gtest.h>
#include <unistd.h>
namespace {
typedef int SimpleKey;
typedef int SimpleValue;
typedef android::key_value_pair_t<SimpleKey, SimpleValue> SimpleEntry;
typedef android::BasicHashtable<SimpleKey, SimpleEntry> SimpleHashtable;
struct ComplexKey {
int k;
explicit ComplexKey(int k) : k(k) {
instanceCount += 1;
}
ComplexKey(const ComplexKey& other) : k(other.k) {
instanceCount += 1;
}
~ComplexKey() {
instanceCount -= 1;
}
bool operator ==(const ComplexKey& other) const {
return k == other.k;
}
bool operator !=(const ComplexKey& other) const {
return k != other.k;
}
static ssize_t instanceCount;
};
ssize_t ComplexKey::instanceCount = 0;
struct ComplexValue {
int v;
explicit ComplexValue(int v) : v(v) {
instanceCount += 1;
}
ComplexValue(const ComplexValue& other) : v(other.v) {
instanceCount += 1;
}
~ComplexValue() {
instanceCount -= 1;
}
static ssize_t instanceCount;
};
ssize_t ComplexValue::instanceCount = 0;
} // namespace
namespace android {
typedef key_value_pair_t<ComplexKey, ComplexValue> ComplexEntry;
typedef BasicHashtable<ComplexKey, ComplexEntry> ComplexHashtable;
template<> inline hash_t hash_type(const ComplexKey& value) {
return hash_type(value.k);
}
class BasicHashtableTest : public testing::Test {
protected:
virtual void SetUp() {
ComplexKey::instanceCount = 0;
ComplexValue::instanceCount = 0;
}
virtual void TearDown() {
ASSERT_NO_FATAL_FAILURE(assertInstanceCount(0, 0));
}
void assertInstanceCount(ssize_t keys, ssize_t values) {
if (keys != ComplexKey::instanceCount || values != ComplexValue::instanceCount) {
FAIL() << "Expected " << keys << " keys and " << values << " values "
"but there were actually " << ComplexKey::instanceCount << " keys and "
<< ComplexValue::instanceCount << " values";
}
}
public:
template <typename TKey, typename TEntry>
static void cookieAt(const BasicHashtable<TKey, TEntry>& h, size_t index,
bool* collision, bool* present, hash_t* hash) {
uint32_t cookie = h.cookieAt(index);
*collision = cookie & BasicHashtable<TKey, TEntry>::Bucket::COLLISION;
*present = cookie & BasicHashtable<TKey, TEntry>::Bucket::PRESENT;
*hash = cookie & BasicHashtable<TKey, TEntry>::Bucket::HASH_MASK;
}
template <typename TKey, typename TEntry>
static const void* getBuckets(const BasicHashtable<TKey, TEntry>& h) {
return h.mBuckets;
}
};
template <typename TKey, typename TValue>
static size_t add(BasicHashtable<TKey, key_value_pair_t<TKey, TValue> >& h,
const TKey& key, const TValue& value) {
return h.add(hash_type(key), key_value_pair_t<TKey, TValue>(key, value));
}
template <typename TKey, typename TValue>
static ssize_t find(BasicHashtable<TKey, key_value_pair_t<TKey, TValue> >& h,
ssize_t index, const TKey& key) {
return h.find(index, hash_type(key), key);
}
template <typename TKey, typename TValue>
static bool remove(BasicHashtable<TKey, key_value_pair_t<TKey, TValue> >& h,
const TKey& key) {
ssize_t index = find(h, -1, key);
if (index >= 0) {
h.removeAt(index);
return true;
}
return false;
}
template <typename TEntry>
static void getKeyValue(const TEntry& entry, int* key, int* value);
template <> void getKeyValue(const SimpleEntry& entry, int* key, int* value) {
*key = entry.key;
*value = entry.value;
}
template <> void getKeyValue(const ComplexEntry& entry, int* key, int* value) {
*key = entry.key.k;
*value = entry.value.v;
}
template <typename TKey, typename TValue>
static void dump(BasicHashtable<TKey, key_value_pair_t<TKey, TValue> >& h) {
ALOGD("hashtable %p, size=%u, capacity=%u, bucketCount=%u",
&h, h.size(), h.capacity(), h.bucketCount());
for (size_t i = 0; i < h.bucketCount(); i++) {
bool collision, present;
hash_t hash;
BasicHashtableTest::cookieAt(h, i, &collision, &present, &hash);
if (present) {
int key, value;
getKeyValue(h.entryAt(i), &key, &value);
ALOGD(" [%3u] = collision=%d, present=%d, hash=0x%08x, key=%3d, value=%3d, "
"hash_type(key)=0x%08x",
i, collision, present, hash, key, value, hash_type(key));
} else {
ALOGD(" [%3u] = collision=%d, present=%d",
i, collision, present);
}
}
}
TEST_F(BasicHashtableTest, DefaultConstructor_WithDefaultProperties) {
SimpleHashtable h;
EXPECT_EQ(0U, h.size());
EXPECT_EQ(3U, h.capacity());
EXPECT_EQ(5U, h.bucketCount());
EXPECT_EQ(0.75f, h.loadFactor());
}
TEST_F(BasicHashtableTest, Constructor_WithNonUnityLoadFactor) {
SimpleHashtable h(52, 0.8f);
EXPECT_EQ(0U, h.size());
EXPECT_EQ(77U, h.capacity());
EXPECT_EQ(97U, h.bucketCount());
EXPECT_EQ(0.8f, h.loadFactor());
}
TEST_F(BasicHashtableTest, Constructor_WithUnityLoadFactorAndExactCapacity) {
SimpleHashtable h(46, 1.0f);
EXPECT_EQ(0U, h.size());
EXPECT_EQ(46U, h.capacity()); // must be one less than bucketCount because loadFactor == 1.0f
EXPECT_EQ(47U, h.bucketCount());
EXPECT_EQ(1.0f, h.loadFactor());
}
TEST_F(BasicHashtableTest, Constructor_WithUnityLoadFactorAndInexactCapacity) {
SimpleHashtable h(42, 1.0f);
EXPECT_EQ(0U, h.size());
EXPECT_EQ(46U, h.capacity()); // must be one less than bucketCount because loadFactor == 1.0f
EXPECT_EQ(47U, h.bucketCount());
EXPECT_EQ(1.0f, h.loadFactor());
}
TEST_F(BasicHashtableTest, FindAddFindRemoveFind_OneEntry) {
SimpleHashtable h;
ssize_t index = find(h, -1, 8);
ASSERT_EQ(-1, index);
index = add(h, 8, 1);
ASSERT_EQ(1U, h.size());
ASSERT_EQ(index, find(h, -1, 8));
ASSERT_EQ(8, h.entryAt(index).key);
ASSERT_EQ(1, h.entryAt(index).value);
index = find(h, index, 8);
ASSERT_EQ(-1, index);
ASSERT_TRUE(remove(h, 8));
ASSERT_EQ(0U, h.size());
index = find(h, -1, 8);
ASSERT_EQ(-1, index);
}
TEST_F(BasicHashtableTest, FindAddFindRemoveFind_MultipleEntryWithUniqueKey) {
const size_t N = 11;
SimpleHashtable h;
for (size_t i = 0; i < N; i++) {
ssize_t index = find(h, -1, int(i));
ASSERT_EQ(-1, index);
index = add(h, int(i), int(i * 10));
ASSERT_EQ(i + 1, h.size());
ASSERT_EQ(index, find(h, -1, int(i)));
ASSERT_EQ(int(i), h.entryAt(index).key);
ASSERT_EQ(int(i * 10), h.entryAt(index).value);
index = find(h, index, int(i));
ASSERT_EQ(-1, index);
}
for (size_t i = N; --i > 0; ) {
ASSERT_TRUE(remove(h, int(i))) << "i = " << i;
ASSERT_EQ(i, h.size());
ssize_t index = find(h, -1, int(i));
ASSERT_EQ(-1, index);
}
}
TEST_F(BasicHashtableTest, FindAddFindRemoveFind_MultipleEntryWithDuplicateKey) {
const size_t N = 11;
const int K = 1;
SimpleHashtable h;
for (size_t i = 0; i < N; i++) {
ssize_t index = find(h, -1, K);
if (i == 0) {
ASSERT_EQ(-1, index);
} else {
ASSERT_NE(-1, index);
}
add(h, K, int(i));
ASSERT_EQ(i + 1, h.size());
index = -1;
int values = 0;
for (size_t j = 0; j <= i; j++) {
index = find(h, index, K);
ASSERT_GE(index, 0);
ASSERT_EQ(K, h.entryAt(index).key);
values |= 1 << h.entryAt(index).value;
}
ASSERT_EQ(values, (1 << (i + 1)) - 1);
index = find(h, index, K);
ASSERT_EQ(-1, index);
}
for (size_t i = N; --i > 0; ) {
ASSERT_TRUE(remove(h, K)) << "i = " << i;
ASSERT_EQ(i, h.size());
ssize_t index = -1;
for (size_t j = 0; j < i; j++) {
index = find(h, index, K);
ASSERT_GE(index, 0);
ASSERT_EQ(K, h.entryAt(index).key);
}
index = find(h, index, K);
ASSERT_EQ(-1, index);
}
}
TEST_F(BasicHashtableTest, Clear_WhenAlreadyEmpty_DoesNothing) {
SimpleHashtable h;
h.clear();
EXPECT_EQ(0U, h.size());
EXPECT_EQ(3U, h.capacity());
EXPECT_EQ(5U, h.bucketCount());
EXPECT_EQ(0.75f, h.loadFactor());
}
TEST_F(BasicHashtableTest, Clear_AfterElementsAdded_RemovesThem) {
SimpleHashtable h;
add(h, 0, 0);
add(h, 1, 0);
h.clear();
EXPECT_EQ(0U, h.size());
EXPECT_EQ(3U, h.capacity());
EXPECT_EQ(5U, h.bucketCount());
EXPECT_EQ(0.75f, h.loadFactor());
}
TEST_F(BasicHashtableTest, Clear_AfterElementsAdded_DestroysThem) {
ComplexHashtable h;
add(h, ComplexKey(0), ComplexValue(0));
add(h, ComplexKey(1), ComplexValue(0));
ASSERT_NO_FATAL_FAILURE(assertInstanceCount(2, 2));
h.clear();
ASSERT_NO_FATAL_FAILURE(assertInstanceCount(0, 0));
EXPECT_EQ(0U, h.size());
EXPECT_EQ(3U, h.capacity());
EXPECT_EQ(5U, h.bucketCount());
EXPECT_EQ(0.75f, h.loadFactor());
}
TEST_F(BasicHashtableTest, Remove_AfterElementsAdded_DestroysThem) {
ComplexHashtable h;
add(h, ComplexKey(0), ComplexValue(0));
add(h, ComplexKey(1), ComplexValue(0));
ASSERT_NO_FATAL_FAILURE(assertInstanceCount(2, 2));
ASSERT_TRUE(remove(h, ComplexKey(0)));
ASSERT_NO_FATAL_FAILURE(assertInstanceCount(1, 1));
ASSERT_TRUE(remove(h, ComplexKey(1)));
ASSERT_NO_FATAL_FAILURE(assertInstanceCount(0, 0));
EXPECT_EQ(0U, h.size());
EXPECT_EQ(3U, h.capacity());
EXPECT_EQ(5U, h.bucketCount());
EXPECT_EQ(0.75f, h.loadFactor());
}
TEST_F(BasicHashtableTest, Destructor_AfterElementsAdded_DestroysThem) {
{
ComplexHashtable h;
add(h, ComplexKey(0), ComplexValue(0));
add(h, ComplexKey(1), ComplexValue(0));
ASSERT_NO_FATAL_FAILURE(assertInstanceCount(2, 2));
} // h is destroyed here
ASSERT_NO_FATAL_FAILURE(assertInstanceCount(0, 0));
}
TEST_F(BasicHashtableTest, Next_WhenEmpty_ReturnsMinusOne) {
SimpleHashtable h;
ASSERT_EQ(-1, h.next(-1));
}
TEST_F(BasicHashtableTest, Next_WhenNonEmpty_IteratesOverAllEntries) {
const int N = 88;
SimpleHashtable h;
for (int i = 0; i < N; i++) {
add(h, i, i * 10);
}
bool set[N];
memset(set, 0, sizeof(bool) * N);
int count = 0;
for (ssize_t index = -1; (index = h.next(index)) != -1; ) {
ASSERT_GE(index, 0);
ASSERT_LT(size_t(index), h.bucketCount());
const SimpleEntry& entry = h.entryAt(index);
ASSERT_GE(entry.key, 0);
ASSERT_LT(entry.key, N);
ASSERT_FALSE(set[entry.key]);
ASSERT_EQ(entry.key * 10, entry.value);
set[entry.key] = true;
count += 1;
}
ASSERT_EQ(N, count);
}
TEST_F(BasicHashtableTest, Add_RehashesOnDemand) {
SimpleHashtable h;
size_t initialCapacity = h.capacity();
size_t initialBucketCount = h.bucketCount();
for (size_t i = 0; i < initialCapacity; i++) {
add(h, int(i), 0);
}
EXPECT_EQ(initialCapacity, h.size());
EXPECT_EQ(initialCapacity, h.capacity());
EXPECT_EQ(initialBucketCount, h.bucketCount());
add(h, -1, -1);
EXPECT_EQ(initialCapacity + 1, h.size());
EXPECT_GT(h.capacity(), initialCapacity);
EXPECT_GT(h.bucketCount(), initialBucketCount);
EXPECT_GT(h.bucketCount(), h.capacity());
}
TEST_F(BasicHashtableTest, Rehash_WhenCapacityAndBucketCountUnchanged_DoesNothing) {
ComplexHashtable h;
add(h, ComplexKey(0), ComplexValue(0));
const void* oldBuckets = getBuckets(h);
ASSERT_NE((void*)NULL, oldBuckets);
ASSERT_NO_FATAL_FAILURE(assertInstanceCount(1, 1));
h.rehash(h.capacity(), h.loadFactor());
ASSERT_EQ(oldBuckets, getBuckets(h));
ASSERT_NO_FATAL_FAILURE(assertInstanceCount(1, 1));
}
TEST_F(BasicHashtableTest, Rehash_WhenEmptyAndHasNoBuckets_ButDoesNotAllocateBuckets) {
ComplexHashtable h;
ASSERT_EQ((void*)NULL, getBuckets(h));
ASSERT_NO_FATAL_FAILURE(assertInstanceCount(0, 0));
h.rehash(9, 1.0f);
EXPECT_EQ(0U, h.size());
EXPECT_EQ(10U, h.capacity());
EXPECT_EQ(11U, h.bucketCount());
EXPECT_EQ(1.0f, h.loadFactor());
EXPECT_EQ((void*)NULL, getBuckets(h));
ASSERT_NO_FATAL_FAILURE(assertInstanceCount(0, 0));
}
TEST_F(BasicHashtableTest, Rehash_WhenEmptyAndHasBuckets_ReleasesBucketsAndSetsCapacity) {
ComplexHashtable h(10);
add(h, ComplexKey(0), ComplexValue(0));
ASSERT_TRUE(remove(h, ComplexKey(0)));
ASSERT_NE((void*)NULL, getBuckets(h));
ASSERT_NO_FATAL_FAILURE(assertInstanceCount(0, 0));
h.rehash(0, 0.75f);
EXPECT_EQ(0U, h.size());
EXPECT_EQ(3U, h.capacity());
EXPECT_EQ(5U, h.bucketCount());
EXPECT_EQ(0.75f, h.loadFactor());
EXPECT_EQ((void*)NULL, getBuckets(h));
ASSERT_NO_FATAL_FAILURE(assertInstanceCount(0, 0));
}
TEST_F(BasicHashtableTest, Rehash_WhenLessThanCurrentCapacity_ShrinksBuckets) {
ComplexHashtable h(10);
add(h, ComplexKey(0), ComplexValue(0));
add(h, ComplexKey(1), ComplexValue(1));
const void* oldBuckets = getBuckets(h);
ASSERT_NO_FATAL_FAILURE(assertInstanceCount(2, 2));
h.rehash(0, 0.75f);
EXPECT_EQ(2U, h.size());
EXPECT_EQ(3U, h.capacity());
EXPECT_EQ(5U, h.bucketCount());
EXPECT_EQ(0.75f, h.loadFactor());
EXPECT_NE(oldBuckets, getBuckets(h));
ASSERT_NO_FATAL_FAILURE(assertInstanceCount(2, 2));
}
TEST_F(BasicHashtableTest, CopyOnWrite) {
ComplexHashtable h1;
add(h1, ComplexKey(0), ComplexValue(0));
add(h1, ComplexKey(1), ComplexValue(1));
const void* originalBuckets = getBuckets(h1);
ASSERT_NO_FATAL_FAILURE(assertInstanceCount(2, 2));
ssize_t index0 = find(h1, -1, ComplexKey(0));
EXPECT_GE(index0, 0);
// copy constructor acquires shared reference
ComplexHashtable h2(h1);
ASSERT_NO_FATAL_FAILURE(assertInstanceCount(2, 2));
ASSERT_EQ(originalBuckets, getBuckets(h2));
EXPECT_EQ(h1.size(), h2.size());
EXPECT_EQ(h1.capacity(), h2.capacity());
EXPECT_EQ(h1.bucketCount(), h2.bucketCount());
EXPECT_EQ(h1.loadFactor(), h2.loadFactor());
EXPECT_EQ(index0, find(h2, -1, ComplexKey(0)));
// operator= acquires shared reference
ComplexHashtable h3;
h3 = h2;
ASSERT_NO_FATAL_FAILURE(assertInstanceCount(2, 2));
ASSERT_EQ(originalBuckets, getBuckets(h3));
EXPECT_EQ(h1.size(), h3.size());
EXPECT_EQ(h1.capacity(), h3.capacity());
EXPECT_EQ(h1.bucketCount(), h3.bucketCount());
EXPECT_EQ(h1.loadFactor(), h3.loadFactor());
EXPECT_EQ(index0, find(h3, -1, ComplexKey(0)));
// editEntryAt copies shared contents
h1.editEntryAt(index0).value.v = 42;
ASSERT_NO_FATAL_FAILURE(assertInstanceCount(4, 4));
ASSERT_NE(originalBuckets, getBuckets(h1));
EXPECT_EQ(42, h1.entryAt(index0).value.v);
EXPECT_EQ(0, h2.entryAt(index0).value.v);
EXPECT_EQ(0, h3.entryAt(index0).value.v);
// clear releases reference to shared contents
h2.clear();
ASSERT_NO_FATAL_FAILURE(assertInstanceCount(4, 4));
EXPECT_EQ(0U, h2.size());
ASSERT_NE(originalBuckets, getBuckets(h2));
// operator= acquires shared reference, destroys unshared contents
h1 = h3;
ASSERT_NO_FATAL_FAILURE(assertInstanceCount(2, 2));
ASSERT_EQ(originalBuckets, getBuckets(h1));
EXPECT_EQ(h3.size(), h1.size());
EXPECT_EQ(h3.capacity(), h1.capacity());
EXPECT_EQ(h3.bucketCount(), h1.bucketCount());
EXPECT_EQ(h3.loadFactor(), h1.loadFactor());
EXPECT_EQ(index0, find(h1, -1, ComplexKey(0)));
// add copies shared contents
add(h1, ComplexKey(2), ComplexValue(2));
ASSERT_NO_FATAL_FAILURE(assertInstanceCount(5, 5));
ASSERT_NE(originalBuckets, getBuckets(h1));
EXPECT_EQ(3U, h1.size());
EXPECT_EQ(0U, h2.size());
EXPECT_EQ(2U, h3.size());
// remove copies shared contents
h1 = h3;
ASSERT_NO_FATAL_FAILURE(assertInstanceCount(2, 2));
ASSERT_EQ(originalBuckets, getBuckets(h1));
h1.removeAt(index0);
ASSERT_NO_FATAL_FAILURE(assertInstanceCount(3, 3));
ASSERT_NE(originalBuckets, getBuckets(h1));
EXPECT_EQ(1U, h1.size());
EXPECT_EQ(0U, h2.size());
EXPECT_EQ(2U, h3.size());
// rehash copies shared contents
h1 = h3;
ASSERT_NO_FATAL_FAILURE(assertInstanceCount(2, 2));
ASSERT_EQ(originalBuckets, getBuckets(h1));
h1.rehash(10, 1.0f);
ASSERT_NO_FATAL_FAILURE(assertInstanceCount(4, 4));
ASSERT_NE(originalBuckets, getBuckets(h1));
EXPECT_EQ(2U, h1.size());
EXPECT_EQ(0U, h2.size());
EXPECT_EQ(2U, h3.size());
}
} // namespace android