new hashlib::pool<> (derived from new dict)

This commit is contained in:
Clifford Wolf 2014-12-31 04:19:04 +01:00
parent c4bd6cb9d3
commit 429ccb62a1
1 changed files with 158 additions and 228 deletions

View File

@ -289,13 +289,13 @@ class dict
public:
class iterator
{
friend dict<K, T, OPS>;
friend dict;
protected:
dict<K, T, OPS> *ptr;
dict *ptr;
int index;
public:
iterator() { }
iterator(dict<K, T, OPS> *ptr, int index) : ptr(ptr), index(index) { }
iterator(dict *ptr, int index) : ptr(ptr), index(index) { }
iterator operator++() { index--; return *this; }
bool operator==(const iterator &other) const { return index == other.index; }
bool operator!=(const iterator &other) const { return index != other.index; }
@ -307,13 +307,13 @@ public:
class const_iterator
{
friend dict<K, T, OPS>;
friend dict;
protected:
const dict<K, T, OPS> *ptr;
const dict *ptr;
int index;
public:
const_iterator() { }
const_iterator(const dict<K, T, OPS> *ptr, int index) : ptr(ptr), index(index) { }
const_iterator(const dict *ptr, int index) : ptr(ptr), index(index) { }
const_iterator operator++() { index--; return *this; }
bool operator==(const const_iterator &other) const { return index == other.index; }
bool operator!=(const const_iterator &other) const { return index != other.index; }
@ -325,24 +325,24 @@ public:
{
}
dict(const dict<K, T, OPS> &other)
dict(const dict &other)
{
entries = other.entries;
do_rehash();
}
dict(dict<K, T, OPS> &&other)
dict(dict &&other)
{
swap(other);
}
dict<K, T, OPS> &operator=(const dict<K, T, OPS> &other) {
dict &operator=(const dict &other) {
entries = other.entries;
do_rehash();
return *this;
}
dict<K, T, OPS> &operator=(dict<K, T, OPS> &&other) {
dict &operator=(dict &&other) {
clear();
swap(other);
return *this;
@ -443,13 +443,13 @@ public:
return entries[i].udata.second;
}
void swap(dict<K, T, OPS> &other)
void swap(dict &other)
{
hashtable.swap(other.hashtable);
entries.swap(other.entries);
}
bool operator==(const dict<K, T, OPS> &other) const {
bool operator==(const dict &other) const {
if (size() != other.size())
return false;
for (auto &it : entries) {
@ -460,7 +460,7 @@ public:
return true;
}
bool operator!=(const dict<K, T, OPS> &other) const {
bool operator!=(const dict &other) const {
return !(*this == other);
}
@ -475,54 +475,38 @@ public:
const_iterator end() const { return const_iterator(nullptr, -1); }
};
// ********************************************************************************
// ********************************************************************************
// ********************************************************************************
// ********************************************************************************
// ********************************************************************************
template<typename K, typename OPS = hash_ops<K>>
class pool
{
struct entry_t
{
int link;
K key;
K udata;
int next;
entry_t() : link(-1) { }
entry_t(const K &key) : link(1), key(key) { }
bool is_free() const { return link < 0; }
int get_next() const { return (link > 0 ? link : -link) - 2; }
bool get_last() const { return get_next() == -1; }
void set_next_used(int next) { link = next + 2; }
void set_next_free(int next) { link = -(next + 2); }
entry_t() { }
entry_t(const K &udata, int next) : udata(udata), next(next) { }
};
std::vector<int> hashtable;
std::vector<entry_t> entries;
int free_list, counter, begin_n;
int begin_seek_count;
OPS ops;
void init()
{
free_list = -1;
counter = 0;
begin_n = -1;
begin_seek_count = 0;
#if 0
static inline void do_assert(bool cond) {
if (!cond) throw std::runtime_error("pool<> assert failed.");
}
#else
static inline void do_assert(bool) { }
#endif
void init_from(const pool<K, OPS> &other)
{
hashtable.clear();
entries.clear();
counter = other.size();
begin_n = counter - 1;
entries.reserve(counter);
for (auto &it : other)
entries.push_back(entry_t(it));
rehash();
}
int mkhash(const K &key) const
int do_hash(const K &key) const
{
unsigned int hash = 0;
if (!hashtable.empty())
@ -530,190 +514,152 @@ class pool
return hash;
}
void upd_begin_n(bool do_refree = true)
void do_rehash()
{
if (begin_n < -1) {
begin_n = -(begin_n+2);
while (begin_n >= 0 && entries[begin_n].is_free()) { begin_seek_count++; begin_n--; }
if (do_refree && begin_seek_count > int(entries.size() / 2)) refree();
}
}
void refree()
{
free_list = -1;
begin_n = -1;
int last_free = -1;
for (int i = 0; i < int(entries.size()); i++)
if (entries[i].is_free()) {
if (last_free != -1)
entries[last_free].set_next_free(i);
else
free_list = i;
last_free = i;
} else
begin_n = i;
if (last_free != -1)
entries[last_free].set_next_free(-1);
begin_seek_count = 0;
}
void rehash()
{
upd_begin_n(false);
entries.resize(begin_n + 1);
free_list = -1;
begin_n = -1;
hashtable.clear();
hashtable.resize(hashtable_size(entries.size() * hashtable_size_factor), -1);
int last_free = -1;
for (int i = 0; i < int(entries.size()); i++)
if (entries[i].is_free()) {
if (last_free != -1)
entries[last_free].set_next_free(i);
else
free_list = i;
last_free = i;
} else {
int hash = mkhash(entries[i].key);
entries[i].set_next_used(hashtable[hash]);
hashtable[hash] = i;
begin_n = i;
}
if (last_free != -1)
entries[last_free].set_next_free(-1);
begin_seek_count = 0;
}
int do_erase(const K &key, int hash)
{
int last_index = -1;
int index = hashtable.empty() ? -1 : hashtable[hash];
while (1) {
if (index < 0)
return 0;
if (ops.cmp(entries[index].key, key)) {
if (last_index < 0)
hashtable[hash] = entries[index].get_next();
else
entries[last_index].set_next_used(entries[index].get_next());
entries[index].key = K();
entries[index].set_next_free(free_list);
free_list = index;
if (--counter == 0)
clear();
else if (index == begin_n)
begin_n = -(begin_n+2);
return 1;
}
last_index = index;
index = entries[index].get_next();
for (int i = 0; i < int(entries.size()); i++) {
do_assert(-1 <= entries[i].next && entries[i].next < int(entries.size()));
int hash = do_hash(entries[i].udata);
entries[i].next = hashtable[hash];
hashtable[hash] = i;
}
}
int lookup_index(const K &key, int hash) const
int do_erase(int index, int hash)
{
int index = hashtable.empty() ? -1 : hashtable[hash];
while (1) {
if (index < 0)
return -1;
if (ops.cmp(entries[index].key, key))
return index;
index = entries[index].get_next();
}
}
do_assert(index < int(entries.size()));
if (hashtable.empty() || index < 0)
return 0;
int insert_at(const K &key, int hash)
{
if (free_list < 0)
int k = hashtable[hash];
if (k == index) {
hashtable[hash] = entries[index].next;
} else {
while (entries[k].next != index) {
k = entries[k].next;
do_assert(0 <= k && k < int(entries.size()));
}
entries[k].next = entries[index].next;
}
int back_idx = entries.size()-1;
if (index != back_idx)
{
free_list = entries.size();
entries.push_back(entry_t());
int back_hash = do_hash(entries[back_idx].udata);
if (entries.size() * hashtable_size_trigger > hashtable.size()) {
int i = free_list;
entries[i].key = key;
entries[i].set_next_used(0);
begin_n = i;
counter++;
rehash();
return i;
k = hashtable[back_hash];
if (k == back_idx) {
hashtable[back_hash] = index;
} else {
while (entries[k].next != back_idx) {
k = entries[k].next;
do_assert(0 <= k && k < int(entries.size()));
}
entries[k].next = index;
}
entries[index] = std::move(entries[back_idx]);
}
int i = free_list;
free_list = entries[i].get_next();
entries[i].key = key;
entries[i].set_next_used(hashtable[hash]);
hashtable[hash] = i;
if ((begin_n < -1 && -(begin_n+2) <= i) || (begin_n >= -1 && begin_n <= i))
begin_n = i;
counter++;
return i;
entries.pop_back();
if (entries.empty())
hashtable.clear();
return 1;
}
int do_lookup(const K &key, int &hash) const
{
if (hashtable.empty())
return -1;
if (entries.size() * hashtable_size_trigger > hashtable.size()) {
((pool*)this)->do_rehash();
hash = do_hash(key);
}
int index = hashtable[hash];
while (index >= 0 && !ops.cmp(entries[index].udata, key)) {
index = entries[index].next;
do_assert(-1 <= index && index < int(entries.size()));
}
return index;
}
int do_insert(const K &value, int &hash)
{
if (hashtable.empty()) {
entries.push_back(entry_t(value, -1));
do_rehash();
hash = do_hash(value);
} else {
entries.push_back(entry_t(value, hashtable[hash]));
hashtable[hash] = entries.size() - 1;
}
return entries.size() - 1;
}
public:
class iterator
{
pool<K, OPS> *ptr;
friend pool;
protected:
pool *ptr;
int index;
public:
iterator() { }
iterator(pool<K, OPS> *ptr, int index) : ptr(ptr), index(index) { }
iterator operator++() { do index--; while (index >= 0 && ptr->entries[index].is_free()); return *this; }
iterator(pool *ptr, int index) : ptr(ptr), index(index) { }
iterator operator++() { index--; return *this; }
bool operator==(const iterator &other) const { return index == other.index; }
bool operator!=(const iterator &other) const { return index != other.index; }
K &operator*() { return ptr->entries[index].key; }
K *operator->() { return &ptr->entries[index].key; }
const K &operator*() const { return ptr->entries[index].key; }
const K *operator->() const { return &ptr->entries[index].key; }
const K &operator*() const { return ptr->entries[index].udata; }
const K *operator->() const { return &ptr->entries[index].udata; }
};
class const_iterator
{
const pool<K, OPS> *ptr;
friend pool;
protected:
const pool *ptr;
int index;
public:
const_iterator() { }
const_iterator(const pool<K, OPS> *ptr, int index) : ptr(ptr), index(index) { }
const_iterator operator++() { do index--; while (index >= 0 && ptr->entries[index].is_free()); return *this; }
const_iterator(const pool *ptr, int index) : ptr(ptr), index(index) { }
const_iterator operator++() { index--; return *this; }
bool operator==(const const_iterator &other) const { return index == other.index; }
bool operator!=(const const_iterator &other) const { return index != other.index; }
const K &operator*() const { return ptr->entries[index].key; }
const K *operator->() const { return &ptr->entries[index].key; }
const K &operator*() const { return ptr->entries[index].udata; }
const K *operator->() const { return &ptr->entries[index].udata; }
};
pool()
{
init();
}
pool(const pool<K, OPS> &other)
pool(const pool &other)
{
init_from(other);
entries = other.entries;
do_rehash();
}
pool(pool<K, OPS> &&other)
pool(pool &&other)
{
init();
swap(other);
}
pool<K, OPS> &operator=(const pool<K, OPS> &other) {
if (this != &other)
init_from(other);
pool &operator=(const pool &other) {
entries = other.entries;
do_rehash();
return *this;
}
pool<K, OPS> &operator=(pool<K, OPS> &&other) {
pool &operator=(pool &&other) {
clear();
swap(other);
return *this;
@ -721,7 +667,6 @@ public:
pool(const std::initializer_list<K> &list)
{
init();
for (auto &it : list)
insert(it);
}
@ -729,7 +674,6 @@ public:
template<class InputIterator>
pool(InputIterator first, InputIterator last)
{
init();
insert(first, last);
}
@ -740,40 +684,41 @@ public:
insert(*first);
}
std::pair<iterator, bool> insert(const K &key)
std::pair<iterator, bool> insert(const K &value)
{
int hash = mkhash(key);
int i = lookup_index(key, hash);
int hash = do_hash(value);
int i = do_lookup(value, hash);
if (i >= 0)
return std::pair<iterator, bool>(iterator(this, i), false);
i = insert_at(key, hash);
i = do_insert(value, hash);
return std::pair<iterator, bool>(iterator(this, i), true);
}
int erase(const K &key)
{
int hash = mkhash(key);
return do_erase(key, hash);
int hash = do_hash(key);
int index = do_lookup(key, hash);
return do_erase(index, hash);
}
iterator erase(iterator it)
{
int hash = mkhash(*it);
do_erase(*it, hash);
int hash = do_hash(it->first);
do_erase(it.index, hash);
return ++it;
}
int count(const K &key) const
{
int hash = mkhash(key);
int i = lookup_index(key, hash);
int hash = do_hash(key);
int i = do_lookup(key, hash);
return i < 0 ? 0 : 1;
}
iterator find(const K &key)
{
int hash = mkhash(key);
int i = lookup_index(key, hash);
int hash = do_hash(key);
int i = do_lookup(key, hash);
if (i < 0)
return end();
return iterator(this, i);
@ -781,62 +726,47 @@ public:
const_iterator find(const K &key) const
{
int hash = mkhash(key);
int i = lookup_index(key, hash);
int hash = do_hash(key);
int i = do_lookup(key, hash);
if (i < 0)
return end();
return const_iterator(this, i);
}
bool operator[](const K &key) const
bool operator[](const K &key)
{
int hash = mkhash(key);
int i = lookup_index(key, hash);
int hash = do_hash(key);
int i = do_lookup(key, hash);
return i >= 0;
}
void swap(pool<K, OPS> &other)
void swap(pool &other)
{
hashtable.swap(other.hashtable);
entries.swap(other.entries);
std::swap(free_list, other.free_list);
std::swap(counter, other.counter);
std::swap(begin_n, other.begin_n);
std::swap(begin_seek_count, other.begin_seek_count);
}
bool operator==(const pool<K, OPS> &other) const {
if (counter != other.counter)
bool operator==(const pool &other) const {
if (size() != other.size())
return false;
if (counter == 0)
return true;
if (entries.size() < other.entries.size())
for (auto &it : *this) {
auto oit = other.find(it.first);
if (oit == other.end() || oit->second != it.second)
return false;
}
else
for (auto &oit : other) {
auto it = find(oit.first);
if (it == end() || it->second != oit.second)
return false;
}
for (auto &it : entries)
if (!other.count(it.udata))
return false;
return true;
}
bool operator!=(const pool<K, OPS> &other) const {
bool operator!=(const pool &other) const {
return !(*this == other);
}
size_t size() const { return counter; }
bool empty() const { return counter == 0; }
void clear() { hashtable.clear(); entries.clear(); init(); }
size_t size() const { return entries.size(); }
bool empty() const { return entries.empty(); }
void clear() { hashtable.clear(); entries.clear(); }
iterator begin() { upd_begin_n(); return iterator(this, begin_n); }
iterator begin() { return iterator(this, int(entries.size())-1); }
iterator end() { return iterator(nullptr, -1); }
const_iterator begin() const { ((pool*)this)->upd_begin_n(); return const_iterator(this, begin_n); }
const_iterator begin() const { return const_iterator(this, int(entries.size())-1); }
const_iterator end() const { return const_iterator(nullptr, -1); }
};