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-rw-r--r--kernel/hashlib.h887
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diff --git a/kernel/hashlib.h b/kernel/hashlib.h
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+++ b/kernel/hashlib.h
@@ -0,0 +1,887 @@
+// This is free and unencumbered software released into the public domain.
+//
+// Anyone is free to copy, modify, publish, use, compile, sell, or
+// distribute this software, either in source code form or as a compiled
+// binary, for any purpose, commercial or non-commercial, and by any
+// means.
+
+// -------------------------------------------------------
+// Written by Clifford Wolf <clifford@clifford.at> in 2014
+// -------------------------------------------------------
+
+#ifndef HASHLIB_H
+
+#include <stdexcept>
+#include <algorithm>
+#include <string>
+#include <vector>
+
+namespace hashlib {
+
+const int hashtable_size_trigger = 2;
+const int hashtable_size_factor = 3;
+
+// The XOR version of DJB2
+inline unsigned int mkhash(unsigned int a, unsigned int b) {
+ return ((a << 5) + a) ^ b;
+}
+
+// traditionally 5381 is used as starting value for the djb2 hash
+const unsigned int mkhash_init = 5381;
+
+// The ADD version of DJB2
+// (usunsigned int mkhashe this version for cache locality in b)
+inline unsigned int mkhash_add(unsigned int a, unsigned int b) {
+ return ((a << 5) + a) + b;
+}
+
+inline unsigned int mkhash_xorshift(unsigned int a) {
+ if (sizeof(a) == 4) {
+ a ^= a << 13;
+ a ^= a >> 17;
+ a ^= a << 5;
+ } else if (sizeof(a) == 8) {
+ a ^= a << 13;
+ a ^= a >> 7;
+ a ^= a << 17;
+ } else
+ throw std::runtime_error("mkhash_xorshift() only implemented for 32 bit and 64 bit ints");
+ return a;
+}
+
+template<typename T> struct hash_ops {
+ static inline bool cmp(const T &a, const T &b) {
+ return a == b;
+ }
+ static inline unsigned int hash(const T &a) {
+ return a.hash();
+ }
+};
+
+template<> struct hash_ops<int> {
+ template<typename T>
+ static inline bool cmp(T a, T b) {
+ return a == b;
+ }
+ template<typename T>
+ static inline unsigned int hash(T a) {
+ return a;
+ }
+};
+
+template<> struct hash_ops<std::string> {
+ static inline bool cmp(const std::string &a, const std::string &b) {
+ return a == b;
+ }
+ static inline unsigned int hash(const std::string &a) {
+ unsigned int v = 0;
+ for (auto c : a)
+ v = mkhash(v, c);
+ return v;
+ }
+};
+
+template<typename P, typename Q> struct hash_ops<std::pair<P, Q>> {
+ static inline bool cmp(std::pair<P, Q> a, std::pair<P, Q> b) {
+ return a == b;
+ }
+ static inline unsigned int hash(std::pair<P, Q> a) {
+ hash_ops<P> p_ops;
+ hash_ops<Q> q_ops;
+ return mkhash(p_ops.hash(a.first), q_ops.hash(a.second));
+ }
+};
+
+template<typename T> struct hash_ops<std::vector<T>> {
+ static inline bool cmp(std::vector<T> a, std::vector<T> b) {
+ return a == b;
+ }
+ static inline unsigned int hash(std::vector<T> a) {
+ hash_ops<T> t_ops;
+ unsigned int h = mkhash_init;
+ for (auto k : a)
+ h = mkhash(h, t_ops.hash(k));
+ return h;
+ }
+};
+
+struct hash_cstr_ops {
+ static inline bool cmp(const char *a, const char *b) {
+ for (int i = 0; a[i] || b[i]; i++)
+ if (a[i] != b[i])
+ return false;
+ return true;
+ }
+ static inline unsigned int hash(const char *a) {
+ unsigned int hash = mkhash_init;
+ while (*a)
+ hash = mkhash(hash, *(a++));
+ return hash;
+ }
+};
+
+struct hash_ptr_ops {
+ static inline bool cmp(const void *a, const void *b) {
+ return a == b;
+ }
+ static inline unsigned int hash(const void *a) {
+ return (unsigned long)a;
+ }
+};
+
+struct hash_obj_ops {
+ static inline bool cmp(const void *a, const void *b) {
+ return a == b;
+ }
+ template<typename T>
+ static inline unsigned int hash(const T *a) {
+ return a->hash();
+ }
+};
+
+inline int hashtable_size(int min_size)
+{
+ static std::vector<int> zero_and_some_primes = {
+ 0, 23, 29, 37, 47, 59, 79, 101, 127, 163, 211, 269, 337, 431, 541, 677,
+ 853, 1069, 1361, 1709, 2137, 2677, 3347, 4201, 5261, 6577, 8231, 10289,
+ 12889, 16127, 20161, 25219, 31531, 39419, 49277, 61603, 77017, 96281,
+ 120371, 150473, 188107, 235159, 293957, 367453, 459317, 574157, 717697,
+ 897133, 1121423, 1401791, 1752239, 2190299, 2737937, 3422429, 4278037,
+ 5347553, 6684443, 8355563, 10444457, 13055587, 16319519, 20399411,
+ 25499291, 31874149, 39842687, 49803361, 62254207, 77817767, 97272239,
+ 121590311, 151987889, 189984863, 237481091, 296851369, 371064217
+ };
+
+ for (auto p : zero_and_some_primes)
+ if (p >= min_size) return p;
+
+ if (sizeof(int) == 4)
+ throw std::length_error("hash table exceeded maximum size. use a ILP64 abi for larger tables.");
+
+ for (auto p : zero_and_some_primes)
+ if (100129 * p > min_size) return 100129 * p;
+
+ throw std::length_error("hash table exceeded maximum size.");
+}
+
+template<typename K, typename T, typename OPS = hash_ops<K>> class dict;
+template<typename K, int offset = 0, typename OPS = hash_ops<K>> class idict;
+template<typename K, typename OPS = hash_ops<K>> class pool;
+
+template<typename K, typename T, typename OPS>
+class dict
+{
+ struct entry_t
+ {
+ std::pair<K, T> udata;
+ int next;
+
+ entry_t() { }
+ entry_t(const std::pair<K, T> &udata, int next) : udata(udata), next(next) { }
+ entry_t(std::pair<K, T> &&udata, int next) : udata(std::move(udata)), next(next) { }
+ };
+
+ std::vector<int> hashtable;
+ std::vector<entry_t> entries;
+ OPS ops;
+
+#ifdef NDEBUG
+ static inline void do_assert(bool) { }
+#else
+ static inline void do_assert(bool cond) {
+ if (!cond) throw std::runtime_error("dict<> assert failed.");
+ }
+#endif
+
+ int do_hash(const K &key) const
+ {
+ unsigned int hash = 0;
+ if (!hashtable.empty())
+ hash = ops.hash(key) % (unsigned int)(hashtable.size());
+ return hash;
+ }
+
+ void do_rehash()
+ {
+ hashtable.clear();
+ hashtable.resize(hashtable_size(entries.size() * hashtable_size_factor), -1);
+
+ 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.first);
+ entries[i].next = hashtable[hash];
+ hashtable[hash] = i;
+ }
+ }
+
+ int do_erase(int index, int hash)
+ {
+ do_assert(index < int(entries.size()));
+ if (hashtable.empty() || index < 0)
+ return 0;
+
+ int k = hashtable[hash];
+ do_assert(0 <= k && k < int(entries.size()));
+
+ 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)
+ {
+ int back_hash = do_hash(entries[back_idx].udata.first);
+
+ k = hashtable[back_hash];
+ do_assert(0 <= k && k < int(entries.size()));
+
+ 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]);
+ }
+
+ 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()) {
+ ((dict*)this)->do_rehash();
+ hash = do_hash(key);
+ }
+
+ int index = hashtable[hash];
+
+ while (index >= 0 && !ops.cmp(entries[index].udata.first, key)) {
+ index = entries[index].next;
+ do_assert(-1 <= index && index < int(entries.size()));
+ }
+
+ return index;
+ }
+
+ int do_insert(const K &key, int &hash)
+ {
+ if (hashtable.empty()) {
+ entries.push_back(entry_t(std::pair<K, T>(key, T()), -1));
+ do_rehash();
+ hash = do_hash(key);
+ } else {
+ entries.push_back(entry_t(std::pair<K, T>(key, T()), hashtable[hash]));
+ hashtable[hash] = entries.size() - 1;
+ }
+ return entries.size() - 1;
+ }
+
+ int do_insert(const std::pair<K, T> &value, int &hash)
+ {
+ if (hashtable.empty()) {
+ entries.push_back(entry_t(value, -1));
+ do_rehash();
+ hash = do_hash(value.first);
+ } else {
+ entries.push_back(entry_t(value, hashtable[hash]));
+ hashtable[hash] = entries.size() - 1;
+ }
+ return entries.size() - 1;
+ }
+
+public:
+ class const_iterator : public std::iterator<std::forward_iterator_tag, std::pair<K, T>>
+ {
+ friend class dict;
+ protected:
+ const dict *ptr;
+ int index;
+ const_iterator(const dict *ptr, int index) : ptr(ptr), index(index) { }
+ public:
+ const_iterator() { }
+ 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; }
+ bool operator!=(const const_iterator &other) const { return index != other.index; }
+ const std::pair<K, T> &operator*() const { return ptr->entries[index].udata; }
+ const std::pair<K, T> *operator->() const { return &ptr->entries[index].udata; }
+ };
+
+ class iterator : public std::iterator<std::forward_iterator_tag, std::pair<K, T>>
+ {
+ friend class dict;
+ protected:
+ dict *ptr;
+ int index;
+ iterator(dict *ptr, int index) : ptr(ptr), index(index) { }
+ public:
+ iterator() { }
+ 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; }
+ bool operator!=(const iterator &other) const { return index != other.index; }
+ std::pair<K, T> &operator*() { return ptr->entries[index].udata; }
+ std::pair<K, T> *operator->() { return &ptr->entries[index].udata; }
+ const std::pair<K, T> &operator*() const { return ptr->entries[index].udata; }
+ const std::pair<K, T> *operator->() const { return &ptr->entries[index].udata; }
+ operator const_iterator() const { return const_iterator(ptr, index); }
+ };
+
+ dict()
+ {
+ }
+
+ dict(const dict &other)
+ {
+ entries = other.entries;
+ do_rehash();
+ }
+
+ dict(dict &&other)
+ {
+ swap(other);
+ }
+
+ dict &operator=(const dict &other) {
+ entries = other.entries;
+ do_rehash();
+ return *this;
+ }
+
+ dict &operator=(dict &&other) {
+ clear();
+ swap(other);
+ return *this;
+ }
+
+ dict(const std::initializer_list<std::pair<K, T>> &list)
+ {
+ for (auto &it : list)
+ insert(it);
+ }
+
+ template<class InputIterator>
+ dict(InputIterator first, InputIterator last)
+ {
+ insert(first, last);
+ }
+
+ template<class InputIterator>
+ void insert(InputIterator first, InputIterator last)
+ {
+ for (; first != last; ++first)
+ insert(*first);
+ }
+
+ std::pair<iterator, bool> insert(const K &key)
+ {
+ int hash = do_hash(key);
+ int i = do_lookup(key, hash);
+ if (i >= 0)
+ return std::pair<iterator, bool>(iterator(this, i), false);
+ i = do_insert(key, hash);
+ return std::pair<iterator, bool>(iterator(this, i), true);
+ }
+
+ std::pair<iterator, bool> insert(const std::pair<K, T> &value)
+ {
+ int hash = do_hash(value.first);
+ int i = do_lookup(value.first, hash);
+ if (i >= 0)
+ return std::pair<iterator, bool>(iterator(this, i), false);
+ i = do_insert(value, hash);
+ return std::pair<iterator, bool>(iterator(this, i), true);
+ }
+
+ int erase(const K &key)
+ {
+ int hash = do_hash(key);
+ int index = do_lookup(key, hash);
+ return do_erase(index, hash);
+ }
+
+ iterator erase(iterator it)
+ {
+ int hash = do_hash(it->first);
+ do_erase(it.index, hash);
+ return ++it;
+ }
+
+ int count(const K &key) const
+ {
+ int hash = do_hash(key);
+ int i = do_lookup(key, hash);
+ return i < 0 ? 0 : 1;
+ }
+
+ int count(const K &key, const_iterator it) const
+ {
+ int hash = do_hash(key);
+ int i = do_lookup(key, hash);
+ return i < 0 || i > it.index ? 0 : 1;
+ }
+
+ iterator find(const K &key)
+ {
+ int hash = do_hash(key);
+ int i = do_lookup(key, hash);
+ if (i < 0)
+ return end();
+ return iterator(this, i);
+ }
+
+ const_iterator find(const K &key) const
+ {
+ int hash = do_hash(key);
+ int i = do_lookup(key, hash);
+ if (i < 0)
+ return end();
+ return const_iterator(this, i);
+ }
+
+ T& at(const K &key)
+ {
+ int hash = do_hash(key);
+ int i = do_lookup(key, hash);
+ if (i < 0)
+ throw std::out_of_range("dict::at()");
+ return entries[i].udata.second;
+ }
+
+ const T& at(const K &key) const
+ {
+ int hash = do_hash(key);
+ int i = do_lookup(key, hash);
+ if (i < 0)
+ throw std::out_of_range("dict::at()");
+ return entries[i].udata.second;
+ }
+
+ T& operator[](const K &key)
+ {
+ int hash = do_hash(key);
+ int i = do_lookup(key, hash);
+ if (i < 0)
+ i = do_insert(std::pair<K, T>(key, T()), hash);
+ return entries[i].udata.second;
+ }
+
+ template<typename Compare = std::less<K>>
+ void sort(Compare comp = Compare())
+ {
+ std::sort(entries.begin(), entries.end(), [comp](const entry_t &a, const entry_t &b){ return comp(b.udata.first, a.udata.first); });
+ do_rehash();
+ }
+
+ void swap(dict &other)
+ {
+ hashtable.swap(other.hashtable);
+ entries.swap(other.entries);
+ }
+
+ bool operator==(const dict &other) const {
+ if (size() != other.size())
+ return false;
+ for (auto &it : entries) {
+ auto oit = other.find(it.udata.first);
+ if (oit == other.end() || !(oit->second == it.udata.second))
+ return false;
+ }
+ return true;
+ }
+
+ bool operator!=(const dict &other) const {
+ return !operator==(other);
+ }
+
+ size_t size() const { return entries.size(); }
+ bool empty() const { return entries.empty(); }
+ void clear() { hashtable.clear(); entries.clear(); }
+
+ iterator begin() { return iterator(this, int(entries.size())-1); }
+ iterator end() { return iterator(nullptr, -1); }
+
+ const_iterator begin() const { return const_iterator(this, int(entries.size())-1); }
+ const_iterator end() const { return const_iterator(nullptr, -1); }
+};
+
+template<typename K, typename OPS>
+class pool
+{
+ template<typename, int, typename> friend class idict;
+
+protected:
+ struct entry_t
+ {
+ K udata;
+ int next;
+
+ entry_t() { }
+ entry_t(const K &udata, int next) : udata(udata), next(next) { }
+ };
+
+ std::vector<int> hashtable;
+ std::vector<entry_t> entries;
+ OPS ops;
+
+#ifdef NDEBUG
+ static inline void do_assert(bool) { }
+#else
+ static inline void do_assert(bool cond) {
+ if (!cond) throw std::runtime_error("pool<> assert failed.");
+ }
+#endif
+
+ int do_hash(const K &key) const
+ {
+ unsigned int hash = 0;
+ if (!hashtable.empty())
+ hash = ops.hash(key) % (unsigned int)(hashtable.size());
+ return hash;
+ }
+
+ void do_rehash()
+ {
+ hashtable.clear();
+ hashtable.resize(hashtable_size(entries.size() * hashtable_size_factor), -1);
+
+ 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 do_erase(int index, int hash)
+ {
+ do_assert(index < int(entries.size()));
+ if (hashtable.empty() || index < 0)
+ return 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)
+ {
+ int back_hash = do_hash(entries[back_idx].udata);
+
+ 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]);
+ }
+
+ 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 const_iterator : public std::iterator<std::forward_iterator_tag, K>
+ {
+ friend class pool;
+ protected:
+ const pool *ptr;
+ int index;
+ const_iterator(const pool *ptr, int index) : ptr(ptr), index(index) { }
+ public:
+ const_iterator() { }
+ 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].udata; }
+ const K *operator->() const { return &ptr->entries[index].udata; }
+ };
+
+ class iterator : public std::iterator<std::forward_iterator_tag, K>
+ {
+ friend class pool;
+ protected:
+ pool *ptr;
+ int index;
+ iterator(pool *ptr, int index) : ptr(ptr), index(index) { }
+ public:
+ iterator() { }
+ 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].udata; }
+ K *operator->() { return &ptr->entries[index].udata; }
+ const K &operator*() const { return ptr->entries[index].udata; }
+ const K *operator->() const { return &ptr->entries[index].udata; }
+ operator const_iterator() const { return const_iterator(ptr, index); }
+ };
+
+ pool()
+ {
+ }
+
+ pool(const pool &other)
+ {
+ entries = other.entries;
+ do_rehash();
+ }
+
+ pool(pool &&other)
+ {
+ swap(other);
+ }
+
+ pool &operator=(const pool &other) {
+ entries = other.entries;
+ do_rehash();
+ return *this;
+ }
+
+ pool &operator=(pool &&other) {
+ clear();
+ swap(other);
+ return *this;
+ }
+
+ pool(const std::initializer_list<K> &list)
+ {
+ for (auto &it : list)
+ insert(it);
+ }
+
+ template<class InputIterator>
+ pool(InputIterator first, InputIterator last)
+ {
+ insert(first, last);
+ }
+
+ template<class InputIterator>
+ void insert(InputIterator first, InputIterator last)
+ {
+ for (; first != last; ++first)
+ insert(*first);
+ }
+
+ std::pair<iterator, bool> insert(const K &value)
+ {
+ int hash = do_hash(value);
+ int i = do_lookup(value, hash);
+ if (i >= 0)
+ return std::pair<iterator, bool>(iterator(this, i), false);
+ i = do_insert(value, hash);
+ return std::pair<iterator, bool>(iterator(this, i), true);
+ }
+
+ int erase(const K &key)
+ {
+ int hash = do_hash(key);
+ int index = do_lookup(key, hash);
+ return do_erase(index, hash);
+ }
+
+ iterator erase(iterator it)
+ {
+ int hash = do_hash(*it);
+ do_erase(it.index, hash);
+ return ++it;
+ }
+
+ int count(const K &key) const
+ {
+ int hash = do_hash(key);
+ int i = do_lookup(key, hash);
+ return i < 0 ? 0 : 1;
+ }
+
+ int count(const K &key, const_iterator it) const
+ {
+ int hash = do_hash(key);
+ int i = do_lookup(key, hash);
+ return i < 0 || i > it.index ? 0 : 1;
+ }
+
+ iterator find(const K &key)
+ {
+ int hash = do_hash(key);
+ int i = do_lookup(key, hash);
+ if (i < 0)
+ return end();
+ return iterator(this, i);
+ }
+
+ const_iterator find(const K &key) const
+ {
+ 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)
+ {
+ int hash = do_hash(key);
+ int i = do_lookup(key, hash);
+ return i >= 0;
+ }
+
+ template<typename Compare = std::less<K>>
+ void sort(Compare comp = Compare())
+ {
+ std::sort(entries.begin(), entries.end(), [comp](const entry_t &a, const entry_t &b){ return comp(b.udata, a.udata); });
+ do_rehash();
+ }
+
+ void swap(pool &other)
+ {
+ hashtable.swap(other.hashtable);
+ entries.swap(other.entries);
+ }
+
+ bool operator==(const pool &other) const {
+ if (size() != other.size())
+ return false;
+ for (auto &it : entries)
+ if (!other.count(it.udata))
+ return false;
+ return true;
+ }
+
+ bool operator!=(const pool &other) const {
+ return !operator==(other);
+ }
+
+ size_t size() const { return entries.size(); }
+ bool empty() const { return entries.empty(); }
+ void clear() { hashtable.clear(); entries.clear(); }
+
+ iterator begin() { return iterator(this, int(entries.size())-1); }
+ iterator end() { return iterator(nullptr, -1); }
+
+ const_iterator begin() const { return const_iterator(this, int(entries.size())-1); }
+ const_iterator end() const { return const_iterator(nullptr, -1); }
+};
+
+template<typename K, int offset, typename OPS>
+class idict
+{
+ pool<K, OPS> database;
+
+public:
+ typedef typename pool<K, OPS>::const_iterator const_iterator;
+
+ int operator()(const K &key)
+ {
+ int hash = database.do_hash(key);
+ int i = database.do_lookup(key, hash);
+ if (i < 0)
+ i = database.do_insert(key, hash);
+ return i + offset;
+ }
+
+ int at(const K &key) const
+ {
+ int hash = database.do_hash(key);
+ int i = database.do_lookup(key, hash);
+ if (i < 0)
+ throw std::out_of_range("idict::at()");
+ return i + offset;
+ }
+
+ int count(const K &key) const
+ {
+ int hash = database.do_hash(key);
+ int i = database.do_lookup(key, hash);
+ return i < 0 ? 0 : 1;
+ }
+
+ void expect(const K &key, int i)
+ {
+ int j = (*this)(key);
+ if (i != j)
+ throw std::out_of_range("idict::expect()");
+ }
+
+ const K &operator[](int index) const
+ {
+ return database.entries.at(index - offset).udata;
+ }
+
+ const_iterator begin() const { return database.begin(); }
+ const_iterator end() const { return database.end(); }
+};
+
+} /* namespace hashlib */
+
+#endif