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ukui-search/libchinese-segmentation/storage-base/cedar/cedarpp.h

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删除子项目，upstream分支将只作为打包时同步代码的分支
2023-12-28 10:27:40 +08:00
// cedar -- C++ implementation of Efficiently-updatable Double ARray trie
// $Id: cedarpp.h 1916 2017-07-12 07:30:56Z ynaga $
// Copyright (c) 2009-2015 Naoki Yoshinaga <ynaga@tkl.iis.u-tokyo.ac.jp>
同步子项目
2024-01-30 14:42:09 +08:00
/*
* Copyright (C) 2023, KylinSoft Co., Ltd.
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <https://www.gnu.org/licenses/>.
*
*/
删除子项目，upstream分支将只作为打包时同步代码的分支
2023-12-28 10:27:40 +08:00
#ifndef CEDAR_H
#define CEDAR_H
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <climits>
#include <cassert>
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#define STATIC_ASSERT(e, msg) typedef char msg[(e) ? 1 : -1]
namespace cedar {
// typedefs
#if LONG_BIT == 64
typedef unsigned long npos_t; // possibly compatible with size_t
#else
typedef unsigned long long npos_t;
#endif
typedef unsigned char uchar;
static const npos_t TAIL_OFFSET_MASK = static_cast <npos_t> (0xffffffff);
static const npos_t NODE_INDEX_MASK = static_cast <npos_t> (0xffffffff) << 32;
template <typename T> struct NaN { enum { N1 = -1, N2 = -2 }; };
template <> struct NaN <float> { enum { N1 = 0x7f800001, N2 = 0x7f800002 }; };
static const int MAX_ALLOC_SIZE = 1 << 16; // must be divisible by 256
// dynamic double array
template <typename value_type,
const int NO_VALUE = NaN <value_type>::N1,
const int NO_PATH = NaN <value_type>::N2,
const bool ORDERED = true,
const int MAX_TRIAL = 1,
const size_t NUM_TRACKING_NODES = 0>
class da {
public:
enum error_code { CEDAR_NO_VALUE = NO_VALUE, CEDAR_NO_PATH = NO_PATH };
typedef value_type result_type;
struct result_pair_type {
value_type value;
size_t length; // prefix length
};
struct result_triple_type { // for predict ()
value_type value;
size_t length; // suffix length
npos_t id; // node id of value
};
struct node {
union { int base; value_type value; }; // negative means prev empty index
int check; // negative means next empty index
node (const int base_ = 0, const int check_ = 0)
: base (base_), check (check_) {}
};
struct ninfo { // x1.5 update speed; +.25 % memory (8n -> 10n)
uchar sibling; // right sibling (= 0 if not exist)
uchar child; // first child
ninfo () : sibling (0), child (0) {}
};
struct block { // a block w/ 256 elements
int prev; // prev block; 3 bytes
int next; // next block; 3 bytes
short num; // # empty elements; 0 - 256
short reject; // minimum # branching failed to locate; soft limit
int trial; // # trial
int ehead; // first empty item
block () : prev (0), next (0), num (256), reject (257), trial (0), ehead (0) {}
};
da () : tracking_node (), _array (0), _tail (0), _tail0 (0), _ninfo (0), _block (0), _bheadF (0), _bheadC (0), _bheadO (0), _capacity (0), _size (0), _quota (0), _quota0 (0), _no_delete (false), _reject () {
#pragma GCC diagnostic ignored "-Wunused-local-typedefs"
STATIC_ASSERT(sizeof (value_type) <= sizeof (int),
value_type_is_not_supported___maintain_a_value_array_by_yourself_and_store_its_index_to_trie
);
#pragma GCC diagnostic warning "-Wunused-local-typedefs"
_initialize ();
}
~da () { clear (false); }
size_t capacity () const { return static_cast <size_t> (_capacity); }
size_t size () const { return static_cast <size_t> (_size); }
size_t length () const { return static_cast <size_t> (*_length); }
size_t total_size () const { return sizeof (node) * _size; }
size_t unit_size () const { return sizeof (node); }
size_t nonzero_size () const {
size_t i = 0;
for (int to = 0; to < _size; ++to)
if (_array[to].check >= 0) ++i;
return i;
}
size_t nonzero_length () const {
size_t i (0), j (0);
for (int to = 0; to < _size; ++to) {
const node& n = _array[to];
if (n.check >= 0 && _array[n.check].base != to && n.base < 0)
{ ++j; for (const char* p = &_tail[-n.base]; *p; ++p) ++i; }
}
return i + j * (1 + sizeof (value_type));
}
size_t num_keys () const {
size_t i = 0;
for (int to = 0; to < _size; ++to) {
const node& n = _array[to];
if (n.check >= 0 && (_array[n.check].base == to || n.base < 0)) ++i;
}
return i;
}
// interfance
template <typename T>
T exactMatchSearch (const char* key) const
{ return exactMatchSearch <T> (key, std::strlen (key)); }
template <typename T>
T exactMatchSearch (const char* key, size_t len, npos_t from = 0) const {
union { int i; value_type x; } b;
size_t pos = 0;
b.i = _find (key, from, pos, len);
if (b.i == CEDAR_NO_PATH) b.i = CEDAR_NO_VALUE;
T result;
_set_result (&result, b.x, len, from);
return result;
}
template <typename T>
size_t commonPrefixSearch (const char* key, T* result, size_t result_len) const
{ return commonPrefixSearch (key, result, result_len, std::strlen (key)); }
template <typename T>
size_t commonPrefixSearch (const char* key, T* result, size_t result_len, size_t len, npos_t from = 0) const {
size_t num = 0;
for (size_t pos = 0; pos < len; ) {
union { int i; value_type x; } b;
b.i = _find (key, from, pos, pos + 1);
if (b.i == CEDAR_NO_VALUE) continue;
if (b.i == CEDAR_NO_PATH) return num;
if (num < result_len) _set_result (&result[num], b.x, pos, from);
++num;
}
return num;
}
// predict key from double array
template <typename T>
size_t commonPrefixPredict (const char* key, T* result, size_t result_len)
{ return commonPrefixPredict (key, result, result_len, std::strlen (key)); }
template <typename T>
size_t commonPrefixPredict (const char* key, T* result, size_t result_len, size_t len, npos_t from = 0) {
size_t num (0), pos (0), p (0);
if (_find (key, from, pos, len) == CEDAR_NO_PATH) return 0;
union { int i; value_type x; } b;
const npos_t root = from;
for (b.i = begin (from, p); b.i != CEDAR_NO_PATH; b.i = next (from, p, root)) {
if (num < result_len)
_set_result (&result[num], b.x, p, from);
++num;
}
return num;
}
void suffix (char* key, size_t len, npos_t to) const {
key[len] = '\0';
if (const int offset = static_cast <int> (to >> 32)) {
to &= TAIL_OFFSET_MASK;
size_t len_tail = std::strlen (&_tail[-_array[to].base]);
if (len > len_tail) len -= len_tail; else len_tail = len, len = 0;
std::memcpy (&key[len], &_tail[static_cast <size_t> (offset) - len_tail], len_tail);
}
while (len--) {
const int from = _array[to].check;
key[len] = static_cast <char> (_array[from].base ^ static_cast <int> (to));
to = static_cast <npos_t> (from);
}
}
value_type traverse (const char* key, npos_t& from, size_t& pos) const
{ return traverse (key, from, pos, std::strlen (key)); }
value_type traverse (const char* key, npos_t& from, size_t& pos, size_t len) const {
union { int i; value_type x; } b;
b.i = _find (key, from, pos, len);
return b.x;
}
struct empty_callback { void operator () (const int, const int) {} }; // dummy empty function
value_type& update (const char* key)
{ return update (key, std::strlen (key)); }
value_type& update (const char* key, size_t len, value_type val = value_type (0))
{ npos_t from (0); size_t pos (0); return update (key, from, pos, len, val); }
value_type& update (const char* key, npos_t& from, size_t& pos, size_t len, value_type val = value_type (0))
{ empty_callback cf; return update (key, from, pos, len, val, cf); }
template <typename T>
value_type& update (const char* key, npos_t& from, size_t& pos, size_t len, value_type val, T& cf) {
if (! len && ! from)
_err (__FILE__, __LINE__, "failed to insert zero-length key\n");
#ifndef USE_FAST_LOAD
if (! _ninfo || ! _block) restore ();
#endif
npos_t offset = from >> 32;
if (! offset) { // node on trie
for (const uchar* const key_ = reinterpret_cast <const uchar*> (key);
_array[from].base >= 0; ++pos) {
if (pos == len) // could be reduced
{ const int to = _follow (from, 0, cf); return _array[to].value += val; }
from = static_cast <size_t> (_follow (from, key_[pos], cf));
}
offset = static_cast <npos_t> (-_array[from].base);
}
if (offset >= sizeof (int)) { // go to _tail
const size_t pos_orig = pos;
char* const tail = &_tail[offset] - pos;
while (pos < len && key[pos] == tail[pos]) ++pos;
//
if (pos == len && tail[pos] == '\0') { // found exact key
if (const npos_t moved = pos - pos_orig) { // search end on tail
from &= TAIL_OFFSET_MASK;
from |= (offset + moved) << 32;
}
return *reinterpret_cast <value_type*> (&tail[len + 1]) += val;
}
// otherwise, insert the common prefix in tail if any
if (from >> 32) {
from &= TAIL_OFFSET_MASK; // reset to update tail offset
for (npos_t offset_ = static_cast <npos_t> (-_array[from].base);
offset_ < offset; ) {
from = static_cast <size_t>
(_follow (from, static_cast <uchar> (_tail[offset_]), cf));
++offset_;
// this shows intricacy in debugging updatable double array trie
if (NUM_TRACKING_NODES) // keep the traversed node (on tail) updated
for (size_t j = 0; tracking_node[j] != 0; ++j)
if (tracking_node[j] >> 32 == offset_)
tracking_node[j] = static_cast <npos_t> (from);
}
}
for (size_t pos_ = pos_orig; pos_ < pos; ++pos_)
from = static_cast <size_t>
(_follow (from, static_cast <uchar> (key[pos_]), cf));
npos_t moved = pos - pos_orig;
if (tail[pos]) { // remember to move offset to existing tail
const int to_ = _follow (from, static_cast <uchar> (tail[pos]), cf);
_array[to_].base = - static_cast <int> (offset + ++moved);
moved -= 1 + sizeof (value_type); // keep record
}
moved += offset;
for (npos_t i = offset; i <= moved; i += 1 + sizeof (value_type)) {
if (_quota0 == ++*_length0) {
#ifdef USE_EXACT_FIT
_quota0 += *_length0 >= MAX_ALLOC_SIZE ? MAX_ALLOC_SIZE : *_length0;
#else
_quota0 += _quota0;
#endif
_realloc_array (_tail0, _quota0, *_length0);
}
_tail0[*_length0] = static_cast <int> (i);
}
if (pos == len || tail[pos] == '\0') {
const int to = _follow (from, 0, cf); // could be reduced
if (pos == len) return _array[to].value += val; // set value on trie
_array[to].value += *reinterpret_cast <value_type*> (&tail[pos + 1]);
}
from = static_cast <size_t> (_follow (from, static_cast <uchar> (key[pos]), cf));
++pos;
}
const int needed = static_cast <int> (len - pos + 1 + sizeof (value_type));
if (pos == len && *_length0) { // reuse
const int offset0 = _tail0[*_length0];
_tail[offset0] = '\0';
_array[from].base = -offset0;
--*_length0;
return *reinterpret_cast <value_type*> (&_tail[offset0 + 1]) = val;
}
if (_quota < *_length + needed) {
#ifdef USE_EXACT_FIT
_quota += needed > *_length || needed > MAX_ALLOC_SIZE ? needed :
(*_length >= MAX_ALLOC_SIZE ? MAX_ALLOC_SIZE : *_length);
#else
_quota += _quota >= needed ? _quota : needed;
#endif
_realloc_array (_tail, _quota, *_length);
}
_array[from].base = -*_length;
const size_t pos_orig = pos;
char* const tail = &_tail[*_length] - pos;
if (pos < len) {
do tail[pos] = key[pos]; while (++pos < len);
from |= (static_cast <npos_t> (*_length) + (len - pos_orig)) << 32;
}
*_length += needed;
return *reinterpret_cast <value_type*> (&tail[len + 1]) += val;
}
// easy-going erase () without compression
int erase (const char* key) { return erase (key, std::strlen (key)); }
int erase (const char* key, size_t len, npos_t from = 0) {
size_t pos = 0;
const int i = _find (key, from, pos, len);
if (i == CEDAR_NO_PATH || i == CEDAR_NO_VALUE) return -1;
if (from >> 32) from &= TAIL_OFFSET_MASK; // leave tail as is
bool flag = _array[from].base < 0; // have sibling
int e = flag ? static_cast <int> (from) : _array[from].base ^ 0;
from = _array[e].check;
do {
const node& n = _array[from];
flag = _ninfo[n.base ^ _ninfo[from].child].sibling;
if (flag) _pop_sibling (from, n.base, static_cast <uchar> (n.base ^ e));
_push_enode (e);
e = static_cast <int> (from);
from = static_cast <size_t> (_array[from].check);
} while (! flag);
return 0;
}
int build (size_t num, const char** key, const size_t* len = 0, const value_type* val = 0) {
for (size_t i = 0; i < num; ++i)
update (key[i], len ? len[i] : std::strlen (key[i]), val ? val[i] : value_type (i));
return 0;
}
template <typename T>
void dump (T* result, const size_t result_len) {
union { int i; value_type x; } b;
size_t num (0), p (0);
npos_t from = 0;
for (b.i = begin (from, p); b.i != CEDAR_NO_PATH; b.i = next (from, p))
if (num < result_len)
_set_result (&result[num++], b.x, p, from);
else
_err (__FILE__, __LINE__, "dump() needs array of length = num_keys()\n");
}
void shrink_tail () {
union { char* tail; int* length; } t;
const size_t length_
= static_cast <size_t> (*_length)
- static_cast <size_t> (*_length0) * (1 + sizeof (value_type));
t.tail = static_cast <char*> (std::malloc (length_));
if (! t.tail) _err (__FILE__, __LINE__, "memory allocation failed\n");
*t.length = static_cast <int> (sizeof (int));
for (int to = 0; to < _size; ++to) {
node& n = _array[to];
if (n.check >= 0 && _array[n.check].base != to && n.base < 0) {
char* const tail (&t.tail[*t.length]), * const tail_ (&_tail[-n.base]);
n.base = - *t.length;
int i = 0; do tail[i] = tail_[i]; while (tail[i++]);
*reinterpret_cast <value_type*> (&tail[i])
= *reinterpret_cast <const value_type*> (&tail_[i]);
*t.length += i + static_cast <int> (sizeof (value_type));
}
}
std::free (_tail);
_tail = t.tail;
_realloc_array (_tail, *_length, *_length);
_quota = *_length;
_realloc_array (_tail0, 1);
_quota0 = 1;
}
int save (const char* fn, const char* mode, const bool shrink) {
if (shrink) shrink_tail ();
return save (fn, mode);
}
int save (const char* fn, const char* mode = "wb") const {
// _test ();
FILE* fp = std::fopen (fn, mode);
if (! fp) return -1;
std::fwrite (_tail, sizeof (char), static_cast <size_t> (*_length), fp);
std::fwrite (_array, sizeof (node), static_cast <size_t> (_size), fp);
std::fclose (fp);
#ifdef USE_FAST_LOAD
const char* const info
= std::strcat (std::strcpy (new char[std::strlen (fn) + 5], fn), ".sbl");
fp = std::fopen (info, mode);
delete [] info; // resolve memory leak
if (! fp) return -1;
std::fwrite (&_bheadF, sizeof (int), 1, fp);
std::fwrite (&_bheadC, sizeof (int), 1, fp);
std::fwrite (&_bheadO, sizeof (int), 1, fp);
std::fwrite (_ninfo, sizeof (ninfo), static_cast <size_t> (_size), fp);
std::fwrite (_block, sizeof (block), static_cast <size_t> (_size >> 8), fp);
std::fclose (fp);
#endif
return 0;
}
int open (const char* fn, const char* mode = "rb",
const size_t offset = 0, size_t size_ = 0) {
FILE* fp = std::fopen (fn, mode);
if (! fp) return -1;
// get size
if (! size_) {
if (std::fseek (fp, 0, SEEK_END) != 0) return -1;
size_ = static_cast <size_t> (std::ftell (fp));
if (std::fseek (fp, 0, SEEK_SET) != 0) return -1;
}
if (size_ <= offset) return -1;
if (std::fseek (fp, static_cast <long> (offset), SEEK_SET) != 0) return -1;
int len = 0;
if (std::fread (&len, sizeof (int), 1, fp) != 1) return -1;
const size_t length_ = static_cast <size_t> (len);
if (size_ <= offset + length_) return -1;
// set array
clear (false);
size_ = (size_ - offset - length_) / sizeof (node);
_array = static_cast <node*> (std::malloc (sizeof (node) * size_));
_tail = static_cast <char*> (std::malloc (length_));
_tail0 = static_cast <int*> (std::malloc (sizeof (int)));
#ifdef USE_FAST_LOAD
_ninfo = static_cast <ninfo*> (std::malloc (sizeof (ninfo) * size_));
_block = static_cast <block*> (std::malloc (sizeof (block) * size_));
if (! _array || ! _tail || ! _tail0 || ! _ninfo || ! _block)
#else
if (! _array || ! _tail || ! _tail0)
#endif
_err (__FILE__, __LINE__, "memory allocation failed\n");
if (std::fseek (fp, static_cast <long> (offset), SEEK_SET) != 0) return -1;
if (length_ != std::fread (_tail, sizeof (char), length_, fp) ||
size_ != std::fread (_array, sizeof (node), size_, fp))
return -1;
std::fclose (fp);
_size = static_cast <int> (size_);
*_length0 = 0;
#ifdef USE_FAST_LOAD
const char* const info
= std::strcat (std::strcpy (new char[std::strlen (fn) + 5], fn), ".sbl");
fp = std::fopen (info, mode);
delete [] info; // resolve memory leak
if (! fp) return -1;
std::fread (&_bheadF, sizeof (int), 1, fp);
std::fread (&_bheadC, sizeof (int), 1, fp);
std::fread (&_bheadO, sizeof (int), 1, fp);
if (size_ != std::fread (_ninfo, sizeof (ninfo), size_, fp) ||
size_ >> 8 != std::fread (_block, sizeof (block), size_ >> 8, fp))
return -1;
std::fclose (fp);
_capacity = _size;
_quota = *_length;
_quota0 = 1;
#endif
return 0;
}
#ifndef USE_FAST_LOAD
void restore () { // restore information to update
if (! _block) _restore_block ();
if (! _ninfo) _restore_ninfo ();
_capacity = _size;
_quota = *_length;
_quota0 = 1;
}
#endif
void set_array (void* p, size_t size_ = 0) { // ad-hoc
clear (false);
if (size_)
size_ = size_ * unit_size () - static_cast <size_t> (*static_cast <int*> (p));
_tail = static_cast <char*> (p);
_array = reinterpret_cast <node*> (_tail + *_length);
_size = static_cast <int> (size_ / unit_size () + (size_ % unit_size () ? 1 : 0));
_no_delete = true;
}
const void* array () const { return _array; }
void clear (const bool reuse = true) {
if (_no_delete) _array = 0, _tail = 0;
if (_array) std::free (_array);
if (_tail) std::free (_tail);
if (_tail0) std::free (_tail0);
if (_ninfo) std::free (_ninfo);
if (_block) std::free (_block);
_array = 0; _tail = 0; _tail0 = 0; _ninfo = 0; _block = 0;
_bheadF = _bheadC = _bheadO = _capacity = _size = _quota = _quota0 = 0;
if (reuse) _initialize ();
_no_delete = false;
}
// return the first child for a tree rooted by a given node
int begin (npos_t& from, size_t& len) {
#ifndef USE_FAST_LOAD
if (! _ninfo) _restore_ninfo ();
#endif
int base = from >> 32 ? - static_cast <int> (from >> 32) : _array[from].base;
if (base >= 0) { // on trie
uchar c = _ninfo[from].child;
if (! from && ! (c = _ninfo[base ^ c].sibling)) // bug fix
return CEDAR_NO_PATH; // no entry
for (; c && base >= 0; ++len) {
from = static_cast <size_t> (base) ^ c;
base = _array[from].base;
c = _ninfo[from].child;
}
if (base >= 0) return _array[base ^ c].base;
}
const size_t len_ = std::strlen (&_tail[-base]);
from &= TAIL_OFFSET_MASK;
from |= static_cast <npos_t> (static_cast <size_t> (-base) + len_) << 32;
len += len_;
return *reinterpret_cast <int*> (&_tail[-base] + len_ + 1);
}
// return the next child if any
int next (npos_t& from, size_t& len, const npos_t root = 0) {
uchar c = 0;
if (const int offset = static_cast <int> (from >> 32)) { // on tail
if (root >> 32) return CEDAR_NO_PATH;
from &= TAIL_OFFSET_MASK;
len -= static_cast <size_t> (offset - (-_array[from].base));
} else
c = _ninfo[_array[from].base ^ 0].sibling;
for (; ! c && from != root; --len) {
c = _ninfo[from].sibling;
from = static_cast <size_t> (_array[from].check);
}
if (! c) return CEDAR_NO_PATH;
return begin (from = static_cast <size_t> (_array[from].base) ^ c, ++len);
}
npos_t tracking_node[NUM_TRACKING_NODES + 1];
private:
// currently disabled; implement these if you need
da (const da&);
da& operator= (const da&);
node* _array;
union { char* _tail; int* _length; };
union { int* _tail0; int* _length0; };
ninfo* _ninfo;
block* _block;
int _bheadF; // first block of Full; 0
int _bheadC; // first block of Closed; 0 if no Closed
int _bheadO; // first block of Open; 0 if no Open
int _capacity;
int _size;
int _quota;
int _quota0;
int _no_delete;
short _reject[257];
//
static void _err (const char* fn, const int ln, const char* msg)
{ std::fprintf (stderr, "cedar: %s [%d]: %s", fn, ln, msg); std::exit (1); }
template <typename T>
static void _realloc_array (T*& p, const int size_n, const int size_p = 0) {
void* tmp = std::realloc (p, sizeof (T) * static_cast <size_t> (size_n));
if (! tmp)
std::free (p), _err (__FILE__, __LINE__, "memory reallocation failed\n");
p = static_cast <T*> (tmp);
static const T T0 = T ();
for (T* q (p + size_p), * const r (p + size_n); q != r; ++q) *q = T0;
}
void _initialize () { // initilize the first special block
_realloc_array (_array, 256, 256);
_realloc_array (_tail, sizeof (int));
_realloc_array (_tail0, 1);
_realloc_array (_ninfo, 256);
_realloc_array (_block, 1);
_array[0] = node (0, -1);
for (int i = 1; i < 256; ++i)
_array[i] = node (i == 1 ? -255 : - (i - 1), i == 255 ? -1 : - (i + 1));
_capacity = _size = 256;
_block[0].ehead = 1; // bug fix for erase
_quota = *_length = static_cast <int> (sizeof (int));
_quota0 = 1;
for (size_t i = 0 ; i <= NUM_TRACKING_NODES; ++i) tracking_node[i] = 0;
for (short i = 0; i <= 256; ++i) _reject[i] = i + 1;
}
// follow/create edge
template <typename T>
int _follow (npos_t& from, const uchar& label, T& cf) {
int to = 0;
const int base = _array[from].base;
if (base < 0 || _array[to = base ^ label].check < 0) {
to = _pop_enode (base, label, static_cast <int> (from));
_push_sibling (from, to ^ label, label, base >= 0);
} else if (_array[to].check != static_cast <int> (from))
to = _resolve (from, base, label, cf);
return to;
}
// find key from double array
int _find (const char* key, npos_t& from, size_t& pos, const size_t len) const {
npos_t offset = from >> 32;
if (! offset) { // node on trie
for (const uchar* const key_ = reinterpret_cast <const uchar*> (key);
_array[from].base >= 0; ) {
if (pos == len) {
const node& n = _array[_array[from].base ^ 0];
if (n.check != static_cast <int> (from)) return CEDAR_NO_VALUE;
return n.base;
}
size_t to = static_cast <size_t> (_array[from].base); to ^= key_[pos];
if (_array[to].check != static_cast <int> (from)) return CEDAR_NO_PATH;
++pos;
from = to;
}
offset = static_cast <npos_t> (-_array[from].base);
}
// switch to _tail to match suffix
const size_t pos_orig = pos; // start position in reading _tail
const char* const tail = &_tail[offset] - pos;
if (pos < len) {
do if (key[pos] != tail[pos]) break; while (++pos < len);
if (const npos_t moved = pos - pos_orig) {
from &= TAIL_OFFSET_MASK;
from |= (offset + moved) << 32;
}
if (pos < len) return CEDAR_NO_PATH; // input > tail, input != tail
}
if (tail[pos]) return CEDAR_NO_VALUE; // input < tail
return *reinterpret_cast <const int*> (&tail[len + 1]);
}
#ifndef USE_FAST_LOAD
void _restore_ninfo () {
_realloc_array (_ninfo, _size);
for (int to = 0; to < _size; ++to) {
const int from = _array[to].check;
if (from < 0) continue; // skip empty node
const int base = _array[from].base;
if (const uchar label = static_cast <uchar> (base ^ to)) // skip leaf
_push_sibling (static_cast <size_t> (from), base, label,
! from || _ninfo[from].child || _array[base ^ 0].check == from);
}
}
void _restore_block () {
_realloc_array (_block, _size >> 8);
_bheadF = _bheadC = _bheadO = 0;
for (int bi (0), e (0); e < _size; ++bi) { // register blocks to full
block& b = _block[bi];
b.num = 0;
for (; e < (bi << 8) + 256; ++e)
if (_array[e].check < 0 && ++b.num == 1) b.ehead = e;
int& head_out = b.num == 1 ? _bheadC : (b.num == 0 ? _bheadF : _bheadO);
_push_block (bi, head_out, ! head_out && b.num);
}
}
#endif
void _set_result (result_type* x, value_type r, size_t = 0, npos_t = 0) const
{ *x = r; }
void _set_result (result_pair_type* x, value_type r, size_t l, npos_t = 0) const
{ x->value = r; x->length = l; }
void _set_result (result_triple_type* x, value_type r, size_t l, npos_t from) const
{ x->value = r; x->length = l; x->id = from; }
void _pop_block (const int bi, int& head_in, const bool last) {
if (last) { // last one poped; Closed or Open
head_in = 0;
} else {
const block& b = _block[bi];
_block[b.prev].next = b.next;
_block[b.next].prev = b.prev;
if (bi == head_in) head_in = b.next;
}
}
void _push_block (const int bi, int& head_out, const bool empty) {
block& b = _block[bi];
if (empty) { // the destination is empty
head_out = b.prev = b.next = bi;
} else { // use most recently pushed
int& tail_out = _block[head_out].prev;
b.prev = tail_out;
b.next = head_out;
head_out = tail_out = _block[tail_out].next = bi;
}
}
int _add_block () {
if (_size == _capacity) { // allocate memory if needed
#ifdef USE_EXACT_FIT
_capacity += _size >= MAX_ALLOC_SIZE ? MAX_ALLOC_SIZE : _size;
#else
_capacity += _capacity;
#endif
_realloc_array (_array, _capacity, _capacity);
_realloc_array (_ninfo, _capacity, _size);
_realloc_array (_block, _capacity >> 8, _size >> 8);
}
_block[_size >> 8].ehead = _size;
_array[_size] = node (- (_size + 255), - (_size + 1));
for (int i = _size + 1; i < _size + 255; ++i)
_array[i] = node (-(i - 1), -(i + 1));
_array[_size + 255] = node (- (_size + 254), -_size);
_push_block (_size >> 8, _bheadO, ! _bheadO); // append to block Open
_size += 256;
return (_size >> 8) - 1;
}
// transfer block from one start w/ head_in to one start w/ head_out
void _transfer_block (const int bi, int& head_in, int& head_out) {
_pop_block (bi, head_in, bi == _block[bi].next);
_push_block (bi, head_out, ! head_out && _block[bi].num);
}
// pop empty node from block; never transfer the special block (bi = 0)
int _pop_enode (const int base, const uchar label, const int from) {
const int e = base < 0 ? _find_place () : base ^ label;
const int bi = e >> 8;
node& n = _array[e];
block& b = _block[bi];
if (--b.num == 0) {
if (bi) _transfer_block (bi, _bheadC, _bheadF); // Closed to Full
} else { // release empty node from empty ring
_array[-n.base].check = n.check;
_array[-n.check].base = n.base;
if (e == b.ehead) b.ehead = -n.check; // set ehead
if (bi && b.num == 1 && b.trial != MAX_TRIAL) // Open to Closed
_transfer_block (bi, _bheadO, _bheadC);
}
// initialize the released node
if (label) n.base = -1; else n.value = value_type (0);
n.check = from;
if (base < 0) _array[from].base = e ^ label;
return e;
}
// push empty node into empty ring
void _push_enode (const int e) {
const int bi = e >> 8;
block& b = _block[bi];
if (++b.num == 1) { // Full to Closed
b.ehead = e;
_array[e] = node (-e, -e);
if (bi) _transfer_block (bi, _bheadF, _bheadC); // Full to Closed
} else {
const int prev = b.ehead;
const int next = -_array[prev].check;
_array[e] = node (-prev, -next);
_array[prev].check = _array[next].base = -e;
if (b.num == 2 || b.trial == MAX_TRIAL) { // Closed to Open
if (bi) _transfer_block (bi, _bheadC, _bheadO);
}
b.trial = 0;
}
if (b.reject < _reject[b.num]) b.reject = _reject[b.num];
_ninfo[e] = ninfo (); // reset ninfo; no child, no sibling
}
// push label to from's child
void _push_sibling (const npos_t from, const int base, const uchar label, const bool flag = true) {
uchar* c = &_ninfo[from].child;
if (flag && (ORDERED ? label > *c : ! *c))
do c = &_ninfo[base ^ *c].sibling; while (ORDERED && *c && *c < label);
_ninfo[base ^ label].sibling = *c, *c = label;
}
// pop label from from's child
void _pop_sibling (const npos_t from, const int base, const uchar label) {
uchar* c = &_ninfo[from].child;
while (*c != label) c = &_ninfo[base ^ *c].sibling;
*c = _ninfo[base ^ label].sibling;
}
// check whether to replace branching w/ the newly added node
bool _consult (const int base_n, const int base_p, uchar c_n, uchar c_p) const {
do if (! (c_p = _ninfo[base_p ^ c_p].sibling)) return false;
while ((c_n = _ninfo[base_n ^ c_n].sibling));
return true;
}
// enumerate (equal to or more than one) child nodes
uchar* _set_child (uchar* p, const int base, uchar c, const int label = -1) {
--p;
if (! c) { *++p = c; c = _ninfo[base ^ c].sibling; } // 0: terminal
if (ORDERED)
while (c && c < label) { *++p = c; c = _ninfo[base ^ c].sibling; }
if (label != -1) *++p = static_cast <uchar> (label);
while (c) { *++p = c; c = _ninfo[base ^ c].sibling; }
return p;
}
// explore new block to settle down
int _find_place () {
if (_bheadC) return _block[_bheadC].ehead;
if (_bheadO) return _block[_bheadO].ehead;
return _add_block () << 8;
}
int _find_place (const uchar* const first, const uchar* const last) {
if (int bi = _bheadO) {
const int bz = _block[_bheadO].prev;
const short nc = static_cast <short> (last - first + 1);
while (1) { // set candidate block
block& b = _block[bi];
if (b.num >= nc && nc < b.reject) // explore configuration
for (int e = b.ehead;;) {
const int base = e ^ *first;
for (const uchar* p = first; _array[base ^ *++p].check < 0; )
if (p == last) return b.ehead = e; // no conflict
if ((e = -_array[e].check) == b.ehead) break;
}
b.reject = nc;
if (b.reject < _reject[b.num]) _reject[b.num] = b.reject;
const int bi_ = b.next;
if (++b.trial == MAX_TRIAL) _transfer_block (bi, _bheadO, _bheadC);
if (bi == bz) break;
bi = bi_;
}
}
return _add_block () << 8;
}
// resolve conflict on base_n ^ label_n = base_p ^ label_p
template <typename T>
int _resolve (npos_t& from_n, const int base_n, const uchar label_n, T& cf) {
// examine siblings of conflicted nodes
const int to_pn = base_n ^ label_n;
const int from_p = _array[to_pn].check;
const int base_p = _array[from_p].base;
const bool flag // whether to replace siblings of newly added
= _consult (base_n, base_p, _ninfo[from_n].child, _ninfo[from_p].child);
uchar child[256];
uchar* const first = &child[0];
uchar* const last =
flag ? _set_child (first, base_n, _ninfo[from_n].child, label_n)
: _set_child (first, base_p, _ninfo[from_p].child);
const int base =
(first == last ? _find_place () : _find_place (first, last)) ^ *first;
// replace & modify empty list
const int from = flag ? static_cast <int> (from_n) : from_p;
const int base_ = flag ? base_n : base_p;
if (flag && *first == label_n) _ninfo[from].child = label_n; // new child
_array[from].base = base; // new base
for (const uchar* p = first; p <= last; ++p) { // to_ => to
const int to = _pop_enode (base, *p, from);
const int to_ = base_ ^ *p;
_ninfo[to].sibling = (p == last ? 0 : *(p + 1));
if (flag && to_ == to_pn) continue; // skip newcomer (no child)
cf (to_, to);
node& n = _array[to];
node& n_ = _array[to_];
if ((n.base = n_.base) > 0 && *p) { // copy base; bug fix
uchar c = _ninfo[to].child = _ninfo[to_].child;
do _array[n.base ^ c].check = to; // adjust grand son's check
while ((c = _ninfo[n.base ^ c].sibling));
}
if (! flag && to_ == static_cast <int> (from_n)) // parent node moved
from_n = static_cast <size_t> (to); // bug fix
if (! flag && to_ == to_pn) { // the address is immediately used
_push_sibling (from_n, to_pn ^ label_n, label_n);
_ninfo[to_].child = 0; // remember to reset child
if (label_n) n_.base = -1; else n_.value = value_type (0);
n_.check = static_cast <int> (from_n);
} else
_push_enode (to_);
if (NUM_TRACKING_NODES) // keep the traversed node updated
for (size_t j = 0; tracking_node[j] != 0; ++j) {
if (static_cast <int> (tracking_node[j] & TAIL_OFFSET_MASK) == to_) {
tracking_node[j] &= NODE_INDEX_MASK;
tracking_node[j] |= static_cast <npos_t> (to);
}
}
}
return flag ? base ^ label_n : to_pn;
}
// test the validity of double array for debug
void _test (const npos_t from = 0) const {
const int base = _array[from].base;
if (base < 0) { // validate tail offset
assert (*_length >= static_cast <int> (-base + 1 + sizeof (value_type)));
return;
}
uchar c = _ninfo[from].child;
do {
if (from) assert (_array[base ^ c].check == static_cast <int> (from));
if (c) _test (static_cast <npos_t> (base ^ c));
} while ((c = _ninfo[base ^ c].sibling));
}
};
}
#endif