ksycocadict.cpp
/* This file is part of the KDE libraries
* Copyright (C) 1999 Waldo Bastian <bastian@kde.org>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License version 2 as published by the Free Software Foundation;
*
* This library 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
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public License
* along with this library; see the file COPYING.LIB. If not, write to
* the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
* Boston, MA 02110-1301, USA.
**/
#include "ksycocadict.h"
#include "ksycocaentry.h"
#include "ksycoca.h"
#include <qptrlist.h>
#include <qvaluelist.h>
#include <kdebug.h>
#include <stdlib.h>
namespace
{
struct string_entry {
string_entry(QString _key, KSycocaEntry *_payload)
{ keyStr = _key; key = keyStr.unicode(); length = keyStr.length(); payload = _payload; hash = 0; }
uint hash;
int length;
const QChar *key;
QString keyStr;
KSycocaEntry *payload;
};
}
template class QPtrList<string_entry>;
class KSycocaDictStringList : public QPtrList<string_entry>
{
public:
KSycocaDictStringList();
};
KSycocaDictStringList::KSycocaDictStringList()
{
setAutoDelete(true);
}
KSycocaDict::KSycocaDict()
: d(0), mStr(0), mOffset(0)
{
}
KSycocaDict::KSycocaDict(QDataStream *str, int offset)
: d(0), mStr(str), mOffset(offset)
{
Q_UINT32 test1, test2;
str->device()->at(offset);
(*str) >> test1 >> test2;
if ((test1 > 0x000fffff) || (test2 > 1024))
{
KSycoca::flagError();
mHashTableSize = 0;
mOffset = 0;
return;
}
str->device()->at(offset);
(*str) >> mHashTableSize;
(*str) >> mHashList;
mOffset = str->device()->at(); // Start of hashtable
}
KSycocaDict::~KSycocaDict()
{
delete d;
}
void
KSycocaDict::add(const QString &key, KSycocaEntry *payload)
{
if (key.isEmpty()) return; // Not allowed (should never happen)
if (!payload) return; // Not allowed!
if (!d)
{
d = new KSycocaDictStringList();
}
string_entry *entry= new string_entry(key, payload);
d->append(entry);
}
void
KSycocaDict::remove(const QString &key)
{
if (d)
{
for(string_entry *entry=d->first(); entry; entry = d->next())
{
if (entry->keyStr == key)
{
d->remove();
break;
}
}
}
}
int
KSycocaDict::find_string(const QString &key )
{
//kdDebug(7011) << QString("KSycocaDict::find_string(%1)").arg(key) << endl;
if (!mStr || !mOffset)
{
kdError(7011) << "No database available!" << endl;
return 0;
}
if (mHashTableSize == 0)
return 0; // Unlikely to find anything :-]
// Read hash-table data
uint hash = hashKey(key) % mHashTableSize;
//kdDebug(7011) << QString("hash is %1").arg(hash) << endl;
uint off = mOffset+sizeof(Q_INT32)*hash;
//kdDebug(7011) << QString("off is %1").arg(off,8,16) << endl;
mStr->device()->at( off );
Q_INT32 offset;
(*mStr) >> offset;
//kdDebug(7011) << QString("offset is %1").arg(offset,8,16) << endl;
if (offset == 0)
return 0;
if (offset > 0)
return offset; // Positive ID
// Lookup duplicate list.
offset = -offset;
mStr->device()->at(offset);
//kdDebug(7011) << QString("Looking up duplicate list at %1").arg(offset,8,16) << endl;
while(true)
{
(*mStr) >> offset;
if (offset == 0) break;
QString dupkey;
(*mStr) >> dupkey;
//kdDebug(7011) << QString(">> %1 %2").arg(offset,8,16).arg(dupkey) << endl;
if (dupkey == key) return offset;
}
//kdWarning(7011) << "Not found!" << endl;
return 0;
}
uint
KSycocaDict::count()
{
if (!d) return 0;
return d->count();
}
void
KSycocaDict::clear()
{
delete d;
d = 0;
}
uint
KSycocaDict::hashKey( const QString &key)
{
int l = key.length();
register uint h = 0;
for(uint i = 0; i < mHashList.count(); i++)
{
int pos = mHashList[i];
if (pos < 0)
{
pos = -pos-1;
if (pos < l)
h = ((h * 13) + (key[l-pos].cell() % 29)) & 0x3ffffff;
}
else
{
pos = pos-1;
if (pos < l)
h = ((h * 13) + (key[pos].cell() % 29)) & 0x3ffffff;
}
}
return h;
}
//
// Calculate the diversity of the strings at position 'pos'
static int
calcDiversity(KSycocaDictStringList *d, int pos, int sz)
{
if (pos == 0) return 0;
bool *matrix = (bool *) calloc(sz, sizeof(bool));
uint usz = sz;
if (pos < 0)
{
pos = -pos-1;
for(string_entry *entry=d->first(); entry; entry = d->next())
{
register int l = entry->length;
if (pos < l && pos != 0)
{
register uint hash = ((entry->hash * 13) + (entry->key[l-pos].cell() % 29)) & 0x3ffffff;
matrix[ hash % usz ] = true;
}
}
}
else
{
pos = pos-1;
for(string_entry *entry=d->first(); entry; entry = d->next())
{
if (pos < entry->length)
{
register uint hash = ((entry->hash * 13) + (entry->key[pos].cell() % 29)) & 0x3ffffff;
matrix[ hash % usz ] = true;
}
}
}
int diversity = 0;
for(int i=0;i< sz;i++)
if (matrix[i]) diversity++;
free((void *) matrix);
return diversity;
}
//
// Add the diversity of the strings at position 'pos'
static void
addDiversity(KSycocaDictStringList *d, int pos)
{
if (pos == 0) return;
if (pos < 0)
{
pos = -pos-1;
for(string_entry *entry=d->first(); entry; entry = d->next())
{
register int l = entry->length;
if (pos < l)
entry->hash = ((entry->hash * 13) + (entry->key[l-pos].cell() % 29)) & 0x3fffffff;
}
}
else
{
pos = pos - 1;
for(string_entry *entry=d->first(); entry; entry = d->next())
{
if (pos < entry->length)
entry->hash = ((entry->hash * 13) + (entry->key[pos].cell() % 29)) & 0x3fffffff;
}
}
}
void
KSycocaDict::save(QDataStream &str)
{
if (count() == 0)
{
mHashTableSize = 0;
mHashList.clear();
str << mHashTableSize;
str << mHashList;
return;
}
mOffset = str.device()->at();
//kdDebug(7011) << QString("KSycocaDict: %1 entries.").arg(count()) << endl;
//kdDebug(7011) << "Calculating hash keys.." << endl;
int maxLength = 0;
//kdDebug(7011) << "Finding maximum string length" << endl;
for(string_entry *entry=d->first(); entry; entry = d->next())
{
entry->hash = 0;
if (entry->length > maxLength)
maxLength = entry->length;
}
//kdDebug(7011) << QString("Max string length = %1").arg(maxLength) << endl;
// use "almost prime" number for sz (to calculate diversity) and later
// for the table size of big tables
// int sz = d->count()*5-1;
register unsigned int sz = count()*4 + 1;
while(!(((sz % 3) && (sz % 5) && (sz % 7) && (sz % 11) && (sz % 13)))) sz+=2;
int maxDiv = 0;
int maxPos = 0;
int lastDiv = 0;
mHashList.clear();
// try to limit diversity scan by "predicting" positions
// with high diversity
int *oldvec=new int[maxLength*2+1];
for (int i=0; i<(maxLength*2+1); i++) oldvec[i]=0;
int mindiv=0;
while(true)
{
int divsum=0,divnum=0;
maxDiv = 0;
maxPos = 0;
for(int pos=-maxLength; pos <= maxLength; pos++)
{
// cut off
if (oldvec[pos+maxLength]<mindiv)
{ oldvec[pos+maxLength]=0; continue; }
int diversity = calcDiversity(d, pos, sz);
if (diversity > maxDiv)
{
maxDiv = diversity;
maxPos = pos;
}
oldvec[pos+maxLength]=diversity;
divsum+=diversity; divnum++;
}
// arbitrary cut-off value 3/4 of average seems to work
if (divnum)
mindiv=(3*divsum)/(4*divnum);
if (maxDiv <= lastDiv)
break;
// qWarning("Max Div = %d at pos %d", maxDiv, maxPos);
lastDiv = maxDiv;
addDiversity(d, maxPos);
mHashList.append(maxPos);
}
delete [] oldvec;
for(string_entry *entry=d->first(); entry; entry = d->next())
{
entry->hash = hashKey(entry->keyStr);
}
// fprintf(stderr, "Calculating minimum table size..\n");
mHashTableSize = sz;
struct hashtable_entry {
string_entry *entry;
QPtrList<string_entry> *duplicates;
int duplicate_offset;
};
hashtable_entry *hashTable = new hashtable_entry[ sz ];
//kdDebug(7011) << "Clearing hashtable..." << endl;
for (unsigned int i=0; i < sz; i++)
{
hashTable[i].entry = 0;
hashTable[i].duplicates = 0;
}
//kdDebug(7011) << "Filling hashtable..." << endl;
for(string_entry *entry=d->first(); entry; entry = d->next())
{
int hash = entry->hash % sz;
if (!hashTable[hash].entry)
{ // First entry
hashTable[hash].entry = entry;
}
else
{
if (!hashTable[hash].duplicates)
{ // Second entry, build duplicate list.
hashTable[hash].duplicates = new QPtrList<string_entry>();
hashTable[hash].duplicates->append(hashTable[hash].entry);
hashTable[hash].duplicate_offset = 0;
}
hashTable[hash].duplicates->append(entry);
}
}
str << mHashTableSize;
str << mHashList;
mOffset = str.device()->at(); // mOffset points to start of hashTable
//kdDebug(7011) << QString("Start of Hash Table, offset = %1").arg(mOffset,8,16) << endl;
for(int pass = 1; pass <= 2; pass++)
{
str.device()->at(mOffset);
//kdDebug(7011) << QString("Writing hash table (pass #%1)").arg(pass) << endl;
for(uint i=0; i < mHashTableSize; i++)
{
Q_INT32 tmpid;
if (!hashTable[i].entry)
tmpid = (Q_INT32) 0;
else if (!hashTable[i].duplicates)
tmpid = (Q_INT32) hashTable[i].entry->payload->offset(); // Positive ID
else
tmpid = (Q_INT32) -hashTable[i].duplicate_offset; // Negative ID
str << tmpid;
//kdDebug(7011) << QString("Hash table : %1").arg(tmpid,8,16) << endl;
}
//kdDebug(7011) << QString("End of Hash Table, offset = %1").arg(str.device()->at(),8,16) << endl;
//kdDebug(7011) << QString("Writing duplicate lists (pass #%1)").arg(pass) << endl;
for(uint i=0; i < mHashTableSize; i++)
{
if (hashTable[i].duplicates)
{
QPtrList<string_entry> *dups = hashTable[i].duplicates;
hashTable[i].duplicate_offset = str.device()->at();
/*kdDebug(7011) << QString("Duplicate lists: Offset = %1 list_size = %2") .arg(hashTable[i].duplicate_offset,8,16).arg(dups->count()) << endl;
*/
for(string_entry *dup = dups->first(); dup; dup=dups->next())
{
str << (Q_INT32) dup->payload->offset(); // Positive ID
str << dup->keyStr; // Key (QString)
}
str << (Q_INT32) 0; // End of list marker (0)
}
}
//kdDebug(7011) << QString("End of Dict, offset = %1").arg(str.device()->at(),8,16) << endl;
}
//kdDebug(7011) << "Cleaning up hash table." << endl;
for(uint i=0; i < mHashTableSize; i++)
{
delete hashTable[i].duplicates;
}
delete [] hashTable;
}
KGlobal::kdError
kdbgstream kdError(int area=0)
Definition: kdebug.cpp:320
KSycocaEntry
Base class for all Sycoca entries.
Definition: ksycocaentry.h:37
KStdAccel::key
int key(StdAccel id)
Definition: kstdaccel.cpp:383
KGlobal::endl
kdbgstream & endl(kdbgstream &s)
Definition: kdebug.h:430

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