/*
** 2012 April 10
**
** The author disclaims copyright to this source code. In place of
** a legal notice, here is a blessing:
**
** May you do good and not evil.
** May you find forgiveness for yourself and forgive others.
** May you share freely, never taking more than you give.
**
*************************************************************************
**
** This module implements the spellfix1 VIRTUAL TABLE that can be used
** to search a large vocabulary for close matches. See separate
** documentation (http://www.sqlite.org/spellfix1.html) for details.
*/
#include "sqlite3ext.h"
SQLITE_EXTENSION_INIT1
#ifndef SQLITE_AMALGAMATION
# include <string.h>
# include <stdio.h>
# include <stdlib.h>
# include <assert.h>
# define ALWAYS(X) 1
# define NEVER(X) 0
typedef unsigned char u8;
typedef unsigned short u16;
#endif
#include <ctype.h>
#ifndef SQLITE_OMIT_VIRTUALTABLE
/*
** Character classes for ASCII characters:
**
** 0 '' Silent letters: H W
** 1 'A' Any vowel: A E I O U (Y)
** 2 'B' A bilabeal stop or fricative: B F P V W
** 3 'C' Other fricatives or back stops: C G J K Q S X Z
** 4 'D' Alveolar stops: D T
** 5 'H' Letter H at the beginning of a word
** 6 'L' Glide: L
** 7 'R' Semivowel: R
** 8 'M' Nasals: M N
** 9 'Y' Letter Y at the beginning of a word.
** 10 '9' Digits: 0 1 2 3 4 5 6 7 8 9
** 11 ' ' White space
** 12 '?' Other.
*/
#define CCLASS_SILENT 0
#define CCLASS_VOWEL 1
#define CCLASS_B 2
#define CCLASS_C 3
#define CCLASS_D 4
#define CCLASS_H 5
#define CCLASS_L 6
#define CCLASS_R 7
#define CCLASS_M 8
#define CCLASS_Y 9
#define CCLASS_DIGIT 10
#define CCLASS_SPACE 11
#define CCLASS_OTHER 12
/*
** The following table gives the character class for non-initial ASCII
** characters.
*/
static const unsigned char midClass[] = {
/* */ CCLASS_OTHER, /* */ CCLASS_OTHER, /* */ CCLASS_OTHER,
/* */ CCLASS_OTHER, /* */ CCLASS_OTHER, /* */ CCLASS_OTHER,
/* */ CCLASS_OTHER, /* */ CCLASS_OTHER, /* */ CCLASS_OTHER,
/* */ CCLASS_SPACE, /* */ CCLASS_OTHER, /* */ CCLASS_OTHER,
/* */ CCLASS_SPACE, /* */ CCLASS_SPACE, /* */ CCLASS_OTHER,
/* */ CCLASS_OTHER, /* */ CCLASS_OTHER, /* */ CCLASS_OTHER,
/* */ CCLASS_OTHER, /* */ CCLASS_OTHER, /* */ CCLASS_OTHER,
/* */ CCLASS_OTHER, /* */ CCLASS_OTHER, /* */ CCLASS_OTHER,
/* */ CCLASS_OTHER, /* */ CCLASS_OTHER, /* */ CCLASS_OTHER,
/* */ CCLASS_OTHER, /* */ CCLASS_OTHER, /* */ CCLASS_OTHER,
/* */ CCLASS_OTHER, /* */ CCLASS_OTHER, /* */ CCLASS_SPACE,
/* ! */ CCLASS_OTHER, /* " */ CCLASS_OTHER, /* # */ CCLASS_OTHER,
/* $ */ CCLASS_OTHER, /* % */ CCLASS_OTHER, /* & */ CCLASS_OTHER,
/* ' */ CCLASS_SILENT, /* ( */ CCLASS_OTHER, /* ) */ CCLASS_OTHER,
/* * */ CCLASS_OTHER, /* + */ CCLASS_OTHER, /* , */ CCLASS_OTHER,
/* - */ CCLASS_OTHER, /* . */ CCLASS_OTHER, /* / */ CCLASS_OTHER,
/* 0 */ CCLASS_DIGIT, /* 1 */ CCLASS_DIGIT, /* 2 */ CCLASS_DIGIT,
/* 3 */ CCLASS_DIGIT, /* 4 */ CCLASS_DIGIT, /* 5 */ CCLASS_DIGIT,
/* 6 */ CCLASS_DIGIT, /* 7 */ CCLASS_DIGIT, /* 8 */ CCLASS_DIGIT,
/* 9 */ CCLASS_DIGIT, /* : */ CCLASS_OTHER, /* ; */ CCLASS_OTHER,
/* < */ CCLASS_OTHER, /* = */ CCLASS_OTHER, /* > */ CCLASS_OTHER,
/* ? */ CCLASS_OTHER, /* @ */ CCLASS_OTHER, /* A */ CCLASS_VOWEL,
/* B */ CCLASS_B, /* C */ CCLASS_C, /* D */ CCLASS_D,
/* E */ CCLASS_VOWEL, /* F */ CCLASS_B, /* G */ CCLASS_C,
/* H */ CCLASS_SILENT, /* I */ CCLASS_VOWEL, /* J */ CCLASS_C,
/* K */ CCLASS_C, /* L */ CCLASS_L, /* M */ CCLASS_M,
/* N */ CCLASS_M, /* O */ CCLASS_VOWEL, /* P */ CCLASS_B,
/* Q */ CCLASS_C, /* R */ CCLASS_R, /* S */ CCLASS_C,
/* T */ CCLASS_D, /* U */ CCLASS_VOWEL, /* V */ CCLASS_B,
/* W */ CCLASS_B, /* X */ CCLASS_C, /* Y */ CCLASS_VOWEL,
/* Z */ CCLASS_C, /* [ */ CCLASS_OTHER, /* \ */ CCLASS_OTHER,
/* ] */ CCLASS_OTHER, /* ^ */ CCLASS_OTHER, /* _ */ CCLASS_OTHER,
/* ` */ CCLASS_OTHER, /* a */ CCLASS_VOWEL, /* b */ CCLASS_B,
/* c */ CCLASS_C, /* d */ CCLASS_D, /* e */ CCLASS_VOWEL,
/* f */ CCLASS_B, /* g */ CCLASS_C, /* h */ CCLASS_SILENT,
/* i */ CCLASS_VOWEL, /* j */ CCLASS_C, /* k */ CCLASS_C,
/* l */ CCLASS_L, /* m */ CCLASS_M, /* n */ CCLASS_M,
/* o */ CCLASS_VOWEL, /* p */ CCLASS_B, /* q */ CCLASS_C,
/* r */ CCLASS_R, /* s */ CCLASS_C, /* t */ CCLASS_D,
/* u */ CCLASS_VOWEL, /* v */ CCLASS_B, /* w */ CCLASS_B,
/* x */ CCLASS_C, /* y */ CCLASS_VOWEL, /* z */ CCLASS_C,
/* { */ CCLASS_OTHER, /* | */ CCLASS_OTHER, /* } */ CCLASS_OTHER,
/* ~ */ CCLASS_OTHER, /* */ CCLASS_OTHER,
};
/*
** This tables gives the character class for ASCII characters that form the
** initial character of a word. The only difference from midClass is with
** the letters H, W, and Y.
*/
static const unsigned char initClass[] = {
/* */ CCLASS_OTHER, /* */ CCLASS_OTHER, /* */ CCLASS_OTHER,
/* */ CCLASS_OTHER, /* */ CCLASS_OTHER, /* */ CCLASS_OTHER,
/* */ CCLASS_OTHER, /* */ CCLASS_OTHER, /* */ CCLASS_OTHER,
/* */ CCLASS_SPACE, /* */ CCLASS_OTHER, /* */ CCLASS_OTHER,
/* */ CCLASS_SPACE, /* */ CCLASS_SPACE, /* */ CCLASS_OTHER,
/* */ CCLASS_OTHER, /* */ CCLASS_OTHER, /* */ CCLASS_OTHER,
/* */ CCLASS_OTHER, /* */ CCLASS_OTHER, /* */ CCLASS_OTHER,
/* */ CCLASS_OTHER, /* */ CCLASS_OTHER, /* */ CCLASS_OTHER,
/* */ CCLASS_OTHER, /* */ CCLASS_OTHER, /* */ CCLASS_OTHER,
/* */ CCLASS_OTHER, /* */ CCLASS_OTHER, /* */ CCLASS_OTHER,
/* */ CCLASS_OTHER, /* */ CCLASS_OTHER, /* */ CCLASS_SPACE,
/* ! */ CCLASS_OTHER, /* " */ CCLASS_OTHER, /* # */ CCLASS_OTHER,
/* $ */ CCLASS_OTHER, /* % */ CCLASS_OTHER, /* & */ CCLASS_OTHER,
/* ' */ CCLASS_OTHER, /* ( */ CCLASS_OTHER, /* ) */ CCLASS_OTHER,
/* * */ CCLASS_OTHER, /* + */ CCLASS_OTHER, /* , */ CCLASS_OTHER,
/* - */ CCLASS_OTHER, /* . */ CCLASS_OTHER, /* / */ CCLASS_OTHER,
/* 0 */ CCLASS_DIGIT, /* 1 */ CCLASS_DIGIT, /* 2 */ CCLASS_DIGIT,
/* 3 */ CCLASS_DIGIT, /* 4 */ CCLASS_DIGIT, /* 5 */ CCLASS_DIGIT,
/* 6 */ CCLASS_DIGIT, /* 7 */ CCLASS_DIGIT, /* 8 */ CCLASS_DIGIT,
/* 9 */ CCLASS_DIGIT, /* : */ CCLASS_OTHER, /* ; */ CCLASS_OTHER,
/* < */ CCLASS_OTHER, /* = */ CCLASS_OTHER, /* > */ CCLASS_OTHER,
/* ? */ CCLASS_OTHER, /* @ */ CCLASS_OTHER, /* A */ CCLASS_VOWEL,
/* B */ CCLASS_B, /* C */ CCLASS_C, /* D */ CCLASS_D,
/* E */ CCLASS_VOWEL, /* F */ CCLASS_B, /* G */ CCLASS_C,
/* H */ CCLASS_SILENT, /* I */ CCLASS_VOWEL, /* J */ CCLASS_C,
/* K */ CCLASS_C, /* L */ CCLASS_L, /* M */ CCLASS_M,
/* N */ CCLASS_M, /* O */ CCLASS_VOWEL, /* P */ CCLASS_B,
/* Q */ CCLASS_C, /* R */ CCLASS_R, /* S */ CCLASS_C,
/* T */ CCLASS_D, /* U */ CCLASS_VOWEL, /* V */ CCLASS_B,
/* W */ CCLASS_B, /* X */ CCLASS_C, /* Y */ CCLASS_Y,
/* Z */ CCLASS_C, /* [ */ CCLASS_OTHER, /* \ */ CCLASS_OTHER,
/* ] */ CCLASS_OTHER, /* ^ */ CCLASS_OTHER, /* _ */ CCLASS_OTHER,
/* ` */ CCLASS_OTHER, /* a */ CCLASS_VOWEL, /* b */ CCLASS_B,
/* c */ CCLASS_C, /* d */ CCLASS_D, /* e */ CCLASS_VOWEL,
/* f */ CCLASS_B, /* g */ CCLASS_C, /* h */ CCLASS_SILENT,
/* i */ CCLASS_VOWEL, /* j */ CCLASS_C, /* k */ CCLASS_C,
/* l */ CCLASS_L, /* m */ CCLASS_M, /* n */ CCLASS_M,
/* o */ CCLASS_VOWEL, /* p */ CCLASS_B, /* q */ CCLASS_C,
/* r */ CCLASS_R, /* s */ CCLASS_C, /* t */ CCLASS_D,
/* u */ CCLASS_VOWEL, /* v */ CCLASS_B, /* w */ CCLASS_B,
/* x */ CCLASS_C, /* y */ CCLASS_Y, /* z */ CCLASS_C,
/* { */ CCLASS_OTHER, /* | */ CCLASS_OTHER, /* } */ CCLASS_OTHER,
/* ~ */ CCLASS_OTHER, /* */ CCLASS_OTHER,
};
/*
** Mapping from the character class number (0-13) to a symbol for each
** character class. Note that initClass[] can be used to map the class
** symbol back into the class number.
*/
static const unsigned char className[] = ".ABCDHLRMY9 ?";
/*
** Generate a "phonetic hash" from a string of ASCII characters
** in zIn[0..nIn-1].
**
** * Map characters by character class as defined above.
** * Omit double-letters
** * Omit vowels beside R and L
** * Omit T when followed by CH
** * Omit W when followed by R
** * Omit D when followed by J or G
** * Omit K in KN or G in GN at the beginning of a word
**
** Space to hold the result is obtained from sqlite3_malloc()
**
** Return NULL if memory allocation fails.
*/
static unsigned char *phoneticHash(const unsigned char *zIn, int nIn){
unsigned char *zOut = sqlite3_malloc64( nIn + 1 );
int i;
int nOut = 0;
char cPrev = 0x77;
char cPrevX = 0x77;
const unsigned char *aClass = initClass;
if( zOut==0 ) return 0;
if( nIn>2 ){
switch( zIn[0] ){
case 'g':
case 'k': {
if( zIn[1]=='n' ){ zIn++; nIn--; }
break;
}
}
}
for(i=0; i<nIn; i++){
unsigned char c = zIn[i];
if( i+1<nIn ){
if( c=='w' && zIn[i+1]=='r' ) continue;
if( c=='d' && (zIn[i+1]=='j' || zIn[i+1]=='g') ) continue;
if( i+2<nIn ){
if( c=='t' && zIn[i+1]=='c' && zIn[i+2]=='h' ) continue;
}
}
c = aClass[c&0x7f];
if( c==CCLASS_SPACE ) continue;
if( c==CCLASS_OTHER && cPrev!=CCLASS_DIGIT ) continue;
aClass = midClass;
if( c==CCLASS_VOWEL && (cPrevX==CCLASS_R || cPrevX==CCLASS_L) ){
continue; /* No vowels beside L or R */
}
if( (c==CCLASS_R || c==CCLASS_L) && cPrevX==CCLASS_VOWEL ){
nOut--; /* No vowels beside L or R */
}
cPrev = c;
if( c==CCLASS_SILENT ) continue;
cPrevX = c;
c = className[c];
assert( nOut>=0 );
if( nOut==0 || c!=zOut[nOut-1] ) zOut[nOut++] = c;
}
zOut[nOut] = 0;
return zOut;
}
/*
** This is an SQL function wrapper around phoneticHash(). See
** the description of phoneticHash() for additional information.
*/
static void phoneticHashSqlFunc(
sqlite3_context *context,
int argc,
sqlite3_value **argv
){
const unsigned char *zIn;
unsigned char *zOut;
zIn = sqlite3_value_text(argv[0]);
if( zIn==0 ) return;
zOut = phoneticHash(zIn, sqlite3_value_bytes(argv[0]));
if( zOut==0 ){
sqlite3_result_error_nomem(context);
}else{
sqlite3_result_text(context, (char*)zOut, -1, sqlite3_free);
}
}
/*
** Return the character class number for a character given its
** context.
*/
static char characterClass(char cPrev, char c){
return cPrev==0 ? initClass[c&0x7f] : midClass[c&0x7f];
}
/*
** Return the cost of inserting or deleting character c immediately
** following character cPrev. If cPrev==0, that means c is the first
** character of the word.
*/
static int insertOrDeleteCost(char cPrev, char c, char cNext){
char classC = characterClass(cPrev, c);
char classCprev;
if( classC==CCLASS_SILENT ){
/* Insert or delete "silent" characters such as H or W */
return 1;
}
if( cPrev==c ){
/* Repeated characters, or miss a repeat */
return 10;
}
if( classC==CCLASS_VOWEL && (cPrev=='r' || cNext=='r') ){
return 20; /* Insert a vowel before or after 'r' */
}
classCprev = characterClass(cPrev, cPrev);
if( classC==classCprev ){
if( classC==CCLASS_VOWEL ){
/* Remove or add a new vowel to a vowel cluster */
return 15;
}else{
/* Remove or add a consonant not in the same class */
return 50;
}
}
/* any other character insertion or deletion */
return 100;
}
/*
** Divide the insertion cost by this factor when appending to the
** end of the word.
*/
#define FINAL_INS_COST_DIV 4
/*
** Return the cost of substituting cTo in place of cFrom assuming
** the previous character is cPrev. If cPrev==0 then cTo is the first
** character of the word.
*/
static int substituteCost(char cPrev, char cFrom, char cTo){
char classFrom, classTo;
if( cFrom==cTo ){
/* Exact match */
return 0;
}
if( cFrom==(cTo^0x20) && ((cTo>='A' && cTo<='Z') || (cTo>='a' && cTo<='z')) ){
/* differ only in case */
return 0;
}
classFrom = characterClass(cPrev, cFrom);
classTo = characterClass(cPrev, cTo);
if( classFrom==classTo ){
/* Same character class */
return 40;
}
if( classFrom>=CCLASS_B && classFrom<=CCLASS_Y
&& classTo>=CCLASS_B && classTo<=CCLASS_Y ){
/* Convert from one consonant to another, but in a different class */
return 75;
}
/* Any other subsitution */
return 100;
}
/*
** Given two strings zA and zB which are pure ASCII, return the cost
** of transforming zA into zB. If zA ends with '*' assume that it is
** a prefix of zB and give only minimal penalty for extra characters
** on the end of zB.
**
** Smaller numbers mean a closer match.
**
** Negative values indicate an error:
** -1 One of the inputs is NULL
** -2 Non-ASCII characters on input
** -3 Unable to allocate memory
**
** If pnMatch is not NULL, then *pnMatch is set to the number of bytes
** of zB that matched the pattern in zA. If zA does not end with a '*',
** then this value is always the number of bytes in zB (i.e. strlen(zB)).
** If zA does end in a '*', then it is the number of bytes in the prefix
** of zB that was deemed to match zA.
*/
static int editdist1(const char *zA, const char *zB, int *pnMatch){
int nA, nB; /* Number of characters in zA[] and zB[] */
int xA, xB; /* Loop counters for zA[] and zB[] */
char cA = 0, cB; /* Current character of zA and zB */
char cAprev, cBprev; /* Previous character of zA and zB */
char cAnext, cBnext; /* Next character in zA and zB */
int d; /* North-west cost value */
int dc = 0; /* North-west character value */
int res; /* Final result */
int *m; /* The cost matrix */
char *cx; /* Corresponding character values */
int *toFree = 0; /* Malloced space */
int nMatch = 0;
int mStack[60+15]; /* Stack space to use if not too much is needed */
/* Early out if either input is NULL */
if( zA==0 || zB==0 ) return -1;
/* Skip any common prefix */
while( zA[0] && zA[0]==zB[0] ){ dc = zA[0]; zA++; zB++; nMatch++; }
if( pnMatch ) *pnMatch = nMatch;
if( zA[0]==0 && zB[0]==0 ) return 0;
#if 0
printf("A=\"%s\" B=\"%s\" dc=%c\n", zA, zB, dc?dc:' ');
#endif
/* Verify input strings and measure their lengths */
for(nA=0; zA[nA]; nA++){
if( zA[nA]&0x80 ) return -2;
}
for(nB=0; zB[nB]; nB++){
if( zB[nB]&0x80 ) return -2;
}
/* Special processing if either string is empty */
if( nA==0 ){
cBprev = (char)dc;
for(xB=res=0; (cB = zB[xB])!=0; xB++){
res += insertOrDeleteCost(cBprev, cB, zB[xB+1])/FINAL_INS_COST_DIV;
cBprev = cB;
}
return res;
}
if( nB==0 ){
cAprev = (char)dc;
for(xA=res=0; (cA = zA[xA])!=0; xA++){
res += insertOrDeleteCost(cAprev, cA, zA[xA+1]);
cAprev = cA;
}
return res;
}
/* A is a prefix of B */
if( zA[0]=='*' && zA[1]==0 ) return 0;
/* Allocate and initialize the Wagner matrix */
if( nB<(sizeof(mStack)*4)/(sizeof(mStack[0])*5) ){
m = mStack;
}else{
m = toFree = sqlite3_malloc64( (nB+1)*5*sizeof(m[0])/4 );
if( m==0 ) return -3;
}
cx = (char*)&m[nB+1];
/* Compute the Wagner edit distance */
m[0] = 0;
cx[0] = (char)dc;
cBprev = (char)dc;
for(xB=1; xB<=nB; xB++){
cBnext = zB[xB];
cB = zB[xB-1];
cx[xB] = cB;
m[xB] = m[xB-1] + insertOrDeleteCost(cBprev, cB, cBnext);
cBprev = cB;
}
cAprev = (char)dc;
for(xA=1; xA<=nA; xA++){
int lastA = (xA==nA);
cA = zA[xA-1];
cAnext = zA[xA];
if( cA=='*' && lastA ) break;
d = m[0];
dc = cx[0];
m[0] = d + insertOrDeleteCost(cAprev, cA, cAnext);
cBprev = 0;
for(xB=1; xB<=nB; xB++){
int totalCost, insCost, delCost, subCost, ncx;
cB = zB[xB-1];
cBnext = zB[xB];
/* Cost to insert cB */
insCost = insertOrDeleteCost(cx[xB-1], cB, cBnext);
if( lastA ) insCost /= FINAL_INS_COST_DIV;
/* Cost to delete cA */
delCost = insertOrDeleteCost(cx[xB], cA, cBnext);
/* Cost to substitute cA->cB */
subCost = substituteCost(cx[xB-1], cA, cB);
/* Best cost */
totalCost = insCost + m[xB-1];
ncx = cB;
if( (delCost + m[xB])<totalCost ){
totalCost = delCost + m[xB];
ncx = cA;
}
if( (subCost + d)<totalCost ){
totalCost = subCost + d;
}
#if 0
printf("%d,%d d=%4d u=%4d r=%4d dc=%c cA=%c cB=%c"
" ins=%4d del=%4d sub=%4d t=%4d ncx=%c\n",
xA, xB, d, m[xB], m[xB-1], dc?dc:' ', cA, cB,
insCost, delCost, subCost, totalCost, ncx?ncx:' ');
#endif
/* Update the matrix */
d = m[xB];
dc = cx[xB];
m[xB] = totalCost;
cx[xB] = (char)ncx;
cBprev = cB;
}
cAprev = cA;
}
/* Free the wagner matrix and return the result */
if( cA=='*' ){
res = m[1];
for(xB=1; xB<=nB; xB++){
if( m[xB]<res ){
res = m[xB];
if( pnMatch ) *pnMatch = xB+nMatch;
}
}
}else{
res = m[nB];
/* In the current implementation, pnMatch is always NULL if zA does
** not end in "*" */
assert( pnMatch==0 );
}
sqlite3_free(toFree);
return res;
}
/*
** Function: editdist(A,B)
**
** Return the cost of transforming string A into string B. Both strings
** must be pure ASCII text. If A ends with '*' then it is assumed to be
** a prefix of B and extra characters on the end of B have minimal additional
** cost.
*/
static void editdistSqlFunc(
sqlite3_context *context,
int argc,
sqlite3_value **argv
){
int res = editdist1(
(const char*)sqlite3_value_text(argv[0]),
(const char*)sqlite3_value_text(argv[1]),
0);
if( res<0 ){
if( res==(-3) ){
sqlite3_result_error_nomem(context);
}else if( res==(-2) ){
sqlite3_result_error(context, "non-ASCII input to editdist()", -1);
}else{
sqlite3_result_error(context, "NULL input to editdist()", -1);
}
}else{
sqlite3_result_int(context, res);
}
}
/* End of the fixed-cost edit distance implementation
******************************************************************************
*****************************************************************************
** Begin: Configurable cost unicode edit distance routines
*/
/* Forward declaration of structures */
typedef struct EditDist3Cost EditDist3Cost;
typedef struct EditDist3Config EditDist3Config;
typedef struct EditDist3Point EditDist3Point;
typedef struct EditDist3From EditDist3From;
typedef struct EditDist3FromString EditDist3FromString;
typedef struct EditDist3To EditDist3To;
typedef struct EditDist3ToString EditDist3ToString;
typedef struct EditDist3Lang EditDist3Lang;
/*
** An entry in the edit cost table
*/
struct EditDist3Cost {
EditDist3Cost *pNext; /* Next cost element */
u8 nFrom; /* Number of bytes in aFrom */
u8 nTo; /* Number of bytes in aTo */
u16 iCost; /* Cost of this transformation */
char a[4] ; /* FROM string followed by TO string */
/* Additional TO and FROM string bytes appended as necessary */
};
/*
** Edit costs for a particular language ID
*/
struct EditDist3Lang {
int iLang; /* Language ID */
int iInsCost; /* Default insertion cost */
int iDelCost; /* Default deletion cost */
int iSubCost; /* Default substitution cost */
EditDist3Cost *pCost; /* Costs */
};
/*
** The default EditDist3Lang object, with default costs.
*/
static const EditDist3Lang editDist3Lang = { 0, 100, 100, 150, 0 };
/*
** Complete configuration
*/
struct EditDist3Config {
int nLang; /* Number of language IDs. Size of a[] */
EditDist3Lang *a; /* One for each distinct language ID */
};
/*
** Extra information about each character in the FROM string.
*/
struct EditDist3From {
int nSubst; /* Number of substitution cost entries */
int nDel; /* Number of deletion cost entries */
int nByte; /* Number of bytes in this character */
EditDist3Cost **apSubst; /* Array of substitution costs for this element */
EditDist3Cost **apDel; /* Array of deletion cost entries */
};
/*
** A precompiled FROM string.
*
** In the common case we expect the FROM string to be reused multiple times.
** In other words, the common case will be to measure the edit distance
** from a single origin string to multiple target strings.
*/
struct EditDist3FromString {
char *z; /* The complete text of the FROM string */
int n; /* Number of characters in the FROM string */
int isPrefix; /* True if ends with '*' character */
EditDist3From *a; /* Extra info about each char of the FROM string */
};
/*
** Extra information about each character in the TO string.
*/
struct EditDist3To {
int nIns; /* Number of insertion cost entries */
int nByte; /* Number of bytes in this character */
EditDist3Cost **apIns; /* Array of deletion cost entries */
};
/*
** A precompiled FROM string
*/
struct EditDist3ToString {
char *z; /* The complete text of the TO string */
int n; /* Number of characters in the TO string */
EditDist3To *a; /* Extra info about each char of the TO string */
};
/*
** Clear or delete an instance of the object that records all edit-distance
** weights.
*/
static void editDist3ConfigClear(EditDist3Config *p){
int i;
if( p==0 ) return;
for(i=0; i<p->nLang; i++){
EditDist3Cost *pCost, *pNext;
pCost = p->a[i].pCost;
while( pCost ){
pNext = pCost->pNext;
sqlite3_free(pCost);
pCost = pNext;
}
}
sqlite3_free(p->a);
memset(p, 0, sizeof(*p));
}
static void editDist3ConfigDelete(void *pIn){
EditDist3Config *p = (EditDist3Config*)pIn;
editDist3ConfigClear(p);
sqlite3_free(p);
}
/*
** Load all edit-distance weights from a table.
*/
static int editDist3ConfigLoad(
EditDist3Config *p, /* The edit distance configuration to load */
sqlite3 *db, /* Load from this database */
const char *zTable /* Name of the table from which to load */
){
sqlite3_stmt *pStmt;
int rc, rc2;
char *zSql;
int iLangPrev = -9999;
EditDist3Lang *pLang = 0;
zSql = sqlite3_mprintf("SELECT iLang, cFrom, cTo, iCost"
" FROM \"%w\" WHERE iLang>=0 ORDER BY iLang", zTable);
if( zSql==0 ) return SQLITE_NOMEM;
rc = sqlite3_prepare(db, zSql, -1, &pStmt, 0);
sqlite3_free(zSql);
if( rc ) return rc;
editDist3ConfigClear(p);
while( sqlite3_step(pStmt)==SQLITE_ROW ){
int iLang = sqlite3_column_int(pStmt, 0);
const char *zFrom = (const char*)sqlite3_column_text(pStmt, 1);
int nFrom = zFrom ? sqlite3_column_bytes(pStmt, 1) : 0;
const char *zTo = (const char*)sqlite3_column_text(pStmt, 2);
int nTo = zTo ? sqlite3_column_bytes(pStmt, 2) : 0;
int iCost = sqlite3_column_int(pStmt, 3);
assert( zFrom!=0 || nFrom==0 );
assert( zTo!=0 || nTo==0 );
if( nFrom>100 || nTo>100 ) continue;
if( iCost<0 ) continue;
if( pLang==0 || iLang!=iLangPrev ){
EditDist3Lang *pNew;
pNew = sqlite3_realloc64(p->a, (p->nLang+1)*sizeof(p->a[0]));
if( pNew==0 ){ rc = SQLITE_NOMEM; break; }
p->a = pNew;
pLang = &p->a[p->nLang];
p->nLang++;
pLang->iLang = iLang;
pLang->iInsCost = 100;
pLang->iDelCost = 100;
pLang->iSubCost = 150;
pLang->pCost = 0;
iLangPrev = iLang;
}
if( nFrom==1 && zFrom[0]=='?' && nTo==0 ){
pLang->iDelCost = iCost;
}else if( nFrom==0 && nTo==1 && zTo[0]=='?' ){
pLang->iInsCost = iCost;
}else if( nFrom==1 && nTo==1 && zFrom[0]=='?' && zTo[0]=='?' ){
pLang->iSubCost = iCost;
}else{
EditDist3Cost *pCost;
int nExtra = nFrom + nTo - 4;
if( nExtra<0 ) nExtra = 0;
pCost = sqlite3_malloc64( sizeof(*pCost) + nExtra );
if( pCost==0 ){ rc = SQLITE_NOMEM; break; }
pCost->nFrom = (u8)nFrom;
pCost->nTo = (u8)nTo;
pCost->iCost = (u16)iCost;
memcpy(pCost->a, zFrom, nFrom);
memcpy(pCost->a + nFrom, zTo, nTo);
pCost->pNext = pLang->pCost;
pLang->pCost = pCost;
}
}
rc2 = sqlite3_finalize(pStmt);
if( rc==SQLITE_OK ) rc = rc2;
return rc;
}
/*
** Return the length (in bytes) of a utf-8 character. Or return a maximum
** of N.
*/
static int utf8Len(unsigned char c, int N){
int len = 1;
if( c>0x7f ){
if( (c&0xe0)==0xc0 ){
len = 2;
}else if( (c&0xf0)==0xe0 ){
len = 3;
}else{
len = 4;
}
}
if( len>N ) len = N;
return len;
}
/*
** Return TRUE (non-zero) if the To side of the given cost matches
** the given string.
*/
static int matchTo(EditDist3Cost *p, const char *z, int n){
if( p->nTo>n ) return 0;
if( strncmp(p->a+p->nFrom, z, p->nTo)!=0 ) return 0;
return 1;
}
/*
** Return TRUE (non-zero) if the From side of the given cost matches
** the given string.
*/
static int matchFrom(EditDist3Cost *p, const char *z, int n){
assert( p->nFrom<=n );
if( strncmp(p->a, z, p->nFrom)!=0 ) return 0;
return 1;
}
/*
** Return TRUE (non-zero) of the next FROM character and the next TO
** character are the same.
*/
static int matchFromTo(
EditDist3FromString *pStr, /* Left hand string */
int n1, /* Index of comparison character on the left */
const char *z2, /* Right-handl comparison character */
int n2 /* Bytes remaining in z2[] */
){
int b1 = pStr->a[n1].nByte;
if( b1>n2 ) return 0;
if( memcmp(pStr->z+n1, z2, b1)!=0 ) return 0;
return 1;
}
/*
** Delete an EditDist3FromString objecct
*/
static void editDist3FromStringDelete(EditDist3FromString *p){
int i;
if( p ){
for(i=0; i<p->n; i++){
sqlite3_free(p->a[i].apDel);
sqlite3_free(p->a[i].apSubst);
}
sqlite3_free(p);
}
}
/*
** Create a EditDist3FromString object.
*/
static EditDist3FromString *editDist3FromStringNew(
const EditDist3Lang *pLang,
const char *z,
int n
){
EditDist3FromString *pStr;
EditDist3Cost *p;
int i;
if( z==0 ) return 0;
if( n<0 ) n = (int)strlen(z);
pStr = sqlite3_malloc64( sizeof(*pStr) + sizeof(pStr->a[0])*n + n + 1 );
if( pStr==0 ) return 0;
pStr->a = (EditDist3From*)&pStr[1];
memset(pStr->a, 0, sizeof(pStr->a[0])*n);
pStr->n = n;
pStr->z = (char*)&pStr->a[n];
memcpy(pStr->z, z, n+1);
if( n && z[n-1]=='*' ){
pStr->isPrefix = 1;
n--;
pStr->n--;
pStr->z[n] = 0;
}else{
pStr->isPrefix = 0;
}
for(i=0; i<n; i++){
EditDist3From *pFrom = &pStr->a[i];
memset(pFrom, 0, sizeof(*pFrom));
pFrom->nByte = utf8Len((unsigned char)z[i], n-i);
for(p=pLang->pCost; p; p=p->pNext){
EditDist3Cost **apNew;
if( i+p->nFrom>n ) continue;
if( matchFrom(p, z+i, n-i)==0 ) continue;
if( p->nTo==0 ){
apNew = sqlite3_realloc64(pFrom->apDel,
sizeof(*apNew)*(pFrom->nDel+1));
if( apNew==0 ) break;
pFrom->apDel = apNew;
apNew[pFrom->nDel++] = p;
}else{
apNew = sqlite3_realloc64(pFrom->apSubst,
sizeof(*apNew)*(pFrom->nSubst+1));
if( apNew==0 ) break;
pFrom->apSubst = apNew;
apNew[pFrom->nSubst++] = p;
}
}
if( p ){
editDist3FromStringDelete(pStr);
pStr = 0;
break;
}
}
return pStr;
}
/*
** Update entry m[i] such that it is the minimum of its current value
** and m[j]+iCost.
**
** If the iCost is 1,000,000 or greater, then consider the cost to be
** infinite and skip the update.
*/
static void updateCost(
unsigned int *m,
int i,
int j,
int iCost
){
assert( iCost>=0 );
if( iCost<10000 ){
unsigned int b = m[j] + iCost;
if( b<m[i] ) m[i] = b;
}
}
/*
** How much stack space (int bytes) to use for Wagner matrix in
** editDist3Core(). If more space than this is required, the entire
** matrix is taken from the heap. To reduce the load on the memory
** allocator, make this value as large as practical for the
** architecture in use.
*/
#ifndef SQLITE_SPELLFIX_STACKALLOC_SZ
# define SQLITE_SPELLFIX_STACKALLOC_SZ (1024)
#endif
/* Compute the edit distance between two strings.
**
** If an error occurs, return a negative number which is the error code.
**
** If pnMatch is not NULL, then *pnMatch is set to the number of characters
** (not bytes) in z2 that matched the search pattern in *pFrom. If pFrom does
** not contain the pattern for a prefix-search, then this is always the number
** of characters in z2. If pFrom does contain a prefix search pattern, then
** it is the number of characters in the prefix of z2 that was deemed to
** match pFrom.
*/
static int editDist3Core(
EditDist3FromString *pFrom, /* The FROM string */
const char *z2, /* The TO string */
int n2, /* Length of the TO string */
const EditDist3Lang *pLang, /* Edit weights for a particular language ID */
int *pnMatch /* OUT: Characters in matched prefix */
){
int k, n;
int i1, b1;
int i2, b2;
EditDist3FromString f = *pFrom;
EditDist3To *a2;
unsigned int *m;
unsigned int *pToFree;
int szRow;
EditDist3Cost *p;
int res;
sqlite3_uint64 nByte;
unsigned int stackSpace[SQLITE_SPELLFIX_STACKALLOC_SZ/sizeof(unsigned int)];
/* allocate the Wagner matrix and the aTo[] array for the TO string */
n = (f.n+1)*(n2+1);
n = (n+1)&~1;
nByte = n*sizeof(m[0]) + sizeof(a2[0])*n2;
if( nByte<=sizeof(stackSpace) ){
m = stackSpace;
pToFree = 0;
}else{
m = pToFree = sqlite3_malloc64( nByte );
if( m==0 ) return -1; /* Out of memory */
}
a2 = (EditDist3To*)&m[n];
memset(a2, 0, sizeof(a2[0])*n2);
/* Fill in the a1[] matrix for all characters of the TO string */
for(i2=0; i2<n2; i2++){
a2[i2].nByte = utf8Len((unsigned char)z2[i2], n2-i2);
for(p=pLang->pCost; p; p=p->pNext){
EditDist3Cost **apNew;
if( p->nFrom>0 ) continue;
if( i2+p->nTo>n2 ) continue;
if( matchTo(p, z2+i2, n2-i2)==0 ) continue;
a2[i2].nIns++;
apNew = sqlite3_realloc64(a2[i2].apIns, sizeof(*apNew)*a2[i2].nIns);
if( apNew==0 ){
res = -1; /* Out of memory */
goto editDist3Abort;
}
a2[i2].apIns = apNew;
a2[i2].apIns[a2[i2].nIns-1] = p;
}
}
/* Prepare to compute the minimum edit distance */
szRow = f.n+1;
memset(m, 0x01, (n2+1)*szRow*sizeof(m[0]));
m[0] = 0;
/* First fill in the top-row of the matrix with FROM deletion costs */
for(i1=0; i1<f.n; i1 += b1){
b1 = f.a[i1].nByte;
updateCost(m, i1+b1, i1, pLang->iDelCost);
for(k=0; k<f.a[i1].nDel; k++){
p = f.a[i1].apDel[k];
updateCost(m, i1+p->nFrom, i1, p->iCost);
}
}
/* Fill in all subsequent rows, top-to-bottom, left-to-right */
for(i2=0; i2<n2; i2 += b2){
int rx; /* Starting index for current row */
int rxp; /* Starting index for previous row */
b2 = a2[i2].nByte;
rx = szRow*(i2+b2);
rxp = szRow*i2;
updateCost(m, rx, rxp, pLang->iInsCost);
for(k=0; k<a2[i2].nIns; k++){
p = a2[i2].apIns[k];
updateCost(m, szRow*(i2+p->nTo), rxp, p->iCost);
}
for(i1=0; i1<f.n; i1+=b1){
int cx; /* Index of current cell */
int cxp; /* Index of cell immediately to the left */
int cxd; /* Index of cell to the left and one row above */
int cxu; /* Index of cell immediately above */
b1 = f.a[i1].nByte;
cxp = rx + i1;
cx = cxp + b1;
cxd = rxp + i1;
cxu = cxd + b1;
updateCost(m, cx, cxp, pLang->iDelCost);
for(k=0; k<f.a[i1].nDel; k++){
p = f.a[i1].apDel[k];
updateCost(m, cxp+p->nFrom, cxp, p->iCost);
}
updateCost(m, cx, cxu, pLang->iInsCost);
if( matchFromTo(&f, i1, z2+i2, n2-i2) ){
updateCost(m, cx, cxd, 0);
}
updateCost(m, cx, cxd, pLang->iSubCost);
for(k=0; k<f.a[i1].nSubst; k++){
p = f.a[i1].apSubst[k];
if( matchTo(p, z2+i2, n2-i2) ){
updateCost(m, cxd+p->nFrom+szRow*p->nTo, cxd, p->iCost);
}
}
}
}
#if 0 /* Enable for debugging */
printf(" ^");
for(i1=0; i1<f.n; i1++) printf(" %c-%2x", f.z[i1], f.z[i1]&0xff);
printf("\n ^:");
for(i1=0; i1<szRow; i1++){
int v = m[i1];
if( v>9999 ) printf(" ****");
else printf(" %4d", v);
}
printf("\n");
for(i2=0; i2<n2; i2++){
printf("%c-%02x:", z2[i2], z2[i2]&0xff);
for(i1=0; i1<szRow; i1++){
int v = m[(i2+1)*szRow+i1];
if( v>9999 ) printf(" ****");
else printf(" %4d", v);
}
printf("\n");
}
#endif
/* Free memory allocations and return the result */
res = (int)m[szRow*(n2+1)-1];
n = n2;
if( f.isPrefix ){
for(i2=1; i2<=n2; i2++){
int b = m[szRow*i2-1];
if( b<=res ){
res = b;
n = i2 - 1;
}
}
}
if( pnMatch ){
int nExtra = 0;
for(k=0; k<n; k++){
if( (z2[k] & 0xc0)==0x80 ) nExtra++;
}
*pnMatch = n - nExtra;
}
editDist3Abort:
for(i2=0; i2<n2; i2++) sqlite3_free(a2[i2].apIns);
sqlite3_free(pToFree);
return res;
}
/*
** Get an appropriate EditDist3Lang object.
*/
static const EditDist3Lang *editDist3FindLang(
EditDist3Config *pConfig,
int iLang
){
int i;
for(i=0; i<pConfig->nLang; i++){
if( pConfig->a[i].iLang==iLang ) return &pConfig->a[i];
}
return &editDist3Lang;
}
/*
** Function: editdist3(A,B,iLang)
** editdist3(tablename)
**
** Return the cost of transforming string A into string B using edit
** weights for iLang.
**
** The second form loads edit weights into memory from a table.
*/
static void editDist3SqlFunc(
sqlite3_context *context,
int argc,
sqlite3_value **argv
){
EditDist3Config *pConfig = (EditDist3Config*)sqlite3_user_data(context);
sqlite3 *db = sqlite3_context_db_handle(context);
int rc;
if( argc==1 ){
const char *zTable = (const char*)sqlite3_value_text(argv[0]);
rc = editDist3ConfigLoad(pConfig, db, zTable);
if( rc ) sqlite3_result_error_code(context, rc);
}else{
const char *zA = (const char*)sqlite3_value_text(argv[0]);
const char *zB = (const char*)sqlite3_value_text(argv[1]);
int nA = sqlite3_value_bytes(argv[0]);
int nB = sqlite3_value_bytes(argv[1]);
int iLang = argc==3 ? sqlite3_value_int(argv[2]) : 0;
const EditDist3Lang *pLang = editDist3FindLang(pConfig, iLang);
EditDist3FromString *pFrom;
int dist;
pFrom = editDist3FromStringNew(pLang, zA, nA);
if( pFrom==0 ){
sqlite3_result_error_nomem(context);
return;
}
dist = editDist3Core(pFrom, zB, nB, pLang, 0);
editDist3FromStringDelete(pFrom);
if( dist==(-1) ){
sqlite3_result_error_nomem(context);
}else{
sqlite3_result_int(context, dist);
}
}
}
/*
** Register the editDist3 function with SQLite
*/
static int editDist3Install(sqlite3 *db){
int rc;
EditDist3Config *pConfig = sqlite3_malloc64( sizeof(*pConfig) );
if( pConfig==0 ) return SQLITE_NOMEM;
memset(pConfig, 0, sizeof(*pConfig));
rc = sqlite3_create_function_v2(db, "editdist3",
2, SQLITE_UTF8|SQLITE_DETERMINISTIC, pConfig,
editDist3SqlFunc, 0, 0, 0);
if( rc==SQLITE_OK ){
rc = sqlite3_create_function_v2(db, "editdist3",
3, SQLITE_UTF8|SQLITE_DETERMINISTIC, pConfig,
editDist3SqlFunc, 0, 0, 0);
}
if( rc==SQLITE_OK ){
rc = sqlite3_create_function_v2(db, "editdist3",
1, SQLITE_UTF8|SQLITE_DETERMINISTIC, pConfig,
editDist3SqlFunc, 0, 0, editDist3ConfigDelete);
}else{
sqlite3_free(pConfig);
}
return rc;
}
/* End configurable cost unicode edit distance routines
******************************************************************************
******************************************************************************
** Begin transliterate unicode-to-ascii implementation
*/
#if !SQLITE_AMALGAMATION
/*
** This lookup table is used to help decode the first byte of
** a multi-byte UTF8 character.
*/
static const unsigned char sqlite3Utf8Trans1[] = {
0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f,
0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17,
0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f,
0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f,
0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
0x00, 0x01, 0x02, 0x03, 0x00, 0x01, 0x00, 0x00,
};
#endif
/*
** Return the value of the first UTF-8 character in the string.
*/
static int utf8Read(const unsigned char *z, int n, int *pSize){
int c, i;
/* All callers to this routine (in the current implementation)
** always have n>0. */
if( NEVER(n==0) ){
c = i = 0;
}else{
c = z[0];
i = 1;
if( c>=0xc0 ){
c = sqlite3Utf8Trans1[c-0xc0];
while( i<n && (z[i] & 0xc0)==0x80 ){
c = (c<<6) + (0x3f & z[i++]);
}
}
}
*pSize = i;
return c;
}
/*
** Return the number of characters in the utf-8 string in the nIn byte
** buffer pointed to by zIn.
*/
static int utf8Charlen(const char *zIn, int nIn){
int i;
int nChar = 0;
for(i=0; i<nIn; nChar++){
int sz;
utf8Read((const unsigned char *)&zIn[i], nIn-i, &sz);
i += sz;
}
return nChar;
}
/*
** Table of translations from unicode characters into ASCII.
*/
static const struct {
unsigned short int cFrom;
unsigned char cTo0, cTo1;
} translit[] = {
{ 0x00A0, 0x20, 0x00 }, /* to */
{ 0x00B5, 0x75, 0x00 }, /* µ to u */
{ 0x00C0, 0x41, 0x00 }, /* À to A */
{ 0x00C1, 0x41, 0x00 }, /* Á to A */
{ 0x00C2, 0x41, 0x00 }, /* Â to A */
{ 0x00C3, 0x41, 0x00 }, /* Ã to A */
{ 0x00C4, 0x41, 0x65 }, /* Ä to Ae */
{ 0x00C5, 0x41, 0x61 }, /* Å to Aa */
{ 0x00C6, 0x41, 0x45 }, /* Æ to AE */
{ 0x00C7, 0x43, 0x00 }, /* Ç to C */
{ 0x00C8, 0x45, 0x00 }, /* È to E */
{ 0x00C9, 0x45, 0x00 }, /* É to E */
{ 0x00CA, 0x45, 0x00 }, /* Ê to E */
{ 0x00CB, 0x45, 0x00 }, /* Ë to E */
{ 0x00CC, 0x49, 0x00 }, /* Ì to I */
{ 0x00CD, 0x49, 0x00 }, /* Í to I */
{ 0x00CE, 0x49, 0x00 }, /* Î to I */
{ 0x00CF, 0x49, 0x00 }, /* Ï to I */
{ 0x00D0, 0x44, 0x00 }, /* Ð to D */
{ 0x00D1, 0x4E, 0x00 }, /* Ñ to N */
{ 0x00D2, 0x4F, 0x00 }, /* Ò to O */
{ 0x00D3, 0x4F, 0x00 }, /* Ó to O */
{ 0x00D4, 0x4F, 0x00 }, /* Ô to O */
{ 0x00D5, 0x4F, 0x00 }, /* Õ to O */
{ 0x00D6, 0x4F, 0x65 }, /* Ö to Oe */
{ 0x00D7, 0x78, 0x00 }, /* × to x */
{ 0x00D8, 0x4F, 0x00 }, /* Ø to O */
{ 0x00D9, 0x55, 0x00 }, /* Ù to U */
{ 0x00DA, 0x55, 0x00 }, /* Ú to U */
{ 0x00DB, 0x55, 0x00 }, /* Û to U */
{ 0x00DC, 0x55, 0x65 }, /* Ü to Ue */
{ 0x00DD, 0x59, 0x00 }, /* Ý to Y */
{ 0x00DE, 0x54, 0x68 }, /* Þ to Th */
{ 0x00DF, 0x73, 0x73 }, /* ß to ss */
{ 0x00E0, 0x61, 0x00 }, /* à to a */
{ 0x00E1, 0x61, 0x00 }, /* á to a */
{ 0x00E2, 0x61, 0x00 }, /* â to a */
{ 0x00E3, 0x61, 0x00 }, /* ã to a */
{ 0x00E4, 0x61, 0x65 }, /* ä to ae */
{ 0x00E5, 0x61, 0x61 }, /* å to aa */
{ 0x00E6, 0x61, 0x65 }, /* æ to ae */
{ 0x00E7, 0x63, 0x00 }, /* ç to c */
{ 0x00E8, 0x65, 0x00 }, /* è to e */
{ 0x00E9, 0x65, 0x00 }, /* é to e */
{ 0x00EA, 0x65, 0x00 }, /* ê to e */
{ 0x00EB, 0x65, 0x00 }, /* ë to e */
{ 0x00EC, 0x69, 0x00 }, /* ì to i */
{ 0x00ED, 0x69, 0x00 }, /* í to i */
{ 0x00EE, 0x69, 0x00 }, /* î to i */
{ 0x00EF, 0x69, 0x00 }, /* ï to i */
{ 0x00F0, 0x64, 0x00 }, /* ð to d */
{ 0x00F1, 0x6E, 0x00 }, /* ñ to n */
{ 0x00F2, 0x6F, 0x00 }, /* ò to o */
{ 0x00F3, 0x6F, 0x00 }, /* ó to o */
{ 0x00F4, 0x6F, 0x00 }, /* ô to o */
{ 0x00F5, 0x6F, 0x00 }, /* õ to o */
{ 0x00F6, 0x6F, 0x65 }, /* ö to oe */
{ 0x00F7, 0x3A, 0x00 }, /* ÷ to : */
{ 0x00F8, 0x6F, 0x00 }, /* ø to o */
{ 0x00F9, 0x75, 0x00 }, /* ù to u */
{ 0x00FA, 0x75, 0x00 }, /* ú to u */
{ 0x00FB, 0x75, 0x00 }, /* û to u */
{ 0x00FC, 0x75, 0x65 }, /* ü to ue */
{ 0x00FD, 0x79, 0x00 }, /* ý to y */
{ 0x00FE, 0x74, 0x68 }, /* þ to th */
{ 0x00FF, 0x79, 0x00 }, /* ÿ to y */
{ 0x0100, 0x41, 0x00 }, /* Ā to A */
{ 0x0101, 0x61, 0x00 }, /* ā to a */
{ 0x0102, 0x41, 0x00 }, /* Ă to A */
{ 0x0103, 0x61, 0x00 }, /* ă to a */
{ 0x0104, 0x41, 0x00 }, /* Ą to A */
{ 0x0105, 0x61, 0x00 }, /* ą to a */
{ 0x0106, 0x43, 0x00 }, /* Ć to C */
{ 0x0107, 0x63, 0x00 }, /* ć to c */
{ 0x0108, 0x43, 0x68 }, /* Ĉ to Ch */
{ 0x0109, 0x63, 0x68 }, /* ĉ to ch */
{ 0x010A, 0x43, 0x00 }, /* Ċ to C */
{ 0x010B, 0x63, 0x00 }, /* ċ to c */
{ 0x010C, 0x43, 0x00 }, /* Č to C */
{ 0x010D, 0x63, 0x00 }, /* č to c */
{ 0x010E, 0x44, 0x00 }, /* Ď to D */
{ 0x010F, 0x64, 0x00 }, /* ď to d */
{ 0x0110, 0x44, 0x00 }, /* Đ to D */
{ 0x0111, 0x64, 0x00 }, /* đ to d */
{ 0x0112, 0x45, 0x00 }, /* Ē to E */
{ 0x0113, 0x65, 0x00 }, /* ē to e */
{ 0x0114, 0x45, 0x00 }, /* Ĕ to E */
{ 0x0115, 0x65, 0x00 }, /* ĕ to e */
{ 0x0116, 0x45, 0x00 }, /* Ė to E */
{ 0x0117, 0x65, 0x00 }, /* ė to e */
{ 0x0118, 0x45, 0x00 }, /* Ę to E */
{ 0x0119, 0x65, 0x00 }, /* ę to e */
{ 0x011A, 0x45, 0x00 }, /* Ě to E */
{ 0x011B, 0x65, 0x00 }, /* ě to e */
{ 0x011C, 0x47, 0x68 }, /* Ĝ to Gh */
{ 0x011D, 0x67, 0x68 }, /* ĝ to gh */
{ 0x011E, 0x47, 0x00 }, /* Ğ to G */
{ 0x011F, 0x67, 0x00 }, /* ğ to g */
{ 0x0120, 0x47, 0x00 }, /* Ġ to G */
{ 0x0121, 0x67, 0x00 }, /* ġ to g */
{ 0x0122, 0x47, 0x00 }, /* Ģ to G */
{ 0x0123, 0x67, 0x00 }, /* ģ to g */
{ 0x0124, 0x48, 0x68 }, /* Ĥ to Hh */
{ 0x0125, 0x68, 0x68 }, /* ĥ to hh */
{ 0x0126, 0x48, 0x00 }, /* Ħ to H */
{ 0x0127, 0x68, 0x00 }, /* ħ to h */
{ 0x0128, 0x49, 0x00 }, /* Ĩ to I */
{ 0x0129, 0x69, 0x00 }, /* ĩ to i */
{ 0x012A, 0x49, 0x00 }, /* Ī to I */
{ 0x012B, 0x69, 0x00 }, /* ī to i */
{ 0x012C, 0x49, 0x00 }, /* Ĭ to I */
{ 0x012D, 0x69, 0x00 }, /* ĭ to i */
{ 0x012E, 0x49, 0x00 }, /* Į to I */
{ 0x012F, 0x69, 0x00 }, /* į to i */
{ 0x0130, 0x49, 0x00 }, /* İ to I */
{ 0x0131, 0x69, 0x00 }, /* ı to i */
{ 0x0132, 0x49, 0x4A }, /* IJ to IJ */
{ 0x0133, 0x69, 0x6A }, /* ij to ij */
{ 0x0134, 0x4A, 0x68 }, /* Ĵ to Jh */
{ 0x0135, 0x6A, 0x68 }, /* ĵ to jh */
{ 0x0136, 0x4B, 0x00 }, /* Ķ to K */
{ 0x0137, 0x6B, 0x00 }, /* ķ to k */
{ 0x0138, 0x6B, 0x00 }, /* ĸ to k */
{ 0x0139, 0x4C, 0x00 }, /* Ĺ to L */
{ 0x013A, 0x6C, 0x00 }, /* ĺ to l */
{ 0x013B, 0x4C, 0x00 }, /* Ļ to L */
{ 0x013C, 0x6C, 0x00 }, /* ļ to l */
{ 0x013D, 0x4C, 0x00 }, /* Ľ to L */
{ 0x013E, 0x6C, 0x00 }, /* ľ to l */
{ 0x013F, 0x4C, 0x2E }, /* Ŀ to L. */
{ 0x0140, 0x6C, 0x2E }, /* ŀ to l. */
{ 0x0141, 0x4C, 0x00 }, /* Ł to L */
{ 0x0142, 0x6C, 0x00 }, /* ł to l */
{ 0x0143, 0x4E, 0x00 }, /* Ń to N */
{ 0x0144, 0x6E, 0x00 }, /* ń to n */
{ 0x0145, 0x4E, 0x00 }, /* Ņ to N */
{ 0x0146, 0x6E, 0x00 }, /* ņ to n */
{ 0x0147, 0x4E, 0x00 }, /* Ň to N */
{ 0x0148, 0x6E, 0x00 }, /* ň to n */
{ 0x0149, 0x27, 0x6E }, /* ʼn to 'n */
{ 0x014A, 0x4E, 0x47 }, /* Ŋ to NG */
{ 0x014B, 0x6E, 0x67 }, /* ŋ to ng */
{ 0x014C, 0x4F, 0x00 }, /* Ō to O */
{ 0x014D, 0x6F, 0x00 }, /* ō to o */
{ 0x014E, 0x4F, 0x00 }, /* Ŏ to O */
{ 0x014F, 0x6F, 0x00 }, /* ŏ to o */
{ 0x0150, 0x4F, 0x00 }, /* Ő to O */
{ 0x0151, 0x6F, 0x00 }, /* ő to o */
{ 0x0152, 0x4F, 0x45 }, /* Πto OE */
{ 0x0153, 0x6F, 0x65 }, /* œ to oe */
{ 0x0154, 0x52, 0x00 }, /* Ŕ to R */
{ 0x0155, 0x72, 0x00 }, /* ŕ to r */
{ 0x0156, 0x52, 0x00 }, /* Ŗ to R */
{ 0x0157, 0x72, 0x00 }, /* ŗ to r */
{ 0x0158, 0x52, 0x00 }, /* Ř to R */
{ 0x0159, 0x72, 0x00 }, /* ř to r */
{ 0x015A, 0x53, 0x00 }, /* Ś to S */
{ 0x015B, 0x73, 0x00 }, /* ś to s */
{ 0x015C, 0x53, 0x68 }, /* Ŝ to Sh */
{ 0x015D, 0x73, 0x68 }, /* ŝ to sh */
{ 0x015E, 0x53, 0x00 }, /* Ş to S */
{ 0x015F, 0x73, 0x00 }, /* ş to s */
{ 0x0160, 0x53, 0x00 }, /* Š to S */
{ 0x0161, 0x73, 0x00 }, /* š to s */
{ 0x0162, 0x54, 0x00 }, /* Ţ to T */
{ 0x0163, 0x74, 0x00 }, /* ţ to t */
{ 0x0164, 0x54, 0x00 }, /* Ť to T */
{ 0x0165, 0x74, 0x00 }, /* ť to t */
{ 0x0166, 0x54, 0x00 }, /* Ŧ to T */
{ 0x0167, 0x74, 0x00 }, /* ŧ to t */
{ 0x0168, 0x55, 0x00 }, /* Ũ to U */
{ 0x0169, 0x75, 0x00 }, /* ũ to u */
{ 0x016A, 0x55, 0x00 }, /* Ū to U */
{ 0x016B, 0x75, 0x00 }, /* ū to u */
{ 0x016C, 0x55, 0x00 }, /* Ŭ to U */
{ 0x016D, 0x75, 0x00 }, /* ŭ to u */
{ 0x016E, 0x55, 0x00 }, /* Ů to U */
{ 0x016F, 0x75, 0x00 }, /* ů to u */
{ 0x0170, 0x55, 0x00 }, /* Ű to U */
{ 0x0171, 0x75, 0x00 }, /* ű to u */
{ 0x0172, 0x55, 0x00 }, /* Ų to U */
{ 0x0173, 0x75, 0x00 }, /* ų to u */
{ 0x0174, 0x57, 0x00 }, /* Ŵ to W */
{ 0x0175, 0x77, 0x00 }, /* ŵ to w */
{ 0x0176, 0x59, 0x00 }, /* Ŷ to Y */
{ 0x0177, 0x79, 0x00 }, /* ŷ to y */
{ 0x0178, 0x59, 0x00 }, /* Ÿ to Y */
{ 0x0179, 0x5A, 0x00 }, /* Ź to Z */
{ 0x017A, 0x7A, 0x00 }, /* ź to z */
{ 0x017B, 0x5A, 0x00 }, /* Ż to Z */
{ 0x017C, 0x7A, 0x00 }, /* ż to z */
{ 0x017D, 0x5A, 0x00 }, /* Ž to Z */
{ 0x017E, 0x7A, 0x00 }, /* ž to z */
{ 0x017F, 0x73, 0x00 }, /* ſ to s */
{ 0x0192, 0x66, 0x00 }, /* ƒ to f */
{ 0x0218, 0x53, 0x00 }, /* Ș to S */
{ 0x0219, 0x73, 0x00 }, /* ș to s */
{ 0x021A, 0x54, 0x00 }, /* Ț to T */
{ 0x021B, 0x74, 0x00 }, /* ț to t */
{ 0x0386, 0x41, 0x00 }, /* Ά to A */
{ 0x0388, 0x45, 0x00 }, /* Έ to E */
{ 0x0389, 0x49, 0x00 }, /* Ή to I */
{ 0x038A, 0x49, 0x00 }, /* Ί to I */
{ 0x038C, 0x4f, 0x00 }, /* Ό to O */
{ 0x038E, 0x59, 0x00 }, /* Ύ to Y */
{ 0x038F, 0x4f, 0x00 }, /* Ώ to O */
{ 0x0390, 0x69, 0x00 }, /* ΐ to i */
{ 0x0391, 0x41, 0x00 }, /* Α to A */
{ 0x0392, 0x42, 0x00 }, /* Β to B */
{ 0x0393, 0x47, 0x00 }, /* Γ to G */
{ 0x0394, 0x44, 0x00 }, /* Δ to D */
{ 0x0395, 0x45, 0x00 }, /* Ε to E */
{ 0x0396, 0x5a, 0x00 }, /* Ζ to Z */
{ 0x0397, 0x49, 0x00 }, /* Η to I */
{ 0x0398, 0x54, 0x68 }, /* Θ to Th */
{ 0x0399, 0x49, 0x00 }, /* Ι to I */
{ 0x039A, 0x4b, 0x00 }, /* Κ to K */
{ 0x039B, 0x4c, 0x00 }, /* Λ to L */
{ 0x039C, 0x4d, 0x00 }, /* Μ to M */
{ 0x039D, 0x4e, 0x00 }, /* Ν to N */
{ 0x039E, 0x58, 0x00 }, /* Ξ to X */
{ 0x039F, 0x4f, 0x00 }, /* Ο to O */
{ 0x03A0, 0x50, 0x00 }, /* Π to P */
{ 0x03A1, 0x52, 0x00 }, /* Ρ to R */
{ 0x03A3, 0x53, 0x00 }, /* Σ to S */
{ 0x03A4, 0x54, 0x00 }, /* Τ to T */
{ 0x03A5, 0x59, 0x00 }, /* Υ to Y */
{ 0x03A6, 0x46, 0x00 }, /* Φ to F */
{ 0x03A7, 0x43, 0x68 }, /* Χ to Ch */
{ 0x03A8, 0x50, 0x73 }, /* Ψ to Ps */
{ 0x03A9, 0x4f, 0x00 }, /* Ω to O */
{ 0x03AA, 0x49, 0x00 }, /* Ϊ to I */
{ 0x03AB, 0x59, 0x00 }, /* Ϋ to Y */
{ 0x03AC, 0x61, 0x00 }, /* ά to a */
{ 0x03AD, 0x65, 0x00 }, /* έ to e */
{ 0x03AE, 0x69, 0x00 }, /* ή to i */
{ 0x03AF, 0x69, 0x00 }, /* ί to i */
{ 0x03B1, 0x61, 0x00 }, /* α to a */
{ 0x03B2, 0x62, 0x00 }, /* β to b */
{ 0x03B3, 0x67, 0x00 }, /* γ to g */
{ 0x03B4, 0x64, 0x00 }, /* δ to d */
{ 0x03B5, 0x65, 0x00 }, /* ε to e */
{ 0x03B6, 0x7a, 0x00 }, /* ζ to z */
{ 0x03B7, 0x69, 0x00 }, /* η to i */
{ 0x03B8, 0x74, 0x68 }, /* θ to th */
{ 0x03B9, 0x69, 0x00 }, /* ι to i */
{ 0x03BA, 0x6b, 0x00 }, /* κ to k */
{ 0x03BB, 0x6c, 0x00 }, /* λ to l */
{ 0x03BC, 0x6d, 0x00 }, /* μ to m */
{ 0x03BD, 0x6e, 0x00 }, /* ν to n */
{ 0x03BE, 0x78, 0x00 }, /* ξ to x */
{ 0x03BF, 0x6f, 0x00 }, /* ο to o */
{ 0x03C0, 0x70, 0x00 }, /* π to p */
{ 0x03C1, 0x72, 0x00 }, /* ρ to r */
{ 0x03C3, 0x73, 0x00 }, /* σ to s */
{ 0x03C4, 0x74, 0x00 }, /* τ to t */
{ 0x03C5, 0x79, 0x00 }, /* υ to y */
{ 0x03C6, 0x66, 0x00 }, /* φ to f */
{ 0x03C7, 0x63, 0x68 }, /* χ to ch */
{ 0x03C8, 0x70, 0x73 }, /* ψ to ps */
{ 0x03C9, 0x6f, 0x00 }, /* ω to o */
{ 0x03CA, 0x69, 0x00 }, /* ϊ to i */
{ 0x03CB, 0x79, 0x00 }, /* ϋ to y */
{ 0x03CC, 0x6f, 0x00 }, /* ό to o */
{ 0x03CD, 0x79, 0x00 }, /* ύ to y */
{ 0x03CE, 0x69, 0x00 }, /* ώ to i */
{ 0x0400, 0x45, 0x00 }, /* Ѐ to E */
{ 0x0401, 0x45, 0x00 }, /* Ё to E */
{ 0x0402, 0x44, 0x00 }, /* Ђ to D */
{ 0x0403, 0x47, 0x00 }, /* Ѓ to G */
{ 0x0404, 0x45, 0x00 }, /* Є to E */
{ 0x0405, 0x5a, 0x00 }, /* Ѕ to Z */
{ 0x0406, 0x49, 0x00 }, /* І to I */
{ 0x0407, 0x49, 0x00 }, /* Ї to I */
{ 0x0408, 0x4a, 0x00 }, /* Ј to J */
{ 0x0409, 0x49, 0x00 }, /* Љ to I */
{ 0x040A, 0x4e, 0x00 }, /* Њ to N */
{ 0x040B, 0x44, 0x00 }, /* Ћ to D */
{ 0x040C, 0x4b, 0x00 }, /* Ќ to K */
{ 0x040D, 0x49, 0x00 }, /* Ѝ to I */
{ 0x040E, 0x55, 0x00 }, /* Ў to U */
{ 0x040F, 0x44, 0x00 }, /* Џ to D */
{ 0x0410, 0x41, 0x00 }, /* А to A */
{ 0x0411, 0x42, 0x00 }, /* Б to B */
{ 0x0412, 0x56, 0x00 }, /* В to V */
{ 0x0413, 0x47, 0x00 }, /* Г to G */
{ 0x0414, 0x44, 0x00 }, /* Д to D */
{ 0x0415, 0x45, 0x00 }, /* Е to E */
{ 0x0416, 0x5a, 0x68 }, /* Ж to Zh */
{ 0x0417, 0x5a, 0x00 }, /* З to Z */
{ 0x0418, 0x49, 0x00 }, /* И to I */
{ 0x0419, 0x49, 0x00 }, /* Й to I */
{ 0x041A, 0x4b, 0x00 }, /* К to K */
{ 0x041B, 0x4c, 0x00 }, /* Л to L */
{ 0x041C, 0x4d, 0x00 }, /* М to M */
{ 0x041D, 0x4e, 0x00 }, /* Н to N */
{ 0x041E, 0x4f, 0x00 }, /* О to O */
{ 0x041F, 0x50, 0x00 }, /* П to P */
{ 0x0420, 0x52, 0x00 }, /* Р to R */
{ 0x0421, 0x53, 0x00 }, /* С to S */
{ 0x0422, 0x54, 0x00 }, /* Т to T */
{ 0x0423, 0x55, 0x00 }, /* У to U */
{ 0x0424, 0x46, 0x00 }, /* Ф to F */
{ 0x0425, 0x4b, 0x68 }, /* Х to Kh */
{ 0x0426, 0x54, 0x63 }, /* Ц to Tc */
{ 0x0427, 0x43, 0x68 }, /* Ч to Ch */
{ 0x0428, 0x53, 0x68 }, /* Ш to Sh */
{ 0x0429, 0x53, 0x68 }, /* Щ to Shch */
{ 0x042A, 0x61, 0x00 }, /* to A */
{ 0x042B, 0x59, 0x00 }, /* Ы to Y */
{ 0x042C, 0x59, 0x00 }, /* to Y */
{ 0x042D, 0x45, 0x00 }, /* Э to E */
{ 0x042E, 0x49, 0x75 }, /* Ю to Iu */
{ 0x042F, 0x49, 0x61 }, /* Я to Ia */
{ 0x0430, 0x61, 0x00 }, /* а to a */
{ 0x0431, 0x62, 0x00 }, /* б to b */
{ 0x0432, 0x76, 0x00 }, /* в to v */
{ 0x0433, 0x67, 0x00 }, /* г to g */
{ 0x0434, 0x64, 0x00 }, /* д to d */
{ 0x0435, 0x65, 0x00 }, /* е to e */
{ 0x0436, 0x7a, 0x68 }, /* ж to zh */
{ 0x0437, 0x7a, 0x00 }, /* з to z */
{ 0x0438, 0x69, 0x00 }, /* и to i */
{ 0x0439, 0x69, 0x00 }, /* й to i */
{ 0x043A, 0x6b, 0x00 }, /* к to k */
{ 0x043B, 0x6c, 0x00 }, /* л to l */
{ 0x043C, 0x6d, 0x00 }, /* м to m */
{ 0x043D, 0x6e, 0x00 }, /* н to n */
{ 0x043E, 0x6f, 0x00 }, /* о to o */
{ 0x043F, 0x70, 0x00 }, /* п to p */
{ 0x0440, 0x72, 0x00 }, /* р to r */
{ 0x0441, 0x73, 0x00 }, /* с to s */
{ 0x0442, 0x74, 0x00 }, /* т to t */
{ 0x0443, 0x75, 0x00 }, /* у to u */
{ 0x0444, 0x66, 0x00 }, /* ф to f */
{ 0x0445, 0x6b, 0x68 }, /* х to kh */
{ 0x0446, 0x74, 0x63 }, /* ц to tc */
{ 0x0447, 0x63, 0x68 }, /* ч to ch */
{ 0x0448, 0x73, 0x68 }, /* ш to sh */
{ 0x0449, 0x73, 0x68 }, /* щ to shch */
{ 0x044A, 0x61, 0x00 }, /* to a */
{ 0x044B, 0x79, 0x00 }, /* ы to y */
{ 0x044C, 0x79, 0x00 }, /* to y */
{ 0x044D, 0x65, 0x00 }, /* э to e */
{ 0x044E, 0x69, 0x75 }, /* ю to iu */
{ 0x044F, 0x69, 0x61 }, /* я to ia */
{ 0x0450, 0x65, 0x00 }, /* ѐ to e */
{ 0x0451, 0x65, 0x00 }, /* ё to e */
{ 0x0452, 0x64, 0x00 }, /* ђ to d */
{ 0x0453, 0x67, 0x00 }, /* ѓ to g */
{ 0x0454, 0x65, 0x00 }, /* є to e */
{ 0x0455, 0x7a, 0x00 }, /* ѕ to z */
{ 0x0456, 0x69, 0x00 }, /* і to i */
{ 0x0457, 0x69, 0x00 }, /* ї to i */
{ 0x0458, 0x6a, 0x00 }, /* ј to j */
{ 0x0459, 0x69, 0x00 }, /* љ to i */
{ 0x045A, 0x6e, 0x00 }, /* њ to n */
{ 0x045B, 0x64, 0x00 }, /* ћ to d */
{ 0x045C, 0x6b, 0x00 }, /* ќ to k */
{ 0x045D, 0x69, 0x00 }, /* ѝ to i */
{ 0x045E, 0x75, 0x00 }, /* ў to u */
{ 0x045F, 0x64, 0x00 }, /* џ to d */
{ 0x1E02, 0x42, 0x00 }, /* Ḃ to B */
{ 0x1E03, 0x62, 0x00 }, /* ḃ to b */
{ 0x1E0A, 0x44, 0x00 }, /* Ḋ to D */
{ 0x1E0B, 0x64, 0x00 }, /* ḋ to d */
{ 0x1E1E, 0x46, 0x00 }, /* Ḟ to F */
{ 0x1E1F, 0x66, 0x00 }, /* ḟ to f */
{ 0x1E40, 0x4D, 0x00 }, /* Ṁ to M */
{ 0x1E41, 0x6D, 0x00 }, /* ṁ to m */
{ 0x1E56, 0x50, 0x00 }, /* Ṗ to P */
{ 0x1E57, 0x70, 0x00 }, /* ṗ to p */
{ 0x1E60, 0x53, 0x00 }, /* Ṡ to S */
{ 0x1E61, 0x73, 0x00 }, /* ṡ to s */
{ 0x1E6A, 0x54, 0x00 }, /* Ṫ to T */
{ 0x1E6B, 0x74, 0x00 }, /* ṫ to t */
{ 0x1E80, 0x57, 0x00 }, /* Ẁ to W */
{ 0x1E81, 0x77, 0x00 }, /* ẁ to w */
{ 0x1E82, 0x57, 0x00 }, /* Ẃ to W */
{ 0x1E83, 0x77, 0x00 }, /* ẃ to w */
{ 0x1E84, 0x57, 0x00 }, /* Ẅ to W */
{ 0x1E85, 0x77, 0x00 }, /* ẅ to w */
{ 0x1EF2, 0x59, 0x00 }, /* Ỳ to Y */
{ 0x1EF3, 0x79, 0x00 }, /* ỳ to y */
{ 0xFB00, 0x66, 0x66 }, /* ff to ff */
{ 0xFB01, 0x66, 0x69 }, /* fi to fi */
{ 0xFB02, 0x66, 0x6C }, /* fl to fl */
{ 0xFB05, 0x73, 0x74 }, /* ſt to st */
{ 0xFB06, 0x73, 0x74 }, /* st to st */
};
/*
** Convert the input string from UTF-8 into pure ASCII by converting
** all non-ASCII characters to some combination of characters in the
** ASCII subset.
**
** The returned string might contain more characters than the input.
**
** Space to hold the returned string comes from sqlite3_malloc() and
** should be freed by the caller.
*/
static unsigned char *transliterate(const unsigned char *zIn, int nIn){
unsigned char *zOut = sqlite3_malloc64( nIn*4 + 1 );
int c, sz, nOut;
if( zOut==0 ) return 0;
nOut = 0;
while( nIn>0 ){
c = utf8Read(zIn, nIn, &sz);
zIn += sz;
nIn -= sz;
if( c<=127 ){
zOut[nOut++] = (unsigned char)c;
}else{
int xTop, xBtm, x;
xTop = sizeof(translit)/sizeof(translit[0]) - 1;
xBtm = 0;
while( xTop>=xBtm ){
x = (xTop + xBtm)/2;
if( translit[x].cFrom==c ){
zOut[nOut++] = translit[x].cTo0;
if( translit[x].cTo1 ){
zOut[nOut++] = translit[x].cTo1;
/* Add an extra "ch" after the "sh" for Щ and щ */
if( c==0x0429 || c== 0x0449 ){
zOut[nOut++] = 'c';
zOut[nOut++] = 'h';
}
}
c = 0;
break;
}else if( translit[x].cFrom>c ){
xTop = x-1;
}else{
xBtm = x+1;
}
}
if( c ) zOut[nOut++] = '?';
}
}
zOut[nOut] = 0;
return zOut;
}
/*
** Return the number of characters in the shortest prefix of the input
** string that transliterates to an ASCII string nTrans bytes or longer.
** Or, if the transliteration of the input string is less than nTrans
** bytes in size, return the number of characters in the input string.
*/
static int translen_to_charlen(const char *zIn, int nIn, int nTrans){
int i, c, sz, nOut;
int nChar;
i = nOut = 0;
for(nChar=0; i<nIn && nOut<nTrans; nChar++){
c = utf8Read((const unsigned char *)&zIn[i], nIn-i, &sz);
i += sz;
nOut++;
if( c>=128 ){
int xTop, xBtm, x;
xTop = sizeof(translit)/sizeof(translit[0]) - 1;
xBtm = 0;
while( xTop>=xBtm ){
x = (xTop + xBtm)/2;
if( translit[x].cFrom==c ){
if( translit[x].cTo1 ) nOut++;
if( c==0x0429 || c== 0x0449 ) nOut += 2;
break;
}else if( translit[x].cFrom>c ){
xTop = x-1;
}else{
xBtm = x+1;
}
}
}
}
return nChar;
}
/*
** spellfix1_translit(X)
**
** Convert a string that contains non-ASCII Roman characters into
** pure ASCII.
*/
static void transliterateSqlFunc(
sqlite3_context *context,
int argc,
sqlite3_value **argv
){
const unsigned char *zIn = sqlite3_value_text(argv[0]);
int nIn = sqlite3_value_bytes(argv[0]);
unsigned char *zOut = transliterate(zIn, nIn);
if( zOut==0 ){
sqlite3_result_error_nomem(context);
}else{
sqlite3_result_text(context, (char*)zOut, -1, sqlite3_free);
}
}
/*
** spellfix1_scriptcode(X)
**
** Try to determine the dominant script used by the word X and return
** its ISO 15924 numeric code.
**
** The current implementation only understands the following scripts:
**
** 215 (Latin)
** 220 (Cyrillic)
** 200 (Greek)
**
** This routine will return 998 if the input X contains characters from
** two or more of the above scripts or 999 if X contains no characters
** from any of the above scripts.
*/
static void scriptCodeSqlFunc(
sqlite3_context *context,
int argc,
sqlite3_value **argv
){
const unsigned char *zIn = sqlite3_value_text(argv[0]);
int nIn = sqlite3_value_bytes(argv[0]);
int c, sz;
int scriptMask = 0;
int res;
int seenDigit = 0;
# define SCRIPT_LATIN 0x0001
# define SCRIPT_CYRILLIC 0x0002
# define SCRIPT_GREEK 0x0004
# define SCRIPT_HEBREW 0x0008
# define SCRIPT_ARABIC 0x0010
while( nIn>0 ){
c = utf8Read(zIn, nIn, &sz);
zIn += sz;
nIn -= sz;
if( c<0x02af ){
if( c>=0x80 || midClass[c&0x7f]<CCLASS_DIGIT ){
scriptMask |= SCRIPT_LATIN;
}else if( c>='0' && c<='9' ){
seenDigit = 1;
}
}else if( c>=0x0400 && c<=0x04ff ){
scriptMask |= SCRIPT_CYRILLIC;
}else if( c>=0x0386 && c<=0x03ce ){
scriptMask |= SCRIPT_GREEK;
}else if( c>=0x0590 && c<=0x05ff ){
scriptMask |= SCRIPT_HEBREW;
}else if( c>=0x0600 && c<=0x06ff ){
scriptMask |= SCRIPT_ARABIC;
}
}
if( scriptMask==0 && seenDigit ) scriptMask = SCRIPT_LATIN;
switch( scriptMask ){
case 0: res = 999; break;
case SCRIPT_LATIN: res = 215; break;
case SCRIPT_CYRILLIC: res = 220; break;
case SCRIPT_GREEK: res = 200; break;
case SCRIPT_HEBREW: res = 125; break;
case SCRIPT_ARABIC: res = 160; break;
default: res = 998; break;
}
sqlite3_result_int(context, res);
}
/* End transliterate
******************************************************************************
******************************************************************************
** Begin spellfix1 virtual table.
*/
/* Maximum length of a phonehash used for querying the shadow table */
#define SPELLFIX_MX_HASH 32
/* Maximum number of hash strings to examine per query */
#define SPELLFIX_MX_RUN 1
typedef struct spellfix1_vtab spellfix1_vtab;
typedef struct spellfix1_cursor spellfix1_cursor;
/* Fuzzy-search virtual table object */
struct spellfix1_vtab {
sqlite3_vtab base; /* Base class - must be first */
sqlite3 *db; /* Database connection */
char *zDbName; /* Name of database holding this table */
char *zTableName; /* Name of the virtual table */
char *zCostTable; /* Table holding edit-distance cost numbers */
EditDist3Config *pConfig3; /* Parsed edit distance costs */
};
/* Fuzzy-search cursor object */
struct spellfix1_cursor {
sqlite3_vtab_cursor base; /* Base class - must be first */
spellfix1_vtab *pVTab; /* The table to which this cursor belongs */
char *zPattern; /* rhs of MATCH clause */
int idxNum; /* idxNum value passed to xFilter() */
int nRow; /* Number of rows of content */
int nAlloc; /* Number of allocated rows */
int iRow; /* Current row of content */
int iLang; /* Value of the langid= constraint */
int iTop; /* Value of the top= constraint */
int iScope; /* Value of the scope= constraint */
int nSearch; /* Number of vocabulary items checked */
sqlite3_stmt *pFullScan; /* Shadow query for a full table scan */
struct spellfix1_row { /* For each row of content */
sqlite3_int64 iRowid; /* Rowid for this row */
char *zWord; /* Text for this row */
int iRank; /* Rank for this row */
int iDistance; /* Distance from pattern for this row */
int iScore; /* Score for sorting */
int iMatchlen; /* Value of matchlen column (or -1) */
char zHash[SPELLFIX_MX_HASH]; /* the phonehash used for this match */
} *a;
};
/*
** Construct one or more SQL statements from the format string given
** and then evaluate those statements. The success code is written
** into *pRc.
**
** If *pRc is initially non-zero then this routine is a no-op.
*/
static void spellfix1DbExec(
int *pRc, /* Success code */
sqlite3 *db, /* Database in which to run SQL */
const char *zFormat, /* Format string for SQL */
... /* Arguments to the format string */
){
va_list ap;
char *zSql;
if( *pRc ) return;
va_start(ap, zFormat);
zSql = sqlite3_vmprintf(zFormat, ap);
va_end(ap);
if( zSql==0 ){
*pRc = SQLITE_NOMEM;
}else{
*pRc = sqlite3_exec(db, zSql, 0, 0, 0);
sqlite3_free(zSql);
}
}
/*
** xDisconnect/xDestroy method for the fuzzy-search module.
*/
static int spellfix1Uninit(int isDestroy, sqlite3_vtab *pVTab){
spellfix1_vtab *p = (spellfix1_vtab*)pVTab;
int rc = SQLITE_OK;
if( isDestroy ){
sqlite3 *db = p->db;
spellfix1DbExec(&rc, db, "DROP TABLE IF EXISTS \"%w\".\"%w_vocab\"",
p->zDbName, p->zTableName);
}
if( rc==SQLITE_OK ){
sqlite3_free(p->zTableName);
editDist3ConfigDelete(p->pConfig3);
sqlite3_free(p->zCostTable);
sqlite3_free(p);
}
return rc;
}
static int spellfix1Disconnect(sqlite3_vtab *pVTab){
return spellfix1Uninit(0, pVTab);
}
static int spellfix1Destroy(sqlite3_vtab *pVTab){
return spellfix1Uninit(1, pVTab);
}
/*
** Make a copy of a string. Remove leading and trailing whitespace
** and dequote it.
*/
static char *spellfix1Dequote(const char *zIn){
char *zOut;
int i, j;
char c;
while( isspace((unsigned char)zIn[0]) ) zIn++;
zOut = sqlite3_mprintf("%s", zIn);
if( zOut==0 ) return 0;
i = (int)strlen(zOut);
#if 0 /* The parser will never leave spaces at the end */
while( i>0 && isspace(zOut[i-1]) ){ i--; }
#endif
zOut[i] = 0;
c = zOut[0];
if( c=='\'' || c=='"' ){
for(i=1, j=0; ALWAYS(zOut[i]); i++){
zOut[j++] = zOut[i];
if( zOut[i]==c ){
if( zOut[i+1]==c ){
i++;
}else{
zOut[j-1] = 0;
break;
}
}
}
}
return zOut;
}
/*
** xConnect/xCreate method for the spellfix1 module. Arguments are:
**
** argv[0] -> module name ("spellfix1")
** argv[1] -> database name
** argv[2] -> table name
** argv[3].. -> optional arguments (i.e. "edit_cost_table" parameter)
*/
static int spellfix1Init(
int isCreate,
sqlite3 *db,
void *pAux,
int argc, const char *const*argv,
sqlite3_vtab **ppVTab,
char **pzErr
){
spellfix1_vtab *pNew = 0;
/* const char *zModule = argv[0]; // not used */
const char *zDbName = argv[1];
const char *zTableName = argv[2];
int nDbName;
int rc = SQLITE_OK;
int i;
nDbName = (int)strlen(zDbName);
pNew = sqlite3_malloc64( sizeof(*pNew) + nDbName + 1);
if( pNew==0 ){
rc = SQLITE_NOMEM;
}else{
memset(pNew, 0, sizeof(*pNew));
pNew->zDbName = (char*)&pNew[1];
memcpy(pNew->zDbName, zDbName, nDbName+1);
pNew->zTableName = sqlite3_mprintf("%s", zTableName);
pNew->db = db;
if( pNew->zTableName==0 ){
rc = SQLITE_NOMEM;
}else{
rc = sqlite3_declare_vtab(db,
"CREATE TABLE x(word,rank,distance,langid, "
"score, matchlen, phonehash HIDDEN, "
"top HIDDEN, scope HIDDEN, srchcnt HIDDEN, "
"soundslike HIDDEN, command HIDDEN)"
);
#define SPELLFIX_COL_WORD 0
#define SPELLFIX_COL_RANK 1
#define SPELLFIX_COL_DISTANCE 2
#define SPELLFIX_COL_LANGID 3
#define SPELLFIX_COL_SCORE 4
#define SPELLFIX_COL_MATCHLEN 5
#define SPELLFIX_COL_PHONEHASH 6
#define SPELLFIX_COL_TOP 7
#define SPELLFIX_COL_SCOPE 8
#define SPELLFIX_COL_SRCHCNT 9
#define SPELLFIX_COL_SOUNDSLIKE 10
#define SPELLFIX_COL_COMMAND 11
}
if( rc==SQLITE_OK && isCreate ){
spellfix1DbExec(&rc, db,
"CREATE TABLE IF NOT EXISTS \"%w\".\"%w_vocab\"(\n"
" id INTEGER PRIMARY KEY,\n"
" rank INT,\n"
" langid INT,\n"
" word TEXT,\n"
" k1 TEXT,\n"
" k2 TEXT\n"
");\n",
zDbName, zTableName
);
spellfix1DbExec(&rc, db,
"CREATE INDEX IF NOT EXISTS \"%w\".\"%w_vocab_index_langid_k2\" "
"ON \"%w_vocab\"(langid,k2);",
zDbName, zTableName, zTableName
);
}
for(i=3; rc==SQLITE_OK && i<argc; i++){
if( strncmp(argv[i],"edit_cost_table=",16)==0 && pNew->zCostTable==0 ){
pNew->zCostTable = spellfix1Dequote(&argv[i][16]);
if( pNew->zCostTable==0 ) rc = SQLITE_NOMEM;
continue;
}
*pzErr = sqlite3_mprintf("bad argument to spellfix1(): \"%s\"", argv[i]);
rc = SQLITE_ERROR;
}
}
if( rc && pNew ){
*ppVTab = 0;
spellfix1Uninit(0, &pNew->base);
}else{
*ppVTab = (sqlite3_vtab *)pNew;
}
return rc;
}
/*
** The xConnect and xCreate methods
*/
static int spellfix1Connect(
sqlite3 *db,
void *pAux,
int argc, const char *const*argv,
sqlite3_vtab **ppVTab,
char **pzErr
){
return spellfix1Init(0, db, pAux, argc, argv, ppVTab, pzErr);
}
static int spellfix1Create(
sqlite3 *db,
void *pAux,
int argc, const char *const*argv,
sqlite3_vtab **ppVTab,
char **pzErr
){
return spellfix1Init(1, db, pAux, argc, argv, ppVTab, pzErr);
}
/*
** Clear all of the content from a cursor.
*/
static void spellfix1ResetCursor(spellfix1_cursor *pCur){
int i;
for(i=0; i<pCur->nRow; i++){
sqlite3_free(pCur->a[i].zWord);
}
pCur->nRow = 0;
pCur->iRow = 0;
pCur->nSearch = 0;
if( pCur->pFullScan ){
sqlite3_finalize(pCur->pFullScan);
pCur->pFullScan = 0;
}
}
/*
** Resize the cursor to hold up to N rows of content
*/
static void spellfix1ResizeCursor(spellfix1_cursor *pCur, int N){
struct spellfix1_row *aNew;
assert( N>=pCur->nRow );
aNew = sqlite3_realloc64(pCur->a, sizeof(pCur->a[0])*N);
if( aNew==0 && N>0 ){
spellfix1ResetCursor(pCur);
sqlite3_free(pCur->a);
pCur->nAlloc = 0;
pCur->a = 0;
}else{
pCur->nAlloc = N;
pCur->a = aNew;
}
}
/*
** Close a fuzzy-search cursor.
*/
static int spellfix1Close(sqlite3_vtab_cursor *cur){
spellfix1_cursor *pCur = (spellfix1_cursor *)cur;
spellfix1ResetCursor(pCur);
spellfix1ResizeCursor(pCur, 0);
sqlite3_free(pCur->zPattern);
sqlite3_free(pCur);
return SQLITE_OK;
}
#define SPELLFIX_IDXNUM_MATCH 0x01 /* word MATCH $str */
#define SPELLFIX_IDXNUM_LANGID 0x02 /* langid == $langid */
#define SPELLFIX_IDXNUM_TOP 0x04 /* top = $top */
#define SPELLFIX_IDXNUM_SCOPE 0x08 /* scope = $scope */
#define SPELLFIX_IDXNUM_DISTLT 0x10 /* distance < $distance */
#define SPELLFIX_IDXNUM_DISTLE 0x20 /* distance <= $distance */
#define SPELLFIX_IDXNUM_ROWID 0x40 /* rowid = $rowid */
#define SPELLFIX_IDXNUM_DIST (0x10|0x20) /* DISTLT and DISTLE */
/*
**
** The plan number is a bitmask of the SPELLFIX_IDXNUM_* values defined
** above.
**
** filter.argv[*] values contains $str, $langid, $top, $scope and $rowid
** if specified and in that order.
*/
static int spellfix1BestIndex(sqlite3_vtab *tab, sqlite3_index_info *pIdxInfo){
int iPlan = 0;
int iLangTerm = -1;
int iTopTerm = -1;
int iScopeTerm = -1;
int iDistTerm = -1;
int iRowidTerm = -1;
int i;
const struct sqlite3_index_constraint *pConstraint;
pConstraint = pIdxInfo->aConstraint;
for(i=0; i<pIdxInfo->nConstraint; i++, pConstraint++){
if( pConstraint->usable==0 ) continue;
/* Terms of the form: word MATCH $str */
if( (iPlan & SPELLFIX_IDXNUM_MATCH)==0
&& pConstraint->iColumn==SPELLFIX_COL_WORD
&& pConstraint->op==SQLITE_INDEX_CONSTRAINT_MATCH
){
iPlan |= SPELLFIX_IDXNUM_MATCH;
pIdxInfo->aConstraintUsage[i].argvIndex = 1;
pIdxInfo->aConstraintUsage[i].omit = 1;
}
/* Terms of the form: langid = $langid */
if( (iPlan & SPELLFIX_IDXNUM_LANGID)==0
&& pConstraint->iColumn==SPELLFIX_COL_LANGID
&& pConstraint->op==SQLITE_INDEX_CONSTRAINT_EQ
){
iPlan |= SPELLFIX_IDXNUM_LANGID;
iLangTerm = i;
}
/* Terms of the form: top = $top */
if( (iPlan & SPELLFIX_IDXNUM_TOP)==0
&& pConstraint->iColumn==SPELLFIX_COL_TOP
&& pConstraint->op==SQLITE_INDEX_CONSTRAINT_EQ
){
iPlan |= SPELLFIX_IDXNUM_TOP;
iTopTerm = i;
}
/* Terms of the form: scope = $scope */
if( (iPlan & SPELLFIX_IDXNUM_SCOPE)==0
&& pConstraint->iColumn==SPELLFIX_COL_SCOPE
&& pConstraint->op==SQLITE_INDEX_CONSTRAINT_EQ
){
iPlan |= SPELLFIX_IDXNUM_SCOPE;
iScopeTerm = i;
}
/* Terms of the form: distance < $dist or distance <= $dist */
if( (iPlan & SPELLFIX_IDXNUM_DIST)==0
&& pConstraint->iColumn==SPELLFIX_COL_DISTANCE
&& (pConstraint->op==SQLITE_INDEX_CONSTRAINT_LT
|| pConstraint->op==SQLITE_INDEX_CONSTRAINT_LE)
){
if( pConstraint->op==SQLITE_INDEX_CONSTRAINT_LT ){
iPlan |= SPELLFIX_IDXNUM_DISTLT;
}else{
iPlan |= SPELLFIX_IDXNUM_DISTLE;
}
iDistTerm = i;
}
/* Terms of the form: distance < $dist or distance <= $dist */
if( (iPlan & SPELLFIX_IDXNUM_ROWID)==0
&& pConstraint->iColumn<0
&& pConstraint->op==SQLITE_INDEX_CONSTRAINT_EQ
){
iPlan |= SPELLFIX_IDXNUM_ROWID;
iRowidTerm = i;
}
}
if( iPlan&SPELLFIX_IDXNUM_MATCH ){
int idx = 2;
pIdxInfo->idxNum = iPlan;
if( pIdxInfo->nOrderBy==1
&& pIdxInfo->aOrderBy[0].iColumn==SPELLFIX_COL_SCORE
&& pIdxInfo->aOrderBy[0].desc==0
){
pIdxInfo->orderByConsumed = 1; /* Default order by iScore */
}
if( iPlan&SPELLFIX_IDXNUM_LANGID ){
pIdxInfo->aConstraintUsage[iLangTerm].argvIndex = idx++;
pIdxInfo->aConstraintUsage[iLangTerm].omit = 1;
}
if( iPlan&SPELLFIX_IDXNUM_TOP ){
pIdxInfo->aConstraintUsage[iTopTerm].argvIndex = idx++;
pIdxInfo->aConstraintUsage[iTopTerm].omit = 1;
}
if( iPlan&SPELLFIX_IDXNUM_SCOPE ){
pIdxInfo->aConstraintUsage[iScopeTerm].argvIndex = idx++;
pIdxInfo->aConstraintUsage[iScopeTerm].omit = 1;
}
if( iPlan&SPELLFIX_IDXNUM_DIST ){
pIdxInfo->aConstraintUsage[iDistTerm].argvIndex = idx++;
pIdxInfo->aConstraintUsage[iDistTerm].omit = 1;
}
pIdxInfo->estimatedCost = 1e5;
}else if( (iPlan & SPELLFIX_IDXNUM_ROWID) ){
pIdxInfo->idxNum = SPELLFIX_IDXNUM_ROWID;
pIdxInfo->aConstraintUsage[iRowidTerm].argvIndex = 1;
pIdxInfo->aConstraintUsage[iRowidTerm].omit = 1;
pIdxInfo->estimatedCost = 5;
}else{
pIdxInfo->idxNum = 0;
pIdxInfo->estimatedCost = 1e50;
}
return SQLITE_OK;
}
/*
** Open a new fuzzy-search cursor.
*/
static int spellfix1Open(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor){
spellfix1_vtab *p = (spellfix1_vtab*)pVTab;
spellfix1_cursor *pCur;
pCur = sqlite3_malloc64( sizeof(*pCur) );
if( pCur==0 ) return SQLITE_NOMEM;
memset(pCur, 0, sizeof(*pCur));
pCur->pVTab = p;
*ppCursor = &pCur->base;
return SQLITE_OK;
}
/*
** Adjust a distance measurement by the words rank in order to show
** preference to common words.
*/
static int spellfix1Score(int iDistance, int iRank){
int iLog2;
for(iLog2=0; iRank>0; iLog2++, iRank>>=1){}
return iDistance + 32 - iLog2;
}
/*
** Compare two spellfix1_row objects for sorting purposes in qsort() such
** that they sort in order of increasing distance.
*/
static int SQLITE_CDECL spellfix1RowCompare(const void *A, const void *B){
const struct spellfix1_row *a = (const struct spellfix1_row*)A;
const struct spellfix1_row *b = (const struct spellfix1_row*)B;
return a->iScore - b->iScore;
}
/*
** A structure used to pass information from spellfix1FilterForMatch()
** into spellfix1RunQuery().
*/
typedef struct MatchQuery {
spellfix1_cursor *pCur; /* The cursor being queried */
sqlite3_stmt *pStmt; /* shadow table query statment */
char zHash[SPELLFIX_MX_HASH]; /* The current phonehash for zPattern */
const char *zPattern; /* Transliterated input string */
int nPattern; /* Length of zPattern */
EditDist3FromString *pMatchStr3; /* Original unicode string */
EditDist3Config *pConfig3; /* Edit-distance cost coefficients */
const EditDist3Lang *pLang; /* The selected language coefficients */
int iLang; /* The language id */
int iScope; /* Default scope */
int iMaxDist; /* Maximum allowed edit distance, or -1 */
int rc; /* Error code */
int nRun; /* Number of prior runs for the same zPattern */
char azPrior[SPELLFIX_MX_RUN][SPELLFIX_MX_HASH]; /* Prior hashes */
} MatchQuery;
/*
** Run a query looking for the best matches against zPattern using
** zHash as the character class seed hash.
*/
static void spellfix1RunQuery(MatchQuery *p, const char *zQuery, int nQuery){
const char *zK1;
const char *zWord;
int iDist;
int iRank;
int iScore;
int iWorst = 0;
int idx;
int idxWorst = -1;
int i;
int iScope = p->iScope;
spellfix1_cursor *pCur = p->pCur;
sqlite3_stmt *pStmt = p->pStmt;
char zHash1[SPELLFIX_MX_HASH];
char zHash2[SPELLFIX_MX_HASH];
char *zClass;
int nClass;
int rc;
if( pCur->a==0 || p->rc ) return; /* Prior memory allocation failure */
zClass = (char*)phoneticHash((unsigned char*)zQuery, nQuery);
if( zClass==0 ){
p->rc = SQLITE_NOMEM;
return;
}
nClass = (int)strlen(zClass);
if( nClass>SPELLFIX_MX_HASH-2 ){
nClass = SPELLFIX_MX_HASH-2;
zClass[nClass] = 0;
}
if( nClass<=iScope ){
if( nClass>2 ){
iScope = nClass-1;
}else{
iScope = nClass;
}
}
memcpy(zHash1, zClass, iScope);
sqlite3_free(zClass);
zHash1[iScope] = 0;
memcpy(zHash2, zHash1, iScope);
zHash2[iScope] = 'Z';
zHash2[iScope+1] = 0;
#if SPELLFIX_MX_RUN>1
for(i=0; i<p->nRun; i++){
if( strcmp(p->azPrior[i], zHash1)==0 ) return;
}
#endif
assert( p->nRun<SPELLFIX_MX_RUN );
memcpy(p->azPrior[p->nRun++], zHash1, iScope+1);
if( sqlite3_bind_text(pStmt, 1, zHash1, -1, SQLITE_STATIC)==SQLITE_NOMEM
|| sqlite3_bind_text(pStmt, 2, zHash2, -1, SQLITE_STATIC)==SQLITE_NOMEM
){
p->rc = SQLITE_NOMEM;
return;
}
#if SPELLFIX_MX_RUN>1
for(i=0; i<pCur->nRow; i++){
if( pCur->a[i].iScore>iWorst ){
iWorst = pCur->a[i].iScore;
idxWorst = i;
}
}
#endif
while( sqlite3_step(pStmt)==SQLITE_ROW ){
int iMatchlen = -1;
iRank = sqlite3_column_int(pStmt, 2);
if( p->pMatchStr3 ){
int nWord = sqlite3_column_bytes(pStmt, 1);
zWord = (const char*)sqlite3_column_text(pStmt, 1);
iDist = editDist3Core(p->pMatchStr3, zWord, nWord, p->pLang, &iMatchlen);
}else{
zK1 = (const char*)sqlite3_column_text(pStmt, 3);
if( zK1==0 ) continue;
iDist = editdist1(p->zPattern, zK1, 0);
}
if( iDist<0 ){
p->rc = SQLITE_NOMEM;
break;
}
pCur->nSearch++;
/* If there is a "distance < $dist" or "distance <= $dist" constraint,
** check if this row meets it. If not, jump back up to the top of the
** loop to process the next row. Otherwise, if the row does match the
** distance constraint, check if the pCur->a[] array is already full.
** If it is and no explicit "top = ?" constraint was present in the
** query, grow the array to ensure there is room for the new entry. */
assert( (p->iMaxDist>=0)==((pCur->idxNum & SPELLFIX_IDXNUM_DIST) ? 1 : 0) );
if( p->iMaxDist>=0 ){
if( iDist>p->iMaxDist ) continue;
if( pCur->nRow>=pCur->nAlloc && (pCur->idxNum & SPELLFIX_IDXNUM_TOP)==0 ){
spellfix1ResizeCursor(pCur, pCur->nAlloc*2 + 10);
if( pCur->a==0 ) break;
}
}
iScore = spellfix1Score(iDist,iRank);
if( pCur->nRow<pCur->nAlloc ){
idx = pCur->nRow;
}else if( iScore<iWorst ){
idx = idxWorst;
sqlite3_free(pCur->a[idx].zWord);
}else{
continue;
}
pCur->a[idx].zWord = sqlite3_mprintf("%s", sqlite3_column_text(pStmt, 1));
if( pCur->a[idx].zWord==0 ){
p->rc = SQLITE_NOMEM;
break;
}
pCur->a[idx].iRowid = sqlite3_column_int64(pStmt, 0);
pCur->a[idx].iRank = iRank;
pCur->a[idx].iDistance = iDist;
pCur->a[idx].iScore = iScore;
pCur->a[idx].iMatchlen = iMatchlen;
memcpy(pCur->a[idx].zHash, zHash1, iScope+1);
if( pCur->nRow<pCur->nAlloc ) pCur->nRow++;
if( pCur->nRow==pCur->nAlloc ){
iWorst = pCur->a[0].iScore;
idxWorst = 0;
for(i=1; i<pCur->nRow; i++){
iScore = pCur->a[i].iScore;
if( iWorst<iScore ){
iWorst = iScore;
idxWorst = i;
}
}
}
}
rc = sqlite3_reset(pStmt);
if( rc ) p->rc = rc;
}
/*
** This version of the xFilter method work if the MATCH term is present
** and we are doing a scan.
*/
static int spellfix1FilterForMatch(
spellfix1_cursor *pCur,
int argc,
sqlite3_value **argv
){
int idxNum = pCur->idxNum;
const unsigned char *zMatchThis; /* RHS of the MATCH operator */
EditDist3FromString *pMatchStr3 = 0; /* zMatchThis as an editdist string */
char *zPattern; /* Transliteration of zMatchThis */
int nPattern; /* Length of zPattern */
int iLimit = 20; /* Max number of rows of output */
int iScope = 3; /* Use this many characters of zClass */
int iLang = 0; /* Language code */
char *zSql; /* SQL of shadow table query */
sqlite3_stmt *pStmt = 0; /* Shadow table query */
int rc; /* Result code */
int idx = 1; /* Next available filter parameter */
spellfix1_vtab *p = pCur->pVTab; /* The virtual table that owns pCur */
MatchQuery x; /* For passing info to RunQuery() */
/* Load the cost table if we have not already done so */
if( p->zCostTable!=0 && p->pConfig3==0 ){
p->pConfig3 = sqlite3_malloc64( sizeof(p->pConfig3[0]) );
if( p->pConfig3==0 ) return SQLITE_NOMEM;
memset(p->pConfig3, 0, sizeof(p->pConfig3[0]));
rc = editDist3ConfigLoad(p->pConfig3, p->db, p->zCostTable);
if( rc ) return rc;
}
memset(&x, 0, sizeof(x));
x.iScope = 3; /* Default scope if none specified by "WHERE scope=N" */
x.iMaxDist = -1; /* Maximum allowed edit distance */
if( idxNum&2 ){
iLang = sqlite3_value_int(argv[idx++]);
}
if( idxNum&4 ){
iLimit = sqlite3_value_int(argv[idx++]);
if( iLimit<1 ) iLimit = 1;
}
if( idxNum&8 ){
x.iScope = sqlite3_value_int(argv[idx++]);
if( x.iScope<1 ) x.iScope = 1;
if( x.iScope>SPELLFIX_MX_HASH-2 ) x.iScope = SPELLFIX_MX_HASH-2;
}
if( idxNum&(16|32) ){
x.iMaxDist = sqlite3_value_int(argv[idx++]);
if( idxNum&16 ) x.iMaxDist--;
if( x.iMaxDist<0 ) x.iMaxDist = 0;
}
spellfix1ResetCursor(pCur);
spellfix1ResizeCursor(pCur, iLimit);
zMatchThis = sqlite3_value_text(argv[0]);
if( zMatchThis==0 ) return SQLITE_OK;
if( p->pConfig3 ){
x.pLang = editDist3FindLang(p->pConfig3, iLang);
pMatchStr3 = editDist3FromStringNew(x.pLang, (const char*)zMatchThis, -1);
if( pMatchStr3==0 ){
x.rc = SQLITE_NOMEM;
goto filter_exit;
}
}else{
x.pLang = 0;
}
zPattern = (char*)transliterate(zMatchThis, sqlite3_value_bytes(argv[0]));
sqlite3_free(pCur->zPattern);
pCur->zPattern = zPattern;
if( zPattern==0 ){
x.rc = SQLITE_NOMEM;
goto filter_exit;
}
nPattern = (int)strlen(zPattern);
if( zPattern[nPattern-1]=='*' ) nPattern--;
zSql = sqlite3_mprintf(
"SELECT id, word, rank, k1"
" FROM \"%w\".\"%w_vocab\""
" WHERE langid=%d AND k2>=?1 AND k2<?2",
p->zDbName, p->zTableName, iLang
);
if( zSql==0 ){
x.rc = SQLITE_NOMEM;
pStmt = 0;
goto filter_exit;
}
rc = sqlite3_prepare_v2(p->db, zSql, -1, &pStmt, 0);
sqlite3_free(zSql);
pCur->iLang = iLang;
x.pCur = pCur;
x.pStmt = pStmt;
x.zPattern = zPattern;
x.nPattern = nPattern;
x.pMatchStr3 = pMatchStr3;
x.iLang = iLang;
x.rc = rc;
x.pConfig3 = p->pConfig3;
if( x.rc==SQLITE_OK ){
spellfix1RunQuery(&x, zPattern, nPattern);
}
if( pCur->a ){
qsort(pCur->a, pCur->nRow, sizeof(pCur->a[0]), spellfix1RowCompare);
pCur->iTop = iLimit;
pCur->iScope = iScope;
}else{
x.rc = SQLITE_NOMEM;
}
filter_exit:
sqlite3_finalize(pStmt);
editDist3FromStringDelete(pMatchStr3);
return x.rc;
}
/*
** This version of xFilter handles a full-table scan case
*/
static int spellfix1FilterForFullScan(
spellfix1_cursor *pCur,
int argc,
sqlite3_value **argv
){
int rc = SQLITE_OK;
int idxNum = pCur->idxNum;
char *zSql;
spellfix1_vtab *pVTab = pCur->pVTab;
spellfix1ResetCursor(pCur);
assert( idxNum==0 || idxNum==64 );
zSql = sqlite3_mprintf(
"SELECT word, rank, NULL, langid, id FROM \"%w\".\"%w_vocab\"%s",
pVTab->zDbName, pVTab->zTableName,
((idxNum & 64) ? " WHERE rowid=?" : "")
);
if( zSql==0 ) return SQLITE_NOMEM;
rc = sqlite3_prepare_v2(pVTab->db, zSql, -1, &pCur->pFullScan, 0);
sqlite3_free(zSql);
if( rc==SQLITE_OK && (idxNum & 64) ){
assert( argc==1 );
rc = sqlite3_bind_value(pCur->pFullScan, 1, argv[0]);
}
pCur->nRow = pCur->iRow = 0;
if( rc==SQLITE_OK ){
rc = sqlite3_step(pCur->pFullScan);
if( rc==SQLITE_ROW ){ pCur->iRow = -1; rc = SQLITE_OK; }
if( rc==SQLITE_DONE ){ rc = SQLITE_OK; }
}else{
pCur->iRow = 0;
}
return rc;
}
/*
** Called to "rewind" a cursor back to the beginning so that
** it starts its output over again. Always called at least once
** prior to any spellfix1Column, spellfix1Rowid, or spellfix1Eof call.
*/
static int spellfix1Filter(
sqlite3_vtab_cursor *cur,
int idxNum, const char *idxStr,
int argc, sqlite3_value **argv
){
spellfix1_cursor *pCur = (spellfix1_cursor *)cur;
int rc;
pCur->idxNum = idxNum;
if( idxNum & 1 ){
rc = spellfix1FilterForMatch(pCur, argc, argv);
}else{
rc = spellfix1FilterForFullScan(pCur, argc, argv);
}
return rc;
}
/*
** Advance a cursor to its next row of output
*/
static int spellfix1Next(sqlite3_vtab_cursor *cur){
spellfix1_cursor *pCur = (spellfix1_cursor *)cur;
int rc = SQLITE_OK;
if( pCur->iRow < pCur->nRow ){
if( pCur->pFullScan ){
rc = sqlite3_step(pCur->pFullScan);
if( rc!=SQLITE_ROW ) pCur->iRow = pCur->nRow;
if( rc==SQLITE_ROW || rc==SQLITE_DONE ) rc = SQLITE_OK;
}else{
pCur->iRow++;
}
}
return rc;
}
/*
** Return TRUE if we are at the end-of-file
*/
static int spellfix1Eof(sqlite3_vtab_cursor *cur){
spellfix1_cursor *pCur = (spellfix1_cursor *)cur;
return pCur->iRow>=pCur->nRow;
}
/*
** Return columns from the current row.
*/
static int spellfix1Column(
sqlite3_vtab_cursor *cur,
sqlite3_context *ctx,
int i
){
spellfix1_cursor *pCur = (spellfix1_cursor*)cur;
if( pCur->pFullScan ){
if( i<=SPELLFIX_COL_LANGID ){
sqlite3_result_value(ctx, sqlite3_column_value(pCur->pFullScan, i));
}else{
sqlite3_result_null(ctx);
}
return SQLITE_OK;
}
switch( i ){
case SPELLFIX_COL_WORD: {
sqlite3_result_text(ctx, pCur->a[pCur->iRow].zWord, -1, SQLITE_STATIC);
break;
}
case SPELLFIX_COL_RANK: {
sqlite3_result_int(ctx, pCur->a[pCur->iRow].iRank);
break;
}
case SPELLFIX_COL_DISTANCE: {
sqlite3_result_int(ctx, pCur->a[pCur->iRow].iDistance);
break;
}
case SPELLFIX_COL_LANGID: {
sqlite3_result_int(ctx, pCur->iLang);
break;
}
case SPELLFIX_COL_SCORE: {
sqlite3_result_int(ctx, pCur->a[pCur->iRow].iScore);
break;
}
case SPELLFIX_COL_MATCHLEN: {
int iMatchlen = pCur->a[pCur->iRow].iMatchlen;
if( iMatchlen<0 ){
int nPattern = (int)strlen(pCur->zPattern);
char *zWord = pCur->a[pCur->iRow].zWord;
int nWord = (int)strlen(zWord);
if( nPattern>0 && pCur->zPattern[nPattern-1]=='*' ){
char *zTranslit;
int res;
zTranslit = (char *)transliterate((unsigned char *)zWord, nWord);
if( !zTranslit ) return SQLITE_NOMEM;
res = editdist1(pCur->zPattern, zTranslit, &iMatchlen);
sqlite3_free(zTranslit);
if( res<0 ) return SQLITE_NOMEM;
iMatchlen = translen_to_charlen(zWord, nWord, iMatchlen);
}else{
iMatchlen = utf8Charlen(zWord, nWord);
}
}
sqlite3_result_int(ctx, iMatchlen);
break;
}
case SPELLFIX_COL_PHONEHASH: {
sqlite3_result_text(ctx, pCur->a[pCur->iRow].zHash, -1, SQLITE_STATIC);
break;
}
case SPELLFIX_COL_TOP: {
sqlite3_result_int(ctx, pCur->iTop);
break;
}
case SPELLFIX_COL_SCOPE: {
sqlite3_result_int(ctx, pCur->iScope);
break;
}
case SPELLFIX_COL_SRCHCNT: {
sqlite3_result_int(ctx, pCur->nSearch);
break;
}
default: {
sqlite3_result_null(ctx);
break;
}
}
return SQLITE_OK;
}
/*
** The rowid.
*/
static int spellfix1Rowid(sqlite3_vtab_cursor *cur, sqlite_int64 *pRowid){
spellfix1_cursor *pCur = (spellfix1_cursor*)cur;
if( pCur->pFullScan ){
*pRowid = sqlite3_column_int64(pCur->pFullScan, 4);
}else{
*pRowid = pCur->a[pCur->iRow].iRowid;
}
return SQLITE_OK;
}
/*
** This function is called by the xUpdate() method. It returns a string
** containing the conflict mode that xUpdate() should use for the current
** operation. One of: "ROLLBACK", "IGNORE", "ABORT" or "REPLACE".
*/
static const char *spellfix1GetConflict(sqlite3 *db){
static const char *azConflict[] = {
/* Note: Instead of "FAIL" - "ABORT". */
"ROLLBACK", "IGNORE", "ABORT", "ABORT", "REPLACE"
};
int eConflict = sqlite3_vtab_on_conflict(db);
assert( eConflict==SQLITE_ROLLBACK || eConflict==SQLITE_IGNORE
|| eConflict==SQLITE_FAIL || eConflict==SQLITE_ABORT
|| eConflict==SQLITE_REPLACE
);
assert( SQLITE_ROLLBACK==1 );
assert( SQLITE_IGNORE==2 );
assert( SQLITE_FAIL==3 );
assert( SQLITE_ABORT==4 );
assert( SQLITE_REPLACE==5 );
return azConflict[eConflict-1];
}
/*
** The xUpdate() method.
*/
static int spellfix1Update(
sqlite3_vtab *pVTab,
int argc,
sqlite3_value **argv,
sqlite_int64 *pRowid
){
int rc = SQLITE_OK;
sqlite3_int64 rowid, newRowid;
spellfix1_vtab *p = (spellfix1_vtab*)pVTab;
sqlite3 *db = p->db;
if( argc==1 ){
/* A delete operation on the rowid given by argv[0] */
rowid = *pRowid = sqlite3_value_int64(argv[0]);
spellfix1DbExec(&rc, db, "DELETE FROM \"%w\".\"%w_vocab\" "
" WHERE id=%lld",
p->zDbName, p->zTableName, rowid);
}else{
const unsigned char *zWord = sqlite3_value_text(argv[SPELLFIX_COL_WORD+2]);
int nWord = sqlite3_value_bytes(argv[SPELLFIX_COL_WORD+2]);
int iLang = sqlite3_value_int(argv[SPELLFIX_COL_LANGID+2]);
int iRank = sqlite3_value_int(argv[SPELLFIX_COL_RANK+2]);
const unsigned char *zSoundslike =
sqlite3_value_text(argv[SPELLFIX_COL_SOUNDSLIKE+2]);
int nSoundslike = sqlite3_value_bytes(argv[SPELLFIX_COL_SOUNDSLIKE+2]);
char *zK1, *zK2;
int i;
char c;
const char *zConflict = spellfix1GetConflict(db);
if( zWord==0 ){
/* Inserts of the form: INSERT INTO table(command) VALUES('xyzzy');
** cause zWord to be NULL, so we look at the "command" column to see
** what special actions to take */
const char *zCmd =
(const char*)sqlite3_value_text(argv[SPELLFIX_COL_COMMAND+2]);
if( zCmd==0 ){
pVTab->zErrMsg = sqlite3_mprintf("NOT NULL constraint failed: %s.word",
p->zTableName);
return SQLITE_CONSTRAINT_NOTNULL;
}
if( strcmp(zCmd,"reset")==0 ){
/* Reset the edit cost table (if there is one). */
editDist3ConfigDelete(p->pConfig3);
p->pConfig3 = 0;
return SQLITE_OK;
}
if( strncmp(zCmd,"edit_cost_table=",16)==0 ){
editDist3ConfigDelete(p->pConfig3);
p->pConfig3 = 0;
sqlite3_free(p->zCostTable);
p->zCostTable = spellfix1Dequote(zCmd+16);
if( p->zCostTable==0 ) return SQLITE_NOMEM;
if( p->zCostTable[0]==0 || sqlite3_stricmp(p->zCostTable,"null")==0 ){
sqlite3_free(p->zCostTable);
p->zCostTable = 0;
}
return SQLITE_OK;
}
pVTab->zErrMsg = sqlite3_mprintf("unknown value for %s.command: \"%w\"",
p->zTableName, zCmd);
return SQLITE_ERROR;
}
if( iRank<1 ) iRank = 1;
if( zSoundslike ){
zK1 = (char*)transliterate(zSoundslike, nSoundslike);
}else{
zK1 = (char*)transliterate(zWord, nWord);
}
if( zK1==0 ) return SQLITE_NOMEM;
for(i=0; (c = zK1[i])!=0; i++){
if( c>='A' && c<='Z' ) zK1[i] += 'a' - 'A';
}
zK2 = (char*)phoneticHash((const unsigned char*)zK1, i);
if( zK2==0 ){
sqlite3_free(zK1);
return SQLITE_NOMEM;
}
if( sqlite3_value_type(argv[0])==SQLITE_NULL ){
if( sqlite3_value_type(argv[1])==SQLITE_NULL ){
spellfix1DbExec(&rc, db,
"INSERT INTO \"%w\".\"%w_vocab\"(rank,langid,word,k1,k2) "
"VALUES(%d,%d,%Q,%Q,%Q)",
p->zDbName, p->zTableName,
iRank, iLang, zWord, zK1, zK2
);
}else{
newRowid = sqlite3_value_int64(argv[1]);
spellfix1DbExec(&rc, db,
"INSERT OR %s INTO \"%w\".\"%w_vocab\"(id,rank,langid,word,k1,k2) "
"VALUES(%lld,%d,%d,%Q,%Q,%Q)",
zConflict, p->zDbName, p->zTableName,
newRowid, iRank, iLang, zWord, zK1, zK2
);
}
*pRowid = sqlite3_last_insert_rowid(db);
}else{
rowid = sqlite3_value_int64(argv[0]);
newRowid = *pRowid = sqlite3_value_int64(argv[1]);
spellfix1DbExec(&rc, db,
"UPDATE OR %s \"%w\".\"%w_vocab\" SET id=%lld, rank=%d, langid=%d,"
" word=%Q, k1=%Q, k2=%Q WHERE id=%lld",
zConflict, p->zDbName, p->zTableName, newRowid, iRank, iLang,
zWord, zK1, zK2, rowid
);
}
sqlite3_free(zK1);
sqlite3_free(zK2);
}
return rc;
}
/*
** Rename the spellfix1 table.
*/
static int spellfix1Rename(sqlite3_vtab *pVTab, const char *zNew){
spellfix1_vtab *p = (spellfix1_vtab*)pVTab;
sqlite3 *db = p->db;
int rc = SQLITE_OK;
char *zNewName = sqlite3_mprintf("%s", zNew);
if( zNewName==0 ){
return SQLITE_NOMEM;
}
spellfix1DbExec(&rc, db,
"ALTER TABLE \"%w\".\"%w_vocab\" RENAME TO \"%w_vocab\"",
p->zDbName, p->zTableName, zNewName
);
if( rc==SQLITE_OK ){
sqlite3_free(p->zTableName);
p->zTableName = zNewName;
}else{
sqlite3_free(zNewName);
}
return rc;
}
/*
** A virtual table module that provides fuzzy search.
*/
static sqlite3_module spellfix1Module = {
0, /* iVersion */
spellfix1Create, /* xCreate - handle CREATE VIRTUAL TABLE */
spellfix1Connect, /* xConnect - reconnected to an existing table */
spellfix1BestIndex, /* xBestIndex - figure out how to do a query */
spellfix1Disconnect, /* xDisconnect - close a connection */
spellfix1Destroy, /* xDestroy - handle DROP TABLE */
spellfix1Open, /* xOpen - open a cursor */
spellfix1Close, /* xClose - close a cursor */
spellfix1Filter, /* xFilter - configure scan constraints */
spellfix1Next, /* xNext - advance a cursor */
spellfix1Eof, /* xEof - check for end of scan */
spellfix1Column, /* xColumn - read data */
spellfix1Rowid, /* xRowid - read data */
spellfix1Update, /* xUpdate */
0, /* xBegin */
0, /* xSync */
0, /* xCommit */
0, /* xRollback */
0, /* xFindMethod */
spellfix1Rename, /* xRename */
};
/*
** Register the various functions and the virtual table.
*/
static int spellfix1Register(sqlite3 *db){
int rc = SQLITE_OK;
int i;
rc = sqlite3_create_function(db, "spellfix1_translit", 1,
SQLITE_UTF8|SQLITE_DETERMINISTIC, 0,
transliterateSqlFunc, 0, 0);
if( rc==SQLITE_OK ){
rc = sqlite3_create_function(db, "spellfix1_editdist", 2,
SQLITE_UTF8|SQLITE_DETERMINISTIC, 0,
editdistSqlFunc, 0, 0);
}
if( rc==SQLITE_OK ){
rc = sqlite3_create_function(db, "spellfix1_phonehash", 1,
SQLITE_UTF8|SQLITE_DETERMINISTIC, 0,
phoneticHashSqlFunc, 0, 0);
}
if( rc==SQLITE_OK ){
rc = sqlite3_create_function(db, "spellfix1_scriptcode", 1,
SQLITE_UTF8|SQLITE_DETERMINISTIC, 0,
scriptCodeSqlFunc, 0, 0);
}
if( rc==SQLITE_OK ){
rc = sqlite3_create_module(db, "spellfix1", &spellfix1Module, 0);
}
if( rc==SQLITE_OK ){
rc = editDist3Install(db);
}
/* Verify sanity of the translit[] table */
for(i=0; i<sizeof(translit)/sizeof(translit[0])-1; i++){
assert( translit[i].cFrom<translit[i+1].cFrom );
}
return rc;
}
#endif /* SQLITE_OMIT_VIRTUALTABLE */
/*
** Extension load function.
*/
#ifdef _WIN32
__declspec(dllexport)
#endif
int sqlite3_spellfix_init(
sqlite3 *db,
char **pzErrMsg,
const sqlite3_api_routines *pApi
){
SQLITE_EXTENSION_INIT2(pApi);
#ifndef SQLITE_OMIT_VIRTUALTABLE
return spellfix1Register(db);
#endif
return SQLITE_OK;
}