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mirror of https://github.com/tursodatabase/libsql.git synced 2024-12-16 16:08:48 +00:00
libsql/libsql-sqlite3/ext/fts5/fts5_tokenize.c
2023-10-16 13:58:16 +02:00

1416 lines
37 KiB
C

/*
** 2014 May 31
**
** 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.
**
******************************************************************************
*/
#include "fts5Int.h"
/**************************************************************************
** Start of ascii tokenizer implementation.
*/
/*
** For tokenizers with no "unicode" modifier, the set of token characters
** is the same as the set of ASCII range alphanumeric characters.
*/
static unsigned char aAsciiTokenChar[128] = {
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* 0x00..0x0F */
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* 0x10..0x1F */
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* 0x20..0x2F */
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, /* 0x30..0x3F */
0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, /* 0x40..0x4F */
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, /* 0x50..0x5F */
0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, /* 0x60..0x6F */
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, /* 0x70..0x7F */
};
typedef struct AsciiTokenizer AsciiTokenizer;
struct AsciiTokenizer {
unsigned char aTokenChar[128];
};
static void fts5AsciiAddExceptions(
AsciiTokenizer *p,
const char *zArg,
int bTokenChars
){
int i;
for(i=0; zArg[i]; i++){
if( (zArg[i] & 0x80)==0 ){
p->aTokenChar[(int)zArg[i]] = (unsigned char)bTokenChars;
}
}
}
/*
** Delete a "ascii" tokenizer.
*/
static void fts5AsciiDelete(Fts5Tokenizer *p){
sqlite3_free(p);
}
/*
** Create an "ascii" tokenizer.
*/
static int fts5AsciiCreate(
void *pUnused,
const char **azArg, int nArg,
Fts5Tokenizer **ppOut
){
int rc = SQLITE_OK;
AsciiTokenizer *p = 0;
UNUSED_PARAM(pUnused);
if( nArg%2 ){
rc = SQLITE_ERROR;
}else{
p = sqlite3_malloc(sizeof(AsciiTokenizer));
if( p==0 ){
rc = SQLITE_NOMEM;
}else{
int i;
memset(p, 0, sizeof(AsciiTokenizer));
memcpy(p->aTokenChar, aAsciiTokenChar, sizeof(aAsciiTokenChar));
for(i=0; rc==SQLITE_OK && i<nArg; i+=2){
const char *zArg = azArg[i+1];
if( 0==sqlite3_stricmp(azArg[i], "tokenchars") ){
fts5AsciiAddExceptions(p, zArg, 1);
}else
if( 0==sqlite3_stricmp(azArg[i], "separators") ){
fts5AsciiAddExceptions(p, zArg, 0);
}else{
rc = SQLITE_ERROR;
}
}
if( rc!=SQLITE_OK ){
fts5AsciiDelete((Fts5Tokenizer*)p);
p = 0;
}
}
}
*ppOut = (Fts5Tokenizer*)p;
return rc;
}
static void asciiFold(char *aOut, const char *aIn, int nByte){
int i;
for(i=0; i<nByte; i++){
char c = aIn[i];
if( c>='A' && c<='Z' ) c += 32;
aOut[i] = c;
}
}
/*
** Tokenize some text using the ascii tokenizer.
*/
static int fts5AsciiTokenize(
Fts5Tokenizer *pTokenizer,
void *pCtx,
int iUnused,
const char *pText, int nText,
int (*xToken)(void*, int, const char*, int nToken, int iStart, int iEnd)
){
AsciiTokenizer *p = (AsciiTokenizer*)pTokenizer;
int rc = SQLITE_OK;
int ie;
int is = 0;
char aFold[64];
int nFold = sizeof(aFold);
char *pFold = aFold;
unsigned char *a = p->aTokenChar;
UNUSED_PARAM(iUnused);
while( is<nText && rc==SQLITE_OK ){
int nByte;
/* Skip any leading divider characters. */
while( is<nText && ((pText[is]&0x80)==0 && a[(int)pText[is]]==0) ){
is++;
}
if( is==nText ) break;
/* Count the token characters */
ie = is+1;
while( ie<nText && ((pText[ie]&0x80) || a[(int)pText[ie]] ) ){
ie++;
}
/* Fold to lower case */
nByte = ie-is;
if( nByte>nFold ){
if( pFold!=aFold ) sqlite3_free(pFold);
pFold = sqlite3_malloc64((sqlite3_int64)nByte*2);
if( pFold==0 ){
rc = SQLITE_NOMEM;
break;
}
nFold = nByte*2;
}
asciiFold(pFold, &pText[is], nByte);
/* Invoke the token callback */
rc = xToken(pCtx, 0, pFold, nByte, is, ie);
is = ie+1;
}
if( pFold!=aFold ) sqlite3_free(pFold);
if( rc==SQLITE_DONE ) rc = SQLITE_OK;
return rc;
}
/**************************************************************************
** Start of unicode61 tokenizer implementation.
*/
/*
** The following two macros - READ_UTF8 and WRITE_UTF8 - have been copied
** from the sqlite3 source file utf.c. If this file is compiled as part
** of the amalgamation, they are not required.
*/
#ifndef SQLITE_AMALGAMATION
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,
};
#define READ_UTF8(zIn, zTerm, c) \
c = *(zIn++); \
if( c>=0xc0 ){ \
c = sqlite3Utf8Trans1[c-0xc0]; \
while( zIn!=zTerm && (*zIn & 0xc0)==0x80 ){ \
c = (c<<6) + (0x3f & *(zIn++)); \
} \
if( c<0x80 \
|| (c&0xFFFFF800)==0xD800 \
|| (c&0xFFFFFFFE)==0xFFFE ){ c = 0xFFFD; } \
}
#define WRITE_UTF8(zOut, c) { \
if( c<0x00080 ){ \
*zOut++ = (unsigned char)(c&0xFF); \
} \
else if( c<0x00800 ){ \
*zOut++ = 0xC0 + (unsigned char)((c>>6)&0x1F); \
*zOut++ = 0x80 + (unsigned char)(c & 0x3F); \
} \
else if( c<0x10000 ){ \
*zOut++ = 0xE0 + (unsigned char)((c>>12)&0x0F); \
*zOut++ = 0x80 + (unsigned char)((c>>6) & 0x3F); \
*zOut++ = 0x80 + (unsigned char)(c & 0x3F); \
}else{ \
*zOut++ = 0xF0 + (unsigned char)((c>>18) & 0x07); \
*zOut++ = 0x80 + (unsigned char)((c>>12) & 0x3F); \
*zOut++ = 0x80 + (unsigned char)((c>>6) & 0x3F); \
*zOut++ = 0x80 + (unsigned char)(c & 0x3F); \
} \
}
#endif /* ifndef SQLITE_AMALGAMATION */
typedef struct Unicode61Tokenizer Unicode61Tokenizer;
struct Unicode61Tokenizer {
unsigned char aTokenChar[128]; /* ASCII range token characters */
char *aFold; /* Buffer to fold text into */
int nFold; /* Size of aFold[] in bytes */
int eRemoveDiacritic; /* True if remove_diacritics=1 is set */
int nException;
int *aiException;
unsigned char aCategory[32]; /* True for token char categories */
};
/* Values for eRemoveDiacritic (must match internals of fts5_unicode2.c) */
#define FTS5_REMOVE_DIACRITICS_NONE 0
#define FTS5_REMOVE_DIACRITICS_SIMPLE 1
#define FTS5_REMOVE_DIACRITICS_COMPLEX 2
static int fts5UnicodeAddExceptions(
Unicode61Tokenizer *p, /* Tokenizer object */
const char *z, /* Characters to treat as exceptions */
int bTokenChars /* 1 for 'tokenchars', 0 for 'separators' */
){
int rc = SQLITE_OK;
int n = (int)strlen(z);
int *aNew;
if( n>0 ){
aNew = (int*)sqlite3_realloc64(p->aiException,
(n+p->nException)*sizeof(int));
if( aNew ){
int nNew = p->nException;
const unsigned char *zCsr = (const unsigned char*)z;
const unsigned char *zTerm = (const unsigned char*)&z[n];
while( zCsr<zTerm ){
u32 iCode;
int bToken;
READ_UTF8(zCsr, zTerm, iCode);
if( iCode<128 ){
p->aTokenChar[iCode] = (unsigned char)bTokenChars;
}else{
bToken = p->aCategory[sqlite3Fts5UnicodeCategory(iCode)];
assert( (bToken==0 || bToken==1) );
assert( (bTokenChars==0 || bTokenChars==1) );
if( bToken!=bTokenChars && sqlite3Fts5UnicodeIsdiacritic(iCode)==0 ){
int i;
for(i=0; i<nNew; i++){
if( (u32)aNew[i]>iCode ) break;
}
memmove(&aNew[i+1], &aNew[i], (nNew-i)*sizeof(int));
aNew[i] = iCode;
nNew++;
}
}
}
p->aiException = aNew;
p->nException = nNew;
}else{
rc = SQLITE_NOMEM;
}
}
return rc;
}
/*
** Return true if the p->aiException[] array contains the value iCode.
*/
static int fts5UnicodeIsException(Unicode61Tokenizer *p, int iCode){
if( p->nException>0 ){
int *a = p->aiException;
int iLo = 0;
int iHi = p->nException-1;
while( iHi>=iLo ){
int iTest = (iHi + iLo) / 2;
if( iCode==a[iTest] ){
return 1;
}else if( iCode>a[iTest] ){
iLo = iTest+1;
}else{
iHi = iTest-1;
}
}
}
return 0;
}
/*
** Delete a "unicode61" tokenizer.
*/
static void fts5UnicodeDelete(Fts5Tokenizer *pTok){
if( pTok ){
Unicode61Tokenizer *p = (Unicode61Tokenizer*)pTok;
sqlite3_free(p->aiException);
sqlite3_free(p->aFold);
sqlite3_free(p);
}
return;
}
static int unicodeSetCategories(Unicode61Tokenizer *p, const char *zCat){
const char *z = zCat;
while( *z ){
while( *z==' ' || *z=='\t' ) z++;
if( *z && sqlite3Fts5UnicodeCatParse(z, p->aCategory) ){
return SQLITE_ERROR;
}
while( *z!=' ' && *z!='\t' && *z!='\0' ) z++;
}
sqlite3Fts5UnicodeAscii(p->aCategory, p->aTokenChar);
return SQLITE_OK;
}
/*
** Create a "unicode61" tokenizer.
*/
static int fts5UnicodeCreate(
void *pUnused,
const char **azArg, int nArg,
Fts5Tokenizer **ppOut
){
int rc = SQLITE_OK; /* Return code */
Unicode61Tokenizer *p = 0; /* New tokenizer object */
UNUSED_PARAM(pUnused);
if( nArg%2 ){
rc = SQLITE_ERROR;
}else{
p = (Unicode61Tokenizer*)sqlite3_malloc(sizeof(Unicode61Tokenizer));
if( p ){
const char *zCat = "L* N* Co";
int i;
memset(p, 0, sizeof(Unicode61Tokenizer));
p->eRemoveDiacritic = FTS5_REMOVE_DIACRITICS_SIMPLE;
p->nFold = 64;
p->aFold = sqlite3_malloc64(p->nFold * sizeof(char));
if( p->aFold==0 ){
rc = SQLITE_NOMEM;
}
/* Search for a "categories" argument */
for(i=0; rc==SQLITE_OK && i<nArg; i+=2){
if( 0==sqlite3_stricmp(azArg[i], "categories") ){
zCat = azArg[i+1];
}
}
if( rc==SQLITE_OK ){
rc = unicodeSetCategories(p, zCat);
}
for(i=0; rc==SQLITE_OK && i<nArg; i+=2){
const char *zArg = azArg[i+1];
if( 0==sqlite3_stricmp(azArg[i], "remove_diacritics") ){
if( (zArg[0]!='0' && zArg[0]!='1' && zArg[0]!='2') || zArg[1] ){
rc = SQLITE_ERROR;
}else{
p->eRemoveDiacritic = (zArg[0] - '0');
assert( p->eRemoveDiacritic==FTS5_REMOVE_DIACRITICS_NONE
|| p->eRemoveDiacritic==FTS5_REMOVE_DIACRITICS_SIMPLE
|| p->eRemoveDiacritic==FTS5_REMOVE_DIACRITICS_COMPLEX
);
}
}else
if( 0==sqlite3_stricmp(azArg[i], "tokenchars") ){
rc = fts5UnicodeAddExceptions(p, zArg, 1);
}else
if( 0==sqlite3_stricmp(azArg[i], "separators") ){
rc = fts5UnicodeAddExceptions(p, zArg, 0);
}else
if( 0==sqlite3_stricmp(azArg[i], "categories") ){
/* no-op */
}else{
rc = SQLITE_ERROR;
}
}
}else{
rc = SQLITE_NOMEM;
}
if( rc!=SQLITE_OK ){
fts5UnicodeDelete((Fts5Tokenizer*)p);
p = 0;
}
*ppOut = (Fts5Tokenizer*)p;
}
return rc;
}
/*
** Return true if, for the purposes of tokenizing with the tokenizer
** passed as the first argument, codepoint iCode is considered a token
** character (not a separator).
*/
static int fts5UnicodeIsAlnum(Unicode61Tokenizer *p, int iCode){
return (
p->aCategory[sqlite3Fts5UnicodeCategory((u32)iCode)]
^ fts5UnicodeIsException(p, iCode)
);
}
static int fts5UnicodeTokenize(
Fts5Tokenizer *pTokenizer,
void *pCtx,
int iUnused,
const char *pText, int nText,
int (*xToken)(void*, int, const char*, int nToken, int iStart, int iEnd)
){
Unicode61Tokenizer *p = (Unicode61Tokenizer*)pTokenizer;
int rc = SQLITE_OK;
unsigned char *a = p->aTokenChar;
unsigned char *zTerm = (unsigned char*)&pText[nText];
unsigned char *zCsr = (unsigned char *)pText;
/* Output buffer */
char *aFold = p->aFold;
int nFold = p->nFold;
const char *pEnd = &aFold[nFold-6];
UNUSED_PARAM(iUnused);
/* Each iteration of this loop gobbles up a contiguous run of separators,
** then the next token. */
while( rc==SQLITE_OK ){
u32 iCode; /* non-ASCII codepoint read from input */
char *zOut = aFold;
int is;
int ie;
/* Skip any separator characters. */
while( 1 ){
if( zCsr>=zTerm ) goto tokenize_done;
if( *zCsr & 0x80 ) {
/* A character outside of the ascii range. Skip past it if it is
** a separator character. Or break out of the loop if it is not. */
is = zCsr - (unsigned char*)pText;
READ_UTF8(zCsr, zTerm, iCode);
if( fts5UnicodeIsAlnum(p, iCode) ){
goto non_ascii_tokenchar;
}
}else{
if( a[*zCsr] ){
is = zCsr - (unsigned char*)pText;
goto ascii_tokenchar;
}
zCsr++;
}
}
/* Run through the tokenchars. Fold them into the output buffer along
** the way. */
while( zCsr<zTerm ){
/* Grow the output buffer so that there is sufficient space to fit the
** largest possible utf-8 character. */
if( zOut>pEnd ){
aFold = sqlite3_malloc64((sqlite3_int64)nFold*2);
if( aFold==0 ){
rc = SQLITE_NOMEM;
goto tokenize_done;
}
zOut = &aFold[zOut - p->aFold];
memcpy(aFold, p->aFold, nFold);
sqlite3_free(p->aFold);
p->aFold = aFold;
p->nFold = nFold = nFold*2;
pEnd = &aFold[nFold-6];
}
if( *zCsr & 0x80 ){
/* An non-ascii-range character. Fold it into the output buffer if
** it is a token character, or break out of the loop if it is not. */
READ_UTF8(zCsr, zTerm, iCode);
if( fts5UnicodeIsAlnum(p,iCode)||sqlite3Fts5UnicodeIsdiacritic(iCode) ){
non_ascii_tokenchar:
iCode = sqlite3Fts5UnicodeFold(iCode, p->eRemoveDiacritic);
if( iCode ) WRITE_UTF8(zOut, iCode);
}else{
break;
}
}else if( a[*zCsr]==0 ){
/* An ascii-range separator character. End of token. */
break;
}else{
ascii_tokenchar:
if( *zCsr>='A' && *zCsr<='Z' ){
*zOut++ = *zCsr + 32;
}else{
*zOut++ = *zCsr;
}
zCsr++;
}
ie = zCsr - (unsigned char*)pText;
}
/* Invoke the token callback */
rc = xToken(pCtx, 0, aFold, zOut-aFold, is, ie);
}
tokenize_done:
if( rc==SQLITE_DONE ) rc = SQLITE_OK;
return rc;
}
/**************************************************************************
** Start of porter stemmer implementation.
*/
/* Any tokens larger than this (in bytes) are passed through without
** stemming. */
#define FTS5_PORTER_MAX_TOKEN 64
typedef struct PorterTokenizer PorterTokenizer;
struct PorterTokenizer {
fts5_tokenizer tokenizer; /* Parent tokenizer module */
Fts5Tokenizer *pTokenizer; /* Parent tokenizer instance */
char aBuf[FTS5_PORTER_MAX_TOKEN + 64];
};
/*
** Delete a "porter" tokenizer.
*/
static void fts5PorterDelete(Fts5Tokenizer *pTok){
if( pTok ){
PorterTokenizer *p = (PorterTokenizer*)pTok;
if( p->pTokenizer ){
p->tokenizer.xDelete(p->pTokenizer);
}
sqlite3_free(p);
}
}
/*
** Create a "porter" tokenizer.
*/
static int fts5PorterCreate(
void *pCtx,
const char **azArg, int nArg,
Fts5Tokenizer **ppOut
){
fts5_api *pApi = (fts5_api*)pCtx;
int rc = SQLITE_OK;
PorterTokenizer *pRet;
void *pUserdata = 0;
const char *zBase = "unicode61";
if( nArg>0 ){
zBase = azArg[0];
}
pRet = (PorterTokenizer*)sqlite3_malloc(sizeof(PorterTokenizer));
if( pRet ){
memset(pRet, 0, sizeof(PorterTokenizer));
rc = pApi->xFindTokenizer(pApi, zBase, &pUserdata, &pRet->tokenizer);
}else{
rc = SQLITE_NOMEM;
}
if( rc==SQLITE_OK ){
int nArg2 = (nArg>0 ? nArg-1 : 0);
const char **azArg2 = (nArg2 ? &azArg[1] : 0);
rc = pRet->tokenizer.xCreate(pUserdata, azArg2, nArg2, &pRet->pTokenizer);
}
if( rc!=SQLITE_OK ){
fts5PorterDelete((Fts5Tokenizer*)pRet);
pRet = 0;
}
*ppOut = (Fts5Tokenizer*)pRet;
return rc;
}
typedef struct PorterContext PorterContext;
struct PorterContext {
void *pCtx;
int (*xToken)(void*, int, const char*, int, int, int);
char *aBuf;
};
typedef struct PorterRule PorterRule;
struct PorterRule {
const char *zSuffix;
int nSuffix;
int (*xCond)(char *zStem, int nStem);
const char *zOutput;
int nOutput;
};
#if 0
static int fts5PorterApply(char *aBuf, int *pnBuf, PorterRule *aRule){
int ret = -1;
int nBuf = *pnBuf;
PorterRule *p;
for(p=aRule; p->zSuffix; p++){
assert( strlen(p->zSuffix)==p->nSuffix );
assert( strlen(p->zOutput)==p->nOutput );
if( nBuf<p->nSuffix ) continue;
if( 0==memcmp(&aBuf[nBuf - p->nSuffix], p->zSuffix, p->nSuffix) ) break;
}
if( p->zSuffix ){
int nStem = nBuf - p->nSuffix;
if( p->xCond==0 || p->xCond(aBuf, nStem) ){
memcpy(&aBuf[nStem], p->zOutput, p->nOutput);
*pnBuf = nStem + p->nOutput;
ret = p - aRule;
}
}
return ret;
}
#endif
static int fts5PorterIsVowel(char c, int bYIsVowel){
return (
c=='a' || c=='e' || c=='i' || c=='o' || c=='u' || (bYIsVowel && c=='y')
);
}
static int fts5PorterGobbleVC(char *zStem, int nStem, int bPrevCons){
int i;
int bCons = bPrevCons;
/* Scan for a vowel */
for(i=0; i<nStem; i++){
if( 0==(bCons = !fts5PorterIsVowel(zStem[i], bCons)) ) break;
}
/* Scan for a consonent */
for(i++; i<nStem; i++){
if( (bCons = !fts5PorterIsVowel(zStem[i], bCons)) ) return i+1;
}
return 0;
}
/* porter rule condition: (m > 0) */
static int fts5Porter_MGt0(char *zStem, int nStem){
return !!fts5PorterGobbleVC(zStem, nStem, 0);
}
/* porter rule condition: (m > 1) */
static int fts5Porter_MGt1(char *zStem, int nStem){
int n;
n = fts5PorterGobbleVC(zStem, nStem, 0);
if( n && fts5PorterGobbleVC(&zStem[n], nStem-n, 1) ){
return 1;
}
return 0;
}
/* porter rule condition: (m = 1) */
static int fts5Porter_MEq1(char *zStem, int nStem){
int n;
n = fts5PorterGobbleVC(zStem, nStem, 0);
if( n && 0==fts5PorterGobbleVC(&zStem[n], nStem-n, 1) ){
return 1;
}
return 0;
}
/* porter rule condition: (*o) */
static int fts5Porter_Ostar(char *zStem, int nStem){
if( zStem[nStem-1]=='w' || zStem[nStem-1]=='x' || zStem[nStem-1]=='y' ){
return 0;
}else{
int i;
int mask = 0;
int bCons = 0;
for(i=0; i<nStem; i++){
bCons = !fts5PorterIsVowel(zStem[i], bCons);
assert( bCons==0 || bCons==1 );
mask = (mask << 1) + bCons;
}
return ((mask & 0x0007)==0x0005);
}
}
/* porter rule condition: (m > 1 and (*S or *T)) */
static int fts5Porter_MGt1_and_S_or_T(char *zStem, int nStem){
assert( nStem>0 );
return (zStem[nStem-1]=='s' || zStem[nStem-1]=='t')
&& fts5Porter_MGt1(zStem, nStem);
}
/* porter rule condition: (*v*) */
static int fts5Porter_Vowel(char *zStem, int nStem){
int i;
for(i=0; i<nStem; i++){
if( fts5PorterIsVowel(zStem[i], i>0) ){
return 1;
}
}
return 0;
}
/**************************************************************************
***************************************************************************
** GENERATED CODE STARTS HERE (mkportersteps.tcl)
*/
static int fts5PorterStep4(char *aBuf, int *pnBuf){
int ret = 0;
int nBuf = *pnBuf;
switch( aBuf[nBuf-2] ){
case 'a':
if( nBuf>2 && 0==memcmp("al", &aBuf[nBuf-2], 2) ){
if( fts5Porter_MGt1(aBuf, nBuf-2) ){
*pnBuf = nBuf - 2;
}
}
break;
case 'c':
if( nBuf>4 && 0==memcmp("ance", &aBuf[nBuf-4], 4) ){
if( fts5Porter_MGt1(aBuf, nBuf-4) ){
*pnBuf = nBuf - 4;
}
}else if( nBuf>4 && 0==memcmp("ence", &aBuf[nBuf-4], 4) ){
if( fts5Porter_MGt1(aBuf, nBuf-4) ){
*pnBuf = nBuf - 4;
}
}
break;
case 'e':
if( nBuf>2 && 0==memcmp("er", &aBuf[nBuf-2], 2) ){
if( fts5Porter_MGt1(aBuf, nBuf-2) ){
*pnBuf = nBuf - 2;
}
}
break;
case 'i':
if( nBuf>2 && 0==memcmp("ic", &aBuf[nBuf-2], 2) ){
if( fts5Porter_MGt1(aBuf, nBuf-2) ){
*pnBuf = nBuf - 2;
}
}
break;
case 'l':
if( nBuf>4 && 0==memcmp("able", &aBuf[nBuf-4], 4) ){
if( fts5Porter_MGt1(aBuf, nBuf-4) ){
*pnBuf = nBuf - 4;
}
}else if( nBuf>4 && 0==memcmp("ible", &aBuf[nBuf-4], 4) ){
if( fts5Porter_MGt1(aBuf, nBuf-4) ){
*pnBuf = nBuf - 4;
}
}
break;
case 'n':
if( nBuf>3 && 0==memcmp("ant", &aBuf[nBuf-3], 3) ){
if( fts5Porter_MGt1(aBuf, nBuf-3) ){
*pnBuf = nBuf - 3;
}
}else if( nBuf>5 && 0==memcmp("ement", &aBuf[nBuf-5], 5) ){
if( fts5Porter_MGt1(aBuf, nBuf-5) ){
*pnBuf = nBuf - 5;
}
}else if( nBuf>4 && 0==memcmp("ment", &aBuf[nBuf-4], 4) ){
if( fts5Porter_MGt1(aBuf, nBuf-4) ){
*pnBuf = nBuf - 4;
}
}else if( nBuf>3 && 0==memcmp("ent", &aBuf[nBuf-3], 3) ){
if( fts5Porter_MGt1(aBuf, nBuf-3) ){
*pnBuf = nBuf - 3;
}
}
break;
case 'o':
if( nBuf>3 && 0==memcmp("ion", &aBuf[nBuf-3], 3) ){
if( fts5Porter_MGt1_and_S_or_T(aBuf, nBuf-3) ){
*pnBuf = nBuf - 3;
}
}else if( nBuf>2 && 0==memcmp("ou", &aBuf[nBuf-2], 2) ){
if( fts5Porter_MGt1(aBuf, nBuf-2) ){
*pnBuf = nBuf - 2;
}
}
break;
case 's':
if( nBuf>3 && 0==memcmp("ism", &aBuf[nBuf-3], 3) ){
if( fts5Porter_MGt1(aBuf, nBuf-3) ){
*pnBuf = nBuf - 3;
}
}
break;
case 't':
if( nBuf>3 && 0==memcmp("ate", &aBuf[nBuf-3], 3) ){
if( fts5Porter_MGt1(aBuf, nBuf-3) ){
*pnBuf = nBuf - 3;
}
}else if( nBuf>3 && 0==memcmp("iti", &aBuf[nBuf-3], 3) ){
if( fts5Porter_MGt1(aBuf, nBuf-3) ){
*pnBuf = nBuf - 3;
}
}
break;
case 'u':
if( nBuf>3 && 0==memcmp("ous", &aBuf[nBuf-3], 3) ){
if( fts5Porter_MGt1(aBuf, nBuf-3) ){
*pnBuf = nBuf - 3;
}
}
break;
case 'v':
if( nBuf>3 && 0==memcmp("ive", &aBuf[nBuf-3], 3) ){
if( fts5Porter_MGt1(aBuf, nBuf-3) ){
*pnBuf = nBuf - 3;
}
}
break;
case 'z':
if( nBuf>3 && 0==memcmp("ize", &aBuf[nBuf-3], 3) ){
if( fts5Porter_MGt1(aBuf, nBuf-3) ){
*pnBuf = nBuf - 3;
}
}
break;
}
return ret;
}
static int fts5PorterStep1B2(char *aBuf, int *pnBuf){
int ret = 0;
int nBuf = *pnBuf;
switch( aBuf[nBuf-2] ){
case 'a':
if( nBuf>2 && 0==memcmp("at", &aBuf[nBuf-2], 2) ){
memcpy(&aBuf[nBuf-2], "ate", 3);
*pnBuf = nBuf - 2 + 3;
ret = 1;
}
break;
case 'b':
if( nBuf>2 && 0==memcmp("bl", &aBuf[nBuf-2], 2) ){
memcpy(&aBuf[nBuf-2], "ble", 3);
*pnBuf = nBuf - 2 + 3;
ret = 1;
}
break;
case 'i':
if( nBuf>2 && 0==memcmp("iz", &aBuf[nBuf-2], 2) ){
memcpy(&aBuf[nBuf-2], "ize", 3);
*pnBuf = nBuf - 2 + 3;
ret = 1;
}
break;
}
return ret;
}
static int fts5PorterStep2(char *aBuf, int *pnBuf){
int ret = 0;
int nBuf = *pnBuf;
switch( aBuf[nBuf-2] ){
case 'a':
if( nBuf>7 && 0==memcmp("ational", &aBuf[nBuf-7], 7) ){
if( fts5Porter_MGt0(aBuf, nBuf-7) ){
memcpy(&aBuf[nBuf-7], "ate", 3);
*pnBuf = nBuf - 7 + 3;
}
}else if( nBuf>6 && 0==memcmp("tional", &aBuf[nBuf-6], 6) ){
if( fts5Porter_MGt0(aBuf, nBuf-6) ){
memcpy(&aBuf[nBuf-6], "tion", 4);
*pnBuf = nBuf - 6 + 4;
}
}
break;
case 'c':
if( nBuf>4 && 0==memcmp("enci", &aBuf[nBuf-4], 4) ){
if( fts5Porter_MGt0(aBuf, nBuf-4) ){
memcpy(&aBuf[nBuf-4], "ence", 4);
*pnBuf = nBuf - 4 + 4;
}
}else if( nBuf>4 && 0==memcmp("anci", &aBuf[nBuf-4], 4) ){
if( fts5Porter_MGt0(aBuf, nBuf-4) ){
memcpy(&aBuf[nBuf-4], "ance", 4);
*pnBuf = nBuf - 4 + 4;
}
}
break;
case 'e':
if( nBuf>4 && 0==memcmp("izer", &aBuf[nBuf-4], 4) ){
if( fts5Porter_MGt0(aBuf, nBuf-4) ){
memcpy(&aBuf[nBuf-4], "ize", 3);
*pnBuf = nBuf - 4 + 3;
}
}
break;
case 'g':
if( nBuf>4 && 0==memcmp("logi", &aBuf[nBuf-4], 4) ){
if( fts5Porter_MGt0(aBuf, nBuf-4) ){
memcpy(&aBuf[nBuf-4], "log", 3);
*pnBuf = nBuf - 4 + 3;
}
}
break;
case 'l':
if( nBuf>3 && 0==memcmp("bli", &aBuf[nBuf-3], 3) ){
if( fts5Porter_MGt0(aBuf, nBuf-3) ){
memcpy(&aBuf[nBuf-3], "ble", 3);
*pnBuf = nBuf - 3 + 3;
}
}else if( nBuf>4 && 0==memcmp("alli", &aBuf[nBuf-4], 4) ){
if( fts5Porter_MGt0(aBuf, nBuf-4) ){
memcpy(&aBuf[nBuf-4], "al", 2);
*pnBuf = nBuf - 4 + 2;
}
}else if( nBuf>5 && 0==memcmp("entli", &aBuf[nBuf-5], 5) ){
if( fts5Porter_MGt0(aBuf, nBuf-5) ){
memcpy(&aBuf[nBuf-5], "ent", 3);
*pnBuf = nBuf - 5 + 3;
}
}else if( nBuf>3 && 0==memcmp("eli", &aBuf[nBuf-3], 3) ){
if( fts5Porter_MGt0(aBuf, nBuf-3) ){
memcpy(&aBuf[nBuf-3], "e", 1);
*pnBuf = nBuf - 3 + 1;
}
}else if( nBuf>5 && 0==memcmp("ousli", &aBuf[nBuf-5], 5) ){
if( fts5Porter_MGt0(aBuf, nBuf-5) ){
memcpy(&aBuf[nBuf-5], "ous", 3);
*pnBuf = nBuf - 5 + 3;
}
}
break;
case 'o':
if( nBuf>7 && 0==memcmp("ization", &aBuf[nBuf-7], 7) ){
if( fts5Porter_MGt0(aBuf, nBuf-7) ){
memcpy(&aBuf[nBuf-7], "ize", 3);
*pnBuf = nBuf - 7 + 3;
}
}else if( nBuf>5 && 0==memcmp("ation", &aBuf[nBuf-5], 5) ){
if( fts5Porter_MGt0(aBuf, nBuf-5) ){
memcpy(&aBuf[nBuf-5], "ate", 3);
*pnBuf = nBuf - 5 + 3;
}
}else if( nBuf>4 && 0==memcmp("ator", &aBuf[nBuf-4], 4) ){
if( fts5Porter_MGt0(aBuf, nBuf-4) ){
memcpy(&aBuf[nBuf-4], "ate", 3);
*pnBuf = nBuf - 4 + 3;
}
}
break;
case 's':
if( nBuf>5 && 0==memcmp("alism", &aBuf[nBuf-5], 5) ){
if( fts5Porter_MGt0(aBuf, nBuf-5) ){
memcpy(&aBuf[nBuf-5], "al", 2);
*pnBuf = nBuf - 5 + 2;
}
}else if( nBuf>7 && 0==memcmp("iveness", &aBuf[nBuf-7], 7) ){
if( fts5Porter_MGt0(aBuf, nBuf-7) ){
memcpy(&aBuf[nBuf-7], "ive", 3);
*pnBuf = nBuf - 7 + 3;
}
}else if( nBuf>7 && 0==memcmp("fulness", &aBuf[nBuf-7], 7) ){
if( fts5Porter_MGt0(aBuf, nBuf-7) ){
memcpy(&aBuf[nBuf-7], "ful", 3);
*pnBuf = nBuf - 7 + 3;
}
}else if( nBuf>7 && 0==memcmp("ousness", &aBuf[nBuf-7], 7) ){
if( fts5Porter_MGt0(aBuf, nBuf-7) ){
memcpy(&aBuf[nBuf-7], "ous", 3);
*pnBuf = nBuf - 7 + 3;
}
}
break;
case 't':
if( nBuf>5 && 0==memcmp("aliti", &aBuf[nBuf-5], 5) ){
if( fts5Porter_MGt0(aBuf, nBuf-5) ){
memcpy(&aBuf[nBuf-5], "al", 2);
*pnBuf = nBuf - 5 + 2;
}
}else if( nBuf>5 && 0==memcmp("iviti", &aBuf[nBuf-5], 5) ){
if( fts5Porter_MGt0(aBuf, nBuf-5) ){
memcpy(&aBuf[nBuf-5], "ive", 3);
*pnBuf = nBuf - 5 + 3;
}
}else if( nBuf>6 && 0==memcmp("biliti", &aBuf[nBuf-6], 6) ){
if( fts5Porter_MGt0(aBuf, nBuf-6) ){
memcpy(&aBuf[nBuf-6], "ble", 3);
*pnBuf = nBuf - 6 + 3;
}
}
break;
}
return ret;
}
static int fts5PorterStep3(char *aBuf, int *pnBuf){
int ret = 0;
int nBuf = *pnBuf;
switch( aBuf[nBuf-2] ){
case 'a':
if( nBuf>4 && 0==memcmp("ical", &aBuf[nBuf-4], 4) ){
if( fts5Porter_MGt0(aBuf, nBuf-4) ){
memcpy(&aBuf[nBuf-4], "ic", 2);
*pnBuf = nBuf - 4 + 2;
}
}
break;
case 's':
if( nBuf>4 && 0==memcmp("ness", &aBuf[nBuf-4], 4) ){
if( fts5Porter_MGt0(aBuf, nBuf-4) ){
*pnBuf = nBuf - 4;
}
}
break;
case 't':
if( nBuf>5 && 0==memcmp("icate", &aBuf[nBuf-5], 5) ){
if( fts5Porter_MGt0(aBuf, nBuf-5) ){
memcpy(&aBuf[nBuf-5], "ic", 2);
*pnBuf = nBuf - 5 + 2;
}
}else if( nBuf>5 && 0==memcmp("iciti", &aBuf[nBuf-5], 5) ){
if( fts5Porter_MGt0(aBuf, nBuf-5) ){
memcpy(&aBuf[nBuf-5], "ic", 2);
*pnBuf = nBuf - 5 + 2;
}
}
break;
case 'u':
if( nBuf>3 && 0==memcmp("ful", &aBuf[nBuf-3], 3) ){
if( fts5Porter_MGt0(aBuf, nBuf-3) ){
*pnBuf = nBuf - 3;
}
}
break;
case 'v':
if( nBuf>5 && 0==memcmp("ative", &aBuf[nBuf-5], 5) ){
if( fts5Porter_MGt0(aBuf, nBuf-5) ){
*pnBuf = nBuf - 5;
}
}
break;
case 'z':
if( nBuf>5 && 0==memcmp("alize", &aBuf[nBuf-5], 5) ){
if( fts5Porter_MGt0(aBuf, nBuf-5) ){
memcpy(&aBuf[nBuf-5], "al", 2);
*pnBuf = nBuf - 5 + 2;
}
}
break;
}
return ret;
}
static int fts5PorterStep1B(char *aBuf, int *pnBuf){
int ret = 0;
int nBuf = *pnBuf;
switch( aBuf[nBuf-2] ){
case 'e':
if( nBuf>3 && 0==memcmp("eed", &aBuf[nBuf-3], 3) ){
if( fts5Porter_MGt0(aBuf, nBuf-3) ){
memcpy(&aBuf[nBuf-3], "ee", 2);
*pnBuf = nBuf - 3 + 2;
}
}else if( nBuf>2 && 0==memcmp("ed", &aBuf[nBuf-2], 2) ){
if( fts5Porter_Vowel(aBuf, nBuf-2) ){
*pnBuf = nBuf - 2;
ret = 1;
}
}
break;
case 'n':
if( nBuf>3 && 0==memcmp("ing", &aBuf[nBuf-3], 3) ){
if( fts5Porter_Vowel(aBuf, nBuf-3) ){
*pnBuf = nBuf - 3;
ret = 1;
}
}
break;
}
return ret;
}
/*
** GENERATED CODE ENDS HERE (mkportersteps.tcl)
***************************************************************************
**************************************************************************/
static void fts5PorterStep1A(char *aBuf, int *pnBuf){
int nBuf = *pnBuf;
if( aBuf[nBuf-1]=='s' ){
if( aBuf[nBuf-2]=='e' ){
if( (nBuf>4 && aBuf[nBuf-4]=='s' && aBuf[nBuf-3]=='s')
|| (nBuf>3 && aBuf[nBuf-3]=='i' )
){
*pnBuf = nBuf-2;
}else{
*pnBuf = nBuf-1;
}
}
else if( aBuf[nBuf-2]!='s' ){
*pnBuf = nBuf-1;
}
}
}
static int fts5PorterCb(
void *pCtx,
int tflags,
const char *pToken,
int nToken,
int iStart,
int iEnd
){
PorterContext *p = (PorterContext*)pCtx;
char *aBuf;
int nBuf;
if( nToken>FTS5_PORTER_MAX_TOKEN || nToken<3 ) goto pass_through;
aBuf = p->aBuf;
nBuf = nToken;
memcpy(aBuf, pToken, nBuf);
/* Step 1. */
fts5PorterStep1A(aBuf, &nBuf);
if( fts5PorterStep1B(aBuf, &nBuf) ){
if( fts5PorterStep1B2(aBuf, &nBuf)==0 ){
char c = aBuf[nBuf-1];
if( fts5PorterIsVowel(c, 0)==0
&& c!='l' && c!='s' && c!='z' && c==aBuf[nBuf-2]
){
nBuf--;
}else if( fts5Porter_MEq1(aBuf, nBuf) && fts5Porter_Ostar(aBuf, nBuf) ){
aBuf[nBuf++] = 'e';
}
}
}
/* Step 1C. */
if( aBuf[nBuf-1]=='y' && fts5Porter_Vowel(aBuf, nBuf-1) ){
aBuf[nBuf-1] = 'i';
}
/* Steps 2 through 4. */
fts5PorterStep2(aBuf, &nBuf);
fts5PorterStep3(aBuf, &nBuf);
fts5PorterStep4(aBuf, &nBuf);
/* Step 5a. */
assert( nBuf>0 );
if( aBuf[nBuf-1]=='e' ){
if( fts5Porter_MGt1(aBuf, nBuf-1)
|| (fts5Porter_MEq1(aBuf, nBuf-1) && !fts5Porter_Ostar(aBuf, nBuf-1))
){
nBuf--;
}
}
/* Step 5b. */
if( nBuf>1 && aBuf[nBuf-1]=='l'
&& aBuf[nBuf-2]=='l' && fts5Porter_MGt1(aBuf, nBuf-1)
){
nBuf--;
}
return p->xToken(p->pCtx, tflags, aBuf, nBuf, iStart, iEnd);
pass_through:
return p->xToken(p->pCtx, tflags, pToken, nToken, iStart, iEnd);
}
/*
** Tokenize using the porter tokenizer.
*/
static int fts5PorterTokenize(
Fts5Tokenizer *pTokenizer,
void *pCtx,
int flags,
const char *pText, int nText,
int (*xToken)(void*, int, const char*, int nToken, int iStart, int iEnd)
){
PorterTokenizer *p = (PorterTokenizer*)pTokenizer;
PorterContext sCtx;
sCtx.xToken = xToken;
sCtx.pCtx = pCtx;
sCtx.aBuf = p->aBuf;
return p->tokenizer.xTokenize(
p->pTokenizer, (void*)&sCtx, flags, pText, nText, fts5PorterCb
);
}
/**************************************************************************
** Start of trigram implementation.
*/
typedef struct TrigramTokenizer TrigramTokenizer;
struct TrigramTokenizer {
int bFold; /* True to fold to lower-case */
};
/*
** Free a trigram tokenizer.
*/
static void fts5TriDelete(Fts5Tokenizer *p){
sqlite3_free(p);
}
/*
** Allocate a trigram tokenizer.
*/
static int fts5TriCreate(
void *pUnused,
const char **azArg,
int nArg,
Fts5Tokenizer **ppOut
){
int rc = SQLITE_OK;
TrigramTokenizer *pNew = (TrigramTokenizer*)sqlite3_malloc(sizeof(*pNew));
UNUSED_PARAM(pUnused);
if( pNew==0 ){
rc = SQLITE_NOMEM;
}else{
int i;
pNew->bFold = 1;
for(i=0; rc==SQLITE_OK && i<nArg; i+=2){
const char *zArg = azArg[i+1];
if( 0==sqlite3_stricmp(azArg[i], "case_sensitive") ){
if( (zArg[0]!='0' && zArg[0]!='1') || zArg[1] ){
rc = SQLITE_ERROR;
}else{
pNew->bFold = (zArg[0]=='0');
}
}else{
rc = SQLITE_ERROR;
}
}
if( rc!=SQLITE_OK ){
fts5TriDelete((Fts5Tokenizer*)pNew);
pNew = 0;
}
}
*ppOut = (Fts5Tokenizer*)pNew;
return rc;
}
/*
** Trigram tokenizer tokenize routine.
*/
static int fts5TriTokenize(
Fts5Tokenizer *pTok,
void *pCtx,
int unusedFlags,
const char *pText, int nText,
int (*xToken)(void*, int, const char*, int, int, int)
){
TrigramTokenizer *p = (TrigramTokenizer*)pTok;
int rc = SQLITE_OK;
char aBuf[32];
const unsigned char *zIn = (const unsigned char*)pText;
const unsigned char *zEof = &zIn[nText];
u32 iCode;
UNUSED_PARAM(unusedFlags);
while( 1 ){
char *zOut = aBuf;
int iStart = zIn - (const unsigned char*)pText;
const unsigned char *zNext;
READ_UTF8(zIn, zEof, iCode);
if( iCode==0 ) break;
zNext = zIn;
if( zIn<zEof ){
if( p->bFold ) iCode = sqlite3Fts5UnicodeFold(iCode, 0);
WRITE_UTF8(zOut, iCode);
READ_UTF8(zIn, zEof, iCode);
if( iCode==0 ) break;
}else{
break;
}
if( zIn<zEof ){
if( p->bFold ) iCode = sqlite3Fts5UnicodeFold(iCode, 0);
WRITE_UTF8(zOut, iCode);
READ_UTF8(zIn, zEof, iCode);
if( iCode==0 ) break;
if( p->bFold ) iCode = sqlite3Fts5UnicodeFold(iCode, 0);
WRITE_UTF8(zOut, iCode);
}else{
break;
}
rc = xToken(pCtx, 0, aBuf, zOut-aBuf, iStart, iStart + zOut-aBuf);
if( rc!=SQLITE_OK ) break;
zIn = zNext;
}
return rc;
}
/*
** Argument xCreate is a pointer to a constructor function for a tokenizer.
** pTok is a tokenizer previously created using the same method. This function
** returns one of FTS5_PATTERN_NONE, FTS5_PATTERN_LIKE or FTS5_PATTERN_GLOB
** indicating the style of pattern matching that the tokenizer can support.
** In practice, this is:
**
** "trigram" tokenizer, case_sensitive=1 - FTS5_PATTERN_GLOB
** "trigram" tokenizer, case_sensitive=0 (the default) - FTS5_PATTERN_LIKE
** all other tokenizers - FTS5_PATTERN_NONE
*/
int sqlite3Fts5TokenizerPattern(
int (*xCreate)(void*, const char**, int, Fts5Tokenizer**),
Fts5Tokenizer *pTok
){
if( xCreate==fts5TriCreate ){
TrigramTokenizer *p = (TrigramTokenizer*)pTok;
return p->bFold ? FTS5_PATTERN_LIKE : FTS5_PATTERN_GLOB;
}
return FTS5_PATTERN_NONE;
}
/*
** Register all built-in tokenizers with FTS5.
*/
int sqlite3Fts5TokenizerInit(fts5_api *pApi){
struct BuiltinTokenizer {
const char *zName;
fts5_tokenizer x;
} aBuiltin[] = {
{ "unicode61", {fts5UnicodeCreate, fts5UnicodeDelete, fts5UnicodeTokenize}},
{ "ascii", {fts5AsciiCreate, fts5AsciiDelete, fts5AsciiTokenize }},
{ "porter", {fts5PorterCreate, fts5PorterDelete, fts5PorterTokenize }},
{ "trigram", {fts5TriCreate, fts5TriDelete, fts5TriTokenize}},
};
int rc = SQLITE_OK; /* Return code */
int i; /* To iterate through builtin functions */
for(i=0; rc==SQLITE_OK && i<ArraySize(aBuiltin); i++){
rc = pApi->xCreateTokenizer(pApi,
aBuiltin[i].zName,
(void*)pApi,
&aBuiltin[i].x,
0
);
}
return rc;
}