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-rw-r--r--ext/fts5/fts5_tokenize.c1415
1 files changed, 1415 insertions, 0 deletions
diff --git a/ext/fts5/fts5_tokenize.c b/ext/fts5/fts5_tokenize.c
new file mode 100644
index 0000000..e61d6b1
--- /dev/null
+++ b/ext/fts5/fts5_tokenize.c
@@ -0,0 +1,1415 @@
+/*
+** 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;
+}
generated by cgit v1.2.3 (git 2.39.1) at 2025-01-01 20:18:02 +0000