262 lines
6.6 KiB
C
262 lines
6.6 KiB
C
/*
|
|
** 2007 June 22
|
|
**
|
|
** 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 file implements a tokenizer for fts3 based on the ICU library.
|
|
*/
|
|
#include "fts3Int.h"
|
|
#if !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_FTS3)
|
|
#ifdef SQLITE_ENABLE_ICU
|
|
|
|
#include <assert.h>
|
|
#include <string.h>
|
|
#include "fts3_tokenizer.h"
|
|
|
|
#include <unicode/ubrk.h>
|
|
#include <unicode/ucol.h>
|
|
#include <unicode/ustring.h>
|
|
#include <unicode/utf16.h>
|
|
|
|
typedef struct IcuTokenizer IcuTokenizer;
|
|
typedef struct IcuCursor IcuCursor;
|
|
|
|
struct IcuTokenizer {
|
|
sqlite3_tokenizer base;
|
|
char *zLocale;
|
|
};
|
|
|
|
struct IcuCursor {
|
|
sqlite3_tokenizer_cursor base;
|
|
|
|
UBreakIterator *pIter; /* ICU break-iterator object */
|
|
int nChar; /* Number of UChar elements in pInput */
|
|
UChar *aChar; /* Copy of input using utf-16 encoding */
|
|
int *aOffset; /* Offsets of each character in utf-8 input */
|
|
|
|
int nBuffer;
|
|
char *zBuffer;
|
|
|
|
int iToken;
|
|
};
|
|
|
|
/*
|
|
** Create a new tokenizer instance.
|
|
*/
|
|
static int icuCreate(
|
|
int argc, /* Number of entries in argv[] */
|
|
const char * const *argv, /* Tokenizer creation arguments */
|
|
sqlite3_tokenizer **ppTokenizer /* OUT: Created tokenizer */
|
|
){
|
|
IcuTokenizer *p;
|
|
int n = 0;
|
|
|
|
if( argc>0 ){
|
|
n = strlen(argv[0])+1;
|
|
}
|
|
p = (IcuTokenizer *)sqlite3_malloc(sizeof(IcuTokenizer)+n);
|
|
if( !p ){
|
|
return SQLITE_NOMEM;
|
|
}
|
|
memset(p, 0, sizeof(IcuTokenizer));
|
|
|
|
if( n ){
|
|
p->zLocale = (char *)&p[1];
|
|
memcpy(p->zLocale, argv[0], n);
|
|
}
|
|
|
|
*ppTokenizer = (sqlite3_tokenizer *)p;
|
|
|
|
return SQLITE_OK;
|
|
}
|
|
|
|
/*
|
|
** Destroy a tokenizer
|
|
*/
|
|
static int icuDestroy(sqlite3_tokenizer *pTokenizer){
|
|
IcuTokenizer *p = (IcuTokenizer *)pTokenizer;
|
|
sqlite3_free(p);
|
|
return SQLITE_OK;
|
|
}
|
|
|
|
/*
|
|
** Prepare to begin tokenizing a particular string. The input
|
|
** string to be tokenized is pInput[0..nBytes-1]. A cursor
|
|
** used to incrementally tokenize this string is returned in
|
|
** *ppCursor.
|
|
*/
|
|
static int icuOpen(
|
|
sqlite3_tokenizer *pTokenizer, /* The tokenizer */
|
|
const char *zInput, /* Input string */
|
|
int nInput, /* Length of zInput in bytes */
|
|
sqlite3_tokenizer_cursor **ppCursor /* OUT: Tokenization cursor */
|
|
){
|
|
IcuTokenizer *p = (IcuTokenizer *)pTokenizer;
|
|
IcuCursor *pCsr;
|
|
|
|
const int32_t opt = U_FOLD_CASE_DEFAULT;
|
|
UErrorCode status = U_ZERO_ERROR;
|
|
int nChar;
|
|
|
|
UChar32 c;
|
|
int iInput = 0;
|
|
int iOut = 0;
|
|
|
|
*ppCursor = 0;
|
|
|
|
if( zInput==0 ){
|
|
nInput = 0;
|
|
zInput = "";
|
|
}else if( nInput<0 ){
|
|
nInput = strlen(zInput);
|
|
}
|
|
nChar = nInput+1;
|
|
pCsr = (IcuCursor *)sqlite3_malloc(
|
|
sizeof(IcuCursor) + /* IcuCursor */
|
|
((nChar+3)&~3) * sizeof(UChar) + /* IcuCursor.aChar[] */
|
|
(nChar+1) * sizeof(int) /* IcuCursor.aOffset[] */
|
|
);
|
|
if( !pCsr ){
|
|
return SQLITE_NOMEM;
|
|
}
|
|
memset(pCsr, 0, sizeof(IcuCursor));
|
|
pCsr->aChar = (UChar *)&pCsr[1];
|
|
pCsr->aOffset = (int *)&pCsr->aChar[(nChar+3)&~3];
|
|
|
|
pCsr->aOffset[iOut] = iInput;
|
|
U8_NEXT(zInput, iInput, nInput, c);
|
|
while( c>0 ){
|
|
int isError = 0;
|
|
c = u_foldCase(c, opt);
|
|
U16_APPEND(pCsr->aChar, iOut, nChar, c, isError);
|
|
if( isError ){
|
|
sqlite3_free(pCsr);
|
|
return SQLITE_ERROR;
|
|
}
|
|
pCsr->aOffset[iOut] = iInput;
|
|
|
|
if( iInput<nInput ){
|
|
U8_NEXT(zInput, iInput, nInput, c);
|
|
}else{
|
|
c = 0;
|
|
}
|
|
}
|
|
|
|
pCsr->pIter = ubrk_open(UBRK_WORD, p->zLocale, pCsr->aChar, iOut, &status);
|
|
if( !U_SUCCESS(status) ){
|
|
sqlite3_free(pCsr);
|
|
return SQLITE_ERROR;
|
|
}
|
|
pCsr->nChar = iOut;
|
|
|
|
ubrk_first(pCsr->pIter);
|
|
*ppCursor = (sqlite3_tokenizer_cursor *)pCsr;
|
|
return SQLITE_OK;
|
|
}
|
|
|
|
/*
|
|
** Close a tokenization cursor previously opened by a call to icuOpen().
|
|
*/
|
|
static int icuClose(sqlite3_tokenizer_cursor *pCursor){
|
|
IcuCursor *pCsr = (IcuCursor *)pCursor;
|
|
ubrk_close(pCsr->pIter);
|
|
sqlite3_free(pCsr->zBuffer);
|
|
sqlite3_free(pCsr);
|
|
return SQLITE_OK;
|
|
}
|
|
|
|
/*
|
|
** Extract the next token from a tokenization cursor.
|
|
*/
|
|
static int icuNext(
|
|
sqlite3_tokenizer_cursor *pCursor, /* Cursor returned by simpleOpen */
|
|
const char **ppToken, /* OUT: *ppToken is the token text */
|
|
int *pnBytes, /* OUT: Number of bytes in token */
|
|
int *piStartOffset, /* OUT: Starting offset of token */
|
|
int *piEndOffset, /* OUT: Ending offset of token */
|
|
int *piPosition /* OUT: Position integer of token */
|
|
){
|
|
IcuCursor *pCsr = (IcuCursor *)pCursor;
|
|
|
|
int iStart = 0;
|
|
int iEnd = 0;
|
|
int nByte = 0;
|
|
|
|
while( iStart==iEnd ){
|
|
UChar32 c;
|
|
|
|
iStart = ubrk_current(pCsr->pIter);
|
|
iEnd = ubrk_next(pCsr->pIter);
|
|
if( iEnd==UBRK_DONE ){
|
|
return SQLITE_DONE;
|
|
}
|
|
|
|
while( iStart<iEnd ){
|
|
int iWhite = iStart;
|
|
U16_NEXT(pCsr->aChar, iWhite, pCsr->nChar, c);
|
|
if( u_isspace(c) ){
|
|
iStart = iWhite;
|
|
}else{
|
|
break;
|
|
}
|
|
}
|
|
assert(iStart<=iEnd);
|
|
}
|
|
|
|
do {
|
|
UErrorCode status = U_ZERO_ERROR;
|
|
if( nByte ){
|
|
char *zNew = sqlite3_realloc(pCsr->zBuffer, nByte);
|
|
if( !zNew ){
|
|
return SQLITE_NOMEM;
|
|
}
|
|
pCsr->zBuffer = zNew;
|
|
pCsr->nBuffer = nByte;
|
|
}
|
|
|
|
u_strToUTF8(
|
|
pCsr->zBuffer, pCsr->nBuffer, &nByte, /* Output vars */
|
|
&pCsr->aChar[iStart], iEnd-iStart, /* Input vars */
|
|
&status /* Output success/failure */
|
|
);
|
|
} while( nByte>pCsr->nBuffer );
|
|
|
|
*ppToken = pCsr->zBuffer;
|
|
*pnBytes = nByte;
|
|
*piStartOffset = pCsr->aOffset[iStart];
|
|
*piEndOffset = pCsr->aOffset[iEnd];
|
|
*piPosition = pCsr->iToken++;
|
|
|
|
return SQLITE_OK;
|
|
}
|
|
|
|
/*
|
|
** The set of routines that implement the simple tokenizer
|
|
*/
|
|
static const sqlite3_tokenizer_module icuTokenizerModule = {
|
|
0, /* iVersion */
|
|
icuCreate, /* xCreate */
|
|
icuDestroy, /* xCreate */
|
|
icuOpen, /* xOpen */
|
|
icuClose, /* xClose */
|
|
icuNext, /* xNext */
|
|
};
|
|
|
|
/*
|
|
** Set *ppModule to point at the implementation of the ICU tokenizer.
|
|
*/
|
|
void sqlite3Fts3IcuTokenizerModule(
|
|
sqlite3_tokenizer_module const**ppModule
|
|
){
|
|
*ppModule = &icuTokenizerModule;
|
|
}
|
|
|
|
#endif /* defined(SQLITE_ENABLE_ICU) */
|
|
#endif /* !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_FTS3) */
|