static std::string getText(Cell const& cell)
{
if (cell.hasExpression && !cell.expression.empty())
return "=" + exprToString(cell.expression);
return cell.text;
}
/*
** Return a pointer to a buffer containing a text representation of the
** expression passed as the first argument. The buffer is obtained from
** sqlite3_malloc(). It is the responsibility of the caller to use
** sqlite3_free() to release the memory. If an OOM condition is encountered,
** NULL is returned.
**
** If the second argument is not NULL, then its contents are prepended to
** the returned expression text and then freed using sqlite3_free().
*/
static char *exprToString(Fts3Expr *pExpr, char *zBuf){
if( pExpr==0 ){
return sqlite3_mprintf("");
}
switch( pExpr->eType ){
case FTSQUERY_PHRASE: {
Fts3Phrase *pPhrase = pExpr->pPhrase;
int i;
zBuf = sqlite3_mprintf(
"%zPHRASE %d 0", zBuf, pPhrase->iColumn);
for(i=0; zBuf && i<pPhrase->nToken; i++){
zBuf = sqlite3_mprintf("%z %.*s%s", zBuf,
pPhrase->aToken[i].n, pPhrase->aToken[i].z,
(pPhrase->aToken[i].isPrefix?"+":"")
);
}
return zBuf;
}
case FTSQUERY_NEAR:
zBuf = sqlite3_mprintf("%zNEAR/%d ", zBuf, pExpr->nNear);
break;
case FTSQUERY_NOT:
zBuf = sqlite3_mprintf("%zNOT ", zBuf);
break;
case FTSQUERY_AND:
zBuf = sqlite3_mprintf("%zAND ", zBuf);
break;
case FTSQUERY_OR:
zBuf = sqlite3_mprintf("%zOR ", zBuf);
break;
}
if( zBuf ) zBuf = sqlite3_mprintf("%z{", zBuf);
if( zBuf ) zBuf = exprToString(pExpr->pLeft, zBuf);
if( zBuf ) zBuf = sqlite3_mprintf("%z} {", zBuf);
if( zBuf ) zBuf = exprToString(pExpr->pRight, zBuf);
if( zBuf ) zBuf = sqlite3_mprintf("%z}", zBuf);
return zBuf;
}
/*
** This function is part of the test interface for the query parser. It
** writes a text representation of the query expression pExpr into the
** buffer pointed to by argument zBuf. It is assumed that zBuf is large
** enough to store the required text representation.
*/
static void exprToString(Fts3Expr *pExpr, char *zBuf){
switch( pExpr->eType ){
case FTSQUERY_PHRASE: {
Fts3Phrase *pPhrase = pExpr->pPhrase;
int i;
zBuf += sprintf(zBuf, "PHRASE %d %d", pPhrase->iColumn, pPhrase->isNot);
for(i=0; i<pPhrase->nToken; i++){
zBuf += sprintf(zBuf," %.*s",pPhrase->aToken[i].n,pPhrase->aToken[i].z);
zBuf += sprintf(zBuf,"%s", (pPhrase->aToken[i].isPrefix?"+":""));
}
return;
}
case FTSQUERY_NEAR:
zBuf += sprintf(zBuf, "NEAR/%d ", pExpr->nNear);
break;
case FTSQUERY_NOT:
zBuf += sprintf(zBuf, "NOT ");
break;
case FTSQUERY_AND:
zBuf += sprintf(zBuf, "AND ");
break;
case FTSQUERY_OR:
zBuf += sprintf(zBuf, "OR ");
break;
}
zBuf += sprintf(zBuf, "{");
exprToString(pExpr->pLeft, zBuf);
zBuf += strlen(zBuf);
zBuf += sprintf(zBuf, "} ");
zBuf += sprintf(zBuf, "{");
exprToString(pExpr->pRight, zBuf);
zBuf += strlen(zBuf);
zBuf += sprintf(zBuf, "}");
}
/*
** This is the implementation of a scalar SQL function used to test the
** expression parser. It should be called as follows:
**
** fts3_exprtest(<tokenizer>, <expr>, <column 1>, ...);
**
** The first argument, <tokenizer>, is the name of the fts3 tokenizer used
** to parse the query expression (see README.tokenizers). The second argument
** is the query expression to parse. Each subsequent argument is the name
** of a column of the fts3 table that the query expression may refer to.
** For example:
**
** SELECT fts3_exprtest('simple', 'Bill col2:Bloggs', 'col1', 'col2');
*/
static void fts3ExprTest(
sqlite3_context *context,
int argc,
sqlite3_value **argv
){
sqlite3_tokenizer_module const *pModule = 0;
sqlite3_tokenizer *pTokenizer = 0;
int rc;
char **azCol = 0;
const char *zExpr;
int nExpr;
int nCol;
int ii;
Fts3Expr *pExpr;
char *zBuf = 0;
sqlite3 *db = sqlite3_context_db_handle(context);
if( argc<3 ){
sqlite3_result_error(context,
"Usage: fts3_exprtest(tokenizer, expr, col1, ...", -1
);
return;
}
rc = queryTestTokenizer(db,
(const char *)sqlite3_value_text(argv[0]), &pModule);
if( rc==SQLITE_NOMEM ){
sqlite3_result_error_nomem(context);
goto exprtest_out;
}else if( !pModule ){
sqlite3_result_error(context, "No such tokenizer module", -1);
goto exprtest_out;
}
rc = pModule->xCreate(0, 0, &pTokenizer);
assert( rc==SQLITE_NOMEM || rc==SQLITE_OK );
if( rc==SQLITE_NOMEM ){
sqlite3_result_error_nomem(context);
goto exprtest_out;
}
pTokenizer->pModule = pModule;
zExpr = (const char *)sqlite3_value_text(argv[1]);
nExpr = sqlite3_value_bytes(argv[1]);
nCol = argc-2;
azCol = (char **)sqlite3_malloc(nCol*sizeof(char *));
if( !azCol ){
sqlite3_result_error_nomem(context);
goto exprtest_out;
}
for(ii=0; ii<nCol; ii++){
azCol[ii] = (char *)sqlite3_value_text(argv[ii+2]);
}
rc = sqlite3Fts3ExprParse(
pTokenizer, azCol, nCol, nCol, zExpr, nExpr, &pExpr
);
if( rc!=SQLITE_OK && rc!=SQLITE_NOMEM ){
sqlite3_result_error(context, "Error parsing expression", -1);
}else if( rc==SQLITE_NOMEM || !(zBuf = exprToString(pExpr, 0)) ){
sqlite3_result_error_nomem(context);
}else{
sqlite3_result_text(context, zBuf, -1, SQLITE_TRANSIENT);
sqlite3_free(zBuf);
}
sqlite3Fts3ExprFree(pExpr);
exprtest_out:
if( pModule && pTokenizer ){
rc = pModule->xDestroy(pTokenizer);
}
sqlite3_free(azCol);
}
