void sqlite3Fts3Matchinfo(
  sqlite3_context *pContext,      /* Function call context */
  Fts3Cursor *pCsr,               /* FTS3 table cursor */
  const char *zArg                /* Second arg to matchinfo() function */
){
  Fts3Table *pTab = (Fts3Table *)pCsr->base.pVtab;
  int rc;
  int i;
  const char *zFormat;

  if( zArg ){
    for(i=0; zArg[i]; i++){
      char *zErr = 0;
      if( fts3MatchinfoCheck(pTab, zArg[i], &zErr) ){
        sqlite3_result_error(pContext, zErr, -1);
        sqlite3_free(zErr);
        return;
      }
    }
    zFormat = zArg;
  }else{
    zFormat = FTS3_MATCHINFO_DEFAULT;
  }

  if( !pCsr->pExpr ){
    sqlite3_result_blob(pContext, "", 0, SQLITE_STATIC);
    return;
  }

  /* Retrieve matchinfo() data. */
  rc = fts3GetMatchinfo(pCsr, zFormat);
  sqlite3Fts3SegmentsClose(pTab);

  if( rc!=SQLITE_OK ){
    sqlite3_result_error_code(pContext, rc);
  }else{
    int n = pCsr->nMatchinfo * sizeof(u32);
    sqlite3_result_blob(pContext, pCsr->aMatchinfo, n, SQLITE_TRANSIENT);
  }
}
Unknown