SQLite

  int argc,
  sqlite3_value **argv
){
  int i;
  int inStr = 0;
  char *z;
  JsonString *pStr;
  UNUSED_PARAM(argc);
  UNUSED_PARAM(argv);
  pStr = (JsonString*)sqlite3_aggregate_context(ctx, 0);
#ifdef NEVER
  /* pStr is always non-NULL since jsonArrayStep() or jsonObjectStep() will
  ** always have been called to initalize it */
  if( NEVER(!pStr) ) return;
#endif
  z = pStr->zBuf;

      sqlite3_result_value(context, pRes);
    }
    if( bValue==0 ) sqlite3VdbeMemRelease(pRes);
  }
}
#ifndef SQLITE_OMIT_WINDOWFUNC
static void minMaxValue(sqlite3_context *context){
  minMaxValueFinalize(context, 1);
}
#else
# define minMaxValue 0
#endif /* SQLITE_OMIT_WINDOWFUNC */
static void minMaxFinalize(sqlite3_context *context){
  minMaxValueFinalize(context, 0);
}

/*
** group_concat(EXPR, ?SEPARATOR?)
*/
static void groupConcatStep(
  sqlite3_context *context,

#ifndef SQLITE_OMIT_WINDOWFUNC
static void groupConcatInverse(
  sqlite3_context *context,
  int argc,
  sqlite3_value **argv
){
  int n;

  StrAccum *pAccum;
  assert( argc==1 || argc==2 );
  if( sqlite3_value_type(argv[0])==SQLITE_NULL ) return;
  pAccum = (StrAccum*)sqlite3_aggregate_context(context, sizeof(*pAccum));
  /* pAccum is always non-NULL since groupConcatStep() will have always
  ** run frist to initialize it */
  if( ALWAYS(pAccum) ){
    n = sqlite3_value_bytes(argv[0]);
    if( argc==2 ){
      n += sqlite3_value_bytes(argv[1]);
    }else{
      n++;
    }
    if( n>=(int)pAccum->nChar ){
      pAccum->nChar = 0;
    }else{
      pAccum->nChar -= n;
      memmove(pAccum->zText, &pAccum->zText[n], pAccum->nChar);
    }
    if( pAccum->nChar==0 ) pAccum->mxAlloc = 0;
  }

  
  /* Check if an existing function is being overridden or deleted. If so,
  ** and there are active VMs, then return SQLITE_BUSY. If a function
  ** is being overridden/deleted but there are no active VMs, allow the
  ** operation to continue but invalidate all precompiled statements.
  */
  p = sqlite3FindFunction(db, zFunctionName, nArg, (u8)enc, 0);
  if( p && (p->funcFlags & SQLITE_FUNC_ENCMASK)==(u32)enc && p->nArg==nArg ){
    if( db->nVdbeActive ){
      sqlite3ErrorWithMsg(db, SQLITE_BUSY, 
        "unable to delete/modify user-function due to active statements");
      assert( !db->mallocFailed );
      return SQLITE_BUSY;
    }else{
      sqlite3ExpirePreparedStatements(db);

  A = sqlite3SelectNew(pParse,W,X,Y,P,Q,Z,D,L);
#ifndef SQLITE_OMIT_WINDOWFUNC
  if( A ){
    A->pWinDefn = R;
  }else{
    sqlite3WindowListDelete(pParse->db, R);
  }
#endif /* SQLITE_OMIT_WINDOWFUNC */
#if SELECTTRACE_ENABLED
  /* Populate the Select.zSelName[] string that is used to help with
  ** query planner debugging, to differentiate between multiple Select
  ** objects in a complex query.
  **
  ** If the SELECT keyword is immediately followed by a C-style comment
  ** then extract the first few alphanumeric characters from within that

  }else{
    sqlite3ExprDelete(pParse->db, W);
  }
}

filter_opt(A) ::= .                            { A = 0; }
filter_opt(A) ::= FILTER LP WHERE expr(X) RP.  { A = X; }
%endif /* SQLITE_OMIT_WINDOWFUNC */

}
static int analyzeFilterKeyword(const unsigned char *z, int lastToken){
  if( lastToken==TK_RP && getToken(&z)==TK_LP ){
    return TK_FILTER;
  }
  return TK_ID;
}
#endif /* SQLITE_OMIT_WINDOWFUNC */

/*
** Return the length (in bytes) of the token that begins at z[0]. 
** Store the token type in *tokenType before returning.
*/
int sqlite3GetToken(const unsigned char *z, int *tokenType){
  int i, c;

    if( tokenType>=TK_WINDOW ){
      assert( tokenType==TK_SPACE || tokenType==TK_OVER || tokenType==TK_FILTER
           || tokenType==TK_ILLEGAL || tokenType==TK_WINDOW 
      );
#else
    if( tokenType>=TK_SPACE ){
      assert( tokenType==TK_SPACE || tokenType==TK_ILLEGAL );
#endif /* SQLITE_OMIT_WINDOWFUNC */
      if( db->u1.isInterrupted ){
        pParse->rc = SQLITE_INTERRUPT;
        break;
      }
      if( tokenType==TK_SPACE ){
        zSql += n;
        continue;

        tokenType = analyzeWindowKeyword((const u8*)&zSql[6]);
      }else if( tokenType==TK_OVER ){
        assert( n==4 );
        tokenType = analyzeOverKeyword((const u8*)&zSql[4], lastTokenParsed);
      }else if( tokenType==TK_FILTER ){
        assert( n==6 );
        tokenType = analyzeFilterKeyword((const u8*)&zSql[6], lastTokenParsed);
#endif /* SQLITE_OMIT_WINDOWFUNC */
      }else{
        sqlite3ErrorMsg(pParse, "unrecognized token: \"%.*s\"", n, zSql);
        break;
      }
    }
    pParse->sLastToken.z = zSql;
    pParse->sLastToken.n = n;

static void row_numberStepFunc(
  sqlite3_context *pCtx, 
  int nArg,
  sqlite3_value **apArg
){
  i64 *p = (i64*)sqlite3_aggregate_context(pCtx, sizeof(*p));
  if( p ) (*p)++;
  UNUSED_PARAMETER(nArg);
  UNUSED_PARAMETER(apArg);
}
static void row_numberValueFunc(sqlite3_context *pCtx){
  i64 *p = (i64*)sqlite3_aggregate_context(pCtx, sizeof(*p));
  sqlite3_result_int64(pCtx, (p ? *p : 0));
}

/*

  sqlite3_context *pCtx, 
  int nArg,
  sqlite3_value **apArg
){
  struct CallCount *p;
  p = (struct CallCount*)sqlite3_aggregate_context(pCtx, sizeof(*p));
  if( p ) p->nStep = 1;
  UNUSED_PARAMETER(nArg);
  UNUSED_PARAMETER(apArg);
}
static void dense_rankValueFunc(sqlite3_context *pCtx){
  struct CallCount *p;
  p = (struct CallCount*)sqlite3_aggregate_context(pCtx, sizeof(*p));
  if( p ){
    if( p->nStep ){
      p->nValue++;

  p = (struct CallCount*)sqlite3_aggregate_context(pCtx, sizeof(*p));
  if( p ){
    p->nStep++;
    if( p->nValue==0 ){
      p->nValue = p->nStep;
    }
  }
  UNUSED_PARAMETER(nArg);
  UNUSED_PARAMETER(apArg);
}
static void rankValueFunc(sqlite3_context *pCtx){
  struct CallCount *p;
  p = (struct CallCount*)sqlite3_aggregate_context(pCtx, sizeof(*p));
  if( p ){
    sqlite3_result_int64(pCtx, p->nValue);
    p->nValue = 0;

*/
static void percent_rankStepFunc(
  sqlite3_context *pCtx, 
  int nArg,
  sqlite3_value **apArg
){
  struct CallCount *p;
  UNUSED_PARAMETER(nArg); assert( nArg==1 );

  p = (struct CallCount*)sqlite3_aggregate_context(pCtx, sizeof(*p));
  if( p ){
    if( p->nTotal==0 ){
      p->nTotal = sqlite3_value_int64(apArg[0]);
    }
    p->nStep++;

*/
static void cume_distStepFunc(
  sqlite3_context *pCtx, 
  int nArg,
  sqlite3_value **apArg
){
  struct CallCount *p;
  assert( nArg==1 ); UNUSED_PARAMETER(nArg);

  p = (struct CallCount*)sqlite3_aggregate_context(pCtx, sizeof(*p));
  if( p ){
    if( p->nTotal==0 ){
      p->nTotal = sqlite3_value_int64(apArg[0]);
    }
    p->nStep++;

*/
static void ntileStepFunc(
  sqlite3_context *pCtx, 
  int nArg,
  sqlite3_value **apArg
){
  struct NtileCtx *p;
  assert( nArg==2 ); UNUSED_PARAMETER(nArg);
  p = (struct NtileCtx*)sqlite3_aggregate_context(pCtx, sizeof(*p));
  if( p ){
    if( p->nTotal==0 ){
      p->nParam = sqlite3_value_int64(apArg[0]);
      p->nTotal = sqlite3_value_int64(apArg[1]);
      if( p->nParam<=0 ){
        sqlite3_result_error(

*/
static void last_valueStepFunc(
  sqlite3_context *pCtx, 
  int nArg,
  sqlite3_value **apArg
){
  struct LastValueCtx *p;
  UNUSED_PARAMETER(nArg);
  p = (struct LastValueCtx*)sqlite3_aggregate_context(pCtx, sizeof(*p));
  if( p ){
    sqlite3_value_free(p->pVal);
    p->pVal = sqlite3_value_dup(apArg[0]);
    if( p->pVal==0 ){
      sqlite3_result_error_nomem(pCtx);
    }else{
      p->nVal++;
    }
  }
}
static void last_valueInvFunc(
  sqlite3_context *pCtx, 
  int nArg,
  sqlite3_value **apArg
){
  struct LastValueCtx *p;
  UNUSED_PARAMETER(nArg);
  UNUSED_PARAMETER(apArg);
  p = (struct LastValueCtx*)sqlite3_aggregate_context(pCtx, sizeof(*p));
  if( ALWAYS(p) ){
    p->nVal--;
    if( p->nVal==0 ){
      sqlite3_value_free(p->pVal);
      p->pVal = 0;
    }

** invoked.
*/
static void noopStepFunc(    /*NO_TEST*/
  sqlite3_context *p,        /*NO_TEST*/
  int n,                     /*NO_TEST*/
  sqlite3_value **a          /*NO_TEST*/
){                           /*NO_TEST*/
  UNUSED_PARAMETER(p);       /*NO_TEST*/
  UNUSED_PARAMETER(n);       /*NO_TEST*/
  UNUSED_PARAMETER(a);       /*NO_TEST*/
  assert(0);                 /*NO_TEST*/
}                            /*NO_TEST*/
static void noopValueFunc(sqlite3_context *p){ UNUSED_PARAMETER(p); /*no-op*/ }

/* Window functions that use all window interfaces: xStep, xFinal,
** xValue, and xInverse */
#define WINDOWFUNCALL(name,nArg,extra) {                                   \
  nArg, (SQLITE_UTF8|SQLITE_FUNC_WINDOW|extra), 0, 0,                      \
  name ## StepFunc, name ## FinalizeFunc, name ## ValueFunc,               \
  name ## InvFunc, name ## Name, {0}                                       \
}

/* Window functions that are implemented using bytecode and thus have
** no-op routines for their methods */
#define WINDOWFUNCNOOP(name,nArg,extra) {                                  \
  nArg, (SQLITE_UTF8|SQLITE_FUNC_WINDOW|extra), 0, 0,                      \
  noopStepFunc, noopValueFunc, noopValueFunc,                              \
  noopStepFunc, name ## Name, {0}                                          \
}

/* Window functions that use all window interfaces: xStep, the
** same routine for xFinalize and xValue and which never call
** xInverse. */
#define WINDOWFUNCX(name,nArg,extra) {                                     \
  nArg, (SQLITE_UTF8|SQLITE_FUNC_WINDOW|extra), 0, 0,                      \
  name ## StepFunc, name ## ValueFunc, name ## ValueFunc,                  \
  noopStepFunc, name ## Name, {0}                                          \
}


/*
** Register those built-in window functions that are not also aggregates.
*/
void sqlite3WindowFunctions(void){

    default: /* no-op */
      break;
  }

  return WRC_Continue;
}
static int selectWindowRewriteSelectCb(Walker *pWalker, Select *pSelect){
  UNUSED_PARAMETER(pWalker);
  UNUSED_PARAMETER(pSelect);
  return WRC_Prune;
}


/*
** Iterate through each expression in expression-list pEList. For each:
**

  int addr;
  int csrStart = pParse->nTab++;
  int csrEnd = pParse->nTab++;
  int regStart;                    /* Value of <expr> PRECEDING */
  int regEnd;                      /* Value of <expr> FOLLOWING */
  int addrGoto;
  int addrTop;
  int addrIfPos1 = 0;
  int addrIfPos2 = 0;
  int regSize = 0;

  assert( pMWin->eStart==TK_PRECEDING 
       || pMWin->eStart==TK_CURRENT 
       || pMWin->eStart==TK_FOLLOWING 
       || pMWin->eStart==TK_UNBOUNDED 
  );

  sqlite3VdbeAddOp2(v, OP_Integer, 0, regCtr);
  sqlite3VdbeAddOp2(v, OP_Rewind, csrLead, lblEmpty);
  VdbeCoverage(v);
  sqlite3VdbeAddOp2(v, OP_Rewind, pMWin->iEphCsr, lblEmpty);
  VdbeCoverageNeverTaken(v);

  if( bReverse ){
    int addr2 = sqlite3VdbeCurrentAddr(v);
    windowAggStep(pParse, pMWin, csrLead, 0, regArg, regSize);
    sqlite3VdbeAddOp2(v, OP_Next, csrLead, addr2);
    VdbeCoverage(v);
    sqlite3VdbeAddOp2(v, OP_Rewind, csrLead, lblEmpty);
    VdbeCoverageNeverTaken(v);
  }
  addrNext = sqlite3VdbeCurrentAddr(v);

  if( pOrderBy && (pMWin->eEnd==TK_CURRENT || pMWin->eStart==TK_CURRENT) ){

        if( 
#if YY_SHIFT_MIN+YYWILDCARD<0
          j>=0 &&
#endif
#if YY_SHIFT_MAX+YYWILDCARD>=YY_ACTTAB_COUNT
          j<YY_ACTTAB_COUNT &&
#endif
          j<(int)(sizeof(yy_lookahead)/sizeof(yy_lookahead[0])) &&
          yy_lookahead[j]==YYWILDCARD && iLookAhead>0
        ){
#ifndef NDEBUG
          if( yyTraceFILE ){
            fprintf(yyTraceFILE, "%sWILDCARD %s => %s\n",
               yyTracePrompt, yyTokenName[iLookAhead],
               yyTokenName[YYWILDCARD]);

/*
** Return the fallback token corresponding to canonical token iToken, or
** 0 if iToken has no fallback.
*/
int ParseFallback(int iToken){
#ifdef YYFALLBACK
  if( iToken<(int)(sizeof(yyFallback)/sizeof(yyFallback[0])) ){
    return yyFallback[iToken];
  }
#else
  (void)iToken;
#endif
  return 0;
}