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Overview
Comment:Completely remove the old SQL function system and replace it with the new user functions. The code currently compiles but it coredumps on the test suite. Do not use in its present state. (CVS 400)
Downloads: Tarball | ZIP archive | SQL archive
Timelines: family | ancestors | descendants | both | trunk
Files: files | file ages | folders
SHA1:50797fee5066ec9ea23b720e5ab7e8fc8ccc1988
User & Date: drh 2002-02-28 00:41:10
Context
2002-02-28
00:46
Added IFNULL and NVL functions. (CVS 401) check-in: c6a85c8e user: drh tags: trunk
00:41
Completely remove the old SQL function system and replace it with the new user functions. The code currently compiles but it coredumps on the test suite. Do not use in its present state. (CVS 400) check-in: 50797fee user: drh tags: trunk
2002-02-27
19:50
Try to reduce the number of malloc() for user-defined functions. Begin transfering built-in functions over to the user-define function mechanism. (CVS 399) check-in: c4f9e017 user: drh tags: trunk
Changes
Hide Diffs Unified Diffs Ignore Whitespace Patch

Changes to src/expr.c.

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**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains routines used for analyzing expressions and
** for generating VDBE code that evaluates expressions in SQLite.
**
** $Id: expr.c,v 1.48 2002/02/27 19:00:21 drh Exp $
*/
#include "sqliteInt.h"


/*
** Construct a new expression node and return a pointer to it.  Memory
** for this node is obtained from sqliteMalloc().  The calling function
................................................................................
        }
      }
    }
  }
  return 0;
}

#if 0 /* NOT USED */
/*
** Compare a token against a string.  Return TRUE if they match.
*/
static int sqliteTokenCmp(Token *pToken, const char *zStr){
  int n = strlen(zStr);
  if( n!=pToken->n ) return 0;
  return sqliteStrNICmp(pToken->z, zStr, n)==0;
}
#endif

/*
** Convert a function name into its integer identifier.  Return the
** identifier.  Return FN_Unknown if the function name is unknown.
*/
int sqliteFuncId(Token *pToken){
  static const struct {
     char *zName;
     int len;
     int id;
  } aFunc[] = {
     { "count",  5, FN_Count  },
     { "min",    3, FN_Min    },
     { "max",    3, FN_Max    },
     { "sum",    3, FN_Sum    },
     { "avg",    3, FN_Avg    },
     { "length", 6, FN_Length },
     { "substr", 6, FN_Substr },
     { "abs",    3, FN_Abs    },
     { "round",  5, FN_Round  },
  };
  int i;
  for(i=0; i<ArraySize(aFunc); i++){
    if( aFunc[i].len==pToken->n 
     && sqliteStrNICmp(pToken->z, aFunc[i].zName, aFunc[i].len)==0 ){
       return aFunc[i].id;
    }
  }
  return FN_Unknown;
}

/*
** Error check the functions in an expression.  Make sure all
** function names are recognized and all functions have the correct
** number of arguments.  Leave an error message in pParse->zErrMsg
** if anything is amiss.  Return the number of errors.
**
** if pIsAgg is not null and this expression is an aggregate function
................................................................................
** (like count(*) or max(value)) then write a 1 into *pIsAgg.
*/
int sqliteExprCheck(Parse *pParse, Expr *pExpr, int allowAgg, int *pIsAgg){
  int nErr = 0;
  if( pExpr==0 ) return 0;
  switch( pExpr->op ){
    case TK_FUNCTION: {
      int id = sqliteFuncId(&pExpr->token);
      int n = pExpr->pList ? pExpr->pList->nExpr : 0;
      int no_such_func = 0;
      int too_many_args = 0;
      int too_few_args = 0;
      int wrong_num_args = 0;
      int is_agg = 0;
      int i;
      pExpr->iColumn = id;
      switch( id ){
        case FN_Unknown: {
          UserFunc *pUser = sqliteFindUserFunction(pParse->db,


             pExpr->token.z, pExpr->token.n, n, 0);
          if( pUser==0 ){

            pUser = sqliteFindUserFunction(pParse->db,
               pExpr->token.z, pExpr->token.n, -1, 0);
            if( pUser==0 ){

              no_such_func = 1;
            }else{
              wrong_num_args = 1;
            }
          }else{
            is_agg = pUser->xFunc==0;
          }
          break;
        }
        case FN_Count: { 
          too_many_args = n>1;
          is_agg = 1;
          break;
        }
        case FN_Max:
        case FN_Min: {
          too_few_args = n<1;
          is_agg = n==1;
          break;
        }
        case FN_Avg:
        case FN_Sum: {
          too_many_args = n>1;
          too_few_args = n<1;
          is_agg = 1;
          break;
        }
        case FN_Abs:
        case FN_Length: {
          too_few_args = n<1;
          too_many_args = n>1;
          break;
        }
        case FN_Round: {
          too_few_args = n<1;
          too_many_args = n>2;
          break;
        }
        case FN_Substr: {
          too_few_args = n<3;
          too_many_args = n>3;
          break;
        }
        default: break;
      }
      if( is_agg && !allowAgg ){
        sqliteSetNString(&pParse->zErrMsg, "misuse of aggregate function ", -1,
           pExpr->token.z, pExpr->token.n, "()", 2, 0);
        pParse->nErr++;
        nErr++;
        is_agg = 0;
      }else if( no_such_func ){
        sqliteSetNString(&pParse->zErrMsg, "no such function: ", -1,
           pExpr->token.z, pExpr->token.n, 0);
        pParse->nErr++;
        nErr++;
      }else if( too_many_args ){
        sqliteSetNString(&pParse->zErrMsg, "too many arguments to function ",-1,
           pExpr->token.z, pExpr->token.n, "()", 2, 0);
        pParse->nErr++;
        nErr++;
      }else if( too_few_args ){
        sqliteSetNString(&pParse->zErrMsg, "too few arguments to function ",-1,
           pExpr->token.z, pExpr->token.n, "()", 2, 0);
        pParse->nErr++;
        nErr++;
      }else if( wrong_num_args ){
        sqliteSetNString(&pParse->zErrMsg, 
           "wrong number of arguments to function ",-1,
           pExpr->token.z, pExpr->token.n, "()", 2, 0);
        pParse->nErr++;
        nErr++;
      }
................................................................................
      dest = sqliteVdbeCurrentAddr(v) + 2;
      sqliteVdbeAddOp(v, op, 0, dest);
      sqliteVdbeAddOp(v, OP_AddImm, -1, 0);
      break;
    }
    case TK_AGG_FUNCTION: {
      sqliteVdbeAddOp(v, OP_AggGet, 0, pExpr->iAgg);
      if( pExpr->iColumn==FN_Avg ){
        assert( pParse->iAggCount>=0 && pParse->iAggCount<pParse->nAgg );
        sqliteVdbeAddOp(v, OP_AggGet, 0, pParse->iAggCount);
        sqliteVdbeAddOp(v, OP_Divide, 0, 0);
      }
      break;
    }
    case TK_FUNCTION: {
      int id = pExpr->iColumn;
      int op;
      int i;
      ExprList *pList = pExpr->pList;
      switch( id ){
        case FN_Min: 
        case FN_Max: {
          op = id==FN_Min ? OP_Min : OP_Max;
          for(i=0; i<pList->nExpr; i++){
            sqliteExprCode(pParse, pList->a[i].pExpr);
            if( i>0 ){
              sqliteVdbeAddOp(v, op, 0, 0);
            }
          }
          break;
        }
        case FN_Abs: {
          sqliteExprCode(pParse, pList->a[0].pExpr);
          sqliteVdbeAddOp(v, OP_AbsValue, 0, 0);
          break;
        }
        case FN_Round: {
          if( pList->nExpr==2 ){
            sqliteExprCode(pParse, pList->a[1].pExpr);
          }else{
            sqliteVdbeAddOp(v, OP_Integer, 0, 0);
          }
          sqliteExprCode(pParse, pList->a[0].pExpr);
          sqliteVdbeAddOp(v, OP_Precision, 0, 0);
          break;
        }
        case FN_Length: {
          sqliteExprCode(pParse, pList->a[0].pExpr);
          sqliteVdbeAddOp(v, OP_Strlen, 0, 0);
          break;
        }
        case FN_Substr: {
          for(i=0; i<pList->nExpr; i++){
            sqliteExprCode(pParse, pList->a[i].pExpr);
          }
          sqliteVdbeAddOp(v, OP_Substr, 0, 0);
          break;
        }
        case FN_Unknown: {
          UserFunc *pUser;

          pUser = sqliteFindUserFunction(pParse->db,
                      pExpr->token.z, pExpr->token.n, pList->nExpr, 0);
          assert( pUser!=0 );
          for(i=0; i<pList->nExpr; i++){
            sqliteExprCode(pParse, pList->a[i].pExpr);
          }
          sqliteVdbeAddOp(v, OP_UserFunc, pList->nExpr, 0);
          sqliteVdbeChangeP3(v, -1, (char*)pUser, P3_POINTER);
          break;
        }
        default: {
          /* Can't happen! */
          break;
        }
      }
      break;
    }
    case TK_SELECT: {
      sqliteVdbeAddOp(v, OP_MemLoad, pExpr->iColumn, 0);
      break;
    }
    case TK_IN: {
................................................................................
        pParse->aAgg[i].isAgg = 0;
        pParse->aAgg[i].pExpr = pExpr;
      }
      pExpr->iAgg = i;
      break;
    }
    case TK_AGG_FUNCTION: {
      if( pExpr->iColumn==FN_Count || pExpr->iColumn==FN_Avg ){
        if( pParse->iAggCount>=0 ){
          i = pParse->iAggCount;
        }else{
          i = appendAggInfo(pParse);
          if( i<0 ) return 1;
          pParse->aAgg[i].isAgg = 1;
          pParse->aAgg[i].pExpr = 0;
          pParse->iAggCount = i;
        }
        if( pExpr->iColumn==FN_Count ){
          pExpr->iAgg = i;
          break;
        }
      }
      aAgg = pParse->aAgg;
      for(i=0; i<pParse->nAgg; i++){
        if( !aAgg[i].isAgg ) continue;
        if( sqliteExprCompare(aAgg[i].pExpr, pExpr) ){
          break;
        }
      }
      if( i>=pParse->nAgg ){
        i = appendAggInfo(pParse);
        if( i<0 ) return 1;
        pParse->aAgg[i].isAgg = 1;
        pParse->aAgg[i].pExpr = pExpr;
        if( pExpr->iColumn==FN_Unknown ){
          pParse->aAgg[i].pUser = sqliteFindUserFunction(pParse->db,
             pExpr->token.z, pExpr->token.n, pExpr->pList->nExpr, 0);
        }else{
          pParse->aAgg[i].pUser = 0;
        }
      }
      pExpr->iAgg = i;
      break;
    }
    default: {
      if( pExpr->pLeft ){
        nErr = sqliteExprAnalyzeAggregates(pParse, pExpr->pLeft);
................................................................................
    }
  }
  return nErr;
}

/*
** Locate a user function given a name and a number of arguments.
** Return a pointer to the UserFunc structure that defines that
** function, or return NULL if the function does not exist.
**
** If the createFlag argument is true, then a new (blank) UserFunc
** structure is created and liked into the "db" structure if a
** no matching function previously existed.  When createFlag is true
** and the nArg parameter is -1, then only a function that accepts
** any number of arguments will be returned.
**
** If createFlag is false and nArg is -1, then the first valid
** function found is returned.  A function is valid if either xFunc
** or xStep is non-zero.
*/
UserFunc *sqliteFindUserFunction(
  sqlite *db,        /* An open database */
  const char *zName, /* Name of the function.  Not null-terminated */
  int nName,         /* Number of characters in the name */
  int nArg,          /* Number of arguments.  -1 means any number */
  int createFlag     /* Create new entry if true and does not otherwise exist */
){
  UserFunc *pFirst, *p, *pMaybe;
  pFirst = p = (UserFunc*)sqliteHashFind(&db->userFunc, zName, nName);
  if( p && !createFlag && nArg<0 ){
    while( p && p->xFunc==0 && p->xStep==0 ){ p = p->pNext; }
    return p;
  }
  pMaybe = 0;
  while( p && p->nArg!=nArg ){
    if( p->nArg<0 && !createFlag && (p->xFunc || p->xStep) ) pMaybe = p;
................................................................................
    assert( createFlag==0 );
    return pMaybe;
  }
  if( p==0 && createFlag ){
    p = sqliteMalloc( sizeof(*p) );
    p->nArg = nArg;
    p->pNext = pFirst;
    sqliteHashInsert(&db->userFunc, zName, nName, (void*)p);
  }
  return p;
}







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**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains routines used for analyzing expressions and
** for generating VDBE code that evaluates expressions in SQLite.
**
** $Id: expr.c,v 1.49 2002/02/28 00:41:10 drh Exp $
*/
#include "sqliteInt.h"


/*
** Construct a new expression node and return a pointer to it.  Memory
** for this node is obtained from sqliteMalloc().  The calling function
................................................................................
        }
      }
    }
  }
  return 0;
}










































/*
** Error check the functions in an expression.  Make sure all
** function names are recognized and all functions have the correct
** number of arguments.  Leave an error message in pParse->zErrMsg
** if anything is amiss.  Return the number of errors.
**
** if pIsAgg is not null and this expression is an aggregate function
................................................................................
** (like count(*) or max(value)) then write a 1 into *pIsAgg.
*/
int sqliteExprCheck(Parse *pParse, Expr *pExpr, int allowAgg, int *pIsAgg){
  int nErr = 0;
  if( pExpr==0 ) return 0;
  switch( pExpr->op ){
    case TK_FUNCTION: {

      int n = pExpr->pList ? pExpr->pList->nExpr : 0;
      int no_such_func = 0;


      int wrong_num_args = 0;
      int is_agg = 0;
      int i;




      FuncDef *pDef;

      pDef = sqliteFindFunction(pParse->db, pExpr->token.z, pExpr->token.n,n,0);

      if( pDef==0 ){
        pDef = sqliteFindFunction(pParse->db,
           pExpr->token.z, pExpr->token.n, -1, 0);

        if( pDef==0 ){
          no_such_func = 1;
        }else{
          wrong_num_args = 1;
        }
      }else{






        is_agg = pDef->xFunc==0;
































      }
      if( is_agg && !allowAgg ){
        sqliteSetNString(&pParse->zErrMsg, "misuse of aggregate function ", -1,
           pExpr->token.z, pExpr->token.n, "()", 2, 0);
        pParse->nErr++;
        nErr++;
        is_agg = 0;
      }else if( no_such_func ){
        sqliteSetNString(&pParse->zErrMsg, "no such function: ", -1,
           pExpr->token.z, pExpr->token.n, 0);
        pParse->nErr++;
        nErr++;










      }else if( wrong_num_args ){
        sqliteSetNString(&pParse->zErrMsg, 
           "wrong number of arguments to function ",-1,
           pExpr->token.z, pExpr->token.n, "()", 2, 0);
        pParse->nErr++;
        nErr++;
      }
................................................................................
      dest = sqliteVdbeCurrentAddr(v) + 2;
      sqliteVdbeAddOp(v, op, 0, dest);
      sqliteVdbeAddOp(v, OP_AddImm, -1, 0);
      break;
    }
    case TK_AGG_FUNCTION: {
      sqliteVdbeAddOp(v, OP_AggGet, 0, pExpr->iAgg);





      break;
    }
    case TK_FUNCTION: {


      int i;
      ExprList *pList = pExpr->pList;









































      FuncDef *pDef;
      pDef = sqliteFindFunction(pParse->db,
                      pExpr->token.z, pExpr->token.n, pList->nExpr, 0);
      assert( pDef!=0 );
      for(i=0; i<pList->nExpr; i++){
        sqliteExprCode(pParse, pList->a[i].pExpr);
      }
      sqliteVdbeAddOp(v, OP_Function, pList->nExpr, 0);
      sqliteVdbeChangeP3(v, -1, (char*)pDef, P3_POINTER);







      break;
    }
    case TK_SELECT: {
      sqliteVdbeAddOp(v, OP_MemLoad, pExpr->iColumn, 0);
      break;
    }
    case TK_IN: {
................................................................................
        pParse->aAgg[i].isAgg = 0;
        pParse->aAgg[i].pExpr = pExpr;
      }
      pExpr->iAgg = i;
      break;
    }
    case TK_AGG_FUNCTION: {















      aAgg = pParse->aAgg;
      for(i=0; i<pParse->nAgg; i++){
        if( !aAgg[i].isAgg ) continue;
        if( sqliteExprCompare(aAgg[i].pExpr, pExpr) ){
          break;
        }
      }
      if( i>=pParse->nAgg ){
        i = appendAggInfo(pParse);
        if( i<0 ) return 1;
        pParse->aAgg[i].isAgg = 1;
        pParse->aAgg[i].pExpr = pExpr;
        pParse->aAgg[i].pFunc = sqliteFindFunction(pParse->db,

             pExpr->token.z, pExpr->token.n, pExpr->pList->nExpr, 0);



      }
      pExpr->iAgg = i;
      break;
    }
    default: {
      if( pExpr->pLeft ){
        nErr = sqliteExprAnalyzeAggregates(pParse, pExpr->pLeft);
................................................................................
    }
  }
  return nErr;
}

/*
** Locate a user function given a name and a number of arguments.
** Return a pointer to the FuncDef structure that defines that
** function, or return NULL if the function does not exist.
**
** If the createFlag argument is true, then a new (blank) FuncDef
** structure is created and liked into the "db" structure if a
** no matching function previously existed.  When createFlag is true
** and the nArg parameter is -1, then only a function that accepts
** any number of arguments will be returned.
**
** If createFlag is false and nArg is -1, then the first valid
** function found is returned.  A function is valid if either xFunc
** or xStep is non-zero.
*/
FuncDef *sqliteFindFunction(
  sqlite *db,        /* An open database */
  const char *zName, /* Name of the function.  Not null-terminated */
  int nName,         /* Number of characters in the name */
  int nArg,          /* Number of arguments.  -1 means any number */
  int createFlag     /* Create new entry if true and does not otherwise exist */
){
  FuncDef *pFirst, *p, *pMaybe;
  pFirst = p = (FuncDef*)sqliteHashFind(&db->aFunc, zName, nName);
  if( p && !createFlag && nArg<0 ){
    while( p && p->xFunc==0 && p->xStep==0 ){ p = p->pNext; }
    return p;
  }
  pMaybe = 0;
  while( p && p->nArg!=nArg ){
    if( p->nArg<0 && !createFlag && (p->xFunc || p->xStep) ) pMaybe = p;
................................................................................
    assert( createFlag==0 );
    return pMaybe;
  }
  if( p==0 && createFlag ){
    p = sqliteMalloc( sizeof(*p) );
    p->nArg = nArg;
    p->pNext = pFirst;
    sqliteHashInsert(&db->aFunc, zName, nName, (void*)p);
  }
  return p;
}

Changes to src/func.c.

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** This file contains the C functions that implement various SQL
** functions of SQLite.  
**
** There is only one exported symbol in this file - the function
** sqliteRegisterBuildinFunctions() found at the bottom of the file.
** All other code has file scope.
**
** $Id: func.c,v 1.5 2002/02/27 19:50:59 drh Exp $
*/
#include <ctype.h>
#include <math.h>
#include <stdlib.h>

#include "sqlite.h"






















































































































/*
** Implementation of the upper() and lower() SQL functions.
*/
static void upperFunc(sqlite_func *context, int argc, const char **argv){
  char *z;
  int i;
................................................................................
  StdDevCtx *p = sqlite_aggregate_context(context, sizeof(*p));
  if( p && rN>1.0 ){
    sqlite_set_result_double(context, 
       sqrt((p->sum2 - p->sum*p->sum/rN)/(rN-1.0)));
  }
}




























/*




































































** This function registered all of the above C functions as SQL
** functions.  This should be the only routine in this file with
** external linkage.
*/
void sqliteRegisterBuildinFunctions(sqlite *db){
































  sqlite_create_function(db, "upper", 1, upperFunc, 0);
  sqlite_create_function(db, "lower", 1, lowerFunc, 0);
  sqlite_create_aggregate(db, "stddev", 1, stdDevStep, stdDevFinalize, 0);



  sqlite_create_aggregate(db, "x_sum", 1, sumStep, sumFinalize, 0);
  sqlite_create_aggregate(db, "x_avg", 1, sumStep, avgFinalize, 0);

}








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** This file contains the C functions that implement various SQL
** functions of SQLite.  
**
** There is only one exported symbol in this file - the function
** sqliteRegisterBuildinFunctions() found at the bottom of the file.
** All other code has file scope.
**
** $Id: func.c,v 1.6 2002/02/28 00:41:10 drh Exp $
*/
#include <ctype.h>
#include <math.h>
#include <stdlib.h>
#include <assert.h>
#include "sqliteInt.h"

/*
** Implementation of the non-aggregate min() and max() functions
*/
static void minFunc(sqlite_func *context, int argc, const char **argv){
  const char *zBest; 
  int i;

  zBest = argv[0];
  for(i=1; i<argc; i++){
    if( sqliteCompare(argv[i], zBest)<0 ){
      zBest = argv[i];
    }
  }
  sqlite_set_result_string(context, zBest, -1);
}
static void maxFunc(sqlite_func *context, int argc, const char **argv){
  const char *zBest; 
  int i;

  zBest = argv[0];
  for(i=1; i<argc; i++){
    if( sqliteCompare(argv[i], zBest)>0 ){
      zBest = argv[i];
    }
  }
  sqlite_set_result_string(context, zBest, -1);
}

/*
** Implementation of the length() function
*/
static void lengthFunc(sqlite_func *context, int argc, const char **argv){
  const char *z;
  int len;

  assert( argc==1 );
  z = argv[0];
  if( z==0 ){
    len = 0;
  }else{
#ifdef SQLITE_UTF8
    for(len=0; *z; z++){ if( (0xc0&*z)!=0x80 ) len++; }
#else
    len = strlen(z);
#endif
  }
  sqlite_set_result_int(context, len);
}

/*
** Implementation of the abs() function
*/
static void absFunc(sqlite_func *context, int argc, const char **argv){
  const char *z;
  assert( argc==1 );
  z = argv[0];
  if( z && z[0]=='-' && isdigit(z[1]) ) z++;
  sqlite_set_result_string(context, z, -1);
}

/*
** Implementation of the substr() function
*/
static void substrFunc(sqlite_func *context, int argc, const char **argv){
  const char *z;
#ifdef SQLITE_UTF8
  const char *z2;
  int i;
#endif
  int p1, p2, len;
  assert( argc==3 );
  z = argv[0];
  if( z==0 ) return;
  p1 = atoi(argv[1]?argv[1]:0);
  p2 = atoi(argv[2]?argv[2]:0);
#ifdef SQLITE_UTF8
  for(len=0, z2=z; *z2; z2++){ if( (0xc0&*z)!=0x80 ) len++; }
#else
  len = strlen(z);
#endif
  if( p1<0 ){
    p1 = len-p1;
  }else if( p1>0 ){
    p1--;
  }
  if( p1+p2>len ){
    p2 = len-p1;
  }
#ifdef SQLITE_UTF8
  for(i=0; i<p1; i++){
    assert( z[i] );
    if( (z[i]&0xc0)!=0x80 ) p1++;
  }
  for(; i<p1+p2; i++){
    assert( z[i] );
    if( (z[i]&0xc0)!=0x80 ) p2++;
  }
#endif
  sqlite_set_result_string(context, &z[p1], p2);
}

/*
** Implementation of the round() function
*/
static void roundFunc(sqlite_func *context, int argc, const char **argv){
  int n;
  double r;
  char zBuf[100];
  assert( argc==1 || argc==2 );
  n = argc==2 && argv[1] ? atoi(argv[1]) : 0;
  if( n>30 ) n = 30;
  if( n<0 ) n = 0;
  r = argv[0] ? atof(argv[0]) : 0.0;
  sprintf(zBuf,"%.*f",n,r);
  sqlite_set_result_string(context, zBuf, -1);
}

/*
** Implementation of the upper() and lower() SQL functions.
*/
static void upperFunc(sqlite_func *context, int argc, const char **argv){
  char *z;
  int i;
................................................................................
  StdDevCtx *p = sqlite_aggregate_context(context, sizeof(*p));
  if( p && rN>1.0 ){
    sqlite_set_result_double(context, 
       sqrt((p->sum2 - p->sum*p->sum/rN)/(rN-1.0)));
  }
}

/*
** The following structure keeps track of state information for the
** count() aggregate function.
*/
typedef struct CountCtx CountCtx;
struct CountCtx {
  int n;
};

/*
** Routines to implement the count() aggregate function.
*/
static void countStep(sqlite_func *context, int argc, const char **argv){
  CountCtx *p;
  p = sqlite_aggregate_context(context, sizeof(*p));
  if( (argc==0 || argv[0]) && p ){
    p->n++;
  }
}   
static void countFinalize(sqlite_func *context){
  CountCtx *p;
  p = sqlite_aggregate_context(context, sizeof(*p));
  if( p ){
    sqlite_set_result_int(context, p->n);
  }
}

/*
** This function tracks state information for the min() and max()
** aggregate functions.
*/
typedef struct MinMaxCtx MinMaxCtx;
struct MinMaxCtx {
  char *z;         /* The best so far */
  char zBuf[28];   /* Space that can be used for storage */
};

/*
** Routines to implement min() and max() aggregate functions.
*/
static void minStep(sqlite_func *context, int argc, const char **argv){
  MinMaxCtx *p;
  p = sqlite_aggregate_context(context, sizeof(*p));
  if( p==0 || argc<1 ) return;
  if( sqlite_aggregate_count(context)==1 || sqliteCompare(argv[0],p->z)<0 ){
    if( p->z && p->z!=p->zBuf ){
      sqliteFree(p->z);
    }
    if( argv[0] ){
      int len = strlen(argv[0]);
      if( len < sizeof(p->zBuf) ){
        p->z = p->zBuf;
      }else{
        p->z = sqliteMalloc( len+1 );
        if( p->z==0 ) return;
      }
      strcpy(p->z, argv[0]);
    }else{
      p->z = 0;
    }
  }
}
static void maxStep(sqlite_func *context, int argc, const char **argv){
  MinMaxCtx *p;
  p = sqlite_aggregate_context(context, sizeof(*p));
  if( p==0 || argc<1 ) return;
  if( sqlite_aggregate_count(context)==1 || sqliteCompare(argv[0],p->z)>0 ){
    if( p->z && p->z!=p->zBuf ){
      sqliteFree(p->z);
    }
    if( argv[0] ){
      int len = strlen(argv[0]);
      if( len < sizeof(p->zBuf) ){
        p->z = p->zBuf;
      }else{
        p->z = sqliteMalloc( len+1 );
        if( p->z==0 ) return;
      }
      strcpy(p->z, argv[0]);
    }else{
      p->z = 0;
    }
  }
}
static void minMaxFinalize(sqlite_func *context){
  MinMaxCtx *p;
  p = sqlite_aggregate_context(context, sizeof(*p));
  if( p && p->z ){
    sqlite_set_result_string(context, p->z, strlen(p->z));
  }
  if( p && p->z && p->z!=p->zBuf ){
    sqliteFree(p->z);
  }
}

/*
** This function registered all of the above C functions as SQL
** functions.  This should be the only routine in this file with
** external linkage.
*/
void sqliteRegisterBuildinFunctions(sqlite *db){
  static struct {
     char *zName;
     int nArg;
     void (*xFunc)(sqlite_func*,int,const char**);
  } aFuncs[] = {
    { "min",  -1,  minFunc    },
    { "max",  -1,  maxFunc    },
    { "length", 1, lengthFunc },
    { "substr", 3, substrFunc },
    { "abs",    1, absFunc    },
    { "round",  1, roundFunc  },
    { "round",  2, roundFunc  },
    { "upper",  1, upperFunc  },
    { "lower",  1, lowerFunc  },
  };
  static struct {
    char *zName;
    int nArg;
    void (*xStep)(sqlite_func*,int,const char**);
    void (*xFinalize)(sqlite_func*);
  } aAggs[] = {
    { "min",    1, minStep,      minMaxFinalize },
    { "max",    1, maxStep,      minMaxFinalize },
    { "sum",    1, sumStep,      sumFinalize    },
    { "avg",    1, sumStep,      avgFinalize    },
    { "count",  0, countStep,    countFinalize  },
    { "count",  1, countStep,    countFinalize  },
    { "stddev", 1, stdDevStep,   stdDevFinalize },
  };
  int i;

  for(i=0; i<sizeof(aFuncs)/sizeof(aFuncs[0]); i++){
    sqlite_create_function(db, aFuncs[i].zName,


           aFuncs[i].nArg, aFuncs[i].xFunc, 0);
  }
  for(i=0; i<sizeof(aAggs)/sizeof(aAggs[0]); i++){
    sqlite_create_aggregate(db, aAggs[i].zName,

           aAggs[i].nArg, aAggs[i].xStep, aAggs[i].xFinalize, 0);
  }
}

Changes to src/main.c.

10
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**
*************************************************************************
** Main file for the SQLite library.  The routines in this file
** implement the programmer interface to the library.  Routines in
** other files are for internal use by SQLite and should not be
** accessed by users of the library.
**
** $Id: main.c,v 1.65 2002/02/27 19:00:22 drh Exp $
*/
#include "sqliteInt.h"
#include "os.h"

/*
** This is the callback routine for the code that initializes the
** database.  See sqliteInit() below for additional information.
................................................................................
  db = sqliteMalloc( sizeof(sqlite) );
  if( pzErrMsg ) *pzErrMsg = 0;
  if( db==0 ) goto no_mem_on_open;
  sqliteHashInit(&db->tblHash, SQLITE_HASH_STRING, 0);
  sqliteHashInit(&db->idxHash, SQLITE_HASH_STRING, 0);
  sqliteHashInit(&db->tblDrop, SQLITE_HASH_POINTER, 0);
  sqliteHashInit(&db->idxDrop, SQLITE_HASH_POINTER, 0);
  sqliteHashInit(&db->userFunc, SQLITE_HASH_STRING, 1);
  sqliteRegisterBuildinFunctions(db);
  db->onError = OE_Default;
  db->priorNewRowid = 0;
  
  /* Open the backend database driver */
  rc = sqliteBtreeOpen(zFilename, mode, MAX_PAGES, &db->pBe);
  if( rc!=SQLITE_OK ){
................................................................................
void sqlite_close(sqlite *db){
  HashElem *i;
  sqliteBtreeClose(db->pBe);
  clearHashTable(db, 0);
  if( db->pBeTemp ){
    sqliteBtreeClose(db->pBeTemp);
  }
  for(i=sqliteHashFirst(&db->userFunc); i; i=sqliteHashNext(i)){
    UserFunc *pFunc, *pNext;
    for(pFunc = (UserFunc*)sqliteHashData(i); pFunc; pFunc=pNext){
      pNext = pFunc->pNext;
      sqliteFree(pFunc);
    }
  }
  sqliteHashClear(&db->userFunc);
  sqliteFree(db);
}

/*
** Return TRUE if the given SQL string ends in a semicolon.
*/
int sqlite_complete(const char *zSql){
................................................................................
int sqlite_create_function(
  sqlite *db,          /* Add the function to this database connection */
  const char *zName,   /* Name of the function to add */
  int nArg,            /* Number of arguments */
  void (*xFunc)(sqlite_func*,int,const char**),  /* The implementation */
  void *pUserData      /* User data */
){
  UserFunc *p;
  if( db==0 || zName==0 ) return 1;
  p = sqliteFindUserFunction(db, zName, strlen(zName), nArg, 1);
  if( p==0 ) return 1;
  p->xFunc = xFunc;
  p->xStep = 0;
  p->xFinalize = 0;
  p->pUserData = pUserData;
  return 0;
}
................................................................................
  sqlite *db,          /* Add the function to this database connection */
  const char *zName,   /* Name of the function to add */
  int nArg,            /* Number of arguments */
  void (*xStep)(sqlite_func*,int,const char**), /* The step function */
  void (*xFinalize)(sqlite_func*),              /* The finalizer */
  void *pUserData      /* User data */
){
  UserFunc *p;
  if( db==0 || zName==0 ) return 1;
  p = sqliteFindUserFunction(db, zName, strlen(zName), nArg, 1);
  if( p==0 ) return 1;
  p->xFunc = 0;
  p->xStep = xStep;
  p->xFinalize = xFinalize;
  p->pUserData = pUserData;
  return 0;
}







|







 







|







 







|
|
|




|







 







|

|







 







|

|







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**
*************************************************************************
** Main file for the SQLite library.  The routines in this file
** implement the programmer interface to the library.  Routines in
** other files are for internal use by SQLite and should not be
** accessed by users of the library.
**
** $Id: main.c,v 1.66 2002/02/28 00:41:11 drh Exp $
*/
#include "sqliteInt.h"
#include "os.h"

/*
** This is the callback routine for the code that initializes the
** database.  See sqliteInit() below for additional information.
................................................................................
  db = sqliteMalloc( sizeof(sqlite) );
  if( pzErrMsg ) *pzErrMsg = 0;
  if( db==0 ) goto no_mem_on_open;
  sqliteHashInit(&db->tblHash, SQLITE_HASH_STRING, 0);
  sqliteHashInit(&db->idxHash, SQLITE_HASH_STRING, 0);
  sqliteHashInit(&db->tblDrop, SQLITE_HASH_POINTER, 0);
  sqliteHashInit(&db->idxDrop, SQLITE_HASH_POINTER, 0);
  sqliteHashInit(&db->aFunc, SQLITE_HASH_STRING, 1);
  sqliteRegisterBuildinFunctions(db);
  db->onError = OE_Default;
  db->priorNewRowid = 0;
  
  /* Open the backend database driver */
  rc = sqliteBtreeOpen(zFilename, mode, MAX_PAGES, &db->pBe);
  if( rc!=SQLITE_OK ){
................................................................................
void sqlite_close(sqlite *db){
  HashElem *i;
  sqliteBtreeClose(db->pBe);
  clearHashTable(db, 0);
  if( db->pBeTemp ){
    sqliteBtreeClose(db->pBeTemp);
  }
  for(i=sqliteHashFirst(&db->aFunc); i; i=sqliteHashNext(i)){
    FuncDef *pFunc, *pNext;
    for(pFunc = (FuncDef*)sqliteHashData(i); pFunc; pFunc=pNext){
      pNext = pFunc->pNext;
      sqliteFree(pFunc);
    }
  }
  sqliteHashClear(&db->aFunc);
  sqliteFree(db);
}

/*
** Return TRUE if the given SQL string ends in a semicolon.
*/
int sqlite_complete(const char *zSql){
................................................................................
int sqlite_create_function(
  sqlite *db,          /* Add the function to this database connection */
  const char *zName,   /* Name of the function to add */
  int nArg,            /* Number of arguments */
  void (*xFunc)(sqlite_func*,int,const char**),  /* The implementation */
  void *pUserData      /* User data */
){
  FuncDef *p;
  if( db==0 || zName==0 ) return 1;
  p = sqliteFindFunction(db, zName, strlen(zName), nArg, 1);
  if( p==0 ) return 1;
  p->xFunc = xFunc;
  p->xStep = 0;
  p->xFinalize = 0;
  p->pUserData = pUserData;
  return 0;
}
................................................................................
  sqlite *db,          /* Add the function to this database connection */
  const char *zName,   /* Name of the function to add */
  int nArg,            /* Number of arguments */
  void (*xStep)(sqlite_func*,int,const char**), /* The step function */
  void (*xFinalize)(sqlite_func*),              /* The finalizer */
  void *pUserData      /* User data */
){
  FuncDef *p;
  if( db==0 || zName==0 ) return 1;
  p = sqliteFindFunction(db, zName, strlen(zName), nArg, 1);
  if( p==0 ) return 1;
  p->xFunc = 0;
  p->xStep = xStep;
  p->xFinalize = xFinalize;
  p->pUserData = pUserData;
  return 0;
}

Changes to src/select.c.

8
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852
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856
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858
....
1147
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....
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1199
1200
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....
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1296
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1300
1301
1302
1303
1304
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1306
1307
**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains C code routines that are called by the parser
** to handle SELECT statements in SQLite.
**
** $Id: select.c,v 1.68 2002/02/27 19:00:22 drh Exp $
*/
#include "sqliteInt.h"

/*
** Allocate a new Select structure and return a pointer to that
** structure.
*/
................................................................................
/*
** Delete the aggregate information from the parse structure.
*/
static void sqliteAggregateInfoReset(Parse *pParse){
  sqliteFree(pParse->aAgg);
  pParse->aAgg = 0;
  pParse->nAgg = 0;
  pParse->iAggCount = -1;
  pParse->useAgg = 0;
}

/*
** This routine generates the code for the inside of the inner loop
** of a SELECT.
**
................................................................................
  */
  if( p->pGroupBy || p->pHaving || p->pWhere ) return 0;
  if( p->pSrc->nId!=1 ) return 0;
  if( p->pEList->nExpr!=1 ) return 0;
  pExpr = p->pEList->a[0].pExpr;
  if( pExpr->op!=TK_AGG_FUNCTION ) return 0;
  if( pExpr->pList==0 || pExpr->pList->nExpr!=1 ) return 0;
  if( pExpr->iColumn!=FN_Min && pExpr->iColumn!=FN_Max ) return 0;
  seekOp = pExpr->iColumn==FN_Min ? OP_Rewind : OP_Last;






  pExpr = pExpr->pList->a[0].pExpr;
  if( pExpr->op!=TK_COLUMN ) return 0;
  iCol = pExpr->iColumn;
  pTab = p->pSrc->a[0].pTab;

  /* If we get to here, it means the query is of the correct form.
  ** Check to make sure we have an index and make pIdx point to the
................................................................................
    pParse->nTab = oldNTab;
  }

  /* Do an analysis of aggregate expressions.
  */
  sqliteAggregateInfoReset(pParse);
  if( isAgg ){
    assert( pParse->nAgg==0 && pParse->iAggCount<0 );
    for(i=0; i<pEList->nExpr; i++){
      if( sqliteExprAnalyzeAggregates(pParse, pEList->a[i].pExpr) ){
        goto select_end;
      }
    }
    if( pGroupBy ){
      for(i=0; i<pGroupBy->nExpr; i++){
................................................................................
  }

  /* Reset the aggregator
  */
  if( isAgg ){
    sqliteVdbeAddOp(v, OP_AggReset, 0, pParse->nAgg);
    for(i=0; i<pParse->nAgg; i++){
      UserFunc *pUser;
      if( (pUser = pParse->aAgg[i].pUser)!=0 && pUser->xFinalize!=0 ){
        sqliteVdbeAddOp(v, OP_AggInit, 0, i);
        sqliteVdbeChangeP3(v, -1, (char*)pUser, P3_POINTER);
      }
    }
    if( pGroupBy==0 ){
      sqliteVdbeAddOp(v, OP_String, 0, 0);
      sqliteVdbeAddOp(v, OP_AggFocus, 0, 0);
      for(i=0; i<pParse->nAgg; i++){
        Expr *pE;
        if( !pParse->aAgg[i].isAgg ) continue;
        pE = pParse->aAgg[i].pExpr;
        assert( pE==0 || pE->op==TK_AGG_FUNCTION );
        assert( pE==0 || (pE->pList!=0 && pE->pList->nExpr==1) );
        if( pE==0 || pE->iColumn==FN_Sum ){
          sqliteVdbeAddOp(v, OP_Integer, 0, 0);
          sqliteVdbeAddOp(v, OP_AggSet, 0, i);
          continue;
        }
      }
    }
  }

  /* Initialize the memory cell to NULL
  */
  if( eDest==SRT_Mem ){
    sqliteVdbeAddOp(v, OP_String, 0, 0);
................................................................................
        sqliteExprCode(pParse, pParse->aAgg[i].pExpr);
        sqliteVdbeAddOp(v, OP_AggSet, 0, i);
      }
      sqliteVdbeResolveLabel(v, lbl1);
    }
    for(i=0; i<pParse->nAgg; i++){
      Expr *pE;
      int op, j;
      if( !pParse->aAgg[i].isAgg ) continue;
      pE = pParse->aAgg[i].pExpr;
      if( pE==0 ){
        sqliteVdbeAddOp(v, OP_AggIncr, 1, i);
        continue;
      }
      assert( pE->op==TK_AGG_FUNCTION );
      assert( pE->pList!=0 );
      for(j=0; j<pE->pList->nExpr; j++){
        sqliteExprCode(pParse, pE->pList->a[j].pExpr);
      }
      switch( pE->iColumn ){
        case FN_Min:      op = OP_Min;     break;
        case FN_Max:      op = OP_Max;     break;
        case FN_Avg:      op = OP_Add;     break;
        case FN_Sum:      op = OP_Add;     break;
        case FN_Unknown:  op = OP_AggFunc; break;
      }
      if( op!=OP_AggFunc ){
        sqliteVdbeAddOp(v, OP_AggGet, 0, i);
        sqliteVdbeAddOp(v, op, 0, 0);
        sqliteVdbeAddOp(v, OP_AggSet, 0, i);
      }else{
        sqliteVdbeAddOp(v, OP_Integer, i, 0);
        sqliteVdbeAddOp(v, OP_AggFunc, 0, pE->pList->nExpr);
        assert( pParse->aAgg[i].pUser!=0 );
        assert( pParse->aAgg[i].pUser->xStep!=0 );
        sqliteVdbeChangeP3(v, -1, (char*)pParse->aAgg[i].pUser, P3_POINTER);
      }
    }
  }

  /* End the database scan loop.
  */
  sqliteWhereEnd(pWInfo);








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1272





1273
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1277

1278
1279
1280
1281
1282
1283
1284
**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains C code routines that are called by the parser
** to handle SELECT statements in SQLite.
**
** $Id: select.c,v 1.69 2002/02/28 00:41:11 drh Exp $
*/
#include "sqliteInt.h"

/*
** Allocate a new Select structure and return a pointer to that
** structure.
*/
................................................................................
/*
** Delete the aggregate information from the parse structure.
*/
static void sqliteAggregateInfoReset(Parse *pParse){
  sqliteFree(pParse->aAgg);
  pParse->aAgg = 0;
  pParse->nAgg = 0;

  pParse->useAgg = 0;
}

/*
** This routine generates the code for the inside of the inner loop
** of a SELECT.
**
................................................................................
  */
  if( p->pGroupBy || p->pHaving || p->pWhere ) return 0;
  if( p->pSrc->nId!=1 ) return 0;
  if( p->pEList->nExpr!=1 ) return 0;
  pExpr = p->pEList->a[0].pExpr;
  if( pExpr->op!=TK_AGG_FUNCTION ) return 0;
  if( pExpr->pList==0 || pExpr->pList->nExpr!=1 ) return 0;
  if( pExpr->token.n!=3 ) return 0;
  if( sqliteStrNICmp(pExpr->token.z,"min",3)==0 ){
    seekOp = OP_Rewind;
  }else if( sqliteStrNICmp(pExpr->token.z,"max",3)==0 ){
    seekOp = OP_Last;
  }else{
    return 0;
  }
  pExpr = pExpr->pList->a[0].pExpr;
  if( pExpr->op!=TK_COLUMN ) return 0;
  iCol = pExpr->iColumn;
  pTab = p->pSrc->a[0].pTab;

  /* If we get to here, it means the query is of the correct form.
  ** Check to make sure we have an index and make pIdx point to the
................................................................................
    pParse->nTab = oldNTab;
  }

  /* Do an analysis of aggregate expressions.
  */
  sqliteAggregateInfoReset(pParse);
  if( isAgg ){
    assert( pParse->nAgg==0 );
    for(i=0; i<pEList->nExpr; i++){
      if( sqliteExprAnalyzeAggregates(pParse, pEList->a[i].pExpr) ){
        goto select_end;
      }
    }
    if( pGroupBy ){
      for(i=0; i<pGroupBy->nExpr; i++){
................................................................................
  }

  /* Reset the aggregator
  */
  if( isAgg ){
    sqliteVdbeAddOp(v, OP_AggReset, 0, pParse->nAgg);
    for(i=0; i<pParse->nAgg; i++){
      FuncDef *pFunc;
      if( (pFunc = pParse->aAgg[i].pFunc)!=0 && pFunc->xFinalize!=0 ){
        sqliteVdbeAddOp(v, OP_AggInit, 0, i);
        sqliteVdbeChangeP3(v, -1, (char*)pFunc, P3_POINTER);
      }
    }
    if( pGroupBy==0 ){
      sqliteVdbeAddOp(v, OP_String, 0, 0);
      sqliteVdbeAddOp(v, OP_AggFocus, 0, 0);












    }
  }

  /* Initialize the memory cell to NULL
  */
  if( eDest==SRT_Mem ){
    sqliteVdbeAddOp(v, OP_String, 0, 0);
................................................................................
        sqliteExprCode(pParse, pParse->aAgg[i].pExpr);
        sqliteVdbeAddOp(v, OP_AggSet, 0, i);
      }
      sqliteVdbeResolveLabel(v, lbl1);
    }
    for(i=0; i<pParse->nAgg; i++){
      Expr *pE;
      int j;
      if( !pParse->aAgg[i].isAgg ) continue;
      pE = pParse->aAgg[i].pExpr;




      assert( pE->op==TK_AGG_FUNCTION );
      if( pE->pList ){
        for(j=0; j<pE->pList->nExpr; j++){
          sqliteExprCode(pParse, pE->pList->a[j].pExpr);
        }






      }





      sqliteVdbeAddOp(v, OP_Integer, i, 0);
      sqliteVdbeAddOp(v, OP_AggFunc, 0, pE->pList->nExpr);
      assert( pParse->aAgg[i].pFunc!=0 );
      assert( pParse->aAgg[i].pFunc->xStep!=0 );
      sqliteVdbeChangeP3(v, -1, (char*)pParse->aAgg[i].pFunc, P3_POINTER);

    }
  }

  /* End the database scan loop.
  */
  sqliteWhereEnd(pWInfo);

Changes to src/sqliteInt.h.

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8
9
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...
648
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656
**    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.
**
*************************************************************************
** Internal interface definitions for SQLite.
**
** @(#) $Id: sqliteInt.h,v 1.95 2002/02/27 19:00:22 drh Exp $
*/
#include "sqlite.h"
#include "hash.h"
#include "vdbe.h"
#include "parse.h"
#include "btree.h"
#include <stdio.h>
................................................................................

/*
** A convenience macro that returns the number of elements in
** an array.
*/
#define ArraySize(X)    (sizeof(X)/sizeof(X[0]))

/*
** Integer identifiers for built-in SQL functions.
*/
#define FN_Unknown    0      /* Not a built-in.  Might be user defined */
#define FN_Count      1
#define FN_Min        2
#define FN_Max        3
#define FN_Sum        4
#define FN_Avg        5
#define FN_Fcnt       6
#define FN_Length     7
#define FN_Substr     8
#define FN_Abs        9
#define FN_Round      10

/*
** Forward references to structures
*/
typedef struct Column Column;
typedef struct Table Table;
typedef struct Index Index;
typedef struct Instruction Instruction;
................................................................................
typedef struct Parse Parse;
typedef struct Token Token;
typedef struct IdList IdList;
typedef struct WhereInfo WhereInfo;
typedef struct WhereLevel WhereLevel;
typedef struct Select Select;
typedef struct AggExpr AggExpr;
typedef struct UserFunc UserFunc;

/*
** Each database is an instance of the following structure
*/
struct sqlite {
  Btree *pBe;                   /* The B*Tree backend */
  Btree *pBeTemp;               /* Backend for session temporary tables */
................................................................................
  int nTable;                   /* Number of tables in the database */
  void *pBusyArg;               /* 1st Argument to the busy callback */
  int (*xBusyCallback)(void *,const char*,int);  /* The busy callback */
  Hash tblHash;                 /* All tables indexed by name */
  Hash idxHash;                 /* All (named) indices indexed by name */
  Hash tblDrop;                 /* Uncommitted DROP TABLEs */
  Hash idxDrop;                 /* Uncommitted DROP INDEXs */
  Hash userFunc;                /* User defined functions */
  int lastRowid;                /* ROWID of most recent insert */
  int priorNewRowid;            /* Last randomly generated ROWID */
  int onError;                  /* Default conflict algorithm */
};

/*
** Possible values for the sqlite.flags.
................................................................................
                                          /*   DELETE, or UPDATE and return */
                                          /*   the count using a callback. */
#define SQLITE_NullCallback   0x00000080  /* Invoke the callback once if the */
                                          /*   result set is empty */
#define SQLITE_ResultDetails  0x00000100  /* Details added to result set */

/*
** Each user-defined function is defined by an instance of the following
** structure.  A pointer to this structure is stored in the sqlite.userFunc
** hash table.  When multiple functions have the same name, the hash table
** points to a linked list of these structures.
*/
struct UserFunc {
  void (*xFunc)(sqlite_func*,int,const char**);   /* Regular function */
  void *(*xStep)(sqlite_func*,int,const char**);  /* Aggregate function step */
  void (*xFinalize)(sqlite_func*);           /* Aggregate function finializer */
  int nArg;                                  /* Number of arguments */
  void *pUserData;                           /* User data parameter */
  UserFunc *pNext;                           /* Next function with same name */
};

/*
** information about each column of an SQL table is held in an instance
** of this structure.
*/
struct Column {
................................................................................
** up.  Do not try to delete the expression attached to AggExpr.pExpr.
**
** If AggExpr.pExpr==0, that means the expression is "count(*)".
*/
struct AggExpr {
  int isAgg;        /* if TRUE contains an aggregate function */
  Expr *pExpr;      /* The expression */
  UserFunc *pUser;  /* User-defined aggregate function */
};

/*
** An SQL parser context.  A copy of this structure is passed through
** the parser and down into all the parser action routine in order to
** carry around information that is global to the entire parse.
*/
................................................................................
  int newTnum;         /* Table number to use when reparsing CREATE TABLEs */
  int nErr;            /* Number of errors seen */
  int nTab;            /* Number of previously allocated cursors */
  int nMem;            /* Number of memory cells used so far */
  int nSet;            /* Number of sets used so far */
  int nAgg;            /* Number of aggregate expressions */
  AggExpr *aAgg;       /* An array of aggregate expressions */
  int iAggCount;       /* Index of the count(*) aggregate in aAgg[] */
  int useAgg;          /* If true, extract field values from the aggregator
                       ** while generating expressions.  Normally false */
  int schemaVerified;  /* True if an OP_VerifySchema has been coded someplace
                       ** other than after an OP_Transaction */
};

/*
................................................................................
void sqliteExprMoveStrings(Expr*, int);
void sqliteExprListMoveStrings(ExprList*, int);
void sqliteSelectMoveStrings(Select*, int);
Expr *sqliteExprDup(Expr*);
ExprList *sqliteExprListDup(ExprList*);
IdList *sqliteIdListDup(IdList*);
Select *sqliteSelectDup(Select*);
UserFunc *sqliteFindUserFunction(sqlite*,const char*,int,int,int);
void sqliteRegisterBuildinFunctions(sqlite*);







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529
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531
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...
632
633
634
635
636
637
638
639
640
**    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.
**
*************************************************************************
** Internal interface definitions for SQLite.
**
** @(#) $Id: sqliteInt.h,v 1.96 2002/02/28 00:41:11 drh Exp $
*/
#include "sqlite.h"
#include "hash.h"
#include "vdbe.h"
#include "parse.h"
#include "btree.h"
#include <stdio.h>
................................................................................

/*
** A convenience macro that returns the number of elements in
** an array.
*/
#define ArraySize(X)    (sizeof(X)/sizeof(X[0]))
















/*
** Forward references to structures
*/
typedef struct Column Column;
typedef struct Table Table;
typedef struct Index Index;
typedef struct Instruction Instruction;
................................................................................
typedef struct Parse Parse;
typedef struct Token Token;
typedef struct IdList IdList;
typedef struct WhereInfo WhereInfo;
typedef struct WhereLevel WhereLevel;
typedef struct Select Select;
typedef struct AggExpr AggExpr;
typedef struct FuncDef FuncDef;

/*
** Each database is an instance of the following structure
*/
struct sqlite {
  Btree *pBe;                   /* The B*Tree backend */
  Btree *pBeTemp;               /* Backend for session temporary tables */
................................................................................
  int nTable;                   /* Number of tables in the database */
  void *pBusyArg;               /* 1st Argument to the busy callback */
  int (*xBusyCallback)(void *,const char*,int);  /* The busy callback */
  Hash tblHash;                 /* All tables indexed by name */
  Hash idxHash;                 /* All (named) indices indexed by name */
  Hash tblDrop;                 /* Uncommitted DROP TABLEs */
  Hash idxDrop;                 /* Uncommitted DROP INDEXs */
  Hash aFunc;                   /* All functions that can be in SQL exprs */
  int lastRowid;                /* ROWID of most recent insert */
  int priorNewRowid;            /* Last randomly generated ROWID */
  int onError;                  /* Default conflict algorithm */
};

/*
** Possible values for the sqlite.flags.
................................................................................
                                          /*   DELETE, or UPDATE and return */
                                          /*   the count using a callback. */
#define SQLITE_NullCallback   0x00000080  /* Invoke the callback once if the */
                                          /*   result set is empty */
#define SQLITE_ResultDetails  0x00000100  /* Details added to result set */

/*
** Each SQL function is defined by an instance of the following
** structure.  A pointer to this structure is stored in the sqlite.aFunc
** hash table.  When multiple functions have the same name, the hash table
** points to a linked list of these structures.
*/
struct FuncDef {
  void (*xFunc)(sqlite_func*,int,const char**);   /* Regular function */
  void *(*xStep)(sqlite_func*,int,const char**);  /* Aggregate function step */
  void (*xFinalize)(sqlite_func*);           /* Aggregate function finializer */
  int nArg;                                  /* Number of arguments */
  void *pUserData;                           /* User data parameter */
  FuncDef *pNext;                            /* Next function with same name */
};

/*
** information about each column of an SQL table is held in an instance
** of this structure.
*/
struct Column {
................................................................................
** up.  Do not try to delete the expression attached to AggExpr.pExpr.
**
** If AggExpr.pExpr==0, that means the expression is "count(*)".
*/
struct AggExpr {
  int isAgg;        /* if TRUE contains an aggregate function */
  Expr *pExpr;      /* The expression */
  FuncDef *pFunc;   /* Information about the aggregate function */
};

/*
** An SQL parser context.  A copy of this structure is passed through
** the parser and down into all the parser action routine in order to
** carry around information that is global to the entire parse.
*/
................................................................................
  int newTnum;         /* Table number to use when reparsing CREATE TABLEs */
  int nErr;            /* Number of errors seen */
  int nTab;            /* Number of previously allocated cursors */
  int nMem;            /* Number of memory cells used so far */
  int nSet;            /* Number of sets used so far */
  int nAgg;            /* Number of aggregate expressions */
  AggExpr *aAgg;       /* An array of aggregate expressions */

  int useAgg;          /* If true, extract field values from the aggregator
                       ** while generating expressions.  Normally false */
  int schemaVerified;  /* True if an OP_VerifySchema has been coded someplace
                       ** other than after an OP_Transaction */
};

/*
................................................................................
void sqliteExprMoveStrings(Expr*, int);
void sqliteExprListMoveStrings(ExprList*, int);
void sqliteSelectMoveStrings(Select*, int);
Expr *sqliteExprDup(Expr*);
ExprList *sqliteExprListDup(ExprList*);
IdList *sqliteIdListDup(IdList*);
Select *sqliteSelectDup(Select*);
FuncDef *sqliteFindFunction(sqlite*,const char*,int,int,int);
void sqliteRegisterBuildinFunctions(sqlite*);

Changes to src/util.c.

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**
*************************************************************************
** Utility functions used throughout sqlite.
**
** This file contains functions for allocating memory, comparing
** strings, and stuff like that.
**
** $Id: util.c,v 1.38 2002/02/27 01:47:12 drh Exp $
*/
#include "sqliteInt.h"
#include <stdarg.h>
#include <ctype.h>

/*
** If malloc() ever fails, this global variable gets set to 1.
................................................................................
**
** This is NOT the comparison function used for sorting.  The sort
** order is a little bit different.  See sqliteSortCompare below
** for additional information.
*/
int sqliteCompare(const char *atext, const char *btext){
  int result;






  int isNumA = isNum(atext);
  int isNumB = isNum(btext);
  if( isNumA ){
    if( !isNumB ){
      result = -1;
    }else{
      double rA, rB;
      rA = atof(atext);
      rB = atof(btext);







|







 







>
>
>
>
>
>
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**
*************************************************************************
** Utility functions used throughout sqlite.
**
** This file contains functions for allocating memory, comparing
** strings, and stuff like that.
**
** $Id: util.c,v 1.39 2002/02/28 00:41:11 drh Exp $
*/
#include "sqliteInt.h"
#include <stdarg.h>
#include <ctype.h>

/*
** If malloc() ever fails, this global variable gets set to 1.
................................................................................
**
** This is NOT the comparison function used for sorting.  The sort
** order is a little bit different.  See sqliteSortCompare below
** for additional information.
*/
int sqliteCompare(const char *atext, const char *btext){
  int result;
  int isNumA, isNumB;
  if( atext==0 ){
    return -(btext!=0);
  }else if( btext==0 ){
    return 1;
  }
  isNumA = isNum(atext);
  isNumB = isNum(btext);
  if( isNumA ){
    if( !isNumB ){
      result = -1;
    }else{
      double rA, rB;
      rA = atof(atext);
      rB = atof(btext);

Changes to src/vdbe.c.

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....
1057
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....
1861
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....
4400
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4402
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4405
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4410
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4416
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4418
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4421
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4424
4425
4426
4427
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....
4438
4439
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4451
4452
....
4605
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4611

4612
4613
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4617

4618
4619
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4622

4623
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4629
** type to the other occurs as necessary.
** 
** Most of the code in this file is taken up by the sqliteVdbeExec()
** function which does the work of interpreting a VDBE program.
** But other routines are also provided to help in building up
** a program instruction by instruction.
**
** $Id: vdbe.c,v 1.125 2002/02/27 19:50:59 drh Exp $
*/
#include "sqliteInt.h"
#include <ctype.h>

/*
** The following global variable is incremented every time a cursor
** moves, either by the OP_MoveTo or the OP_Next opcode.  The test
................................................................................
#define STK_Int       0x0004   /* Value is an integer */
#define STK_Real      0x0008   /* Value is a real number */
#define STK_Dyn       0x0010   /* Need to call sqliteFree() on zStack[*] */
#define STK_Static    0x0020   /* zStack[] points to a static string */

/* The following STK_ value appears only in AggElem.aMem.s.flag fields.
** It indicates that the corresponding AggElem.aMem.z points to a
** user-defined aggregate context that needs to be finalized.
*/
#define STK_AggCtx    0x0040   /* zStack[] points to an agg function context */

/*
** The "context" argument for a user-defined function.  A pointer to an
** instance of this structure is the first argument to the routines used
** implement user-defined SQL functions.
**
** There is a typedef for this structure in sqlite.h.  So all routines,
** even the public interface to SQLite, can use a pointer to this structure.
** But this file is the only place where the internal details of this
** structure are known.
**
** This structure is defined inside of vdbe.c because it uses substructures
** (Stack) which are only defined there.
*/
struct sqlite_func {
  UserFunc *pFunc;  /* Pointer to function information.  MUST BE FIRST */
  Stack s;          /* Small strings, ints, and double values go here */
  char *z;          /* Space for holding dynamic string results */
  void *pAgg;       /* Aggregate context */
  u8 isError;       /* Set to true for an error */
  u8 isStep;        /* Current in the step function */
  int cnt;          /* Number of times that the step function has been called */
};
................................................................................
typedef struct Agg Agg;
typedef struct AggElem AggElem;
struct Agg {
  int nMem;            /* Number of values stored in each AggElem */
  AggElem *pCurrent;   /* The AggElem currently in focus */
  HashElem *pSearch;   /* The hash element for pCurrent */
  Hash hash;           /* Hash table of all aggregate elements */
  UserFunc **apFunc;   /* Information about user-defined aggregate functions */
};
struct AggElem {
  char *zKey;          /* The key to this AggElem */
  int nKey;            /* Number of bytes in the key, including '\0' at end */
  Mem aMem[1];         /* The values for this AggElem */
};

................................................................................
    }
  }
  while( j>0 && isspace(z[j-1]) ){ j--; }
  z[j] = 0;
}

/*
** The following group or routines are employed by user-defined functions
** to return their results.
**
** The sqlite_set_result_string() routine can be used to return a string
** value or to return a NULL.  To return a NULL, pass in NULL for zResult.
** A copy is made of the string before this routine returns so it is safe
** to pass in a ephemeral string.
**
................................................................................
      p->pAgg = sqliteMalloc( nByte );
    }
  }
  return p->pAgg;
}

/*
** Return the number of times the Step function of a user-defined 
** aggregate has been called.
**
** This routine is defined here in vdbe.c because it depends on knowing
** the internals of the sqlite_func structure which is only defined in that
** one source file.
*/
int sqlite_aggregate_count(sqlite_func *p){
  assert( p && p->pFunc && p->pFunc->xStep );
  return p->cnt;
}

/*
** Reset an Agg structure.  Delete all its contents. 
**
** For user-defined aggregate functions, if the step function has been
** called, make sure the finalizer function has also been called.  The
** finalizer might need to free memory that was allocated as part of its
** private context.  If the finalizer has not been called yet, call it
** now.
*/
static void AggReset(Agg *pAgg){
  int i;
................................................................................
  "Subtract",          "Multiply",          "Divide",            "Remainder",
  "BitAnd",            "BitOr",             "BitNot",            "ShiftLeft",
  "ShiftRight",        "AbsValue",          "Precision",         "Min",
  "Max",               "Like",              "Glob",              "Eq",
  "Ne",                "Lt",                "Le",                "Gt",
  "Ge",                "IsNull",            "NotNull",           "Negative",
  "And",               "Or",                "Not",               "Concat",
  "Noop",              "Strlen",            "Substr",            "UserFunc",
  "Limit",           
};

/*
** Given the name of an opcode, return its number.  Return 0 if
** there is no match.
**
................................................................................
  }else{
    Release(p, tos);
  }
  p->tos = nos;
  break;
}

/* Opcode: UserFunc P1 * P3
**
** Invoke a user function (P3 is a pointer to a UserFunc structure that
** defines the function) with P1 string arguments taken from the stack.
** Pop all arguments from the stack and push back the result.
**
** See also: AggFunc
*/
case OP_UserFunc: {
  int n, i;
  sqlite_func ctx;

  n = pOp->p1;
  VERIFY( if( n<=0 ) goto bad_instruction; )
  VERIFY( if( p->tos+1<n ) goto not_enough_stack; )
  for(i=p->tos-n+1; i<=p->tos; i++){
    if( (aStack[i].flags & STK_Null)==0 ){
      if( Stringify(p, i) ) goto no_mem;
    }
  }
  ctx.pFunc = (UserFunc*)pOp->p3;
  ctx.s.flags = STK_Null;
  ctx.z = 0;
  ctx.isError = 0;
  ctx.isStep = 0;
  (*ctx.pFunc->xFunc)(&ctx, n, (const char**)&zStack[p->tos-n+1]);
  PopStack(p, n);
  VERIFY( NeedStack(p, p->tos+1); )
................................................................................
  p->agg.nMem = pOp->p2;
  p->agg.apFunc = sqliteMalloc( p->agg.nMem*sizeof(p->agg.apFunc[0]) );
  break;
}

/* Opcode: AggInit * P2 P3
**
** Initialize the function parameters for a user-defined aggregate function.
** The user-defined aggregate will operate out of aggregate column P2.
** P3 is a pointer to the UserFunc structure for the function.
*/
case OP_AggInit: {
  int i = pOp->p2;
  VERIFY( if( i<0 || i>=p->agg.nMem ) goto bad_instruction; )
  p->agg.apFunc[i] = (UserFunc*)pOp->p3;
  break;
}

/* Opcode: AggFunc * P2 P3
**
** Execute the step function for a user-defined aggregate.  The
** function has P2 arguments.  P3 is a pointer to the UserFunc
** structure that specifies the user-defined function.
**
** The top of the stack must be an integer which is the index of
** the aggregate column that corresponds to this aggregate function.
** Ideally, this index would be another parameter, but there are
** no free parameters left.  The integer is popped from the stack.
*/
case OP_AggFunc: {
................................................................................
  for(i=p->tos-n; i<p->tos; i++){
    if( (aStack[i].flags & STK_Null)==0 ){
      if( Stringify(p, i) ) goto no_mem;
    }
  }
  i = aStack[p->tos].i;
  VERIFY( if( i<0 || i>=p->agg.nMem ) goto bad_instruction; )
  ctx.pFunc = (UserFunc*)pOp->p3;
  pMem = &p->agg.pCurrent->aMem[i];
  ctx.z = pMem->s.z;
  ctx.pAgg = pMem->z;
  ctx.cnt = ++pMem->s.i;
  ctx.isError = 0;
  ctx.isStep = 1;
  (ctx.pFunc->xStep)(&ctx, n, (const char**)&zStack[p->tos-n]);
................................................................................
    int i;
    sqlite_func ctx;
    Mem *aMem;
    int nErr = 0;
    p->agg.pCurrent = sqliteHashData(p->agg.pSearch);
    aMem = p->agg.pCurrent->aMem;
    for(i=0; i<p->agg.nMem; i++){

      if( p->agg.apFunc[i]==0 ) continue;
      if( p->agg.apFunc[i]->xFinalize==0 ) continue;
      if( (aMem[i].s.flags & STK_AggCtx)==0 ) continue;
      ctx.s.flags = STK_Null;
      ctx.z = 0;
      ctx.pAgg = (void*)aMem[i].z;

      ctx.cnt = aMem[i].s.i;
      ctx.isStep = 0;
      ctx.pFunc = p->agg.apFunc[i];
      (*p->agg.apFunc[i]->xFinalize)(&ctx);

      sqliteFree( aMem[i].z );

      aMem[i].s = ctx.s;
      aMem[i].z = ctx.z;
      if( (aMem[i].s.flags & STK_Str) &&
              (aMem[i].s.flags & (STK_Dyn|STK_Static))==0 ){
        aMem[i].z = aMem[i].s.z;
      }
      nErr += ctx.isError;







|







 







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26
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637
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....
1057
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1071
....
1861
1862
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....
4400
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4403
4404
4405
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4409
4410
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4423
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4425
4426
4427
4428
4429
....
4438
4439
4440
4441
4442
4443
4444
4445
4446
4447
4448
4449
4450
4451
4452
....
4605
4606
4607
4608
4609
4610
4611
4612
4613
4614
4615
4616
4617
4618
4619
4620
4621
4622
4623
4624
4625
4626
4627
4628
4629
4630
4631
4632
4633
** type to the other occurs as necessary.
** 
** Most of the code in this file is taken up by the sqliteVdbeExec()
** function which does the work of interpreting a VDBE program.
** But other routines are also provided to help in building up
** a program instruction by instruction.
**
** $Id: vdbe.c,v 1.126 2002/02/28 00:41:11 drh Exp $
*/
#include "sqliteInt.h"
#include <ctype.h>

/*
** The following global variable is incremented every time a cursor
** moves, either by the OP_MoveTo or the OP_Next opcode.  The test
................................................................................
#define STK_Int       0x0004   /* Value is an integer */
#define STK_Real      0x0008   /* Value is a real number */
#define STK_Dyn       0x0010   /* Need to call sqliteFree() on zStack[*] */
#define STK_Static    0x0020   /* zStack[] points to a static string */

/* The following STK_ value appears only in AggElem.aMem.s.flag fields.
** It indicates that the corresponding AggElem.aMem.z points to a
** aggregate function context that needs to be finalized.
*/
#define STK_AggCtx    0x0040   /* zStack[] points to an agg function context */

/*
** The "context" argument for a installable function.  A pointer to an
** instance of this structure is the first argument to the routines used
** implement the SQL functions.
**
** There is a typedef for this structure in sqlite.h.  So all routines,
** even the public interface to SQLite, can use a pointer to this structure.
** But this file is the only place where the internal details of this
** structure are known.
**
** This structure is defined inside of vdbe.c because it uses substructures
** (Stack) which are only defined there.
*/
struct sqlite_func {
  FuncDef *pFunc;   /* Pointer to function information.  MUST BE FIRST */
  Stack s;          /* Small strings, ints, and double values go here */
  char *z;          /* Space for holding dynamic string results */
  void *pAgg;       /* Aggregate context */
  u8 isError;       /* Set to true for an error */
  u8 isStep;        /* Current in the step function */
  int cnt;          /* Number of times that the step function has been called */
};
................................................................................
typedef struct Agg Agg;
typedef struct AggElem AggElem;
struct Agg {
  int nMem;            /* Number of values stored in each AggElem */
  AggElem *pCurrent;   /* The AggElem currently in focus */
  HashElem *pSearch;   /* The hash element for pCurrent */
  Hash hash;           /* Hash table of all aggregate elements */
  FuncDef **apFunc;    /* Information about aggregate functions */
};
struct AggElem {
  char *zKey;          /* The key to this AggElem */
  int nKey;            /* Number of bytes in the key, including '\0' at end */
  Mem aMem[1];         /* The values for this AggElem */
};

................................................................................
    }
  }
  while( j>0 && isspace(z[j-1]) ){ j--; }
  z[j] = 0;
}

/*
** The following group or routines are employed by installable functions
** to return their results.
**
** The sqlite_set_result_string() routine can be used to return a string
** value or to return a NULL.  To return a NULL, pass in NULL for zResult.
** A copy is made of the string before this routine returns so it is safe
** to pass in a ephemeral string.
**
................................................................................
      p->pAgg = sqliteMalloc( nByte );
    }
  }
  return p->pAgg;
}

/*
** Return the number of times the Step function of a aggregate has been 
** called.
**
** This routine is defined here in vdbe.c because it depends on knowing
** the internals of the sqlite_func structure which is only defined in that
** one source file.
*/
int sqlite_aggregate_count(sqlite_func *p){
  assert( p && p->pFunc && p->pFunc->xStep );
  return p->cnt;
}

/*
** Reset an Agg structure.  Delete all its contents. 
**
** For installable aggregate functions, if the step function has been
** called, make sure the finalizer function has also been called.  The
** finalizer might need to free memory that was allocated as part of its
** private context.  If the finalizer has not been called yet, call it
** now.
*/
static void AggReset(Agg *pAgg){
  int i;
................................................................................
  "Subtract",          "Multiply",          "Divide",            "Remainder",
  "BitAnd",            "BitOr",             "BitNot",            "ShiftLeft",
  "ShiftRight",        "AbsValue",          "Precision",         "Min",
  "Max",               "Like",              "Glob",              "Eq",
  "Ne",                "Lt",                "Le",                "Gt",
  "Ge",                "IsNull",            "NotNull",           "Negative",
  "And",               "Or",                "Not",               "Concat",
  "Noop",              "Strlen",            "Substr",            "Function",
  "Limit",           
};

/*
** Given the name of an opcode, return its number.  Return 0 if
** there is no match.
**
................................................................................
  }else{
    Release(p, tos);
  }
  p->tos = nos;
  break;
}

/* Opcode: Function P1 * P3
**
** Invoke a user function (P3 is a pointer to a Function structure that
** defines the function) with P1 string arguments taken from the stack.
** Pop all arguments from the stack and push back the result.
**
** See also: AggFunc
*/
case OP_Function: {
  int n, i;
  sqlite_func ctx;

  n = pOp->p1;
  VERIFY( if( n<=0 ) goto bad_instruction; )
  VERIFY( if( p->tos+1<n ) goto not_enough_stack; )
  for(i=p->tos-n+1; i<=p->tos; i++){
    if( (aStack[i].flags & STK_Null)==0 ){
      if( Stringify(p, i) ) goto no_mem;
    }
  }
  ctx.pFunc = (FuncDef*)pOp->p3;
  ctx.s.flags = STK_Null;
  ctx.z = 0;
  ctx.isError = 0;
  ctx.isStep = 0;
  (*ctx.pFunc->xFunc)(&ctx, n, (const char**)&zStack[p->tos-n+1]);
  PopStack(p, n);
  VERIFY( NeedStack(p, p->tos+1); )
................................................................................
  p->agg.nMem = pOp->p2;
  p->agg.apFunc = sqliteMalloc( p->agg.nMem*sizeof(p->agg.apFunc[0]) );
  break;
}

/* Opcode: AggInit * P2 P3
**
** Initialize the function parameters for an aggregate function.
** The aggregate will operate out of aggregate column P2.
** P3 is a pointer to the FuncDef structure for the function.
*/
case OP_AggInit: {
  int i = pOp->p2;
  VERIFY( if( i<0 || i>=p->agg.nMem ) goto bad_instruction; )
  p->agg.apFunc[i] = (FuncDef*)pOp->p3;
  break;
}

/* Opcode: AggFunc * P2 P3
**
** Execute the step function for an aggregate.  The
** function has P2 arguments.  P3 is a pointer to the FuncDef
** structure that specifies the function.
**
** The top of the stack must be an integer which is the index of
** the aggregate column that corresponds to this aggregate function.
** Ideally, this index would be another parameter, but there are
** no free parameters left.  The integer is popped from the stack.
*/
case OP_AggFunc: {
................................................................................
  for(i=p->tos-n; i<p->tos; i++){
    if( (aStack[i].flags & STK_Null)==0 ){
      if( Stringify(p, i) ) goto no_mem;
    }
  }
  i = aStack[p->tos].i;
  VERIFY( if( i<0 || i>=p->agg.nMem ) goto bad_instruction; )
  ctx.pFunc = (FuncDef*)pOp->p3;
  pMem = &p->agg.pCurrent->aMem[i];
  ctx.z = pMem->s.z;
  ctx.pAgg = pMem->z;
  ctx.cnt = ++pMem->s.i;
  ctx.isError = 0;
  ctx.isStep = 1;
  (ctx.pFunc->xStep)(&ctx, n, (const char**)&zStack[p->tos-n]);
................................................................................
    int i;
    sqlite_func ctx;
    Mem *aMem;
    int nErr = 0;
    p->agg.pCurrent = sqliteHashData(p->agg.pSearch);
    aMem = p->agg.pCurrent->aMem;
    for(i=0; i<p->agg.nMem; i++){
      int freeCtx;
      if( p->agg.apFunc[i]==0 ) continue;
      if( p->agg.apFunc[i]->xFinalize==0 ) continue;
      if( (aMem[i].s.flags & STK_AggCtx)==0 ) continue;
      ctx.s.flags = STK_Null;
      ctx.z = 0;
      ctx.pAgg = (void*)aMem[i].z;
      freeCtx = aMem[i].z && aMem[i].z!=aMem[i].s.z;
      ctx.cnt = aMem[i].s.i;
      ctx.isStep = 0;
      ctx.pFunc = p->agg.apFunc[i];
      (*p->agg.apFunc[i]->xFinalize)(&ctx);
      if( freeCtx ){
        sqliteFree( aMem[i].z );
      }
      aMem[i].s = ctx.s;
      aMem[i].z = ctx.z;
      if( (aMem[i].s.flags & STK_Str) &&
              (aMem[i].s.flags & (STK_Dyn|STK_Static))==0 ){
        aMem[i].z = aMem[i].s.z;
      }
      nErr += ctx.isError;

Changes to src/vdbe.h.

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*************************************************************************
** Header file for the Virtual DataBase Engine (VDBE)
**
** This header defines the interface to the virtual database engine
** or VDBE.  The VDBE implements an abstract machine that runs a
** simple program to access and modify the underlying database.
**
** $Id: vdbe.h,v 1.47 2002/02/27 19:00:22 drh Exp $
*/
#ifndef _SQLITE_VDBE_H_
#define _SQLITE_VDBE_H_
#include <stdio.h>

/*
** A single VDBE is an opaque structure named "Vdbe".  Only routines
................................................................................
#define OP_And               113
#define OP_Or                114
#define OP_Not               115
#define OP_Concat            116
#define OP_Noop              117
#define OP_Strlen            118
#define OP_Substr            119
#define OP_UserFunc          120

#define OP_Limit             121

#define OP_MAX               121

/*
** Prototypes for the VDBE interface.  See comments on the implementation







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*************************************************************************
** Header file for the Virtual DataBase Engine (VDBE)
**
** This header defines the interface to the virtual database engine
** or VDBE.  The VDBE implements an abstract machine that runs a
** simple program to access and modify the underlying database.
**
** $Id: vdbe.h,v 1.48 2002/02/28 00:41:11 drh Exp $
*/
#ifndef _SQLITE_VDBE_H_
#define _SQLITE_VDBE_H_
#include <stdio.h>

/*
** A single VDBE is an opaque structure named "Vdbe".  Only routines
................................................................................
#define OP_And               113
#define OP_Or                114
#define OP_Not               115
#define OP_Concat            116
#define OP_Noop              117
#define OP_Strlen            118
#define OP_Substr            119
#define OP_Function          120

#define OP_Limit             121

#define OP_MAX               121

/*
** Prototypes for the VDBE interface.  See comments on the implementation