SQLite

** Author contact information:
**   drh@hwaci.com
**   http://www.hwaci.com/drh/
**
*************************************************************************
** This file contains C code routines used for processing expressions
**
** $Id: expr.c,v 1.5 2000/06/04 12:58:37 drh Exp $
*/
#include "sqliteInt.h"

/*
** This routine walks an expression tree and resolves references to
** table fields.  Nodes of the form ID.ID or ID resolve into an
** index to the table in the table list and a field offset.  The opcode

    case TK_STRING: {
      int addr = sqliteVdbeAddOp(v, OP_String, 0, 0, 0, 0);
      sqliteVdbeChangeP3(v, addr, pExpr->token.z, pExpr->token.n);
      sqliteVdbeDequoteP3(v, addr);
      break;
    }
    case TK_NULL: {
      sqliteVdbeAddOp(v, OP_Null, 0, 0, 0, 0);
      break;
    }
    case TK_AND:
    case TK_OR:
    case TK_PLUS:
    case TK_STAR:
    case TK_MINUS:

**   drh@hwaci.com
**   http://www.hwaci.com/drh/
**
*************************************************************************
** This file contains C code routines that are called by the parser
** to handle INSERT statements.
**
** $Id: insert.c,v 1.5 2000/06/04 12:58:38 drh Exp $
*/
#include "sqliteInt.h"

/*
** This routine is call to handle SQL of the following form:
**
**    insert into TABLE (IDLIST) values(EXPRLIST)

      }else{
        for(j=0; j<pField->nId; j++){
          if( pField->a[j].idx==i ) break;
        }
      }
      if( pField && j>=pField->nId ){
        char *zDflt = pTab->aCol[i].zDflt;
        if( zDflt==0 ){
          sqliteVdbeAddOp(v, OP_Null, 0, 0, 0, 0);
        }else{
          sqliteVdbeAddOp(v, OP_String, 0, 0, zDflt, 0);
        }
      }else{
        sqliteExprCode(pParse, pList->a[j].pExpr);
      }
    }
    sqliteVdbeAddOp(v, OP_MakeRecord, pTab->nCol, 0, 0, 0);
    sqliteVdbeAddOp(v, OP_Put, 0, 0, 0, 0);
    sqliteVdbeAddOp(v, OP_Close, 0, 0, 0, 0);

        }else{
          for(j=0; j<pField->nId; j++){
            if( pField->a[j].idx==idx ) break;
          }
        }
        if( pField && j>=pField->nId ){
          char *zDflt = pTab->aCol[idx].zDflt;
          if( zDflt==0 ){
            sqliteVdbeAddOp(v, OP_Null, 0, 0, 0, 0);
          }else{
            sqliteVdbeAddOp(v, OP_String, 0, 0, zDflt, 0);
          }
        }else{
          sqliteExprCode(pParse, pList->a[j].pExpr);
        }
      }
      sqliteVdbeAddOp(v, OP_MakeKey, pIdx->nField, 0, 0, 0);
      sqliteVdbeAddOp(v, OP_PutIdx, idx, 0, 0, 0);
      sqliteVdbeAddOp(v, OP_Close, idx, 0, 0, 0);

**   drh@hwaci.com
**   http://www.hwaci.com/drh/
**
*************************************************************************
** This file contains C code routines that are called by the parser
** to handle SELECT statements.
**
** $Id: select.c,v 1.6 2000/06/04 12:58:38 drh Exp $
*/
#include "sqliteInt.h"


/*
** Process a SELECT statement.
*/

  */
  if( isAgg ){
    for(i=0; i<pEList->nExpr; i++){
      Expr *p = pEList->a[i].pExpr;
      switch( sqliteFuncId(&p->token) ){
        case FN_Min:
        case FN_Max: {
          sqliteVdbeAddOp(v, OP_Null, 0, 0, 0, 0);
          break;
        }
        default: {
          sqliteVdbeAddOp(v, OP_Integer, 0, 0, 0, 0);
          break;
        }
      }

      int id = sqliteFuncId(&p->token);
      int op, p1;
      if( n>1 ){
        sqliteVdbeAddOp(v, OP_Pull, n-1, 0, 0, 0);
      }
      if( id!=FN_Count && p->pList && p->pList->nExpr>=1 ){
        sqliteExprCode(pParse, p->pList->a[0].pExpr);
        sqliteVdbeAddOp(v, OP_Concat, 1, 0, 0, 0);
      }
      switch( sqliteFuncId(&p->token) ){
        case FN_Count: op = OP_AddImm; p1 = 1; break;
        case FN_Sum:   op = OP_Add;    p1 = 0; break;
        case FN_Min:   op = OP_Min;    p1 = 1; break;
        case FN_Max:   op = OP_Max;    p1 = 0; break;
      }

**   drh@hwaci.com
**   http://www.hwaci.com/drh/
**
*************************************************************************
** This file contains code to implement the "sqlite" command line
** utility for accessing SQLite databases.
**
** $Id: shell.c,v 1.7 2000/06/04 12:58:38 drh Exp $
*/
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include "sqlite.h"
#include <unistd.h>
#include <ctype.h>

static int callback(void *pArg, int nArg, char **azArg, char **azCol){
  int i;
  struct callback_data *p = (struct callback_data*)pArg;
  switch( p->mode ){
    case MODE_Line: {
      if( p->cnt++>0 ) fprintf(p->out,"\n");
      for(i=0; i<nArg; i++){
        fprintf(p->out,"%s = %s\n", azCol[i], azArg[i] ? azArg[i] : 0);
      }
      break;
    }
    case MODE_Column: {
      if( p->cnt++==0 && p->showHeader ){
        for(i=0; i<nArg; i++){
          int w;

      for(i=0; i<nArg; i++){
        int w;
        if( i<ArraySize(p->colWidth) && p->colWidth[i]>0 ){
           w = p->colWidth[i];
        }else{
           w = 10;
        }
        fprintf(p->out,"%-*.*s%s",w,w,
            azArg[i] ? azArg[i] : "", i==nArg-1 ? "\n": "  ");
      }
      break;
    }
    case MODE_List: {
      if( p->cnt++==0 && p->showHeader ){
        for(i=0; i<nArg; i++){
          fprintf(p->out,"%s%s",azCol[i], i==nArg-1 ? "\n" : p->separator);
        }
      }
      for(i=0; i<nArg; i++){
        fprintf(p->out,"%s%s",azArg[i] ? azArg[i] : "",
             i==nArg-1 ? "\n" : p->separator);
      }
      break;
    }
    case MODE_Html: {
      if( p->cnt++==0 && p->showHeader ){
        fprintf(p->out,"<TR>");
        for(i=0; i<nArg; i++){
          fprintf(p->out,"<TH>%s</TH>",azCol[i]);
        }
        fprintf(p->out,"</TR>\n");
      }
      for(i=0; i<nArg; i++){
        fprintf(p->out,"<TR>");
        for(i=0; i<nArg; i++){
          fprintf(p->out,"<TD>%s</TD>",azArg[i] ? azArg[i] : "");
        }
        fprintf(p->out,"</TD>\n");
      }
      break;
    }
  }      
  return 0;

** Author contact information:
**   drh@hwaci.com
**   http://www.hwaci.com/drh/
**
*************************************************************************
** Internal interface definitions for SQLite.
**
** @(#) $Id: sqliteInt.h,v 1.12 2000/06/04 12:58:38 drh Exp $
*/
#include "sqlite.h"
#include "dbbe.h"
#include "vdbe.h"
#include "parse.h"
#include <gdbm.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <assert.h>

#define MEMORY_DEBUG 1
#ifdef MEMORY_DEBUG
# define sqliteMalloc(X)    sqliteMalloc_(X,__FILE__,__LINE__)
# define sqliteFree(X)      sqliteFree_(X,__FILE__,__LINE__)
# define sqliteRealloc(X,Y) sqliteRealloc_(X,Y,__FILE__,__LINE__)
  void sqliteStrRealloc(char**);
#else
# define sqliteStrRealloc(X)

** Author contact information:
**   drh@hwaci.com
**   http://www.hwaci.com/drh/
**
*************************************************************************
** A TCL Interface to SQLite
**
** $Id: tclsqlite.c,v 1.5 2000/06/04 12:58:38 drh Exp $
*/
#include "sqlite.h"
#include <tcl.h>
#include <stdlib.h>
#include <string.h>

/*

    if( cbData->once ){
      for(i=0; i<nCol; i++){
        Tcl_SetVar2(cbData->interp, cbData->zArray, "*", azN[i],
           TCL_LIST_ELEMENT|TCL_APPEND_VALUE);
      }
    }
    for(i=0; i<nCol; i++){
      char *z = azCol[i];
      if( z==0 ) z = "";
      Tcl_SetVar2(cbData->interp, cbData->zArray, azN[i], z, 0);
    }
  }else{
    for(i=0; i<nCol; i++){
      char *z = azCol[i];
      if( z==0 ) z = "";
      Tcl_SetVar(cbData->interp, azN[i], z, 0);
    }
  }
  cbData->once = 0;
  rc = Tcl_Eval(cbData->interp, cbData->zCode);
  return rc;
}

    Tcl_SetVar(interp,"argv0",argv[1],TCL_GLOBAL_ONLY);
    Tcl_SetVar(interp,"argv", "", TCL_GLOBAL_ONLY);
    for(i=2; i<argc; i++){
      Tcl_SetVar(interp, "argv", argv[i],
          TCL_GLOBAL_ONLY | TCL_LIST_ELEMENT | TCL_APPEND_VALUE);
    }
    if( Tcl_EvalFile(interp, argv[1])!=TCL_OK ){

      char *zInfo = Tcl_GetVar(interp, "errorInfo", TCL_GLOBAL_ONLY);
      if( zInfo==0 ) zInfo = interp->result;
      fprintf(stderr,"%s: %s\n", *argv, zInfo);
      return 1;
    }
  }else{
    Tcl_GlobalEval(interp, zMainloop);
  }
  return 0;
}
#endif /* TCLSH */

**
*************************************************************************
** Utility functions used throughout sqlite.
**
** This file contains functions for allocating memory, comparing
** strings, and stuff like that.
**
** $Id: util.c,v 1.10 2000/06/04 12:58:38 drh Exp $
*/
#include "sqliteInt.h"
#include <stdarg.h>
#include <ctype.h>

#ifdef MEMORY_DEBUG

          while( *zString && sqliteGlobCompare(&zPattern[1],zString)==0 ){
            zString++;
          }
          return *zString!=0;
        }else{
          while( (c2 = *zString)!=0 ){
            while( c2 != 0 && c2 != c ){ c2 = *++zString; }
            if( c2==0 ) return 0;
            if( sqliteGlobCompare(&zPattern[1],zString) ) return 1;
            zString++;
          }
          return 0;
        }
      case '?':
        if( *zString==0 ) return 0;

          while( *zString && sqliteLikeCompare(&zPattern[1],zString)==0 ){
            zString++;
          }
          return *zString!=0;
        }else{
          while( (c2 = UpperToLower[*zString])!=0 ){
            while( c2 != 0 && c2 != c ){ c2 = UpperToLower[*++zString]; }
            if( c2==0 ) return 0;
            if( sqliteLikeCompare(&zPattern[1],zString) ) return 1;
            zString++;
          }
          return 0;
        }
      case '_':
        if( *zString==0 ) return 0;

** inplicit conversion from one 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 1.13 2000/06/04 12:58:38 drh Exp $
*/
#include "sqliteInt.h"

/*
** SQL is translated into a sequence of instructions to be
** executed by a virtual machine.  Each instruction is an instance
** of the following structure.

};

/* 
** Number of buckets used for merge-sort.  
*/
#define NSORT 30

/*
** A single level of the stack is an instance of the following
** structure.  Except, string values are stored on a separate
** list of of pointers to character.  The reason for storing
** strings separately is so that they can be easily passed
** to the callback function.
*/
struct Stack {
  int i;         /* Integer value */
  int n;         /* Number of characters in string value, including '\0' */
  int flags;     /* Some combination of STK_Null, STK_Str, STK_Dyn, etc. */
  double r;      /* Real value */      
};
typedef struct Stack Stack;

/*
** Allowed values for Stack.flags
*/
#define STK_Null      0x0001   /* Value is NULL */
#define STK_Str       0x0002   /* Value is a string */
#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[*] */

/*
** An instance of the virtual machine
*/
struct Vdbe {
  Dbbe *pBe;          /* Opaque context structure used by DB backend */
  FILE *trace;        /* Write an execution trace here, if not NULL */
  int nOp;            /* Number of instructions in the program */
  int nOpAlloc;       /* Number of slots allocated for aOp[] */
  Op *aOp;            /* Space to hold the virtual machine's program */
  int nLabel;         /* Number of labels used */
  int nLabelAlloc;    /* Number of slots allocated in aLabel[] */
  int *aLabel;        /* Space to hold the labels */
  int tos;            /* Index of top of stack */
  int nStackAlloc;    /* Size of the stack */
  Stack *aStack;      /* The operand stack, except string values */
  char **zStack;      /* Text or binary values of the stack */
  char **azColName;   /* Becomes the 4th parameter to callbacks */
  int nTable;         /* Number of slots in aTab[] */
  VdbeTable *aTab;    /* On element of this array for each open table */
  int nList;          /* Number of slots in apList[] */
  FILE **apList;      /* An open file for each list */
  int nSort;          /* Number of slots in apSort[] */

    p->nLabel = 0;
    p->nLabelAlloc = 0;
    return 0;
  }
  p->aLabel[i] = -1;
  return -1-i;
}

/*
** Convert the given stack entity into a string if it isn't one
** already.  Return non-zero if we run out of memory.
**
** NULLs are converted into an empty string.
*/
#define Stringify(P,I) \
   ((P->aStack[I].flags & STK_Str)==0 ? hardStringify(P,I) : 0)
static int hardStringify(Vdbe *p, int i){
  char zBuf[30];
  int fg = p->aStack[i].flags;
  if( fg & STK_Real ){
    sprintf(zBuf,"%g",p->aStack[i].r);
  }else if( fg & STK_Int ){
    sprintf(zBuf,"%d",p->aStack[i].i);
  }else{
    p->zStack[i] = "";
    p->aStack[i].n = 1;
    p->aStack[i].flags |= STK_Str;
    return 0;
  }
  p->zStack[i] = 0;
  sqliteSetString(&p->zStack[i], zBuf, 0);
  if( p->zStack[i]==0 ) return 1;
  p->aStack[i].n = strlen(p->zStack[i])+1;
  p->aStack[i].flags |= STK_Str|STK_Dyn;
  return 0;
}

/*
** Release the memory associated with the given stack level
*/
#define Release(P,I)  if((P)->aStack[I].flags&STK_Dyn){ hardRelease(P,I); }
static void hardRelease(Vdbe *p, int i){
  sqliteFree(p->zStack[i]);
  p->zStack[i] = 0;
  p->aStack[i].flags &= ~(STK_Str|STK_Dyn);
}

/*
** Convert the given stack entity into a integer if it isn't one
** already.
**
** Any prior string or real representation is invalidated.  
** NULLs are converted into 0.
*/
#define Integerify(P,I) \
    if(((P)->aStack[(I)].flags&STK_Int)==0){ hardIntegerify(P,I); }
static void hardIntegerify(Vdbe *p, int i){
  if( p->aStack[i].flags & STK_Real ){
    p->aStack[i].i = p->aStack[i].r;
    Release(p, i);
  }else if( p->aStack[i].flags & STK_Str ){
    p->aStack[i].i = atoi(p->zStack[i]);
    Release(p, i);
  }else{
    p->aStack[i].i = 0;
  }
  p->aStack[i].flags = STK_Int;
}

/*
** Get a valid Real representation for the given stack element.
**
** Any prior string or integer representation is retained.
** NULLs are converted into 0.0.
*/
#define Realify(P,I) \
    if(((P)->aStack[(I)].flags&STK_Real)==0){ hardRealify(P,I); }
static void hardRealify(Vdbe *p, int i){
  if( p->aStack[i].flags & STK_Str ){
    p->aStack[i].r = atof(p->zStack[i]);
  }else if( p->aStack[i].flags & STK_Int ){
    p->aStack[i].r = p->aStack[i].i;
  }else{
    p->aStack[i].r = 0.0;
  }
  p->aStack[i].flags |= STK_Real;
}

/*
** Pop the stack N times.  Free any memory associated with the
** popped stack elements.
*/
static void PopStack(Vdbe *p, int N){
  if( p->zStack==0 ) return;
  while( p->tos>=0 && N-->0 ){
    int i = p->tos--;
    if( p->aStack[i].flags & STK_Dyn ){
      sqliteFree(p->zStack[i]);
    }
    p->aStack[i].flags = 0;
    p->zStack[i] = 0;
  }    
}

/*
** Make sure space has been allocated to hold at least N
** stack elements.  Allocate additional stack space if
** necessary.
**
** Return 0 on success and non-zero if there are memory
** allocation errors.
*/
#define NeedStack(P,N) (((P)->nStackAlloc<=(N)) ? hardNeedStack(P,N) : 0)
static int hardNeedStack(Vdbe *p, int N){
  int oldAlloc;
  int i;
  if( N>=p->nStackAlloc ){
    oldAlloc = p->nStackAlloc;
    p->nStackAlloc = N + 20;
    p->aStack = sqliteRealloc(p->aStack, p->nStackAlloc*sizeof(p->aStack[0]));
    p->zStack = sqliteRealloc(p->zStack, p->nStackAlloc*sizeof(char*));
    if( p->aStack==0 || p->zStack==0 ){
      sqliteFree(p->aStack);
      sqliteFree(p->zStack);
      p->aStack = 0;
      p->zStack = 0;
      p->nStackAlloc = 0;
      return 1;
    }
    for(i=oldAlloc; i<p->nStackAlloc; i++){
      p->zStack[i] = 0;
      p->aStack[i].flags = 0;
    }
  }
  return 0;
}

/*
** Clean up the VM after execution.
**
** This routine will automatically close any tables, list, and/or
** sorters that were left open.
*/

    p->nOp = 0;
  }
  for(i=0; i<p->nOp; i++){
    sqliteFree(p->aOp[i].p3);
  }
  sqliteFree(p->aOp);
  sqliteFree(p->aLabel);
  sqliteFree(p->aStack);
  sqliteFree(p->zStack);
  sqliteFree(p);
}

/*
** A translation from opcode numbers to opcode names.  Used for testing
** and debugging only.

  "DeleteIdx",      "ListOpen",       "ListWrite",      "ListRewind",
  "ListRead",       "ListClose",      "SortOpen",       "SortPut",
  "SortMakeRec",    "SortMakeKey",    "Sort",           "SortNext",
  "SortKey",        "SortCallback",   "SortClose",      "FileOpen",
  "FileRead",       "FileField",      "FileClose",      "MakeRecord",
  "MakeKey",        "Goto",           "If",             "Halt",
  "ColumnCount",    "ColumnName",     "Callback",       "Integer",
  "String",         "Null",           "Pop",            "Dup",
  "Pull",           "Add",            "AddImm",         "Subtract",
  "Multiply",       "Divide",         "Min",            "Max",
  "Like",           "Glob",           "Eq",             "Ne",
  "Lt",             "Le",             "Gt",             "Ge",
  "IsNull",         "NotNull",        "Negative",       "And",
  "Or",             "Not",            "Concat",         "Noop",
};

/*
** Given the name of an opcode, return its number.  Return 0 if
** there is no match.
**
** This routine is used for testing and debugging.

  rc = SQLITE_OK;
  if( pzErrMsg ){ *pzErrMsg = 0; }
  for(i=0; rc==SQLITE_OK && i<p->nOp; i++){
    sprintf(zAddr,"%d",i);
    sprintf(zP1,"%d", p->aOp[i].p1);
    sprintf(zP2,"%d", p->aOp[i].p2);
    azField[4] = p->aOp[i].p3;

    azField[1] = zOpName[p->aOp[i].opcode];
    if( xCallback(pArg, 5, azField, azColumnNames) ){
      rc = SQLITE_ABORT;
    }
  }
  return rc;
}




























































/*
** The parameters are pointers to the head of two sorted lists
** of Sorter structures.  Merge these two lists together and return
** a single sorted list.  This routine forms the core of the merge-sort
** algorithm.
**
** In the case of a tie, left sorts in front of right.

      /* Opcode: Integer P1 * *
      **
      ** The integer value P1 is pushed onto the stack.
      */
      case OP_Integer: {
        int i = ++p->tos;
        if( NeedStack(p, p->tos) ) goto no_mem;
        p->aStack[i].i = pOp->p1;
        p->aStack[i].flags = STK_Int;
        break;
      }

      /* Opcode: String * * P3
      **
      ** The string value P3 is pushed onto the stack.
      */
      case OP_String: {
        int i = ++p->tos;
        char *z;
        if( NeedStack(p, p->tos) ) goto no_mem;
        z = pOp->p3;
        if( z==0 ) z = "";
        p->zStack[i] = z;
        p->aStack[i].n = strlen(z) + 1;
        p->aStack[i].flags = STK_Str;
        break;
      }

      /* Opcode: NULL * * *
      **
      ** Push a NULL value onto the stack.
      */
      case OP_Null: {
        int i = ++p->tos;
        char *z;
        if( NeedStack(p, p->tos) ) goto no_mem;
        p->zStack[i] = 0;
        p->aStack[i].flags = STK_Null;
        break;
      }

      /* Opcode: Pop P1 * *
      **
      ** P1 elements are popped off of the top of stack and discarded.
      */

      ** top of the stack.
      */
      case OP_Dup: {
        int i = p->tos - pOp->p1;
        int j = ++p->tos;
        if( i<0 ) goto not_enough_stack;
        if( NeedStack(p, p->tos) ) goto no_mem;
        p->aStack[j] = p->aStack[i];
        if( p->aStack[i].flags & STK_Dyn ){
          p->zStack[j] = sqliteMalloc( p->aStack[j].n );
          if( p->zStack[j]==0 ) goto no_mem;
          memcpy(p->zStack[j], p->zStack[i], p->aStack[j].n);
        }else{
          p->zStack[j] = p->zStack[i];
        }
        break;
      }

      /* Opcode: Pull P1 * *
      **
      ** The P1-th element is removed from its current location on 
      ** the stack and pushed back on top of the stack.  The
      ** top of the stack is element 0, so "Pull 0 0 0" is
      ** a no-op.
      */
      case OP_Pull: {
        int from = p->tos - pOp->p1;
        int to = p->tos;
        int i;
        Stack ts;
        char *tz;
        if( from<0 ) goto not_enough_stack;
        ts = p->aStack[from];
        tz = p->zStack[from];
        for(i=from; i<to; i++){
          p->aStack[i] = p->aStack[i+1];
          p->zStack[i] = p->zStack[i+1];
        }
        p->aStack[to] = ts;
        p->zStack[to] = tz;
        break;
      }

      /* Opcode: ColumnCount P1 * *
      **
      ** Specify the number of column values that will appear in the

      */
      case OP_Callback: {
        int i = p->tos - pOp->p1 + 1;
        int j;
        if( i<0 ) goto not_enough_stack;
        if( NeedStack(p, p->tos+2) ) goto no_mem;
        for(j=i; j<=p->tos; j++){
          if( (p->aStack[j].flags & STK_Null)==0 ){
            if( Stringify(p, j) ) goto no_mem;
          }
        }
        p->zStack[p->tos+1] = 0;
        if( xCallback!=0 ){
          if( xCallback(pArg, pOp->p1, &p->zStack[i], p->azColName)!=0 ){
            rc = SQLITE_ABORT;
          }
        }
        PopStack(p, pOp->p1);
        break;
      }

      /* Opcode: Concat P1 P2 P3
      **
      ** Look at the first P1 elements of the stack.  Append them all 
      ** together with the lowest element first.  Use P3 as a separator.  
      ** Put the result on the top of the stack.  The original P1 elements
      ** are popped from the stack if P2==0 and retained if P2==1.
      **
      ** If P3 is NULL, then use no separator.  When P1==1, this routine
      ** makes a copy of the top stack element into memory obtained
      ** from sqliteMalloc().
      */
      case OP_Concat: {
        char *zNew;
        int nByte;
        int nField;
        int i, j;
        char *zSep;
        int nSep;

        nField = pOp->p1;
        zSep = pOp->p3;
        if( zSep==0 ) zSep = "";
        nSep = strlen(zSep);
        if( p->tos+1<nField ) goto not_enough_stack;
        nByte = 1 - nSep;
        for(i=p->tos-nField+1; i<=p->tos; i++){
          if( p->aStack[i].flags & STK_Null ){
            nByte += nSep;
          }else{
            if( Stringify(p, i) ) goto no_mem;
            nByte += p->aStack[i].n - 1 + nSep;
          }
        }
        zNew = sqliteMalloc( nByte );
        if( zNew==0 ) goto no_mem;
        j = 0;
        for(i=p->tos-nField+1; i<=p->tos; i++){
          if( (p->aStack[i].flags & STK_Null)==0 ){
            memcpy(&zNew[j], p->zStack[i], p->aStack[i].n-1);
            j += p->aStack[i].n-1;
          }
          if( nSep>0 && i<p->tos ){
            memcpy(&zNew[j], zSep, nSep);
            j += nSep;
          }
        }
        zNew[j] = 0;
        if( pOp->p2==0 ) PopStack(p, nField);
        NeedStack(p, p->tos+1);
        p->tos++;
        p->aStack[p->tos].n = nByte;
        p->aStack[p->tos].flags = STK_Str|STK_Dyn;
        p->zStack[p->tos] = zNew;

        break;
      }

      /* Opcode: Add * * *
      **
      ** Pop the top two elements from the stack, add them together,
      ** and push the result back onto the stack.  If either element

      case OP_Add:
      case OP_Subtract:
      case OP_Multiply:
      case OP_Divide: {
        int tos = p->tos;
        int nos = tos - 1;
        if( nos<0 ) goto not_enough_stack;
        if( (p->aStack[tos].flags & p->aStack[nos].flags & STK_Int)==STK_Int ){
          int a, b;
          a = p->aStack[tos].i;
          b = p->aStack[nos].i;
          switch( pOp->opcode ){
            case OP_Add:         b += a;       break;
            case OP_Subtract:    b -= a;       break;
            case OP_Multiply:    b *= a;       break;
            default: {
              if( a==0 ){ 
                sqliteSetString(pzErrMsg, "division by zero", 0);
                rc = SQLITE_ERROR;
                goto cleanup;
              }
              b /= a;
              break;
            }
          }
          PopStack(p, 2);
          p->tos = nos;
          p->aStack[nos].i = b;
          p->aStack[nos].flags = STK_Int;
        }else{
          double a, b;
          Realify(p, tos);
          Realify(p, nos);
          a = p->aStack[tos].r;
          b = p->aStack[nos].r;
          switch( pOp->opcode ){
            case OP_Add:         b += a;       break;
            case OP_Subtract:    b -= a;       break;
            case OP_Multiply:    b *= a;       break;
            default: {
              if( a==0.0 ){ 
                sqliteSetString(pzErrMsg, "division by zero", 0);
                rc = SQLITE_ERROR;
                goto cleanup;
              }
              b /= a;
              break;
            }
          }

          PopStack(p, 1);
          Release(p, nos);
          p->aStack[nos].r = b;
          p->aStack[nos].flags = STK_Real;
        }
        break;
      }

      /* Opcode: Max * * *
      **
      ** Pop the top two elements from the stack then push back the
      ** largest of the two.
      */
      case OP_Max: {
        int tos = p->tos;
        int nos = tos - 1;
        int ft, fn;
        int copy = 0;
        if( nos<0 ) goto not_enough_stack;
        ft = p->aStack[tos].flags;
        fn = p->aStack[nos].flags;
        if( fn & STK_Null ){
          copy = 1;
        }else if( (ft & fn & STK_Int)==STK_Int ){
          copy = p->aStack[nos].i<p->aStack[tos].i;

        }else if( ( (ft|fn) & (STK_Int|STK_Real) ) !=0 ){
          Realify(p, tos);
          Realify(p, nos);
          copy = p->aStack[tos].r>p->aStack[nos].r;
        }else{
          Stringify(p, tos);
          Stringify(p, nos);
          copy = sqliteCompare(p->zStack[tos],p->zStack[nos])>0;
        }
        if( copy ){
          Release(p, nos);
          p->aStack[nos] = p->aStack[tos];
          p->zStack[nos] = p->zStack[tos];

          p->zStack[tos] = 0;
          p->aStack[tos].flags = 0;
        }else{
          Release(p, tos);
        }
        p->tos = nos;
        break;
      }

      /* Opcode: Min * * *
      **
      ** Pop the top two elements from the stack then push back the
      ** smaller of the two. 
      **
      ** If P1==1, always choose TOS for the min and decrement P1.
      ** This is self-altering code...
      */
      case OP_Min: {
        int tos = p->tos;
        int nos = tos - 1;
        int ft, fn;
        int copy = 0;
        if( nos<0 ) goto not_enough_stack;
        ft = p->aStack[tos].flags;
        fn = p->aStack[nos].flags;
        if( pOp->p1 ){
          copy = 1;
          pOp->p1 = 0;
        }else if( fn & STK_Null ){
          copy = 1;
        }else if( (ft & fn & STK_Int)==STK_Int ){
          copy = p->aStack[nos].i>p->aStack[tos].i;

        }else if( ( (ft|fn) & (STK_Int|STK_Real) ) !=0 ){
          Realify(p, tos);
          Realify(p, nos);
          copy = p->aStack[tos].r<p->aStack[nos].r;
        }else{
          Stringify(p, tos);
          Stringify(p, nos);
          copy = sqliteCompare(p->zStack[tos],p->zStack[nos])<0;
        }
        if( copy ){
          Release(p, nos);
          p->aStack[nos] = p->aStack[tos];
          p->zStack[nos] = p->zStack[tos];

          p->zStack[tos] = 0;





          p->aStack[tos].flags = 0;
        }else{
          Release(p, tos);
        }
        p->tos = nos;
        break;
      }

      /* Opcode: AddImm  P1 * *
      ** 
      ** Add the value P1 to whatever is on top of the stack.
      */
      case OP_AddImm: {
        int tos = p->tos;
        if( tos<0 ) goto not_enough_stack;
        Integerify(p, tos);
        p->aStack[tos].i += pOp->p1;
        break;
      }

      /* Opcode: Eq * P2 *
      **
      ** Pop the top two elements from the stack.  If they are equal, then
      ** jump to instruction P2.  Otherwise, continue to the next instruction.

      case OP_Lt:
      case OP_Le:
      case OP_Gt:
      case OP_Ge: {
        int tos = p->tos;
        int nos = tos - 1;
        int c;
        int ft, fn;
        if( nos<0 ) goto not_enough_stack;


        ft = p->aStack[tos].flags;
        fn = p->aStack[nos].flags;

        if( (ft & fn)==STK_Int ){
          c = p->aStack[nos].i - p->aStack[tos].i;






        }else{
          Stringify(p, tos);
          Stringify(p, nos);
          c = sqliteCompare(p->zStack[nos], p->zStack[tos]);
        }
        switch( pOp->opcode ){
          case OP_Eq:    c = c==0;     break;
          case OP_Ne:    c = c!=0;     break;
          case OP_Lt:    c = c<0;      break;
          case OP_Le:    c = c<=0;     break;
          case OP_Gt:    c = c>0;      break;
          default:       c = c>=0;     break;

        }
        PopStack(p, 2);
        if( c ) pc = pOp->p2-1;
        break;
      }

      /* Opcode: Like P1 P2 *

        break;
      }

      /* Opcode: And * * *
      **
      ** Pop two values off the stack.  Take the logical AND of the
      ** two values and push the resulting boolean value back onto the
      ** stack. 


      */
      /* Opcode: Or * * *
      **
      ** Pop two values off the stack.  Take the logical OR of the
      ** two values and push the resulting boolean value back onto the
      ** stack. 


      */
      case OP_And:
      case OP_Or: {
        int tos = p->tos;
        int nos = tos - 1;
        int c;
        if( nos<0 ) goto not_enough_stack;
        Integerify(p, tos);
        Integerify(p, nos);
        if( pOp->opcode==OP_And ){
          c = p->aStack[tos].i && p->aStack[nos].i;
        }else{
          c = p->aStack[tos].i || p->aStack[nos].i;
        }
        PopStack(p, 2);
        p->tos++;
        p->aStack[nos].i = c;
        p->aStack[nos].flags = STK_Int;
        break;
      }

      /* Opcode: Negative * * *
      **
      ** Treat the top of the stack as a numeric quantity.  Replace it
      ** with its additive inverse.

      */
      case OP_Negative: {
        int tos;
        if( (tos = p->tos)<0 ) goto not_enough_stack;
        if( p->aStack[tos].flags & STK_Real ){
          Release(p, tos);
          p->aStack[tos].r = -p->aStack[tos].r;
          p->aStack[tos].flags = STK_Real;
        }else if( p->aStack[tos].flags & STK_Int ){
          Release(p, tos);
          p->aStack[tos].i = -p->aStack[tos].i;
          p->aStack[tos].flags = STK_Int;
        }else{
          Realify(p, tos);
          Release(p, tos);
          p->aStack[tos].r = -p->aStack[tos].r;
          p->aStack[tos].flags = STK_Real;
        }
        break;
      }

      /* Opcode: Not * * *
      **
      ** Treat the top of the stack as a boolean value.  Replace it
      ** with its complement.

      */
      case OP_Not: {
        int tos = p->tos;
        if( p->tos<0 ) goto not_enough_stack;

        Integerify(p, tos);
        Release(p, tos);
        p->aStack[tos].i = !p->aStack[tos].i;
        p->aStack[tos].flags = STK_Int;
        break;
      }

      /* Opcode: Noop * * *
      **
      ** Do nothing.  This instruction is often useful as a jump
      ** destination.

      ** true, then jump to p2.  Otherwise continue to the next instruction.
      ** An integer is false if zero and true otherwise.  A string is
      ** false if it has zero length and true otherwise.
      */
      case OP_If: {
        int c;
        if( p->tos<0 ) goto not_enough_stack;
        Integerify(p, p->tos);
        c = p->aStack[p->tos].i;
        PopStack(p, 1);
        if( c ) pc = pOp->p2-1;
        break;
      }

      /* Opcode: IsNull * P2 *
      **
      ** Pop a single value from the stack.  If the value popped is NULL
      ** then jump to p2.  Otherwise continue to the next 
      ** instruction.
      */
      case OP_IsNull: {
        int c;
        if( p->tos<0 ) goto not_enough_stack;
        c = (p->aStack[p->tos].flags & STK_Null)!=0;
        PopStack(p, 1);
        if( c ) pc = pOp->p2-1;
        break;
      }

      /* Opcode: NotNull * P2 *
      **
      ** Pop a single value from the stack.  If the value popped is not an
      ** empty string, then jump to p2.  Otherwise continue to the next 
      ** instruction.
      */
      case OP_NotNull: {
        int c;
        if( p->tos<0 ) goto not_enough_stack;
        c = (p->aStack[p->tos].flags & STK_Null)==0;
        PopStack(p, 1);
        if( c ) pc = pOp->p2-1;
        break;
      }

      /* Opcode: MakeRecord P1 * *
      **
      ** Convert the top P1 entries of the stack into a single entry
      ** suitable for use as a data record in the database.  To do this
      ** all entries (except NULLs) are converted to strings and 
      ** concatenated.  The null-terminators are preserved by the concatation
      ** and serve as a boundry marker between fields.  The lowest entry
      ** on the stack is the first in the concatenation and the top of
      ** the stack is the last.  After all fields are concatenated, an
      ** index header is added.  The index header consists of P1 integers
      ** which hold the offset of the beginning of each field from the
      ** beginning of the completed record including the header.  The
      ** index for NULL entries is 0.
      */
      case OP_MakeRecord: {
        char *zNewRecord;
        int nByte;
        int nField;
        int i, j;
        int addr;

        nField = pOp->p1;
        if( p->tos+1<nField ) goto not_enough_stack;
        nByte = 0;
        for(i=p->tos-nField+1; i<=p->tos; i++){
          if( (p->aStack[i].flags & STK_Null)==0 ){
            if( Stringify(p, i) ) goto no_mem;
            nByte += p->aStack[i].n;
          }
        }
        nByte += sizeof(int)*nField;
        zNewRecord = sqliteMalloc( nByte );
        if( zNewRecord==0 ) goto no_mem;
        j = 0;
        addr = sizeof(int)*nField;
        for(i=p->tos-nField+1; i<=p->tos; i++){
          if( p->aStack[i].flags & STK_Null ){
            int zero = 0;
            memcpy(&zNewRecord[j], (char*)&zero, sizeof(int));
          }else{
            memcpy(&zNewRecord[j], (char*)&addr, sizeof(int));
            addr += p->aStack[i].n;

          }

          j += sizeof(int);
        }
        for(i=p->tos-nField+1; i<=p->tos; i++){
          if( (p->aStack[i].flags & STK_Null)==0 ){
            memcpy(&zNewRecord[j], p->zStack[i], p->aStack[i].n);
            j += p->aStack[i].n;
          }
        }
        PopStack(p, nField);
        NeedStack(p, p->tos+1);
        p->tos++;
        p->aStack[p->tos].n = nByte;
        p->aStack[p->tos].flags = STK_Str | STK_Dyn;
        p->zStack[p->tos] = zNewRecord;
        break;
      }

      /* Opcode: MakeKey P1 P2 *
      **
      ** Convert the top P1 entries of the stack into a single entry suitable

        int nField;
        int i, j;

        nField = pOp->p1;
        if( p->tos+1<nField ) goto not_enough_stack;
        nByte = 0;
        for(i=p->tos-nField+1; i<=p->tos; i++){
          if( p->aStack[i].flags & STK_Null ){
            nByte++;
          }else{
            if( Stringify(p, i) ) goto no_mem;
            nByte += p->aStack[i].n;
          }
        }
        zNewKey = sqliteMalloc( nByte );
        if( zNewKey==0 ) goto no_mem;
        j = 0;
        for(i=p->tos-nField+1; i<=p->tos; i++){
          if( (p->aStack[i].flags & STK_Null)==0 ){
            memcpy(&zNewKey[j], p->zStack[i], p->aStack[i].n-1);
            j += p->aStack[i].n-1;
          }
          if( i<p->tos ) zNewKey[j++] = '\t';
        }
        zNewKey[j] = 0;
        if( pOp->p2==0 ) PopStack(p, nField);
        NeedStack(p, p->tos+1);
        p->tos++;
        p->aStack[p->tos].n = nByte;
        p->aStack[p->tos].flags = STK_Str|STK_Dyn;
        p->zStack[p->tos] = zNewKey;
        break;
      }

      /* Opcode: Open P1 P2 P3
      **
      ** Open a new database table named P3.  Give it an identifier P1.
      ** Open readonly if P2==0 and for reading and writing if P2!=0.
      ** The table is created if it does not already exist and P2!=0.
      ** If there is already another table opened on P1, then the old
      ** table is closed first.  All tables are automatically closed when
      ** the VDBE finishes execution.  The P1 values need not be
      ** contiguous but all P1 values should be small integers.  It is
      ** an error for P1 to be negative.
      **
      ** If P3 is null or an empty string, a temporary table is opened.
      */
      case OP_Open: {
        int i = pOp->p1;
        if( i<0 ) goto bad_instruction;
        if( i>=p->nTable ){
          int j;
          p->aTab = sqliteRealloc( p->aTab, (i+1)*sizeof(VdbeTable) );

      ** stack or anything like that.
      */
      case OP_Fetch: {
        int i = pOp->p1;
        int tos = p->tos;
        if( tos<0 ) goto not_enough_stack;
        if( i>=0 && i<p->nTable && p->aTab[i].pTable ){
          if( p->aStack[tos].flags & STK_Int ){
            sqliteDbbeFetch(p->aTab[i].pTable, sizeof(int), 
                           (char*)&p->aStack[tos].i);
          }else{
            if( Stringify(p, tos) ) goto no_mem;
            sqliteDbbeFetch(p->aTab[i].pTable, p->aStack[tos].n, 
                           p->zStack[tos]);
          }
        }
        PopStack(p, 1);
        break;
      }

      /* Opcode: Distinct P1 P2 *
      **
      ** Use the top of the stack as a key.  If a record with that key
      ** does not exist in table P1, then jump to P2.  If the record
      ** does already exist, then fall thru.  The record is not retrieved.
      ** The key is not popped from the stack.
      */
      case OP_Distinct: {
        int i = pOp->p1;
        int tos = p->tos;
        int alreadyExists = 0;
        if( tos<0 ) goto not_enough_stack;
        if( i>=0 && i<p->nTable && p->aTab[i].pTable ){
          if( p->aStack[tos].flags & STK_Int ){
            alreadyExists = sqliteDbbeTest(p->aTab[i].pTable, sizeof(int), 
                                          (char*)&p->aStack[tos].i);
          }else{
            if( Stringify(p, tos) ) goto no_mem;
            alreadyExists = sqliteDbbeTest(p->aTab[i].pTable, p->aStack[tos].n, 
                                           p->zStack[tos]);
          }
        }
        if( !alreadyExists ){
          pc = pOp->p2 - 1;
        }
        break;

        if( i<0 || i>=p->nTable || p->aTab[i].pTable==0 ){
          v = 0;
        }else{
          v = sqliteDbbeNew(p->aTab[i].pTable);
        }
        NeedStack(p, p->tos+1);
        p->tos++;
        p->aStack[p->tos].i = v;
        p->aStack[p->tos].flags = STK_Int;
        break;
      }

      /* Opcode: Put P1 * *
      **
      ** Write an entry into the database table P1.  A new entry is
      ** created if it doesn't already exist, or the data for an existing
      ** entry is overwritten.  The data is the value on the top of the
      ** stack.  The key is the next value down on the stack.  The stack
      ** is popped twice by this instruction.
      */
      case OP_Put: {
        int tos = p->tos;
        int nos = p->tos-1;
        int i = pOp->p1;
        if( nos<0 ) goto not_enough_stack;
        if( i>=0 && i<p->nTable && p->aTab[i].pTable!=0 ){
          char *zKey;
          int nKey;
          if( (p->aStack[nos].flags & STK_Int)==0 ){
            if( Stringify(p, nos) ) goto no_mem;

            nKey = p->aStack[nos].n;
            zKey = p->zStack[nos];
          }else{
            nKey = sizeof(int);
            zKey = (char*)&p->aStack[nos].i;
          }
          sqliteDbbePut(p->aTab[i].pTable, nKey, zKey,
                        p->aStack[tos].n, p->zStack[tos]);
        }
        PopStack(p, 2);
        break;
      }

      /* Opcode: Delete P1 * *
      **
      ** The top of the stack is a key.  Remove this key and its data
      ** from database table P1.  Then pop the stack to discard the key.
      */
      case OP_Delete: {
        int tos = p->tos;
        int i = pOp->p1;
        if( tos<0 ) goto not_enough_stack;
        if( i>=0 && i<p->nTable && p->aTab[i].pTable!=0 ){
          char *zKey;
          int nKey;
          if( (p->aStack[tos].flags & STK_Int)==0 ){
            if( Stringify(p, tos) ) goto no_mem;
            nKey = p->aStack[tos].n;
            zKey = p->zStack[tos];
          }else{
            nKey = sizeof(int);
            zKey = (char*)&p->aStack[tos].n;
          }
          sqliteDbbeDelete(p->aTab[i].pTable, nKey, zKey);
        }
        PopStack(p, 1);
        break;
      }

      /* Opcode: Field P1 P2 *
      **
      ** Push onto the stack the value of the P2-th field from the
      ** most recent Fetch from table P1.
      ** 
      ** The value pushed is just a pointer to the data in the cursor.
      ** The value will go away the next time a record is fetched from P1,
      ** or when P1 is closed.  Make a copy of the string if it needs
      ** to persist longer than that.
      */
      case OP_Field: {
        int *pAddr;
        int amt;
        int i = pOp->p1;
        int p2 = pOp->p2;
        int tos = ++p->tos;
        DbbeTable *pTab;
        char *z;

        if( NeedStack(p, tos) ) goto no_mem;
        if( i>=0 && i<p->nTable && (pTab = p->aTab[i].pTable)!=0 ){
          amt = sqliteDbbeDataLength(pTab);
          if( amt<=sizeof(int)*(p2+1) ){
            p->aStack[tos].flags = STK_Null;
            break;
          }
          pAddr = (int*)sqliteDbbeReadData(pTab, sizeof(int)*p2);
          if( *pAddr==0 ){
            p->aStack[tos].flags = STK_Null;
            break;
          }
          p->zStack[tos] = z = sqliteDbbeReadData(pTab, *pAddr);
          p->aStack[tos].n = strlen(z) + 1;
          p->aStack[tos].flags = STK_Str;
        }
        break;
      }

      /* Opcode: Key P1 * *
      **
      ** Push onto the stack an integer which is the first 4 bytes of the
      ** the key to the current entry in a sequential scan of the table P1.
      ** A sequential scan is started using the Next opcode.
      */
      case OP_Key: {
        int i = pOp->p1;
        int tos = ++p->tos;
        DbbeTable *pTab;

        if( NeedStack(p, p->tos) ) goto no_mem;
        if( i>=0 && i<p->nTable && (pTab = p->aTab[i].pTable)!=0 ){
          char *z = sqliteDbbeReadKey(pTab, 0);
          memcpy(&p->aStack[tos].i, z, sizeof(int));
          p->aStack[tos].flags = STK_Int;
        }
        break;
      }

      /* Opcode: Rewind P1 * *
      **
      ** The next use of the Key or Field or Next instruction for P1 

          int *aIdx;
          int nIdx;
          int j;
          nIdx = sqliteDbbeDataLength(pTab)/sizeof(int);
          aIdx = (int*)sqliteDbbeReadData(pTab, 0);
          for(j=p->aTab[i].index; j<nIdx; j++){
            if( aIdx[j]!=0 ){
              p->aStack[tos].i = aIdx[j];
              p->aStack[tos].flags = STK_Int;
              break;
            }
          }
          if( j>=nIdx ){
            j = -1;
            pc = pOp->p2 - 1;
            PopStack(p, 1);

        int i = pOp->p1;
        int tos = p->tos;
        int nos = tos - 1;
        DbbeTable *pTab;
        if( nos<0 ) goto not_enough_stack;
        if( i>=0 && i<p->nTable && (pTab = p->aTab[i].pTable)!=0 ){
          int r;
          int newVal;
          Integerify(p, nos);
          newVal = p->aStack[nos].i;
          if( Stringify(p, tos) ) goto no_mem;
          r = sqliteDbbeFetch(pTab, p->aStack[tos].n, p->zStack[tos]);
          if( r==0 ){
            /* Create a new record for this index */
            sqliteDbbePut(pTab, p->aStack[tos].n, p->zStack[tos],
                          sizeof(int), (char*)&newVal);
          }else{
            /* Extend the existing record */
            int nIdx;
            int *aIdx;
            nIdx = sqliteDbbeDataLength(pTab)/sizeof(int);
            aIdx = sqliteMalloc( sizeof(int)*(nIdx+1) );
            if( aIdx==0 ) goto no_mem;
            sqliteDbbeCopyData(pTab, 0, nIdx*sizeof(int), (char*)aIdx);
            aIdx[nIdx] = newVal;
            sqliteDbbePut(pTab, p->aStack[tos].n, p->zStack[tos],
                          sizeof(int)*(nIdx+1), (char*)aIdx);
            sqliteFree(aIdx);
          }
        }
        PopStack(p, 2);
        break;
      }

        DbbeTable *pTab;
        if( nos<0 ) goto not_enough_stack;
        if( i>=0 && i<p->nTable && (pTab = p->aTab[i].pTable)!=0 ){
          int *aIdx;
          int nIdx;
          int j;
          int r;
          int oldVal;
          Integerify(p, nos);
          oldVal = p->aStack[nos].i;
          if( Stringify(p, tos) ) goto no_mem;
          r = sqliteDbbeFetch(pTab, p->aStack[tos].n, p->zStack[tos]);
          if( r==0 ) break;
          nIdx = sqliteDbbeDataLength(pTab)/sizeof(int);
          aIdx = (int*)sqliteDbbeReadData(pTab, 0);
          for(j=0; j<nIdx && aIdx[j]!=oldVal; j++){}
          if( j>=nIdx ) break;
          aIdx[j] = aIdx[nIdx-1];
          if( nIdx==1 ){
            sqliteDbbeDelete(pTab, p->aStack[tos].n, p->zStack[tos]);
          }else{
            sqliteDbbePut(pTab, p->aStack[tos].n, p->zStack[tos], 
                          sizeof(int)*(nIdx-1), (char*)aIdx);
          }
        }
        PopStack(p, 2);
        break;
      }

      ** into the temporary storage file P1.
      */
      case OP_ListWrite: {
        int i = pOp->p1;
        if( i<0 ) goto bad_instruction;
        if( p->tos<0 ) goto not_enough_stack;
        if( i<p->nList && p->apList[i]!=0 ){
          int val;
          Integerify(p, p->tos);
          val = p->aStack[p->tos].i;
          PopStack(p, 1);
          fwrite(&val, sizeof(int), 1, p->apList[i]);
        }
        break;
      }

      /* Opcode: ListRewind P1 * *

        int i = pOp->p1;
        int val, amt;
        if( i<0 || i>=p->nList || p->apList[i]==0 ) goto bad_instruction;
        amt = fread(&val, sizeof(int), 1, p->apList[i]);
        if( amt==1 ){
          p->tos++;
          if( NeedStack(p, p->tos) ) goto no_mem;
          p->aStack[p->tos].n = val;
          p->aStack[p->tos].flags = STK_Int;
        }else{
          pc = pOp->p2 - 1;
        }
        break;
      }

      /* Opcode: ListClose P1 * *

      /* Opcode: SortPut P1 * *
      **
      ** The TOS is the key and the NOS is the data.  Pop both from the stack
      ** and put them on the sorter.
      */
      case OP_SortPut: {
        int i = pOp->p1;
        int tos = p->tos;
        int nos = tos - 1;
        Sorter *pSorter;
        if( i<0 || i>=p->nSort ) goto bad_instruction;
        if( tos<1 ) goto not_enough_stack;
        if( Stringify(p, tos) || Stringify(p, nos) ) goto no_mem;

        pSorter = sqliteMalloc( sizeof(Sorter) );
        if( pSorter==0 ) goto no_mem;
        pSorter->pNext = p->apSort[i];
        p->apSort[i] = pSorter;
        pSorter->nKey = p->aStack[tos].n;
        pSorter->zKey = p->zStack[tos];
        pSorter->nData = p->aStack[nos].n;
        pSorter->pData = p->zStack[nos];
        p->aStack[tos].flags = 0;
        p->aStack[nos].flags = 0;
        p->zStack[tos] = 0;
        p->zStack[nos] = 0;
        p->tos -= 2;
        break;
      }

      /* Opcode: SortMakeRec P1 * *
      **
      ** The top P1 elements are the arguments to a callback.  Form these
      ** elements into a single data entry that can be stored on a sorter
      ** using SortPut and later fed to a callback using SortCallback.
      */
      case OP_SortMakeRec: {
        char *z;
        char **azArg;
        int nByte;
        int nField;
        int i, j;

        nField = pOp->p1;
        if( p->tos+1<nField ) goto not_enough_stack;
        nByte = 0;
        for(i=p->tos-nField+1; i<=p->tos; i++){
          if( (p->aStack[i].flags & STK_Null)==0 ){
            if( Stringify(p, i) ) goto no_mem;
            nByte += p->aStack[i].n;
          }
        }
        nByte += sizeof(char*)*(nField+1);
        azArg = sqliteMalloc( nByte );
        if( azArg==0 ) goto no_mem;
        z = (char*)&azArg[nField+1];
        for(j=0, i=p->tos-nField+1; i<=p->tos; i++, j++){
          if( p->aStack[i].flags & STK_Null ){
            azArg[j] = 0;
          }else{
            azArg[j] = z;
            strcpy(z, p->zStack[i]);
            z += p->aStack[i].n;
          }
        }
        PopStack(p, nField);
        NeedStack(p, p->tos+1);
        p->tos++;
        p->aStack[p->tos].n = nByte;
        p->zStack[p->tos] = (char*)azArg;
        p->aStack[p->tos].flags = STK_Str|STK_Dyn;
        break;
      }

      /* Opcode: SortMakeKey P1 * P3
      **
      ** Convert the top few entries of the stack into a sort key.  The
      ** number of stack entries consumed is the number of characters in 

        int i, j, k;

        nField = strlen(pOp->p3);
        if( p->tos+1<nField ) goto not_enough_stack;
        nByte = 1;
        for(i=p->tos-nField+1; i<=p->tos; i++){
          if( Stringify(p, i) ) goto no_mem;
          nByte += p->aStack[i].n+2;
        }
        zNewKey = sqliteMalloc( nByte );
        if( zNewKey==0 ) goto no_mem;
        j = 0;
        k = nField-1;
        for(i=p->tos-nField+1; i<=p->tos; i++){
          zNewKey[j++] = pOp->p3[k--];
          memcpy(&zNewKey[j], p->zStack[i], p->aStack[i].n-1);
          j += p->aStack[i].n-1;
          zNewKey[j++] = 0;
        }
        zNewKey[j] = 0;
        PopStack(p, nField);
        NeedStack(p, p->tos+1);
        p->tos++;
        p->aStack[p->tos].n = nByte;
        p->aStack[p->tos].flags = STK_Str|STK_Dyn;
        p->zStack[p->tos] = zNewKey;
        break;
      }

      /* Opcode: Sort P1 * *
      **
      ** Sort all elements on the given sorter.  The algorithm is a

        if( i<0 ) goto bad_instruction;
        if( i<p->nSort && p->apSort[i]!=0 ){
          Sorter *pSorter = p->apSort[i];
          p->apSort[i] = pSorter->pNext;
          p->tos++;
          NeedStack(p, p->tos);
          p->zStack[p->tos] = pSorter->pData;
          p->aStack[p->tos].n = pSorter->nData;
          p->aStack[p->tos].flags = STK_Str|STK_Dyn;
          sqliteFree(pSorter->zKey);
          sqliteFree(pSorter);
        }else{
          pc = pOp->p2 - 1;
        }
        break;
      }

        int i = pOp->p1;
        if( i<0 ) goto bad_instruction;
        if( i<p->nSort && p->apSort[i]!=0 ){
          Sorter *pSorter = p->apSort[i];
          p->tos++;
          NeedStack(p, p->tos);
          sqliteSetString(&p->zStack[p->tos], pSorter->zKey, 0);
          p->aStack[p->tos].n = pSorter->nKey;
          p->aStack[p->tos].flags = STK_Str|STK_Dyn;
        }
        break;
      }

      /* Opcode: SortCallback P1 P2 *
      **
      ** The top of the stack contains a callback record built using

        if( i>=0 && i<p->nField && p->azField ){
          z = p->azField[i];
        }else{
          z = 0;
        }
        if( z==0 ) z = "";
        p->tos++;
        p->aStack[p->tos].n = strlen(z) + 1;
        p->zStack[p->tos] = z;
        p->aStack[p->tos].flags = STK_Str;
        break;
      }

      /* An other opcode is illegal...
      */
      default: {
        sprintf(zBuf,"%d",pOp->opcode);
        sqliteSetString(pzErrMsg, "unknown opcode ", zBuf, 0);
        rc = SQLITE_INTERNAL;
        break;
      }
    }
    if( pc<-1 || pc>=p->nOp ){
      sqliteSetString(pzErrMsg, "jump destination out of range", 0);
      rc = SQLITE_INTERNAL;
    }
    if( p->trace && p->tos>=0 ){
      int i;
      fprintf(p->trace, "Stack:");
      for(i=p->tos; i>=0 && i>p->tos-5; i--){
        if( p->aStack[i].flags & STK_Null ){
          fprintf(p->trace, " NULL");
        }else if( p->aStack[i].flags & STK_Int ){
          fprintf(p->trace, " i:%d", p->aStack[i].i);
        }else if( p->aStack[i].flags & STK_Real ){
          fprintf(p->trace, " r:%g", p->aStack[i].r);
        }else if( p->aStack[i].flags & STK_Str ){
          if( p->aStack[i].flags & STK_Dyn ){
            fprintf(p->trace, " z:[%.11s]", p->zStack[i]);
          }else{
            fprintf(p->trace, " s:[%.11s]", p->zStack[i]);
          }
        }else{
          fprintf(p->trace, " ???");
        }
      }
      fprintf(p->trace,"\n");
    }
  }

cleanup:

*************************************************************************
** 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 1.5 2000/06/04 12:58:39 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_ColumnCount        41
#define OP_ColumnName         42
#define OP_Callback           43

#define OP_Integer            44
#define OP_String             45
#define OP_Null               46
#define OP_Pop                47
#define OP_Dup                48
#define OP_Pull               49

#define OP_Add                50
#define OP_AddImm             51
#define OP_Subtract           52
#define OP_Multiply           53
#define OP_Divide             54
#define OP_Min                55
#define OP_Max                56
#define OP_Like               57
#define OP_Glob               58
#define OP_Eq                 59
#define OP_Ne                 60
#define OP_Lt                 61
#define OP_Le                 62
#define OP_Gt                 63
#define OP_Ge                 64
#define OP_IsNull             65
#define OP_NotNull            66
#define OP_Negative           67
#define OP_And                68
#define OP_Or                 69
#define OP_Not                70
#define OP_Concat             71
#define OP_Noop               72

#define OP_MAX                72

/*
** Prototypes for the VDBE interface.  See comments on the implementation
** for a description of what each of these routines does.
*/
Vdbe *sqliteVdbeCreate(Dbbe*);
int sqliteVdbeAddOp(Vdbe*,int,int,int,const char*,int);