SQLite

** 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 1.73 2004/06/19 15:40:23 drh Exp $
*/
#include <ctype.h>
#include <math.h>
#include <stdlib.h>
#include <assert.h>
#include "sqliteInt.h"
#include "vdbeInt.h"

** to the comment for compileLike() function for details.
*/
struct LikePattern {
  int nState;
  struct LikeState {
    int val;           /* Unicode codepoint or -1 for any char i.e. '_' */
    int failstate;     /* State to jump to if next char is not val */
  } aState[1];
};
typedef struct LikePattern LikePattern;

void deleteLike(void *pLike){
  sqliteFree(pLike);
}

      if( pFunc && aAggs[i].needCollSeq ){
        pFunc->needCollSeq = 1;
      }
    }
  }
  sqlite3RegisterDateTimeFunctions(db);
}

**
** Various scripts scan this source file in order to generate HTML
** documentation, headers files, or other derived files.  The formatting
** of the code in this file is, therefore, important.  See other comments
** in this file for details.  If in doubt, do not deviate from existing
** commenting and indentation practices when changing or adding code.
**
** $Id: vdbe.c,v 1.381 2004/06/19 15:40:23 drh Exp $
*/
#include "sqliteInt.h"
#include "os.h"
#include <ctype.h>
#include "vdbeInt.h"

/*

  if( sqlite3SafetyOn(db) ) goto abort_due_to_misuse;
  popStack(&pTos, n);

  /* If any auxilary data functions have been called by this user function,
  ** immediately call the destructor for any non-static values.
  */
  if( ctx.pVdbeFunc ){

    sqlite3VdbeDeleteAuxData(ctx.pVdbeFunc, pOp->p2);








    pOp->p3 = (char *)ctx.pVdbeFunc;
    pOp->p3type = P3_VDBEFUNC;
  }

  /* Copy the result of the function to the top of the stack */
  pTos++;
  *pTos = ctx.s;

#if !defined(NDEBUG) || defined(VDBE_PROFILE)
void sqlite3VdbePrintOp(FILE*, int, Op*);
#endif
int sqlite3VdbeSerialTypeLen(u32);
u32 sqlite3VdbeSerialType(Mem*);
int sqlite3VdbeSerialPut(unsigned char*, Mem*);
int sqlite3VdbeSerialGet(const unsigned char*, u32, Mem*);
void sqlite3VdbeDeleteAuxData(VdbeFunc*, int);

int sqlite2BtreeKeyCompare(BtCursor *, const void *, int, int, int *);
int sqlite3VdbeIdxKeyCompare(Cursor*, int , const unsigned char*, int*);
int sqlite3VdbeIdxRowid(BtCursor *, i64 *);
int sqlite3MemCompare(const Mem*, const Mem*, const CollSeq*);
int sqlite3VdbeRecordCompare(void*,int,const void*,int, const void*);
int sqlite3VdbeIdxRowidLen(int,const u8*);

** the user-function defined by pCtx.
*/
void *sqlite3_get_auxdata(sqlite3_context *pCtx, int iArg){
  VdbeFunc *pVdbeFunc = pCtx->pVdbeFunc;
  if( !pVdbeFunc || iArg>=pVdbeFunc->nAux || iArg<0 ){
    return 0;
  }
  return pVdbeFunc->apAux[iArg].pAux;
}

/*
** Set the auxilary data pointer and delete function, for the iArg'th
** argument to the user-function defined by pCtx. Any previous value is
** deleted by calling the delete function specified when it was set.
*/
void sqlite3_set_auxdata(
  sqlite3_context *pCtx, 
  int iArg, 
  void *pAux, 
  void (*xDelete)(void*)
){
  struct AuxData *pAuxData;
  VdbeFunc *pVdbeFunc;
  if( iArg<0 ) return;

  pVdbeFunc = pCtx->pVdbeFunc;
  if( !pVdbeFunc || pVdbeFunc->nAux<=iArg ){
    int nMalloc = sizeof(VdbeFunc) + sizeof(struct AuxData)*iArg;
    pCtx->pVdbeFunc = pVdbeFunc = sqliteRealloc(pVdbeFunc, nMalloc);
    if( !pVdbeFunc ) return;
    pVdbeFunc->nAux = iArg+1;
    pVdbeFunc->pFunc = pCtx->pFunc;
  }

  pAuxData = &pVdbeFunc->apAux[iArg];
  if( pAuxData->pAux && pAuxData->xDelete ){
    pAuxData->xDelete(pAuxData->pAux);
  }
  pAuxData->pAux = pAux;
  pAuxData->xDelete = xDelete;
}

  rc = sqlite3VdbeReset(p, pzErrMsg);
  sqlite3VdbeDelete(p);
  if( rc==SQLITE_SCHEMA ){
    sqlite3ResetInternalSchema(db, 0);
  }
  return rc;
}

/*
** Call the destructor for each auxdata entry in pVdbeFunc for which
** the corresponding bit in mask is set.  Auxdata entries beyond 31
** are always destroyed.  To destroy all auxdata entries, call this
** routine with mask==-1.
*/
void sqlite3VdbeDeleteAuxData(VdbeFunc *pVdbeFunc, int mask){
  int i;
  for(i=0; i<pVdbeFunc->nAux; i++){
    struct AuxData *pAux = &pVdbeFunc->apAux[i];
    if( (i>31 || !(mask&(1<<i))) && pAux->pAux ){
      if( pAux->xDelete ){
        pAux->xDelete(pAux->pAux);
      }
      pAux->pAux = 0;
    }
  }
}

/*
** Delete an entire VDBE.
*/
void sqlite3VdbeDelete(Vdbe *p){
  int i;
  if( p==0 ) return;

    Op *pOp = &p->aOp[i];
    if( pOp->p3type==P3_DYNAMIC || pOp->p3type==P3_KEYINFO ){
      sqliteFree(pOp->p3);
    }
    if( pOp->p3type==P3_VDBEFUNC ){
      int j;
      VdbeFunc *pVdbeFunc = (VdbeFunc *)pOp->p3;
      sqlite3VdbeDeleteAuxData(pVdbeFunc, -1);





      sqliteFree(pVdbeFunc);
    }
#ifndef NDEBUG
    sqliteFree(pOp->zComment);
#endif
  }
  for(i=0; i<p->nVar; i++){