SQLite

  return SQLITE_OK;
}

/*
** Cause any pending operation to stop at its earliest opportunity.
*/
void sqlite3_interrupt(sqlite3 *db){

  db->u1.isInterrupted = 1;
}


/*
** This function is exactly the same as sqlite3_create_function(), except
** that it is designed to be called by internal code. The difference is
** that if a malloc() fails in sqlite3_create_function(), an error code

  /* Allocate the parsing context */
  pParse = sqlite3StackAllocZero(db, sizeof(*pParse));
  if( pParse==0 ){
    rc = SQLITE_NOMEM;
    goto end_prepare;
  }
  pParse->pReprepare = pReprepare;

  assert( ppStmt && *ppStmt==0 );
  assert( !db->mallocFailed );
  assert( sqlite3_mutex_held(db->mutex) );

  /* Check to verify that it is possible to get a read lock on all
  ** database schemas.  The inability to get a read lock indicates that
  ** some other database connection is holding a write-lock, which in

#endif
  void(*xCollNeeded)(void*,sqlite3*,int eTextRep,const char*);
  void(*xCollNeeded16)(void*,sqlite3*,int eTextRep,const void*);
  void *pCollNeededArg;
  sqlite3_value *pErr;          /* Most recent error message */
  char *zErrMsg;                /* Most recent error message (UTF-8 encoded) */
  char *zErrMsg16;              /* Most recent error message (UTF-16 encoded) */
  union {
    volatile int isInterrupted; /* True if sqlite3_interrupt has been called */
    double notUsed1;            /* Spacer */
  } u1;
  Lookaside lookaside;          /* Lookaside malloc configuration */
#ifndef SQLITE_OMIT_AUTHORIZATION
  int (*xAuth)(void*,int,const char*,const char*,const char*,const char*);
                                /* Access authorization function */
  void *pAuthArg;               /* 1st argument to the access auth function */
#endif
#ifndef SQLITE_OMIT_PROGRESS_CALLBACK

** list.
*/
struct Parse {
  sqlite3 *db;         /* The main database structure */
  char *zErrMsg;       /* An error message */
  Vdbe *pVdbe;         /* An engine for executing database bytecode */
  int rc;              /* Return code from execution */

  u8 colNamesSet;      /* TRUE after OP_ColumnName has been issued to pVdbe */
  u8 checkSchema;      /* Causes schema cookie check after an error */
  u8 nested;           /* Number of nested calls to the parser/code generator */
  u8 nTempReg;         /* Number of temporary registers in aTempReg[] */
  u8 nTempInUse;       /* Number of aTempReg[] currently checked out */
  u8 nColCache;        /* Number of entries in aColCache[] */
  u8 iColCache;        /* Next entry in aColCache[] to replace */

  int lastTokenParsed = -1;       /* type of the previous token */
  u8 enableLookaside;             /* Saved value of db->lookaside.bEnabled */
  sqlite3 *db = pParse->db;       /* The database connection */
  int mxSqlLen;                   /* Max length of an SQL string */


  mxSqlLen = db->aLimit[SQLITE_LIMIT_SQL_LENGTH];
  if( db->activeVdbeCnt==0 ){
    db->u1.isInterrupted = 0;
  }
  pParse->rc = SQLITE_OK;
  pParse->zTail = zSql;
  i = 0;
  assert( pzErrMsg!=0 );
  pEngine = sqlite3ParserAlloc((void*(*)(size_t))sqlite3Malloc);
  if( pEngine==0 ){
    db->mallocFailed = 1;

    i += pParse->sLastToken.n;
    if( i>mxSqlLen ){
      pParse->rc = SQLITE_TOOBIG;
      break;
    }
    switch( tokenType ){
      case TK_SPACE: {
        if( db->u1.isInterrupted ){
          sqlite3ErrorMsg(pParse, "interrupt");
          pParse->rc = SQLITE_INTERRUPT;
          goto abort_parse;
        }
        break;
      }
      case TK_ILLEGAL: {

**
** This macro added to every instruction that does a jump in order to
** implement a loop.  This test used to be on every single instruction,
** but that meant we more testing than we needed.  By only testing the
** flag on jump instructions, we get a (small) speed improvement.
*/
#define CHECK_FOR_INTERRUPT \
   if( db->u1.isInterrupted ) goto abort_due_to_interrupt;


#ifndef NDEBUG
/*
** This function is only called from within an assert() expression. It
** checks that the sqlite3.nTransaction variable is correctly set to
** the number of non-transaction savepoints currently in the 

  }
  goto vdbe_error_halt;

  /* Jump to here if the sqlite3_interrupt() API sets the interrupt
  ** flag.
  */
abort_due_to_interrupt:
  assert( db->u1.isInterrupted );
  rc = SQLITE_INTERRUPT;
  p->rc = rc;
  sqlite3SetString(&p->zErrMsg, db, "%s", sqlite3ErrStr(rc));
  goto vdbe_error_halt;
}

  Mem *aVar;              /* Values for the OP_Variable opcode. */
  char **azVar;           /* Name of variables */
  ynVar nVar;             /* Number of entries in aVar[] */
  ynVar nzVar;            /* Number of entries in azVar[] */
  u32 cacheCtr;           /* VdbeCursor row cache generation counter */
  int pc;                 /* The program counter */
  int rc;                 /* Value to return */

  u8 errorAction;         /* Recovery action to do in case of an error */
  u8 explain;             /* True if EXPLAIN present on SQL command */
  u8 changeCntOn;         /* True to update the change-counter */
  u8 expired;             /* True if the VM needs to be recompiled */
  u8 runOnlyOnce;         /* Automatically expire on reset */
  u8 minWriteFileFormat;  /* Minimum file format for writable database files */
  u8 inVtabMethod;        /* See comments above */

  if( p->pc<=0 && p->expired ){
    p->rc = SQLITE_SCHEMA;
    rc = SQLITE_ERROR;
    goto end_of_step;
  }
  if( p->pc<0 ){
    /* If there are no other statements currently running, then
    ** reset the interrupt flag.  This prevents a call to sqlite3_interrupt
    ** from interrupting a statement that has not yet started.
    */
    if( db->activeVdbeCnt==0 ){
      db->u1.isInterrupted = 0;
    }

    assert( db->writeVdbeCnt>0 || db->autoCommit==0 || db->nDeferredCons==0 );

#ifndef SQLITE_OMIT_TRACE
    if( db->xProfile && !db->init.busy ){
      sqlite3OsCurrentTimeInt64(db->pVfs, &p->startTime);
    }
#endif

    db->activeVdbeCnt++;
    if( p->readOnly==0 ) db->writeVdbeCnt++;
    p->pc = 0;

  }
#ifndef SQLITE_OMIT_EXPLAIN
  if( p->explain ){
    rc = sqlite3VdbeList(p);
  }else
#endif /* SQLITE_OMIT_EXPLAIN */
  {

  do{
    i = p->pc++;
  }while( i<nRow && p->explain==2 && p->aOp[i].opcode!=OP_Explain );
  if( i>=nRow ){
    p->rc = SQLITE_OK;
    rc = SQLITE_DONE;
  }else if( db->u1.isInterrupted ){
    p->rc = SQLITE_INTERRUPT;
    rc = SQLITE_ERROR;
    sqlite3SetString(&p->zErrMsg, db, "%s", sqlite3ErrStr(p->rc));
  }else{
    char *z;
    Op *pOp;
    if( i<p->nOp ){
      /* The output line number is small enough that we are still in the