SQLite

      return 0;
    }

    pInfo = pToplevel->pAinc;
    while( pInfo && pInfo->pTab!=pTab ){ pInfo = pInfo->pNext; }
    if( pInfo==0 ){
      pInfo = sqlite3DbMallocRawNN(pParse->db, sizeof(*pInfo));
      sqlite3ParserAddCleanup(pToplevel, sqlite3DbFree, pInfo);
      testcase( pParse->earlyCleanup );
      if( pInfo==0 ) return 0;
      if( pParse->db->mallocFailed ) return 0;
      pInfo->pNext = pToplevel->pAinc;
      pToplevel->pAinc = pInfo;
      pInfo->pTab = pTab;
      pInfo->iDb = iDb;
      pToplevel->nMem++;                  /* Register to hold name of table */
      pInfo->regCtr = ++pToplevel->nMem;  /* Max rowid register */
      pToplevel->nMem +=2;       /* Rowid in sqlite_sequence + orig max val */

  sqlite3 *db = pParse->db;
  AggInfo *pThis = pParse->pAggList;
  while( pThis ){
    AggInfo *pNext = pThis->pNext;
    agginfoFree(db, pThis);
    pThis = pNext;
  }
  while( pParse->pCleanup ){
    ParseCleanup *pThis = pParse->pCleanup;
    pParse->pCleanup = pThis->pNext;
    pThis->xCleanup(db, pThis->pPtr);
    sqlite3DbFree(db, pThis);
  }
  sqlite3DbFree(db, pParse->aLabel);
  if( pParse->pConstExpr ){
  sqlite3ExprListDelete(db, pParse->pConstExpr);
    sqlite3ExprListDelete(db, pParse->pConstExpr);
  }
  if( db ){
    assert( db->lookaside.bDisable >= pParse->disableLookaside );
    db->lookaside.bDisable -= pParse->disableLookaside;
    db->lookaside.sz = db->lookaside.bDisable ? 0 : db->lookaside.szTrue;
  }
  pParse->disableLookaside = 0;
}

/*
** Add a new cleanup operation to a Parser.  The cleanup should happen when
** the parser object is destroyed.  But, beware: the cleanup might happen
** immediately.
**
** Use this mechanism for uncommon cleanups.  There is a higher setup
** cost for this mechansim (an extra malloc), so it should not be used
** for common cleanups that happen on most calls.  But for less
** common cleanups, we save a single NULL-pointer comparison in
** sqlite3ParserReset(), which reduces the total CPU cycle count.
**
** If a memory allocation error occurs, then the cleanup happens immediately.
** When eithr SQLITE_DEBUG or SQLITE_COVERAGE_TEST are defined, the
** pParse->earlyCleanup flag is set in that case.  Calling code show verify
** that test cases exist for which this happens, to guard against possible
** use-after-free errors following an OOM.  The preferred way to do this is
** to immediately follow the call to this routine with:
**
**       testcase( pParse->earlyCleanup );
*/
void sqlite3ParserAddCleanup(
  Parse *pParse,                      /* Destroy when this Parser finishes */
  void (*xCleanup)(sqlite3*,void*),   /* The cleanup routine */
  void *pPtr                          /* Pointer to object to be cleaned up */
){
  ParseCleanup *pCleanup = sqlite3DbMallocRaw(pParse->db, sizeof(*pCleanup));
  if( pCleanup ){
    pCleanup->pNext = pParse->pCleanup;
    pParse->pCleanup = pCleanup;
    pCleanup->pPtr = pPtr;
    pCleanup->xCleanup = xCleanup;
  }else{
    xCleanup(pParse->db, pPtr);
#if defined(SQLITE_DEBUG) || defined(SQLITE_COVERAGE_TEST)
    pParse->earlyCleanup = 1;
#endif
  }
}

/*
** Compile the UTF-8 encoded SQL statement zSql into a statement handle.
*/
static int sqlite3Prepare(
  sqlite3 *db,              /* Database handle. */
  const char *zSql,         /* UTF-8 encoded SQL statement. */

  **
  ** pSubitem->pTab is always non-NULL by test restrictions and tests above.
  */
  if( ALWAYS(pSubitem->pTab!=0) ){
    Table *pTabToDel = pSubitem->pTab;
    if( pTabToDel->nTabRef==1 ){
      Parse *pToplevel = sqlite3ParseToplevel(pParse);
      sqlite3ParserAddCleanup(pToplevel, 
         (void(*)(sqlite3*,void*))sqlite3DeleteTable,
      pTabToDel->pNextZombie = pToplevel->pZombieTab;
      pToplevel->pZombieTab = pTabToDel;
         pTabToDel);
      testcase( pToplevel->earlyCleanup );
    }else{
      pTabToDel->nTabRef--;
    }
    pSubitem->pTab = 0;
  }

  /* The following loop runs once for each term in a compound-subquery

** onto the top of the stack. If argument bFree is true, then this
** WITH clause will never be popped from the stack. In this case it
** should be freed along with the Parse object. In other cases, when
** bFree==0, the With object will be freed along with the SELECT 
** statement with which it is associated.
*/
void sqlite3WithPush(Parse *pParse, With *pWith, u8 bFree){
  assert( bFree==0 || (pParse->pWith==0 && pParse->pWithToFree==0) );
  if( pWith ){
    assert( pParse->pWith!=pWith );
    pWith->pOuter = pParse->pWith;
    pParse->pWith = pWith;
    if( bFree ) pParse->pWithToFree = pWith;
    if( bFree ){
      sqlite3ParserAddCleanup(pParse, 
         (void(*)(sqlite3*,void*))sqlite3WithDelete,
         pWith);
      testcase( pParse->earlyCleanup );
    }
  }
}

/*
** This function checks if argument pFrom refers to a CTE declared by 
** a WITH clause on the stack currently maintained by the parser. And,
** if currently processing a CTE expression, if it is a recursive

typedef struct KeyClass KeyClass;
typedef struct KeyInfo KeyInfo;
typedef struct Lookaside Lookaside;
typedef struct LookasideSlot LookasideSlot;
typedef struct Module Module;
typedef struct NameContext NameContext;
typedef struct Parse Parse;
typedef struct ParseCleanup ParseCleanup;
typedef struct PreUpdate PreUpdate;
typedef struct PrintfArguments PrintfArguments;
typedef struct RenameToken RenameToken;
typedef struct RowSet RowSet;
typedef struct Savepoint Savepoint;
typedef struct Select Select;
typedef struct SQLiteThread SQLiteThread;

#ifndef SQLITE_OMIT_VIRTUALTABLE
  int nModuleArg;      /* Number of arguments to the module */
  char **azModuleArg;  /* 0: module 1: schema 2: vtab name 3...: args */
  VTable *pVTable;     /* List of VTable objects. */
#endif
  Trigger *pTrigger;   /* List of triggers stored in pSchema */
  Schema *pSchema;     /* Schema that contains this table */
  Table *pNextZombie;  /* Next on the Parse.pZombieTab list */
};

/*
** Allowed values for Table.tabFlags.
**
** TF_OOOHidden applies to tables or view that have hidden columns that are
** followed by non-hidden columns.  Example:  "CREATE VIRTUAL TABLE x USING

# define DbMaskTest(M,I)    (((M)&(((yDbMask)1)<<(I)))!=0)
# define DbMaskZero(M)      (M)=0
# define DbMaskSet(M,I)     (M)|=(((yDbMask)1)<<(I))
# define DbMaskAllZero(M)   (M)==0
# define DbMaskNonZero(M)   (M)!=0
#endif

/*
** An instance of the ParseCleanup object specifies an operation that
** should be performed after parsing to deallocation resources obtained
** during the parse and which are no longer needed.
*/
struct ParseCleanup {
  ParseCleanup *pNext;               /* Next cleanup task */
  void *pPtr;                        /* Pointer to object to deallocate */
  void (*xCleanup)(sqlite3*,void*);  /* Deallocation routine */
};

/*
** 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.
**
** The structure is divided into two parts.  When the parser and code
** generate call themselves recursively, the first part of the structure

  u8 nTempReg;         /* Number of temporary registers in aTempReg[] */
  u8 isMultiWrite;     /* True if statement may modify/insert multiple rows */
  u8 mayAbort;         /* True if statement may throw an ABORT exception */
  u8 hasCompound;      /* Need to invoke convertCompoundSelectToSubquery() */
  u8 okConstFactor;    /* OK to factor out constants */
  u8 disableLookaside; /* Number of times lookaside has been disabled */
  u8 disableVtab;      /* Disable all virtual tables for this parse */
#if defined(SQLITE_DEBUG) || defined(SQLITE_COVERAGE_TEST)
  u8 earlyCleanup;     /* OOM inside sqlite3ParserAddCleanup() */
#endif
  int nRangeReg;       /* Size of the temporary register block */
  int iRangeReg;       /* First register in temporary register block */
  int nErr;            /* Number of errors seen */
  int nTab;            /* Number of previously allocated VDBE cursors */
  int nMem;            /* Number of memory cells used so far */
  int szOpAlloc;       /* Bytes of memory space allocated for Vdbe.aOp[] */
  int iSelfTab;        /* Table associated with an index on expr, or negative

                            ** during a RENAME COLUMN */
  Trigger *pNewTrigger;     /* Trigger under construct by a CREATE TRIGGER */
  const char *zAuthContext; /* The 6th parameter to db->xAuth callbacks */
#ifndef SQLITE_OMIT_VIRTUALTABLE
  Token sArg;               /* Complete text of a module argument */
  Table **apVtabLock;       /* Pointer to virtual tables needing locking */
#endif
  Table *pZombieTab;        /* List of Table objects to delete after code gen */
  TriggerPrg *pTriggerPrg;  /* Linked list of coded triggers */
  With *pWith;              /* Current WITH clause, or NULL */
  With *pWithToFree;        /* Free this WITH object at the end of the parse */
  ParseCleanup *pCleanup;   /* List of cleanup operations to run after parse */
#ifndef SQLITE_OMIT_ALTERTABLE
  RenameToken *pRename;     /* Tokens subject to renaming by ALTER TABLE */
#endif
};

#define PARSE_MODE_NORMAL        0
#define PARSE_MODE_DECLARE_VTAB  1

int sqlite3VtabCallDestroy(sqlite3*, int, const char *);
int sqlite3VtabBegin(sqlite3 *, VTable *);
FuncDef *sqlite3VtabOverloadFunction(sqlite3 *,FuncDef*, int nArg, Expr*);
sqlite3_int64 sqlite3StmtCurrentTime(sqlite3_context*);
int sqlite3VdbeParameterIndex(Vdbe*, const char*, int);
int sqlite3TransferBindings(sqlite3_stmt *, sqlite3_stmt *);
void sqlite3ParserReset(Parse*);
void sqlite3ParserAddCleanup(Parse*,void(*)(sqlite3*,void*),void*);
#ifdef SQLITE_ENABLE_NORMALIZE
char *sqlite3Normalize(Vdbe*, const char*);
#endif
int sqlite3Reprepare(Vdbe*);
void sqlite3ExprListCheckLength(Parse*, ExprList*, const char*);
CollSeq *sqlite3ExprCompareCollSeq(Parse*,const Expr*);
CollSeq *sqlite3BinaryCompareCollSeq(Parse *, const Expr*, const Expr*);

    ** will take responsibility for freeing the Table structure.
    */
    sqlite3DeleteTable(db, pParse->pNewTable);
  }
  if( !IN_RENAME_OBJECT ){
    sqlite3DeleteTrigger(db, pParse->pNewTrigger);
  }

  if( pParse->pWithToFree ) sqlite3WithDelete(db, pParse->pWithToFree);
  sqlite3DbFree(db, pParse->pVList);
  while( pParse->pAinc ){
    AutoincInfo *p = pParse->pAinc;
    pParse->pAinc = p->pNext;
    sqlite3DbFreeNN(db, p);
  }
  while( pParse->pZombieTab ){
    Table *p = pParse->pZombieTab;
    pParse->pZombieTab = p->pNextZombie;
    sqlite3DeleteTable(db, p);
  }
  db->pParse = pParse->pParentParse;
  pParse->pParentParse = 0;
  assert( nErr==0 || pParse->rc!=SQLITE_OK );
  return nErr;
}

    pProgram->nCsr = pSubParse->nTab;
    pProgram->token = (void *)pTrigger;
    pPrg->aColmask[0] = pSubParse->oldmask;
    pPrg->aColmask[1] = pSubParse->newmask;
    sqlite3VdbeDelete(v);
  }

  assert( !pSubParse->pAinc       && !pSubParse->pZombieTab );
  assert( !pSubParse->pTriggerPrg && !pSubParse->nMaxArg );
  sqlite3ParserReset(pSubParse);
  sqlite3StackFree(db, pSubParse);

  return pPrg;
}