/*- * See the file LICENSE for redistribution information. * * Copyright (c) 1997-2003 * Sleepycat Software. All rights reserved. * * $Id: cxx_int.h,v 1.2 2004/03/30 01:21:28 jtownsen Exp $ */ #ifndef _CXX_INT_H_ #define _CXX_INT_H_ // private data structures known to the implementation only // // Using FooImp classes will allow the implementation to change in the // future without any modification to user code or even to header files // that the user includes. FooImp * is just like void * except that it // provides a little extra protection, since you cannot randomly assign // any old pointer to a FooImp* as you can with void *. Currently, a // pointer to such an opaque class is always just a pointer to the // appropriate underlying implementation struct. These are converted // back and forth using the various overloaded wrap()/unwrap() methods. // This is essentially a use of the "Bridge" Design Pattern. // // WRAPPED_CLASS implements the appropriate wrap() and unwrap() methods // for a wrapper class that has an underlying pointer representation. // #define WRAPPED_CLASS(_WRAPPER_CLASS, _IMP_CLASS, _WRAPPED_TYPE) \ \ class _IMP_CLASS {}; \ \ inline _WRAPPED_TYPE unwrap(_WRAPPER_CLASS *val) \ { \ if (!val) return (0); \ return ((_WRAPPED_TYPE)((void *)(val->imp()))); \ } \ \ inline const _WRAPPED_TYPE unwrapConst(const _WRAPPER_CLASS *val) \ { \ if (!val) return (0); \ return ((const _WRAPPED_TYPE)((void *)(val->constimp()))); \ } \ \ inline _IMP_CLASS *wrap(_WRAPPED_TYPE val) \ { \ return ((_IMP_CLASS*)((void *)val)); \ } WRAPPED_CLASS(DbMpoolFile, DbMpoolFileImp, DB_MPOOLFILE*) WRAPPED_CLASS(Db, DbImp, DB*) WRAPPED_CLASS(DbEnv, DbEnvImp, DB_ENV*) WRAPPED_CLASS(DbTxn, DbTxnImp, DB_TXN*) // A tristate integer value used by the DB_ERROR macro below. // We chose not to make this an enumerated type so it can // be kept private, even though methods that return the // tristate int can be declared in db_cxx.h . // #define ON_ERROR_THROW 1 #define ON_ERROR_RETURN 0 #define ON_ERROR_UNKNOWN (-1) // Macros that handle detected errors, in case we want to // change the default behavior. The 'policy' is one of // the tristate values given above. If UNKNOWN is specified, // the behavior is taken from the last initialized DbEnv. // #define DB_ERROR(env, caller, ecode, policy) \ DbEnv::runtime_error(env, caller, ecode, policy) #define DB_ERROR_DBT(env, caller, dbt, policy) \ DbEnv::runtime_error_dbt(env, caller, dbt, policy) #define DB_OVERFLOWED_DBT(dbt) \ (F_ISSET(dbt, DB_DBT_USERMEM) && dbt->size > dbt->ulen) /* values for Db::flags_ */ #define DB_CXX_PRIVATE_ENV 0x00000001 #endif /* !_CXX_INT_H_ */