db_cxx.h

/* DO NOT EDIT: automatically built by dist/s_win32. */
/*-
 * See the file LICENSE for redistribution information.
 *
 * Copyright (c) 1997-2005
 *      Sleepycat Software.  All rights reserved.
 *
 * $Id: db_cxx.in,v 12.13 2005/10/18 14:17:08 mjc Exp $
 */

#ifndef _DB_CXX_H_
#define _DB_CXX_H_
//
// C++ assumptions:
//
// To ensure portability to many platforms, both new and old, we make
// few assumptions about the C++ compiler and library.  For example,
// we do not expect STL, templates or namespaces to be available.  The
// "newest" C++ feature used is exceptions, which are used liberally
// to transmit error information.  Even the use of exceptions can be
// disabled at runtime, to do so, use the DB_CXX_NO_EXCEPTIONS flags
// with the DbEnv or Db constructor.
//
// C++ naming conventions:
//
//  - All top level class names start with Db.
//  - All class members start with lower case letter.
//  - All private data members are suffixed with underscore.
//  - Use underscores to divide names into multiple words.
//  - Simple data accessors are named with get_ or set_ prefix.
//  - All method names are taken from names of functions in the C
//    layer of db (usually by dropping a prefix like "db_").
//    These methods have the same argument types and order,
//    other than dropping the explicit arg that acts as "this".
//
// As a rule, each DbFoo object has exactly one underlying DB_FOO struct
// (defined in db.h) associated with it.  In some cases, we inherit directly
// from the DB_FOO structure to make this relationship explicit.  Often,
// the underlying C layer allocates and deallocates these structures, so
// there is no easy way to add any data to the DbFoo class.  When you see
// a comment about whether data is permitted to be added, this is what
// is going on.  Of course, if we need to add data to such C++ classes
// in the future, we will arrange to have an indirect pointer to the
// DB_FOO struct (as some of the classes already have).
//

//
// Forward declarations
//

#include <stdarg.h>

#define HAVE_CXX_STDHEADERS 1
#ifdef HAVE_CXX_STDHEADERS
#include <iostream>
#include <exception>
#define __DB_STD(x)     std::x
#else
#include <iostream.h>
#include <exception.h>
#define __DB_STD(x)     x
#endif

#include "db.h"

class Db;                                        // forward
class Dbc;                                       // forward
class DbEnv;                                     // forward
class DbInfo;                                    // forward
class DbLock;                                    // forward
class DbLogc;                                    // forward
class DbLsn;                                     // forward
class DbMpoolFile;                               // forward
class DbPreplist;                                // forward
class Dbt;                                       // forward
class DbTxn;                                     // forward
class DbLock;                                    // forward
class DbSequence;                                // forward
class Dbt;                                       // forward

class DbMultipleIterator;                        // forward
class DbMultipleKeyDataIterator;                 // forward
class DbMultipleRecnoDataIterator;               // forward
class DbMultipleDataIterator;                    // forward

class DbException;                               // forward
class DbDeadlockException;                       // forward
class DbLockNotGrantedException;                 // forward
class DbMemoryException;                         // forward
class DbRepHandleDeadException;                  // forward
class DbRunRecoveryException;                    // forward

//
// Turn off inappropriate compiler warnings
//

#ifdef _MSC_VER

// These are level 4 warnings that are explicitly disabled.
// With Visual C++, by default you do not see above level 3 unless
// you use /W4.  But we like to compile with the highest level
// warnings to catch other errors.
//
// 4201: nameless struct/union
//       triggered by standard include file <winnt.h>
//
// 4514: unreferenced inline function has been removed
//       certain include files in MSVC define methods that are not called
//
#pragma warning(disable: 4201 4514)

#endif

//
// Mechanisms for declaring classes
//

//
// Every class defined in this file has an _exported next to the class name.
// This is needed for WinTel machines so that the class methods can
// be exported or imported in a DLL as appropriate.  Users of the DLL
// use the define DB_USE_DLL.  When the DLL is built, DB_CREATE_DLL
// must be defined.
//
#if defined(_MSC_VER)

#  if defined(DB_CREATE_DLL)
#    define _exported __declspec(dllexport)      // creator of dll
#  elif defined(DB_USE_DLL)
#    define _exported __declspec(dllimport)      // user of dll
#  else
#    define _exported                            // static lib creator or user
#  endif

#else /* _MSC_VER */

#  define _exported

#endif /* _MSC_VER */

// Some interfaces can be customized by allowing users to define
// callback functions.  For performance and logistical reasons, some
// callback functions must be declared in extern "C" blocks.  For others,
// we allow you to declare the callbacks in C++ or C (or an extern "C"
// block) as you wish.  See the set methods for the callbacks for
// the choices.
//
extern "C" {
        typedef void * (*db_malloc_fcn_type)
                (size_t);
        typedef void * (*db_realloc_fcn_type)
                (void *, size_t);
        typedef void (*db_free_fcn_type)
                (void *);
        typedef int (*bt_compare_fcn_type)          /*C++ version available*/
                (DB *, const DBT *, const DBT *);
        typedef size_t (*bt_prefix_fcn_type)        /*C++ version available*/
                (DB *, const DBT *, const DBT *);
        typedef int (*dup_compare_fcn_type)         /*C++ version available*/
                (DB *, const DBT *, const DBT *);
        typedef u_int32_t (*h_hash_fcn_type)        /*C++ version available*/
                (DB *, const void *, u_int32_t);
        typedef int (*pgin_fcn_type)
                (DB_ENV *dbenv, db_pgno_t pgno, void *pgaddr, DBT *pgcookie);
        typedef int (*pgout_fcn_type)
                (DB_ENV *dbenv, db_pgno_t pgno, void *pgaddr, DBT *pgcookie);
}

//
// Represents a database table = a set of keys with associated values.
//
class _exported Db
{
        friend class DbEnv;

public:
        Db(DbEnv*, u_int32_t);      // Create a Db object.
        virtual ~Db();              // Calls close() if the user hasn't.

        // These methods exactly match those in the C interface.
        //
        virtual int associate(DbTxn *txn, Db *secondary,
            int (*callback)(Db *, const Dbt *, const Dbt *, Dbt *),
            u_int32_t flags);
        virtual int close(u_int32_t flags);
        virtual int compact(DbTxn *txnid, Dbt *start, Dbt *stop,
            DB_COMPACT *c_data, u_int32_t flags, Dbt *end);
        virtual int cursor(DbTxn *txnid, Dbc **cursorp, u_int32_t flags);
        virtual int del(DbTxn *txnid, Dbt *key, u_int32_t flags);
        virtual void err(int, const char *, ...);
        virtual void errx(const char *, ...);
        virtual int fd(int *fdp);
        virtual int get(DbTxn *txnid, Dbt *key, Dbt *data, u_int32_t flags);
        virtual void *get_app_private() const;
        virtual int get_byteswapped(int *);
        virtual int get_dbname(const char **, const char **);
        virtual int get_open_flags(u_int32_t *);
        virtual int get_type(DBTYPE *);
        virtual int get_transactional();
        virtual int join(Dbc **curslist, Dbc **dbcp, u_int32_t flags);
        virtual int key_range(DbTxn *, Dbt *, DB_KEY_RANGE *, u_int32_t);
        virtual int open(DbTxn *txnid,
            const char *, const char *subname, DBTYPE, u_int32_t, int);
        virtual int pget(DbTxn *txnid, Dbt *key, Dbt *pkey, Dbt *data,
            u_int32_t flags);
        virtual int put(DbTxn *, Dbt *, Dbt *, u_int32_t);
        virtual int remove(const char *, const char *, u_int32_t);
        virtual int rename(const char *, const char *, const char *, u_int32_t);
        virtual int set_alloc(db_malloc_fcn_type, db_realloc_fcn_type,
            db_free_fcn_type);
        virtual void set_app_private(void *);
        virtual int set_append_recno(int (*)(Db *, Dbt *, db_recno_t));
        virtual int set_bt_compare(bt_compare_fcn_type); /*deprecated*/
        virtual int set_bt_compare(int (*)(Db *, const Dbt *, const Dbt *));
        virtual int get_bt_minkey(u_int32_t *);
        virtual int set_bt_minkey(u_int32_t);
        virtual int set_bt_prefix(bt_prefix_fcn_type); /*deprecated*/
        virtual int set_bt_prefix(size_t (*)(Db *, const Dbt *, const Dbt *));
        virtual int get_cachesize(u_int32_t *, u_int32_t *, int *);
        virtual int set_cachesize(u_int32_t, u_int32_t, int);
        virtual int set_dup_compare(dup_compare_fcn_type); /*deprecated*/
        virtual int set_dup_compare(int (*)(Db *, const Dbt *, const Dbt *));
        virtual int get_encrypt_flags(u_int32_t *);
        virtual int set_encrypt(const char *, u_int32_t);
        virtual void set_errcall(
            void (*)(const DbEnv *, const char *, const char *));
        virtual void get_errfile(FILE **);
        virtual void set_errfile(FILE *);
        virtual void get_errpfx(const char **);
        virtual void set_errpfx(const char *);
        virtual int set_feedback(void (*)(Db *, int, int));
        virtual int get_flags(u_int32_t *);
        virtual int set_flags(u_int32_t);
        virtual int get_h_ffactor(u_int32_t *);
        virtual int set_h_ffactor(u_int32_t);
        virtual int set_h_hash(h_hash_fcn_type); /*deprecated*/
        virtual int set_h_hash(u_int32_t (*)(Db *, const void *, u_int32_t));
        virtual int get_h_nelem(u_int32_t *);
        virtual int set_h_nelem(u_int32_t);
        virtual int get_lorder(int *);
        virtual int set_lorder(int);
        virtual void set_msgcall(void (*)(const DbEnv *, const char *));
        virtual void get_msgfile(FILE **);
        virtual void set_msgfile(FILE *);
        virtual int get_pagesize(u_int32_t *);
        virtual int set_pagesize(u_int32_t);
        virtual int set_paniccall(void (*)(DbEnv *, int));
        virtual int get_re_delim(int *);
        virtual int set_re_delim(int);
        virtual int get_re_len(u_int32_t *);
        virtual int set_re_len(u_int32_t);
        virtual int get_re_pad(int *);
        virtual int set_re_pad(int);
        virtual int get_re_source(const char **);
        virtual int set_re_source(const char *);
        virtual int get_q_extentsize(u_int32_t *);
        virtual int set_q_extentsize(u_int32_t);
        virtual int stat(DbTxn *, void *sp, u_int32_t flags);
        virtual int stat_print(u_int32_t flags);
        virtual int sync(u_int32_t flags);
        virtual int truncate(DbTxn *, u_int32_t *, u_int32_t);
        virtual int upgrade(const char *name, u_int32_t flags);
        virtual int verify(const char *, const char *, __DB_STD(ostream) *,
                      u_int32_t);

        // These additional methods are not in the C interface, and
        // are only available for C++.
        //
        virtual __DB_STD(ostream) *get_error_stream();
        virtual void set_error_stream(__DB_STD(ostream) *);
        virtual __DB_STD(ostream) *get_message_stream();
        virtual void set_message_stream(__DB_STD(ostream) *);

        virtual DbEnv *get_env();
        virtual DbMpoolFile *get_mpf();

        virtual DB *get_DB()
        {
                return imp_;
        }

        virtual const DB *get_const_DB() const
        {
                return imp_;
        }

        static Db* get_Db(DB *db)
        {
                return (Db *)db->api_internal;
        }

        static const Db* get_const_Db(const DB *db)
        {
                return (const Db *)db->api_internal;
        }

private:
        // no copying
        Db(const Db &);
        Db &operator = (const Db &);

        void cleanup();
        int initialize();
        int error_policy();

        // instance data
        DB *imp_;
        DbEnv *env_;
        DbMpoolFile *mpf_;
        int construct_error_;
        u_int32_t flags_;
        u_int32_t construct_flags_;

public:
        // These are public only because they need to be called
        // via C callback functions.  They should never be used by
        // external users of this class.
        //
        int (*append_recno_callback_)(Db *, Dbt *, db_recno_t);
        int (*associate_callback_)(Db *, const Dbt *, const Dbt *, Dbt *);
        int (*bt_compare_callback_)(Db *, const Dbt *, const Dbt *);
        size_t (*bt_prefix_callback_)(Db *, const Dbt *, const Dbt *);
        int (*dup_compare_callback_)(Db *, const Dbt *, const Dbt *);
        void (*feedback_callback_)(Db *, int, int);
        u_int32_t (*h_hash_callback_)(Db *, const void *, u_int32_t);
};

//
// Cursor
//
class _exported Dbc : protected DBC
{
        friend class Db;

public:
        int close();
        int count(db_recno_t *countp, u_int32_t flags);
        int del(u_int32_t flags);
        int dup(Dbc** cursorp, u_int32_t flags);
        int get(Dbt* key, Dbt *data, u_int32_t flags);
        int pget(Dbt* key, Dbt* pkey, Dbt *data, u_int32_t flags);
        int put(Dbt* key, Dbt *data, u_int32_t flags);

private:
        // No data is permitted in this class (see comment at top)

        // Note: use Db::cursor() to get pointers to a Dbc,
        // and call Dbc::close() rather than delete to release them.
        //
        Dbc();
        ~Dbc();

        // no copying
        Dbc(const Dbc &);
        Dbc &operator = (const Dbc &);
};

//
// Berkeley DB environment class.  Provides functions for opening databases.
// User of this library can use this class as a starting point for
// developing a DB application - derive their application class from
// this one, add application control logic.
//
// Note that if you use the default constructor, you must explicitly
// call appinit() before any other db activity (e.g. opening files)
//
class _exported DbEnv
{
        friend class Db;
        friend class DbLock;
        friend class DbMpoolFile;

public:
        // After using this constructor, you can set any needed
        // parameters for the environment using the set_* methods.
        // Then call open() to finish initializing the environment
        // and attaching it to underlying files.
        //
        DbEnv(u_int32_t flags);

        virtual ~DbEnv();

        // These methods match those in the C interface.
        //
        virtual int close(u_int32_t);
        virtual int dbremove(DbTxn *txn, const char *name, const char *subdb,
            u_int32_t flags);
        virtual int dbrename(DbTxn *txn, const char *name, const char *subdb,
            const char *newname, u_int32_t flags);
        virtual void err(int, const char *, ...);
        virtual void errx(const char *, ...);
        virtual int failchk(u_int32_t);
        virtual int fileid_reset(const char *, u_int32_t);
        virtual void *get_app_private() const;
        virtual int get_home(const char **);
        virtual int get_open_flags(u_int32_t *);
        virtual int open(const char *, u_int32_t, int);
        virtual int remove(const char *, u_int32_t);
        virtual int stat_print(u_int32_t flags);

        virtual int set_alloc(db_malloc_fcn_type, db_realloc_fcn_type,
                              db_free_fcn_type);
        virtual void set_app_private(void *);
        virtual int get_cachesize(u_int32_t *, u_int32_t *, int *);
        virtual int set_cachesize(u_int32_t, u_int32_t, int);
        virtual int get_data_dirs(const char ***);
        virtual int set_data_dir(const char *);
        virtual int get_encrypt_flags(u_int32_t *);
        virtual int set_intermediate_dir(int, u_int32_t);
        virtual int set_isalive(int (*)(DbEnv *, pid_t, db_threadid_t));
        virtual int set_encrypt(const char *, u_int32_t);
        virtual void set_errcall(
                        void (*)(const DbEnv *, const char *, const char *));
        virtual void get_errfile(FILE **);
        virtual void set_errfile(FILE *);
        virtual void get_errpfx(const char **);
        virtual void set_errpfx(const char *);
        virtual int get_flags(u_int32_t *);
        virtual int set_flags(u_int32_t, int);
        virtual bool is_bigendian();
        virtual int lsn_reset(const char *, u_int32_t);
        virtual int set_feedback(void (*)(DbEnv *, int, int));
        virtual int get_lg_bsize(u_int32_t *);
        virtual int set_lg_bsize(u_int32_t);
        virtual int get_lg_dir(const char **);
        virtual int set_lg_dir(const char *);
        virtual int get_lg_filemode(int *);
        virtual int set_lg_filemode(int);
        virtual int get_lg_max(u_int32_t *);
        virtual int set_lg_max(u_int32_t);
        virtual int get_lg_regionmax(u_int32_t *);
        virtual int set_lg_regionmax(u_int32_t);
        virtual int get_lk_conflicts(const u_int8_t **, int *);
        virtual int set_lk_conflicts(u_int8_t *, int);
        virtual int get_lk_detect(u_int32_t *);
        virtual int set_lk_detect(u_int32_t);
        virtual int set_lk_max(u_int32_t);
        virtual int get_lk_max_lockers(u_int32_t *);
        virtual int set_lk_max_lockers(u_int32_t);
        virtual int get_lk_max_locks(u_int32_t *);
        virtual int set_lk_max_locks(u_int32_t);
        virtual int get_lk_max_objects(u_int32_t *);
        virtual int set_lk_max_objects(u_int32_t);
        virtual int get_mp_mmapsize(size_t *);
        virtual int set_mp_mmapsize(size_t);
        virtual int get_mp_max_openfd(int *);
        virtual int set_mp_max_openfd(int);
        virtual int get_mp_max_write(int *, int *);
        virtual int set_mp_max_write(int, int);
        virtual void set_msgcall(void (*)(const DbEnv *, const char *));
        virtual void get_msgfile(FILE **);
        virtual void set_msgfile(FILE *);
        virtual int set_paniccall(void (*)(DbEnv *, int));
        virtual int set_rpc_server(void *, char *, long, long, u_int32_t);
        virtual int get_shm_key(long *);
        virtual int set_shm_key(long);
        virtual int get_timeout(db_timeout_t *, u_int32_t);
        virtual int set_timeout(db_timeout_t, u_int32_t);
        virtual int get_tmp_dir(const char **);
        virtual int set_tmp_dir(const char *);
        virtual int get_tx_max(u_int32_t *);
        virtual int set_tx_max(u_int32_t);
        virtual int set_app_dispatch(int (*)(DbEnv *,
            Dbt *, DbLsn *, db_recops));
        virtual int get_tx_timestamp(time_t *);
        virtual int set_tx_timestamp(time_t *);
        virtual int get_verbose(u_int32_t which, int *);
        virtual int set_verbose(u_int32_t which, int);

        // Version information.  A static method so it can be obtained anytime.
        //
        static char *version(int *major, int *minor, int *patch);

        // Convert DB errors to strings
        static char *strerror(int);

        // If an error is detected and the error call function
        // or stream is set, a message is dispatched or printed.
        // If a prefix is set, each message is prefixed.
        //
        // You can use set_errcall() or set_errfile() above to control
        // error functionality.  Alternatively, you can call
        // set_error_stream() to force all errors to a C++ stream.
        // It is unwise to mix these approaches.
        //
        virtual __DB_STD(ostream) *get_error_stream();
        virtual void set_error_stream(__DB_STD(ostream) *);
        virtual __DB_STD(ostream) *get_message_stream();
        virtual void set_message_stream(__DB_STD(ostream) *);

        // used internally
        static void runtime_error(DbEnv *env, const char *caller, int err,
                                  int error_policy);
        static void runtime_error_dbt(DbEnv *env, const char *caller, Dbt *dbt,
                                  int error_policy);
        static void runtime_error_lock_get(DbEnv *env, const char *caller,
                                  int err, db_lockop_t op, db_lockmode_t mode,
                                  const Dbt *obj, DbLock lock, int index,
                                  int error_policy);

        // Lock functions
        //
        virtual int lock_detect(u_int32_t flags, u_int32_t atype, int *aborted);
        virtual int lock_get(u_int32_t locker, u_int32_t flags, const Dbt *obj,
                     db_lockmode_t lock_mode, DbLock *lock);
        virtual int lock_id(u_int32_t *idp);
        virtual int lock_id_free(u_int32_t id);
        virtual int lock_put(DbLock *lock);
        virtual int lock_stat(DB_LOCK_STAT **statp, u_int32_t flags);
        virtual int lock_stat_print(u_int32_t flags);
        virtual int lock_vec(u_int32_t locker, u_int32_t flags,
                     DB_LOCKREQ list[], int nlist, DB_LOCKREQ **elistp);

        // Log functions
        //
        virtual int log_archive(char **list[], u_int32_t flags);
        static int log_compare(const DbLsn *lsn0, const DbLsn *lsn1);
        virtual int log_cursor(DbLogc **cursorp, u_int32_t flags);
        virtual int log_file(DbLsn *lsn, char *namep, size_t len);
        virtual int log_flush(const DbLsn *lsn);
        virtual int log_put(DbLsn *lsn, const Dbt *data, u_int32_t flags);
        virtual int log_printf(DbTxn *, const char *, ...);

        virtual int log_stat(DB_LOG_STAT **spp, u_int32_t flags);
        virtual int log_stat_print(u_int32_t flags);

        // Mpool functions
        //
        virtual int memp_fcreate(DbMpoolFile **dbmfp, u_int32_t flags);
        virtual int memp_register(int ftype,
                          pgin_fcn_type pgin_fcn,
                          pgout_fcn_type pgout_fcn);
        virtual int memp_stat(DB_MPOOL_STAT
                      **gsp, DB_MPOOL_FSTAT ***fsp, u_int32_t flags);
        virtual int memp_stat_print(u_int32_t flags);
        virtual int memp_sync(DbLsn *lsn);
        virtual int memp_trickle(int pct, int *nwrotep);

        // Mpool functions
        //
        virtual int mutex_alloc(u_int32_t, db_mutex_t *);
        virtual int mutex_free(db_mutex_t);
        virtual int mutex_get_align(u_int32_t *);
        virtual int mutex_get_increment(u_int32_t *);
        virtual int mutex_get_max(u_int32_t *);
        virtual int mutex_get_tas_spins(u_int32_t *);
        virtual int mutex_lock(db_mutex_t);
        virtual int mutex_set_align(u_int32_t);
        virtual int mutex_set_increment(u_int32_t);
        virtual int mutex_set_max(u_int32_t);
        virtual int mutex_set_tas_spins(u_int32_t);
        virtual int mutex_stat(DB_MUTEX_STAT **, u_int32_t);
        virtual int mutex_stat_print(u_int32_t);
        virtual int mutex_unlock(db_mutex_t);

        // Transaction functions
        //
        virtual int txn_begin(DbTxn *pid, DbTxn **tid, u_int32_t flags);
        virtual int txn_checkpoint(u_int32_t kbyte, u_int32_t min,
                        u_int32_t flags);
        virtual int txn_recover(DbPreplist *preplist, long count,
                        long *retp, u_int32_t flags);
        virtual int txn_stat(DB_TXN_STAT **statp, u_int32_t flags);
        virtual int txn_stat_print(u_int32_t flags);

        // Replication functions
        //
        virtual int rep_elect(int, int, int, u_int32_t, int *, u_int32_t);
        virtual int rep_flush();
        virtual int rep_process_message(Dbt *, Dbt *, int *, DbLsn *);
        virtual int rep_start(Dbt *, u_int32_t);
        virtual int rep_stat(DB_REP_STAT **statp, u_int32_t flags);
        virtual int rep_stat_print(u_int32_t flags);
        virtual int get_rep_limit(u_int32_t *, u_int32_t *);
        virtual int set_rep_limit(u_int32_t, u_int32_t);
        virtual int set_rep_transport(int, int (*)(DbEnv *,
            const Dbt *, const Dbt *, const DbLsn *, int, u_int32_t));
        virtual int set_rep_request(u_int32_t, u_int32_t);
        virtual int set_thread_count(u_int32_t);
        virtual int set_thread_id(void (*)(DbEnv *, pid_t *, db_threadid_t *));
        virtual int set_thread_id_string(char *(*)(DbEnv *, pid_t, db_threadid_t, char *));
        virtual int rep_set_config(u_int32_t which, int onoff);
        virtual int rep_get_config(u_int32_t which, int *onoffp);
        virtual int rep_sync(u_int32_t flags);

        // Conversion functions
        //
        virtual DB_ENV *get_DB_ENV()
        {
                return imp_;
        }

        virtual const DB_ENV *get_const_DB_ENV() const
        {
                return imp_;
        }

        static DbEnv* get_DbEnv(DB_ENV *dbenv)
        {
                return dbenv ? (DbEnv *)dbenv->api1_internal : 0;
        }

        static const DbEnv* get_const_DbEnv(const DB_ENV *dbenv)
        {
                return dbenv ? (const DbEnv *)dbenv->api1_internal : 0;
        }

        // For internal use only.
        static DbEnv* wrap_DB_ENV(DB_ENV *dbenv);

        // These are public only because they need to be called
        // via C functions.  They should never be called by users
        // of this class.
        //
        static int _app_dispatch_intercept(DB_ENV *env, DBT *dbt, DB_LSN *lsn,
                                       db_recops op);
        static void _paniccall_intercept(DB_ENV *env, int errval);
        static void _feedback_intercept(DB_ENV *env, int opcode, int pct);
        static int _isalive_intercept(DB_ENV *env, pid_t pid,
            db_threadid_t thrid);
        static int _rep_send_intercept(DB_ENV *env, const DBT *cntrl,
            const DBT *data, const DB_LSN *lsn, int id, u_int32_t flags);
        static void _stream_error_function(const DB_ENV *env,
            const char *prefix, const char *message);
        static void _stream_message_function(const DB_ENV *env,
            const char *message);
        static void _thread_id_intercept(DB_ENV *env, pid_t *pidp,
            db_threadid_t *thridp);
        static char *_thread_id_string_intercept(DB_ENV *env, pid_t pid,
            db_threadid_t thrid, char *buf);

private:
        void cleanup();
        int initialize(DB_ENV *env);
        int error_policy();

        // For internal use only.
        DbEnv(DB_ENV *, u_int32_t flags);

        // no copying
        DbEnv(const DbEnv &);
        void operator = (const DbEnv &);

        // instance data
        DB_ENV *imp_;
        int construct_error_;
        u_int32_t construct_flags_;
        __DB_STD(ostream) *error_stream_;
        __DB_STD(ostream) *message_stream_;

        int (*app_dispatch_callback_)(DbEnv *, Dbt *, DbLsn *, db_recops);
        int (*isalive_callback_)(DbEnv *, pid_t, db_threadid_t);
        void (*error_callback_)(const DbEnv *, const char *, const char *);
        void (*feedback_callback_)(DbEnv *, int, int);
        void (*message_callback_)(const DbEnv *, const char *);
        void (*paniccall_callback_)(DbEnv *, int);
        int (*rep_send_callback_)(DbEnv *, const Dbt *, const Dbt *,
            const DbLsn *, int, u_int32_t);
        void (*thread_id_callback_)(DbEnv *, pid_t *, db_threadid_t *);
        char *(*thread_id_string_callback_)(DbEnv *, pid_t, db_threadid_t,
            char *);
};

//
// Lock
//
class _exported DbLock
{
        friend class DbEnv;

public:
        DbLock();
        DbLock(const DbLock &);
        DbLock &operator = (const DbLock &);

protected:
        // We can add data to this class if needed
        // since its contained class is not allocated by db.
        // (see comment at top)

        DbLock(DB_LOCK);
        DB_LOCK lock_;
};

//
// Log cursor
//
class _exported DbLogc : protected DB_LOGC
{
        friend class DbEnv;

public:
        int close(u_int32_t _flags);
        int get(DbLsn *lsn, Dbt *data, u_int32_t _flags);

private:
        // No data is permitted in this class (see comment at top)

        // Note: use Db::cursor() to get pointers to a Dbc,
        // and call Dbc::close() rather than delete to release them.
        //
        DbLogc();
        ~DbLogc();

        // no copying
        DbLogc(const Dbc &);
        DbLogc &operator = (const Dbc &);
};

//
// Log sequence number
//
class _exported DbLsn : public DB_LSN
{
        friend class DbEnv;          // friendship needed to cast to base class
        friend class DbLogc;         // friendship needed to cast to base class
};

//
// Memory pool file
//
class _exported DbMpoolFile
{
        friend class DbEnv;
        friend class Db;

public:
        int close(u_int32_t flags);
        int get(db_pgno_t *pgnoaddr, u_int32_t flags, void *pagep);
        int open(const char *file, u_int32_t flags, int mode, size_t pagesize);
        int get_transactional(void);
        int put(void *pgaddr, u_int32_t flags);
        int set(void *pgaddr, u_int32_t flags);
        int get_clear_len(u_int32_t *len);
        int set_clear_len(u_int32_t len);
        int get_fileid(u_int8_t *fileid);
        int set_fileid(u_int8_t *fileid);
        int get_flags(u_int32_t *flagsp);
        int set_flags(u_int32_t flags, int onoff);
        int get_ftype(int *ftype);
        int set_ftype(int ftype);
        int get_lsn_offset(int32_t *offsetp);
        int set_lsn_offset(int32_t offset);
        int get_maxsize(u_int32_t *gbytes, u_int32_t *bytes);
        int set_maxsize(u_int32_t gbytes, u_int32_t bytes);
        int get_pgcookie(DBT *dbt);
        int set_pgcookie(DBT *dbt);
        int get_priority(DB_CACHE_PRIORITY *priorityp);
        int set_priority(DB_CACHE_PRIORITY priority);
        int sync();

        virtual DB_MPOOLFILE *get_DB_MPOOLFILE()
        {
                return imp_;
        }

        virtual const DB_MPOOLFILE *get_const_DB_MPOOLFILE() const
        {
                return imp_;
        }

private:
        DB_MPOOLFILE *imp_;

        // We can add data to this class if needed
        // since it is implemented via a pointer.
        // (see comment at top)

        // Note: use DbEnv::memp_fcreate() to get pointers to a DbMpoolFile,
        // and call DbMpoolFile::close() rather than delete to release them.
        //
        DbMpoolFile();

        // Shut g++ up.
protected:
        virtual ~DbMpoolFile();

private:
        // no copying
        DbMpoolFile(const DbMpoolFile &);
        void operator = (const DbMpoolFile &);
};

//
// This is filled in and returned by the DbEnv::txn_recover() method.
//
class _exported DbPreplist
{
public:
        DbTxn *txn;
        u_int8_t gid[DB_XIDDATASIZE];
};

//
// A sequence record in a database
//
class _exported DbSequence
{
public:
        DbSequence(Db *db, u_int32_t flags);
        virtual ~DbSequence();

        int open(DbTxn *txnid, Dbt *key, u_int32_t flags);
        int initial_value(db_seq_t value);
        int close(u_int32_t flags);
        int remove(DbTxn *txnid, u_int32_t flags);
        int stat(DB_SEQUENCE_STAT **sp, u_int32_t flags);
        int stat_print(u_int32_t flags);

        int get(DbTxn *txnid, int32_t delta, db_seq_t *retp, u_int32_t flags);
        int get_cachesize(int32_t *sizep);
        int set_cachesize(int32_t size);
        int get_flags(u_int32_t *flagsp);
        int set_flags(u_int32_t flags);
        int get_range(db_seq_t *minp, db_seq_t *maxp);
        int set_range(db_seq_t min, db_seq_t max);

        Db *get_db();
        Dbt *get_key();

        virtual DB_SEQUENCE *get_DB_SEQUENCE()
        {
                return imp_;
        }

        virtual const DB_SEQUENCE *get_const_DB_SEQUENCE() const
        {
                return imp_;
        }

        static DbSequence* get_DbSequence(DB_SEQUENCE *seq)
        {
                return (DbSequence *)seq->api_internal;
        }

        static const DbSequence* get_const_DbSequence(const DB_SEQUENCE *seq)
        {
                return (const DbSequence *)seq->api_internal;
        }

        // For internal use only.
        static DbSequence* wrap_DB_SEQUENCE(DB_SEQUENCE *seq);

private:
        DbSequence(DB_SEQUENCE *seq);
        // no copying
        DbSequence(const DbSequence &);
        DbSequence &operator = (const DbSequence &);

        DB_SEQUENCE *imp_;
        DBT key_;
};

//
// Transaction
//
class _exported DbTxn
{
        friend class DbEnv;

public:
        int abort();
        int commit(u_int32_t flags);
        int discard(u_int32_t flags);
        u_int32_t id();
        int get_name(const char **namep);
        int prepare(u_int8_t *gid);
        int set_name(const char *name);
        int set_timeout(db_timeout_t timeout, u_int32_t flags);

        virtual DB_TXN *get_DB_TXN()
        {
                return imp_;
        }

        virtual const DB_TXN *get_const_DB_TXN() const
        {
                return imp_;
        }

        static DbTxn* get_DbTxn(DB_TXN *txn)
        {
                return (DbTxn *)txn->api_internal;
        }

        static const DbTxn* get_const_DbTxn(const DB_TXN *txn)
        {
                return (const DbTxn *)txn->api_internal;
        }

        // For internal use only.
        static DbTxn* wrap_DB_TXN(DB_TXN *txn);

private:
        DB_TXN *imp_;

        // We can add data to this class if needed
        // since it is implemented via a pointer.
        // (see comment at top)

        // Note: use DbEnv::txn_begin() to get pointers to a DbTxn,
        // and call DbTxn::abort() or DbTxn::commit rather than
        // delete to release them.
        //
        DbTxn();
        // For internal use only.
        DbTxn(DB_TXN *txn);
        virtual ~DbTxn();

        // no copying
        DbTxn(const DbTxn &);
        void operator = (const DbTxn &);
};

//
// A chunk of data, maybe a key or value.
//
class _exported Dbt : private DBT
{
        friend class Db;
        friend class Dbc;
        friend class DbEnv;
        friend class DbLogc;
        friend class DbSequence;

public:
        // key/data
        void *get_data() const                 { return data; }
        void set_data(void *value)             { data = value; }

        // key/data length
        u_int32_t get_size() const             { return size; }
        void set_size(u_int32_t value)         { size = value; }

        // RO: length of user buffer.
        u_int32_t get_ulen() const             { return ulen; }
        void set_ulen(u_int32_t value)         { ulen = value; }

        // RO: get/put record length.
        u_int32_t get_dlen() const             { return dlen; }
        void set_dlen(u_int32_t value)         { dlen = value; }

        // RO: get/put record offset.
        u_int32_t get_doff() const             { return doff; }
        void set_doff(u_int32_t value)         { doff = value; }

        // flags
        u_int32_t get_flags() const            { return flags; }
        void set_flags(u_int32_t value)        { flags = value; }

        // Conversion functions
        DBT *get_DBT()                         { return (DBT *)this; }
        const DBT *get_const_DBT() const       { return (const DBT *)this; }

        static Dbt* get_Dbt(DBT *dbt)          { return (Dbt *)dbt; }
        static const Dbt* get_const_Dbt(const DBT *dbt)
                                               { return (const Dbt *)dbt; }

        Dbt(void *data, u_int32_t size);
        Dbt();
        ~Dbt();
        Dbt(const Dbt &);
        Dbt &operator = (const Dbt &);

private:
        // Note: no extra data appears in this class (other than
        // inherited from DBT) since we need DBT and Dbt objects
        // to have interchangable pointers.
        //
        // When subclassing this class, remember that callback
        // methods like bt_compare, bt_prefix, dup_compare may
        // internally manufacture DBT objects (which later are
        // cast to Dbt), so such callbacks might receive objects
        // not of your subclassed type.
};

//
// multiple key/data/reco iterator classes
//

// DbMultipleIterator is a shared private base class for the three types
// of bulk-return Iterator;  it should never be instantiated directly,
// but it handles the functionality shared by its subclasses.
class _exported DbMultipleIterator
{
public:
        DbMultipleIterator(const Dbt &dbt);
protected:
        u_int8_t *data_;
        u_int32_t *p_;
};

class _exported DbMultipleKeyDataIterator : private DbMultipleIterator
{
public:
        DbMultipleKeyDataIterator(const Dbt &dbt) : DbMultipleIterator(dbt) {}
        bool next(Dbt &key, Dbt &data);
};

class _exported DbMultipleRecnoDataIterator : private DbMultipleIterator
{
public:
        DbMultipleRecnoDataIterator(const Dbt &dbt) : DbMultipleIterator(dbt) {}
        bool next(db_recno_t &recno, Dbt &data);
};

class _exported DbMultipleDataIterator : private DbMultipleIterator
{
public:
        DbMultipleDataIterator(const Dbt &dbt) : DbMultipleIterator(dbt) {}
        bool next(Dbt &data);
};

//
// Exception classes
//

// Almost any error in the DB library throws a DbException.
// Every exception should be considered an abnormality
// (e.g. bug, misuse of DB, file system error).
//
class _exported DbException : public __DB_STD(exception)
{
public:
        virtual ~DbException() throw();
        DbException(int err);
        DbException(const char *description);
        DbException(const char *description, int err);
        DbException(const char *prefix, const char *description, int err);
        int get_errno() const;
        virtual const char *what() const throw();
        DbEnv *get_env() const;
        void set_env(DbEnv *env);

        DbException(const DbException &);
        DbException &operator = (const DbException &);

private:
        void describe(const char *prefix, const char *description);

        char *what_;
        int err_;                   // errno
        DbEnv *env_;
};

//
// A specific sort of exception that occurs when
// an operation is aborted to resolve a deadlock.
//
class _exported DbDeadlockException : public DbException
{
public:
        virtual ~DbDeadlockException() throw();
        DbDeadlockException(const char *description);

        DbDeadlockException(const DbDeadlockException &);
        DbDeadlockException &operator = (const DbDeadlockException &);
};

//
// A specific sort of exception that occurs when
// a lock is not granted, e.g. by lock_get or lock_vec.
// Note that the Dbt is only live as long as the Dbt used
// in the offending call.
//
class _exported DbLockNotGrantedException : public DbException
{
public:
        virtual ~DbLockNotGrantedException() throw();
        DbLockNotGrantedException(const char *prefix, db_lockop_t op,
            db_lockmode_t mode, const Dbt *obj, const DbLock lock, int index);
        DbLockNotGrantedException(const char *description);

        DbLockNotGrantedException(const DbLockNotGrantedException &);
        DbLockNotGrantedException &operator =
            (const DbLockNotGrantedException &);

        db_lockop_t get_op() const;
        db_lockmode_t get_mode() const;
        const Dbt* get_obj() const;
        DbLock *get_lock() const;
        int get_index() const;

private:
        db_lockop_t op_;
        db_lockmode_t mode_;
        const Dbt *obj_;
        DbLock *lock_;
        int index_;
};

//
// A specific sort of exception that occurs when
// user declared memory is insufficient in a Dbt.
//
class _exported DbMemoryException : public DbException
{
public:
        virtual ~DbMemoryException() throw();
        DbMemoryException(Dbt *dbt);
        DbMemoryException(const char *prefix, Dbt *dbt);

        DbMemoryException(const DbMemoryException &);
        DbMemoryException &operator = (const DbMemoryException &);

        Dbt *get_dbt() const;
private:
        Dbt *dbt_;
};

//
// A specific sort of exception that occurs when a change of replication
// master requires that all handles be re-opened.
//
class _exported DbRepHandleDeadException : public DbException
{
public:
        virtual ~DbRepHandleDeadException() throw();
        DbRepHandleDeadException(const char *description);

        DbRepHandleDeadException(const DbRepHandleDeadException &);
        DbRepHandleDeadException &operator = (const DbRepHandleDeadException &);
};

//
// A specific sort of exception that occurs when
// recovery is required before continuing DB activity.
//
class _exported DbRunRecoveryException : public DbException
{
public:
        virtual ~DbRunRecoveryException() throw();
        DbRunRecoveryException(const char *description);

        DbRunRecoveryException(const DbRunRecoveryException &);
        DbRunRecoveryException &operator = (const DbRunRecoveryException &);
};
#endif /* !_DB_CXX_H_ */

---