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/*-
* See the file LICENSE for redistribution information.
*
* Copyright (c) 1997-2001
* Sleepycat Software. All rights reserved.
*
* $Id: db_cxx.h,v 11.65 2001/06/19 18:58:59 dda 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 <iostream.h>
#include <stdarg.h>
#include "db.h"
#include "cxx_common.h"
#include "cxx_except.h"
class Db; // forward
class Dbc; // forward
class DbEnv; // forward
class DbInfo; // forward
class DbLock; // forward
class DbLsn; // forward
class DbMpoolFile; // forward
class Dbt; // forward
class DbTxn; // forward
// These classes are not defined here and should be invisible
// to the user, but some compilers require forward references.
// There is one for each use of the DEFINE_DB_CLASS macro.
class DbImp;
class DbEnvImp;
class DbMpoolFileImp;
class DbTxnImp;
// DEFINE_DB_CLASS defines an imp_ data member and imp() accessor.
// The underlying type is a pointer to an opaque *Imp class, that
// gets converted to the correct implementation class by the implementation.
//
// Since these defines use "private/public" labels, and leave the access
// being "private", we always use these by convention before any data
// members in the private section of a class. Keeping them in the
// private section also emphasizes that they are off limits to user code.
//
#define DEFINE_DB_CLASS(name) \
public: class name##Imp* imp() { return (imp_); } \
public: const class name##Imp* constimp() const { return (imp_); } \
private: class name##Imp* imp_
////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////
//
// 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
// 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);
};
////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////
//
// Lock classes
//
class _exported DbLock
{
friend class DbEnv;
public:
DbLock();
int put(DbEnv *env);
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 classes
//
class _exported DbLsn : protected DB_LSN
{
friend class DbEnv; // friendship needed to cast to base class
};
////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////
//
// Memory pool classes
//
class _exported DbMpoolFile
{
friend class DbEnv;
public:
int close();
int get(db_pgno_t *pgnoaddr, u_int32_t flags, void *pagep);
int put(void *pgaddr, u_int32_t flags);
int set(void *pgaddr, u_int32_t flags);
int sync();
static int open(DbEnv *envp, const char *file,
u_int32_t flags, int mode, size_t pagesize,
DB_MPOOL_FINFO *finfop, DbMpoolFile **mpf);
private:
// We can add data to this class if needed
// since it is implemented via a pointer.
// (see comment at top)
// Note: use DbMpoolFile::open()
// to get pointers to a DbMpoolFile,
// and call DbMpoolFile::close() rather than delete to release them.
//
DbMpoolFile();
// Shut g++ up.
protected:
~DbMpoolFile();
private:
// no copying
DbMpoolFile(const DbMpoolFile &);
void operator = (const DbMpoolFile &);
DEFINE_DB_CLASS(DbMpoolFile);
};
////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////
//
// Transaction classes
//
class _exported DbTxn
{
friend class DbEnv;
public:
int abort();
int commit(u_int32_t flags);
u_int32_t id();
int prepare(u_int8_t *gid);
private:
// 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();
~DbTxn();
// no copying
DbTxn(const DbTxn &);
void operator = (const DbTxn &);
DEFINE_DB_CLASS(DbTxn);
};
//
// 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:
~DbEnv();
// 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);
// These methods match those in the C interface.
//
int close(u_int32_t);
void err(int, const char *, ...);
void errx(const char *, ...);
void *get_app_private() const;
int open(const char *, u_int32_t, int);
int remove(const char *, u_int32_t);
int set_alloc(db_malloc_fcn_type, db_realloc_fcn_type,
db_free_fcn_type);
void set_app_private(void *);
int set_cachesize(u_int32_t, u_int32_t, int);
int set_data_dir(const char *);
void set_errcall(void (*)(const char *, char *));
void set_errfile(FILE *);
void set_errpfx(const char *);
int set_flags(u_int32_t, int);
int set_feedback(void (*)(DbEnv *, int, int));
int set_recovery_init(int (*)(DbEnv *));
int set_lg_bsize(u_int32_t);
int set_lg_dir(const char *);
int set_lg_max(u_int32_t);
int set_lg_regionmax(u_int32_t);
int set_lk_conflicts(u_int8_t *, int);
int set_lk_detect(u_int32_t);
int set_lk_max(u_int32_t);
int set_lk_max_lockers(u_int32_t);
int set_lk_max_locks(u_int32_t);
int set_lk_max_objects(u_int32_t);
int set_mp_mmapsize(size_t);
int set_mutexlocks(int);
static int set_pageyield(int);
int set_paniccall(void (*)(DbEnv *, int));
static int set_panicstate(int);
static int set_region_init(int);
int set_rpc_server(void *, char *, long, long, u_int32_t);
int set_shm_key(long);
int set_tmp_dir(const char *);
static int set_tas_spins(u_int32_t);
int set_tx_max(u_int32_t);
int set_tx_recover(int (*)(DbEnv *, Dbt *, DbLsn *, db_recops));
int set_tx_timestamp(time_t *);
int set_verbose(u_int32_t which, int onoff);
// 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.
//
void set_error_stream(ostream *);
// used internally
static void runtime_error(const char *caller, int err,
int error_policy);
static void runtime_error_dbt(const char *caller, Dbt *dbt,
int error_policy);
// Lock functions
//
int lock_detect(u_int32_t flags, u_int32_t atype, int *aborted);
int lock_get(u_int32_t locker, u_int32_t flags, const Dbt *obj,
db_lockmode_t lock_mode, DbLock *lock);
int lock_id(u_int32_t *idp);
int lock_stat(DB_LOCK_STAT **statp);
int lock_vec(u_int32_t locker, u_int32_t flags, DB_LOCKREQ list[],
int nlist, DB_LOCKREQ **elistp);
// Log functions
//
int log_archive(char **list[], u_int32_t flags);
static int log_compare(const DbLsn *lsn0, const DbLsn *lsn1);
int log_file(DbLsn *lsn, char *namep, size_t len);
int log_flush(const DbLsn *lsn);
int log_get(DbLsn *lsn, Dbt *data, u_int32_t flags);
int log_put(DbLsn *lsn, const Dbt *data, u_int32_t flags);
int log_register(Db *dbp, const char *name);
int log_stat(DB_LOG_STAT **spp);
int log_unregister(Db *dbp);
// Mpool functions
//
int memp_register(int ftype,
pgin_fcn_type pgin_fcn,
pgout_fcn_type pgout_fcn);
int memp_stat(DB_MPOOL_STAT **gsp, DB_MPOOL_FSTAT ***fsp);
int memp_sync(DbLsn *lsn);
int memp_trickle(int pct, int *nwrotep);
// Transaction functions
//
int txn_begin(DbTxn *pid, DbTxn **tid, u_int32_t flags);
int txn_checkpoint(u_int32_t kbyte, u_int32_t min, u_int32_t flags);
int txn_recover(DB_PREPLIST *preplist, long count,
long *retp, u_int32_t flags);
int txn_stat(DB_TXN_STAT **statp);
// Conversion functions
//
DB_ENV *get_DB_ENV()
{
return (DB_ENV *)imp();
}
const DB_ENV *get_const_DB_ENV() const
{
return (const DB_ENV *)constimp();
}
static DbEnv* get_DbEnv(DB_ENV *dbenv)
{
return (DbEnv *)dbenv->cj_internal;
}
static const DbEnv* get_const_DbEnv(const DB_ENV *dbenv)
{
return (const DbEnv *)dbenv->cj_internal;
}
// These are public only because they need to be called
// via C functions. They should never be called by users
// of this class.
//
static void _stream_error_function(const char *, char *);
static int _tx_recover_intercept(DB_ENV *env, DBT *dbt, DB_LSN *lsn,
db_recops op);
static void _paniccall_intercept(DB_ENV *env, int errval);
static int _recovery_init_intercept(DB_ENV *env);
static void _feedback_intercept(DB_ENV *env, int opcode, int pct);
static void _destroy_check(const char *str, int isDbEnv);
private:
void cleanup();
int initialize(DB_ENV *env);
int error_policy();
// Used internally
DbEnv(DB_ENV *, u_int32_t flags);
// no copying
DbEnv(const DbEnv &);
void operator = (const DbEnv &);
DEFINE_DB_CLASS(DbEnv);
// instance data
int construct_error_;
u_int32_t construct_flags_;
int (*tx_recover_callback_)(DbEnv *, Dbt *, DbLsn *, db_recops);
int (*recovery_init_callback_)(DbEnv *);
void (*paniccall_callback_)(DbEnv *, int);
void (*feedback_callback_)(DbEnv *, int, int);
int (*pgin_callback_)(DbEnv *dbenv, db_pgno_t pgno,
void *pgaddr, Dbt *pgcookie);
int (*pgout_callback_)(DbEnv *dbenv, db_pgno_t pgno,
void *pgaddr, Dbt *pgcookie);
// class data
static ostream *error_stream_;
};
////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////
//
// Table access classes
//
//
// 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, then call open()
~Db(); // does *not* call close.
// These methods exactly match those in the C interface.
//
int associate(Db *secondary, int (*callback)(Db *, const Dbt *,
const Dbt *, Dbt *), u_int32_t flags);
int close(u_int32_t flags);
int cursor(DbTxn *txnid, Dbc **cursorp, u_int32_t flags);
int del(DbTxn *txnid, Dbt *key, u_int32_t flags);
void err(int, const char *, ...);
void errx(const char *, ...);
int fd(int *fdp);
int get(DbTxn *txnid, Dbt *key, Dbt *data, u_int32_t flags);
void *get_app_private() const;
int get_byteswapped(int *);
int get_type(DBTYPE *);
int join(Dbc **curslist, Dbc **dbcp, u_int32_t flags);
int key_range(DbTxn *, Dbt *, DB_KEY_RANGE *, u_int32_t);
int open(const char *, const char *subname, DBTYPE, u_int32_t, int);
int pget(DbTxn *txnid, Dbt *key, Dbt *pkey, Dbt *data,
u_int32_t flags);
int put(DbTxn *, Dbt *, Dbt *, u_int32_t);
int remove(const char *, const char *, u_int32_t);
int rename(const char *, const char *, const char *, u_int32_t);
int set_alloc(db_malloc_fcn_type, db_realloc_fcn_type,
db_free_fcn_type);
void set_app_private(void *);
int set_append_recno(int (*)(Db *, Dbt *, db_recno_t));
int set_bt_compare(bt_compare_fcn_type); /*deprecated*/
int set_bt_compare(int (*)(Db *, const Dbt *, const Dbt *));
int set_bt_maxkey(u_int32_t);
int set_bt_minkey(u_int32_t);
int set_bt_prefix(bt_prefix_fcn_type); /*deprecated*/
int set_bt_prefix(size_t (*)(Db *, const Dbt *, const Dbt *));
int set_cachesize(u_int32_t, u_int32_t, int);
int set_dup_compare(dup_compare_fcn_type); /*deprecated*/
int set_dup_compare(int (*)(Db *, const Dbt *, const Dbt *));
void set_errcall(void (*)(const char *, char *));
void set_errfile(FILE *);
void set_errpfx(const char *);
int set_feedback(void (*)(Db *, int, int));
int set_flags(u_int32_t);
int set_h_ffactor(u_int32_t);
int set_h_hash(h_hash_fcn_type); /*deprecated*/
int set_h_hash(u_int32_t (*)(Db *, const void *, u_int32_t));
int set_h_nelem(u_int32_t);
int set_lorder(int);
int set_pagesize(u_int32_t);
int set_paniccall(void (*)(DbEnv *, int));
int set_re_delim(int);
int set_re_len(u_int32_t);
int set_re_pad(int);
int set_re_source(char *);
int set_q_extentsize(u_int32_t);
int stat(void *sp, u_int32_t flags);
int sync(u_int32_t flags);
int truncate(DbTxn *, u_int32_t *, u_int32_t);
int upgrade(const char *name, u_int32_t flags);
int verify(const char *, const char *, ostream *, u_int32_t);
// These additional methods are not in the C interface, and
// are only available for C++.
//
void set_error_stream(ostream *);
DB *get_DB()
{
return (DB *)imp();
}
const DB *get_const_DB() const
{
return (const DB *)constimp();
}
static Db* get_Db(DB *db)
{
return (Db *)db->cj_internal;
}
static const Db* get_const_Db(const DB *db)
{
return (const Db *)db->cj_internal;
}
// 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.
//
void (*feedback_callback_)(Db *, int, int);
int (*append_recno_callback_)(Db *, Dbt *, db_recno_t);
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 *);
u_int32_t (*h_hash_callback_)(Db *, const void *, u_int32_t);
int (*associate_callback_)(Db *, const Dbt *, const Dbt *, Dbt *);
private:
// no copying
Db(const Db &);
Db &operator = (const Db &);
DEFINE_DB_CLASS(Db);
void cleanup();
int initialize();
int error_policy();
// instance data
DbEnv *env_;
int construct_error_;
u_int32_t flags_;
u_int32_t construct_flags_;
};
//
// A chunk of data, maybe a key or value.
//
class _exported Dbt : private DBT
{
friend class Dbc;
friend class Db;
friend class DbEnv;
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, size_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.
};
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 &);
};
#endif /* !_DB_CXX_H_ */
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