rpm/db/examples_cxx/EnvExample.cpp

123 lines
2.7 KiB
C++

/*-
* See the file LICENSE for redistribution information.
*
* Copyright (c) 1997, 1998, 1999, 2000
* Sleepycat Software. All rights reserved.
*
* $Id: EnvExample.cpp,v 11.12 2000/10/27 20:32:00 dda Exp $
*/
#include "db_config.h"
#ifndef NO_SYSTEM_INCLUDES
#include <sys/types.h>
#include <errno.h>
#include <iostream.h>
#include <stddef.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#endif
#include <db_cxx.h>
#ifdef macintosh
#define DATABASE_HOME ":database"
#define CONFIG_DATA_DIR ":database"
#else
#ifdef DB_WIN32
#define DATABASE_HOME "\\tmp\\database"
#define CONFIG_DATA_DIR "\\database\\files"
#else
#define DATABASE_HOME "/tmp/database"
#define CONFIG_DATA_DIR "/database/files"
#endif
#endif
void db_setup(char *, char *, ostream&);
void db_teardown(char *, char *, ostream&);
char *progname = "EnvExample"; /* Program name. */
//
// An example of a program creating/configuring a Berkeley DB environment.
//
int
main(int, char **)
{
//
// Note: it may be easiest to put all Berkeley DB operations in a
// try block, as seen here. Alternatively, you can change the
// ErrorModel in the DbEnv so that exceptions are never thrown
// and check error returns from all methods.
//
try {
char *data_dir, *home;
//
// All of the shared database files live in /home/database,
// but data files live in /database.
//
home = DATABASE_HOME;
data_dir = CONFIG_DATA_DIR;
cout << "Setup env\n";
db_setup(DATABASE_HOME, data_dir, cerr);
cout << "Teardown env\n";
db_teardown(DATABASE_HOME, data_dir, cerr);
return 0;
}
catch (DbException &dbe) {
cerr << "AccessExample: " << dbe.what() << "\n";
return 1;
}
}
// Note that any of the db calls can throw DbException
void
db_setup(char *home, char *data_dir, ostream& err_stream)
{
//
// Create an environment object and initialize it for error
// reporting.
//
DbEnv *dbenv = new DbEnv(0);
dbenv->set_error_stream(&err_stream);
dbenv->set_errpfx(progname);
//
// We want to specify the shared memory buffer pool cachesize,
// but everything else is the default.
//
dbenv->set_cachesize(0, 64 * 1024, 0);
// Databases are in a subdirectory.
(void)dbenv->set_data_dir(data_dir);
// Open the environment with full transactional support.
dbenv->open(DATABASE_HOME,
DB_CREATE | DB_INIT_LOCK | DB_INIT_LOG | DB_INIT_MPOOL | DB_INIT_TXN, 0);
// Do something interesting...
// Close the handle.
dbenv->close(0);
}
void
db_teardown(char *home, char *data_dir, ostream& err_stream)
{
// Remove the shared database regions.
DbEnv *dbenv = new DbEnv(0);
dbenv->set_error_stream(&err_stream);
dbenv->set_errpfx(progname);
(void)dbenv->set_data_dir(data_dir);
dbenv->remove(home, 0);
delete dbenv;
}