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/*-
* See the file LICENSE for redistribution information.
*
* Copyright (c) 1997, 1998
* Sleepycat Software. All rights reserved.
*
* @(#)AccessExample.cpp 10.7 (Sleepycat) 12/7/98
*/
#include "config.h"
#ifndef NO_SYSTEM_INCLUDES
#include <sys/types.h>
#include <iostream.h>
#include <errno.h>
#include <stdlib.h>
#include <string.h>
#ifndef _MSC_VER
#include <unistd.h>
#endif
#endif
#include <db_cxx.h>
class AccessExample : public DbEnv
{
public:
void run();
AccessExample(const char *home);
private:
static const char FileName[];
// no need for copy and assignment
AccessExample(const AccessExample &);
operator = (const AccessExample &);
};
static void usage(); // forward
int main(int argc, char *argv[])
{
const char *home = 0;
for (int i = 1; i < argc; ++i)
{
if (strcmp(argv[i], "-h") == 0)
{
home = argv[++i];
}
else
{
usage();
}
}
try
{
AccessExample app(home);
app.run();
return 0;
}
catch (DbException &dbe)
{
cerr << "AccessExample: " << dbe.what() << "\n";
return 1;
}
}
static void usage()
{
cerr << "usage: AccessExample [-h home]\n";
exit(1);
}
const char AccessExample::FileName[] = "access.db";
AccessExample::AccessExample(const char *home)
: DbEnv(home, 0, 0)
{
set_error_stream(&cerr);
set_errpfx("AccessExample");
}
void AccessExample::run()
{
Db *table;
Db::open(FileName, DB_BTREE, DB_CREATE, 0644, this, 0, &table);
//
// Insert records into the database, where the key is the user
// input and the data is the user input in reverse order.
//
char buf[1024];
char rbuf[1024];
for (;;) {
cout << "input> ";
cout.flush();
cin.getline(buf, sizeof(buf));
if (cin.eof())
break;
int len = strlen(buf);
if (len <= 0)
continue;
char *t = rbuf;
char *p = buf + len - 1;
while (p >= buf)
*t++ = *p--;
*t = '\0';
Dbt key(buf, len+1);
Dbt data(rbuf, len+1);
try
{
int err;
if ((err = table->put(0, &key, &data, 0)) == DB_KEYEXIST) {
cout << "Key " << buf << " already exists.\n";
}
}
catch (DbException &dbe)
{
cout << dbe.what() << "\n";
}
cout << "\n";
}
// Acquire an iterator for the table.
Dbc *iterator;
table->cursor(NULL, &iterator, 0);
// Walk through the table, printing the key/data pairs.
Dbt key;
Dbt data;
while (iterator->get(&key, &data, DB_NEXT) == 0)
{
char *key_string = (char *)key.get_data();
char *data_string = (char *)data.get_data();
cout << key_string << " : " << data_string << "\n";
}
iterator->close();
table->close(0);
}
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