ex_sequence.c

/*-
 * See the file LICENSE for redistribution information.
 *
 * Copyright (c) 1997-2005
 *      Sleepycat Software.  All rights reserved.
 *
 * $Id: ex_sequence.c,v 12.3 2005/11/03 17:46:15 bostic Exp $
 */

#include <sys/types.h>

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#ifdef _WIN32
extern int getopt(int, char * const *, const char *);
#else
#include <unistd.h>
#endif

#include <db.h>

#define DATABASE        "sequence.db"
#define SEQUENCE        "my_sequence"
int main __P((int, char *[]));
int usage __P((void));

int
main(argc, argv)
        int argc;
        char *argv[];
{
        extern int optind;
        DB *dbp;
        DB_SEQUENCE *seq;
        DBT key;
        int i, ret, rflag;
        db_seq_t seqnum;
        char ch;
        const char *database, *progname = "ex_sequence";

        dbp = NULL;
        seq = NULL;

        rflag = 0;
        while ((ch = getopt(argc, argv, "r")) != EOF)
                switch (ch) {
                case 'r':
                        rflag = 1;
                        break;
                case '?':
                default:
                        return (usage());
                }
        argc -= optind;
        argv += optind;

        /* Accept optional database name. */
        database = *argv == NULL ? DATABASE : argv[0];

        /* Optionally discard the database. */
        if (rflag)
                (void)remove(database);

        /* Create and initialize database object, open the database. */
        if ((ret = db_create(&dbp, NULL, 0)) != 0) {
                fprintf(stderr,
                    "%s: db_create: %s\n", progname, db_strerror(ret));
                return (EXIT_FAILURE);
        }
        dbp->set_errfile(dbp, stderr);
        dbp->set_errpfx(dbp, progname);
        if ((ret = dbp->open(dbp,
            NULL, database, NULL, DB_BTREE, DB_CREATE, 0664)) != 0) {
                dbp->err(dbp, ret, "%s: open", database);
                goto err;
        }

        if ((ret = db_sequence_create(&seq, dbp, 0)) != 0) {
                dbp->err(dbp, ret, "db_sequence_create");
                goto err;
        }

        memset(&key, 0, sizeof(DBT));
        key.data = SEQUENCE;
        key.size = (u_int32_t)strlen(SEQUENCE);

        if ((ret = seq->open(seq, NULL, &key, DB_CREATE)) != 0) {
                dbp->err(dbp, ret, "%s: DB_SEQUENCE->open", SEQUENCE);
                goto err;
        }

        for (i = 0; i < 10; i++) {
                if ((ret = seq->get(seq, NULL, 1, &seqnum, 0)) != 0) {
                        dbp->err(dbp, ret, "DB_SEQUENCE->get");
                        goto err;
                }

                /* There's no portable way to print 64-bit numbers. */
#ifdef _WIN32
                printf("Got sequence number %l64d\n", (int64_t)seqnum);
#else
                printf(
                    "Got sequence number %llu\n", (unsigned long long)seqnum);
#endif
        }

        /* Close everything down. */
        if ((ret = seq->close(seq, 0)) != 0) {
                seq = NULL;
                dbp->err(dbp, ret, "DB_SEQUENCE->close");
                goto err;
        }
        if ((ret = dbp->close(dbp, 0)) != 0) {
                fprintf(stderr,
                    "%s: DB->close: %s\n", progname, db_strerror(ret));
                return (EXIT_FAILURE);
        }
        return (EXIT_SUCCESS);

err:    if (seq != NULL)
                (void)seq->close(seq, 0);
        if (dbp != NULL)
                (void)dbp->close(dbp, 0);
        return (EXIT_FAILURE);
}

int
usage()
{
        (void)fprintf(stderr, "usage: ex_sequence [-r] [database]\n");
        return (EXIT_FAILURE);
}

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