libdb/examples/c/ex_sequence.c
2012-11-14 15:13:24 -05:00

132 lines
2.7 KiB
C

/*-
* See the file LICENSE for redistribution information.
*
* Copyright (c) 1997, 2012 Oracle and/or its affiliates. All rights reserved.
*
* $Id$
*/
#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 ch, i, ret, rflag;
db_seq_t seqnum;
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 %I64d\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);
}