Import BSDDB 4.7.25 (as of svn r89086)
This commit is contained in:
Zachary Ware
202
examples_c/ex_btrec.c
Normal file
202
examples_c/ex_btrec.c
Normal file
@@ -0,0 +1,202 @@
|
||||
/*-
|
||||
* See the file LICENSE for redistribution information.
|
||||
*
|
||||
* Copyright (c) 1997,2008 Oracle. All rights reserved.
|
||||
*
|
||||
* $Id: ex_btrec.c 63573 2008-05-23 21:43:21Z trent.nelson $
|
||||
*/
|
||||
|
||||
#include <sys/types.h>
|
||||
|
||||
#include <errno.h>
|
||||
#include <stdlib.h>
|
||||
#include <string.h>
|
||||
|
||||
#include <db.h>
|
||||
|
||||
#define DATABASE "access.db"
|
||||
#define WORDLIST "../test/wordlist"
|
||||
int main __P((void));
|
||||
|
||||
int ex_btrec __P((void));
|
||||
void show __P((const char *, DBT *, DBT *));
|
||||
|
||||
int
|
||||
main()
|
||||
{
|
||||
return (ex_btrec() == 1 ? EXIT_FAILURE : EXIT_SUCCESS);
|
||||
}
|
||||
|
||||
int
|
||||
ex_btrec()
|
||||
{
|
||||
DB *dbp;
|
||||
DBC *dbcp;
|
||||
DBT key, data;
|
||||
DB_BTREE_STAT *statp;
|
||||
FILE *fp;
|
||||
db_recno_t recno;
|
||||
size_t len;
|
||||
int cnt, ret;
|
||||
char *p, *t, buf[1024], rbuf[1024];
|
||||
const char *progname = "ex_btrec"; /* Program name. */
|
||||
|
||||
/* Open the word database. */
|
||||
if ((fp = fopen(WORDLIST, "r")) == NULL) {
|
||||
fprintf(stderr, "%s: open %s: %s\n",
|
||||
progname, WORDLIST, db_strerror(errno));
|
||||
return (1);
|
||||
}
|
||||
|
||||
/* Remove the previous database. */
|
||||
(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 (1);
|
||||
}
|
||||
dbp->set_errfile(dbp, stderr);
|
||||
dbp->set_errpfx(dbp, progname); /* 1K page sizes. */
|
||||
if ((ret = dbp->set_pagesize(dbp, 1024)) != 0) {
|
||||
dbp->err(dbp, ret, "set_pagesize");
|
||||
return (1);
|
||||
} /* Record numbers. */
|
||||
if ((ret = dbp->set_flags(dbp, DB_RECNUM)) != 0) {
|
||||
dbp->err(dbp, ret, "set_flags: DB_RECNUM");
|
||||
return (1);
|
||||
}
|
||||
if ((ret = dbp->open(dbp,
|
||||
NULL, DATABASE, NULL, DB_BTREE, DB_CREATE, 0664)) != 0) {
|
||||
dbp->err(dbp, ret, "open: %s", DATABASE);
|
||||
return (1);
|
||||
}
|
||||
|
||||
/*
|
||||
* Insert records into the database, where the key is the word
|
||||
* preceded by its record number, and the data is the same, but
|
||||
* in reverse order.
|
||||
*/
|
||||
memset(&key, 0, sizeof(DBT));
|
||||
memset(&data, 0, sizeof(DBT));
|
||||
for (cnt = 1; cnt <= 1000; ++cnt) {
|
||||
(void)sprintf(buf, "%04d_", cnt);
|
||||
if (fgets(buf + 4, sizeof(buf) - 4, fp) == NULL)
|
||||
break;
|
||||
len = strlen(buf);
|
||||
for (t = rbuf, p = buf + (len - 2); p >= buf;)
|
||||
*t++ = *p--;
|
||||
*t++ = '\0';
|
||||
|
||||
key.data = buf;
|
||||
data.data = rbuf;
|
||||
data.size = key.size = (u_int32_t)len - 1;
|
||||
|
||||
if ((ret =
|
||||
dbp->put(dbp, NULL, &key, &data, DB_NOOVERWRITE)) != 0) {
|
||||
dbp->err(dbp, ret, "DB->put");
|
||||
if (ret != DB_KEYEXIST)
|
||||
goto err1;
|
||||
}
|
||||
}
|
||||
|
||||
/* Close the word database. */
|
||||
(void)fclose(fp);
|
||||
|
||||
/* Print out the number of records in the database. */
|
||||
if ((ret = dbp->stat(dbp, NULL, &statp, 0)) != 0) {
|
||||
dbp->err(dbp, ret, "DB->stat");
|
||||
goto err1;
|
||||
}
|
||||
printf("%s: database contains %lu records\n",
|
||||
progname, (u_long)statp->bt_ndata);
|
||||
free(statp);
|
||||
|
||||
/* Acquire a cursor for the database. */
|
||||
if ((ret = dbp->cursor(dbp, NULL, &dbcp, 0)) != 0) {
|
||||
dbp->err(dbp, ret, "DB->cursor");
|
||||
goto err1;
|
||||
}
|
||||
|
||||
/*
|
||||
* Prompt the user for a record number, then retrieve and display
|
||||
* that record.
|
||||
*/
|
||||
for (;;) {
|
||||
/* Get a record number. */
|
||||
printf("recno #> ");
|
||||
fflush(stdout);
|
||||
if (fgets(buf, sizeof(buf), stdin) == NULL)
|
||||
break;
|
||||
recno = atoi(buf);
|
||||
|
||||
/*
|
||||
* Reset the key each time, the dbp->get() routine returns
|
||||
* the key and data pair, not just the key!
|
||||
*/
|
||||
key.data = &recno;
|
||||
key.size = sizeof(recno);
|
||||
if ((ret = dbcp->get(dbcp, &key, &data, DB_SET_RECNO)) != 0)
|
||||
goto get_err;
|
||||
|
||||
/* Display the key and data. */
|
||||
show("k/d\t", &key, &data);
|
||||
|
||||
/* Move the cursor a record forward. */
|
||||
if ((ret = dbcp->get(dbcp, &key, &data, DB_NEXT)) != 0)
|
||||
goto get_err;
|
||||
|
||||
/* Display the key and data. */
|
||||
show("next\t", &key, &data);
|
||||
|
||||
/*
|
||||
* Retrieve the record number for the following record into
|
||||
* local memory.
|
||||
*/
|
||||
data.data = &recno;
|
||||
data.size = sizeof(recno);
|
||||
data.ulen = sizeof(recno);
|
||||
data.flags |= DB_DBT_USERMEM;
|
||||
if ((ret = dbcp->get(dbcp, &key, &data, DB_GET_RECNO)) != 0) {
|
||||
get_err: dbp->err(dbp, ret, "DBcursor->get");
|
||||
if (ret != DB_NOTFOUND && ret != DB_KEYEMPTY)
|
||||
goto err2;
|
||||
} else
|
||||
printf("retrieved recno: %lu\n", (u_long)recno);
|
||||
|
||||
/* Reset the data DBT. */
|
||||
memset(&data, 0, sizeof(data));
|
||||
}
|
||||
|
||||
if ((ret = dbcp->close(dbcp)) != 0) {
|
||||
dbp->err(dbp, ret, "DBcursor->close");
|
||||
goto err1;
|
||||
}
|
||||
if ((ret = dbp->close(dbp, 0)) != 0) {
|
||||
fprintf(stderr,
|
||||
"%s: DB->close: %s\n", progname, db_strerror(ret));
|
||||
return (1);
|
||||
}
|
||||
|
||||
return (0);
|
||||
|
||||
err2: (void)dbcp->close(dbcp);
|
||||
err1: (void)dbp->close(dbp, 0);
|
||||
return (ret);
|
||||
|
||||
}
|
||||
|
||||
/*
|
||||
* show --
|
||||
* Display a key/data pair.
|
||||
*/
|
||||
void
|
||||
show(msg, key, data)
|
||||
const char *msg;
|
||||
DBT *key, *data;
|
||||
{
|
||||
printf("%s%.*s : %.*s\n", msg,
|
||||
(int)key->size, (char *)key->data,
|
||||
(int)data->size, (char *)data->data);
|
||||
}
|
||||
Reference in New Issue
Block a user