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/*-
* See the file LICENSE for redistribution information.
*
* Copyright (c) 1996-2004
* Sleepycat Software. All rights reserved.
*
* $Id: ex_apprec.c,v 1.5 2004/01/28 03:36:03 bostic Exp $
*/
#include <sys/types.h>
#include <sys/stat.h>
#include <errno.h>
#include <stddef.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <db.h>
#include "ex_apprec.h"
int apprec_dispatch __P((DB_ENV *, DBT *, DB_LSN *, db_recops));
int open_env __P((const char *, FILE *, const char *, DB_ENV **));
int verify_absence __P((DB_ENV *, const char *));
int verify_presence __P((DB_ENV *, const char *));
int
main(argc, argv)
int argc;
char *argv[];
{
extern char *optarg;
DB_ENV *dbenv;
DB_LSN lsn;
DB_TXN *txn;
DBT dirnamedbt;
int ret;
const char *home;
char ch, dirname[256];
const char *progname = "ex_apprec"; /* Program name. */
/* Default home. */
home = "TESTDIR";
while ((ch = getopt(argc, argv, "h:")) != EOF)
switch (ch) {
case 'h':
home = optarg;
break;
default:
fprintf(stderr, "usage: %s [-h home]", progname);
exit(EXIT_FAILURE);
}
printf("Set up environment.\n");
if ((ret = open_env(home, stderr, progname, &dbenv)) != 0)
return (EXIT_FAILURE);
printf("Create a directory in a transaction.\n");
/*
* This application's convention is to log the full directory name,
* including trailing nul.
*/
memset(&dirnamedbt, 0, sizeof(dirnamedbt));
sprintf(dirname, "%s/MYDIRECTORY", home);
dirnamedbt.data = dirname;
dirnamedbt.size = strlen(dirname) + 1;
if ((ret = dbenv->txn_begin(dbenv, NULL, &txn, 0)) != 0) {
dbenv->err(dbenv, ret, "txn_begin");
return (EXIT_FAILURE);
}
/* Remember, always log actions before you execute them! */
memset(&lsn, 0, sizeof(lsn));
if ((ret =
ex_apprec_mkdir_log(dbenv, txn, &lsn, 0, &dirnamedbt)) != 0) {
dbenv->err(dbenv, ret, "mkdir_log");
return (EXIT_FAILURE);
}
if (mkdir(dirname, 0755) != 0) {
dbenv->err(dbenv, errno, "mkdir");
return (EXIT_FAILURE);
}
printf("Verify the directory's presence: ");
verify_presence(dbenv, dirname);
printf("check.\n");
/* Now abort the transaction and verify that the directory goes away. */
printf("Abort the transaction.\n");
if ((ret = txn->abort(txn)) != 0) {
dbenv->err(dbenv, ret, "txn_abort");
return (EXIT_FAILURE);
}
printf("Verify the directory's absence: ");
verify_absence(dbenv, dirname);
printf("check.\n");
/* Now do the same thing over again, only with a commit this time. */
printf("Create a directory in a transaction.\n");
memset(&dirnamedbt, 0, sizeof(dirnamedbt));
sprintf(dirname, "%s/MYDIRECTORY", home);
dirnamedbt.data = dirname;
dirnamedbt.size = strlen(dirname) + 1;
if ((ret = dbenv->txn_begin(dbenv, NULL, &txn, 0)) != 0) {
dbenv->err(dbenv, ret, "txn_begin");
return (EXIT_FAILURE);
}
memset(&lsn, 0, sizeof(lsn));
if ((ret =
ex_apprec_mkdir_log(dbenv, txn, &lsn, 0, &dirnamedbt)) != 0) {
dbenv->err(dbenv, ret, "mkdir_log");
return (EXIT_FAILURE);
}
if (mkdir(dirname, 0755) != 0) {
dbenv->err(dbenv, errno, "mkdir");
return (EXIT_FAILURE);
}
printf("Verify the directory's presence: ");
verify_presence(dbenv, dirname);
printf("check.\n");
/* Now abort the transaction and verify that the directory goes away. */
printf("Commit the transaction.\n");
if ((ret = txn->commit(txn, 0)) != 0) {
dbenv->err(dbenv, ret, "txn_commit");
return (EXIT_FAILURE);
}
printf("Verify the directory's presence: ");
verify_presence(dbenv, dirname);
printf("check.\n");
printf("Now remove the directory, then run recovery.\n");
if ((ret = dbenv->close(dbenv, 0)) != 0) {
fprintf(stderr, "DB_ENV->close: %s\n", db_strerror(ret));
return (EXIT_FAILURE);
}
if (rmdir(dirname) != 0) {
fprintf(stderr,
"%s: rmdir failed with error %s", progname,
strerror(errno));
}
verify_absence(dbenv, dirname);
/* Opening with DB_RECOVER runs recovery. */
if ((ret = open_env(home, stderr, progname, &dbenv)) != 0)
return (EXIT_FAILURE);
printf("Verify the directory's presence: ");
verify_presence(dbenv, dirname);
printf("check.\n");
/* Close the handle. */
if ((ret = dbenv->close(dbenv, 0)) != 0) {
fprintf(stderr, "DB_ENV->close: %s\n", db_strerror(ret));
return (EXIT_FAILURE);
}
return (EXIT_SUCCESS);
}
int
open_env(home, errfp, progname, dbenvp)
const char *home, *progname;
FILE *errfp;
DB_ENV **dbenvp;
{
DB_ENV *dbenv;
int ret;
/*
* Create an environment object and initialize it for error
* reporting.
*/
if ((ret = db_env_create(&dbenv, 0)) != 0) {
fprintf(errfp, "%s: %s\n", progname, db_strerror(ret));
return (ret);
}
dbenv->set_errfile(dbenv, errfp);
dbenv->set_errpfx(dbenv, progname);
/* Set up our custom recovery dispatch function. */
if ((ret = dbenv->set_app_dispatch(dbenv, apprec_dispatch)) != 0) {
dbenv->err(dbenv, ret, "set_app_dispatch");
return (ret);
}
/*
* Open the environment with full transactional support, running
* recovery.
*/
if ((ret =
dbenv->open(dbenv, home, DB_CREATE | DB_RECOVER | DB_INIT_LOCK |
DB_INIT_LOG | DB_INIT_MPOOL | DB_INIT_TXN, 0)) != 0) {
dbenv->err(dbenv, ret, "environment open: %s", home);
dbenv->close(dbenv, 0);
return (ret);
}
*dbenvp = dbenv;
return (0);
}
/*
* Sample application dispatch function to handle user-specified log record
* types.
*/
int
apprec_dispatch(dbenv, dbt, lsn, op)
DB_ENV *dbenv;
DBT *dbt;
DB_LSN *lsn;
db_recops op;
{
u_int32_t rectype;
/* Pull the record type out of the log record. */
memcpy(&rectype, dbt->data, sizeof(rectype));
switch (rectype) {
case DB_ex_apprec_mkdir:
return (ex_apprec_mkdir_recover(dbenv, dbt, lsn, op, NULL));
default:
/*
* We've hit an unexpected, allegedly user-defined record
* type.
*/
dbenv->errx(dbenv, "Unexpected log record type encountered");
return (EINVAL);
}
}
int
verify_absence(dbenv, dirname)
DB_ENV *dbenv;
const char *dirname;
{
if (access(dirname, F_OK) == 0) {
dbenv->errx(dbenv, "Error--directory present!");
exit(EXIT_FAILURE);
}
return (0);
}
int
verify_presence(dbenv, dirname)
DB_ENV *dbenv;
const char *dirname;
{
if (access(dirname, F_OK) != 0) {
dbenv->errx(dbenv, "Error--directory not present!");
exit(EXIT_FAILURE);
}
return (0);
}
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