/* txn-table.c : operations on the `transactions' table
*
* ====================================================================
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
* ====================================================================
*/
#include <string.h>
#include <assert.h>
#include "bdb_compat.h"
#include "svn_pools.h"
#include "private/svn_skel.h"
#include "dbt.h"
#include "../err.h"
#include "../fs.h"
#include "../key-gen.h"
#include "../util/fs_skels.h"
#include "../trail.h"
#include "../../libsvn_fs/fs-loader.h"
#include "bdb-err.h"
#include "txn-table.h"
#include "svn_private_config.h"
static svn_boolean_t
is_committed(transaction_t *txn)
{
return (txn->kind == transaction_kind_committed);
}
int
svn_fs_bdb__open_transactions_table(DB **transactions_p,
DB_ENV *env,
svn_boolean_t create)
{
const u_int32_t open_flags = (create ? (DB_CREATE | DB_EXCL) : 0);
DB *txns;
BDB_ERR(svn_fs_bdb__check_version());
BDB_ERR(db_create(&txns, env, 0));
BDB_ERR((txns->open)(SVN_BDB_OPEN_PARAMS(txns, NULL),
"transactions", 0, DB_BTREE,
open_flags, 0666));
/* Create the `next-key' table entry. */
if (create)
{
DBT key, value;
BDB_ERR(txns->put(txns, 0,
svn_fs_base__str_to_dbt(&key, NEXT_KEY_KEY),
svn_fs_base__str_to_dbt(&value, "0"), 0));
}
*transactions_p = txns;
return 0;
}
svn_error_t *
svn_fs_bdb__put_txn(svn_fs_t *fs,
const transaction_t *txn,
const char *txn_name,
trail_t *trail,
apr_pool_t *pool)
{
base_fs_data_t *bfd = fs->fsap_data;
svn_skel_t *txn_skel;
DBT key, value;
/* Convert native type to skel. */
SVN_ERR(svn_fs_base__unparse_transaction_skel(&txn_skel, txn, pool));
/* Only in the context of this function do we know that the DB call
will not attempt to modify txn_name, so the cast belongs here. */
svn_fs_base__str_to_dbt(&key, txn_name);
svn_fs_base__skel_to_dbt(&value, txn_skel, pool);
svn_fs_base__trail_debug(trail, "transactions", "put");
return BDB_WRAP(fs, N_("storing transaction record"),
bfd->transactions->put(bfd->transactions, trail->db_txn,
&key, &value, 0));
}
/* Allocate a Subversion transaction ID in FS, as part of TRAIL. Set
*ID_P to the new transaction ID, allocated in POOL. */
static svn_error_t *
allocate_txn_id(const char **id_p,
svn_fs_t *fs,
trail_t *trail,
apr_pool_t *pool)
{
base_fs_data_t *bfd = fs->fsap_data;
DBT query, result;
apr_size_t len;
char next_key[MAX_KEY_SIZE];
int db_err;
svn_fs_base__str_to_dbt(&query, NEXT_KEY_KEY);
/* Get the current value associated with the `next-key' key in the table. */
svn_fs_base__trail_debug(trail, "transactions", "get");
SVN_ERR(BDB_WRAP(fs, N_("allocating new transaction ID (getting 'next-key')"),
bfd->transactions->get(bfd->transactions, trail->db_txn,
&query,
svn_fs_base__result_dbt(&result),
0)));
svn_fs_base__track_dbt(&result, pool);
/* Set our return value. */
*id_p = apr_pstrmemdup(pool, result.data, result.size);
/* Bump to future key. */
len = result.size;
svn_fs_base__next_key(result.data, &len, next_key);
svn_fs_base__str_to_dbt(&query, NEXT_KEY_KEY);
svn_fs_base__str_to_dbt(&result, next_key);
svn_fs_base__trail_debug(trail, "transactions", "put");
db_err = bfd->transactions->put(bfd->transactions, trail->db_txn,
&query, &result, 0);
return BDB_WRAP(fs, N_("bumping next transaction key"), db_err);
}
svn_error_t *
svn_fs_bdb__create_txn(const char **txn_name_p,
svn_fs_t *fs,
const svn_fs_id_t *root_id,
trail_t *trail,
apr_pool_t *pool)
{
const char *txn_name;
transaction_t txn;
SVN_ERR(allocate_txn_id(&txn_name, fs, trail, pool));
txn.kind = transaction_kind_normal;
txn.root_id = root_id;
txn.base_id = root_id;
txn.proplist = NULL;
txn.copies = NULL;
txn.revision = SVN_INVALID_REVNUM;
SVN_ERR(svn_fs_bdb__put_txn(fs, &txn, txn_name, trail, pool));
*txn_name_p = txn_name;
return SVN_NO_ERROR;
}
svn_error_t *
svn_fs_bdb__delete_txn(svn_fs_t *fs,
const char *txn_name,
trail_t *trail,
apr_pool_t *pool)
{
base_fs_data_t *bfd = fs->fsap_data;
DBT key;
transaction_t *txn;
/* Make sure TXN is dead. */
SVN_ERR(svn_fs_bdb__get_txn(&txn, fs, txn_name, trail, pool));
if (is_committed(txn))
return svn_fs_base__err_txn_not_mutable(fs, txn_name);
/* Delete the transaction from the `transactions' table. */
svn_fs_base__str_to_dbt(&key, txn_name);
svn_fs_base__trail_debug(trail, "transactions", "del");
return BDB_WRAP(fs, N_("deleting entry from 'transactions' table"),
bfd->transactions->del(bfd->transactions,
trail->db_txn, &key, 0));
}
svn_error_t *
svn_fs_bdb__get_txn(transaction_t **txn_p,
svn_fs_t *fs,
const char *txn_name,
trail_t *trail,
apr_pool_t *pool)
{
base_fs_data_t *bfd = fs->fsap_data;
DBT key, value;
int db_err;
svn_skel_t *skel;
transaction_t *transaction;
/* Only in the context of this function do we know that the DB call
will not attempt to modify txn_name, so the cast belongs here. */
svn_fs_base__trail_debug(trail, "transactions", "get");
db_err = bfd->transactions->get(bfd->transactions, trail->db_txn,
svn_fs_base__str_to_dbt(&key, txn_name),
svn_fs_base__result_dbt(&value),
0);
svn_fs_base__track_dbt(&value, pool);
if (db_err == DB_NOTFOUND)
return svn_fs_base__err_no_such_txn(fs, txn_name);
SVN_ERR(BDB_WRAP(fs, N_("reading transaction"), db_err));
/* Parse TRANSACTION skel */
skel = svn_skel__parse(value.data, value.size, pool);
if (! skel)
return svn_fs_base__err_corrupt_txn(fs, txn_name);
/* Convert skel to native type. */
SVN_ERR(svn_fs_base__parse_transaction_skel(&transaction, skel, pool));
*txn_p = transaction;
return SVN_NO_ERROR;
}
svn_error_t *
svn_fs_bdb__get_txn_list(apr_array_header_t **names_p,
svn_fs_t *fs,
trail_t *trail,
apr_pool_t *pool)
{
base_fs_data_t *bfd = fs->fsap_data;
apr_size_t const next_key_key_len = strlen(NEXT_KEY_KEY);
apr_pool_t *subpool = svn_pool_create(pool);
apr_array_header_t *names;
DBC *cursor;
DBT key, value;
int db_err, db_c_err;
/* Allocate the initial names array */
names = apr_array_make(pool, 4, sizeof(const char *));
/* Create a database cursor to list the transaction names. */
svn_fs_base__trail_debug(trail, "transactions", "cursor");
SVN_ERR(BDB_WRAP(fs, N_("reading transaction list (opening cursor)"),
bfd->transactions->cursor(bfd->transactions,
trail->db_txn, &cursor, 0)));
/* Build a null-terminated array of keys in the transactions table. */
for (db_err = svn_bdb_dbc_get(cursor,
svn_fs_base__result_dbt(&key),
svn_fs_base__result_dbt(&value),
DB_FIRST);
db_err == 0;
db_err = svn_bdb_dbc_get(cursor,
svn_fs_base__result_dbt(&key),
svn_fs_base__result_dbt(&value),
DB_NEXT))
{
transaction_t *txn;
svn_skel_t *txn_skel;
svn_error_t *err;
/* Clear the per-iteration subpool */
svn_pool_clear(subpool);
/* Track the memory alloc'd for fetching the key and value here
so that when the containing pool is cleared, this memory is
freed. */
svn_fs_base__track_dbt(&key, subpool);
svn_fs_base__track_dbt(&value, subpool);
/* Ignore the "next-key" key. */
if (key.size == next_key_key_len
&& 0 == memcmp(key.data, NEXT_KEY_KEY, next_key_key_len))
continue;
/* Parse TRANSACTION skel */
txn_skel = svn_skel__parse(value.data, value.size, subpool);
if (! txn_skel)
{
svn_bdb_dbc_close(cursor);
return svn_fs_base__err_corrupt_txn
(fs, apr_pstrmemdup(pool, key.data, key.size));
}
/* Convert skel to native type. */
if ((err = svn_fs_base__parse_transaction_skel(&txn, txn_skel,
subpool)))
{
svn_bdb_dbc_close(cursor);
return svn_error_trace(err);
}
/* If this is an immutable "committed" transaction, ignore it. */
if (is_committed(txn))
continue;
/* Add the transaction name to the NAMES array, duping it into POOL. */
APR_ARRAY_PUSH(names, const char *) = apr_pstrmemdup(pool, key.data,
key.size);
}
/* Check for errors, but close the cursor first. */
db_c_err = svn_bdb_dbc_close(cursor);
if (db_err != DB_NOTFOUND)
{
SVN_ERR(BDB_WRAP(fs, N_("reading transaction list (listing keys)"),
db_err));
}
SVN_ERR(BDB_WRAP(fs, N_("reading transaction list (closing cursor)"),
db_c_err));
/* Destroy the per-iteration subpool */
svn_pool_destroy(subpool);
*names_p = names;
return SVN_NO_ERROR;
}