1/* reps-table.c : operations on the `representations' table
2 *
3 * ====================================================================
4 *    Licensed to the Apache Software Foundation (ASF) under one
5 *    or more contributor license agreements.  See the NOTICE file
6 *    distributed with this work for additional information
7 *    regarding copyright ownership.  The ASF licenses this file
8 *    to you under the Apache License, Version 2.0 (the
9 *    "License"); you may not use this file except in compliance
10 *    with the License.  You may obtain a copy of the License at
11 *
12 *      http://www.apache.org/licenses/LICENSE-2.0
13 *
14 *    Unless required by applicable law or agreed to in writing,
15 *    software distributed under the License is distributed on an
16 *    "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
17 *    KIND, either express or implied.  See the License for the
18 *    specific language governing permissions and limitations
19 *    under the License.
20 * ====================================================================
21 */
22
23#include "bdb_compat.h"
24#include "svn_fs.h"
25#include "../fs.h"
26#include "../util/fs_skels.h"
27#include "../err.h"
28#include "dbt.h"
29#include "../trail.h"
30#include "../key-gen.h"
31#include "../../libsvn_fs/fs-loader.h"
32#include "bdb-err.h"
33#include "reps-table.h"
34#include "strings-table.h"
35
36
37#include "svn_private_config.h"
38
39
40/*** Creating and opening the representations table. ***/
41
42int
43svn_fs_bdb__open_reps_table(DB **reps_p,
44                            DB_ENV *env,
45                            svn_boolean_t create)
46{
47  const u_int32_t open_flags = (create ? (DB_CREATE | DB_EXCL) : 0);
48  DB *reps;
49
50  BDB_ERR(svn_fs_bdb__check_version());
51  BDB_ERR(db_create(&reps, env, 0));
52  BDB_ERR((reps->open)(SVN_BDB_OPEN_PARAMS(reps, NULL),
53                       "representations", 0, DB_BTREE,
54                       open_flags, 0666));
55
56  /* Create the `next-key' table entry.  */
57  if (create)
58  {
59    DBT key, value;
60
61    BDB_ERR(reps->put
62            (reps, 0,
63             svn_fs_base__str_to_dbt(&key, NEXT_KEY_KEY),
64             svn_fs_base__str_to_dbt(&value, "0"), 0));
65  }
66
67  *reps_p = reps;
68  return 0;
69}
70
71
72
73/*** Storing and retrieving reps.  ***/
74
75svn_error_t *
76svn_fs_bdb__read_rep(representation_t **rep_p,
77                     svn_fs_t *fs,
78                     const char *key,
79                     trail_t *trail,
80                     apr_pool_t *pool)
81{
82  base_fs_data_t *bfd = fs->fsap_data;
83  svn_skel_t *skel;
84  int db_err;
85  DBT query, result;
86
87  svn_fs_base__trail_debug(trail, "representations", "get");
88  db_err = bfd->representations->get(bfd->representations,
89                                     trail->db_txn,
90                                     svn_fs_base__str_to_dbt(&query, key),
91                                     svn_fs_base__result_dbt(&result), 0);
92  svn_fs_base__track_dbt(&result, pool);
93
94  /* If there's no such node, return an appropriately specific error.  */
95  if (db_err == DB_NOTFOUND)
96    return svn_error_createf
97      (SVN_ERR_FS_NO_SUCH_REPRESENTATION, 0,
98       _("No such representation '%s'"), key);
99
100  /* Handle any other error conditions.  */
101  SVN_ERR(BDB_WRAP(fs, N_("reading representation"), db_err));
102
103  /* Parse the REPRESENTATION skel.  */
104  skel = svn_skel__parse(result.data, result.size, pool);
105
106  /* Convert to a native type.  */
107  return svn_fs_base__parse_representation_skel(rep_p, skel, pool);
108}
109
110
111svn_error_t *
112svn_fs_bdb__write_rep(svn_fs_t *fs,
113                      const char *key,
114                      const representation_t *rep,
115                      trail_t *trail,
116                      apr_pool_t *pool)
117{
118  base_fs_data_t *bfd = fs->fsap_data;
119  DBT query, result;
120  svn_skel_t *skel;
121
122  /* Convert from native type to skel. */
123  SVN_ERR(svn_fs_base__unparse_representation_skel(&skel, rep,
124                                                   bfd->format, pool));
125
126  /* Now write the record. */
127  svn_fs_base__trail_debug(trail, "representations", "put");
128  return BDB_WRAP(fs, N_("storing representation"),
129                  bfd->representations->put
130                  (bfd->representations, trail->db_txn,
131                   svn_fs_base__str_to_dbt(&query, key),
132                   svn_fs_base__skel_to_dbt(&result, skel, pool),
133                   0));
134}
135
136
137svn_error_t *
138svn_fs_bdb__write_new_rep(const char **key,
139                          svn_fs_t *fs,
140                          const representation_t *rep,
141                          trail_t *trail,
142                          apr_pool_t *pool)
143{
144  base_fs_data_t *bfd = fs->fsap_data;
145  DBT query, result;
146  int db_err;
147  apr_size_t len;
148  char next_key[MAX_KEY_SIZE];
149
150  /* ### todo: see issue #409 for why bumping the key as part of this
151     trail is problematic. */
152
153  /* Get the current value associated with `next-key'.  */
154  svn_fs_base__str_to_dbt(&query, NEXT_KEY_KEY);
155  svn_fs_base__trail_debug(trail, "representations", "get");
156  SVN_ERR(BDB_WRAP(fs, N_("allocating new representation (getting next-key)"),
157                   bfd->representations->get
158                   (bfd->representations, trail->db_txn, &query,
159                    svn_fs_base__result_dbt(&result), 0)));
160
161  svn_fs_base__track_dbt(&result, pool);
162
163  /* Store the new rep. */
164  *key = apr_pstrmemdup(pool, result.data, result.size);
165  SVN_ERR(svn_fs_bdb__write_rep(fs, *key, rep, trail, pool));
166
167  /* Bump to future key. */
168  len = result.size;
169  svn_fs_base__next_key(result.data, &len, next_key);
170  svn_fs_base__trail_debug(trail, "representations", "put");
171  db_err = bfd->representations->put
172    (bfd->representations, trail->db_txn,
173     svn_fs_base__str_to_dbt(&query, NEXT_KEY_KEY),
174     svn_fs_base__str_to_dbt(&result, next_key),
175     0);
176
177  return BDB_WRAP(fs, N_("bumping next representation key"), db_err);
178}
179
180
181svn_error_t *
182svn_fs_bdb__delete_rep(svn_fs_t *fs,
183                       const char *key,
184                       trail_t *trail,
185                       apr_pool_t *pool)
186{
187  base_fs_data_t *bfd = fs->fsap_data;
188  int db_err;
189  DBT query;
190
191  svn_fs_base__trail_debug(trail, "representations", "del");
192  db_err = bfd->representations->del
193    (bfd->representations, trail->db_txn,
194     svn_fs_base__str_to_dbt(&query, key), 0);
195
196  /* If there's no such node, return an appropriately specific error.  */
197  if (db_err == DB_NOTFOUND)
198    return svn_error_createf
199      (SVN_ERR_FS_NO_SUCH_REPRESENTATION, 0,
200       _("No such representation '%s'"), key);
201
202  /* Handle any other error conditions.  */
203  return BDB_WRAP(fs, N_("deleting representation"), db_err);
204}
205