1/* nodes-table.c : working with the `nodes' 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 <string.h>
24#include <assert.h>
25
26#include "bdb_compat.h"
27
28#include "svn_fs.h"
29#include "private/svn_skel.h"
30
31#include "../fs.h"
32#include "../err.h"
33#include "dbt.h"
34#include "../util/fs_skels.h"
35#include "../trail.h"
36#include "../key-gen.h"
37#include "../id.h"
38#include "../../libsvn_fs/fs-loader.h"
39#include "bdb-err.h"
40#include "nodes-table.h"
41
42#include "svn_private_config.h"
43
44
45
46/* Opening/creating the `nodes' table.  */
47
48
49int
50svn_fs_bdb__open_nodes_table(DB **nodes_p,
51                             DB_ENV *env,
52                             svn_boolean_t create)
53{
54  const u_int32_t open_flags = (create ? (DB_CREATE | DB_EXCL) : 0);
55  DB *nodes;
56
57  BDB_ERR(svn_fs_bdb__check_version());
58  BDB_ERR(db_create(&nodes, env, 0));
59  BDB_ERR((nodes->open)(SVN_BDB_OPEN_PARAMS(nodes, NULL),
60                        "nodes", 0, DB_BTREE,
61                        open_flags, 0666));
62
63  /* Create the `next-key' table entry (use '1' because '0' is
64     reserved for the root directory to use). */
65  if (create)
66  {
67    DBT key, value;
68
69    BDB_ERR(nodes->put(nodes, 0,
70                       svn_fs_base__str_to_dbt(&key, NEXT_KEY_KEY),
71                       svn_fs_base__str_to_dbt(&value, "1"), 0));
72  }
73
74  *nodes_p = nodes;
75  return 0;
76}
77
78
79
80/* Choosing node revision ID's.  */
81
82svn_error_t *
83svn_fs_bdb__new_node_id(svn_fs_id_t **id_p,
84                        svn_fs_t *fs,
85                        const char *copy_id,
86                        const char *txn_id,
87                        trail_t *trail,
88                        apr_pool_t *pool)
89{
90  base_fs_data_t *bfd = fs->fsap_data;
91  DBT query, result;
92  apr_size_t len;
93  char next_key[MAX_KEY_SIZE];
94  int db_err;
95  const char *next_node_id;
96
97  SVN_ERR_ASSERT(txn_id);
98
99  /* Get the current value associated with the `next-key' key in the table.  */
100  svn_fs_base__str_to_dbt(&query, NEXT_KEY_KEY);
101  svn_fs_base__trail_debug(trail, "nodes", "get");
102  SVN_ERR(BDB_WRAP(fs, N_("allocating new node ID (getting 'next-key')"),
103                   bfd->nodes->get(bfd->nodes, trail->db_txn,
104                                   &query,
105                                   svn_fs_base__result_dbt(&result),
106                                   0)));
107  svn_fs_base__track_dbt(&result, pool);
108
109  /* Squirrel away our next node id value. */
110  next_node_id = apr_pstrmemdup(pool, result.data, result.size);
111
112  /* Bump to future key. */
113  len = result.size;
114  svn_fs_base__next_key(result.data, &len, next_key);
115  svn_fs_base__trail_debug(trail, "nodes", "put");
116  db_err = bfd->nodes->put(bfd->nodes, trail->db_txn,
117                           svn_fs_base__str_to_dbt(&query, NEXT_KEY_KEY),
118                           svn_fs_base__str_to_dbt(&result, next_key),
119                           0);
120  SVN_ERR(BDB_WRAP(fs, N_("bumping next node ID key"), db_err));
121
122  /* Create and return the new node id. */
123  *id_p = svn_fs_base__id_create(next_node_id, copy_id, txn_id, pool);
124  return SVN_NO_ERROR;
125}
126
127
128svn_error_t *
129svn_fs_bdb__new_successor_id(svn_fs_id_t **successor_p,
130                             svn_fs_t *fs,
131                             const svn_fs_id_t *id,
132                             const char *copy_id,
133                             const char *txn_id,
134                             trail_t *trail,
135                             apr_pool_t *pool)
136{
137  svn_fs_id_t *new_id;
138  svn_error_t *err;
139
140  SVN_ERR_ASSERT(txn_id);
141
142  /* Create and return the new successor ID.  */
143  new_id = svn_fs_base__id_create(svn_fs_base__id_node_id(id),
144                                  copy_id ? copy_id
145                                  : svn_fs_base__id_copy_id(id),
146                                  txn_id, pool);
147
148  /* Now, make sure this NEW_ID doesn't already exist in FS. */
149  err = svn_fs_bdb__get_node_revision(NULL, fs, new_id, trail, trail->pool);
150  if ((! err) || (err->apr_err != SVN_ERR_FS_ID_NOT_FOUND))
151    {
152      svn_string_t *id_str = svn_fs_base__id_unparse(id, pool);
153      svn_string_t *new_id_str = svn_fs_base__id_unparse(new_id, pool);
154      return svn_error_createf
155        (SVN_ERR_FS_ALREADY_EXISTS, err,
156         _("Successor id '%s' (for '%s') already exists in filesystem '%s'"),
157         new_id_str->data, id_str->data, fs->path);
158    }
159
160  /* err is SVN_ERR_FS_ID_NOT_FOUND, meaning the ID is available. But
161     we don't want this error. */
162  svn_error_clear(err);
163
164  /* Return the new node revision ID. */
165  *successor_p = new_id;
166  return SVN_NO_ERROR;
167}
168
169
170
171/* Removing node revisions.  */
172svn_error_t *
173svn_fs_bdb__delete_nodes_entry(svn_fs_t *fs,
174                               const svn_fs_id_t *id,
175                               trail_t *trail,
176                               apr_pool_t *pool)
177{
178  base_fs_data_t *bfd = fs->fsap_data;
179  DBT key;
180
181  svn_fs_base__trail_debug(trail, "nodes", "del");
182  return BDB_WRAP(fs, N_("deleting entry from 'nodes' table"),
183                  bfd->nodes->del(bfd->nodes,
184                                  trail->db_txn,
185                                  svn_fs_base__id_to_dbt(&key, id, pool),
186                                  0));
187}
188
189
190
191
192/* Storing and retrieving NODE-REVISIONs.  */
193
194
195svn_error_t *
196svn_fs_bdb__get_node_revision(node_revision_t **noderev_p,
197                              svn_fs_t *fs,
198                              const svn_fs_id_t *id,
199                              trail_t *trail,
200                              apr_pool_t *pool)
201{
202  base_fs_data_t *bfd = fs->fsap_data;
203  node_revision_t *noderev;
204  svn_skel_t *skel;
205  int db_err;
206  DBT key, value;
207
208  svn_fs_base__trail_debug(trail, "nodes", "get");
209  db_err = bfd->nodes->get(bfd->nodes, trail->db_txn,
210                           svn_fs_base__id_to_dbt(&key, id, pool),
211                           svn_fs_base__result_dbt(&value),
212                           0);
213  svn_fs_base__track_dbt(&value, pool);
214
215  /* If there's no such node, return an appropriately specific error.  */
216  if (db_err == DB_NOTFOUND)
217    return svn_fs_base__err_dangling_id(fs, id);
218
219  /* Handle any other error conditions.  */
220  SVN_ERR(BDB_WRAP(fs, N_("reading node revision"), db_err));
221
222  /* If our caller doesn't really care about the return value here,
223     just return successfully. */
224  if (! noderev_p)
225    return SVN_NO_ERROR;
226
227  /* Parse and the NODE-REVISION skel.  */
228  skel = svn_skel__parse(value.data, value.size, pool);
229
230  /* Convert to a native FS type. */
231  SVN_ERR(svn_fs_base__parse_node_revision_skel(&noderev, skel, pool));
232  *noderev_p = noderev;
233  return SVN_NO_ERROR;
234}
235
236
237svn_error_t *
238svn_fs_bdb__put_node_revision(svn_fs_t *fs,
239                              const svn_fs_id_t *id,
240                              node_revision_t *noderev,
241                              trail_t *trail,
242                              apr_pool_t *pool)
243{
244  base_fs_data_t *bfd = fs->fsap_data;
245  DB_TXN *db_txn = trail->db_txn;
246  DBT key, value;
247  svn_skel_t *skel;
248
249  /* Convert from native type into skel */
250  SVN_ERR(svn_fs_base__unparse_node_revision_skel(&skel, noderev,
251                                                  bfd->format, pool));
252  svn_fs_base__trail_debug(trail, "nodes", "put");
253  return BDB_WRAP(fs, N_("storing node revision"),
254                  bfd->nodes->put(bfd->nodes, db_txn,
255                                  svn_fs_base__id_to_dbt(&key, id, pool),
256                                  svn_fs_base__skel_to_dbt(&value, skel,
257                                                           pool),
258                                  0));
259}
260