contrib/subversion/subversion/libsvn_fs_base/bdb/reps-table.c

   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 \f
  40 /*** Creating and opening the representations table. ***/
  41
  42 int
  43 svn_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 \f
  73 /*** Storing and retrieving reps.  ***/
  74
  75 svn_error_t *
  76 svn_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
 111 svn_error_t *
 112 svn_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
 137 svn_error_t *
 138 svn_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
 181 svn_error_t *
 182 svn_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 }