1/* load-index-cmd.c -- implements the dump-index sub-command.
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 "svn_pools.h"
24
25#include "private/svn_sorts_private.h"
26
27#include "fs_fs.h"
28#include "index.h"
29#include "util.h"
30#include "transaction.h"
31
32/* From the ENTRIES array of svn_fs_fs__p2l_entry_t*, sorted by offset,
33 * return the first offset behind the last item. */
34static apr_off_t
35get_max_covered(apr_array_header_t *entries)
36{
37  const svn_fs_fs__p2l_entry_t *entry;
38  if (entries->nelts == 0)
39    return -1;
40
41  entry = APR_ARRAY_IDX(entries, entries->nelts - 1,
42                        const svn_fs_fs__p2l_entry_t *);
43  return entry->offset + entry->size;
44}
45
46/* Make sure that the svn_fs_fs__p2l_entry_t* in ENTRIES are consecutive
47 * and non-overlapping.  Use SCRATCH_POOL for temporaries. */
48static svn_error_t *
49check_all_covered(apr_array_header_t *entries,
50                  apr_pool_t *scratch_pool)
51{
52  int i;
53  apr_off_t expected = 0;
54  for (i = 0; i < entries->nelts; ++i)
55    {
56      const svn_fs_fs__p2l_entry_t *entry
57        = APR_ARRAY_IDX(entries, i, const svn_fs_fs__p2l_entry_t *);
58
59      if (entry->offset < expected)
60        return svn_error_createf(SVN_ERR_INVALID_INPUT, NULL,
61                                 "Overlapping index data for offset %s",
62                                 apr_psprintf(scratch_pool,
63                                              "%" APR_UINT64_T_HEX_FMT,
64                                              (apr_uint64_t)expected));
65
66      if (entry->offset > expected)
67        return svn_error_createf(SVN_ERR_INVALID_INPUT, NULL,
68                                 "Missing index data for offset %s",
69                                 apr_psprintf(scratch_pool,
70                                              "%" APR_UINT64_T_HEX_FMT,
71                                              (apr_uint64_t)expected));
72
73      expected = entry->offset + entry->size;
74    }
75
76  return SVN_NO_ERROR;
77}
78
79/* A svn_sort__array compatible comparator function, sorting the
80 * svn_fs_fs__p2l_entry_t** given in LHS, RHS by offset. */
81static int
82compare_p2l_entry_revision(const void *lhs,
83                           const void *rhs)
84{
85  const svn_fs_fs__p2l_entry_t *lhs_entry
86    =*(const svn_fs_fs__p2l_entry_t *const *)lhs;
87  const svn_fs_fs__p2l_entry_t *rhs_entry
88    =*(const svn_fs_fs__p2l_entry_t *const *)rhs;
89
90  if (lhs_entry->offset < rhs_entry->offset)
91    return -1;
92
93  return lhs_entry->offset == rhs_entry->offset ? 0 : 1;
94}
95
96svn_error_t *
97svn_fs_fs__load_index(svn_fs_t *fs,
98                      svn_revnum_t revision,
99                      apr_array_header_t *entries,
100                      apr_pool_t *scratch_pool)
101{
102  apr_pool_t *subpool = svn_pool_create(scratch_pool);
103
104  /* Check the FS format number. */
105  if (! svn_fs_fs__use_log_addressing(fs))
106    return svn_error_create(SVN_ERR_FS_UNSUPPORTED_FORMAT, NULL, NULL);
107
108  /* P2L index must be written in offset order.
109   * Sort ENTRIES accordingly. */
110  svn_sort__array(entries, compare_p2l_entry_revision);
111
112  /* Treat an empty array as a no-op instead error. */
113  if (entries->nelts != 0)
114    {
115      const char *l2p_proto_index;
116      const char *p2l_proto_index;
117      svn_fs_fs__revision_file_t *rev_file;
118      svn_error_t *err;
119      apr_off_t max_covered = get_max_covered(entries);
120
121      /* Ensure that the index data is complete. */
122      SVN_ERR(check_all_covered(entries, scratch_pool));
123
124      /* Open rev / pack file & trim indexes + footer off it. */
125      SVN_ERR(svn_fs_fs__open_pack_or_rev_file_writable(&rev_file, fs,
126                                                        revision, subpool,
127                                                        subpool));
128
129      /* Remove the existing index info. */
130      err = svn_fs_fs__auto_read_footer(rev_file);
131      if (err)
132        {
133          /* Even the index footer cannot be read, even less be trusted.
134           * Take the range of valid data from the new index data. */
135          svn_error_clear(err);
136          SVN_ERR(svn_io_file_trunc(rev_file->file, max_covered,
137                                    subpool));
138        }
139      else
140        {
141          /* We assume that the new index data covers all contents.
142           * Error out if it doesn't.  The user can always truncate
143           * the file themselves. */
144          if (max_covered != rev_file->l2p_offset)
145            return svn_error_createf(SVN_ERR_INVALID_INPUT, NULL,
146                       "New index data ends at %s, old index ended at %s",
147                       apr_psprintf(scratch_pool, "%" APR_UINT64_T_HEX_FMT,
148                                    (apr_uint64_t)max_covered),
149                       apr_psprintf(scratch_pool, "%" APR_UINT64_T_HEX_FMT,
150                                    (apr_uint64_t) rev_file->l2p_offset));
151
152          SVN_ERR(svn_io_file_trunc(rev_file->file, rev_file->l2p_offset,
153                                    subpool));
154        }
155
156      /* Create proto index files for the new index data
157       * (will be cleaned up automatically with iterpool). */
158      SVN_ERR(svn_fs_fs__p2l_index_from_p2l_entries(&p2l_proto_index, fs,
159                                                    rev_file, entries,
160                                                    subpool, subpool));
161      SVN_ERR(svn_fs_fs__l2p_index_from_p2l_entries(&l2p_proto_index, fs,
162                                                    entries, subpool,
163                                                    subpool));
164
165      /* Combine rev data with new index data. */
166      SVN_ERR(svn_fs_fs__add_index_data(fs, rev_file->file, l2p_proto_index,
167                                        p2l_proto_index,
168                                        rev_file->start_revision, subpool));
169    }
170
171  svn_pool_destroy(subpool);
172
173  return SVN_NO_ERROR;
174}
175