vfs: update status of SMB_VFS_LISTXATTR
[samba.git] / lib / tdb / common / summary.c
1  /*
2    Trivial Database: human-readable summary code
3    Copyright (C) Rusty Russell 2010
4
5    This library is free software; you can redistribute it and/or
6    modify it under the terms of the GNU Lesser General Public
7    License as published by the Free Software Foundation; either
8    version 3 of the License, or (at your option) any later version.
9
10    This library is distributed in the hope that it will be useful,
11    but WITHOUT ANY WARRANTY; without even the implied warranty of
12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13    Lesser General Public License for more details.
14
15    You should have received a copy of the GNU Lesser General Public
16    License along with this library; if not, see <http://www.gnu.org/licenses/>.
17 */
18 #include "tdb_private.h"
19
20 #define SUMMARY_FORMAT \
21         "Size of file/data: %llu/%zu\n" \
22         "Header offset/logical size: %zu/%zu\n" \
23         "Number of records: %zu\n" \
24         "Incompatible hash: %s\n" \
25         "Active/supported feature flags: 0x%08x/0x%08x\n" \
26         "Robust mutexes locking: %s\n" \
27         "Smallest/average/largest keys: %zu/%zu/%zu\n" \
28         "Smallest/average/largest data: %zu/%zu/%zu\n" \
29         "Smallest/average/largest padding: %zu/%zu/%zu\n" \
30         "Number of dead records: %zu\n" \
31         "Smallest/average/largest dead records: %zu/%zu/%zu\n" \
32         "Number of free records: %zu\n" \
33         "Smallest/average/largest free records: %zu/%zu/%zu\n" \
34         "Number of hash chains: %zu\n" \
35         "Smallest/average/largest hash chains: %zu/%zu/%zu\n" \
36         "Number of uncoalesced records: %zu\n" \
37         "Smallest/average/largest uncoalesced runs: %zu/%zu/%zu\n" \
38         "Percentage keys/data/padding/free/dead/rechdrs&tailers/hashes: %.0f/%.0f/%.0f/%.0f/%.0f/%.0f/%.0f\n"
39
40 /* We don't use tally module, to keep upstream happy. */
41 struct tally {
42         size_t min, max, total;
43         size_t num;
44 };
45
46 static void tally_init(struct tally *tally)
47 {
48         tally->total = 0;
49         tally->num = 0;
50         tally->min = tally->max = 0;
51 }
52
53 static void tally_add(struct tally *tally, size_t len)
54 {
55         if (tally->num == 0)
56                 tally->max = tally->min = len;
57         else if (len > tally->max)
58                 tally->max = len;
59         else if (len < tally->min)
60                 tally->min = len;
61         tally->num++;
62         tally->total += len;
63 }
64
65 static size_t tally_mean(const struct tally *tally)
66 {
67         if (!tally->num)
68                 return 0;
69         return tally->total / tally->num;
70 }
71
72 static size_t get_hash_length(struct tdb_context *tdb, unsigned int i)
73 {
74         tdb_off_t rec_ptr;
75         struct tdb_chainwalk_ctx chainwalk;
76         size_t count = 0;
77
78         if (tdb_ofs_read(tdb, TDB_HASH_TOP(i), &rec_ptr) == -1)
79                 return 0;
80
81         tdb_chainwalk_init(&chainwalk, rec_ptr);
82
83         /* keep looking until we find the right record */
84         while (rec_ptr) {
85                 struct tdb_record r;
86                 bool ok;
87                 ++count;
88                 if (tdb_rec_read(tdb, rec_ptr, &r) == -1)
89                         return 0;
90                 rec_ptr = r.next;
91                 ok = tdb_chainwalk_check(tdb, &chainwalk, rec_ptr);
92                 if (!ok) {
93                         return SIZE_MAX;
94                 }
95         }
96         return count;
97 }
98
99 _PUBLIC_ char *tdb_summary(struct tdb_context *tdb)
100 {
101         off_t file_size;
102         tdb_off_t off, rec_off;
103         struct tally freet, keys, data, dead, extra, hashval, uncoal;
104         struct tdb_record rec;
105         char *ret = NULL;
106         bool locked;
107         size_t unc = 0;
108         int len;
109         struct tdb_record recovery;
110
111         /* Read-only databases use no locking at all: it's best-effort.
112          * We may have a write lock already, so skip that case too. */
113         if (tdb->read_only || tdb->allrecord_lock.count != 0) {
114                 locked = false;
115         } else {
116                 if (tdb_lockall_read(tdb) == -1)
117                         return NULL;
118                 locked = true;
119         }
120
121         if (tdb_recovery_area(tdb, tdb->methods, &rec_off, &recovery) != 0) {
122                 goto unlock;
123         }
124
125         tally_init(&freet);
126         tally_init(&keys);
127         tally_init(&data);
128         tally_init(&dead);
129         tally_init(&extra);
130         tally_init(&hashval);
131         tally_init(&uncoal);
132
133         for (off = TDB_DATA_START(tdb->hash_size);
134              off < tdb->map_size - 1;
135              off += sizeof(rec) + rec.rec_len) {
136                 if (tdb->methods->tdb_read(tdb, off, &rec, sizeof(rec),
137                                            DOCONV()) == -1)
138                         goto unlock;
139                 switch (rec.magic) {
140                 case TDB_MAGIC:
141                         tally_add(&keys, rec.key_len);
142                         tally_add(&data, rec.data_len);
143                         tally_add(&extra, rec.rec_len - (rec.key_len
144                                                          + rec.data_len));
145                         if (unc > 1)
146                                 tally_add(&uncoal, unc - 1);
147                         unc = 0;
148                         break;
149                 case TDB_FREE_MAGIC:
150                         tally_add(&freet, rec.rec_len);
151                         unc++;
152                         break;
153                 /* If we crash after ftruncate, we can get zeroes or fill. */
154                 case TDB_RECOVERY_INVALID_MAGIC:
155                 case 0x42424242:
156                         unc++;
157                         /* If it's a valid recovery, we can trust rec_len. */
158                         if (off != rec_off) {
159                                 rec.rec_len = tdb_dead_space(tdb, off)
160                                         - sizeof(rec);
161                         }
162
163                         FALL_THROUGH;
164                 case TDB_DEAD_MAGIC:
165                         tally_add(&dead, rec.rec_len);
166                         break;
167                 default:
168                         TDB_LOG((tdb, TDB_DEBUG_ERROR,
169                                  "Unexpected record magic 0x%x at offset %u\n",
170                                  rec.magic, off));
171                         goto unlock;
172                 }
173         }
174         if (unc > 1)
175                 tally_add(&uncoal, unc - 1);
176
177         for (off = 0; off < tdb->hash_size; off++)
178                 tally_add(&hashval, get_hash_length(tdb, off));
179
180         file_size = tdb->hdr_ofs + tdb->map_size;
181
182         len = asprintf(&ret, SUMMARY_FORMAT,
183                  (unsigned long long)file_size, keys.total+data.total,
184                  (size_t)tdb->hdr_ofs, (size_t)tdb->map_size,
185                  keys.num,
186                  (tdb->hash_fn == tdb_jenkins_hash)?"yes":"no",
187                  (unsigned)tdb->feature_flags, TDB_SUPPORTED_FEATURE_FLAGS,
188                  (tdb->feature_flags & TDB_FEATURE_FLAG_MUTEX)?"yes":"no",
189                  keys.min, tally_mean(&keys), keys.max,
190                  data.min, tally_mean(&data), data.max,
191                  extra.min, tally_mean(&extra), extra.max,
192                  dead.num,
193                  dead.min, tally_mean(&dead), dead.max,
194                  freet.num,
195                  freet.min, tally_mean(&freet), freet.max,
196                  hashval.num,
197                  hashval.min, tally_mean(&hashval), hashval.max,
198                  uncoal.total,
199                  uncoal.min, tally_mean(&uncoal), uncoal.max,
200                  keys.total * 100.0 / file_size,
201                  data.total * 100.0 / file_size,
202                  extra.total * 100.0 / file_size,
203                  freet.total * 100.0 / file_size,
204                  dead.total * 100.0 / file_size,
205                  (keys.num + freet.num + dead.num)
206                  * (sizeof(struct tdb_record) + sizeof(uint32_t))
207                  * 100.0 / file_size,
208                  tdb->hash_size * sizeof(tdb_off_t)
209                  * 100.0 / file_size);
210         if (len == -1) {
211                 goto unlock;
212         }
213
214 unlock:
215         if (locked) {
216                 tdb_unlockall_read(tdb);
217         }
218         return ret;
219 }