2 Unix SMB/CIFS implementation.
4 trivial database library - private includes
6 Copyright (C) Andrew Tridgell 2005
8 ** NOTE! The following LGPL license applies to the tdb
9 ** library. This does NOT imply that all of Samba is released
12 This library is free software; you can redistribute it and/or
13 modify it under the terms of the GNU Lesser General Public
14 License as published by the Free Software Foundation; either
15 version 3 of the License, or (at your option) any later version.
17 This library is distributed in the hope that it will be useful,
18 but WITHOUT ANY WARRANTY; without even the implied warranty of
19 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
20 Lesser General Public License for more details.
22 You should have received a copy of the GNU Lesser General Public
23 License along with this library; if not, see <http://www.gnu.org/licenses/>.
27 #include "system/filesys.h"
28 #include "system/time.h"
29 #include "system/shmem.h"
30 #include "system/select.h"
31 #include "system/wait.h"
34 /* #define TDB_TRACE 1 */
35 #ifndef HAVE_GETPAGESIZE
36 #define getpagesize() 0x2000
39 typedef uint32_t tdb_len_t;
40 typedef uint32_t tdb_off_t;
43 #define offsetof(t,f) ((unsigned int)&((t *)0)->f)
46 #define TDB_MAGIC_FOOD "TDB file\n"
47 #define TDB_VERSION (0x26011967 + 6)
48 #define TDB_MAGIC (0x26011999U)
49 #define TDB_FREE_MAGIC (~TDB_MAGIC)
50 #define TDB_DEAD_MAGIC (0xFEE1DEAD)
51 #define TDB_RECOVERY_MAGIC (0xf53bc0e7U)
52 #define TDB_RECOVERY_INVALID_MAGIC (0x0)
53 #define TDB_ALIGNMENT 4
54 #define DEFAULT_HASH_SIZE 131
55 #define FREELIST_TOP (sizeof(struct tdb_header))
56 #define TDB_ALIGN(x,a) (((x) + (a)-1) & ~((a)-1))
57 #define TDB_BYTEREV(x) (((((x)&0xff)<<24)|((x)&0xFF00)<<8)|(((x)>>8)&0xFF00)|((x)>>24))
58 #define TDB_DEAD(r) ((r)->magic == TDB_DEAD_MAGIC)
59 #define TDB_BAD_MAGIC(r) ((r)->magic != TDB_MAGIC && !TDB_DEAD(r))
60 #define TDB_HASH_TOP(hash) (FREELIST_TOP + (BUCKET(hash)+1)*sizeof(tdb_off_t))
61 #define TDB_HASHTABLE_SIZE(tdb) ((tdb->header.hash_size+1)*sizeof(tdb_off_t))
62 #define TDB_DATA_START(hash_size) (TDB_HASH_TOP(hash_size-1) + sizeof(tdb_off_t))
63 #define TDB_RECOVERY_HEAD offsetof(struct tdb_header, recovery_start)
64 #define TDB_SEQNUM_OFS offsetof(struct tdb_header, sequence_number)
65 #define TDB_PAD_BYTE 0x42
66 #define TDB_PAD_U32 0x42424242
68 /* NB assumes there is a local variable called "tdb" that is the
69 * current context, also takes doubly-parenthesized print-style
71 #define TDB_LOG(x) tdb->log.log_fn x
74 void tdb_trace(struct tdb_context *tdb, const char *op);
75 void tdb_trace_seqnum(struct tdb_context *tdb, uint32_t seqnum, const char *op);
76 void tdb_trace_open(struct tdb_context *tdb, const char *op,
77 unsigned hash_size, unsigned tdb_flags, unsigned open_flags);
78 void tdb_trace_ret(struct tdb_context *tdb, const char *op, int ret);
79 void tdb_trace_retrec(struct tdb_context *tdb, const char *op, TDB_DATA ret);
80 void tdb_trace_1rec(struct tdb_context *tdb, const char *op,
82 void tdb_trace_1rec_ret(struct tdb_context *tdb, const char *op,
83 TDB_DATA rec, int ret);
84 void tdb_trace_1rec_retrec(struct tdb_context *tdb, const char *op,
85 TDB_DATA rec, TDB_DATA ret);
86 void tdb_trace_2rec_flag_ret(struct tdb_context *tdb, const char *op,
87 TDB_DATA rec1, TDB_DATA rec2, unsigned flag,
89 void tdb_trace_2rec_retrec(struct tdb_context *tdb, const char *op,
90 TDB_DATA rec1, TDB_DATA rec2, TDB_DATA ret);
92 #define tdb_trace(tdb, op)
93 #define tdb_trace_seqnum(tdb, seqnum, op)
94 #define tdb_trace_open(tdb, op, hash_size, tdb_flags, open_flags)
95 #define tdb_trace_ret(tdb, op, ret)
96 #define tdb_trace_retrec(tdb, op, ret)
97 #define tdb_trace_1rec(tdb, op, rec)
98 #define tdb_trace_1rec_ret(tdb, op, rec, ret)
99 #define tdb_trace_1rec_retrec(tdb, op, rec, ret)
100 #define tdb_trace_2rec_flag_ret(tdb, op, rec1, rec2, flag, ret)
101 #define tdb_trace_2rec_retrec(tdb, op, rec1, rec2, ret)
102 #endif /* !TDB_TRACE */
106 #define ACTIVE_LOCK 4
107 #define TRANSACTION_LOCK 8
109 /* free memory if the pointer is valid and zero the pointer */
111 #define SAFE_FREE(x) do { if ((x) != NULL) {free(x); (x)=NULL;} } while(0)
114 #define BUCKET(hash) ((hash) % tdb->header.hash_size)
116 #define DOCONV() (tdb->flags & TDB_CONVERT)
117 #define CONVERT(x) (DOCONV() ? tdb_convert(&x, sizeof(x)) : &x)
120 /* the body of the database is made of one tdb_record for the free space
121 plus a separate data list for each hash value */
123 tdb_off_t next; /* offset of the next record in the list */
124 tdb_len_t rec_len; /* total byte length of record */
125 tdb_len_t key_len; /* byte length of key */
126 tdb_len_t data_len; /* byte length of data */
127 uint32_t full_hash; /* the full 32 bit hash of the key */
128 uint32_t magic; /* try to catch errors */
129 /* the following union is implied:
131 char record[rec_len];
136 uint32_t totalsize; (tailer)
142 /* this is stored at the front of every database */
144 char magic_food[32]; /* for /etc/magic */
145 uint32_t version; /* version of the code */
146 uint32_t hash_size; /* number of hash entries */
147 tdb_off_t rwlocks; /* obsolete - kept to detect old formats */
148 tdb_off_t recovery_start; /* offset of transaction recovery region */
149 tdb_off_t sequence_number; /* used when TDB_SEQNUM is set */
150 tdb_off_t reserved[29];
153 struct tdb_lock_type {
159 struct tdb_traverse_lock {
160 struct tdb_traverse_lock *next;
166 enum tdb_lock_flags {
167 /* WAIT == F_SETLKW, NOWAIT == F_SETLK */
170 /* If set, don't log an error on failure. */
172 /* If set, don't actually lock at all. */
173 TDB_LOCK_MARK_ONLY = 4,
177 int (*tdb_read)(struct tdb_context *, tdb_off_t , void *, tdb_len_t , int );
178 int (*tdb_write)(struct tdb_context *, tdb_off_t, const void *, tdb_len_t);
179 void (*next_hash_chain)(struct tdb_context *, uint32_t *);
180 int (*tdb_oob)(struct tdb_context *, tdb_off_t , int );
181 int (*tdb_expand_file)(struct tdb_context *, tdb_off_t , tdb_off_t );
182 int (*brlock)(struct tdb_context *, int, tdb_off_t, size_t, enum tdb_lock_flags);
183 int (*brunlock)(struct tdb_context *, int, tdb_off_t, size_t);
187 char *name; /* the name of the database */
188 void *map_ptr; /* where it is currently mapped */
189 int fd; /* open file descriptor for the database */
190 tdb_len_t map_size; /* how much space has been mapped */
191 int read_only; /* opened read-only */
192 int traverse_read; /* read-only traversal */
193 int traverse_write; /* read-write traversal */
194 struct tdb_lock_type allrecord_lock; /* .offset == upgradable */
196 struct tdb_lock_type *lockrecs; /* only real locks, all with count>0 */
197 enum TDB_ERROR ecode; /* error code for last tdb error */
198 struct tdb_header header; /* a cached copy of the header */
199 uint32_t flags; /* the flags passed to tdb_open */
200 struct tdb_traverse_lock travlocks; /* current traversal locks */
201 struct tdb_context *next; /* all tdbs to avoid multiple opens */
202 dev_t device; /* uniquely identifies this tdb */
203 ino_t inode; /* uniquely identifies this tdb */
204 struct tdb_logging_context log;
205 unsigned int (*hash_fn)(TDB_DATA *key);
206 int open_flags; /* flags used in the open - needed by reopen */
207 const struct tdb_methods *methods;
208 struct tdb_transaction *transaction;
210 int max_dead_records;
214 volatile sig_atomic_t *interrupt_sig_ptr;
221 int tdb_munmap(struct tdb_context *tdb);
222 void tdb_mmap(struct tdb_context *tdb);
223 int tdb_lock(struct tdb_context *tdb, int list, int ltype);
224 int tdb_lock_nonblock(struct tdb_context *tdb, int list, int ltype);
225 int tdb_nest_lock(struct tdb_context *tdb, uint32_t offset, int ltype,
226 enum tdb_lock_flags flags);
227 int tdb_nest_unlock(struct tdb_context *tdb, uint32_t offset, int ltype,
229 int tdb_unlock(struct tdb_context *tdb, int list, int ltype);
230 int tdb_brlock(struct tdb_context *tdb,
231 int rw_type, tdb_off_t offset, size_t len,
232 enum tdb_lock_flags flags);
233 int tdb_brunlock(struct tdb_context *tdb,
234 int rw_type, tdb_off_t offset, size_t len);
235 bool tdb_have_extra_locks(struct tdb_context *tdb);
236 void tdb_release_transaction_locks(struct tdb_context *tdb);
237 int tdb_transaction_lock(struct tdb_context *tdb, int ltype);
238 int tdb_transaction_unlock(struct tdb_context *tdb, int ltype);
239 int tdb_allrecord_lock(struct tdb_context *tdb, int ltype,
240 enum tdb_lock_flags flags, bool upgradable);
241 int tdb_allrecord_unlock(struct tdb_context *tdb, int ltype, bool mark_lock);
242 int tdb_allrecord_upgrade(struct tdb_context *tdb);
243 int tdb_write_lock_record(struct tdb_context *tdb, tdb_off_t off);
244 int tdb_write_unlock_record(struct tdb_context *tdb, tdb_off_t off);
245 int tdb_ofs_read(struct tdb_context *tdb, tdb_off_t offset, tdb_off_t *d);
246 int tdb_ofs_write(struct tdb_context *tdb, tdb_off_t offset, tdb_off_t *d);
247 void *tdb_convert(void *buf, uint32_t size);
248 int tdb_free(struct tdb_context *tdb, tdb_off_t offset, struct tdb_record *rec);
249 tdb_off_t tdb_allocate(struct tdb_context *tdb, tdb_len_t length, struct tdb_record *rec);
250 int tdb_ofs_read(struct tdb_context *tdb, tdb_off_t offset, tdb_off_t *d);
251 int tdb_ofs_write(struct tdb_context *tdb, tdb_off_t offset, tdb_off_t *d);
252 int tdb_lock_record(struct tdb_context *tdb, tdb_off_t off);
253 int tdb_unlock_record(struct tdb_context *tdb, tdb_off_t off);
254 int tdb_rec_read(struct tdb_context *tdb, tdb_off_t offset, struct tdb_record *rec);
255 int tdb_rec_write(struct tdb_context *tdb, tdb_off_t offset, struct tdb_record *rec);
256 int tdb_do_delete(struct tdb_context *tdb, tdb_off_t rec_ptr, struct tdb_record *rec);
257 unsigned char *tdb_alloc_read(struct tdb_context *tdb, tdb_off_t offset, tdb_len_t len);
258 int tdb_parse_data(struct tdb_context *tdb, TDB_DATA key,
259 tdb_off_t offset, tdb_len_t len,
260 int (*parser)(TDB_DATA key, TDB_DATA data,
263 tdb_off_t tdb_find_lock_hash(struct tdb_context *tdb, TDB_DATA key, uint32_t hash, int locktype,
264 struct tdb_record *rec);
265 void tdb_io_init(struct tdb_context *tdb);
266 int tdb_expand(struct tdb_context *tdb, tdb_off_t size);
267 int tdb_rec_free_read(struct tdb_context *tdb, tdb_off_t off,
268 struct tdb_record *rec);