4 Trivial Database 2: private types and prototypes
5 Copyright (C) Rusty Russell 2010
7 This library is free software; you can redistribute it and/or
8 modify it under the terms of the GNU Lesser General Public
9 License as published by the Free Software Foundation; either
10 version 3 of the License, or (at your option) any later version.
12 This library is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 Lesser General Public License for more details.
17 You should have received a copy of the GNU Lesser General Public
18 License along with this library; if not, see <http://www.gnu.org/licenses/>.
21 #define _XOPEN_SOURCE 500
22 #define _FILE_OFFSET_BITS 64
37 #include <ccan/tdb2/tdb2.h>
38 #include <ccan/likely/likely.h>
39 #ifdef HAVE_BYTESWAP_H
47 /* #define TDB_TRACE 1 */
50 #define __STRING(x) #x
53 #ifndef __STRINGSTRING
54 #define __STRINGSTRING(x) __STRING(x)
58 #define __location__ __FILE__ ":" __STRINGSTRING(__LINE__)
61 typedef uint64_t tdb_len_t;
62 typedef uint64_t tdb_off_t;
64 #define TDB_MAGIC_FOOD "TDB file\n"
65 #define TDB_VERSION ((uint64_t)(0x26011967 + 7))
66 #define TDB_MAGIC ((uint64_t)0x1999)
67 #define TDB_FREE_MAGIC ((~(uint64_t)TDB_MAGIC) << 6)
68 #define TDB_COALESCING_MAGIC (0xBAD1DEA2FEEDULL << 6)
69 #define TDB_HASH_MAGIC (0xA1ABE11A01092008ULL)
70 #define TDB_RECOVERY_MAGIC (0xf53bc0e7U)
71 #define TDB_RECOVERY_INVALID_MAGIC (0x0)
73 #define TDB_OFF_ERR ((tdb_off_t)-1)
75 /* Prevent others from opening the file. */
76 #define TDB_OPEN_LOCK 0
77 /* Doing a transaction. */
78 #define TDB_TRANSACTION_LOCK 1
80 #define TDB_EXPANSION_LOCK 2
81 /* Hash chain locks. */
82 #define TDB_HASH_LOCK_START 3
84 /* Range for hash locks. */
85 #define TDB_HASH_LOCK_RANGE_BITS 30
86 #define TDB_HASH_LOCK_RANGE (1 << TDB_HASH_LOCK_RANGE_BITS)
88 /* We have 1024 entries in the top level. */
89 #define TDB_TOPLEVEL_HASH_BITS 10
90 /* And 64 entries in each sub-level: thus 64 bits exactly after 9 levels. */
91 #define TDB_SUBLEVEL_HASH_BITS 6
92 /* And 8 entries in each group, ie 8 groups per sublevel. */
93 #define TDB_HASH_GROUP_BITS 3
95 /* Extend file by least 32 times larger than needed. */
96 #define TDB_EXTENSION_FACTOR 32
98 /* We steal bits from the offsets to store hash info. */
99 #define TDB_OFF_HASH_GROUP_MASK ((1ULL << TDB_HASH_GROUP_BITS) - 1)
100 /* We steal this many upper bits, giving a maximum offset of 64 exabytes. */
101 #define TDB_OFF_UPPER_STEAL 8
102 #define TDB_OFF_UPPER_STEAL_EXTRA 7
103 #define TDB_OFF_UPPER_STEAL_TRUNCBIT 1
104 /* If this is set, hash is truncated (only 1 bit is valid). */
105 #define TDB_OFF_HASH_TRUNCATED_BIT 56
106 /* The bit number where we store next level of hash. */
107 #define TDB_OFF_HASH_EXTRA_BIT 57
108 /* Convenience mask to get actual offset. */
109 #define TDB_OFF_MASK \
110 (((1ULL << (64 - TDB_OFF_UPPER_STEAL)) - 1) - TDB_OFF_HASH_GROUP_MASK)
112 /* How many buckets in a free list: see size_to_bucket(). */
113 #define TDB_FREE_BUCKETS (64 - TDB_OFF_UPPER_STEAL)
115 /* We have to be able to fit a free record here. */
116 #define TDB_MIN_DATA_LEN \
117 (sizeof(struct tdb_free_record) - sizeof(struct tdb_used_record))
120 static inline uint64_t bswap_64(uint64_t x)
122 return (((x&0x000000FFULL)<<56)
123 | ((x&0x0000FF00ULL)<<48)
124 | ((x&0x00FF0000ULL)<<40)
125 | ((x&0xFF000000ULL)<<32)
126 | ((x>>8)&0xFF000000ULL)
127 | ((x>>16)&0x00FF0000ULL)
128 | ((x>>24)&0x0000FF00ULL)
129 | ((x>>32)&0x000000FFULL));
133 struct tdb_used_record {
134 /* For on-disk compatibility, we avoid bitfields:
140 uint64_t magic_and_meta;
141 /* The bottom key_len_bits*2 are key length, rest is data length. */
142 uint64_t key_and_data_len;
145 static inline unsigned rec_key_bits(const struct tdb_used_record *r)
147 return ((r->magic_and_meta >> 43) & ((1 << 5)-1)) * 2;
150 static inline uint64_t rec_key_length(const struct tdb_used_record *r)
152 return r->key_and_data_len & ((1ULL << rec_key_bits(r)) - 1);
155 static inline uint64_t rec_data_length(const struct tdb_used_record *r)
157 return r->key_and_data_len >> rec_key_bits(r);
160 static inline uint64_t rec_extra_padding(const struct tdb_used_record *r)
162 return (r->magic_and_meta >> 11) & 0xFFFFFFFF;
165 static inline uint32_t rec_hash(const struct tdb_used_record *r)
167 return r->magic_and_meta & ((1 << 11) - 1);
170 static inline uint16_t rec_magic(const struct tdb_used_record *r)
172 return (r->magic_and_meta >> 48);
175 struct tdb_free_record {
176 uint64_t magic_and_meta;
177 uint64_t data_len; /* Not counting these two fields. */
178 /* This is why the minimum record size is 16 bytes. */
182 static inline uint64_t frec_magic(const struct tdb_free_record *f)
184 return f->magic_and_meta;
187 /* this is stored at the front of every database */
189 char magic_food[64]; /* for /etc/magic */
190 /* FIXME: Make me 32 bit? */
191 uint64_t version; /* version of the code */
192 uint64_t hash_test; /* result of hashing HASH_MAGIC. */
193 uint64_t hash_seed; /* "random" seed written at creation time. */
194 tdb_off_t free_list; /* (First) free list. */
196 tdb_off_t reserved[27];
198 /* Top level hash table. */
199 tdb_off_t hashtable[1ULL << TDB_TOPLEVEL_HASH_BITS];
202 struct tdb_freelist {
203 struct tdb_used_record hdr;
204 tdb_off_t buckets[TDB_FREE_BUCKETS];
207 /* Information about a particular (locked) hash entry. */
209 /* Full hash value of entry. */
211 /* Start and length of lock acquired. */
212 tdb_off_t hlock_start;
213 tdb_len_t hlock_range;
214 /* Start of hash group. */
215 tdb_off_t group_start;
216 /* Bucket we belong in. */
217 unsigned int home_bucket;
218 /* Bucket we (or an empty space) were found in. */
219 unsigned int found_bucket;
220 /* How many bits of the hash are already used. */
221 unsigned int hash_used;
222 /* Current working group. */
223 tdb_off_t group[1 << TDB_HASH_GROUP_BITS];
226 struct traverse_info {
227 struct traverse_level {
229 /* We ignore groups here, and treat it as a big array. */
231 unsigned int total_buckets;
232 } levels[64 / TDB_SUBLEVEL_HASH_BITS];
233 unsigned int num_levels;
234 unsigned int toplevel_group;
235 /* This makes delete-everything-inside-traverse work as expected. */
239 enum tdb_lock_flags {
240 /* WAIT == F_SETLKW, NOWAIT == F_SETLK */
243 /* If set, don't log an error on failure. */
247 struct tdb_lock_type {
254 /* Filename of the database. */
257 /* Mmap (if any), or malloc (for TDB_INTERNAL). */
260 /* Are we accessing directly? (debugging check). */
263 /* Open file descriptor (undefined for TDB_INTERNAL). */
266 /* How much space has been mapped (<= current file size) */
269 /* Operating read-only? (Opened O_RDONLY, or in traverse_read) */
272 /* mmap read only? */
275 /* Error code for last tdb error. */
276 enum TDB_ERROR ecode;
278 /* the flags passed to tdb_open, for tdb_reopen. */
281 /* Logging function */
290 /* Set if we are in a transaction. */
291 struct tdb_transaction *transaction;
293 /* What freelist are we using? */
296 /* IO methods: changes for transactions. */
297 const struct tdb_methods *methods;
299 /* Lock information */
300 struct tdb_lock_type allrecord_lock;
301 uint64_t num_lockrecs;
302 struct tdb_lock_type *lockrecs;
304 /* Single list of all TDBs, to avoid multiple opens. */
305 struct tdb_context *next;
311 int (*read)(struct tdb_context *, tdb_off_t, void *, tdb_len_t);
312 int (*write)(struct tdb_context *, tdb_off_t, const void *, tdb_len_t);
313 int (*oob)(struct tdb_context *, tdb_off_t, bool);
314 int (*expand_file)(struct tdb_context *, tdb_len_t);
315 void *(*direct)(struct tdb_context *, tdb_off_t, size_t);
322 void tdb_hash_init(struct tdb_context *tdb);
324 /* Hash random memory. */
325 uint64_t tdb_hash(struct tdb_context *tdb, const void *ptr, size_t len);
328 uint64_t hash_record(struct tdb_context *tdb, tdb_off_t off);
330 /* Find and lock a hash entry (or where it would be). */
331 tdb_off_t find_and_lock(struct tdb_context *tdb,
335 struct tdb_used_record *rec,
336 struct traverse_info *tinfo);
338 int replace_in_hash(struct tdb_context *tdb,
342 int add_to_hash(struct tdb_context *tdb, struct hash_info *h,
345 int delete_from_hash(struct tdb_context *tdb, struct hash_info *h);
348 bool is_subhash(tdb_off_t val);
351 int tdb_flist_init(struct tdb_context *tdb);
353 /* If this fails, try tdb_expand. */
354 tdb_off_t alloc(struct tdb_context *tdb, size_t keylen, size_t datalen,
355 uint64_t hash, bool growing);
357 /* Put this record in a free list. */
358 int add_free_record(struct tdb_context *tdb,
359 tdb_off_t off, tdb_len_t len_with_header);
361 /* Set up header for a used record. */
362 int set_header(struct tdb_context *tdb,
363 struct tdb_used_record *rec,
364 uint64_t keylen, uint64_t datalen,
365 uint64_t actuallen, unsigned hashlow);
367 /* Used by tdb_check to verify. */
368 unsigned int size_to_bucket(tdb_len_t data_len);
369 tdb_off_t bucket_off(tdb_off_t flist_off, unsigned bucket);
372 /* Initialize tdb->methods. */
373 void tdb_io_init(struct tdb_context *tdb);
375 /* Convert endian of the buffer if required. */
376 void *tdb_convert(const struct tdb_context *tdb, void *buf, tdb_len_t size);
378 /* Unmap and try to map the tdb. */
379 void tdb_munmap(struct tdb_context *tdb);
380 void tdb_mmap(struct tdb_context *tdb);
382 /* Either make a copy into pad and return that, or return ptr into mmap.
383 * Converts endian (ie. will use pad in that case). */
384 void *tdb_get(struct tdb_context *tdb, tdb_off_t off, void *pad, size_t len);
386 /* Either alloc a copy, or give direct access. Release frees or noop. */
387 const void *tdb_access_read(struct tdb_context *tdb,
388 tdb_off_t off, tdb_len_t len, bool convert);
389 void *tdb_access_write(struct tdb_context *tdb,
390 tdb_off_t off, tdb_len_t len, bool convert);
392 /* Release result of tdb_access_read/write. */
393 void tdb_access_release(struct tdb_context *tdb, const void *p);
394 /* Commit result of tdb_acces_write. */
395 int tdb_access_commit(struct tdb_context *tdb, void *p);
397 /* Convenience routine to get an offset. */
398 tdb_off_t tdb_read_off(struct tdb_context *tdb, tdb_off_t off);
400 /* Write an offset at an offset. */
401 int tdb_write_off(struct tdb_context *tdb, tdb_off_t off, tdb_off_t val);
403 /* Clear an ondisk area. */
404 int zero_out(struct tdb_context *tdb, tdb_off_t off, tdb_len_t len);
406 /* Return a non-zero offset between >= start < end in this array (or end). */
407 tdb_off_t tdb_find_nonzero_off(struct tdb_context *tdb,
412 /* Return a zero offset in this array, or num. */
413 tdb_off_t tdb_find_zero_off(struct tdb_context *tdb, tdb_off_t off,
416 /* Even on files, we can get partial writes due to signals. */
417 bool tdb_pwrite_all(int fd, const void *buf, size_t len, tdb_off_t off);
418 bool tdb_pread_all(int fd, void *buf, size_t len, tdb_off_t off);
419 bool tdb_read_all(int fd, void *buf, size_t len);
421 /* Allocate and make a copy of some offset. */
422 void *tdb_alloc_read(struct tdb_context *tdb, tdb_off_t offset, tdb_len_t len);
424 /* Writes a converted copy of a record. */
425 int tdb_write_convert(struct tdb_context *tdb, tdb_off_t off,
426 const void *rec, size_t len);
428 /* Reads record and converts it */
429 int tdb_read_convert(struct tdb_context *tdb, tdb_off_t off,
430 void *rec, size_t len);
434 void tdb_lock_init(struct tdb_context *tdb);
436 /* Lock/unlock a range of hashes. */
437 int tdb_lock_hashes(struct tdb_context *tdb,
438 tdb_off_t hash_lock, tdb_len_t hash_range,
439 int ltype, enum tdb_lock_flags waitflag);
440 int tdb_unlock_hashes(struct tdb_context *tdb,
442 tdb_len_t hash_range, int ltype);
444 /* Lock/unlock a particular free bucket. */
445 int tdb_lock_free_bucket(struct tdb_context *tdb, tdb_off_t b_off,
446 enum tdb_lock_flags waitflag);
447 void tdb_unlock_free_bucket(struct tdb_context *tdb, tdb_off_t b_off);
449 /* Do we have any locks? */
450 bool tdb_has_locks(struct tdb_context *tdb);
452 /* Lock entire database. */
453 int tdb_allrecord_lock(struct tdb_context *tdb, int ltype,
454 enum tdb_lock_flags flags, bool upgradable);
455 int tdb_allrecord_unlock(struct tdb_context *tdb, int ltype);
457 /* Serialize db open. */
458 int tdb_lock_open(struct tdb_context *tdb);
459 void tdb_unlock_open(struct tdb_context *tdb);
461 /* Serialize db expand. */
462 int tdb_lock_expand(struct tdb_context *tdb, int ltype);
463 void tdb_unlock_expand(struct tdb_context *tdb, int ltype);
464 bool tdb_has_expansion_lock(struct tdb_context *tdb);
468 int first_in_hash(struct tdb_context *tdb, int ltype,
469 struct traverse_info *tinfo,
470 TDB_DATA *kbuf, size_t *dlen);
471 int next_in_hash(struct tdb_context *tdb, int ltype,
472 struct traverse_info *tinfo,
473 TDB_DATA *kbuf, size_t *dlen);
477 /* Low-level locking primitives. */
478 int tdb_nest_lock(struct tdb_context *tdb, tdb_off_t offset, int ltype,
479 enum tdb_lock_flags flags);
480 int tdb_nest_unlock(struct tdb_context *tdb, tdb_off_t offset, int ltype);
482 int tdb_munmap(struct tdb_context *tdb);
483 void tdb_mmap(struct tdb_context *tdb);
484 int tdb_lock(struct tdb_context *tdb, int list, int ltype);
485 int tdb_lock_nonblock(struct tdb_context *tdb, int list, int ltype);
486 bool tdb_have_locks(struct tdb_context *tdb);
487 int tdb_unlock(struct tdb_context *tdb, int list, int ltype);
488 int tdb_brlock(struct tdb_context *tdb,
489 int rw_type, tdb_off_t offset, size_t len,
490 enum tdb_lock_flags flags);
491 int tdb_brunlock(struct tdb_context *tdb,
492 int rw_type, tdb_off_t offset, size_t len);
493 bool tdb_have_extra_locks(struct tdb_context *tdb);
494 void tdb_release_extra_locks(struct tdb_context *tdb);
495 int tdb_transaction_lock(struct tdb_context *tdb, int ltype);
496 int tdb_transaction_unlock(struct tdb_context *tdb, int ltype);
497 int tdb_allrecord_lock(struct tdb_context *tdb, int ltype,
498 enum tdb_lock_flags flags, bool upgradable);
499 int tdb_allrecord_unlock(struct tdb_context *tdb, int ltype);
500 int tdb_allrecord_upgrade(struct tdb_context *tdb);
501 int tdb_write_lock_record(struct tdb_context *tdb, tdb_off_t off);
502 int tdb_write_unlock_record(struct tdb_context *tdb, tdb_off_t off);
503 int tdb_ofs_read(struct tdb_context *tdb, tdb_off_t offset, tdb_off_t *d);
504 int tdb_ofs_write(struct tdb_context *tdb, tdb_off_t offset, tdb_off_t *d);
505 int tdb_free(struct tdb_context *tdb, tdb_off_t offset, struct tdb_record *rec);
506 tdb_off_t tdb_allocate(struct tdb_context *tdb, tdb_len_t length, struct tdb_record *rec);
507 int tdb_ofs_read(struct tdb_context *tdb, tdb_off_t offset, tdb_off_t *d);
508 int tdb_ofs_write(struct tdb_context *tdb, tdb_off_t offset, tdb_off_t *d);
509 int tdb_lock_record(struct tdb_context *tdb, tdb_off_t off);
510 int tdb_unlock_record(struct tdb_context *tdb, tdb_off_t off);
511 bool tdb_needs_recovery(struct tdb_context *tdb);
512 int tdb_rec_read(struct tdb_context *tdb, tdb_off_t offset, struct tdb_record *rec);
513 int tdb_rec_write(struct tdb_context *tdb, tdb_off_t offset, struct tdb_record *rec);
514 int tdb_do_delete(struct tdb_context *tdb, tdb_off_t rec_ptr, struct tdb_record *rec);
515 unsigned char *tdb_alloc_read(struct tdb_context *tdb, tdb_off_t offset, tdb_len_t len);
516 int tdb_parse_data(struct tdb_context *tdb, TDB_DATA key,
517 tdb_off_t offset, tdb_len_t len,
518 int (*parser)(TDB_DATA key, TDB_DATA data,
521 tdb_off_t tdb_find_lock_hash(struct tdb_context *tdb, TDB_DATA key, uint32_t hash, int locktype,
522 struct tdb_record *rec);
523 void tdb_io_init(struct tdb_context *tdb);
524 int tdb_expand(struct tdb_context *tdb, tdb_off_t size);
525 int tdb_rec_free_read(struct tdb_context *tdb, tdb_off_t off,
526 struct tdb_record *rec);
530 void tdb_trace(struct tdb_context *tdb, const char *op);
531 void tdb_trace_seqnum(struct tdb_context *tdb, uint32_t seqnum, const char *op);
532 void tdb_trace_open(struct tdb_context *tdb, const char *op,
533 unsigned hash_size, unsigned tdb_flags, unsigned open_flags);
534 void tdb_trace_ret(struct tdb_context *tdb, const char *op, int ret);
535 void tdb_trace_retrec(struct tdb_context *tdb, const char *op, TDB_DATA ret);
536 void tdb_trace_1rec(struct tdb_context *tdb, const char *op,
538 void tdb_trace_1rec_ret(struct tdb_context *tdb, const char *op,
539 TDB_DATA rec, int ret);
540 void tdb_trace_1rec_retrec(struct tdb_context *tdb, const char *op,
541 TDB_DATA rec, TDB_DATA ret);
542 void tdb_trace_2rec_flag_ret(struct tdb_context *tdb, const char *op,
543 TDB_DATA rec1, TDB_DATA rec2, unsigned flag,
545 void tdb_trace_2rec_retrec(struct tdb_context *tdb, const char *op,
546 TDB_DATA rec1, TDB_DATA rec2, TDB_DATA ret);
548 #define tdb_trace(tdb, op)
549 #define tdb_trace_seqnum(tdb, seqnum, op)
550 #define tdb_trace_open(tdb, op, hash_size, tdb_flags, open_flags)
551 #define tdb_trace_ret(tdb, op, ret)
552 #define tdb_trace_retrec(tdb, op, ret)
553 #define tdb_trace_1rec(tdb, op, rec)
554 #define tdb_trace_1rec_ret(tdb, op, rec, ret)
555 #define tdb_trace_1rec_retrec(tdb, op, rec, ret)
556 #define tdb_trace_2rec_flag_ret(tdb, op, rec1, rec2, flag, ret)
557 #define tdb_trace_2rec_retrec(tdb, op, rec1, rec2, ret)
558 #endif /* !TDB_TRACE */