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lmdb.h
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1
165#ifndef _LMDB_H_
166#define _LMDB_H_
167
168#include <sys/types.h>
169
170#ifdef __cplusplus
171extern "C" {
172#endif
173
175#ifdef _MSC_VER
176typedef int mdb_mode_t;
177#else
178typedef mode_t mdb_mode_t;
179#endif
180
185#ifdef _WIN32
186typedef void *mdb_filehandle_t;
187#else
189#endif
190
199#define MDB_VERSION_MAJOR 0
201#define MDB_VERSION_MINOR 9
203#define MDB_VERSION_PATCH 32
204
206#define MDB_VERINT(a,b,c) (((a) << 24) | ((b) << 16) | (c))
207
209#define MDB_VERSION_FULL \
210 MDB_VERINT(MDB_VERSION_MAJOR,MDB_VERSION_MINOR,MDB_VERSION_PATCH)
211
213#define MDB_VERSION_DATE "January 29, 2024"
214
216#define MDB_VERSTR(a,b,c,d) "LMDB " #a "." #b "." #c ": (" d ")"
217
219#define MDB_VERFOO(a,b,c,d) MDB_VERSTR(a,b,c,d)
220
222#define MDB_VERSION_STRING \
223 MDB_VERFOO(MDB_VERSION_MAJOR,MDB_VERSION_MINOR,MDB_VERSION_PATCH,MDB_VERSION_DATE)
224
225
231typedef struct MDB_env MDB_env;
232
238typedef struct MDB_txn MDB_txn;
239
241typedef unsigned int MDB_dbi;
242
244typedef struct MDB_cursor MDB_cursor;
245
257typedef struct MDB_val {
258 size_t mv_size;
259 void *mv_data;
260} MDB_val;
261
263typedef int (MDB_cmp_func)(const MDB_val *a, const MDB_val *b);
264
279typedef void (MDB_rel_func)(MDB_val *item, void *oldptr, void *newptr, void *relctx);
280
285#define MDB_FIXEDMAP 0x01
287#define MDB_NOSUBDIR 0x4000
289#define MDB_NOSYNC 0x10000
291#define MDB_RDONLY 0x20000
293#define MDB_NOMETASYNC 0x40000
295#define MDB_WRITEMAP 0x80000
297#define MDB_MAPASYNC 0x100000
299#define MDB_NOTLS 0x200000
301#define MDB_NOLOCK 0x400000
303#define MDB_NORDAHEAD 0x800000
305#define MDB_NOMEMINIT 0x1000000
307
312#define MDB_REVERSEKEY 0x02
314#define MDB_DUPSORT 0x04
317#define MDB_INTEGERKEY 0x08
319#define MDB_DUPFIXED 0x10
321#define MDB_INTEGERDUP 0x20
323#define MDB_REVERSEDUP 0x40
325#define MDB_CREATE 0x40000
327
332#define MDB_NOOVERWRITE 0x10
337#define MDB_NODUPDATA 0x20
339#define MDB_CURRENT 0x40
343#define MDB_RESERVE 0x10000
345#define MDB_APPEND 0x20000
347#define MDB_APPENDDUP 0x40000
349#define MDB_MULTIPLE 0x80000
350/* @} */
351
358#define MDB_CP_COMPACT 0x01
359/* @} */
360
396
403#define MDB_SUCCESS 0
405#define MDB_KEYEXIST (-30799)
407#define MDB_NOTFOUND (-30798)
409#define MDB_PAGE_NOTFOUND (-30797)
411#define MDB_CORRUPTED (-30796)
413#define MDB_PANIC (-30795)
415#define MDB_VERSION_MISMATCH (-30794)
417#define MDB_INVALID (-30793)
419#define MDB_MAP_FULL (-30792)
421#define MDB_DBS_FULL (-30791)
423#define MDB_READERS_FULL (-30790)
425#define MDB_TLS_FULL (-30789)
427#define MDB_TXN_FULL (-30788)
429#define MDB_CURSOR_FULL (-30787)
431#define MDB_PAGE_FULL (-30786)
433#define MDB_MAP_RESIZED (-30785)
442#define MDB_INCOMPATIBLE (-30784)
444#define MDB_BAD_RSLOT (-30783)
446#define MDB_BAD_TXN (-30782)
448#define MDB_BAD_VALSIZE (-30781)
450#define MDB_BAD_DBI (-30780)
452#define MDB_LAST_ERRCODE MDB_BAD_DBI
454
456typedef struct MDB_stat {
457 unsigned int ms_psize;
459 unsigned int ms_depth;
463 size_t ms_entries;
464} MDB_stat;
465
467typedef struct MDB_envinfo {
469 size_t me_mapsize;
472 unsigned int me_maxreaders;
473 unsigned int me_numreaders;
475
483char *mdb_version(int *major, int *minor, int *patch);
484
495char *mdb_strerror(int err);
496
508int mdb_env_create(MDB_env **env);
509
631int mdb_env_open(MDB_env *env, const char *path, unsigned int flags, mdb_mode_t mode);
632
647int mdb_env_copy(MDB_env *env, const char *path);
648
663
687int mdb_env_copy2(MDB_env *env, const char *path, unsigned int flags);
688
706int mdb_env_copyfd2(MDB_env *env, mdb_filehandle_t fd, unsigned int flags);
707
714int mdb_env_stat(MDB_env *env, MDB_stat *stat);
715
722int mdb_env_info(MDB_env *env, MDB_envinfo *stat);
723
743int mdb_env_sync(MDB_env *env, int force);
744
753void mdb_env_close(MDB_env *env);
754
769int mdb_env_set_flags(MDB_env *env, unsigned int flags, int onoff);
770
781int mdb_env_get_flags(MDB_env *env, unsigned int *flags);
782
795int mdb_env_get_path(MDB_env *env, const char **path);
796
812
845int mdb_env_set_mapsize(MDB_env *env, size_t size);
846
864int mdb_env_set_maxreaders(MDB_env *env, unsigned int readers);
865
876int mdb_env_get_maxreaders(MDB_env *env, unsigned int *readers);
877
896int mdb_env_set_maxdbs(MDB_env *env, MDB_dbi dbs);
897
906
913int mdb_env_set_userctx(MDB_env *env, void *ctx);
914
920void *mdb_env_get_userctx(MDB_env *env);
921
928typedef void MDB_assert_func(MDB_env *env, const char *msg);
929
938
973int mdb_txn_begin(MDB_env *env, MDB_txn *parent, unsigned int flags, MDB_txn **txn);
974
980
990size_t mdb_txn_id(MDB_txn *txn);
991
1008int mdb_txn_commit(MDB_txn *txn);
1009
1018void mdb_txn_abort(MDB_txn *txn);
1019
1037void mdb_txn_reset(MDB_txn *txn);
1038
1053int mdb_txn_renew(MDB_txn *txn);
1054
1056#define mdb_open(txn,name,flags,dbi) mdb_dbi_open(txn,name,flags,dbi)
1058#define mdb_close(env,dbi) mdb_dbi_close(env,dbi)
1059
1128int mdb_dbi_open(MDB_txn *txn, const char *name, unsigned int flags, MDB_dbi *dbi);
1129
1142int mdb_stat(MDB_txn *txn, MDB_dbi dbi, MDB_stat *stat);
1143
1151int mdb_dbi_flags(MDB_txn *txn, MDB_dbi dbi, unsigned int *flags);
1152
1169void mdb_dbi_close(MDB_env *env, MDB_dbi dbi);
1170
1180int mdb_drop(MDB_txn *txn, MDB_dbi dbi, int del);
1181
1201int mdb_set_compare(MDB_txn *txn, MDB_dbi dbi, MDB_cmp_func *cmp);
1202
1224int mdb_set_dupsort(MDB_txn *txn, MDB_dbi dbi, MDB_cmp_func *cmp);
1225
1244int mdb_set_relfunc(MDB_txn *txn, MDB_dbi dbi, MDB_rel_func *rel);
1245
1260int mdb_set_relctx(MDB_txn *txn, MDB_dbi dbi, void *ctx);
1261
1288int mdb_get(MDB_txn *txn, MDB_dbi dbi, MDB_val *key, MDB_val *data);
1289
1337int mdb_put(MDB_txn *txn, MDB_dbi dbi, MDB_val *key, MDB_val *data,
1338 unsigned int flags);
1339
1362int mdb_del(MDB_txn *txn, MDB_dbi dbi, MDB_val *key, MDB_val *data);
1363
1386int mdb_cursor_open(MDB_txn *txn, MDB_dbi dbi, MDB_cursor **cursor);
1387
1394void mdb_cursor_close(MDB_cursor *cursor);
1395
1412int mdb_cursor_renew(MDB_txn *txn, MDB_cursor *cursor);
1413
1419
1425
1445int mdb_cursor_get(MDB_cursor *cursor, MDB_val *key, MDB_val *data,
1446 MDB_cursor_op op);
1447
1507int mdb_cursor_put(MDB_cursor *cursor, MDB_val *key, MDB_val *data,
1508 unsigned int flags);
1509
1531int mdb_cursor_del(MDB_cursor *cursor, unsigned int flags);
1532
1545int mdb_cursor_count(MDB_cursor *cursor, size_t *countp);
1546
1557int mdb_cmp(MDB_txn *txn, MDB_dbi dbi, const MDB_val *a, const MDB_val *b);
1558
1569int mdb_dcmp(MDB_txn *txn, MDB_dbi dbi, const MDB_val *a, const MDB_val *b);
1570
1577typedef int (MDB_msg_func)(const char *msg, void *ctx);
1578
1586int mdb_reader_list(MDB_env *env, MDB_msg_func *func, void *ctx);
1587
1594int mdb_reader_check(MDB_env *env, int *dead);
1596
1597#ifdef __cplusplus
1598}
1599#endif
1607
1608#endif /* _LMDB_H_ */
Opaque structure for navigating through a database.
Definition mdb.c:1219
Opaque structure for a database environment.
Definition mdb.c:1294
Opaque structure for a transaction handle.
Definition mdb.c:1119
void mdb_txn_reset(MDB_txn *txn)
Reset a read-only transaction.
Definition mdb.c:3101
MDB_cursor_op
Cursor Get operations.
Definition lmdb.h:366
int mdb_env_info(MDB_env *env, MDB_envinfo *stat)
Return information about the LMDB environment.
Definition mdb.c:9811
int MDB_msg_func(const char *msg, void *ctx)
A callback function used to print a message from the library.
Definition lmdb.h:1577
int mdb_cursor_put(MDB_cursor *cursor, MDB_val *key, MDB_val *data, unsigned int flags)
Store by cursor.
Definition mdb.c:7145
int mdb_cursor_del(MDB_cursor *cursor, unsigned int flags)
Delete current key/data pair.
Definition mdb.c:7261
int mdb_env_get_flags(MDB_env *env, unsigned int *flags)
Get environment flags.
Definition mdb.c:9723
MDB_dbi mdb_cursor_dbi(MDB_cursor *cursor)
Return the cursor's database handle.
Definition mdb.c:7846
int mdb_env_open(MDB_env *env, const char *path, unsigned int flags, mdb_mode_t mode)
Open an environment handle.
Definition mdb.c:5035
int mdb_reader_check(MDB_env *env, int *dead)
Check for stale entries in the reader lock table.
Definition mdb.c:10289
int mdb_env_copy2(MDB_env *env, const char *path, unsigned int flags)
Copy an LMDB environment to the specified path, with options.
Definition mdb.c:9685
int mdb_cursor_count(MDB_cursor *cursor, size_t *countp)
Return count of duplicates for current key.
Definition mdb.c:7785
void mdb_env_close(MDB_env *env)
Close the environment and release the memory map.
Definition mdb.c:5233
int mdb_env_copyfd(MDB_env *env, mdb_filehandle_t fd)
Copy an LMDB environment to the specified file descriptor.
int mdb_cursor_get(MDB_cursor *cursor, MDB_val *key, MDB_val *data, MDB_cursor_op op)
Retrieve by cursor.
Definition mdb.c:6391
int mdb_put(MDB_txn *txn, MDB_dbi dbi, MDB_val *key, MDB_val *data, unsigned int flags)
Store items into a database.
Definition mdb.c:9127
int mdb_env_copyfd2(MDB_env *env, mdb_filehandle_t fd, unsigned int flags)
Copy an LMDB environment to the specified file descriptor, with options.
void mdb_dbi_close(MDB_env *env, MDB_dbi dbi)
Close a database handle. Normally unnecessary. Use with care:
Definition mdb.c:9991
int mdb_env_copy(MDB_env *env, const char *path)
Copy an LMDB environment to the specified path.
Definition mdb.c:9705
int mdb_set_compare(MDB_txn *txn, MDB_dbi dbi, MDB_cmp_func *cmp)
Set a custom key comparison function for a database.
Definition mdb.c:10168
int mdb_set_relfunc(MDB_txn *txn, MDB_dbi dbi, MDB_rel_func *rel)
Set a relocation function for a MDB_FIXEDMAP database.
Definition mdb.c:10186
int mdb_txn_renew(MDB_txn *txn)
Renew a read-only transaction.
Definition mdb.c:2864
int mdb_env_set_assert(MDB_env *env, MDB_assert_func *func)
Definition mdb.c:9748
void * mdb_env_get_userctx(MDB_env *env)
Get the application information associated with the MDB_env.
Definition mdb.c:9742
int mdb_env_get_maxreaders(MDB_env *env, unsigned int *readers)
Get the maximum number of threads/reader slots for the environment.
Definition mdb.c:4188
void mdb_txn_abort(MDB_txn *txn)
Abandon all the operations of the transaction instead of saving them.
Definition mdb.c:3126
int mdb_set_relctx(MDB_txn *txn, MDB_dbi dbi, void *ctx)
Set a context pointer for a MDB_FIXEDMAP database's relocation function.
Definition mdb.c:10195
int mdb_env_set_flags(MDB_env *env, unsigned int flags, int onoff)
Set environment flags.
Definition mdb.c:9711
int mdb_txn_commit(MDB_txn *txn)
Commit all the operations of a transaction into the database.
Definition mdb.c:3737
int mdb_reader_list(MDB_env *env, MDB_msg_func *func, void *ctx)
Dump the entries in the reader lock table.
Definition mdb.c:10211
int mdb_env_sync(MDB_env *env, int force)
Flush the data buffers to disk.
Definition mdb.c:2565
int mdb_get(MDB_txn *txn, MDB_dbi dbi, MDB_val *key, MDB_val *data)
Get items from a database.
Definition mdb.c:5860
void MDB_assert_func(MDB_env *env, const char *msg)
A callback function for most LMDB assert() failures, called before printing the message and aborting.
Definition lmdb.h:928
int mdb_dbi_flags(MDB_txn *txn, MDB_dbi dbi, unsigned int *flags)
Retrieve the DB flags for a database handle.
Definition mdb.c:10008
char * mdb_strerror(int err)
Return a string describing a given error code.
Definition mdb.c:1517
int mdb_cursor_open(MDB_txn *txn, MDB_dbi dbi, MDB_cursor **cursor)
Create a cursor handle.
Definition mdb.c:7733
int mdb_env_set_mapsize(MDB_env *env, size_t size)
Set the size of the memory map to use for this environment.
Definition mdb.c:4133
int mdb_env_set_maxdbs(MDB_env *env, MDB_dbi dbs)
Set the maximum number of named databases for the environment.
Definition mdb.c:4168
int mdb_env_create(MDB_env **env)
Create an LMDB environment handle.
Definition mdb.c:4018
int mdb_env_get_maxkeysize(MDB_env *env)
Get the maximum size of keys and MDB_DUPSORT data we can write.
Definition mdb.c:10205
int mdb_del(MDB_txn *txn, MDB_dbi dbi, MDB_val *key, MDB_val *data)
Delete items from a database.
Definition mdb.c:8632
int mdb_drop(MDB_txn *txn, MDB_dbi dbi, int del)
Empty or delete+close a database.
Definition mdb.c:10116
int mdb_cmp(MDB_txn *txn, MDB_dbi dbi, const MDB_val *a, const MDB_val *b)
Compare two data items according to a particular database.
Definition mdb.c:1804
int mdb_dbi_open(MDB_txn *txn, const char *name, unsigned int flags, MDB_dbi *dbi)
Open a database in the environment.
Definition mdb.c:9852
int mdb_dcmp(MDB_txn *txn, MDB_dbi dbi, const MDB_val *a, const MDB_val *b)
Compare two data items according to a particular database.
Definition mdb.c:1810
int mdb_env_get_path(MDB_env *env, const char **path)
Return the path that was used in mdb_env_open().
Definition mdb.c:9759
int mdb_cursor_renew(MDB_txn *txn, MDB_cursor *cursor)
Renew a cursor handle.
Definition mdb.c:7768
int mdb_set_dupsort(MDB_txn *txn, MDB_dbi dbi, MDB_cmp_func *cmp)
Set a custom data comparison function for a MDB_DUPSORT database.
Definition mdb.c:10177
void mdb_cursor_close(MDB_cursor *cursor)
Close a cursor handle.
Definition mdb.c:7823
int mdb_txn_begin(MDB_env *env, MDB_txn *parent, unsigned int flags, MDB_txn **txn)
Create a transaction for use with the environment.
Definition mdb.c:2881
size_t mdb_txn_id(MDB_txn *txn)
Return the transaction's ID.
Definition mdb.c:2990
int mdb_env_set_maxreaders(MDB_env *env, unsigned int readers)
Set the maximum number of threads/reader slots for the environment.
Definition mdb.c:4178
int mdb_stat(MDB_txn *txn, MDB_dbi dbi, MDB_stat *stat)
Retrieve statistics for a database.
Definition mdb.c:9974
MDB_txn * mdb_cursor_txn(MDB_cursor *cursor)
Return the cursor's transaction handle.
Definition mdb.c:7839
int mdb_env_get_fd(MDB_env *env, mdb_filehandle_t *fd)
Return the filedescriptor for the given environment.
Definition mdb.c:9769
int mdb_env_set_userctx(MDB_env *env, void *ctx)
Set application information associated with the MDB_env.
Definition mdb.c:9733
int mdb_env_stat(MDB_env *env, MDB_stat *stat)
Return statistics about the LMDB environment.
Definition mdb.c:9798
char * mdb_version(int *major, int *minor, int *patch)
Return the LMDB library version information.
Definition mdb.c:1484
MDB_env * mdb_txn_env(MDB_txn *txn)
Returns the transaction's MDB_env.
Definition mdb.c:2983
@ MDB_PREV_MULTIPLE
Definition lmdb.h:393
@ MDB_SET
Definition lmdb.h:390
@ MDB_NEXT_DUP
Definition lmdb.h:380
@ MDB_GET_BOTH_RANGE
Definition lmdb.h:371
@ MDB_NEXT_MULTIPLE
Definition lmdb.h:382
@ MDB_GET_CURRENT
Definition lmdb.h:372
@ MDB_SET_KEY
Definition lmdb.h:391
@ MDB_FIRST_DUP
Definition lmdb.h:368
@ MDB_FIRST
Definition lmdb.h:367
@ MDB_LAST_DUP
Definition lmdb.h:377
@ MDB_GET_MULTIPLE
Definition lmdb.h:373
@ MDB_NEXT
Definition lmdb.h:379
@ MDB_PREV
Definition lmdb.h:386
@ MDB_PREV_DUP
Definition lmdb.h:387
@ MDB_NEXT_NODUP
Definition lmdb.h:385
@ MDB_PREV_NODUP
Definition lmdb.h:389
@ MDB_LAST
Definition lmdb.h:376
@ MDB_GET_BOTH
Definition lmdb.h:370
@ MDB_SET_RANGE
Definition lmdb.h:392
Information about the environment.
Definition lmdb.h:467
Statistics for a database in the environment.
Definition lmdb.h:456
unsigned int me_maxreaders
Definition lmdb.h:472
size_t ms_entries
Definition lmdb.h:463
size_t me_mapsize
Definition lmdb.h:469
size_t me_last_txnid
Definition lmdb.h:471
unsigned int ms_psize
Definition lmdb.h:457
void * mv_data
Definition lmdb.h:259
size_t mv_size
Definition lmdb.h:258
unsigned int ms_depth
Definition lmdb.h:459
size_t ms_overflow_pages
Definition lmdb.h:462
size_t ms_leaf_pages
Definition lmdb.h:461
size_t ms_branch_pages
Definition lmdb.h:460
void * me_mapaddr
Definition lmdb.h:468
unsigned int me_numreaders
Definition lmdb.h:473
size_t me_last_pgno
Definition lmdb.h:470
void MDB_rel_func(MDB_val *item, void *oldptr, void *newptr, void *relctx)
A callback function used to relocate a position-dependent data item in a fixed-address database.
Definition lmdb.h:279
unsigned int MDB_dbi
A handle for an individual database in the DB environment.
Definition lmdb.h:241
int MDB_cmp_func(const MDB_val *a, const MDB_val *b)
A callback function used to compare two keys in a database.
Definition lmdb.h:263
Generic structure used for passing keys and data in and out of the database.
Definition lmdb.h:257
int mdb_filehandle_t
Definition lmdb.h:188
mode_t mdb_mode_t
Definition lmdb.h:178