2 * @brief memory-mapped database library
4 * A Btree-based database management library modeled loosely on the
5 * BerkeleyDB API, but much simplified.
8 * Copyright 2011 Howard Chu, Symas Corp.
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted only as authorized by the OpenLDAP
15 * A copy of this license is available in the file LICENSE in the
16 * top-level directory of the distribution or, alternatively, at
17 * <http://www.OpenLDAP.org/license.html>.
19 * This code is derived from btree.c written by Martin Hedenfalk.
21 * Copyright (c) 2009, 2010 Martin Hedenfalk <martin@bzero.se>
23 * Permission to use, copy, modify, and distribute this software for any
24 * purpose with or without fee is hereby granted, provided that the above
25 * copyright notice and this permission notice appear in all copies.
27 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
28 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
29 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
30 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
31 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
32 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
33 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
35 #include <sys/types.h>
37 #include <sys/param.h>
43 #ifdef HAVE_SYS_FILE_H
66 /** @defgroup internal MDB Internals
69 /** @defgroup compat Windows Compatibility Macros
73 #define pthread_t DWORD
74 #define pthread_mutex_t HANDLE
75 #define pthread_key_t DWORD
76 #define pthread_self() GetCurrentThreadId()
77 #define pthread_key_create(x,y) *(x) = TlsAlloc()
78 #define pthread_key_delete(x) TlsFree(x)
79 #define pthread_getspecific(x) TlsGetValue(x)
80 #define pthread_setspecific(x,y) TlsSetValue(x,y)
81 #define pthread_mutex_unlock(x) ReleaseMutex(x)
82 #define pthread_mutex_lock(x) WaitForSingleObject(x, INFINITE)
83 #define LOCK_MUTEX_R(env) pthread_mutex_lock(env->me_rmutex)
84 #define UNLOCK_MUTEX_R(env) pthread_mutex_unlock(env->me_rmutex)
85 #define LOCK_MUTEX_W(env) pthread_mutex_lock(env->me_wmutex)
86 #define UNLOCK_MUTEX_W(env) pthread_mutex_unlock(env->me_wmutex)
87 #define getpid() GetCurrentProcessId()
88 #define fdatasync(fd) !FlushFileBuffers(fd)
89 #define ErrCode() GetLastError()
90 #define GetPageSize(x) {SYSTEM_INFO si; GetSystemInfo(&si); (x) = si.dwPageSize;}
91 #define close(fd) CloseHandle(fd)
92 #define munmap(ptr,len) UnmapViewOfFile(ptr)
94 #define LOCK_MUTEX_R(env) pthread_mutex_lock(&env->me_txns->mti_mutex)
95 #define UNLOCK_MUTEX_R(env) pthread_mutex_unlock(&env->me_txns->mti_mutex)
96 #define LOCK_MUTEX_W(env) pthread_mutex_lock(&env->me_txns->mti_wmutex)
97 #define UNLOCK_MUTEX_W(env) pthread_mutex_unlock(&env->me_txns->mti_wmutex)
98 #define ErrCode() errno
100 #define INVALID_HANDLE_VALUE -1
101 #define GetPageSize(x) (x) = sysconf(_SC_PAGE_SIZE)
107 /* Note: If O_DSYNC is undefined but exists in /usr/include,
108 * preferably set some compiler flag to get the definition.
109 * Otherwise compile with the less efficient -DMDB_DSYNC=O_SYNC.
112 # define MDB_DSYNC O_DSYNC
116 typedef ULONG pgno_t;
122 #if !(__STDC_VERSION__ >= 199901L || defined(__GNUC__))
123 # define DPRINTF (void) /* Vararg macros may be unsupported */
125 # define DPRINTF(fmt, ...) /* Requires 2 or more args */ \
126 fprintf(stderr, "%s:%d:(%p) " fmt "\n", __func__, __LINE__, pthread_self(), __VA_ARGS__)
128 # define DPRINTF(fmt, ...) ((void) 0)
130 #define DPUTS(arg) DPRINTF("%s", arg)
132 #define PAGESIZE 4096
133 #define MDB_MINKEYS 2
134 #define MDB_MAGIC 0xBEEFC0DE
135 #define MDB_VERSION 1
136 #define MAXKEYSIZE 511
138 #define KBUF (MAXKEYSIZE*2+1)
139 #define DKBUF char kbuf[KBUF]
140 #define DKEY(x) mdb_dkey(x, kbuf)
146 /* The DB view is always consistent because all writes are wrapped in
147 * the wmutex. Finer-grained locks aren't necessary.
153 #define LAZY_MUTEX_LOCK(x)
154 #define LAZY_MUTEX_UNLOCK(x)
155 #define LAZY_RWLOCK_UNLOCK(x)
156 #define LAZY_RWLOCK_WRLOCK(x)
157 #define LAZY_RWLOCK_RDLOCK(x)
158 #define LAZY_RWLOCK_DEF(x)
159 #define LAZY_RWLOCK_INIT(x,y)
160 #define LAZY_RWLOCK_DESTROY(x)
162 #define LAZY_MUTEX_LOCK(x) pthread_mutex_lock(x)
163 #define LAZY_MUTEX_UNLOCK(x) pthread_mutex_unlock(x)
164 #define LAZY_RWLOCK_UNLOCK(x) pthread_rwlock_unlock(x)
165 #define LAZY_RWLOCK_WRLOCK(x) pthread_rwlock_wrlock(x)
166 #define LAZY_RWLOCK_RDLOCK(x) pthread_rwlock_rdlock(x)
167 #define LAZY_RWLOCK_DEF(x) pthread_rwlock_t x
168 #define LAZY_RWLOCK_INIT(x,y) pthread_rwlock_init(x,y)
169 #define LAZY_RWLOCK_DESTROY(x) pthread_rwlock_destroy(x)
172 #define P_INVALID (~0UL)
174 #define F_ISSET(w, f) (((w) & (f)) == (f))
176 typedef uint16_t indx_t;
178 #define DEFAULT_READERS 126
179 #define DEFAULT_MAPSIZE 1048576
181 /* Lock descriptor stuff */
183 #define CACHELINE 64 /* most CPUs. Itanium uses 128 */
186 typedef struct MDB_rxbody {
192 typedef struct MDB_reader {
195 #define mr_txnid mru.mrx.mrb_txnid
196 #define mr_pid mru.mrx.mrb_pid
197 #define mr_tid mru.mrx.mrb_tid
198 /* cache line alignment */
199 char pad[(sizeof(MDB_rxbody)+CACHELINE-1) & ~(CACHELINE-1)];
203 typedef struct MDB_txbody {
205 uint32_t mtb_version;
206 /* For POSIX the actual mutexes reside in shared memory.
207 * On Windows, mutexes are allocated by the kernel; we store
208 * the name in shared memory so that other processes can
214 pthread_mutex_t mtb_mutex;
217 uint32_t mtb_numreaders;
218 uint32_t mtb_me_toggle;
221 typedef struct MDB_txninfo {
224 #define mti_magic mt1.mtb.mtb_magic
225 #define mti_version mt1.mtb.mtb_version
226 #define mti_mutex mt1.mtb.mtb_mutex
227 #define mti_rmname mt1.mtb.mtb_rmname
228 #define mti_txnid mt1.mtb.mtb_txnid
229 #define mti_numreaders mt1.mtb.mtb_numreaders
230 #define mti_me_toggle mt1.mtb.mtb_me_toggle
231 char pad[(sizeof(MDB_txbody)+CACHELINE-1) & ~(CACHELINE-1)];
236 #define mti_wmname mt2.mt2_wmname
238 pthread_mutex_t mt2_wmutex;
239 #define mti_wmutex mt2.mt2_wmutex
241 char pad[(sizeof(pthread_mutex_t)+CACHELINE-1) & ~(CACHELINE-1)];
243 MDB_reader mti_readers[1];
246 /* Common header for all page types. Overflow pages
247 * occupy a number of contiguous pages with no
248 * headers on any page after the first.
250 typedef struct MDB_page { /* represents a page of storage */
251 #define mp_pgno mp_p.p_pgno
253 pgno_t p_pgno; /* page number */
254 void * p_align; /* for IL32P64 */
256 #define P_BRANCH 0x01 /* branch page */
257 #define P_LEAF 0x02 /* leaf page */
258 #define P_OVERFLOW 0x04 /* overflow page */
259 #define P_META 0x08 /* meta page */
260 #define P_DIRTY 0x10 /* dirty page */
261 #define P_LEAF2 0x20 /* DB with small, fixed size keys and no data */
263 #define mp_lower mp_pb.pb.pb_lower
264 #define mp_upper mp_pb.pb.pb_upper
265 #define mp_pages mp_pb.pb_pages
268 indx_t pb_lower; /* lower bound of free space */
269 indx_t pb_upper; /* upper bound of free space */
271 uint32_t pb_pages; /* number of overflow pages */
273 indx_t mp_ptrs[1]; /* dynamic size */
276 #define PAGEHDRSZ ((unsigned) offsetof(MDB_page, mp_ptrs))
278 #define NUMKEYS(p) (((p)->mp_lower - PAGEHDRSZ) >> 1)
279 #define SIZELEFT(p) (indx_t)((p)->mp_upper - (p)->mp_lower)
280 #define PAGEFILL(env, p) (1000L * ((env)->me_psize - PAGEHDRSZ - SIZELEFT(p)) / \
281 ((env)->me_psize - PAGEHDRSZ))
282 #define IS_LEAF(p) F_ISSET((p)->mp_flags, P_LEAF)
283 #define IS_LEAF2(p) F_ISSET((p)->mp_flags, P_LEAF2)
284 #define IS_BRANCH(p) F_ISSET((p)->mp_flags, P_BRANCH)
285 #define IS_OVERFLOW(p) F_ISSET((p)->mp_flags, P_OVERFLOW)
287 #define OVPAGES(size, psize) ((PAGEHDRSZ-1 + (size)) / (psize) + 1)
289 typedef struct MDB_db {
290 uint32_t md_pad; /* also ksize for LEAF2 pages */
293 ULONG md_branch_pages;
295 ULONG md_overflow_pages;
303 typedef struct MDB_meta { /* meta (footer) page content */
306 void *mm_address; /* address for fixed mapping */
307 size_t mm_mapsize; /* size of mmap region */
308 MDB_db mm_dbs[2]; /* first is free space, 2nd is main db */
309 #define mm_psize mm_dbs[0].md_pad
310 #define mm_flags mm_dbs[0].md_flags
311 pgno_t mm_last_pg; /* last used page in file */
312 ULONG mm_txnid; /* txnid that committed this page */
315 typedef struct MDB_dhead { /* a dirty page */
317 unsigned md_pi; /* parent index */
321 typedef struct MDB_dpage {
326 typedef struct MDB_oldpages {
327 struct MDB_oldpages *mo_next;
329 pgno_t mo_pages[1]; /* dynamic */
332 typedef struct MDB_pageparent {
338 static MDB_dpage *mdb_alloc_page(MDB_txn *txn, MDB_dbi dbi, MDB_page *parent, unsigned int parent_idx, int num);
339 static int mdb_touch(MDB_txn *txn, MDB_dbi dbi, MDB_pageparent *mp);
341 typedef struct MDB_ppage { /* ordered list of pages */
343 unsigned int mp_ki; /* cursor index on page */
346 #define CURSOR_TOP(c) (&(c)->mc_stack[(c)->mc_snum-1])
347 #define CURSOR_PARENT(c) (&(c)->mc_stack[(c)->mc_snum-2])
348 #define CURSOR_STACK 32
353 struct MDB_xcursor *mc_xcursor;
356 unsigned int mc_snum; /* number of pushed pages */
357 unsigned int mc_flags;
358 #define C_INITIALIZED 0x01
360 #define C_XDIRTY 0x04
361 MDB_ppage mc_stack[CURSOR_STACK]; /* stack of parent pages */
364 #define METADATA(p) ((void *)((char *)(p) + PAGEHDRSZ))
366 /* We guarantee 2-byte alignment for nodes */
367 typedef struct MDB_node {
368 /* lo and hi are used for data size on leaf nodes and for
369 * child pgno on branch nodes. On 64 bit platforms, flags
370 * is also used for pgno. (branch nodes ignore flags)
372 unsigned short mn_lo;
373 unsigned short mn_hi;
374 unsigned short mn_flags;
375 #define F_BIGDATA 0x01 /* data put on overflow page */
376 #define F_SUBDATA 0x02 /* data is a sub-database */
377 #define F_DUPDATA 0x04 /* data has duplicates */
378 unsigned short mn_ksize; /* key size */
382 typedef struct MDB_dbx {
384 MDB_cmp_func *md_cmp; /* user compare function */
385 MDB_cmp_func *md_dcmp; /* user dupsort function */
386 MDB_rel_func *md_rel; /* user relocate function */
388 unsigned int md_dirty;
392 pgno_t mt_next_pgno; /* next unallocated page */
395 pgno_t *mt_free_pgs; /* this is an IDL */
397 ID2L dirty_list; /* modified pages */
400 MDB_dbx *mt_dbxs; /* array */
402 unsigned int mt_numdbs;
404 #define MDB_TXN_RDONLY 0x01 /* read-only transaction */
405 #define MDB_TXN_ERROR 0x02 /* an error has occurred */
406 unsigned int mt_flags;
407 unsigned int mt_toggle;
410 /* Context for sorted-dup records */
411 typedef struct MDB_xcursor {
412 MDB_cursor mx_cursor;
421 HANDLE me_mfd; /* just for writing the meta pages */
422 #define MDB_FATAL_ERROR 0x80000000U
424 uint32_t me_extrapad; /* unused for now */
425 unsigned int me_maxreaders;
426 unsigned int me_numdbs;
427 unsigned int me_maxdbs;
430 MDB_txninfo *me_txns;
431 MDB_meta *me_metas[2];
432 MDB_txn *me_txn; /* current write transaction */
434 off_t me_size; /* current file size */
435 pgno_t me_maxpg; /* me_mapsize / me_psize */
436 unsigned int me_psize;
437 unsigned int me_db_toggle;
438 MDB_dbx *me_dbxs; /* array */
440 MDB_oldpages *me_pghead;
441 pthread_key_t me_txkey; /* thread-key for readers */
442 MDB_dpage *me_dpages;
443 pgno_t me_free_pgs[MDB_IDL_UM_SIZE];
444 ID2 me_dirty_list[MDB_IDL_UM_SIZE];
445 LAZY_RWLOCK_DEF(me_dblock);
447 HANDLE me_rmutex; /* Windows mutexes don't reside in shared mem */
452 #define NODESIZE offsetof(MDB_node, mn_data)
454 #define INDXSIZE(k) (NODESIZE + ((k) == NULL ? 0 : (k)->mv_size))
455 #define LEAFSIZE(k, d) (NODESIZE + (k)->mv_size + (d)->mv_size)
456 #define NODEPTR(p, i) ((MDB_node *)((char *)(p) + (p)->mp_ptrs[i]))
457 #define NODEKEY(node) (void *)((node)->mn_data)
458 #define NODEDATA(node) (void *)((char *)(node)->mn_data + (node)->mn_ksize)
459 #if LONG_MAX == 0x7fffffff
460 #define NODEPGNO(node) ((node)->mn_lo | ((node)->mn_hi << 16))
461 #define SETPGNO(node,pgno) do { \
462 (node)->mn_lo = (pgno) & 0xffff; (node)->mn_hi = (pgno) >> 16;} while(0)
464 #define NODEPGNO(node) ((node)->mn_lo | ((node)->mn_hi << 16) | ((unsigned long)(node)->mn_flags << 32))
465 #define SETPGNO(node,pgno) do { \
466 (node)->mn_lo = (pgno) & 0xffff; (node)->mn_hi = (pgno) >> 16; \
467 (node)->mn_flags = (pgno) >> 32; } while(0)
469 #define NODEDSZ(node) ((node)->mn_lo | ((unsigned)(node)->mn_hi << 16))
470 #define SETDSZ(node,size) do { \
471 (node)->mn_lo = (size) & 0xffff; (node)->mn_hi = (size) >> 16;} while(0)
472 #define NODEKSZ(node) ((node)->mn_ksize)
473 #define LEAF2KEY(p, i, ks) ((char *)(p) + PAGEHDRSZ + ((i)*(ks)))
475 #define MDB_SET_KEY(node, key) if (key!=NULL) {(key)->mv_size = NODEKSZ(node); (key)->mv_data = NODEKEY(node);}
477 #define MDB_COMMIT_PAGES 64 /* max number of pages to write in one commit */
479 static int mdb_search_page_root(MDB_txn *txn,
480 MDB_dbi dbi, MDB_val *key,
481 MDB_cursor *cursor, int modify,
482 MDB_pageparent *mpp);
483 static int mdb_search_page(MDB_txn *txn,
484 MDB_dbi dbi, MDB_val *key,
485 MDB_cursor *cursor, int modify,
486 MDB_pageparent *mpp);
488 static int mdb_env_read_header(MDB_env *env, MDB_meta *meta);
489 static int mdb_env_read_meta(MDB_env *env, int *which);
490 static int mdb_env_write_meta(MDB_txn *txn);
491 static int mdb_get_page(MDB_txn *txn, pgno_t pgno, MDB_page **mp);
493 static MDB_node *mdb_search_node(MDB_txn *txn, MDB_dbi dbi, MDB_page *mp,
494 MDB_val *key, int *exactp, unsigned int *kip);
495 static int mdb_add_node(MDB_txn *txn, MDB_dbi dbi, MDB_page *mp,
496 indx_t indx, MDB_val *key, MDB_val *data,
497 pgno_t pgno, uint8_t flags);
498 static void mdb_del_node(MDB_page *mp, indx_t indx, int ksize);
499 static int mdb_del0(MDB_cursor *mc, unsigned int ki,
500 MDB_pageparent *mpp, MDB_node *leaf);
501 static int mdb_read_data(MDB_txn *txn, MDB_node *leaf, MDB_val *data);
503 static int mdb_rebalance(MDB_txn *txn, MDB_dbi dbi, MDB_pageparent *mp);
504 static int mdb_update_key(MDB_page *mp, indx_t indx, MDB_val *key);
505 static int mdb_move_node(MDB_txn *txn, MDB_dbi dbi,
506 MDB_pageparent *src, indx_t srcindx,
507 MDB_pageparent *dst, indx_t dstindx);
508 static int mdb_merge(MDB_txn *txn, MDB_dbi dbi, MDB_pageparent *src,
509 MDB_pageparent *dst);
510 static int mdb_split(MDB_txn *txn, MDB_dbi dbi, MDB_page **mpp,
511 unsigned int *newindxp, MDB_val *newkey,
512 MDB_val *newdata, pgno_t newpgno);
513 static MDB_dpage *mdb_new_page(MDB_txn *txn, MDB_dbi dbi, uint32_t flags, int num);
515 static void cursor_pop_page(MDB_cursor *cursor);
516 static MDB_ppage *cursor_push_page(MDB_cursor *cursor,
519 static int mdb_sibling(MDB_cursor *cursor, int move_right);
520 static int mdb_cursor_next(MDB_cursor *cursor,
521 MDB_val *key, MDB_val *data, MDB_cursor_op op);
522 static int mdb_cursor_prev(MDB_cursor *cursor,
523 MDB_val *key, MDB_val *data, MDB_cursor_op op);
524 static int mdb_cursor_set(MDB_cursor *cursor,
525 MDB_val *key, MDB_val *data, MDB_cursor_op op, int *exactp);
526 static int mdb_cursor_first(MDB_cursor *cursor,
527 MDB_val *key, MDB_val *data);
528 static int mdb_cursor_last(MDB_cursor *cursor,
529 MDB_val *key, MDB_val *data);
531 static void mdb_xcursor_init0(MDB_cursor *mc);
532 static void mdb_xcursor_init1(MDB_cursor *mc, MDB_page *mp, MDB_node *node);
533 static void mdb_xcursor_init2(MDB_cursor *mc);
534 static void mdb_xcursor_fini(MDB_cursor *mc);
536 static size_t mdb_leaf_size(MDB_env *env, MDB_val *key,
538 static size_t mdb_branch_size(MDB_env *env, MDB_val *key);
540 static void mdb_default_cmp(MDB_txn *txn, MDB_dbi dbi);
542 static MDB_cmp_func memncmp, memnrcmp, intcmp;
545 static SECURITY_DESCRIPTOR mdb_null_sd;
546 static SECURITY_ATTRIBUTES mdb_all_sa;
547 static int mdb_sec_inited;
551 mdb_version(int *maj, int *min, int *pat)
553 if (maj) *maj = MDB_VERSION_MAJOR;
554 if (min) *min = MDB_VERSION_MINOR;
555 if (pat) *pat = MDB_VERSION_PATCH;
556 return MDB_VERSION_STRING;
559 static char *const mdb_errstr[] = {
560 "MDB_KEYEXIST: Key/data pair already exists",
561 "MDB_NOTFOUND: No matching key/data pair found",
562 "MDB_PAGE_NOTFOUND: Requested page not found",
563 "MDB_CORRUPTED: Located page was wrong type",
564 "MDB_PANIC: Update of meta page failed",
565 "MDB_VERSION_MISMATCH: Database environment version mismatch"
569 mdb_strerror(int err)
572 return ("Successful return: 0");
574 if (err >= MDB_KEYEXIST && err <= MDB_VERSION_MISMATCH)
575 return mdb_errstr[err - MDB_KEYEXIST];
577 return strerror(err);
582 mdb_dkey(MDB_val *key, char *buf)
585 unsigned char *c = key->mv_data;
587 if (key->mv_size > MAXKEYSIZE)
590 for (i=0; i<key->mv_size; i++)
591 ptr += sprintf(ptr, "%02x", *c++);
593 sprintf(buf, "%.*s", key->mv_size, key->mv_data);
600 mdb_cmp(MDB_txn *txn, MDB_dbi dbi, const MDB_val *a, const MDB_val *b)
602 return txn->mt_dbxs[dbi].md_cmp(a, b);
606 mdb_dcmp(MDB_txn *txn, MDB_dbi dbi, const MDB_val *a, const MDB_val *b)
608 if (txn->mt_dbxs[dbi].md_dcmp)
609 return txn->mt_dbxs[dbi].md_dcmp(a, b);
611 return EINVAL; /* too bad you can't distinguish this from a valid result */
614 /* Allocate new page(s) for writing */
616 mdb_alloc_page(MDB_txn *txn, MDB_dbi dbi, MDB_page *parent, unsigned int parent_idx, int num)
619 pgno_t pgno = P_INVALID;
622 if (txn->mt_txnid > 2) {
624 if (!txn->mt_env->me_pghead && dbi != FREE_DBI &&
625 txn->mt_dbs[FREE_DBI].md_root != P_INVALID) {
626 /* See if there's anything in the free DB */
632 mpp.mp_parent = NULL;
635 mc.mc_dbi = FREE_DBI;
638 mdb_search_page(txn, FREE_DBI, NULL, &mc, 0, &mpp);
639 leaf = NODEPTR(mpp.mp_page, 0);
640 kptr = (ULONG *)NODEKEY(leaf);
644 oldest = txn->mt_txnid - 1;
645 for (i=0; i<txn->mt_env->me_txns->mti_numreaders; i++) {
646 ULONG mr = txn->mt_env->me_txns->mti_readers[i].mr_txnid;
647 if (mr && mr < oldest)
652 if (oldest > *kptr) {
653 /* It's usable, grab it.
660 mdb_read_data(txn, leaf, &data);
661 idl = (ULONG *)data.mv_data;
662 mop = malloc(sizeof(MDB_oldpages) + MDB_IDL_SIZEOF(idl) - sizeof(pgno_t));
663 mop->mo_next = txn->mt_env->me_pghead;
664 mop->mo_txnid = *kptr;
665 txn->mt_env->me_pghead = mop;
666 memcpy(mop->mo_pages, idl, MDB_IDL_SIZEOF(idl));
671 DPRINTF("IDL read txn %lu root %lu num %lu",
672 mop->mo_txnid, txn->mt_dbs[FREE_DBI].md_root, idl[0]);
673 for (i=0; i<idl[0]; i++) {
674 DPRINTF("IDL %lu", idl[i+1]);
678 /* drop this IDL from the DB */
679 top = CURSOR_TOP(&mc);
681 mc.mc_flags = C_INITIALIZED;
682 mdb_cursor_del(&mc, 0);
685 if (txn->mt_env->me_pghead) {
686 MDB_oldpages *mop = txn->mt_env->me_pghead;
688 /* FIXME: For now, always use fresh pages. We
689 * really ought to search the free list for a
694 /* peel pages off tail, so we only have to truncate the list */
695 pgno = MDB_IDL_LAST(mop->mo_pages);
696 if (MDB_IDL_IS_RANGE(mop->mo_pages)) {
698 if (mop->mo_pages[2] > mop->mo_pages[1])
699 mop->mo_pages[0] = 0;
703 if (MDB_IDL_IS_ZERO(mop->mo_pages)) {
704 txn->mt_env->me_pghead = mop->mo_next;
711 if (pgno == P_INVALID) {
712 /* DB size is maxed out */
713 if (txn->mt_next_pgno + num >= txn->mt_env->me_maxpg)
716 if (txn->mt_env->me_dpages && num == 1) {
717 dp = txn->mt_env->me_dpages;
718 txn->mt_env->me_dpages = (MDB_dpage *)dp->h.md_parent;
720 if ((dp = malloc(txn->mt_env->me_psize * num + sizeof(MDB_dhead))) == NULL)
724 dp->h.md_parent = parent;
725 dp->h.md_pi = parent_idx;
726 if (pgno == P_INVALID) {
727 dp->p.mp_pgno = txn->mt_next_pgno;
728 txn->mt_next_pgno += num;
730 dp->p.mp_pgno = pgno;
732 mid.mid = dp->p.mp_pgno;
734 mdb_mid2l_insert(txn->mt_u.dirty_list, &mid);
739 /* Touch a page: make it dirty and re-insert into tree with updated pgno.
742 mdb_touch(MDB_txn *txn, MDB_dbi dbi, MDB_pageparent *pp)
744 MDB_page *mp = pp->mp_page;
749 if (!F_ISSET(mp->mp_flags, P_DIRTY)) {
751 if ((dp = mdb_alloc_page(txn, dbi, pp->mp_parent, pp->mp_pi, 1)) == NULL)
753 DPRINTF("touched db %u page %lu -> %lu", dbi, mp->mp_pgno, dp->p.mp_pgno);
754 assert(mp->mp_pgno != dp->p.mp_pgno);
755 mdb_midl_append(txn->mt_free_pgs, mp->mp_pgno);
756 pgno = dp->p.mp_pgno;
757 memcpy(&dp->p, mp, txn->mt_env->me_psize);
760 mp->mp_flags |= P_DIRTY;
762 /* Update the page number to new touched page. */
763 if (pp->mp_parent != NULL)
764 SETPGNO(NODEPTR(pp->mp_parent, pp->mp_pi), mp->mp_pgno);
771 mdb_env_sync(MDB_env *env, int force)
774 if (force || !F_ISSET(env->me_flags, MDB_NOSYNC)) {
775 if (fdatasync(env->me_fd))
782 mdb_txn_reset0(MDB_txn *txn);
785 mdb_txn_renew0(MDB_txn *txn)
787 MDB_env *env = txn->mt_env;
789 if (txn->mt_flags & MDB_TXN_RDONLY) {
790 MDB_reader *r = pthread_getspecific(env->me_txkey);
793 pid_t pid = getpid();
794 pthread_t tid = pthread_self();
797 for (i=0; i<env->me_txns->mti_numreaders; i++)
798 if (env->me_txns->mti_readers[i].mr_pid == 0)
800 if (i == env->me_maxreaders) {
804 env->me_txns->mti_readers[i].mr_pid = pid;
805 env->me_txns->mti_readers[i].mr_tid = tid;
806 if (i >= env->me_txns->mti_numreaders)
807 env->me_txns->mti_numreaders = i+1;
809 r = &env->me_txns->mti_readers[i];
810 pthread_setspecific(env->me_txkey, r);
812 txn->mt_txnid = env->me_txns->mti_txnid;
813 txn->mt_toggle = env->me_txns->mti_me_toggle;
814 r->mr_txnid = txn->mt_txnid;
815 txn->mt_u.reader = r;
819 txn->mt_txnid = env->me_txns->mti_txnid+1;
820 txn->mt_toggle = env->me_txns->mti_me_toggle;
821 txn->mt_u.dirty_list = env->me_dirty_list;
822 txn->mt_u.dirty_list[0].mid = 0;
823 txn->mt_free_pgs = env->me_free_pgs;
824 txn->mt_free_pgs[0] = 0;
825 txn->mt_next_pgno = env->me_metas[txn->mt_toggle]->mm_last_pg+1;
829 /* Copy the DB arrays */
830 LAZY_RWLOCK_RDLOCK(&env->me_dblock);
831 txn->mt_numdbs = env->me_numdbs;
832 txn->mt_dbxs = env->me_dbxs; /* mostly static anyway */
833 memcpy(txn->mt_dbs, env->me_metas[txn->mt_toggle]->mm_dbs, 2 * sizeof(MDB_db));
834 if (txn->mt_numdbs > 2)
835 memcpy(txn->mt_dbs+2, env->me_dbs[env->me_db_toggle]+2,
836 (txn->mt_numdbs - 2) * sizeof(MDB_db));
837 LAZY_RWLOCK_UNLOCK(&env->me_dblock);
843 mdb_txn_renew(MDB_txn *txn)
850 if (txn->mt_env->me_flags & MDB_FATAL_ERROR) {
851 DPUTS("environment had fatal error, must shutdown!");
855 rc = mdb_txn_renew0(txn);
856 if (rc == MDB_SUCCESS) {
857 DPRINTF("renew txn %lu%c %p on mdbenv %p, root page %lu",
858 txn->mt_txnid, (txn->mt_flags & MDB_TXN_RDONLY) ? 'r' : 'w', txn,
859 (void *)txn->mt_env, txn->mt_dbs[MAIN_DBI].md_root);
865 mdb_txn_begin(MDB_env *env, unsigned int flags, MDB_txn **ret)
870 if (env->me_flags & MDB_FATAL_ERROR) {
871 DPUTS("environment had fatal error, must shutdown!");
874 if ((txn = calloc(1, sizeof(MDB_txn) + env->me_maxdbs * sizeof(MDB_db))) == NULL) {
875 DPRINTF("calloc: %s", strerror(ErrCode()));
878 txn->mt_dbs = (MDB_db *)(txn+1);
879 if (flags & MDB_RDONLY) {
880 txn->mt_flags |= MDB_TXN_RDONLY;
884 rc = mdb_txn_renew0(txn);
889 DPRINTF("begin txn %lu%c %p on mdbenv %p, root page %lu",
890 txn->mt_txnid, (txn->mt_flags & MDB_TXN_RDONLY) ? 'r' : 'w', txn,
891 (void *) env, txn->mt_dbs[MAIN_DBI].md_root);
898 mdb_txn_reset0(MDB_txn *txn)
900 MDB_env *env = txn->mt_env;
902 if (F_ISSET(txn->mt_flags, MDB_TXN_RDONLY)) {
903 txn->mt_u.reader->mr_txnid = 0;
909 /* return all dirty pages to dpage list */
910 for (i=1; i<=txn->mt_u.dirty_list[0].mid; i++) {
911 dp = txn->mt_u.dirty_list[i].mptr;
912 if (dp->h.md_num == 1) {
913 dp->h.md_parent = (MDB_page *)txn->mt_env->me_dpages;
914 txn->mt_env->me_dpages = dp;
916 /* large pages just get freed directly */
921 while ((mop = txn->mt_env->me_pghead)) {
922 txn->mt_env->me_pghead = mop->mo_next;
927 for (i=2; i<env->me_numdbs; i++)
928 env->me_dbxs[i].md_dirty = 0;
934 mdb_txn_reset(MDB_txn *txn)
939 DPRINTF("reset txn %lu%c %p on mdbenv %p, root page %lu",
940 txn->mt_txnid, (txn->mt_flags & MDB_TXN_RDONLY) ? 'r' : 'w', txn,
941 (void *)txn->mt_env, txn->mt_dbs[MAIN_DBI].md_root);
947 mdb_txn_abort(MDB_txn *txn)
952 DPRINTF("abort txn %lu%c %p on mdbenv %p, root page %lu",
953 txn->mt_txnid, (txn->mt_flags & MDB_TXN_RDONLY) ? 'r' : 'w', txn,
954 (void *)txn->mt_env, txn->mt_dbs[MAIN_DBI].md_root);
961 mdb_txn_commit(MDB_txn *txn)
973 assert(txn->mt_env != NULL);
977 if (F_ISSET(txn->mt_flags, MDB_TXN_RDONLY)) {
982 if (txn != env->me_txn) {
983 DPUTS("attempt to commit unknown transaction");
988 if (F_ISSET(txn->mt_flags, MDB_TXN_ERROR)) {
989 DPUTS("error flag is set, can't commit");
994 if (!txn->mt_u.dirty_list[0].mid)
997 DPRINTF("committing txn %lu %p on mdbenv %p, root page %lu",
998 txn->mt_txnid, txn, (void *)env, txn->mt_dbs[MAIN_DBI].md_root);
1001 mc.mc_dbi = FREE_DBI;
1004 /* should only be one record now */
1005 if (env->me_pghead) {
1008 /* make sure first page of freeDB is touched and on freelist */
1009 mpp.mp_parent = NULL;
1012 mdb_search_page(txn, FREE_DBI, NULL, &mc, 1, &mpp);
1014 /* save to free list */
1015 if (!MDB_IDL_IS_ZERO(txn->mt_free_pgs)) {
1020 /* make sure last page of freeDB is touched and on freelist */
1021 key.mv_size = MAXKEYSIZE+1;
1023 mpp.mp_parent = NULL;
1026 mdb_search_page(txn, FREE_DBI, &key, &mc, 1, &mpp);
1028 mdb_midl_sort(txn->mt_free_pgs);
1032 ULONG *idl = txn->mt_free_pgs;
1033 DPRINTF("IDL write txn %lu root %lu num %lu",
1034 txn->mt_txnid, txn->mt_dbs[FREE_DBI].md_root, idl[0]);
1035 for (i=0; i<idl[0]; i++) {
1036 DPRINTF("IDL %lu", idl[i+1]);
1040 /* write to last page of freeDB */
1041 key.mv_size = sizeof(pgno_t);
1042 key.mv_data = (char *)&txn->mt_txnid;
1043 data.mv_data = txn->mt_free_pgs;
1044 /* The free list can still grow during this call,
1045 * despite the pre-emptive touches above. So check
1046 * and make sure the entire thing got written.
1049 i = txn->mt_free_pgs[0];
1050 data.mv_size = MDB_IDL_SIZEOF(txn->mt_free_pgs);
1051 rc = mdb_cursor_put(&mc, &key, &data, 0);
1056 } while (i != txn->mt_free_pgs[0]);
1058 /* should only be one record now */
1059 if (env->me_pghead) {
1063 mop = env->me_pghead;
1064 key.mv_size = sizeof(pgno_t);
1065 key.mv_data = (char *)&mop->mo_txnid;
1066 data.mv_size = MDB_IDL_SIZEOF(mop->mo_pages);
1067 data.mv_data = mop->mo_pages;
1068 mdb_cursor_put(&mc, &key, &data, 0);
1069 free(env->me_pghead);
1070 env->me_pghead = NULL;
1073 /* Update DB root pointers. Their pages have already been
1074 * touched so this is all in-place and cannot fail.
1078 data.mv_size = sizeof(MDB_db);
1080 mc.mc_dbi = MAIN_DBI;
1082 for (i = 2; i < txn->mt_numdbs; i++) {
1083 if (txn->mt_dbxs[i].md_dirty) {
1084 data.mv_data = &txn->mt_dbs[i];
1085 mdb_cursor_put(&mc, &txn->mt_dbxs[i].md_name, &data, 0);
1090 /* Commit up to MDB_COMMIT_PAGES dirty pages to disk until done.
1096 /* Windows actually supports scatter/gather I/O, but only on
1097 * unbuffered file handles. Since we're relying on the OS page
1098 * cache for all our data, that's self-defeating. So we just
1099 * write pages one at a time. We use the ov structure to set
1100 * the write offset, to at least save the overhead of a Seek
1104 memset(&ov, 0, sizeof(ov));
1105 for (; i<=txn->mt_u.dirty_list[0].mid; i++) {
1106 dp = txn->mt_u.dirty_list[i].mptr;
1107 DPRINTF("committing page %lu", dp->p.mp_pgno);
1108 size = dp->p.mp_pgno * env->me_psize;
1109 ov.Offset = size & 0xffffffff;
1110 ov.OffsetHigh = size >> 16;
1111 ov.OffsetHigh >>= 16;
1112 /* clear dirty flag */
1113 dp->p.mp_flags &= ~P_DIRTY;
1114 rc = WriteFile(env->me_fd, &dp->p, env->me_psize * dp->h.md_num, NULL, &ov);
1117 DPRINTF("WriteFile: %d", n);
1124 struct iovec iov[MDB_COMMIT_PAGES];
1128 for (; i<=txn->mt_u.dirty_list[0].mid; i++) {
1129 dp = txn->mt_u.dirty_list[i].mptr;
1130 if (dp->p.mp_pgno != next) {
1132 DPRINTF("committing %u dirty pages", n);
1133 rc = writev(env->me_fd, iov, n);
1137 DPUTS("short write, filesystem full?");
1139 DPRINTF("writev: %s", strerror(n));
1146 lseek(env->me_fd, dp->p.mp_pgno * env->me_psize, SEEK_SET);
1147 next = dp->p.mp_pgno;
1149 DPRINTF("committing page %lu", dp->p.mp_pgno);
1150 iov[n].iov_len = env->me_psize * dp->h.md_num;
1151 iov[n].iov_base = &dp->p;
1152 size += iov[n].iov_len;
1153 next = dp->p.mp_pgno + dp->h.md_num;
1154 /* clear dirty flag */
1155 dp->p.mp_flags &= ~P_DIRTY;
1156 if (++n >= MDB_COMMIT_PAGES) {
1166 DPRINTF("committing %u dirty pages", n);
1167 rc = writev(env->me_fd, iov, n);
1171 DPUTS("short write, filesystem full?");
1173 DPRINTF("writev: %s", strerror(n));
1180 /* Drop the dirty pages.
1182 for (i=1; i<=txn->mt_u.dirty_list[0].mid; i++) {
1183 dp = txn->mt_u.dirty_list[i].mptr;
1184 if (dp->h.md_num == 1) {
1185 dp->h.md_parent = (MDB_page *)txn->mt_env->me_dpages;
1186 txn->mt_env->me_dpages = dp;
1190 txn->mt_u.dirty_list[i].mid = 0;
1192 txn->mt_u.dirty_list[0].mid = 0;
1194 if ((n = mdb_env_sync(env, 0)) != 0 ||
1195 (n = mdb_env_write_meta(txn)) != MDB_SUCCESS) {
1202 /* update the DB tables */
1204 int toggle = !env->me_db_toggle;
1207 ip = &env->me_dbs[toggle][2];
1208 jp = &txn->mt_dbs[2];
1209 LAZY_RWLOCK_WRLOCK(&env->me_dblock);
1210 for (i = 2; i < txn->mt_numdbs; i++) {
1211 if (ip->md_root != jp->md_root)
1216 for (i = 2; i < txn->mt_numdbs; i++) {
1217 if (txn->mt_dbxs[i].md_dirty)
1218 txn->mt_dbxs[i].md_dirty = 0;
1220 env->me_db_toggle = toggle;
1221 env->me_numdbs = txn->mt_numdbs;
1222 LAZY_RWLOCK_UNLOCK(&env->me_dblock);
1225 UNLOCK_MUTEX_W(env);
1232 mdb_env_read_header(MDB_env *env, MDB_meta *meta)
1234 char page[PAGESIZE];
1239 /* We don't know the page size yet, so use a minimum value.
1243 if (!ReadFile(env->me_fd, page, PAGESIZE, (DWORD *)&rc, NULL) || rc == 0)
1245 if ((rc = read(env->me_fd, page, PAGESIZE)) == 0)
1250 else if (rc != PAGESIZE) {
1254 DPRINTF("read: %s", strerror(err));
1258 p = (MDB_page *)page;
1260 if (!F_ISSET(p->mp_flags, P_META)) {
1261 DPRINTF("page %lu not a meta page", p->mp_pgno);
1266 if (m->mm_magic != MDB_MAGIC) {
1267 DPUTS("meta has invalid magic");
1271 if (m->mm_version != MDB_VERSION) {
1272 DPRINTF("database is version %u, expected version %u",
1273 m->mm_version, MDB_VERSION);
1274 return MDB_VERSION_MISMATCH;
1277 memcpy(meta, m, sizeof(*m));
1282 mdb_env_init_meta(MDB_env *env, MDB_meta *meta)
1289 DPUTS("writing new meta page");
1293 meta->mm_magic = MDB_MAGIC;
1294 meta->mm_version = MDB_VERSION;
1295 meta->mm_psize = psize;
1296 meta->mm_last_pg = 1;
1297 meta->mm_flags = env->me_flags & 0xffff;
1298 meta->mm_flags |= MDB_INTEGERKEY;
1299 meta->mm_dbs[0].md_root = P_INVALID;
1300 meta->mm_dbs[1].md_root = P_INVALID;
1302 p = calloc(2, psize);
1304 p->mp_flags = P_META;
1307 memcpy(m, meta, sizeof(*meta));
1309 q = (MDB_page *)((char *)p + psize);
1312 q->mp_flags = P_META;
1315 memcpy(m, meta, sizeof(*meta));
1320 rc = WriteFile(env->me_fd, p, psize * 2, &len, NULL);
1321 rc = (len == psize * 2) ? MDB_SUCCESS : ErrCode();
1324 rc = write(env->me_fd, p, psize * 2);
1325 rc = (rc == (int)psize * 2) ? MDB_SUCCESS : ErrCode();
1332 mdb_env_write_meta(MDB_txn *txn)
1335 MDB_meta meta, metab;
1337 int rc, len, toggle;
1343 assert(txn != NULL);
1344 assert(txn->mt_env != NULL);
1346 toggle = !txn->mt_toggle;
1347 DPRINTF("writing meta page %d for root page %lu",
1348 toggle, txn->mt_dbs[MAIN_DBI].md_root);
1352 metab.mm_txnid = env->me_metas[toggle]->mm_txnid;
1353 metab.mm_last_pg = env->me_metas[toggle]->mm_last_pg;
1355 ptr = (char *)&meta;
1356 off = offsetof(MDB_meta, mm_dbs[0].md_depth);
1357 len = sizeof(MDB_meta) - off;
1360 meta.mm_dbs[0] = txn->mt_dbs[0];
1361 meta.mm_dbs[1] = txn->mt_dbs[1];
1362 meta.mm_last_pg = txn->mt_next_pgno - 1;
1363 meta.mm_txnid = txn->mt_txnid;
1366 off += env->me_psize;
1369 /* Write to the SYNC fd */
1372 memset(&ov, 0, sizeof(ov));
1374 WriteFile(env->me_mfd, ptr, len, (DWORD *)&rc, &ov);
1377 rc = pwrite(env->me_mfd, ptr, len, off);
1382 DPUTS("write failed, disk error?");
1383 /* On a failure, the pagecache still contains the new data.
1384 * Write some old data back, to prevent it from being used.
1385 * Use the non-SYNC fd; we know it will fail anyway.
1387 meta.mm_last_pg = metab.mm_last_pg;
1388 meta.mm_txnid = metab.mm_txnid;
1390 WriteFile(env->me_fd, ptr, len, NULL, &ov);
1392 r2 = pwrite(env->me_fd, ptr, len, off);
1394 env->me_flags |= MDB_FATAL_ERROR;
1397 /* Memory ordering issues are irrelevant; since the entire writer
1398 * is wrapped by wmutex, all of these changes will become visible
1399 * after the wmutex is unlocked. Since the DB is multi-version,
1400 * readers will get consistent data regardless of how fresh or
1401 * how stale their view of these values is.
1403 LAZY_MUTEX_LOCK(&env->me_txns->mti_mutex);
1404 txn->mt_env->me_txns->mti_me_toggle = toggle;
1405 txn->mt_env->me_txns->mti_txnid = txn->mt_txnid;
1406 LAZY_MUTEX_UNLOCK(&env->me_txns->mti_mutex);
1412 mdb_env_read_meta(MDB_env *env, int *which)
1416 assert(env != NULL);
1418 if (env->me_metas[0]->mm_txnid < env->me_metas[1]->mm_txnid)
1421 DPRINTF("Using meta page %d", toggle);
1428 mdb_env_create(MDB_env **env)
1432 e = calloc(1, sizeof(MDB_env));
1433 if (!e) return ENOMEM;
1435 e->me_maxreaders = DEFAULT_READERS;
1437 e->me_fd = INVALID_HANDLE_VALUE;
1438 e->me_lfd = INVALID_HANDLE_VALUE;
1439 e->me_mfd = INVALID_HANDLE_VALUE;
1445 mdb_env_set_mapsize(MDB_env *env, size_t size)
1449 env->me_mapsize = size;
1454 mdb_env_set_maxdbs(MDB_env *env, int dbs)
1458 env->me_maxdbs = dbs;
1463 mdb_env_set_maxreaders(MDB_env *env, int readers)
1467 env->me_maxreaders = readers;
1472 mdb_env_get_maxreaders(MDB_env *env, int *readers)
1474 if (!env || !readers)
1476 *readers = env->me_maxreaders;
1481 mdb_env_open2(MDB_env *env, unsigned int flags)
1483 int i, newenv = 0, toggle;
1487 env->me_flags = flags;
1489 memset(&meta, 0, sizeof(meta));
1491 if ((i = mdb_env_read_header(env, &meta)) != 0) {
1494 DPUTS("new mdbenv");
1498 if (!env->me_mapsize) {
1499 env->me_mapsize = newenv ? DEFAULT_MAPSIZE : meta.mm_mapsize;
1505 LONG sizelo, sizehi;
1506 sizelo = env->me_mapsize & 0xffffffff;
1507 sizehi = env->me_mapsize >> 16; /* pointless on WIN32, only needed on W64 */
1509 /* Windows won't create mappings for zero length files.
1510 * Just allocate the maxsize right now.
1513 SetFilePointer(env->me_fd, sizelo, sizehi ? &sizehi : NULL, 0);
1514 if (!SetEndOfFile(env->me_fd))
1516 SetFilePointer(env->me_fd, 0, NULL, 0);
1518 mh = CreateFileMapping(env->me_fd, NULL, PAGE_READONLY,
1519 sizehi, sizelo, NULL);
1522 env->me_map = MapViewOfFileEx(mh, FILE_MAP_READ, 0, 0, env->me_mapsize,
1530 if (meta.mm_address && (flags & MDB_FIXEDMAP))
1532 env->me_map = mmap(meta.mm_address, env->me_mapsize, PROT_READ, i,
1534 if (env->me_map == MAP_FAILED)
1539 meta.mm_mapsize = env->me_mapsize;
1540 if (flags & MDB_FIXEDMAP)
1541 meta.mm_address = env->me_map;
1542 i = mdb_env_init_meta(env, &meta);
1543 if (i != MDB_SUCCESS) {
1544 munmap(env->me_map, env->me_mapsize);
1548 env->me_psize = meta.mm_psize;
1550 env->me_maxpg = env->me_mapsize / env->me_psize;
1552 p = (MDB_page *)env->me_map;
1553 env->me_metas[0] = METADATA(p);
1554 env->me_metas[1] = (MDB_meta *)((char *)env->me_metas[0] + meta.mm_psize);
1556 if ((i = mdb_env_read_meta(env, &toggle)) != 0)
1559 DPRINTF("opened database version %u, pagesize %u",
1560 env->me_metas[toggle]->mm_version, env->me_psize);
1561 DPRINTF("depth: %u", env->me_metas[toggle]->mm_dbs[MAIN_DBI].md_depth);
1562 DPRINTF("entries: %lu", env->me_metas[toggle]->mm_dbs[MAIN_DBI].md_entries);
1563 DPRINTF("branch pages: %lu", env->me_metas[toggle]->mm_dbs[MAIN_DBI].md_branch_pages);
1564 DPRINTF("leaf pages: %lu", env->me_metas[toggle]->mm_dbs[MAIN_DBI].md_leaf_pages);
1565 DPRINTF("overflow pages: %lu", env->me_metas[toggle]->mm_dbs[MAIN_DBI].md_overflow_pages);
1566 DPRINTF("root: %lu", env->me_metas[toggle]->mm_dbs[MAIN_DBI].md_root);
1572 /* Windows doesn't support destructor callbacks for thread-specific storage */
1574 mdb_env_reader_dest(void *ptr)
1576 MDB_reader *reader = ptr;
1578 reader->mr_txnid = 0;
1584 /* downgrade the exclusive lock on the region back to shared */
1586 mdb_env_share_locks(MDB_env *env)
1590 if (env->me_metas[0]->mm_txnid < env->me_metas[1]->mm_txnid)
1592 env->me_txns->mti_me_toggle = toggle;
1593 env->me_txns->mti_txnid = env->me_metas[toggle]->mm_txnid;
1598 /* First acquire a shared lock. The Unlock will
1599 * then release the existing exclusive lock.
1601 memset(&ov, 0, sizeof(ov));
1602 LockFileEx(env->me_lfd, 0, 0, 1, 0, &ov);
1603 UnlockFile(env->me_lfd, 0, 0, 1, 0);
1607 struct flock lock_info;
1608 /* The shared lock replaces the existing lock */
1609 memset((void *)&lock_info, 0, sizeof(lock_info));
1610 lock_info.l_type = F_RDLCK;
1611 lock_info.l_whence = SEEK_SET;
1612 lock_info.l_start = 0;
1613 lock_info.l_len = 1;
1614 fcntl(env->me_lfd, F_SETLK, &lock_info);
1620 mdb_env_setup_locks(MDB_env *env, char *lpath, int mode, int *excl)
1628 if ((env->me_lfd = CreateFile(lpath, GENERIC_READ|GENERIC_WRITE,
1629 FILE_SHARE_READ|FILE_SHARE_WRITE, NULL, OPEN_ALWAYS,
1630 FILE_ATTRIBUTE_NORMAL, NULL)) == INVALID_HANDLE_VALUE) {
1634 /* Try to get exclusive lock. If we succeed, then
1635 * nobody is using the lock region and we should initialize it.
1638 if (LockFile(env->me_lfd, 0, 0, 1, 0)) {
1642 memset(&ov, 0, sizeof(ov));
1643 if (!LockFileEx(env->me_lfd, 0, 0, 1, 0, &ov)) {
1649 size = GetFileSize(env->me_lfd, NULL);
1651 if ((env->me_lfd = open(lpath, O_RDWR|O_CREAT, mode)) == -1) {
1655 /* Try to get exclusive lock. If we succeed, then
1656 * nobody is using the lock region and we should initialize it.
1659 struct flock lock_info;
1660 memset((void *)&lock_info, 0, sizeof(lock_info));
1661 lock_info.l_type = F_WRLCK;
1662 lock_info.l_whence = SEEK_SET;
1663 lock_info.l_start = 0;
1664 lock_info.l_len = 1;
1665 rc = fcntl(env->me_lfd, F_SETLK, &lock_info);
1669 lock_info.l_type = F_RDLCK;
1670 rc = fcntl(env->me_lfd, F_SETLKW, &lock_info);
1677 size = lseek(env->me_lfd, 0, SEEK_END);
1679 rsize = (env->me_maxreaders-1) * sizeof(MDB_reader) + sizeof(MDB_txninfo);
1680 if (size < rsize && *excl) {
1682 SetFilePointer(env->me_lfd, rsize, NULL, 0);
1683 if (!SetEndOfFile(env->me_lfd)) {
1688 if (ftruncate(env->me_lfd, rsize) != 0) {
1695 size = rsize - sizeof(MDB_txninfo);
1696 env->me_maxreaders = size/sizeof(MDB_reader) + 1;
1701 mh = CreateFileMapping(env->me_lfd, NULL, PAGE_READWRITE,
1707 env->me_txns = MapViewOfFileEx(mh, FILE_MAP_WRITE, 0, 0, rsize, NULL);
1709 if (!env->me_txns) {
1715 env->me_txns = mmap(0, rsize, PROT_READ|PROT_WRITE, MAP_SHARED,
1717 if (env->me_txns == MAP_FAILED) {
1725 if (!mdb_sec_inited) {
1726 InitializeSecurityDescriptor(&mdb_null_sd,
1727 SECURITY_DESCRIPTOR_REVISION);
1728 SetSecurityDescriptorDacl(&mdb_null_sd, TRUE, 0, FALSE);
1729 mdb_all_sa.nLength = sizeof(SECURITY_ATTRIBUTES);
1730 mdb_all_sa.bInheritHandle = FALSE;
1731 mdb_all_sa.lpSecurityDescriptor = &mdb_null_sd;
1734 /* FIXME: only using up to 20 characters of the env path here,
1735 * probably not enough to assure uniqueness...
1737 sprintf(env->me_txns->mti_rmname, "Global\\MDBr%.20s", lpath);
1738 ptr = env->me_txns->mti_rmname + sizeof("Global\\MDBr");
1739 while ((ptr = strchr(ptr, '\\')))
1741 env->me_rmutex = CreateMutex(&mdb_all_sa, FALSE, env->me_txns->mti_rmname);
1742 if (!env->me_rmutex) {
1746 sprintf(env->me_txns->mti_rmname, "Global\\MDBw%.20s", lpath);
1747 ptr = env->me_txns->mti_rmname + sizeof("Global\\MDBw");
1748 while ((ptr = strchr(ptr, '\\')))
1750 env->me_wmutex = CreateMutex(&mdb_all_sa, FALSE, env->me_txns->mti_rmname);
1751 if (!env->me_wmutex) {
1756 pthread_mutexattr_t mattr;
1758 pthread_mutexattr_init(&mattr);
1759 rc = pthread_mutexattr_setpshared(&mattr, PTHREAD_PROCESS_SHARED);
1763 pthread_mutex_init(&env->me_txns->mti_mutex, &mattr);
1764 pthread_mutex_init(&env->me_txns->mti_wmutex, &mattr);
1766 env->me_txns->mti_version = MDB_VERSION;
1767 env->me_txns->mti_magic = MDB_MAGIC;
1768 env->me_txns->mti_txnid = 0;
1769 env->me_txns->mti_numreaders = 0;
1770 env->me_txns->mti_me_toggle = 0;
1773 if (env->me_txns->mti_magic != MDB_MAGIC) {
1774 DPUTS("lock region has invalid magic");
1778 if (env->me_txns->mti_version != MDB_VERSION) {
1779 DPRINTF("lock region is version %u, expected version %u",
1780 env->me_txns->mti_version, MDB_VERSION);
1781 rc = MDB_VERSION_MISMATCH;
1785 if (rc != EACCES && rc != EAGAIN) {
1789 env->me_rmutex = OpenMutex(SYNCHRONIZE, FALSE, env->me_txns->mti_rmname);
1790 if (!env->me_rmutex) {
1794 env->me_wmutex = OpenMutex(SYNCHRONIZE, FALSE, env->me_txns->mti_wmname);
1795 if (!env->me_wmutex) {
1805 env->me_lfd = INVALID_HANDLE_VALUE;
1810 #define LOCKNAME "/lock.mdb"
1811 #define DATANAME "/data.mdb"
1813 mdb_env_open(MDB_env *env, const char *path, unsigned int flags, mode_t mode)
1815 int oflags, rc, len, excl;
1816 char *lpath, *dpath;
1819 lpath = malloc(len + sizeof(LOCKNAME) + len + sizeof(DATANAME));
1822 dpath = lpath + len + sizeof(LOCKNAME);
1823 sprintf(lpath, "%s" LOCKNAME, path);
1824 sprintf(dpath, "%s" DATANAME, path);
1826 rc = mdb_env_setup_locks(env, lpath, mode, &excl);
1831 if (F_ISSET(flags, MDB_RDONLY)) {
1832 oflags = GENERIC_READ;
1833 len = OPEN_EXISTING;
1835 oflags = GENERIC_READ|GENERIC_WRITE;
1838 mode = FILE_ATTRIBUTE_NORMAL;
1839 if ((env->me_fd = CreateFile(dpath, oflags, FILE_SHARE_READ|FILE_SHARE_WRITE,
1840 NULL, len, mode, NULL)) == INVALID_HANDLE_VALUE) {
1845 if (F_ISSET(flags, MDB_RDONLY))
1848 oflags = O_RDWR | O_CREAT;
1850 if ((env->me_fd = open(dpath, oflags, mode)) == -1) {
1856 if ((rc = mdb_env_open2(env, flags)) == MDB_SUCCESS) {
1857 /* synchronous fd for meta writes */
1859 if (!(flags & (MDB_RDONLY|MDB_NOSYNC)))
1860 mode |= FILE_FLAG_WRITE_THROUGH;
1861 if ((env->me_mfd = CreateFile(dpath, oflags, FILE_SHARE_READ|FILE_SHARE_WRITE,
1862 NULL, len, mode, NULL)) == INVALID_HANDLE_VALUE) {
1867 if (!(flags & (MDB_RDONLY|MDB_NOSYNC)))
1868 oflags |= MDB_DSYNC;
1869 if ((env->me_mfd = open(dpath, oflags, mode)) == -1) {
1874 env->me_path = strdup(path);
1875 DPRINTF("opened dbenv %p", (void *) env);
1876 pthread_key_create(&env->me_txkey, mdb_env_reader_dest);
1877 LAZY_RWLOCK_INIT(&env->me_dblock, NULL);
1879 mdb_env_share_locks(env);
1880 env->me_dbxs = calloc(env->me_maxdbs, sizeof(MDB_dbx));
1881 env->me_dbs[0] = calloc(env->me_maxdbs, sizeof(MDB_db));
1882 env->me_dbs[1] = calloc(env->me_maxdbs, sizeof(MDB_db));
1888 if (env->me_fd != INVALID_HANDLE_VALUE) {
1890 env->me_fd = INVALID_HANDLE_VALUE;
1892 if (env->me_lfd != INVALID_HANDLE_VALUE) {
1894 env->me_lfd = INVALID_HANDLE_VALUE;
1902 mdb_env_close(MDB_env *env)
1909 while (env->me_dpages) {
1910 dp = env->me_dpages;
1911 env->me_dpages = (MDB_dpage *)dp->h.md_parent;
1915 free(env->me_dbs[1]);
1916 free(env->me_dbs[0]);
1920 LAZY_RWLOCK_DESTROY(&env->me_dblock);
1921 pthread_key_delete(env->me_txkey);
1924 munmap(env->me_map, env->me_mapsize);
1929 pid_t pid = getpid();
1931 for (i=0; i<env->me_txns->mti_numreaders; i++)
1932 if (env->me_txns->mti_readers[i].mr_pid == pid)
1933 env->me_txns->mti_readers[i].mr_pid = 0;
1934 munmap(env->me_txns, (env->me_maxreaders-1)*sizeof(MDB_reader)+sizeof(MDB_txninfo));
1941 intcmp(const MDB_val *a, const MDB_val *b)
1943 if (a->mv_size == sizeof(long))
1945 unsigned long *la, *lb;
1950 unsigned int *ia, *ib;
1958 memncmp(const MDB_val *a, const MDB_val *b)
1964 len_diff = a->mv_size - b->mv_size;
1967 diff = memcmp(a->mv_data, b->mv_data, len);
1968 return diff ? diff : len_diff;
1972 memnrcmp(const MDB_val *a, const MDB_val *b)
1974 const unsigned char *p1, *p2, *p1_lim;
1977 if (b->mv_size == 0)
1978 return a->mv_size != 0;
1979 if (a->mv_size == 0)
1982 p1 = (const unsigned char *)a->mv_data + a->mv_size - 1;
1983 p2 = (const unsigned char *)b->mv_data + b->mv_size - 1;
1985 len_diff = a->mv_size - b->mv_size;
1987 p1_lim = p1 - a->mv_size;
1989 p1_lim = p1 - b->mv_size;
1991 while (p1 > p1_lim) {
2001 /* Search for key within a leaf page, using binary search.
2002 * Returns the smallest entry larger or equal to the key.
2003 * If exactp is non-null, stores whether the found entry was an exact match
2004 * in *exactp (1 or 0).
2005 * If kip is non-null, stores the index of the found entry in *kip.
2006 * If no entry larger or equal to the key is found, returns NULL.
2009 mdb_search_node(MDB_txn *txn, MDB_dbi dbi, MDB_page *mp, MDB_val *key,
2010 int *exactp, unsigned int *kip)
2012 unsigned int i = 0, nkeys;
2015 MDB_node *node = NULL;
2020 nkeys = NUMKEYS(mp);
2022 DPRINTF("searching %u keys in %s page %lu",
2023 nkeys, IS_LEAF(mp) ? "leaf" : "branch",
2028 low = IS_LEAF(mp) ? 0 : 1;
2030 cmp = txn->mt_dbxs[dbi].md_cmp;
2032 nodekey.mv_size = txn->mt_dbs[dbi].md_pad;
2033 node = NODEPTR(mp, 0); /* fake */
2035 while (low <= high) {
2036 i = (low + high) >> 1;
2039 nodekey.mv_data = LEAF2KEY(mp, i, nodekey.mv_size);
2041 node = NODEPTR(mp, i);
2043 nodekey.mv_size = node->mn_ksize;
2044 nodekey.mv_data = NODEKEY(node);
2047 rc = cmp(key, &nodekey);
2051 DPRINTF("found leaf index %u [%s], rc = %i",
2052 i, DKEY(&nodekey), rc);
2054 DPRINTF("found branch index %u [%s -> %lu], rc = %i",
2055 i, DKEY(&nodekey), NODEPGNO(node), rc);
2066 if (rc > 0) { /* Found entry is less than the key. */
2067 i++; /* Skip to get the smallest entry larger than key. */
2070 *exactp = (rc == 0);
2071 if (kip) /* Store the key index if requested. */
2074 /* There is no entry larger or equal to the key. */
2077 /* nodeptr is fake for LEAF2 */
2082 cursor_pop_page(MDB_cursor *cursor)
2086 if (cursor->mc_snum) {
2087 top = CURSOR_TOP(cursor);
2090 DPRINTF("popped page %lu off db %u cursor %p", top->mp_page->mp_pgno,
2091 cursor->mc_dbi, (void *) cursor);
2096 cursor_push_page(MDB_cursor *cursor, MDB_page *mp)
2100 DPRINTF("pushing page %lu on db %u cursor %p", mp->mp_pgno,
2101 cursor->mc_dbi, (void *) cursor);
2103 assert(cursor->mc_snum < CURSOR_STACK);
2105 ppage = &cursor->mc_stack[cursor->mc_snum++];
2106 ppage->mp_page = mp;
2112 mdb_get_page(MDB_txn *txn, pgno_t pgno, MDB_page **ret)
2116 if (!F_ISSET(txn->mt_flags, MDB_TXN_RDONLY) && txn->mt_u.dirty_list[0].mid) {
2119 x = mdb_mid2l_search(txn->mt_u.dirty_list, pgno);
2120 if (x <= txn->mt_u.dirty_list[0].mid && txn->mt_u.dirty_list[x].mid == pgno) {
2121 dp = txn->mt_u.dirty_list[x].mptr;
2126 if (pgno <= txn->mt_env->me_metas[txn->mt_toggle]->mm_last_pg)
2127 p = (MDB_page *)(txn->mt_env->me_map + txn->mt_env->me_psize * pgno);
2131 DPRINTF("page %lu not found", pgno);
2134 return (p != NULL) ? MDB_SUCCESS : MDB_PAGE_NOTFOUND;
2138 mdb_search_page_root(MDB_txn *txn, MDB_dbi dbi, MDB_val *key,
2139 MDB_cursor *cursor, int modify, MDB_pageparent *mpp)
2141 MDB_page *mp = mpp->mp_page;
2145 if (cursor && cursor_push_page(cursor, mp) == NULL)
2148 while (IS_BRANCH(mp)) {
2152 DPRINTF("branch page %lu has %u keys", mp->mp_pgno, NUMKEYS(mp));
2153 assert(NUMKEYS(mp) > 1);
2154 DPRINTF("found index 0 to page %lu", NODEPGNO(NODEPTR(mp, 0)));
2156 if (key == NULL) /* Initialize cursor to first page. */
2158 else if (key->mv_size > MAXKEYSIZE && key->mv_data == NULL) {
2159 /* cursor to last page */
2163 node = mdb_search_node(txn, dbi, mp, key, &exact, &i);
2165 i = NUMKEYS(mp) - 1;
2173 DPRINTF("following index %u for key [%s]",
2175 assert(i < NUMKEYS(mp));
2176 node = NODEPTR(mp, i);
2179 CURSOR_TOP(cursor)->mp_ki = i;
2181 mpp->mp_parent = mp;
2182 if ((rc = mdb_get_page(txn, NODEPGNO(node), &mp)))
2187 if (cursor && cursor_push_page(cursor, mp) == NULL)
2192 if ((rc = mdb_touch(txn, dbi, mpp)) != 0)
2194 dh = ((MDB_dhead *)mpp->mp_page)-1;
2195 dh->md_parent = mpp->mp_parent;
2196 dh->md_pi = mpp->mp_pi;
2203 DPRINTF("internal error, index points to a %02X page!?",
2205 return MDB_CORRUPTED;
2208 DPRINTF("found leaf page %lu for key [%s]", mp->mp_pgno,
2209 key ? DKEY(key) : NULL);
2214 /* Search for the page a given key should be in.
2215 * Stores a pointer to the found page in *mpp.
2216 * If key is NULL, search for the lowest page (used by mdb_cursor_first).
2217 * If cursor is non-null, pushes parent pages on the cursor stack.
2218 * If modify is true, visited pages are updated with new page numbers.
2221 mdb_search_page(MDB_txn *txn, MDB_dbi dbi, MDB_val *key,
2222 MDB_cursor *cursor, int modify, MDB_pageparent *mpp)
2227 /* Choose which root page to start with. If a transaction is given
2228 * use the root page from the transaction, otherwise read the last
2229 * committed root page.
2231 if (F_ISSET(txn->mt_flags, MDB_TXN_ERROR)) {
2232 DPUTS("transaction has failed, must abort");
2235 root = txn->mt_dbs[dbi].md_root;
2237 if (root == P_INVALID) { /* Tree is empty. */
2238 DPUTS("tree is empty");
2239 return MDB_NOTFOUND;
2242 if ((rc = mdb_get_page(txn, root, &mpp->mp_page)))
2245 DPRINTF("db %u root page %lu has flags 0x%X",
2246 dbi, root, mpp->mp_page->mp_flags);
2249 /* For sub-databases, update main root first */
2250 if (dbi > MAIN_DBI && !txn->mt_dbxs[dbi].md_dirty) {
2252 rc = mdb_search_page(txn, MAIN_DBI, &txn->mt_dbxs[dbi].md_name,
2256 txn->mt_dbxs[dbi].md_dirty = 1;
2258 if (!F_ISSET(mpp->mp_page->mp_flags, P_DIRTY)) {
2259 mpp->mp_parent = NULL;
2261 if ((rc = mdb_touch(txn, dbi, mpp)))
2263 txn->mt_dbs[dbi].md_root = mpp->mp_page->mp_pgno;
2267 return mdb_search_page_root(txn, dbi, key, cursor, modify, mpp);
2271 mdb_read_data(MDB_txn *txn, MDB_node *leaf, MDB_val *data)
2273 MDB_page *omp; /* overflow mpage */
2277 if (!F_ISSET(leaf->mn_flags, F_BIGDATA)) {
2278 data->mv_size = NODEDSZ(leaf);
2279 data->mv_data = NODEDATA(leaf);
2283 /* Read overflow data.
2285 data->mv_size = NODEDSZ(leaf);
2286 memcpy(&pgno, NODEDATA(leaf), sizeof(pgno));
2287 if ((rc = mdb_get_page(txn, pgno, &omp))) {
2288 DPRINTF("read overflow page %lu failed", pgno);
2291 data->mv_data = METADATA(omp);
2297 mdb_get(MDB_txn *txn, MDB_dbi dbi,
2298 MDB_val *key, MDB_val *data)
2307 DPRINTF("===> get db %u key [%s]", dbi, DKEY(key));
2309 if (txn == NULL || !dbi || dbi >= txn->mt_numdbs)
2312 if (key->mv_size == 0 || key->mv_size > MAXKEYSIZE) {
2319 if (txn->mt_dbs[dbi].md_flags & MDB_DUPSORT) {
2320 mc.mc_xcursor = &mx;
2321 mdb_xcursor_init0(&mc);
2323 mc.mc_xcursor = NULL;
2325 return mdb_cursor_set(&mc, key, data, MDB_SET, &exact);
2329 mdb_sibling(MDB_cursor *cursor, int move_right)
2336 if (cursor->mc_snum < 2) {
2337 return MDB_NOTFOUND; /* root has no siblings */
2339 parent = CURSOR_PARENT(cursor);
2341 DPRINTF("parent page is page %lu, index %u",
2342 parent->mp_page->mp_pgno, parent->mp_ki);
2344 cursor_pop_page(cursor);
2345 if (move_right ? (parent->mp_ki + 1 >= NUMKEYS(parent->mp_page))
2346 : (parent->mp_ki == 0)) {
2347 DPRINTF("no more keys left, moving to %s sibling",
2348 move_right ? "right" : "left");
2349 if ((rc = mdb_sibling(cursor, move_right)) != MDB_SUCCESS)
2351 parent = CURSOR_TOP(cursor);
2357 DPRINTF("just moving to %s index key %u",
2358 move_right ? "right" : "left", parent->mp_ki);
2360 assert(IS_BRANCH(parent->mp_page));
2362 indx = NODEPTR(parent->mp_page, parent->mp_ki);
2363 if ((rc = mdb_get_page(cursor->mc_txn, NODEPGNO(indx), &mp)))
2366 mp->parent = parent->mp_page;
2367 mp->parent_index = parent->mp_ki;
2370 cursor_push_page(cursor, mp);
2376 mdb_cursor_next(MDB_cursor *cursor, MDB_val *key, MDB_val *data, MDB_cursor_op op)
2383 if (cursor->mc_flags & C_EOF) {
2384 return MDB_NOTFOUND;
2387 assert(cursor->mc_flags & C_INITIALIZED);
2389 top = CURSOR_TOP(cursor);
2392 if (cursor->mc_txn->mt_dbs[cursor->mc_dbi].md_flags & MDB_DUPSORT) {
2393 leaf = NODEPTR(mp, top->mp_ki);
2394 if (F_ISSET(leaf->mn_flags, F_DUPDATA)) {
2395 if (op == MDB_NEXT || op == MDB_NEXT_DUP) {
2396 rc = mdb_cursor_next(&cursor->mc_xcursor->mx_cursor, data, NULL, MDB_NEXT);
2397 if (op != MDB_NEXT || rc == MDB_SUCCESS)
2401 cursor->mc_xcursor->mx_cursor.mc_flags = 0;
2402 if (op == MDB_NEXT_DUP)
2403 return MDB_NOTFOUND;
2407 DPRINTF("cursor_next: top page is %lu in cursor %p", mp->mp_pgno, (void *) cursor);
2409 if (top->mp_ki + 1 >= NUMKEYS(mp)) {
2410 DPUTS("=====> move to next sibling page");
2411 if (mdb_sibling(cursor, 1) != MDB_SUCCESS) {
2412 cursor->mc_flags |= C_EOF;
2413 return MDB_NOTFOUND;
2415 top = CURSOR_TOP(cursor);
2417 DPRINTF("next page is %lu, key index %u", mp->mp_pgno, top->mp_ki);
2421 DPRINTF("==> cursor points to page %lu with %u keys, key index %u",
2422 mp->mp_pgno, NUMKEYS(mp), top->mp_ki);
2425 key->mv_size = cursor->mc_txn->mt_dbs[cursor->mc_dbi].md_pad;
2426 key->mv_data = LEAF2KEY(mp, top->mp_ki, key->mv_size);
2430 assert(IS_LEAF(mp));
2431 leaf = NODEPTR(mp, top->mp_ki);
2433 if (F_ISSET(leaf->mn_flags, F_DUPDATA)) {
2434 mdb_xcursor_init1(cursor, mp, leaf);
2437 if ((rc = mdb_read_data(cursor->mc_txn, leaf, data) != MDB_SUCCESS))
2440 if (F_ISSET(leaf->mn_flags, F_DUPDATA)) {
2441 rc = mdb_cursor_first(&cursor->mc_xcursor->mx_cursor, data, NULL);
2442 if (rc != MDB_SUCCESS)
2447 MDB_SET_KEY(leaf, key);
2452 mdb_cursor_prev(MDB_cursor *cursor, MDB_val *key, MDB_val *data, MDB_cursor_op op)
2459 assert(cursor->mc_flags & C_INITIALIZED);
2461 top = CURSOR_TOP(cursor);
2464 if (cursor->mc_txn->mt_dbs[cursor->mc_dbi].md_flags & MDB_DUPSORT) {
2465 leaf = NODEPTR(mp, top->mp_ki);
2466 if (op == MDB_PREV || op == MDB_PREV_DUP) {
2467 if (F_ISSET(leaf->mn_flags, F_DUPDATA)) {
2468 rc = mdb_cursor_prev(&cursor->mc_xcursor->mx_cursor, data, NULL, MDB_PREV);
2469 if (op != MDB_PREV || rc == MDB_SUCCESS)
2472 cursor->mc_xcursor->mx_cursor.mc_flags = 0;
2473 if (op == MDB_PREV_DUP)
2474 return MDB_NOTFOUND;
2479 DPRINTF("cursor_prev: top page is %lu in cursor %p", mp->mp_pgno, (void *) cursor);
2481 if (top->mp_ki == 0) {
2482 DPUTS("=====> move to prev sibling page");
2483 if (mdb_sibling(cursor, 0) != MDB_SUCCESS) {
2484 cursor->mc_flags &= ~C_INITIALIZED;
2485 return MDB_NOTFOUND;
2487 top = CURSOR_TOP(cursor);
2489 top->mp_ki = NUMKEYS(mp) - 1;
2490 DPRINTF("prev page is %lu, key index %u", mp->mp_pgno, top->mp_ki);
2494 cursor->mc_flags &= ~C_EOF;
2496 DPRINTF("==> cursor points to page %lu with %u keys, key index %u",
2497 mp->mp_pgno, NUMKEYS(mp), top->mp_ki);
2500 key->mv_size = cursor->mc_txn->mt_dbs[cursor->mc_dbi].md_pad;
2501 key->mv_data = LEAF2KEY(mp, top->mp_ki, key->mv_size);
2505 assert(IS_LEAF(mp));
2506 leaf = NODEPTR(mp, top->mp_ki);
2508 if (F_ISSET(leaf->mn_flags, F_DUPDATA)) {
2509 mdb_xcursor_init1(cursor, mp, leaf);
2512 if ((rc = mdb_read_data(cursor->mc_txn, leaf, data) != MDB_SUCCESS))
2515 if (F_ISSET(leaf->mn_flags, F_DUPDATA)) {
2516 rc = mdb_cursor_last(&cursor->mc_xcursor->mx_cursor, data, NULL);
2517 if (rc != MDB_SUCCESS)
2522 MDB_SET_KEY(leaf, key);
2527 mdb_cursor_set(MDB_cursor *cursor, MDB_val *key, MDB_val *data,
2528 MDB_cursor_op op, int *exactp)
2538 assert(key->mv_size > 0);
2540 /* See if we're already on the right page */
2541 if (cursor->mc_flags & C_INITIALIZED) {
2544 top = CURSOR_TOP(cursor);
2545 if (top->mp_page->mp_flags & P_LEAF2) {
2546 nodekey.mv_size = cursor->mc_txn->mt_dbs[cursor->mc_dbi].md_pad;
2547 nodekey.mv_data = LEAF2KEY(top->mp_page, 0, nodekey.mv_size);
2549 leaf = NODEPTR(top->mp_page, 0);
2550 MDB_SET_KEY(leaf, &nodekey);
2552 rc = cursor->mc_txn->mt_dbxs[cursor->mc_dbi].md_cmp(key, &nodekey);
2554 /* Probably happens rarely, but first node on the page
2555 * was the one we wanted.
2559 mpp.mp_page = top->mp_page;
2563 leaf = NODEPTR(top->mp_page, top->mp_ki);
2568 if (NUMKEYS(top->mp_page) > 1) {
2569 if (top->mp_page->mp_flags & P_LEAF2) {
2570 nodekey.mv_data = LEAF2KEY(top->mp_page,
2571 NUMKEYS(top->mp_page)-1, nodekey.mv_size);
2573 leaf = NODEPTR(top->mp_page, NUMKEYS(top->mp_page)-1);
2574 MDB_SET_KEY(leaf, &nodekey);
2576 rc = cursor->mc_txn->mt_dbxs[cursor->mc_dbi].md_cmp(key, &nodekey);
2578 /* last node was the one we wanted */
2579 top->mp_ki = NUMKEYS(top->mp_page)-1;
2583 /* This is definitely the right page, skip search_page */
2584 mpp.mp_page = top->mp_page;
2589 /* If any parents have right-sibs, search.
2590 * Otherwise, there's nothing further.
2592 for (i=0; i<cursor->mc_snum-1; i++)
2593 if (cursor->mc_stack[i].mp_ki <
2594 NUMKEYS(cursor->mc_stack[i].mp_page)-1)
2596 if (i == cursor->mc_snum - 1) {
2597 /* There are no other pages */
2598 top->mp_ki = NUMKEYS(top->mp_page);
2599 return MDB_NOTFOUND;
2604 cursor->mc_snum = 0;
2606 rc = mdb_search_page(cursor->mc_txn, cursor->mc_dbi, key, cursor, 0, &mpp);
2607 if (rc != MDB_SUCCESS)
2610 assert(IS_LEAF(mpp.mp_page));
2612 top = CURSOR_TOP(cursor);
2614 leaf = mdb_search_node(cursor->mc_txn, cursor->mc_dbi, mpp.mp_page, key, exactp, &top->mp_ki);
2615 if (exactp != NULL && !*exactp) {
2616 /* MDB_SET specified and not an exact match. */
2617 return MDB_NOTFOUND;
2621 DPUTS("===> inexact leaf not found, goto sibling");
2622 if ((rc = mdb_sibling(cursor, 1)) != MDB_SUCCESS)
2623 return rc; /* no entries matched */
2624 top = CURSOR_TOP(cursor);
2626 mpp.mp_page = top->mp_page;
2627 assert(IS_LEAF(mpp.mp_page));
2628 leaf = NODEPTR(mpp.mp_page, 0);
2632 cursor->mc_flags |= C_INITIALIZED;
2633 cursor->mc_flags &= ~C_EOF;
2635 if (IS_LEAF2(mpp.mp_page)) {
2636 key->mv_size = cursor->mc_txn->mt_dbs[cursor->mc_dbi].md_pad;
2637 key->mv_data = LEAF2KEY(mpp.mp_page, top->mp_ki, key->mv_size);
2641 if (F_ISSET(leaf->mn_flags, F_DUPDATA)) {
2642 mdb_xcursor_init1(cursor, mpp.mp_page, leaf);
2645 if (F_ISSET(leaf->mn_flags, F_DUPDATA)) {
2646 if (op == MDB_SET || op == MDB_SET_RANGE) {
2647 rc = mdb_cursor_first(&cursor->mc_xcursor->mx_cursor, data, NULL);
2650 if (op == MDB_GET_BOTH) {
2656 rc = mdb_cursor_set(&cursor->mc_xcursor->mx_cursor, data, NULL, MDB_SET_RANGE, ex2p);
2657 if (rc != MDB_SUCCESS)
2660 } else if (op == MDB_GET_BOTH || op == MDB_GET_BOTH_RANGE) {
2662 if ((rc = mdb_read_data(cursor->mc_txn, leaf, &d2)) != MDB_SUCCESS)
2664 rc = cursor->mc_txn->mt_dbxs[cursor->mc_dbi].md_cmp(data, &d2);
2666 if (op == MDB_GET_BOTH || rc > 0)
2667 return MDB_NOTFOUND;
2671 if ((rc = mdb_read_data(cursor->mc_txn, leaf, data)) != MDB_SUCCESS)
2676 /* The key already matches in all other cases */
2677 if (op == MDB_SET_RANGE)
2678 MDB_SET_KEY(leaf, key);
2679 DPRINTF("==> cursor placed on key [%s]", DKEY(key));
2685 mdb_cursor_first(MDB_cursor *cursor, MDB_val *key, MDB_val *data)
2691 cursor->mc_snum = 0;
2693 rc = mdb_search_page(cursor->mc_txn, cursor->mc_dbi, NULL, cursor, 0, &mpp);
2694 if (rc != MDB_SUCCESS)
2696 assert(IS_LEAF(mpp.mp_page));
2698 leaf = NODEPTR(mpp.mp_page, 0);
2699 cursor->mc_flags |= C_INITIALIZED;
2700 cursor->mc_flags &= ~C_EOF;
2702 if (IS_LEAF2(mpp.mp_page)) {
2703 key->mv_size = cursor->mc_txn->mt_dbs[cursor->mc_dbi].md_pad;
2704 key->mv_data = LEAF2KEY(mpp.mp_page, 0, key->mv_size);
2709 if (F_ISSET(leaf->mn_flags, F_DUPDATA)) {
2710 mdb_xcursor_init1(cursor, mpp.mp_page, leaf);
2711 rc = mdb_cursor_first(&cursor->mc_xcursor->mx_cursor, data, NULL);
2715 if (cursor->mc_xcursor)
2716 cursor->mc_xcursor->mx_cursor.mc_flags = 0;
2717 if ((rc = mdb_read_data(cursor->mc_txn, leaf, data)) != MDB_SUCCESS)
2721 MDB_SET_KEY(leaf, key);
2726 mdb_cursor_last(MDB_cursor *cursor, MDB_val *key, MDB_val *data)
2734 cursor->mc_snum = 0;
2736 lkey.mv_size = MAXKEYSIZE+1;
2737 lkey.mv_data = NULL;
2739 rc = mdb_search_page(cursor->mc_txn, cursor->mc_dbi, &lkey, cursor, 0, &mpp);
2740 if (rc != MDB_SUCCESS)
2742 assert(IS_LEAF(mpp.mp_page));
2744 leaf = NODEPTR(mpp.mp_page, NUMKEYS(mpp.mp_page)-1);
2745 cursor->mc_flags |= C_INITIALIZED;
2746 cursor->mc_flags &= ~C_EOF;
2748 top = CURSOR_TOP(cursor);
2749 top->mp_ki = NUMKEYS(top->mp_page) - 1;
2751 if (IS_LEAF2(mpp.mp_page)) {
2752 key->mv_size = cursor->mc_txn->mt_dbs[cursor->mc_dbi].md_pad;
2753 key->mv_data = LEAF2KEY(mpp.mp_page, top->mp_ki, key->mv_size);
2758 if (F_ISSET(leaf->mn_flags, F_DUPDATA)) {
2759 mdb_xcursor_init1(cursor, mpp.mp_page, leaf);
2760 rc = mdb_cursor_last(&cursor->mc_xcursor->mx_cursor, data, NULL);
2764 if ((rc = mdb_read_data(cursor->mc_txn, leaf, data)) != MDB_SUCCESS)
2769 MDB_SET_KEY(leaf, key);
2774 mdb_cursor_get(MDB_cursor *cursor, MDB_val *key, MDB_val *data,
2784 case MDB_GET_BOTH_RANGE:
2785 if (data == NULL || cursor->mc_xcursor == NULL) {
2792 if (key == NULL || key->mv_size == 0 || key->mv_size > MAXKEYSIZE) {
2794 } else if (op == MDB_SET_RANGE)
2795 rc = mdb_cursor_set(cursor, key, data, op, NULL);
2797 rc = mdb_cursor_set(cursor, key, data, op, &exact);
2799 case MDB_GET_MULTIPLE:
2801 !(cursor->mc_txn->mt_dbs[cursor->mc_dbi].md_flags & MDB_DUPFIXED) ||
2802 !(cursor->mc_flags & C_INITIALIZED)) {
2807 if (!(cursor->mc_xcursor->mx_cursor.mc_flags & C_INITIALIZED) ||
2808 (cursor->mc_xcursor->mx_cursor.mc_flags & C_EOF))
2811 case MDB_NEXT_MULTIPLE:
2813 !(cursor->mc_txn->mt_dbs[cursor->mc_dbi].md_flags & MDB_DUPFIXED)) {
2817 if (!(cursor->mc_flags & C_INITIALIZED))
2818 rc = mdb_cursor_first(cursor, key, data);
2820 rc = mdb_cursor_next(cursor, key, data, MDB_NEXT_DUP);
2821 if (rc == MDB_SUCCESS) {
2822 if (cursor->mc_xcursor->mx_cursor.mc_flags & C_INITIALIZED) {
2825 top = CURSOR_TOP(&cursor->mc_xcursor->mx_cursor);
2826 data->mv_size = NUMKEYS(top->mp_page) *
2827 cursor->mc_xcursor->mx_txn.mt_dbs[cursor->mc_xcursor->mx_cursor.mc_dbi].md_pad;
2828 data->mv_data = METADATA(top->mp_page);
2829 top->mp_ki = NUMKEYS(top->mp_page)-1;
2837 case MDB_NEXT_NODUP:
2838 if (!(cursor->mc_flags & C_INITIALIZED))
2839 rc = mdb_cursor_first(cursor, key, data);
2841 rc = mdb_cursor_next(cursor, key, data, op);
2845 case MDB_PREV_NODUP:
2846 if (!(cursor->mc_flags & C_INITIALIZED) || (cursor->mc_flags & C_EOF))
2847 rc = mdb_cursor_last(cursor, key, data);
2849 rc = mdb_cursor_prev(cursor, key, data, op);
2852 rc = mdb_cursor_first(cursor, key, data);
2856 !(cursor->mc_txn->mt_dbs[cursor->mc_dbi].md_flags & MDB_DUPSORT) ||
2857 !(cursor->mc_flags & C_INITIALIZED) ||
2858 !(cursor->mc_xcursor->mx_cursor.mc_flags & C_INITIALIZED)) {
2862 rc = mdb_cursor_first(&cursor->mc_xcursor->mx_cursor, data, NULL);
2865 rc = mdb_cursor_last(cursor, key, data);
2869 !(cursor->mc_txn->mt_dbs[cursor->mc_dbi].md_flags & MDB_DUPSORT) ||
2870 !(cursor->mc_flags & C_INITIALIZED) ||
2871 !(cursor->mc_xcursor->mx_cursor.mc_flags & C_INITIALIZED)) {
2875 rc = mdb_cursor_last(&cursor->mc_xcursor->mx_cursor, data, NULL);
2878 DPRINTF("unhandled/unimplemented cursor operation %u", op);
2887 mdb_cursor_touch(MDB_cursor *mc)
2894 mpp.mp_parent = NULL;
2896 if (mc->mc_dbi > MAIN_DBI && !mc->mc_txn->mt_dbxs[mc->mc_dbi].md_dirty) {
2897 rc = mdb_search_page(mc->mc_txn, MAIN_DBI, &mc->mc_txn->mt_dbxs[mc->mc_dbi].md_name,
2900 mc->mc_txn->mt_dbxs[mc->mc_dbi].md_dirty = 1;
2902 for(i=0; i<mc->mc_snum; i++) {
2903 mpp.mp_page = mc->mc_stack[i].mp_page;
2904 if (!F_ISSET(mpp.mp_page->mp_flags, P_DIRTY)) {
2905 rc = mdb_touch(mc->mc_txn, mc->mc_dbi, &mpp);
2907 mc->mc_stack[i].mp_page = mpp.mp_page;
2909 mc->mc_txn->mt_dbs[mc->mc_dbi].md_root = mpp.mp_page->mp_pgno;
2912 dh = ((MDB_dhead *)mpp.mp_page)-1;
2913 dh->md_parent = mpp.mp_parent;
2914 dh->md_pi = mpp.mp_pi;
2915 mpp.mp_parent = mpp.mp_page;
2916 mpp.mp_pi = mc->mc_stack[i].mp_ki;
2922 mdb_cursor_put(MDB_cursor *mc, MDB_val *key, MDB_val *data,
2927 MDB_val xdata, *rdata, dkey;
2929 char dbuf[PAGESIZE];
2935 if (F_ISSET(mc->mc_txn->mt_flags, MDB_TXN_RDONLY))
2938 DPRINTF("==> put db %u key [%s], size %zu, data size %zu",
2939 mc->mc_dbi, DKEY(key), key->mv_size, data->mv_size);
2943 if (flags == MDB_CURRENT) {
2944 if (!(mc->mc_flags & C_INITIALIZED))
2947 } else if (mc->mc_txn->mt_dbs[mc->mc_dbi].md_root == P_INVALID) {
2949 /* new database, write a root leaf page */
2950 DPUTS("allocating new root leaf page");
2951 if ((dp = mdb_new_page(mc->mc_txn, mc->mc_dbi, P_LEAF, 1)) == NULL) {
2955 cursor_push_page(mc, &dp->p);
2956 mc->mc_txn->mt_dbs[mc->mc_dbi].md_root = dp->p.mp_pgno;
2957 mc->mc_txn->mt_dbs[mc->mc_dbi].md_depth++;
2958 mc->mc_txn->mt_dbxs[mc->mc_dbi].md_dirty = 1;
2959 if ((mc->mc_txn->mt_dbs[mc->mc_dbi].md_flags & (MDB_DUPSORT|MDB_DUPFIXED))
2961 dp->p.mp_flags |= P_LEAF2;
2962 mc->mc_flags |= C_INITIALIZED;
2967 rc = mdb_cursor_set(mc, key, NULL, MDB_SET, &exact);
2968 if (flags == MDB_NOOVERWRITE && rc == 0) {
2969 DPRINTF("duplicate key [%s]", DKEY(key));
2970 return MDB_KEYEXIST;
2972 if (rc && rc != MDB_NOTFOUND)
2976 /* Cursor is positioned, now make sure all pages are writable */
2977 rc2 = mdb_cursor_touch(mc);
2978 if (rc2) return rc2;
2981 top = CURSOR_TOP(mc);
2983 /* The key already exists */
2984 if (rc == MDB_SUCCESS) {
2985 /* there's only a key anyway, so this is a no-op */
2986 if (IS_LEAF2(top->mp_page)) {
2987 unsigned int ksize = mc->mc_txn->mt_dbs[mc->mc_dbi].md_pad;
2988 if (key->mv_size != ksize)
2990 if (flags == MDB_CURRENT) {
2991 char *ptr = LEAF2KEY(top->mp_page, top->mp_ki, ksize);
2992 memcpy(ptr, key->mv_data, ksize);
2997 leaf = NODEPTR(top->mp_page, top->mp_ki);
3000 if (F_ISSET(mc->mc_txn->mt_dbs[mc->mc_dbi].md_flags, MDB_DUPSORT)) {
3001 /* Was a single item before, must convert now */
3002 if (!F_ISSET(leaf->mn_flags, F_DUPDATA)) {
3003 dkey.mv_size = NODEDSZ(leaf);
3004 dkey.mv_data = dbuf;
3005 memcpy(dbuf, NODEDATA(leaf), dkey.mv_size);
3006 /* data matches, ignore it */
3007 if (!mdb_dcmp(mc->mc_txn, mc->mc_dbi, data, &dkey))
3008 return (flags == MDB_NODUPDATA) ? MDB_KEYEXIST : MDB_SUCCESS;
3009 memset(&dummy, 0, sizeof(dummy));
3010 if (mc->mc_txn->mt_dbs[mc->mc_dbi].md_flags & MDB_DUPFIXED) {
3011 dummy.md_pad = data->mv_size;
3012 dummy.md_flags = MDB_DUPFIXED;
3013 if (mc->mc_txn->mt_dbs[mc->mc_dbi].md_flags & MDB_INTEGERDUP)
3014 dummy.md_flags |= MDB_INTEGERKEY;
3016 dummy.md_root = P_INVALID;
3017 if (dkey.mv_size == sizeof(MDB_db)) {
3018 memcpy(NODEDATA(leaf), &dummy, sizeof(dummy));
3021 mdb_del_node(top->mp_page, top->mp_ki, 0);
3024 xdata.mv_size = sizeof(MDB_db);
3025 xdata.mv_data = &dummy;
3030 /* same size, just replace it */
3031 if (!F_ISSET(leaf->mn_flags, F_BIGDATA) &&
3032 NODEDSZ(leaf) == data->mv_size) {
3033 memcpy(NODEDATA(leaf), data->mv_data, data->mv_size);
3036 mdb_del_node(top->mp_page, top->mp_ki, 0);
3038 DPRINTF("inserting key at index %i", top->mp_ki);
3044 nsize = IS_LEAF2(top->mp_page) ? key->mv_size : mdb_leaf_size(mc->mc_txn->mt_env, key, rdata);
3045 if (SIZELEFT(top->mp_page) < nsize) {
3046 rc = mdb_split(mc->mc_txn, mc->mc_dbi, &top->mp_page, &top->mp_ki, key, rdata, P_INVALID);
3048 /* There is room already in this leaf page. */
3049 rc = mdb_add_node(mc->mc_txn, mc->mc_dbi, top->mp_page, top->mp_ki, key, rdata, 0, 0);
3052 if (rc != MDB_SUCCESS)
3053 mc->mc_txn->mt_flags |= MDB_TXN_ERROR;
3055 /* Remember if we just added a subdatabase */
3056 if (flags & F_SUBDATA) {
3057 leaf = NODEPTR(top->mp_page, top->mp_ki);
3058 leaf->mn_flags |= F_SUBDATA;
3061 /* Now store the actual data in the child DB. Note that we're
3062 * storing the user data in the keys field, so there are strict
3063 * size limits on dupdata. The actual data fields of the child
3064 * DB are all zero size.
3067 leaf = NODEPTR(top->mp_page, top->mp_ki);
3069 if (flags == MDB_CURRENT)
3070 mdb_xcursor_init2(mc);
3072 mdb_xcursor_init1(mc, top->mp_page, leaf);
3075 if (flags == MDB_NODUPDATA)
3076 flags = MDB_NOOVERWRITE;
3077 /* converted, write the original data first */
3079 rc = mdb_cursor_put(&mc->mc_xcursor->mx_cursor, &dkey, &xdata, flags);
3081 leaf->mn_flags |= F_DUPDATA;
3083 rc = mdb_cursor_put(&mc->mc_xcursor->mx_cursor, data, &xdata, flags);
3084 mdb_xcursor_fini(mc);
3085 memcpy(NODEDATA(leaf),
3086 &mc->mc_xcursor->mx_txn.mt_dbs[mc->mc_xcursor->mx_cursor.mc_dbi],
3089 mc->mc_txn->mt_dbs[mc->mc_dbi].md_entries++;
3096 mdb_cursor_del(MDB_cursor *mc, unsigned int flags)
3103 if (F_ISSET(mc->mc_txn->mt_flags, MDB_TXN_RDONLY))
3106 if (!mc->mc_flags & C_INITIALIZED)
3109 rc = mdb_cursor_touch(mc);
3112 top = CURSOR_TOP(mc);
3113 leaf = NODEPTR(top->mp_page, top->mp_ki);
3114 mpp.mp_page = top->mp_page;
3115 if (mc->mc_snum > 1) {
3116 MDB_ppage *parent = CURSOR_PARENT(mc);
3117 mpp.mp_parent = parent->mp_page;
3118 mpp.mp_pi = parent->mp_ki;
3120 mpp.mp_parent = NULL;
3124 if (!IS_LEAF2(top->mp_page) && F_ISSET(leaf->mn_flags, F_DUPDATA)) {
3127 if (flags != MDB_NODUPDATA) {
3128 /* mdb_xcursor_init2(mc); */
3129 rc = mdb_cursor_del(&mc->mc_xcursor->mx_cursor, 0);
3130 mdb_xcursor_fini(mc);
3131 /* If sub-DB still has entries, we're done */
3132 if (mc->mc_xcursor->mx_txn.mt_dbs[mc->mc_xcursor->mx_cursor.mc_dbi].md_root
3134 memcpy(NODEDATA(leaf),
3135 &mc->mc_xcursor->mx_txn.mt_dbs[mc->mc_xcursor->mx_cursor.mc_dbi],
3137 mc->mc_txn->mt_dbs[mc->mc_dbi].md_entries--;
3140 /* otherwise fall thru and delete the sub-DB */
3143 /* add all the child DB's pages to the free list */
3144 mc->mc_xcursor->mx_cursor.mc_snum = 0;
3145 rc = mdb_search_page(&mc->mc_xcursor->mx_txn, mc->mc_xcursor->mx_cursor.mc_dbi,
3146 NULL, &mc->mc_xcursor->mx_cursor, 0, &mp2);
3147 if (rc == MDB_SUCCESS) {
3148 MDB_ppage *top, *parent;
3157 mc->mc_txn->mt_dbs[mc->mc_dbi].md_entries -=
3158 mc->mc_xcursor->mx_txn.mt_dbs[mc->mc_xcursor->mx_cursor.mc_dbi].md_entries;
3160 cursor_pop_page(&mc->mc_xcursor->mx_cursor);
3161 if (mc->mc_xcursor->mx_cursor.mc_snum) {
3163 if (mc->mc_xcursor->mx_cursor.mc_stack[0].mp_page->mp_flags & P_DIRTY) {
3167 while (mc->mc_xcursor->mx_cursor.mc_snum > 1) {
3168 top = CURSOR_TOP(&mc->mc_xcursor->mx_cursor);
3169 parent = CURSOR_PARENT(&mc->mc_xcursor->mx_cursor);
3170 for (i=0; i<NUMKEYS(top->mp_page); i++) {
3173 ni = NODEPTR(top->mp_page, i);
3175 if ((rc = mdb_get_page(mc->mc_txn, pg, &mp)))
3178 if (mp->mp_flags & P_DIRTY) {
3181 mdb_mid2l_delete(mc->mc_txn->mt_u.dirty_list, &mid);
3183 dp->h.md_parent = (MDB_page *)mc->mc_txn->mt_env->me_dpages;
3184 mc->mc_txn->mt_env->me_dpages = dp;
3189 mdb_midl_append(mc->mc_txn->mt_free_pgs, pg);
3192 rc = mdb_sibling(&mc->mc_xcursor->mx_cursor, 1);
3199 mid.mid = mc->mc_xcursor->mx_txn.mt_dbs[mc->mc_xcursor->mx_cursor.mc_dbi].md_root;
3200 mdb_mid2l_delete(mc->mc_txn->mt_u.dirty_list, &mid);
3202 dp->h.md_parent = (MDB_page *)mc->mc_txn->mt_env->me_dpages;
3203 mc->mc_txn->mt_env->me_dpages = dp;
3208 mdb_midl_append(mc->mc_txn->mt_free_pgs,
3209 mc->mc_xcursor->mx_txn.mt_dbs[mc->mc_xcursor->mx_cursor.mc_dbi].md_root);
3214 return mdb_del0(mc, top->mp_ki, &mpp, leaf);
3217 /* Allocate a page and initialize it
3220 mdb_new_page(MDB_txn *txn, MDB_dbi dbi, uint32_t flags, int num)
3224 if ((dp = mdb_alloc_page(txn, dbi, NULL, 0, num)) == NULL)
3226 DPRINTF("allocated new mpage %lu, page size %u",
3227 dp->p.mp_pgno, txn->mt_env->me_psize);
3228 dp->p.mp_flags = flags | P_DIRTY;
3229 dp->p.mp_lower = PAGEHDRSZ;
3230 dp->p.mp_upper = txn->mt_env->me_psize;
3232 if (IS_BRANCH(&dp->p))
3233 txn->mt_dbs[dbi].md_branch_pages++;
3234 else if (IS_LEAF(&dp->p))
3235 txn->mt_dbs[dbi].md_leaf_pages++;
3236 else if (IS_OVERFLOW(&dp->p)) {
3237 txn->mt_dbs[dbi].md_overflow_pages += num;
3238 dp->p.mp_pages = num;
3245 mdb_leaf_size(MDB_env *env, MDB_val *key, MDB_val *data)
3249 sz = LEAFSIZE(key, data);
3250 if (data->mv_size >= env->me_psize / MDB_MINKEYS) {
3251 /* put on overflow page */
3252 sz -= data->mv_size - sizeof(pgno_t);
3255 return sz + sizeof(indx_t);
3259 mdb_branch_size(MDB_env *env, MDB_val *key)
3264 if (sz >= env->me_psize / MDB_MINKEYS) {
3265 /* put on overflow page */
3266 /* not implemented */
3267 /* sz -= key->size - sizeof(pgno_t); */
3270 return sz + sizeof(indx_t);
3274 mdb_add_node(MDB_txn *txn, MDB_dbi dbi, MDB_page *mp, indx_t indx,
3275 MDB_val *key, MDB_val *data, pgno_t pgno, uint8_t flags)
3278 size_t node_size = NODESIZE;
3281 MDB_dpage *ofp = NULL; /* overflow page */
3284 assert(mp->mp_upper >= mp->mp_lower);
3286 DPRINTF("add to %s page %lu index %i, data size %zu key size %zu [%s]",
3287 IS_LEAF(mp) ? "leaf" : "branch",
3288 mp->mp_pgno, indx, data ? data->mv_size : 0,
3289 key ? key->mv_size : 0, key ? DKEY(key) : NULL);
3292 /* Move higher keys up one slot. */
3293 int ksize = txn->mt_dbs[dbi].md_pad, dif;
3294 char *ptr = LEAF2KEY(mp, indx, ksize);
3295 dif = NUMKEYS(mp) - indx;
3297 memmove(ptr+ksize, ptr, dif*ksize);
3298 /* insert new key */
3299 memcpy(ptr, key->mv_data, ksize);
3301 /* Just using these for counting */
3302 mp->mp_lower += sizeof(indx_t);
3303 mp->mp_upper -= ksize - sizeof(indx_t);
3308 node_size += key->mv_size;
3312 if (F_ISSET(flags, F_BIGDATA)) {
3313 /* Data already on overflow page. */
3314 node_size += sizeof(pgno_t);
3315 } else if (data->mv_size >= txn->mt_env->me_psize / MDB_MINKEYS) {
3316 int ovpages = OVPAGES(data->mv_size, txn->mt_env->me_psize);
3317 /* Put data on overflow page. */
3318 DPRINTF("data size is %zu, put on overflow page",
3320 node_size += sizeof(pgno_t);
3321 if ((ofp = mdb_new_page(txn, dbi, P_OVERFLOW, ovpages)) == NULL)
3323 DPRINTF("allocated overflow page %lu", ofp->p.mp_pgno);
3326 node_size += data->mv_size;
3330 if (node_size + sizeof(indx_t) > SIZELEFT(mp)) {
3331 DPRINTF("not enough room in page %lu, got %u ptrs",
3332 mp->mp_pgno, NUMKEYS(mp));
3333 DPRINTF("upper - lower = %u - %u = %u", mp->mp_upper, mp->mp_lower,
3334 mp->mp_upper - mp->mp_lower);
3335 DPRINTF("node size = %zu", node_size);
3339 /* Move higher pointers up one slot. */
3340 for (i = NUMKEYS(mp); i > indx; i--)
3341 mp->mp_ptrs[i] = mp->mp_ptrs[i - 1];
3343 /* Adjust free space offsets. */
3344 ofs = mp->mp_upper - node_size;
3345 assert(ofs >= mp->mp_lower + sizeof(indx_t));
3346 mp->mp_ptrs[indx] = ofs;
3348 mp->mp_lower += sizeof(indx_t);
3350 /* Write the node data. */
3351 node = NODEPTR(mp, indx);
3352 node->mn_ksize = (key == NULL) ? 0 : key->mv_size;
3353 node->mn_flags = flags;
3355 SETDSZ(node,data->mv_size);
3360 memcpy(NODEKEY(node), key->mv_data, key->mv_size);
3365 if (F_ISSET(flags, F_BIGDATA))
3366 memcpy(node->mn_data + key->mv_size, data->mv_data,
3369 memcpy(node->mn_data + key->mv_size, data->mv_data,
3372 memcpy(node->mn_data + key->mv_size, &ofp->p.mp_pgno,
3374 memcpy(METADATA(&ofp->p), data->mv_data, data->mv_size);
3382 mdb_del_node(MDB_page *mp, indx_t indx, int ksize)
3385 indx_t i, j, numkeys, ptr;
3389 DPRINTF("delete node %u on %s page %lu", indx,
3390 IS_LEAF(mp) ? "leaf" : "branch", mp->mp_pgno);
3391 assert(indx < NUMKEYS(mp));
3394 int x = NUMKEYS(mp) - 1 - indx;
3395 base = LEAF2KEY(mp, indx, ksize);
3397 memmove(base, base + ksize, x * ksize);
3398 mp->mp_lower -= sizeof(indx_t);
3399 mp->mp_upper += ksize - sizeof(indx_t);
3403 node = NODEPTR(mp, indx);
3404 sz = NODESIZE + node->mn_ksize;
3406 if (F_ISSET(node->mn_flags, F_BIGDATA))
3407 sz += sizeof(pgno_t);
3409 sz += NODEDSZ(node);
3412 ptr = mp->mp_ptrs[indx];
3413 numkeys = NUMKEYS(mp);
3414 for (i = j = 0; i < numkeys; i++) {
3416 mp->mp_ptrs[j] = mp->mp_ptrs[i];
3417 if (mp->mp_ptrs[i] < ptr)
3418 mp->mp_ptrs[j] += sz;
3423 base = (char *)mp + mp->mp_upper;
3424 memmove(base + sz, base, ptr - mp->mp_upper);
3426 mp->mp_lower -= sizeof(indx_t);
3431 mdb_xcursor_init0(MDB_cursor *mc)
3433 MDB_xcursor *mx = mc->mc_xcursor;
3436 mx->mx_txn = *mc->mc_txn;
3437 mx->mx_txn.mt_dbxs = mx->mx_dbxs;
3438 mx->mx_txn.mt_dbs = mx->mx_dbs;
3439 mx->mx_dbxs[0] = mc->mc_txn->mt_dbxs[0];
3440 mx->mx_dbxs[1] = mc->mc_txn->mt_dbxs[1];
3441 if (mc->mc_dbi > 1) {
3442 mx->mx_dbxs[2] = mc->mc_txn->mt_dbxs[mc->mc_dbi];
3447 mx->mx_dbxs[dbn+1].md_parent = dbn;
3448 mx->mx_dbxs[dbn+1].md_cmp = mx->mx_dbxs[dbn].md_dcmp;
3449 mx->mx_dbxs[dbn+1].md_rel = mx->mx_dbxs[dbn].md_rel;
3450 mx->mx_dbxs[dbn+1].md_dirty = 0;
3451 mx->mx_txn.mt_numdbs = dbn+2;
3453 mx->mx_cursor.mc_xcursor = NULL;
3454 mx->mx_cursor.mc_txn = &mx->mx_txn;
3455 mx->mx_cursor.mc_dbi = dbn+1;
3459 mdb_xcursor_init1(MDB_cursor *mc, MDB_page *mp, MDB_node *node)
3461 MDB_db *db = NODEDATA(node);
3462 MDB_xcursor *mx = mc->mc_xcursor;
3464 mx->mx_dbs[0] = mc->mc_txn->mt_dbs[0];
3465 mx->mx_dbs[1] = mc->mc_txn->mt_dbs[1];
3466 if (mc->mc_dbi > 1) {
3467 mx->mx_dbs[2] = mc->mc_txn->mt_dbs[mc->mc_dbi];
3472 DPRINTF("Sub-db %u for db %u root page %lu", dbn, mc->mc_dbi, db->md_root);
3473 mx->mx_dbs[dbn] = *db;
3474 if (F_ISSET(mp->mp_flags, P_DIRTY))
3475 mx->mx_dbxs[dbn].md_dirty = 1;
3476 mx->mx_dbxs[dbn].md_name.mv_data = NODEKEY(node);
3477 mx->mx_dbxs[dbn].md_name.mv_size = node->mn_ksize;
3478 mx->mx_txn.mt_next_pgno = mc->mc_txn->mt_next_pgno;
3479 mx->mx_txn.mt_u = mc->mc_txn->mt_u;
3480 mx->mx_cursor.mc_snum = 0;
3481 mx->mx_cursor.mc_flags = 0;
3485 mdb_xcursor_init2(MDB_cursor *mc)
3487 MDB_xcursor *mx = mc->mc_xcursor;
3489 mx->mx_dbs[0] = mc->mc_txn->mt_dbs[0];
3490 mx->mx_dbs[1] = mc->mc_txn->mt_dbs[1];
3491 if (mc->mc_dbi > 1) {
3492 mx->mx_dbs[2] = mc->mc_txn->mt_dbs[mc->mc_dbi];
3497 DPRINTF("Sub-db %u for db %u root page %lu", dbn, mc->mc_dbi,
3498 mx->mx_dbs[dbn].md_root);
3499 mx->mx_txn.mt_next_pgno = mc->mc_txn->mt_next_pgno;
3503 mdb_xcursor_fini(MDB_cursor *mc)
3505 MDB_xcursor *mx = mc->mc_xcursor;
3506 mc->mc_txn->mt_next_pgno = mx->mx_txn.mt_next_pgno;
3507 mc->mc_txn->mt_dbs[0] = mx->mx_dbs[0];
3508 mc->mc_txn->mt_dbs[1] = mx->mx_dbs[1];
3509 mc->mc_txn->mt_dbxs[0].md_dirty = mx->mx_dbxs[0].md_dirty;
3510 mc->mc_txn->mt_dbxs[1].md_dirty = mx->mx_dbxs[1].md_dirty;
3511 if (mc->mc_dbi > 1) {
3512 mc->mc_txn->mt_dbs[mc->mc_dbi] = mx->mx_dbs[2];
3513 mc->mc_txn->mt_dbxs[mc->mc_dbi].md_dirty = mx->mx_dbxs[2].md_dirty;
3518 mdb_cursor_open(MDB_txn *txn, MDB_dbi dbi, MDB_cursor **ret)
3521 size_t size = sizeof(MDB_cursor);
3523 if (txn == NULL || ret == NULL || !dbi || dbi >= txn->mt_numdbs)
3526 if (txn->mt_dbs[dbi].md_flags & MDB_DUPSORT)
3527 size += sizeof(MDB_xcursor);
3529 if ((cursor = calloc(1, size)) != NULL) {
3530 cursor->mc_dbi = dbi;
3531 cursor->mc_txn = txn;
3532 if (txn->mt_dbs[dbi].md_flags & MDB_DUPSORT) {
3533 MDB_xcursor *mx = (MDB_xcursor *)(cursor + 1);
3534 cursor->mc_xcursor = mx;
3535 mdb_xcursor_init0(cursor);
3546 /* Return the count of duplicate data items for the current key */
3548 mdb_cursor_count(MDB_cursor *mc, unsigned long *countp)
3553 if (mc == NULL || countp == NULL)
3556 if (!(mc->mc_txn->mt_dbs[mc->mc_dbi].md_flags & MDB_DUPSORT))
3559 top = CURSOR_TOP(mc);
3560 leaf = NODEPTR(top->mp_page, top->mp_ki);
3561 if (!F_ISSET(leaf->mn_flags, F_DUPDATA)) {
3564 if (!(mc->mc_xcursor->mx_cursor.mc_flags & C_INITIALIZED))
3567 *countp = mc->mc_xcursor->mx_txn.mt_dbs[mc->mc_xcursor->mx_cursor.mc_dbi].md_entries;
3574 mdb_cursor_reset(MDB_cursor *mc)
3577 if (mc->mc_flags & C_XDIRTY) {
3579 mdb_xcursor_fini(mc);
3581 /* If sub-DB still has entries, update root record */
3582 if (mc->mc_xcursor->mx_txn.mt_dbs[mc->mc_xcursor->mx_cursor.mc_dbi].md_root
3586 top = CURSOR_TOP(mc);
3587 leaf = NODEPTR(top->mp_page, top->mp_ki);
3588 memcpy(NODEDATA(leaf),
3589 &mc->mc_xcursor->mx_txn.mt_dbs[mc->mc_xcursor->mx_cursor.mc_dbi],
3592 mc->mc_flags ^= C_XDIRTY;
3599 mdb_cursor_close(MDB_cursor *cursor)
3601 if (cursor != NULL) {
3607 mdb_update_key(MDB_page *mp, indx_t indx, MDB_val *key)
3609 indx_t ptr, i, numkeys;
3616 node = NODEPTR(mp, indx);
3617 ptr = mp->mp_ptrs[indx];
3618 DPRINTF("update key %u (ofs %u) [%.*s] to [%s] on page %lu",
3620 (int)node->mn_ksize, (char *)NODEKEY(node),
3624 delta = key->mv_size - node->mn_ksize;
3626 if (delta > 0 && SIZELEFT(mp) < delta) {
3627 DPRINTF("OUCH! Not enough room, delta = %d", delta);
3631 numkeys = NUMKEYS(mp);
3632 for (i = 0; i < numkeys; i++) {
3633 if (mp->mp_ptrs[i] <= ptr)
3634 mp->mp_ptrs[i] -= delta;
3637 base = (char *)mp + mp->mp_upper;
3638 len = ptr - mp->mp_upper + NODESIZE;
3639 memmove(base - delta, base, len);
3640 mp->mp_upper -= delta;
3642 node = NODEPTR(mp, indx);
3643 node->mn_ksize = key->mv_size;
3646 memcpy(NODEKEY(node), key->mv_data, key->mv_size);
3651 /* Move a node from src to dst.
3654 mdb_move_node(MDB_txn *txn, MDB_dbi dbi, MDB_pageparent *src, indx_t srcindx,
3655 MDB_pageparent *dst, indx_t dstindx)
3662 /* Mark src and dst as dirty. */
3663 if ((rc = mdb_touch(txn, dbi, src)) ||
3664 (rc = mdb_touch(txn, dbi, dst)))
3667 if (IS_LEAF2(src->mp_page)) {
3668 srcnode = NODEPTR(src->mp_page, 0); /* fake */
3669 key.mv_size = txn->mt_dbs[dbi].md_pad;
3670 key.mv_data = LEAF2KEY(src->mp_page, srcindx, key.mv_size);
3672 data.mv_data = NULL;
3674 srcnode = NODEPTR(src->mp_page, srcindx);
3675 key.mv_size = NODEKSZ(srcnode);
3676 key.mv_data = NODEKEY(srcnode);
3677 data.mv_size = NODEDSZ(srcnode);
3678 data.mv_data = NODEDATA(srcnode);
3680 DPRINTF("moving %s node %u [%s] on page %lu to node %u on page %lu",
3681 IS_LEAF(src->mp_page) ? "leaf" : "branch",
3684 src->mp_page->mp_pgno,
3685 dstindx, dst->mp_page->mp_pgno);
3687 /* Add the node to the destination page.
3689 rc = mdb_add_node(txn, dbi, dst->mp_page, dstindx, &key, &data, NODEPGNO(srcnode),
3691 if (rc != MDB_SUCCESS)
3694 /* Delete the node from the source page.
3696 mdb_del_node(src->mp_page, srcindx, key.mv_size);
3698 /* The key value just changed due to del_node, find it again.
3700 if (!IS_LEAF2(src->mp_page)) {
3701 srcnode = NODEPTR(src->mp_page, srcindx);
3702 key.mv_data = NODEKEY(srcnode);
3705 /* Update the parent separators.
3708 if (src->mp_pi != 0) {
3709 DPRINTF("update separator for source page %lu to [%s]",
3710 src->mp_page->mp_pgno, DKEY(&key));
3711 if ((rc = mdb_update_key(src->mp_parent, src->mp_pi,
3712 &key)) != MDB_SUCCESS)
3715 if (IS_BRANCH(src->mp_page)) {
3717 nullkey.mv_size = 0;
3718 assert(mdb_update_key(src->mp_page, 0, &nullkey) == MDB_SUCCESS);
3723 if (dst->mp_pi != 0) {
3724 DPRINTF("update separator for destination page %lu to [%s]",
3725 dst->mp_page->mp_pgno, DKEY(&key));
3726 if ((rc = mdb_update_key(dst->mp_parent, dst->mp_pi,
3727 &key)) != MDB_SUCCESS)
3730 if (IS_BRANCH(dst->mp_page)) {
3732 nullkey.mv_size = 0;
3733 assert(mdb_update_key(dst->mp_page, 0, &nullkey) == MDB_SUCCESS);
3741 mdb_merge(MDB_txn *txn, MDB_dbi dbi, MDB_pageparent *src, MDB_pageparent *dst)
3750 DPRINTF("merging page %lu and %lu", src->mp_page->mp_pgno, dst->mp_page->mp_pgno);
3752 assert(txn != NULL);
3753 assert(src->mp_parent); /* can't merge root page */
3754 assert(dst->mp_parent);
3756 /* Mark src and dst as dirty. */
3757 if ((rc = mdb_touch(txn, dbi, src)) ||
3758 (rc = mdb_touch(txn, dbi, dst)))
3761 /* Move all nodes from src to dst.
3763 if (IS_LEAF2(src->mp_page)) {
3764 key.mv_size = txn->mt_dbs[dbi].md_pad;
3765 key.mv_data = METADATA(src->mp_page);
3766 for (i = 0; i < NUMKEYS(src->mp_page); i++) {
3767 rc = mdb_add_node(txn, dbi, dst->mp_page, NUMKEYS(dst->mp_page), &key,
3769 if (rc != MDB_SUCCESS)
3771 key.mv_data = (char *)key.mv_data + key.mv_size;
3774 for (i = 0; i < NUMKEYS(src->mp_page); i++) {
3775 srcnode = NODEPTR(src->mp_page, i);
3777 key.mv_size = srcnode->mn_ksize;
3778 key.mv_data = NODEKEY(srcnode);
3779 data.mv_size = NODEDSZ(srcnode);
3780 data.mv_data = NODEDATA(srcnode);
3781 rc = mdb_add_node(txn, dbi, dst->mp_page, NUMKEYS(dst->mp_page), &key,
3782 &data, NODEPGNO(srcnode), srcnode->mn_flags);
3783 if (rc != MDB_SUCCESS)
3788 DPRINTF("dst page %lu now has %u keys (%.1f%% filled)",
3789 dst->mp_page->mp_pgno, NUMKEYS(dst->mp_page), (float)PAGEFILL(txn->mt_env, dst->mp_page) / 10);
3791 /* Unlink the src page from parent.
3793 mdb_del_node(src->mp_parent, src->mp_pi, 0);
3794 if (src->mp_pi == 0) {
3796 if ((rc = mdb_update_key(src->mp_parent, 0, &key)) != MDB_SUCCESS)
3800 if (IS_LEAF(src->mp_page))
3801 txn->mt_dbs[dbi].md_leaf_pages--;
3803 txn->mt_dbs[dbi].md_branch_pages--;
3805 mpp.mp_page = src->mp_parent;
3806 dh = (MDB_dhead *)src->mp_parent;
3808 mpp.mp_parent = dh->md_parent;
3809 mpp.mp_pi = dh->md_pi;
3811 return mdb_rebalance(txn, dbi, &mpp);
3814 #define FILL_THRESHOLD 250
3817 mdb_rebalance(MDB_txn *txn, MDB_dbi dbi, MDB_pageparent *mpp)
3822 indx_t si = 0, di = 0;
3825 assert(txn != NULL);
3826 assert(mpp != NULL);
3828 DPRINTF("rebalancing %s page %lu (has %u keys, %.1f%% full)",
3829 IS_LEAF(mpp->mp_page) ? "leaf" : "branch",
3830 mpp->mp_page->mp_pgno, NUMKEYS(mpp->mp_page), (float)PAGEFILL(txn->mt_env, mpp->mp_page) / 10);
3832 if (PAGEFILL(txn->mt_env, mpp->mp_page) >= FILL_THRESHOLD) {
3833 DPRINTF("no need to rebalance page %lu, above fill threshold",
3834 mpp->mp_page->mp_pgno);
3838 if (mpp->mp_parent == NULL) {
3839 if (NUMKEYS(mpp->mp_page) == 0) {
3840 DPUTS("tree is completely empty");
3841 txn->mt_dbs[dbi].md_root = P_INVALID;
3842 txn->mt_dbs[dbi].md_depth = 0;
3843 txn->mt_dbs[dbi].md_leaf_pages = 0;
3844 mdb_midl_append(txn->mt_free_pgs, mpp->mp_page->mp_pgno);
3845 } else if (IS_BRANCH(mpp->mp_page) && NUMKEYS(mpp->mp_page) == 1) {
3846 DPUTS("collapsing root page!");
3847 mdb_midl_append(txn->mt_free_pgs, mpp->mp_page->mp_pgno);
3848 txn->mt_dbs[dbi].md_root = NODEPGNO(NODEPTR(mpp->mp_page, 0));
3849 if ((rc = mdb_get_page(txn, txn->mt_dbs[dbi].md_root, &root)))
3851 txn->mt_dbs[dbi].md_depth--;
3852 txn->mt_dbs[dbi].md_branch_pages--;
3854 DPUTS("root page doesn't need rebalancing");
3858 /* The parent (branch page) must have at least 2 pointers,
3859 * otherwise the tree is invalid.
3861 assert(NUMKEYS(mpp->mp_parent) > 1);
3863 /* Leaf page fill factor is below the threshold.
3864 * Try to move keys from left or right neighbor, or
3865 * merge with a neighbor page.
3870 if (mpp->mp_pi == 0) {
3871 /* We're the leftmost leaf in our parent.
3873 DPUTS("reading right neighbor");
3874 node = NODEPTR(mpp->mp_parent, mpp->mp_pi + 1);
3875 if ((rc = mdb_get_page(txn, NODEPGNO(node), &npp.mp_page)))
3877 npp.mp_pi = mpp->mp_pi + 1;
3879 di = NUMKEYS(mpp->mp_page);
3881 /* There is at least one neighbor to the left.
3883 DPUTS("reading left neighbor");
3884 node = NODEPTR(mpp->mp_parent, mpp->mp_pi - 1);
3885 if ((rc = mdb_get_page(txn, NODEPGNO(node), &npp.mp_page)))
3887 npp.mp_pi = mpp->mp_pi - 1;
3888 si = NUMKEYS(npp.mp_page) - 1;
3891 npp.mp_parent = mpp->mp_parent;
3893 DPRINTF("found neighbor page %lu (%u keys, %.1f%% full)",
3894 npp.mp_page->mp_pgno, NUMKEYS(npp.mp_page), (float)PAGEFILL(txn->mt_env, npp.mp_page) / 10);
3896 /* If the neighbor page is above threshold and has at least two
3897 * keys, move one key from it.
3899 * Otherwise we should try to merge them.
3901 if (PAGEFILL(txn->mt_env, npp.mp_page) >= FILL_THRESHOLD && NUMKEYS(npp.mp_page) >= 2)
3902 return mdb_move_node(txn, dbi, &npp, si, mpp, di);
3903 else { /* FIXME: if (has_enough_room()) */
3904 if (mpp->mp_pi == 0)
3905 return mdb_merge(txn, dbi, &npp, mpp);
3907 return mdb_merge(txn, dbi, mpp, &npp);
3912 mdb_del0(MDB_cursor *mc, unsigned int ki, MDB_pageparent *mpp, MDB_node *leaf)
3916 /* add overflow pages to free list */
3917 if (!IS_LEAF2(mpp->mp_page) && F_ISSET(leaf->mn_flags, F_BIGDATA)) {
3921 memcpy(&pg, NODEDATA(leaf), sizeof(pg));
3922 ovpages = OVPAGES(NODEDSZ(leaf), mc->mc_txn->mt_env->me_psize);
3923 for (i=0; i<ovpages; i++) {
3924 DPRINTF("freed ov page %lu", pg);
3925 mdb_midl_append(mc->mc_txn->mt_free_pgs, pg);
3929 mdb_del_node(mpp->mp_page, ki, mc->mc_txn->mt_dbs[mc->mc_dbi].md_pad);
3930 mc->mc_txn->mt_dbs[mc->mc_dbi].md_entries--;
3931 rc = mdb_rebalance(mc->mc_txn, mc->mc_dbi, mpp);
3932 if (rc != MDB_SUCCESS)
3933 mc->mc_txn->mt_flags |= MDB_TXN_ERROR;
3939 mdb_del(MDB_txn *txn, MDB_dbi dbi,
3940 MDB_val *key, MDB_val *data)
3945 MDB_val rdata, *xdata;
3949 assert(key != NULL);
3951 DPRINTF("====> delete db %u key [%s]", dbi, DKEY(key));
3953 if (txn == NULL || !dbi || dbi >= txn->mt_numdbs)
3956 if (F_ISSET(txn->mt_flags, MDB_TXN_RDONLY)) {
3960 if (key->mv_size == 0 || key->mv_size > MAXKEYSIZE) {
3967 if (txn->mt_dbs[dbi].md_flags & MDB_DUPSORT) {
3968 mc.mc_xcursor = &mx;
3969 mdb_xcursor_init0(&mc);
3971 mc.mc_xcursor = NULL;
3983 rc = mdb_cursor_set(&mc, key, xdata, op, &exact);
3985 rc = mdb_cursor_del(&mc, data ? 0 : MDB_NODUPDATA);
3989 /* Split page <*mpp>, and insert <key,(data|newpgno)> in either left or
3990 * right sibling, at index <*newindxp> (as if unsplit). Updates *mpp and
3991 * *newindxp with the actual values after split, ie if *mpp and *newindxp
3992 * refer to a node in the new right sibling page.
3995 mdb_split(MDB_txn *txn, MDB_dbi dbi, MDB_page **mpp, unsigned int *newindxp,
3996 MDB_val *newkey, MDB_val *newdata, pgno_t newpgno)
3999 int rc = MDB_SUCCESS, ins_new = 0;
4002 unsigned int i, j, split_indx, nkeys, pmax;
4004 MDB_val sepkey, rkey, rdata;
4005 MDB_page *copy, *cptr;
4006 MDB_dpage *mdp, *rdp, *pdp;
4010 assert(txn != NULL);
4012 dh = ((MDB_dhead *)*mpp) - 1;
4013 mdp = (MDB_dpage *)dh;
4014 newindx = *newindxp;
4016 DPRINTF("-----> splitting %s page %lu and adding [%s] at index %i",
4017 IS_LEAF(&mdp->p) ? "leaf" : "branch", mdp->p.mp_pgno,
4018 DKEY(newkey), *newindxp);
4020 if (mdp->h.md_parent == NULL) {
4021 if ((pdp = mdb_new_page(txn, dbi, P_BRANCH, 1)) == NULL)
4024 mdp->h.md_parent = &pdp->p;
4025 txn->mt_dbs[dbi].md_root = pdp->p.mp_pgno;
4026 DPRINTF("root split! new root = %lu", pdp->p.mp_pgno);
4027 txn->mt_dbs[dbi].md_depth++;
4029 /* Add left (implicit) pointer. */
4030 if ((rc = mdb_add_node(txn, dbi, &pdp->p, 0, NULL, NULL,
4031 mdp->p.mp_pgno, 0)) != MDB_SUCCESS)
4034 DPRINTF("parent branch page is %lu", mdp->h.md_parent->mp_pgno);
4037 /* Create a right sibling. */
4038 if ((rdp = mdb_new_page(txn, dbi, mdp->p.mp_flags, 1)) == NULL)
4040 rdp->h.md_parent = mdp->h.md_parent;
4041 rdp->h.md_pi = mdp->h.md_pi + 1;
4042 DPRINTF("new right sibling: page %lu", rdp->p.mp_pgno);
4044 nkeys = NUMKEYS(&mdp->p);
4045 split_indx = nkeys / 2 + 1;
4047 if (IS_LEAF2(&rdp->p)) {
4050 unsigned int lsize, rsize, ksize;
4051 /* Move half of the keys to the right sibling */
4053 x = *newindxp - split_indx;
4054 ksize = txn->mt_dbs[dbi].md_pad;
4055 split = LEAF2KEY(&mdp->p, split_indx, ksize);
4056 rsize = (nkeys - split_indx) * ksize;
4057 lsize = (nkeys - split_indx) * sizeof(indx_t);
4058 mdp->p.mp_lower -= lsize;
4059 rdp->p.mp_lower += lsize;
4060 mdp->p.mp_upper += rsize - lsize;
4061 rdp->p.mp_upper -= rsize - lsize;
4062 sepkey.mv_size = ksize;
4063 if (newindx == split_indx) {
4064 sepkey.mv_data = newkey->mv_data;
4066 sepkey.mv_data = split;
4069 ins = LEAF2KEY(&mdp->p, *newindxp, ksize);
4070 memcpy(&rdp->p.mp_ptrs, split, rsize);
4071 sepkey.mv_data = &rdp->p.mp_ptrs;
4072 memmove(ins+ksize, ins, (split_indx - *newindxp) * ksize);
4073 memcpy(ins, newkey->mv_data, ksize);
4074 mdp->p.mp_lower += sizeof(indx_t);
4075 mdp->p.mp_upper -= ksize - sizeof(indx_t);
4078 memcpy(&rdp->p.mp_ptrs, split, x * ksize);
4079 ins = LEAF2KEY(&rdp->p, x, ksize);
4080 memcpy(ins, newkey->mv_data, ksize);
4081 memcpy(ins+ksize, split + x * ksize, rsize - x * ksize);
4082 rdp->p.mp_lower += sizeof(indx_t);
4083 rdp->p.mp_upper -= ksize - sizeof(indx_t);
4090 /* For leaf pages, check the split point based on what
4091 * fits where, since otherwise add_node can fail.
4093 if (IS_LEAF(&mdp->p)) {
4094 unsigned int psize, nsize;
4095 /* Maximum free space in an empty page */
4096 pmax = txn->mt_env->me_psize - PAGEHDRSZ;
4097 nsize = mdb_leaf_size(txn->mt_env, newkey, newdata);
4098 if (newindx < split_indx) {
4100 for (i=0; i<split_indx; i++) {
4101 node = NODEPTR(&mdp->p, i);
4102 psize += NODESIZE + NODEKSZ(node) + sizeof(indx_t);
4103 if (F_ISSET(node->mn_flags, F_BIGDATA))
4104 psize += sizeof(pgno_t);
4106 psize += NODEDSZ(node);
4114 for (i=nkeys-1; i>=split_indx; i--) {
4115 node = NODEPTR(&mdp->p, i);
4116 psize += NODESIZE + NODEKSZ(node) + sizeof(indx_t);
4117 if (F_ISSET(node->mn_flags, F_BIGDATA))
4118 psize += sizeof(pgno_t);
4120 psize += NODEDSZ(node);
4129 /* First find the separating key between the split pages.
4131 if (newindx == split_indx) {
4132 sepkey.mv_size = newkey->mv_size;
4133 sepkey.mv_data = newkey->mv_data;
4135 node = NODEPTR(&mdp->p, split_indx);
4136 sepkey.mv_size = node->mn_ksize;
4137 sepkey.mv_data = NODEKEY(node);
4141 DPRINTF("separator is [%s]", DKEY(&sepkey));
4143 /* Copy separator key to the parent.
4145 if (SIZELEFT(rdp->h.md_parent) < mdb_branch_size(txn->mt_env, &sepkey)) {
4146 rc = mdb_split(txn, dbi, &rdp->h.md_parent, &rdp->h.md_pi,
4147 &sepkey, NULL, rdp->p.mp_pgno);
4149 /* Right page might now have changed parent.
4150 * Check if left page also changed parent.
4152 if (rdp->h.md_parent != mdp->h.md_parent &&
4153 mdp->h.md_pi >= NUMKEYS(mdp->h.md_parent)) {
4154 mdp->h.md_parent = rdp->h.md_parent;
4155 mdp->h.md_pi = rdp->h.md_pi - 1;
4158 rc = mdb_add_node(txn, dbi, rdp->h.md_parent, rdp->h.md_pi,
4159 &sepkey, NULL, rdp->p.mp_pgno, 0);
4161 if (IS_LEAF2(&rdp->p)) {
4164 if (rc != MDB_SUCCESS) {
4168 /* Move half of the keys to the right sibling. */
4169 if ((copy = malloc(txn->mt_env->me_psize)) == NULL)
4172 copy->mp_pgno = mdp->p.mp_pgno;
4173 copy->mp_flags = mdp->p.mp_flags;
4174 copy->mp_lower = PAGEHDRSZ;
4175 copy->mp_upper = txn->mt_env->me_psize;
4177 for (i = j = 0; i <= nkeys; j++) {
4178 if (i == split_indx) {
4179 /* Insert in right sibling. */
4180 /* Reset insert index for right sibling. */
4181 j = (i == newindx && ins_new);
4185 if (i == newindx && !ins_new) {
4186 /* Insert the original entry that caused the split. */
4187 rkey.mv_data = newkey->mv_data;
4188 rkey.mv_size = newkey->mv_size;
4189 if (IS_LEAF(&mdp->p)) {
4190 rdata.mv_data = newdata->mv_data;
4191 rdata.mv_size = newdata->mv_size;
4198 /* Update page and index for the new key. */
4200 if (cptr == &rdp->p)
4202 } else if (i == nkeys) {
4205 node = NODEPTR(&mdp->p, i);
4206 rkey.mv_data = NODEKEY(node);
4207 rkey.mv_size = node->mn_ksize;
4208 if (IS_LEAF(&mdp->p)) {
4209 rdata.mv_data = NODEDATA(node);
4210 rdata.mv_size = NODEDSZ(node);
4212 pgno = NODEPGNO(node);
4213 flags = node->mn_flags;
4218 if (!IS_LEAF(&mdp->p) && j == 0) {
4219 /* First branch index doesn't need key data. */
4223 rc = mdb_add_node(txn, dbi, cptr, j, &rkey, &rdata, pgno, flags);
4225 nkeys = NUMKEYS(copy);
4226 for (i=0; i<nkeys; i++)
4227 mdp->p.mp_ptrs[i] = copy->mp_ptrs[i];
4228 mdp->p.mp_lower = copy->mp_lower;
4229 mdp->p.mp_upper = copy->mp_upper;
4230 memcpy(NODEPTR(&mdp->p, nkeys-1), NODEPTR(copy, nkeys-1),
4231 txn->mt_env->me_psize - copy->mp_upper);
4238 mdb_put(MDB_txn *txn, MDB_dbi dbi,
4239 MDB_val *key, MDB_val *data, unsigned int flags)
4244 assert(key != NULL);
4245 assert(data != NULL);
4247 if (txn == NULL || !dbi || dbi >= txn->mt_numdbs)
4250 if (F_ISSET(txn->mt_flags, MDB_TXN_RDONLY)) {
4254 if (key->mv_size == 0 || key->mv_size > MAXKEYSIZE) {
4258 if ((flags & (MDB_NOOVERWRITE|MDB_NODUPDATA)) != flags)
4265 if (txn->mt_dbs[dbi].md_flags & MDB_DUPSORT) {
4266 mc.mc_xcursor = &mx;
4267 mdb_xcursor_init0(&mc);
4269 mc.mc_xcursor = NULL;
4271 return mdb_cursor_put(&mc, key, data, flags);
4275 mdb_env_set_flags(MDB_env *env, unsigned int flag, int onoff)
4277 #define CHANGEABLE (MDB_NOSYNC)
4278 if ((flag & CHANGEABLE) != flag)
4281 env->me_flags |= flag;
4283 env->me_flags &= ~flag;
4288 mdb_env_get_flags(MDB_env *env, unsigned int *arg)
4293 *arg = env->me_flags;
4298 mdb_env_get_path(MDB_env *env, const char **arg)
4303 *arg = env->me_path;
4308 mdb_stat0(MDB_env *env, MDB_db *db, MDB_stat *arg)
4310 arg->ms_psize = env->me_psize;
4311 arg->ms_depth = db->md_depth;
4312 arg->ms_branch_pages = db->md_branch_pages;
4313 arg->ms_leaf_pages = db->md_leaf_pages;
4314 arg->ms_overflow_pages = db->md_overflow_pages;
4315 arg->ms_entries = db->md_entries;
4320 mdb_env_stat(MDB_env *env, MDB_stat *arg)
4324 if (env == NULL || arg == NULL)
4327 mdb_env_read_meta(env, &toggle);
4329 return mdb_stat0(env, &env->me_metas[toggle]->mm_dbs[MAIN_DBI], arg);
4333 mdb_default_cmp(MDB_txn *txn, MDB_dbi dbi)
4335 if (txn->mt_dbs[dbi].md_flags & (MDB_REVERSEKEY
4336 #if __BYTE_ORDER == __LITTLE_ENDIAN
4340 txn->mt_dbxs[dbi].md_cmp = memnrcmp;
4342 txn->mt_dbxs[dbi].md_cmp = memncmp;
4344 if (txn->mt_dbs[dbi].md_flags & MDB_DUPSORT) {
4345 if (txn->mt_dbs[dbi].md_flags & MDB_INTEGERDUP) {
4346 if (txn->mt_dbs[dbi].md_flags & MDB_DUPFIXED)
4347 txn->mt_dbxs[dbi].md_dcmp = intcmp;
4349 #if __BYTE_ORDER == __LITTLE_ENDIAN
4350 txn->mt_dbxs[dbi].md_dcmp = memnrcmp;
4352 txn->mt_dbxs[dbi].md_dcmp = memncmp;
4354 } else if (txn->mt_dbs[dbi].md_flags & MDB_REVERSEDUP) {
4355 txn->mt_dbxs[dbi].md_dcmp = memnrcmp;
4357 txn->mt_dbxs[dbi].md_dcmp = memncmp;
4360 txn->mt_dbxs[dbi].md_dcmp = NULL;
4364 int mdb_open(MDB_txn *txn, const char *name, unsigned int flags, MDB_dbi *dbi)
4371 if (txn->mt_dbxs[FREE_DBI].md_cmp == NULL) {
4372 mdb_default_cmp(txn, FREE_DBI);
4378 if (flags & (MDB_DUPSORT|MDB_REVERSEKEY|MDB_INTEGERKEY))
4379 txn->mt_dbs[MAIN_DBI].md_flags |= (flags & (MDB_DUPSORT|MDB_REVERSEKEY|MDB_INTEGERKEY));
4380 mdb_default_cmp(txn, MAIN_DBI);
4384 if (txn->mt_dbxs[MAIN_DBI].md_cmp == NULL) {
4385 mdb_default_cmp(txn, MAIN_DBI);
4388 /* Is the DB already open? */
4390 for (i=2; i<txn->mt_numdbs; i++) {
4391 if (len == txn->mt_dbxs[i].md_name.mv_size &&
4392 !strncmp(name, txn->mt_dbxs[i].md_name.mv_data, len)) {
4398 if (txn->mt_numdbs >= txn->mt_env->me_maxdbs - 1)
4401 /* Find the DB info */
4403 key.mv_data = (void *)name;
4404 rc = mdb_get(txn, MAIN_DBI, &key, &data);
4406 /* Create if requested */
4407 if (rc == MDB_NOTFOUND && (flags & MDB_CREATE)) {
4410 data.mv_size = sizeof(MDB_db);
4411 data.mv_data = &dummy;
4412 memset(&dummy, 0, sizeof(dummy));
4413 dummy.md_root = P_INVALID;
4414 dummy.md_flags = flags & 0xffff;
4416 mc.mc_dbi = MAIN_DBI;
4418 rc = mdb_cursor_put(&mc, &key, &data, F_SUBDATA);
4422 /* OK, got info, add to table */
4423 if (rc == MDB_SUCCESS) {
4424 txn->mt_dbxs[txn->mt_numdbs].md_name.mv_data = strdup(name);
4425 txn->mt_dbxs[txn->mt_numdbs].md_name.mv_size = len;
4426 txn->mt_dbxs[txn->mt_numdbs].md_rel = NULL;
4427 txn->mt_dbxs[txn->mt_numdbs].md_parent = MAIN_DBI;
4428 txn->mt_dbxs[txn->mt_numdbs].md_dirty = dirty;
4429 memcpy(&txn->mt_dbs[txn->mt_numdbs], data.mv_data, sizeof(MDB_db));
4430 *dbi = txn->mt_numdbs;
4431 txn->mt_env->me_dbs[0][txn->mt_numdbs] = txn->mt_dbs[txn->mt_numdbs];
4432 txn->mt_env->me_dbs[1][txn->mt_numdbs] = txn->mt_dbs[txn->mt_numdbs];
4433 mdb_default_cmp(txn, txn->mt_numdbs);
4440 int mdb_stat(MDB_txn *txn, MDB_dbi dbi, MDB_stat *arg)
4442 if (txn == NULL || arg == NULL || dbi >= txn->mt_numdbs)
4445 return mdb_stat0(txn->mt_env, &txn->mt_dbs[dbi], arg);
4448 void mdb_close(MDB_txn *txn, MDB_dbi dbi)
4451 if (dbi <= MAIN_DBI || dbi >= txn->mt_numdbs)
4453 ptr = txn->mt_dbxs[dbi].md_name.mv_data;
4454 txn->mt_dbxs[dbi].md_name.mv_data = NULL;
4455 txn->mt_dbxs[dbi].md_name.mv_size = 0;
4459 int mdb_set_compare(MDB_txn *txn, MDB_dbi dbi, MDB_cmp_func *cmp)
4461 if (txn == NULL || !dbi || dbi >= txn->mt_numdbs)
4464 txn->mt_dbxs[dbi].md_cmp = cmp;
4468 int mdb_set_dupsort(MDB_txn *txn, MDB_dbi dbi, MDB_cmp_func *cmp)
4470 if (txn == NULL || !dbi || dbi >= txn->mt_numdbs)
4473 txn->mt_dbxs[dbi].md_dcmp = cmp;
4477 int mdb_set_relfunc(MDB_txn *txn, MDB_dbi dbi, MDB_rel_func *rel)
4479 if (txn == NULL || !dbi || dbi >= txn->mt_numdbs)
4482 txn->mt_dbxs[dbi].md_rel = rel;