From 17c09fa476a7dbd49aca5e4caf0384cb1c3d244a Mon Sep 17 00:00:00 2001 From: Howard Chu Date: Wed, 11 Jun 2014 02:27:30 -0700 Subject: [PATCH] ITS#7875 fix #7681 regression Due to commit 18a07eb7c2dc33372455a6040984cd6b699b41a5 --- libraries/liblmdb/mdb.c | 2 +- libraries/libmdb/mdb.c | 3678 +++++++++++++++++++++++++++++++++++++++ 2 files changed, 3679 insertions(+), 1 deletion(-) create mode 100644 libraries/libmdb/mdb.c diff --git a/libraries/liblmdb/mdb.c b/libraries/liblmdb/mdb.c index 40e68de..4377ee8 100644 --- a/libraries/liblmdb/mdb.c +++ b/libraries/liblmdb/mdb.c @@ -5421,7 +5421,7 @@ mdb_cursor_set(MDB_cursor *mc, MDB_val *key, MDB_val *data, if (!mc->mc_top) { /* There are no other pages */ mc->mc_ki[mc->mc_top] = 0; - if (op == MDB_SET_RANGE) { + if (op == MDB_SET_RANGE && !exactp) { rc = 0; goto set1; } else diff --git a/libraries/libmdb/mdb.c b/libraries/libmdb/mdb.c new file mode 100644 index 0000000..bd39a20 --- /dev/null +++ b/libraries/libmdb/mdb.c @@ -0,0 +1,3678 @@ +/* mdb.c - memory-mapped database library */ +/* + * Copyright 2011 Howard Chu, Symas Corp. + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted only as authorized by the OpenLDAP + * Public License. + * + * A copy of this license is available in the file LICENSE in the + * top-level directory of the distribution or, alternatively, at + * . + * + * This code is derived from btree.c written by Martin Hedenfalk. + * + * Copyright (c) 2009, 2010 Martin Hedenfalk + * + * Permission to use, copy, modify, and distribute this software for any + * purpose with or without fee is hereby granted, provided that the above + * copyright notice and this permission notice appear in all copies. + * + * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES + * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR + * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES + * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN + * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF + * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. + */ +#include +#include +#include +#include +#include +#ifdef HAVE_SYS_FILE_H +#include +#endif +#include + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "mdb.h" + +#define ULONG unsigned long +typedef ULONG pgno_t; + +#include "midl.h" + +/* Note: If O_DSYNC is undefined but exists in /usr/include, + * preferably set some compiler flag to get the definition. + * Otherwise compile with the less efficient -DMDB_DSYNC=O_SYNC. + */ +#ifndef MDB_DSYNC +# define MDB_DSYNC O_DSYNC +#endif + +#ifndef DEBUG +#define DEBUG 1 +#endif + +#if !(__STDC_VERSION__ >= 199901L || defined(__GNUC__)) +# define DPRINTF (void) /* Vararg macros may be unsupported */ +#elif DEBUG +# define DPRINTF(fmt, ...) /* Requires 2 or more args */ \ + fprintf(stderr, "%s:%d: " fmt "\n", __func__, __LINE__, __VA_ARGS__) +#else +# define DPRINTF(fmt, ...) ((void) 0) +#endif +#define DPUTS(arg) DPRINTF("%s", arg) + +#define PAGESIZE 4096 +#define MDB_MINKEYS 2 +#define MDB_MAGIC 0xBEEFC0DE +#define MDB_VERSION 1 +#define MAXKEYSIZE 511 +#if DEBUG +#define KBUF (MAXKEYSIZE*2+1) +#define DKBUF char kbuf[KBUF] +#define DKEY(x) mdb_dkey(x, kbuf) +#else +#define DKBUF +#define DKEY(x) +#endif + +#define P_INVALID (~0UL) + +#define F_ISSET(w, f) (((w) & (f)) == (f)) + +typedef uint16_t indx_t; + +#define DEFAULT_READERS 126 +#define DEFAULT_MAPSIZE 1048576 + +/* Lock descriptor stuff */ +#ifndef CACHELINE +#define CACHELINE 64 /* most CPUs. Itanium uses 128 */ +#endif + +typedef struct MDB_rxbody { + ULONG mrb_txnid; + pid_t mrb_pid; + pthread_t mrb_tid; +} MDB_rxbody; + +typedef struct MDB_reader { + union { + MDB_rxbody mrx; +#define mr_txnid mru.mrx.mrb_txnid +#define mr_pid mru.mrx.mrb_pid +#define mr_tid mru.mrx.mrb_tid + /* cache line alignment */ + char pad[(sizeof(MDB_rxbody)+CACHELINE-1) & ~(CACHELINE-1)]; + } mru; +} MDB_reader; + +typedef struct MDB_txbody { + uint32_t mtb_magic; + uint32_t mtb_version; + pthread_mutex_t mtb_mutex; + ULONG mtb_txnid; + uint32_t mtb_numreaders; + uint32_t mtb_me_toggle; +} MDB_txbody; + +typedef struct MDB_txninfo { + union { + MDB_txbody mtb; +#define mti_magic mt1.mtb.mtb_magic +#define mti_version mt1.mtb.mtb_version +#define mti_mutex mt1.mtb.mtb_mutex +#define mti_txnid mt1.mtb.mtb_txnid +#define mti_numreaders mt1.mtb.mtb_numreaders +#define mti_me_toggle mt1.mtb.mtb_me_toggle + char pad[(sizeof(MDB_txbody)+CACHELINE-1) & ~(CACHELINE-1)]; + } mt1; + union { + pthread_mutex_t mt2_wmutex; +#define mti_wmutex mt2.mt2_wmutex + char pad[(sizeof(pthread_mutex_t)+CACHELINE-1) & ~(CACHELINE-1)]; + } mt2; + MDB_reader mti_readers[1]; +} MDB_txninfo; + +/* Common header for all page types. Overflow pages + * occupy a number of contiguous pages with no + * headers on any page after the first. + */ +typedef struct MDB_page { /* represents a page of storage */ +#define mp_pgno mp_p.p_pgno + union padded { + pgno_t p_pgno; /* page number */ + void * p_align; /* for IL32P64 */ + } mp_p; +#define P_BRANCH 0x01 /* branch page */ +#define P_LEAF 0x02 /* leaf page */ +#define P_OVERFLOW 0x04 /* overflow page */ +#define P_META 0x08 /* meta page */ +#define P_DIRTY 0x10 /* dirty page */ +#define P_LEAF2 0x20 /* DB with small, fixed size keys and no data */ + uint32_t mp_flags; +#define mp_lower mp_pb.pb.pb_lower +#define mp_upper mp_pb.pb.pb_upper +#define mp_pages mp_pb.pb_pages + union page_bounds { + struct { + indx_t pb_lower; /* lower bound of free space */ + indx_t pb_upper; /* upper bound of free space */ + } pb; + uint32_t pb_pages; /* number of overflow pages */ + } mp_pb; + indx_t mp_ptrs[1]; /* dynamic size */ +} MDB_page; + +#define PAGEHDRSZ ((unsigned) offsetof(MDB_page, mp_ptrs)) + +#define NUMKEYS(p) (((p)->mp_lower - PAGEHDRSZ) >> 1) +#define SIZELEFT(p) (indx_t)((p)->mp_upper - (p)->mp_lower) +#define PAGEFILL(env, p) (1000L * ((env)->me_psize - PAGEHDRSZ - SIZELEFT(p)) / \ + ((env)->me_psize - PAGEHDRSZ)) +#define IS_LEAF(p) F_ISSET((p)->mp_flags, P_LEAF) +#define IS_LEAF2(p) F_ISSET((p)->mp_flags, P_LEAF2) +#define IS_BRANCH(p) F_ISSET((p)->mp_flags, P_BRANCH) +#define IS_OVERFLOW(p) F_ISSET((p)->mp_flags, P_OVERFLOW) + +#define OVPAGES(size, psize) ((PAGEHDRSZ-1 + (size)) / (psize) + 1) + +typedef struct MDB_db { + uint32_t md_pad; /* also ksize for LEAF2 pages */ + uint16_t md_flags; + uint16_t md_depth; + ULONG md_branch_pages; + ULONG md_leaf_pages; + ULONG md_overflow_pages; + ULONG md_entries; + pgno_t md_root; +} MDB_db; + +#define FREE_DBI 0 +#define MAIN_DBI 1 + +typedef struct MDB_meta { /* meta (footer) page content */ + uint32_t mm_magic; + uint32_t mm_version; + void *mm_address; /* address for fixed mapping */ + size_t mm_mapsize; /* size of mmap region */ + MDB_db mm_dbs[2]; /* first is free space, 2nd is main db */ +#define mm_psize mm_dbs[0].md_pad +#define mm_flags mm_dbs[0].md_flags + pgno_t mm_last_pg; /* last used page in file */ + ULONG mm_txnid; /* txnid that committed this page */ +} MDB_meta; + +typedef struct MDB_dhead { /* a dirty page */ + MDB_page *md_parent; + unsigned md_pi; /* parent index */ + int md_num; +} MDB_dhead; + +typedef struct MDB_dpage { + MDB_dhead h; + MDB_page p; +} MDB_dpage; + +typedef struct MDB_oldpages { + struct MDB_oldpages *mo_next; + ULONG mo_txnid; + pgno_t mo_pages[1]; /* dynamic */ +} MDB_oldpages; + +typedef struct MDB_pageparent { + MDB_page *mp_page; + MDB_page *mp_parent; + unsigned mp_pi; +} MDB_pageparent; + +static MDB_dpage *mdb_alloc_page(MDB_txn *txn, MDB_page *parent, unsigned int parent_idx, int num); +static int mdb_touch(MDB_txn *txn, MDB_pageparent *mp); + +typedef struct MDB_ppage { /* ordered list of pages */ + MDB_page *mp_page; + unsigned int mp_ki; /* cursor index on page */ +} MDB_ppage; + +#define CURSOR_TOP(c) (&(c)->mc_stack[(c)->mc_snum-1]) +#define CURSOR_PARENT(c) (&(c)->mc_stack[(c)->mc_snum-2]) + +struct MDB_xcursor; + +struct MDB_cursor { + MDB_txn *mc_txn; + MDB_ppage mc_stack[32]; /* stack of parent pages */ + unsigned int mc_snum; /* number of pushed pages */ + MDB_dbi mc_dbi; + short mc_initialized; /* 1 if initialized */ + short mc_eof; /* 1 if end is reached */ + struct MDB_xcursor *mc_xcursor; +}; + +#define METADATA(p) ((void *)((char *)(p) + PAGEHDRSZ)) + +typedef struct MDB_node { +#define mn_pgno mn_p.np_pgno +#define mn_dsize mn_p.np_dsize + union { + pgno_t np_pgno; /* child page number */ + uint32_t np_dsize; /* leaf data size */ + } mn_p; + unsigned int mn_flags:4; + unsigned int mn_ksize:12; /* key size */ +#define F_BIGDATA 0x01 /* data put on overflow page */ +#define F_SUBDATA 0x02 /* data is a sub-database */ +#define F_DUPDATA 0x04 /* data has duplicates */ + char mn_data[1]; +} MDB_node; + +typedef struct MDB_dbx { + MDB_val md_name; + MDB_cmp_func *md_cmp; /* user compare function */ + MDB_cmp_func *md_dcmp; /* user dupsort function */ + MDB_rel_func *md_rel; /* user relocate function */ + MDB_dbi md_parent; + unsigned int md_dirty; +} MDB_dbx; + +struct MDB_txn { + pgno_t mt_next_pgno; /* next unallocated page */ + ULONG mt_txnid; + ULONG mt_oldest; + MDB_env *mt_env; + pgno_t *mt_free_pgs; /* this is an IDL */ + union { + MIDL2 *dirty_list; /* modified pages */ + MDB_reader *reader; + } mt_u; + MDB_dbx *mt_dbxs; /* array */ + MDB_db *mt_dbs; + unsigned int mt_numdbs; + +#define MDB_TXN_RDONLY 0x01 /* read-only transaction */ +#define MDB_TXN_ERROR 0x02 /* an error has occurred */ +#define MDB_TXN_METOGGLE 0x04 /* used meta page 1 */ + unsigned int mt_flags; +}; + +/* Context for sorted-dup records */ +typedef struct MDB_xcursor { + MDB_cursor mx_cursor; + MDB_txn mx_txn; + MDB_dbx mx_dbxs[4]; + MDB_db mx_dbs[4]; +} MDB_xcursor; + +struct MDB_env { + int me_fd; + int me_lfd; + int me_mfd; /* just for writing the meta pages */ +#define MDB_FATAL_ERROR 0x80000000U + uint32_t me_flags; + uint32_t me_extrapad; /* unused for now */ + unsigned int me_maxreaders; + unsigned int me_numdbs; + unsigned int me_maxdbs; + char *me_path; + char *me_map; + MDB_txninfo *me_txns; + MDB_meta *me_metas[2]; + MDB_meta *me_meta; + MDB_txn *me_txn; /* current write transaction */ + size_t me_mapsize; + off_t me_size; /* current file size */ + pgno_t me_maxpg; /* me_mapsize / me_psize */ + unsigned int me_psize; + unsigned int me_db_toggle; + MDB_dbx *me_dbxs; /* array */ + MDB_db *me_dbs[2]; + MDB_oldpages *me_pghead; + pthread_key_t me_txkey; /* thread-key for readers */ + MDB_dpage *me_dpages; + pgno_t me_free_pgs[MDB_IDL_UM_SIZE]; + MIDL2 me_dirty_list[MDB_IDL_DB_SIZE]; +}; + +#define NODESIZE offsetof(MDB_node, mn_data) + +#define INDXSIZE(k) (NODESIZE + ((k) == NULL ? 0 : (k)->mv_size)) +#define LEAFSIZE(k, d) (NODESIZE + (k)->mv_size + (d)->mv_size) +#define NODEPTR(p, i) ((MDB_node *)((char *)(p) + (p)->mp_ptrs[i])) +#define NODEKEY(node) (void *)((node)->mn_data) +#define NODEDATA(node) (void *)((char *)(node)->mn_data + (node)->mn_ksize) +#define NODEPGNO(node) ((node)->mn_pgno) +#define NODEDSZ(node) ((node)->mn_dsize) +#define NODEKSZ(node) ((node)->mn_ksize) +#define LEAF2KEY(p, i, ks) ((char *)(p) + PAGEHDRSZ + ((i)*(ks))) + +#define MDB_SET_KEY(node, key) if (key!=NULL) {(key)->mv_size = NODEKSZ(node); (key)->mv_data = NODEKEY(node);} + +#define MDB_COMMIT_PAGES 64 /* max number of pages to write in one commit */ + +static int mdb_search_page_root(MDB_txn *txn, + MDB_dbi dbi, MDB_val *key, + MDB_cursor *cursor, int modify, + MDB_pageparent *mpp); +static int mdb_search_page(MDB_txn *txn, + MDB_dbi dbi, MDB_val *key, + MDB_cursor *cursor, int modify, + MDB_pageparent *mpp); + +static int mdb_env_read_header(MDB_env *env, MDB_meta *meta); +static int mdb_env_read_meta(MDB_env *env, int *which); +static int mdb_env_write_meta(MDB_txn *txn); +static MDB_page *mdb_get_page(MDB_txn *txn, pgno_t pgno); + +static MDB_node *mdb_search_node(MDB_txn *txn, MDB_dbi dbi, MDB_page *mp, + MDB_val *key, int *exactp, unsigned int *kip); +static int mdb_add_node(MDB_txn *txn, MDB_dbi dbi, MDB_page *mp, + indx_t indx, MDB_val *key, MDB_val *data, + pgno_t pgno, uint8_t flags); +static void mdb_del_node(MDB_page *mp, indx_t indx, int ksize); +static int mdb_del0(MDB_txn *txn, MDB_dbi dbi, unsigned int ki, + MDB_pageparent *mpp, MDB_node *leaf); +static int mdb_put0(MDB_txn *txn, MDB_dbi dbi, + MDB_val *key, MDB_val *data, unsigned int flags); +static int mdb_read_data(MDB_txn *txn, MDB_node *leaf, MDB_val *data); + +static int mdb_rebalance(MDB_txn *txn, MDB_dbi dbi, MDB_pageparent *mp); +static int mdb_update_key(MDB_page *mp, indx_t indx, MDB_val *key); +static int mdb_move_node(MDB_txn *txn, MDB_dbi dbi, + MDB_pageparent *src, indx_t srcindx, + MDB_pageparent *dst, indx_t dstindx); +static int mdb_merge(MDB_txn *txn, MDB_dbi dbi, MDB_pageparent *src, + MDB_pageparent *dst); +static int mdb_split(MDB_txn *txn, MDB_dbi dbi, MDB_page **mpp, + unsigned int *newindxp, MDB_val *newkey, + MDB_val *newdata, pgno_t newpgno); +static MDB_dpage *mdb_new_page(MDB_txn *txn, MDB_dbi dbi, uint32_t flags, int num); + +static void cursor_pop_page(MDB_cursor *cursor); +static MDB_ppage *cursor_push_page(MDB_cursor *cursor, + MDB_page *mp); + +static int mdb_sibling(MDB_cursor *cursor, int move_right); +static int mdb_cursor_next(MDB_cursor *cursor, + MDB_val *key, MDB_val *data, MDB_cursor_op op); +static int mdb_cursor_prev(MDB_cursor *cursor, + MDB_val *key, MDB_val *data, MDB_cursor_op op); +static int mdb_cursor_set(MDB_cursor *cursor, + MDB_val *key, MDB_val *data, MDB_cursor_op op, int *exactp); +static int mdb_cursor_first(MDB_cursor *cursor, + MDB_val *key, MDB_val *data); +static int mdb_cursor_last(MDB_cursor *cursor, + MDB_val *key, MDB_val *data); + +static void mdb_xcursor_init0(MDB_txn *txn, MDB_dbi dbi, MDB_xcursor *mx); +static void mdb_xcursor_init1(MDB_txn *txn, MDB_dbi dbi, MDB_xcursor *mx, MDB_node *node); +static void mdb_xcursor_fini(MDB_txn *txn, MDB_dbi dbi, MDB_xcursor *mx); + +static size_t mdb_leaf_size(MDB_env *env, MDB_val *key, + MDB_val *data); +static size_t mdb_branch_size(MDB_env *env, MDB_val *key); + +static int memncmp(const void *s1, size_t n1, + const void *s2, size_t n2); +static int memnrcmp(const void *s1, size_t n1, + const void *s2, size_t n2); + +static int +memncmp(const void *s1, size_t n1, const void *s2, size_t n2) +{ + int diff, len_diff = -1; + + if (n1 >= n2) { + len_diff = (n1 > n2); + n1 = n2; + } + diff = memcmp(s1, s2, n1); + return diff ? diff : len_diff; +} + +static int +memnrcmp(const void *s1, size_t n1, const void *s2, size_t n2) +{ + const unsigned char *p1, *p2, *p1_lim; + + if (n2 == 0) + return n1 != 0; + if (n1 == 0) + return -1; + + p1 = (const unsigned char *)s1 + n1 - 1; + p2 = (const unsigned char *)s2 + n2 - 1; + + for (p1_lim = (n1 <= n2 ? s1 : s2); *p1 == *p2; p1--, p2--) { + if (p1 == p1_lim) + return (p1 != s1) ? (p1 != p2) : (p2 != s2) ? -1 : 0; + } + return *p1 - *p2; +} + +char * +mdb_version(int *maj, int *min, int *pat) +{ + *maj = MDB_VERSION_MAJOR; + *min = MDB_VERSION_MINOR; + *pat = MDB_VERSION_PATCH; + return MDB_VERSION_STRING; +} + +static char *const errstr[] = { + "MDB_KEYEXIST: Key/data pair already exists", + "MDB_NOTFOUND: No matching key/data pair found", + "MDB_PAGE_NOTFOUND: Requested page not found", + "MDB_CORRUPTED: Located page was wrong type", + "MDB_PANIC: Update of meta page failed", + "MDB_VERSION_MISMATCH: Database environment version mismatch" +}; + +char * +mdb_strerror(int err) +{ + if (!err) + return ("Successful return: 0"); + + if (err >= MDB_KEYEXIST && err <= MDB_VERSION_MISMATCH) + return errstr[err - MDB_KEYEXIST]; + + return strerror(err); +} + +static char * +mdb_dkey(MDB_val *key, char *buf) +{ + char *ptr = buf; + unsigned char *c = key->mv_data; + unsigned int i; + if (key->mv_size > MAXKEYSIZE) + return "MAXKEYSIZE"; + for (i=0; imv_size; i++) + ptr += sprintf(ptr, "%02x", *c++); + return buf; +} + +int +mdb_cmp(MDB_txn *txn, MDB_dbi dbi, const MDB_val *a, const MDB_val *b) +{ + if (txn->mt_dbxs[dbi].md_cmp) + return txn->mt_dbxs[dbi].md_cmp(a, b); + + if (txn->mt_dbs[dbi].md_flags & (MDB_REVERSEKEY +#if __BYTE_ORDER == __LITTLE_ENDIAN + |MDB_INTEGERKEY +#endif + )) + return memnrcmp(a->mv_data, a->mv_size, b->mv_data, b->mv_size); + else + return memncmp((char *)a->mv_data, a->mv_size, b->mv_data, b->mv_size); +} + +int +mdb_dcmp(MDB_txn *txn, MDB_dbi dbi, const MDB_val *a, const MDB_val *b) +{ + if (txn->mt_dbxs[dbi].md_dcmp) + return txn->mt_dbxs[dbi].md_dcmp(a, b); + + if (txn->mt_dbs[dbi].md_flags & (0 +#if __BYTE_ORDER == __LITTLE_ENDIAN + |MDB_INTEGERDUP +#endif + )) + return memnrcmp(a->mv_data, a->mv_size, b->mv_data, b->mv_size); + else + return memncmp((char *)a->mv_data, a->mv_size, b->mv_data, b->mv_size); +} + +/* Allocate new page(s) for writing */ +static MDB_dpage * +mdb_alloc_page(MDB_txn *txn, MDB_page *parent, unsigned int parent_idx, int num) +{ + MDB_dpage *dp; + pgno_t pgno = P_INVALID; + ULONG oldest; + MIDL2 mid; + + if (txn->mt_txnid > 2) { + + oldest = txn->mt_txnid - 2; + if (!txn->mt_env->me_pghead && txn->mt_dbs[FREE_DBI].md_root != P_INVALID) { + /* See if there's anything in the free DB */ + MDB_pageparent mpp; + MDB_node *leaf; + ULONG *kptr; + + mpp.mp_parent = NULL; + mpp.mp_pi = 0; + mdb_search_page(txn, FREE_DBI, NULL, NULL, 0, &mpp); + leaf = NODEPTR(mpp.mp_page, 0); + kptr = (ULONG *)NODEKEY(leaf); + + /* It's potentially usable, unless there are still + * older readers outstanding. Grab it. + */ + if (oldest > *kptr) { + MDB_oldpages *mop; + MDB_val data; + pgno_t *idl; + + mdb_read_data(txn, leaf, &data); + idl = (ULONG *)data.mv_data; + mop = malloc(sizeof(MDB_oldpages) + MDB_IDL_SIZEOF(idl) - sizeof(pgno_t)); + mop->mo_next = txn->mt_env->me_pghead; + mop->mo_txnid = *kptr; + txn->mt_env->me_pghead = mop; + memcpy(mop->mo_pages, idl, MDB_IDL_SIZEOF(idl)); + +#if DEBUG > 1 + { + unsigned int i; + DPRINTF("IDL read txn %lu root %lu num %lu", + mop->mo_txnid, txn->mt_dbs[FREE_DBI].md_root, idl[0]); + for (i=0; imt_env->me_pghead) { + unsigned int i; + for (i=0; imt_env->me_txns->mti_numreaders; i++) { + ULONG mr = txn->mt_env->me_txns->mti_readers[i].mr_txnid; + if (!mr) continue; + if (mr < oldest) + oldest = txn->mt_env->me_txns->mti_readers[i].mr_txnid; + } + if (oldest > txn->mt_env->me_pghead->mo_txnid) { + MDB_oldpages *mop = txn->mt_env->me_pghead; + txn->mt_oldest = oldest; + if (num > 1) { + /* FIXME: For now, always use fresh pages. We + * really ought to search the free list for a + * contiguous range. + */ + ; + } else { + /* peel pages off tail, so we only have to truncate the list */ + pgno = MDB_IDL_LAST(mop->mo_pages); + if (MDB_IDL_IS_RANGE(mop->mo_pages)) { + mop->mo_pages[2]++; + if (mop->mo_pages[2] > mop->mo_pages[1]) + mop->mo_pages[0] = 0; + } else { + mop->mo_pages[0]--; + } + if (MDB_IDL_IS_ZERO(mop->mo_pages)) { + txn->mt_env->me_pghead = mop->mo_next; + free(mop); + } + } + } + } + } + + if (pgno == P_INVALID) { + /* DB size is maxed out */ + if (txn->mt_next_pgno + num >= txn->mt_env->me_maxpg) + return NULL; + } + if (txn->mt_env->me_dpages && num == 1) { + dp = txn->mt_env->me_dpages; + txn->mt_env->me_dpages = (MDB_dpage *)dp->h.md_parent; + } else { + if ((dp = malloc(txn->mt_env->me_psize * num + sizeof(MDB_dhead))) == NULL) + return NULL; + } + dp->h.md_num = num; + dp->h.md_parent = parent; + dp->h.md_pi = parent_idx; + if (pgno == P_INVALID) { + dp->p.mp_pgno = txn->mt_next_pgno; + txn->mt_next_pgno += num; + } else { + dp->p.mp_pgno = pgno; + } + mid.mid = dp->p.mp_pgno; + mid.mptr = dp; + mdb_midl2_insert(txn->mt_u.dirty_list, &mid); + + return dp; +} + +/* Touch a page: make it dirty and re-insert into tree with updated pgno. + */ +static int +mdb_touch(MDB_txn *txn, MDB_pageparent *pp) +{ + MDB_page *mp = pp->mp_page; + pgno_t pgno; + assert(txn != NULL); + assert(pp != NULL); + + if (!F_ISSET(mp->mp_flags, P_DIRTY)) { + MDB_dpage *dp; + if ((dp = mdb_alloc_page(txn, pp->mp_parent, pp->mp_pi, 1)) == NULL) + return ENOMEM; + DPRINTF("touched page %lu -> %lu", mp->mp_pgno, dp->p.mp_pgno); + mdb_midl_insert(txn->mt_free_pgs, mp->mp_pgno); + pgno = dp->p.mp_pgno; + memcpy(&dp->p, mp, txn->mt_env->me_psize); + mp = &dp->p; + mp->mp_pgno = pgno; + mp->mp_flags |= P_DIRTY; + + /* Update the page number to new touched page. */ + if (pp->mp_parent != NULL) + NODEPGNO(NODEPTR(pp->mp_parent, pp->mp_pi)) = mp->mp_pgno; + pp->mp_page = mp; + } + return 0; +} + +int +mdb_env_sync(MDB_env *env, int force) +{ + int rc = 0; + if (force || !F_ISSET(env->me_flags, MDB_NOSYNC)) { + if (fdatasync(env->me_fd)) + rc = errno; + } + return rc; +} + +int +mdb_txn_begin(MDB_env *env, int rdonly, MDB_txn **ret) +{ + MDB_txn *txn; + int rc, toggle; + + if (env->me_flags & MDB_FATAL_ERROR) { + DPUTS("mdb_txn_begin: environment had fatal error, must shutdown!"); + return MDB_PANIC; + } + if ((txn = calloc(1, sizeof(MDB_txn))) == NULL) { + DPRINTF("calloc: %s", strerror(errno)); + return ENOMEM; + } + + if (rdonly) { + txn->mt_flags |= MDB_TXN_RDONLY; + } else { + txn->mt_u.dirty_list = env->me_dirty_list; + txn->mt_u.dirty_list[0].mid = 0; + txn->mt_free_pgs = env->me_free_pgs; + txn->mt_free_pgs[0] = 0; + + pthread_mutex_lock(&env->me_txns->mti_wmutex); + env->me_txns->mti_txnid++; + } + + txn->mt_txnid = env->me_txns->mti_txnid; + if (rdonly) { + MDB_reader *r = pthread_getspecific(env->me_txkey); + if (!r) { + unsigned int i; + pthread_mutex_lock(&env->me_txns->mti_mutex); + for (i=0; ime_txns->mti_numreaders; i++) + if (env->me_txns->mti_readers[i].mr_pid == 0) + break; + if (i == env->me_maxreaders) { + pthread_mutex_unlock(&env->me_txns->mti_mutex); + return ENOSPC; + } + env->me_txns->mti_readers[i].mr_pid = getpid(); + env->me_txns->mti_readers[i].mr_tid = pthread_self(); + r = &env->me_txns->mti_readers[i]; + pthread_setspecific(env->me_txkey, r); + if (i >= env->me_txns->mti_numreaders) + env->me_txns->mti_numreaders = i+1; + pthread_mutex_unlock(&env->me_txns->mti_mutex); + } + r->mr_txnid = txn->mt_txnid; + txn->mt_u.reader = r; + } else { + env->me_txn = txn; + } + + txn->mt_env = env; + + toggle = env->me_txns->mti_me_toggle; + if ((rc = mdb_env_read_meta(env, &toggle)) != MDB_SUCCESS) { + mdb_txn_abort(txn); + return rc; + } + + /* Copy the DB arrays */ + txn->mt_numdbs = env->me_numdbs; + txn->mt_dbxs = env->me_dbxs; /* mostly static anyway */ + txn->mt_dbs = malloc(env->me_maxdbs * sizeof(MDB_db)); + memcpy(txn->mt_dbs, env->me_meta->mm_dbs, 2 * sizeof(MDB_db)); + if (txn->mt_numdbs > 2) + memcpy(txn->mt_dbs+2, env->me_dbs[env->me_db_toggle]+2, + (txn->mt_numdbs - 2) * sizeof(MDB_db)); + + if (!rdonly) { + if (toggle) + txn->mt_flags |= MDB_TXN_METOGGLE; + txn->mt_next_pgno = env->me_meta->mm_last_pg+1; + } + + DPRINTF("begin transaction %lu on mdbenv %p, root page %lu", + txn->mt_txnid, (void *) env, txn->mt_dbs[MAIN_DBI].md_root); + + *ret = txn; + return MDB_SUCCESS; +} + +void +mdb_txn_abort(MDB_txn *txn) +{ + MDB_env *env; + + if (txn == NULL) + return; + + env = txn->mt_env; + DPRINTF("abort transaction %lu on mdbenv %p, root page %lu", + txn->mt_txnid, (void *) env, txn->mt_dbs[MAIN_DBI].md_root); + + free(txn->mt_dbs); + + if (F_ISSET(txn->mt_flags, MDB_TXN_RDONLY)) { + txn->mt_u.reader->mr_txnid = 0; + } else { + MDB_oldpages *mop; + MDB_dpage *dp; + unsigned int i; + + /* return all dirty pages to dpage list */ + for (i=1; i<=txn->mt_u.dirty_list[0].mid; i++) { + dp = txn->mt_u.dirty_list[i].mptr; + if (dp->h.md_num == 1) { + dp->h.md_parent = (MDB_page *)txn->mt_env->me_dpages; + txn->mt_env->me_dpages = dp; + } else { + /* large pages just get freed directly */ + free(dp); + } + } + + while ((mop = txn->mt_env->me_pghead)) { + txn->mt_env->me_pghead = mop->mo_next; + free(mop); + } + + env->me_txn = NULL; + env->me_txns->mti_txnid--; + for (i=2; ime_numdbs; i++) + env->me_dbxs[i].md_dirty = 0; + pthread_mutex_unlock(&env->me_txns->mti_wmutex); + } + + free(txn); +} + +int +mdb_txn_commit(MDB_txn *txn) +{ + int n, done; + unsigned int i; + ssize_t rc; + off_t size; + MDB_dpage *dp; + MDB_env *env; + pgno_t next; + struct iovec iov[MDB_COMMIT_PAGES]; + + assert(txn != NULL); + assert(txn->mt_env != NULL); + + env = txn->mt_env; + + if (F_ISSET(txn->mt_flags, MDB_TXN_RDONLY)) { + mdb_txn_abort(txn); + return MDB_SUCCESS; + } + + if (txn != env->me_txn) { + DPUTS("attempt to commit unknown transaction"); + mdb_txn_abort(txn); + return EINVAL; + } + + if (F_ISSET(txn->mt_flags, MDB_TXN_ERROR)) { + DPUTS("error flag is set, can't commit"); + mdb_txn_abort(txn); + return EINVAL; + } + + if (!txn->mt_u.dirty_list[0].mid) + goto done; + + DPRINTF("committing transaction %lu on mdbenv %p, root page %lu", + txn->mt_txnid, (void *) env, txn->mt_dbs[MAIN_DBI].md_root); + + /* should only be one record now */ + if (env->me_pghead) { + MDB_val key, data; + MDB_oldpages *mop; + + mop = env->me_pghead; + key.mv_size = sizeof(pgno_t); + key.mv_data = (char *)&mop->mo_txnid; + data.mv_size = MDB_IDL_SIZEOF(mop->mo_pages); + data.mv_data = mop->mo_pages; + mdb_put0(txn, FREE_DBI, &key, &data, 0); + free(env->me_pghead); + env->me_pghead = NULL; + } + /* save to free list */ + if (!MDB_IDL_IS_ZERO(txn->mt_free_pgs)) { + MDB_val key, data; + MDB_pageparent mpp; + + /* make sure last page of freeDB is touched and on freelist */ + key.mv_size = MAXKEYSIZE+1; + key.mv_data = NULL; + mpp.mp_parent = NULL; + mpp.mp_pi = 0; + mdb_search_page(txn, FREE_DBI, &key, NULL, 1, &mpp); + +#if DEBUG > 1 + { + unsigned int i; + ULONG *idl = txn->mt_free_pgs; + DPRINTF("IDL write txn %lu root %lu num %lu", + txn->mt_txnid, txn->mt_dbs[FREE_DBI].md_root, idl[0]); + for (i=0; imt_txnid; + data.mv_size = MDB_IDL_SIZEOF(txn->mt_free_pgs); + data.mv_data = txn->mt_free_pgs; + mdb_put0(txn, FREE_DBI, &key, &data, 0); + } + + /* Update DB root pointers. Their pages have already been + * touched so this is all in-place and cannot fail. + */ + { + MDB_val data; + data.mv_size = sizeof(MDB_db); + + for (i = 2; i < txn->mt_numdbs; i++) { + if (txn->mt_dbxs[i].md_dirty) { + data.mv_data = &txn->mt_dbs[i]; + mdb_put0(txn, MAIN_DBI, &txn->mt_dbxs[i].md_name, &data, 0); + } + } + } + + /* Commit up to MDB_COMMIT_PAGES dirty pages to disk until done. + */ + next = 0; + i = 1; + do { + n = 0; + done = 1; + size = 0; + for (; i<=txn->mt_u.dirty_list[0].mid; i++) { + dp = txn->mt_u.dirty_list[i].mptr; + if (dp->p.mp_pgno != next) { + if (n) { + DPRINTF("committing %u dirty pages", n); + rc = writev(env->me_fd, iov, n); + if (rc != size) { + n = errno; + if (rc > 0) + DPUTS("short write, filesystem full?"); + else + DPRINTF("writev: %s", strerror(errno)); + mdb_txn_abort(txn); + return n; + } + n = 0; + size = 0; + } + lseek(env->me_fd, dp->p.mp_pgno * env->me_psize, SEEK_SET); + next = dp->p.mp_pgno; + } + DPRINTF("committing page %lu", dp->p.mp_pgno); + iov[n].iov_len = env->me_psize * dp->h.md_num; + iov[n].iov_base = &dp->p; + size += iov[n].iov_len; + next = dp->p.mp_pgno + dp->h.md_num; + /* clear dirty flag */ + dp->p.mp_flags &= ~P_DIRTY; + if (++n >= MDB_COMMIT_PAGES) { + done = 0; + break; + } + } + + if (n == 0) + break; + + DPRINTF("committing %u dirty pages", n); + rc = writev(env->me_fd, iov, n); + if (rc != size) { + n = errno; + if (rc > 0) + DPUTS("short write, filesystem full?"); + else + DPRINTF("writev: %s", strerror(errno)); + mdb_txn_abort(txn); + return n; + } + + } while (!done); + + /* Drop the dirty pages. + */ + for (i=1; i<=txn->mt_u.dirty_list[0].mid; i++) { + dp = txn->mt_u.dirty_list[i].mptr; + if (dp->h.md_num == 1) { + dp->h.md_parent = (MDB_page *)txn->mt_env->me_dpages; + txn->mt_env->me_dpages = dp; + } else { + free(dp); + } + txn->mt_u.dirty_list[i].mid = 0; + } + + if ((n = mdb_env_sync(env, 0)) != 0 || + (n = mdb_env_write_meta(txn)) != MDB_SUCCESS) { + mdb_txn_abort(txn); + return n; + } + +done: + env->me_txn = NULL; + /* update the DB tables */ + { + int toggle = !env->me_db_toggle; + + for (i = 2; i < env->me_numdbs; i++) { + if (txn->mt_dbxs[i].md_dirty) { + env->me_dbs[toggle][i] = txn->mt_dbs[i]; + txn->mt_dbxs[i].md_dirty = 0; + } + } + for (i = env->me_numdbs; i < txn->mt_numdbs; i++) { + txn->mt_dbxs[i].md_dirty = 0; + env->me_dbxs[i] = txn->mt_dbxs[i]; + env->me_dbs[toggle][i] = txn->mt_dbs[i]; + } + env->me_db_toggle = toggle; + env->me_numdbs = txn->mt_numdbs; + + free(txn->mt_dbs); + } + + pthread_mutex_unlock(&env->me_txns->mti_wmutex); + free(txn); + + return MDB_SUCCESS; +} + +static int +mdb_env_read_header(MDB_env *env, MDB_meta *meta) +{ + char page[PAGESIZE]; + MDB_page *p; + MDB_meta *m; + int rc; + + assert(env != NULL); + + /* We don't know the page size yet, so use a minimum value. + */ + + if ((rc = pread(env->me_fd, page, PAGESIZE, 0)) == 0) { + return ENOENT; + } else if (rc != PAGESIZE) { + if (rc > 0) + errno = EINVAL; + DPRINTF("read: %s", strerror(errno)); + return errno; + } + + p = (MDB_page *)page; + + if (!F_ISSET(p->mp_flags, P_META)) { + DPRINTF("page %lu not a meta page", p->mp_pgno); + return EINVAL; + } + + m = METADATA(p); + if (m->mm_magic != MDB_MAGIC) { + DPUTS("meta has invalid magic"); + return EINVAL; + } + + if (m->mm_version != MDB_VERSION) { + DPRINTF("database is version %u, expected version %u", + m->mm_version, MDB_VERSION); + return MDB_VERSION_MISMATCH; + } + + memcpy(meta, m, sizeof(*m)); + return 0; +} + +static int +mdb_env_init_meta(MDB_env *env, MDB_meta *meta) +{ + MDB_page *p, *q; + MDB_meta *m; + int rc; + unsigned int psize; + + DPUTS("writing new meta page"); + psize = sysconf(_SC_PAGE_SIZE); + + meta->mm_magic = MDB_MAGIC; + meta->mm_version = MDB_VERSION; + meta->mm_psize = psize; + meta->mm_last_pg = 1; + meta->mm_flags = env->me_flags & 0xffff; + meta->mm_flags |= MDB_INTEGERKEY; + meta->mm_dbs[0].md_root = P_INVALID; + meta->mm_dbs[1].md_root = P_INVALID; + + p = calloc(2, psize); + p->mp_pgno = 0; + p->mp_flags = P_META; + + m = METADATA(p); + memcpy(m, meta, sizeof(*meta)); + + q = (MDB_page *)((char *)p + psize); + + q->mp_pgno = 1; + q->mp_flags = P_META; + + m = METADATA(q); + memcpy(m, meta, sizeof(*meta)); + + rc = write(env->me_fd, p, psize * 2); + free(p); + return (rc == (int)psize * 2) ? MDB_SUCCESS : errno; +} + +static int +mdb_env_write_meta(MDB_txn *txn) +{ + MDB_env *env; + MDB_meta meta, metab; + off_t off; + int rc, len, toggle; + char *ptr; + + assert(txn != NULL); + assert(txn->mt_env != NULL); + + toggle = !F_ISSET(txn->mt_flags, MDB_TXN_METOGGLE); + DPRINTF("writing meta page %d for root page %lu", + toggle, txn->mt_dbs[MAIN_DBI].md_root); + + env = txn->mt_env; + + metab.mm_txnid = env->me_metas[toggle]->mm_txnid; + metab.mm_last_pg = env->me_metas[toggle]->mm_last_pg; + + ptr = (char *)&meta; + off = offsetof(MDB_meta, mm_dbs[0].md_depth); + len = sizeof(MDB_meta) - off; + + ptr += off; + meta.mm_dbs[0] = txn->mt_dbs[0]; + meta.mm_dbs[1] = txn->mt_dbs[1]; + meta.mm_last_pg = txn->mt_next_pgno - 1; + meta.mm_txnid = txn->mt_txnid; + + if (toggle) + off += env->me_psize; + off += PAGEHDRSZ; + + /* Write to the SYNC fd */ + rc = pwrite(env->me_mfd, ptr, len, off); + if (rc != len) { + int r2; + rc = errno; + DPUTS("write failed, disk error?"); + /* On a failure, the pagecache still contains the new data. + * Write some old data back, to prevent it from being used. + * Use the non-SYNC fd; we know it will fail anyway. + */ + meta.mm_last_pg = metab.mm_last_pg; + meta.mm_txnid = metab.mm_txnid; + r2 = pwrite(env->me_fd, ptr, len, off); + env->me_flags |= MDB_FATAL_ERROR; + return rc; + } + txn->mt_env->me_txns->mti_me_toggle = toggle; + + return MDB_SUCCESS; +} + +static int +mdb_env_read_meta(MDB_env *env, int *which) +{ + int toggle = 0; + + assert(env != NULL); + + if (which) + toggle = *which; + else if (env->me_metas[0]->mm_txnid < env->me_metas[1]->mm_txnid) + toggle = 1; + + if (env->me_meta != env->me_metas[toggle]) + env->me_meta = env->me_metas[toggle]; + + DPRINTF("Using meta page %d", toggle); + + return MDB_SUCCESS; +} + +int +mdb_env_create(MDB_env **env) +{ + MDB_env *e; + + e = calloc(1, sizeof(MDB_env)); + if (!e) return ENOMEM; + + e->me_maxreaders = DEFAULT_READERS; + e->me_maxdbs = 2; + e->me_fd = -1; + e->me_lfd = -1; + e->me_mfd = -1; + *env = e; + return MDB_SUCCESS; +} + +int +mdb_env_set_mapsize(MDB_env *env, size_t size) +{ + if (env->me_map) + return EINVAL; + env->me_mapsize = size; + return MDB_SUCCESS; +} + +int +mdb_env_set_maxdbs(MDB_env *env, int dbs) +{ + env->me_maxdbs = dbs; + return MDB_SUCCESS; +} + +int +mdb_env_set_maxreaders(MDB_env *env, int readers) +{ + env->me_maxreaders = readers; + return MDB_SUCCESS; +} + +int +mdb_env_get_maxreaders(MDB_env *env, int *readers) +{ + if (!env || !readers) + return EINVAL; + *readers = env->me_maxreaders; + return MDB_SUCCESS; +} + +static int +mdb_env_open2(MDB_env *env, unsigned int flags) +{ + int i, newenv = 0; + MDB_meta meta; + MDB_page *p; + + env->me_flags = flags; + + memset(&meta, 0, sizeof(meta)); + + if ((i = mdb_env_read_header(env, &meta)) != 0) { + if (i != ENOENT) + return i; + DPUTS("new mdbenv"); + newenv = 1; + } + + if (!env->me_mapsize) { + env->me_mapsize = newenv ? DEFAULT_MAPSIZE : meta.mm_mapsize; + } + + i = MAP_SHARED; + if (meta.mm_address && (flags & MDB_FIXEDMAP)) + i |= MAP_FIXED; + env->me_map = mmap(meta.mm_address, env->me_mapsize, PROT_READ, i, + env->me_fd, 0); + if (env->me_map == MAP_FAILED) + return errno; + + if (newenv) { + meta.mm_mapsize = env->me_mapsize; + if (flags & MDB_FIXEDMAP) + meta.mm_address = env->me_map; + i = mdb_env_init_meta(env, &meta); + if (i != MDB_SUCCESS) { + munmap(env->me_map, env->me_mapsize); + return i; + } + } + env->me_psize = meta.mm_psize; + + env->me_maxpg = env->me_mapsize / env->me_psize; + + p = (MDB_page *)env->me_map; + env->me_metas[0] = METADATA(p); + env->me_metas[1] = (MDB_meta *)((char *)env->me_metas[0] + meta.mm_psize); + + if ((i = mdb_env_read_meta(env, NULL)) != 0) + return i; + + DPRINTF("opened database version %u, pagesize %u", + env->me_meta->mm_version, env->me_psize); + DPRINTF("depth: %u", env->me_meta->mm_dbs[MAIN_DBI].md_depth); + DPRINTF("entries: %lu", env->me_meta->mm_dbs[MAIN_DBI].md_entries); + DPRINTF("branch pages: %lu", env->me_meta->mm_dbs[MAIN_DBI].md_branch_pages); + DPRINTF("leaf pages: %lu", env->me_meta->mm_dbs[MAIN_DBI].md_leaf_pages); + DPRINTF("overflow pages: %lu", env->me_meta->mm_dbs[MAIN_DBI].md_overflow_pages); + DPRINTF("root: %lu", env->me_meta->mm_dbs[MAIN_DBI].md_root); + + return MDB_SUCCESS; +} + +static void +mdb_env_reader_dest(void *ptr) +{ + MDB_reader *reader = ptr; + + reader->mr_txnid = 0; + reader->mr_pid = 0; + reader->mr_tid = 0; +} + +/* downgrade the exclusive lock on the region back to shared */ +static void +mdb_env_share_locks(MDB_env *env) +{ + struct flock lock_info; + + env->me_txns->mti_txnid = env->me_meta->mm_txnid; + if (env->me_metas[0]->mm_txnid < env->me_metas[1]->mm_txnid) + env->me_txns->mti_me_toggle = 1; + + memset((void *)&lock_info, 0, sizeof(lock_info)); + lock_info.l_type = F_RDLCK; + lock_info.l_whence = SEEK_SET; + lock_info.l_start = 0; + lock_info.l_len = 1; + fcntl(env->me_lfd, F_SETLK, &lock_info); +} + +static int +mdb_env_setup_locks(MDB_env *env, char *lpath, int mode, int *excl) +{ + int rc; + off_t size, rsize; + struct flock lock_info; + + *excl = 0; + + if ((env->me_lfd = open(lpath, O_RDWR|O_CREAT, mode)) == -1) { + rc = errno; + return rc; + } + /* Try to get exclusive lock. If we succeed, then + * nobody is using the lock region and we should initialize it. + */ + memset((void *)&lock_info, 0, sizeof(lock_info)); + lock_info.l_type = F_WRLCK; + lock_info.l_whence = SEEK_SET; + lock_info.l_start = 0; + lock_info.l_len = 1; + rc = fcntl(env->me_lfd, F_SETLK, &lock_info); + if (rc == 0) { + *excl = 1; + } else { + lock_info.l_type = F_RDLCK; + rc = fcntl(env->me_lfd, F_SETLK, &lock_info); + if (rc) { + rc = errno; + goto fail; + } + } + size = lseek(env->me_lfd, 0, SEEK_END); + rsize = (env->me_maxreaders-1) * sizeof(MDB_reader) + sizeof(MDB_txninfo); + if (size < rsize && *excl) { + if (ftruncate(env->me_lfd, rsize) != 0) { + rc = errno; + goto fail; + } + } else { + rsize = size; + size = rsize - sizeof(MDB_txninfo); + env->me_maxreaders = size/sizeof(MDB_reader) + 1; + } + env->me_txns = mmap(0, rsize, PROT_READ|PROT_WRITE, MAP_SHARED, + env->me_lfd, 0); + if (env->me_txns == MAP_FAILED) { + rc = errno; + goto fail; + } + if (*excl) { + pthread_mutexattr_t mattr; + + pthread_mutexattr_init(&mattr); + rc = pthread_mutexattr_setpshared(&mattr, PTHREAD_PROCESS_SHARED); + if (rc) { + goto fail; + } + pthread_mutex_init(&env->me_txns->mti_mutex, &mattr); + pthread_mutex_init(&env->me_txns->mti_wmutex, &mattr); + env->me_txns->mti_version = MDB_VERSION; + env->me_txns->mti_magic = MDB_MAGIC; + env->me_txns->mti_txnid = 0; + env->me_txns->mti_numreaders = 0; + env->me_txns->mti_me_toggle = 0; + + } else { + if (env->me_txns->mti_magic != MDB_MAGIC) { + DPUTS("lock region has invalid magic"); + rc = EINVAL; + goto fail; + } + if (env->me_txns->mti_version != MDB_VERSION) { + DPRINTF("lock region is version %u, expected version %u", + env->me_txns->mti_version, MDB_VERSION); + rc = MDB_VERSION_MISMATCH; + goto fail; + } + if (errno != EACCES && errno != EAGAIN) { + rc = errno; + goto fail; + } + } + return MDB_SUCCESS; + +fail: + close(env->me_lfd); + env->me_lfd = -1; + return rc; + +} + +#define LOCKNAME "/lock.mdb" +#define DATANAME "/data.mdb" +int +mdb_env_open(MDB_env *env, const char *path, unsigned int flags, mode_t mode) +{ + int oflags, rc, len, excl; + char *lpath, *dpath; + + len = strlen(path); + lpath = malloc(len + sizeof(LOCKNAME) + len + sizeof(DATANAME)); + if (!lpath) + return ENOMEM; + dpath = lpath + len + sizeof(LOCKNAME); + sprintf(lpath, "%s" LOCKNAME, path); + sprintf(dpath, "%s" DATANAME, path); + + rc = mdb_env_setup_locks(env, lpath, mode, &excl); + if (rc) + goto leave; + + if (F_ISSET(flags, MDB_RDONLY)) + oflags = O_RDONLY; + else + oflags = O_RDWR | O_CREAT; + + if ((env->me_fd = open(dpath, oflags, mode)) == -1) { + rc = errno; + goto leave; + } + + if ((rc = mdb_env_open2(env, flags)) == MDB_SUCCESS) { + /* synchronous fd for meta writes */ + if (!(flags & (MDB_RDONLY|MDB_NOSYNC))) + oflags |= MDB_DSYNC; + if ((env->me_mfd = open(dpath, oflags, mode)) == -1) { + rc = errno; + goto leave; + } + + env->me_path = strdup(path); + DPRINTF("opened dbenv %p", (void *) env); + pthread_key_create(&env->me_txkey, mdb_env_reader_dest); + if (excl) + mdb_env_share_locks(env); + env->me_dbxs = calloc(env->me_maxdbs, sizeof(MDB_dbx)); + env->me_dbs[0] = calloc(env->me_maxdbs, sizeof(MDB_db)); + env->me_dbs[1] = calloc(env->me_maxdbs, sizeof(MDB_db)); + env->me_numdbs = 2; + } + +leave: + if (rc) { + if (env->me_fd >= 0) { + close(env->me_fd); + env->me_fd = -1; + } + if (env->me_lfd >= 0) { + close(env->me_lfd); + env->me_lfd = -1; + } + } + free(lpath); + return rc; +} + +void +mdb_env_close(MDB_env *env) +{ + MDB_dpage *dp; + + if (env == NULL) + return; + + while (env->me_dpages) { + dp = env->me_dpages; + env->me_dpages = (MDB_dpage *)dp->h.md_parent; + free(dp); + } + + free(env->me_dbs[1]); + free(env->me_dbs[0]); + free(env->me_dbxs); + free(env->me_path); + + pthread_key_delete(env->me_txkey); + + if (env->me_map) { + munmap(env->me_map, env->me_mapsize); + } + close(env->me_mfd); + close(env->me_fd); + if (env->me_txns) { + pid_t pid = getpid(); + size_t size = (env->me_maxreaders-1) * sizeof(MDB_reader) + sizeof(MDB_txninfo); + int i; + for (i=0; ime_txns->mti_numreaders; i++) + if (env->me_txns->mti_readers[i].mr_pid == pid) + env->me_txns->mti_readers[i].mr_pid = 0; + munmap(env->me_txns, size); + } + close(env->me_lfd); + free(env); +} + +/* Search for key within a leaf page, using binary search. + * Returns the smallest entry larger or equal to the key. + * If exactp is non-null, stores whether the found entry was an exact match + * in *exactp (1 or 0). + * If kip is non-null, stores the index of the found entry in *kip. + * If no entry larger or equal to the key is found, returns NULL. + */ +static MDB_node * +mdb_search_node(MDB_txn *txn, MDB_dbi dbi, MDB_page *mp, MDB_val *key, + int *exactp, unsigned int *kip) +{ + unsigned int i = 0; + int low, high; + int rc = 0; + MDB_node *node = NULL; + MDB_val nodekey; + DKBUF; + + DPRINTF("searching %u keys in %s page %lu", + NUMKEYS(mp), + IS_LEAF(mp) ? "leaf" : "branch", + mp->mp_pgno); + + assert(NUMKEYS(mp) > 0); + + memset(&nodekey, 0, sizeof(nodekey)); + + low = IS_LEAF(mp) ? 0 : 1; + high = NUMKEYS(mp) - 1; + while (low <= high) { + i = (low + high) >> 1; + + if (IS_LEAF2(mp)) { + nodekey.mv_size = txn->mt_dbs[dbi].md_pad; + nodekey.mv_data = LEAF2KEY(mp, i, nodekey.mv_size); + } else { + node = NODEPTR(mp, i); + + nodekey.mv_size = node->mn_ksize; + nodekey.mv_data = NODEKEY(node); + } + + rc = mdb_cmp(txn, dbi, key, &nodekey); + + if (IS_LEAF(mp)) + DPRINTF("found leaf index %u [%s], rc = %i", + i, DKEY(&nodekey), rc); + else + DPRINTF("found branch index %u [%s -> %lu], rc = %i", + i, DKEY(&nodekey), NODEPGNO(node), rc); + + if (rc == 0) + break; + if (rc > 0) + low = i + 1; + else + high = i - 1; + } + + if (rc > 0) { /* Found entry is less than the key. */ + i++; /* Skip to get the smallest entry larger than key. */ + if (i >= NUMKEYS(mp)) + /* There is no entry larger or equal to the key. */ + return NULL; + } + if (exactp) + *exactp = (rc == 0); + if (kip) /* Store the key index if requested. */ + *kip = i; + + /* nodeptr is fake for LEAF2 */ + return IS_LEAF2(mp) ? NODEPTR(mp, 0) : NODEPTR(mp, i); +} + +static void +cursor_pop_page(MDB_cursor *cursor) +{ + MDB_ppage *top; + + if (cursor->mc_snum) { + top = CURSOR_TOP(cursor); + cursor->mc_snum--; + + DPRINTF("popped page %lu off db %u cursor %p", top->mp_page->mp_pgno, + cursor->mc_dbi, (void *) cursor); + } +} + +static MDB_ppage * +cursor_push_page(MDB_cursor *cursor, MDB_page *mp) +{ + MDB_ppage *ppage; + + DPRINTF("pushing page %lu on db %u cursor %p", mp->mp_pgno, + cursor->mc_dbi, (void *) cursor); + + ppage = &cursor->mc_stack[cursor->mc_snum++]; + ppage->mp_page = mp; + ppage->mp_ki = 0; + return ppage; +} + +static MDB_page * +mdb_get_page(MDB_txn *txn, pgno_t pgno) +{ + MDB_page *p = NULL; + int found = 0; + + if (!F_ISSET(txn->mt_flags, MDB_TXN_RDONLY) && txn->mt_u.dirty_list[0].mid) { + MDB_dpage *dp; + MIDL2 id; + unsigned x; + id.mid = pgno; + x = mdb_midl2_search(txn->mt_u.dirty_list, &id); + if (x <= txn->mt_u.dirty_list[0].mid && txn->mt_u.dirty_list[x].mid == pgno) { + dp = txn->mt_u.dirty_list[x].mptr; + p = &dp->p; + found = 1; + } + } + if (!found) { + if (pgno > txn->mt_env->me_meta->mm_last_pg) + return NULL; + p = (MDB_page *)(txn->mt_env->me_map + txn->mt_env->me_psize * pgno); + } + return p; +} + +static int +mdb_search_page_root(MDB_txn *txn, MDB_dbi dbi, MDB_val *key, + MDB_cursor *cursor, int modify, MDB_pageparent *mpp) +{ + MDB_page *mp = mpp->mp_page; + DKBUF; + int rc; + + if (cursor && cursor_push_page(cursor, mp) == NULL) + return ENOMEM; + + while (IS_BRANCH(mp)) { + unsigned int i = 0; + MDB_node *node; + + DPRINTF("branch page %lu has %u keys", mp->mp_pgno, NUMKEYS(mp)); + assert(NUMKEYS(mp) > 1); + DPRINTF("found index 0 to page %lu", NODEPGNO(NODEPTR(mp, 0))); + + if (key == NULL) /* Initialize cursor to first page. */ + i = 0; + else if (key->mv_size > MAXKEYSIZE && key->mv_data == NULL) { + /* cursor to last page */ + i = NUMKEYS(mp)-1; + } else { + int exact; + node = mdb_search_node(txn, dbi, mp, key, &exact, &i); + if (node == NULL) + i = NUMKEYS(mp) - 1; + else if (!exact) { + assert(i > 0); + i--; + } + } + + if (key) + DPRINTF("following index %u for key [%s]", + i, DKEY(key)); + assert(i < NUMKEYS(mp)); + node = NODEPTR(mp, i); + + if (cursor) + CURSOR_TOP(cursor)->mp_ki = i; + + mpp->mp_parent = mp; + if ((mp = mdb_get_page(txn, NODEPGNO(node))) == NULL) + return MDB_PAGE_NOTFOUND; + mpp->mp_pi = i; + mpp->mp_page = mp; + + if (cursor && cursor_push_page(cursor, mp) == NULL) + return ENOMEM; + + if (modify) { + MDB_dhead *dh = ((MDB_dhead *)mp)-1; + if ((rc = mdb_touch(txn, mpp)) != 0) + return rc; + dh = ((MDB_dhead *)mpp->mp_page)-1; + dh->md_parent = mpp->mp_parent; + dh->md_pi = mpp->mp_pi; + } + + mp = mpp->mp_page; + } + + if (!IS_LEAF(mp)) { + DPRINTF("internal error, index points to a %02X page!?", + mp->mp_flags); + return MDB_CORRUPTED; + } + + DPRINTF("found leaf page %lu for key [%s]", mp->mp_pgno, + key ? DKEY(key) : NULL); + + return MDB_SUCCESS; +} + +/* Search for the page a given key should be in. + * Stores a pointer to the found page in *mpp. + * If key is NULL, search for the lowest page (used by mdb_cursor_first). + * If cursor is non-null, pushes parent pages on the cursor stack. + * If modify is true, visited pages are updated with new page numbers. + */ +static int +mdb_search_page(MDB_txn *txn, MDB_dbi dbi, MDB_val *key, + MDB_cursor *cursor, int modify, MDB_pageparent *mpp) +{ + int rc; + pgno_t root; + + /* Choose which root page to start with. If a transaction is given + * use the root page from the transaction, otherwise read the last + * committed root page. + */ + if (F_ISSET(txn->mt_flags, MDB_TXN_ERROR)) { + DPUTS("transaction has failed, must abort"); + return EINVAL; + } else + root = txn->mt_dbs[dbi].md_root; + + if (root == P_INVALID) { /* Tree is empty. */ + DPUTS("tree is empty"); + return MDB_NOTFOUND; + } + + if ((mpp->mp_page = mdb_get_page(txn, root)) == NULL) + return MDB_PAGE_NOTFOUND; + + DPRINTF("root page has flags 0x%X", mpp->mp_page->mp_flags); + + if (modify) { + /* For sub-databases, update main root first */ + if (dbi > MAIN_DBI && !txn->mt_dbxs[dbi].md_dirty) { + MDB_pageparent mp2; + rc = mdb_search_page(txn, MAIN_DBI, &txn->mt_dbxs[dbi].md_name, + NULL, 1, &mp2); + if (rc) + return rc; + txn->mt_dbxs[dbi].md_dirty = 1; + } + if (!F_ISSET(mpp->mp_page->mp_flags, P_DIRTY)) { + mpp->mp_parent = NULL; + mpp->mp_pi = 0; + if ((rc = mdb_touch(txn, mpp))) + return rc; + txn->mt_dbs[dbi].md_root = mpp->mp_page->mp_pgno; + } + } + + return mdb_search_page_root(txn, dbi, key, cursor, modify, mpp); +} + +static int +mdb_read_data(MDB_txn *txn, MDB_node *leaf, MDB_val *data) +{ + MDB_page *omp; /* overflow mpage */ + pgno_t pgno; + + if (!F_ISSET(leaf->mn_flags, F_BIGDATA)) { + data->mv_size = leaf->mn_dsize; + data->mv_data = NODEDATA(leaf); + return MDB_SUCCESS; + } + + /* Read overflow data. + */ + data->mv_size = leaf->mn_dsize; + memcpy(&pgno, NODEDATA(leaf), sizeof(pgno)); + if ((omp = mdb_get_page(txn, pgno)) == NULL) { + DPRINTF("read overflow page %lu failed", pgno); + return MDB_PAGE_NOTFOUND; + } + data->mv_data = METADATA(omp); + + return MDB_SUCCESS; +} + +int +mdb_get(MDB_txn *txn, MDB_dbi dbi, + MDB_val *key, MDB_val *data) +{ + int rc, exact; + MDB_node *leaf; + MDB_pageparent mpp; + DKBUF; + + assert(key); + assert(data); + DPRINTF("===> get db %u key [%s]", dbi, DKEY(key)); + + if (txn == NULL || !dbi || dbi >= txn->mt_numdbs) + return EINVAL; + + if (key->mv_size == 0 || key->mv_size > MAXKEYSIZE) { + return EINVAL; + } + + if ((rc = mdb_search_page(txn, dbi, key, NULL, 0, &mpp)) != MDB_SUCCESS) + return rc; + + leaf = mdb_search_node(txn, dbi, mpp.mp_page, key, &exact, NULL); + if (leaf && exact) { + /* Return first duplicate data item */ + if (F_ISSET(leaf->mn_flags, F_DUPDATA)) { + MDB_xcursor mx; + + mdb_xcursor_init0(txn, dbi, &mx); + mdb_xcursor_init1(txn, dbi, &mx, leaf); + rc = mdb_search_page(&mx.mx_txn, mx.mx_cursor.mc_dbi, NULL, NULL, 0, &mpp); + if (rc != MDB_SUCCESS) + return rc; + if (IS_LEAF2(mpp.mp_page)) { + data->mv_size = txn->mt_dbs[dbi].md_pad; + data->mv_data = LEAF2KEY(mpp.mp_page, 0, data->mv_size); + } else { + leaf = NODEPTR(mpp.mp_page, 0); + data->mv_size = NODEKSZ(leaf); + data->mv_data = NODEKEY(leaf); + } + } else { + rc = mdb_read_data(txn, leaf, data); + } + } else { + rc = MDB_NOTFOUND; + } + + return rc; +} + +static int +mdb_sibling(MDB_cursor *cursor, int move_right) +{ + int rc; + MDB_node *indx; + MDB_ppage *parent; + MDB_page *mp; + + if (cursor->mc_snum < 2) { + return MDB_NOTFOUND; /* root has no siblings */ + } + parent = CURSOR_PARENT(cursor); + + DPRINTF("parent page is page %lu, index %u", + parent->mp_page->mp_pgno, parent->mp_ki); + + cursor_pop_page(cursor); + if (move_right ? (parent->mp_ki + 1 >= NUMKEYS(parent->mp_page)) + : (parent->mp_ki == 0)) { + DPRINTF("no more keys left, moving to %s sibling", + move_right ? "right" : "left"); + if ((rc = mdb_sibling(cursor, move_right)) != MDB_SUCCESS) + return rc; + parent = CURSOR_TOP(cursor); + } else { + if (move_right) + parent->mp_ki++; + else + parent->mp_ki--; + DPRINTF("just moving to %s index key %u", + move_right ? "right" : "left", parent->mp_ki); + } + assert(IS_BRANCH(parent->mp_page)); + + indx = NODEPTR(parent->mp_page, parent->mp_ki); + if ((mp = mdb_get_page(cursor->mc_txn, NODEPGNO(indx))) == NULL) + return MDB_PAGE_NOTFOUND; +#if 0 + mp->parent = parent->mp_page; + mp->parent_index = parent->mp_ki; +#endif + + cursor_push_page(cursor, mp); + + return MDB_SUCCESS; +} + +static int +mdb_cursor_next(MDB_cursor *cursor, MDB_val *key, MDB_val *data, MDB_cursor_op op) +{ + MDB_ppage *top; + MDB_page *mp; + MDB_node *leaf; + int rc; + + if (cursor->mc_eof) { + return MDB_NOTFOUND; + } + + assert(cursor->mc_initialized); + + top = CURSOR_TOP(cursor); + mp = top->mp_page; + + if (cursor->mc_txn->mt_dbs[cursor->mc_dbi].md_flags & MDB_DUPSORT) { + leaf = NODEPTR(mp, top->mp_ki); + if (F_ISSET(leaf->mn_flags, F_DUPDATA)) { + if (op == MDB_NEXT || op == MDB_NEXT_DUP) { + rc = mdb_cursor_next(&cursor->mc_xcursor->mx_cursor, data, NULL, MDB_NEXT); + if (op != MDB_NEXT || rc == MDB_SUCCESS) + return rc; + } + } else { + cursor->mc_xcursor->mx_cursor.mc_initialized = 0; + if (op == MDB_NEXT_DUP) + return MDB_NOTFOUND; + } + } + + DPRINTF("cursor_next: top page is %lu in cursor %p", mp->mp_pgno, (void *) cursor); + + if (top->mp_ki + 1 >= NUMKEYS(mp)) { + DPUTS("=====> move to next sibling page"); + if (mdb_sibling(cursor, 1) != MDB_SUCCESS) { + cursor->mc_eof = 1; + return MDB_NOTFOUND; + } + top = CURSOR_TOP(cursor); + mp = top->mp_page; + DPRINTF("next page is %lu, key index %u", mp->mp_pgno, top->mp_ki); + } else + top->mp_ki++; + + DPRINTF("==> cursor points to page %lu with %u keys, key index %u", + mp->mp_pgno, NUMKEYS(mp), top->mp_ki); + + if (IS_LEAF2(mp)) { + key->mv_size = cursor->mc_txn->mt_dbs[cursor->mc_dbi].md_pad; + key->mv_data = LEAF2KEY(mp, top->mp_ki, key->mv_size); + return MDB_SUCCESS; + } + + assert(IS_LEAF(mp)); + leaf = NODEPTR(mp, top->mp_ki); + + if (F_ISSET(leaf->mn_flags, F_DUPDATA)) { + mdb_xcursor_init1(cursor->mc_txn, cursor->mc_dbi, cursor->mc_xcursor, leaf); + } + if (data) { + if ((rc = mdb_read_data(cursor->mc_txn, leaf, data) != MDB_SUCCESS)) + return rc; + + if (F_ISSET(leaf->mn_flags, F_DUPDATA)) { + rc = mdb_cursor_first(&cursor->mc_xcursor->mx_cursor, data, NULL); + if (rc != MDB_SUCCESS) + return rc; + } + } + + MDB_SET_KEY(leaf, key); + return MDB_SUCCESS; +} + +static int +mdb_cursor_prev(MDB_cursor *cursor, MDB_val *key, MDB_val *data, MDB_cursor_op op) +{ + MDB_ppage *top; + MDB_page *mp; + MDB_node *leaf; + int rc; + + assert(cursor->mc_initialized); + + top = CURSOR_TOP(cursor); + mp = top->mp_page; + + if (cursor->mc_txn->mt_dbs[cursor->mc_dbi].md_flags & MDB_DUPSORT) { + leaf = NODEPTR(mp, top->mp_ki); + if (op == MDB_PREV || op == MDB_PREV_DUP) { + if (F_ISSET(leaf->mn_flags, F_DUPDATA)) { + rc = mdb_cursor_prev(&cursor->mc_xcursor->mx_cursor, data, NULL, MDB_PREV); + if (op != MDB_PREV || rc == MDB_SUCCESS) + return rc; + } else { + cursor->mc_xcursor->mx_cursor.mc_initialized = 0; + if (op == MDB_PREV_DUP) + return MDB_NOTFOUND; + } + } + } + + DPRINTF("cursor_prev: top page is %lu in cursor %p", mp->mp_pgno, (void *) cursor); + + if (top->mp_ki == 0) { + DPUTS("=====> move to prev sibling page"); + if (mdb_sibling(cursor, 0) != MDB_SUCCESS) { + cursor->mc_initialized = 0; + return MDB_NOTFOUND; + } + top = CURSOR_TOP(cursor); + mp = top->mp_page; + top->mp_ki = NUMKEYS(mp) - 1; + DPRINTF("prev page is %lu, key index %u", mp->mp_pgno, top->mp_ki); + } else + top->mp_ki--; + + cursor->mc_eof = 0; + + DPRINTF("==> cursor points to page %lu with %u keys, key index %u", + mp->mp_pgno, NUMKEYS(mp), top->mp_ki); + + if (IS_LEAF2(mp)) { + key->mv_size = cursor->mc_txn->mt_dbs[cursor->mc_dbi].md_pad; + key->mv_data = LEAF2KEY(mp, top->mp_ki, key->mv_size); + return MDB_SUCCESS; + } + + assert(IS_LEAF(mp)); + leaf = NODEPTR(mp, top->mp_ki); + + if (F_ISSET(leaf->mn_flags, F_DUPDATA)) { + mdb_xcursor_init1(cursor->mc_txn, cursor->mc_dbi, cursor->mc_xcursor, leaf); + } + if (data) { + if ((rc = mdb_read_data(cursor->mc_txn, leaf, data) != MDB_SUCCESS)) + return rc; + + if (F_ISSET(leaf->mn_flags, F_DUPDATA)) { + rc = mdb_cursor_last(&cursor->mc_xcursor->mx_cursor, data, NULL); + if (rc != MDB_SUCCESS) + return rc; + } + } + + MDB_SET_KEY(leaf, key); + return MDB_SUCCESS; +} + +static int +mdb_cursor_set(MDB_cursor *cursor, MDB_val *key, MDB_val *data, + MDB_cursor_op op, int *exactp) +{ + int rc; + MDB_node *leaf; + MDB_ppage *top; + MDB_pageparent mpp; + DKBUF; + + assert(cursor); + assert(key); + assert(key->mv_size > 0); + + /* See if we're already on the right page */ + if (cursor->mc_initialized) { + MDB_val nodekey; + top = CURSOR_TOP(cursor); + /* Don't try this for LEAF2 pages. Maybe support that later. */ + if ((top->mp_page->mp_flags & (P_LEAF|P_LEAF2)) == P_LEAF) { + leaf = NODEPTR(top->mp_page, 0); + MDB_SET_KEY(leaf, &nodekey); + rc = mdb_cmp(cursor->mc_txn, cursor->mc_dbi, key, &nodekey); + if (rc >= 0) { + leaf = NODEPTR(top->mp_page, NUMKEYS(top->mp_page)-1); + MDB_SET_KEY(leaf, &nodekey); + rc = mdb_cmp(cursor->mc_txn, cursor->mc_dbi, key, &nodekey); + if (rc <= 0) { + /* we're already on the right page */ + mpp.mp_page = top->mp_page; + rc = 0; + goto set2; + } + } + } + } + cursor->mc_snum = 0; + + rc = mdb_search_page(cursor->mc_txn, cursor->mc_dbi, key, cursor, 0, &mpp); + if (rc != MDB_SUCCESS) + return rc; + + assert(IS_LEAF(mpp.mp_page)); + + top = CURSOR_TOP(cursor); +set2: + leaf = mdb_search_node(cursor->mc_txn, cursor->mc_dbi, mpp.mp_page, key, exactp, &top->mp_ki); + if (exactp != NULL && !*exactp) { + /* MDB_SET specified and not an exact match. */ + return MDB_NOTFOUND; + } + + if (leaf == NULL) { + DPUTS("===> inexact leaf not found, goto sibling"); + if ((rc = mdb_sibling(cursor, 1)) != MDB_SUCCESS) + return rc; /* no entries matched */ + top = CURSOR_TOP(cursor); + top->mp_ki = 0; + mpp.mp_page = top->mp_page; + assert(IS_LEAF(mpp.mp_page)); + leaf = NODEPTR(mpp.mp_page, 0); + } + + cursor->mc_initialized = 1; + cursor->mc_eof = 0; + + if (IS_LEAF2(mpp.mp_page)) { + key->mv_size = cursor->mc_txn->mt_dbs[cursor->mc_dbi].md_pad; + key->mv_data = LEAF2KEY(mpp.mp_page, top->mp_ki, key->mv_size); + return MDB_SUCCESS; + } + + if (F_ISSET(leaf->mn_flags, F_DUPDATA)) { + mdb_xcursor_init1(cursor->mc_txn, cursor->mc_dbi, cursor->mc_xcursor, leaf); + } + if (data) { + if (F_ISSET(leaf->mn_flags, F_DUPDATA)) { + if (op == MDB_SET || op == MDB_SET_RANGE) { + rc = mdb_cursor_first(&cursor->mc_xcursor->mx_cursor, data, NULL); + } else { + int ex2, *ex2p; + if (op == MDB_GET_BOTH) { + ex2p = &ex2; + } else { + ex2p = NULL; + } + rc = mdb_cursor_set(&cursor->mc_xcursor->mx_cursor, data, NULL, MDB_SET_RANGE, ex2p); + if (rc != MDB_SUCCESS) + return rc; + } + } else if (op == MDB_GET_BOTH || op == MDB_GET_BOTH_RANGE) { + MDB_val d2; + if ((rc = mdb_read_data(cursor->mc_txn, leaf, &d2)) != MDB_SUCCESS) + return rc; + rc = mdb_dcmp(cursor->mc_txn, cursor->mc_dbi, data, &d2); + if (rc) { + if (op == MDB_GET_BOTH || rc > 0) + return MDB_NOTFOUND; + } + + } else { + if ((rc = mdb_read_data(cursor->mc_txn, leaf, data)) != MDB_SUCCESS) + return rc; + } + } + + /* The key already matches in all other cases */ + if (op == MDB_SET_RANGE) + MDB_SET_KEY(leaf, key); + DPRINTF("==> cursor placed on key [%s]", DKEY(key)); + + return rc; +} + +static int +mdb_cursor_first(MDB_cursor *cursor, MDB_val *key, MDB_val *data) +{ + int rc; + MDB_pageparent mpp; + MDB_node *leaf; + + cursor->mc_snum = 0; + + rc = mdb_search_page(cursor->mc_txn, cursor->mc_dbi, NULL, cursor, 0, &mpp); + if (rc != MDB_SUCCESS) + return rc; + assert(IS_LEAF(mpp.mp_page)); + + leaf = NODEPTR(mpp.mp_page, 0); + cursor->mc_initialized = 1; + cursor->mc_eof = 0; + + if (IS_LEAF2(mpp.mp_page)) { + key->mv_size = cursor->mc_txn->mt_dbs[cursor->mc_dbi].md_pad; + key->mv_data = LEAF2KEY(mpp.mp_page, 0, key->mv_size); + return MDB_SUCCESS; + } + + if (data) { + if (F_ISSET(leaf->mn_flags, F_DUPDATA)) { + mdb_xcursor_init1(cursor->mc_txn, cursor->mc_dbi, cursor->mc_xcursor, leaf); + rc = mdb_cursor_first(&cursor->mc_xcursor->mx_cursor, data, NULL); + if (rc) + return rc; + } else { + if (cursor->mc_xcursor) + cursor->mc_xcursor->mx_cursor.mc_initialized = 0; + if ((rc = mdb_read_data(cursor->mc_txn, leaf, data)) != MDB_SUCCESS) + return rc; + } + } + MDB_SET_KEY(leaf, key); + return MDB_SUCCESS; +} + +static int +mdb_cursor_last(MDB_cursor *cursor, MDB_val *key, MDB_val *data) +{ + int rc; + MDB_ppage *top; + MDB_pageparent mpp; + MDB_node *leaf; + MDB_val lkey; + + cursor->mc_snum = 0; + + lkey.mv_size = MAXKEYSIZE+1; + lkey.mv_data = NULL; + + rc = mdb_search_page(cursor->mc_txn, cursor->mc_dbi, &lkey, cursor, 0, &mpp); + if (rc != MDB_SUCCESS) + return rc; + assert(IS_LEAF(mpp.mp_page)); + + leaf = NODEPTR(mpp.mp_page, NUMKEYS(mpp.mp_page)-1); + cursor->mc_initialized = 1; + cursor->mc_eof = 0; + + top = CURSOR_TOP(cursor); + top->mp_ki = NUMKEYS(top->mp_page) - 1; + + if (IS_LEAF2(mpp.mp_page)) { + key->mv_size = cursor->mc_txn->mt_dbs[cursor->mc_dbi].md_pad; + key->mv_data = LEAF2KEY(mpp.mp_page, top->mp_ki, key->mv_size); + return MDB_SUCCESS; + } + + if (data) { + if (F_ISSET(leaf->mn_flags, F_DUPDATA)) { + mdb_xcursor_init1(cursor->mc_txn, cursor->mc_dbi, cursor->mc_xcursor, leaf); + rc = mdb_cursor_last(&cursor->mc_xcursor->mx_cursor, data, NULL); + if (rc) + return rc; + } else { + if ((rc = mdb_read_data(cursor->mc_txn, leaf, data)) != MDB_SUCCESS) + return rc; + } + } + + MDB_SET_KEY(leaf, key); + return MDB_SUCCESS; +} + +int +mdb_cursor_get(MDB_cursor *cursor, MDB_val *key, MDB_val *data, + MDB_cursor_op op) +{ + int rc; + int exact = 0; + + assert(cursor); + + switch (op) { + case MDB_GET_BOTH: + case MDB_GET_BOTH_RANGE: + if (data == NULL || cursor->mc_xcursor == NULL) { + rc = EINVAL; + break; + } + /* FALLTHRU */ + case MDB_SET: + case MDB_SET_RANGE: + if (key == NULL || key->mv_size == 0 || key->mv_size > MAXKEYSIZE) { + rc = EINVAL; + } else if (op == MDB_SET_RANGE) + rc = mdb_cursor_set(cursor, key, data, op, NULL); + else + rc = mdb_cursor_set(cursor, key, data, op, &exact); + break; + case MDB_GET_MULTIPLE: + if (data == NULL || + !(cursor->mc_txn->mt_dbs[cursor->mc_dbi].md_flags & MDB_DUPFIXED) || + !cursor->mc_initialized) { + rc = EINVAL; + break; + } + rc = MDB_SUCCESS; + if (!cursor->mc_xcursor->mx_cursor.mc_initialized || cursor->mc_xcursor->mx_cursor.mc_eof) + break; + goto fetchm; + case MDB_NEXT_MULTIPLE: + if (data == NULL || + !(cursor->mc_txn->mt_dbs[cursor->mc_dbi].md_flags & MDB_DUPFIXED)) { + rc = EINVAL; + break; + } + if (!cursor->mc_initialized) + rc = mdb_cursor_first(cursor, key, data); + else + rc = mdb_cursor_next(cursor, key, data, MDB_NEXT_DUP); + if (rc == MDB_SUCCESS) { + if (cursor->mc_xcursor->mx_cursor.mc_initialized) { + MDB_ppage *top; +fetchm: + top = CURSOR_TOP(&cursor->mc_xcursor->mx_cursor); + data->mv_size = NUMKEYS(top->mp_page) * + cursor->mc_xcursor->mx_txn.mt_dbs[cursor->mc_xcursor->mx_cursor.mc_dbi].md_pad; + data->mv_data = METADATA(top->mp_page); + top->mp_ki = NUMKEYS(top->mp_page)-1; + } else { + rc = MDB_NOTFOUND; + } + } + break; + case MDB_NEXT: + case MDB_NEXT_DUP: + case MDB_NEXT_NODUP: + if (!cursor->mc_initialized) + rc = mdb_cursor_first(cursor, key, data); + else + rc = mdb_cursor_next(cursor, key, data, op); + break; + case MDB_PREV: + case MDB_PREV_DUP: + case MDB_PREV_NODUP: + if (!cursor->mc_initialized || cursor->mc_eof) + rc = mdb_cursor_last(cursor, key, data); + else + rc = mdb_cursor_prev(cursor, key, data, op); + break; + case MDB_FIRST: + rc = mdb_cursor_first(cursor, key, data); + break; + case MDB_LAST: + rc = mdb_cursor_last(cursor, key, data); + break; + default: + DPRINTF("unhandled/unimplemented cursor operation %u", op); + rc = EINVAL; + break; + } + + return rc; +} + +/* Allocate a page and initialize it + */ +static MDB_dpage * +mdb_new_page(MDB_txn *txn, MDB_dbi dbi, uint32_t flags, int num) +{ + MDB_dpage *dp; + + if ((dp = mdb_alloc_page(txn, NULL, 0, num)) == NULL) + return NULL; + DPRINTF("allocated new mpage %lu, page size %u", + dp->p.mp_pgno, txn->mt_env->me_psize); + dp->p.mp_flags = flags | P_DIRTY; + dp->p.mp_lower = PAGEHDRSZ; + dp->p.mp_upper = txn->mt_env->me_psize; + + if (IS_BRANCH(&dp->p)) + txn->mt_dbs[dbi].md_branch_pages++; + else if (IS_LEAF(&dp->p)) + txn->mt_dbs[dbi].md_leaf_pages++; + else if (IS_OVERFLOW(&dp->p)) { + txn->mt_dbs[dbi].md_overflow_pages += num; + dp->p.mp_pages = num; + } + + return dp; +} + +static size_t +mdb_leaf_size(MDB_env *env, MDB_val *key, MDB_val *data) +{ + size_t sz; + + sz = LEAFSIZE(key, data); + if (data->mv_size >= env->me_psize / MDB_MINKEYS) { + /* put on overflow page */ + sz -= data->mv_size - sizeof(pgno_t); + } + + return sz + sizeof(indx_t); +} + +static size_t +mdb_branch_size(MDB_env *env, MDB_val *key) +{ + size_t sz; + + sz = INDXSIZE(key); + if (sz >= env->me_psize / MDB_MINKEYS) { + /* put on overflow page */ + /* not implemented */ + /* sz -= key->size - sizeof(pgno_t); */ + } + + return sz + sizeof(indx_t); +} + +static int +mdb_add_node(MDB_txn *txn, MDB_dbi dbi, MDB_page *mp, indx_t indx, + MDB_val *key, MDB_val *data, pgno_t pgno, uint8_t flags) +{ + unsigned int i; + size_t node_size = NODESIZE; + indx_t ofs; + MDB_node *node; + MDB_dpage *ofp = NULL; /* overflow page */ + DKBUF; + + assert(mp->mp_upper >= mp->mp_lower); + + DPRINTF("add node [%s] to %s page %lu at index %i, key size %zu", + key ? DKEY(key) : NULL, + IS_LEAF(mp) ? "leaf" : "branch", + mp->mp_pgno, indx, key ? key->mv_size : 0); + + if (IS_LEAF2(mp)) { + /* Move higher keys up one slot. */ + int ksize = txn->mt_dbs[dbi].md_pad, dif; + char *ptr = LEAF2KEY(mp, indx, ksize); + dif = NUMKEYS(mp) - indx; + if (dif > 0) + memmove(ptr+ksize, ptr, dif*ksize); + /* insert new key */ + memcpy(ptr, key->mv_data, ksize); + + /* Just using these for counting */ + mp->mp_lower += sizeof(indx_t); + mp->mp_upper -= ksize - sizeof(indx_t); + return MDB_SUCCESS; + } + + if (key != NULL) + node_size += key->mv_size; + + if (IS_LEAF(mp)) { + assert(data); + if (F_ISSET(flags, F_BIGDATA)) { + /* Data already on overflow page. */ + node_size += sizeof(pgno_t); + } else if (data->mv_size >= txn->mt_env->me_psize / MDB_MINKEYS) { + int ovpages = OVPAGES(data->mv_size, txn->mt_env->me_psize); + /* Put data on overflow page. */ + DPRINTF("data size is %zu, put on overflow page", + data->mv_size); + node_size += sizeof(pgno_t); + if ((ofp = mdb_new_page(txn, dbi, P_OVERFLOW, ovpages)) == NULL) + return ENOMEM; + DPRINTF("allocated overflow page %lu", ofp->p.mp_pgno); + flags |= F_BIGDATA; + } else { + node_size += data->mv_size; + } + } + + if (node_size + sizeof(indx_t) > SIZELEFT(mp)) { + DPRINTF("not enough room in page %lu, got %u ptrs", + mp->mp_pgno, NUMKEYS(mp)); + DPRINTF("upper - lower = %u - %u = %u", mp->mp_upper, mp->mp_lower, + mp->mp_upper - mp->mp_lower); + DPRINTF("node size = %zu", node_size); + return ENOSPC; + } + + /* Move higher pointers up one slot. */ + for (i = NUMKEYS(mp); i > indx; i--) + mp->mp_ptrs[i] = mp->mp_ptrs[i - 1]; + + /* Adjust free space offsets. */ + ofs = mp->mp_upper - node_size; + assert(ofs >= mp->mp_lower + sizeof(indx_t)); + mp->mp_ptrs[indx] = ofs; + mp->mp_upper = ofs; + mp->mp_lower += sizeof(indx_t); + + /* Write the node data. */ + node = NODEPTR(mp, indx); + node->mn_ksize = (key == NULL) ? 0 : key->mv_size; + node->mn_flags = flags; + if (IS_LEAF(mp)) + node->mn_dsize = data->mv_size; + else + NODEPGNO(node) = pgno; + + if (key) + memcpy(NODEKEY(node), key->mv_data, key->mv_size); + + if (IS_LEAF(mp)) { + assert(key); + if (ofp == NULL) { + if (F_ISSET(flags, F_BIGDATA)) + memcpy(node->mn_data + key->mv_size, data->mv_data, + sizeof(pgno_t)); + else + memcpy(node->mn_data + key->mv_size, data->mv_data, + data->mv_size); + } else { + memcpy(node->mn_data + key->mv_size, &ofp->p.mp_pgno, + sizeof(pgno_t)); + memcpy(METADATA(&ofp->p), data->mv_data, data->mv_size); + } + } + + return MDB_SUCCESS; +} + +static void +mdb_del_node(MDB_page *mp, indx_t indx, int ksize) +{ + unsigned int sz; + indx_t i, j, numkeys, ptr; + MDB_node *node; + char *base; + + DPRINTF("delete node %u on %s page %lu", indx, + IS_LEAF(mp) ? "leaf" : "branch", mp->mp_pgno); + assert(indx < NUMKEYS(mp)); + + if (IS_LEAF2(mp)) { + int x = NUMKEYS(mp) - 1 - indx; + base = LEAF2KEY(mp, indx, ksize); + if (x) + memmove(base, base + ksize, x * ksize); + mp->mp_lower -= sizeof(indx_t); + mp->mp_upper += ksize - sizeof(indx_t); + return; + } + + node = NODEPTR(mp, indx); + sz = NODESIZE + node->mn_ksize; + if (IS_LEAF(mp)) { + if (F_ISSET(node->mn_flags, F_BIGDATA)) + sz += sizeof(pgno_t); + else + sz += NODEDSZ(node); + } + + ptr = mp->mp_ptrs[indx]; + numkeys = NUMKEYS(mp); + for (i = j = 0; i < numkeys; i++) { + if (i != indx) { + mp->mp_ptrs[j] = mp->mp_ptrs[i]; + if (mp->mp_ptrs[i] < ptr) + mp->mp_ptrs[j] += sz; + j++; + } + } + + base = (char *)mp + mp->mp_upper; + memmove(base + sz, base, ptr - mp->mp_upper); + + mp->mp_lower -= sizeof(indx_t); + mp->mp_upper += sz; +} + +static void +mdb_xcursor_init0(MDB_txn *txn, MDB_dbi dbi, MDB_xcursor *mx) +{ + MDB_dbi dbn; + + mx->mx_txn = *txn; + mx->mx_txn.mt_dbxs = mx->mx_dbxs; + mx->mx_txn.mt_dbs = mx->mx_dbs; + mx->mx_dbxs[0] = txn->mt_dbxs[0]; + mx->mx_dbxs[1] = txn->mt_dbxs[1]; + if (dbi > 1) { + mx->mx_dbxs[2] = txn->mt_dbxs[dbi]; + dbn = 2; + } else { + dbn = 1; + } + mx->mx_dbxs[dbn+1].md_parent = dbn; + mx->mx_dbxs[dbn+1].md_cmp = mx->mx_dbxs[dbn].md_dcmp; + mx->mx_dbxs[dbn+1].md_rel = mx->mx_dbxs[dbn].md_rel; + mx->mx_dbxs[dbn+1].md_dirty = 0; + mx->mx_txn.mt_numdbs = dbn+2; + + mx->mx_cursor.mc_snum = 0; + mx->mx_cursor.mc_txn = &mx->mx_txn; + mx->mx_cursor.mc_dbi = dbn+1; +} + +static void +mdb_xcursor_init1(MDB_txn *txn, MDB_dbi dbi, MDB_xcursor *mx, MDB_node *node) +{ + MDB_db *db = NODEDATA(node); + MDB_dbi dbn; + mx->mx_dbs[0] = txn->mt_dbs[0]; + mx->mx_dbs[1] = txn->mt_dbs[1]; + if (dbi > 1) { + mx->mx_dbs[2] = txn->mt_dbs[dbi]; + dbn = 3; + } else { + dbn = 2; + } + mx->mx_dbs[dbn] = *db; + mx->mx_dbxs[dbn].md_name.mv_data = NODEKEY(node); + mx->mx_dbxs[dbn].md_name.mv_size = node->mn_ksize; + mx->mx_txn.mt_next_pgno = txn->mt_next_pgno; + mx->mx_txn.mt_oldest = txn->mt_oldest; + mx->mx_txn.mt_u = txn->mt_u; + mx->mx_cursor.mc_initialized = 0; + mx->mx_cursor.mc_eof = 0; +} + +static void +mdb_xcursor_fini(MDB_txn *txn, MDB_dbi dbi, MDB_xcursor *mx) +{ + txn->mt_next_pgno = mx->mx_txn.mt_next_pgno; + txn->mt_oldest = mx->mx_txn.mt_oldest; + txn->mt_u = mx->mx_txn.mt_u; + txn->mt_dbs[0] = mx->mx_dbs[0]; + txn->mt_dbs[1] = mx->mx_dbs[1]; + txn->mt_dbxs[0].md_dirty = mx->mx_dbxs[0].md_dirty; + txn->mt_dbxs[1].md_dirty = mx->mx_dbxs[1].md_dirty; + if (dbi > 1) { + txn->mt_dbs[dbi] = mx->mx_dbs[2]; + txn->mt_dbxs[dbi].md_dirty = mx->mx_dbxs[2].md_dirty; + } +} + +int +mdb_cursor_open(MDB_txn *txn, MDB_dbi dbi, MDB_cursor **ret) +{ + MDB_cursor *cursor; + size_t size = sizeof(MDB_cursor); + + if (txn == NULL || ret == NULL || !dbi || dbi >= txn->mt_numdbs) + return EINVAL; + + if (txn->mt_dbs[dbi].md_flags & MDB_DUPSORT) + size += sizeof(MDB_xcursor); + + if ((cursor = calloc(1, size)) != NULL) { + cursor->mc_dbi = dbi; + cursor->mc_txn = txn; + if (txn->mt_dbs[dbi].md_flags & MDB_DUPSORT) { + MDB_xcursor *mx = (MDB_xcursor *)(cursor + 1); + cursor->mc_xcursor = mx; + mdb_xcursor_init0(txn, dbi, mx); + } + } else { + return ENOMEM; + } + + *ret = cursor; + + return MDB_SUCCESS; +} + +/* Return the count of duplicate data items for the current key */ +int +mdb_cursor_count(MDB_cursor *mc, unsigned long *countp) +{ + MDB_ppage *top; + MDB_node *leaf; + + if (mc == NULL || countp == NULL) + return EINVAL; + + if (!(mc->mc_txn->mt_dbs[mc->mc_dbi].md_flags & MDB_DUPSORT)) + return EINVAL; + + top = CURSOR_TOP(mc); + leaf = NODEPTR(top->mp_page, top->mp_ki); + if (!F_ISSET(leaf->mn_flags, F_DUPDATA)) { + *countp = 1; + } else { + if (!mc->mc_xcursor->mx_cursor.mc_initialized) + return EINVAL; + + *countp = mc->mc_xcursor->mx_txn.mt_dbs[mc->mc_xcursor->mx_cursor.mc_dbi].md_entries; + } + return MDB_SUCCESS; +} + +void +mdb_cursor_close(MDB_cursor *cursor) +{ + if (cursor != NULL) { + free(cursor); + } +} + +static int +mdb_update_key(MDB_page *mp, indx_t indx, MDB_val *key) +{ + indx_t ptr, i, numkeys; + int delta; + size_t len; + MDB_node *node; + char *base; + DKBUF; + + node = NODEPTR(mp, indx); + ptr = mp->mp_ptrs[indx]; + DPRINTF("update key %u (ofs %u) [%.*s] to [%s] on page %lu", + indx, ptr, + (int)node->mn_ksize, (char *)NODEKEY(node), + DKEY(key), + mp->mp_pgno); + + delta = key->mv_size - node->mn_ksize; + if (delta) { + if (delta > 0 && SIZELEFT(mp) < delta) { + DPRINTF("OUCH! Not enough room, delta = %d", delta); + return ENOSPC; + } + + numkeys = NUMKEYS(mp); + for (i = 0; i < numkeys; i++) { + if (mp->mp_ptrs[i] <= ptr) + mp->mp_ptrs[i] -= delta; + } + + base = (char *)mp + mp->mp_upper; + len = ptr - mp->mp_upper + NODESIZE; + memmove(base - delta, base, len); + mp->mp_upper -= delta; + + node = NODEPTR(mp, indx); + node->mn_ksize = key->mv_size; + } + + memcpy(NODEKEY(node), key->mv_data, key->mv_size); + + return MDB_SUCCESS; +} + +/* Move a node from src to dst. + */ +static int +mdb_move_node(MDB_txn *txn, MDB_dbi dbi, MDB_pageparent *src, indx_t srcindx, + MDB_pageparent *dst, indx_t dstindx) +{ + int rc; + MDB_node *srcnode; + MDB_val key, data; + DKBUF; + + /* Mark src and dst as dirty. */ + if ((rc = mdb_touch(txn, src)) || + (rc = mdb_touch(txn, dst))) + return rc;; + + if (IS_LEAF2(src->mp_page)) { + srcnode = NODEPTR(src->mp_page, 0); /* fake */ + key.mv_size = txn->mt_dbs[dbi].md_pad; + key.mv_data = LEAF2KEY(src->mp_page, srcindx, key.mv_size); + data.mv_size = 0; + data.mv_data = NULL; + } else { + srcnode = NODEPTR(src->mp_page, srcindx); + key.mv_size = NODEKSZ(srcnode); + key.mv_data = NODEKEY(srcnode); + data.mv_size = NODEDSZ(srcnode); + data.mv_data = NODEDATA(srcnode); + } + DPRINTF("moving %s node %u [%s] on page %lu to node %u on page %lu", + IS_LEAF(src->mp_page) ? "leaf" : "branch", + srcindx, + DKEY(&key), + src->mp_page->mp_pgno, + dstindx, dst->mp_page->mp_pgno); + + /* Add the node to the destination page. + */ + rc = mdb_add_node(txn, dbi, dst->mp_page, dstindx, &key, &data, NODEPGNO(srcnode), + srcnode->mn_flags); + if (rc != MDB_SUCCESS) + return rc; + + /* Delete the node from the source page. + */ + mdb_del_node(src->mp_page, srcindx, key.mv_size); + + /* The key value just changed due to del_node, find it again. + */ + if (!IS_LEAF2(src->mp_page)) { + srcnode = NODEPTR(src->mp_page, srcindx); + key.mv_data = NODEKEY(srcnode); + } + + /* Update the parent separators. + */ + if (srcindx == 0) { + if (src->mp_pi != 0) { + DPRINTF("update separator for source page %lu to [%s]", + src->mp_page->mp_pgno, DKEY(&key)); + if ((rc = mdb_update_key(src->mp_parent, src->mp_pi, + &key)) != MDB_SUCCESS) + return rc; + } + if (IS_BRANCH(src->mp_page)) { + MDB_val nullkey; + nullkey.mv_size = 0; + assert(mdb_update_key(src->mp_page, 0, &nullkey) == MDB_SUCCESS); + } + } + + if (dstindx == 0) { + if (dst->mp_pi != 0) { + DPRINTF("update separator for destination page %lu to [%s]", + dst->mp_page->mp_pgno, DKEY(&key)); + if ((rc = mdb_update_key(dst->mp_parent, dst->mp_pi, + &key)) != MDB_SUCCESS) + return rc; + } + if (IS_BRANCH(dst->mp_page)) { + MDB_val nullkey; + nullkey.mv_size = 0; + assert(mdb_update_key(dst->mp_page, 0, &nullkey) == MDB_SUCCESS); + } + } + + return MDB_SUCCESS; +} + +static int +mdb_merge(MDB_txn *txn, MDB_dbi dbi, MDB_pageparent *src, MDB_pageparent *dst) +{ + int rc; + indx_t i; + MDB_node *srcnode; + MDB_val key, data; + MDB_pageparent mpp; + MDB_dhead *dh; + + DPRINTF("merging page %lu and %lu", src->mp_page->mp_pgno, dst->mp_page->mp_pgno); + + assert(txn != NULL); + assert(src->mp_parent); /* can't merge root page */ + assert(dst->mp_parent); + + /* Mark src and dst as dirty. */ + if ((rc = mdb_touch(txn, src)) || + (rc = mdb_touch(txn, dst))) + return rc; + + /* Move all nodes from src to dst. + */ + if (IS_LEAF2(src->mp_page)) { + key.mv_size = txn->mt_dbs[dbi].md_pad; + key.mv_data = METADATA(src->mp_page); + for (i = 0; i < NUMKEYS(src->mp_page); i++) { + rc = mdb_add_node(txn, dbi, dst->mp_page, NUMKEYS(dst->mp_page), &key, + NULL, 0, 0); + if (rc != MDB_SUCCESS) + return rc; + key.mv_data = (char *)key.mv_data + key.mv_size; + } + } else { + for (i = 0; i < NUMKEYS(src->mp_page); i++) { + srcnode = NODEPTR(src->mp_page, i); + + key.mv_size = srcnode->mn_ksize; + key.mv_data = NODEKEY(srcnode); + data.mv_size = NODEDSZ(srcnode); + data.mv_data = NODEDATA(srcnode); + rc = mdb_add_node(txn, dbi, dst->mp_page, NUMKEYS(dst->mp_page), &key, + &data, NODEPGNO(srcnode), srcnode->mn_flags); + if (rc != MDB_SUCCESS) + return rc; + } + } + + DPRINTF("dst page %lu now has %u keys (%.1f%% filled)", + dst->mp_page->mp_pgno, NUMKEYS(dst->mp_page), (float)PAGEFILL(txn->mt_env, dst->mp_page) / 10); + + /* Unlink the src page from parent. + */ + mdb_del_node(src->mp_parent, src->mp_pi, 0); + if (src->mp_pi == 0) { + key.mv_size = 0; + if ((rc = mdb_update_key(src->mp_parent, 0, &key)) != MDB_SUCCESS) + return rc; + } + + if (IS_LEAF(src->mp_page)) + txn->mt_dbs[dbi].md_leaf_pages--; + else + txn->mt_dbs[dbi].md_branch_pages--; + + mpp.mp_page = src->mp_parent; + dh = (MDB_dhead *)src->mp_parent; + dh--; + mpp.mp_parent = dh->md_parent; + mpp.mp_pi = dh->md_pi; + + return mdb_rebalance(txn, dbi, &mpp); +} + +#define FILL_THRESHOLD 250 + +static int +mdb_rebalance(MDB_txn *txn, MDB_dbi dbi, MDB_pageparent *mpp) +{ + MDB_node *node; + MDB_page *root; + MDB_pageparent npp; + indx_t si = 0, di = 0; + + assert(txn != NULL); + assert(mpp != NULL); + + DPRINTF("rebalancing %s page %lu (has %u keys, %.1f%% full)", + IS_LEAF(mpp->mp_page) ? "leaf" : "branch", + mpp->mp_page->mp_pgno, NUMKEYS(mpp->mp_page), (float)PAGEFILL(txn->mt_env, mpp->mp_page) / 10); + + if (PAGEFILL(txn->mt_env, mpp->mp_page) >= FILL_THRESHOLD) { + DPRINTF("no need to rebalance page %lu, above fill threshold", + mpp->mp_page->mp_pgno); + return MDB_SUCCESS; + } + + if (mpp->mp_parent == NULL) { + if (NUMKEYS(mpp->mp_page) == 0) { + DPUTS("tree is completely empty"); + txn->mt_dbs[dbi].md_root = P_INVALID; + txn->mt_dbs[dbi].md_depth = 0; + txn->mt_dbs[dbi].md_leaf_pages = 0; + } else if (IS_BRANCH(mpp->mp_page) && NUMKEYS(mpp->mp_page) == 1) { + DPUTS("collapsing root page!"); + txn->mt_dbs[dbi].md_root = NODEPGNO(NODEPTR(mpp->mp_page, 0)); + if ((root = mdb_get_page(txn, txn->mt_dbs[dbi].md_root)) == NULL) + return MDB_PAGE_NOTFOUND; + txn->mt_dbs[dbi].md_depth--; + txn->mt_dbs[dbi].md_branch_pages--; + } else + DPUTS("root page doesn't need rebalancing"); + return MDB_SUCCESS; + } + + /* The parent (branch page) must have at least 2 pointers, + * otherwise the tree is invalid. + */ + assert(NUMKEYS(mpp->mp_parent) > 1); + + /* Leaf page fill factor is below the threshold. + * Try to move keys from left or right neighbor, or + * merge with a neighbor page. + */ + + /* Find neighbors. + */ + if (mpp->mp_pi == 0) { + /* We're the leftmost leaf in our parent. + */ + DPUTS("reading right neighbor"); + node = NODEPTR(mpp->mp_parent, mpp->mp_pi + 1); + if ((npp.mp_page = mdb_get_page(txn, NODEPGNO(node))) == NULL) + return MDB_PAGE_NOTFOUND; + npp.mp_pi = mpp->mp_pi + 1; + si = 0; + di = NUMKEYS(mpp->mp_page); + } else { + /* There is at least one neighbor to the left. + */ + DPUTS("reading left neighbor"); + node = NODEPTR(mpp->mp_parent, mpp->mp_pi - 1); + if ((npp.mp_page = mdb_get_page(txn, NODEPGNO(node))) == NULL) + return MDB_PAGE_NOTFOUND; + npp.mp_pi = mpp->mp_pi - 1; + si = NUMKEYS(npp.mp_page) - 1; + di = 0; + } + npp.mp_parent = mpp->mp_parent; + + DPRINTF("found neighbor page %lu (%u keys, %.1f%% full)", + npp.mp_page->mp_pgno, NUMKEYS(npp.mp_page), (float)PAGEFILL(txn->mt_env, npp.mp_page) / 10); + + /* If the neighbor page is above threshold and has at least two + * keys, move one key from it. + * + * Otherwise we should try to merge them. + */ + if (PAGEFILL(txn->mt_env, npp.mp_page) >= FILL_THRESHOLD && NUMKEYS(npp.mp_page) >= 2) + return mdb_move_node(txn, dbi, &npp, si, mpp, di); + else { /* FIXME: if (has_enough_room()) */ + if (mpp->mp_pi == 0) + return mdb_merge(txn, dbi, &npp, mpp); + else + return mdb_merge(txn, dbi, mpp, &npp); + } +} + +static int +mdb_del0(MDB_txn *txn, MDB_dbi dbi, unsigned int ki, MDB_pageparent *mpp, MDB_node *leaf) +{ + int rc; + + /* add overflow pages to free list */ + if (!IS_LEAF2(mpp->mp_page) && F_ISSET(leaf->mn_flags, F_BIGDATA)) { + int i, ovpages; + pgno_t pg; + + memcpy(&pg, NODEDATA(leaf), sizeof(pg)); + ovpages = OVPAGES(NODEDSZ(leaf), txn->mt_env->me_psize); + for (i=0; imt_free_pgs, pg); + pg++; + } + } + mdb_del_node(mpp->mp_page, ki, txn->mt_dbs[dbi].md_pad); + txn->mt_dbs[dbi].md_entries--; + rc = mdb_rebalance(txn, dbi, mpp); + if (rc != MDB_SUCCESS) + txn->mt_flags |= MDB_TXN_ERROR; + + return rc; +} + +int +mdb_del(MDB_txn *txn, MDB_dbi dbi, + MDB_val *key, MDB_val *data, + unsigned int flags) +{ + int rc, exact; + unsigned int ki; + MDB_node *leaf; + MDB_pageparent mpp; + DKBUF; + + assert(key != NULL); + + DPRINTF("====> delete db %u key [%s]", dbi, DKEY(key)); + + if (txn == NULL || !dbi || dbi >= txn->mt_numdbs) + return EINVAL; + + if (F_ISSET(txn->mt_flags, MDB_TXN_RDONLY)) { + return EINVAL; + } + + if (key->mv_size == 0 || key->mv_size > MAXKEYSIZE) { + return EINVAL; + } + + mpp.mp_parent = NULL; + mpp.mp_pi = 0; + if ((rc = mdb_search_page(txn, dbi, key, NULL, 1, &mpp)) != MDB_SUCCESS) + return rc; + + leaf = mdb_search_node(txn, dbi, mpp.mp_page, key, &exact, &ki); + if (leaf == NULL || !exact) { + return MDB_NOTFOUND; + } + + if (!IS_LEAF2(mpp.mp_page) && F_ISSET(leaf->mn_flags, F_DUPDATA)) { + MDB_xcursor mx; + MDB_pageparent mp2; + + mdb_xcursor_init0(txn, dbi, &mx); + mdb_xcursor_init1(txn, dbi, &mx, leaf); + if (flags == MDB_DEL_DUP) { + rc = mdb_del(&mx.mx_txn, mx.mx_cursor.mc_dbi, data, NULL, 0); + mdb_xcursor_fini(txn, dbi, &mx); + if (rc != MDB_SUCCESS) + return rc; + /* If sub-DB still has entries, we're done */ + if (mx.mx_txn.mt_dbs[mx.mx_cursor.mc_dbi].md_root != P_INVALID) { + memcpy(NODEDATA(leaf), &mx.mx_txn.mt_dbs[mx.mx_cursor.mc_dbi], + sizeof(MDB_db)); + txn->mt_dbs[dbi].md_entries--; + return rc; + } + /* otherwise fall thru and delete the sub-DB */ + } else { + /* add all the child DB's pages to the free list */ + rc = mdb_search_page(&mx.mx_txn, mx.mx_cursor.mc_dbi, + NULL, &mx.mx_cursor, 0, &mp2); + if (rc == MDB_SUCCESS) { + MDB_ppage *top, *parent; + MDB_node *ni; + unsigned int i; + + cursor_pop_page(&mx.mx_cursor); + if (mx.mx_cursor.mc_snum) { + top = CURSOR_TOP(&mx.mx_cursor); + while (mx.mx_cursor.mc_snum > 1) { + parent = CURSOR_PARENT(&mx.mx_cursor); + for (i=0; imp_page); i++) { + ni = NODEPTR(top->mp_page, i); + mdb_midl_insert(txn->mt_free_pgs, NODEPGNO(ni)); + } + parent->mp_ki++; + if (parent->mp_ki >= NUMKEYS(parent->mp_page)) { + cursor_pop_page(&mx.mx_cursor); + top = parent; + } else { + ni = NODEPTR(parent->mp_page, parent->mp_ki); + top->mp_page = mdb_get_page(&mx.mx_txn, NODEPGNO(ni)); + } + } + } + mdb_midl_insert(txn->mt_free_pgs, mx.mx_txn.mt_dbs[mx.mx_cursor.mc_dbi].md_root); + } + } + } + + if (data && (rc = mdb_read_data(txn, leaf, data)) != MDB_SUCCESS) + return rc; + + return mdb_del0(txn, dbi, ki, &mpp, leaf); +} + +/* Split page <*mpp>, and insert in either left or + * right sibling, at index <*newindxp> (as if unsplit). Updates *mpp and + * *newindxp with the actual values after split, ie if *mpp and *newindxp + * refer to a node in the new right sibling page. + */ +static int +mdb_split(MDB_txn *txn, MDB_dbi dbi, MDB_page **mpp, unsigned int *newindxp, + MDB_val *newkey, MDB_val *newdata, pgno_t newpgno) +{ + uint8_t flags; + int rc = MDB_SUCCESS, ins_new = 0; + indx_t newindx; + pgno_t pgno = 0; + unsigned int i, j, split_indx; + MDB_node *node; + MDB_val sepkey, rkey, rdata; + MDB_page *copy; + MDB_dpage *mdp, *rdp, *pdp; + MDB_dhead *dh; + DKBUF; + + assert(txn != NULL); + + dh = ((MDB_dhead *)*mpp) - 1; + mdp = (MDB_dpage *)dh; + newindx = *newindxp; + + DPRINTF("-----> splitting %s page %lu and adding [%s] at index %i", + IS_LEAF(&mdp->p) ? "leaf" : "branch", mdp->p.mp_pgno, + DKEY(newkey), *newindxp); + + if (mdp->h.md_parent == NULL) { + if ((pdp = mdb_new_page(txn, dbi, P_BRANCH, 1)) == NULL) + return ENOMEM; + mdp->h.md_pi = 0; + mdp->h.md_parent = &pdp->p; + txn->mt_dbs[dbi].md_root = pdp->p.mp_pgno; + DPRINTF("root split! new root = %lu", pdp->p.mp_pgno); + txn->mt_dbs[dbi].md_depth++; + + /* Add left (implicit) pointer. */ + if ((rc = mdb_add_node(txn, dbi, &pdp->p, 0, NULL, NULL, + mdp->p.mp_pgno, 0)) != MDB_SUCCESS) + return rc; + } else { + DPRINTF("parent branch page is %lu", mdp->h.md_parent->mp_pgno); + } + + /* Create a right sibling. */ + if ((rdp = mdb_new_page(txn, dbi, mdp->p.mp_flags, 1)) == NULL) + return ENOMEM; + rdp->h.md_parent = mdp->h.md_parent; + rdp->h.md_pi = mdp->h.md_pi + 1; + DPRINTF("new right sibling: page %lu", rdp->p.mp_pgno); + + split_indx = NUMKEYS(&mdp->p) / 2 + 1; + + if (IS_LEAF2(&rdp->p)) { + char *split, *ins; + int x; + unsigned int nkeys = NUMKEYS(&mdp->p), lsize, rsize, ksize; + /* Move half of the keys to the right sibling */ + copy = NULL; + x = *newindxp - split_indx; + ksize = txn->mt_dbs[dbi].md_pad; + split = LEAF2KEY(&mdp->p, split_indx, ksize); + rsize = (nkeys - split_indx) * ksize; + lsize = (nkeys - split_indx) * sizeof(indx_t); + mdp->p.mp_lower -= lsize; + rdp->p.mp_lower += lsize; + mdp->p.mp_upper += rsize - lsize; + rdp->p.mp_upper -= rsize - lsize; + sepkey.mv_size = ksize; + if (newindx == split_indx) { + sepkey.mv_data = newkey->mv_data; + } else { + sepkey.mv_data = split; + } + if (x<0) { + ins = LEAF2KEY(&mdp->p, *newindxp, ksize); + memcpy(&rdp->p.mp_ptrs, split, rsize); + sepkey.mv_data = &rdp->p.mp_ptrs; + memmove(ins+ksize, ins, (split_indx - *newindxp) * ksize); + memcpy(ins, newkey->mv_data, ksize); + mdp->p.mp_lower += sizeof(indx_t); + mdp->p.mp_upper -= ksize - sizeof(indx_t); + } else { + if (x) + memcpy(&rdp->p.mp_ptrs, split, x * ksize); + ins = LEAF2KEY(&rdp->p, x, ksize); + memcpy(ins, newkey->mv_data, ksize); + memcpy(ins+ksize, split + x * ksize, rsize - x * ksize); + rdp->p.mp_lower += sizeof(indx_t); + rdp->p.mp_upper -= ksize - sizeof(indx_t); + *newindxp = x; + *mpp = &rdp->p; + } + goto newsep; + } + + /* Move half of the keys to the right sibling. */ + if ((copy = malloc(txn->mt_env->me_psize)) == NULL) + return ENOMEM; + memcpy(copy, &mdp->p, txn->mt_env->me_psize); + memset(&mdp->p.mp_ptrs, 0, txn->mt_env->me_psize - PAGEHDRSZ); + mdp->p.mp_lower = PAGEHDRSZ; + mdp->p.mp_upper = txn->mt_env->me_psize; + + /* First find the separating key between the split pages. + */ + memset(&sepkey, 0, sizeof(sepkey)); + if (newindx == split_indx) { + sepkey.mv_size = newkey->mv_size; + sepkey.mv_data = newkey->mv_data; + } else { + node = NODEPTR(copy, split_indx); + sepkey.mv_size = node->mn_ksize; + sepkey.mv_data = NODEKEY(node); + } + +newsep: + DPRINTF("separator is [%s]", DKEY(&sepkey)); + + /* Copy separator key to the parent. + */ + if (SIZELEFT(rdp->h.md_parent) < mdb_branch_size(txn->mt_env, &sepkey)) { + rc = mdb_split(txn, dbi, &rdp->h.md_parent, &rdp->h.md_pi, + &sepkey, NULL, rdp->p.mp_pgno); + + /* Right page might now have changed parent. + * Check if left page also changed parent. + */ + if (rdp->h.md_parent != mdp->h.md_parent && + mdp->h.md_pi >= NUMKEYS(mdp->h.md_parent)) { + mdp->h.md_parent = rdp->h.md_parent; + mdp->h.md_pi = rdp->h.md_pi - 1; + } + } else { + rc = mdb_add_node(txn, dbi, rdp->h.md_parent, rdp->h.md_pi, + &sepkey, NULL, rdp->p.mp_pgno, 0); + } + if (IS_LEAF2(&rdp->p)) { + return rc; + } + if (rc != MDB_SUCCESS) { + free(copy); + return rc; + } + + for (i = j = 0; i <= NUMKEYS(copy); j++) { + if (i < split_indx) { + /* Re-insert in left sibling. */ + pdp = mdp; + } else { + /* Insert in right sibling. */ + if (i == split_indx) + /* Reset insert index for right sibling. */ + j = (i == newindx && ins_new); + pdp = rdp; + } + + if (i == newindx && !ins_new) { + /* Insert the original entry that caused the split. */ + rkey.mv_data = newkey->mv_data; + rkey.mv_size = newkey->mv_size; + if (IS_LEAF(&mdp->p)) { + rdata.mv_data = newdata->mv_data; + rdata.mv_size = newdata->mv_size; + } else + pgno = newpgno; + flags = 0; + + ins_new = 1; + + /* Update page and index for the new key. */ + *newindxp = j; + *mpp = &pdp->p; + } else if (i == NUMKEYS(copy)) { + break; + } else { + node = NODEPTR(copy, i); + rkey.mv_data = NODEKEY(node); + rkey.mv_size = node->mn_ksize; + if (IS_LEAF(&mdp->p)) { + rdata.mv_data = NODEDATA(node); + rdata.mv_size = node->mn_dsize; + } else + pgno = NODEPGNO(node); + flags = node->mn_flags; + + i++; + } + + if (!IS_LEAF(&mdp->p) && j == 0) { + /* First branch index doesn't need key data. */ + rkey.mv_size = 0; + } + + rc = mdb_add_node(txn, dbi, &pdp->p, j, &rkey, &rdata, pgno,flags); + } + + free(copy); + return rc; +} + +static int +mdb_put0(MDB_txn *txn, MDB_dbi dbi, + MDB_val *key, MDB_val *data, unsigned int flags) +{ + int rc = MDB_SUCCESS, exact; + unsigned int ki; + MDB_node *leaf; + MDB_pageparent mpp; + MDB_val xdata, *rdata, dkey; + MDB_db dummy; + char dbuf[PAGESIZE]; + int do_sub = 0; + size_t nsize; + DKBUF; + + DPRINTF("==> put db %u key [%s], size %zu, data size %zu", + dbi, DKEY(key), key->mv_size, data->mv_size); + + dkey.mv_size = 0; + mpp.mp_parent = NULL; + mpp.mp_pi = 0; + rc = mdb_search_page(txn, dbi, key, NULL, 1, &mpp); + if (rc == MDB_SUCCESS) { + leaf = mdb_search_node(txn, dbi, mpp.mp_page, key, &exact, &ki); + if (leaf && exact) { + if (flags == MDB_NOOVERWRITE) { + DPRINTF("duplicate key [%s]", DKEY(key)); + return MDB_KEYEXIST; + } + /* there's only a key anyway, so this is a no-op */ + if (IS_LEAF2(mpp.mp_page)) + return MDB_SUCCESS; + + if (F_ISSET(txn->mt_dbs[dbi].md_flags, MDB_DUPSORT)) { + /* Was a single item before, must convert now */ + if (!F_ISSET(leaf->mn_flags, F_DUPDATA)) { + dkey.mv_size = NODEDSZ(leaf); + dkey.mv_data = dbuf; + memcpy(dbuf, NODEDATA(leaf), dkey.mv_size); + /* data matches, ignore it */ + if (!mdb_dcmp(txn, dbi, data, &dkey)) + return (flags == MDB_NODUPDATA) ? MDB_KEYEXIST : MDB_SUCCESS; + memset(&dummy, 0, sizeof(dummy)); + if (txn->mt_dbs[dbi].md_flags & MDB_DUPFIXED) { + dummy.md_pad = data->mv_size; + dummy.md_flags = MDB_DUPFIXED; + if (txn->mt_dbs[dbi].md_flags & MDB_INTEGERDUP) + dummy.md_flags |= MDB_INTEGERKEY; + } + dummy.md_root = P_INVALID; + if (dkey.mv_size == sizeof(MDB_db)) { + memcpy(NODEDATA(leaf), &dummy, sizeof(dummy)); + goto put_sub; + } + mdb_del_node(mpp.mp_page, ki, 0); + do_sub = 1; + rdata = &xdata; + xdata.mv_size = sizeof(MDB_db); + xdata.mv_data = &dummy; + goto new_sub; + } + goto put_sub; + } + /* same size, just replace it */ + if (NODEDSZ(leaf) == data->mv_size) { + memcpy(NODEDATA(leaf), data->mv_data, data->mv_size); + goto done; + } + mdb_del_node(mpp.mp_page, ki, 0); + } + if (leaf == NULL) { /* append if not found */ + ki = NUMKEYS(mpp.mp_page); + DPRINTF("appending key at index %i", ki); + } + } else if (rc == MDB_NOTFOUND) { + MDB_dpage *dp; + /* new file, just write a root leaf page */ + DPUTS("allocating new root leaf page"); + if ((dp = mdb_new_page(txn, dbi, P_LEAF, 1)) == NULL) { + return ENOMEM; + } + mpp.mp_page = &dp->p; + txn->mt_dbs[dbi].md_root = mpp.mp_page->mp_pgno; + txn->mt_dbs[dbi].md_depth++; + txn->mt_dbxs[dbi].md_dirty = 1; + if ((txn->mt_dbs[dbi].md_flags & (MDB_DUPSORT|MDB_DUPFIXED)) == MDB_DUPFIXED) + mpp.mp_page->mp_flags |= P_LEAF2; + ki = 0; + } + else + goto done; + + assert(IS_LEAF(mpp.mp_page)); + DPRINTF("there are %u keys, should insert new key at index %i", + NUMKEYS(mpp.mp_page), ki); + + rdata = data; + +new_sub: + nsize = IS_LEAF2(mpp.mp_page) ? key->mv_size : mdb_leaf_size(txn->mt_env, key, rdata); + if (SIZELEFT(mpp.mp_page) < nsize) { + rc = mdb_split(txn, dbi, &mpp.mp_page, &ki, key, rdata, P_INVALID); + } else { + /* There is room already in this leaf page. */ + rc = mdb_add_node(txn, dbi, mpp.mp_page, ki, key, rdata, 0, 0); + } + + if (rc != MDB_SUCCESS) + txn->mt_flags |= MDB_TXN_ERROR; + else { + /* Remember if we just added a subdatabase */ + if (flags & F_SUBDATA) { + leaf = NODEPTR(mpp.mp_page, ki); + leaf->mn_flags |= F_SUBDATA; + } + + /* Now store the actual data in the child DB. Note that we're + * storing the user data in the keys field, so there are strict + * size limits on dupdata. The actual data fields of the child + * DB are all zero size. + */ + if (do_sub) { + MDB_xcursor mx; + + leaf = NODEPTR(mpp.mp_page, ki); +put_sub: + mdb_xcursor_init0(txn, dbi, &mx); + mdb_xcursor_init1(txn, dbi, &mx, leaf); + xdata.mv_size = 0; + xdata.mv_data = ""; + if (flags == MDB_NODUPDATA) + flags = MDB_NOOVERWRITE; + /* converted, write the original data first */ + if (dkey.mv_size) { + rc = mdb_put0(&mx.mx_txn, mx.mx_cursor.mc_dbi, &dkey, &xdata, flags); + if (rc) return rc; + leaf->mn_flags |= F_DUPDATA; + } + rc = mdb_put0(&mx.mx_txn, mx.mx_cursor.mc_dbi, data, &xdata, flags); + mdb_xcursor_fini(txn, dbi, &mx); + memcpy(NODEDATA(leaf), &mx.mx_txn.mt_dbs[mx.mx_cursor.mc_dbi], + sizeof(MDB_db)); + } + txn->mt_dbs[dbi].md_entries++; + } + +done: + return rc; +} + +int +mdb_put(MDB_txn *txn, MDB_dbi dbi, + MDB_val *key, MDB_val *data, unsigned int flags) +{ + assert(key != NULL); + assert(data != NULL); + + if (txn == NULL || !dbi || dbi >= txn->mt_numdbs) + return EINVAL; + + if (F_ISSET(txn->mt_flags, MDB_TXN_RDONLY)) { + return EINVAL; + } + + if (key->mv_size == 0 || key->mv_size > MAXKEYSIZE) { + return EINVAL; + } + + if ((flags & (MDB_NOOVERWRITE|MDB_NODUPDATA)) != flags) + return EINVAL; + + return mdb_put0(txn, dbi, key, data, flags); +} + +int +mdb_env_set_flags(MDB_env *env, unsigned int flag, int onoff) +{ +#define CHANGEABLE (MDB_NOSYNC) + if ((flag & CHANGEABLE) != flag) + return EINVAL; + if (onoff) + env->me_flags |= flag; + else + env->me_flags &= ~flag; + return MDB_SUCCESS; +} + +int +mdb_env_get_flags(MDB_env *env, unsigned int *arg) +{ + if (!env || !arg) + return EINVAL; + + *arg = env->me_flags; + return MDB_SUCCESS; +} + +int +mdb_env_get_path(MDB_env *env, const char **arg) +{ + if (!env || !arg) + return EINVAL; + + *arg = env->me_path; + return MDB_SUCCESS; +} + +static int +mdb_stat0(MDB_env *env, MDB_db *db, MDB_stat *arg) +{ + arg->ms_psize = env->me_psize; + arg->ms_depth = db->md_depth; + arg->ms_branch_pages = db->md_branch_pages; + arg->ms_leaf_pages = db->md_leaf_pages; + arg->ms_overflow_pages = db->md_overflow_pages; + arg->ms_entries = db->md_entries; + + return MDB_SUCCESS; +} +int +mdb_env_stat(MDB_env *env, MDB_stat *arg) +{ + if (env == NULL || arg == NULL) + return EINVAL; + + return mdb_stat0(env, &env->me_meta->mm_dbs[MAIN_DBI], arg); +} + +int mdb_open(MDB_txn *txn, const char *name, unsigned int flags, MDB_dbi *dbi) +{ + MDB_val key, data; + MDB_dbi i; + int rc, dirty = 0; + size_t len; + + /* main DB? */ + if (!name) { + *dbi = MAIN_DBI; + if (flags & (MDB_DUPSORT|MDB_REVERSEKEY|MDB_INTEGERKEY)) + txn->mt_dbs[MAIN_DBI].md_flags |= (flags & (MDB_DUPSORT|MDB_REVERSEKEY|MDB_INTEGERKEY)); + return MDB_SUCCESS; + } + + /* Is the DB already open? */ + len = strlen(name); + for (i=2; imt_numdbs; i++) { + if (len == txn->mt_dbxs[i].md_name.mv_size && + !strncmp(name, txn->mt_dbxs[i].md_name.mv_data, len)) { + *dbi = i; + return MDB_SUCCESS; + } + } + + if (txn->mt_numdbs >= txn->mt_env->me_maxdbs - 1) + return ENFILE; + + /* Find the DB info */ + key.mv_size = len; + key.mv_data = (void *)name; + rc = mdb_get(txn, MAIN_DBI, &key, &data); + + /* Create if requested */ + if (rc == MDB_NOTFOUND && (flags & MDB_CREATE)) { + MDB_db dummy; + data.mv_size = sizeof(MDB_db); + data.mv_data = &dummy; + memset(&dummy, 0, sizeof(dummy)); + dummy.md_root = P_INVALID; + dummy.md_flags = flags & 0xffff; + rc = mdb_put0(txn, MAIN_DBI, &key, &data, F_SUBDATA); + dirty = 1; + } + + /* OK, got info, add to table */ + if (rc == MDB_SUCCESS) { + txn->mt_dbxs[txn->mt_numdbs].md_name.mv_data = strdup(name); + txn->mt_dbxs[txn->mt_numdbs].md_name.mv_size = len; + txn->mt_dbxs[txn->mt_numdbs].md_cmp = NULL; + txn->mt_dbxs[txn->mt_numdbs].md_dcmp = NULL; + txn->mt_dbxs[txn->mt_numdbs].md_rel = NULL; + txn->mt_dbxs[txn->mt_numdbs].md_parent = MAIN_DBI; + txn->mt_dbxs[txn->mt_numdbs].md_dirty = dirty; + memcpy(&txn->mt_dbs[txn->mt_numdbs], data.mv_data, sizeof(MDB_db)); + *dbi = txn->mt_numdbs; + txn->mt_env->me_dbs[0][txn->mt_numdbs] = txn->mt_dbs[txn->mt_numdbs]; + txn->mt_env->me_dbs[1][txn->mt_numdbs] = txn->mt_dbs[txn->mt_numdbs]; + txn->mt_numdbs++; + } + + return rc; +} + +int mdb_stat(MDB_txn *txn, MDB_dbi dbi, MDB_stat *arg) +{ + if (txn == NULL || arg == NULL || dbi >= txn->mt_numdbs) + return EINVAL; + + return mdb_stat0(txn->mt_env, &txn->mt_dbs[dbi], arg); +} + +void mdb_close(MDB_txn *txn, MDB_dbi dbi) +{ + char *ptr; + if (dbi <= MAIN_DBI || dbi >= txn->mt_numdbs) + return; + ptr = txn->mt_dbxs[dbi].md_name.mv_data; + txn->mt_dbxs[dbi].md_name.mv_data = NULL; + txn->mt_dbxs[dbi].md_name.mv_size = 0; + free(ptr); +} + +int mdb_set_compare(MDB_txn *txn, MDB_dbi dbi, MDB_cmp_func *cmp) +{ + if (txn == NULL || !dbi || dbi >= txn->mt_numdbs) + return EINVAL; + + txn->mt_dbxs[dbi].md_cmp = cmp; + return MDB_SUCCESS; +} + +int mdb_set_dupsort(MDB_txn *txn, MDB_dbi dbi, MDB_cmp_func *cmp) +{ + if (txn == NULL || !dbi || dbi >= txn->mt_numdbs) + return EINVAL; + + txn->mt_dbxs[dbi].md_dcmp = cmp; + return MDB_SUCCESS; +} + +int mdb_set_relfunc(MDB_txn *txn, MDB_dbi dbi, MDB_rel_func *rel) +{ + if (txn == NULL || !dbi || dbi >= txn->mt_numdbs) + return EINVAL; + + txn->mt_dbxs[dbi].md_rel = rel; + return MDB_SUCCESS; +}