From: Howard Chu Date: Wed, 21 Sep 2011 21:14:11 +0000 (-0700) Subject: Track changes to all cursors. X-Git-Tag: OPENLDAP_REL_ENG_2_4_27~148^2~18 X-Git-Url: https://git.sur5r.net/?a=commitdiff_plain;h=b9d13a29e6c4c2742277c82bdc646c32d364a619;p=openldap Track changes to all cursors. For any change to a page or node, update all other cursors pointing at the same page (or node). Cursors are now stored in a linked list off their owning transaction. Cursors are all closed when the transaction ends. Cursors in parent transactions are updated when their child transaction commits. --- diff --git a/libraries/libmdb/mdb.c b/libraries/libmdb/mdb.c index 143b5a1636..28d5001c48 100644 --- a/libraries/libmdb/mdb.c +++ b/libraries/libmdb/mdb.c @@ -731,6 +731,8 @@ struct MDB_txn { #define DB_DIRTY 0x01 /**< DB was written in this txn */ #define DB_STALE 0x02 /**< DB record is older than txnID */ /** @} */ + /** Array of cursors for each DB */ + MDB_cursor **mt_cursors; /** Array of flags for each DB */ unsigned char *mt_dbflags; /** Number of DB records in use. This number only ever increments; @@ -762,6 +764,10 @@ struct MDB_xcursor; /** Cursors are used for all DB operations */ struct MDB_cursor { + /** Next cursor on this DB in this txn */ + MDB_cursor *mc_next; + /** Original cursor if this is a shadow */ + MDB_cursor *mc_orig; /** Context used for databases with #MDB_DUPSORT, otherwise NULL */ struct MDB_xcursor *mc_xcursor; /** The transaction that owns this cursor */ @@ -783,6 +789,8 @@ struct MDB_cursor { */ #define C_INITIALIZED 0x01 /**< cursor has been initialized and is valid */ #define C_EOF 0x02 /**< No more data */ +#define C_SUB 0x04 /**< Cursor is a sub-cursor */ +#define C_SHADOW 0x08 /**< Cursor is a dup from a parent txn */ /** @} */ unsigned int mc_flags; /**< @ref mdb_cursor */ MDB_page *mc_pg[CURSOR_STACK]; /**< stack of pushed pages */ @@ -1160,6 +1168,26 @@ mdb_page_touch(MDB_cursor *mc) mp->mp_flags |= P_DIRTY; finish: + /* Adjust other cursors pointing to mp */ + if (mc->mc_flags & C_SUB) { + MDB_cursor *m2, *m3; + MDB_dbi dbi = mc->mc_dbi-1; + + for (m2 = mc->mc_txn->mt_cursors[dbi]; m2; m2=m2->mc_next) { + m3 = &m2->mc_xcursor->mx_cursor; + if (m3->mc_pg[mc->mc_top] == mc->mc_pg[mc->mc_top]) { + m3->mc_pg[mc->mc_top] = mp; + } + } + } else { + MDB_cursor *m2; + + for (m2 = mc->mc_txn->mt_cursors[mc->mc_dbi]; m2; m2=m2->mc_next) { + if (m2->mc_pg[mc->mc_top] == mc->mc_pg[mc->mc_top]) { + m2->mc_pg[mc->mc_top] = mp; + } + } + } mc->mc_pg[mc->mc_top] = mp; /** If this page has a parent, update the parent to point to * this new page. @@ -1208,6 +1236,92 @@ mdb_env_sync(MDB_env *env, int force) return rc; } +/** Make shadow copies of all of parent txn's cursors */ +static int +mdb_cursor_shadow(MDB_txn *src, MDB_txn *dst) +{ + MDB_cursor *mc, *m2; + unsigned int i, j, size; + + for (i=0;imt_numdbs; i++) { + if (src->mt_cursors[i]) { + size = sizeof(MDB_cursor); + if (src->mt_cursors[i]->mc_xcursor) + size += sizeof(MDB_xcursor); + for (m2 = src->mt_cursors[i]; m2; m2=m2->mc_next) { + mc = malloc(size); + if (!mc) + return ENOMEM; + mc->mc_orig = m2; + mc->mc_txn = dst; + mc->mc_dbi = i; + mc->mc_db = &dst->mt_dbs[i]; + mc->mc_dbx = m2->mc_dbx; + mc->mc_dbflag = &dst->mt_dbflags[i]; + mc->mc_snum = m2->mc_snum; + mc->mc_top = m2->mc_top; + mc->mc_flags = m2->mc_flags | C_SHADOW; + for (j=0; jmc_snum; j++) { + mc->mc_pg[j] = m2->mc_pg[j]; + mc->mc_ki[j] = m2->mc_ki[j]; + } + if (m2->mc_xcursor) { + MDB_xcursor *mx, *mx2; + mx = (MDB_xcursor *)(mc+1); + mc->mc_xcursor = mx; + mx2 = m2->mc_xcursor; + mx->mx_db = mx2->mx_db; + mx->mx_dbx = mx2->mx_dbx; + mx->mx_dbflag = mx2->mx_dbflag; + mx->mx_cursor.mc_txn = dst; + mx->mx_cursor.mc_dbi = mx2->mx_cursor.mc_dbi; + mx->mx_cursor.mc_db = &mx->mx_db; + mx->mx_cursor.mc_dbx = &mx->mx_dbx; + mx->mx_cursor.mc_dbflag = &mx->mx_dbflag; + mx->mx_cursor.mc_snum = mx2->mx_cursor.mc_snum; + mx->mx_cursor.mc_top = mx2->mx_cursor.mc_top; + mx->mx_cursor.mc_flags = mx2->mx_cursor.mc_flags | C_SHADOW; + for (j=0; jmx_cursor.mc_snum; j++) { + mx->mx_cursor.mc_pg[j] = mx2->mx_cursor.mc_pg[j]; + mx->mx_cursor.mc_ki[j] = mx2->mx_cursor.mc_ki[j]; + } + } else { + mc->mc_xcursor = NULL; + } + mc->mc_next = dst->mt_cursors[i]; + dst->mt_cursors[i] = mc; + } + } + } + return MDB_SUCCESS; +} + +/** Merge shadow cursors back into parent's */ +static void +mdb_cursor_merge(MDB_txn *txn) +{ + MDB_dbi i; + for (i=0; imt_numdbs; i++) { + if (txn->mt_cursors[i]) { + MDB_cursor *mc; + while ((mc = txn->mt_cursors[i])) { + txn->mt_cursors[i] = mc->mc_next; + if (mc->mc_flags & C_SHADOW) { + MDB_cursor *m2 = mc->mc_orig; + unsigned int j; + m2->mc_snum = mc->mc_snum; + m2->mc_top = mc->mc_top; + for (j=0; jmc_snum; j++) { + m2->mc_pg[j] = mc->mc_pg[j]; + m2->mc_ki[j] = mc->mc_ki[j]; + } + } + free(mc); + } + } + } +} + static void mdb_txn_reset0(MDB_txn *txn); @@ -1312,7 +1426,7 @@ int mdb_txn_begin(MDB_env *env, MDB_txn *parent, unsigned int flags, MDB_txn **ret) { MDB_txn *txn; - int rc; + int rc, size; if (env->me_flags & MDB_FATAL_ERROR) { DPUTS("environment had fatal error, must shutdown!"); @@ -1324,16 +1438,22 @@ mdb_txn_begin(MDB_env *env, MDB_txn *parent, unsigned int flags, MDB_txn **ret) return EINVAL; } } - if ((txn = calloc(1, sizeof(MDB_txn) + - env->me_maxdbs * (sizeof(MDB_db)+1))) == NULL) { + size = sizeof(MDB_txn) + env->me_maxdbs * (sizeof(MDB_db)+1); + if (!(flags & MDB_RDONLY)) + size += env->me_maxdbs * sizeof(MDB_cursor *); + + if ((txn = calloc(1, size)) == NULL) { DPRINTF("calloc: %s", strerror(ErrCode())); return ENOMEM; } txn->mt_dbs = (MDB_db *)(txn+1); if (flags & MDB_RDONLY) { txn->mt_flags |= MDB_TXN_RDONLY; + txn->mt_dbflags = (unsigned char *)(txn->mt_dbs + env->me_maxdbs); + } else { + txn->mt_cursors = (MDB_cursor **)(txn->mt_dbs + env->me_maxdbs); + txn->mt_dbflags = (unsigned char *)(txn->mt_cursors + env->me_maxdbs); } - txn->mt_dbflags = (unsigned char *)(txn->mt_dbs + env->me_maxdbs); txn->mt_env = env; if (parent) { @@ -1359,6 +1479,7 @@ mdb_txn_begin(MDB_env *env, MDB_txn *parent, unsigned int flags, MDB_txn **ret) txn->mt_dbxs = parent->mt_dbxs; memcpy(txn->mt_dbs, parent->mt_dbs, txn->mt_numdbs * sizeof(MDB_db)); memcpy(txn->mt_dbflags, parent->mt_dbflags, txn->mt_numdbs); + mdb_cursor_shadow(parent, txn); rc = 0; } else { rc = mdb_txn_renew0(txn); @@ -1390,6 +1511,17 @@ mdb_txn_reset0(MDB_txn *txn) MDB_page *dp; unsigned int i; + /* close(free) all cursors */ + for (i=0; imt_numdbs; i++) { + if (txn->mt_cursors[i]) { + MDB_cursor *mc; + while ((mc = txn->mt_cursors[i])) { + txn->mt_cursors[i] = mc->mc_next; + free(mc); + } + } + } + /* 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; @@ -1497,7 +1629,6 @@ mdb_txn_commit(MDB_txn *txn) return MDB_SUCCESS; } - if (F_ISSET(txn->mt_flags, MDB_TXN_ERROR)) { DPUTS("error flag is set, can't commit"); if (txn->mt_parent) @@ -1506,6 +1637,9 @@ mdb_txn_commit(MDB_txn *txn) return EINVAL; } + /* Merge (and close) our cursors with parent's */ + mdb_cursor_merge(txn); + if (txn->mt_parent) { MDB_db *ip, *jp; MDB_dbi i; @@ -1532,21 +1666,11 @@ mdb_txn_commit(MDB_txn *txn) src = txn->mt_u.dirty_list; x = mdb_mid2l_search(dst, src[1].mid); for (y=1; y<=src[0].mid; y++) { - MDB_page *mp; while (x <= dst[0].mid && dst[x].mid != src[y].mid) x++; if (x > dst[0].mid) break; - mp = dst[x].mptr; - dp = src[y].mptr; - mp->mp_lower = dp->mp_lower; - mp->mp_upper = dp->mp_upper; - if (IS_LEAF2(mp)) { - memcpy(METADATA(mp), METADATA(dp), NUMKEYS(mp) * mp->mp_pad); - } else { - memcpy((char *)mp+mp->mp_upper, (char *)dp+dp->mp_upper, - txn->mt_env->me_psize - mp->mp_upper); - } - free(src[y].mptr); + free(dst[x].mptr); + dst[x].mptr = src[y].mptr; } x = dst[0].mid; for (; y<=src[0].mid; y++) { @@ -2838,6 +2962,20 @@ mdb_node_search(MDB_cursor *mc, MDB_val *key, int *exactp) return node; } +#if 0 +static void +mdb_cursor_adjust(MDB_cursor *mc, func) +{ + MDB_cursor *m2; + + for (m2 = mc->mc_txn->mt_cursors[mc->mc_dbi]; m2; m2=m2->mc_next) { + if (m2->mc_pg[m2->mc_top] == mc->mc_pg[mc->mc_top]) { + func(mc, m2); + } + } +} +#endif + /** Pop a page off the top of the cursor's stack. */ static void mdb_cursor_pop(MDB_cursor *mc) @@ -3790,12 +3928,13 @@ top: if (flags == MDB_CURRENT) goto current; - /* create a fake page for the dup items */ dkey.mv_size = NODEDSZ(leaf); dkey.mv_data = NODEDATA(leaf); /* data matches, ignore it */ if (!mc->mc_dbx->md_dcmp(data, &dkey)) return (flags == MDB_NODUPDATA) ? MDB_KEYEXIST : MDB_SUCCESS; + + /* create a fake page for the dup items */ memcpy(dbuf, dkey.mv_data, dkey.mv_size); dkey.mv_data = dbuf; fp = (MDB_page *)pbuf; @@ -3913,6 +4052,26 @@ new_sub: } else { /* There is room already in this leaf page. */ rc = mdb_node_add(mc, mc->mc_ki[mc->mc_top], key, rdata, 0, 0); + if (rc == 0 && !do_sub) { + /* Adjust other cursors pointing to mp */ + MDB_cursor *m2, *m3; + MDB_dbi dbi = mc->mc_dbi; + unsigned i = mc->mc_top; + MDB_page *mp = mc->mc_pg[i]; + + if (mc->mc_flags & C_SUB) + dbi--; + + for (m2 = mc->mc_txn->mt_cursors[dbi]; m2; m2=m2->mc_next) { + if (mc->mc_flags & C_SUB) + m3 = &m2->mc_xcursor->mx_cursor; + else + m3 = m2; + if (m3->mc_pg[i] == mp && m3->mc_ki[i] >= mc->mc_ki[i]) { + m3->mc_ki[i]++; + } + } + } } if (rc != MDB_SUCCESS) @@ -3946,6 +4105,18 @@ put_sub: rc = mdb_cursor_put(&mc->mc_xcursor->mx_cursor, &dkey, &xdata, xflags); if (rc) return rc; + { + /* Adjust other cursors pointing to mp */ + MDB_cursor *m2; + unsigned i = mc->mc_top; + MDB_page *mp = mc->mc_pg[i]; + + for (m2 = mc->mc_txn->mt_cursors[mc->mc_dbi]; m2; m2=m2->mc_next) { + if (m2->mc_pg[i] == mp && m2->mc_ki[i] == mc->mc_ki[i]) { + mdb_xcursor_init1(m2, leaf); + } + } + } } rc = mdb_cursor_put(&mc->mc_xcursor->mx_cursor, data, &xdata, xflags); if (flags & F_SUBDATA) { @@ -4373,7 +4544,7 @@ mdb_xcursor_init1(MDB_cursor *mc, MDB_node *node) MDB_db *db = NODEDATA(node); mx->mx_db = *db; mx->mx_cursor.mc_snum = 0; - mx->mx_cursor.mc_flags = 0; + mx->mx_cursor.mc_flags = C_SUB; } else { MDB_page *fp = NODEDATA(node); mx->mx_db.md_pad = mc->mc_pg[mc->mc_top]->mp_pad; @@ -4385,7 +4556,7 @@ mdb_xcursor_init1(MDB_cursor *mc, MDB_node *node) mx->mx_db.md_entries = NUMKEYS(fp); mx->mx_db.md_root = fp->mp_pgno; mx->mx_cursor.mc_snum = 1; - mx->mx_cursor.mc_flags = C_INITIALIZED; + mx->mx_cursor.mc_flags = C_INITIALIZED|C_SUB; mx->mx_cursor.mc_top = 0; mx->mx_cursor.mc_pg[0] = fp; mx->mx_cursor.mc_ki[0] = 0; @@ -4410,6 +4581,7 @@ mdb_xcursor_init1(MDB_cursor *mc, MDB_node *node) static void mdb_cursor_init(MDB_cursor *mc, MDB_txn *txn, MDB_dbi dbi, MDB_xcursor *mx) { + mc->mc_orig = NULL; mc->mc_dbi = dbi; mc->mc_txn = txn; mc->mc_db = &txn->mt_dbs[dbi]; @@ -4444,6 +4616,10 @@ mdb_cursor_open(MDB_txn *txn, MDB_dbi dbi, MDB_cursor **ret) mx = (MDB_xcursor *)(mc + 1); } mdb_cursor_init(mc, txn, dbi, mx); + if (txn->mt_cursors) { + mc->mc_next = txn->mt_cursors[dbi]; + txn->mt_cursors[dbi] = mc; + } } else { return ENOMEM; } @@ -4481,6 +4657,13 @@ void mdb_cursor_close(MDB_cursor *mc) { if (mc != NULL) { + /* remove from txn, if tracked */ + if (mc->mc_txn->mt_cursors) { + MDB_cursor **prev = &mc->mc_txn->mt_cursors[mc->mc_dbi]; + while (*prev && *prev != mc) prev = &(*prev)->mc_next; + if (*prev == mc) + *prev = mc->mc_next; + } free(mc); } } @@ -4594,6 +4777,28 @@ mdb_node_move(MDB_cursor *csrc, MDB_cursor *cdst) */ mdb_node_del(csrc->mc_pg[csrc->mc_top], csrc->mc_ki[csrc->mc_top], key.mv_size); + { + /* Adjust other cursors pointing to mp */ + MDB_cursor *m2, *m3; + MDB_dbi dbi = csrc->mc_dbi; + MDB_page *mp = csrc->mc_pg[csrc->mc_top]; + + if (csrc->mc_flags & C_SUB) + dbi--; + + for (m2 = csrc->mc_txn->mt_cursors[dbi]; m2; m2=m2->mc_next) { + if (csrc->mc_flags & C_SUB) + m3 = &m2->mc_xcursor->mx_cursor; + else + m3 = m2; + if (m3->mc_pg[csrc->mc_top] == mp && m3->mc_ki[csrc->mc_top] == + csrc->mc_ki[csrc->mc_top]) { + m3->mc_pg[csrc->mc_top] = cdst->mc_pg[cdst->mc_top]; + m3->mc_ki[csrc->mc_top] = cdst->mc_ki[cdst->mc_top]; + } + } + } + /* Update the parent separators. */ if (csrc->mc_ki[csrc->mc_top] == 0) { @@ -4657,6 +4862,7 @@ mdb_page_merge(MDB_cursor *csrc, MDB_cursor *cdst) indx_t i, j; MDB_node *srcnode; MDB_val key, data; + unsigned nkeys; DPRINTF("merging page %zu into %zu", csrc->mc_pg[csrc->mc_top]->mp_pgno, cdst->mc_pg[cdst->mc_top]->mp_pgno); @@ -4670,7 +4876,7 @@ mdb_page_merge(MDB_cursor *csrc, MDB_cursor *cdst) /* Move all nodes from src to dst. */ - j = NUMKEYS(cdst->mc_pg[cdst->mc_top]); + j = nkeys = NUMKEYS(cdst->mc_pg[cdst->mc_top]); if (IS_LEAF2(csrc->mc_pg[csrc->mc_top])) { key.mv_size = csrc->mc_db->md_pad; key.mv_data = METADATA(csrc->mc_pg[csrc->mc_top]); @@ -4711,6 +4917,26 @@ mdb_page_merge(MDB_cursor *csrc, MDB_cursor *cdst) csrc->mc_db->md_leaf_pages--; else csrc->mc_db->md_branch_pages--; + { + /* Adjust other cursors pointing to mp */ + MDB_cursor *m2, *m3; + MDB_dbi dbi = csrc->mc_dbi; + MDB_page *mp = cdst->mc_pg[cdst->mc_top]; + + if (csrc->mc_flags & C_SUB) + dbi--; + + for (m2 = csrc->mc_txn->mt_cursors[dbi]; m2; m2=m2->mc_next) { + if (csrc->mc_flags & C_SUB) + m3 = &m2->mc_xcursor->mx_cursor; + else + m3 = m2; + if (m3->mc_pg[csrc->mc_top] == csrc->mc_pg[csrc->mc_top]) { + m3->mc_pg[csrc->mc_top] = mp; + m3->mc_ki[csrc->mc_top] += nkeys; + } + } + } mdb_cursor_pop(csrc); return mdb_rebalance(csrc); @@ -4763,22 +4989,61 @@ mdb_rebalance(MDB_cursor *mc) } if (mc->mc_snum < 2) { - if (NUMKEYS(mc->mc_pg[mc->mc_top]) == 0) { + MDB_page *mp = mc->mc_pg[0]; + if (NUMKEYS(mp) == 0) { DPUTS("tree is completely empty"); mc->mc_db->md_root = P_INVALID; mc->mc_db->md_depth = 0; mc->mc_db->md_leaf_pages = 0; - mdb_midl_append(&mc->mc_txn->mt_free_pgs, mc->mc_pg[mc->mc_top]->mp_pgno); + mdb_midl_append(&mc->mc_txn->mt_free_pgs, mp->mp_pgno); mc->mc_snum = 0; - } else if (IS_BRANCH(mc->mc_pg[mc->mc_top]) && NUMKEYS(mc->mc_pg[mc->mc_top]) == 1) { + mc->mc_top = 0; + { + /* Adjust other cursors pointing to mp */ + MDB_cursor *m2, *m3; + MDB_dbi dbi = mc->mc_dbi; + + if (mc->mc_flags & C_SUB) + dbi--; + + for (m2 = mc->mc_txn->mt_cursors[dbi]; m2; m2=m2->mc_next) { + if (mc->mc_flags & C_SUB) + m3 = &m2->mc_xcursor->mx_cursor; + else + m3 = m2; + if (m3->mc_pg[0] == mp) { + m3->mc_snum = 0; + m3->mc_top = 0; + } + } + } + } else if (IS_BRANCH(mp) && NUMKEYS(mp) == 1) { DPUTS("collapsing root page!"); - mdb_midl_append(&mc->mc_txn->mt_free_pgs, mc->mc_pg[mc->mc_top]->mp_pgno); - mc->mc_db->md_root = NODEPGNO(NODEPTR(mc->mc_pg[mc->mc_top], 0)); + mdb_midl_append(&mc->mc_txn->mt_free_pgs, mp->mp_pgno); + mc->mc_db->md_root = NODEPGNO(NODEPTR(mp, 0)); if ((rc = mdb_page_get(mc->mc_txn, mc->mc_db->md_root, - &mc->mc_pg[mc->mc_top]))) + &mc->mc_pg[0]))) return rc; mc->mc_db->md_depth--; mc->mc_db->md_branch_pages--; + { + /* Adjust other cursors pointing to mp */ + MDB_cursor *m2, *m3; + MDB_dbi dbi = mc->mc_dbi; + + if (mc->mc_flags & C_SUB) + dbi--; + + for (m2 = mc->mc_txn->mt_cursors[dbi]; m2; m2=m2->mc_next) { + if (mc->mc_flags & C_SUB) + m3 = &m2->mc_xcursor->mx_cursor; + else + m3 = m2; + if (m3->mc_pg[0] == mp) { + m3->mc_pg[0] = mc->mc_pg[0]; + } + } + } } else DPUTS("root page doesn't need rebalancing"); return MDB_SUCCESS; @@ -4925,7 +5190,7 @@ static int mdb_page_split(MDB_cursor *mc, MDB_val *newkey, MDB_val *newdata, pgno_t newpgno) { uint8_t flags; - int rc = MDB_SUCCESS, ins_new = 0; + int rc = MDB_SUCCESS, ins_new = 0, new_root = 0; indx_t newindx; pgno_t pgno = 0; unsigned int i, j, split_indx, nkeys, pmax; @@ -4955,6 +5220,7 @@ mdb_page_split(MDB_cursor *mc, MDB_val *newkey, MDB_val *newdata, pgno_t newpgno mc->mc_db->md_root = pp->mp_pgno; DPRINTF("root split! new root = %zu", pp->mp_pgno); mc->mc_db->md_depth++; + new_root = 1; /* Add left (implicit) pointer. */ if ((rc = mdb_node_add(mc, 0, NULL, NULL, mp->mp_pgno, 0)) != MDB_SUCCESS) { @@ -5102,12 +5368,12 @@ newsep: rc = mdb_node_add(&mn, mn.mc_ki[ptop], &sepkey, NULL, rp->mp_pgno, 0); mn.mc_top++; } - if (IS_LEAF2(rp)) { - return rc; - } if (rc != MDB_SUCCESS) { return rc; } + if (IS_LEAF2(rp)) { + goto done; + } /* Move half of the keys to the right sibling. */ @@ -5183,6 +5449,39 @@ newsep: /* return tmp page to freelist */ copy->mp_next = mc->mc_txn->mt_env->me_dpages; mc->mc_txn->mt_env->me_dpages = copy; +done: + { + /* Adjust other cursors pointing to mp */ + MDB_cursor *m2, *m3; + MDB_dbi dbi = mc->mc_dbi; + + if (mc->mc_flags & C_SUB) + dbi--; + + for (m2 = mc->mc_txn->mt_cursors[dbi]; m2; m2=m2->mc_next) { + if (mc->mc_flags & C_SUB) + m3 = &m2->mc_xcursor->mx_cursor; + else + m3 = m2; + if (new_root) { + /* root split */ + for (i=m3->mc_top; i>0; i--) { + m3->mc_ki[i+1] = m3->mc_ki[i]; + m3->mc_pg[i+1] = m3->mc_pg[i]; + } + m3->mc_ki[0] = mc->mc_ki[0]; + m3->mc_pg[0] = mc->mc_pg[0]; + m3->mc_snum++; + m3->mc_top++; + } + if (m3->mc_pg[mc->mc_top] == mp) { + if (m3->mc_ki[m3->mc_top] >= split_indx) { + m3->mc_pg[m3->mc_top] = rp; + m3->mc_ki[m3->mc_top] -= split_indx; + } + } + } + } return rc; } diff --git a/libraries/libmdb/mdb.h b/libraries/libmdb/mdb.h index 1672d81c16..14105b26e4 100644 --- a/libraries/libmdb/mdb.h +++ b/libraries/libmdb/mdb.h @@ -843,9 +843,6 @@ void mdb_cursor_close(MDB_cursor *cursor); * case of the #MDB_SET option, in which the \b key object is unchanged), and * the address and length of the data are returned in the object to which \b data * refers. - * @bug Cursors are not coordinated with write operations. If a cursor in a - * write transaction is performing a sequential scan while records are being - * inserted or deleted in the same transaction, the cursor will be corrupted. * @param[in] cursor A cursor handle returned by #mdb_cursor_open() * @param[in,out] key The key for a retrieved item * @param[in,out] data The data of a retrieved item