From 6e05ca17e988754ae90fde1921765ba130bb90b2 Mon Sep 17 00:00:00 2001 From: Howard Chu Date: Sun, 2 Oct 2011 10:02:30 -0700 Subject: [PATCH] Add MDB_RESERVE mode When putting a record, just make space for the data, don't copy it. (Not compatible with MDB_DUPSORT, since the actual data is needed to determine the insert location.) --- libraries/libmdb/mdb.c | 53 ++++++++++++++++++++++++++++---------------------- libraries/libmdb/mdb.h | 4 ++++ 2 files changed, 34 insertions(+), 23 deletions(-) diff --git a/libraries/libmdb/mdb.c b/libraries/libmdb/mdb.c index 7b290ca..c6bc4f9 100644 --- a/libraries/libmdb/mdb.c +++ b/libraries/libmdb/mdb.c @@ -598,6 +598,10 @@ typedef struct MDB_node { #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 */ + +/** valid flags for #mdb_node_add() */ +#define NODE_ADD_FLAGS (F_DUPDATA|F_SUBDATA|MDB_RESERVE) + /** @} */ unsigned short mn_flags; /**< @ref mdb_node */ unsigned short mn_ksize; /**< key size */ @@ -886,7 +890,7 @@ static int mdb_page_search(MDB_cursor *mc, MDB_val *key, int modify); static int mdb_page_merge(MDB_cursor *csrc, MDB_cursor *cdst); static int mdb_page_split(MDB_cursor *mc, MDB_val *newkey, MDB_val *newdata, - pgno_t newpgno); + pgno_t newpgno, unsigned int nflags); static int mdb_env_read_header(MDB_env *env, MDB_meta *meta); static int mdb_env_read_meta(MDB_env *env, int *which); @@ -894,7 +898,7 @@ static int mdb_env_write_meta(MDB_txn *txn); static MDB_node *mdb_node_search(MDB_cursor *mc, MDB_val *key, int *exactp); static int mdb_node_add(MDB_cursor *mc, indx_t indx, - MDB_val *key, MDB_val *data, pgno_t pgno, uint8_t flags); + MDB_val *key, MDB_val *data, pgno_t pgno, unsigned int flags); static void mdb_node_del(MDB_page *mp, indx_t indx, int ksize); static void mdb_node_shrink(MDB_page *mp, indx_t indx); static int mdb_node_move(MDB_cursor *csrc, MDB_cursor *cdst); @@ -3875,6 +3879,7 @@ mdb_cursor_put(MDB_cursor *mc, MDB_val *key, MDB_val *data, int rc, rc2; char pbuf[PAGESIZE]; char dbuf[MAXKEYSIZE+1]; + unsigned int nflags; DKBUF; if (F_ISSET(mc->mc_txn->mt_flags, MDB_TXN_RDONLY)) @@ -4068,12 +4073,13 @@ current: rdata = data; new_sub: + nflags = flags & NODE_ADD_FLAGS; nsize = IS_LEAF2(mc->mc_pg[mc->mc_top]) ? key->mv_size : mdb_leaf_size(mc->mc_txn->mt_env, key, rdata); if (SIZELEFT(mc->mc_pg[mc->mc_top]) < nsize) { - rc = mdb_page_split(mc, key, rdata, P_INVALID); + rc = mdb_page_split(mc, key, rdata, P_INVALID, nflags); } else { /* There is room already in this leaf page. */ - rc = mdb_node_add(mc, mc->mc_ki[mc->mc_top], key, rdata, 0, 0); + rc = mdb_node_add(mc, mc->mc_ki[mc->mc_top], key, rdata, 0, nflags); if (rc == 0 && !do_sub) { /* Adjust other cursors pointing to mp */ MDB_cursor *m2, *m3; @@ -4100,12 +4106,6 @@ new_sub: if (rc != MDB_SUCCESS) mc->mc_txn->mt_flags |= MDB_TXN_ERROR; else { - /* Remember if we just added a subdatabase */ - if (flags & (F_SUBDATA|F_DUPDATA)) { - leaf = NODEPTR(mc->mc_pg[mc->mc_top], mc->mc_ki[mc->mc_top]); - leaf->mn_flags |= (flags & (F_SUBDATA|F_DUPDATA)); - } - /* 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 @@ -4117,6 +4117,7 @@ new_sub: put_sub: xdata.mv_size = 0; xdata.mv_data = ""; + leaf = NODEPTR(mc->mc_pg[mc->mc_top], mc->mc_ki[mc->mc_top]); if (flags & MDB_CURRENT) { xflags = MDB_CURRENT; } else { @@ -4311,7 +4312,7 @@ mdb_branch_size(MDB_env *env, MDB_val *key) */ static int mdb_node_add(MDB_cursor *mc, indx_t indx, - MDB_val *key, MDB_val *data, pgno_t pgno, uint8_t flags) + MDB_val *key, MDB_val *data, pgno_t pgno, unsigned int flags) { unsigned int i; size_t node_size = NODESIZE; @@ -4407,13 +4408,18 @@ mdb_node_add(MDB_cursor *mc, indx_t indx, if (F_ISSET(flags, F_BIGDATA)) memcpy(node->mn_data + key->mv_size, data->mv_data, sizeof(pgno_t)); + else if (F_ISSET(flags, MDB_RESERVE)) + data->mv_data = node->mn_data + key->mv_size; else memcpy(node->mn_data + key->mv_size, data->mv_data, data->mv_size); } else { memcpy(node->mn_data + key->mv_size, &ofp->mp_pgno, sizeof(pgno_t)); - memcpy(METADATA(ofp), data->mv_data, data->mv_size); + if (F_ISSET(flags, MDB_RESERVE)) + data->mv_data = METADATA(ofp); + else + memcpy(METADATA(ofp), data->mv_data, data->mv_size); } } @@ -5219,15 +5225,16 @@ mdb_del(MDB_txn *txn, MDB_dbi dbi, * @return 0 on success, non-zero on failure. */ static int -mdb_page_split(MDB_cursor *mc, MDB_val *newkey, MDB_val *newdata, pgno_t newpgno) +mdb_page_split(MDB_cursor *mc, MDB_val *newkey, MDB_val *newdata, pgno_t newpgno, + unsigned int nflags) { - uint8_t flags; + unsigned int flags; 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; MDB_node *node; - MDB_val sepkey, rkey, rdata; + MDB_val sepkey, rkey, xdata, *rdata = &xdata; MDB_page *copy; MDB_page *mp, *rp, *pp; unsigned int ptop; @@ -5385,7 +5392,7 @@ newsep: if (SIZELEFT(mn.mc_pg[ptop]) < mdb_branch_size(mc->mc_txn->mt_env, &sepkey)) { mn.mc_snum--; mn.mc_top--; - rc = mdb_page_split(&mn, &sepkey, NULL, rp->mp_pgno); + rc = mdb_page_split(&mn, &sepkey, NULL, rp->mp_pgno, 0); /* Right page might now have changed parent. * Check if left page also changed parent. @@ -5432,11 +5439,10 @@ newsep: rkey.mv_data = newkey->mv_data; rkey.mv_size = newkey->mv_size; if (IS_LEAF(mp)) { - rdata.mv_data = newdata->mv_data; - rdata.mv_size = newdata->mv_size; + rdata = newdata; } else pgno = newpgno; - flags = 0; + flags = nflags; ins_new = 1; @@ -5449,8 +5455,9 @@ newsep: rkey.mv_data = NODEKEY(node); rkey.mv_size = node->mn_ksize; if (IS_LEAF(mp)) { - rdata.mv_data = NODEDATA(node); - rdata.mv_size = NODEDSZ(node); + xdata.mv_data = NODEDATA(node); + xdata.mv_size = NODEDSZ(node); + rdata = &xdata; } else pgno = NODEPGNO(node); flags = node->mn_flags; @@ -5463,7 +5470,7 @@ newsep: rkey.mv_size = 0; } - rc = mdb_node_add(mc, j, &rkey, &rdata, pgno, flags); + rc = mdb_node_add(mc, j, &rkey, rdata, pgno, flags); } /* reset back to original page */ @@ -5539,7 +5546,7 @@ mdb_put(MDB_txn *txn, MDB_dbi dbi, return EINVAL; } - if ((flags & (MDB_NOOVERWRITE|MDB_NODUPDATA)) != flags) + if ((flags & (MDB_NOOVERWRITE|MDB_NODUPDATA|MDB_RESERVE)) != flags) return EINVAL; mdb_cursor_init(&mc, txn, dbi, &mx); diff --git a/libraries/libmdb/mdb.h b/libraries/libmdb/mdb.h index af82e56..3bb7e4c 100644 --- a/libraries/libmdb/mdb.h +++ b/libraries/libmdb/mdb.h @@ -189,6 +189,10 @@ typedef void (MDB_rel_func)(MDB_val *item, void *oldptr, void *newptr, void *rel #define MDB_NODUPDATA 0x20 /** For mdb_cursor_put: overwrite the current key/data pair */ #define MDB_CURRENT 0x40 +/** For put: Just reserve space for data, don't copy it. Return a + * pointer to the reserved space. + */ +#define MDB_RESERVE 0x10000 /* @} */ /** @brief Cursor Get operations. -- 2.7.4