Commit 6e05ca17 authored by Howard Chu's avatar Howard Chu
Browse files

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.)
parent fe114336
......@@ -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);
......
......@@ -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.
......
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