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vl32b
Howard Chu 9 years ago
parent 6f8b48a168
commit f633e2530f
4 changed files with 160 additions and 44 deletions
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  1. 1
      libraries/liblmdb/lmdb.h
  2. 120
      libraries/liblmdb/mdb.c
  3. 68
      libraries/liblmdb/midl.c
  4. 15
      libraries/liblmdb/midl.h

1
libraries/liblmdb/lmdb.h
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@ -158,6 +158,7 @@
#define _LMDB_H_
#include <sys/types.h>
#include <inttypes.h>
#ifdef __cplusplus
extern "C" {

120
libraries/liblmdb/mdb.c
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@ -1201,7 +1201,7 @@ struct MDB_txn {
unsigned char *mt_dbflags;
#ifdef MDB_VL32
/** List of read-only pages */
MDB_ID2L mt_rpages;
MDB_ID3L mt_rpages;
#endif
/** Number of DB records in use, or 0 when the txn is finished.
* This number only ever increments until the txn finishes; we
@ -1897,6 +1897,33 @@ mdb_dlist_free(MDB_txn *txn)
dl[0].mid = 0;
}
#ifdef MDB_VL32
static void
mdb_page_unref(MDB_txn *txn, MDB_page *mp)
{
MDB_ID3L rl = txn->mt_rpages;
unsigned x = mdb_mid3l_search(rl, mp->mp_pgno);
if (x <= rl[0].mid && rl[x].mid == mp->mp_pgno) {
rl[x].mref--;
if (rl[x].mref)
return;
#ifdef _WIN32
UnmapViewOfFile(rl[x].mptr);
#else
munmap(mp, txn->mt_env->me_psize * rl[x].mcnt);
#endif
while (x < rl[0].mid) {
rl[x] = rl[x+1];
x++;
}
rl[0].mid--;
}
}
#define MDB_PAGE_UNREF(txn, mp) mdb_page_unref(txn, mp)
#else
#define MDB_PAGE_UNREF(txn, mp)
#endif /* MDB_VL32 */
/** Loosen or free a single page.
* Saves single pages to a list for future reuse
* in this same txn. It has been pulled from the freeDB
@ -2576,20 +2603,7 @@ done:
}
}
}
#ifdef MDB_VL32
{
MDB_ID2L rl = mc->mc_txn->mt_rpages;
unsigned x = mdb_mid2l_search(rl, mp->mp_pgno);
if (x <= rl[0].mid && rl[x].mid == mp->mp_pgno) {
munmap(mp, mc->mc_txn->mt_env->me_psize);
while (x < rl[0].mid) {
rl[x] = rl[x+1];
x++;
}
rl[0].mid--;
}
}
#endif
MDB_PAGE_UNREF(mc->mc_txn, mp);
return 0;
fail:
@ -2711,10 +2725,7 @@ mdb_cursors_close(MDB_txn *txn, unsigned merge)
#ifdef _WIN32
UnmapViewOfFile(txn->mt_rpages[i].mptr);
#else
MDB_page *mp = txn->mt_rpages[i].mptr;
int size = txn->mt_env->me_psize;
if (IS_OVERFLOW(mp)) size *= mp->mp_pages;
munmap(mp, size);
munmap(txn->mt_rpages[i].mptr, txn->mt_env->me_psize * txn->mt_rpages[i].mcnt);
#endif
}
}
@ -2967,7 +2978,7 @@ mdb_txn_begin(MDB_env *env, MDB_txn *parent, unsigned int flags, MDB_txn **ret)
}
#ifdef MDB_VL32
if (!parent) {
txn->mt_rpages = calloc(MDB_IDL_UM_SIZE, sizeof(MDB_ID2));
txn->mt_rpages = calloc(MDB_IDL_UM_SIZE, sizeof(MDB_ID3));
if (!txn->mt_rpages) {
free(txn);
return ENOMEM;
@ -5079,7 +5090,7 @@ mdb_env_open(MDB_env *env, const char *path, unsigned int flags, mdb_mode_t mode
txn->mt_dbflags = (unsigned char *)(txn->mt_dbiseqs + env->me_maxdbs);
txn->mt_env = env;
#ifdef MDB_VL32
txn->mt_rpages = calloc(MDB_IDL_UM_SIZE, sizeof(MDB_ID2));
txn->mt_rpages = calloc(MDB_IDL_UM_SIZE, sizeof(MDB_ID3));
if (!txn->mt_rpages) {
free(txn);
rc = ENOMEM;
@ -5523,9 +5534,10 @@ mdb_page_get(MDB_txn *txn, pgno_t pgno, MDB_page **ret, int *lvl)
level = 0;
#ifdef MDB_VL32
{
unsigned x = mdb_mid2l_search(txn->mt_rpages, pgno);
unsigned x = mdb_mid3l_search(txn->mt_rpages, pgno);
if (x <= txn->mt_rpages[0].mid && txn->mt_rpages[x].mid == pgno) {
p = txn->mt_rpages[x].mptr;
txn->mt_rpages[x].mref++;
goto done;
}
if (txn->mt_rpages[0].mid >= MDB_IDL_UM_MAX) {
@ -5533,9 +5545,9 @@ mdb_page_get(MDB_txn *txn, pgno_t pgno, MDB_page **ret, int *lvl)
mdb_tassert(txn, 0);
}
if (txn->mt_rpages[0].mid < MDB_IDL_UM_SIZE) {
MDB_ID2 id2;
MDB_ID3 id3;
size_t len = env->me_psize;
int np;
int np = 1;
#ifdef _WIN32
off_t off = pgno * env->me_psize;
DWORD lo, hi;
@ -5566,9 +5578,11 @@ mdb_page_get(MDB_txn *txn, pgno_t pgno, MDB_page **ret, int *lvl)
return errno;
}
#endif
id2.mid = pgno;
id2.mptr = p;
mdb_mid2l_insert(txn->mt_rpages, &id2);
id3.mid = pgno;
id3.mptr = p;
id3.mcnt = np;
id3.mref = 1;
mdb_mid3l_insert(txn->mt_rpages, &id3);
goto done;
}
}
@ -5745,10 +5759,22 @@ mdb_page_search(MDB_cursor *mc, MDB_val *key, int flags)
}
mdb_cassert(mc, root > 1);
if (!mc->mc_pg[0] || mc->mc_pg[0]->mp_pgno != root)
if (!mc->mc_pg[0] || mc->mc_pg[0]->mp_pgno != root) {
#ifdef MDB_VL32
if (mc->mc_pg[0])
MDB_PAGE_UNREF(mc->mc_txn, mc->mc_pg[0]);
#endif
if ((rc = mdb_page_get(mc->mc_txn, root, &mc->mc_pg[0], NULL)) != 0)
return rc;
}
#ifdef MDB_VL32
{
int i;
for (i=1; i<mc->mc_snum; i++)
MDB_PAGE_UNREF(mc->mc_txn, mc->mc_pg[i]);
}
#endif
mc->mc_snum = 1;
mc->mc_top = 0;
@ -5880,7 +5906,7 @@ mdb_get(MDB_txn *txn, MDB_dbi dbi,
{
MDB_cursor mc;
MDB_xcursor mx;
int exact = 0;
int exact = 0, rc;
DKBUF;
DPRINTF(("===> get db %u key [%s]", dbi, DKEY(key)));
@ -5892,7 +5918,16 @@ mdb_get(MDB_txn *txn, MDB_dbi dbi,
return MDB_BAD_TXN;
mdb_cursor_init(&mc, txn, dbi, &mx);
return mdb_cursor_set(&mc, key, data, MDB_SET, &exact);
rc = mdb_cursor_set(&mc, key, data, MDB_SET, &exact);
#ifdef MDB_VL32
{
int i;
/* leave the final page containing the data item, unref the rest */
for (i=0; i<mc.mc_top; i++)
MDB_PAGE_UNREF(txn, mc.mc_pg[i]);
}
#endif
return rc;
}
/** Find a sibling for a page.
@ -5944,20 +5979,7 @@ mdb_cursor_sibling(MDB_cursor *mc, int move_right)
}
mdb_cassert(mc, IS_BRANCH(mc->mc_pg[mc->mc_top]));
#ifdef MDB_VL32
{
MDB_ID2L rl = mc->mc_txn->mt_rpages;
unsigned x = mdb_mid2l_search(rl, op->mp_pgno);
if (x <= rl[0].mid && rl[x].mid == op->mp_pgno) {
munmap(op, mc->mc_txn->mt_env->me_psize);
while (x < rl[0].mid) {
rl[x] = rl[x+1];
x++;
}
rl[0].mid--;
}
}
#endif
MDB_PAGE_UNREF(mc->mc_txn, op);
indx = NODEPTR(mc->mc_pg[mc->mc_top], mc->mc_ki[mc->mc_top]);
if ((rc = mdb_page_get(mc->mc_txn, NODEPGNO(indx), &mp, NULL)) != 0) {
@ -9990,6 +10012,11 @@ mdb_drop0(MDB_cursor *mc, int subs)
mdb_cursor_pop(mc);
mdb_cursor_copy(mc, &mx);
#ifdef MDB_VL32
/* bump refcount for mx's pages */
for (i=0; i<mc->mc_snum; i++)
mdb_page_get(txn, mc->mc_pg[i]->mp_pgno, &mx.mc_pg[i], NULL);
#endif
while (mc->mc_snum > 0) {
MDB_page *mp = mc->mc_pg[mc->mc_top];
unsigned n = NUMKEYS(mp);
@ -10049,6 +10076,11 @@ mdb_drop0(MDB_cursor *mc, int subs)
done:
if (rc)
txn->mt_flags |= MDB_TXN_ERROR;
#ifdef MDB_VL32
/* drop refcount for mx's pages */
for (i=0; i<mc->mc_snum; i++)
MDB_PAGE_UNREF(txn, mx.mc_pg[i]);
#endif
} else if (rc == MDB_NOTFOUND) {
rc = MDB_SUCCESS;
}

68
libraries/liblmdb/midl.c
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@ -354,5 +354,73 @@ int mdb_mid2l_append( MDB_ID2L ids, MDB_ID2 *id )
return 0;
}
#ifdef MDB_VL32
unsigned mdb_mid3l_search( MDB_ID3L ids, MDB_ID id )
{
/*
* binary search of id in ids
* if found, returns position of id
* if not found, returns first position greater than id
*/
unsigned base = 0;
unsigned cursor = 1;
int val = 0;
unsigned n = (unsigned)ids[0].mid;
while( 0 < n ) {
unsigned pivot = n >> 1;
cursor = base + pivot + 1;
val = CMP( id, ids[cursor].mid );
if( val < 0 ) {
n = pivot;
} else if ( val > 0 ) {
base = cursor;
n -= pivot + 1;
} else {
return cursor;
}
}
if( val > 0 ) {
++cursor;
}
return cursor;
}
int mdb_mid3l_insert( MDB_ID3L ids, MDB_ID3 *id )
{
unsigned x, i;
x = mdb_mid3l_search( ids, id->mid );
if( x < 1 ) {
/* internal error */
return -2;
}
if ( x <= ids[0].mid && ids[x].mid == id->mid ) {
/* duplicate */
return -1;
}
if ( ids[0].mid >= MDB_IDL_UM_MAX ) {
/* too big */
return -2;
} else {
/* insert id */
ids[0].mid++;
for (i=(unsigned)ids[0].mid; i>x; i--)
ids[i] = ids[i-1];
ids[x] = *id;
}
return 0;
}
#endif /* MDB_VL32 */
/** @} */
/** @} */

15
libraries/liblmdb/midl.h
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@ -27,6 +27,7 @@
#define _MDB_MIDL_H_
#include <stddef.h>
#include <inttypes.h>
#ifdef __cplusplus
extern "C" {
@ -185,6 +186,20 @@ int mdb_mid2l_insert( MDB_ID2L ids, MDB_ID2 *id );
*/
int mdb_mid2l_append( MDB_ID2L ids, MDB_ID2 *id );
#ifdef MDB_VL32
typedef struct MDB_ID3 {
MDB_ID mid; /**< The ID */
void *mptr; /**< The pointer */
int mcnt; /**< Number of pages */
int mref; /**< Refcounter */
} MDB_ID3;
typedef MDB_ID3 *MDB_ID3L;
unsigned mdb_mid3l_search( MDB_ID3L ids, MDB_ID id );
int mdb_mid3l_insert( MDB_ID3L ids, MDB_ID3 *id );
#endif /* MDB_VL32 */
/** @} */
/** @} */
#ifdef __cplusplus

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