ISAR/libmdbx
3
0
Fork 0
mirror of https://github.com/isar/libmdbx.git synced 2025-01-06 17:34:14 +08:00
Code Issues Packages Projects Releases Wiki Activity

mdbx: clarify ov-pages copying in cursor_put().

Browse Source 
Change-Id: I48ae57579a7d68178ec1857785ffdd6f0c0f7e13
This commit is contained in:
Leo Yuriev 2016-05-10 13:21:38 +03:00
parent 1ef0106b51
commit 09d7904317
1 changed files with 9 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

13
mdb.c
View File

@ -6885,7 +6885,6 @@ current:
*/ */
if (unlikely(level > 1)) { if (unlikely(level > 1)) {
/* It is writable only in a parent txn */ /* It is writable only in a parent txn */
size_t sz = (size_t) env->me_psize * ovpages, off;
MDB_page *np = mdb_page_malloc(mc->mc_txn, ovpages); MDB_page *np = mdb_page_malloc(mc->mc_txn, ovpages);
MDB_ID2 id2; MDB_ID2 id2;
if (unlikely(!np)) if (unlikely(!np))
@ -6899,8 +6898,13 @@ current:
* parent txn, in case the user peeks at MDB_RESERVEd * parent txn, in case the user peeks at MDB_RESERVEd
* or unused parts. Some users treat ovpages specially. * or unused parts. Some users treat ovpages specially.
*/ */
if (1 || /* LY: Hm, why we should do this differently in dependence from MDB_RESERVE? */ #if MDBX_MODE_ENABLED
!(flags & MDB_RESERVE)) { /* LY: New page will contain only header from origin,
* but no any payload */
memcpy(np, omp, PAGEHDRSZ);
#else
size_t sz = (size_t) env->me_psize * ovpages, off;
if (!(flags & MDB_RESERVE)) {
/* Skip the part where LMDB will put *data. /* Skip the part where LMDB will put *data.
* Copy end of page, adjusting alignment so * Copy end of page, adjusting alignment so
* compiler may copy words instead of bytes. * compiler may copy words instead of bytes.
@ -6910,7 +6914,8 @@ current:
(size_t *)((char *)omp + off), sz - off); (size_t *)((char *)omp + off), sz - off);
sz = PAGEHDRSZ; sz = PAGEHDRSZ;
} }
memcpy(np, omp, sz); /* Copy whole or beginning of page */ memcpy(np, omp, sz); /* Copy whole or header of page */
#endif /* MDBX_MODE_ENABLED */
omp = np; omp = np;
} }
SETDSZ(leaf, data->mv_size); SETDSZ(leaf, data->mv_size);