From 0b0ef908f8821d8e4f8d2f51ba407e480ef59b14 Mon Sep 17 00:00:00 2001
From: Howard Chu <hyc@symas.com>
Date: Wed, 9 Nov 2011 00:36:50 -0800
Subject: [PATCH] More pgno alignment tweaks
---
libraries/libmdb/mdb.c | 52 ++++++++++++++++++++++--------------------
1 file changed, 27 insertions(+), 25 deletions(-)
diff --git a/libraries/libmdb/mdb.c b/libraries/libmdb/mdb.c
index 154dbe2d61..15d323f4f9 100644
--- a/libraries/libmdb/mdb.c
+++ b/libraries/libmdb/mdb.c
@@ -669,6 +669,30 @@ typedef struct MDB_node {
/** The size of a key in a node */
#define NODEKSZ(node) ((node)->mn_ksize)
+ /** Copy a page number from src to dst */
+#ifdef MISALIGNED_OK
+#define COPY_PGNO(dst,src) dst = src
+#else
+#if SIZE_MAX > 4294967295UL
+#define COPY_PGNO(dst,src) do { \
+ unsigned short *s, *d; \
+ s = (unsigned short *)&(src); \
+ d = (unsigned short *)&(dst); \
+ *d++ = *s++; \
+ *d++ = *s++; \
+ *d++ = *s++; \
+ *d = *s; \
+} while (0)
+#else
+#define COPY_PGNO(dst,src) do { \
+ unsigned short *s, *d; \
+ s = (unsigned short *)&(src); \
+ d = (unsigned short *)&(dst); \
+ *d++ = *s++; \
+ *d = *s; \
+} while (0)
+#endif
+#endif
/** The address of a key in a LEAF2 page.
* LEAF2 pages are used for #MDB_DUPFIXED sorted-duplicate sub-DBs.
* There are no node headers, keys are stored contiguously.
@@ -4015,18 +4039,7 @@ more:
fp = NODEDATA(leaf);
if (flags == MDB_CURRENT) {
fp->mp_flags |= P_DIRTY;
-#ifdef MISALIGNED_OK
- fp->mp_pgno = mc->mc_pg[mc->mc_top]->mp_pgno;
-#else
- {
- unsigned short *src, *dst;
- int i;
- dst = (unsigned short *)&fp->mp_pgno;
- src = (unsigned short *)&mc->mc_pg[mc->mc_top]->mp_pgno;
- for (i=0; i<sizeof(fp->mp_pgno)/sizeof(unsigned short); i++)
- *dst++ = *src++;
- }
-#endif
+ COPY_PGNO(fp->mp_pgno, mc->mc_pg[mc->mc_top]->mp_pgno);
mc->mc_xcursor->mx_cursor.mc_pg[0] = fp;
flags |= F_DUPDATA;
goto put_sub;
@@ -4566,7 +4579,7 @@ mdb_node_shrink(MDB_page *mp, indx_t indx)
xp->mp_lower = sp->mp_lower;
xp->mp_flags = sp->mp_flags;
xp->mp_pad = sp->mp_pad;
- xp->mp_pgno = mp->mp_pgno;
+ COPY_PGNO(xp->mp_pgno, mp->mp_pgno);
/* shift lower nodes upward */
ptr = mp->mp_ptrs[indx];
@@ -4633,18 +4646,7 @@ mdb_xcursor_init1(MDB_cursor *mc, MDB_node *node)
mx->mx_db.md_leaf_pages = 1;
mx->mx_db.md_overflow_pages = 0;
mx->mx_db.md_entries = NUMKEYS(fp);
-#ifdef MISALIGNED_OK
- mx->mx_db.md_root = fp->mp_pgno;
-#else
- {
- unsigned short *src, *dst;
- int i;
- dst = (unsigned short *)&mx->mx_db.md_root;
- src = (unsigned short *)&fp->mp_pgno;
- for (i=0; i<sizeof(fp->mp_pgno)/sizeof(unsigned short); i++)
- *dst++ = *src++;
- }
-#endif
+ COPY_PGNO(mx->mx_db.md_root, fp->mp_pgno);
mx->mx_cursor.mc_snum = 1;
mx->mx_cursor.mc_flags = C_INITIALIZED|C_SUB;
mx->mx_cursor.mc_top = 0;
--
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