More pgno alignment tweaks

diff --git a/libraries/libmdb/mdb.c b/libraries/libmdb/mdb.c
index 154dbe2d610a348bf737d130475aee94b94e7660..15d323f4f98a0c88102d629724b6bfdf188b7dd2 100644 (file)
--- 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;