ITS#7713 handle 65536 byte page size

Fix mp_lower/mp_upper to exclude PAGEHDRSZ, which means our
max mp_upper is now pagesize - PAGEHDRSZ and won't overflow.
Currently must define MDB_DEVEL to use. Will be default for
LMDB 1.0/OpenLDAP 2.5

diff --git a/libraries/liblmdb/mdb.c b/libraries/liblmdb/mdb.c
index 6d02f8e5d1d16bc9b9e8fb0278e986599898891c..d31cdb2c42ef5d0f5e7ad10af80b5464854f37dc 100644 (file)
--- a/libraries/liblmdb/mdb.c
+++ b/libraries/liblmdb/mdb.c
@@ -693,8 +693,17 @@ typedef struct MDB_page {
        /** Address of first usable data byte in a page, after the header */
 #define METADATA(p)     ((void *)((char *)(p) + PAGEHDRSZ))
 
+       /** ITS#7713, change PAGEBASE to handle 65536 byte pages */
+#ifdef MDB_DEVEL
+#define        MP_LOBASE       0
+#define        MP_HIBASE       PAGEHDRSZ
+#else
+#define        MP_LOBASE       PAGEHDRSZ
+#define        MP_HIBASE       0
+#endif
+
        /** Number of nodes on a page */
-#define NUMKEYS(p)      (((p)->mp_lower - PAGEHDRSZ) >> 1)
+#define NUMKEYS(p)      (((p)->mp_lower - MP_LOBASE) >> 1)
 
        /** The amount of space remaining in the page */
 #define SIZELEFT(p)     (indx_t)((p)->mp_upper - (p)->mp_lower)
@@ -775,7 +784,7 @@ typedef struct MDB_node {
 #define LEAFSIZE(k, d)  (NODESIZE + (k)->mv_size + (d)->mv_size)
 
        /** Address of node \b i in page \b p */
-#define NODEPTR(p, i)   ((MDB_node *)((char *)(p) + (p)->mp_ptrs[i]))
+#define NODEPTR(p, i)   ((MDB_node *)((char *)(p) + (p)->mp_ptrs[i] + MP_HIBASE))
 
        /** Address of the key for the node */
 #define NODEKEY(node)   (void *)((node)->mn_data)
@@ -1385,7 +1394,7 @@ mdb_page_list(MDB_page *mp)
                total = EVEN(total);
        }
        fprintf(stderr, "Total: header %d + contents %d + unused %d\n",
-               IS_LEAF2(mp) ? PAGEHDRSZ : mp->mp_lower, total, SIZELEFT(mp));
+               IS_LEAF2(mp) ? PAGEHDRSZ : MP_HIBASE + mp->mp_lower, total, SIZELEFT(mp));
 }
 
 void
@@ -2040,9 +2049,9 @@ mdb_page_copy(MDB_page *dst, MDB_page *src, unsigned int psize)
         */
        if ((unused &= -Align) && !IS_LEAF2(src)) {
                upper &= -Align;
-               memcpy(dst, src, (lower + (Align-1)) & -Align);
-               memcpy((pgno_t *)((char *)dst+upper), (pgno_t *)((char *)src+upper),
-                       psize - upper);
+               memcpy(dst, src, (lower + MP_HIBASE + (Align-1)) & -Align);
+               memcpy((pgno_t *)((char *)dst+upper+MP_HIBASE), (pgno_t *)((char *)src+upper+MP_HIBASE),
+                       psize - upper - MP_HIBASE);
        } else {
                memcpy(dst, src, psize - unused);
        }
@@ -5936,7 +5945,7 @@ mdb_cursor_put(MDB_cursor *mc, MDB_val *key, MDB_val *data,
                        fp_flags = P_LEAF|P_DIRTY;
                        fp = env->me_pbuf;
                        fp->mp_pad = data->mv_size; /* used if MDB_DUPFIXED */
-                       fp->mp_lower = fp->mp_upper = olddata.mv_size = PAGEHDRSZ;
+                       fp->mp_lower = fp->mp_upper = olddata.mv_size = MP_LOBASE;
                        goto prep_subDB;
                }
        } else {
@@ -5991,7 +6000,7 @@ more:
 
                                /* Make sub-page header for the dup items, with dummy body */
                                fp->mp_flags = P_LEAF|P_DIRTY|P_SUBP;
-                               fp->mp_lower = PAGEHDRSZ;
+                               fp->mp_lower = MP_LOBASE;
                                xdata.mv_size = PAGEHDRSZ + dkey.mv_size + data->mv_size;
                                if (mc->mc_db->md_flags & MDB_DUPFIXED) {
                                        fp->mp_flags |= P_LEAF2;
@@ -6001,8 +6010,8 @@ more:
                                        xdata.mv_size += 2 * (sizeof(indx_t) + NODESIZE) +
                                                (dkey.mv_size & 1) + (data->mv_size & 1);
                                }
-                               fp->mp_upper = xdata.mv_size;
-                               olddata.mv_size = fp->mp_upper; /* pretend olddata is fp */
+                               fp->mp_upper = xdata.mv_size - MP_HIBASE;
+                               olddata.mv_size = xdata.mv_size; /* pretend olddata is fp */
                        } else if (leaf->mn_flags & F_SUBDATA) {
                                /* Data is on sub-DB, just store it */
                                flags |= F_DUPDATA|F_SUBDATA;
@@ -6069,7 +6078,7 @@ prep_subDB:
                                if (fp_flags & P_LEAF2) {
                                        memcpy(METADATA(mp), METADATA(fp), NUMKEYS(fp) * fp->mp_pad);
                                } else {
-                                       memcpy((char *)mp + mp->mp_upper, (char *)fp + fp->mp_upper,
+                                       memcpy((char *)mp + mp->mp_upper + MP_HIBASE, (char *)fp + fp->mp_upper + MP_HIBASE,
                                                olddata.mv_size - fp->mp_upper);
                                        for (i=0; i<NUMKEYS(fp); i++)
                                                mp->mp_ptrs[i] = fp->mp_ptrs[i] + offset;
@@ -6392,8 +6401,8 @@ mdb_page_new(MDB_cursor *mc, uint32_t flags, int num, MDB_page **mp)
        DPRINTF(("allocated new mpage %"Z"u, page size %u",
            np->mp_pgno, mc->mc_txn->mt_env->me_psize));
        np->mp_flags = flags | P_DIRTY;
-       np->mp_lower = PAGEHDRSZ;
-       np->mp_upper = mc->mc_txn->mt_env->me_psize;
+       np->mp_lower = MP_LOBASE;
+       np->mp_upper = mc->mc_txn->mt_env->me_psize - MP_HIBASE;
 
        if (IS_BRANCH(np))
                mc->mc_db->md_branch_pages++;
@@ -6646,7 +6655,7 @@ mdb_node_del(MDB_cursor *mc, int ksize)
                }
        }
 
-       base = (char *)mp + mp->mp_upper;
+       base = (char *)mp + mp->mp_upper + MP_HIBASE;
        memmove(base + sz, base, ptr - mp->mp_upper);
 
        mp->mp_lower -= sizeof(indx_t);
@@ -6700,7 +6709,7 @@ mdb_node_shrink(MDB_page *mp, indx_t indx)
                        mp->mp_ptrs[i] += delta;
        }
 
-       base = (char *)mp + mp->mp_upper;
+       base = (char *)mp + mp->mp_upper + MP_HIBASE;
        memmove(base + delta, base, ptr - mp->mp_upper + NODESIZE + NODEKSZ(node));
        mp->mp_upper += delta;
 }
@@ -6972,7 +6981,7 @@ mdb_update_key(MDB_cursor *mc, MDB_val *key)
                                mp->mp_ptrs[i] -= delta;
                }
 
-               base = (char *)mp + mp->mp_upper;
+               base = (char *)mp + mp->mp_upper + MP_HIBASE;
                len = ptr - mp->mp_upper + NODESIZE;
                memmove(base - delta, base, len);
                mp->mp_upper -= delta;
@@ -7763,8 +7772,8 @@ mdb_page_split(MDB_cursor *mc, MDB_val *newkey, MDB_val *newdata, pgno_t newpgno
                        }
                        copy->mp_pgno  = mp->mp_pgno;
                        copy->mp_flags = mp->mp_flags;
-                       copy->mp_lower = PAGEHDRSZ;
-                       copy->mp_upper = env->me_psize;
+                       copy->mp_lower = MP_LOBASE;
+                       copy->mp_upper = env->me_psize - MP_HIBASE;
 
                        /* prepare to insert */
                        for (i=0, j=0; i<nkeys; i++) {
@@ -7804,7 +7813,7 @@ mdb_page_split(MDB_cursor *mc, MDB_val *newkey, MDB_val *newdata, pgno_t newpgno
                                                psize += nsize;
                                                node = NULL;
                                        } else {
-                                               node = (MDB_node *)((char *)mp + copy->mp_ptrs[i]);
+                                               node = (MDB_node *)((char *)mp + copy->mp_ptrs[i] + MP_HIBASE);
                                                psize += NODESIZE + NODEKSZ(node) + sizeof(indx_t);
                                                if (IS_LEAF(mp)) {
                                                        if (F_ISSET(node->mn_flags, F_BIGDATA))
@@ -7824,7 +7833,7 @@ mdb_page_split(MDB_cursor *mc, MDB_val *newkey, MDB_val *newdata, pgno_t newpgno
                                sepkey.mv_size = newkey->mv_size;
                                sepkey.mv_data = newkey->mv_data;
                        } else {
-                               node = (MDB_node *)((char *)mp + copy->mp_ptrs[split_indx]);
+                               node = (MDB_node *)((char *)mp + copy->mp_ptrs[split_indx] + MP_HIBASE);
                                sepkey.mv_size = node->mn_ksize;
                                sepkey.mv_data = NODEKEY(node);
                        }
@@ -7905,7 +7914,7 @@ mdb_page_split(MDB_cursor *mc, MDB_val *newkey, MDB_val *newdata, pgno_t newpgno
                                /* Update index for the new key. */
                                mc->mc_ki[mc->mc_top] = j;
                        } else {
-                               node = (MDB_node *)((char *)mp + copy->mp_ptrs[i]);
+                               node = (MDB_node *)((char *)mp + copy->mp_ptrs[i] + MP_HIBASE);
                                rkey.mv_data = NODEKEY(node);
                                rkey.mv_size = node->mn_ksize;
                                if (IS_LEAF(mp)) {
@@ -7941,7 +7950,7 @@ mdb_page_split(MDB_cursor *mc, MDB_val *newkey, MDB_val *newdata, pgno_t newpgno
                mp->mp_lower = copy->mp_lower;
                mp->mp_upper = copy->mp_upper;
                memcpy(NODEPTR(mp, nkeys-1), NODEPTR(copy, nkeys-1),
-                       env->me_psize - copy->mp_upper);
+                       env->me_psize - copy->mp_upper - MP_HIBASE);
 
                /* reset back to original page */
                if (newindx < split_indx) {