put(MDB_MULTIPLE): Skip existing item cleanly.

Don't set dkey.mv_size if mdb won't clear it before next iteration.

diff --git a/libraries/liblmdb/mdb.c b/libraries/liblmdb/mdb.c
index a6da9a591a191799f75475e56d097bc89030003c..92db028513653850cf4838f139d92483e863e8ec 100644 (file)
--- a/libraries/liblmdb/mdb.c
+++ b/libraries/liblmdb/mdb.c
@@ -5824,9 +5824,8 @@ more:
                                if (flags == MDB_CURRENT)
                                        goto current;
 
-                               dkey = olddata;
 #if UINT_MAX < SIZE_MAX
-                               if (mc->mc_dbx->md_dcmp == mdb_cmp_int && dkey.mv_size == sizeof(size_t))
+                               if (mc->mc_dbx->md_dcmp == mdb_cmp_int && olddata.mv_size == sizeof(size_t))
 #ifdef MISALIGNED_OK
                                        mc->mc_dbx->md_dcmp = mdb_cmp_long;
 #else
@@ -5834,7 +5833,7 @@ more:
 #endif
 #endif
                                /* if data matches, skip it */
-                               if (!mc->mc_dbx->md_dcmp(data, &dkey)) {
+                               if (!mc->mc_dbx->md_dcmp(data, &olddata)) {
                                        if (flags & MDB_NODUPDATA)
                                                rc = MDB_KEYEXIST;
                                        else if (flags & MDB_MULTIPLE)
@@ -5844,9 +5843,11 @@ more:
                                        return rc;
                                }
 
+                               /* Back up original data item */
+                               dkey.mv_size = olddata.mv_size;
+                               dkey.mv_data = memcpy(dbuf, olddata.mv_data, olddata.mv_size);
+
                                /* create a fake page for the dup items */
-                               memcpy(dbuf, dkey.mv_data, dkey.mv_size);
-                               dkey.mv_data = dbuf;
                                fp->mp_flags = P_LEAF|P_DIRTY|P_SUBP;
                                fp->mp_lower = PAGEHDRSZ;
                                xdata.mv_size = PAGEHDRSZ + dkey.mv_size + data->mv_size;