From b4ecbd78d9d153f653eb338ce34d553c4c96fb65 Mon Sep 17 00:00:00 2001
From: Howard Chu <hyc@symas.com>
Date: Wed, 18 Jun 2014 12:29:13 -0700
Subject: [PATCH] Fix some overwrite quirks

Was skipping the overwrite in some cases, if the cmp function
said the new and old already matched. We should always perform
the overwrite anyway, since the cmp function may only be doing
a prefix compare and the data may actually be different.
---
 libraries/liblmdb/mdb.c | 20 ++++++++++----------
 1 file changed, 10 insertions(+), 10 deletions(-)

diff --git a/libraries/liblmdb/mdb.c b/libraries/liblmdb/mdb.c
index 734b63a..8445f07 100644
--- a/libraries/liblmdb/mdb.c
+++ b/libraries/liblmdb/mdb.c
@@ -5457,8 +5457,10 @@ set1:
 	mc->mc_flags &= ~C_EOF;
 
 	if (IS_LEAF2(mp)) {
-		key->mv_size = mc->mc_db->md_pad;
-		key->mv_data = LEAF2KEY(mp, mc->mc_ki[mc->mc_top], key->mv_size);
+		if (op == MDB_SET_RANGE || op == MDB_SET_KEY) {
+			key->mv_size = mc->mc_db->md_pad;
+			key->mv_data = LEAF2KEY(mp, mc->mc_ki[mc->mc_top], key->mv_size);
+		}
 		return MDB_SUCCESS;
 	}
 
@@ -5942,13 +5944,12 @@ mdb_cursor_put(MDB_cursor *mc, MDB_val *key, MDB_val *data,
 	} else {
 		/* there's only a key anyway, so this is a no-op */
 		if (IS_LEAF2(mc->mc_pg[mc->mc_top])) {
+			char *ptr;
 			unsigned int ksize = mc->mc_db->md_pad;
 			if (key->mv_size != ksize)
 				return MDB_BAD_VALSIZE;
-			if (flags == MDB_CURRENT) {
-				char *ptr = LEAF2KEY(mc->mc_pg[mc->mc_top], mc->mc_ki[mc->mc_top], ksize);
-				memcpy(ptr, key->mv_data, ksize);
-			}
+			ptr = LEAF2KEY(mc->mc_pg[mc->mc_top], mc->mc_ki[mc->mc_top], ksize);
+			memcpy(ptr, key->mv_data, ksize);
 			return MDB_SUCCESS;
 		}
 
@@ -5978,12 +5979,12 @@ more:
 				if (mc->mc_dbx->md_dcmp == mdb_cmp_int && olddata.mv_size == sizeof(size_t))
 					mc->mc_dbx->md_dcmp = mdb_cmp_clong;
 #endif
-				/* if data matches, skip it */
+				/* does data match? */
 				if (!mc->mc_dbx->md_dcmp(data, &olddata)) {
 					if (flags & MDB_NODUPDATA)
 						return MDB_KEYEXIST;
-					rc = MDB_SUCCESS;
-					goto next_sub;
+					/* overwrite it */
+					goto current;
 				}
 
 				/* Back up original data item */
@@ -6259,7 +6260,6 @@ put_sub:
 			 */
 			mc->mc_flags |= C_INITIALIZED;
 		}
-next_sub:
 		if (flags & MDB_MULTIPLE) {
 			if (!rc) {
 				mcount++;