From 095cd25e2337d00f866d95b81dfe6fc29bc99f59 Mon Sep 17 00:00:00 2001
From: Leo Yuriev <leo@yuriev.ru>
Date: Wed, 5 Apr 2017 18:33:19 +0300
Subject: [PATCH] mdbx: check sys-pagesize for power-of-2.

---
 src/bits.h | 7 +++++++
 src/mdbx.c | 9 ++-------
 2 files changed, 9 insertions(+), 7 deletions(-)

diff --git a/src/bits.h b/src/bits.h
index 45c0d69c..57551a48 100644
--- a/src/bits.h
+++ b/src/bits.h
@@ -780,3 +780,10 @@ void mdbx_rthc_unlock(void);
 int mdbx_rthc_alloc(mdbx_thread_key_t *key, MDB_reader *begin, MDB_reader *end);
 void mdbx_rthc_remove(mdbx_thread_key_t key);
 void mdbx_rthc_cleanup(void);
+
+static __inline bool is_power2(size_t x) { return (x & (x - 1)) == 0; }
+
+static __inline size_t roundup2(size_t value, size_t granularity) {
+  assert(is_power2(granularity));
+  return (value + granularity - 1) & ~(granularity - 1);
+}
diff --git a/src/mdbx.c b/src/mdbx.c
index af89676a..1af8aec8 100644
--- a/src/mdbx.c
+++ b/src/mdbx.c
@@ -3631,6 +3631,8 @@ int __cold mdbx_env_create(MDB_env **env) {
   e->me_lfd = INVALID_HANDLE_VALUE;
   e->me_pid = mdbx_getpid();
   mdbx_env_setup_limits(e, e->me_os_psize = mdbx_syspagesize());
+  if (!is_power2(e->me_os_psize))
+    return MDB_INCOMPATIBLE;
   VALGRIND_CREATE_MEMPOOL(e, 0, 0);
   e->me_signature = MDBX_ME_SIGNATURE;
   *env = e;
@@ -3848,13 +3850,6 @@ static int __cold mdbx_env_open2(MDB_env *env, MDB_meta *meta) {
 
 /****************************************************************************/
 
-static __inline bool is_powerof2(size_t x) { return (x & (x - 1)) == 0; }
-
-static __inline size_t roundup2(size_t value, size_t granularity) {
-  assert(is_powerof2(granularity));
-  return (value + granularity - 1) & ~(granularity - 1);
-}
-
 /* Open and/or initialize the lock region for the environment. */
 static int __cold mdbx_env_setup_locks(MDB_env *env, char *lpath, int mode,
                                        int *excl) {