Tweak conditionals for fdatasync hack

diff --git a/libraries/liblmdb/Makefile b/libraries/liblmdb/Makefile
index bca5cd3819c2f7d60426fa6f8eb48dab2dcbd740..2d0983eff04457c8f0e8d2cf785f23de46ca6606 100644 (file)
--- a/libraries/liblmdb/Makefile
+++ b/libraries/liblmdb/Makefile
@@ -11,6 +11,7 @@
 # - MDB_USE_POSIX_SEM
 # - MDB_DSYNC
 # - MDB_FDATASYNC
+# - MDB_FDATASYNC_WORKS
 # - MDB_USE_PWRITEV
 #
 # There may be other macros in mdb.c of interest. You should

diff --git a/libraries/liblmdb/mdb.c b/libraries/liblmdb/mdb.c
index a57576850873bbef2589870df115deee06a32f85..d93afdc45012bc7a1b9cfcff15d442046a8812e0 100644 (file)
--- a/libraries/liblmdb/mdb.c
+++ b/libraries/liblmdb/mdb.c
@@ -79,6 +79,12 @@ extern int cacheflush(char *addr, int nbytes, int cache);
 #define CACHEFLUSH(addr, bytes, cache)
 #endif
 
+#if defined(__linux) && !defined(MDB_FDATASYNC_WORKS)
+/** fdatasync is broken on ext3/ext4fs on older kernels, see
+ *     description in #mdb_env_open2 comments
+ */
+#define        BROKEN_FDATASYNC
+#endif
 
 #include <errno.h>
 #include <limits.h>
@@ -1143,7 +1149,7 @@ struct MDB_env {
        sem_t           *me_rmutex;             /* Shared mutexes are not supported */
        sem_t           *me_wmutex;
 #endif
-#ifdef __linux
+#ifdef BROKEN_FDATASYMC
        int             me_fsynconly;           /**< fdatasync is unreliable */
 #endif
        void            *me_userctx;     /**< User-settable context */
@@ -2318,7 +2324,7 @@ mdb_env_sync(MDB_env *env, int force)
                                rc = ErrCode();
 #endif
                } else {
-#ifdef __linux
+#ifdef BROKEN_FDATASYNC
                        if (env->me_fsynconly) {
                                if (fsync(env->me_fd))
                                        rc = ErrCode();
@@ -3861,7 +3867,7 @@ mdb_fsize(HANDLE fd, size_t *size)
        return MDB_SUCCESS;
 }
 
-#ifdef __linux
+#ifdef BROKEN_FDATASYNC
 #include <sys/utsname.h>
 #include <sys/vfs.h>
 #endif
@@ -3883,7 +3889,7 @@ mdb_env_open2(MDB_env *env)
        else
                env->me_pidquery = PROCESS_QUERY_INFORMATION;
 #endif /* _WIN32 */
-#ifdef __linux
+#ifdef BROKEN_FDATASYNC
        /* ext3/ext4 fdatasync is broken on some older Linux kernels.
         * https://lkml.org/lkml/2012/9/3/83
         * Kernels after 3.6-rc6 are known good.