From: Howard Chu <hyc@openldap.org>
Date: Wed, 11 Nov 2015 00:02:06 +0000 (+0000)
Subject: Tweak robust mutex detection for glibc
X-Git-Tag: LMDB_0.9.17~43
X-Git-Url: https://git.sur5r.net/?p=openldap;a=commitdiff_plain;h=79b12bbd7bb806c7f70b305e976b8c3e63823f2a

Tweak robust mutex detection for glibc
---

diff --git a/libraries/liblmdb/mdb.c b/libraries/liblmdb/mdb.c
index 98c73830e0..9af3704f78 100644
--- a/libraries/liblmdb/mdb.c
+++ b/libraries/liblmdb/mdb.c
@@ -238,7 +238,9 @@ typedef SSIZE_T	ssize_t;
 #define MDB_OWNERDEAD	EOWNERDEAD	/**< #LOCK_MUTEX0() result if dead owner */
 #endif
 
-
+#ifdef __GLIBC__
+#define	GLIBC_VER	((__GLIBC__ << 16 )| __GLIBC_MINOR__)
+#endif
 /** Some platforms define the EOWNERDEAD error code
  * even though they don't support Robust Mutexes.
  * Compile with -DMDB_USE_ROBUST=0, or use some other
@@ -248,12 +250,19 @@ typedef SSIZE_T	ssize_t;
  * either.)
  */
 #ifndef MDB_USE_ROBUST
-/* Android currently lacks Robust Mutex support */
-#if defined(ANDROID) && defined(MDB_USE_POSIX_MUTEX) && !defined(MDB_USE_ROBUST)
-#define MDB_USE_ROBUST	0
-#else
-#define MDB_USE_ROBUST	1
-#endif
+/* Android currently lacks Robust Mutex support. So does glibc < 2.4. */
+# if defined(MDB_USE_POSIX_MUTEX) && (defined(ANDROID) || \
+	(defined(__GLIBC__) && GLIBC_VER < 0x020004))
+#  define MDB_USE_ROBUST	0
+# else
+#  define MDB_USE_ROBUST	1
+/* glibc < 2.10 only provided _np API */
+#  if defined(__GLIBC__) && GLIBC_VER < 0x02000a
+#   define PTHREAD_MUTEX_ROBUST	PTHREAD_MUTEX_ROBUST_NP
+#   define pthread_mutexattr_setrobust(attr, flag)	pthread_mutexattr_setrobust_np(attr, flag)
+#   define pthread_mutex_consistent(mutex)	pthread_mutex_consistent_np(mutex)
+#  endif
+# endif
 #endif /* MDB_USE_ROBUST */
 
 #if defined(MDB_OWNERDEAD) && MDB_USE_ROBUST