From 5e1721efdd26936c0b9c37aa7a4b5edfd41e77db Mon Sep 17 00:00:00 2001
From: Leo Yuriev <leo@yuriev.ru>
Date: Thu, 26 Oct 2017 21:22:25 +0300
Subject: [PATCH] mdbx: fix mdbx_robust_trylock().

---
 src/lck-posix.c | 10 ++++------
 1 file changed, 4 insertions(+), 6 deletions(-)

diff --git a/src/lck-posix.c b/src/lck-posix.c
index 0c8cb41b..2aeed6f4 100644
--- a/src/lck-posix.c
+++ b/src/lck-posix.c
@@ -1,4 +1,4 @@
-/*
+/*
  * Copyright 2015-2017 Leonid Yuriev <leo@yuriev.ru>
  * and other libmdbx authors: please see AUTHORS file.
  * All rights reserved.
@@ -186,9 +186,9 @@ static int mdbx_robust_lock(MDBX_env *env, pthread_mutex_t *mutex) {
 
 static int mdbx_robust_trylock(MDBX_env *env, pthread_mutex_t *mutex) {
   int rc = pthread_mutex_trylock(mutex);
-  if (unlikely(rc != 0))
+  if (unlikely(rc != 0 && rc != EBUSY))
     rc = mdbx_mutex_failed(env, mutex, rc);
-  return rc;
+  return (rc != EBUSY) ? rc : MDBX_BUSY;
 }
 
 static int mdbx_robust_unlock(MDBX_env *env, pthread_mutex_t *mutex) {
@@ -327,9 +327,7 @@ static int __cold mdbx_mutex_failed(MDBX_env *env, pthread_mutex_t *mutex,
 #endif /* MDBX_USE_ROBUST */
 
   mdbx_error("mutex (un)lock failed, %s", mdbx_strerror(rc));
-  if (rc == EBUSY) {
-    rc = MDBX_BUSY;
-  } else if (rc != EDEADLK && rc != EBUSY) {
+  if (rc != EDEADLK) {
     env->me_flags |= MDBX_FATAL_ERROR;
     rc = MDBX_PANIC;
   }