NULL dereference fixes in code base after running with 'clang'

* 212 logical (NULL deref/divide by zero) errors reduced to 28
  (27 of them in contrib/ and lex part of codebase, 1 is invalid)
* 11 API errors reduced to 0

Signed-off-by: Amar Tumballi <amar@gluster.com>
Signed-off-by: Anand V. Avati <avati@dev.gluster.com>

BUG: 966 (NULL check for avoiding NULL dereferencing of pointers..)
URL: http://bugs.gluster.com/cgi-bin/bugzilla3/show_bug.cgi?id=966

1 files changed, 9 insertions, 7 deletions

diff --git a/xlators/protocol/legacy/server/src/server-helpers.c b/xlators/protocol/legacy/server/src/server-helpers.c
index 7ab2ce88531..595916a3656 100644
--- a/xlators/protocol/legacy/server/src/server-helpers.c
+++ b/xlators/protocol/legacy/server/src/server-helpers.c
@@ -427,15 +427,17 @@ server_connection_destroy (xlator_t *this, server_connection_t *conn)
                 INIT_LIST_HEAD (&file_lockers);
                 INIT_LIST_HEAD (&dir_lockers);
 
-                LOCK (&ltable->lock);
-                {
-                        list_splice_init (&ltable->file_lockers,
-                                          &file_lockers);
+                if (ltable) {
+                        LOCK (&ltable->lock);
+                        {
+                                list_splice_init (&ltable->file_lockers,
+                                                  &file_lockers);
 
-                        list_splice_init (&ltable->dir_lockers, &dir_lockers);
+                                list_splice_init (&ltable->dir_lockers, &dir_lockers);
+                        }
+                        UNLOCK (&ltable->lock);
+                        GF_FREE (ltable);
                 }
-                UNLOCK (&ltable->lock);
-                GF_FREE (ltable);
 
                 flock.l_type  = F_UNLCK;
                 flock.l_start = 0;